• Journal of Communications and Networks
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• 제16권2호
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• pp.217-226
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• 2014

In this research, we study the problem of opportunistic spectrum access (OSA) in a time-varying environment with fading channels, where the channel state is characterized by both channel quality and the occupancy of primary users (PUs). First, a finite-state Markov channel model is introduced to represent a fading channel. Second, by probing channel quality and exploring the activities of PUs jointly, a two-dimensional partially observable Markov decision process framework is proposed for OSA. In addition, a greedy strategy is designed, where a secondary user selects a channel that has the best-expected data transmission rate to maximize the instantaneous reward in the current slot. Compared with the optimal strategy that considers future reward, the greedy strategy brings low complexity and relatively ideal performance. Meanwhile, the spectrum sensing error that causes the collision between a PU and a secondary user (SU) is also discussed. Furthermore, we analyze the multiuser situation in which the proposed single-user strategy is adopted by every SU compared with the previous one. By observing the simulation results, the proposed strategy attains a larger throughput than the previous works under various parameter configurations.

• World Technopolis Review
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• 제8권1호
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• pp.21-42
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• 2019

The purpose of this research was to investigate the factors influencing global expansion/scalability of Kenyan Small and Medium Enterprises (SMEs). Factor analysis and multiple/multivariate regression analysis to determine the functional relationship between independent variables (factors) and the dependent variable was used. The independent variables were: innovation & technology, fitness/appropriateness of management, global marketing strategy; and support environment and the dependent variable, global expansion/scalability. Data was collected from a survey of randomly selected firms of 205, drawn from a population of 440 firms from Kenya Manufacturers Directory, with 175 firms responding. The key findings from the research in relation to Kenyan SMEs were that: there is a functional relationship between global market strategy and global expansion; there is a functional relationship between innovation and technology orientation and global expansion, there is no significant functional relationship between supportive environment of firms and their global expansion; and there is no significant functional relationship between fitness/appropriateness of management and global expansion/scalability. The implications for practice is that the ranking of the factors in order of priority supports focusing concern on the orientation of business strategy toward global market strategy, market research geared at obtaining foreign market intelligence, innovation and technology, product adaptation, service orientation, collaborative ventures, and long-range vision as key factors in making Kenyan firms successful in the international market. The implication for policy and practice is that there is need for collaboration between industry and government in pursuing policies for global expansion/scalability and among SMEs and large enterprises particularly in areas of rapid technological change.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.523-531
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• 2014

Brushless Dual-Mechanical-Port Electrical Machine (BLDMPEM) is a new type of motor designed for Hybrid Electric Vehicle (HEV), which contains two mechanical ports and two electric ports. Compared with Dual-Mechanical-Port Electrical Machine (DMPEM), the brushless structure brings higher reliability and easier maintenance. In this paper, the model of BLDMPEM is discussed. In Chapter 2, the energy flow and mathematical model of BLDMPEM are analyzed. Then a novel three-phase half-bridge controlled rectifier topology and its control strategy for cruising mode of HEV based on BLDMPEM are proposed in Chapter 3. Compared with the Field Oriented Control (FOC) strategy of BLDMPEM, the proposed method does not require accurate motor parameters, and it is much simpler and easier to be implemented. At last, simulation and experiment results show the feasibility and validity of the proposed strategy.

• 기술혁신연구
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• 제15권1호
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• pp.27-63
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• 2007

Recently, Kim and Mauborgne (2005a) has introduced the concept of blue ocean strategy that provides quantum leap in value innovation, thus creating new market space. This study, based on the blue ocean strategy concept, suggests blue ocean new product development strategy, and attempts to examine how much impact this blue ocean new product development strategy has on new product performance, compared to existing new product development strategy perspectives based on competitive strategy-based new product development strategy and resource-based new product development strategy, in an empirical way. The research results show that the blue ocean new product development strategy has a statistically significant impact on new product performance. In addition, it was revealed that such contingency variables as firm size and environmental dynamism have moderating effect on the relationship between the blue ocean new product development strategy and new product performance. The blue ocean new product development strategy is more effective in the small-sized firms than the large-sized ones, and its effect on new product performance is different according to environmental dynamism.

• 디지털융복합연구
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• 제12권5호
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• pp.101-113
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• 2014

본 연구는 대구경북의 중소기업을 대상으로 전략유형과 성과관리시스템이 경영성과에 미치는 영향에 대한 연구를 통해 중소기업에 적합한 전략유형을 알아보고 그에 맞는 성과관리시스템의 설계를 통해 기업의 경영성과를 개선하고자 하였다. 연구결과 전략유형 중에서 기술혁신형과 생산중점형은 경영성과에 유의적인 영향을 미치는 것으로 나타났으며, 성과관리시스템은 재무적성과와 비재무적성과에 부분적으로 영향을 미치는 것으로 나타났다. 또한 전략유형과 성과관리시스템의 상호작용은 기술혁신형 기업의 경영성과에 유의적인 영향을 미치는 것으로 나타났다. 이러한 결과는 중소기업들이 전략유형에 맞는 성과관리시스템의 구축을 통해 경영성과를 향상 시킬 수 있음을 지지하고, 이를 통해 기업들은 자원의 제약과 무한 경쟁을 이겨내고 지속적인 성장을 할 수 있을 것으로 보인다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3539-3558
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• 2015

This paper investigates and analyzes the default block placement strategy of HDFS. HDFS is a typical representative distributed file system to stream vast amount of data effectively at high bandwidth to user applications. However, the default HDFS block placement policy assumes that all nodes in the cluster are homogeneous, and places blocks with a simple RoundRobin strategy without considering any nodes' resource characteristics, which decreases self-adaptability of the system. The primary contribution of this paper is the proposition of a network load sensitive block placement strategy. We have implemented our algorithm and justify it through extensive simulations and comparison with similar existing studies. The results indicate that our work not only performs much better in the data distribution but also improves write performance more significantly than the others.

• Asian Journal of Innovation and Policy
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• 제1권1호
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• pp.50-70
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• 2012

This paper analyzes the factors that determine technology innovation in Korean manufacturing firms, focusing on the role of intra-firm knowledge diffusion and market strategy in patent production. For empirical analysis, zero-inflated negative binomial (ZINB) regression is applied to the 2009 Human Capital Corporate Panel data. The empirical findings confirm the critical role of intra-firm knowledge-sharing processes in technology innovation; firms with a market-leading strategy oriented to new product development also tend to be prolific in patent production.

• 지식경영연구
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• 제6권2호
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• pp.47-68
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• 2005

The Purpose of this study is to identify relationships between knowledge management performances and such Influence factors of knowledge Management as information technology, knowledge management process, culture & people, strategy & Leadership in Small and Medium-sized Enterprises. In order to test hypotheses, we collected data from 498 SME's employees, then analysed them by SPSSWIN. This results showed as follows; 1. All Influence factors of knowledge Management( information technology, knowledge management process, culture & people, strategy & Leadership) are to advance individual task effectiveness and organization effectiveness significantly. 2. Such Influence factors of knowledge Management as information technology, knowledge management process, culture & people are to improve business efficiency between the company. But strategy & leadership factor is not significant. 3. Influence factors of knowledge Management are different between knowledge performace factors such ac individual task effectiveness, organization effectiveness, and business efficiency between company.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2017년도 춘계학술대회 논문집
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• pp.219-219
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• 2017

This study aims at examining each firm's decision-makings of complex product and system (hereafter CoPS) innovation strategy, so that it tries to reveal the nature and role of CoPS innovations strategy. And it designed a comparative case study along with qualitative methods, by having two mobile operators' digital rights management (hereafter DRM) innovation in South Korea's digital music service industry. Through literature review, this study formulated three research propositions: (i) Each firm's decision-makings of CoPS innovations strategy are analytical negotiation process among economic actors in an industry; (ii) Each firm's market power originated from its market share from the installed base through network effect and switching cost influence decision-makings of CoPS innovation strategies; (iii) Each firm's decision-makings of different CoPS innovation strategies are related to their intension of achieving better market power, consequently dominant design. Through empirical examination of two mobile operators' decision-makings of DRM innovation strategy, this study empirically verified three research propositions.

• 정보학연구
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• 제12권3호
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• pp.25-48
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• 2009

1. CONTENTS 1) RESEARCH OBJECTIVES The purpose of the study was to propose a future oriented urban space production strategy to offer diverse useful services to citizens to improve international competitiveness of cities in the times of competition that competitive subjects were changed from competition among countries to competition among cities. 2) RESEARCH METHOD In the proposed future-oriented urban space production strategy, the study compared/analyzed main plans related to development of urban space by selecting CBD(Jung-gu) of Busan out of local metropolises in South Korea. 3) RESEARCH FINDINGS In the proposed future-oriented urban space production strategy, the study largely sorted city's function into four scopes function of industrial support, function of social support, function of living support and function of urban infrastructure. 2. RESULTS It is expected that the proposed future oriented urban space production strategy will be utilized as a useful reference model when a lot of local governments, planning a ubiquitous urban space, establish a plan for constructing a ubiquitous urban space.