• 대한안전경영과학회지
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• 제10권2호
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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.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.233-235
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• 2003

The voltage and current of fluoescent lamp has been successfully calculated in the case of frequency variation. Energy states of mercury atom in the discharge process are regarded as six levels. These calculations have been accurately solved by numerically employing mixed the FDM and the 2nd Runge-Kutta method. The theoretical calculation results and experimental results were presented to verify the feasibility of the modeling. Calculation and experimental results were presented to verify the feasibility of the calculation.

• 대한안전경영과학회지
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• 제11권1호
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• pp.131-136
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• 2009

The research develops the calculation steps of Z sigma level, process capability index(PCI) and process performance index(PPI) applicable to the discrete process in the service industry. The paper presents three following topics used related process indexes according to the precision and accuray in the continuous process. The contents include diverse process indexs for nonconformities by SPC attribute control charts and bias coefficient. The same technique of the nonconformites is also used in the nonconforming units. The practical examples are provided to help easier understanding for users.

• 한국공작기계학회논문집
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• 제13권5호
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• pp.38-48
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• 2004

Recently the use of high-speed equipment in machine-tool industry has greatly increased, which requires the development of prognostics and prediction methods on the design stage. Conversion of the test/experiments stage from real to virtual reality will not only significantly reduce the design and manufacturing cost, but will also increase design quality. This paper shows how it is possible to develop the automated system for the design calculations of the air-bearing spindles. First, the general calculation method is introduced. It contains several steps, namely, geometry identification, pressure calculation, stiffiness calculation, dynamics characteristics calculation. For geometry identification reducing spindle shaft to rings was proposed, which helps to automate the calculation process. For pressure calculation the Peshti method was implemented. For stiffiness calculation the analysis was made, which shown the necessity of correct calculation step selection. Then the system of ordinary differential equations containing influence coefficients was evolved, which is used for trjectories calculation. The graphical representation of the calculation results shows the dynamic behavior of the spindle unit concerning various working conditions. Finally, this automated system is illustrated by an example of the air-bearing spindle calculation.

• 아태비즈니스연구
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• 제14권2호
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• pp.101-118
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• 2023

Purpose - The purpose of this study is to find out how a company can do reasonable cost calculations in a simple way and establish profitability improvement strategies based on the results. Design/methodology/approach - In this study, a case that compounding company K applied TDABC was studied. A case study was conducted on the process of company K reviewing and applying TDABC and the process of implementing the cost calculation for each product by applying TDABC, and establishing a profitability improvement strategy for each product based on the results. Findings - Company K rearranged the production standard information of the compounding industry such as productivity and batch size of each product to apply TDABC. Cost calculation was performed for each product according to the revised production standard information. After the cost calculation for each product was carried out, Company K established a strategy to improve profitability of each product. The profitability improvement strategy was implemented in two ways: a cost reduction strategy and a product price increase strategy. As a result of the final strategy execution, the profitability of each product was improved. Research implications or Originality - This study found a reasonable costing standard in consideration of the specificity of the research target company, and applied it to cost calculation cost for each product. It contains the process of establishing production and sales strategies for each product based on the cost calculation results. It is expected that this case study will serve as a good reference material for establishing cost calculation and profitability improvement strategies in similar businesses.

• 한국안전학회지
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• 제8권4호
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• pp.165-174
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• 1993

For the safety assessment of the demonstration-scale incineration plant for treating the combustible radioactive wastes, radiation doses of a worker and a residential individual were estimated. The demonstration plant showed a good performance of trial-burn tests using non-radioactive tracers with resulting In high mass reduction of around 40 times and very low emmission of dusts through a stack, which promised a high decontamination factor in an order of 10$^{7}$ . Based on the result s obtained from the trial-burns in the process, the estimation of radiation dose for workers and general publics near the plant was made using dose pathway calculation theories. The parametric values for calculation were selected from design and operational results of the process and from more conservative conditions In reference data. The estimated annual doses for workers and residential indivisuals were 3.07 $\times$ 10$^{-4}$ and 4.35 X 10$^{-8}$ $\mu$Sv/y, respectively, which were high enough to operate the process when comparing with the allowable dose limit in the regulation. The dose calculation models were quite applicable with showing an excellent safety for the process.

• 대한조선학회논문집
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• 제34권1호
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• pp.102-110
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• 1997

현재 조선소에서는 grain stability 계산시에 선박계산 프로그램의 계산 결과치와 실제값 사이의 오차가 크므로 계산 프로그램을 많이 사용하지 않고 있으며, grain stability 계산에 필요한 모든 작업이 수작업을 통해 이루어 지고 있는 실정이다. 본 연구에서는 수작업을 통해 이루어지고 있는 grain stability 계산 작업을 전산화하여 계산작업시간의 단축 및 작업효율성을 극대화할 수 있는 대화형 grain stability 계산 프로그램 그 목적이 있다. 본 연구에서는 사용자의 편의와 대화식 압력 작업을 위해 그래픽 사용자 인터페이스(GUI:Graphical User Interface)를 구현하였고, 3차원 그래픽 라이브러리인 GLBAX를 사용하여 계산에 필요한 형상(girder, hold 형상등)정보들을 가시화하였다. 또한, 선박계산 프로그램과의 접속이 가능하도록 하였다.

• Structural Engineering and Mechanics
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• 제59권5호
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• pp.821-840
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• 2016

A simple design process is proposed for supplemental viscous dampers based on structural safety redundancy. In this process, the safety redundancy of the primary structure without a damper is assessed by the capacity and response spectra. The required damping ratio that should be provided by the supplemental dampers is estimated by taking the structural safety redundancy as a design target. The arrangement of dampers is determined according to the drift distribution obtained by performing pushover analysis. A benchmark model is used to illustrate and verify the validity of this design process. The results show that the structural safety redundancy of the structure provided by the viscous dampers increases to approximately twice that of the structure without a damper and is close to the design target. Compared with the existing design methods, the proposed process can estimate the elastic-plastic response of a structure more easily by using static calculation, and determine the required damping ratio more directly without iterative calculation or graphical process. It can be concluded that the proposed process is simple and effective.

• 한국대기환경학회지
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• 제23권6호
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• pp.752-759
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• 2007

For an accurate measurement of aerosol particle size distribution using a differential mobility analyser (DMA), a new calculation process, capable of predicting the masses for the various kinds of water cluster ions generated from a bipolar ionizer, was prepared by improving the previous process. The masses for the 5 kinds of positive and negative water cluster ions produced from a SMAC ionizer were predicted by the improved calculation process. The aerosol particle charging ratios calculated by applying the predicted ion masses to particle charging equations were in good accordance with the experimentally measured ones, indicating that the improved calculation process are more reasonable than the previous one in a mass prediction of bipolar water cluster ions.

• 산업경영시스템학회지
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• 제31권3호
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• pp.117-124
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• 2008

Ultra-high voltage transformer industry has characteristic of small quantity batch production system by other order processing unlike general mass production systems. In this industry, observance of time deadline is very important in market competitive power security and company continued existence. The transformer winding is a process that rolls a coil is coated with an electric insulation material in order to generate the required voltage using the voltage fluctuation. The winding process is very important production process in the extra-high voltage transformer manufacturing industry because winding process is core process that occupy weight about half of whole process and is process that decide current ratio of transformer. This paper proposes a statistical calculation and control method of planned leadtime on the basis of real data and informations for the A company in transformer winding process. Moreover, we develop unit process scheduling system.