• Journal of KIISE:Information Networking
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• v.35 no.1
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• pp.21-33
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• 2008

The wireless sensor nodes near to the fixed sink node suffer from the quickly exhausted battery energy. To address this problem, the mobile sink node has been applied to distribute the energy consumption into all wireless sensor nodes. However, since the mobile sink node moves, the data collection scheduling scheme is necessary for the sink node to receive the data from all sensor nodes as fair as possible. The application fields of wireless sensor network need the real-time processing. If the uneven data collection occurs in the wireless sensor network, the real-time processing for the urgent events can not be satisfied. In this paper, a new method is proposed to support the lair data collection between all sensor nodes. The proposed method performs the scheduling algorithm based on the resident time of the sink node staying in a radius of communication range and the amount of data transferred already. In this paper, the proposed method and existing data collection scheduling schemes are evaluated in wireless sensor network with the mobile sink node. The result shows that the proposed method provides the best fairness among all data collection schemes.

• Journal of KIISE:Information Networking
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• v.37 no.3
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• pp.175-186
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• 2010

Due to the emergence of new application programs and the fast growth of Internet users, Internet routers are required to provide the quality of services according to the class of input packets, which is identified by wire-speed packet classification. For a pre-defined rule set, by performing multi-dimensional search using various header fields of an input packet, packet classification determines the highest priority rule matching to the input packet. Efficient packet classification algorithms have been widely studied. Tuple pruning algorithm provides fast classification performance using hash-based search against the candidate tuples that may include matching rules. Bloom filter is an efficient data structure composed of a bit vector which represents the membership information of each element included in a given set. It is used as a pre-filter determining whether a specific input is a member of a set or not. This paper proposes new tuple pruning algorithms using Bloom filters, which effectively remove unnecessary tuples which do not include matching rules. Using the database known to be similar to actual rule sets used in Internet routers, simulation results show that the proposed tuple pruning algorithm provides faster packet classification as well as consumes smaller memory amount compared with the previous tuple pruning algorithm.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.12-22
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• 2000

This paper presents the window-based permit distribution scheme for efficient medium access control to support multiclass traffic in APON(ATM over passive optical network). The proposed MAC protocol considers the characteristics of QoS(Quality of Service) for various traffic classes. A periodic RAU(request access unit) in upstream direction, includes dedicative request fields for each traffic category within the request slot. The transmission of upstream cell is permitted by the proposed window-based spacing scheme which distributes the requested traffic into several segments in the unit of one spacing window. The delay sensitive traffic source such as CBR or VBR with the stringent requirements on CDV and delay, is allocated prior to any other class. In order to reduce the CDV, so that the permit arrival rate close to the cell arrival rate, Running-Window algorithm is applied to permit distribution processing for these classes. The ABR traffic, which has not-strict CDV or delay criteria, is allocated flexibly to the residual bandwidth in FIFO manner. UBR traffic is allocated with the lowest priority for the remaining capacity. The performance of proposed protocol is evaluated in terms of transfer delay and 1-point CDV according to various offered load. The simulation results show that our protocol has the prominent improvement on CDV and delay performance with compared to the previous protocol.

• Korean Journal of Environment and Ecology
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• v.26 no.2
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• pp.233-246
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• 2012

We need to analyze the ecological characteristics in the basin of agricultural reservoir that include urbanized area, agricultural area and fringe area, etc. The purpose of this study is not only that presenting the methods of basin ecosystem management but also suggesting ecosystem management plan proposals for the water quality based on analysis of ecological characteristics. As the results of analysis, the urbanized area(the ratio of area(ROA): 14.0%) is most likely to possibility of water pollution, then followed by paddy fields(ROA: 65.5%) where a wide spread up-basin(or up-stream), farmlands(ROA: 11.3%), farm buildings(ROA: 5.7%) and orchard(ROA: 3.9%). According to those, we investigated the impact degree of water pollutants. Thus, we were able to classify 5 types through considering the biotope assessment and the hydrosphere basin assessment, i.e. the level of priority control for source pollution. As a result, the source pollution intensive management area(11.3%) where are adjacent waterfront has caused water pollution, however, most importantly, it is necessary to control in source pollution management area(0.6%) that are away from waterfront. In conclusion, according to the these results, the plan of basin ecosystem management for the water quality should be included the plan of ecosystem conservation and restoration such as improving inhabitants function, controling environmentally sound basin management, promoting biodiversity.

• Journal of the Korean Society for Library and Information Science
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• v.30 no.2
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• pp.149-165
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• 1996

Hong-sii Tokso-rok (홍씨독서록 or Hong's Annotated Bibliography of Korean and Chinise Book) is the only work on the history of Korean bibliographies that has the introductory notes to each class, that is description of the origin of subject fields, transition, and characteristics at the beginning of each class. This paper is aimed to examine the outline of the introductory description of class, to analyze the Four Category Classification System(사부분류법) devised by Hong Sok-chu, and to explain how the classes of Four Category Classification are set and ordered. This paper shows several characteristics in the idea of Hong's classification system. There characteristics were discovered by analyzing the content of each introduction of classes. The characteristics ale as follows First, classes are organize and arranged from the substantial problem to nonsubstantial ones. In other words, the greater the distance of the class from the substantial problem of Confucianism, the farther the order of the class will be found from the substantial problem. The order of classes is set by how the class is closed to the substantial problem in the same hierarchy. This principle is strictly applied to the Hong's classification system. Second, on the basis of democratic thought, he del·eloped the classification system. In other words, when he set up the priority of classes, he put emphasis on the democratism as a guideline. The organization of classes belong to the catagories of history (Sa-bu, 사부) and philosophy(Cha-bu, 자부) showed the application of this principle. Conclusively, this paper found that Hong did not randomly arrange the class older, but he set the class order with objective reasons and logic when he set the class order of arrangement.

• The Journal of Society for e-Business Studies
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• v.18 no.2
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• pp.205-222
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• 2013

One of the recent important issues in IT fields is the convergence. It had been simply focused on functional convergence of technologyies. However the convergence in terms of businesses or services also has been made in recent years. The convergence between broadcasting and telecommunication industries can be possible because the e-transformation of broadcasting industry based on digital technology such as multimedia and multi-channel, can be combined with the high speed telecommunication network. It is giving a birth of various convergence services such as IPTV. IPTV is a kind of new service that is combined with the convergence of network, contents, and device. Nevertheless the controversy about the scope and the value of this new convergence service has constantly been raised; for example, what is the difference between IPTV and Internet TV? or what are the benefits that customers can have? This study measured the expectation level and the cognitive level of users before and after using the service and analyzed the gap between the importance and the satisfaction of the service. From this study, we proposed the priority of each function by analysing Importance-Performance Analysis(IPA) method to suggest required functions of IPTV service based on N-Screen technology. This study will identify the gap of awareness level between service providers and end users for the functions of broadcasting and telecommunications convergence service and suggest a solution enhancing user satisfaction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.56-64
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• 2020

Service quality research is being conducted actively to improve customer satisfaction in various fields, but no research has been done on the service quality of small arms in the national defense. To enhance the user satisfaction and quality of small arms, this study aimed to derive the main quality attributes, measure the current level of satisfaction, and explore the elements requiring improvement. For this, a questionnaire survey based on the Kano model and SERVQUAL model was conducted on the identified service quality factors through discussions of experts involved in the production, quality assurance, and operation. All service quality factors were classified as one-dimensional elements, and an analysis of the Kano-SERVQUAL integrated approach showed that the user's expectation and dissatisfaction coefficient had a strong positive correlation with a 1% significance level, and user's perception value and satisfaction coefficient had a negative correlation with the 1% significance level. Using the Kano-SERVQUAL integrated approach, the priority service quality attributes for small arms requiring improvement among the many areas of service quality could be identified. Overall, it is expected that service-quality-level measurements can be used to improve the quality level of munitions as well as user satisfaction.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.373-378
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• 2001

In order to analyze the problems and improvement methods in the quality management of domestic apartment construction projects, this study derived the four barrier factors through relevant literature survey and interviews with construction practitioners. Among these four factors, which are 1) policies and regulations, 2) technologies, 3) human and organization, and 4) other miscellaneous aspects, the human and organization factor is the main focus of this survey and it was decomposed into perception, management system, education, and system on quality management according to the Taguchi's S/N theory to survey existing problems and suggest improvement methods for them. The survey on the quality perception showed that all the members need to cooperate actively, and CEO and chief construction managers should recognize the quality as the highest priority and act by themselves accordingly. The survey on the quality management showed that they need to reform their business process to reduce redundant tasks and miscommunications among participants. Quality education should be provided in a way that people at different management level can be educated differently with close relation to their practices. Quality systems should help corrective actions against quality problems at construction fields. Also with clear quality management implantation polices and objectives, the quality system should be established in order to support better communication among project stakeholders.

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.34-39
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• 2010

The purpose of this study is to suggest objective evaluation model as a plan to utilize as opportunity in establishing judgment standard of mutual inspection criteria and to upgrade inspection ability by reviewing and analyzing level of danger and importance in advance based on inspection results of inspection institutions regarding tower cranes used in construction fields. Tower crane is a mechanical device transporting construction supplies and heavy materials to places over 20~150M high from the ground for the period ranging from a short time of 2~3 months to two years after being installed in construction sites in vicinity of buildings or structures and is an important facility indispensable for construction sites. However, since use period after installation is short and professional technical ability of technicians working on-site about of tower crane is poor, systematic and quantitative safety management is not carried out As a part of researches on procedure of RBI(Risk Based Inspection) possible to apply to Knowledge Based System based on knowledge and experiences of experts as well as to tower cranes for solving these problems, quantitative RPN(Risk Priority Number) was applied to RPN utilizing technique of FMEA(Failure Mode and Effect Analyses). When general RBI 80/20 Rule was applied parts with high level of risks were found out as wire rope, hoist up/down safety device, reduction gear, and etc. However, since there are still many insufficient parts as risk analyses of tower crane were not established, it is necessary for experts with sufficient experiences and knowledge to supplement active RBI techniques and continuous researches on tower cranes by sharing and setting up data base of important information with this study as a starting point.

• Korean Journal of Construction Engineering and Management
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• v.18 no.1
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• pp.58-64
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• 2017

Construction Management (CM) is being utilized as an efficient project management system. Construction management system provide scientific management techniques as well as the expert's service with the expertise. Accordingly, CM services demand is continuously increasing in construction project. Construction Management engineer grade is distinguished by the Index of Construction Engineer's Competency (ICEC). Construction management engineer requires a higher score than the other fields. However, junior grade CM engineer can get grade according to the education and qualification. This study was conducted junior grade CM engineer depth interview after analyzing the problem of the current CM engineer grade system. As a result, this study was to extracted the 23 kind competence factors. And, competence factors were five area grouped using affinity diagram method. Next, we analyzed the importance utilizing the Analytic Network Process (ANP) technique. As a result, high priority areas were analyzed to be quality and cost areas associated with project management.