• Journal of the Korean Geophysical Society
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• v.4 no.4
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• pp.267-285
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• 2001

This study has tried to develop the modified DRASTIC Model by supplying the parameters,such as structural lineament density and landuse, into conventional DRASTIC medal, and to predict the potential of groundwater contamination using GIS in Whanam 2 Area, Gyeonggi Province, Korea. Since the aquifers in Korea is generally through the joints of rock-mass in hydrogeological environment, lineament denisity affects to the behavior of goundwater and contaminated plumes directly, and land-use reflect the effect of point or non-point source of contamination indirectly. For the statistical analysis, lattice layers of each parameter were generated, and then level of confidence was assessed by analyzing each correlation coefficient. Composite contamination map was achieved as a final result by comparing modified DRASTIC potential and the amount of generation load of several contaminant sources logically. The result could suggest the predictability of the area of contamination potrntial in the respects of hydrogeological aspect and water quality.

• Vending industry
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• v.8 no.3
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• pp.70-79
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• 2008

$\Box$ 시장개요 o 독일 자동판매기 시장은 매출이나 수입, 수출량에서 큰 성장이 없다. 그러나 기존의 주를 이루던 음료, 스낵 자판기 이외에 다양한 자판기 물품 수요가 높아지고 있어 새로운 시장 개척의 기회가 되고 있다. o 자판기 시장의 대부분을 차지하는 음료, 스낵 자판기는 주로 사내에 비치되어 있다. 쉽게 거래처를 바꾸지 않는 독이 바이어 특성상, 기존 고객 유지와 신상품 개발이 주요 성공요인이 될 수 있다. o 자동판매기 시장의 특징은 담당 업체가 자판기 판매에서부터 지속적인 제품 조달 유지, 청소까지 맡게 된다는 점이다. 급격한 수요 증가가 예상되지 않는 한, 구매후의 서비스가 재구매 여부를 결정한다고 할 수 있다. $\Box$ 경쟁 동향 o 독일 자판기 시장에는 독일 제품과 더불어 프랑스, 네덜란드와 같은 주변 유럽국가의 제품들이 시장을 지배하고 있다. 대부분 한 업체에서 물품에 상관없이 다양한 자판기를 생산하고 있다. o 최근에는 선택의 폭이 넓은 복잡하고 다양한 자판기 제품이 인기를 끌고 있다. 박람회를 통해 선보이는 신상품에 대한 관심이 높아지고 있다. o 신선한 디자인과 다양해진 제품의 양이 새로운 구매 요소로 떠오르고 있다. 자판기의 위치 또한 중요한 변수가 되면서 좋은 위치 선점이 경쟁력 향상에 도움이 될 것으로 보인다. $\Box$ 마케팅 참고사항 o 자동판매기의 경우, 사업 파트너와의 협상이나 각각 상품에 따라 가격이 매우 유동적이다. 기존 시장에서의 기업 인지도 역시 가격 협상에 영향을 미치기 때문에 시장의 정확한 가격을 알아보기가 매우 힘들다. 자사의 가격이 곧 핵심역량을 나타내기 때문에 제3자에게 공개되는 일이 적다. o 독일에서는 우리나라와 달리 온라인 광고시장이 활성화되어 있지 않다. 자동판매기도 온라인 광고보다는 전문 잡지를 통해 광고한다. 올해에도 이런 경향은 지속될 것으로 보인다. $\Box$ 수출 시 참고사항 o 자판기 관련 제품의 독일 진출 시 현재까지 특별한 제약 사항은 없다. 관세는 1.7%이며 부가세는 다른 제품과 동일하게 19%를 적용 받는다. o CE 마크의 획득은 필수적이다. 독일 내 진출을 생각한다면 GS 마크를 획득하는 것도 도움이 된다.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.87-94
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• 1999

This study is providing Modified DRASTIC Model to which lineament density and land use are added as additional factors using geographic infomation system(GIS). and then to evaluate groundwater contamination potential of Pyungtek-Gun area in Kyunggi-Do. In this study. the reason for using additional factors is because. in case of lineament density. when we consider that most of aquifer is bedrock aquifer in hydrogeologic environment of the Korea, lineament is very important to flow of groundwater and contamination material. and because land use can reflect indirectly impact of point or non_point source in study area. For statistical analysis. vector coverage per each factor is converted to grid layer and after each correlation coefficient between factors, covariance, variance. eigenvalue and eigenvector by principal component analysis of 3 direction. are calculated. correlation between factors is analyzed. Also after correlation coefficients between general DRASTIC layer and rated lineament density layer and between general DRASTIC layer and rated land use layer are calculated. final modified DRASTIC Model is constructed by using them with each weighting. when modified DRASTIC Model was compared with general DRASTIC Model, comtamination potential in modified DRASTIC Model is fairly detailed and consequently. vulnerable area which has high contamination potential could be presented concretly.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1613-1620
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• 1990

For the purpose of the study on the spray characteristics of a coaxial nozzle, the measurement of the velocity and size of droplets, concentration, and the statistical correlation coefficient between the fluctuation of the velocity and that of the corresponding drop diameter have been carried out. Various method of simultaneous measurement of velocity and drop size have been developed from LDV techniques. The technique used here belongs to the method that supposed by Yule, Holve and Self. It has the advantages of making use of a standard LDV apparatus to which minor modifications have been brought, photomultiplier is equipped with a slit instead of a pinhole and observed the measuring volume at an angle of 90.deg.. The voltage supplied by the photomultiplier has undergone an appropriate analog and digital processing. The experimental results give a good idea of the two phase flow organization and can be helpful to find a drop diffusion model when suitable data are imput.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.7
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• pp.703-714
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• 2010

This paper describes the design optimization of a rotating rectangular channel with staggered arrays of pin-fins by Kriging metamodeling technique. Two non-dimensional variables, the ratio of the height to the diameter of the pin-fins and the ratio of the spacing between the pin-fins to the diameter of the pin-fins are chosen as the design variables. The objective function that is a linear combination of heat transfer and friction loss related terms with a weighting factor is selected for the optimization. To construct the Kriging model, objective function values at 20 training points generated by Latin hypercube sampling are evaluated by a three-dimensional Reynolds-averaged Navier-Stokes (RANS) analysis method with the SST turbulence model. The Kriging model predicts the objective function value that agrees well with the value calculated by the RANS analysis at the optimum point. The objective function is reduced by 11% by the optimization of the channel.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.103-112
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• 1998

A high temperature fabric filter was developed and characterized in order to solve the various problems encountered in the operation of industrial fabric filters. Four kinds of dusts generated in the typical domestic industry were used for its characterization, coke dust from a steel manufacturing process, cement dust from a cement manufacturing process, fly ash from a fluidized-bed combustor, and incinerator ash from a waste plastics incinerator. The physical and chemical properties of the high temperature fabric filter were analyzed in terms of mean flow pore pressure, bubble point pore diameter, mean flow pore diameter, pore size distribution, and the changes in tensile strength and initial elastic modulus under $SO_2$ and $NO_2$ atmospheres. Pressure drop, dust penetration, and figure of merit for the fabric filter were also investigated in a bench-scale filter testing unit. The fabric filter developed in this study had good physical and chemical filter properties and showed a very applicability to typical industrial dusts treatments.

• Journal of the Korean Geographical Society
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• v.39 no.5 s.104
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• pp.755-767
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• 2004

Based on a case study of bank's Automatic Teller Machines (ATMs) in Korea, this paper attempts to reveal dynamic changes occurring across the financial landscape with special emphasis on distribution pattern and location factors. Since the distribution of ATMs showed a concentrated pattern similar to that of bank branches, location quotients were examined to consider the effect of branches on ATM distribution. Furthermore, this study identified four factors that play pivotal roles in the location of ATMs. Compared to branch, location of ATM was more closely related to the population and demand factor, while the importance of local economy base and local economic power factor was reduced to some degree. This difference is attributable to the peculiar characteristic of the services offered by ATM. Lastly, demand factor turned out to be most influential in determining the ratio of ATMs to branches in each district, since lower deployment and operation costs allow ATMs to be more flexibly placed where demand for cash services is high.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1B
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• pp.77-88
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• 2000

This paper presents an approach for rate control by adaptively selecting macroblock modes in video coding.The problem of rate control has been investigated by many authors where quantizer level is adjustedbased on the buffer fullness. The proposed approach is different fron the previous ones [4] id that it finds the optimal decision curve rather than finding a set of the modes. Proposed algorithm extends the coding decision options for rate control to motion/no-motion compensation as well as inter/intra decisions. Instead of having a fixed motion/no-notion compensation or inter/intra decision curve, one can utilize an adaptive decision curvebased on the characteristics of input frames so that the PSNR at a given bit rate is maximized. Therefore, the proposed approach provides better rate control than simple quantizer feedback approach interns of visual quality. The curve is obtained by utilizing simulated annealing optimization technique. Thealgorithm is implemented and simulations are compared with other approaches within H.261 video codec.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.12A
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• pp.1171-1180
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• 2010

In wireless sensor networks, reliable event detection is one of the most important research issues. For the reliable event detection, previous works usually assume the events are only individual objects such as tanks and soldiers. Recently, many researches focus on detection of continuous objects such as wild fire and bio-chemical material, but they merely aim at methods to reduce communication costs. Hence, we propose a reliable continuous object detection scheme. However, it might not be trivial. Unlike individual objects that could be referred as a point, a continuous object is shown in a dynamic two-dimensional diagram since it may cover a wide area and it could dynamically alter its own shape according to physical environments, e.g. geographical conditions, wind, and so on. Hence, the continuous object detection reliability can not be estimated by the indicator for individual objects. This paper newly defines the reliability indicator for continuous object detection and proposes an error recovery mechanism relying on the estimation result from the new indicator.

• Journal of Digital Convergence
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• v.15 no.5
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• pp.61-69
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• 2017

This study aims to investigate the public big data standard analysis model developed by Ministry of the Interior and examine its accuracy and reliability of prediction. To do this, big data standard analysis index were calculated to apply them to the real world case of CCTV monitoring system prior installation in K city. The result of this case study revealed that the areas to be installed CCTV consisted with the area where residences requested and complained to install CCTV monitoring systems, which indicated that the result of big data standard analysis model provided accurate and reliable outcomes. The result of this study suggested implications on effective exploitation of big data analysis.