• ETRI Journal
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• 제35권2호
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• pp.340-343
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• 2013

A novel bumping process using solder bump maker is developed for the maskless low-volume solder on pad (SoP) technology of fine-pitch flip chip bonding. The process includes two main steps: one is the aggregation of powdered solder on the metal pads on a substrate via an increase in temperature, and the other is the reflow of the deposited powder to form a low-volume SoP. Since the surface tension that exists when the solder is below its melting point is the major driving force of the solder deposit, only a small quantity of powdered solder adjacent to the pads can join the aggregation process to obtain a uniform, low-volume SoP array on the substrate, regardless of the pad configurations. Through this process, an SoP array on an organic substrate with a pitch of $130{\mu}m$ is successfully formed.

• Journal of Korean Institute of Industrial Engineers
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• 제22권4호
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• pp.633-649
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• 1996

An interactive multicriteria method, which is called the Modified Pairwise Comparison Stochastic Cutting Plane (MPCSCP) method, is proposed for determining the best levels of the integer decision variables needed to optimize a stochastic computer simulation with multiple response functions. MPCSCP combines good features from interactive tradeoff cutting plane methods and response surface methodologies. The proposed method uses a simple pairwise man-machine interaction and searches an integer space uniformly by using the experimental design which evaluates the decision space centering around an integer center point. The characteristics of the proposed method are investigated through an extensive computational study. The parameter configurations examined in the study are (1) variability of the sampling errors, (2) the size of experimental design, (3) the relaxation of cutting planes, and (4) the levels of decision maker's inconsistency.

• Proceedings of the Technology Innovation Conference
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• 기술경영경제학회 2005년도 제26회 동계학술발표회 논문집
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• pp.109-123
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• 2005

There has been great effect on development and usage of resources as well as technological development including everyday life pattern to maintain environmental sustainability, Also, It is tend to become negative for people's concern of nature ecosystem toward new technological developments because it is neither environmentally, nor naturally friendly. Therefore, our study is to implement expert education and research system which includes the trends and requests of our society with objectives as follows; First, Training industrial technology and policy maker who can understand and practice ecological ethics. Second, Educating people with expertise which can evaluate and complement the environmental friendliness about new industrial technologies. Third, Educating people who can develop technology which is environmentally friendly. Our new program requires various knowledges and balanced point of view. To this end, students are required to understand field of art and sciences including emerging eco-buddhism subject as well as field of state-of-the art environmental technologies such as recycling technology and clean production technology.

• Journal of the Society of Naval Architects of Korea
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• 제28권2호
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• pp.104-117
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• 1991

When a body starts to move, the flow near the intersection point between a body and a free surface changes violently and rapidly in a very short initial time interval. This flow phenomena must be investigated whenever one treats the interaction between a body and a fluid, such as the motion of a floating body, sloshing in a tank, wave maker problem, entry of a body into a fluid etc.. Until Roberts(1987), it was widely accepted that a singularity exists at the intersection point. However, he showed that the singularity does not exist if a body moves non-impulsively. In this paper, an analytical solution cosistent for the case of impulsive motion of a body is obtained by including the effect of surface tension. From the characteristics of the newly obtained solution, a critical value associated with an oscillating phenomenon is found, and further more, it is shown that the oscillating phenomenon does not appear in the region where the distance form the intersection point is less than this critical value.

• Journal of the Korean Institute of Landscape Architecture
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• 제37권6호
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• pp.19-27
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• 2010

The purpose of this study is to evaluate urban parks and green spaces within the public service framework by identifying priority elements. This study surveyed 455 residents from 80 dongs(neighborhoods), of 5 Gu(districts) districts in Daejeon. The results were as follows. Regarding the evaluation of urban parks as a public service, the average survey score, of all 46 questions, was distributed from 2.46 to 3.54(Likert 5 point scale). Interesting findings can be observed in that most of the survey participants gave high scores to Daejon's natural green environments and geographical traits. That is, Daejon residents perceived their urban nature spaces as a natural geographical environment rather than a public service provided by their local government. Therefore, it seems necessary for the local government, by and large, to improve urban parks and urban green space programs. The low scoring items were 'citizen's participation'(mean 2.46), 'acceptance of complaints, comments, and improvement proposals'(mean 2.54), 'citizen's respect', 'inclusive design' (for the physically challenged-mean 2.55), 'diverse programs and activities in the urban park'(mean 2.55) and 'implementation of revision proposals by citizens'(mean 2.61). These results indicate that citizen participation in planning and opinion sharing is needed to build public services that are satisfactory to users. To evaluate the park and green space from the viewpoint of public services is a useful method with a new point of view. In accordance with this study, the factor of 'supply decision maker' is a statistically meaningful variable of resident satisfaction while earlier studies on the satisfaction studies of physical environment, hardly discovered variables on 'supply decision maker', 'acceptance of resident opinions', and 'information usage'. Responding to or taking positive action according to significant factors, such as the findings of this study, can expand the role of public officials to exert a more positive influence on urban parks and green spaces.

• Journal of Environmental Science International
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• 제9권6호
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• pp.443-447
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• 2000

Chonan and Asan city have been a focal point due to rapid development as the first station for Express Railroad and key cities West Coast Development Region. Gokgyo stream adjacent to the cities plays an important role as a drainage channel for an agriculture and a discharger of urban storm water. Waster quality of the stream has been deteriorating caused by pollution sources such as a untreated wastewater discharge and runoff from the watershed. In the study, we conducted 4 surveys in April, May, July, and September to understand the current state of water quality for the stream and to make it possibe to predict future water-quality variation for future development. The system runs on a personal computer under the windows enviroment and provides extensive graphic user interface(GUI) for user-friendly assessment. Using the pull-down menus provided by the GUI panel, the user is able to operate the system by pointing and clicking the icon to identify the state of water-quality at locations concerned. Furthermore, we developed an integrated watershed management system. The constructed system could be a useful tool as a decesion maker for pollution source control strategy.

• Proceedings of the KIEE Conference
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.738-743
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• 1991

A multiobjective analysis technique was applied for the optimum operation of pumps and reservoirs in service water transmission systems. Three major objectives were identified and assessed on the normally operating service water transmission systems. They are, 1) stability of pump operation; 2) economic point of view in minimizing the energy cost for pumping; 3) reliability in meeting the stochasticaly varying demands. The measures of these objectives were required times of pump on-offs in stability, required total energy cost in economics, and minimum required storage during the operating horizon in reliability. In order to find the best meeting solution to the decision maker, a set of non-dominated solutions which show the tradeoff relationships between the considering objectives were generated. The DM selects the best solution from this explicit tradeoff relationships using his heuristic decision rules or experience. The theory was verified by applying to the Kumi Service Water System. A combined technique of the ${\varepsilon}-constraint$ and the weighting methods was used to generate the nondominated solutions, and the dynamic programming algorithm was applied to find the optimal solution for the discretized multi-objective analysis problems.

• Journal of the Korean Operations Research and Management Science Society
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• 제3권1호
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• pp.81-91
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• 1978

Decision models are an attempt to reduce uncertainty in the decision making process. The models describe the relationships of variables and given proper input data generate solutions to managerial problems. These solutions may not be answers to the problems for one of two reasons. First, the data input into the model may not be consistant with the underlying assumptions of the model being used. Frequently parameters are assumed to be deterministic when in fact they are probabilistic in nature. The second failure is that often the decision maker recognizes that the data available are not appropriate for the model being used and begins to collect the required data. By the time these data has been compiled the solution is no longer an answer to the problem. This relates to the timeliness of decision making. The authors point out throught the use of an illustrative problem that stocastic models are well developed and that they do not suffer from any lack of mathematical exactiness. The primary problem is that generally accepted procedures for data generation are historical in nature and not relevant for probabilistic decision models. The authors advocate that management information system designers and accountants must become more familiar with these decision models and the input data required for their effective implementation. This will provide these professionals with the background necessary to generate data in a form that makes it relevant and timely for the decision making process.

• Korean Journal of Human Ecology
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• 제12권1호
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• pp.39-52
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• 2003

This study was conducted to find how to manage the household financial situation and what households demand to financial organization for their satisfaction in Chungbuk Province. The questionnaire survey was implemented from 24th of Oct. for two months and 330 households data among 350 households were analyzed and selected as a sample. The results were as follows : 1. Many households had four to six bankbooks and wives visited financial organs more frequently than their husbands. 2. Although many respondents regarded the safety as the most important point when they selected the financial organ, they were choosing the organ because of the nearness form their own house. 3. How to manage the households' financial situations and how much they were satisfied with the financial organs were different by the respondents' age and education level. 4. The younger they were and the higher the education level was, they managed the household according to the financial plan. Female consumers were more satisfied with financial organs than male did. 5. The financial problem were solved through the couple's communication in many households. This study showed the tendency that the wives' power increasing in the households's decision-making about financial problems.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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• pp.1788-1792
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• 2006

The ordered weighted averaging (OWA) operator by Yager has received more and more attention since its appearance. One key point in the OWA operator is to determine its associated weights. Among numerous methods that have appeared in the literature, we notice the maximum entropy OWA (MEOWA) weights that are determined by taking into account two appealing measures characterizing the OWA weights. Instead of maximizing the entropy in the formulation for determining the MEOWA weights, the new method in the article tries to obtain the OWA weights which are evenly spread out around equal weights as much as possible while strictly satisfying the orness value provided in the program. This consideration leads to the least squared OWA (LSOWA) weighting method in which the program tries to obtain the weights that minimize the sum of deviations from the equal weights since entropy is maximized when the weights are equal. Above all, the LSOWA weights display symmetric allocations of weights on the basis of equal weights. The positive or negative allocations of weights from the median as a basis depend on the magnitude of orness specified. Further interval LSOWA weights are constructed when a decision-maker specifies his or her value of orness in uncertain numerical bounds.