• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.123-128
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• 2013

The Advanced Power Reactor Plus(APR+), which is a GEN III+ reactor based on the APR1400, is being developed in Korea. In order to enhance the safety of the APR+, a passive auxiliary feedwater system(PAFS) has been adopted in the APR+. The PAFS replaces the conventional active auxiliary feedwater system(AFWS) by introducing a natural driving force mechanism while maintaining the system function of cooling the primary side and removing the decay heat. As the PAFS completely replaces the conventional AFWS, it is required to verify the cooling capacity of PAFS for the core damage frequency(CDF) evaluation. For this reason, this paper discusses the cooling performance of the PAFS during transient accidents. The test case and scenarios were picked from the result of the sensitivity analysis in APR+ Probabilistic Safety Assessment(PSA). The analysis was performed by the best estimate thermal-hydraulic code, RELAP5/.MOD3.3. This study shows that the plant maintains the stable state without the core damages under the given test scenarios. The results of PSA considering this analysis' results shows that the CDF values are decreased. The analysis results can be used for more realistic and accurate performance of a PSA.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.9-17
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• 2017

Ensuring the safety of automobiles and trains during system operation is regarded as indispensable due to the progress in unmanned operation. The automotive functional safety standard, ISO 26262, has been proposed to ensure the safe design of vehicles. This standard describes in detail the required risk analysis and evaluation procedure and safety measures, while appropriately reflecting the system design information. Therefore, much research has been done on the risk analysis procedure, wherein the design information is mostly extracted from physical components of similar systems already in operation, the information traced back to obtain constituent functions, and then methods of identifying risk sources are studied. This method allows the sources of risk to be identified quickly and easily, however if the design requirements are changed or systems are newly developed, others may be introduced which are not accounted for, thereby yielding mismatched design information. To resolve this problem, we propose a top-down analysis in order to utilize the system design information appropriately. Specifically, a conceptual system is designed to obtain the functions, which are then analyzed. Then, a function-based fault tree analysis is conducted, followed by a risk source analysis. In this paper, a case study of automotive safety is presented, revealing that the proposed method can analyze the risk sources with reduced possibility of omission by systematically reflecting the system design information.

• Safety and Health at Work
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• v.6 no.1
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• pp.9-17
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• 2015

The human hand is a complex structure that performs various functions for activities of daily living and occupations. This paper presents a literature review on the methodologies used to evaluate hand functions from a biomechanics standpoint, including anthropometry, kinematics, kinetics, and electromyography (EMG). Anthropometry describes the dimensions and measurements of the hand. Kinematics includes hand movements and the range of motion of finger joints. Kinetics includes hand models for tendon and joint force analysis. EMG is used on hand muscles associated with hand functions and with signal-processing technology.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.241-247
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• 2021

In the article, an analysis of the factors was carried out, which injected into the efficiency of the function of navigation systems in the minds of unimportance. Carrying out analyzes allowing for the visibility of relevant direct adjustments to the effectiveness of the function Inertial navigation systems in the minds of non-value. The designation of the navigation system was assigned to a complex of navigation systems on ships processing of the vector of navigation parameters, so that they can be victorious in the control systems of the ship's collapse, and the safety of floating is safe.

• Proceedings of the Safety Management and Science Conference
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• 2005.05a
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• pp.503-521
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• 2005

Process capability indices are widely used in industries and quality assurance system. When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in considertion of the correlations among the characteristics. To solve the issue on the optimal design for muliple quality characteristics, the study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of terms. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^{++}$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other,

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.69-79
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• 2004

Process capability indices are widely used in industries and quality assurance system. When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in considertion of the correlations among the characteristics. To solve the issue on the optimal design for multiple quality characteristics, the study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of terms. Therefore, the analysis have to be required a multivariate statistical technique. This paper introduces to multivariate capability indices and then selects a multivariate process capability index incorporated both the process variation and the process deviation from target among these indices under the multivariate normal distribution. We propose a new multivariate capability index $MC_{pm}^{++}$ using quality loss function instead of the process variation and this index is compared with the proposed indices when quality characteristics are independent and dependent of each other.

• The KSFM Journal of Fluid Machinery
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• v.5 no.3 s.16
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• pp.25-32
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• 2002

Structural and dynamic analyses of inducer and impeller for an oxidizer turbopump are peformed to investigate the safety level of strength and vibration at a design point. Due to high rotational speed of turbopump, effects of centrifugal forces are carefully considered in the structural analysis. Hydrodynamic pressure is also considered as an external force applied to inducer and impeller blades. A three-dimensional Finite Element Method (FEM) is used for linear and nonlinear structural analyses with modified Newton-Raphson iteration method. After the nonlinear trim solution is obtained from the structural analysis, dynamic characteristics are obtained as a function of rotational speed from the linearized eigenvalue analysis at an equilibrium position. According to the results of numerical analysis, the safety margins of strength and vibration resonances are sufficient enough for safe operation within the requited life cycle.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.271-278
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• 2001

Structural and dynamic analyses of inducer and impeller for a oxidizer turbopump are peformed to investigate the safety level of strength and vibration at design point. Due to high rotational speed of turbopump, effects of centrifugal forces are carefully considered in the structural analysis. Hydrodynamic pressure is also considered as an external force applied to inducer and impeller blades. A three dimensional finite element method(FEM) is used for linear and nonlinear structural analyses with modified Newton-Raphson iteration method. After the nonlinear trim solution is obtained from the structural analysis, dynamic characteristics are obtained as a function of rotational speed from the linearized eigenvalue analysis at an equilibrium position. According to the results of numerical analysis, the safety margins of strength and vibration resonances m sufficient enough to be operated safely within the required life cycle.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.11
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• pp.1526-1532
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• 2014

The Electronic Interlocking unit in railway signalling system is safety-related facilities to determine route and speed for train running. In particular, the SSI(Solid State Interlocking) is Electronic Interlocking unit for high-speed railway, and it performs safety-critical function by MPM(Micro-Processor Module). Meanwhile, MPM is composed of the PES(Programmable Electronic System)-based system, and the PES-based system in railway safety-related facilities should be implemented by complying with the safety requirements defined in IEC 62425 and IEC 61508. In this paper, we performed modeling of failure rate and reliability for MPM implemented by fault tolerance methods and analyzed functional safety for MPM. Moreover, we determined SIL(Safety Integrity Level) for MPM according to the safety requirements defined in IEC 61508 based on an analyzed functional safety.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1363-1368
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• 2008

The extraction and quantitative analysis conditions for astaxanthin from Haematococcus pluvialis, and the structural characteristics of H. pluvialis extract, H. pluvialis hydrolysate and synthetic astaxanthin were investigated using UV/visible and FT-IR spectrometers. Astaxanthin was dissolved in methanol, and then treated to enhance the solubility by sonication for 45 min. With sonication pretreatment, the solubility of astaxanthin increased up to 1.5 times compared to that without sonication. The extracts were hydrolyzed by cholesterol esterase for the analysis of H. pluvialis extract containing astaxanthin ester. A HPLC method using reverse phase C18 column with methanol-water (95:5, v/v) as mobile phase was developed to analyze astaxanthin. After hydrolysis, the absorption spectrum of H. pluvialis hydrolysat was changed to similar pattern to synthetic astaxanthin, confirming the extraction and analysis condition of astaxanthin from H. pluvialis.