• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.87-96
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• 1999

본 연구는 공통의 납기로부터 완성 시간의 편차의 평균제곱을 최소화하는 문제를 비제약적인 경우와 제약적인 경우에 다루고 있다. 모의 뜨임 기법을 이용하여 Eilon과 Chowdhury의 [4] 논문에 있는 예제를 테스트하였다. 제안된 자기 발견적 기법은 대부분의 경우에 좋은 해를 제공하였으며, 작업의 수가 200인 경우에도 해를 1초안에 찾았다. 비제약적인 경우와 제약적인 경우의 계산 결과가 제시되었으며, 다른 자기 발견적 기법에 의한 계산 결과와 비교하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.91-93
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• 2003

자원 제약이 있는 일정 계획 문제는 잘 알려진 NP-hard 문제이다. 이런 문제는 최적해를 구하기 어려운 경우가 많기 때문에 최적해에 근사한 값을 빠른 시간에 구할 수 있는 휴리스틱 방법을 사용한다. 최근에는 휴리스틱의 한가지 방법으로써 유전 알고리즘이 많이 사용되고 있다. 본 논문에서는 자원 제약이 있는 일정 계획문제에 효율적인 유전 연산자를 제안한다. 이 유전 연산자는 자원 제약이 있는 일정 계획 문제에서 기존에 볼 수 없었던 강력한 상속성을 가지고 있다 이 연산자를 표준문제에 적용하여 문헌에 있는 기존의 다른 연산자 보다 우수함을 입증하였다.

• Annual Conference on Human and Language Technology
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• 2020.10a
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• pp.254-256
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• 2020

자연언어처리 문제에서 딥러닝 모델이 좋은 성능을 보이고 있고 딥러닝 결과는 구조화된 결과를 내놓는 경우가 많다. 딥러닝 모델 결과가 구조적인 형태를 가지는 경우 후처리 통해 특정 구조에 맞는 제약을 가해주는 경우가 일반적이다. 본 논문에서는 이러한 제약을 규칙에 기반하지 않고 직접 학습을 통해 얻고자 하였다.

• Journal of the Korean Geographical Society
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• v.30 no.2
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• pp.120-131
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• 1995

To analyze mobility patterns, this study used three Constraint (Capability Constraint, Coupling Constraint, Authority Constraint) models which were proposed in Dr. Hagerstrand's Time-space theory. This paper shows that three constraint models have some effects upon mobility by age. In this study, Capability Constraint means a certain special constraint that is what we can't do during proceeding basic natural urges like sleep, fare, etc. Coupling constraint is a physical one. Each person limits the action range for staying on a special place in special time. For instance, students have to stay in school so that they have mobility constraints. Authority Constraint is a social one. When we use urban facilities or traffic, we may be controlled by mobility sphere by an agreement or a social position. It is social agreement that the opening hour of a store, the time table of mass-transportation and a social positional control that the personal income, the standard of education. In this study it has been in a process of determination of the cluster number that degree of influences a social constraint to mobility. Considering the mobility constraint of characteristics of space divides urban and rural, people in urban area have higher mobility rate than in rural area. Resuets of determination of the cluster, show similar mobility pattern. People in urban area are connected verity of mobility which related to urban space structures with determination of cluste-number. That is to say, mobility patterns can be changed by space charactcristics. Constraints by sex and age are also social constraints and they are influenced by mobility patterns. For instance, females at the age of twenties have similar mobility pattern to the same age male but they have sudden changes after thirty's age. Male entertains a similar pattern without restriction of age. That is to say, management by sex as a social constraint affects mobility. To establish more realistic traffie policy, mobility formation should be reflected to the space in a view of social-behavioral science. To embody this, some problems should be investigated as follows. 1. As a problem of methodology, if sufficient samples ensured, we could subdivide clusters and could open up a new method of analyzing the mobility clusters by using the neuro-network. 2. Extracting actions connected with mobility and finding life cycle which is classified by daily cluste-characteristics, suitable counterproposal could be presented to the traific policy.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.359-366
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• 2010

The purpose of this study is to examine the influence of the leisure constraint of a private security guard on his/her task stress and life satisfaction. The subjects of this study were chosen among the private security guards working in Seoul based private security firms in 2009, and by going through judgement sampling, 300 cases were applied in the final analysis. Collected data went through factor analysis, reliability analysis, regression analysis, and path analysis by using SPSSWIN 17.0. In reference with the reliability of the questionnaire, Cronbach's $\alpha$ was over .600. The conclusion of this study is as following. Firstly, the leisure constraint of a private security guard affects his/her task stress. In other words, when peripheral and individual constraint increase, task stress is intensified, while task stress winds down when interpersonal constraint decreases. Secondly, the leisure constraint of a private security guard affects life satisfaction. That is, when individual constraint goes down, life satisfaction is improved. Thirdly, the task stress of a private security guard affects life satisfaction. when compensation and career development increase, life satisfaction rises. On the other hand when task characteristic is weakened, life satisfaction gets lower. Fourthly, the leisure constraint of a private security guard has a causal influence on task stress and life satisfaction. Accordingly, it becomes apparent that the task stress is a significant variable which intermediates the relation between leisure constraint and life satisfaction.

• Journal of Korea Water Resources Association
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• v.45 no.12
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• pp.1213-1226
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• 2012

Evolutionary algorithms, which are frequently used in an automatic calibration of watershed runoff simulation models, are unconstrained optimization algorithms. An additional method is required to impose constraints on those algorithms. The purpose of the study is to modify the SCE-UA (shuffled complex evolution-University of Arizona) to impose constraints by a penalty function and to improve performance of the automatic calibration module of the SWMM (storm water management model) linked with the SCE-UA. As indicators related to peak flow are important in watershed runoff event simulation, error of peak flow and error of peak flow occurrence time are selected to set up constraints. The automatic calibration module including the constraints was applied to the Milyang Dam Basin and the Guro 1 Pumping Station Basin. The automatic calibration results were compared with the results calibrated by an automatic calibration without the constraints. Error of peak flow and error of peak flow occurrence time were greatly improved and the original objective function value is not highly violated in the automatic calibration including the constraints. The automatic calibration model with constraints was also verified, and the results was excellent. In conclusion, the performance of the automatic calibration module for watershed runoff event simulation was improved by application of the penalty function to impose constraints.

• Journal of Life Science
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• v.31 no.1
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• pp.47-51
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• 2021

In today's society, functional whitening cosmetics are important to beauty. Fungi are known to produce a variety of whitening-related metabolites. In this study, we searched for tyrosinase inhibitors with metabolic products derived from Trichoderma atroviride supernatant in order to apply a material for whitening functional cosmetics. In addition, the inhibitory effect was compared to arbutin, which has already been approved as a whitening raw material by the Korea Ministry of Food and Drug Safety (KMFDS). The metabolites from the T. atroviride supernatant showed higher tyrosinase inhibitory activity than that of arbutin. Some of the tyrosinase inhibitors were stable to heat, whereas some were unstable. The heat unstable material was exhibited in the case of samples treated with little amounts, such as 0.02~0.2%. They were very unstable in acidic and alkali pHs, especially under acidic conditions. However, it was found that a weakly-acidic to neutral pH range was the optimal working pH, especially neutral pH. Since the activity of the inhibitory substances in the T. atroviride supernatant was maintained regardless of proteinase K treatment, it was assumed that the metabolites, but not the bioactive peptides, were involved in the activity. In summary, we propose that the metabolites derived from T. atroviride supernatant have strong potential as whitening raw material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.487-493
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• 2019

This study examines the ratio of R&D expenses in intangible assets for pharmaceutical companies, and determines whether these expenses affect the firm value among companies listed on the KOSDAQ. The research subjects included annual R&D expenses of 39 pharmaceutical companies listed on the KOSDAQ between 2011 and 2017. The survey was achieved via "Panel Data Model" with "Tobin Q" as an independent variable, and the ratio of R&D expenses in intangible as a dependent variable. Results of the study conclude that the ratio of R&D expenses in intangible assets of KOSDAQ pharmaceutical companies negatively influence the Tobin Q (Enterprise Value). A large proportion of intangible assets indicates increased R & D investment, and the operating profit is likely to be low due to the high debt ratio, thereby negatively impacting the enterprise value. This study further investigates whether the existing researches are based on researches that identify the total value of R & D expenditure. Results determine a significant relationship between enterprise value and R & D expenditure.

• Journal of Intelligence and Information Systems
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• v.6 no.2
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• pp.1-14
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• 2000

The berth and crane scheduling problem in a container terminal encompasses the whole process of assigning berth to each ship, determining the duration of berthing, assigning container cranes to each ship, and determining the specific start and end time of each crane service, for all the ships scheduled to be arriving at the terminal during a certain scheduling horizon. This problem is basically a constraint satisfaction problem in which cranes and berths should be assigned in such a way that all the spatial and temporal constraints are satisfied without any interference. However, it is also an optimization problem because the requested arrival and departure time should be met for as many of the scheduled ships as possible, while the operation cost of the terminal should be minimized. In this paper, we present an effective and efficient approach to solving this type of problem, which combines constrain satisfaction search and heuristic repair. We first employ a constraint satisfaction search to find a feasib1e solution. Then, the feasible solution is modified to a more optimal one by iteratively applying our heuristic repair operations within the framework of constraint satisfaction search. Experimental results with a real data from Pusan East Container Terminal showed that our approach can derive a schedule of satisfactory quality in a very short time.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.12
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• pp.615-622
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• 2016

Automotive control software can be a source of critical safety issues when developers do not comply system constraints. However, a violation is difficult to identify in complicated source code if not supported by an automated verification tool. This paper introduces two possible approaches that check whether an automotive control software complies API call constraints to compare their performance and effectiveness. One method statically analyzes the source code and explores all possible execution paths, and the other utilizes a model checker to monitor constraint violations for a given set of constraint automata. We have implemented both approaches and performed a series of experiments showing that the approach with model-checking finds constraint violations more accurately and scales better.