• ETRI Journal
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• v.38 no.4
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• pp.606-611
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• 2016

This paper presents antenna selection schemes for recently proposed quadrature spatial modulation (QSM) systems. The antenna selection strategy is based on Euclidean distance optimized antenna selection (EDAS). The symbol error rate (SER) performance of these schemes is compared with that of the corresponding algorithm associated with spatial modulation (SM) systems. It is shown through simulations that QSM systems using EDAS offer significant improvement in terms of SER performance over SM systems with EDAS. Their SER performance gains are seen to be about 2 dB-4 dB in $E_s/N_0$ values.

• Journal of Engineering Education Research
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• v.18 no.2
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• pp.33-42
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• 2015

The shortage of R&D personnel and the lower productivity of SMEs are critical issues in strengthening SMEs. Government provides various policies to deal with these issues. The aim of this paper is to analyze current status and policy issues of R&D personnel and to suggest policy alternatives to improve the availability of R&D personnel in SMEs.

• Proceedings of the KIEE Conference
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• 1990.11a
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• pp.278-282
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• 1990

In this paper, two different plusewidth modulation(PWM) for inverter and voltage control technique are described. Inverter output harmonics are harmful in induction motor drive because it lead to ripple torque and induction interference. In order to reduce or minimize losses, various forms of PWM strategy such as PM(Positive Modulation) and NM(Negative Modulation) are discussed.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.432-435
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• 1997

This Paper proposes a novel sinusoidal converter which improves input power factor and input current waveform without any complicated switching modulation such as a pulse width modulation or a complicated feed-back control. It is composed of a full bridge diode, a pair of capacitors, a pair of inductors and a pair of switching devices. The configuration and control strategy are both simple however, the sinusoidal converter effectively reduces reactive power and hamonics included in a input line current. Excellent behavior of the proposed converter is verified by theoretical analysis and experimental results.

• Journal of KSNVE
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• v.4 no.3
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• pp.327-335
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• 1994

In this paper, to identify the dynamic characteristics of antenna system, the antenna is divided into 4 components and those were analyzed with a conventional FEM package MSC/NASTRAN. Using a Component Mode Synthesis Method, dynamic characteristics of total system is also identified. The Coherence of each component to total system is evaluated by using strain and kinetic component to total system is evaluated by using strain and kinetic energy. The improving strategy of dynamic characteristics is suggested by changing mass and stiffness of large coherence components.

• Journal of Korean Society for Quality Management
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• v.28 no.3
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• pp.114-123
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• 2000

Six Sigma has been adopted as a major improvement initiative by some leading Korean companies. The paradigm of how statistics is to be applied in business and industry has been challenged by Six Sigma. In this paper, Six Sigma initiative and its importance are stressed. Also statistical thinking plays a major role in Six Sigma. Therefore, its relationship with Six Sigma is explained. Next, various strategies for achieving Six Sigma are reviewed. Finally the strategy that GE takes for achieving Six Sigma is examined.

• Journal of Distribution Science
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• v.3 no.2
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• pp.57-75
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• 2005

By the research seen by examining plan which can improve at least systematization of a distribution sector, reform opening got into stride to Chinese distribution channel structure by improvement of a premodern Chinese circulation system and non-efficiency-structure. The competition means of the China distribution industry, the development direction, and the Chinese distribution channel strategy are received focusing on the 1990s, and it is going to show a way proposal.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.437-440
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• 2003

본 논문은 P2P 네트워크에서 어플리케이션 레벨의 영속성있는 저장 시스템에 대해서 살펴본다. 인터넷 클라이언트의 성능 향상과 인터넷 접속 기술의 발달로 Peer-to-Peer (P2P)라는 키워드로 대표되는 다양한 파일 저장, 검색, 공유 어플리케이션이 소개되었다. 그러나, 기존의 서버 기반의 분산 저장 방식은 xDSL 기반의 가변 IP 기반의 현재 인터넷 환경에서 불안정한 성능을 보이고, 파일을 저장하고 나서 검색 발견의 확률이 떨어지는 문제점을 가진다. 본 논문에서는 시스템의 가용성(Availability)을 높이기 위한 파일의 분할 저장, 중복 저장 방법을 소개하고 이의 효과를 분석해 보인다.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.250-253
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• 2000

We researched effects of growth on initial inoculum size, liquid volume, and medium feeding rate etc. Cell suspension inoculated at low cell concentrations showed a typical growth reduction, whereas root cultures showed an improvement in growth. In this paper, Hairy roots showed high growth rate at 0.4 % inoculum size and 100 mL liquid volume in 250 mL flask cultures.

• Journal of Information Technology Applications and Management
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• v.11 no.1
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• pp.101-115
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• 2004

The goal of this research is to improve SLA index that measures service performance level as a result of outsourcing Information system, and also to identify the best application method. This research identifies SLA applied cases and improving points based on the evidence collected from three major financial institutions that utilized outsourcing. First this study analyzes SLA applied cases of two different companies and discusses SLA application improvement possibilities. It then introduces a successful case of a third company that adopted SLA index.