• 전기전자학회논문지
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• 제13권3호
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• pp.24-31
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• 2009

The computation time of FEA(finite element analysis) for one model may range from a few seconds up to several hours according to the complexity of the simulated model. If these FEA is used to calculate the objective and the constraint functions during the optimal solution search, it causes very excessive execution time. To resolve this problem, the distributed computing technique using internet web service is proposed in this paper. And the dynamic load balancing mechanisms are established to advance the performance of distributed computing. To verify its validity, this method is applied to a traditional mathematical optimization problem. And the proposed FEA-based optimization using internet distributed computing is applied to the optimal design of the permanent magnet dc motor(PMDCM) for automotive application.

• 한국CDE학회논문집
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• 제4권4호
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• pp.285-294
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• 1999

This paper presents a content-search system built on distributed environments using the open product model of STEP, The content-search system searches design data for given product descriptions such as part name and features. Distribute object interfaces has been defined by IDL and distributed product data are searched through CORBA protocols. Web interfaces are also provided for interactive user interfaces. Given a user request, a mediator interacts with distributed search servers and sends collected results back to the user. The mediator has such metadata as location, program name, and other information about product data stored on distributed system. The search servers use SDAI interfaces to search STEP files or databases. The content-search system promotes the reuse of previous design within a company and the outsourcing of part designs.

• 대한전기학회논문지:전력기술부문A
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• 제54권11호
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• pp.518-524
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• 2005

This paper presents an analytical method for the reliability evaluation of distribution system, including the distributed generations. Unlike the large sized generations of transmission system, the distributed generations have complexities in analyzing and determining the operation. In the process of evaluate reliability, it can be shown that the analytical method is simpler than the Monte-Carlo simulation and the method using Load Duration Curve model is more accurate than that using peak load model. The modeling of distributed generation to analysis distribution system reliability using LDC is proposed in this Paper, and is compared with the MCS method as a result of case studies.

• 융합보안논문지
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• 제12권6호
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• pp.51-59
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• 2012

본 논문에서 제안하는 학습몰입모형 "BoX" 는 B-Boy들이 대회에서 우승하기 위해 분산인지(distributed cognition) 경쟁을 능동적으로 즐기는 문화에서 그 발상의 기초를 두고 있다. "Battle"은 경쟁을 의미하며 X는 본 연구에서 제안하려는 교수법 적용과목이다. 본 논문의 목적은 학습자가 높은 수준의 학습몰입 상태에서 창조적 문제해결능력을 배양하는 학습모형을 제시하는 것이다. "BoX" 구현의 핵심은 개인인지부하를 줄이는 분산인지 활동을 극대화하도록 학습자간의 경쟁질서와 통제원리를 설계하는 것이다. 두 학기의 IT교육과정에서 비교학생군의 학습 성취도를 분석한 결과, "BoX" 학습모형이 기존의 수업방식에 비해서 학습몰입도와 학습 성취도를 크게 높이는 것을 확인하였다.

• 한국지리정보학회지
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• 제15권3호
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• pp.103-118
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• 2012

분포형 모형은 유역내에서 공간 분포된 임의 지점의 유출해석 결과를 손쉽게 얻을 수 있다. 이때 다양한 특성을 가지는 소유역으로 구성된 유역의 경우, 소유역에 대해 신뢰성 있는 유출량을 얻기 위해서는 소유역별로 보정된 모형을 적용해야 한다. 본 연구에서는 관측 유량자료가 있는 소유역별로 모형을 보정할 수 있는 다지점 보정 기술을 개발하였다. 이를 위해서 다지점 보정 대상매개변수의 선정 및 적용 방법과 소유역 네트워크 정보를 설정하는 방법을 제시하였다. 또한 다지점 보정 모듈을 구현하기 위한 클래스를 설계하고 GUI를 개발하였으며, 소유역별로 설정된 매개 변수를 이용한 유출해석 절차를 정립하였다. 다지점 보정 모듈을 낙동강 수계 선산 유역($977km^2$)에 적용하였다. 적용결과 다지점 보정 모듈은 유역내 소유역에 대한 모형의 보정에 효과적으로 적용할 수 있었으며, 다지점 보정에 의해서 소유역의 유출해석 결과를 향상시킬 수 있었다.

• 한국식품영양학회지
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• 제7권4호
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• pp.399-405
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• 1994

Some method was introduced to explain oxygen transfer from broth to cell during aerobic microbe cultivation. It is explained by 5 steps that how desolved oxygen can reach to cell. Among these steps film resistance was the most important factor to describe oxygen transfer. Lumped model and distributed model was introduced to explain oxygen diffusion rate and oxygen consumption rate which occurs in the microbe pellet.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.51-60
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• 2003

The growth of the World Wide Web and the advances in high-speed network access have greatly changed existing CAD/CAE environment. The WWW has enabled us to share various distributed product data and to collaborate in the design process. An international standard for the product model data, STEP, and a standard for the distributed object technology, CORBA, are very important technological components for the interoperability in the advanced design and manufacturing environment. These two technologies provide background for the sharing of product data and the integration of applications on the network. This paper describes a distributed CAD/CAE environment that is integrated on the network by CORBA and product model data standard STEP. Several prototype application modules were implemented to verify the proposed concept and the test result is discussed. Finite element analysis server are further distributed into several frontal servers for the implementation of distributed parallel solution of finite element system equations. Distributed computation of analysis server is also implemented by using CORBA for the generalization of the proposed method.

• 한국물환경학회지
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• 제26권2호
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• pp.252-260
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• 2010

The point rainfall measurements need to be converted to the areal rainfall by means of mean areal precipitation (MAP) estimation methods. And it is not appropriate to evaluate the areal rainfall with constant drift because of the geomorphological influences to rainfall field. Non-stationarity should be applied to the estimation of the areal rainfall, therefore, to consider these effects. Kriging methods with special functional would be a suitable tool in this case. Generalized covariance Kriging method is the most developed one among different Kriging methods. From this point of view this study performs the analysis of its applicability to distributed runoff model. For these purpose, distributed rainfall was created by Thiessen and Kriging method. And distributed rainfall of each method was applied into HyGIS-GRM. The result of applying, Runoff was different in the rainfall data form. Therefore, To apply Kriging method with physical meaning is that it is the useful method as distributed rainfall-runoff model.

• 조명전기설비학회논문지
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• 제19권8호
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• pp.70-76
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• 2005

본 논문은 분산전원이 연계된 배전계통의 신뢰도를 평가할 수 있는 해석적 기법과 그에 맞는 분산전원의 모델을 제시한다. 분산전원은 송전계통에 연계된 대규모 발전기와는 다른 운영방식을 가지기 때문에 기존의 기법과는 다른 해석기법과 모델을 필요로 한다. 제시되는 신뢰도 해석기법은 Monte-Carlo 시뮬레이션에 비해 간단하면서도 피크부하를 사용하는 해석기법에 비해 정확하기 위해 Load Duration Curve를 사용하였고, 최종적으로는 사례연구를 통해 제시된 기법의 정확성을 입증하였다.

• KIEE International Transactions on Power Engineering
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• 제4A권3호
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• pp.122-128
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• 2004

With the advent of distributed generation, power systems are fundamentally impacted in regards to stability and power quality. Distributed generation has a positive impact on system restoration following a fault, higher reliability, and mitigation of effect due to voltage sag. However, distributed generation also has a negative impact on decrease of reliability such as changes of protective device setting and mal-operation. Because bulk power systems consist of various sources and loads, it becomes complicated to analyze a power system with distributed generation. The types of distributed generation are usually classified by both rotating machinery and the inverter-based system. In this paper, distributed generation is designed by rotating machinery, and the distributed system having a model of the distributed generation is simulated using EMTP. In addition, this paper presents the simulation results according to the types of distributed generation.