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CC+Erratic Fudgets: a semantic theory for an embedded coordination language?Science of Computer ProgrammingThe powerful abstraction mechanisms of functional programming languages provide the means to develop domain-specific programming languages within the language itself. Typically, this is realised by designing a set of combinators (higher-order reusable programs) for an application area, and by constructing individual applications by combining and coordinating individual combinators. This paper is concerned with a successful example of such an embedded programming language, namely Fudgets, a library of combinators for building graphical user interfaces in the lazy functional language Haskell. The Fudget library has been used to build a number of substantial applications, including a web browser and a proof editor interface to a proof checker for constructive type theory. This paper develops a semantic theory for the non-deterministic stream processors that are at the heart of the Fudget concept. The interaction of two features of stream processors makes the development of such a semantic theory problematic:the sharing of computation provided by the lazy evaluation mechanism of the underlying host language, andthe addition of non-deterministic choice needed to handle the natural concurrency that reactive applications entail.We demonstrate that this combination of features in a higher-order functional language can be tamed to provide a tractable semantic theory and induction principles suitable for reasoning about contextual equivalence of Fudgets.MetaOCaml server pages: Web publishing as staged computation?Modern dynamic web services are really computer programs. Some parts of these programs run off-line, others run server-side on each request, and still others run within the browser. In other words, web publishing is staged computation, either for better performance, or because certain resources are available in one stage but not another. Unfortunately, the various web programming languages make it difficult to spread computation over more than one stage. This is a tremendous opportunity for multi-stage languages in general, and for MetaOCaml in particular.We present the design of MetaOCaml Server Pages. Unlike other languages in its genre, the embedded MetaOCaml code blocks may be annotated with staging information, so that the programmer may safely and precisely control which computation occurs in which stage. A prototype web server, written in OCaml, supports web sites with both static and dynamic content. We provide several sample programs and demonstrate the performance gains won using multi-stage programming.An embedded system for knowledge-based cost evaluation of molded parts?Knowledge-Based Systems In this paper, we present an embedded knowledge-base system and apply it to estimate the manufacturing cost of molded parts. This system is designed on a tiny single board computer, called the Gumstix?, which is an inexpensive and high-performance miniaturized platform. It consists of a knowledge-base, knowledge processing units and server service unit for user interactions, all of which are implemented on the Gumstix computer. A CAD server is provided for the interaction with commercial CAD software and all operations with users are performed via a web browser. This hardware and software structure features a realization of the Plug & Play concept and provides low-cost, low-power consumption, high-performance and high portability of complex engineering software. The system is demonstrated with cost estimation of molded parts. A knowledge set for the injection molding process is formalized in XML and a knowledge-base is constructed. The system is tested with examples, which illustrate the capability of our system for engineering applications.Article Outline1. Introduction2. Development of embedded knowledge-base system2.1. Knowledge representation2.1.1. Frame structure2.1.2. XML-based persistent knowledge description2.2. System features and structure2.2.1. System architecture2.2.2. Hardware components2.2.3. Software components. Kernel. XML parser. HTTP server. CAD server2.2.4. Knowledge-base and database implementation3. Illustrative example: cost estimation of molded parts3.1. Analysis of problem domain3.1.1. Process model3.1.2. Economics model3.2. Knowledge acquisition3.3. Knowledge-base construction3.4. Testing3.4.1. Analysis of the system3.4.2. Performance3.4.3. Test4. ConclusionsRewriting the Web with ChickenfootNo Code RequiredOn the desktop, an application can expect to control its user interface down to the last pixel, but on the World Wide Web, a content provider has no control over how the client will view the page, once delivered to the browser. This creates an opportunity for end users who want to automate and customize their Web experiences, but the growing complexity of Web pages and standards prevents most users from realizing this opportunity. This chapter describes Chickenfoot, a programming system embedded in the Firefox Web browser, which enables end users to automate, customize, and integrate Web applications without examining their source code. One way Chickenfoot addresses this goal is a technique for identifying page components by keyword pattern matching. We motivate this technique by studying how users name Web page components, and present a heuristic keyword matching algorithm that identifies the desired component from the users name. We describe a range of applications that have been created using Chickenfoot and reflect on its advantages and limitations.Chapter Outline?Introduction?Transforming a Web sites appearance?Automating repetitive operations?Integrating multiple Web sites?Chickenfoot?Language?Pattern matching?Clicking?Form manipulation?Other input?Navigation and page loading?Page modification?Widgets?Development environment?Security?Keyword matching algorithm?User study of keyword matching?Method?Results?Applications?Highlighting vocabulary words?Sorting tables?Concatenating a sequence of pages?Integrating a bookstore and a library?Making a bug tracker more dynamic?Adding faces to Webmail?Discussion?Future work?Related work?Summary?AcknowledgmentsInternet-based preliminary highway construction cost estimating database?Automation in ConstructionConceptual estimate is often misleading because of the paucity of available information. An accurate range of preliminary cost estimates with desired confidence bounds is essential to determine the viability of a project. In particular, better prediction of future costs using historical data could permit better decisions and eliminate errors. This research aims to develop a system architecture for a preliminary cost estimation system that toggles project input information, predictive item-level quantity, and segregates unit price of highway projects. Item-level quantity models at project outset were developed using cost data that are stored in Texas Department of Transportation (TxDOT) Design and Construction Information System (DCIS). The basic estimating parameters were derived from statistical analyses and then documented so that the data with the system could be continuously updated. The statistical models are embedded in a Web-based relational database management system (RDBMS). These models are then used for computation and data storage purposes. The system has proved to reduce cost estimates variability and to eliminate the need of ad-hoc housekeeping by centralized maintenance. This application was developed by using open-source software including PHP (PHP Hypertext Preprocessor), APACHE server, and MySQL database server with the usage of browser interface that further reduces the cost of development and maintenance.Advanced data acquisition system for SEVAN?/Advances in Space ResearchHuge magnetic clouds of plasma emitted by the Sun dominate intense geomagnetic storm occurrences and simultaneously they are correlated with variations of spectra of particles and nuclei in the interplanetary space, ranging from subtermal solar wind ions till GeV energy galactic cosmic rays. For a reliable and fast forecast of Space Weather world-wide networks of particle detectors are operated at different latitudes, longitudes, and altitudes. Based on a new type of hybrid particle detector developed in the context of the International Heliophysical Year (IHY 2007) at Aragats Space Environmental Center (ASEC) we start to prepare hardware and software for the first sites of Space Environmental Viewing and Analysis Network (SEVAN). In the paper the architecture of the newly developed data acquisition system for SEVAN is presented. We plan to run the SEVAN network under one-and-the-same data acquisition system, enabling fast integration of data for on-line analysis of Solar Flare Events. An Advanced Data Acquisition System (ADAS) is designed as a distributed network of uniform components connected by Web Services. Its main component is Unified Readout and Control Server (URCS) which controls the underlying electronics by means of detector specific drivers and makes a preliminary analysis of the on-line data. The lower level components of URCS are implemented in C and a fast binary representation is used for the data exchange with electronics. However, after preprocessing, the data are converted to a self-describing hybrid XML/Binary format. To achieve better reliability all URCS are running on embedded computers without disk and fans to avoid the limited lifetime of moving mechanical parts. The data storage is carried out by means of high performance servers working in parallel to provide data security. These servers are periodically inquiring the data from all URCS and storing it in a MySQL database. The implementation of the control interface is based on high level web standards and, therefore, all properties of the system can be remotely managed and monitored by the operators using web browsers. The advanced data acquisition system at ASEC in Armenia was started in November, 2006. The reliability of the multi-client service was proven by continuously monitoring neutral and charged cosmic ray particles. Seven particle monitors are located at 2000 and 3200?m above sea level at a distance of 40 and 60?km from the main data server.Article Outline1. Introduction2. Advanced data acquisition system2.1. Frontend computers2.2. Unified readout and control server2.3. URCS operator frontendReferencesExplaining answers from the Semantic Web: the Inference Web approach?Web Semantics: Science, Services and Agents on the World Wide WebThe Semantic Web lacks support for explaining answers from web applications. When applications return answers, many users do not know what information sources were used, when they were updated, how reliable the source was, or what information was looked up versus derived. Many users also do not know how implicit answers were derived. The Inference Web (IW) aims to take opaque query answers and make the answers more transparent by providing infrastructure for presenting and managing explanations. The explanations include information concerning where answers came from (knowledge provenance) and how they were derived (or retrieved). In this article we describe an infrastructure for IW explanations. The infrastructure includes: IWBase an extensible web-based registry containing details about information sources, reasoners, languages, and rewrite rules; PML the Proof Markup Language specification and API used for encoding portable proofs; IW browser a tool supporting navigation and presentations of proofs and their explanations; and a new explanation dialogue component. Source information in the IWBase is used to convey knowledge provenance. Representation and reasoning language axioms and rewrite rules in the IWBase are used to support proofs, proof combination, and Semantic Web agent interoperability. The Inference Web is in use by four Semantic Web agents, three of them using embedded reasoning engines fully registered in the IW. Inference Web also provides explanation infrastructure for a number of DARPA and ARDA projects.Article Outline1. Introduction2. Background and related work3. Requirements3.1. Support for knowledge provenance information3.2. Support for reasoning information3.3. Support for explanation generation3.4. Support for proof presentation4. Use cases5. Inference Web5.1. PML proof elements5.2. PML provenance elements5.3. IWBase5.4. Proof abstractor API5.5. Browser5.6. The explanation dialogue component6. Contributions and future work7. ConclusionAcknowledgementsSolving the startup problem in Western mobile Internet markets? Telecommunications PolicyThis paper describes the evolution of the mobile Internet in terms of three concepts: the startup problem, standard setting, and mental models. Products in which there is little or no value to the first users due to the existence of strong direct (e.g., telephone) or indirect (complementary products) network effects face a large startup problem. This paper divides the startup problem for the mobile Internet into two stages. Japanese and later other service providers solved the first startup problem with entertainment content that was supported by a micro-payment system (service providers collect and pass on content fees to content providers) and custom phones that displayed this content in a consistent manner.Western service providers were slow to introduce micro-payment systems and entertainment content due to their initial focus on business users, which reflected their mental models. Mental models, which can also be thought of as shared beliefs or values, are typically based on historical experience as opposed to current knowledge of the environment and often prevent the development of new business models or new perceptions of foreign markets. Western service providers were slow to obtain phones that display content in a consistent manner because manufacturers were unable to agree on content and other standards in the wireless application protocol (WAP) Forum and subsequently have been slow to provide service providers wit