• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.8
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• pp.4174-4190
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• 2019

IEC 62304 is a standard for the medical device software lifecycle. Developers must develop software that complies with all specifications in the standard for licensing. However, because the standard contains not only a large number of specifications, but also domain-specific information and association relationships between specifications, it requires considerable effort and time for developers to understand and interpret the standard. To support developers, this paper presents a method for extracting the contents of the IEC 62304 standard as a goal model, which is the core methodologies of requirements engineering. The proposed method analyzes the grammar of the standard to robustly extract complex structures and various information from standard specifications and define rules that extract goals and links from syntactic element units. We validated the actual extraction process for the standard document experimentally. Based on the extracted goal model, developers can intuitively and efficiently comply with the standard and track specific information within the medical software and standard domains.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.226-231
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• 2008

40 Gbps WDM Systems using super-Gaussian RZ pulses have been studied by numerical simulation to optimize their performance. The assumption of standard single mode fiber is valid when existing WDM systems are required to upgrade their performance to 40Gbps. It is shown that the standard single mode fiber can transmit optical signals over 720 km (Q > 10) by optimizing optical and electrical filter characteristics at the receiver and by compensation of dispersion. However, it is also shown that ${\pm}0.3%$ dispersion compensation tolerance per span (80 km) could prohibit transmitting over 320km (Q > 10). In addition, a duty cycle of less than 0.4 degrades system performance significantly.

• Journal of Aerospace System Engineering
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• v.9 no.2
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• pp.63-71
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• 2015

An aircraft engine is considered as the most important element among aircraft systems. Thus type certificate is required for an aircraft engine to ensure its safety under appropriate airworthiness standard. U.S. FAR Part 33 or European CS-E is widely adopted as an airworthiness standard for aircraft engines, and other representative countries of the world established own airworthiness standards under their regulations. In this paper, we compared differences of the requirements between FAR Part 33 and CS-E, and proposed the rulemaking items to harmonize Korean Airworthiness Standard for Aircraft Engines with worldwide standards and to contribute to growth of aviation industry.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.11-27
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• 1995

This study sets a goal of establishing work standard and standard time in a machine tool process consisted of high-priced NC machine tools. Firstly, the theories of work standard and standard time in the field of NC machine tools are studies. Secondly, the theories are actually applied to a manufacturing company; work standard sheets are developed and applied to a machining center haying low operation rate, and then the increase in productivity is compared. Finally, problems to be studied later in relation to work standard and standard time are presented.

• Journal of the Korean Society of Safety
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• v.36 no.5
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• pp.79-85
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• 2021

A standard engineering model that reflects the current organization system and engineering operation process of domestic nuclear power plants was developed based on the Standard Nuclear Performance Model developed by the American Nuclear Energy Association. The level 0 screen, which is the main screen of the engineering model computer system, consisted of an object tree structure, which provided information that is phased down from a higher structure level to a lower structure level (i.e., level 3). The level 1 screen provided information related to the sub-process of the engineering operation, whereas the Level 2 screen provided information related to each engineering operation activity. In addition, the Level 2 screen provided additional functions, such as linking electronic procedures/guidelines, providing electronic performance forms, and connecting legacy computer systems (such as total equipment reliability monitoring system, configuration management systems, technical information systems, risk monitoring systems, regulatory information, and electronic drawing system). This screen level increased the convenience of user's engineering tasks by implementing them. The computerization of an engineering model that connects the entire engineering tasks of an establishment enables the easy understanding of information related to the engineering process before and after the operation, and builds a foundation for the enhancement of the work efficiency and employee capacity. In addition, KHNP developed an online training module, which operates as an e-learning process, on the overview and utilization of a standard engineering model to expand the understanding of standard engineering models by plant employees and to secure competitiveness.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.4
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• pp.430-438
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• 2007

In the current RFID (Radio Frequency IDentification) middleware systems based on the EPCglobal standard, the tag data received by multiple readers are processed sequentially in FIFO (First In First Out) order. Considering the priority of RFID reader makes the RFID system more flexible and improve the data transaction throughput in the service environment where important tag data with high priority for a specific reader. In this study, we propose a new RFID middleware system architecture supporting priority service with the Buffer Management Component. Our proposals are compliant with the EPCglobal ALE (Application Level Events) standard interface for middleware systems and their clients. To verify the efficiency of this proposed system, simulation is used for evaluation.

• Transactions on Control, Automation and Systems Engineering
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• v.3 no.3
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• pp.164-169
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• 2001

This paper considers the problem of robust stabilization and disturbance attenuation for a class of uncertain singularly perturbed systems with norm-bounded nonlinear uncertainties. It is shown that the state feedback gain matrices can be determined to guarantee the stability of the closed-loop system for all $\varepsilon$$\in$(0, $\infty$). Based on this key result and some standard Riccati inequality approaches for robust control of singularly perturbed systems, a constructive design procedure is developed.

• Korean Journal of Computational Design and Engineering
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• v.17 no.4
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• pp.225-233
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• 2012

A comprehensive research effort in order to develop and disseminate modernized Korean housing (Hanok) has recently been initiated by Korean government. This large scale research project encompasses a wide spectrum of housing development including public policy, architectural plans, modules, construction materials and methods, prefabricated assemblies, automated production, construction management, and advanced information systems. For the purpose of integrating and automating the whole processes from an industry perspective, it is of great importance to develop a standard classification system and project numbering system (PNS) for the modernized Korean housing. This paper focuses on the standard classification systems and PNS for cost and schedule control. The distinct characteristics and managerial requirements were explored and embedded into the proposed classifications for modernized Hanok.

• Journal of the Korea Safety Management & Science
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• v.15 no.3
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• pp.61-69
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• 2013

According to ISO 26262 (the international standard on functional safety for automotive industry), the functional safety should be considered during the whole automotive systems life cycle from the design phase throughout the production phase. In order to satisfy the standard, the automotive and related industry needs to take appropriate actions while carrying out a variety of development activities. This paper presents an approach to coping with the standard. Analyzing the standard indicates that the safety issues of the automotive systems should be handled with a system's view whereas the conventional approach to solving the issues has been practiced with focus on the component's level. The aforementioned system's view implies that the functional safety shall be incorporated in the system design from both the system's life-cycle view and the hierarchical view for the structure. In light of this, the systems engineering framework can be quite appropriate in the functional safety development and thus has been taken in this paper as a problem solving approach. Of various design issues, the analysis and verification of the safety requirements for functional safety is a key study subject of the paper. Note, in particular, that the conventional FMEA (failure mode effects analysis) and FTA (fault tree analysis) methods seem to be partly relying on the insufficient experience and knowledge of the engineers. To improve this, a systematic method is studied here and the result is applied in the design of an ABS braking system as a case study.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.9
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• pp.1618-1625
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• 2016

Electric motor systems account for more than half of all electric systems and the amount of energy consumption of those is almost 70 percent of total energy consumption of electric motor systems in industry. As electric motor systems are very responsible for global electricity savings and environment protection. Many international organizations are supporting standards and policy development processes to improve the efficiency of electric motor systems. Many standards are being developed at technical committee of IEC that has been required in order to support the implementation of efficiency regulations. High efficiency standards and levels for electric motor systems are slowly being introduced and compulsory in many countries. Therefore understanding the international efficiency evaluation standards and the regulation of electric motor systems of each country is important. This paper presents the current status and trends of international evaluation standards and regulations about the efficiency of electric motor systems.