• Title/Summary/Keyword: Transport functions

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Monthly Wind Stress and Wind Stress Curl Distributions in the Eastern Sea(Japan Sea) (동해상의 월별 바람응력 및 바람응력컬 분포)

  • 김철호;최병호
    • Water for future
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    • v.19 no.3
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    • pp.239-248
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    • 1986
  • Monthly wind stress, wind stress curl and volume transport stream functions are computed in the Eastern Sea(Japan Sea) based upon observed wind and atmospheric pressure data respectively. The presented two results show different distributios on locality and season but as common features the results reveal the northwesterly surface wind stress \ulcorner 새 the monsoon in winter, south to southwesterly wind stress \ulcorner 새 the southerly wind in summer and strond anticyclonic curl in the northern part on the Eastern Sea(Japan Sea) in winter. In the distributions obtained from the sea level atmospheric pressure data, the maximum value of the wind stress and of curls of small scales are shown off the southeast coast of Siberia and northeast coast of Korea. Volume transport distributions obtained from the Sverdrup relationship suggest that the strong northward boundary current can be formed along the northeast coast of Korea in winter and weak southward boundary current in summer.

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The development of computational fluid dynamics tools for thermal expansion type interrupter with the arc rotary (아크회전과 열팽창 방식을 적용한 소호부에 대한 아크유동 해석)

  • Choulkov, Victor;Lee, B.W.;Seo, J.M.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.813-815
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    • 2000
  • This paper is concerned with the development of PC based computer simulation and design tools for auto-expansion SF6 circuit breaker with the arc rotary. The simulation model takes into account radiation transport, turbulence enhanced momentum. energy transport. The conversation gas dynamic equation together with Maxwells equations are solved. For the arc simulation the straightforward procedure has been used. The temperature, gas density and velocity space distributions within the circuit breaker are simulated in details. The presented results show that the computer simulation of gas flow in SF6 interrupter is a subject of much interest for design and optimization of contacts. The presented results show that the shape and sizes of contacts are chosen by this tool from judiciously compromise between electrical breakdown strength and interruption ability that are functions of gas flow parameters.

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Parts Processing Route and Economic Design in Flexible Manufacturing Systems employing AGVs for Transport (무인 반송시스템을 이용하는 유연 제조시스템에서 작업경로와 경제적 설계)

  • 장석화
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.46
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    • pp.19-32
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    • 1998
  • This paper addresses the processing route of parts and economic design in flexible manufacturing systems (FMSs) employing AGVs for Transport. Parts are processed through several workstations according to operation sequences. The machine of each workstation can do multiple operation functions. The operation stage of a part can be processed in several workstations, which are non-identical in functional performance. The objective of this paper is to determine the processing route of parts, number of machines at each workstation, number of vehicles. The model is assumed that the operation stage of parts can be processed at the only one among several available workstations. Parts are transported by automated guided vehicle system(AGVS). The decision criteria is to minimize the sum of processing cost, travel cost, operating cost. A model formulation is represented. A solution algorithm is suggested by using mathematical programming and simulation technique, and a numerical example is shown.

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Urine Concentrating Mechanism and Urea Transporters (소변 농축 기전과 요소운반체)

  • Kim Dong-Un
    • Childhood Kidney Diseases
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    • v.9 no.1
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    • pp.1-7
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    • 2005
  • The production of concentrated urine is achieved by countercurrent multiplication in the renal medulla. The single effect of the outer medulla is the active NaCl reabsorption in the thick ascending limb, while the single effect of the inner medulla is the passive efflux of NaCl through the thin ascending limb. The passive mechanism in the inner medulla requires a high interstitial urea concentration which is maintained by intrarenal recycling of urea. During the past decade, many transport proteins involved in the urine concentrating mechanism have been cloned, which has enabled us to understand the countercurrent multiplication mechanism on a molecular basis. This review will summarize the locations and functions of the renal medullary transport proteins, and the recent insights that have been acquired into the long term regulation of urea transporters.

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Therapeutic Potential of Membrane Fatty Acid Modifiaction in Tumor Cells

  • Shon, Yun-Hee;Park, Kun-Young;Kim, Kwang-Soo
    • Preventive Nutrition and Food Science
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    • v.1 no.1
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    • pp.143-150
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    • 1996
  • The membrane fatty acid composition of tumor cell can be modified either in cell by altering the lipid composition of the medium of during growth in animals by changing the dietaty fat composition. These modifications are associated with changes in membrane physical properties and certain cellular functions, including carrier-mediated transport and enzyme contained within the membrane. Such effects influence the transport of nutrients and chemotherapeutic agents in cancer cells .Fatty acid modification also can enhance the sensitivity of the neoplastic cell to chemotherapy. The alteration in plasma membrane composition will be affected through dietary supplementations and the potential value to cancer patients could be a better understanding of the effects of diet on responsiveness of neoplasms to chemotherapy, i.e. cancer patients' chances for a "cure" can be improved by diet changes prior to treatment.

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Study on Subway Emergency System Based on Wireless Sensor Network (무선 센서 네트워크 기반의 지하철 응급 상황 조치 시스템에 관한 연구)

  • Choi, Ho-Jin;Park, Jong-An;Pyun, Jae-Young
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.5
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    • pp.139-146
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    • 2008
  • Wireless sensor network-related application system can perform functions such as environmental pollution monitoring, building control, home automation in future. In this paper, we present wireless sensor network based system for subway station in order to reduce the damage of the people and the subway station due to fire. Sensor nodes in this system can sense temperature, illumination, smoke, and human body in real time and detect the accident in the subway station. These real-time sensing and wireless networking minimize casualties and damage to property.

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A Design Guide to Type-3 PLLs for FMCW Radars (FMCW 레이더용 타입-3 PLL의 설계 가이드)

  • Hwang, In-Duk;Kim, Chang-Hwan
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.4
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    • pp.70-79
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    • 2012
  • A design guide to type-3 PLLs for FMCW radars is provided. To do that, the cross-over frequencies of the open-loop transfer functions were normalized to 1 Hz and closed-loop properties were compared through simulations using Pspice. As a result, several guides to design type-3 PLLs were provided: 1) secure 45 degrees of phase margin, 2) locate two zeroes at an identical frequency, and 3) poles may be added to raise order of the PLL at higher frequencies than the cross-over frequency of the open-loop transfer function about ten times.

Overview of Rosetta for Estimation of Soil Hydraulic Parameters using Support Vector Machines (보조벡터기로를 사용한 토양수리계수 추정을 위한 로제타 개관)

  • Chung, Doug-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.spc
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    • pp.8-13
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    • 2009
  • Mathematical models have become increasingly popular in both research and management problems involving flow and transport processes in the subsurface. Rosetta is a program to estimate unsaturated hydraulic properties from surrogate soil data such as soil texture data and bulk density. Models of this type are called pedotransfer functions (PTFs) as an alternative measurements since they translate basic soil data into hydraulic properties. These functions may be either measured directly or estimated indirectly through prediction from more easily measured data based using quasi-empirical models.

The AP-3 Clathrin-associated Complex Is Essential for Embryonic and Larval Development in Caenorhabditis elegans

  • Shim, Jaegal;Lee, Junho
    • Molecules and Cells
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    • v.19 no.3
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    • pp.452-457
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    • 2005
  • The adaptor protein (AP) complexes are involved in membrane transport of many proteins. There are 3 AP complexes in C. elegans unlike mammals that have four. To study the biological functions of the AP-3 complexes of C. elegans, we sought homologues of the mouse and human genes that encode subunits of the AP-3 complexes by screening C. elegans genomic and EST sequences. We identified single copies of homologues of the ${\mu}3$, ${\sigma}3$, ${\beta}3$ and ${\delta}$ genes. The medium chain of AP-3 is encoded by a single gene in C. elegans but two different genes in mammals. Since there are no known mutations in these genes in C. elegans, we performed RNAi to assess their functions in development. RNAi of each of the genes caused embryonic and larval lethal phenotypes. APM-3 is expressed in most cells, particularly strongly in spermatheca and vulva. We conclude that the products of the C. elegans ${\mu}3$, ${\sigma}3$, ${\beta}3$ and d genes are essential for embryogenesis and larval development.

?Effects of Insamyangwee-Tang on Functions of Stomach and Small Intestine in Experimental Animals (인삼양위탕(人蔘養胃湯)이 위장관(胃腸管)에 미치는 영향(影響))

  • Lee Dong-Hyun;Kim Deog-Gon;Jeong Gyu-Mann
    • The Journal of Pediatrics of Korean Medicine
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    • v.1 no.1
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    • pp.23-37
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    • 1986
  • Although the Insamyangwee-Tang has been widely used in clinical purposes in the oriental medicine and its clinical efficiency is documented for the cases of gastritis, gastric ulcer and enteritis but the experimental study on these has not been undertaken. So,To investigate the clinical efficiency, of Insamyangwee-Tang and validate its oriental medical theory, these experiments were undertaken, by being compared with animal experiment. ?The following results were obtained. ?1. By effect of Insamyangwee-Tang on isolated ileum from mice, rats, rabbits and Guinea pigs, the motility of ileums was inhibited remarkably. ?2. By effect of Insamyangwee-Tang on motility of the small intestine in rabbits, the motility was inhibited remarkably too. ?3. Insamyangwee-Tang inhibited charcoal transport functions in the small intestine of mice. ?4. By effect of Insamyangwee-Tang on isolated duodenum from rats, the motility of duodenum was inhibited remarkably.?5. Gastric juice and pepsin secretion was decreased, anti-ulceration effect was recognized.

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