• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.881-887
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• 2005

A total knee replacement is an extremely 'position-sensitive' operation; a malposition or a malalignment of the components will lead to a breakage of the component, a fracture around the knee prosthesis, and the limitation of range of the motion, etc. In a conventional total knee replacement, surgeons have to select an appropriate prosthesis according to the shape of the surgical region. A wrong selection may give rise to side effects or to need re-operation. Nevertheless, it is so difficult to choose the most proper prosthesis out of various kinds of prosthesis. This paper presents a surgical planning system for the total knee replacement with an operation simulating method in order to determine the parameters for the total knee replacement operation. We select an alignment axis and a resection angle as major operation parameters in the total knee replacement operation, and introduce the method to determine the major operation parameters with the operation simulator we developed. The simulator is used to determine operation parameters for optimized operations, to select the most appropriate prosthesis, and to analyze the prospective problems of the operation.

• 대한전기학회논문지
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• 제43권2호
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• pp.251-258
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• 1994

To apply the Power MOSFET to the high powerd circuits, the parallel operation of the Power MOSFET must be considered because of their low power rating. This means, in practical applications, design methods for the parallel operations are required. However, it is very difficult to investigate the problem of parallel operations by directly changing the internal parameters of the MOSFET. Thus, in this paper, the effects of internal parameters for the parallel operation are investigated using SPICE program which is often used and known that the program is very reliable. The investigation results show that while the gate resistance and gate capacitances are the parameters which affect to the dynamic switching operations, the drain and source resistances are the parameters which affect to the steady-state current unbalances. Through this investigation, the design methods for the parallel operation of the MOSFET are suggested, which, in turn, contributes to the practical use of Power MOSFETs.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권9호
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• pp.694-705
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• 2010

진화 프로그래밍은 실수형 최적화 문제에 널리 사용되는 알고리즘으로 돌연변이 연산이 중요한 연산이다. 일반적으로 돌연변이 연산은 확률 분포와 이에 따른 매개변수를 사용하여 변수값을 변화시키는데, 이 때 매개변수 역시 돌연변이 연산의 대상이 됨으로 이를 위한 또 다른 매개변수가 필요하다. 그러나 최적의 매개변수 값은 주어진 문제에 전적으로 의존하기 때문에 매개변수 개수가 많은 경우 매개변수값들에 대한 최적 조합을 찾기 어렵다. 이러한 문제를 부분적으로나마 해결하기 위하여 본 논문에서는 변수의 돌연변이 연산을 위한 매개변수를 자기 적응적 관점에서 이론적으로 추정한 돌연변이 연산을 제안하였다. 제안한 알고리즘에서는 코시 확률 분포의 축척 매개변수를 추정하여 돌연변이 연산에 적용함으로 축척 매개변수에 대한 돌연변이 연산이 필요하지 않다는 장점이 있다. 제안한 알고리즘을 벤치마킹 문제에 적용한 실험 결과를 통해 볼 때, 최적값 측면에서는 제안한 알고리즘의 상대적 우수성은 벤치마킹 문제에 의존하였으나 계산 시간 측면에서는 모든 벤치마킹 문제에 대하여 제안한 알고리즘이 우수하였다.

• 한국전기전자재료학회논문지
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• 제22권6호
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• pp.537-545
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• 2009

In this paper, new parameters were developed to estimate the depth of anesthesia during a general anesthesia using EEG. Power spectral density(PSD) analysis was used for these parameters because EEG became slow wave during anesthesia. The new parameters were DTR, ATR, TDR, ADR, BTR and BDR applied to PSD. These parameters were compared with SEF which is conventionally used at clinic and confirmed clinical value. As the results, DTR, ATR, TDR, ADR among parameters were not useful compared with SEF but BTR and BDR is valuable for clinic. 15 patents, at pre-operation BDR the value is $265.36{\pm}25.29$, at induction the value is $129.23{\pm}34.92$, at operation the value is $154.99{\pm}38.34$, at awaked the value is $283.83{\pm}39.80$ and at post-operation the value is $234.80{\pm}23.46$. Also at pre-operation BTR value is $183.38{\pm}13.59$, at induction the value is $104.09{\pm}25.11$, at operation the value is $115.38{\pm}23.42$, at awaked the value is $190.33{\pm}23.31$ and at post-operation the value is $172.38{\pm}19.08$. Trend of BDR and BTR is similar to change of SEF, so two parameters are useful. to estimate the depth of anesthesia.

• 조명전기설비학회논문지
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• 제25권4호
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• pp.71-78
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• 2011

This paper contains the selection of operation parameters for protection and control of steam turbine in a Korea Standard Type Nuclear Power Plant. The safety of nuclear reactor must be ensured which generates nuclear energy and produces steam. Also, the safety of turbine, which consume the nuclear energy as a core machine, must be ensured. For the purpose of this, we describe how the operating parameters were selected, reviewed, implemented into the operator console and finally put into actual operation of the system.

• 대한교통학회지
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• 제14권1호
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• pp.69-80
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• 1996

In most cities, travel demand is distributed along long corridors and its destinations tend to concentrate in a central business district. For this kind of many-to-one or one-to-many travel demand pattern, a zonal operation of buses can be an efficient bus operation technique in which a long bus-demand corridor is divided into service zones and each service zone is provided with its own bus route connecting the service zone and single destination separately. This paper develops models of the total transportation costs for a single-zone operation and 2-zonal operation of buses for a long demand corridor with single destination in terms of various cost parameters, demand density, bus operation speeds, and location of the boundary between two service zones. In this study the total transportation cost is assumed to consist of the bus operation cost, passenger waiting cost and passenger travel time cost. It was proved that a zonal operation of buses can be more efficient than a single-zone operation for certain circumstances of the system and an boundary condition between two operation techniques was obtained. Also, several case studies were performed for various values of the cost parameters.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2008년도 추계학술대회
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• pp.421-427
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• 2008

In manufacturing industry, cutting parameters have an influence on reducing the production cost and time and deciding the quality of a final product However, owing to governmental regulations and the change of owner's cognizance, the machining safety becomes important in those fields relatively. The paper presents an intelligent operation planning system considering machining safety for milling operations. The main issue of the system is to determine the cutting parameters in achieving a balanced consideration of productivity and worker's safety. The detailed algorithm and functions of the developed system is introduced and then discussed.

• 한국안전학회지
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• 제21권6호
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• pp.116-121
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• 2006

절삭가공에서 가공조건은 가공비용의 감소와 제품 품질의 향상에 영향을 주는 주요 요인 중의 하나이다. 일반적으로 공정설계자는 제품의 목표 품질을 만족하는 범위 내에서 비용을 줄일 수 있는 가공조건을 결정하기 위하여, 가공조건 핸드북 등에서 제공하는 표준 가공조건을 세부 공정별 요구 사항이 만족되도록 경험을 기반으로 수정한 후 작업자의 안전에 문제가 없는 지 검토한다. 본 논문에서는 공정설계자의 경험에 의해 수행되는 일련의 과정을 신경회로망 모델과 규칙에 의해 모델링한 작업설계시스템을 소개한다. 개발된 시스템은 각주형 부품의 밀링 작업에서 (1) 표준 가공조건을 세부 공정별 요구 사항이 만족되도록 신경회로망 모텔에 의해 수정하고, (2) 다음으로 작업자의 안전을 만족하도록 수정된 가공 조건을 필터링하는 모듈로 구성된다. 본 논문에서는 우선 개발된 밀링 작업설계시스템의 전반적인 기능을 간략히 소개한 후, 제안된 방법론에 의한 의사결정 과정을 자세히 기술한다. 마 지막으로 실제 적용 예를 통하여 개발된 시스템의 성능을 예시하도록 한다.

• 한국환경과학회지
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• 제11권1호
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• pp.63-68
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• 2002

In this study, we examined statistical analysis between sewage plant operations parameters and effluent quality We got six components from principle component analysis of the operation parameters and secondary effluent quality. 91.8% of the total variance was explained by the six components. The components were identified in the following order : 1) organic matter removal by aeration basin microbe, 2) settleability on secondary clarifier load, 3) removal of nutrients, 4) microbial number increasement and species diversity, 5) microbial activity in aeration basin, 6) oxidation in aeration basin.

• Journal of Mechanical Science and Technology
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• 제15권1호
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• pp.81-87
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• 2001

Cyclic variability limits the range of operating conditions of spark ignition engines, especially under lean and highly diluted operation conditions. The cyclic combustion variations can be characterized by pressure parameters, combustion related parameters, and flame-front related parameters. The coefficient of variation (COV) in indicated mean effective pressure (IMEP) defines the cyclic variability in indicated work per cycle.