• International Journal of Reliability and Applications
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• v.4 no.4
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• pp.191-199
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• 2003

In the present work, a moment inequality is derived for new renewal better (worse) than used in expectation(NRBUE) (NRWUE) distributions. This inequality demonstrates that if the mean life is finite then all higher order moments exist. A new test statistics for testing exponentiality against NRBUE (NRWUE) is introduced based on this inequality. It is shown that the proposed test is simple and has high relative efficiency for some commonly used alternatives. Critical values are tabulated for sample sizes n = 5(1)30. A set of real data is used as an example to elucidate the use of the proposed test statistics for practical reliability analysis.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.102-102
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• 2003

• Journal of the Korea Institute of Information Security & Cryptology
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• v.10 no.3
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• pp.69-76
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• 2000

In this paper we propose a new group key renewal scheme suitable for secure mobile communications in which all members of the group can re-share the new group common key excepted a revoked member using a key distribution center(a trusted center). A renewal group key in the proposed scheme can be shared many times using pre-distributed data by a smart card without a preparation stage. This scheme is also avaliable for a large group network because the transmitted data amount after identifying the revoked member does not depend on a size of group. The secuirty of this scheme is based on the difficulty of the discrete logarithm problem.

• International Journal of Stem Cells
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• v.16 no.1
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• pp.44-51
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• 2023

Background and Objectives: DNA methyltransferases (Dnmts) play an important role in regulating DNA methylation during early developmental processes and cellular differentiation. In this study, we aimed to investigate the role of Dnmts in neural differentiation of embryonic stem cells (ESCs) and in maintenance of the resulting neural stem cells (NSCs). Methods and Results: We used three types of Dnmt knockout (KO) ESCs, including Dnmt1 KO, Dnmt3a/3b double KO (Dnmt3 DKO), and Dnmt1/3a/3b triple KO (Dnmt TKO), to investigate the role of Dnmts in neural differentiation of ESCs. All three types of Dnmt KO ESCs could form neural rosette and differentiate into NSCs in vitro. Interestingly, however, after passage three, Dnmt KO ESC-derived NSCs could not maintain their self-renewal and differentiated into neurons and glial cells. Conclusions: Taken together, the data suggested that, although deficiency of Dnmts had no effect on the differentiation of ESCs into NSCs, the latter had defective maintenance, thereby indicating that Dnmts are crucial for self-renewal of NSCs.

• The Korean Journal of Franchise Management
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• v.15 no.3
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• pp.1-15
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• 2024

Purpose: The insurance market is steadily growing, with General Agencies (GA) experiencing rapid sales increases. GAs need marketing strategies to boost contract renewal intentions by effectively managing customer relationships. This study examines the impact of perceived customer orientation and sales orientation on customer trust, identification, and renewal intentions with GA insurance planners. Research design, data, and methodology: The study surveyed customers who subscribe to insurance products from GA-affiliated insurance planners. Out of 615 respondents, 251 valid responses were analyzed using frequency analysis, measurement models, and structural equation modeling (SEM) with SmartPLS 4.0. Result: The study revealed that customer orientation positively affects cognitive trust and sense of identification. In contrast, sales orientation did not significantly impact customer trust or identification. Additionally, customer trust positively influences sense of identification, and both trust and identification positively affect the intention to renew the contract. Conclusions: Implementing a customer-oriented marketing strategy is essential for providing tailored customer management services and maintaining or improving the quality of customer relationships for insurance planners. Given that insurance products require long-term management, it is crucial for planners to build trust, enhance customer identification, and offer continuous customer management to meet customers' needs effectively.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.3
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• pp.129-141
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• 2005

It is difficult to edit large-scale digital maps because of problems of cost and process and it is carried out by aerial photogrammetry in renewal periods. Five years of update period cannot provide exact data required in the fast-moving age. This study is to analyze applicability and impact for editing digital map of road system using the GPS-Van. Results are compared with accuracy of the data acquisition with GPS-Van positioning. INS data are affected by the barrier to receive GPS data. But high accuracy were achieved by thorough plans according to work order. By using GPS Van and fieldwork at the same time for editing and renewal of digital map, it is expected that this method can be used to reduce costs in the economic and temporal aspects, and provide rapid and accurate digital map of road system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6376-6384
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• 2015

In practice of urban redevelopment promotion projects, since the decision-making is dependent on the verbal agreements between the participants, planning changes are frequently occur. A master plan can be utilized as an effective feedback and adjusting means for decisions. It is a difficult to establish a master plan quickly and effectively to consider the large number of information. Effective decision support system that can storage and retrieval information items systematically and efficiently necessary when planning master plan is required. In this study, a data-warehouse prototype that supports the master planning at early stage was suggested. A metadata index database was developed by identifying information items of base survey results and master plan cases. Also user interface for information searching was presented. The applicability of the prototype was evaluated by case application. It was found that the prototype allows effective searching of desired information through meta data.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.183-192
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• 2008

The Purpose of this study is to find the land use condition and housing development of hillside areas in Busan metropolitan city. For this purpose, data of land use in more than meters above the sea level 80m are collected and analysed. The results of this study provide that 44.22% of the area of Busan hold more than meters above the sea level 80m and many aged buildings occupy the hillside areas. Moreover 30.13% of the redevelopment zone in housing redevelopment hold more than meters above the sea level 80m. In consequence, buildings of hillside areas should be maintained and it is necessary to make topographical adaptation plan. Based on these findings this study suggests that introduce the Conjoint Renewal Program.

• Ocean Science Journal
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• v.43 no.1
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• pp.39-48
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• 2008

Tritium ($^3H$ or T) has been produced mostly by atmospheric nuclear weapon tests, and entered the ocean in the form of water (HTO). As tritium exists as water itself, it has been regarded as an ideal tool to study the transport of water masses. In April 2001 we collected water samples in the western Japan Basin (WJB) for tritium and helium measurement. The timely sampling provided direct evidence of the bottom water formation, resulting in the drastic increase in tritium concentration from 0.3 TU in 2000 to 0.67 TU in 2001. Considering that the new bottom waters were found mostly in the WJB, it implies that maximum 1% of the whole bottom layer below 2600 m should be replaced with the surface water during the severely cold winter 2000 2001. $^3H-^3He$ age, showing the elapsed time since the water left from the surface, can be used to calculate oxygen utilization rate by dividing AOU by the age. Under the condition of 90% oxygen saturation in the surface water, the integration of OUR in the water column below 200 m yields net oxygen consumption of 12 mol $(O_2)m^{-2}yr^{-1}$, which corresponds to the export production of $99\;g\;C\;m^{-2}yr^{-1}$. This estimate is comparable to a previous estimate based on satellite data and implies that the ratio of export to primary production(f-ratio) is as high as 0.5 in the WJB.

• Journal of Korean Society of Rural Planning
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• v.9 no.3 s.20
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• pp.9-16
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• 2003

The aim of this study is to analyze the improvement of housing renewal project and suggest the conditions of rural housing environment filled with the resident's desire, requirements concerning about characteristics of a rural environment and temporal and social requirements. The project for improvement of rural housing environment has been executed in a few ways: reform of the rural housing environment and the development of territories for settlement of a desolate region. To analyze and assess the accomplishments, we considered codes and process related to the project for improvement of rural housing environment and analyzed present conditions and problems through many reference books and administrative data. According to these results, devices in future business for improvement of rural housing environment are as follows; It should required a rational allocation of working space, living space, cultural activity space suitable for rural area characteristics and changed into uniformed system in various projects governed by different institutions.