• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1285-1296
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• 2011

Packet classification is one of the basic and important functions of the Internet routers, and it became more important along with new emerging application programs requiring real-time transmission. Since packet classification should be accomplished in line-speed on each incoming input packet for multiple header fields, it becomes one of the challenges in designing Internet routers. Various packet classification algorithms have been proposed to provide the high-speed packet classification. Hierarchical approach achieves effective packet classification performance by significantly narrowing down the search space whenever a field lookup is completed. However, hierarchical approach involves back-tracking problem. In order to solve the problem, set-pruning trie and grid-of-trie algorithms are proposed. However, the algorithm either causes excessive node duplication or heavy pre-computation. In this paper, we propose a smart set-pruning trie which reduces the number of node duplication in the set-pruning trie by the simple merging of the lower-level tries. Simulation result shows that the proposed trie has the reduced number of copied nodes by 2-8% compared with the set-pruning trie.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.25-30
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• 2009

The present study deals with numerical investigation for smoke behavior in rescue station by using the commercial CFD code (FLUENT Ver 6.3). With the use of the MVHS(Modify Volumetric Heat Source) model modified from the original VHS(Volumetric Heat Source) model, a 10 MW mode was adopted for simulation and the MVHS model can describe the generation of product and the oxygen consumption at the stoichiometric state. In addition, the present simulation includes the species conservation equations for the materialization of heat source and the estimation of smoke movement. From the results, the smoke flows are moving along the ceiling because of thermal buoyancy force and as time goes, the smoke gradually moves downward at the vicinity of the entrance. Moreover, without using ventilation, it is found that the smoke flows no longer spread across the cross-passages because the pressure in the non-accident tunnel is higher than that in the accident tunnel.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.400-405
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• 2011

This paper presents the heating performance characteristics of the air source heat pump with air to water type. The heating capacity, COP, P-h diagram were measured at various operating conditions, air-side temperatures, relative humidities, and inlet/outlet water temperature under the standard heating condition of KS B 6275. The experimental data for the heat pump were measured using the air-enthalpy calorimeter and the constant temperature water bath. As the air-side temperature increases, the heating capacity and COP increase. The effect of the air-side relative humidities on the heat pump performance is insignificant. The heat pump performance on inlet and outlet water temperatures and air-side temperatures(-7, -11, $-15^{\circ}C$) were studied. Heating capacity and COP increased about 27~39% with the air-side temperature increasing. Enthalpy between the front and the rear of condenser decreased about 6% by increasing of the inlet water temperature. These results can be utilized in the design of the air source heat pump system with air to water type.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.205-210
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• 2018

We will investigate in depth the reasons why companies have a negative mindset and produce complaints about the internship system itself. On the other hand, we try to find out the success factors of domestic companies that have introduced and operate the exemplary internship system, and prepare policies to disseminate them. In order to do this, I would like to diagnose the problems related to the internship system in the current industry through questionnaires or interviews with existing internship students. It is hoped that this will help the participating students to have a positive mindset about the company and further contribute to the career search and adaptation to the firm from the university to the firm.

• Korean Journal of Materials Research
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• v.17 no.6
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• pp.293-297
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• 2007

Microstructure and tensile strength of the vacuum brazed stainless steel(STS303) and Cu were investigated. For brazing, the BNi-2, 3, 4, 6 and 7 (A.W.S standard) were used as filler metals. The Oxides such as $Cr_2O_3$ and $SiO_2$ were observed at brazed layers between STS303 and Cu matrix. Also, the intermetallic compounds of Cr-B and Ni-P were observed at brazed layers. Brazed STS303-Cu specimens with BNi-2, 3, 4 filler metals showed almost elastic deformation followed by plastic yielding and strain hardening up to a peak stress. On the other hand, it is likely that the fracture of the brazed specimens with BNi-6 and 7 was occurred in elastic range without plastic yielding up to a peak stress. Among these filler metals, the BNi-2 brazed at $1050^{\circ}C$ showed excellent wettability and the highest tensile strength (101.6MPa).

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.768-777
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• 2009

The characteristics of stormwater runoff was examined on distinct types of agricultural and industrial area in Lake Sihwa watershed. During rainfall event, the peak concentrations of SS, $COD_{Mn}$, and TP were observed after 6~11 hours of rainfall in agricultural areas. Whereas, the peak concentrations occurred within the first one hour after rainfall and then the highest concentration of NPS pollutants sharply decreased, showing strong first flush effect in industrial areas. The strong first flush effect of suspended solid was apparent in agricultural areas, while those of organic matters and nutrients were clear in industrial areas. The cumulative load curves for NPS pollutants showed above the $45^{\circ}$ straight line, indicating that first flush effect occurred in industrial areas. The mean SS EMC values of agricultural areas ranged from 60~598 mg/L (Avg. 285 mg/L), it was higher value when compare to other areas. While the mean $COD_{Mn}$, TN, and TP EMCs values of industrial areas were shown the highest values as 67.7 mg/L, 12.1 mg/L and 2.1 mg/L respectively.

• The Inventors News
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• no.55
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• pp.1-16
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• 2007

선진국가 선도하는 창의적 여성경제리더 양성하자/발명지도사.시제품제작지원 시행/발행인 칼럼/특허심사처리 세계에서 가장 빠르다/글로벌 기업, 한국 특허청에 심사의뢰 쇄도/국유특허권 온라인 전자계약 시행/특허기술, "기술경매" 로 산다/여성발명인 거유 활동 영역 넓어/감귤와인 특허획득 이어 독일 등 해외 수출 기대/미더덕 냉동 않고도 장기 보관/특허민원서식 대폭 감축/특허청, 개도국 지원사업 대폭 확대/기상청, 날씨예보기술로 특허 받아/우리나라 국제특허출원 수준 세계 6위/건강관련 브랜드 상표출원 증가/친환경수로관 '도룡용 살린다'/고등학교에 첫 발명창작과 개설/욕조, 웰빙 휴식공간으로 자리매김/가습기, 공기정화.탈취.방향 등 다기능화/패치제 특허출원 해마다 증가/일 특허청, 분할출원기간 30일 연장/중 법원, 비아그라 특허군 인정/국내 제약사 유유 "미머크사 특허 침해" 주장/삼성전자, 지난해 미 특허 2천4백53건으로 2위/기업심볼마크는 단순, 상표는 길어져/LG전자 "대우일렉이 드럼세탁기 특허권 침해했다"/유.무선 통합 '원폰 서비스' 기술 개발/암환자 울린 과대광고제품 1백억원대 판매 적발/맥도날드 '해피밀' 광고 퇴출/세원셀론텍, 콜라겐 원천기술 특허/역사 속의 발명품/하루 10분 발명교실/특허Q&A/'S&D Trecap' 황지경 대표/경기도, 여성분야 소상공인창업자금 신설/특허청, 세계지식재산기구(WIPO) 진출확대/아이디어 착상 및 발명 기법/여성발명 활성화만이 국가경쟁력 키우는 첩경/히로자키의 광엽수 진액/해외 네티즌 인기 화제의 발명품들/여성기업 생산제품 MAS시 적격성 평가 면제/특허청, 시작품제작지원 5천만원까지 확대/지난해 짝파라치에게 3억2천3백만원 포상금 지급/입체방송 분야 특허출원 봇물/트랜스지방 퇴출 시민단체 '토트랜스 클럽' 출현/한국여성발명협회 회원사 발명품 가이드/

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.307-312
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• 2011

As a technique for removing cancerous tumors from normal tissue, radio-frequency electromagnetic waves were employed to heating target cells up to the critical temperature, which kills the cancerous cells. However, its use in treating tumors in soft organs is limited by inconvenient factors, which are use of high-currents and long time operation. In this work, the feasibility of the localized heating by inserting four conducting electrodes with tiny direct current is investigated. The heat source is resulting from the electric field as known as resistive heating. We have investigated the temperature distribution as a function of applying DC voltages ranging from 10 V to 30 V with 10 V step. From the simulation results, the mushroom-like lesion shape by applying 20 V is generated by four electrodes within a few minutes, that is proper to the clinical application.

• Plant Journal
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• v.10 no.4
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• pp.35-41
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• 2014

The height and capacity of the thermal storage tank can be decided by the altitude and heat load of the heat supply area. Evaporation in heat pipe can be prevented by pressurizing it with the hydraulic head of the thermal storage tank. In addition, it absorbs the expanded volume from the temperature changes and supplies water to the pipelines in case of the shortage of water. One of the most important roles of the thermal storage tank is a stable heat supply facility. It can control the heat demand by accumulating the surplus heat and supplying in changing heat demand time. The purpose of this thesis is to be helpful for the operation and maintenance of the thermal storage tanks. The study has been carried out for 18 thermal storage tanks, which have been used polyurethane foam as insulation, among 27 tanks in district heating plants. The characteristics of the insulation materials, the reasons for the damages of the insulation and how impact the insulation damages to the corrosion of the thermal storage tank have been studied.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.11
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• pp.1010-1015
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• 2012

In this study, a thin-film thermo-electrochemical cell that directly converts waste thermal energy into electrical energy was fabricated. Electrical conductivity of conducting carbon fiber, which was used as flexible electrode, was increased through coating of carbon nanotube, and resistance of the CNT-coated fiber electrode was not changed even after bending test with various curvatures. Maximum output power of the thermocell was increased quadratically with the temperature difference, and showed a value of about 2.5 mW/kg at temperature difference of $3.4^{\circ}C$. As a result of discharge test for 12 hours, it is confirmed that the cell can operates continuously. And thin-film thermocell wrapped around a pipe with hot liquid flowing within was demonstrated. Internal resistance of the cell was decreased with various curvature of heat pipe, and maximum output power was increased by 30 %. Therefore, the cell can be applied to various heat source.