• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.2
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• pp.214-227
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• 2003

Developing an application, it is difficult to catch an exact requirement with the conventional text-based method. It has also problems in verification and analysis at each developing stage. Therefore, if an adjustment is required with an error and change of requirement, a bad effect happen in the whole system. In this case, it also affect adversely on the developing cost and period. Meanwhile, if an analysis or verification is performed, the possibility of an error frequency reduces. Thus, not only is it easier to correct the error but also add an new requirement. This thesis embody a TCP/IP congestion control algorithm with SDL which provides automatically graphic interface, verification and analysis to each developing stage. Using SDL gave a clear representation embodiment in each developing stage and easiness of adjustment due to changing requirements or correcting errors. In addition, the stages of protocol have been certified in a simulation by verification of MSC and the results showed a possibility of developing a better TCP/IP protocol.

• Journal of Electrical Engineering and Technology
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• v.4 no.1
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• pp.87-92
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• 2009

Many critical control systems are developed using formal methods. When software applied to such systems is developed, the employment of formal methods in the software requirements specification and verification will provide increased assurance for such applications. Earlier errors of overlooked requirement specification can be detected using the formal specification method. Also, the testing and full verification to examine all reachable states using model checking to undertake formal verification are able to be completed. In this paper, we proposed an eclectic approach to incorporate Z(Zed) formal language and 'Statemate MAGNUM', formal method tools using Statechart. Also we applied the proposed method to train control systems for the formal requirement specification and analyzed the specification results.

• Journal of the Korean Society of Systems Engineering
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• v.9 no.1
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• pp.47-53
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• 2013

The object of this study is to define systematically for outputs of Verification Process among the system life cycle process based on ISO/IEC 15288 for power supply system, which is one of the importance sub-systems to configure the LRT system. Furthermore, to prevent various problem in advance that can occur in the Transition LRT's power supply to be completed Integration. For this purpose, traceability of verification requirement and outputs. should be managed to use verification for system requirement and data processing tool. by system engineering techniques of system life cycle process based on ISO/IEC 15288 to LRT system.

• Proceedings of the KSR Conference
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• 2009.05b
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• pp.395-400
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• 2009

The HEMU-400X project starts at 2007. It is important first of all that describing correctly system requirement during configuration of system, design, manufacturing, installation and test verification so that the complicated high-speed electric multiple unit is to run safety and reliable and to achieve target performance and function properly. The system requirement assist the system designer to understand the performance and function of system in basic design. For this process, system engineer have to manage the system requirement. This paper proposes the management contents of system requirement such as change management, requirement traceability, etc, for HEMU-400X.

• Journal of the Korea Society for Simulation
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• v.18 no.3
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• pp.113-122
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• 2009

Software is getting more complex due to a variety of requirements that include desired functions and properties. Therefore, verifying and testing the software are complicated problems. Moreover, if the software is already implemented, inserting and deleting tracing/logging code into the source code may cause several problems, such as the code tangling and the code scattering problems. This paper proposes the Aspect DEVS Verification Framework which supports the verification and testing process. The Aspect DEVS Verification Framework utilizes Aspect Oriented Programming features to handle the code tangling and the code scattering problems. By applying aspect oriented features, a user can find and fix the inconsistency between requirement and implementation of a software without suffering the problems. The first step of the verification process is the building aspect code to make a software act as a generator. The second step is developing a requirement specification using DEVS diagrams and implementing it using the DEVSIM++. The final step is comparing the event traces from the software with the possible execution sequences from DEVS model.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1049-1052
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• 1999

As the Internet traffic increases, the demand for higher performance routers continues to grow, and it makes switch chips more complex. To make matters worse, these chips also need to handle high-level services. In this paper, we introduce an efficient verification methodology that can support real network traffics to satisfy the verification requirement of real complex situation even at the early design phase of switch chips.

• The Journal of the Korea Contents Association
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• v.8 no.5
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• pp.61-71
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• 2008

It is often claimed that the descriptive way of documentation is insufficient to define software requirements as being unambiguous. This is caused by not only the difference of knowledge and understanding of the stakeholder as to system but also the difference in the way of documentation like method of representation as well as depth of description. The study explains the process and results of applying a diagraming tool like UML to improve the requirements of GLORY(GLObal Resource management sYstem) initially defined in descriptive way. Especially, the result shows that the requirements are more accurately improved with the good hierarchies and well-leveled functionalities, with the help of diagraming tool, expecting easy maintenance of requirements and prevention of omission of requirements.

• Journal of the Korean Society for Railway
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• v.10 no.3 s.40
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• pp.365-371
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• 2007

The communication protocol for interface among railway signalling systems is designed and established as national standard in Korean from a few years ago. So the communication link for information transmission among railway signalling system can be a good example of application of this standard. Communication protocol which is standardized among Korean railway signalling is considered to apply information transmission. And we confirmed there is no the states of deadlock of livelock in std. protocol which is applied formal verification which is one of the analytic method for inspection of safety characteristics in the design course of protocol. But the safety of protocol has to necessarily accomplish this normal analysis approach about satisfying requirement matters with such this analytic approach. In this paper we analyzed the safety characteristics of standard protocol for Korean Railway signalling through the requirement matters for safety transmission of railway transmission system which is required in international standard. So through this study we confirm whether it satisfies safety requirement matters of the level which require in international standard and tried to confirm whether standard protocol has enough safety character in the real railway field.

• Current Optics and Photonics
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• v.7 no.4
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• pp.354-361
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• 2023

We present the optical design and experimental verification of resolving performance of a 3× long wavelength infrared (LWIR) zoom camera for drones. The effective focal length of the system varies from 24.5 mm at the wide angle position to 75.1 mm at the telephoto position. The design specifications of the system were derived from ground resolved distance (GRD) to recognize 3 m × 6 m target at a distance of 1 km, at the telephoto position. To satisfy the system requirement, the aperture (f-number) of the system is taken as F/1.6 and the final modulation transfer function (MTF) should be higher than 0.1 (10%). The measured MTF in the laboratory was 0.127 (12.7%), exceeds the system requirement. Outdoor targets were used to verify the comprehensive performance of the system. The system resolved 4-bar targets corresponding to the spatial resolution at the distance of 1 km, 1.4 km and 2 km.

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.1_2
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• pp.118-124
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• 2004

In this paper we propose a method for authenticating the application that is to be downloaded or updated in smart cards. Previous works have some drawbacks such as having a long verification delay or requiring a large amount of primary/secondary storage. We propose an efficient parameterized scheme by using the hash chain technique where the secondary storage requirement and verification delay of updating the application are O(k) and O(k＋n/k), respectively. Moreover, both the first storage requirement and verification delay of downloading the application are O(1).