• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.5
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• pp.724-729
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• 2008

This paper presents the calculation of the required bandwidth of common frequency bandwidth applying queueing theory for maximizing the efficiency of frequency resource of WPAN(Wireless Personal Area Network) based Digital acoustic and communication devices. It assumed that LBT device(ZigBee) and FH devices (DCP, RFID and Bluetooth) coexist in the common frequency band for WPAN based Digital acoustic and communication devices. Frequency hopping (FH) and listen before talk (LBT) have been used for interference avoidance in the short range device (SRD). The LBT system transmits data after searching for usable frequency bandwidth in the radio wave environment. However, the FH system transmits data without searching for usable frequency bandwidth. The queuing theory is employed to model the FH and LBT system, respectively. As a result, the throughput for each channel was analyzed by processing the usage frequency and the interval of service time for each channel statistically. When common frequency bandwidth is shared with SRD using 250mW, it was known that about 35 channels were required at the condition of throughput 84%, which was determined with the input condition of Gaussian distribution implying safety communication. Therefore, the common frequency bandwidth is estimated with multiplying the number of channel by the bandwidth per channel. These methodology will be useful for the efficient usage of frequency bandwidth.

• Journal of Gifted/Talented Education
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• v.26 no.2
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• pp.319-346
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• 2016

In this study, by examining the characteristics of boys and girls which would appear in the performance process of Goldberg machine activities, it would be attempted to provide the implications for the development and teaching methods of gifted and talented programs. The object of study was organized into separate 2 groups of boys and girls by each, composed of a total of 16 people among 5th graders of the gifted class in elementary school, located in Gyeonggi province. The final assignment was to make the Goldberg machine in order to have the beads get to the target spot latest, in which the analysis was implemented qualitatively by participating in and observing the performance process of students. After dividing the Goldberg machine activities into the steps of planning, production, outcome, assessment and reflection, their analysis results are as follows: First, in the planning stage, the girls explained minutely the process of Goldberg machine in writing, whereas the boys represented it visually simply. Second, in the production stage, the boys showed the task commitment by trying to realize the machine as designed initially, but the girls showed their appearance to represent it simply and easily. Third, in the sophistication and efficiency of the machine production, the boys were superior to the girls, and in the creativity and diversity of the use of materials, the girls were more excellent. Fourth, in the assessment and reflection, the boys evaluated it individually, and the girls showed their appearance to evaluate it by reflecting others'thinking. Hence, when developing and teaching the gifted and talented programs, it would be required that the teaching and learning contents be recomposed by considering the gender, or that the various class strategies be sought. Further, the broader and more systematic studies, on the performance process of gifted students based on the gender, should be carried out.

• Journal of the Korea Society of Computer and Information
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• v.17 no.1
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• pp.61-69
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• 2012

Smart Grid is the next-generation intelligent power grid that maximizes energy efficiency with the convergence of IT technologies and the existing power grid. Smart Grid is created solution for standardization and interoperability. Smart Grid industry enables consumers to check power rates in real time for active power consumption. It also enables suppliers to measure their expected power generation load, which stabilizes the operation of the power system. Smart industy was ecolved actively cause Wireless communication is being considered for AMI system and wireless communication using ZigBee sensor has been applied in various industly. In this paper, we proposed efficient addressing scheme for improving the performance of the routing algorithm using ZigBee in Smart Grid environment. A distributed address allocation scheme used an existing algorithm has wasted address space. Therefore proposing x, y coordinate axes from divide address space of 16 bit to solve this problem. Each node was reduced not only bitwise but also multi hop using the coordinate axes while routing than Cskip algorithm. I compared the performance between the standard and the proposed mechanism through the numerical analysis. Simulation verify performance about decrease averaging multi hop count that compare proposing algorithm and another. The numerical analysis results show that proposed algorithm reduce multi hop than ZigBee distributed address assignment and another.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.4
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• pp.71-81
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• 2010

In grid system, Task scheduling based on list scheduling models has showed low complexity and high efficiency in fully connected processor set environment. However, earlier schemes did not consider sufficiently the communication cost among tasks and the composition process of lightpath for communication in optical gird environment. In this thesis, we propose LSOG (Leveling Selection in Optical Grid) which sets task priority after forming a hierarchical directed acyclic graph (DAG) that is optimized in optical grid environment. To determine priorities of task assignment in the same level, proposed algorithm executes the task with biggest communication cost between itself and its predecessor. Then, it considers the shortest route for communication between tasks. This process improves communication cost in scheduling process through optimizing link resource usage in optical grid environment. We compared LSOG algorithm with conventional ELSA (Extended List Scheduling Algorithm) and SCP (Scheduled Critical Path) algorithm. We could see the enhancement in overall scheduling performance through increment in CCR value and smoothing network environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.10A
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• pp.912-921
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• 2005

Optical burst switching(OBS) is a promising solution for building terabit optical routers and realizing If over WDM. Channel scheduling Algorithm for reduce contention is one of the major challenges in OBS. We address the issue of how to provide basic burst channel scheduling in optical burst switched WDM networks with fiber delay lines(FDLs). In OBS networks the control and payload components or a burst are sent separately with a time gap. If CHP arrives to burst switch node, because using scheduling algorithm for data burst, reservation resources such as wavelength and transmit data burst without O/E/O conversion, because contention and void between burst are happened at channel scheduling process for data burst that happened the link utilization and bust drop probability Existent proposed methods are become much research to solve these problems. Propose channel scheduling algorithm that use Release Time of bust to emphasize clearance between data and data dissipation that is happened in data assignment in this treatise and maximize bust drop probability and the resources use rate (RTUC : Release Time Unscheduled Channel). As simulation results, Confirmed that is more superior in terms of data drop and link utilization than scheduling algorithm that is proposed existing. As simulation results, confirmed improved performance than scheduling algorithm that is proposed existing in terms of survival of burst, efficiency resource and delay. However, In case load were less, degradation confirmed than existent scheduling algorithm relatively, and confirmed that is superior in data drop aspect in case of load increased.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.1
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• pp.165-182
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• 2004

According to the Annex 17 to the Convention on International Civil Aviation, an appropriate authority of each contracting state has to define and allocate tasks and coordinate activities between the departments, agencies and other organizations of the State, airport and aircraft operators and other entities concerned with or responsible for the implementation of various aspects of the national civil aviation security programme. It is generally recognized that the three major parties responsible for the aviation security at an airport are appropriate government departments, airport operator and airlines. The airlines are the beneficiaries of security activities as well as the provider of security activities. So, their responsibilities have been critical in protecting civil aviation from unlawful interferences. The airport has to take leading role in implementing security tasks at airport area because the airport operator is the provider of airport facilities and services to its customer and the security activities belong to its services. The government has the responsibilities not only for establishing regulatory system but also for oversighting the implementation of aviation security activities. The paper is to review the revision of aviation security regulation and the changes of aviation security responsibilities, and costs and task assignment in Republic of Korea after September 11 event. The responsibilities, tasks and costs assigned to airlines, airport operators and government are introduced and evaluated in terms of economic fairness, effectiveness and efficiency of aviation security activities. The drawbacks of new legal system are pointed out and the suggestions to remedy them are proposed as conclusions.

• Korean Journal of Social Welfare
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• v.35
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• pp.107-131
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• 1998

This study tried to formulate and operate an interdisciplinary case management team in Eun-Pyung Gu, Seoul. This was a part of an effort to promote efficiency of service delivery system for low-income elderly or the handicapped by linking. coordinating. and integrating various health and human services providers. In-depth qualitative analysis described the process of which the interdisciplinary case management team was formed, along with the process of the team operation. The interdisciplinary team consisted of home helpers, visiting nurses, and social workers from Health Center and Social Welfare Centers. Issues dealt with by the team include: 1) information exchange of clients' social, economic, and medical situations; 2) identification of types of service provision to clients; 3) clients' needs assessment and its prioritization; 4) assignment of a leading case manager for each case; 5) identification of problems and issues regarding integration of service delivery system The team approach to case management contributed to the systematic delivery of services to the elderly and the handicapped by avoiding service duplication and fragmentation. This study argued that public agency played a key role in constituting and operating the interdisciplinary case management team Suggestions for further studies were presented.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.6
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• pp.187-193
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• 2015

The ICT healing platform sets a couple of goals including preventing chronic diseases and sending out early disease warnings based on personal information such as bio-signals and life habits. The 2-step open system(TOS) had a relay designed between the healing platform and the storage of personal health data. It also took into account a publish/subscribe(pub/sub) service based on large-scale connections to transmit(monitor) the data processing process in real time. In the early design of TOS pub/sub, however, the same buffers were allocated regardless of connection idling and type of message in order to encode connection messages into a deflate algorithm. Proposed in this study, the dynamic buffer allocation was performed as follows: the message transmission type of each connection was first put to queuing; each queue was extracted for its feature, computed, and converted into vector through tf-idf, then being entered into a k-means cluster and forming a cluster; connections categorized under a certain cluster would re-allocate the resources according to the resource table of the cluster; the centroid of each cluster would select a queuing pattern to represent the cluster in advance and present it as a resource reference table(encoding efficiency by the buffer sizes); and the proposed design would perform trade-off between the calculation resources and the network bandwidth for cluster and feature calculations to efficiently allocate the encoding buffer resources of TOS to the network connections, thus contributing to the increased tps(number of real-time data processing and monitoring connections per unit hour) of TOS.

• The Journal of Fisheries Business Administration
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• v.36 no.3 s.69
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• pp.119-139
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• 2005

The purpose of this paper is to provide information that will help both fishing industry and fisheries authority understand the principals of individual transferable quota(ITQ) fishery management. Theoretical frameworks and primary features of ITQ fishery managemenet are the assignment of exclusive property rights for harvest of common - property fisheries resources. An ITQ fishery management is fundamentally different from the conventional fishery management and it gives an individual fisherman the right to catch a specified quantity of fish, his quota. With ITQ, fisherman's quotas are transferable, in whole or in part. An ITQ is a property with certain rights of use, namely, the right to catch a given quantity and species of fish in a specific location during a specific period of time. The right is exclusive in the sense that no one else has the right to use the quota without the owner's permission. The property may be assigned, traded, and exchanged; i.e., the owner has the right to transfer an ownership to others. An ITQ fishery management leads to both economic efficiency and resource conservation. Motivations to overexploit stocks and to overcapitalize should be lessened because fishermen no longer have to compete for limited resources. There are significant positive net benefits and advantages with ITQ fishery management than without. The potential benefits and advantages of ITQ fishery management include increased profits, economic stability, improved product quality, safer working conditions, less gear conflict, elimination of the race - to - fish phenomenon, less by - catch, less gear loss, improved investment climate, mitigation of market gluts, waste reduction, addition to fisherman's wealth, and compensation for fisherman exiting the fishery. As an independent observe to Red Crab Trap Fishery some of the benefits, problems, and effects, an ITQ fishery management in Red Crab Trap Fishery is still far from to be implemented. Many different and difficult aspects (biological, socioeconomics, administrative) are involved considering the implementation of ITQ fishery management in Red Crab Trap Fishery. Among other fishery management tools, the implementation of ITQ fishery management in Red Crab Trap Fishery is considered to be the best in achieving the better conservation of fisheries resources and their more economic and rational exploitation. Korean fisheries authority should pay great attention to the experience of the economic effects of the ITQ fishery management in Red Crab Trap Fishery in the hope of being able to implement at least some of those experiences into the Korean fishery management.

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.81-89
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• 2011

Underwater wireless network can be useful in various fields such as underwater environment observation, catastrophe prevention, ocean resources exploration, ocean organism research, and vessel sinking exploration. We need to develop an efficient design for Medium Access Control (MAC) protocol to improve multiple data communication in underwater environment. Aloha protocol is one of the basic and simple protocols, but it has disadvantage such as collision occurs oftenly in communication. If there is collision occured in RF communication, problem can be solved by re-sending the data, but using low frequency in underwater, the re-transmission has difficulties due to slow bit-rate. So, Time Division Multiple Access (TDMA) based MAC protocol is going to be used to avoid collisions, but if there is no data to send in existing TDMA, time slot should not be used. Therefore, this paper proposes dynamic TDMA protocol mechanism with reducing the time slots by sending short "I Have No Data" (IHND) message, if there is no data to transmit. Also, this paper presents mathematic analysis model in relation to data throughput, channel efficiency and verifies performance superiority by comparing the existing TDMA protocols.