• Transactions on Electrical and Electronic Materials
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• 제16권6호
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• pp.293-302
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• 2015

Degraded data stability, weaker write ability, and increased leakage power consumption are the primary concerns in scaled static random-access memory (SRAM) circuits. Two new SRAM cells are proposed in this paper for achieving enhanced read data stability and lower leakage power consumption in memory circuits. The bitline access transistors are asymmetrically gate-underlapped in the proposed SRAM cells. The strengths of the asymmetric bitline access transistors are weakened during read operations and enhanced during write operations, as the direction of current flow is reversed. With the proposed hybrid asymmetric SRAM cells, the read data stability is enhanced by up to 71.6% and leakage power consumption is suppressed up to 15.5%, while displaying similar write voltage margin and maintaining identical silicon area as compared to the conventional memory cells in a 15 nm FinFET technology.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2001년도 추계학술대회 논문집
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• pp.257-260
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• 2001

The primary objective of Supply Chain Management (SCM) is to optimize the cash, material and information flow considering all components of Supply Chain (SC) . The plan, established for achieving such objective, is called Supply Chain Planning (SCP) . This SCP gives each SC component specific volume or operation task, should be done in specific due date, for optimizing SC. In detail, the degree of accomplishment for SCP, depends on the SCP achievement of each SC components, is very close to successful SCM. However, this achievement is affected by uncertainties about time and volume. In general, reliability concepts means the probability that a product or system will perform its specified function under prescribed conditions without failure for a specified period of time. Therefore, the concept of Supply Chain Reliability (SCR) and an analytic methodology to calculate the degree of achievement SCP using reliability concept are proposed in this paper. SCR means that the degree of achievement for SCP considering all SC components in due date. SCR can be used to measure the performance of whole supply chain and indicate the direction of SCP.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.5-6
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• 2016

This paper introduces a high efficiency bidirectional resonant converter using an additional LC auxiliary circuit for dcdistribution applications. The LC auxiliary circuit operates as a variable inductor and the additional LC circuit helps to increase the effective magnetizing inductance, thereby reducing the turn-off and primary circulating current. A 5 kW bidirectional converter for dc-distribution system is implemented to verify the validity of the proposed method. The experimental results show the high efficiency characteristics of the proposed converter over the wide range of load in both direction of power flow. The maximum efficiency of the proposed system was 98.1 % at 3 kW.

• Structural Engineering and Mechanics
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• 제63권4호
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• pp.567-574
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• 2017

Sedimentation tanks are essential structures to filter the suspended sediments in the inlet flow which are constructed at the inlet of the basins forked from rivers and irrigation canals. The larger the constructed tank, the better the sedimentation process is conducted. However, the construction and dredging costs increase. In this regard, improving the performance and sedimentation efficiency seem necessary by alternative methods. One of these effective methods is using baffle plates. Most of the studies carried out in this field are on the use of these baffles in the primary and secondary sedimentation tanks. Hence, this study is carrier out with the objective of increasing the retention efficiency in the irrigation sedimentation tanks using baffles. To reach this goal, the experiments were carried out in a flume with length 8 meters, width 0.3 meters, and height 0.5 meters, considering a sedimentation tanks with a length of 3 meters, in three different inlet concentration, three flow rates and three Froude numbers. The baffles were mounted at the bottom of the tank and the effects of the angle, height and position in the tanks were investigated. The results showed that on average, employing the baffles increased the sedimentation efficiency 5 to 6% and the highest value was obtained for angle 60 with respect to the flow direction. According to the results of this study, the most favorable height and position of these baffles were obtained to be in 40% of the depth of the flow and 50% of the length of the sedimentation tank, respectively. Also, by increasing the number of baffles, the sedimentation efficiency decreased. Regarding the sedimentation regions in this case, more than 80% of the settled sediments were observed in the middle of the tank measured from the inlet.

• 터널과지하공간
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• 제8권4호
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• pp.332-341
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• 1998

석판재의 모서리 가공작업은 많은 경우 자동화가 이루어지고 있지만 제품의 형태 가 복잡해지면 여전히 수작업에 의해 연마가 이루어지고 있다. 본 논문을 성형공구의 제작 에 앞서 성형공구의 특성과 장비의 운영요소들의 변화에 따른 연마절삭성능을 파악하기 위 한 기본시험이 수행결과를 나타내는 것이다. 장비의 운영요소는 헤드의 회전속도 및 이송속 도, 가압하중, 급수율, 절삭방향과 이송방향이 포함된다. 실험결과는 연마절삭성능 즉 공구 마모 무게에 대한 판재의 절삭량으로 표시하였고, 각 운영요소들 마다의 적정 운영수준이 제시되어 있다. 또한 연마재 투입략의 변화에 대한 마모시험에서는 마모도는 연마재의 증가 에 따라 증가하지만 어느 이상의 양에서는 오히려 감소하고 있다.

• 한국정보교육학회:학술대회논문집
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• 한국정보교육학회 2004년도 하계학술대회
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• pp.28-37
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• 2004

제7차 교육과정의 시행과 함께 본격화된 교육 정보화에 대한 노력으로 일선 학교의 각 교과별 수업에서 ICT를 활용하여 교육 정의화를 구체적으로 실현하는 시점에 이르렀다. 그러나 이러한 현실적인 시급함에도 불구하고, 아직까지 실제적인 ICT 도입방향이나 활용 방안에 대한 구체적인 논의와 연구가 충분히 이루어졌다고 보기는 어렵다. 학년 급별로 정보통신기술과 관련된 목표를 정하고 학습자들을 체계적으로 가르친다는 계획은 그 자체로서 매우 가치가 있는 일이나 그 수준과 목표를 어떻게 설정하는가는 교육의 성공 여부와 직결되는 문제라는 점에서 상당한 논의와 실험을 거쳐야 할 것이다. 따라서 본 연구는 초등 교과에 나오는 각 교과의 교육 목표를 분석하고 외국 교육과정을 분석해 봄으로써 초등학교에서 컴퓨터 교육 목표를 제언하고자 하였다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.467-470
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• 2006

Superconducting fault current(SFCLs) are expected to improve not only reliability but also stability of real power systems. The analysis on the single line-to-ground fault current of the integrated three phase flux-lock type SFCL, which consists of three flux-lock reactor wound on an iron core in each single phase and three YBCO thin films, was investigated in current limiting operating characteristics. We compared additive polarity winding with the subtractive one in the flux lock reactor. Its turns ratio each phase between the primary and the secondary coils is 63:42. When a single line-to-ground fault occurred in any phase, the peak value of line current in the fault phase of the additive polarity winding increased up to 31.44[A] during first-half cycle. On the other hand, the peak value in the subtractive polarity winding increased up to 81.77[A] under the same conditions. This is because the current flow between the primary and the secondary windings becomes to be additive or subtractive in each winding direction. We confirmed that the current limiting behavior in the additive polarity winding was more effective for a single-line-to ground fault.

• 대한가정학회지
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• 제36권9호
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• pp.13-33
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• 1998

The purpose of this study is to examine the styles of street fashion in youth sub-culture which has the leading power of 1990's Korean fashion flow. This topic has been explored in documentary studies about the youth sub-culture and the background of street fashion. Then, it also continued to classify street fashion styles in order to grasp the meaning as a young fashion. The results of this study are as follows. Street fashio of Korean youth are composed of four styles. ; The first is a hip-hop style. The hip-hop of Korea is started by 'Taiji Boys' and their representative apperances are the big-baggy pants, the reversed cap, the thrown backpack. The second is a reggae style. It is formed by the singer 'Kim Gun Mo'. It features the primary color and the use of ethnic fabrics. The third is a kitch style. The kitch is definitely represented by the old, the childish and the satire appearances. It came up with the rock band 'pipiband'. The forth is a sporty style. It comes from 'basketball' and 'skateboarding' which the young people prefer. Its designs are applied from the back-number of players, the names of the teams, the stripes of active-feeling. Based on this study, I designed cloths with 3 concepts to present a new design direction of Street Fashion. Work 1, 「JOY-RIDE」 represented the freedom and the release which are shown by pop music and dance. Work 2, 「GAMMA ENERGY」 represented the dynamic energy through sports games. Work 3, 「AROUND THE CORNER」 represented the form of street including comers, walls, roads etc.

• 대한조선학회논문집
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• 제50권2호
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• pp.88-94
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• 2013

The primary objective of the current work is to obviously analyze regarding effects of trim conditions of a ship on resistance performance using model test and CFD. Model tests at a towing tank are conducted to investigate resistance for trim conditions at the given same displacement. Measured resistance shows small but distinct differences according to trim conditions. However, these differences are difficult to be clarified by measured physical quantities and wave pattern analysis from model tests. CFD is employed for the assessment of resistance performance according to trim conditions. The flow computation is conducted considering free surface and dynamic trim using a commercial CFD code (STAR-CCM+). The initiative of the present work is to systematically demonstrate pressure resistance acting on each region of divided finite zones of ship surface along the length and draught direction of surface when pressure distribution on the ship is interpreted. Also, a standard to assess the pressure resistance applied on the divided regions of a ship is established.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.314-319
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• 2003

The concept of lean-premixed combustion in gas turbine combustor operation has become a standard in recent years as an effective means to meet stringent enviromental standards on NOx emissions. The combustion characteristics of 75 kW class lean premixed combustor were investigated at the conditions of high temperature and ambient pressure. The exit temperature and emissions of CO and NOx were measured at the center of exit plane. The high temperature air of $550K{\sim}650K$ was supplied through air preheater. As expected, experimental results indicate that NOx emission was increased and CO emission was decreased by increasing inlet air temperature. But CO emission measured at the center of exit plane was increased because of the non-uniform radial direction profiles. The Semi-Empirical Correlation method was applied to obtain the design point emissions of NOx and CO. Also the flame temperature, CO and NOx emissions were measured along the centerline of liner at 650K inlet air temperature to determine the position of dilution holes.