9935746
The JSIM web-based simulation environment
Abstract In its ideal form, web-based simulation should allow simulation models as well as simulation results to be as readily distributable and composable as today’s web documents. The rapid advances in web technology, most notably Java, are helping to make this a possibility. Support for executable web content, universal portability, component technology, and standard high-level packages for accessing databases and producing graphical user interfaces are important enablers of web-based simulation. Component-based software can be used to develop highly modular simulation environments supporting high reusability of software components. Because of the potentially large scope of web-based simulation, greater demands are placed on simulation environments. They should support rapid visual model development, access to local and remote databases, techniques for executing models or federations of models in a variety of ways, and embedding of simulation within larger systems. The use of component technology in the JSIM web-based simulation environment allows simulation models to be treated as components that can be dynamically assembled to build model federations. It also allows simulation inputs and outputs to be dynamically linked to database systems, making storage of simulation results easy and flexible.
2346213
Healthcare Enterprise Process Development and Integration
Healthcare enterprises involve complex processes that span diverse groups and organisations. These processes involve clinical and administrative tasks, large volumes of data, and large numbers of patients and personnel. The tasks can be performed either by humans or by automated systems. In the latter case, the tasks are supported by a variety of software applications and information systems which are very often heterogeneous, autonomous, and distributed. The development of systems to manage and automate these processes has increasingly played an important role in improving the efficiency of healthcare enterprises. In this paper we look at four healthcare and medical applications that involve investigative, clinical, and administrative functions. Based on these applications, we derive the requirements for developing enterprise applications that involve the coordination of a variety of tasks performed by humans, information systems, and legacy applications.
15234568
Demonstrating Dynamic Configuration and Execution of Web Processes
Web processes are next generation workflows on the web, created using Web services. In this paper we demonstrate the METEOR-S Configuration and Execution Environment (MCEE) system. It will illustrate the capabilities of the system to a) Discover partners b) Optimize partner selection using constraint analysis, c) Perform interaction protocol and data mediation. A graphical execution monitor to monitor the various phases of execution will be used to demonstrate various aspects of the system.
30146652
Workflow Quality of Service
Workflow management systems (WfMSs) have been used to support various types of business processes for more than a decade now. In ecommerce processes, suppliers and customers define a binding agreement or contract between the two parties, specifying quality of service (QoS) items such as products or services to be delivered, deadlines, quality of products, and cost of service. Management of such QoS directly impacts success of organizations participating in e-commerce. Organizations operating in modern markets require an excellent degree of quality of service management. Products and services must be available to customers with well-defined specifications. A good management of quality leads to the creation of quality products and services, which in turn fulfills customer expectations and achieves customer satisfaction. Therefore, when services or products are created or managed using workflow processes, the underlying WfMS must accept the specification, be able to predict, monitor, and control the QoS rendered to customers. To achieve these objectives the first step is to develop an adequate QoS model for workflow processes and develop methods to compute QoS.
9294328
Performance Modeling of Database Recovery Protocols
The performance modeling described in this paper compares several protocols which ensure that a database can be recovered to a consistent state after a transaction failure or system crash. The contributions of the paper include a collection of simple analytic models, based on Markov processes, for these protocols and some surprising results on the relative performance of the protocols. We consider only two-stage transactions (all reads before writes) and ignore effects of serializing transactions. The most interesting performance result presented is that, for systems obeying the assumptions of this paper, the "pessimistic" policy of holding write locks to commit point is considerably less efficient than the "optimistic" policy which allows reading of uncommitted data, but risks cascading aborts. A multiversion policy introduced in [2] was also studied and found always to be nearly as good as the optimistic policy and sometimes much better.
3039342
Adding Semantics to Web Services Standards
With the increasing growth in popularity of Web services, discovery of relevant Web services becomes a significant challenge. One approach is to develop semantic Web services where by the Web services are annotated based on shared ontologies, and use these annotations for semantics-based discovery of relevant Web services. We discuss one such approach that involves adding semantics to WSDL using DAML+OIL ontologies. Our approach also uses UDDI to store these semantic annotations and search for Web services based on them. We compare our approach with another initiative to add semantics to support Web service discovery, and show how our approach may fit current standards-based industry approach better.
8365397
Input modeling when simple models fail
A simulation model is composed of inputs and logic; the inputs represent the uncertainty or randomness in the system, while the logic determines how the system reacts to the uncertain elements. Simple input models, consisting of independent and identically distributed sequences of random variates from standard probability distributions, are included in every commercial simulation language. Software to fit these distributions to data is also available. In this tutorial we describe input models that are useful when simple models are not.
1650301
The spreadsheet interface: A basis for end user programming
52857539
Computer graphics
17043790
Collaborative, programmable intelligent agents
A growing number of computer systems,in the hope that such simulations w as we had thought. More recently, however, resources for such work can be obtained from untapped source: the generation of extremely large numbers of graduate students and their subsequent application to the creation of alternate “Simulating Complex Adaptive Systems -What can we really learn?” Dr. B. Rubble Bedrock Inst. Brub@bedrock.edu Friday, December 6, 1996 11:00 a.m. – 12:00 noon Singapore Rm. 1st Floor R&D Building #1 Place on electronic calender brub@bedrock.edu Friday,December 6, 1996 11:00 a.m... Mail to secretary for scheduling Done Figure 1. Sample invocation of Apple Data Detectors. The user has selected a portion of an email message describing an upcoming seminar. Two patterns are found: an email address (brub@bedrock.edu) and the announcement of the meeting (the sequence of date and time information starting Friday, Dec. 6, 1996). These patterns are presented in the pop-up menu; by pointing at the date information in the menu; a second pop-up menu offers a choice of actions: place an entry for the meeting on the user’s electronic calendar or mail the selection to the user’s secretary. The user can select one, thereby running a small application, or move the cursor off the menu, eliminating the pop-up menu and canceling any actions. agents also varies across different agent-based systems; some act only within one’s own machine, find others autonomously crawl the Web, searching for interesting content [4]. We tried to find a middle ground by using explicit representations of user-relevant information as a means of identifying actions users might wish to take but to leave the choice of these actions to users. Working with Information Inside User Documents Our first step was to find a user problem that needed solving in which intelligent agents would add value. In an investigation of how people file information on their computer desktops [1], we discovered that a common user complaint is that they cannot easily take action on the structured information found in everyday documents (structured information being data-recognizable by a grammar). Ordinary documents are full of such structured information: phone numbers, fax numbers, street addresses, email addresses, email signatures, abstracts, tables of contents, lists of references, tables, figures, captions, meeting announcements, Web addresses, and more. In addition, there are countless domain-specific structures, such as ISBN numbers, stock symbols, chemical structures, and mathematical equations. These structures are not only relevant to users, but because of their structure, are also recognizable by parsing technologies. Once identified, the structure’s type can be used to identify appropriate actions that might be carried out, like placing a meeting on a calendar, adding an address to an address book, dialing a phone number, opening a URL, finding the current price of a stock, filing an ISBN number, and compiling a list of abstracts. Apple Data Detectors supports a wide range of uses. Think of all the structured information in the documents you work with; in addition to those mentioned already, add bibliography items, forms (such as travel expense reports and non-disclosure agreements), executive summaries, and most important, such domain-specific kinds of data as legal boilerplate, customer orders, and library search requests. Specific detectors can be created for each of these types of information. User interface. To use Apple Data Detectors, users select a region of a document with some information of interest. Pressing a modifier key and the mouse button instructs the system to analyze the data within the selected region and to find all structures for which it has grammars. It then offers appropriate actions for each structure (see Figure 1). For example, for users reading email who come across a seminar announcement they would like to put on a calendar, Apple Data Detectors parses the relevant information within the selected text, including the meeting’s place, time, and date and puts this data into the appropriate fields on the calendar. A user can select a whole document or part of a document without having to make a careful selection; the grammars find any embedded structures they know about within the selection and offer an appropriate set of actions from which to choose. The use of anthropomorphism in an agent interface [12] was incongruent with our goal of unobtrusiveness. We designed Apple Data Detectors to be invis98 March 1998/Vol. 41, No. 3 COMMUNICATIONS OF THE ACM User Application Presentation User Interface Apple Data Detectors Detectors Database Actions Folder HTTP = (Http Protocol, Host, Port?, Path?, {Http Location, Http Search} ? ) Http Protocol = {“http://”, “https://”} Port = (“:”, Port Number) Port Number = Digits Figure 2. The Apple Data Detectors architecture, which separates the application in which the information is found, the presentation of the analysis and possible actions, and the analysis of the information itself. This separation means that Apple Data Detectors can be invoked in any application and that the user interface can be implemented, refined, and evolved separately from the analysis module. Figure 3. A grammar to define a URL. The language implements a context-free grammar in which sequences of terms are matched against the input stream. References to other grammars are permitted, as are optional and repeated terms. Here, the HTTP grammar finds a match when it finds an HTTP protocol, a host, a port (optional), a path (optional), and either an HTTP location indicator or an HTTP search command and arguments.
14082423
Neutrality and the Evolvability of Boolean Function Landscape
This work is a study of neutrality in the context of Evolutionary Computation systems. In particular, we introduce the use of explicit neutrality with an integer string coding scheme to allow neutrality to be measured during evolution. We tested this method on a Boolean benchmark problem. The experimental results indicate that there is a positive relationship between neutrality and evolvability: neutrality improves evolvability. We also identify four characteristics of adaptive/neutral mutations that are associated with high evolvability. They may be the ingredients in designing effective Evolutionary Computation systems for the Boolean class problem.