52849083
Data extraction from Web data sources
An explanation is given of the basic data structures used in a new page analysis technique to create wrappers (data extractors) for the result pages produced by Web sites in response to user qeries via Web page forms. The key structure called a tpGrid is a representation of the web page, which is easier to analyse than the raw HTML code. The analysis looks for repetition patterns of sets of tagSets, which are defined in the paper.
14933774
Using a Network of Workstations to Enhance Database Query Processing Performance
Query processing in database systems may be improved by applying parallel processing techniques. One reason for improving query response time is to support the increased number queries when databases are made accessible from the Internet.
6479052
Data Analysis for Query Processing
Data analysis is needed in connection with query processing, to produce data summary information in the form of rules or assertions that allow semantic query optimisation or direct query answering without consulting the data itself. The goal of an intelligent analyser in this context is to produce robust rules, stable in the presence of data changes, which allow easy rule maintenance as data changes, and provide rapid query reformulation, refutation or answering. It must also limit the rule set to rules useful for query processing.
9837737
Attribute-Pair Range Rules
This paper examines the properties of metadata in the form of IF THEN rules which contain two predicates on attributes of a relational database table. For example: a(15. 30) ⟹ d(243. 271), which means “if the value of attribute ‘a’ in a tuple is in the range 15 to 30 then the value of attribute ‘d’ will be in the range 243 to 271.” Metadata of this kind is useful in Semantic Query Optimisation and Remote Cache Management. The two predicates (antecedent and consequent) in each rule are Selection Conditions or constraints of the type found in database queries. Each condition therefore denotes a subset of a database table. Rules can be cascaded, using subrange containment as the link between successive rules. The set of rules can therefore be regarded as a set of edges in a Condition Dependency Graph, and using the rule-set is path discovery in the graph. The purpose of the current paper is to introduce some of the properties of attribute-pair range rules.
10379830
Extended Query Answering Using Integrity Rules
The conventional use of databases is commonly restricted to the retrieval of factual data in the form of tuples or records. However most databases also contain metadata in the form of integrity rules which can provide a rich source of additional information not normally available to the user. Integrity rules define what data values and relationships may exist within the database and so their interrogation can provide answers as to whether a certain database state is possible. Our paper describes how this may be achieved and specifies a formal approach to implementing such an enquiry system.
34571067
Data Extraction from Web Database Query Result Pages via Tagsets and Integer Sequences
The World Wide Web is a collection of databases as well as web sites. Databases associated with web sites provide public access via query forms on web pages. They constitute an enormous repository of searchable data on an extremely diverse collection of subjects, ranging from multimedia collections through archives of subject-specific data to current information such as currency conversion or interest rates and news or weather reports. Many interesting and valuable Database Applications could be developed if these databases were easily and reliably accessible to programs. The difficulty in extracting data is the number of different web page formats and the tendency to change format suddenly. A rapid page analysis and wrapper creation system is needed to generate and maintain a data extraction facility for any required web sites. This important goal has been the subject of substantial recent research, modelling the web results page in various ways. The purpose of the current paper is to introduce a new method for rapid page analysis using the recurrence patterns of tagSet occurrence in the page.
2266734
Procedures for Integrating Knowledge in a Speech Understanding System
T h i s paper d e s c r i b e s t h e p r o c e d u r e s f o r i n t e g r a t i n g knowledge f rom d i f f e r e n t s o u r c e s i n t h e SRI speech u n d e r s t a n d i n g s y s t e m . A language d e f i n i t i o n sys tem c o o r d i n a t e s — a t t h e ph rase l e v e l — i n f o r m a t i o n f rom s y n t a x , s e m a n t i c s and d i s c o u r s e i n t h e cou rse o f t h e i n t e r p r e t a t i o n o f a n u t t e r a n c e . The sys tem e x e c u t i v e uses t h e s e c o n t e x t u a l c o n s t r a i n t s i n a s s i g n i n g p r i o r i t i e s t o a l t e r n a t i v e i n t e r p r e t a t i o n s , c o m b i n i n g t o p d o w n , b o t t o m u p , and b i d i r e c t i o n a l s t r a t e g i e s a s r e q u i r e d E x p e r i m e n t a l r e s u l t s t h a t d e m o n s t r a t e t h e e f f e c t i v e n e s s o f c o n t e x t c h e c k i n g a r e d i s c u s s e d .
14389185
A Machine-Oriented Logic Based on the Resolution Principle
:tb.~tract. Theorem-proving on the computer, using procedures based on the fund~mental theorem of Herbrand concerning the first-order predicate etdeulus, is examined with ~ view towards improving the efticieney and widening the range of practical applicability of these procedures. A elose analysis of the process of substitution (of terms for variables), and the process of t ruth-funct ional analysis of the results of such substitutions, reveals that both processes can be combined into a single new process (called resolution), i terating which is vastty more ef[ieient than the older cyclic procedures consisting of substitution stages alternating with truth-functional analysis stages. The theory of the resolution process is presented in the form of a system of first<~rder logic with .just one inference principle (the resolution principle). The completeness of the system is proved; the simplest proof-procedure based oil the system is then the direct implementation of the proof of completeness. Howew~r, this procedure is quite inefficient, ~nd the paper concludes with a discussion of several principles (called search principles) which are applicable to the design of efficient proof-procedures employing resolution as the basle logical process.
17448440
Effective implementation of cycle time reduction strategies for semiconductor back-end manufacturing
Using discrete event simulation models, a study was conducted to evaluate the current production practices of a high volume semiconductor back-end operation. The overall goal was to find potential areas for productivity improvement that would collectively yield a 60% reduction in manufacturing cycle time. The paper presents the simulation methodology and findings pertaining to analysis of the Assembly, Burn-In, and Test operations. Many of the recommendations identified can be implemented at no additional cost to the factory. The most significant opportunities for improvement are in the Test area, the system constraint. Additionally, the model is extremely sensitive to changes in operator staffing levels, an accurate reflection of many back-end operations. The model shows that the cumulative impact of these recommendations is a 41% reduction in average cycle time, a significant contribution to the overall goal.
15957762
Sensor networks and grid middleware for laboratory monitoring
By combining automatic environment sensing and experimental data collection with broker based messaging middleware, a system has been produced far the real-time monitoring of experiments whilst away from the lab. Changes in the laboratory environment are encapsulated as simple messages, which are published using an MQTT compliant broker. Clients subscribe to the MQTT stream, and perform a data transform on the messages; this may be to produce a user display or to change the format of the message for republishing. For example, an MQTT client written for the Java MIDP platform can be run on a smart-phone with a GPRS Internet connection, freeing us from the constraints of the network. We present an overview of the technologies used, and how these are helping chemists make the best use of their time
27367510
Genetic search for Golomb arrays
Genetic search with a decision level chromosome is used to search efficiently for Golomb (1982) arrays. A Golomb array A is a binary array with three values for its discrete autocorrelation function; M, the number of ones in A for no offset, 1 when there is partial overlap, and 0 otherwise. In one dimension, A is known as a Golomb ruler. The method yields improvement because the genetic search considers only feasible solutions in the most likely portion of the search space. Each chromosome bit represents a decision to place a one in an iterative construction. The representation includes all possible arrays. Since the chromosome bits represent binary decisions in the search space, genetic operations (such as crossover and mutation) always result in feasible descendent chromosomes. Experimental results include comparison to previously known search methods and several new arrays. These results indicate that the proposed search is significantly more efficient than prior methods.