• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.195-203
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• 2008

The purpose of this study is to develop a guideline of process capability evaluation and to apply this guideline improving the quality of products, especially in the small and medium enterprises. In this study we deal in the concept of process capability evaluation, the calculation of process capability index, and the application of a case study. Man must compare the state of process with the standards in evaluating of the process capability. Control chart can be used as a yardstick for judgement for the long term period and the distribution shape of histogram for the short term period. Man should regard to the significant figure by the calculation of process capability index.

• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.137-143
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• 2013

The psychiatric patients as subjects were categorized herein into disease- and accident-triggered groups to statistically compare them with each other in terms of various comparative items. At a result, male patients were more dominant than females and physical workers were outnumbered by mental workers in the two groups. Also, patients were more apparent at workplaces with at least 100 employees than the ones with less than 100 employees, and patients whose employment period is at least one year were more vulnerable to stress-related mental disorders than the ones whose employment period falls short of one year. The foregoing findings suggest that there is a need to take preventive measures considering vulnerable aspects in terms of mental disorders.

• Journal of Auto-vehicle Safety Association
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• v.4 no.2
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• pp.17-21
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• 2012

The periodic technical vehicle inspection is to prevent the accident through the finding and fixing the defects of the vehicle. The periodic technical vehicle inspection in Korea was studied for assessing the adequacy of the inspection frequency. The inspection frequencies of many countries including EU, USA and Japan were compared. The average mileages by the vehicle usage and type were represented. The warranty period and recommended replacement period of parts of the domestic auto makers was studied. Currently, the inspection frequency for the periodic technical vehicle inspection in Korea is appropriate. The pass-fail rate and the cost-benefit analysis for the periodic technical inspection in Korea will be needed in the decision making process for the inspection frequency.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.228-233
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• 2001

Satellite system experiences severe mechanical loads during the launch period. Therefore, positive margin of safety of the satellite system must be demonstrated for every possible mechanical loading condition during the launch period. This paper presents modal and stress analysis result due to quasi-static loads for the satellite antenna system. The failure tendency for the sandwich construction of the satellite antenna system has been studied with various lamination angles of unidirectional prepreg.

• Journal of the Korean Society of Safety
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• v.7 no.4
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• pp.45-53
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• 1992

Sponataneous ignition characteristics for granulated activated carbon were observed by performing experiments at constant ambient temperature and varying the ambient temperature sinusoidally. In case of varying the ambient temperature sinusoidally, the amplitudes of temperature were 5$^{\circ}C$, 1$0^{\circ}C$ and 15$^{\circ}C$ respectively, and the period in each amplitude was varied at an interval of 30minutes from zero to 3hours. As the results of experiments at a constant ambient temperature, the critical spontaneous ignition temperature of the sample decreased as the sample vessel size increased. Apparent activation energy of the sample calculated from the Frank-Kamenetskii's thermal Ignition theory was 38.82［kca1/mo1］ In case of varying the ambient temperature sinusoidally, the critical spontaneous ignition tempera-ture was lower than that at the constant ambient temperature, and the minimum critical spontaneous ignition temperature decreased with the amplitude of heating sinusoidal curve. At the same amplitude, the critical spontaneous ignition temperature decreased until it reached the minimum point and then in-creased as the period increased.

• Journal of the Korea Safety Management & Science
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• v.2 no.4
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• pp.209-217
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• 2000

In this paper, we consider an Inventory system with multi-suppliers. A supply agreement is made with one of the suppliers, to deliver a fixed quantity Q evry review period ； That is, adapting to discounts of under the condition of free addition often implies that the timing and sizes of future replenishment orders are less predetermined. The replenishment decisions for the other supplier are governed by a replenishment policy. This paper, multiple suppliers strategy is a combination of a push system (the main supplier delivers every review period a predetermined quantity Q) and a pull system the replenishment orders placed at other suppliers are governed by replenishment policy. The costs are defined as the sum of the ordering, holding, purchasing and opportunity costs. Based on numerical results, conclusions follow about the division of the replenishment volume among the inventory policy.

• Journal of the Korean Society of Safety
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• v.9 no.3
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• pp.74-81
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• 1994

The critical spontaneous ignition temperature for activated carbon were observed by performing experiments for granulated activated carbon with varying the period. As the results of the experiments, the critical spontaneous ignition temperature according to period of 0.5hr, 1.5hr and 2.5hr was 177.5$^{\circ}C$, 176.5$^{\circ}C$ and 172.5$^{\circ}C$ respectively, and the approximate expression of the critical spontaneous ignition temperature obtained for ambient temperature amplitudes was as follow ; $\delta$$_{c}$ (X, $\omega$)=$\delta$$_{c}${1-0.381 exp(-0.930.$\omega$$^{0.811}$)}.

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.305-308
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• 2009

According to the returns of Housing and business cycle over the period 1992 to 2007, it is a measure of the total volatility faced by investors in Housing properties. First, it isn't a distinct difference from business cycle contrary to U.S. Second, the rise of purchase price in total apartments moves up the consumer price index. According to the cross-sectional dispersion of returns and growth in net operating income (NOI) of apartments, industrial, retail and office properties using panel data for U.S. metropolitan areas over the period 1986 to 2002, it is a measure of the total volatility faced by investors in commercial real estate. To the extent that most of that volatility is difficult to diversify, cross-sectional dispersion may be an appropriate measure of risk.

• Proceedings of the Safety Management and Science Conference
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• 2009.04a
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• pp.531-539
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• 2009

The environment of automobile industry in the world is rapidly changing. It is changing of high oil price, technology, environment and construction of competition by newly rising an economic district. Automobile company is focusing on three issue because they want to reinforce competition of automobile industry in the world. That is innovation of production profit management through quality management and Lean. Chance of success is separated in R&D, providing distribution, manufacture, distribution, selling in automobile industry. Emphasis on development process, distribution process, manufacture process, circulation and selling process for strengthening the competitiveness and guarantee. In this thesis, we try to analysis the data set period of automobile production by using survival analysis. While using mean comparison of general statistics commit mistakes, survival analysis can used for including censored data in order to heighten analysis efficiency.

• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.70-78
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• 1997

The objective of this research is to study on the upper and lower layer temperature, interface height and pressure in case of carpet, chair, trashcan and wardrobe fires in a residential room by performing the theoretical and experimental studies. The theoretical results of the upper and lower layer temperature, the interface height and the pressure were qualitatively well coincided with the experimental results. The uniformly distributed fire in case of carpet showed that the ignition and the initial growth period were relatively short while the fully developed period was considerably long. The concentrated fires such as the wardrobe showed that the ignitions and the initial growth periods were relatively long. The interface heights were around 1m as the steady state. However, at the time of the maximum temperature, the interface height was lowered to 0.5m from the floor. The pressure variation in the fire room ranged between 0.1mmAq and 0.4mmAq, and the temperature reached the highest while the pressure was maximum.