• Title/Summary/Keyword: pattern transfer

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A Numerical Study of the Turbulent Flow Characteristics in the Inlet Transition Square Duct Based on Roof Configuration (4각 안내덕트 루프형상에 의한 난류특성변화 수치해석)

  • Yoo, Geun-Jong;Choi, Hoon-Ki;Choi, Kee-Lim;Shin, Byeong-Ju
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.7
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    • pp.541-551
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    • 2009
  • Configuration of the inlet transition square duct (hereinafter referred to as "transition duct") for heat recovery steam generator (hereinafter referred to as "HRSG") in combined cycle power plant is limited by the construction type of HRSG and plant site condition. The main purpose of the present study is to analyze the effect of a variation in turbulent flow pattern by roof slop angle change of transition duct for horizontal HRSG, which is influencing heat flux in heat transfer structure to the finned tube bank. In this study, a computational fluid dynamics(CFD) is applied to predict turbulent flow pattern and comparisons are made to 1/12th scale cold model test data for verification. Re-normalization group theory (RNG) based k-$\epsilon$ turbulent model, which improves the accuracy for rapidly strained flow and swirling flow in comparison with standard k-$\epsilon$ model, is used for the results cited in this study. To reduce the amount of computer resources required for modeling the finned tube bank, a porous media model is used.

A Study on the Load Carrying Capacity and Equivalence Friction Coefficient of a Textured Plane Bearing with Semi-spherical Dimples and Semi-ellipsoidal Dimples (반구형 및 반타원형으로 텍스처링된 평면 베어링의 부하지지능력과 등가마찰계수에 대한 해석)

  • Lee, Soo-Young;Kim, Pil-Kee;Seok, Jong-Hyuk;Seok, Jong-Won
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.5
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    • pp.741-746
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    • 2012
  • The increase of energetic efficiency in plane bearing is getting more important in the transfer mechanism of semi-conductor and display panel manufacturing processes. To accomplish this objective, the technique of surface texturing on bearing surface has recently emerged as one of the most effective candidates. In this study, the effects of various pattern parameters on two bearing performance indices(load carrying capacity and effective friction coefficient) are investigated through a semi-analytic method, i.e., the 2-dimensional Reynolds equation incorporated into the finite difference scheme. Here, cavitation effect is also taken into account by employing an appropriate numerical scheme. In this study, the patterns in the textured surface are composed of a series of semi-spheres or semi-ellipsoids in shape. The effects of their size and number density on the performance indices are examined through the performance of various numerical experiments. Also, the effects of the anisotropy of the semi-ellipsoidal pattern on the bearing's lubrication characteristics are investigated and discussed.

10㎛-wide Pattern Engraving using Metal Specimens coated with a heterogeneous metal for Printed Electronics (이종 금속이 코팅된 금속소재를 이용한 인쇄전자소자용 선폭 10㎛급 패턴 가공)

  • Sohn, Hyonkee;Cao, Binh Xuan;Cho, Yong-Kwon;Shin, Dong-Sig;Choi, Jiyeon
    • Laser Solutions
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    • v.17 no.4
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    • pp.20-23
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    • 2014
  • In printed electronics, printing rolls are used to transfer electronic ink onto a flexible substrate. Generally printing rolls are patterned in microscale by the indirect laser method. Since based on the wet etch process, the indirect method is neither environment-friendly nor suitable for making a printing roll with patterns narrower than $20{\mu}m$. In this paper, we have directly engraved micro-patterns into a Zn-coated metal specimens using a picosecond laser in order both to engrave $10{\mu}m$-wide patterns and to improve the pattern profile. Experiments showed that it is possible to engrave $10{\mu}m$-wide patterns with an a rectangular-shaped profile which is necessary for the dimensionally accurate printing.

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The Comparative Study of the Warranty Cost Model for Software Reliability Time Based on Extreme Value Distribution (극값 분포 특성을 가진 소프트웨어 신뢰성 보증 모형에 관한 비교연구)

  • Kim, Hee-Cheul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.6B
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    • pp.623-629
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    • 2009
  • In this research, the process of developing software products to users in transfer by considering the warranty period to determine the timing of the release period is a comparative study of models. For the results of demonstration, exponential software reliability model increases the warranty period, the higher the initial period, but shows almost a similar release. In contrast, the optimal release time of imperfect debugging software reliability model, lower the initial warranty period, but the pattern is expected to rise slightly larger. The proposed model, extreme value distribution model, pattern of the optimal release time gradually increase, have a form that can be drawn. These research results through, warranty period and release the software developers understand the relationship between the optimal time for software development by using advance information could do is feed.

A Study on Home Health Care Service and the Level of Client Satisfaction (가정간호 서비스내용 및 만족도에 대한 조사연구)

  • Jo, Mi-Ja;Hyun, Hye-Jin;Yun, Soon-Nyoung
    • Journal of Home Health Care Nursing
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    • v.2
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    • pp.52-59
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    • 1995
  • This Study was done to examine the home health care service provided by home care nurses and the level of client satisfaction. Data were collected from 60 clients who received services from a home care center. The tool for measurement of satisfaction was composed 13 items and was 3 score scale. The results of this study are summarized as follows ; 1. By the disease pattern, subjects were distributed into cardiovascuvr disease(73.5%), digestire disease(10.2%), endocrine disease (6.1%), Senile dementia(6.1%) and the others(4.0%). 2. By the disease pattern, provided home health care services were follows; In cardiovascular disease and digestire disease, direct nursing service, education and physical assessment were provided every time. In senile dementia, direct nursing services were mainly provided and transfer and medication were rarely provided. 3. The level of satisfaction on provided home health services was high; mean score was 2.4 out of 3.

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Numerical Investigation on Load Supporting Mechanism of a Pile Constructed above Underground Cavity (공동이 존재하는 암반에 시공된 말뚝기초의 하중지지 메카니즘에 관한 수치해석 연구)

  • Choi, Go-Ny;Yoo, Chung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.27 no.1
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    • pp.5-16
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    • 2011
  • This paper presents the results of a three-dimensional finite element analysis on load supporting mechanism of pile constructed above underground cavity in limestone rock formation. Considering a wide range of cavity conditions, the behavior of pile was studied using the bearing capacity, rock yielding pattern, stress distribution and deformation of pile head and the cavity. The results indicate that the load transfer mechanism of pile, rock yielding pattern and the reduction of bearing capacity of pile significantly vary with the location, size and length of cavity. Based on the results, graphical solutions defining the reduction of the bearing capacity with specific cavity conditions were suggested.

The Research about a Control Data Duplication Transmission Technique (제어데이터 중복전송기법에 관한 연구)

  • Lee, Young-Ju;Kang, Soon-Duk
    • The Journal of Information Technology
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    • v.9 no.4
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    • pp.57-63
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    • 2006
  • The intelligent elder brother groove network robot service the new broadband presence line is conversionce application service. Robot control data transmission hazard UDP packet of the remote control data which stands duplication necessary to transmit. TCP the error ratio to be high qualitative recording transmission pattern it of the transmission unit and is irregular the distance is distant to show and also the transmission lag is visible increases. The recording packet drop whose UDP degree error ratio will be high is frequent and does not arrive packet little by little increases is a possibility of knowing in the transmission unit. The technique which it proposes with traffic pattern of the transmission unit is visible the transfer characteristic of the same shape from 1% packet error ratio degree. The effective transmission technique of the robot control data which puts a base in UDP protocols was proposed from the present paper. Following research it leads and it follows the duplication transmission number of time in error rate of radio link and it was thought all that controls petty the research of the mechanism which progresses is necessary.

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STUDY ON THE KOREAN UNIVERSITY LIBRARIES FROM 1924-1945 (우리나라 대학도서관(大学図書館)에 관(関)한 고찰(考察) -1924년(年)~1941년대(年代)를 중심(中心)으로-)

  • Yoon, Seung-Hyeon
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.5 no.1
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    • pp.133-164
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    • 1981
  • "Jonkyongkak" which King, Sungjong of Yi dynasty established within Sungkyunkwan in 1475 is regarded as the first university library in Korea. On the basis of modern librarianship, however, it is desirable to recognize the fact that Keijo Imperial University Library is really the first university library in Korea. In this thesis, an attempt to study the Korean university libraries under the period of Japanese control is provided. Keijo Imperial University Library is the key institution in this study. This study will focus to review the following facts: 1) the historical background of Keijo. Imperial University Library; 2) the organization and staffing pattern, and budget of this library; 3) the acquisition policy and basic collection development plan of this library; 4) the library and other services of this library including readers services; 5) the relationship with other private college libraries; and 6) the impact of this library on the present Seoul National University Library. The followings are the outlined conclusions: 1. Japanese Government had established Keijo Imperial University Library in order to perform the colonial education policy of Korean peninsula. Furthermore, it was one of the import supporting agencies for the research activities which were necessary for Japan to govern the Southeast Asia including Korean Peninsula 2. The organization and staffing size and pattern of this library are much below to those of modern university libraries. They are somewhat below to the level which is necessary to perform the minimum basic library functions. 3. The priorities of book collection of this library are 1) humanities and social sciences especially, materials on Law are much emphasized; 2) pure sciences and 3) technologies and agriculture. Therefore, the quantity of the materials on the field of technology and agriculture is very small. 4. The acquisition policies of this library are deeply influenced by the Japanese Government's colonial policy of Korean peninsula and her aggressive policy of Chinese Continent. 5. The major contribution of this library to the present Seoul National University Library is the transfer of 550,000 volumes of books and library building, but this building is now removed according to the transfer of Seoul National University Campus. 6. The staffing pattern of this library was, however, much ahead of that times. Especially, the facts that professional librarians were eligible to be appointed as the director of this library, and they had the faculty membership including faculty rank should be highly appreciated.

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Specific Localization of DNMT1 in Mouse and Bovine Preimplantation Embryos

  • Y.M.Chang;Min, K.S.;Yoon, J.T.;M.G.Pang;Chung, Y.C.;Kim, C.K.
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.81-81
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    • 2003
  • DNA methylation is a covalent modification of DNA that can modulate gene expression and is now recognized as a major component of the epigenome. During evolution, the dinucleotide CpG has been progressively eliminated from the genome of higher eukaryotes and is present at only 5% to 10% of its predicted frequency. Approxymately 80% of the remaining CpG sites contain methylated cytosines in most vertebrates and they are distributed in a pattern that is unique in each tissue and is inversely correlated with gene expression. The pattern of methylation is faithfully maintained during cell division by the enzyme Dnmt1, the maintenance DNA methyltransferase, which catalyzes the transfer of a methyl group from S-adenosyl-methionine to the 5'-position of the cytosine ring. We have been identified bovine Dnmt1 cDNA full-length recently (AY173048) Little is known on the functions of Dnmt1 in bovine preimplantation embryos. Thus, we analyzed the specific pattern of Dnmt1 in in vitro derived/nuclear transfer bovine and in vivo derived mouse embryos to monitor the epigenetic reprogramming process. We investigated these process by using indirect immunofluresence with an antibody to Dnmt1. According to other studies, Dnmt1 accumulates in nuclei of early growing oocytes but is sequestered in the cytoplasm of mature oocytes. In 2-cell and 4-cell embryos, Dnmt1 is cytoplasmic, but at the 8-cell stage, it is present only in the nucleus. By the blastocyst stage, Dnmt1o is again found only in the cytoplasm. Thus, nuclear localization of Dnmt1o in preimplantation embryos is limited to the 8-cell stages After implantation, Dnmt1 is localized in the nucleus in mouse. However, we have found different patterns of Dnmt1 nuclear localization. Though we used the common antibody, immune-localization data revealed that Dnmt1 antibody have been detected at the nucleus in 1-cell to blastocyst embryos. Therefore, maybe we think that the functions of Dnmt1 between bovine and mice are different. In order to Identify the mechanisms that regulate DNA methylation in bovine preimplantation embryo, we have plans on using bovine oocyte and somatic specific Dnmt1 antibodies.

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Analysis and Design of Planar Textile Resonator for Wearable Magnetic Resonance-Wireless Power Transfer (의복용 자기공진형 무선전력전송 시스템을 위한 평면형 직물공진기의 설계 및 연구)

  • Kang, Seok Hyon;Jung, Chang Won
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.8
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    • pp.119-126
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    • 2016
  • In this paper, we proposed the planar textile resonator for constructing wearable MR-WPT system and analyzed the characteristic of textile substrates used in resonators. The planar textile resonators were designed to resonate at 1-10 MHz. The loop and coil were fabricated planar structure on textile substrate using conductive materials. Polyester fiber and cotton widely used in real life were chosen as textile resonators for wearable applications and copper tape and silver paste were used for fabricating planar loop and coil on textile substrate. For comparison analysis on transfer efficiency according to the types of textile, transmitter and receiver parts were symmetric. According to the result, for the highest transfer efficiency of wearable WPT system, the planar resonators have specifications of relative thick textile substrate with low permittivity and low surface resistance of conductive pattern. The performed experiments show that the planar textile resonator is possible to be used for resonator in wearable MR-WPT system.