• 제목/요약/키워드: Dwell

검색결과 347건 처리시간 0.034초

A Study on the Effects of Ignition Energy and Systems on the Flame Propagation in a Constant Volume Combustion Chamber (정적연소기에서 점화에너지와 점화장치가 화염전파속도에 미치는 영향에 관한 연구)

  • 송정훈;서영호;선우명호
    • Transactions of the Korean Society of Automotive Engineers
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    • 제9권1호
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    • pp.45-56
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    • 2001
  • A constant volume combustion chamber is employed to investigate the initial flame kernel development and flame propagation of gasoline-air mixtures with various ignition systems, ignition energy and spark plug electrodes. To do this research, four ignition systems are designed and manufactured, and the ignition energy is controlled by varying the dwell time. Several kinds of spark plugs are also made to analyze the effects of electrodes on flame kernel development. The velocity of flame propagation is measured by the laser deflection method. The output laser beam from He-Ne laser is divided into three parallel beams by a beam splitter. The splitted beams pass through the combustion chamber. They are deflected when contacted with flame front, and the voltage signals from photodiodes change due to deflection. The results show that higher ignition energy raises the flame propagation speed especially under the fuel lean operation. The wider electrode gap, smaller electrode diameter and sharper electrode tip make the speed of the initial flame propagation faster. The speed of the initial flame propagation is affected by electrode material as well. Electrode material with lower melting temperature help the initial flame propagation.

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A Study on the Evaluation of the Dwelling Environment in the Types of Residential Area (도심지역의 거주환경평가에 관한 연구 - 대구 도심 지역 거주자를 대상으로 -)

  • 신소영
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 한국주거학회 1994년도 학술발표대회논문집 상
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    • pp.29-36
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    • 1994
  • The purpose of this study is to suggest the basic design elements for dwelling environment planning of downtown in Taegu.The evaluation of the dwelling environment should be approached from the satisfaction and the cognitive of the residents, that are based on their desire and various values on the conditions of residential area. This paper concerns the satisfaction and the congnitive image structure of the residents in the various dwelling types, from which design elements for dwelling environments can be derived. The results are as folIows: 1) The analysis on the satisfaction of dwell ins environment shows lots of displeasure about the lack of open-spaces and the housing low-quality, neighborhood in Mun-hwa, Korean style housing and the low-rise apartment areas. In order to make the variety types of dowelling in downtown district, the improvement of housing qualities and the expantion of the urban facilities for the open-spaces and communities are need. 2) The design elements of dwelling environments in downtown find out the important planning elements for urban design. The evaluation of the cognitive image structures about the safety and affection should be considered in design for urban dwelling areas.

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Effect of Calendering Variables on the Properties of Coated paper (캘린더 처리조건이 도공지 품질에 미치는 영향)

  • 이용규;김창근;이광섭
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • 제33권2호
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    • pp.49-57
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    • 2001
  • This study was performed to identify the effect of calendering variables on the properties of coated paper such as sheet gloss, surface roughness, opacity, etc. The effect of calendering variables including the number of nips, pressure, machine speed and moisture content on the properties of coated paper was investigated. The calender was installed with two steel rolls and one cotton-made roll. With this calender, the coated sheets were passed through the calender from 1 to 4 times, applying the linear pressure on calender rolls, 5 through 100kg/cm and operating the machine speed 3 to 12m/min. Also, the moisture content of coated sheet was varied about 5 and 10%. It was found that sheet gloss and surface roughness of coated paper was increased with increasing the number of passing nips, linear roll pressure and the moisture content of coated paper. But it was shown that the opacity and brightness of coated paper were decreased under the above conditions due to the blackening. It was also suggested that the soft nip possibly increased the thermoplasticity of coating layer with the heat of steel roll, resulting in the reinforcement of surface properties positively. The sheet gloss and surface roughness of coated paper could be improved by the longer dwell time over the rolls.

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A Study on the Standard Requirements of the Tabernacle's Representation Drawings through Architectural Analysis (건축학적(建築學的) 해석(解析)에 의한 성막건축(聖幕建築)의 재현설계(再現設計) 기준설정(基準說定)에 관한 연구(硏究))

  • Oh, Tae-Joo;Lee, Sang-Ho
    • Korean Institute of Interior Design Journal
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    • 제16권1호
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    • pp.108-118
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    • 2007
  • The tabernacle architecture is the paradigm of the new testaments and the modern church, and has been from the temples to synagogues, the Old Testaments to the New Testaments, and from present to future. Nevertheless, research on the Tabernacles has never been studied architecturally but has only been researched Biblically or partially. This would be because people interested in the tabernacle lack in architectural knowledge, and architects would be limited theologically. Furthermore, the start of church architecture until now was the architecture of the Roman-court style and the Greece Temple as the exterior, such as the Basilica, a non-Christian, strangely styled piece of architecture, which was seen as the basis of the church architectural style, which is a great mistake, due to the effect of modern architectural educational system with the central figure of humanism and western styled architecture. The measurement and the pattern of the Tabernacle architecture were not recorded in the Bible in order to produce the shape of the Tabernacle. The 'Architecture of God' was designed for the very first time on Earth so that He could dwell among His people.

On Improving the Productivity of Busan Container Terminal (부산 컨테이너 부두의 효율적인 운영방안에 관하여)

  • 이병국;이철영
    • Journal of the Korean Institute of Navigation
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    • 제11권1호
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    • pp.39-65
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    • 1987
  • Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.

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Study on Switching Angle Characteristics for Driving Performance Improvement of SRM Drive (SRM 드라이브의 운전성능 향상을 위한 스위칭각 특성에 관한 연구)

  • 오석규;최대완;안진우
    • The Transactions of the Korean Institute of Power Electronics
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    • 제6권6호
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    • pp.506-513
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    • 2001
  • The torque of an SRM depends on the phase current and derivative of inductance. But an SRM is difficult to control the desired torques because of saturation in magnetic circuit An SRM is controlled by parameters of input voltage, and switch on , off angle The switch on off angles of an SRM regulate the magnitude and shape of current waveform and decide the magnitude and shape of torque This paper proposes an the optimization control scheme by adjusting both the switch on an switch off angle . The switch off angles are decided by reference of efficiency using simulation and experiments. The switch on angles are decided by load torque , And the dwell angles are controlled for torque control and speed control using GA-neural network which is used to simulated the reasonable switching angle.

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Resistivity Changes and Intermetallic Growth After Thermal Aging of Matte Tin-Plated Copper Sheet for Current Collector in Fuel Cell (연료전지 집전판용 주석도금 동판의 열 열화에 따른 금속간화합물 성장 및 비저항 변화)

  • Kim, Jae-Hun;Kim, Ju-Han;Han, Sang-Ok;Koo, Kyung-Wan;Keum, Young-Bum;Jeong, Kwi-Seong;Ko, Haeng-Zin
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2067_2068
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    • 2009
  • Resistivity changes and intermetallic growth after thermal aging of Matter tin-plated copper sheet for current collector in fuel cell were investigated to survey the diffusion of Cu into Sn in interface and surface. The results show that the intermetallic growth and resistivity depended on thermal aging temperature and dwell time. In Sn plate on a Cu substrate, $Cu_6Sn_5({\mu})$ and $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface. $Cu_6Sn_5({\mu})$ intermetallics layer gradually changed $Cu_3Sn({\varepsilon})$. Moreover Cu get through Sn layer and it was diffused in the surface at $200^{\circ}C$. On the other hand, only $Cu_3Sn({\varepsilon})$ intermetallics layer were formed at plate/substrate interface at $300^{\circ}C$. Consequently, the intermetallics formation, thermal condition and oxidation of surface, causes increase in the resistivity of Tin-plated copper sheet.

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The Influence of Parameters Controlling Beam Position On-Sample During Deposition Patterning Process with Focused Ion Beam (빔 위치 관련 제어인자가 집속이온빔 패턴 증착공정에 미치는 영향)

  • Kim, Joon-Hyun;Song, Chun-Sam;Kim, Youn-Jea
    • Transactions of the Korean Society of Mechanical Engineers A
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    • 제32권3호
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    • pp.209-216
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    • 2008
  • The application of focused ion beam (FIB) depends on the optimal interaction of the operation parameters between operating parameters which control beam and samples on the stage during the FIB deposition process. This deposition process was investigated systematically in C precursor gas. Under the fine beam conditions (30kV, 40nm beam size, etc), the effect of considered process parameters - dwell time, beam overlap, incident beam angle to tilted surface, minimum frame time and pattern size were investigated from deposition results by the design of experiment. For the process analysis, influence of the parameters on FIB-CVD process was examined with respect to dimensions and constructed shapes of single and multi- patterns. Throughout the single patterning process, optimal conditions were selected. Multi-patterning deposition were presented to show the effect of on-stage parameters. The analysis have provided the sequent beam scan method and the aspect-ratio had the most significant influence for the multi-patterning deposition in the FIB processing. The bitmapped scan method was more efficient than the one-by-one scan type method for obtaining high aspect-ratio (Width/Height > 1) patterns.

A Study on Railroad Track Capacity According to Transit Railway Demand (철도이용수요에 따른 선로용량 변화 분석 연구)

  • Kim, Ickhee;Kim, Incheol;Bae, Yeong-Gyu;Wang, Yeondae
    • Journal of the Korean Operations Research and Management Science Society
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    • 제38권3호
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    • pp.23-35
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    • 2013
  • It is very important that the calculation of railroad track capacity in infrastructure investment analysis and train operation planning. The dwelling time is one of the factors that influence in railroad track capacity. Current research in dwelling time has been focusing on theoretical investigation, the state of the research in effective variable (dwelling time etc) is insufficient. In this paper, we clearly draw the concept of railroad track capacity and the estimate on modeling of relationship railway demand and dwelling time. Also, we compare and analyze the variation of railroad track capacity according to transit railway demand in Gyeongin Line (Guro~Inchon). This paper is expected to contribute for improving on the in-using equations and methods in train operation planning as well as for improving level of service on railway user.

Thoughts on the phrase "夫氣之在脈也" of Miraculous Pivot(靈樞)·Nine needles and Twelve sources(九鍼十二原) (≪영추(靈樞)·구침십이원(九鍼十二原)≫의 "부기지재맥야(夫氣之在脈也)"구절에 대한 소고(小考))

  • Jeong, Chang-Hyun
    • Journal of Korean Medical classics
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    • 제27권4호
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    • pp.21-27
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    • 2014
  • Objectives : Among the translations of the verse "Sa-gi is on the upper side, Tak-gi is on the middle side, Cheong-gi is on the under side(邪氣在上, 濁氣在中, 淸氣在下)" in the texts of Miraculous Pivot(靈樞) Nine needles and Twelve sources(九鍼十二原), the meanings of 'Ham-maek(陷脈)' and 'Joong-maek(中脈)' have contradictory versions. Methods : This study will identify the actual meaning of this verse through analysis of the phrase "夫氣之在脈也", followed by examination of the relationship between the meaning of "three-stratum puncture(三刺)" in the chapters Miraculous Pivot Handling needle(官鍼), Miraculous Pivot Jong-si(終始) and the meaning of "刺有三變" of Miraculous Pivot Longevity and character(壽夭剛柔), after which its application in later periods will be discussed. Results : The words 'Sa-gi', 'Tak-gi' and 'Cheong-gi' in the phrase "夫氣之在脈也" of Miraculous Pivot Nine needles and Twelve sources each correspond to the words 'yang pathogens(陽邪)', 'yin pathogens(陰邪)' and 'essence derived from food(穀氣)' of Miraculous Pivot 終始, respectively. Conclusions : The Upper-Middle-Lower of the phrase "夫氣之在脈也" in Nine needles and Twelve sources indicates the three levels of depth, in which 'Sa-gi', 'Tak-gi' and 'Cheong-gi' each dwell. 'Ham-maek' and 'Joong-maek' are categorizations according to the depth of needling.