Runtime Engine Research Articles

A Cost–Benefit Evaluation Server for decision support in e-business

Business organizations are often faced with decision situations in which the costs and benefits of some competing business specifications such as business offers, product specifications, or negotiation proposals need to be evaluated in order to select the best or desirable ones. In e-business, there is a need to automate the cost–benefit evaluation process to support decision making. This paper presents a general-purpose Cost–Benefit Evaluation Server (CBES) and its underlying Cost–Benefit Decision Model (CBDM), which models benefits in terms of costs and logical scoring and aggregation of preferences associated with products and services. The Server provides build-time tools for users to specify preference and cost information and a run-time engine to perform cost–benefit evaluations. A business scenario involving supplier selection and automated negotiation is given to illustrate the application of the Server and its four evaluation modes.

Building XML query forms and reports with XQForms

XQForms is the first generator of Web-based query forms and reports for XML data. XQForms takes inputs (i) an XML Schema that models the source data to be queried and presented, (ii) a declarative specification, called XQForm annotation, of the query forms and reports that will be generated, and (iii) a set of template presentation libraries. The output is a set of query form and report pages that provide automated query construction and report formatting so that the end users can query and browse the underlying XML data. XQForms separates content (given by the XML Schema of the source data), query form semantics (specified by the annotations) and presentation of the pages (provided by the template library). The system architecture is modular and consists of four main components: (a) a collection of query controls that generate query fragments based on the values that the end user submits via the query form page; a set of query controls makes up a query form; (b) a graphical user interface, called XQForms Editor, for building the annotations; (c) a compiler that creates the query form pages based on the annotations and the template presentation libraries; (d) a run-time engine that constructs the queries that are executed against the XML data, and creates the reports by rendering the results using the template presentation libraries. All the components of the system have been implemented and an online demonstration is available at http://www.db.ucsd.edu/xqforms/.

Setting the scene: playing digital director in interactive storytelling and creation

Interactive digital storytelling promises to be a new artistic discipline. But what does the artwork look like? And how much control does the artist have over the final result? By searching for the right answers, we draw several approaches from diverse fields such as filmmaking, game design, autonomous agents, psychology, and narrative intelligence. We first give a definition of interactive storytelling that includes a scope between authorship and emergent narrative, and present two example projects with different emphases. Then, we introduce a multi-level concept for an experimental stage that can be used to explore interactive storytelling at varying degrees of flexibility versus predetermination. Instead of inventing the ultimate virtual narrator, we suggest developing layers of run-time engines that allow authors to work with directions on each single layer separately—from selecting high-level dramatic structures down to directing animated actors. The concept of underlying models at each level is explained in detail by the example of a story model implementation. Further, we show variations of level adjustments causing graded degrees of semi-autonomy. First results of this experimental stage are presented, and the primary future tasks are pointed out.

Spektri-Sim: Interactive Simulation and Analysis of the Infrared Spectra of Diatomic Molecules

We have developed Spektri-Sim, a Windows-based software application designed for simulation and analysis of the infrared spectra of diatomic molecules. It offers an appealing alternative to the spreadsheet-based analysis of such spectra used in many physical chemistry laboratories. Spektri-Sim features a unique, visual approach for evaluating molecular constants in which the user interactively seeks the optimal fit of a simulated spectrum to the experimental spectrum. Using Spektri-Sim forces the user to consider the influence of the molecular constants and temperature on the features of the spectrum (e.g. band origin, rotational splittings, and intensity distribution). The program interface is described and results from student-acquired data are reported. Spektri-Sim is available, free-of-charge, by downloading compressed copies of the installation diskettes from http://carbon.indstate.edu/spektri-sim. The distribution includes the LabVIEW 5.1 Run-Time Engine, documentation (with a tutorial) in PDF format, and sample data for HCl, HBr, and CO. Spektri-Sim has been tested (and performs well) in the Windows 95/98 environment using 133-MHz Pentium or faster processors.

New security issues raised by open cards

The methods, languages and tools for developing a smart card system share some characteristics with those of the embedded domain. Until recently, smart card programs were written in hand coded native assembly language. All programs (drivers, operating system, libraries, applications) were developed as a monolithic piece of code burned in the smart card ROM. Therefore, not only are traditional card systems difficult to develop (low-level programming language, very reduced-feature microcontroller, specific code for every microprocessor) but they also cannot support any evolution of their applications since all the application code is burned forever with the runtime engine in the ROM. Moreover, the production of such a monolithic program dedicated to a specific hardware and with ad hoc functions for the application domain consumes most of the card development cycle. In order to issue a card application, it is required (i) to write precise specifications, (ii) to write or re-write the basic software (akin to an operating system) for possibly multiple platforms, (iii) to develop specific functions for the application, and (iv) to verify this software prior to deploying it on thousands or millions of cards. This process is timeconsuming and costly. Since defining specifications for products that will be available long after is risky, this process has been inadequate for the creation of new markets. As it requires a long time it also severely limits the ability of a card issuer to quickly deploy new applications in accordance with the market needs.

Fuzzy Logic Controllers: a Knowledge Based System View

Abstract We view fuzzy logic control technology as a high level language in which we can efficiently define and synthesize non-linear controllers for a given process. We contrast fuzzy Proportional Integral (PI) controllers with conventional PI and two dimensional sliding mode controllers. Then we compare the development of Fuzzy Logic Controllers (FLC) with that of Knowledge Based System (KBS) applications. We decompose the comparison into reasoning tasks (representation, inference, and control) and application tasks (acquisition, development, validation, compilation, and deployment). After reviewing the reasoning tasks, we focus on the compilation of fuzzy rule bases into fast access lookup-tables. These tables can be used by a simplified run-time engine to determine the FLC's crisp output for a given input.