• Title/Summary/Keyword: In-kind Transfer

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Basic Electrical & Electronic Technology Transfer in High Speed Rail (고속전철의 전기.전자(電氣.電子)분야 기술이전(技術移轉) 전략)

  • Wee, Sang-Bong
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.547-549
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    • 1994
  • This paper reports the importance of basic electrical and electronic technology transfer compatible with domestic environment. At first, several kind of problems in technology transfer was issued in view of domestic environment. For example, the differences between France & Korea were illustrated in power system, signalling, electronics including computer system. And then technology tree was showed based on technology transfer strategy.

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Effects of Oil and Internally Finned Tubes on the Performance of the Air-Conditioning Unit (전열관 형상과 냉동기유 효과를 고려한 공조기기의 성능예측)

  • Yun, J.Y.;Lee, K.S.;Lee, D.J.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.6 no.4
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    • pp.388-398
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    • 1994
  • Computer simulation model for predicting more accurately the heat transfer performance of the evaporator and condenser which have significantly affected on the performance of air-conditioner has been suggested. In this model oil and micro-fin tube used in a actual unit are considered to simulate the more realistic case. The effects of oil and micro-fin tube on the performance of an air-conditioner have been investigated. It is found that the present model requires higher pressure than the existing model due to the characteristics of the tube considered. However, it turns out that the present model is very close to an actual cycle. As the amount of oil inside the tube increases, condensation heat transfer coefficient shows a linear decrease irrespective of a kind of oil, while evaporation heat transfer coefficient increases slightly in the oil with low viscosity and decreases exponentially in the oil with high viscosity. Pressure drop in both evaporator and condenser increases linearly irrespective of a kind of oil. It is also found that the effect of the variation of oil concentration on the magnitude of two-phase region is negligible.

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Study on the characteristics of nucleate boiling heat transfer with changing of surface roughness (표면거칠기의 변화에 따른 핵비등열전달의 특성에 관한 연구)

  • 김춘식;정대인;배종욱
    • Journal of Advanced Marine Engineering and Technology
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    • v.7 no.1
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    • pp.64-78
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    • 1983
  • In nucleate boiling, bubbles are created by the expansion of entrapped gas or vapor at small cavities in the surface of heat transfer. Namely, surface roughness is the important factor of heat transfer. This paper deals with the characteristics of boiling curve according to surface roughness. Freon-113 is used as the experimental fluid. The results are as follows; 1. In the case of the same as "q=C$\Delta$T$^{n}$ ", the lower numberical index "n", the larger heat transfer coefficient and the lower wall superheat "$\Delta$T" is obtained for the rougher surface. 2. In the working of every kind of heat transfer sruface with boiling, improvement of capabilities of heat transfer can be devised by adding suitable roughness on the heat transfer surface. 3. When the metal nets of moderate mesh number are established, the capabilities of heat transfer can be improved in evaporation of liquid in vessels. But in the case that the sucession of bubbles in checked by using the nets which are too tight, the generation of bubbles union decreases critical heat flux. decreases critical heat flux.

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Measurement of Mechanical-acoustic Transfer Functions of Vehicles by Combination of Mechanical and Acoustic Excitations (구조가진과 음향 가진의 결합에 의한 차량의 구조-음향 전달 함수 측정)

  • 고강호;이장무
    • Transactions of the Korean Society of Automotive Engineers
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    • v.7 no.9
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    • pp.158-164
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    • 1999
  • In this paper a simple measurement technique for mechanical-acoustic transfer functions is proposed . The mechanical-acoustic transfer functions, generally , are measured through mechanical excitations ; impact hammers or shakers. Recently , by virtue of vibro-acoustical reciprocity principle, they are measured through acoustic excitations : loudspeakers. This kind of test needs to measure the volume velocity , the radiation characteristics of a sound source. Because the volume velocity of the sound source is changed by driving signal , it is difficult to measure it. However , the new method in this paper needs not to measure the volume velocity of a sound source by combination of mechanical and acoustic excitations. Moreover, this method has the methodological advantages, such as usage of a general loudspeaker for the reciprocal excitation, no sptatial limitations for measurements of mechanical-acoustic transfer functions.

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The effects of nanofluid containing metal nano-powder on heat transfer (나노금속분말을 혼합한 용액이 열전달에 미치는 영향)

  • Kim, Hye-Min;Choi, Soon-Ho;Jeong, Jae-Hyun;Jeong, Jae-Hyun
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.177-182
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    • 2005
  • Many studies have been conducted to increase heat transfer in fluid. One of the various heat transfer enhancement techniques is to suspend fine metallic or nonmetallic solid powder in traditional fluid. Nanofluid is defined at a new kind of heat transfer fluid containing a very small quantity of nanometer particles that are uniformly and stably suspended in a liquid. In this study CuNi or CuAg nano particles are used to investigate heat transfer enhancement. The result shows the thermal conductivity of nanofluid is much higher than that of traditional fluid.

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Investigation into circulation of ground water by air sparging (Air sparging에 의한 지하수 순환에 관한 연구)

  • 이준희;강구영
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1998.11a
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    • pp.232-235
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    • 1998
  • Air sparging system is a kind of in-situ bioremediation method in the contaminated ground water. When Air sparging, the both of water circulation and oxygen transfer happend in the same time. The hydraulic differential head is zero at the middle height of well, is negative below the height and is possitive above the height. Hydroraulic head gradient is proportioned to air superficial velocity in the well. But over 24m/min of the superficial velocity, the hydraulic head gradient increase little.

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Convective heat transfer on the rotor fan and endring of the TEFC induction motor with telemetry system (무선계측기를 이용한 회전자팬 및 엔드링에서의 대류 열전달)

  • Yun, Myeong-Geun;Ha, Gyeong-Pyo;Go, Sang-Geun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.4
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    • pp.510-519
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    • 1998
  • Recently, computer modelling is increasingly used as a design tool, which requires more detailed data for heat transfer coefficients in various regions of the induction motor. But there are little information about those of rotor fan and endring because of difficulty in measuring signals in rotating bodies. In the present studies, the temperature signals were precisely measured with self-developed telemetry system, which had multi-channels and high rotational speed. After some losses were compensated, the heat transfer coefficients of the rotor endring and fan surfaces were measured. Minimum heat transfer region was existed with endcap plate distance and maximum heat transfer was found at some rotor fan width. It was also studied that how the guide plate and endcap inside rib effected on the rotor heat transfer. The higher heat transfer were obtained with decreasing guide plate distance, increasing the number and height of endcap inside rib. The correlation equations of the results were obtained and compared with others. Above results of the heat transfer coefficients can be used as basic data for cooling design of the various kind of motors.

Classification of Bridge Current and Analysis of Heat Transfer Characteristics in Polyvinyl-Chloride-Sheathed Flat Cord Under Tracking

  • Jee, Seung-Wook;Lee, Chun-Ha;Lee, Kwang-Sik
    • Journal of Electrical Engineering and Technology
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    • v.8 no.1
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    • pp.176-182
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    • 2013
  • In this study, we examine the tracking happen in a polyvinyl-chloride-sheathed flat cord (PVCSFC), which is widely used as a distribution cord. The study classifies the bridge current via the formed conductive paths during tracking in the PVCSFC. Further, it attempts to distinguish the characteristics of heat generation and heat transfer by kind of bridge current. When the PVCSFC is in the static state, the bridge currents flow only through the electrolyte bridge. In the case of the carbonized PVCSFC, the bridge currents flow through one or more conductive paths. One is the electrolyte bridge, the other is the bridge that is consisted electrolyte and carbonized insulation. Currents flowing through different conductive paths have different heat generation and transfer characteristics. As the bridge current flowing in the conductive path consisting of electrolyte and carbonized insulation increases, the temperature difference between the surface of the PVCSFC and ambient air also increases correspondingly.

Anti-Sway System for Automated Transfer Crane (자동 트랜스퍼 크레인을 위한 컨테이너 흔들림 장치)

  • 박찬훈;박경택;김두형
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1743-1746
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    • 2003
  • Automated Container Terminals have been being developed over the world for many recent years and more and more countries get interested in it because the amount of containers exported or imported is steeply increasing. Existed Container Terminals were not designed to control this kind of heavily many containers. They would face many structural problems soon or later, although they have managed to do well until now. One of the most important things in developing Automated Container Terminal is to develop the equipment able to transfer the awfully many containers. Those are maybe Automated Transfer Cranes, Automated Guided Vehicles, and Automated Quay-Side Cranes. The word "Automated" means the equipment is operated without drivers and those equipments are able to work without taking any break. Through the researches on the existed transfer cranes, authors decided that the structure of existed transfer cranes is not proper to swift and fast transfer and it′s not impossible to handle so many containers in limited time. Therefore authors have been studying on the proper structure of the Automated Container Crane for past several years and a new type of transfer crane has been developed. Design concepts and control methods of a new crane will be introduced in this paper.

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Transfer of Right and Negotiability of the Electronic Bill of Lading in Electronic Trade Transactions (전자무역거래에서 전자식 선화증권의 권리이전과 유통에 관한 고찰)

  • Jo, Sang-Hyeon;Kang, Won-Jin
    • International Commerce and Information Review
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    • v.10 no.2
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    • pp.23-43
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    • 2008
  • Requirement of facilitating electronic trade transactions and efforts to platform on the electronic trade in major countries are link to the interest of Bill of Lading, the major transportation document, to be electronic, namely interest in Electronic Bill of Lading. Regardless of the benefits from replacing paper based Bill of Lading to the electronic form, which are eliminating of the Crisis of Bill of Lading and cost saving of international trade community, it has not been successful so far. Among the three functions of Bill of Lading, evidence of contracts and receipt of goods can be easily transferable to the electronic form. However the most important function, Document of Title, became the hardest work to replicate in electronic form. The purpose of this paper is to clarify what kind of conditions shall be prepared to ensure the transfer of right and negotiability of the Electronic Bill of Lading and propose to ensure the use of electronic bill of lading and its transfer of right and negotiability in the era of the electronic transactions.

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