• The Transactions of the Korea Information Processing Society
• /
• v.7 no.3
• /
• pp.831-841
• /
• 2000

For the operation of the practical software systems, the development, extension and modification phases are successively needed through the new requirements added and their errors debugging detected. Therefore, if it is possible to integrated the reusable software components and to reorganize them into the new software systems, we can improve the productivity, quality, and cost-effectiveness for he development of software systems. For these reasons, it will be required to research and develop methodology and tools for programs integration which make some programs merged effectively. In the process of merging two versions of a program into one, we can consider that some parts of the two versions are equivalent under the non-interference between them. According to the previous studies the program selected to determine the criterion of non-interference between them. According to the previous studies the program selected to determine the criterion of non-interference was very large, so we have difficulty in integrating many programs practically. In this paper, we propose a new improved algorithm which can reduce the related program size of non-interference criterion yb use of dynamic slicing techniques for integration of two versions of a program, and prove the efficiency of the proposed algorithm by showing some examples.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.8
• /
• pp.1987-1994
• /
• 1997

ATM switching software should be required high reliability, functionality, extendability and maintainability. After development of the software, it is verified and tested by analyzer whether the software is accomplished the characteristics of it or not. There are so many CASE tools in other area, but the CHILL testing tools that can verify ATM softwares have not various functions are not many. In this paper we develop the testing tool which can evaluate and test CHILL programmed ATM software. This Tool supports testing reports, debugging informations and maintenance informations including parallel process about CHILL original programs.

• Journal of KIISE:Computing Practices and Letters
• /
• v.5 no.3
• /
• pp.313-325
• /
• 1999

분산 프로그램의 디버깅이 순차 프로그램의 디버깅보다 어려운 이유중의 하나는 수행중인 프로세스들 간의 통신 때문이다. 비록 분산 시스템을 위해 구축된 디버거들이 많이 있음에도 불구하고 , 프로세스들간의 통신 이벤트를 효과적으로 디버깅할수 있는 실용적인 수준의 디버거는 없는 실정이다. 본 논문에서는 분산 시스템의 개발에 널리 사용되고있는 RPC 매커니즘을 이용한 프로그램간의 통신을 효과적으로 디버깅하는 방법을 제시한다. 이를 위하여 RPC 통신 이벤트를 디버깅 객체로 정의한 RPC 이벤트 모델을 제안하고 이에 기초하여 RPC 이벤트 추적 기능을 설계 및 구현하였다. RPC 프로토콜을 분석한 결과를 이용하여 메시지의 송.수신 이벤트를 추적 기능을 설계 구현하였다. RPC 프로토콜을 분석한 결과를 이용하여 메시지의 송.수신 이벤트를 라이브러리 함수의 호출과 자료의 값으로 기술하고 해당라이브러리 함수의 호출이 발생한 위치를 인지함으로써 모든 통신 이벤트의 발생을 탐지할수 있었다. 제안된 RPC 이벤트 추적기능은 현재 분산 디버거인 유니뷰 시스템에 구현되었다. 이벤트 추적 기능의 추가적 구현으로 인하여 유니뷰 시스템은 추적된 통신의 내용을 보면서 관련된 소스 코드를 보거나 프로그램을 제어하고 원격 함수 호출에 사용된 매개변수의 값을 보는 등의 행위가 가능하다. 또한 이러한 이벤트 추적기능을 수행하기 위하여 별도의 라이브러리나 수행환경이 요구되지 않으므로 실제분산시스템의 개발 환경에 적응하기가 용이한 장점을 가진다.

• Proceedings of the KIEE Conference
• /
• 2003.07d
• /
• pp.2540-2542
• /
• 2003

This paper presents an internet-based self-learning educational system which can be enhancing efficiency in the learning process of Java language. The proposed self-learning educational system is called Java Web Player(JWP), which is a Java application program and is executable through Java Web Start technologies. In this paper, three important sequential learning processes : concept learning process, programming practice process and assessment process are integrated in the proposed JWP using Java Web Start technologies. This JWP enables the learners to achieve efficient and interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of educational technologies. Also, online voice presentation and its related texts together with moving images are synchronized for efficient language learning process. Furthermore, a simple/useful compiler is included in the JWP for providing language practice environment such as coding, editing, executing and debugging Java source files. Finally repeated practice can make the learners to understand easily the key concepts of Java language. Simple multiple choices are given suddenly to the learners while they are studying through the JWP and the test results are displayed on the message box.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.40 no.6
• /
• pp.548-554
• /
• 2012

Verification and validation of operational software of the flight control computer, which is flight safety critical, is very important to prove correctness and faultness of the software. To verify the real-time softare requirement on operational software of flight control computer, real-time software internal parameter and variable monitoring technics on hardware-in-the-loop environment, similar to on-flight environment, is required. This paper describes flight safety critical software validation and verificiation environment using standard debugging interface, NEXUS 5001.

• Journal of Electrical Engineering and Technology
• /
• v.9 no.2
• /
• pp.576-588
• /
• 2014

The superiority of CMI (Cascaded Multilevel Inverter) is unparalleled in high power and high voltage STATCOM (Static Synchronous Compensator). However, the parameters and operating conditions of each individual power unit composing the cascaded STATCOM differ from unit to unit, causing unit voltage disequilibrium on the DC side. This phenomenon seriously impairs the operation performance of STATCOM, and thus maintaining the DC voltage balance and stability becomes critical for cascaded STATCOM. This paper analyzes the case of voltage disequilibrium, combines the operation characteristics of the cascaded STATCOM, and proposes a new DC voltage control scheme with the advantages of good control performance and stability. This hierarchical control method uses software to achieve the total active power control and also uses chopper controllers to enable that the imbalance power can flow among the capacitors in order to keep DC capacitor voltages balance. The operating principle of the chopper controllers is analyzed and the implementation is presented. The major advantages of the proposed control strategy are that the number of PI regulators has been decreased remarkably and accordingly the blindness of system design and debugging also reduces obviously. The simulation reveals that the proposed control scheme can achieve the satisfactory control goals.

• The KIPS Transactions:PartD
• /
• v.16D no.2
• /
• pp.213-222
• /
• 2009

Traceability has been held as an important factor in testing activities as well as model driven development. Vertical traceability affords us opportunities to improve manageability from models and test cases to code in testing and debugging phase. Traceability also overcomes difficulties by the separation between abstraction levels when we trace errors from models to source code after test. To support a rigorous test this paper proposes XML based traceability which vertically trace from model and test case to source code. This paper explains how the traceability works and finds out error spots Through experiments using a concrete example.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.4
• /
• pp.706-714
• /
• 2008

In this paper, we suggest a practical and flexible system architecture for JTAG(Joint Test Action Group) protection of application processors. From the view point of security, the debugging function through JTAG port can be abused by malicious users, so the internal structures and important information of application processors, and the sensitive information of devices connected to an application processor can be leak. This paper suggests a system architecture that disables computing power of computers used to attack processors to reveal important information. For this, a user authentication method is used to improve security strength by checking the integrity of boot code that is stored at boot memory, on booting time. Moreover for user authorization, we share hard wired secret key cryptography modules designed for functional operation instead of hardwired public key cryptography modules designed for only JTAG protection; this methodology allows developers to design application processors in a cost and power effective way. Our experiment shows that the security strength can be improved up to $2^{160}{\times}0.6$second when using 160-bit secure hash algorithm.

• Journal of KIISE:Computing Practices and Letters
• /
• v.6 no.1
• /
• pp.93-102
• /
• 2000

Processors for a base station controller such as call control processor have to serve usersdemand. Some of processors have been still used for the processing of call and 0&M (operation and maintenance) management by adopting embedded board type. This type can not provide users with a wide variety of environments for testing and debugging. User environments are regarded as a primary system factor in most systems and this is particularly so in designing and implementing the processor for base station controller in mobile communication systems. We describe the design and implementation of new user environment tool named QUEST for the next generation mobile communication system, IMT-2000. The simulation results of performance evaluations demonstrate that our system performs well for a base station controller without performance degradation.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2004.05a
• /
• pp.709-713
• /
• 2004

This Paper Presents an Internet-based Java self-learning educational system which consists of a management system named Java Web Player (JWP) and creative multimedia contents fer Java language. The JWP Is a Java application program free from security problems by the Java Web Start technologies that supports an Integrated learning environment including three Important learning Procedures: Java concept learning Process, Programming practice process and assessment process. This JWP enables the learners to achieve efficient and Interesting self-learning since the learning process is designed to enhance the multimedia capabilities on the basis of various educational technologies. On-line voice presentation and its related texts together with moving images are synchronized for efficiently conveying creative contents to learners. Furthermore, a simple and useful compiler is included in the JWP fur providing user-friendly language practice environment enabling such as coding, editing, executing and debugging Java source files on the Web. The assessment process with various items helps the learners not only to increase their academic capability but also to appreciate their current degree of understanding. Finally, simple multiple choices are given suddenly to the learners while they are studying through the JWP and the test results are displayed on the message box. The proposed system can be used for an efficient tool for learning system on the Web.