• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.3
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• pp.354-361
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• 2014

The Unified Power Flow Controller (UPFC) can flexibly manage power flow and maintain line voltage. The UPFC consists of two inverters in parallel side and series side. In parallel side, the reactive power can be compensated to improve the power factor. In series side, the voltage drop can be compensated to maintain proper line voltage. It is necessary for the operation in both sides to output the current and the voltage quickly and accurately. As the method for the UPFC control, the deadbeat control with state observer is applied. The deadbeat control is able to realize a quick response of the current and voltage control for only a sampling period compared with the general PI control. A principle and simulation results are presented in this paper.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.215-217
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• 2004

In wireless sensor networks, fair allocation of bandwidth among different nodes is one of the critical problems that effects the serviceability of the entire system. Fair bandwidth allocation mechanisms, like fair queuing, usually need to maintain state, manage buffers, and perform packet scheduling on a per flow basis, and this complexity may prevent them from being cost-effectively implemented and widely deployed. It is a very important and difficult technical issue to provide packet scheduling architecture for fairness in wireless sensor networks. In this paper, we propose an packet scheduling architecture for sensor node, called FISN (Fairness Improvement Sensor Network), that significantly reduces this implementation complexity yet still achieves approximately fair bandwidth allocations. Sensor node for sensing estimate the incoming rate of each sensor device and insert a label into each transmission packet header based on this estimate. Sensor node for forwarding maintain no per flow state; they use FIFO packet scheduling augmented by a probabilistic dropping algorithm that uses the packet labels and an estimate of the aggregate traffic at the gathering node. We present the detailed design, implementation, and evaluation of FISN using simulation. We discuss the fairness improvement and practical engineering challenges of implementing FISN in an experimental sensor network test bed based on ns-2.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1501-1518
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• 2016

This paper presents an effective management of VM (Virtual Machine) for heterogeneous cloud using Common Deployment Model (CDM) brokering mechanism. The effective utilization of VM is achieved by means of task scheduling with VM placement technique. The placements of VM for the physical machine are analyzed with respect to execution time of the task. The idle time of the VMis utilized productively in order to improve the performance. The VMs are also scheduled to maintain the state of the current VM after the task completion. CDM based algorithm maintains two directories namely Active Directory (AD) and Passive Directory (PD). These directories maintain VM with proper configuration mapping of the physical machines to perform two operations namely VM migration and VM roll back. VM migration operation is performed from AD to PD whereas VM roll back operation is performed from PD to AD. The main objectives of the proposed algorithm is to manage the VM's idle time effectively and to maximize the utilization of resources at the data center. The VM placement and VM scheduling algorithms are analyzed in various dimensions of the cloud and the results are compared with iCanCloud model.

• Women's Health Nursing
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• v.25 no.1
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• pp.73-85
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• 2019

Purpose: To determine whether maternal attitude toward sex during pregnancy and health-related quality of life could influence sexual function of pregnant women. Methods: In this study, 138 second and third trimester pregnant women completed self-report questionnaires during their visits to women's hospitals or community health centers to assess their general characteristics, attitude toward sex during pregnancy (PIES-M), health-related quality of life (EQ-5D), and sexual function (FSFI-6K). Multiple regression analysis was performed to test the research model with SPSS version 23. Results: Pregnant women who had discontinued their sexual life after recognizing their pregnancy accounted for 27.5% of women questioned. The average sexual function score of pregnant women was higher in the second trimester than the third trimester. Attitude toward sex during pregnancy (${\beta}=-.38$, p<.001), maintaining sexual life (${\beta}=.20$, p=.028), health-related quality of life (${\beta}=.18$, p=.030), and adverse symptoms during sex (${\beta}=.18$, p=.042) were determinants of sexual function during pregnancy. Conclusion: Nurses in antenatal care units need to help pregnant women maintain a positive attitude toward sexual activity during pregnancy and manage their health-related quality of life to maintain their sexual life during pregnancy.

• Convergence Security Journal
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• v.16 no.3_1
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• pp.77-85
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• 2016

Integrated logistics support activities is to comprehensively manage the logistic support elements in the whole pro cess, from the design, development, acquisition request from the time it takes, operating and disposal for the efficient and cost-effective logistics support equipment. In other words, maintain the performance of the weapon system, and is required to be filed from the time the economic comprehensive logistic support until discarded activities, managing all logistic support throughout the life cycle period. This study was an intensive study for a seamless integrated logistics support force support system, the result wa s determined that the insufficient number of parts to the weapons sector, presents some development direction for se amless integrated logistics support force support system and should.

• The Transactions of the Korea Information Processing Society
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• v.3 no.7
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• pp.1822-1833
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• 1996

As the size and complexity of networks increase, it is difficult to manage the whole network using single network manager, thus it is more resonable to manage the network using several network managers distributed on the network. Security interoperability should be supported among network management systems (NMSs)that use different management policies. In this paper, an algorithm that makes it posible to take a role into a role lattices is suggested to provide security interoperability among NMSs that have their own role lattices. In addition, security constraints are proposed to maintain the confidentiality and integrity of information by dynamically modifying the access rights of roles as the state of a system changes. Also, the security constraints are expressed using ECA rules in this paper.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.2
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• pp.69-77
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• 2004

Now, there are some problems to manage underground facilities in domestic. Specially, in the case of KEPCO(Korea Electric Power Corporation), it is so difficult to manage electronic line more stably and detailedly because the geographic information and attribute information being built is not easy to be updated in the field. KEPCO officials who are accompanying management and supervision in earthwork do not have sufficient knowledge and information about GIS but they grasp the information of geography and property which coincide with the field. Therefore they have to refer their business analysis contents sufficiently for more efficient lines management in the KEPCO, but it is problem that the existing information of electronic lines management system is not. In this study, we constructed power transmission and power distribution underground facility management system for the user to manage and maintain underground facilities more easily and safely using the information of geography and property about power transmission and power distribution underground facility which have been built by KEPCO.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1165-1172
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• 2008

A considerable amount of research has focused on the dimensionality of service quality construct. To achieve and maintain their comprehensiveness and profitability, restaurant managers should manage and aim to continuously improve the level of service quality offered to their customers. This paper is focused on service quality in the Korean native cattle and imported beef restaurant industry in the Korea. So, this paper has adapted DINESERV scale so that restaurant managers can use it to determine how customers perceive the service quality in Korean native cattle beef restaurant and imported beef restaurant. The purpose of this research is to test the difference in importance and actual performance of 5 dimensions between the restaurants that sell the beef of Korean native cattle and imported cattle. The t-value is used to test difference of the importance and actual performance for DINESERV's 5 dimensions of the 2 restaurant types. But, there is no difference between Korean native cattle and imported beef restaurant.

• Korean Management Science Review
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• v.9 no.1
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• pp.41-52
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• 1992

The QOS(Quality of Service) recognized by the customer will become the most important thing under the competitive telecommunications market. Korea Telecom is going to develop many system to manage the telecommunication network, to improve the level of QOS, and to increase the revenue. Operation and Maintenance Adiministration System is one of the systems developed to meet those purposes efficiently. This system gathers qualities data from telephone offices or operation centers and analyze the results of QOS improvement activities and evaluate overall QOS. And also system makes it possible to improve the cost/effectiveness of operation and maintenance of telecommunication network. Operation and Maintenance Administration System has four functional modules, i.e., the user interface module, the database management module, the QOS management module, and the database conversion module. The purpose of this study is to develop the QOS management program, one of the four functional modules of the system,using FOCUS 4GL/DBMS. Since Operation and Maintenance Administration System is developed using FOCUS 4GL, every user can handle and maintain the system very easily and reduce system backlogs.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.2
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• pp.53-61
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• 2017

How to manage manhole is to estimate the part without observation and maintain the sewer. To get the information about current flow rate, visiting and measuring specific manhole is positively necessary. Also, there are some problems that accurate measurement of flow rate is difficult and obtaining the information about real-time whole flow rate is impossible. This thesis will easily grasp the accurate location and type of manhole to solve the problems, and provide the manhole system conveying information through direct radio communication with a manhole cover to renewal information of manhole properly. Besides, it intends to save the information about management of waterworks, maintenance of facilities, data for flow rate, and structure of manhole. Using these, it is supposed to offer how to handle manhole. Thus, this thesis delivers the information to manhole and into central servers directly without wire and provides the system and management method for effective maintenance of manhole.