• Title/Summary/Keyword: Series Flow Cycle

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Effect of Liquid Circulation Velocity and Cell Density on the Growth of Parietochloris incisa in Flat Plate Photobioreactors

  • Changhai Wang;Yingying Sun;Ronglian Xing;Liqin Sun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.2
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    • pp.103-108
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    • 2005
  • For more accurately describing the durations of the light and the dark phases of micro-algal cells over the whole light-dark cycle, and probing into the relationship between the liquid circulation time or velocity, the aeration rate and cell density, a series of experiments was carried out in 10 cm light-path flat plate photobioreactors. The results indicated that the liquid flow in the flat plate photobioreactor could be described by liquid dynamic equations, and a high biomass output, higher content and productivity of arachidonic acid, $70.10\;gm^{-2}d^{-1},\;9.62\%$ and 510.3 mg/L, respectively, were obtained under the optimal culture conditions.

Exploring a BIM-based approach of project management

  • MA, Xiaozhi;XIONG, Feng;DONG, Na
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.241-244
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    • 2015
  • Within the building industry, building information modelling has been widely applied among different organizations, disciplines and project phases. In order to achieve coordination and synergy collaborative effort, it demands organized information flow and communication for effective implementation of project management through the construction process. Although many BIM researches provides solutions for project management, few efforts have involved the whole life-cycle process of project. In this article, BIM-based project management relying on a series of applications of BIM technology was introduced by coupling management requirement of a project with BIM. Through adopting BIM to the life-cycle management of the project and incorporating BIM applications to project management practice, we have developed a BIM-based project management approach that specialize in integrated BIM chain and interface-supporting system. At the end, the developing process of BIM-based project management approach is concluded.

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Analysis of Fashion Design Characteristics and Cycles of Knit Fashion Trends (디자인 특성에 따른 니트 패션 트렌드의 주기 분석)

  • Ko, Soon-Young;Park, Young-Sun;Park, Myung-Ja
    • The Research Journal of the Costume Culture
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    • v.18 no.6
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    • pp.1274-1290
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    • 2010
  • This study analyzed the design elements and fashion images of women's knitwear in collections of Paris, Milan, London and New York between 2003 and 2008, and examined knitwear trends in an effort to verify whether knitwear trends are repeated in certain cycles, whether they show complicated patterns in cycles and yet occur in quasi cycles, or whether they occur non-periodically in complicated forms of chaotic cycles. Trend cycle analysis results are deemed to identify the time series attribute of knit fashions. It also sought to categorize the attribute of various factors influencing knitwear trends with a view to determining relevancy between design elements, and to present the direction of predicting knitwear fashion trends and the progression of short-term knitwear trends. This study reached the following conclusion. According to design elements or fashion images, knitwear fashion trends occur in cycles, quasi cycles, non-periodical cycles. These cyclic characteristics can be used as scientific data for planning knitwear products. The study confirmed close relevancy between fashion images and fashion elements. It identified close relevancy between designs with similar fashion elements and images through coordinates by year and season, and it is possible to make short-term prediction of trend direction through the flow of coordinates. Time series data were insufficient, thereby making it difficult to perfectly verify chaos indices and giving limitations to this study. A study with more time series data will produce a more effective method of predicting and using knitwear fashion trends.

Training Sample of Artificial Neural Networks for Predicting Signalized Intersection Queue Length (신호교차로 대기행렬 예측을 위한 인공신경망의 학습자료 구성분석)

  • 한종학;김성호;최병국
    • Journal of Korean Society of Transportation
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    • v.18 no.4
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    • pp.75-85
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    • 2000
  • The Purpose of this study is to analyze wether the composition of training sample have a relation with the Predictive ability and the learning results of ANNs(Artificial Neural Networks) fur predicting one cycle ahead of the queue length(veh.) in a signalized intersection. In this study, ANNs\` training sample is classified into the assumption of two cases. The first is to utilize time-series(Per cycle) data of queue length which would be detected by one detector (loop or video) The second is to use time-space correlated data(such as: a upstream feed-in flow, a link travel time, a approach maximum stationary queue length, a departure volume) which would be detected by a integrative vehicle detection systems (loop detector, video detector, RFIDs) which would be installed between the upstream node(intersection) and downstream node. The major findings from this paper is In Daechi Intersection(GangNamGu, Seoul), in the case of ANNs\` training sample constructed by time-space correlated data between the upstream node(intersection) and downstream node, the pattern recognition ability of an interrupted traffic flow is better.

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MR Line Scan Angiography using Spectral Analysis

  • Jung, Kwan-Jin;Ro, Yong-Man;Sim, Bog-Tae;Ra, Jong-Beom;Cho, Zang-Hee
    • Proceedings of the KOSOMBE Conference
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    • v.1989 no.05
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    • pp.27-28
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    • 1989
  • In conventional line scan angiography, flow signal has been enhanced by the time_of_flight effect while the signal from stationary tissues has been suppressed by the saturation rf pulse followed by spoiling gradients. Due to the inhomogeneous rf field and the tissue dependent T1 relaxation time, however, stationary tissues can not be suppressed completely or uniformly, and the remnant stationary signal deteriorates the resultant angiogram. Here, the complete cancellation of stationary tissues is made possible by the spectral analysis of a series of repetitive line images of the same slice. The Fourier transformation of a set of line images results in the spectrum images, where stationary tissues are collected into the dc component while arteries are included in harmonic components because of the variation of the flow velocity and the resultant flow signal in arteries according to the cardiac cycle. The summation of harmonic components excluding the dc component results in the angiogram of arteries with the complete cancellation of stationary tissues.

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The Performance Evaluation of R407C and R410B in a Residential Window Air-Conditioner

  • Kim, Man-Hoe;Shin, Jeong-Seob;Kim, Kwon-Jin
    • International Journal of Air-Conditioning and Refrigeration
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    • v.6
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    • pp.148-157
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    • 1998
  • This study presents test results of a residential window air-conditioner using R22 and two potential alternative refrigerants, R407C and R410B. A series of performance tests has been carried out for the basic and liquid-suction heat exchange cycles in a psychometric calorimeter test facility. For R407C, the same rotary compressor was used as in the R22 system. However, compressor for the R410B system was modified to provide the similar cooling capacity. The evaporator circuit was changed to get a counter-cross flow heat exchanger to take advantage of zeotropic mixture's temperature glide, and liquid-suction heat exchange cycle was also considered to improve the system performance. Test results were compared with those for the basic R22 system. The modified system with a liquid-suction heat exchanger increased cooling capacity and energy efficiency by up to 5%.

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공정분석(工程分析)에 관(關)한 세부적용(細部適用) 기법(技法) 보고(報告)

  • Gyeong-Il,Kim;Jong-Ho,Kim
    • Bulletin of the Society of Naval Architects of Korea
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    • v.19 no.2
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    • pp.41-60
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    • 1982
  • The main idea of this report, which deals with the process analysis in outfitting fields, is to improve working methods and further to secure higher productivity by removing unreasonable work factors in the workshop with the economical point of view. For this purpose, a series of techniques has been applied to some parts of chronically less productive outfitting works, expecting less man hour consumption and better working conditions to go with it. That is to make full use of process chart flow diagram(man & machine chart gang process chart). The text gives brief introductions of the charts respectively and the appendix shows actual practice directly applicable for the guidance of utilizing these charts. As the result of this, some of unreasonable work factors are removed from the total cycle and finally standard working method & time can be come out by reasonable working time and gradually improved working method.

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Influence affected on the curvature radius of jar by circuit of cooling temperature and temperature control (냉온회로 및 제어가 JAR곡율반경에 미치는 영향)

  • Shin, Nam-Ho;Choi, Seok-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.6
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    • pp.1313-1318
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    • 2007
  • When the mold is cooled suddenly to reduce the time for forming work and improve the quality of jar50ml which is different highly at rib thickness by a series of various curvature radii, the poor quality of void, flow and deformation happens. The structure of spiral cooling circuit at cavity and core can control the temperature of inner and outer side sufficiently. And the system can control cooling and heating automatically. These things are applied to Jar mold. and so, the best quality and the effect of productivity improvement can be obtained.

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Performance Analysis of New Working Solution for Absorption Refrigeration Machine using Treated Sewage (하수처리수이용 신용액 흡수식 냉동기의 성능해석)

  • 권오경;유선일;윤정인
    • Journal of Energy Engineering
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    • v.7 no.2
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    • pp.231-240
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    • 1998
  • The global environmental problems such as CFC, energy losses in heat recovery system as well as summer peak time power demands, the development of high efficiency absorption refrigeration systems is one of the most promising method in this problems. The absorption refrigeration system to utilize treated sewage is available for environmental protection and energy conservation. Simulation analysis on the double-effect absorption refrigeration cucles with parallel or series flow type has been performed. LiBr+LiI+LiCl+LiNO$_3$ solution was selected as the new working fluid. The main purpose of this study is evaluating the possibilities of effective utilization of treated sewage as a cooling water for the absorber and condenser. The other purpose of the present study is to determine the optimum designs and operating conditions based on the operating constraints and the coefficient of performance in the parallel or series flow type. In this study, we found out the characteristic of new working solution through the cycle simulation and compared LiBr solution to evaluate. The absorption refrigeration machine using the new working fluid was obtained better results COP rise and compactness of system by comparison with LiBr solution.

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A study on the pulse boiling occurring inside the liquid pool of a closed two-phase thermosyphon (밀폐형 2상 열사이폰의 Pool 내부 Pulse Boiling에 관한 연구)

  • Kim, Cheol-Ju;Mun, Seok-Hwan;Gang, Hwan-Guk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.10
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    • pp.1254-1261
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    • 1997
  • Pulse boiling, the unsteady periodic boiling phenomenon appearing in the evaporator of thermosyphons was investigated by many researchers. In the present study investigations were conducted to examine the evolution of flow patterns at the evaporator, and changes in thermodynamic state that each of liquid pool and vapor experiences through 1 cycle of pulse boiling process. For wall and liquid pool the degree of superheat for the onset of nucleation was examined. It revealed that the degree of superheat increased with the increase of pulse period, reaching to 16.5 deg.C and 23 deg.C for liquid pool and evaporator wall respectively at .tau.=80 sec. The data on flow patterns obtained through series of operation tests were plotted in the coordinates of heat flux and vapor pressure to get a regime map. Further this map could be used to figure out the conditions of pulse boiling for a thermosyphon.