• Journal of Korean Society for Geospatial Information Science
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• v.5 no.2 s.10
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• pp.131-144
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• 1997

Traffic jam densified day by day is phenomenon to occur lack of the road capacity in comparison with traffic density, but lack of the road cannot be concluded by main cause of traffic ism. Because the central function of a city would be concentrated upon the downtown and traffic demand would not be evenly distributed by the classification of an hour. Therefore, this study based on the fact that each driver will select the route generating traffic delay very low when path choice from origin to destination in travel plan estimating the quality of passage could be maintained the speed he want will approach to a characteristic grasp of a road, traffic, driver changing every moment by traffic-demand of road increased as a geometrical series with analysis a classification of a street, a intersection along the path on traffic density and highway capacity analysis the path using GIS techniques about complex street network, also will get the path of actual optimum for traffic delay trend creating under various condition the classification per a hour, a day of week and an incident through network such as analysis for traffic generation zone adjacent about street, intersection, afterward will expect the result increasing efficiency of the road-use through a good distribution of traffic by optimum-path choice, accordingly will prepare the scientific, objective, appropriate basis to decide the reasonable time of a road-widen and expansion through section analysis along a rate of traffic volume vs. road capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.46-54
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• 2018

The Internet of Things (IoT) is an environment in which various devices provide services to users through communications. Because of the nature of the IoT, data are stored and distributed in heterogeneous information systems. In this situation, IoT end applications should be able to access data without having information on where the data are or what the type of storage is. This mechanism is called Service Discovery (SD). However, some problems arise, since the current SD architectures search for data in physical devices. First, turnaround time increases from searching for services based on physical location. Second, there is a need for a data structure to manage devices and services separately. These increase the administrator's service configuration complexity. As a result, the device-oriented SD structure is not suitable to the IoT. Therefore, we propose an SD structure called Name-based Service-centric Service Discovery (NSSD). NSSD provides name-based centralized SD and uses the IoT edge gateway as a cache server to speed up service discovery. Simulation results show that NSSD provides about twice the improvement in average turnaround time, compared to existing domain name system and distributed hash table SD architectures.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.5
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• pp.213-217
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• 2001

Excessive memory buffer requirement in continuous media playback is a serious impediment of wide spread usage of on-line multimedia service. Skewed access frequency of available video files provides an opportunity of re-using the date blocks which has been loaded by one session for later usage. We present novel algorithm which minimizes the buffer requirement in multiple sessions of multimedia playbacks. In continuous media playback originated from the disk, a certain amount of memory buffer is required to synchronize asynchronous disk. Read operation and synchronous playback operation. As aggregate playback bandwodth increases, larger amount of buffer needs to be allocated for this synchronization purpose. The focus of this work is to study the asymptotic behavior of the synchronization buffer requirement and to develop an algorithm coping with this excessive buffer requirement under bandwidth congestioon. We argue that in a large scale continuous media server, it may not be necessary to read the blocks for each session directly from the disk. The beauty of our work lies in the fact that it dynamically adapts to disk utilization of the server and finds the optimal way of servicinh the individual sessions while minimizing the overall buffer space requirement. Optimality of the proposed algorithm is shown by proof. The effectiveness and performance of the proposed scheme is examined via simulation.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.12
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• pp.894-906
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• 2006

There are many difficulties to develop a mobile contents due to many constraints on mobile environments. It is difficult to make a good mobile contents with only visual reduction of existing contents on wire Internet. Therefore, it is essential to devise the data representation and to develop the authoring tool to meet the needs of the mobile contents market. We suggest the compact mobile contents to learn Chinese characters and developed its authoring tool. The animation which our system produces is realistic as if someone writes letters with pen or brush. Moreover, our authoring tool makes a user generate a Chinese character animation easily and rapidly although she or he has not many knowledge in computer graphics, mobile programming or Chinese characters. The method to generate the stroke animation is following: We take basic character shape information represented with several contours from TTF(TrueType Font) and get the information for the stroke segmentation and stroke ordering from simple user input. And then, we decompose whole character shape into some strokes by using polygonal approximation technique. Next, the stroke animation for each stroke is automatically generated by the scan line algorithm ordered by the stroke direction. Finally, the ordered scan lines are compressed into some integers by reducing coordinate redundancy As a result, the stroke animation of our system is even smaller than GIF animation. Our method can be extended to rendering and animation of Hangul or general 2D shape based on vector graphics. We have the plan to find the method to automate the stroke segmentation and ordering without user input.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.5
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• pp.307-313
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• 2011

As production of LCD increases, it has become necessary to find an economically efficient way of treating LCD wastewater with high concentration of fluoride. This study focuses on the calcium sources : $CaCl_2$, $Ca(OH)_2$ and $CaCO_3$ for the treatment of the LCD wastewater including high concentration of fluoride. Of course considering removal efficiency and economical aspect, study is continued. Then this study have objective giving aid to field. Consequently, each calcium source's removal efficiency was measured in various pH, calcium dosage, reaction time, and mixing intensity. The optimum operational conditions for $CaCl_2$ were found to be pH of 7, calcium dosage of 0.4[Ca]/[F] (mol / mol), 1 hr of operation and 200 rpm of mixing intensity. For $Ca(OH)_2$, they were pH of 7, calcium dosage of 30 mL/L, 1 hr of operation, and 200 rpm of mixing intensity. While $CaCO_3$ had operational conditions of pH of 4, calcium dosage of 30 mL/L, 1 hr operation and 200 rpm of mixing intensity. But it is recommended to use calcium sources according to various field conditions.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.4
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• pp.177-183
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• 2016

Sewage treatment using microorganisms is affected by multiple factors such as microbial properties, characteristics of sewage and operating conditions, and nanoparticles inflow may cause negative effects on sewage treatment system especially on the system stability and efficiency. It was studied to assess the toxic effects of nanoparticles on microorganism growth. The activated sludge in the sewage treatment plant of university was cultured in the optimized medium for each strain. Bacillus (gram-positive), Pseudomonas and E.coli (gram-negative) in the activated sludge were selected as target microorganisms, and ZnO and $TiO_2$ were chosen as nanoparticles. For same concentration of nanoparticles, average growth inhibition rate of Bacillus was 60% or more, while that of Pseudomonas was less than 10%. The toxicity of nanoparticles was shown to be higher for gram-positive bacteria than gram-negative bacteria because of their differences on structure of cell wall, components of cell wall protein, physiology of cells and metabolism. ZnO affected 3 times more negative on the growth of microorganisms as compared to $TiO_2$. It was assumed that, therefore, toxicity of ZnO was found to be greater than $TiO_2$.

• Journal of Nutrition and Health
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• v.43 no.3
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• pp.273-284
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• 2010

The purpose of this study was to investigate the effects of weight control program on dietary habits and blood composition in obese middle-aged women. The program consisted of nutrition education, physical exercise and nutrition counseling was conducted for 12 weeks. Participants of the preliminary study were 255 obese women, among which 82 women participated in the nutrition education program. We evaluated the anthropometry, blood lipid profiles, dietary habits of obese women before and after the nutrition education. Dietary habits of the subjects were significantly improved in regularity of having breakfast (p < .05), the frequency of eating snack after dinner (p < .001), eating out (p < .01) and the speed of meal (p < .05) after the program. There was significant decrease in total cholesterol, triglyceride, LDL-cholesterol and systolic pressure of the subjects after nutrition education. Changes of atherogenic index and diastolic pressure were not significant, but had a tendency to decrease. All of the anthropometric outcomes except lean body mass such as BMI, percent body fat, fat mass, and WHR were significantly decreased after weight control program. These findings show that weight control program including nutrition education and counseling can improve dietary habits and weight control pattern, and lead the authors to recommend that public health organizations and dietetic professionals should educate obese women on practical strategies for an effective weight management.

• Proceedings of the Korean Society for the Gifted Conference
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• 2003.11a
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• pp.167-169
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• 2003

과학영재 교육의 목적과 효과를 달성하기 위해서는 과학영재들의 특성, 과학영재의 판별이나 교육 프로그램의 개발, 과학영재들의 과학, 과학자, 과학관련 직업에 대한 인식 등 여러 요소들에 초점을 맞추어 연구해야 하며 이를 바탕으로 교육해야 한다. 과학영재교육의 중요한 점 중 하나는 우리가 교육하는 과학영재들이 성장해서 그들의 영재성을 발휘하도록 하는 것에 있다. 이는 국가적으로도 매우 중요한 일이다. 과학기술의 발달과 국가의 발전은 뛰어난 영재들이 기여를 하였으며 그 업적을 통해 국제경쟁 사회를 선도해 나갈 수 있기 때문이다. 과학영재 교육의 성공 기준 중 하나로 노벨상 수상을 기대하는 것이라고 생각할 수 있다. 물론 노벨상만을 목표로 하는 것은 과학영재교육이 왜곡될 수 있으나, 과학영재교육을 통해서 과학 분야에 뛰어난 인재를 양성하고 이들로부터 과학의 수준이 높아지면서 자연스럽게 노벨상을 수상할 수 있을 것이다. 2002년 노벨 과학상에서 일본은 물리학과 화학 두 분야에서 수상자를 배출하였다. 특히 노벨 화학상을 받은 다나카 고이치는 박사학위도 없는 40대의 평범한 회사원이었다. 그는 일본 과학계를 장악하고 있는 유명 국립대학의 교수도 아니고, 수상 발표 뒤 대부분의 일본 화학자들이 누군지 몰라 당황했을 정도로 잘 알려지지 않은 인물이었다. 이러한 사건은 일본인들에게 희망을 안겨주었으며 과학 및 과학자에 대한 관심과 투자에 대한 인식에 있어 많은 변화를 초래하였다. 노벨상 자체가 국가정책의 목표가 될 수는 없지만, 과학자나 국민 개개인들에게 희망이 되는 것은 사실이다. 해마다 노벨상 수상자가 발표되는 시점에서 우리들은 아주 오랫동안 방관자가 되어 왔다. 이제 여러 과학영재교육기관 등을 통해서 과학영재 교육을 효율적으로 실시한다면 조만간 상황이 바뀔 것으로 기대할 수 있다.택한 이유는 첫 번째가 사회 봉사와 국가 발전에 기여하기 위한 것이었으며, 다음으로는 생활의 안정을 꼽고 있었다. 이외에도 과학적 업적 달성을 위해, 자신의 꿈(이상) 실현을 위해 등의 이유를 들고 있었다. 이러한 경향은 남자 영재와 여자 영재들간에 다소 차이는 있었으나 거의 유사한 것으로 조사되었다(Pearson $X^2$=2.186, p>0.05). 우수한 능력을 소유한 영재들이 과학관련 분야를 선호하지 않는다면 우리나라의 과학 발전은 그리 낙관할 수 없을 것이다. 그러므로, 영재들을 과학 관련 분야로 이끌어 그들이 소유한 영재성을 발휘하도록 하는 것은 매우 중요한 일일 것이다. 이룰 위해서는 과학 영재들이 자신의 능력에 대한 자신감을 더욱 높여야 하며 그 능력을 과학관련 분야에 발휘하도록 하기 위한 국가적, 사회적, 교육적 노력이 필요하다. 노력이 필요하다.~42.1mg$CO_2$/kg.hr였으며 12$^{\circ}C$에서 2.5~8.2mg$CO_2$/kg.hr로 일반적으로 보고되고 있는 토마토 호흡속도와 일치하는 결과를 나타내었다.다.환원당인 sucrose 함량은 계속 증가하였고 fructose, glucose, sorbitol의 함량(추황의 sorbitol을 제외)은 생장이 촉진됨에 따라 증가하다가 다시 점차적으로 감소하였다. 이러한 결과는 총당과 환원당의 측정결과와 일치한 것으로 나타났다. 결론적으로 배의 성장에 따라 산 함량은 감소하였고 당 함량은 증가하였다.luco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.201-209
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• 2004

Important operation parameters and performance of a high temperature ceramic candle filter system were evaluated through a series of demonstration tests at a pilot-scale vitrification plant. At the initial period of each test, due to the growth of dust cake on the surface of ceramic candles, the pressure drop across the filter media increased sharply. After that it became stable to a certain range and varied continuously proportion to the face velocity of off-gas. On the contrary, at the initial period of each test, the permeability of filter element decreased rapidly and then it became stable. Back flushing of the filter system was effective under the back flushing air pressure range of 3∼5 bar. Based on the dust concentrations measured by iso-kinetic dust sampling at the inlet and outlet point of HTF, the dust collection efficiency of HTF evaluated. The result met the designed performance value of 99.9%. During the demonstration tests including a hundred hour long test, no specific failure or problem affecting the performance of HTF system were observed.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.116-123
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• 2000

A numerical model of three-dimensional soil water distribution for drip irrigation management under cropped conditions was developed using Richards equation in Cartesian coordinates. The model accounts for both seasonal and diurnal changes in evaporation and transpiration, and the growth of plant root and the shape of root zone. Solutions were numerically approximated using the Crank-Nicolson implicit finite difference technique on the block-centered grid system and the Gauss-Seidel elimination in tandem. The model was tested under several conditions to allow the flow rates and configurations of drip emitters vary. In general, simulation results agreed well with experimental results and were as follows. The velocity of soil-water flow decreased drastically with distance from the drip source, and the rate of expansion of the wetted zone decreased rapidly during irrigation. The wetting front of wetted zone from a surface drip emitter traveled farther in vertical direction than in horizontal direction. Under this experimental weather condition, water use efficiency of a drip-irrigated apple field was greatest for 4-drip-emitter system buried at 25 cm, resulting from 10% increase in transpiration but 20% reduction in soil evaporation compared to those for surface 1-drip emitter system. Soil moisture retention curve obtained using disk tension infiltrometer showed significant difference from the curve obtained with pressure plate extractor.