• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.3
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• pp.15-25
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• 2005

Ninety tow percent of over 1,800 gate controlled dams in Korea are classified as small dams. The primary purpose of these small dams is to supply irrigation water. Therefore, while large dams can store as much as 80 percent of precipitation and thus are efficient to control flood, small dams are often lack of flood control function resulting in increased susceptibility drought and flood events. The purpose of this study is to develope a storage management model for irrigation dams occupying the largest portion of small dams. The proposed Storage Management Model (STMM) can be applied to the Seongju dam for efficient management. Besides, the operation standard is capable of analyzing additional available water, considering water demand and supply conditions of watershed realistically. And the model can improve the flood control capacity and water utilization efficiency by the flexible operation of storage space. Consequently, if the small dams are managed by the proposed Storage management model, it is possible to maximize water resources securance and minimize drought and flood damages.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.3
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• pp.50-64
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• 2011

In this paper, a DC-coupled photovoltaic (PV), fuel cell (FC) and ultracapacitor hybrid power system is studied for building microgrid. In this proposed system, the PV system provides electric energy to the electrolyzer to produce hydrogen for future use and transfer to the load side, if possible. Whenever the PV system cannot completely meet load demands, the FC system provides power to meet the remaining load. The main weak point of the FC system is slow dynamics, because the power slope is limited to prevent fuel starvation problems, improve performance and increase lifetime. A power management and control algorithm is proposed for the hybrid power system by taking into account the characteristics of each power source. The main works of this paper are hybridization of alternate energy sources with FC systems using long and short storage strategies to build an autonomous system with pragmatic design, and a dynamic model proposed for a PV/FC/UC bank hybrid power generation system. A simulation model for the hybrid power system has been developed using Matlab/Simulink, SimPowerSystems and Matlab/Stateflow. The system performance under the different scenarios has been verified by carrying out simulation studies using a practical load demand profile, hybrid power management and control, and real weather data.

• Journal of the Korea Society of Computer and Information
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• v.7 no.4
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• pp.133-140
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• 2002

Distributed-queue Dual-Bus (DQDB) shows an unfair behavior in bandwidth allocation due to the nature of unidirectional bus architecture. The study on fairness control method for DQDB has been performed under specific load types such as equal Probability load. symmetric load and asymmetric load type. A client-server load type is more practical traffic pattern than specific load type in Web environments. In this paper, we propose an effective fairness control method to distribute DQDB network bandwidth fairly to all stations under Web environments. The proposed method directly calculates an access limit from the bandwidth demand pattern. Based on an access limit, it controls the allocation of bandwidth by yielding empty slots in clients to servers. And we were certain that it outperforms other mechanisms from simulation results.

• Journal of Ocean Engineering and Technology
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• v.13 no.3B
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• pp.38-46
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• 1999

Increasing stringent emissions legislation and requirement of more effective energy used for diesel engine demand the fine control of the fuel injection system. Recently, the electromagnetic fuel injection control system for diesel engine is tried to realize the optimum diesel combustion by the feel back sensing as optical signal of combustion flame. The photo detectors were made for the feed back signal of electromagnetic fuel injection control for small DI diesel engine. Their abilities to detect defining combustion events were examined. By evaluating test results, it was shown that the wider acceptable optical range design of optical probe window face, and selection of installation position and installation method of detector were important point for improving sensing ability. The detector was shown to detect start and end of diffused combustion and maximum point of flame intensity impossible for pressure sensor, and also shown that the maximum point of flame intensity was 75% of accumulated heat release point within the experimental conditions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2129-2136
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• 2012

With the increased demand of ubiquitous home services, intelligent robots have wide attentions. This kind of robots offer various services through middleware components which can connect with remote servers. In this paper we present an UPnP(Universal Plug and Play) based open-source software framework which makes control the robots remotely. This UPnP architecture for home networking can provide various communication methodologies like command control, eventing, presentation with web services and so on. This paper shows successful implementation results on two real platforms.

• Fire Science and Engineering
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• v.25 no.5
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• pp.32-38
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• 2011

Amphibious possible, and good fuel economy, so as leisure and transport has increased the use of hovercraft. Fire started in Korea, the prevalence is increasing in demand as the trend has been increasing steadily. In this paper, the hovercraft's forward and backward direction can be controlled in order to free the reverse bucket control system was developed. Control due to development by promoting the flow of air and turn right, turn left and easy to reverse the life-saving and stable at high speed, etc. has made possible the operation of hovercraft. The controller for the stability and fast response Fuzzy-PID method was used. To prove the validity of the proposed controller in Matlab simulation and the actual delivery at the firehouse, built into a model for the demonstration test was performed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.5
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• pp.888-908
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• 2011

The increasing demand from passengers in vehicles to improve safety, traffic efficiency, and comfort has lead to the growing interest of Wi-Fi based vehicle-to-infrastructure (V2I) communications. Although the V2I system provides fast and cost-effective Internet connectivity to vehicles via roadside Wi-Fi access points (APs), it suffers from frequent handoffs due to the high mobility of vehicles and the limited coverage of Wi-Fi APs. Recently, the Mobile AP (MAP) platform has emerged as a promising solution that overcomes the problem in the V2I systems. The main advantage is that MAPs may yield longer service duration to the nearby vehicles that have similar mobility patterns, yet they provide smaller link capacities than the roadside APs. In this paper, we present a new association control technique that harnesses available connection duration as well as achievable link bandwidth in high-speed vehicular network environments. We also analyze the tradeoff between two association metrics, namely, available connection duration and achievable link bandwidth. Extensive simulation studies based on real traces demonstrate that our scheme significantly outperforms the previous methods.

• Journal of Korean Institute of Industrial Engineers
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• v.3 no.1
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• pp.39-47
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• 1977

Most of the current literature on inventory theory has been devoted to the study of single stage models. A class of inventory problems which is of great interest is the multistage inventory system which involves a series and hierarchical sequence of stations. This study analyzes some aspect of the series type and multi-stage inventory system, using the fixed cycle ordering which bas a modificatory control function in the system equations. The objective of this study is to clarify the dynamic behavior of the system. The author has derived the theoretical formulas of variation of ordering quantity and stock fluctuation of each stage due to power spectral density function. Influence of parameters such as, (1) intensity of autocorrelation of demand sequence ($\lambda$), (2) forecasting exponential smoothing factors of each stage (${\alpha}_1,\;{\alpha}_2,\;{\alpha}_3$) and (3) production control factor of the 3rd stage ($\gamma$), as operators of the system on the variation of ordering quantity and stock fluctuation of the system. is also clarified. As a result of this study, the relations between the variation of ordering quantity, stock fluctuation and the parameters of the system, have been found. The principles and the theorical analysis presented here will be applicable to more complex type of discrete control systems in constructing the specific condition of the system to minimize inventory variances.

• Interdisciplinary Bio Central
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• v.2 no.4
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• pp.15.1-15.5
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• 2010

RIKEN BioResource Center (BRC) has collected, preserved, conducted quality control of, and distributed mouse resources since 2002 as the core facility of the National BioResource Project by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. Our mouse resources include over 5,000 strains such as humanized disease models, fluorescent reporters, and knockout mice. We have developed novel mouse strains such as tissue-specific Cre-drivers and optogenetic strains that are in high demand by the research community. We have removed all our specified pathogens from the deposited mice and used our quality control tests to examine their genetic modifications and backgrounds. RIKEN BRC is a founding member of the Federation of International Mouse Resources and the Asian Mouse Mutagenesis and Resource Association, and provides mouse resources to the one-stop International Mouse Strain Resource database. RIKEN BRC also participates in the International Gene Trap Consortium, having registered 713 gene-trap clones and their sequences in a public library, and is an advisory member of the CREATE (Coordination of resources for conditional expression of mutated mouse alleles) consortium which represents major European and international mouse database holders for the integration and dissemination of Cre-driver strains. RIKEN BRC provides training courses in the use of advanced technologies for the quality control and cryopreservation of mouse strains to promote the effective use of mouse resources worldwide.

• Journal of Korea Multimedia Society
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• v.18 no.2
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• pp.189-198
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• 2015

Despite the fact that traffic engineering techniques have been comprehensively utilized in the past to enhance the performance of communication networks, the distinctive characteristics of Software Defined Networking (SDN) demand new traffic engineering techniques for better traffic control and management. Considering the behavior of traffic, large flows normally carry out transfers of large blocks of data and are naturally packet latency insensitive. However, small flows are often latency-sensitive. Without intelligent traffic engineering, these small flows may be blocked in the same queue behind megabytes of file transfer traffic. So it is very important to identify large flows for different applications. In the scope of this paper, we present an approach to detect large flows in real-time without even a short delay. After the detection of large flows, the next problem is how to control these large flows effectively and prevent network jam. In order to address this issue, we propose an approach in which when the controller is enabled, the large flow is mitigated the moment it hits the predefined threshold value in the control application. This real-time detection, marking, and controlling of large flows will assure an optimize usage of an overall network.