A continuous-switching type array antenna receiver has been proposed in order to reduce the deterioration due to fast-fading channel variations and improve communication performance. The receive antennas are placed in a linear array, and by sequentially switching the elements in the opposite direction to the direction of the train travel, it has been possible to fix the signal receiving point virtually. Through the development of a scale-model experiment of high-speed movement using the prototype antenna, in this paper we show that it is possible through optimized antenna element selection and appropriate signal processing to reduce the fading rate and improve the performance of an OFDM system. A software simulation based on the Worldwide Interoperability for Microwave Access (WiMAX) physical layer parameters was made and data transmitted at RF in a 5 MHz bandwidth with symbol rate appropriately scaled to simulate a range of fading speeds. The receive antenna array consisting of eight elements traverses a track at a virtual speed of 180 km/h and the error rate performances with and without switching are compared.

We propose an XML C source code representation to support developing CASE tools. Since source code is a main artifact of software development, most CASE tools have some features related to source code editor, static analyzer, profiler, etc. To develop such tools, detailed information related to source code is needed. However, it is quite difficult to reuse program analysis features because they do not have common interfaces even for parsing and data/control-flow analysis that are most common features for such CASE tools. To address this issue, we focus on XML as an intermediate representation for source code information. Existing XML representations only represent structure of syntax trees and lack some important information required for CASE tools. We propose two models for representing source code, one is for intra-file information, which consists of syntax structure, flow, and type information, the other is for inter-file relation, which is cross-reference information. We also introduce CASE tools with our representation and demonstrate the efficacy in CASE tool development. To evaluate the efficacy, we show that a coding rule checker and a cross-referencer can be easily implemented using common XML processing libraries such as XSLT and XPath.

Software visualization with sequence diagrams is one of the promising techniques aimed at helping developers comprehend the behavior of object-oriented systems effectively. However, it is still difficult to understand this behavior, because the size of automatically generated sequence diagrams tends to be beyond the developer's capacity. In this paper, we propose a sequence diagram slicing method, which is an extension of our previous method based on a dynamic slicing technique using static information. Our proposed method is capable of accurate slice calculation based on high-precision data dependency and can support various programs, including exceptions and multithreading. In addition, our proposed new tool performs slice calculations on the Eclipse platform and we demonstrate the applicability of this method by applying the tool to two Java programs as case studies. The results confirm the effectiveness of our proposed method for understanding the behavior of object-oriented systems.

This paper briefly describes the theme and goals of the WebSDE Workshop on ASE'2006. This workshop emphasizes next-generation software development environments inspired by Web2.0 technologies and seeks to explore ways of automated support to software development in the Web2.0 era.