• Tribology and Lubricants
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• 제21권2호
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• pp.83-92
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• 2005

A piston assembly is very important because it directly receives the energy generated during combustion process. Surely, the friction and lubrication of piston-ring pack do an important role in the performance and fuel economy of an engine. In fact, the friction loss in piston-ring pack is the biggest portion to the whole engine friction. Therefore, the improvement of lubrication quality and friction loss in piston-ring pack will be directly related with the improvement in the performance and fuel economy of an engine. Meanwhile, the oil consumption and blow-by gas through piston-cylinder-ring crevices have to be controlled as less as possible. In these two aspects, the study on the optimized design of piston-ring pack has to be carried out. In this study, for the efficient design of piston-ring pack, it is focused to develop a basic computer program that predicts the inter-ring pressure, the motion of ring and the blow-by gas through a crevice volume model between adjacent rings, and the oil film thickness and the friction computed by lubrication theories.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.292-292
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• 2010

Bimodal Tram is driven by both engine and Lithium Polymer battery pack which consists with 168 cells of LPB(80Ah, 650Vdc). LPB pack is very frequently charged and discharged in driving. Temperature inside of LPB pack makes an great effect on both charging and discharging capacity which seem to be related with LPB internal resistance. LPB internal resistance is increasing or little decreasing with the decreased temperature under 10 - $20^{\circ}C$ and the increased temperature over $30^{\circ}C$ which is similar to the temperature characteristics of single LPB cell. This paper has analyzed the driving characteristics of LPB pack for bimodal tram is running with either battery mode or hybrid mode.

• Carbon letters
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• 제4권1호
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• pp.24-30
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• 2003

In this study, densified 4D carbon/carbon composites were made from carbon fiber and coal tar pitch through the process of pressure impregnation and carbonization and then followed by carbonization and graphitization. To improve the oxidative resistance of the prepared carbon/carbon composites, the surface of carbon/carbon composites was coated on SiC by the pack cementation method. The SiC coated layer was created by depending on the constitution of pack powder, and reaction time of pack-cementation. The morpology of crystalline and texture of these SiC coated carbon/carbon composites were investigated by XRD, SEM/EDS observation. So the coating mechanism of pack-cementation process was proposed. The oxidative res istance were observed through the air oxidation test, and then the optimal condition of pack cementation was found by them. Besides, the oxidative mechanism of SiC formed was proposed through the observation of SiC coated surface, which was undergone by oxidation test.

• 한국컴퓨터정보학회논문지
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• 제6권4호
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• pp.68-73
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• 2001

MPLS(Multi protocol Label Switching)는 Network Traffic 흐름의 속도를 높이고 관리하기 쉽게 하기 위한 표준 기술이다. MPLS는 정해진 Pack 열에 특정 경로를 설정하는 것에 관여하고, 각 Pack 내에는 라벨이 있어 Router 입장에서는 그 Pack을 전달할 노드의 주소를 확인하여 소요시간을 절약한다. MPLS는 IP, ATM및 프레임 릴레이 Network protocol 등과 같이 작동한다. MPLS는 Network OSI 참조모델과 함께 3Layer가 아닌 Switching을 하는 2Layer에서 대부분의 Pack이 전달되게 한다. MPLS는 Traffic을 빠르게 움직이게 하며, QoS를 위한 Network관리를 쉽게 한다. 이런 이유에 MPLS 기술은 더 많고 특정한 Traffic을 전송하기 시작한 Network로 채택될 유망한 기술로 기대되고 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.477-477
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• 2009

Bimodal Tram developed by KRRI is driven by a series Hybrid propulsion system which has both the CNG engine, generator and LPB(Lithium Polymer Battery) pack. It has three driving modes; Hybrid mode, Engine mode and Battery mode. Even in case of Battery mode, LPB pack to get enough power to drive the vehicle only by itself onsists of 168 LPB cells(80Ah per lcell), 650V. It is important thing to manage LPB pack in a right way, which will extend the lifetime of LPB cells and operate in the hybrid mode effectively. This paper has shown the development of battery management system(12 BMS, 1 BMS per 14cells) to manage LPB pack which is connected with CAN(Controller Area Network) each other and measure the voltage, current, temperature and also control the cooling fan inside of LPB pack. Using the measured data, BMS can show the SOC(State of Charge), SOH(State of Health) and other status of LPB pack including of the cell balancing.

• 한국정밀공학회지
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• 제33권10호
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• pp.813-820
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• 2016

Hybrid Electric Vehicles (HEVs) are developed to be operated with two kinds of power source (Diesel Engine and Electric Motor with Rechargeable High Voltage Battery Pack). HEVs for military vehicle require high reliability to provide stable powers under serious environment such as vibration and shock. To ensure normal operation of battery pack under serious environment such as vibration and shock, the high voltage battery pack needs to have appropriate dynamic characteristics. This paper presents a design procedure for high voltage battery pack with such characteristics. An isolator design is proposed to reduce vibration and shock. Associated random vibration and shock response of the high voltage battery pack are simulated under conditions suggested by MIL specifications. Its dynamic characteristics and vibration and shock responses are validated with experiments.

• 대한예방한의학회지
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• 제13권1호
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• pp.81-92
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• 2009

Objective : This study was designed to the effect of moxibustion therapy on the pain decrease and joint recovery with degenerative knee arthritis Methods : The research was administered from January to March 2008. The study subjects are menopause female 20 person and over 50 years old with degenerative knee arthritis patients, The Research were conducted with 10 moxibustion group and to 10 hot pack group during 4 Weeks. Results : 1. There is no significant difference of LSS of pre-treatment between hot pack group and moxibustion group(p<0.05). 2. There is no significant difference of LSS of post-treatment between hot pack group and moxibustion group(p<0.05). 3. There is no significant difference of LSS between pretreatment and post-treatment in hot pack group and moxibustion group(p<0.05). 4. There is no significant difference of VAS of pre-treatment between hot pack group and moxibustion group(p<0.05). Conclusion : This study suggests that hot pack used usually in physical therapy can decrease pain but the there is no significantly different between these two methods.

• 대한한의학회지
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• 제21권2호
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• pp.3-13
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• 2000

Objectives : In oriental medicine, Daeseungki-tang is one of the most useful prescriptions for the therapy of constipation. And we also frequently use this prescription for constipated stroke patients. Methods : In order to identify the effects of Daeseungki-tang on constipated stroke patients, we administrated the extract of Daeseungki-tang(code number, HH264) to constipated stroke patients. We gave the medicine in two ways, one-pack group and two-pack group by random allocation and investigated the amount of stool, the frequency of defecation, the stool-form and the changes of blood pressure and body temperature before and after defecation. We also tried to examine the difference of symptoms between defecation-group and non-defecation group. Results : 1. There were no distinct symptoms between defecation-group and non-defecation-group in one-pack group. 2. After defecation, body temperature decreased significantly(P<0.05) in one-pack group and blood pressure decreased significantly(P<0.05) in two-pack group. 3. As for the stool-form, watery-soft was 41.9% in the firstt defecation and 47.1 % in the second defecation. 4. In one-pack group(23 cases), 13 cases(57%) defecated and 10 cases(43%) didn't defecate. And in two-pack group(24 cases), 19 cases(80%) defecated and 5 cases(20%) didn't defecate. These results meant that the effect of Daeseungki-tang was dose dependent. The amount of stool and the frequency of defecation were also dose dependent.

• 한국포장학회지
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• 제23권3호
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• pp.173-181
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• 2017

본 연구에서는 한국의 가공식품 포장 특징(재질, 형태 등)을 분석하기 위해 다소비 식품에서 가공식품만을 대상으로 하여 품목별 소매점 매출액 순위에 따라 구성하였고, 이를 품목별 포장 형태, 품목별 포장 재질, 포장 형태별 포장 재질로 나누어 분석하였다. 또한, 품목별, 포장 형태별, 포장 재질별 접촉 비율과 두께를 측정하고 분석하였다. 국내 유통 중인 가공식품의 포장 재질별 사용 실태 조사 결과, 폴리에틸렌(PE, 43.61%), 폴리프로필렌(PP, 17.75%), 폴리에틸렌 테레프탈레이트(PET, 12.05%), 알루미늄(9.08%) 순으로 사용 빈도가 높아, 합성수지제를 가장 많이 사용하나 전반적으로 다양한 포장 재질을 사용하고 있는 것으로 조사되었다. 가공식품의 포장 형태별 사용 실태를 조사한 결과, EU 기준에 따른 포장 형태 총 21가지로 분류되었고, 가장 많이 쓰이는 포장 형태는 유연 포장재/봉투/파우치(38.96%)로 조사되었다. 본 연구는 가공식품 포장 재질, 포장 형태, 포장재 두께, 포장재와 식품의 접촉 비율 등의 구체적이고 방대한 양의 정보를 정리하여 국내의 가공식품 포장 현황을 반영한 조사로써, 향후 국내 식품포장 현황 분석 연구에 있어 기초 자료를 제공하는 데에 도움이 될 것으로 기대된다.

• 대한기관식도과학회지
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• 제6권2호
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• pp.201-203
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• 2000

The PTP (Press-Through-Pack) has been widely used as a packing material for tablets and capsules. But esophageal foreign bodies attributed to the PTP may cause injury to esophageal mucous membrane, potentially inducing severe complications such as hemorrhage, perforation, etc. We report three cases of PTP foreign bodies in esophagus with reference to recent literature.