• Title/Summary/Keyword: efficiency of scale

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The Post-IMF firm strategy and the corporate restructuring in the heavy & chemical industrial district: the case of Ulsan, Korea (울산 중화학공업의 재구조화 특성 - IMF 체제 이후의 기업전략을 중심으로 -)

  • Park, Yang-Choon
    • Journal of the Korean association of regional geographers
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    • v.7 no.2
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    • pp.17-34
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    • 2001
  • This paper is to analyze how firms in a large firm-led industrial city have carried out the restructuring in the face of radical shifts, with focus on the strategy and the restructuring of firms in Ulsan, a typical industrial district in Korea that is specialized in heavy & chemical industry. It has been well known that the local economy has been led by a small number of large firms, including affiliates of chaebol, and its industrial structure has also been characterised as a clear dichotomy between large firms as a customer and small and medium-size firms as a supplier, which can be called not horizontal but vertical relations. It can identify some tendencies, however, that local companies have been rather dynamically changing in response to increasingly turbulent environment since the Asian crisis. Some are radical, but some incremental. These can be summarized in four distinctive but interlinked ways. First, more than half of local companies surveyed have attempted to change their production systems, mainly from the fordist mass production towards the flexible mass production, seeking both economies of scale and scope. Second, local firms have vigorously continued to reorganize the boundary of the production and the organization, by specializing products and focusing on the core competence in order to save costs and cope with radically changing customer demands in a flexible way. Third, there have been various strategies for the organizational innovation such as the introduction of team organization, the boundary blurring between the managerial and production workers and the intra-firm spin-offs, so as to improve managerial efficiency and competence in the use of internal labour market. Finally, they have tried to be more sensitive to the market and customers. These tendencies seem to be increasingly critical to sustain their competitiveness. To do so, they tend to focus increasingly not only on the competing via the product quality rather than through price, but also to seek to diversify the market and customer firms beyond national boundary.

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High Energy Density Germanium Anodes for Next Generation Lithium Ion Batteries (다음세대 리튬이온 배터리용 고에너지 밀도 게르마늄 음극)

  • Ocon, Joey D.;Lee, Jae Kwang;Lee, Jaeyoung
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.1-13
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    • 2014
  • Lithium ion batteries (LIBs) are the state-of-the-art technology among electrochemical energy storage and conversion cells, and are still considered the most attractive class of battery in the future due to their high specific energy density, high efficiency, and long cycle life. Rapid development of power-hungry commercial electronics and large-scale energy storage applications (e.g. off-peak electrical energy storage), however, requires novel anode materials that have higher energy densities to replace conventional graphite electrodes. Germanium (Ge) and silicon (Si) are thought to be ideal prospect candidates for next generation LIB anodes due to their extremely high theoretical energy capacities. For instance, Ge offers relatively lower volume change during cycling, better Li insertion/extraction kinetics, and higher electronic conductivity than Si. In this focused review, we briefly describe the basic concepts of LIBs and then look at the characteristics of ideal anode materials that can provide greatly improved electrochemical performance, including high capacity, better cycling behavior, and rate capability. We then discuss how, in the future, Ge anode materials (Ge and Ge oxides, Ge-carbon composites, and other Ge-based composites) could increase the capacity of today's Li batteries. In recent years, considerable efforts have been made to fulfill the requirements of excellent anode materials, especially using these materials at the nanoscale. This article shall serve as a handy reference, as well as starting point, for future research related to high capacity LIB anodes, especially based on semiconductor Ge and Si.

Reference Station of Aerial Photogrammetry with GPS/INS by VRS (GPS/INS 항공사진측량의 지상기준국 측량의 VRS(가상기준점)적용에 관한 연구)

  • Song, Tae-Min;Kwon, Jay-Hyoun
    • Korean Journal of Remote Sensing
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    • v.24 no.4
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    • pp.381-388
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    • 2008
  • In the common practice of air-photographing measurement aerial-photogrammetric, the location of camera at the time of photographing is identified by performing aerotriangulation. However, installing ground-base station to enable aerotriangulation takes majority portion of a map making cost. Aerial-photogrammetric has shown a great improvement helped by steady upgrading in equipment and development in quantitative study. Aerotriangulation can be replaced by Direct Georeferencing, which uses GPS/INS to identify a camera location and to produce detailed information. An innovative technique replacing aerotriangulation, it has a disadvantage that base station has to be available in the area of photographing. The study intends to suggest a method applying VRS in GPS/INS aerotriangulation. Despite the fact that Direct Georeferencing is the innovated technique which substitutes existing aerotriangulation, it still need to install the ground-base station in GPS/INS aerotriangulation. GPS/INS data was analyzed with 4 different cases in order to accomplish the purpose of this study. In addition, in the thesis, it was approved that VRS can be utilized to make small-scale map as accurate as base station. This study is expected to improve the efficiency of work by showing that VRS can be used not only in base station but also enabling base station in the ground-access challenging area.

Construction of Mine Geospatial Information by Total Station and 3D Laser Scanner (토털스테이션과 3D 레이저 스캐너에 의한 광산공간정보 구축)

  • Park, Joon-Kyu;Lee, Keun-Wang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.520-525
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    • 2019
  • Mines are an important infrastructure for securing resources, but safety problems can arise in the course of operation. Recently, the mining process is very complicated due to the large scale and mechanization. Therefore, it is necessary to construct accurate geospatial information on mine for systematic and safe mine operation. The geospatial information construction using the existing total station has a disadvantage that a lot of work time is required because the target must be collimated and measured. In this study, the data of the mines were acquired with the total station and the 3D laser scanner, and the mine spatial information was constructed by using the shape based registration method. By using the static scanner data of some area applying the reference point surveying result of the total station, it was possible to construct the accurate result on the wide area acquired by the mobile scanner effectively. Also, the accuracy of the constructed geospatial information was evaluated and the deviation of mean 0.083m was shown. Point cloud products constructed through the research can contribute to the efficiency improvement of mine management by enabling quantitative analysis such as visualization of mine shape, distance, area and slope, and automation of drawing creation for cross section shape.

Impact of Expanded Small Alkyl-Binding Pocket by Triple Point Mutations on Substrate Specificity of Thermoanaerobacter ethanolicus Secondary Alcohol Dehydrogenase

  • Dwamena, Amos K.;Phillips, Robert S.;Kim, Chang Sup
    • Journal of Microbiology and Biotechnology
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    • v.29 no.3
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    • pp.373-381
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    • 2019
  • Site-directed mutagenesis was employed to generate five different triple point mutations in the double mutant (C295A/I86A) of Thermoanaerobacter ethanolicus alcohol dehydrogenase (TeSADH) by computer-aided modeling with the aim of widening the small alkyl-binding pocket. TeSADH engineering enables the enzyme to accept sterically hindered substrates that could not be accepted by the wild-type enzyme. The underline in the mutations highlights the additional point mutation on the double mutant TeSADH introduced in this work. The catalytic efficiency ($k_{cat}/K_M$) of the ${\underline{M151A}}$/C295A/I86A triple TeSADH mutant for acetophenone increased about 4.8-fold higher than that of the double mutant. A 2.4-fold increase in conversion of 3'-methylacetophenone to (R)-1-(3-methylphenyl)-ethanol with a yield of 87% was obtained by using ${\underline{V115A}}$/C295A/I86A mutant in asymmetric reduction. The ${\underline{A85G}}$/C295A/I86A mutant also produced (R)-1-(3-methylphenyl)-ethanol (1.7-fold) from 3'-methylacetophenone and (R)-1-(3-methoxyphenyl)-ethanol (1.2-fold) from 3'-methoxyacetophenone, with improved yield. In terms of thermal stability, the ${\underline{M151A}}$/C295A/I86A and ${\underline{V115A}}$/C295A/I86A mutants significantly increased ${\Delta}T_{1/2}$ by $+6.8^{\circ}C$ and $+2.4^{\circ}C$, respectively, with thermal deactivation constant ($k_d$) close to the wild-type enzyme. The ${\underline{M151A}}$/C295A/I86A mutant reacts optimally at $70^{\circ}C$ with almost 4 times more residual activity than the wild type. Considering broad substrate tolerance and thermal stability together, it would be promising to produce (R)-1-(3-methylphenyl)-ethanol from 3'-methylacetophenone by ${\underline{V115A}}$/C295A/I86A, and (R)-1-phenylethanol from acetophenone by ${\underline{M151A}}$/C295A/I86A mutant, in large-scale bioreduction processes.

Recent Developments in Quantum Dot Patterning Technology for Quantum Dot Display (양자점 디스플레이 제작을 위한 양자점 패터닝 기술발전 동향)

  • Yeong Jun Jin;Kyung Jun Jung;Jaehan Jung
    • Journal of Powder Materials
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    • v.31 no.2
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    • pp.169-179
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    • 2024
  • Colloidal quantum dot (QDs) have emerged as a crucial building block for LEDs due to their size-tunable emission wavelength, narrow spectral line width, and high quantum efficiency. Tremendous efforts have been dedicated to improving the performance of quantum dot light-emitting diodes (QLEDs) in the past decade, primarily focusing on optimization of device architectures and synthetic procedures for high quality QDs. However, despite these efforts, the commercialization of QLEDs has yet to be realized due to the absence of suitable large-scale patterning technologies for high-resolution devices., This review will focus on the development trends associated with transfer printing, photolithography, and inkjet printing, and aims to provide a brief overview of the fabricated QLED devices. The advancement of various quantum dot patterning methods will lead to the development of not only QLED devices but also solar cells, quantum communication, and quantum computers.

A Study on Adjustment of Operational Factor in A2O process (A2O공정 운전인자 조정에 대한 연구)

  • Yoo, Ho-Sik;Lee, Byonghi
    • Journal of the Korea Organic Resources Recycling Association
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    • v.23 no.3
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    • pp.33-41
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    • 2015
  • An alternative was investigated to maximize the treatment efficiency of wastewater treatment plant without large scale expansion. 79% of detention time was required for enough nitrogen control. As aeration time was extended, nitrification was processed, but opposite trend was seen in phosphorus. High concentration of $NO_3-N$ interrupted PAOs activity not to absorb phosphorus. An alternative was devised for selective use of anaerobic or anoxic zone. Trisection was suggested for alternative use of center room. The result was relatively successful. The concentration of phosphorus was reduced with reduction of nitrogen. Extended anaerobic condition seemed to stimulate denitrification. Valve connection of internal return from aeration tank will make it possible to use middle room alternatively. This method will be a good alternative for seasonal variation of water temperature.

Simulation Study on E-commerce Recommender System by Use of LSI Method (LSI 기법을 이용한 전자상거래 추천자 시스템의 시뮬레이션 분석)

  • Kwon, Chi-Myung
    • Journal of the Korea Society for Simulation
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    • v.15 no.3
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    • pp.23-30
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    • 2006
  • A recommender system for E-commerce site receives information from customers about which products they are interested in, and recommends products that are likely to fit their needs. In this paper, we investigate several methods for large-scale product purchase data for the purpose of producing useful recommendations to customers. We apply the traditional data mining techniques of cluster analysis and collaborative filtering(CF), and CF with reduction of product-dimensionality by use of latent semantic indexing(LSI). If reduced product-dimensionality obtained from LSI shows a similar latent trend of customers for buying products to that based on original customer-product purchase data, we expect less computational effort for obtaining the nearest-neighbor for target customer may improve the efficiency of recommendation performance. From simulation experiments on synthetic customer-product purchase data, CF-based method with reduction of product-dimensionality presents a better performance than the traditional CF methods with respect to the recall, precision and F1 measure. In general, the recommendation quality increases as the size of the neighborhood increases. However, our simulation results shows that, after a certain point, the improvement gain diminish. Also we find, as a number of products of recommendation increases, the precision becomes worse, but the improvement gain of recall is relatively small after a certain point. We consider these informations may be useful in applying recommender system.

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Relations between the State and the Local in the Construction of Masan Export Processing Zone (마산수출자유지역의 형성을 둘러싼 국가-지방 관계에 대한 연구)

  • Park, Bae-Gyoon;Choi, Young Jin
    • Journal of the Korean Geographical Society
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    • v.49 no.2
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    • pp.113-138
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    • 2014
  • Despite the growing numbers of regional problems (e.g. conflicts between the state and localities, inter-local conflicts, etc.) associated with the state-led developmental projects, the Korean social sciences have been unable to offer satisfying explanations and solutions to the regional problems. This is mainly because the existing works, which have been taken captured by the assumptions of "methodological nationalism", significantly lack the socio-spatial understandings of the state actions and the relations between the state and localities, thereby seeing the issues of regional development mainly in terms of either the economic efficiency defined at the national scale, or the plan rationality of the national bureaucrats. With this problem orientation in mind, this paper aims to explore the ways in which the state and localities are interacting, conflicting and negotiating with one another through the mediation of the state-led developmental projects. Focusing on the developmental processes of Masan Export Processing Zone from the mid-1960s to the early 1970s, it examines the multi-scalar processes through which the state-led industrial complex developmental processes have been influenced by the complex and dynamic interactions among social forces and actors acting at diverse geographical scales (e.g. the global, national, local, urban, etc.). This analysis shows that the regional policies of the Korean developmental state were more heavily influenced by the interactions, contestations, and collaborations among social forces and actors, acting in and through the state, at various geographical scales, rather than by the economic and techno-bureaucratic rationality.

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The Barangay Integrated Development Approach for Nutrition Improvement of the Rural Poor, BIDANI(a Nutrition-in-Development Network Program) (지역 종합개발계획 접근에 의한 빈농 영양개선사업 -영양ㆍ개발 네트워크 프로그램-)

  • 박양자
    • Korean Journal of Rural Living Science
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    • v.4 no.2
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    • pp.155-162
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    • 1993
  • BIDANI is the action-research program. BIDANI aims to be truly a people's program embodying their own activities and aspiration. BIDANI sees an integrated development approach at the community level with participatory services embodied in a Barangay Integrated Development Plan(BIDP) designed by the people themselves. Community situational analysis is conducted by the people to identify the priority problems and potential resources in the barangay. Participatory planning, using the “bottom up” apporach, is exercised to formulate a BIDP. Proper motivation and advocacy encourage barangay people's participation. Accessibility and efficiency in the use of various services and resources of government and private agencies increase. Family groups who are at high-risk to malnutrition become aware of the importance of nutrition through their participation in development program activities. Integration of political and socio-economic concerns at the lowest level is operationalized. Implementation and sustainability of the program on a wider scale from a model project to a model program is facilitated through institutionalization at the municipal/city level with the mayor as the project director. “Top to bottom” planning through a City/Municipal Integrated Development Program(C/MIDP) interacts with “bottom up” planning at the barangay level. The establishment of a local Training School for Barangay Development(TSBD) in each municipality and city for continuing education of indigenous village workers and barangay people is a vital component for success and viability. The role of non-political entities such as academic institutions and non-government organizations, as catalytic agents of development, is stressed.

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