• Nuclear Engineering and Technology
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• v.27 no.3
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• pp.385-392
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• 1995

A software engineering process has been developed for the design of safety critical software for Wolsong 2/3/4 project to satisfy the requirement of the regulatory body. Among the process, this paper described the detail process of validation testing peformed to ensure that the software with its hardware, developed by the design group, satisfies the requirements of the functional specification prepared by the independent functional group. To perform the test, test facility and test software ore developed and actual safety system computer was connected. Three kinds of test cases, i.e., functional test performance test and self-check test were programmed and run to verify each functional specifications. Test failures ore fedback to the design group to revise the software and test result were analyzed and documented in the report to submit to the regulatory body. The test methodology and procedure were very efficient and satisfactory to perform the systematic and automatic test. The test results were also acceptable and successful to verify the software acts as specified in the program functional specification. This methodology can be applied to the validation of other safety-critical software.

• Journal of Digital Contents Society
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• v.18 no.2
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• pp.393-401
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• 2017

As the importance of software in various industry areas has been increased, the number of accidents related to software safety are growing up. The key industries such as railroads, aviation and medicine, recommend IEC 61508 and international safety standards for their own to achieve functional safety and reduce the issues caused by that. For equipment of ship navigation, there are not any particular standards or guidance which Korean users can introduce as considering software functional safety. This article defines the procedure and outcomes of the risk analysis in order to secure software functional safety in marine navigational equipment and applies them to an echo sounder as a case study.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.271-276
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• 2012

This study intented to standardize the method for total polysaccharide, which is a functional marker for aloe vera gel in Korea. We used four lyophilized raw materials and commercial aloe gel products, certified as Health Functional Food by Korea Food and Drug Administration, including powder, solution, jelly, tablet and capsule, to optimize the analytical condition of dialysis and phenol-sulfuric acid reaction in polysaccharide analysis. The optimal conditions for polysaccharide analysis included 1 L water for dialysis and change 3 times for 24hr against 25 mL prepared sample solution. Validation test showed lower than 5% of coefficient of variation(CV) in intra-, interday validation in lyophilized raw materials and 4 types of commercial products. In inter-person and inter-laboratory validation with 4 persons from 4 different laboratories, CV(%) were 5.50 and 6.64 respectively. The linearity of polysaccharide analysis was assessed using 5 serial concentration of lyophilized raw materials(0.1, 0.2, 0.3, 0.4, 0.5%(w/v)). The results showed $R^2{\geq}0.995$ of high linearity. In the commercial aloe vera gel products, the results of reproductivity showed lower than 7.08% and revealed that the standardized method from this study ensured high precision for polysaccharide analysis.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.1051-1065
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• 2020

Safety analysis of nuclear power plant (NPP) especially in accident conditions is a basic and necessary issue for applications and commercialization of reactors. Many previous researches and development works have been conducted. However, most achievements focused on the safety reliability of primary pressure system vessels. Few literatures studied the structural safety of huge concrete structures surrounding primary pressure system, especially for the fourth generation NPP which allows existing of through cracks. In this paper, structural safety reliability of concrete structures of HTR-PM in accidental double-ended break of hot gas ducts was studied by Exceedance Probability Method. It was calculated by Monte Carlo approaches applying numerical simulations by Abaqus. Damage parameters were proposed and used to define the property of concrete, which can perfectly describe the crack state of concrete structures. Calculation results indicated that functional failure determined by deterministic safety analysis was decided by the crack resistance capability of containment buildings, whereas the bearing capacity of concrete structures possess a high safety margin. The failure probability of concrete structures during an accident of double-ended break of hot gas ducts will be 31.18%. Adding the consideration the contingency occurrence probability of the accident, probability of functional failure is sufficiently low.

• Journal of Convergence Society for SMB
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• v.2 no.1
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• pp.11-18
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• 2012

As scale of software has been expanded and complicated, it is difficult to detect hazards which induce functional failure of software. Functional failure of safety-critical system (nuclear power plant, air traffic control systems, railway operating system) could result in a disaster (personal injury, environmental pollution). Therefore, it is necessary to conduct a safety analysis for preventing functional failure and increasing safety of the software. However, there are some reasons (time and effort problem, low knowledge of various safety analysis techniques, selecting conventional technique in company, organization) which disturb selecting an apposite one. This paper presents some traditional safety analysis techniques, recently presented techniques and combined models. We expect that it helps stakeholders to choice adequate one for target system.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.581-585
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• 2017

To strengthen the quality control of aquatic drugs, we compared the internal and external(EU, USA and Japan) aquatic drug classification systems and proposed a new aquatic drug classification system. Aquatic drugs are classified on the basis of their functional the functional characteristics or safety management degree of aquatic drugs. We suggested that the aquatic drugs can be categorized into 7 levels according to their functional characteristics and classified into 3 levels according to the safety management degree of aquatic drugs.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.9
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• pp.1373-1378
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• 2017

This paper presents a basic ECU(Electronic Control Unit) hardware development procedure for the functional safety of in-vehicle network systems. We consider complete hardware redundancy as a safety mechanism for in-vehicle communication network under the assumption of the wired network failure such as disconnection of a CAN bus. An ESC (Electronic Stability Control) system is selected as an item and the required ASIL(Automotive Safety Integrity Level) for this item is assigned by performing the HARA(Hazard Analysis and Risk Assessment). The basic hardware architecture of the ESC system is designed with a microcontroller, passive components, and communication transceivers. The required ASIL for ESC system is shown to be satisfied with the designed safety mechanism by calculation of hardware architecture metrics such as the SPFM(Single Point Fault Metric) and the LFM(Latent Fault Metric).

• Journal of Ocean Engineering and Technology
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• v.24 no.6
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• pp.103-108
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• 2010

WIG crafts are high speed vessels with the features of a dynamic supported craft. These crafts, which are predominantly lightweight and operate at substantially greater speeds than conventional craft, could not be accommodated under traditional maritime safety instruments. WIG crafts inherently possess more hazard factors than conventional ships because of their relatively high speed, lightweight, and navigational characteristics, and an accident is likely to cause damage to the ship and a high loss of life. Because WIG crafts are composed of many systems and subsystems, the safety assessment of a WIG must use a commercial software system in the design stage. This paper reviews a safety assessment process and methodology proposed by the IMO interim guideline, which were developed in view of the configuration of WIG crafts. This safety assessment system was developed to fit the WIG's safety assessment process using a reliability analysis system widely used in commercial systems. The FHA was performed on the functional hazards of systems in the conceptual design stage.

• International Journal of Railway
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• v.1 no.4
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• pp.157-168
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• 2008

The creation of a single European rail transport market it is important to increase confidence between the actors on the market and between member states who shall ensure that railway safety is generally maintained and, where reasonably practicable, continuously improved. For this purpose the European railway safety directive introduces a mechanism to adopt a Common Safety Targets (CST) expressed in risk acceptance criteria for individuals and for society. This paper focuses on the apportionment of safety targets for European railway system. We develop a generic approach based on the Functional Hazard Analysis (FHA), to analyse the safety of railway systems for a unified European network and to comply with the CSTs required by the European railway Safety Directive. We suggest to combine the FHA technique with the functional railway architecture to allocate the safety targets to the railway functions.

• Food Science and Industry
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• v.48 no.4
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• pp.4-10
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• 2015