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Chi-Cheng Chu, Jianzhong Mo, and Rajit Gadh ABSTRACT In this paper, a series of interface tests on interaction approach for the generation of geometric shape designs via multi-sensory user interface of a Virtual Reality (VR) based System is presented. The goal of these interface tests is to identify an effective user interface for VR based Computer-Aided Design (CAD) system. The intuitiveness of the VR based interaction approach arises from the use of natural hand movements/gestures, and voice commands that emulate the way in which human beings discuss geometric shapes in reality. In order to evaluate the proposed interaction approach, a prototypical VR-CAD system is implemented. A series of interface tests were performed on the prototypical systems to determine the relative efficiency of a set of potential interaction approach with respect to specific fundamental design tasks. The interface test and its results are presented in this paper.

SynchroPhasor measurement provides high resolution and time-synchronized data, which exposes the complex dynamics of the power systems across wide areas. Taking advantage of this technology, the Real-Time Dynamics Monitoring System (RTDMS ® ) Platform for on-line wide area dynamics monitoring has been developed by Electric Power Group. The platform utilizes an open and modular architecture and offers a suite of applications for real-time reliability monitoring, analysis and alarming. This paper provides an overview of the developed platform including system architecture, application function and visualization features.

OBJECTIVE: To explore the effects of several oral medications on the results of the 14C-urea breath test (UBT). METHODS: One hundred and twelve patients with chronic gastritis that had tested positive in a rapid urease test were enrolled in the present study and were randomly divided into six groups: 20 patients received 20 mg famotidine b.i.d., 16 patients received 30 mg lansoprazole q.d., 18 patients received 1000 mg sucralfate t.i.d., 20 patients received 50 mg teprenone t.i.d., 20 patients received 220 mg colloidal bismuth subcitrate b.i.d., and 18 patients received four tablets t.i.d. of wei-de-an, a traditional Chinese medicine. The 14C-urea breath test was performed before treatment, 7 days after beginning drug treatment and 7 days after the cessation of drug treatment. RESULTS: All medications, especially colloidal bismuth subcitrate, were influenced by the result of the UBT. Seven days after drug treatment, the negative conversion rate of the UBT was 45.0% (9/20) in the colloidal bismuth subcitrate group, 30.0% (6/20) in the famotidine group, 31.3% (5/16) in the lansoprazole group, 16.7% (3/18) in the sucralfate group, 5.0% (1/20) in the teprenone group and 27.8% (5/18) in the wei-de-an group. However, all values returned to positive again 1 week after withdrawal. The influence of famotidine on UBT was similar to that of lansoprazole (P > 0.05). There was no significant difference between the results of the first and the third UBT. CONCLUSIONS: The UBT is a reproducible, non-invasive method for identifying Helicobacter pylori, but many drugs can influence the result of the UBT, so it is necessary to suspend treatment with these drugs before carrying out the testing procedure.

Design for Assembly (DFA) is an important subset of concurrent engineering. It involves the assembly constrains while designing. Nowadays, many efforts are focusing on developing of DFA expert systems integrated with CAD. To satisfy the information requirements of these DFA expert systems, this paper puts forward a DFA-oriented assembly relation model composed of a Function Relation Model (FRM), Geometry Relation Model (GRM) and Connecting Relation Model (CRM). All these concepts are discussed in this paper, and a real product is taken as an example to show how to apply this model in DFA expert systems.

This paper describes the use of Real Time Dynamics Monitoring System (RTDMS®) for use with SynchroPhasor System Technology (SPST). Analysis of some major power blackouts in US and other countries have shown that monitoring power system status and dynamic transient events in real-time can enable the operators to identify deteriorating system conditions early and help them take preventative actions to avoid or reduce likelihood of blackouts. Using RTDMS to monitor the power system with SynchroPhasor technology is expected to improve reliability, provide wide area visibility over multiple control areas, and provide system operators with real-time measurement of key grid metrics, including phase angles, oscillation modes, energy and modal damping. These grid dynamics indicators cannot be obtained in real-time from the existing historic tools such as SCADA or State Estimators. The SPST has great potential for enhancing power system stability and increasing power transmission system capability through high speed response based controls. Given, the proper visualization and analysis tools, this technology can assist operators in avoiding major system disturbances like the North American blackouts that occurred in Western US on August 10, 1996 and in Northeast US and Canada on August 14, 2003. The paper will outline the use of RTDMS with SPST and describes how it enhances the visibility of the power system. The RTDMS is in use at several ISOs and utility locations in North America.

Design For Assembly/disassembly (DFA) allows systematic evaluations and analysis of product assembly and disassembly during the product design stage with the goal of reducing assembly costs, improving quality and shortening time to market. These evaluations include assemblability, disassemblability, part accessibility, and part layout [1]. With the growing availability and widespread use of high bandwidth network and Virtual Reality (VR) technologies, the issues involved with product assembly, disassembly may be addressed and resolved effectively in a collaborative virtual environment over the Internet. In this paper, an analysis on the framework and definition of a collaborative virtual assembly and disassembly system, called Motive3D [2, 3], is introduced and examined using Unified Modeling Language (UML) [4]. UML is an Object Management Group’s (OMG) standard for object-oriented analysis and software design method, which allows specifying, constructing, visualizing, and documenting a distributed software-intensive system. Carrying out systematic analysis on the Motive3D system using UML, we believe that it expedites system development and will be possible to expedite the product design cycle and enable the assembly and disassembly process over Internet, and thus reduce the assembly and disassembly process bottlenecks.Copyright © 2003 by ASME

We iniroduced a web-based assembly/disassembly system in this article, which is designed for e-commerce and teleeducation purpose. The system is characterized by automatic disassembly pathlsequence generation, multi-level deployment/rendering, partially ordered reliable delivery and a friendly web-based user interface.

State estimation is a critical functionality of energy management system (EMS) to provide power system states in real-time operations. However, problems such as failure to converge, prone to failure during contingencies, and biased estimates while system is under stressed condition occur so that state estimation results may not be reliable. The unreliable results further impact downstream network and market applications, such as contingency analysis, voltage stability analysis, transient stability analysis, system alarming, and unit commitment. Thus, operators may lose the awareness of system condition in EMS. This paper proposes a fully independent and one-of-a-kind system by integrating linear state estimator into situational awareness applications based on real-time synchrophasor data. With guaranteed and accurate state estimation solution and advanced real-time data analytic and monitoring functionalities, the system is capable of assisting operators to assess and diagnose current system conditions for proactive and necessary corrective actions. The architecture, building components, and implementation of the proposed system are explored in detail. Two case studies with simulated data from the subsystems of Electric Reliability Council of Texas (ERCOT) and Los Angeles Department of Water and Power (LADWP) are presented. The test results show the effectiveness and reliability of the system, and its value for real-time power system operations.