• 경영과학
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• 제18권1호
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• pp.135-145
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• 2001

In recent environment of dynamic management, there is growing recognition that information and knowledge management systems are essential for efficient/effective decision making by CEO. To cope with this situation, we suggest the Data-Miming scheme as a key component of integrated information and knowledge management system. The proposed system measures business performance by considering both VA(Value-Added), which represents stakeholder’s point of view and EVA (Economic Value-Added), which represents shareholder’s point of view. To mine the new information & Knowledge discovery, we applied the improved genetic algorithms that consider predictability, understandability (lucidity) and reasonability factors simultaneously, we use a linear combination model for GAs learning structure. Although this model’s predictability will be more decreased than non-linear model, this model can increase the knowledge’s understandability that is meaning of induced values. Moreover, we introduce a random variable scheme based on normal distribution for initial chromosomes in GAs, so we can expect to increase the knowledge’s reasonability that is degree of expert’s acceptability. the random variable scheme based on normal distribution uses statistical correlation/determination coefficient that is calculated with training data. To demonstrate the performance of the system, we conducted a case study using financial data of Korean automobile industry over 16 years from 1981 to 1996, which is taken from database of KISFAS (Korea Investors Services Financial Analysis System).

• 한국전자통신학회논문지
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• 제5권4호
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• pp.471-479
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• 2010

홀로노믹 구동 기술은 임의의 방향으로 회전 운동과 병진운동을 동시에 구현 할 수 있다. 이런 이유로 홀로노믹 구동 기술은 모바일 플랫폼의 모션을 만드는데 있어 가치가 있으며, 특히 장애물 있기 쉬운 환경에서 모바일 시스템을 작동의 경우, 조종 가능성이 중요한 문제로 부각되는 로봇과 자동차 분야의 이동 어플리케이션으로써 많은 이점을 가진다. 이 논문에서 다수의 서보 캐스터를 이용하여 홀로노믹 구동 시스템을 구현하는 현실적인 방법에 대해 소개한다. 홀로노믹 동작 구현은 다른 서보-캐스터 동작의 조화를 통해 각각의 서보-캐스터의 구동과 조향을 조절한다. 또한 이 논문에서 작동 상황 요구에 따라 조작방법이 달라지는 알고리즘을 제안한다.

• 산업공학
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• 제12권4호
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• pp.551-556
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• 1999

In this paper, we compare the performance of three data mining classification algorithms(neural network, decision tree, logistic regression) in consideration of various characteristics of categorical input and output data. $2^{4-1}$. 3 fractional factorial design is used to simulate the comparison situation where factors used are (1) the categorical ratio of input variables, (2) the complexity of functional relationship between the output and input variables, (3) the size of randomness in the relationship, (4) the categorical ratio of an output variable, and (5) the classification algorithm. Experimental study results indicate the following: decision tree performs better than the others when the relationship between output and input variables is simple while logistic regression is better when the other way is around; and neural network appears a better choice than the others when the randomness in the relationship is relatively large. We also use Taguchi design to improve the practicality of our study results by letting the relationship between the output and input variables as a noise factor. As a result, the classification accuracy of neural network and decision tree turns out to be higher than that of logistic regression, when the categorical proportion of the output variable is even.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.477-480
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• 1996

The main objective of this research is to develop the optimal control method for a Distribution Center - multi Branch inventory distribution system. With the continuous review policy, the distribution center places an order for specific order quantity to an outside supplier, and the order quantity is replenished after a certain lead time. Also, each branch places an order for particular order quantity to the distribution center to satisfy the customer demands, and receives the replenishment after a lead time. When an out of stock condition occurs during an order cycle, a backorder is placed to the upper level to fill the unfilled demands. With these situation, variable demand and variable lead time are used for better industrial practice. Futher, actual lead times with a generic lead time distribution are used in developing the control model. Under the actual lead time model, the customer service measures actually attained for the distribution center and each branch are explained as the effective customer service measures. Thus, throughout the optimal control (using computer search procedures), we can set the desired service levels for the distribution center and each branch to produce the effective service level for each branch which is consistent with the goal level of service for each branch. At the same time, the entire distribution system keeps minimum inventories.

• 정신신체의학
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• 제9권1호
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• pp.66-80
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• 2001

인생을 살아가는 동안 누구든지 스트레스를 경험한다. 심리사회적 스트레스 요인은 매우 다양하다. 또한 그에 대한 개인의 스트레스평가, 대응, 반응들도 매우 다양하다. 여기에는 개인차가 많이 있는데, 개인적 자원이나 취약성 인자와 같은 개인적 소인의 영향을 받기 때문이다. 이러한 스트레스과정의 결과로서, 개인은 정신적 성장의 기회가 되거나, 정신적, 신체적 적응(안녕)에 변화가 없을 수도 있으며, 또는 부적응(질병) 상태를 초래할 수 있다. 따라서 개인에게 맞는 스트레스 예방관리나 치료법이 필요하다. 진료의사가 임상현장에서 스트레스 관련 환자들을 진료할 때 스트레스의 전반적인(특히 심리사회적) 이해가 필수적이다. 저자는 그러한 이해를 돕기 위해서 심리사회적 측면의 스트레스와 관련된 문헌들을 포괄적으로 고찰하였다.

• Communications for Statistical Applications and Methods
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• 제25권2호
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• pp.173-184
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• 2018

In medical or public health research, it is common to encounter clustered or longitudinal count data that exhibit excess zeros. For example, health care utilization data often have a multi-modal distribution with excess zeroes as well as a multilevel structure where patients are nested within physicians and hospitals. To analyze this type of data, zero-inflated count models with mixed effects have been developed where a count response variable is assumed to be distributed as a mixture of a Poisson or negative binomial and a distribution with a point mass of zeros that include random effects. However, no study has considered a situation where data are also censored due to the finite nature of the observation period or follow-up. In this paper, we present a weighted version of zero-inflated Poisson model with random effects accounting for variable individual follow-up times. We suggested two different types of weight function. The performance of the proposed model is evaluated and compared to a standard zero-inflated mixed model through simulation studies. This approach is then applied to Medicaid data analysis.

• 대한안전경영과학회지
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• 제3권3호
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• pp.55-64
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• 2001

The main objective of this research is to develop a model to select the optimal input service level for a distribution center-multi branch inventory distribution system. With the continuous review policy, the distribution center places an order for specific order quantity to an outside supplier, and the order quantity is replenished after a certain lead time Also, each branch places an order for particular order quantity to the distribution center to satisfy the customer demands, and receives the replenishment after a lead time. When an out of stock condition occurs during an order cycle, a backorder is placed to the upper level to fill the unfilled demands. With these situation, variable demand and variable lead time are used for better industrial practice. Further, actual lead times with a generic lead time distribution are used in developing the control model. Under the actual lead time model, the customer service measures actually attained for the distribution center and each branch are explained as the effective customer service measures. Thus, throughout the optimal control (using computer search procedures), we can select the optimal input service levels for the distribution center and each branch to attain the effective service levels for each branch which is consistent with the goal level of service for each branch. At the same time, the entire distribution system keeps minimum inventories.

• 한국화재소방학회논문지
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• 제24권5호
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• pp.10-25
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• 2010

현대사회에서 재난의 잠재력이 커질수록 재난을 대비하고 대응하는 국가의 체계를 보다 효율적으로 개선하고 강화하기 위하여 재난관리담당부서에서 근무하는 공무원을 대상으로 설문을 받아 분석하였다. 이 연구에서 알아보고자 한 내용은 다음과 같다. 첫째, 재난관리 기관 간 협력관계, 둘째, 재난관련법 제정 및 재난전담부서의 필요성 셋째, 재난관리 상황적 변수에 대한 인식으로 재난관리 상황요인에 대한 전반적 인식, 재난유형에 대한 전반적 인식, 재난규모에 따른 발생가능성에 대한 인식, 넷째, 재난관리의 구조적 변수에 대한 인식으로 재난관리에 대한 소방방재청, 유관기관, 지방자치단체의 인식 차이, 예방-대비-대응-복구단계의 혼선에 대한 인식에 대한 연구이다.

• 태양에너지
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• 제17권1호
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• pp.35-46
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• 1997

In this study comparison of experiment results with the computed results of linear theory and nonlinear theory using singularity method was obtainable. Specially singularity points like sources and vortexes on hydrofoil and freestreamline were distributed to analyze two dimensional flow field of supercavitating cascade using nonlinear theory, and governing equations of flow field were derived and hydraulic characteristics of cascade were calculated by numerical analysis of the governing equations. The results compared linear theory and nonlinear theory with the experiment results of the study are as follows: The tolerances of nonlinear theory were larger than those of linear theory in case of ${\alpha}<10^{\circ}$. Moreover the computational range of attack angles could be expanded from ${\alpha}=10^{\circ}$ to ${\alpha}=25^{\circ}$, the flow field of supercavitating cascade could be analyzed in the condition which the wake thickness and the length of cavity are a variable. The shapes of cavity were changed sensitively according to various variable such as attack angles, pitches and wake thickness, and the pressure distribution of hydrofoil surface was identical almost disregarding wake thickness but changed largely according to attack angle and the length of cavity. Lift coefficient and drag coefficient were reduced according to increasing of wake thickness but the influences of wake thickness were very little in the situation of small pitch and long cavity.

• 한국도서관정보학회지
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• 제42권3호
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• pp.351-379
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• 2011

도서관의 저작물 복제 전송 보상금제도는 2003년에 도입되었고, 2004년 7월부터 도서관에서 실시되어 7년 이상이 경과되었다. 본 연구는 도서관의 저작물 복제 전송 보상금제도의 운영현황을 조사하였고, 보상금제도의 효율성을 저자집단과 사서집단을 대상으로 설문조사를 실시하였다. 먼저 저자집단과 사서집단 간의 보상금제도 효용성의 차이를 분석하였다. 또한 저자집단의 신분변수에 따른 보상금제도 효용성의 차이를 분석하였고, 사서집단의 신분변수에 따른 보상금제도 효용성의 차이 등을 분석하였다. 끝으로 분석 결과 도출된 문제점을 지적하고 이를 해결하기 위한 개선방향을 제시하였다.