• Title/Summary/Keyword: theoretical analyses

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Urban Revitalization Policies of the Ruhr Area, Germany: Case Studies on the Cities of Oberhausen and Gelsenkirchen (독일 루르지역의 도시재생정책: 오버하우젠시와 겔젠키르헨시를 사례로)

  • Shin, Dong-Ho
    • Journal of the Economic Geographical Society of Korea
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    • v.18 no.1
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    • pp.60-75
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    • 2015
  • The Ruhr area in the Northwestern Germany grew rapidly from the 1850s based on coal mining and iron and steel industries, playing a key role as an engine of industrial growth. Since the 1950s, however, the area has been experiencing a serious economic crisis as the traditional industries declined. The crisis was comprised of increasing unemployment and abandoned industrial lands and facilities. Oberhausen and Gelsenkirhen are typical cities of the Ruhr, characterized by such economic crisis. Oberhausen attempted to solve the problems by developing a large leisure town, composed of a sopping mall, restaurants, and other arts and cultural activities, on a former steel mill site. Gelsenkirhen, on the other hand, went on to promote renewable energy industries, business incubators, and energy-saving housing complexes. This paper analyses the processes and outcomes of urban revitalization policies of the two cities, based on the path dependence theory, and draws theoretical and policy implications.

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An Empirical Study on Critical Success Factors in Implementing the Web-Based Distance Learning System : In Case of Public Organization. (사이버교육 효과의 영향요인에 관한 실증적 연구: 공공조직을 중심으로)

  • 정해용;김상훈
    • The Journal of Information Systems
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    • v.11 no.1
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    • pp.51-74
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    • 2002
  • The purpose of this study is to empirically investigate critical success factors for effective implementation of web-based distance learning system. First of all, four critical success factors are theoretically derived from reviewing previous research. They are: (1) learner-related factor including the variables such as teaming ability, learning attitude, and attending motivation, (2) environmental factor including the variables of physical and mental support for learners, (3) instructional design factor represented by one variable, the degree of appropriateness of learning contents, and (4) the factor concerning the level of self-directed learning readiness embracing the variables such as curiosity for learning, openness towards challenge of learning and affection for learning. Subsequently, the relationships between these four critical success factors and the degree of learning satisfaction are empirically investigated. The data for empirical analysis of the research are collected from 1,020 respondents who have already passed the web-based distance learning courses which have been implemented in Information and Communication Officials Training Institute. Out of 1,020 responded questionnaires, 875 data were available for statistical analyses. The main results of this study are as follows. Firstly, the most important factor for successful implementation of the web-based distance learning system is shown to be the instructional design factor, and in the next place, the self-directed learning readiness factor, the environmental factor and the learner-related one in sequence. Secondly, additional analysis of the variables included in the instructional design factor shows that availability of practical information and knowledge is the most influencing variable, and next, interesting composition of contents, reasonable learning amount, optimal level of instruction, and understandable explanation are significantly important in the descending order. Lastly, among learning motivators, strong intention of acquiring business knowledges and skills is found to be the most important satisfier in the web-based distance learning. The theoretical contribution of this study is to derive a comprehensive model of critical success factors for implementing the web-based distance learning system. And, the practical implication of this study is to propose efficient and effective guidelines for developing and operating the web-based distance learning system in the various kinds of organizations.

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Digital Chaotic Communication System Based on CDSK Modulation (CDSK 방식의 디지털 카오스 통신 시스템)

  • Bok, Junyeong;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.6
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    • pp.479-485
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    • 2013
  • Recently, interest for wireless communication technology with improved security and low eavesdropping probability is increasing rapidly recognizing that information security is an important. Chaos signal can be used encode information efficiently due to irregular phenomena. Chaotic signal is very sensitive to the initial condition. Chaos signal is difficult to detect the signal if you do not know the initial conditions. Also, chaotic signal has robustness to multipath interference. In this paper, we evaluate the performance of correlation delay shift keying (CDSK) modulation with different chaotic map such as Tent map, Logistic map, Henon map, and Bernoulli shift map. Also, we analyze the BER performance depending on the selection of spreading factor (SF) in CDSK. Through the theoretical analyses and simulations, it is confirmed that Henon map has better BER performance than the other three chaotic maps when spreading factor is 70.

On the Predictability of Heavy Snowfall Event in Seoul, Korea at Mar. 04, 2008 (폭설에 대한 예측가능성 연구 - 2008년 3월 4일 서울지역 폭설사례를 중심으로 -)

  • Ryu, Chan-Su;Suh, Ae-Sook;Park, Jong-Seo;Chung, Hyo-Sang
    • Journal of Environmental Science International
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    • v.18 no.11
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    • pp.1271-1281
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    • 2009
  • The heavy snowfall event over the eastern part of Seoul, Korea on Mar. 04, 2008 has been abruptly occurred after the frontal system with the heavy snowfall event had been past over the Korean peninsula on Mar. 03, 2008. Therefore, this heavy snowfall event couldn't be predicted well by any means of theoretical knowledges and models. After the cold front passed by, the cold air mass was flown over the peninsula immediately and became clear expectedly except the eastern part and southwestern part of peninsula with some large amount of snowfall. Even though the wide and intense massive cold anticyclone was expanded and enhanced by the lowest tropospheric baroclinicity over the Yellow Sea, but the intrusion and eastward movement of cold air to Seoul was too slow than normally predicted. Using the data of numerical model, satellite and radar images, three dimensional analysis Products(KLAPS : Korea Local Analysis and Prediction System) of the environmental conditions of this event such as temperature, equivalent potential temperature, wind, vertical circulation, divergence, moisture flux divergence and relative vorticity could be analyzed precisely. Through the analysis of this event, the formation and westward advection of lower cyclonic circulation with continuously horizontal movement of air into the eastern part of Seoul by the analyses of KLAPS fields have been affected by occurring the heavy snowfall event. As the predictability of abrupt snowfall event was very hard and dependent on not only the synoptic atmospheric circulation but also for mesoscale atmospheric circulation, the forecaster can be predicted well this event which may be occurred and developed within the very short time period using sequential satellite images and KLAPS products.

A Study on Ground Vehicle Mechanics for Steep Slope Forest Operations - Rubber-Tired Log Skidding Tractor Operations - (급경사지 산림작업을 위한 차량의 역학분석에 관한 연구 -차륜형 집재작업 트랙터를 중심으로-)

  • Chung, Joo Sang;Chung, Woo Dam
    • Journal of Korean Society of Forest Science
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    • v.84 no.2
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    • pp.218-225
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    • 1995
  • In this paper, a mechanical analysis model for steep-slope log-skidding operations of a rubber-tired tractor is discussed and the applicability of the model is investigated. The model largely consists of mathematical analysis models for log drag, dynamic vehicle weight distributions and soil-vehicle traction. For the case study, a theoretical data set for log skidding operations is used in investigating the effect of the factors influencing the results of mechanical analysis or the productivity of skidding operations. The analyses include 1) the effect of log choking methods on tangential log-skidding force, 2) the effects of the change in travel speed and log load on the required input power to the wheels and 3) the log skidding performance of a two-wheel drive compared with that of a four-wheel drive.

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A Semiotic Analysis of Orientalism Reflected in Modern Clothing (현대복식에 반영된 오리엔탈리즘의 기호학적 분석)

  • 이춘희;신상옥
    • Journal of the Korean Society of Costume
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    • v.50 no.4
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    • pp.131-146
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    • 2000
  • The starting point of this study was that the Orientalism reflected in the modern clothing is realized the different view by Western and Eastern. Based on this regard, this study semiotically analyse that clothing is creating the cultural values and signification and that the western designers are reproducing an ideology as orientalism being the western-oriented thought when expressing the Asian image in the modern clothing. The theoretical sides are based on the semiotic analyses of F. Saussure, C. Peirce, and R. Barthes. By the result observed through this study, the Orientalism reflected in the modern clothing designed by Western designers are discriminative image, mystic image, past-oriented image, natural image, and complex-eclectic image. The discriminative image is reproduced as a savage and uncivilized image. In addition, it regarded as a decorative and superficial image is expressed as if it is an uncharacterized and underdeveloped image in the modern clothing. The mystic image is reproduced as a romantic image to stimulate Westerners'curiosity. That is, Asian image is regarded as a dream and magical image rather than a scientific and rational image. The past-oriented image is expressed through restricting Asian positive image in Asian historical glory. The natural image differs from Western image based on science in the modern clothing. The modern clothing regards the natural image as a primitive and instinctive image. The complex-eclectic image is the pastish pattern through selecting and distributing heterogeneous materials in the modern clothing. This study critically analyzes the western-oriented thought of orientalism in the modern clothing. The results of the study imply that it is critical that we provide a new contact point for the East and the West in the context of our Asian values and traditions.

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Stress Analysis of Cold Rolled Strip Coiling Process (냉연재 권취공정의 응력해석)

  • Park, Kyu Tae;Park, Yong Hui;Park, Hyun Chul;Won, Sung Yeun;Hong, Wan Kee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.5
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    • pp.409-414
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    • 2017
  • In the thin strip coiling process, it is necessary to use a sleeve with a mandrel to prevent excessive deformation of the strip. The stress distribution in the sleeve and strip is an important factor to determine the size of the sleeve. However, an experimental approach is almost impossible because of the accumulation of high pressure. A finite element (FE) model of the strip coiling process was developed in this study. Then, the radial and hoop stresses on the sleeve and strip were investigated using FE analyses. The theoretical values and analysis results under idealized conditions were compared to verify the FE model. The effect of the strip thickness on the stress distribution was also investigated. The radial stress increased by 6.3 times for a 1-mm-thick strip at the coil starting point. The radial stress at the sleeve increased by 14.8 % with a stacked thickness of 90 mm because of the reaction force applied by the mandrel.

Theoretical Studies on Electronic Structure and Absorption Spectrum of Prototypical Technetium-Diphosphonate Complex 99mTc-MDP

  • Qiu, Ling;Lin, Jian-Guo;Gong, Xue-Dong;Ju, Xue-Hai;Luo, Shi-Neng
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2358-2368
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    • 2011
  • Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations, employing the B3LYP method and the LANL2DZ, 6-31G$^*$(LANL2DZ for Tc), 6-31G$^*$(cc-pVDZ-pp for Tc) and DGDZVP basis sets, have been performed to investigate the electronic structures and absorption spectra of the technetium-99m-labeled methylenediphosphonate ($^{99m}Tc$-MDP) complex of the simplest diphosphonate ligand. The bonding situations and natural bond orbital compositions were studied by the Mulliken population analysis (MPA) and natural bond orbital (NBO) analysis. The results indicate that the ${\sigma}$ and ${\pi}$ contributions to the Tc-O bonds are strongly polarized towards the oxygen atoms and the ionic contribution to the Tc-O bonding is larger than the covalent contribution. The electronic transitions investigated by TDDFT calculations and molecular orbital analyses show that the origin of all absorption bands is ascribed to the ligand-to-metal charge transfer (LMCT) character. The solvent effect on the electronic structures and absorption spectra has also been studied by performing DFT and TDDFT calculations at the B3LYP/6-31G$^*$(cc-pVDZ-pp for Tc) level with the integral equation formalism polarized continuum model (IEFPCM) in different media. It is found that the absorption spectra display blue shift in different extents with the increase of solvent polarity.

Theoretical Characterization of Binding Mode of Organosilicon Inhibitor with p38: Docking, MD Simulation and MM/GBSA Free Energy Approach

  • Gadhe, Changdev G.;Balupuri, Anand;Kothandan, Gugan;Cho, Seung Joo
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2494-2504
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    • 2014
  • P38 mitogen activated protein (MAP) kinase is an important anti-inflammatory drug target, which can be activated by responding to various stimuli such as stress and immune response. Based on the conformation of the conserved DFG loop (in or out), binding inhibitors are termed as type-I and II. Type-I inhibitors are ATP competitive, whereas type-II inhibitors bind in DFG-out conformation of allosteric pocket. It remains unclear that how these allosteric inhibitors stabilize the DFG-out conformation and interact. Organosilicon compounds provide unusual opportunity to enhance potency and diversity of drug molecules due to their low toxicity. However, very few examples have been reported to utilize this property. In this regard, we performed docking of an inhibitor (BIRB) and its silicon analog (Si-BIRB) in an allosteric binding pocket of p38. Further, molecular dynamics (MD) simulations were performed to study the dynamic behavior of the simulated complexes. The difference in the biological activity and mechanism of action of the simulated inhibitors could be explained based on the molecular mechanics/generalized Born surface area (MM/GBSA) binding free energy per residue decomposition. MM/GBSA showed that biological activities were related with calculated binding free energy of inhibitors. Analyses of the per-residue decomposed energy indicated that van der Waals and non-polar interactions were predominant in the ligand-protein interactions. Further, crucial residues identified for hydrogen bond, salt bridge and hydrophobic interactions were Tyr35, Lys53, Glu71, Leu74, Leu75, Ile84, Met109, Leu167, Asp168 and Phe169. Our results indicate that stronger hydrophobic interaction of Si-BIRB with the binding site residues could be responsible for its greater binding affinity compared with BIRB.

The effects of entrepreneurship on innovational Behavior orientation: Focused on examining mediator effects of Affective Organizational Commitment (기업가정신과 종업원의 혁신행동지향성에 대한 정서적 몰입의 매개효과)

  • Kwon, Hyeok-Ki;Son, Heon-Il
    • Management & Information Systems Review
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    • v.33 no.3
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    • pp.77-92
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    • 2014
  • The objective of this study is to examine the factors influencing entrepreneurship and innovational behavior orientation in small and middle enterprise. This model tests various theoretical research hypotheses relating to entrepreneurship, innovational behavior orientation and Affective Organizational Commitment. To verify them, using a sample of 280 employees working for 31 companies in Busan, Ulsan, and Pohang, this study analyses empirically on structural relationship among them. The results of hypothesis testing are as follows. First, entrepreneurship influence innovational orientation. Second, entrepreneurship influence Affective Organizational Commitment. Finally, A mediator effect of Affective Organizational Commitment between entrepreneurship and innovational behavior orientation is a new empirical result coming out of this study. The study provides entrepreneurship and policy-HRM with more accurate information that allow them to explore significant managerial insights so as to develop appropriate policy in small and middle enterprise.

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