• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.7
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• pp.1141-1148
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• 1997

In the stamping industry the blank shape to be stamped into a designed shape has been conventionally determined from the try out process by the press engineers. The work needs a lot of time and thus leads a loss of productivity. In this study boundary element method for 2-dimensional potential problem was used to design optimum blank shapes for irregular press forming. Here we assumed that the blank is controlled by blank holder only and material flow at blank holder was under potential flow. The developed PC code for designing the optimum blank shape shows that the blank shapes for optimal drawing can be calculated within a few minute in pentium PC and the calculated shapes agree well with the experiments. However the application of this method is constrained only to the pressed product with flat bottom.

• The Journal of Fisheries Business Administration
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• v.38 no.1 s.73
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• pp.19-45
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• 2007

There have not been many studies which considered both quantitative and qualitative location factors on the issues of site selection problems for a fish farm. This study develops AHP(analytic hierarchy process) model to resolve site selection problem for a fish raising farm by using quantitative and qualitative factors. In order to evaluate the validity of the location factors found in the literature review, the study used advice from fish raising farmers and related academic experts. Four major factors have been selected as economic factors, social factors, natural environmental factors and infrastructures. An AHP structural diagram has developed by considering the factors and potential sites proposed for fish farming. Through the survey on the preference of factors and potential sites, pairwise comparison matrices have been estimated and used to calculated the relative weights of each potential site. The AHP model process shown in the study can be applied to resolve site selection problems for fish raising farmers.

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.26-33
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• 1998

It has been referred as a problem that heat source/sink is distance from heat demand area in using unused energy. To solve the distance problem in using unused energy, the water from city water system like tap water, rain water, waste water used as unused energy. To survey the potential of the water of city water system, it is developed that the calculation method of the potential using unit method. The amount of theoretical unused energy and energy saving in the Osaka City, Japan were estimated by using that method.

• Journal of Environmental Science International
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• v.15 no.5
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• pp.493-501
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• 2006

The increase in environmental loads and energy consumptions has resulted in the need of developed new forms of energy for a sustainable use for the society. Recently, the viability of using unused energy has attracted a great deal of attention. From the view point of using unused energy, the most critical problem can be referred to as the distance between the heat source/sink and heat demand area. The water resource in the city water system was used to solve this distance problem with unused energy. The calculation method of the potential use unit was used to survey the potential of the water resource in the city water system. The amount of theoretical unused energy and energy savings in the model city were estimated using this method. It is estimated that the amounts of energy savings and $CO_2$ reduction correspond to 131.3 GWh and 29280[t-C], respectively, per annual basis.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.313-320
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• 2009

Indonesian Ministry of Environment estimates that each year 170 cities and regencies in Indonesia produce 45,764,354.30 $m^3$ or approximately 11,441,091.08 ton of solid waste. Unfortunately, unsustainable management system has created a severe waste problem, hazardous to health and environment. This paper deals with the problem and offers some solutions. They are 3R (Reduce Reuse and Recycle), waste-to-energy concept and landfill gas (LFG) utilization. While 3R policy has been adopted by the government, the remaining two technologies are still dormant. Thus the paper provides a complete yet compact analysis of technology, economics, and environment aspect of waste-to-energy and LFG. Given the facts of waste production and management in Indonesia, the purpose is to encourage Government of Indonesia and other stake holders (including international community) to explore and exploit this potential. Potential of reducing waste negative externality while receiving extra revenue. Two bird with a stone.

• International Journal of Internet, Broadcasting and Communication
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• v.6 no.1
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• pp.5-8
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• 2014

Social networking services that connect a person to other people are attracting our attention and various types of on-the-network services are provided. Library has been playing a role of social media by providing with materials such as books and magazines, and with a place for reading, studying, getting lectures, etc. In this paper, we present a method for finding candidates of groups of the library's patrons who share interest areas by utilizing the loan records, which are obtainable by every library. Such a homogeneous group can become a candidate for a study group, a community for exchange ideas, and other activity group. We apply the method to a collection of loan records of a university library, find some problem to be solved, and propose measures for more detailed solutions. Even though the potential group finding problem still remains a lot of problems to be solved, its potential importance is very high and thus to be studies even more for future applications.

• International journal of advanced smart convergence
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• v.13 no.1
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• pp.1-11
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• 2024

Cognitive small cell networks, consisting of macro-cells and small cells, are foreseen as a promising candidate solution to address 5G spectrum scarcity. Recently, many technological issues (such as spectrum sensing, spectrum sharing) related to cognitive small cell networks have been studied, but the common control channel (CCC) establishment problem has been ignored. CCC is an indispensable medium for control message exchange that could have a huge significant on transmitter-receiver handshake, channel access negotiation, topology change, and routing information updates, etc. Therefore, establishing CCC in cognitive small cell networks is a challenging problem. In this paper, we propose a potential game theory-based approach for CCC establishment in cognitive radio networks. We design a utility function and demonstrate that it is an exact potential game with a pure Nash equilibrium. To maintain the common control channel list (CCL), we develop a CCC update algorithm. The simulation results demonstrate that the proposed approach has good convergence. On the other hand, it exhibits good delay and overhead of all networks.

• Journal of Educational Research in Mathematics
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• v.27 no.1
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• pp.51-67
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• 2017

Analogical reasoning is a mathematically useful way of thinking. By analogy reasoning, students can improve problem solving, inductive reasoning, heuristic methods and creativity. The purpose of this study is to analyze the analogical reasoning of preservice mathematics teachers while constructing quadratic curves defined by eccentricity. To do this, we produced tasks and 28 preservice mathematics teachers solved. The result findings are as follows. First, students could not solve a target problem because of the absence of the mathematical knowledge of the base problem. Second, although student could solve a base problem, students could not solve a target problem because of the absence of the mathematical knowledge of the target problem which corresponded the mathematical knowledge of the base problem. Third, the various solutions of the base problem helped the students solve the target problem. Fourth, students used an algebraic method to construct a quadratic curve. Fifth, the analysis method and potential similarity helped the students solve the target problem.

• 대한공업교육학회지
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• v.33 no.2
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• pp.120-136
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• 2008

Using the tangible programming tools, which combines physical objects (e.g. robot) and educational programming language, may help to encourage learners' creative thinking as well as to enhance problem solving ability. That is, learners can have opportunities to simulate problem solving processes through the physical objects, such as robots. Therefore, they can minimize an fixation about problem solving process. These experience is effective to induce creative thinking that is useful to find new solutions and change environment actively. Therefore, we developed a robot based programming teaching and learning curriculum and implemented it in college level introductory programming courses. The result shows that the robot based programming learning has a positive effect in all three factors of learners' creative problem solving potential, especially in a cognitive factor. The cognitive factor includes general problem solving abilities as well as factors that explain creativity, such as divergent thinking, problem recognition, problem representation. These result means that the developed robot based programming teaching and learning curriculum give positive effect to creative problem solving abilities.

• Structural Engineering and Mechanics
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• v.4 no.2
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• pp.191-202
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• 1996

This paper presents a construction of adaptive boundary element for the problem with mixed boundary conditions such as heat transfer between heated body surface and surrounding medium. The scheme is based on the sample point error analysis and on the extended error indicator, proposed earlier by the authors for the potential and elastostatic problems, and extended successfully to multidomain and thermoelastic analyses. Since the field variable is connected with its derivative on the boundary, their errors are also interconnected by the specified condition. The extended error indicator on each boundary element is modified to meet with the situation. Two numerical examples are shown to indicate the differences due to the prescribed boundary conditions.