• Title/Summary/Keyword: general transfer effect

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Effect of Relative Position of Vane and Blade on Heat/Mass Transfer Characteristics on Stationary Turbine Blade Surface (베인과 블레이드 사이의 상대위치 변화에 따른 터빈 블레이드 표면에서의 열/물질전달 특성)

  • Rhee, Dong-Ho;Cho, Hyung Hee
    • The KSFM Journal of Fluid Machinery
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    • v.8 no.4 s.31
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    • pp.27-38
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    • 2005
  • The present study investigated the effect of relative position of the blade on blade surface heat transfer. The experiments were conducted in a low speed wind tunnel with a stationary annular turbine cascade. The test section has a single turbine stage composed of sixteen guide vanes and blades. The chord length of the blade is 150 mm and the mean tip clearance of the blade is $2.5\%$ of the blade chord. The Reynolds number based on blade inlet velocity and chord length is $1.5{\times}105$ and mean turbulence intensity is about $3\%$. To investigate the effect of relative position of blade, the blade at six different positions in a pitch was examined. For the detailed mass transfer measurements, a naphthalene sublimation technique was used. In general, complex heat transfer characteristics are observed on the blade surface due to various flow characteristics, such as a laminar flow separation, relaminarization, flow acceleration, transition to turbulence and tip leakage vortices. The results show that the blade relative position affects those heat transfer characteristics because the distributions of incoming flow velocity and turbulence intensity are changed. Especially, the heat transfer pattern on the near-tip region is significantly affected by the relative position of the blade because the effect of tip leakage vortex is strongly dependent on the blade position. On the pressure side, the effect of blade position is not so significant as on the suction side surface although the position and the size of the separation bubble are changed.

Mass transfer characteristics of continuous electrocoagulation for dyestuff solution using aluminum flat plate electrode (Al 전극에 의한 염료의 전기응집에서 물질전달 특성)

  • Kim, Tak-Hyun;Park, Chulhwan;Shin, Eung-Bai;Kim, Sangyong
    • Proceedings of the KAIS Fall Conference
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    • 2001.05a
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    • pp.290-291
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    • 2001
  • The relationship between velocity, viscosity, diffusion coefficient, mass transfer coefficient and characteristic length and mass transfer data can be correlated by dimensionless relationship in electrolytic process. The performance of dyestuff removal was decreased as the flow rate of electrolyte was increased. It was due to the effect of retention time decreasing was superior to that of turbulent inlet mixing. Sh/Sc$\^$1/3/ vs Re plot for Al flat electrode did not showed the general tendency of the relationship between Sh/Sc$\^$1/3/ and Re. It can be thought that flow rate was not sufficiently high to increase the effect of mixing.

Vibration Transfer Characteristic of Seat with the Auxiliary Plastic Member for Movie Theater Chair (플라스틱 보조재를 갖는 영화관 의자 시트의 진동전달 특성)

  • Kang, Hwa-Joong;Kim, Tae-Gyun;Moon, Deok-Hong
    • Journal of Power System Engineering
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    • v.18 no.6
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    • pp.45-50
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    • 2014
  • In the previous paper, we have reported on the development of foaming sponge seat with the auxiliary spring member and suggested new possibility of the special seat with the auxiliary plastic member for movie theater chair. In this study, we have examined the major design parameters needed in the development of a foaming sponge seat in which the mesh type plastic member are inserted to improve the vibration transfer effect of a chair seat. Through analyzing several prototypes by applying experimentation as well as the experimental modal analysis method, it was confirmed that the effect of vibration transfer can be improved through the use of a mesh type plastic member and applied to the design of practical chair seat.

Development of Vibroacoustic Stimulation Seat for a Movie Theater Chair (영화관 의자용 음향진동자극 시트의 개발)

  • Moon, Deok-Hong
    • Journal of Power System Engineering
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    • v.17 no.1
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    • pp.42-49
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    • 2013
  • The global movie industry is continuing rapid growth through application of the latest technology. 3D movies are being produced and shown for a more effective viewing experience. Special chairs for audiences are being experimentally manufactured and installed for the greatest viewing effect. This special chair has a structure that applies vibrating stimuli to specific parts of the body by attaching vibration transducers to theater chairs and synchronizing it with each scene of the movie. In a previous study, it has been confirmed that we can analyze the vibration transfer characteristics of sponge seats through the application of an experimental modal analysis method and obtain design variables easily. In this paper, we examine the major design parameters needed in the development of a foaming sponge seat in which auxiliary springs are inserted to improve the vibration transfer effect of a chair seat. Through analyzing several prototypes by applying experimentation as well as the experimental modal analysis method, it was confirmed that the effect of vibration transfer can be improved through the use of an auxiliary member.

A Study on the Seller's Liability regarding Property in Goods on the International Sale of Goods

  • Oh, Won-Suk;Min, Joo-Hee
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.52
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    • pp.3-22
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    • 2011
  • This study examines the seller's liability to transfer the property to the buyer. Even though contracting parties choose CISG as the governing law regulating their obligations and rights by means of their contract, CISG does not concern with the effect generated by the transfer of property. Thus, the issues of the property is settled in conformity with the domestic law applicable by virtue of the rules of private international law. By considering the general rules of the transfer of property in goods under SGA and KCC as the lex rei sitae, the difference of requirements to pass the property between them is analyzed and then the reasons why the transfer of property is importantly considered are discussed. In addition, as CISG does not exclude completely the matters concerning the property and provides the provision like Art 41, the seller's liability to deliver goods free from the third party right or claim is examined under Art 41. Lastly, the practical advice is suggested.

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Shear Load Transfer Characteristics of Drilled Shafts in Weathered Rocks (풍화암에 근입된 현장타설 말뚝의 하중 전이 특성)

  • Jeong, Sang-Seom;Cho, Sung-Han;Kim, Soo-Il
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03a
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    • pp.85-106
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    • 2000
  • The load distribution and deformation of drilled shafts subjected to axial loads were evaluated by a load transfer approach. The emphasis was on quantifying the load transfer mechanism at the interface between the shafts and surrounding highly weathered rocks based on a numerical analysis and small-scale tension load tests performed on nine instrumented piles. An analytical method that takes into account the soil coupling effect was developed using a modified Mindlin's point load solution. Based on the analysis, a single-modified hyperbolic model is proposed for the shear transfer function of drilled shafts in highly weathered rocks. Through comparisons with field case studies, it is found that the prediction by the present approach is in good agreement with the general trend observed by in-situ measurements.

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Effect of Boundary Layer Generated on the fin surfaces of a Compact Heat Exchanger on the Heat Transfer and Pressure Drop Characteristics (컴팩트형 열교환기의 핀 표면에서 발생하는 경계층이 열교환기의 전열 및 압력강하 특성의 변화에 미치는 영향에 관한 수치해석적 연구)

  • KIM Chul-Ho;Jung Ji-Yong
    • Journal of computational fluids engineering
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    • v.3 no.1
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    • pp.82-88
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    • 1998
  • As a par of a project related to the development of the design algorithm of a compact heat exchanger for the application of the electronic home appliances, the effect of the discreteness of the airflow boundary generated on the cooling fin surface on the heat transfer and pressure drop characteristics of the heat exchanger was studied numerically. In general, there are two critical design parameters seriously considered in the design of the heat exchanger; heat transfer rate(Q) and pressure drop coefficient(C/sub p/). Even though the higher heat transfer rate with lower pressure drop characteristics is required in a design of the heat exchanger, it is not an easy job to satisfy both conditions at the same time because these two parameters are phenomenally inversely proportional. To control the boundary layer thickness and its length along the streamline, the surface of the flat fin was modified to accelerate the heat transfer rate on the fin surface. To understand the effect of the discreted fin size(S/sub w/) and its location(S/sub h/) on the performance of the heat exchanger in the airflow field, the flat fin was modified as shown in Fig. 1. From this study, it was found that the smaller and more number of slits on the fin surface showed the higher energy diffusion rate. It means that the discreteness of the boundary layer is quite important on the heat transfer rate of the heat exchanger. On the other hand, if the fin surface configuration is very complex than needed, higher static pressure drop occurs than required in a system and it may be a reason of the induced aerodynamic noise in the heat exchanger.

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Experimental study of air side pressure drop and heat transfer characteristics of wave and wave-slit fin-tube heat exchangers (웨이브 및 웨이브-슬릿 열전달촉진 휜-관 열교환기의 공기측 압력강하 및 열전달 특성에 관한 실험)

  • Yoon, Baek;Gil, Yong-Hyun;Park, Hyun-Yeon;Yoo, Guk-Chul;Kim, Young-Saeng
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.5
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    • pp.589-599
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    • 1998
  • Air side heat transfer and pressure drop for fin-tube heat exchanger with wave and wave-slit fins were measured for various fin spacings and number of tube rows. Outer diameter of the tube including fin collar is 10.07mm, and experiments were done with dry surface condition. Longitudinal and transverse tube spacings of the heat exchangers are 21.65mm and 25mm respectively, and wave depth of the wave fin is 2mm. Experiments were conducted for 1, 2 and 3 rows and 3 different fin spacings, 1.3, 1.5 and 1.7mm. An attempt was made to demonstrate advantage of the enhanced fins over the plane fin by introducing the concept of fan power, Effect of the number of tube rows on heat transfer was discussed in connection with general mechanisms of heat transfer enhancement for fin-tube heat exchanger. Also the effect of hydrophilic coating was investigated. Lastly, correlations for Colburn j-factor and friction factor were developed.

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Evaluation of Diaphragm Effect for Hybrid Structural Systems Using Finite Element Method (유한요소법을 이용한 주상복합건물의 강막작용에 의한 영향 평가)

  • 김희철;최성우;홍원기
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.16 no.1
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    • pp.19-32
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    • 2003
  • The structural system of a hybrid building is composed of upper shear wall which resist lateral force by bending deformation and lower frame which resist lateral force by shear deformation. A deep transfer girder is used to transfer gravity load safely from super structures to structural frame beneath. Because of the vertical discontinuity, a building with transfer girder must be analyzed by dynamic analysis. However, this structural system has many problems in performing dynamic analysis that cannot be solved by general analysis procedure. The slabs In transfer floor are considered as either a Plate element or a rigid diaphragm in finite element analysis without appropriate evaluation of their characteristics. Therefore, a reasonable analysis method is proposed in this study by evaluating the diaphragm effect of a hybrid structure system.

The Interaction between Epidermal Growth Factor (EGF) and Follicular Stimulating Hormone (FSH) on Nuclear Maturation of Mouse Oocytes by Using Their Inhibitor

  • Cha, Soo-Kyung;Kim, Tae-Hyung;Eum, Jin-Hee;Park, Kang-Hee;Park, Eun-A;Kim, Seung-Bum;Chung, Mi-Kyung;Lee, Dong-Ryul;Ko, Jung-Jae
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.113-113
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    • 2002
  • The stimulatory effect of EGF and FSH on oocyte maturation have been reported in various mammalian species. And some reports presented FSH enhanced the effect of EGF on oocyte maturation. But, the interaction between EGF and FSH on nuclear maturation of mammalian oocytes is not fully understood. We observed the effect of EGF and FSH on nuclear maturation during in vitro maturation of mouse oocytes. Also, we examined the interaction between EGF and FSH on nuclear maturation of mouse oocytes using the EGFR inhibitor or FSH inhibitor. Germinal vesicle (GV) stage oocytes were obtained from 3-4weeks PMSG primed BCFI hybrid mice and cultured in TCM-199 medium with 0.4%PVP supplemented with/without EGF (1ng/ml), FSH (1ug/ml), EGFR specific tyrosine kinase inhibitors: Tyrphostin AG 1478 (500nM), MAP kinase kinase inhibitor : U0126 (20uM) or PD 98059 (100uM) for 14-l5hr. Rapid staining method were used for the assessment of nuclear maturation. Nuclear maturation rates of EGF indjor FSH-treated group were significantly higher than those of control group. Treatment of EGFR inhibitor significantly block the nuclear maturation of GV oocyte in EGF-treated group, but it did not block those of GV oocyte in FSH-treated or FSH and EGF-treated group. Treatment of FSH inhibitor(U0126, PD98059) significantly block the nuclear maturation of EGF-treated group, FSH-treated and FSH and EGF-treated group. These results show that EGF has a stimulatory effect as well as different action pathway with FSH on in-vitro maturation of mouse oocyte in vitro. Therefore, further studies will be needed to find the signaling pathway of EGF associated with nuclear maturation.

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