• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.6
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• pp.111-116
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• 2009

LEACH is a important hierarchical protocol in wireless sensor network. In LEACH, the head is randomly selected for balanced energy consume. In LEACH-C, the node that has more energy than the average value is selected for the network life cycle. However, the round continues, the improved protocol is needed because the energy and network are changed. In this paper, LEACH, LEACH-C is not considered the energy consumed in the round because of wasted energy and reduce the time for presenting a new round time was set. And proposed the new algorithm using the energy threshold for the cluster head selection and the round time. In simulation, we show the improved performance compared to existing protocols.

• Korean Journal of Social Welfare Studies
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• v.42 no.1
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• pp.305-331
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• 2011

This study analyzes the consumption patterns of the poor households. The first objective of this analysis is to show that the group living in poverty get not one consumption pattern but several types of consumption patterns. The second objective is to understand what factors effect the consumption patterns. This study use the data of Korea Welfare Panel Study in 2008 & 2009. In oder to achieve first goal, We conduct factor analysis and cluster analysis. And to achieve second goal, We conduct multinomial logistic Analysis. Major findings are as follows. First we find six patterns of consuming types of the poor households. They are education oriented consuming type, diet oriented type, social network oriented type, transportation-communication oriented type, health & medical oriented type, and housing expenditure oriented type. Second we find these consumption patterns are effected by not economic factors but socio-populational factors, especially by life cycle of members of household.

• Korean Journal of Human Ecology
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• v.2 no.1
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• pp.52-67
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• 1999

The primary purpose of this study was to analyze the types of home managers in association with effects of resourcefulness, communication and the conditions for effective home management＇ proposed by Shape and Winter(1991). A survey was conducted by subjects of 300 wives in Kwangju city. The statistical data were obtained by cluster analysis, one-way ANOVA, Duncan＇s test and chi-square test. Manager types based on the four conditions, resourcefulness and communication were classified into four clusters. Educational background, job status, family types, family life cycle and age difference between the oldest and the youngest child of the subjects were different from manager types. In conclusion, this study identified the four conditions of performance-condition dichotomy, timing, high level and middle range, resourcefulness, and communications in order to develop managerial capability. (Korean J Human Ecology 2(1) : 52∼67, 1999)

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.507-511
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• 2008

Supporting energy efficiency and load balancing in wireless sensor network is the most important issue in devising the hierarchical routing protocols. Recently, the dual layered clustering scheme with GPS was proposed for the supporting of load balancing for cluster heads but there would be many collided messages in the overlapped area between two layers. Thereby, the purpose of this paper is to reduce the collision rate in the overlapped layer by concisely distinguish them with the same number of nodes in them. For the layer partition, this paper uses an equation $x^2+ y^2{\le}(\frac{R}{\sqrt{2\pi}})^2$ to distinguish layers. By using it, the scheme could efficiently distinguish two layers and gets the balanced number of elements in them. Therefore, the proposed routing scheme could prolong the overall network life cycle about 10% compared to the previous two layered clustering scheme.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.116-128
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• 2022

Purpose: The paper aims to: 1) identify the reasons for the low usage of recycled paper in domestic workplaces and the premature state of recycled paper industry; 2) assess the environmental effects of replacing domestically consumed copy papers with recycled papers; and 3) suggest ways in which the recycled paper industry can expand in South Korea. Method: Questionnaire survey with cluster sampling is used to identify the attitudes and behavior with respect to recycled copy paper, the results of which are analyzed using SPSS. The environmental effect of replacing copy papers with recycled paper is assessed through the Life Cycle Assessment approach and Paper Calculator V4.0. Result: While the respondent's experience in using recycled copy paper was relatively low, they tend to acknowledge the need for its use and show relatively high satisfaction with the quality of the recycled paper. The environmental benefits of replacing ordinary copy paper with 40%+ recycled paper under the 10% market share increase scenario amounts to 60,000 tons of CO₂ emissions reductions. Conclusion: The results from the attitude survey and market research, five approaches to improving the recycled copy paper market are suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3472-3480
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• 2010

The Clustering technology of Energy efficiency wireless sensor network gets the energy efficiency by reducing the number of communication between sensor nodes and sink node. In this paper, First analyzed on the clustering technique of the distributed clustering protocol routing scheme LEACH (Low Energy Adaptive Clustering Hierarchy) and HEED (Hybrid, Energy-Efficient Distributed Clustering Approach), and based on this, new energy-efficient clustering technique is proposed for the cause the maximum delay of dead nodes and to increase the lifetime of the network. In the proposed method, the cluster head is elect the optimal efficiency node based on the residual energy information of each member node and located information between sink node and cluster node, and elected a node in the cluster head since the data transfer process from the data been sent to the sink node to form a network by sending the energy consumption of individual nodes evenly to increase the network's entire life is the purpose of this study. To verify the performance of the proposed method through simulation and compared with existing clustering techniques. As a result, compared to the existing method of the network life cycle is approximately 5-10% improvement could be confirmed.

• Information Systems Review
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• v.10 no.2
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• pp.195-209
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• 2008

Customers' needs change every moment. Profitability of stores can't be increased anymore with an existing standardized chain store management. Accordingly, a personalized store management tool needs through prediction of customers' preference. In this study, we propose a recommending procedure using dynamic customers' preference by analyzing the transaction database. We utilize self-organizing map algorithm and association rule mining which are applied to cluster the chain stores and explore purchase sequence of customers. We demonstrate that the proposed methodology makes an effect on recommendation of products in the market which is characterized by a fast fashion and a short product life cycle.

• The Journal of Fisheries Business Administration
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• v.46 no.3
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• pp.103-118
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• 2015

The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.7
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• pp.1137-1148
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• 2008

The purposes of this study were to investigate the differences in clothing consumption behaviors among female consumer groups in their twenties and to understand the type of consumer group pursuing fast fashion. Questionnaire survey was conducted to 230 female consumers residing in Seoul and Kyung Gi area from June 18 to 29 in 2007, and 178 were used for data analysis. Data analysis were conducted with SPSS 12 program on the reliability test, factor analysis, cluster analysis, correlation analysis, ANOVA, Duncan's multiple range test. Factors analyses were employed for the attitude toward fashion and shopping, and shopping motives. Four factors were formulated for the attitude toward fashion: interest in fashion, fashion-orientation, fashion leadership and fashion conformity. Six factors for the attitude toward shopping were found: information searching, shopping enjoyment, store patronage, impulse buying, brand-orientation and convenience. Buying motives for fashion goods were classified into 3 factors: for matching & occasion, to-be-in-fashion and for necessity. Four clusters were identified based on the attitude toward fashion: the fashion-interested, the fashion-indifferent, fashion leaders and the individuality-oriented. Among the groups, significant differences were found in information searching, shopping enjoyment and store patronage. Fashion leaders tended to spend more for expensive and up-to-dated fashion items, and for higher quantity than other groups. Consequently fashion leaders showed attractive customer characteristics for the fast fashion companies.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.8-16
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• 2013

A GAL4 type transcription factor gene (formally annotated as AN3912) locating downstream of sndA (AN3911) was characterized. The putative transcription factor carries both Zn(II)2Cys6 binuclear cluster DNA-binding domain and transcription activator domain. The gene named gtfA (gal4 type transcription factor) had an open reading frame which consisted of 762 amino acids and was disrupted by three introns. The deletion mutant produced reduced amount of conidia but increased amount of fruiting bodies, suggesting that the GtfA make function in decision of asexual preferential to sexual development. The forced over expression of gtfA caused the retardation of fruiting body formation on high glucose concentration. The transcript level of gtfA was kept constant through the life cycle except late vegetative stage and early sexual development stage during which slight increase was found. The expression of gtfA was not significantly affected by sexual or asexual development regulators, such as VeA, NsdD or FluG, FadA, and SfaD. The GtfA repressed the nsdC transcription, which suggested that GftA control sexual development negatively via negative regulation of nsdC expression.