• Proceedings of the Safety Management and Science Conference
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• 2000.11a
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• pp.203-216
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• 2000

In this paper, we Investigate rationales for feedback adjustment using some techniques associated with automatic process control based on some nonstatioary disturbance models. Feedback-control schemes are often operated so that the nature of the disturbance that is being compensated is concealed and unusual deviations from the target cannot be taken account of. In this connection feedback control schemes is useful to extend the idea of common causes and special causes to such systems. Minimum-cost feedback schemes are discussed for some simple ,but practically interesting ,models.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.905-906
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.883-884
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• 2005

• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.271-276
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• 2004

The risk assessment model is an important subsystem for effective establishment and operation of EMS (environment management system). In case of poor risk assessment long-term and large-scale failure expense might be brought. Managing policy, target and other indices based on risk assessment can guarantee successful EMS. In this paper, we aim at comparative analysis of various risk methods and propose an alternative risk assessment model for EMS.

• Proceedings of the Safety Management and Science Conference
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• 2004.11a
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• pp.453-457
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• 2004

EPC seeks to minimize variability by transferring the output variable to a related process input(controllable) variable. In the case of product control, a very reasonable objective is to try to minimize the variance of the output deviations from the target or set point. We consider an alternative EPC model with first-order autoregressive disturbance.

• Proceedings of the Safety Management and Science Conference
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• 2003.05a
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• pp.195-201
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• 2003

This study investigated the management environment of medium and small business by examining the role of medium and small business in national economics, the change in management condition, and the problems in Qualify and technique. Also we analyzed problems in the past quality control activity of our medium and small business, and examined the driving direction and introduction method of QM. And to understand the effect of manager's concern in quality management to observe the quality system before and after introduction of QM. A target for this investigation is the medium and small business which has introduced QM through ISO 9000.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.33-42
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• 2012

This paper dealt with developing conceptual model for making public policy on consumer product safety. The matters of consumer safety, public health and environmental protection are essential parts of making policy for consumer products. Moreover, policy authority should consider all measures based on consumer safety. In the process making regulations, policy authority has to have some methods to prevent errors on treating eligible persons as persons disqualified under uncertainty decision making of public policy. To recognize and ensure fairness on public policy, policy authority needs to establish basic policy making and fundamental concepts. Therefore, we developed conceptual model for consumer products safety, CPSPcon in this paper. The conceptual model is one part of SSM(Soft System Methodology) and can support specific policy target. The CPSPcon model can assist in evaluation of responses to an adapting or considering model.

• Journal of Applied Reliability
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• v.10 no.2
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• pp.107-122
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• 2010

Functional safety is the part of the overall safety of a system that depends on the system or equipment operating correctly in response to its inputs, including the safe management of likely operator errors, hardware failures, systematic failures, and environmental changes. One of the essential concepts of functional safety is Safety Integrity Level(SIL). It is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction. In this paper, each element of SIL assessment will be defined. Based on each element, specific process of SIL selection will be established by using flowchart. The flowchart provides a SIL assessment guideline for functional safety engineers. The proposed theory will be verified by applying to a oil refining plant for SIL assessment.

• Geomechanics and Engineering
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• v.6 no.2
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• pp.99-115
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• 2014

Uncertainties in design variables and design equations have a significant impact on the safety of geotechnical structures like retaining walls and slopes. This paper presents a possible framework for obtaining the partial safety factors based on reliability approach for different random variables affecting the stability of a reinforced concrete cantilever retaining wall and a slope under static loading conditions. Reliability analysis is carried out by Mean First Order Second Moment Method, Point Estimate Method, Monte Carlo Simulation and Response Surface Methodology. A target reliability index ${\beta}$ = 3 is set and partial safety factors for each random variable are calculated based on different coefficient of variations of the random variables. The study shows that although deterministic analysis reveals a safety factor greater than 1.5 which is considered to be safe in conventional approach, reliability analysis indicates quite high failure probability due to variation of soil properties. The results also reveal that a higher factor of safety is required for internal friction angle ${\varphi}$, while almost negligible values of safety factors are required for soil unit weight ${\gamma}$ in case of cantilever retaining wall and soil unit weight ${\gamma}$ and cohesion c in case of slope. Importance of partial safety factors is shown by analyzing two simple geotechnical structures. However, it can be applied for any complex system to achieve economization.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.195-196
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• 2012

Because of the high level of the safety and durability, a lot of reinforcing bars is placed in the concrete structure of the Nuclear Power Plant. But the overcrowding re-bars cause some problems during the construction as the diseconomy, construction delay, quality deterioration, and so on. These problems can be solved by applying the high-strength reinforcing bars to NPP structure. To achieve this, after analysing the structural target performance like the control of cracks, adherence, shear, torsion, development of reinforcement and earthquake-resistance, the results of the analysis will be reflected in the structural performance evaluation test.