• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2711-2718
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• 2012

The alkylation of the ambident enolates of a methyl glycinate Schiff base with ethyl chloride was studied at B3LYP and MP2 levels with $6-31+G^*$ basis set. The free (E)-enolates and (Z)-enolate are similar in energy and geometry. The transition states for the alkylation of the free (E)/(Z)-enolate with ethyl chloride have similar energy barriers of ~13 kcal/mol. However, with a lithium ion, the (E)-enolate behaves as an ambident enolate and makes a cyclic lithium-complex in bidentate pattern which is more stable by 11-23 kcal/mol than the (Z)-enolate-lithium complexes. And the TS for the alkylation of (E)-enolate-lithium complex coordinated with one methyl ether is lower in energy than those from (Z)-enolate-lithium complexes by 4.3-7.3 kcal/mol. Further solvation model (SCRF-CPCM) and reaction coordinate (IRC) were studied. This theoretical study suggests that the alkylation of ambident enolates proceeds with stable cyclic bidentate complexes in the presence of metal ion and solvent.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.7
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• pp.779-784
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• 2005

This paper presents the theory of similarity transformations applied to the momentum and energy equations for laminar, forced, external boundary layer flow over a horizontal flat plate which leads to a set of non-linear, ordinary differential equations of phase change material slurry(PCM Slurry). The momentum and energy equation set numerically to obtain the non-dimensional velocity and temperature profiles in a laminar boundary layer are solved. The heat transfer characteristics of PCM slurry was numerically investigated with similar method. It is clarified that the similar solution method of Newtonian fluid can be used reasonably this type of PCM slurry which has low concentration. The data of local wall heat flux and convective heat transfer coefficient of PCM slurry are higher than those of water more than 150$\~$200$\%$, approximately.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.3
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• pp.53-62
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• 1994

Complex decision-making problems are often characterized by multicriteria phenomena and fuzziness inherent in the structure of information and therefore suitable scientific solution methods. Especially, when similar dependent criteria are introduced, the problems become more complex. This paper presents a fuzzy intersectional dependence relation model for this kind of multicriteria decision-making problems. The model we propose is based on the fuzzy relation from fuzzy systems theory. In ths case of introducing similar dependent criteria, the rank reversal by distortion of weights is hard to occur by our proposed method. A numerical example is presented to illustrate the use of the model.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.11
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• pp.890-898
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• 2000

본 논문에서는 단순 다각형을 대상으로 하는 형태 변환 알고리즘을 제안한다. 주어진 다각형을 삼각 분할하고 그 듀얼 트리로부터 구성된 듀얼 루트 트리를 이용하여 형태 변환을 유도하는 기하학적인 방법이다. 이 방법은 기존의 알고리즘이 수학적인 모델링을 기반으로 하기 때문에 감수해야했던 많은 양의 함수계산을 피할 수 있으며 다각형의 속성을 유지하는 삼각 분할을 사용함으로써 중간 단계에 생성된 다각형들이 언제나 적합한 형태의 다각형이 될 수 있다는 특징을 갖는다. 이러한 작업이 가능하도록 하기 위해서 본 논문에서는 유사 삼각 분할(similar triangulation)과 유사 트리의 개념을 이용하였다.

• 전기의세계
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• v.13 no.3
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• pp.38-41
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• 1964

This thesis is aimed to obtain efficiently economically any desired phases and single phase transformer without unbalance by using only a new transformer, applying the theory of rotating magnetic field. The brief construction and principle is as floow: two pieces of similar ring cores, triangular cores or polygonal cores are located on the upper and lower sides with equidistance. And the some number of similar leg cores, shaped a square-pillar or a sylinder, are arranged at equidistant of the core section. Ring windings or polyphase windings of AC machines are adopted as a winding method on the upper and lower cores. Three phase AC is applied to the primary windings on these cores so that the rotating magnetic field is induced on the cores and this magnetic fluxes pass through each of the secondary windings on the leg-cores with some difference in time.

• Journal of Information Technology Applications and Management
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• v.12 no.1
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• pp.141-155
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• 2005

It is very important that sellers provide reasonable reserve prices for auction items in internet auction systems. Recently, an agent has been proposed to generate reserve prices automatically based on the case similarity of information retrieval theory and the moving average of time series analysis. However, one problem of the previous approaches is that the recent trend of auction prices is not well reflected on the generated reserve prices, because it simply provides the bid price of the most similar item or an average price of some similar items using the past auction data. In this paper. in order to overcome the problem. we propose a method that generates reserve prices based on the moving average. the exponential smoothing, and the least square of time series analysis. Through performance experiments. we show that the successful bid rate of the new method can be increased by preventing sellers from making unreasonable reserve prices compared with the previous methods.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.697-701
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• 2012

Numerical modeling for a coke dry quenching process was developed and evaluated. The cokes had similar characteristics to a porous material, therefore, its quenching analysis was simplified as a cooling process of porous blocks. A uniform inlet temperature and constant properties of materials in the oven were also assumed. With given operating conditions, temperature profiles in the cokes were calculated and compared to the actual values. The calculated temperature gradient was high at the upper part of the coke flow and the cooling rate decreased as cokes came down to the exit port. The exit port temperature of cokes was similar to the measured value, however, temperature-dependent material properties and operating conditions must be considered to predict the temperature precisely. The calculated results could be applied to design a coke oven to produce high quality cokes.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.182-187
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• 2000

In this paper, we have proposed a new approach to the design of robot vision system to develop the technology for the automatic test and assembling of precision mechanical and electronic parts for the factory automation. In order to perform real time implementation of the automatic assembling tasks in the complex processes, we have developed an intelligent control algorithm based-on neural networks control theory to enhance the precise motion control. Implementing of the automatic test tasks has been performed by the real-time vision algorithm based-on TMS320C31 DSPs. It distinguishes correctly the difference between the acceptable and unacceptable defective item through pattern recognition of parts by the developed vision algorithm. Finally, the performance of proposed robot vision system has been illustrated by experiment for the similar model of fifth cell among the twelve cell for similar model of fifth cell among the twelve cell for automatic test and assemblig in S company.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.353-358
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• 2002

The purpose of this paper was to estimate the cumulative damage of pavement concrete by split tension fatigue test. The split tension fatigue test of variable amplitude loading were performed in two and three stages. The results of the fatigue test by variable amplitude loading showed that the sums of damage were greater than 1 in the increasing sequence loading tests, and less than 1 in the decreasing sequence loading tests. The remaining life estimated by equivalent damage theory was almost similar to that of experimental results.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.151-154
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• 2000

Standard of implementing a robot is Man, so in many field, Many studies are processing to archive a robot, very similar to human being. This paper, based on the theory of man, implemented on the model of parallelism sense and visual information, which is needed when it's moving. Introduced robot uses CCD and designed Image Processing Board for the purpose of archiving vision data. To keep parallel condition, This use ultrasonic sensors for auto-mobile.