• Title/Summary/Keyword: Growing process

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Vertically Standing Graphene on Glass Substrate by PECVD

  • Ma, Yifei;Hwang, Wontae;Jang, Haegyu;Chae, Heeyeop
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.232.2-232.2
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    • 2014
  • Since its discovery in 2004, graphene, a sp2-hybridized 2-Dimension carbon material, has drawn enormous attention. A variety of approaches have been attempted, such as epitaxial growth from silicon carbide, chemical reduction of graphene oxide and CVD. Among these approaches, the CVD process takes great attention due to its guarantee of high quality and large scale with high yield on various transition metals. After synthesis of graphene on metal substrate, the subsequent transfer process is needed to transfer graphene onto various target substrates, such as bubbling transfer, renewable epoxy transfer and wet etching transfer. However, those transfer processes are hard to control and inevitably induce defects to graphene film. Especially for wet etching transfer, the metal substrate is totally etched away, which is horrendous resources wasting, time consuming, and unsuitable for industry production. Thus, our group develops one-step process to directly grow graphene on glass substrate in plasma enhanced chemical vapor deposition (PECVD). Copper foil is used as catalyst to enhance the growth of graphene, as well as a temperature shield to provide relatively low temperature to glass substrate. The effect of growth time is reported that longer growth time will provide lower sheet resistance and higher VSG flakes. The VSG with conductivity of $800{\Omega}/sq$ and thickness of 270 nm grown on glass substrate can be obtained under 12 min growing time. The morphology is clearly showed by SEM image and Raman spectra that VSG film is composed of base layer of amorphous carbon and vertically arranged graphene flakes.

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Mechanical and Forming Characteristics of High-Strength Boron-Alloyed Steel with Hot Forming (핫 포밍을 이용한 고강도 보론 첨가 강의 기계적 및 성형 특성 평가)

  • Chae, M.S.;Lee, G.D.;Suh, Y.S.;Lee, K.H.;Kim, Y.S.
    • Transactions of Materials Processing
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    • v.18 no.3
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    • pp.236-244
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    • 2009
  • In response to growing environmental and collision-safety concerns, the automotive industry has gradually used high-strength and ultla-high-strength steels to reduce the weight of automobiles. In order to overcome inherent process disadvantages of these materials such as poor formability and high springback at room temperature, hot forming has recently been developed and adopted to produce some important structural parts in automobiles. This method enables manufacturing of components with complex geometric shapes with minimal springback. In addition, a quenching process may enhance the material strength by more than two times. This paper investigates mechanical and forming characteristics of high-strength boron-alloyed steel with hot forming, in terms of hardness, microstructure, residual stress, and springback. In order to compare with experimental results, a finite element analysis of hot forming process coupled with phase transformation and heat transfer was carried out using DEFORM-3D V6.1 and also, to predict high temperature mechanical properties and flow curves for different phases, a material properties modeler, JMatPro was used.

Evolutional Process of Economic Integration In The U. S. Broiler Industry (미국브로일러산업의 경제통합전개과정)

  • 박영인
    • Korean Journal of Poultry Science
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    • v.12 no.2
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    • pp.119-126
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    • 1985
  • The purpose of the study is to review the evolutional process of the U.S. broiler industry into the integrated production and marketing systems and to examine the factors influenced such a structural change over the Past half a century. The study is also carried out under the consideration that the experience gained by the integrated U.S. broiler industry could be utilized in applying the system to any non-integrated broiler industries like one in Korea. The U.S. broiler industry has been prevailed in the typical independent operation of all stages, from factor supply through growing to dressing and marketing until such time as growers began to suffer from financial difficulties right after the end of the World Wat II due mainly to lowered price of broilers stemmed from whopping decrease of the demand, which eventually reflected to the allied agribusiness sectors. The feed business field was the first reactor to this situation so that a kind of measures was taken to cope with the problems faced in such a way to provide extended credit on feeds first and help obtain chicks or sell broilers later. This trend has been practiced for broiler related agribusiness through late 1940's to work together with growers by coordinating its function between two or more stages involved in broiler production and marketing process as a means of spreading risk and sharing profit between stages Participated. The integrated system and contract farming thus became Popular across the country through mid 1950's.

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BIM Application Method for the Quality Management of Modular Houses (모듈러주택 품질관리를 위한 BIM 적용 방안)

  • Lee, Dong Gun;Kim, Jin Won;Sohn, Jeong Rak
    • Land and Housing Review
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    • v.10 no.2
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    • pp.59-67
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    • 2019
  • The recent paradigm shift in the construction industry has led to a growing demand for industrial construction. In particular, interest in modular housing, one of the areas of industrialization architecture, is soaring. Modular housing is a construction method for completing a building by transporting factory-built modules to the site and assembling them. However, modular housing in Korea has various problems such as errors in design books, lack of factory drawings, and lack of on-site construction plans. BIM is a tool for accumulating, producing and managing various information through 3D models and is a solution to solve various problems of modular housing. In this study, problems of modular housing and BIM utilization of modular housing were presented as ways to ensure the quality of modular housing. Therefore, this study analyzed the problems that are occurring in the construction process of modular housing. And, to address the problem of modular housing, BIM utilization measures were proposed for each modular process step. However, the application of BIM in domestic modular project is currently being carried out in pilot research project. Because of this, the BIM utilize method for modular housing is limited based on the BIM use for general projects and the examples for some modular pilot projects.

Genome Scale Protein Secondary Structure Prediction Using a Data Distribution on a Grid Computing

  • Cho, Min-Kyu;Lee, Soojin;Jung, Jin-Won;Kim, Jai-Hoon;Lee, Weontae
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.65-65
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    • 2003
  • After many genome projects, algorithms and software to process explosively growing biological information have been developed. To process huge amount of biological information, high performance computing equipments are essential. If we use the remote resources such as computing power, storages etc., through a Grid to share the resources in the Internet environment, we will be able to obtain great efficiency to process data at a low cost. Here we present the performance improvement of the protein secondary structure prediction (PSIPred) by using the Grid platform, distributing protein sequence data on the Grid where each computer node analyzes its own part of protein sequence data to speed up the structure prediction. On the Grid, genome scale secondary structure prediction for Mycoplasma genitalium, Escherichia coli, Helicobacter pylori, Saccharomyces cerevisiae and Caenorhabditis slogans were performed and analyzed by a statistical way to show the protein structural deviation and comparison between the genomes. Experimental results show that the Grid is a viable platform to speed up the protein structure prediction and from the predicted structures.

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A Study on Development Process of Experience Program in 'Recreating Cultural and Traditional Village' - Focusing on Development Process of Experience Program in '2005 Andong Gunjamaul Recreating Cultural and Traditional Village' - (문화.역사마을가꾸기 체험프로그램 개발방법에 관한 연구 -2005 안동 군자마을 문화.역사마을가꾸기 체험프로그램 개발과정을 중심으로-)

  • Shin, Joong-Jin;Kim, Chi-Kyung
    • Journal of architectural history
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    • v.15 no.4
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    • pp.7-22
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    • 2006
  • The purpose of this study is proposing a method of developing experience program for organizing continuous 'Recreating Cultural and Traditional Village'. Therefore, with having purpose of developing experience program which is deeply related with residents organization and architecture in the village, the researcher has participated in '2005 An-dong Gunjamaul Recreating Cultural and Traditional Village', accomplished developing experience program which can continuously manageable by residents and space and facilities which are accompanied with program. The results of this research are as follows. The developing process of experience program has four phases, selecting program, planning program, growing and changing program, and practicing and firmly establishing program. Moreover, the relationships between space planning and setting up a resident's organization and the experience program need to be considered. The things that experts have to consider are come up with three subjects. First, planning experience program with citizen participation. Second, designing experience program with spaces which will contain the programs. Third, developing programs which are accompanied with rediscover village's resources through continuous feedback.

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Development of STAGE-GATE based Evaluation Index for the Improvement of Design Quality of Plant Material (플랜트 기자재 설계품질 향상을 위한 STAGE-GATE 기반 평가항목 개발)

  • Lee, In Tae;Baek, Dong Hyun
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.43 no.2
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    • pp.65-71
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    • 2020
  • Worldwide plant market keeps maintaining steady growth rate and along with this trend, domestic plant market and its contractors also maintain such growing tendency. However, in spite of its external growth, win-win growth of domestic material industry that occupies the biggest share in plant industry cost portion is extremely marginal in reality. Domestic plant material suppliers are required to increase awareness of domestic material brand by securing quality and reliability of international standard through improvement of design quality superior to that of overseas material suppliers. Improvement of design quality of plant material becomes an essential element, not an option, for survival of domestic plant industry and its suppliers. Under this background, in this study, priority and importance by each evaluation index was analyzed by materializing plant design stage through survey of experts and defining evaluation index by each design stage and based on this analysis result, evaluation index of stage-gate based decision-making process that may improve design quality of plant material was suggested. It is considered that by utilizing evaluation index of stage-gate based decision-making process being suggested in this study, effective and efficient decision-making of project decision-makers would be enabled and it would be contributory to improve design quality of plant material.

Identifying Wastes in Construction Process and Implementing the Last Planner System in India

  • Bhatla, Ankit;Pradhan, Bulu;Choi, Jin Ouk
    • Journal of Construction Engineering and Project Management
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    • v.6 no.1
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    • pp.11-19
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    • 2016
  • Most of the Indian contractors are not well equipped to handle the growing demand of infrastructure development; hence construction projects frequently run in to time and cost overruns, disputes and quality issues. This study aims to improve the construction industry in India by implementing lean principles to eliminate non-value adding activities (wastes). The purpose of this study is to 1) identify the wastes and their sources affecting the construction process, and 2) to identify problems and document lessons by applying a Last Planner System (LPS) to a sample project. First, the researchers identified that Delays, Rework, and Interruptions were the most critical wastes affecting the construction process and Poor management control, Poor Planning and Shortage of Resources were the major sources of the above mentioned wastes. Second, the researchers report the Percent of Planned Complete (PPC) analysis results and experienced problems after implementation of LPS at the sample project. It was observed that much more improvement could have been achieved if there was consensus between the owners and the contractor on the implementation of the LPS in its entirety. Some of the problems experienced in the implementation of the LPS like lack of scheduling, resource and material shortage were found to be similar to those in developed countries.

Conservation Methods for Historic Rural Settlements - with focus on foreign precedents - (농촌 정주형 역사환경 보전방법론 고찰 - 외국 선례를 중심으로 -)

  • 강동진
    • Journal of Korean Society of Rural Planning
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    • v.4 no.2
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    • pp.41-57
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    • 1998
  • Now, the conservation policy of historic environments in Korea which started in early 1980's, is in a danger. In addition, because of economic crisis started last year, the concerns for historic environments are growing weaker. However, this situation can be a good opportunity to prepare for the coming conservation works, The purpose of this study is to find clues for conservation of historic environments by considering foreign precedents. For concrete results, this study selects historic rural settlements as a case and focuses on the relationship among related people in the light of the their rights. Based on the consideration of foreign precedents, three different characters in the conservation process could be identified compared with korean cases; 1) Except partial works of public sector, generally the conservation process is under the control of nonprofit groups and residents themselves, 2) Conservation methods include with the proper change process for the sustainable settlement, and avoid the unconditional past-oriented approach, 3) Conservation methods are composed of not only the preservation of external forms such as assets but also the continuous participation and management of the community. And the most important clue which has been extracted is that the diverse rights of related people in the historic rural settlements should be kept in balance thoroughly.

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Two Dimensional (2D) Nanomaterials based Composite Membrane for Desalination (2차원 나노재료 기반 복합막을 이용한 해수담수화)

  • Lee, Yu Kyung;Patel, Rajkumar
    • Membrane Journal
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    • v.30 no.2
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    • pp.111-123
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    • 2020
  • Growing industrialization and climate change lead to the huge demand for clean drinking water. Desalination of sea water by membrane separation process is one of the alternative and economically viable methods to fulfil the demand for water. In the membrane separation process, the presence of 2D materials enhances the performance of membrane by facilitating the water permeation, salt rejection, flux rate, and selectivity compared to the traditional reverse osmosis thin-film-composite membranes. In this review, composite membranes with different kinds of 2D materials are discussed on the basis of materials synthesis, characterization and desalination process.