• Convergence Security Journal
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• v.13 no.3
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• pp.17-23
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• 2013

Clustering is required to configure clustering interdependent structural technology. Clustering handles variable workloads or impede continuity of service to continue operating in the event of a failure. Long as high-availability clustering feature focuses on server operating systems. Active-standby state of two systems when the active server fails, all services are running on the standby server, it takes the service. This function switching or switchover is called failover. Long as high-availability clustering feature focuses on server operating systems. The cluster node that is running on multiple systems and services have to duplicate each other so you can keep track of. In the event of a node failure within a few seconds the second node, the node shall perform the duties broken. Structure for high-availability clustering efficiency should be measured. System performance of infrastructure systems performance, latency, response time, CPU load factor(CPU utilization), CPU processes on the system (system process) channels are represented.

• International Commerce and Information Review
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• v.11 no.3
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• pp.125-144
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• 2009

The purpose of this study is to research the investment environment of Vietnam and analyze the actual investment state of Korean enterprises in Vietnam and seek for the points at issue. In general, the investment environment in Vietnam shows both a positive side and negative side. However Vietnamese market is a attractive one as ever for direct investment of Korean enterprises considering their constant economy growth, investment increase of foreign company for Vietnam, China risk. And the point at issue in investment of Korean Enterprises is as follows. That is, inclining to manufacturing, preference of independence investment, small-sized investment by small and medium enterprises, preference of greenfield investment, restricted purpose of investment, insufficiency of infrastructure for logistics, electric power, legal system. The results of the study indicate mainly that the investment of Korean enterprise into Vietnam needs a switchover of the third service trade-tertiary industry, collaboration with Vietnamese enterprise through joint venture investment, a large-scale investment for Vietnam domestic market and neighboring countries' market, practical use of M&A with existing Vietnamese enterprise and diverse purpose for investment.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2795-2798
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• 2003

본 논문에서는 국내에서 개발하고 있는 과학로켓용 발사통제시스템(FCS, Fire Control System)의 시퀀스제어의 처리 영역을 PLC 시스템을 사용하여 구현하였다. 프로세서의 이중화를 통하여 Hot Backup 시스템을 구축하고 ControlNet 네트워크［l］［2］를 기반으로 하는 프로세서와 I/O 간의 통신을 이용하였다. 먼저 로켓 발사통제시스템의 개요 및 주요 임무에 대하여 설명하고 기존에 사용된 발사통제시스템 구성을 분석하였다. PLC 시스템의 개요와 CPU 동작 내용 그리고 ControlNet 통신방식에 대하여 설명하고 프로세서를 이중화한 시스템을 제안하였다. 또한 이중화된 프로세서의 Switchover［2］방법을 알아보고 이러한 조건에 따른 PLC 시스템을 응용한 발사 통제시스템을 구성하여 이를 위해 작성된 시스템 운용 Ladder Diagram 프로그램에 대한 기술을 논하였다. 개발된 PLC 시스템의 구성을 제시하고 발사체 및 각종 지원시설과 연계한 시험을 통하여 성능을 검증하였다.

• Journal of Industrial Technology
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• v.17
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• pp.79-85
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• 1997

This paper describes a control for the high performance induction motor drive system with a wide speed operating range and proposes a robust control method independent of motor parameter variation. For the operation below the rated speed, the high performance control is achieved by using the indirect field-oriented control with a speed sensor. In the high speed regain, the field weakening region with a large variation in motor parameters, the motor drive system can obtain the robustness to motor parameter variation by switchover to the direct field-oriented control. Also, the sensorless speed control using estimated speed is achieved in very high speed region that the utilization of speed sensor pulses is limited. And from experiments using high performance 32bit DSP for 2.2[kW] and 22[kW] laboratory induction motor drive systems, it is verified that the proposed opration algorithm provided a good performance.

• Advances in Energy Research
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• v.5 no.4
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• pp.305-320
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• 2017

Limited quantity and non-uniform distribution of fossil fuel over the world, along with the environmental concerns of increasing $CO_2$ emissions, indicate that gradual and planned switchover to the sustainable energy sources is the need of the day. Ocean energy is well-distributed over the coasts, abundant, renewable and available in the form of wave energy, tidal energy and thermal energy. India has gathered precious experience from the pilot plants utilizing these methods over the last few years. One of the main constraints is deemed to be the grid connectivity. Time has come to transform this limitation into opportunity. Ocean power can be a very suitable option for the coastal belts and the islands. Implementation of this concept would require large-scale industry participation along with favourable government policies in the coming years. This article attempts a review of the ocean energy initiatives in India and proposes a roadmap for the future.

• The KIPS Transactions:PartC
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• v.8C no.2
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• pp.173-181
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• 2001

하드웨어 기술의 발전으로 인해 컴퓨터 하드웨어의 결함 발생률은 상수 값이거나 점차 작아지는 경향이 있다. 반면에 하드웨어에 탑재된 소프트웨어의 복잡성 및 크기는 이전에는 상상할 수 없을 정도로 방대해져가고 있기 때문에, 소프트웨어의 결함 발생으로 인한 컴퓨터 시스템의 장애 발생 가능성은 점차 더 높아지고 있다. 본 논문에서는 Active/Active 클러스터 시스템의 가용도 개선을 위해서 소프트웨어적인 결함 발생을 미연에 방지할 수 있는 능동적 결함허용 기법인 소프트웨어 재활(rejuvenation) 방법에 대하여 연구하였다. 소프트웨어 재활 과정 및 여분서버로 작업전이(switchover) 과정을 semi-Markov 프로세스로 모델링 한 후, 수학적 분석을 통해 구한 Active/Active 클러스터 시스템의 bud형 상태 확률을 이용하여, 다양한 운영 조건하의 가용도 및 손실비용을 계산하였으며, 이를 통하여 소프트웨어 재활을 통한 Active/Active 클러스터 시스템의 가용도 개선 가능성을 확인하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.18-28
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• 2005

인터넷 사용자의 증가와 함께 전자상거래가 활성화되면서 그 성공요인을 규명하고자 하는 노력은 계속 되고 있다. 특히 정보기술의 발달로 서비스의 온라인 거래가 가능해지고 있고 그 비중 또한 증대되고 있으나 아직까지 온라인에서의 서비스에만 초점을 맞춘 연구는 제한적이다. 따라서 본 연구는 전자상거래에서 거래되는 서비스에 대한 고객의 인식을 바탕으로 서비스의 오프라인 대비 온라인 선호에 영향을 미치는 요인들을 규명하고자 한다. 이를 위해 현재 국내 포탈에서 제공되는 서비스를 대상으로 고객설문을 수행하였으며 수집된 자료를 활용하여 온라인 선호에 대한 로지스틱 회귀분석을 실시하였다. 제안된 모형은 순수 오프라인에서 제공되는 서비스의 일부를 온라인 서비스로 전환하고자 할 때 고려해야 하는 요소들이 무엇이며 그 성공가능성을 예측할 수 있도록 도와줄 것으로 기대된다.

• Journal of Korean Society for Quality Management
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• v.32 no.4
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• pp.196-207
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• 2004

TDR(Tear Down & Redesign)means that renounce the past resolutely, from a white paper condition, let's change directions. That is, let's redesign from the basic of the establishment of the construction process. Through the switchover the conception, innovate totally the whole existing processes. TDR is the best core innovation activity. The ultimate aim of the TDR activity induces the employees to do more productive business and obtain excellent results in the future by solving the problems, which are the nonproductive business in the business process on the objective view, the business that customers don't recognize the value, the same old practice of business, and the unsettled business from the restriction of resources. By organizing the related to workers of those business, they can solve the problems for 3-4months by full time working This paper inquires what are the obstruction factors on the process of executing TDR activity. Through the search of the reformation plan for the improvement of immersion degree, it presents some methods to be successful business.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.7
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• pp.76-91
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• 1996

In this paper, we proposed the new medium access control protocol for the virtual token bus netowrk. The network is applied to inter-processor communication network of large capacity digital switching system and digital mobile system with distributed control architecture. in the virtual token bus netowrk, the existing medium access control protocols hav ea switchove rtime overhead when traffic load is light or asymmetric according ot arbitration address of node that has message to send. The proposed protocol optimized average message delay using cyclic bus access chain to exclude switchover time of node that do not have message to send. Therefore it enhanced bus tuilization and average message delay that degrades the performance of real time communication netowrks. It showed that the proposed protocol is more enhacned than virtual token medium access control protocol and virtual token medium access control protocol iwth reservation through performance analysis.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.140.4-140
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• 2001

This paper presents the duplex controller operated as master slave for Self Excited Static Type excitation system and the results of operation for duplex digital excitation system. Software is made up duplex multi-tasking control algorithm which is based on VxWorks(real-time OS), preprocessing algorithm for input-output signal, BSP & Device Driver for interfacing hardware and software, and OIS(Operator Interface Station) program, HMI S/W. Master controller and slave controller intercommunicate dominant data to minimize bump when controller switchover from master to slave occurs. Communication between master controller and slave controller is duplicated and communication between OIS and controller is duplicated. Hardware is made up VMEBUS based controller which is designed with PPC & I/O board ...