• Parasites, Hosts and Diseases
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• v.33 no.1
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• pp.69-71
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• 1995

From December 1992 to February 1993, all vagrants and children admitted to public welfare facilities supported by the Government of Republic of Korea were examined for the presence of nit, nymph or adult of head louse. Of 36,055 persons examined, the number of positive was 7,393 (20.5%). Intensive control measures are needed to control this ectoparasitic infestation.

• Transactions on Electrical and Electronic Materials
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• v.8 no.2
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• pp.93-96
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• 2007

LCD (liquid crystal display) industry is needed to goods of high reliability and is interested in products without harmful material. In this experiment, we made the LED backlight unit for Automotive-navigation. And for making this backlight unit we used to eight side emitting type white LEDs with 1 W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14 W power consumption and start up voltage time is under the 15ms in the ambient temperature $-20\;^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.8 no.2
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• pp.110-115
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• 1995

This study was devised to observe the inhibitory effects of ethanol treatment precipitate (crude acidic polysaccharide) from Korean red ginseng on a lipolytic action of Toxohormone-L which has been known as lipolytic and anorexigenic factors. Toxohormone-L was obtained by partial purification of the ascites fluid from mice which had been inoculated with sarcoma-180. The yields of crude acidic polysaccharide from Korean red ginseng was 63.5%. In vitro, at the concentration of 500rg /ml, the inhibition rate of lipolysis by the crude acidic polysaccharide of Korean red ginseng was 38.8% and the total inhibitory activity per gram of ginseng material was 4,928 nit. In vivo, the red ginseng polysaccharide(40mg/ml in saline soon.) 16ul/g of body weight was injected to the sarcoma-180 bearing mice once In 3 days until death. The effects against the extension of life span was little but body weight gain of sarcoma-180 bearing mice decreased significantly by administration of Korean red ginseng polysaccharide compared to those of the control group.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.201-204
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• 2001

The tension levelling process is performed to elongate the strip plastically in combination of tensile and bending strain so that all longitudinal fibers in the strip have an approximately equal amount of length and undesirable strip shapes are corrected to the flat shape. This paper is concerned with a simulation of the tension levelling process based on the analysis of the unit model for the tension leveller. Analysis technique such as the sequential analysis of the nit model is suggested and verified with the assembly analysis of the unit model for the effective and economic analysis of the full set of the tension leveller. Analysis of the full tension levelling process using sequential unit models is carried out and provides the effect of the intermesh and optimum amount of the intermesh in tension levelling process.

• Proceedings of the Korea Society for Simulation Conference
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• 2000.04a
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• pp.1-6
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• 2000

현재 무인 운반 차량(AGV: Automated Guide Vehicle)은 자동화된 생산 및 저장 시스템에서 시스템간의 원활한 전달 및 회수를 위한 도구로 중요한 역할을 하고 있다. 하지만 시스템의 규모가 커짐에 따라 기존의 AGV 시스템의 운영 및 통제에 많은 어려움이 발생하게 되었고, 새로운 형태의 AGV 시스템의 설계를 통해 운영의 어려움을 해결하기 위한 연구들이 진행되고 있다. Tandem AGV 시스템, Divided AGV 시스템, SBSL(Segmented Bi-directional Single Loop) AGV 시스템 등이 대표적인 예이다. 이들 시스템들은 기존의 AGV 시스템과는 달리 전체 시스템을 몇 개의 지역으로 나누고, 각 지역에 한 대의 차량을 할당하는 방식으로 차량의 혼잡이나 충돌에 관한 운영의 어려움을 해결하려 하고 있다. 본 연구에서는 이러한 시스템들을 단일루프-단일차량형 AGV 시스템이라 정의하였다. 그리고 Multi-load AGV를 사용하는 단일루프-단일차량형 AGV 시스템을 설계하기 위한 방법론을 제시하고, 시뮬레이션을 통해 nit-load AGV를 사용하는 시스템과의 효율성을 비교, 분석하고자 한다.

• ETRI Journal
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• v.39 no.6
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• pp.782-793
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• 2017

This paper considers the use of the Partial Transmit Sequence (PTS) technique to reduce the Peak-to-Average Power Ratio (PAPR) of an Orthogonal Frequency Division Multiplexing signal in wireless communication systems. Search complexity is very high in the traditional PTS scheme because it involves an extensive random search over all combinations of allowed phase vectors, and it increases exponentially with the number of phase vectors. In this paper, a suboptimal metaheuristic algorithm for phase optimization based on an improved harmony search (IHS) is applied to explore the optimal combination of phase vectors that provides improved performance compared with existing evolutionary algorithms such as the harmony search algorithm and firefly algorithm. IHS enhances the accuracy and convergence rate of the conventional algorithms with very few parameters to adjust. Simulation results show that an improved harmony search-based PTS algorithm can achieve a significant reduction in PAPR using a simple network structure compared with conventional algorithms.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.12
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• pp.77-87
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• 1993

PMOSFETs were studied on the effect of Hot-Carrier induced drain leakage current (Gate-Induced-Drain-Leakage). The result turned out that change in Vgl(drain voltage where 1pA/$\mu$m of drain leadage current flows) was largest in the Channel-Hot-Hole(CHH) injection condition and next was in dynamic stress and was smallest in electron trapping (Igmax) condition under various stress conditions. It was analyzed that if electron trapping occurrs in the overlap region of gate and drain(G/D), it reduces GIDL current due to increment of flat-band voltage(Vfb) and if CHH is injected, interface states(Nit) were generated and it increases GIDL current due to band-to-defect-tunneling(BTDT). Especially, under dynamic stress it was confirmed that increase in GIDL current will be high when electron injection was small and CHH injection was large. Therefore as applying to real circuit, low drain voltage GIDL(BTDT) was enhaced as large as CHH Region under various operating voltage, and it will affect the reliablity of the circuit.

• Vacuum Magazine
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• v.3 no.3
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• pp.19-23
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• 2016

BNNTs (Boron nitride nanotubes) is an analogue of CNTs (Carbon Nanotubes) in terms of lattice structure. In BNNTs, a boron atom forms sp2 hybridized bonding with three nitrogen atoms, and so does a nitrogen with three boron atoms in the honeycomb structure. Its innovative properties, such as high thermal conductivity, neutron shielding capability, superb oxidation resistance at $900^{\circ}C$, excellent chemical resistance, and superior mechanical properties are advantageous for a wide range of applications, especially for electric device packages, neutron shielding, protective coating materials, and functional composites. In this paper, boron nitride nanotube synthesis, properties and application are reviewed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.12B
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• pp.1498-1505
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• 2009

In centralized control sensor network, tree-based multi-channel communication overcomes the recurrent channel switching and makes possible to transfer data simultaneously from different sources. In our paper, we propose a greedy algorithm named as NIT (Non-Intersecting Tree) that the trees can avoid inter-tree interference. We also propose channel switching technique by which trees can avoid link failure or area blocking due to external interference locally without rerunningthe algorithm and without interrupting the whole network. At first we applied our algorithm for a random topology and then we evaluate the performance of the network using NS-2 simulator. The results show that with the increasing of channel the throughputand delivery ratio are increased significantly. We got better performance than a using a recent proposed Tree-based Multi-Channel Protocol (TMCP).

• Advances in robotics research
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• v.1 no.1
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• pp.21-39
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• 2014

Due to the rapid progress in the field of robotics, it is a high time to concentrate on the development of a robot that can manoeuvre in all type of landscapes, ascend and descend stairs and sloping surfaces autonomously. This paper presents details of a prototype robot which can navigate in very rough terrain, ascend and descend staircase as well as sloping surface and cross ditches. The robot is made up of six differentially steered wheels and some passive mechanism, making it suitable to cross long ditches and landscape undulation. Static stability of the developed robot have been carried out analytically and navigation capability of the robot is observed through simulation in different environment, separately. Description of embedded system of the robot has also been presented and experimental validation has been made along with some details on obstacle avoidance. Finally the limitations of the robot have been explored with their possible reasons.