Feature location (FL) is an important activity for finding correspondence between software features and modules in source code. Although dynamic FL techniques are effective, the quality of their results depends on analysts to prepare sufficient scenarios for exercising the features. In this paper, we propose a technique for guiding identification of missing scenarios using the prior FL result. After applying FL, unexplored call dependencies are extracted by comparing the results of static and dynamic analyses, and analysts are advised to investigate them for finding missing scenarios. We propose several metrics that measure the potential impact of unexplored dependencies to help analysts sort out them. Through a preliminary evaluation using an example web application, we showed our technique was effective for recommending the clues to find missing scenarios.

We present CATG, an open-source concolic test generation tool for Java and its integration with TesMa, a model-based testing tool which automatically generates test cases from formal design documents. TesMa takes as input a set of design documents of an application under test. The design documents are provided in the form of database table definitions, process-flow diagrams, and screen definitions. From these design documents, TesMa creates Java programs for the feasible execution scenarios of the application. CATG performs concolic testing on these Java programs to generate suitable databases and test inputs required to test the application under test. A demo video of the tool is available at https://www.youtube.com/watch?v=9lEvPwR7g-Q.

Feature location is an activity to identify correspondence between features in a system and program elements in source code. After a feature is located, developers need to understand implementation structure around the location from static and/or behavioral points of view. This paper proposes a semi-automatic technique both for locating features and exposing their implementation structures in source code, using a combination of dynamic analysis and two data analysis techniques, sequential pattern mining and formal concept analysis. We have implemented our technique in a supporting tool and applied it to an example of a web application. The result shows that the proposed technique is not only feasible but helpful to understand implementation of features just after they are located.

The use of highly iterative software development methodologies, such as Agile and Lean, have been growing. However, these methodologies do not explicitly provide practices for managing and measuring software quality. This deficiency may prevent software development organizations in critical domains from transforming from traditional development to highly iterative development. These organizations may need to manage quality during development and may desire to compare with the quality of a large number of products produced in the past. In this paper, we focus on the reliability aspects of software quality and discuss the applicability of conventional reliability metrics to iterative development. First, we defined the general process structure in iterative development. Then, we present an associated quality evaluation scheme closely. Our experimental results indicate that traditional quality metrics were applicable to iterative development and that the iterative development achieved maturity sufficient for the commercial release.

Recently, critical incidents have occurred in complex IT systems. Thus, how to confirm the dependability of a system via dependability cases is becoming necessary. Information related to dependability is important knowledge that must be shared among stakeholders. However, in previous methods used to describe dependability cases, the relation between a dependability claim and responsibility cannot be clearly specified. Thus, since the cause investigation cannot be completed at the time of the incident, system knowledge could not fully be utilized. Hence, we propose a method to express a responsibility attribute for sharing information and attaining an agreement between stakeholders.

The aim of our research is to empirically analyze the impact of requirements trace ability quality to the productivity of the enterprise applications development. We analyze trace ability links of Requirements Specification Documents (RSDs) collected from the enterprise applications development. These RSDs are classified into two groups in terms of project performance. One group includes RSDs of significant cost overrun projects, another group includes RSDs of normal range cost projects. Our analysis revealed that high quality of trace ability in RSDs significantly reduces the cost overrun in the enterprise applications development.

This paper proposes structured location, a semiautomatic technique and its supporting tool both for locating features and exposing their structures in source code, using a combination of dynamic analysis, sequential pattern mining and formal concept analysis.

The Communications Research Laboratory (CRL), Tokyo, Japan, and the Telecommunication Network Laboratory Group, Nippon Telegraph and Telephone Corp., Tokyo, Japan, have developed a highly precise, very long baseline interferometry (VLBI) system using a high speed asynchronous transfer mode (ATM) network. The observed data is transmitted through a 2.488-Gbps ATM network [STM-16/OC-48] instead of being recorded onto magnetic tape. The system was specially designed for the Key Stone Project (KSP), a project begun in 1994 to measure crustal deformation in the Tokyo metropolitan area. Cross-correlation processing and data observations are carried out simultaneously by one operator. It takes about one hour to analyze the data after the observations and correlations are completed. In regular geodetic VLBI experiments run every other day for 24 h, a horizontal position uncertainty of about 2 mm and a vertical position uncertainty of about 10 mm were achieved. The system was designed to enable automated operation throughout the entire process. The results obtained are available to the public via the Internet at http:ksp.crl.go.jp. This system is a significant advance in VLBI and should provide more precise information about crustal deformation in the Tokyo metropolitan area.

800 Mbit/s digital transmission systems, using nonredundant three-level and four-level codes, have been studied as a means of providing an economically attractive digital transmission system. These systems have been designed to be compatible with a 60 MHz analog system in repeater spacing and repeater size, so as to be easily introduced into the existing network. These systems with 11 520 telephone channels, exceed the 60 MHz analog system in both capacity and economy. Due to repeater construction factors, it became clear that the three-level code is more suitable. This paper describes the design and performance of 800 Mbit/s digital transmission systems and repeaters.

The design and performance of an experimental 800 Mbit/s repeater for four-level digital transmission over a coaxial cable is described in this paper. The 800 Mbit/s digital system exceeds the 60 MHz analog system, both in capacity and in economy. The repeater is designed to operate in repeater housings located at 1.6 km maximum spacing to be compatible with the 60 MHz analog sytsem. A nonredundant four-level line code has been employed, using a newly developed quantized feedback dc restoration technique. The most important item in realizing the high-speed multilevel repeater is the reduction of intersymbol interference. A simple quantized feedback scheme and an adjustable three-tap transversal equalizer have been used to compensate for intersymbol interference. The experimental repeater has been tested for 1.1-1.7 km repeater spacings using 2.6/9.5 mm coaxial cable. The results show that an 800 Mbit/s repeater with 1.6 km maximum repeater spacing is feasible.