• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1467-1473
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• 2004

It requires different safety programs from those of the typical train control systems to develop AGT systems applying train control system based on communication technology. Especially Advanced LRT system involves the processes that have the various safety functions being conducted by softwares and also have characteristics that should have special interest in validation of interface specification. The core items for the safety engineering for LRT control systems are hardware & software engineering, safety-critical system safety engineering, application software validation & verification technologies. In this paper the trends of the technologies for the mentioned core-items are described.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1992년도 학술강연회
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• pp.33-45
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• 1992

The sanitation inspection is the most frequently used procedure to protect foods prepared in foodservice establishments. In order to enhance foodservioe inspections and to improve post-inspection remedial measures, more practical evaluation methods for sanitation are required. The HACCP approach is based upon factors which contribute to foodborne disease rather than on factors which relate to aesthetics. Contributing factors for foodborne disease from foodservice establishments reported in USA, Canada, and England were analyzed to identify potential hazards during practical foodservioe operations. Hazards were classified at critical control points by risk ranking. Twenty-two observable practical indicators relating to each contributing factor were selected and adjusted to standardized procedures and hazard determiners at critical contral points. The weights for each inspection item were ranked as 1, 2, 3, 4 or 5 according to the risk level of contributing factors. And also application for the inspection item in different 6 types of work procedures was suggested for the use of specialized foodservice establishment and cafeteria, and of manager's self inspection in each establishment.

• 대한안전경영과학회지
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• 제16권4호
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• pp.11-19
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• 2014

Modern systems development becomes more and more complicated due to the need on the ever-increasing capability of the systems. In addition to the complexity issue, safety concern is also increasing since the malfunctions of the systems under development may result in the accidents in both the test and evaluation phase and the operation phase. Those accidents can cause disastrous damages if explosiveness gets involved therein such as in weapon systems development. The subject of this paper is on how to incorporate safety requirements in the design of safety-critical systems. As an approach, a useful system structure using the method of design structure matrix (DSM) is studied while reflecting the need on systems safety. Specifically, the effects of system components failure are analyzed and numerically modeled first. Also, the system components are identified and their interfaces are represented using a component DSM. Combining the results of the failure analysis and the component DSM leads to a modified DSM. By rearranging the resultant DSM, a modular structure is derived with safety requirements incorporated. As a case study, application of the approach is also discussed in the development of a military UAV plane.

• 대한임베디드공학회논문지
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• 제16권6호
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• pp.267-276
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• 2021

The automotive industry and academic research have been continuously conducting research on standardization such as AUTOSAR (AUTomotive Open System ARchitecture) and ISO26262 to solve problems such as safety and efficiency caused by the complexity of electric/electronic architecture of automotive. AUTOSAR is an automotive standard software platform that has a layered structure independent of MCU (Micro Controller Unit) hardware, and improves product reliability through software modularity and reusability. And, ISO26262, an international standard for automotive functional safety and suggests a method to minimize errors in automotive ECU (Electronic Control Unit)s by defining the development process and results for the entire life cycle of automotive electrical/electronic systems. These design methods are variously applied in representative automotive safety-critical systems. However, since the functional and safety requirements are different according to the characteristics of the safety-critical system, it is essential to research the AUTOSAR functional safety design method specialized for each application domain. In this paper, a software functional safety mechanism design method using AUTOSAR is proposed, and a new failure management framework is proposed to ensure the high reliability of the product. The AUTOSAR functional safety mechanism consists of memory partitioning protection, timing monitoring protection, and end-to-end protection. The fault management framework is composed of several safety SWCs to maintain the minimum function and performance even if a fault occurs during the operation of a safety-critical system. Finally, the proposed method is applied to the Shift-by-Wire system design to prove the validity of the proposed method.

• Nuclear Engineering and Technology
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• 제31권1호
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• pp.49-57
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• 1999

It has been a critical issue to predict the safety critical software reliability in nuclear engineering area. For many years, many researches have focused on the quantification of software reliability and there have been many models developed to quantify software reliability. Most software reliability models estimate the reliability with the failure data collected during the test assuming that the test environments well represent the operation profile. User's interest is however on the operational reliability rather than on the test reliability. The experiences show that the operational reliability is higher than the test reliability. With the assumption that the difference in reliability results from the change of environment, from testing to operation, testing environment factors comprising the aging factor and the coverage factor are developed in this paper and used to predict the ultimate operational reliability with the failure data in testing phase. It is by incorporating test environments applied beyond the operational profile into testing environment factors. The application results show that the proposed method can estimate the operational reliability accurately.

• 대한안전경영과학회지
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• 제9권6호
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• pp.171-179
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• 2007

The objective of this GM Red-X project was to reduce customer complaints on Kalos, Lacetti, Magnus as reported through 2004.1 - 2005.1 warranty performance. Seatbelt alarm lamp mal-function problem is connected with safety. So it is critical issue. Seatbelt alarm lamp mal-function which caused by buckle occurred 22 cases from 2004.1 to 2005.1.

• Nuclear Engineering and Technology
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• 제39권4호
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• pp.349-358
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• 2007

A single-beam gamma densitometer is utilized to measure the average void fraction in a small diameter stainless steel pipe under critical flow conditions. A typical design of a single-beam gamma densitometer is composed of a sealed gammaray source, a collimator, a scintillation detector, and a data acquisition system that includes an amplifier and a single channel analyzer. It is operated in the count mode and can be calibrated with a test pipe and various types of phantoms made of polyethylene. A good average void fraction is obtained for a small diameter pipe with various flow regimes of the core, annular, stratified, and bubbly flows. Several factors influencing the performance of the gamma densitometer are examined, including the distance between the source and the detector, the measuring time, and the ambient temperature. The void fraction is measured during an adiabatic downward two-phase critical flow in a vertical pipe. The test pipe has an inner diameter of 10.9 mm and a thickness of 3.2 mm. The average void fraction was reasonably measured for a two-phase critical flow in the presence of nitrogen gas.

• 시스템엔지니어링학술지
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• 제15권2호
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• pp.108-115
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• 2019

The activities of managing and controlling the configuration of a system component over its life cycle are critical tasks in developing a high safety system as well as general system development. These configuration management activities should be defined through the management plan at the beginning of the life cycle, and should be performed continuously and systematically until the end of the project after the system or product development is completed. In this study, the configuration management process applied in the development of high safety railway signaling system was introduced and an efficient application proposals of it was proposed. In particular, configuration management through the establishment of a configuration management system based on computer tools is one of the important activities of maintaining the configuration integrity of the system or product.

• Journal of Multimedia Information System
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• 제3권3호
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• pp.69-76
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• 2016

Currently, research on more convenient and safer cars for drivers and passengers, the intelligent cars, are being actively conducted. The researches involve designing systems that intelligently minimize physical damages caused by car accidents, not just pursuing passive safety measures like airbags or safety belts. However, there are many cases around the world where airbags cannot be activated in times of accidents and it is difficult for consumers to check if their airbags will be activated, especially for the old-style cars. Thus, in this paper, a base technology for an application that can determine whether the airbags will actually be actuated at a critical moment based on the mechanical calculations is being introduced.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3505-3516
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• 2021

During nuclear facility decommissioning, workers are continuously exposed to high-level radiation. Hence, adequate path planning is critical to protect workers from unnecessary radiation exposure. This work discusses recent development in radioactive path planning and the algorithms recommended for the task. Specifically, we review the conventional methods for nuclear decommissioning path planning, analyze the techniques utilized in developing algorithms, and enumerate the decision factors that should be considered to optimize path planning algorithms. As a major contribution, we present the quantitative performance comparison of different algorithms utilized in solving path planning problems in nuclear decommissioning and highlight their merits and drawbacks. Also, we discuss techniques and critical consideration necessary for efficient application of robots and robotic path planning algorithms in nuclear facility decommissioning. Moreover, we analyze the influence of obstacles and the environmental/radioactive source dynamics on algorithms' efficiency. Finally, we recommend future research focus and highlight critical improvements required for the existing approaches towards a safer and cost-effective nuclear-decommissioning project.