• Journal of Distribution Research
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• v.1 no.2
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• pp.221-251
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• 1996

The retail industry of Korea has, owing to the increase of purchasing power of her people and the changing pattern of consumption appetite, marked a considerable development. Nevertheless the retail industry of Korea is still in primitive stage with its smallness of size, density of stores and inefficiency of management compared to those in the developed countries. It is a high time for Korean distribution market to boost its competitive power in the wake of the opening of distribution industry since January of 1996. Accordingly, it should be the goal of these markets to maximize its positive aspects while trying their best to minimize the negative aspect in this transition time for globalization.

• Journal of Distribution Science
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• v.3 no.1
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• pp.1-22
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• 2005

국내 유통산업의 외형적 성장에 비하여 유통이론에 관한 연구가 균형을 이루지 못하고, 유통이론에 대한 체계적인 접근이나 연구방법, 대상 등에 대한 연구가 시행되지 않은 상황에서 본고에서 지금까지 단편적으로, 그리고 지엽적으로 연구된 유통이론에 대하여 다각적인 방면에서의 논의와 정립의 필요성을 느끼게 된 바, 윤명길 외(2004) 이어 본 연구는 국내 실정에 맞는 유통이론을 학문적으로 정립을 위하여 유통의 계보와, 연구 대상, 연구방법에 대한 유통이론(론) 차원의 접근을 시도하고자 하였으며, 그 연구 방법을 제안하였다. 연구가 국내 유통이론 정립에 기여하기를 바라는 마음에서 시작되지만, 부족한 부분이 있다는 것은 두말할 필요가 없을 것이다. 작은 바람이 있다면, 유통 이론 분야에 많은 연구자들의 참여를 통하여 진전된 연구가 되기를 바라며, 유통이론의 유입국에서 유출국으로 기대를 가져본다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.1
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• pp.111-117
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• 2007

This paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic Algorithm (GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transforming problem to minimize load generated load point outage in each sub-section. This approach is one of the most difficult procedures and become combination problems. A new approach using GA was developed for this problem. GA is a general purpose optimization technique based on principles inspired from the biological evolution using metaphors of mechanisms such as natural selection, genetic recombination and survival of the fittest. Test results for the model system with 24 nodes 29 branches are reported in the paper.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.67-73
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• 2010

The temperature distribution of diesel particulate filter with five partitioned electric heaters is numerically analyzed to investigate the condition of regenerating ceramic filter. The commercial code STAR-$CCM+^{(R)}$ is utilized to simulate multi-dimensional steady hot air flow in DPF. In order to verify the computational results, thermocouples are used to measure the temperature distribution in DPF. Computational results agree well with experimental ones. The results show that the maximum temperature in DPF is lowered as the mass flow rate of exhaust gas increases, which means that the more power in heater will be necessary as the engine speed increases. Compared with heater placed at center, heater at circumference has the higher maximum temperature in DPF. The maldistribution of flow field in front of heater has the main influence on the temperature distribution in DPF.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9A
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• pp.1306-1313
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• 1999

In this paper, we propose the signal strength path loss model (modified Hata path loss Model) and the signal strength distribution model (log-normal distribution) for the cell design of the land mobile communication system. We applied the measured experimental data at Soosungdon and Sanjuckdong in Daeku, to this model and calculate the fraction of total area above threshold.

• Journal of radiological science and technology
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• v.21 no.2
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• pp.43-46
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• 1998

When a patient was irradiated with prosthetic hip, the dose distribution was changed according to inhomogeneous materials. The density, effective atomic number, and the composition of material had influence on absorbed dose distribution. In this study, the influence of inhomogeneous material(Ti) was measured using a polyethylene phantom, which consisted of various diameter of titanium, with film dosimetry. As a result, the backward dose showed 29.5% increas by backscattering, the forward dose showed 28% decreas by absorption, and the side dose showed 7% increas by scattering, when 25 mm diameter Ti was used. In addition forward dose was in inverse proportion to the thickness of prosthetic material. When the prosthetic hip of patient is in an irradiated field, we must carefully study the absorbed dose distribution.

• Journal of environmental and Sanitary engineering
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• v.24 no.3
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• pp.55-61
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• 2009

Fe-V is used as raw material of vanadium in the steel making process. The purpose of this study, Fe-V is to replace the $VO_{4}$. So the distribution behavior of vanadium in $VO_{4}$ of the steel investigated. The distribution ratio of the vanadium where potential of the free oxygen ion will increase in slag decreased. When CaO and MgO content which is a basic oxide from CaO-$SiO_2$-FetO-MgOsatd. slag increases, S distribution ratio increases. CaO-$SiO_2$-FetO-MgOsatd. slag better than CaO-$SiO_2$-$Al_2O_3$-MgO slag is the recovery of vanadum and desulfurization.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.2
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• pp.153-168
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• 2016

Sloshing phenomenon is a complicated free surface flow problem that increases the dynamic pressure on the sidewalls and the bottom of the storage tanks. When the storage tanks are partially filled, it is essential to be able to evaluate the fluid dynamic loads on the tank's perimeter. In this paper, a numerical code was developed to determine the pressure distribution on the rectangular and trapezoidal storage tanks' perimeters due to liquid sloshing phenomenon. Assuming the fluid to be inviscid, the Laplace equation and the nonlinear free surface boundary conditions were solved using coupled boundary element - finite element method. The code performance for sloshing modeling was validated using Nakayama and Washizu's results. Finally, this code was used for partially filled rectangular and trapezoidal storage tanks and free surface displacement, pressure distribution and horizontal and vertical forces exerted on the tanks' perimeters due to liquid sloshing phenomenon were estimated and discussed.

• Journal of Welding and Joining
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• v.27 no.2
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• pp.57-62
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• 2009

This research was carried out to improve the productivity in the subassembly process of shipbuilding through optimal work planning for the shortest work time. The work time consist of welding time, moving time of gantry, teaching time of robot and robot motion time. The shortest work time is accomplished by even distribution of work and the shortest welding sequence. Even distribution of work was done by appling the simple algorithm. The shortest work sequence was determined by using GA. The optimal work planning decreased the total work time of the subassembly process by 4.1%. The result showed the effectiveness of the suggested simple algorithm for even distribution of work and GA for the shortest welding sequence.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.3
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• pp.302-308
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• 2014

In this paper, a detailed investigation of the random vibration test is presented for strapdown inertial navigation systems (INS). The effect of the random vibration test has been studied from the point of view of navigation performance. The role of distribution functions and RMS value is represented to determine a feasible method to reject or reduce vibration related error in position and velocity estimation in inertial navigation. According to a survey conducted by the authors, this is the first time that the effect of the distribution function in vibration related error has been investigated in random vibration testing of INS. Recorded data of navigation grade INS is used in offline static navigation to examine the effect of different characteristics of random vibration tests on navigation error.