• Journal of Information Processing Systems
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• v.10 no.4
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• pp.628-645
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• 2014

In past few years, distributed hash table (DHT)-based P2P systems have been proven to be a promising way to manage decentralized index information and provide efficient lookup services. However, the skewness of users' preferences regarding keywords contained in a multi-keyword query causes a query load imbalance that combines both routing and response load. This imbalance means long file retrieval latency that negatively influences the overall system performance. Although index replication has a great potential for alleviating this problem, existing schemes did not explicitly address it or incurred high cost. To overcome this issue, we propose, in this paper, an integrated solution that consists of three replication schemes to alleviate query load imbalance while minimizing the cost. The first scheme is an active index replication that is used in order to decrease routing load in the system and to distribute response load of an index among peers that store replicas of the index. The second scheme is a proactive pointer replication that places location information of each index to a predetermined number of peers for reducing maintenance cost between the index and its replicas. The third scheme is a passive index replication that guarantees the maximum query load of peers. The result of simulations indicates that the proposed schemes can help alleviate the query load imbalance of peers. Moreover, it was found by comparison that our schemes are more cost-effective on placing replicas than PCache and EAD.

• Journal of Information Processing Systems
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• v.17 no.1
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• pp.191-202
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• 2021

In an Internet of Things (IoT)-configured system, each device executes on-chip software. Recent IoT devices require fast execution time of complex services, such as analyzing a large amount of data, while maintaining low-power computation. As service complexity increases, the service requires high-performance computing and more space for embedded space. However, the low performance of IoT edge devices and their small memory size can hinder the complex and diverse operations of IoT services. In this paper, we propose a remote on-demand software code execution unit using the cloudification of on-chip code memory to accelerate the program execution of an IoT edge device with a low-performance processor. We propose a simulation approach to distribute remote code executed on the server side and on the edge side according to the program's computational and communicational needs. Our on-demand remote code execution unit simulation platform, which includes an instruction set simulator based on 16-bit ARM Thumb instruction set architecture, successfully emulates the architectural behavior of on-chip flash memory, enabling embedded devices to accelerate and execute software using remote execution code in the IoT environment.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1103-1106
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• 2008

Data Grid is a kind of Grid computing provides the cooperative environment through the distributed data sharing, and can manage the massive data easily and efficiently. We designed and implemented Globus Toolkit4 (GT4) based database access and integration service (GDAIS). This service was implemented as Grid service for run on the GT4 which is Grid middleware. And it provides functions which are automatic registration of database in virtual organization, distributed query service, and the unified user interface. Also this system can use components which are provided from GT4. Therefore it can improve the efficiency to distribute and manage databases, can easily access and integrate of the distributed heterogeneous data in Grid environments.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.830-832
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• 2008

변전설비 감시제어시스템은 그 목적상 실시간의 대규모 측정정보 취득을 목적으로 한다. 취득정보는 RTU(Remote Terminal Unit)를 통해서 감시제어시스템에 전달된 후 필요에 따라 해당 정보를 요청하는 애플리케이션들에게 다시 전송된다. 현재 감시제어시스템에 널리 사용되는 DNP(Distribute Network Protocol)는 취득포인트 정보와 취득값만 가지고 있으므로 포인트 리스트에 대한 정보가 없는 경우에는 취득한 데이터를 판독할 수 없다. 따라서 감시제어시스템을 구축하기 위해 우선 RTU에 감시 선로정보를 입력하고, 이 정보를 다시 감시제어시스템의 DB에 포인트 정보와 매핑을 수행해야만 한다. 또한, 새로운 애플리케이션에서 취득값을 얻기 위해서는 이들 포인트 정보와 매핑 정보를 가지고 있는 감시제어시스템의 DB에 직접 연결해야만 한다. 본 논문은 공통정보모델과 이를 기반으로 작성된 메시지 교환 표준 인터페이스를 이용하여 감시제어시스템 취득정보의 효과적인 교환이 가능한 메시지 통합버스에 대하여 기술한다.

• Proceedings of the KSRS Conference
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• v.1
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• pp.75-78
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• 2006

The Korea Ocean Satellite Center (KOSC) is under development to establish in line with the launch of the first Korean multi-function geostationary satellite COMS (Communication, Ocean and Meteorological Satellite) scheduled in 2008. KOSC aims to receive, process and distribute Geostationary Ocean Color Sensor (GOCI) data on board COMS in near-real time. In this report, current status of KOSC development is presented in the following categories; site selection for KOSC, antenna design, GOCI data receiving and processing system, data distribution, future works.

• Transactions of Materials Processing
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• v.13 no.8
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• pp.671-677
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• 2004

For the large reduction in tube cross section, the tube drawing process is usually performed by two successive passes, so called first drawing and second drawing. In multi-pass drawing process, the reduction balance is important to prevent drawing cracks. Therefore in this study, the model for uniform reduction distribution in two-pass drawing process has been developed on the basis of cross sectional variation of drawn tube. For the given product geometry the model provides optimal diameter and thickness that can evenly distribute drawing reductions. The capability of model is well confirmed by finite element analysis of tube drawing process. Criteria curves at various limit strains to determine whether the drawn tube would fail during drawing process are also proposed by using newly developed model.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.113-116
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• 2003

In this paper, we propose a dynamic parallel channel allocation mechanism that dynamically controls total number of allocation channels of each subscriber to effectively service user bandwidth demands while high utilization and fairness are guaranteed in WDM based optical access networks. The logical performance gain of statistical multiplexing by dynamic channel allocation is validated with analytic method as well as simulations. We also introduce the adaptive padding scheme in order to efficiently distribute forwarded frames to aggregated multi-link channels which are formed by parallel channel allocation mechanism. The proposed scheme shows the performance enhancement by minimizing unnecessary padding size and the processing time.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.382-387
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• 2005

There are many studies on arbitrarily divisible load scheduling problem in a distributed computing network consisting of processors interconnected through communication links. It is not efficient to arbitrarily distribute the load that comes into the system. In this paper, how to schedule in case that arbitrarily indivisible load comes into the system is studied. Also, the cases of the divisible load mixed with the indivisible load that come into network were dealt with optimal load distribution in parallel processing system by scheduling applied to linear programming.

• The KIPS Transactions:PartA
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• v.10A no.3
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• pp.225-230
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• 2003

In this paper, we develope algorithms that distribute the load on the heterogeneously clustered web system, The response time based on the concurrent user is examined for the suggested algorithms. Simulation experience shows that the response time using the dynamically weighted methods seems to have a good results compare to that with the fixed weighted methods. And, also the effectiveness of clustered system becomes better as long as the number of concurrent user increases.

• International Journal of Computer Science & Network Security
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• v.23 no.2
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• pp.227-236
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• 2023

The research aims to identify the degree of the organizational citizenship, satisfaction and performance quality of the teachers and relationship between organizational citizenship, job satisfaction and performance quality for physical education teachers . The researcher used the descriptive method, The participants were (195) teachers. The researcher conducted the research main study in the period from 05/12/2022 to 30/12/2022 use the website to distribute and collect the questionnaire: https://www.surveymonkey.com. The researcher used the computer in the statistical processing, using the SPSS statistical program, and the following methods: Mean, SD, percentages, Correlation Coefficient, Alpha Cronbach coefficient, differences Indicator using chi² . Conclusions: There is high degree of organizational citizenship behavior practices, job satisfaction and performance quality for some teachers at the schools. Recommendation the importance of enhancing the organizational citizenship behavior in schools, according to the positive effects of these behaviors on the individual and group performances.