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# Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants

Author Message
Manager
Joined: 03 Aug 2011
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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19 Dec 2012, 17:40
1
KUDOS
hey everyone, I had my interview yesterday. Overall, I'd say it was a good experience. I feel I could have answered some questions better, but I think the nerves got to me, at least for the first 10 minutes.

Here are the questions I was asked

- Point out the career progression (this was really a walk me through your resume, but with an emphasis on career transitions in my current position)
- Goals
- Why MBA? Was not asked exactly like that, asked more like well if your goal is XYZ why do you need an MBA?
- Why Haas?
- If you were CEO what would you do?
- how are you different than other engineers?
- Questions for me?

Now that I think about it, there were a whole lotta questions .. certainly more than I anticipated.

Engineers... stay non-technical

Best of luck to everyone.
Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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08 Jan 2013, 13:50
1
KUDOS
I finished my interview and here is a write-up of my experience which may help some of the other applicants:

I was there 30 min. before my scheduled time. I was asked to show identification and was checked-in. The interviewer was on-time and called out my name at the lobby. She was very friendly and we made some small talk on our way to the interview room. She was a member of the AdCom.

The questions were pretty straightforward as mentioned by previous interviewees:
1. Resume walk through.
2. Pointed at one of my experiences on my resume and asked a specific question related to it.
3. Short-term & Long-term goals
4. How would Haas help me in achieving them?
5. Strengths?
6. Weaknesses?
7. What would my colleagues say about me?
8. What can the class learn from me?
9. How am I different from other engineers who apply to Haas?
10. Pick one of Haas' principles and give an example.

I asked her a few questions about the program. All of this in about 30 min. They generally don't go over the time limit.

Good Luck, everyone!
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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16 Jan 2013, 10:41
1
KUDOS
A couple of weeks left for the outcome on R1 applications. I hope they continue to call applicants for interviews and not waitlist them without one.
Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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18 Jan 2013, 16:27
1
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emomento wrote:
I am from the bay area so i can pick a day. i think the visitation day is only for non-local folks.

Ahhh....I guess being invited is a good thing regardless of where you live.
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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19 Jan 2013, 15:25
1
KUDOS
GoToHaas2016 wrote:
suchivuk wrote:
A couple of weeks left for the outcome on R1 applications. I hope they continue to call applicants for interviews and not waitlist them without one.

I am also getting a little nervous as I did not receive an invitation for an interview yet

Hi Folks,

When did you get all application material in place? (reference, transcript, etc). I think they will start looking into your file only after they get everything. So stay tuned, no worries.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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24 Jan 2013, 08:45
1
KUDOS
For those that haven't had an interview yet, this was an email I saw on the full time thread. I would imagine the EWMBA program works much the same.

Stephanie Fujii
Full-time Berkeley MBA Program
wrote:
Dear *******,
Greetings once again from Berkeley! It has been several weeks since you submitted your Haas application and I am sure you’re wondering what’s going on behind the scenes. At this point, I wanted to shed some light on the application process and address a few of the common questions we’ve received:
• I have not yet received an invitation to interview. What does that mean? It means that we are still reviewing applications. The Admissions Committee values the effort you put into this process and every application is reviewed by at least two readers. We have already sent out a number of interview invitations, but we will continue to invite candidates to interview over the next month up to the notification deadline.
• What happens if I don’t get an invitation to interview? You should not be discouraged if you do not receive an interview invitation by the notification date; we typically invite around 25% of our candidates to interview. Some applicants will be offered a place on the waitlist without having been interviewed. These waitlisted candidates are welcome to schedule an interview after the notification date.
• I have an important application update I’d like to share, is that possible? Since we are already well into reviewing applications we cannot guarantee that your new information will be considered. However, you are welcome to submit it to mbaadm@haas.berkeley.edu. Someone on our team will follow-up if necessary.
• I already had my interview. What happens now? As hard as it is to do, you wait. Your interviewer will submit their evaluation and the Admissions Committee will consider it in addition to the rest of your application. All admissions decisions will be released on the notification date.
• Can I expedite a decision before the notification deadline? Unfortunately, we cannot expedite an admissions decision under any circumstances.
• If I am admitted, what happens next? First, you celebrate! As you know this is a very competitive process so you are among a select group. You should be on the lookout for follow-up emails from Admissions, Financial Aid and current students with important dates, events, and ways to continue to connect with our community.
I hope this information has been helpful. I know this can be a stressful time and we appreciate your patience while we continue to review applications.
Stephanie
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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24 Jan 2013, 18:53
1
KUDOS
calstevej wrote:
rajcooper wrote:
Yeah, but if you're shooting for the stars (stanford), shouldn't you have the confidence to at least cross the moon (Haas FT)? Just saying...although it doesn't really matter at this point.

I did't apply to Haas because it was easy to get into. Quite the opposite, actually.

If an applicant gets waitlisted, do they have to wait until the R3 decision deadline to know whether or not they will be admitted?

"Those round 1 applicants offered a place on our waitlist will not be notified of a change of their status until the completion of our next round of applications (for example after round 2 decisions are released on March 28) and that may include a continued spot on our waitlist into round 3"

HTH
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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30 Jan 2013, 07:08
1
KUDOS
riskall wrote:
Packet...great response on the the linked thread and I completely agree with you...
You said you are from Seattle...I imagine you work for a certain large conglomerate on the east side?

Nope. I work for a mid-sized consulting firm. I actually don't have any ties to the Seattle area, I just want to live here and work doesn't care as long as I'm near an airport. So, I moved here from the Bay Area 3 or 4 years ago.
Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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30 Jan 2013, 17:02
1
KUDOS
MBACLASS2013 wrote:
I have lost my sleep
Last year the phone calls came one day prior to the published decision date.
If that is the case, it should be tomorrow.

Some calls came in the day of, and some admitted students mistakenly weren't called. I received an email admittance around 11:00am the day of last year. Best of luck to all of you!
Intern
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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31 Jan 2013, 12:07
1
KUDOS
speedingdaemon wrote:
I had read somewhere on gmatclub that last year, approx 750 students had applied for the 250 seats.
That means a 3:1 ratio. Since we have 27 applicants this year for R1. We should see at least 9 admit calls this year too...

Two things:

1. Based on anecdotal data, we're more likely to see "above average" (as far as per round applicants) rate of wait listed folks in R1 as they identify candidates that are "pretty solid, but we want to have a better idea of our entire class makeup before we admit another engineer/bay area/consultant/whatever"

2. I would expect that folks that have A. applied in R1 and B. are active in this thread to be generally of a higher caliber than your average applicant.

All that said, smart money is on us all getting in and the call delay being a big prank.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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31 Jan 2013, 17:19
1
KUDOS
speedingdaemon wrote:
well... its over for today...
its going to be a looooonnnnnngggg wait tonight..
hopefully tomorrow brings some cheer, else i am not sure what to do next...
gave up on a job offer last year to focus on my MBA aspirations...

Hopefully you'll get in. If you get waitlisted or denied though, it's not too late to apply to Anderson. I really only have great things to say about their program and the other students there. They're my second choice, but it's a great school. Professionally I keep running in to their alumni too. The last two principles hired at my firm are anderson alums.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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01 Feb 2013, 10:15
1
KUDOS
For everyone who are admitted already or might be put in WL today...
Upcoming chats:
Prospective Applicants: Join us for an Application Q&A Chat on Tuesday, March 5 at 12:30pm (PST).
Round 1 Waitlisted Applicants: If you were waitlisted during Round 1, please join us for a Waitlist Chat on Thursday, February 7 at 12:30 (PST). This chat is password protected.
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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05 Feb 2013, 09:38
1
KUDOS
and be relaxed, the interview is quite conversational.

Hope this helps.

mutemath83 wrote:
Hi,
I just joined GMATClub.
Congratulations to those who've been admitted!

Haven't had a chance yet to scour all the posts but this seems like an active thread.

I applied in R2 and I've been invited to an interview. Any tips on how to go about preparing for the interview? What questions to expect?, etc..

Cheers!
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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05 Feb 2013, 15:02
1
KUDOS
mutemath83 wrote:
Hi,
I just joined GMATClub.
Congratulations to those who've been admitted!

Haven't had a chance yet to scour all the posts but this seems like an active thread.

I applied in R2 and I've been invited to an interview. Any tips on how to go about preparing for the interview? What questions to expect?, etc..

Cheers!

As others have said, know your resume, know what you want out of an mba, what you want to do in the future, and why you want to go to Haas. Be yourself and try to keep it light. If you look earlier in the thread, some people posted the questions they were asked.

Good luck.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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05 Feb 2013, 15:50
1
KUDOS
yaank216 wrote:
Hi - first time poster here, but have been following this thread for awhile. Am a R2 applicant and invited for an interview. I read the other posts regarding the interview questions - do you think the interviewers will ask the same questions going forward? Seems as if R2 and R3 applicants would have an unfair advantage. Thoughts?

There are other websites you can use to look up questions from previous years. All but one of the questions I got were the same that they had previously used. It's a pretty straight forward interview. They're just trying to see that you know what you want and can talk to someone you haven't met before without a problem. Relax and be yourself. If they want you, they want you. If not, there's nothing you can do about it.
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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22 Feb 2013, 09:12
1
KUDOS
amylicious73 wrote:
@kris610: Not yet - I'm still impatiently eagerly awaiting my interview invite

@amylicious73 Hang in there. The decision date is more than a month away. I'm sure you will get invited. Use the time to know yourself better. Trust me, the more you know about yourself the better you will do in the interview.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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23 Feb 2013, 21:00
1
KUDOS
kris610 wrote:
amylicious73 wrote:
@kris610: Not yet - I'm still impatiently eagerly awaiting my interview invite

@amylicious73 Hang in there. The decision date is more than a month away. I'm sure you will get invited. Use the time to know yourself better. Trust me, the more you know about yourself the better you will do in the interview.

More than anything, know why you want an MBA, specifically an MBA from Haas. Also, be able to explain why you have changed jobs. If you haven't, be able to explain why you've stayed at a company for as long as you have.
Senior Manager
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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25 Feb 2013, 17:18
1
KUDOS
riskall wrote:
Dude....hope I can get in...I am assured of a study partner in Seattle that way

well, good luck. Now that I have a seat, I can truthfully say I'm rooting for all of you guys

If you do get in, don't take the statistics class through Berkeley Extension. God that thing is worthless.
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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28 Feb 2013, 17:34
1
KUDOS
kalips wrote:
Hi all,
I am new to this thread.
Congrats to all who made it to the EWMBA program and good luck to all aspirants.
My profile is Male/Semiconductors/700/7yrs/R3.
I am preparing the essays and have the following questions

First - Are there only three essays this year? (2 short essays and 1 main essay)
Second - For essay no. 2
2. a. What are your short term (3 to 5 years) and long term (10 + years) career goals?
b. How have your professional and personal experiences prepared you to achieve these goals?
c. Describe your plan to meet these goals. (250-500 words)
Does it mean that each part has to be 250-500 words ?

Hi Kalips,

The essay requirement for Fall 2013 is as follows:

Fall 2013 Short Answer Essay Questions
1. At Berkeley-Haas, the following four Defining Principles describe our unique culture and are exemplified in our student body. Please list one of the following principles and give a specific example(s) of how you have exemplified this in your life. (250-500 words) Please refer to the Haas website for more detailed descriptions of these Defining Principles:

A. Question the Status Quo
B. Confidence Without Attitude
C. Students Always
D. Beyond Yourself

2. a. What are your short term (3 to 5 years) and long term (10 + years) career goals? b. How have your professional and personal experiences prepared you to achieve these goals? c. Describe your plan to meet these goals. (250-500 words)

Fall 2013 Main Essay Question
Please tell us about yourself and your background. The goal of this essay is to get a sense of who you are, rather than what you have achieved professionally. You may include information about your family, where you grew up, your interests, or any other people or experiences that have influenced you. (1,000 word maximum)

The ENTIRE goals essay should be 250-500 words total, not each part. Good luck!
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Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants [#permalink]

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14 Mar 2013, 09:24
1
KUDOS
Kenny0929 wrote:
Folks,

I am a waitlisted R1 candidate. I am still deciding where to complete the Statistics Pre-Req. Couple of options:
1. Haas Data and Decisions Workshop: $1000 2. A class at De-Anza: ~$200

Not sure if taking the workshop is really any different from the class at De-Anza. However, in the grand scheme of things ($120k),$800 shouldn't be a big deal. But, would love to know the pros and cons. Could someone please pitch in?

Thanks!

Hi Kenny,
I'm currently a first year student in the program. I was just thinking about how I was on this board all the time last year and thought see how things are going for this year's applicants. I thought I'd offer some help since as a fellow waitlister I felt that I had less info than those that are accepted (the accepted people have a facebook group where they discus this sort of thing).

If you have ever taken any statistics course I recommend studying up and taking the waiver exam. Kahn academy and Hank Ibser youtube videos are a good resource. The waiver exam is tough but a lot of people passed it last year. If you don't pass you still have time to sign up for the Data and Decisions workshop starting in June. The people who took it last year said it was tough, but they learned a ton and the professor who taught it last year is awesome. One of my favorites so far.

I was a R2 applicant who was waitlisted and got in with R3 so don't lose hope. Some people were on the waitlist from R1-R3 and were accepted in the end. Good luck!
Re: Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants   [#permalink] 14 Mar 2013, 09:24

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# Haas (UC Berkeley) EWMBA 2013 - Calling All Applicants

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# Smarter contracts thanks to Delphi (part 1/2)

Delphi is the successor to the Carthage protocol. Delphi’s main difference from Carthage is that gas costs are lower, so that smart contracts can compute more before hitting the Delphi/Carthage per-operation gas limit of 1,040,000 gas units (gu).

In this post we quantify the difference that Delphi’s lower gas costs will make:

• We start with a description and justification of the Michelson gas model; and then
• we showcase the expected gains for some smart contracts chosen to illustrate the Delphi model’s advantages.

Measuring the gas gains for real-world smart contracts will be the topic of another post.

# 1. An overview of the Michelson gas model

To recap: gas limits guarantee that block validators only need a fraction of the time interval between blocks to validate a new block.

The exact fraction depends on the speed of the node’s hardware. Tezos tries to be inclusive, so we want even slow hardware to be able to sync the chain in real time.

As we wrote in our last gas post:

overestimating gas costs prevents developers from writing more interesting contracts, while underestimating these costs leads to possible attacks. It is important to get this right.

In fact, there are two ways to allow more computation in a block:

1. improve the performance of block validation and decrease the gas costs accordingly, or
2. refine the gas model when it overestimates gas costs.

For the Delphi proposal, we did both.

## 1.1 Execution steps of a smart contract call

A Tezos smart contract is a type of Tezos account consisting of:

1. the smart contract balance,
2. the smart contract code, which is executable code in the Michelson programming language, and
3. the smart contract storage, used to save the contract’s state between calls.

A transfer calls a smart contract by invoking it along with a parameter. The Tezos protocol then executes1 the smart contract code, passing it two inputs:

1. the parameter, and
2. the contract’s current storage.

Outputs after execution are:

• updated storage, and
• a (possibly empty) list of operations to be added to the queue of pending operations.2

The Tezos protocol uses three distinct formats to represent Michelson scripts and values, listed here in increasingly higher levels of abstraction:

1. Raw byte sequences: is how data is stored on disk, or in operation payloads (in particular, parameters are stored as raw byte sequences).
2. Micheline: the Micheline format is protocol-independent (think: XML or Json for Michelson code) and portable across protocol versions. Micheline data has a tree-like structure so it is easier to manipulate than byte sequences; but it is still untyped.
3. The Michelson internal representation: this format is specific to each version of the Tezos protocol. Michelson expressions written in this format are guaranteed to be well-typed. It is the only format known to the Michelson interpreter.

When a Tezos smart contract is called — either due to some initial call to it, or as a consequence of working through a queue of accumulated operations e.g. from step 8 below — the Tezos protocol performs the following steps:

1. Read the contract’s script and storage from disk, as raw byte sequences (the parameter is already in memory).
2. Deserialise (convert) the script, storage, and parameter to Micheline.
3. Convert Micheline to the internal representation. The protocol code calls this step parsing; the command-line client calls it type-checking (since type errors might be thrown).
4. Interpret (execute) the smart contract using as inputs its storage and the parameter. At the end of this step, we obtain the updated storage, and a list of new operations.
5. Unparse updated storage — convert from the internal representation to Micheline.
6. Serialise this Micheline expression — convert it to a byte sequence.
7. Write the byte sequence to disk.
8. Queue the list of new operations to apply.
9. Loop to 1, until the operation queue is empty.

## 1.2 Limiting execution, with gas

Each of the execution steps above could take arbitrary time, so to guarantee that nodes can check the validity of operations in reasonable time, the protocol imposes a hard limit on computation and considers as invalid any operations that exceed it. This limit cannot just be a timeout: then fast nodes would have different valid operations than slower ones — and the network would not reach consensus.

Instead, we rely on gas; a hardware-independent abstraction of the time needed to validate operations that is built in to the Tezos protocol.

Here are the usual reasons we consume gas (relative weights depend on the smart contract being executed):

2. deserialisation,
3. parsing,
4. interpretation, including a fixed per-operation gas cost,
5. unparsing,
6. serialisation, and
7. writing to disk.

Gas prevents overlong operations, so the chain’s security depends on good estimates of how long each task above will take:

• An underestimate is a security risk because it makes it cheap to launch a denial-of-service attack on a node, using a smart contract.
• An overestimate will unduly restrict the complexity of the smart contracts that can be run, which may annoy users but is not a security risk.

Thus, when we launched the Betanet, our gas constraints were deliberately overestimated, intended to be decreased later by protocol amendments.

## 1.3 Estimating gas costs (and getting it right)

But how far can we safely decrease gas costs in practice? To quantify this, we performed two kinds of benchmarks:

• Macro benchmarks fill a block with operations designed to stress some particular source of gas consumption (e.g. computation, or disk accesses).
• Micro benchmarks measure the time it takes to execute functions of the protocol on random inputs (of various sizes). This helps build a predictive model of the time taken by the function, so that the gas cost can precisely reflect it.

In the previous Athens and Babylon amendments we adjusted the gas model:

For the Athens proposals, we did macro benchmarks to refine the relative costs of disk accesses and computations. These benchmarks showed that disk accesses were too expensive compared to the other costs and we divided the relative cost of disk accesses by 2 to reflect this.

For the Babylon proposal, we micro-benchmarked the interpretation time of most instructions on random data of various sizes and interpolated cost models to all the benchmarked instructions. This led to a significant decrease of the interpretation costs of most instructions.

For the current Delphi proposal:

• We developed a generator of well-typed Michelson code of arbitrary size and used it to micro-benchmark serialisation and parsing functions.
• We optimised the parsing functions.
• We optimised the Michelson interpreter.
• We updated the Babylon instruction-per-instruction benchmarks to reflect the new optimisations of the interpreter and reduced the interpretation costs accordingly.
• We benchmarked disk accesses on modern hardware and revised the corresponding gas model.

The modifications of the gas model brought by the Delphi proposal are documented in the following merge requests:

Now, we will measure the changes in gas consumption for contracts that are intensive in one of the components and not the others.

# 2. Theoretical limits

The following Michelson scripts are not realistic; they are designed to measure the gas gains for the Delphi proposal:

## 2.1 Gas costs for disk access (read / write)

To avoid deserialisation and parsing costs, we read and write lots of data of type bytes. Before reaching the gas limit per operation, we hit another limit defined by the protocol: the storage increase limit.

A single transaction may increase the contract storage by no more than 60kB (1kB = 1000 bytes) — we can build larger byte sequences dynamically; see later. To write more than 60kB in a single transaction we must also remove data in the same transaction.

Here is our Michelson script for a smart contract to stress the disk limits:

# Script io.tz
storage (pair (nat %counter) (big_map %tank nat bytes));
code
{
UNPAPAIR;
IF_LEFT
{

DROP;

PUSH bytes 0x00;
# 15 DUP; CONCAT
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;
DUP; CONCAT;

SOME; SWAP; DUP; DUG 3; UPDATE; SWAP;

PAIR;
}
{
IF_LEFT
{
# %write(n : nat): store 2^n bytes in the big_map

# First clear the big_map to decrease the storage size diff
DUG 2;
RENAME @counter;
SWAP;
PUSH @index nat 0;
PUSH bool True;
LOOP
{
DUP; DIP { NONE bytes; SWAP; UPDATE };
DUP @index; DUP @counter 4; CMPGE
};
DROP; SWAP; DROP; SWAP;

# do n DUP; CONCAT
DIP { PUSH bytes 0x00 };
INT;
DUP;
GT;
LOOP
{
PUSH nat 1; SWAP; SUB;
DIP {DUP; CONCAT};
DUP; GT
};
DROP;
SOME;
PUSH nat 0;
UPDATE
}
{
# read(_ : unit): read the bytes that have been stored by %write
DROP 2;
DUP;
PUSH nat 0;
GET; DROP
};
PUSH nat 0; PAIR
};
NIL operation;
PAIR
}

The script io.tz above declares a storage of type pair (nat %counter) (big_map %tank nat bytes). The tank big map serves as a data tank which we will fill in several transactions, and then empty all at once to get a lot of writing rights. tank is expected to contain at index i 32KiB (1KiB = 1024 bytes) of zeros if i is smaller than the counter counter, and nothing otherwise. This script features three entrypoints:

• add32K inserts data into the tank.
It adds 32KiB of data (note that 64KiB would exceed the storage size diff limit) in the first empty slot in the big map, and increments the counter to maintain the invariant.
• write n empties the tank.
It puts None in all big map entries from $$0$$ to the value of the counter, resets the counter to $$0$$, and puts a byte sequence of size $$2^n$$ at the first position in the big map.
• read accesses the first position in the big map and does nothing with it.
This entrypoint returns the storage unchanged.

We use the script io.tz as follows:

1. We originate it on a default storage Pair 0 {}; and
2. we repeatedly call the add32K entrypoint to insert enough data in the tank; and
3. once the storage is big enough (experimentally, 64 calls to add32K are enough), we call write with the largest parameter that the gas limit allows; and finally
4. we call read.

For the read entrypoint, thanks to the --trace-stack option of the client, we can compute the gas consumption of the GET instruction alone, so the gas consumption caused by reading the disk is well-isolated from other gas consumptions.

• In Carthage, the largest n we can pass the write entrypoint is n=15, which hence writes 32KiB ($$2^{15}$$B) and consumes 535741 gu (thus slightly more than half the per-operation gas limit of 1,040,000 gu). Reading back these 32KiB costs approximately a third of the gas limit (the gas consumption of the GET instruction is 344481 gu).
• In Delphi, we can reach n=21 which writes 2MiB ($$2^{21}$$B) and also consumes exactly 555330.160 gu (again slightly more than half the gas limit, which is the same as Carthage’s); the GET instruction of the read entrypoint then consumes almost as much gas (520045.437 gu).

In summary, comparing the gas costs in Carthage and Delphi:

• Writing large pieces of data costs about 62 times less (a 98.4% saving).

Quantifying the real-world impact of these cost reductions on practical Delphi usage will be the topic of the future blog post — but we can note here that this is clearly a significant reduction.

## 2.2 Gas costs for parsing code and data

Parsing costs are easy to decorrelate from the other sources of gas consumption thanks to the tezos-client typecheck data and tezos-client typecheck script commands that report exactly the amount of gas consumed at parsing. The Delphi gas model for parsing costs typically 40 times less than Carthage’s one.

To assess typechecking costs, we construct a synthetic script big_script.tz, which contains 4000 DUP and 4000 DROP. We then typecheck this script via the tezos-client typecheck script command.

This costs 248168 gas units under Carthage but only 6003.655 gas units under Delphi; so in this example the Dephi gas model costs 41.37 times less.

## 2.3 Gas costs for contract interpretation

Gas costs in the Michelson interpreter include

• costs for instruction interpretation as discussed — and also
• overhead costs in the Michelson interpreter due to the gas accounting system itself.

In Delphi we have optimised both. To evaluate the gains due to the Michelson interpreter optimisations in Delphi, we consider the scripts of two contracts:

### 2.3.1 Gas costs for constructing a large data structure

Let’s first consider a contract that builds a huge list and does nothing with it:

# Script big_list.tz
parameter nat;
storage unit;
code
{
CAR;
INT;
NIL unit;
UNIT;
CONS;
SWAP;
DUP;
GT;
LOOP
{
PUSH nat 1; SWAP; SUB;
SWAP;
DUP; ITER {CONS};
SWAP; DUP; GT
};
DROP 2;
UNIT; NIL operation; PAIR
}

When the contract big_list.tz receives n as parameter, it:

1. Builds a list unit that initially contains a single element.
2. Iterates n times in a loop that concatenates the list with itself (DUP; ITER{CONS}).
3. Empties the stack (DROP 2).

So this contract pays gas for building a list of length 2^n, and only for that.

• In Carthage we can set at most n=20 and this consumes 996143 gas units.
• In Delphi, the same contract with n=20 consumes 230406 gas units.

Thus, the cost in Delphi is 4.32 times less.

### 2.3.2 Gas costs for arithmetic

Arithmetic in Michelson is implemented using the Zarith arbitrary-precision library, a well-optimised OCaml wrapper of the GMP C library. Neither Zarith nor GMP has been modified in the development of Delphi and the cost models for arithmetic functions have been quite precise since Babylon, so there’s little hope for further optimisation in Delphi, for smart contracts that are mostly arithmetic computation.

To measure this, we wrote a simple loop-based factorial in Michelson:

# Script arith.tz
parameter nat;
storage unit;
code
{
CAR;
PUSH @acc nat 1;
PUSH @i nat 2;
DUP;
DUP 4;
CMPGE;
LOOP
{
DUP;
DIP {MUL @acc};
DUP;
DUP 4;
CMPGE;
};
DROP 3; UNIT;
NIL operation; PAIR
}

As in the big_list.tz example, the result of the computation is not stored, to isolate the cost of the computation from the cost of storing the result.

The biggest parameter that can be sent to this contract within the gas limit in Carthage is exactly 6400. With this parameter,

• 1039686 gas units are consumed in Carthage and
• 389054 gas units are consumed in Delphi.

Thus, the factorial script costs 2.67 times less in Delphi.

## 2.4 Gas costs for inter-contract calls, in two parts

### Part 1 of 2: Recursion

In Carthage, applying an operation has a minimal cost of 10 kgu (1 kgu = 1000 gu). In Delphi, the minimal cost is 1 kgu, thus ten times smaller. As we shall see below when we look at the self_recursion.tz script, this minimal cost is no longer a dominating cost for contracts that perform a lot of calls.

A simple way to test how many contract calls can be achieved in Carthage and in Delphi is to write a recursive contract that calls itself n times and then stops: it takes a number n as parameter and stops if n is 0, and calls itself on n-1 otherwise.

Here is the corresponding Michelson script:

# Script self_recusion.tz
parameter int;
storage unit;
code
{
UNPAIR; DUP; EQ;
IF
{ DROP; NIL operation; PAIR }
{
PUSH int 1; SWAP; SUB;
SELF; PUSH mutez 0; DIG 2; TRANSFER_TOKENS;
NIL operation; SWAP; CONS; PAIR
}
}

• In Carthage, we measured that each recursive call of self_recursion.z consumes 13178 gas units, so the largest n we can send to this contract within the protocol-set per-operation gas limit (1,040,000 gu) is n=77.

• In Delphi, each recursive call of this contract only consumes 2871.559 gas, so the largest n we can send to this contract within the per-operation gas limit (identical to Carthage’s) is n=361.

We see that in Carthage the gas costs of self_recursion.tz are dominated by the 10 kgu cost of operation application, which represents about 3/4th of its total gas consumption. In Delphi, it only represents about 1/3rd of the total.

### Part 2 of 2: A chain of calls

Calling a contract (recursively or otherwise) incurs a non-trivial gas cost, corresponding to loading, deserialising, and type-checking the contract as well as checking that the parameter to the call has the right type (cf. discussion above).

Since typical inter-contract interactions are not recursive, we concentrate here on non-recursive calls.

To test non-recursive contract calls, we build a chain of smart contracts. Each contract calls the next until we reach the last contract in the chain, which then originates a new contract to grow the chain. More precisely:

• The contracts in the chain have two possible states called forwarding and final.
• In forwarding state, the contract
• casts it to contract unit (the type of contracts expecting no parameter), and
• calls it.
• In final state, the contract
• originates a copy of itself with an initial storage in final state,
• stores the address of the newly-originated contract, and
• switches to forwarding mode.

Unfortunately, there is no instruction in Michelson to originate a copy of oneself; the only way to originate a contract from Michelson is with the CREATE_CONTACT instruction, which expects as static argument the full script of the contract to originate. Therefore, to originate a copy of the current contract, we cannot use CREATE_CONTRACT directly in the contract script: there is no finite script satisfying the equation script = { ...; CREATE_CONTRACT script ...; ... }. We need to untie this recursive3 equation and solve it at run-time, by either placing part of the script in the storage (using a lambda) or in the script of another contract.

We choose the former option (to put it in the storage) and leave the motivated reader to implement a solution based on the latter as an exercise.

The lambda that the contract stores needs to return both the origination operation and the address of the newly created contract, so its return type is pair address operation. As input, it needs some data to initialise the storage of the freshly-originated contract, which is basically the lambda itself in serialised form.

The trick to solve the recursive equation mentioned above is to have the lambda deserialise its own code using the UNPACK instruction — so the input type of the lambda is bytes and its code starts with UNPACK (lambda bytes (pair address operation)) — followed by code to originate the contract using the CREATE_CONTRACT instruction.

The complete script of the contract used by each link in the call chain is:

# Script link_contract.tz
parameter unit;
code
{ NIL operation;
SWAP;
CDR;
IF_LEFT
{
# in %final mode, call the stored lambda on itself
DUP ;
PACK;
EXEC;
UNPAIR;
DIP{CONS}
}
{
# in %forward mode, call the stored address
DUP;
CONTRACT unit;
ASSERT_SOME;
PUSH mutez 0;
UNIT;
TRANSFER_TOKENS;
SWAP;
DIP{CONS}
};
# in both cases, we end in %forward mode
RIGHT (lambda bytes (pair address operation));
SWAP;
PAIR
}

And its initial storage is:

Left { UNPACK (lambda bytes (pair address operation));
ASSERT_SOME;
PUSH mutez 0;
NONE key_hash;
SWAP;
PAIR}

• In Carthage, the cost of each transfer in this chain of calls is 27817 gu. We can build a chain of 36 transfers and one origination before reaching the per-operation limit of 1,040,000 gu.
• In Delphi, the cost for each transfer is about 4779 gu. We can build a chain of 217 transfers and one origination before reaching the limit of 1,040,000 gu.

Thus, Delphi lets us grow the chain by a factor of almost 6.

# Conclusion

The Delphi protocol reduces gas costs and allows more complex smart contracts to be deployed and executed. The gas gains vary depending on the source of gas consumption. We measured this using scripts tailored to reach the gas limit in different ways. The results in short are:

Gas source Carthage consumed gas Delphi consumed gas Ratio
Writing to disk 535741 gu / 32 KiB 555330.160 gu / 2MiB 61.7
Reading from disk 344481 gu / 32 KiB 520045.437 gu / 2MiB 42.4
Parsing 248168 gu 6003.655 gu 41.4
Computation 996143 gu 230406.664 gu 4.32
Arithmetic 1039686 gu 389054.329 gu 2.67
Recursion 13178 gu 2871.559 gu 4.59
Inter-contract call 27817 gu 4779.106 gu 5.82

So to sum up:

1. Delphi enjoys a significant reduction in parsing costs: thanks to the refinement of the gas model for parsing, most contracts should see their parsing gas reduce by a factor of about 40, compared to Carthage, making it more practical to deploy and operate on larger contracts.
2. Similarly the cost of large disk accesses (I/Os) is reduced by a factor of about 60 for the largest disk writes.
3. Together, our improvements make inter-contract calls cheaper by a factor of 6 in our tests.
4. Improvements in contract interpretation costs exist though they are less striking because the cost model was quite precise already in Babylon (the version preceding Carthage). Yet, even here we can see quite significant improvements thanks to Delphi’s optimisations in the gas costs of the Michelson interpreter’s gas accounting system.

In a future blog post, we will measure the gas gains observed on a collection of real-world contracts that are either already popular on mainnet or about to be launched.

1. Executes” here means “interprets”, in the sense of “an interpreter”.

2. Returning a (non-empty) list of operations is sometimes also referred to as emitting or applying them.

3. We distinguish between a recursion when a lambda calls itself, and a recursive contract call when a contract calls itself (with all the costs this entails). Here, we’re dealing just with the first kind of recursion.

format: plain


text:
# Read High voltage from PIC16F [duplicate]

I have planned to build a circuit to display voltage and time value using PIC16F877A micro controller.To do this i tested the circuit using Proteus software as i attached here. It can display up to 5V.

my question is can i read up to 300V using this micro controller?(I planned to use LR8N3G voltage regulator to give input voltage to PIC).will it damage the PIC? If so how can I read high voltage from this?

## marked as duplicate by dim, JRE, pipe, Elliot Alderson, Warren HillFeb 7 at 10:58

• What's the lower limit of the voltage to be read? If it's too low (e.g. 1V) then a simple voltage divider may not work. I mean, you may need to build a "smart" divider (i.e. activates/deactivates divider networks based on the input voltage). It also depends on whether the voltage is AC or DC. – Rohat Kılıç Feb 5 at 4:46

$$\begin{split} &\frac{V_\mathrm{in}} {Z1 + Z2} \cdot Z_2 = V_\mathrm{out}\\ \\ &\frac{(V_\mathrm{in} - V_\mathrm{out})^2}{Z_1} =\text{ Power dissipated by }Z_1 \end{split}$$
I suggest choosing $$\Z_1\$$ first.


text:
# Least Mean-Squares Equalizer

By Joseph D. Gaeddert on December 29, 2018

This tutorial provides an overview of a very simple fininite impulse response least mean-squares equalizer simulation. This is part of my "DSP in 50 lines of C" series.

// liquidsdr.org/blog/lms-equalizer/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <complex.h>

int main() {
unsigned int M           = 1 << 3;  // phase-shift keying mod. order
unsigned int num_symbols = 1200;    // number of symbols to simulate
unsigned int w_len       = 13;      // equalizer length
float        mu          = 0.05f;   // equalizer learning rate
float        alpha       = 0.60f;   // channel filter bandwidth

// create and initialize arrays
unsigned int  n, i, buf_index=0;
float complex w[w_len];             // equalizer coefficients
float complex b[w_len];             // equalizer buffer
for (i=0; i<w_len; i++) w[i] = (i == w_len/2) ? 1.0f : 0.0f;
for (i=0; i<w_len; i++) b[i] = 0.0f;

float complex x_prime = 0;
for (n=0; n<num_symbols; n++) {
// 1. generate random transmitted phase-shift keying symbol
float complex x = cexpf(_Complex_I*2*M_PI*(float)(rand() % M)/M);

// 2. compute received signal and store in buffer
float complex y = sqrt(1-alpha)*x + alpha*x_prime;
x_prime = y;
b[buf_index] = y;
buf_index = (buf_index+1) % w_len;

// 3. compute equalizer output
float complex r = 0;
for (i=0; i<w_len; i++)
r += b[(buf_index+i)%w_len] * conjf(w[i]);

// 4. compute 'expected' signal (blind), skip first w_len symbols
float complex e = n < w_len ? 0.0f : r - r/cabsf(r);

for (i=0; i<w_len; i++)
w[i] = w[i] - mu*conjf(e)*b[(buf_index+i)%w_len];

// print resulting symbols to screen
printf("%8.3f %8.3f",   crealf(y), cimagf(y)); // received
printf("%8.3f %8.3f\n", crealf(r), cimagf(r)); // equalized
}
return 0;
}

## Overview

Wide-band single-carrier systems commonly suffer from distortion across the modulated band, often caused by imperfect transmit or receive filters in hardware or multi-path channel effects. This manifests as inter-symbol interference in the received constellation causing an increase in errors if left uncorrected. Equalization attempts to remove these effects by dynamically adjusting the coefficients of a filter to minimize some cost function, often the mean-squared error. With a good equalizer the linear effects of the channel can be virtually removed. Non-linear effects such as noise, interference, and clipping can be mitigated if the equalizer is designed properly, but only up to a limit.

Figure [equalizer]. The results of this simulation with the symbols before (left) and after (right) equalization.

For the sake of simplicity, we will operate at complex baseband, sampled at one sample per symbol. In practice operating at a higher sample rate is preferred because the equalizer can prevent aliasing before down-sampling, further reducing distortion. The figure above demonstrates the input and output symbols simulated in the above source code.

## Description of Operation

Suppose a transmitted symbol sequence $$\vec{x} = [ x(1), x(2), \ldots, x(N) ]$$ passes through an unknown and time-varying channel. The receiver observes a sequence of symbols $$\vec{y} = [ y(1), y(2), \ldots, y(N) ]$$ which are correlated due to the channel filter and noisy due to an additive random process. The adaptive linear equalizer attempts to use a finite impulse response (FIR) filter $$\vec{w}$$ of length $$p$$ to estimate the transmitted symbols using only the received signal vector $$\vec{y}$$ and partial knowledge of the known data sequence $$\vec{x}$$ . Several methods for estimating the weights in $$\vec{w}$$ are known in the literature, and typically rely on iteratively adjusting $$\vec{w}$$ with each input though a recursion algorithm. The method is described in the documentation on equalizers in liquid for both the least mean-squared (LMS) and recursive least-squared (RLS) algorithms. Due it its simplicity and relatively low complexity, this post will focus on the LMS equalizer.

The least mean-squares (LMS) algorithm adapts the coefficients of the filter estimate using a steepest descent (gradient) of the instantaneous a priori error. The filter estimate at time $$n+1$$ follows the following recursion

$$\vec{w}_{n+1} = \vec{w}_{n} - \mu \vec{\nabla}_n$$

where $$\mu$$ is the iterative step size, and $$\vec{\nabla}_n$$ the normalized gradient vector, estimated from the error signal and the coefficients vector at time $$n$$ .

Often in practice the receiver has no knowledge of the transmitted sequence $$\vec{x}$$ and so an estimate must be made for the gradient vector at each time step. Furthermore, the receiver might have no knowledge of even the transmitter's modulation scheme and so the receiver must make an estimate completely in the blind. In this situation a relatively good error value is just the deviation from the equalizer output from its nearest point on the unit circle:

$$e(n) \triangleq r(n) - \frac{r(n)}{|r(n)|}$$

where $$r(n)=[y(n-p+1),\ldots,y(n)]\cdot\vec{w}^H$$ is the output of the equalizer at time $$n$$ . This is effectively saying that the equalizer should have produced a symbol that has the same phase as $$r(n)$$ but lies on the unit circle. From this, a reasonable estimate of the error gradient is simply the last $$p$$ received symbols scaled by the conjugate of this complex error signal

$$\vec{\nabla}_n \approx e^*(n) [y(n-p+1),\ldots,y(n)]^T$$

## Coding it up

The source code above is organized as usual with simulation options at the top, followed by value initialization and the main loop. Within the loop there are five steps for simulating the equalizer:

1. The time index is set to $$n$$ and the transmitter generates a random $$M$$ -ary phase-shift keying symbol $$x(n) = \exp\{j2\pi k/M\}$$ for $$k \in \{0,1,\ldots,M-1\}$$
2. The received symbol $$y(n)$$ is computed from the channel filter (in this case a single-pole recursive filter for simplicity) and the receiver stores it at the end of its buffer, $$\vec{b}_n = [ y(n-p+1), \ldots, y(n) ]^T$$
3. The receiver uses its current set of weights $$\vec{w}_n$$ to compute the output of the equalizer $$r(n) = \vec{b}_n^T \vec{w}_n$$
4. A blind estimate of the error signal is computed by finding the vector between the equalizer output and the closest corresponding value on the unit circle, $$e(n) = r(n) - r(n)/|r(n)|$$
5. The equalizer weights are adjusted according to the estimated error signal from the equalizer otuput and the last $$p$$ received symbols, viz $$\vec{w}_{n+1} = \vec{w}_n - \mu e^*(n) \vec{b}_n$$

Compile equalizer.c above and run the program with:

gcc -Wall -O2 -lm -lc -o equalizer.c -o equalizer
./equalizer

...which should produce the following output.

0.447   -0.447   0.000    0.000
0.716    0.179   0.000    0.000
0.877    0.555   0.000    0.000
0.526    0.965   0.000    0.000
0.316    1.212   0.000    0.000
0.822    0.727   0.000    0.000
1.126    0.436   0.447   -0.447
0.675   -0.371   0.716    0.179
...
0.627   -0.245   0.005   -1.001
-0.257   -0.147   0.710   -0.700
0.293   -0.535   0.703    0.707
0.623   -0.768   0.006   -0.994
0.374   -1.093   0.700    0.709
0.672   -1.103  -0.700   -0.709

The first two columns are the real and imaginary components of the input symbols, respectively. The third and fourth columns are the real/imag of the output. Plotting these symbols gives the figure near the top of this post.

## Considerations

This is a blind estimation method. What happens when the modulation scheme isn't phase-shift keying, but quadrature amplitude modulation ? As it turns out, this blind estimator works quite well for most digital modulation types provided that the underlying data are sufficiently random. Of course the performance is not as good as a decision-directed method (where knowledge of the underlying modulation scheme is known), or when a known transmitted sequence is used. Furthermore, the blind estimation method used here cannot compensate for unknown phase offsets.


text:
Zuletzt geändert: Mo, 19.02.2007

# «K12/K13» 31. Hausaufgabe.latex «PDF»,«POD»

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\author{Ingo Blechschmidt}

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\begin{document}
\title{The infinite amount of information'' provided by cable TV and the Internet -- a blessing or a curse?}
\date{15th February 2007}

\maketitle

\tableofcontents

%

% linenum=8 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)

\section*{Introduction}

Television and the Internet -- or media in general -- play a downright predominant role in our modern society. Television receivers exist in 95 percent of all German households and 98 percent of American households,{} according to \cite{E31WikiDeFernsehenInDeutschland} and \cite{E31WikiDeFernsehenInDenUSA} respectively; 68 percent of German\'{}s adults have direct access to the Internet (\cite{E31Heise68}).

Because of their plangent distribution,{} consequences caused by television and the Internet have to be reflected upon very seriously -- much more seriously than would be needed in a society not permeated by medias.

In the following,{} I\'{}ll ponder the question whether the infinite amount of information'' provided by television and the Internet are to be considered a blessing or a curse. This cannot be decided in general,{} of course; instead I\'{}ll give several arguments for both views.

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\section{Infinite amount of information'' provided by television and the Internet as a curse}

This section lists arguments for the view that the infinite amount of information'' provided by television and the Internet is a curse. It is divided in arguments concerning the quality of the obtainable information,{} the accessibility of television and the Internet,{} and miscellaneous other arguments.

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\subsection{Quality of the obtainable information}

To gauge the relevance of the infinite amount of information'' obtainable,{} one should first contemplate the quality of the information broadcasted on television and downloadable on the Internet.

% linenum=40 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsubsection{Unintentional misinformation}

The most common cause of wrong information on television and the Internet is probably constituated by unintentional oversights. As it is acknowledged that it takes approximately ten years to become an expert on any given topic \symbol{91}unfortunately I have a lost the reference to a study supporting this statement],{} information is often compiled by laymen who have only a rough knowledge on the relevant area.

This argument is often used against Wikipedia,{} rendering Wikipedia as full of errors. Other examples include the presentation of scientific relations in so-called popular science''; these explications are often simplified to a great extent -- one popular misconception of natural sciences,{} namely that natural sciences Explain The World instead of just providing accurate (but in no case exact or true!{}) models,{} forms the root of the discussions on Intelligent Design in the USA.

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\subsubsection{Unrepresentative information}

The quality of the information provided by television and the Internet is further downgraded by the unrepresentative assembly of the corresponding authors: The opinions and views broadcasted and displayed on television respectively the Internet are influenced by the views of the persons in charge.

This problem surfaces especially on the Internet -- the people who publish on the Internet obviously belong to the group of people who have the ability to publish on the Internet. This means that the views of,{} say,{} the typical 90-year-old grandparents are under-expressed.

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\subsubsection{Directed disinformation}

Directed disinformation has the potential to degrade the information quality in most severe ways. The sources of such disinformation range from companys which exaggerate'' facts about their products over politicians to whole countries which enact over a consolidated apparatus spreading targeted disinformation.

A prominent example of such directed disinformation is the actively enforced censorship in the People\'{}s Republic of China: If you search for Tiananmen'',{} the name of the place the 1989 massacre took place (in which several hunderds of people were killed \cite{E31WikiEnTiananmen}),{} Google Germany presents you with a host of pictures of tanks \cite{E31GoogleDeTiananmen}. By stark contrast,{} Google China shows pictures of smiling tourists \cite{E31GoogleCnTiananmen}.

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\subsection{Accessibility of the information}

The Internet introduces new technological barriers to the accessibility of the information. To access all the information of the Internet,{} one not only needs appropriate hardware (which,{} of course,{} costs money),{} an Internet provider free of censorship,{} and the physical abilities to use computers,{} but knowledge on using computers as well.

This means that certain groups of people are excluded -- for example older people who can\'{}t read computer screens or handle the keyboard or mouse appropriately and disabled persons.

Finding useful information on the Internet is further impeded by its vast size; it takes practice to develop the keen sense necessary to use search engines effectively.

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\subsection{Potential harm to children by pornographic content}

To the infinite amount of information'' retrievable on the Internet and broadcasted on television,{} pornographic content are a part of. It is believed that pornographic pictures and movie constitute the greatest part of all Internet traffic \cite{E31PornTraffic}. (But note that the amount of traffic as measured in (peta) bytes is not a good measure of the proportion of pornographic sites,{} as images and movies take up much more space (i.e.,{} bytes) than texts do.)

Considering the television programme broadcasted at night,{} one obtains similar impressions.

Barriers to pornographic contents on the Internet can be circumvented even by the average child in many cases,{} as it\'{}s technically challenging to automatically classify the raw information retrieved from the Internet as information with pornographic content -- computers do not (yet?{}) have access to the semantic level of information.

The few necessarily-not-perfect-but-deemed-to-be-sufficient tech\-ni\-ques to automatically block access to porn sites which exist today can easily be fooled.

% linenum=123 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsection{Sensory overload caused by the infinite amount of information''}

The probably most important problem caused by the infinite amount of information'' broadcasted on the 500-and-counting channels of television and retrievable on the Internet is probably the sensory overload intimately associated with the way television and the Internet are used.

Many studies show that in the so-called process of zapping'',{} in which individual channels are rarely watched for longer than a few seconds,{} the senses are overly stressed.

In the case of the Internet,{} the problem is slightly less severe,{} as active instead of passive use is necessary for the problem to manifest. Also,{} as websites used to be mostly visual-only,{} only the sense of sight was affected. With the increasing popularity of movie websites like YouTube \cite{E31YouTube},{} this last point has lost validity,{} unfortunately.

% linenum=141 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\section{Infinite amount of information'' provided by television and the Internet as a blessing}

The previous section outlined arguments for the view that the infinite amount of information'' of television and the Internet are a curse. As with any technology,{} down- and upsides coexist; in the following,{} I\'{}ll elaborate on some of the advantages of the infinite amount of information'' obtainable,{} with a slight focus on the role of the Internet.

I\'{}ll not mention that television with its \ensuremath{\text{500}^+} channels and the Internet with its millions of sites are superb examples of countermeasures against boredom.

% linenum=153 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)

One of the reasons for the wide-spread distribution of television and the Internet is certainly that they result in economic advantages. In societes governed by the principles of free market economy,{} economic considerations carry a lot of weight.

% linenum=161 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsubsection{Economic advantages through the use of television and the Internet as means of distributing advertising material}

There exists a wide spectrum of possible types of advertising on television and the Internet. More encompassing than ads in printed media,{} thousands of targets can be reached very time- and cost-efficiently.

% linenum=167 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsubsection{Economic advantages through the possibiliy of efficient trans\unichar{173}ac\unichar{173}tions}

Many companies,{} especially companies which operate in the logistical sector,{} profit from the very efficient conductability of transactions attainable on the Internet. Commiting and equating deals (i.e.,{} effectively rolling back) are matters of seconds; one can act to new information in a timely matter.

% linenum=174 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsection{Quality of the information obtainable}

Contrary to what I said above,{} the information broadcasted on television and receivable on the Internet is of a very high niveau -- presuming that one knows the right ruses to distinguish high-quality from low-quality information.

Wikipedia,{} for example,{} is a source of very high quality. Barring few problem areas,{} Wikipedia is factual and actual (attributes stemming from the encouraged possibility that anyone can improve Wikipedia),{} and attains a good structure by the extensive use of links.

Grassroot and citizen journalism is covered on so-called blogs: independent journalists can publish their results without pressure resulting from commercial and political interests as they often influence more regularly edited print media magazines. \cite{E31WikiEnCJ}

% linenum=191 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\subsection{Advantages -- blessings -- resulting from the decentral nature of the Internet}

These new movements profit from the technical difficulty the creation of a point of central control over the Internet would have.

Because of the Internet\'{}s decentral nature,{} it is infeasible that a single company or county could gain control over the entire Internet; thus the Internet is the ideal medium for guaranteeing the continued validity of one of the most fundamental human rights,{} namely the freedom of speech.

In addition to providing a great platform for asynchronous communication,{} i.e. the point in time of creation differs from the point in time of reading (mails,{} blogs),{} the Internet serves as the basis for a variety of real-time chat services.

Examples of serious uses of chats include real-time updates about the Gulf War in 1991 (an archive may be found at \cite{E31IRCGulf}) and live reports about the unstable situation in Moscow during the coup against Boris Yeltsin in 1993,{} disclosed directly by the affected people and not layered through several news agencies. \cite{E31IRCRT}

Finally,{} contemplated from an ideological point of view,{} one might have the belief that it\'{}s better that information is stored decentrally,{} accessible to everyone,{} instead of being property of a few rich millionaires and heads of states.

% linenum=217 filename=Inhalte//Englisch//Hausaufgaben//31. Hausaufgabe.pod (preprocessed)
\section*{Conclusion}

I remark that \textsl{in conclusio},{} the benefits of the infinite amount of information'' provided by television and the Internet outweigh the downsides. To a more complete report on this topic advantages and disadvantages of television and the Internet itself,{} not the infinite amount of information'' provided,{} would have to be considered.

Important parts of such an extended exposure to the topic would include: the social and sanitary consequences of daily use of television and the Internet; an \textsl{en detail} explication of threats emerging from the Internet (the corresponding buzzwords are phishing'' and cracking'') and risks for the Internet (including China\'{}s ongoing censorship as a political component and various technical difficulties arising from the continued exponential development of the world population).

\scriptsize
\begin{thebibliography}{50}
\bibitem{E31WikiDeFernsehenInDenUSA}
\url{http://de.wikipedia.org/wiki/Fernsehen_in_den_USA}
\vspace*{-0.5em}

\bibitem{E31WikiDeFernsehenInDeutschland}
\url{http://de.wikipedia.org/wiki/Fernsehen_in_Deutschland}
\vspace*{-0.5em}

\bibitem{E31WikiEnCJ}
\url{http://en.wikipedia.org/wiki/Citizen_journalism}
\vspace*{-0.5em}

\bibitem{E31WikiEnTiananmen}
\url{http://en.wikipedia.org/wiki/Tiananmen_Square_protests_of_1989}
\vspace*{-0.5em}

\bibitem{E31IRCGulf}
\vspace*{-0.5em}

\vspace*{-0.5em}

\vspace*{-0.5em}

\bibitem{E31Heise68}
\url{http://www.heise.de/newsticker/meldung/83774}
\vspace*{-0.5em}

\bibitem{E31IRCRT}
\url{http://www.mirc.com/irc.html}
\vspace*{-0.5em}

\bibitem{E31PornTraffic}
\url{http://www.straightdope.com/columns/051007.html}
\vspace*{-0.5em}

`


text:
Openholo  beta 2.0 Open Source Digital Holographic Library
Convert-HPO

## Functions

bool ophSig::sigConvertHPO ()
Function for convert complex hologram to horizontal parallax only hologram . More...

## Detailed Description

This module is related method which convert to horizontal parallax only hologram.

# Introduction

• The hologram contains all the information of a 3D object and require a large amount of transmission for use in a holographic display. However, because the capacity of the information transmission channel is limited, a great amount of research has been spent on holographic information reduction so as to facilitate, for example, TV transmission of holograms. A horizontal-parallax-only (HPO) hologram has been proposed as an excellent way to reduce the required amount of data for 3D display [1,2].
• Recently, HPO optical scanning holography(OSH) has been suggested as an electro-optical technique that actually records the holographic information of a real object without vertical parallax [3]. However, the proposed HPO OSH will introduce aberration upon optical reconstruction along the vertical direction if the vertical extent of the asymmetrical Fresnel zone plate (FZP), which has been proposed to generate the HPO data from a real object, is not small enough [3,4]. To eliminate aberration caused by the asymmetrical FZP, an algorithm that converts a recorded full-parallax (FP) hologram to an HPO hologram was subsequently proposed [4]. The converted HPO hologram was optically reconstruct using a conventional amplitude-only spatial light modulator (SLM) [5].

# Algorithm

• This method that converts a full-parallax hologram to an HPO hologram by using Gaussian low-pass filtering and fringe-matched filtering. Although a full-parallax hologram of a 3D object can be considered as a collec tion of 2D Fresnel zone plates (FZPs), an HPO hologram is a collection of 1D FZPs [3]. Figures 1(a) and 1(b) show a 2D FZP and an asymmetrical FZP, respectively. The asymmetrical FZP shown in Fig. 1(b) illustrates an approx imation to a line or 1D FZP by masking a slit along the x direction. Note that the asymmetrical FZP still has curvature within its vertical extent if the slit size is not small enough, and hence it will generate aberrat ion upon reconstruction of the hologram.
Figure 1. (a) Full-parallax FZP, (b) asymmetrical FZP.
• Gaussian low-pass filtering along the vertical direction removes the high-frequency components of the object along the vertical direction. This makes it possible to reduce the amount of data by sacrificing the vertical parallax without losing the horizontal parallax. The filtered output becomes a hologram in which the object is encoded by an asymmetrical FZP.
• Fringe-matched filter compensates the curvature of the Gaussian low-pass filtered hologram along the vertical direction and gives an exact HPO hologram as an output [1,2]. This makes it possible to removes the curvature along the vertical direction of the asymmetrical FZP.
• First, the full parallax complex hologram of the object obtained using the OSH setup is given by the following [6]:

$H_{full}(x,y)=\int_{z_0-\Delta z}^{z_0+\Delta z}I_0(x,y,z) \otimes \frac{j}{\lambda z} \times \exp \left \{ \left(\frac{\pi}{NA^2z^2}+j \frac{\pi}{\lambda z}\right)\left(x^2+y^2\right) \right \}dz \qquad \left(1\right)$

• Where $$NA$$ represents the numerical aperture defined as the sine of the half-cone angle subtended by the TD-FZP, $$\lambda$$ is the wavelength of the laser, $$z_0$$ is the depth location of the object, $$2\Delta z$$ is the depth range of the object, and the symbol $$\otimes$$ denotes 2D convolution. The spectrum of the hologram is given by

$H_{full}(k_x,k_y)=F\left\{H_{full}(x,y)\right\} =\int_{z_0-\Delta z}^{z_0+\Delta z}I_0(k_x,k_y,z) \times \exp \left \{ \left[-\frac{1}{4\pi}\left(\frac{\lambda}{NA}\right)+j \frac{\lambda z}{\lambda \pi}\right] \left(k_x^2+k_y^2\right) \right \}dz \qquad \left(2\right)$

• Where $$F\left\{.\right\}$$. represents Fourier transformation with $$\left(k_x,k_y\right)$$ denoting spatial frequencies.
• Next apply a Gaussian low-pass filter along the vertical direction, $$G_{low-pass}\left(k_x,k_y\right)=\exp\left[\frac{-1}{4\pi} \left(\frac{\lambda}{NA_g} \right)^2k_y^2 \right]$$, to the full-parallax hologram’s spectrum given by Eq. (2), where $$NA_g$$ is a parameter that determines the cut off frequency of the Gaussian low-pass filter. The filtered spectrum is then given by

$H_{asym\ FZP}\left(k_x,k_y\right) =H_{full}\left(x,y\right)G_{low-pass}\left(k_x,k_y\right) =\int_{z_0-\Delta z}^{z_0+\Delta z}{I_0(k_x,k_y,z) \times \exp\left\{\left[-\frac{1}{4\pi}\left(\frac{\lambda}{NA}\right)^2+j\frac{\lambda z}{4\pi}\right]k_x^2+ \left[-\frac{1}{4\pi}\left(\frac{\lambda}{{NA}_{lp}}\right)^2+j\frac{\lambda z}{4\pi}\right]k_y^2\right\}}dz \qquad \left(3\right)$

• Where $${\rm NA}_{lp}={\rm NA}_gNA/\sqrt{{\rm NA}^2+{NA}_g^2}$$ is the NA of the FZP along the vertical direction. Note that the Gaussian low-pass filtered hologram is a hologram in which the object’s cross-sectional images are encoded with the asymmetrical FZP. As discussed earlier, the asymmetric FZP has curvature along the vertical direction. To remove the curvature, use a fringe-matched filter, $$F_{fm}\left(k_x,k_y\right)=exp\left[-j\lambda z_0/4\pi k_y^2\right]$$, that compensates the curvature along the vertical direction, where $$z_0$$ is the depth location of the object. Hence the fringe-adjusted filtered output becomes

$H_{HPO}\left(k_x,k_y\right) =H_{asym\ FZP}\left(k_x,k_y\right)F_{fm}\left(k_x,k_y\right) =\int_{z_0-\Delta z}^{z_0+\Delta z}{I_0(k_x,k_y,z)\times \exp\left\{\left[-\frac{1}{4\pi} \left(\frac{\lambda}{NA}\right)^2+j\frac{\lambda z}{4\pi}\right]k_x^2+{\left[-\frac{1}{4\pi} \left(\frac{\lambda}{{NA}_{lp}}\right)^2+j\frac{\lambda\left(z-z_0\right)}{4\pi}\right]k}_y^2\right\}}dz \qquad \left(4\right)$

• The HPO hologram in space domain is given by $$H_{HPO}\left(x,y\right)=F^{-1}\left\{H_{HPO}\left(k_x,k_y\right)\right\}$$, where $$F^{-1}\left\{.\right\}$$. Represents the inverse Fourier transformation. Now, in the case that the depth range of the object $$\left(2\Delta z\right)$$ is smaller than the in-focus range of the line FZP along the vertical direction $$\left(2\Delta z_{ver_dir}=2\lambda/\left({NA}_{lp}^2\right)\right)$$, i.e., $$\Delta z\le\Delta z_{ver_dir}$$, which is usually true when we synthesize an HPO hologram for 3D display, $$z\approx z_0$$ within the range of the object depth along the y direction, and hence the last term of the exponential function become zero, i.e., $$\lambda\left(z-z_0\right)/4\pi\approx 0$$. Equation (4) then becomes

$H_{HPO}\left(k_x,k_y\right) =\int_{z_0-\Delta z}^{z_0+\Delta z}{I_0(k_x,k_y,z) \times \exp\left\{\left[-\frac{1}{4\pi}\left(\frac{\lambda}{NA}\right)^2+j\frac{\lambda z}{4\pi}\right]k_x^2 +{\left[-\frac{1}{4\pi}\left(\frac{\lambda}{NA_{lp}}\right)^2\right]k}_y^2\right\}}dz \qquad \left(5 \right )$

• and its spatial domain expression is

$H_{HPO}\left(x,y\right)=F^{-1}\left\{H_{HPO}\left(k_x,k_y\right)\right\} =\int_{z_0-\Delta z}^{z_0+\Delta z}{I_0(x,y,z)\otimes\frac{j}{\lambda z} \times \exp\left\{-\left[-\left(\frac{\pi}{NA^2z^2}\right)+j\frac{\pi}{\lambda z}\right]x^2 +\frac{\lambda}{NA_{lp}^2z^2}y^2\right\}}dz \qquad (6)$

Figure 2. Flowchart

# Reference

• [1] P. St. Hilaire, S. A. Benton, and M. Lucente, “Synthetic aperture holography: a novel approach to three-dimensional displays,” J. Opt. Soc. Am. A 9, 11, 1969-1977 (1992).
• [2] H. Yoshikawa and H. Taniguchi, “Computer Generated Rainbow Hologram,” Opt. Rev. 6, 118 (1999).
• [3] T.-C. Poon, T. Akin, G. Indebetouw, and T. Kim, “Horizontal parallax-only electronic holography,” Opt. Express 13, 2427–2432 (2005).
• [4] T. Kim, Y. S. Kim, W. S. Kim, and T.-C. Poon, “Algorithm for converting full-parallax holograms to horizontal parallax-only holograms,” Opt. Lett. 34, 1231–1233 (2009).
• [5] Y. S. Kim, T. Kim, T.-C. Poon, and J. T. Kim, “Three-dimensional display of a horizontal-parallax-only hologram,” Applied Optics Vol. 50, Issue 7, pp. B81-B87 (2011)
• [6] T.-C. Poon, T. Kim, G. Indebetouw, M. H. Wu, K. Shinoda, and Y. Suzuki, “Twin-image elimination experiments for three-dimensional images in optical scanning holography,” Opt. Lett. 25, 215 (2000).

## ◆ sigConvertHPO()

 bool ophSig::sigConvertHPO ( )

Function for convert complex hologram to horizontal parallax only hologram .

Returns
if works well return 0 or error occurs return -1

Definition at line 690 of file ophSig.cpp.

690  {
691  OphComplexField F1, G1, OUT_H;
692  int nx = context_.pixel_number[_X];
693  int ny = context_.pixel_number[_Y];
694  double y;
695  F1.resize(ny, nx);
696  G1.resize(ny, nx);
697  OUT_H.resize(ny, nx);
698  float NA = _width / (2 * _z);
699  float NA_g = NA*_redRate;
700  int i, j;
701  int xshift = nx / 2;
702  int yshift = ny / 2;
703  double temp = 0.;
704  double temp2 = 0.;
705  double sigmaf = (_z*(*context_.wave_length)) / (4 * M_PI);
706
707  for (i = 0; i < ny; i++)
708  {
709  int ii = (i + yshift) % ny;
710  y = (2 * M_PI*(i) / _height - M_PI*(nx - 1) / _height);
711  temp = sigmaf*(y*y);
712  temp2 = ((-M_PI*(((*context_.wave_length) / (2 * M_PI*NA_g))*((*context_.wave_length) / (2 * M_PI*NA_g))))*((y*y)));
713  for (j = 0; j < nx; j++)
714  {
715  int jj = (j + xshift) % nx;
716  F1(ii, jj)._Val[_RE] = cos(temp);
717  F1(ii, jj)._Val[_IM] = sin(temp);
718  G1(ii, jj)._Val[_RE] = std::exp(temp2);
719  G1(ii, jj)._Val[_IM] = 0;
720  }
721  }
722  fft2(ComplexH[0], OUT_H, OPH_FORWARD);
723  G1.mulElem(F1.mulElem(OUT_H));
724  fft2(G1, ComplexH[0], OPH_BACKWARD);
725  return true;
726 }
void fft2(matrix< Complex< T >> &src, matrix< Complex< T >> &dst, int sign=OPH_FORWARD, uint flag=OPH_ESTIMATE)
Function for Fast Fourier transform 2D.
Definition: ophSig.cpp:226


text:
# QUESTIONFind the that meets the conclusion oftne Mean Value Theorem for Derivatives on the interval from [0,4]: Use two decimal

###### Question:

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E2-11 Recording Journal Entries and Preparing a Classified Balance Sheet (LO 2-1, LO 2-2, LO 2-5) Assume Down, Inc., was organized on May 1 to compete with Despair, Inc.-a company that sells de-motivational posters and office products. Down, Inc., encountered the following events during its first mo...
##### A chair of weight 145 N lies atop a horizontal floor; the floor is not frictionless....
A chair of weight 145 N lies atop a horizontal floor; the floor is not frictionless. You push on the chair with a force of F = 41.0 N directed at an angle of 39.0 ∘ below the horizontal and the chair slides along the floor. Using Newton's laws, calculate n, the magnitude of the normal forc...
##### Uciune rako for
Uciune rako for...
##### For Iho standard normal distributon shown on Ihe righl; find Iho probabllity ol z occurring In indicated region Clckkeroulo view page Lotlhe slandard noral lable Clckhae lipage ? ollle_slandar noILlabaTno prababuly (Round to Iour decanal placos a5 noodod )
For Iho standard normal distributon shown on Ihe righl; find Iho probabllity ol z occurring In indicated region Clckkeroulo view page Lotlhe slandard noral lable Clckhae lipage ? ollle_slandar noILlaba Tno prababuly (Round to Iour decanal placos a5 noodod )...
##### 4. Suppose you wish to encrypt the message, M 42 using RSA encryption. Given a public...
4. Suppose you wish to encrypt the message, M 42 using RSA encryption. Given a public key where p- 23 and q-11 and the relative prime e- 7. Find n, and show all necessary steps to encrypt your message (42). (Hint: check p.411 of the text for information on public key RSA) (5 points)...
##### A buffer solution was prepared by adding 8.01 g of NHACl to 75.00 mL of 1.92 M NHy in a 500 mL volumetric flask and diluting the mark with water. Calculate the pH of the resulting buffer solution:Kb (NH,)-1.83 * 10 5
A buffer solution was prepared by adding 8.01 g of NHACl to 75.00 mL of 1.92 M NHy in a 500 mL volumetric flask and diluting the mark with water. Calculate the pH of the resulting buffer solution: Kb (NH,)-1.83 * 10 5...
##### The Valueof X in a Particular Situation depends on: a) te left hand tail area a b) e nunber Of degrees Of freedom c) the right hand ta] area thl Ieft hand tai [ area and +c number Ot degrees 0 f Frecjum tk numbcr 0E dejrecs o â‚¬ Areld on and th rght taod +4 | Gre u
The Valueof X in a Particular Situation depends on: a) te left hand tail area a b) e nunber Of degrees Of freedom c) the right hand ta] area thl Ieft hand tai [ area and +c number Ot degrees 0 f Frecjum tk numbcr 0E dejrecs o â‚¬ Areld on and th rght taod +4 | Gre u...
##### In 2010, large manuiacturing iirm in Turkey being charged with discrimination in its hiring practices. What hypothesis being tested if jury commits type error by finding the iirm guilty? What hypothesis being tested jury commits type ertor Dy finding- the firm guilty?Choose the correct answer belowThe firm guilly: The evidence inconclusiveThe firm innocentThe firm is not guilty-Choose the correct answer below:The firm is not guilty- The firm is innocentThe evidence inconclusiveThe firm guilly:
In 2010, large manuiacturing iirm in Turkey being charged with discrimination in its hiring practices. What hypothesis being tested if jury commits type error by finding the iirm guilty? What hypothesis being tested jury commits type ertor Dy finding- the firm guilty? Choose the correct answer below...
##### Tha pulsa ratat 0l 147 rndomly soloctad ndult malo: vary from n bx 0t 41 bpm lo  tgh of 121 bpm Find the mnimum tamplo Biz0 requited {0 elnnla Ine Moan Duaco [ adult malosAssumo IdE Wunt 9573 conlidence Inat tha sample Inoan Minin 3 bom ol tha popultton mean Complolu purts (n) Inrough (c)bolotFind tha sarolo 4U Uslng Ine tanqu rula ot Ihurnb osurata(Round up Io Ina noaroet whola numbot 0 needlod )
Tha pulsa ratat 0l 147 rndomly soloctad ndult malo: vary from n bx 0t 41 bpm lo  tgh of 121 bpm Find the mnimum tamplo Biz0 requited {0 elnnla Ine Moan Duaco [ adult malosAssumo IdE Wunt 9573 conlidence Inat tha sample Inoan Minin 3 bom ol tha popultton mean Complolu purts (n) Inrough (c)bolot Fin...
##### In performing the following dihybrid testcross, I obtain the following F2 phenotypes. What is the distance...
In performing the following dihybrid testcross, I obtain the following F2 phenotypes. What is the distance between the loci that control flower color and pollen length? P: Long, red x white, short, F1: Long, red x white, short, F2: 450 Red, long, 470 white, short, 42 Red, short, 38 white, long a. 0...
##### 2 1 6 Obsetve the organism Dashboard 1 V 8 E 1 Help 1 oftheer suousand Scurch 1 and questions 1 3 Moizo Your U pinous bech oi vour posmteform: MiEoeggs 1 1 gveotebrates : Cunnolexdanc inoracc 1 81 does nol navc3pronuced auio /4
2 1 6 Obsetve the organism Dashboard 1 V 8 E 1 Help 1 oftheer suousand Scurch 1 and questions 1 3 Moizo Your U pinous bech oi vour posmteform: MiEo eggs 1 1 gveotebrates : Cunnolexdanc inoracc 1 8 1 does nol navc 3 pronuced auio /4...
##### 1-Which of the following are ways GDP can overstate the standard of living? Select the correct...
1-Which of the following are ways GDP can overstate the standard of living? Select the correct answer below: Factors not included in the GDP, such as environmental cleanliness are getting better. The GDP does not capture leisure and new technology, which have improved for Americans. GDP ignores fact...
##### 5) A power cycle operates between hot and cold reservoirs of 5000C and 200C respectively: 1600kW are transferred from the hot reservoir into the power cycle and the cycle's inventor claims that it produces 1000 kW:Evaluate this claim with both an energy and an entropy balance. Is it possible or impossible? Cite two mathematical expressions to support your conclusion_Show all of your work; including all symbolic and numeric equations with units , and cite all Table References for full credit
5) A power cycle operates between hot and cold reservoirs of 5000C and 200C respectively: 1600kW are transferred from the hot reservoir into the power cycle and the cycle's inventor claims that it produces 1000 kW: Evaluate this claim with both an energy and an entropy balance. Is it possible o...
##### Problem 2: Suppose in the example of the bird population; given earlier; (k+[ Zax +1 gjk jk+l 2akandd0100jo 40(1) Write the above system as a matrix equation Xa+l AXk . (2) Find the eigenvalues of A rounded to three decimal places and an eigenvector for each eigenvalue_ (3) What is the dominant eigenvalue? Do the populations become extinct; stabilize or diverge? (4) Give an approximation for &x and jk using the dominant eigenvalue and use this approximation tO estimate the adult and juvenile
Problem 2: Suppose in the example of the bird population; given earlier; (k+[ Zax +1 gjk jk+l 2ak and d0 100 jo 40 (1) Write the above system as a matrix equation Xa+l AXk . (2) Find the eigenvalues of A rounded to three decimal places and an eigenvector for each eigenvalue_ (3) What is the dominant...
##### 4{12 polntsperiume mhture of volut i conijounds thosc coTpound' Wnlt milltnt nMa avcrant dirlualon Iemnci Wtmld comd ctcle Ayutadu (nt Oilaro Allelrcinul Ral How: Inutut wnul Ike Ior!ni Gemoic avetnge dua nce dinul nverona ciatu nc4 Unknorn ubetarce ddluaed uunne dlatonce Uaccnt Kamezene enle eeeananDiteCDAnc "NiLEntMannocompletelt
4{12 polnts periume mhture of volut i conijounds thosc coTpound' Wnlt milltnt nMa avcrant dirlualon Iemnci Wtmld comd ctcle Ayutadu (nt Oilaro Allelrcinul Ral How: Inutut wnul Ike Ior!ni Gemoic avetnge dua nce dinul nverona ciatu nc4 Unknorn ubetarce ddluaed uunne dlatonce Uaccnt Kamezene enle...
##### If $A$ and $B$ are two sets then $B-(B-A)=ldots ldots ldots$(a) $(mathrm{A}-mathrm{B})-mathrm{B}$(b) $A-(A-B)$(c) $mathrm{A}$(d) $mathrm{B}$
If $A$ and $B$ are two sets then $B-(B-A)=ldots ldots ldots$ (a) $(mathrm{A}-mathrm{B})-mathrm{B}$ (b) $A-(A-B)$ (c) $mathrm{A}$ (d) $mathrm{B}$...
##### Yahoo Indonesia M Gmail YouTube Maps HB Apple Recalls Mac... ework A Mauro Products distributes a...
Yahoo Indonesia M Gmail YouTube Maps HB Apple Recalls Mac... ework A Mauro Products distributes a single product, a woven basket whose selling price is $14 per unit and whose variable expense is$10 per unit. The company's monthly fixed expense is \$7,600. Required: 1. Calculate the company's...
##### JEEA Ur 1 ji L Homework1O MAA 1 1 EU16U-Timz 0I 1 1 | 5 M Problem 21
JEEA Ur 1 ji L Homework1O MAA 1 1 EU16U-Timz 0I 1 1 | 5 M Problem 21...
##### Not yet answered Marked out of 1.00Question 32Infectious agents quarantined in a granuloma can escape into the surrounding tissue and replicate when levels of which of the following cytokine diminish? Select one:a. IL-4b. Thymic stromal lymphopoietin (TSLP)C_ IFN-gammad. TGF-betae. IL-10
Not yet answered Marked out of 1.00 Question 32 Infectious agents quarantined in a granuloma can escape into the surrounding tissue and replicate when levels of which of the following cytokine diminish? Select one: a. IL-4 b. Thymic stromal lymphopoietin (TSLP) C_ IFN-gamma d. TGF-beta e. IL-10...
##### An object with a mass of 1 kg, temperature of 125 ^oC, and a specific heat of 32 (KJ)/(kg*K) is dropped into a container with 15 L  of water at 0^oC . Does the water evaporate? If not, by how much does the water's temperature change?
An object with a mass of 1 kg, temperature of 125 ^oC, and a specific heat of 32 (KJ)/(kg*K) is dropped into a container with 15 L  of water at 0^oC . Does the water evaporate? If not, by how much does the water's temperature change?...
##### What are members opinions of the annual membership fee charged by Extreme Exposure? will members consider...
what are members opinions of the annual membership fee charged by Extreme Exposure? will members consider leaving Extreme Exposure to join a new rock-climbing center with higher climbs and a lower annual membership fee? will members consider leaving Extreme Exposure to join a new rock-climbing cente...
##### Ethers can be formed under acidic or basic conditions. What are the limitation of forming an...
Ethers can be formed under acidic or basic conditions. What are the limitation of forming an ether from an alcohol under acidic conditions? I. Asymmetrical ethers cannot be formed exclusively under acidic conditions II. Rearrangement in the carbon skeletal backbone is possible under acidic condition...
##### A cylinder measuring 3.2 cm wide and 3.8 cm high is filled with gas The piston is pushed down with steady force measured to be 16.N_pistoncylinder gasCalculate the pressure of the gas inside the cylinder. Write your answer in units of kilopascals_ Round your answer to 2 significant digits_KPa
A cylinder measuring 3.2 cm wide and 3.8 cm high is filled with gas The piston is pushed down with steady force measured to be 16.N_ piston cylinder gas Calculate the pressure of the gas inside the cylinder. Write your answer in units of kilopascals_ Round your answer to 2 significant digits_ KPa...
##### Suppose that the random variables Xp and Xz are inde- pendent; and that each has the normal distribution with mean / and variance 0 Prove that the random variables Xi + Xzand X1 Xz are independent:
Suppose that the random variables Xp and Xz are inde- pendent; and that each has the normal distribution with mean / and variance 0 Prove that the random variables Xi + Xzand X1 Xz are independent:...
##### Evaluate the integraltnh1 dx 2 sech? 1 +C In (cot3) +C 2 In |anh- 1 +C 2 In Icosh { +C
Evaluate the integral tnh 1 dx 2 sech? 1 +C In (cot3) +C 2 In |anh- 1 +C 2 In Icosh { +C...
##### Which group of elements includes the most reactive of all the metallic elements? alkali metals alkaline...
Which group of elements includes the most reactive of all the metallic elements? alkali metals alkaline earth metals coinage metals (Group 1B) transition metals Group 2B metals Determine all of the covalent hydrides from the compounds listed below. CaH2 H2S SiH4 I only II only I and II I a...
##### The following are taken from the Chart of Accounts for the Veteran Community Hospital, a Voluntary...
The following are taken from the Chart of Accounts for the Veteran Community Hospital, a Voluntary Health & Welfare Organization (VHWO).  Prepare a Statement of Activities showing where each item would be placed on the financial statement. Program Services – Counseling Net Assets...
##### 9. Assume that at the end of a war the ratio of government debt to GDP...
9. Assume that at the end of a war the ratio of government debt to GDP is 100%. If GDP grows at 5% and the government's budget is balanced every year, approximately how long will it take for the debt to GDP ratio to fall to 50%? years...
##### Suppose that U is a vector with five entries and Ilvllo =1. Suppose that W is a vector with five entries and Ilwll2 =1. How large could Ilvllz be? Give an example. How small could Ilvllz be? Give an example. How large could Ilwllo be? Give an example. How small could Ilwllo be? Give an example.
Suppose that U is a vector with five entries and Ilvllo =1. Suppose that W is a vector with five entries and Ilwll2 =1. How large could Ilvllz be? Give an example. How small could Ilvllz be? Give an example. How large could Ilwllo be? Give an example. How small could Ilwllo be? Give an example....
##### Please answer 3! You will be using 25.00 mL of 3.00% by mass solution ({mass H_2O_2/...
Please answer 3! You will be using 25.00 mL of 3.00% by mass solution ({mass H_2O_2/ mass solution}*100) of hydrogen peroxide. Assume the density of this solution is 1.000 g / mL. If all hydrogen peroxide decomposes to water and oxygen according to the reaction 2H_2O_2 (aq) 2H_2O (I) + O_2(g) What...
##### Aw the correct product for the following Diels Alder reaction:
aw the correct product for the following Diels Alder reaction:...

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