• Journal of KIISE:Software and Applications
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• v.26 no.8
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• pp.974-987
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• 1999

이동 컴퓨팅 환경에서 자주 접근하는 데이터에 대한 캐싱은 무선 채널의 좁은 대역폭에서 경쟁을 줄일 수 있는 유용한 기술이다. 그러나, 트랜잭션 캐시 일관성을 지원하는 전통적인 클라이언트/서버 전략은 클라이언트와 서버간에 많은 양의 통신을 필요로 하기 때문에 이동 클라이언트/서버 컴퓨팅 환경에서는 적절하지 않다. 본 논문에서는 브로드캐스트-기반 캐시 무효화 정책을 사용하면서 트랜잭션 캐시 일관성을 지원하는 OCC-UTS (Optimistic Concurrency Control with Update TimeStamp) 프로토콜을 제안한다. 접근한 데이터에 대한 일관성 검사 및 완료 프로토콜은 캐시 무효화 과정의 내부 과정으로 완전 분산 형태로 효율적으로 구현되며, 일관성 체크의 대부분이 이동 클라이언트에서 수행된다. 또한, 분석 모델에 기반한 성능 비교를 통해, 본 논문에서 제안하는 OCC-UTS 프로토콜이 다른 경쟁 프로토콜보다 높은 트랜잭션 처리율을 얻으며, 데이터 항목을 자주 접근하면 할수록 지역 캐시를 사용하는 OCC-UTS 프로토콜이 더 효율적임을 보인다. 이동 클라이언트의 접속 단절에 대해서는 무효화 브로드캐스트 윈도우를 크게 하여 접속 단절에 적절히 대처할 수 있다.Abstract In a mobile computing environment, caching of frequently accessed data has been shown to be a useful technique for reducing contention on the narrow bandwidth of the wireless channels. However, the traditional client/server strategies for supporting transactional cache consistency that require extensive communications between a client and a server are not appropriate in a mobile client/server computing environment. In this paper, we propose a new protocol, called OCC-UTS (Optimisitic Concurrency Control with Update TimeStamp), to support transactional cache consistency in a mobile client/server computing environment by utilizing the broadcast-based solutions for the problem of invalidating caches. The consistency check on accessed data and the commitment protocol are implemented in a truly distributed fashion as an integral part of cache invalidation process, with most burden of consistency check being downloaded to mobile clients. Also, our experiments based on an analytical model substantiate the basic idea and study the performance characteristics. Experimental results show that OCC-UTS protocol without local cache outperforms other competitor protocol, and the more frequent a mobile client accesses data items the more efficient OCC-UTS protocol with local cache is. With respect to disconnection, the tolerance to disconnection is improved if the invalidation broadcast window size is extended.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.1
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• pp.68-79
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• 2008

Because local cities are different from large cities, they need to reflect their own characteristics of housing market. Thus in order to obtain useful implications for the establishing sound housing market in Jinju City, this paper investigated the characteristics of spatial distribution and determinant factors that affect apartment price in Jinju City. GIS representation of the apartments showed that most of old and small apartments were built in 'land readjustment project' areas executed in 1970s. On the contrary, new and large scale apartment complexes were built quite recently and distributed in the western and southern parts of the city. Next, in order to examine the factors which affect apartment price, this paper subtracted firstly several variables from the related studies. However in order to avoid multi-colinearity, variables were summarized by means of factor analysis. Then, setting apartment price as a dependant variable, 12 hedonic price models were established with 33 independent variables. As results, building age, floor area, accessibility to university and hospital, accessibility to arterial road, and stair-type building were turned out to be significant. These results will be used in making the supply and allocation plan of urban facilities and housing. Finally as conclusions this paper emphasized the need of periodic analysis of local housing market and establishing detailed housing information systems.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.264-279
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• 2015

This study is conducted to investigate the relationships among service quality, satisfaction, and revisit intention of franchise snack bars customers located in Busan. The quality of franchise Korean snack bars' service was estimated by examining three sub-dimensions: service environment factors, interaction factors, and outcome quality factors, which are classified from Brady & Cronin's third-dimensional model. The survey was performed from March 9th to March 13th in 2015. Total 300 questionnaires were distributed and 272 questionnaires were employed for final analysis. SPSS 21.0 program was used to derive the following: factor analysis, reliability analysis, correlation, simple regression and multiple regression analysis. In results, the approachableness such as convenience for access was the most important reason when people choose a franchise Korean snack bar company followed by food taste and reasonable price. In addition, the results indicate that service environment quality, interaction quality, and outcome quality have all positive impact on the customers' satisfaction as well as revisit intention. Specifically, outcome quality have the greatest influence on the satisfaction and revisit intention among three service quality factors. This outcome proves that Korean snack bar franchise companies need to investigate more to improve their outcome quality such as food quality and serving time to satisfy customers. In conclusion, current study confirmed the relationships among service quality, satisfaction, and revisit intention in context of franchise snack bar stores. These results will suggest the snack bar foodservice segmentation as valuable marketing strategic, and that it can be utilized as a fundamental data to establish an efficient business plan in the industry.

• Economic and Environmental Geology
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• v.23 no.2
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• pp.245-259
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• 1990

Petrochemical analyses of granitic rocks including trace element, REE and oxygen isotope were carried out to understand petrogenesis of plutonic rocks from the Chungju, Wolaksan and Jecheon granite batholiths, which might be related with tungsten-base metal-fluorite mineralization in the Hwanggangri metallogenic province. Different geochemical characteristics such as major and trace elements were found between Jurassic Daebo granitic rocks (Chungju, Jecheon, Wonju, and Boeun granitic rocks) and Cretaceous Bulgugsa granitic rocks (Wolaksan, Muamsa and Sokrisan granitic rocks). Cretaceous granitoids are characterized by high $SiO_2$and $K_2O$ contents and low $TiO_2$, $Al_2O_3$, MgO and CaO contents. They also have relatively high contents of trace elements(Zn, V, Co, Cr, Sr, and Ba) in comparison with the Jurassic granitoids. (Eu)/($Eu^*$) and $(La/Lu)_{CN}$ ratios of Jurassic plutons vary from 0.78 to 1.13 and from 26.02 to 30.5, respectively, while the ratios of Cretaceous ones range from 0.22 to 0.28 and from 4.42 to 14.2, respectively. The REE patterns of the Cretaceous and Jurassic granitic rocks have quite different Eu anomalies: large negative Eu anomaly in the former, and mild or absent Eu anomaly in the latter. The large Eu negative of Cretaceous granitic rocks are interpreted as a differentiated product of fractional crystallization of granitic magma deduced by Rayleigh fractionation model(Tsusue et al., 1987). Oxygen isotopic compositions of quartz for Daebo and Bulgugsa granitic rocks range from 9.98 to 10.51‰ and from 8.26 to 9.56‰, respectively. The Daebo granitic rocks enriched in $^{18}0$ suggest that the magma be undergone different partial melting processes from the Bulgugsa ones. Of the Bulgugsa granitoids, Wolaksan and Sokrisan mass have different contents of trace elements and ${\delta}\;^{18}0$ values of the silicate minerals, which indicate that they are not from the identical source of magma. Many mineral deposits are distributed in and/or near the Wolaksan and Muamsa granitic rocks, but a few mineral deposits are found in and near the Chungju and Jecheon granite batholiths. It might be depend on geochemisty of the related igneous rocks which have low contents of Ba, Sr, Co, V, Cr, Ni, Zn and high contents of Nb and Y, and on lithology of country rocks such as cabonate and noncarbonate rocks.

• Economic and Environmental Geology
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• v.48 no.4
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• pp.313-324
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• 2015

This study constructed a 3D geological model for Uggi Nuur Fe-Mn mineralization zone in Mongolia, and the 3D geological distribution is cross-analyzed with magnetic anomaly distribution to figure out relationship between ore zone and subsurface geology. As a result of 4 step 3D modeling procedures including geological cross section, surface modeling, foliation modeling and solid modeling, the geology of the both study area is bordered by faults in NW direction with Munguntessj formation being located in the west side of the fault while Yashill formation is located on the other side of the fault. Moreover, the strike direction of foliation in the both formation shows same directional pattern with the NW faults. The magnetic anomaly distribution reveals that higher anomaly values are concentrated to near the ground surface. The analyses of 3 dimensional distribution between subsurface geology and magnetic anomaly indicates that higher anomaly is mainly distributed over the Munguntessj formation as a elongated lens bodies whereas the magnetic anomaly is evenly found in the both of Munguntessj formation and Yashill formation in the study area 2. It infers that volcanic activities associated mineralization occurred during silurian period, and the mineralized zone is thought to be realigned along the geological structures caused by later stage tectonic activities.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.76-91
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• 2016

The purpose of this study is to analyze the effects of spatial characteristics, such as land cover and topography, on heat wave days from the city of Milyang, which has recently drawn attention for its heat wave problems. The number of heat wave days was calculated utilizing RCP-based South Korea climate data from 2000 to 2010. Land cover types were reclassified into urban area, agricultural area, forest area, water, and grassland using 2000, 2005, and 2010 land cover data constructed by the Ministry of Environment. Topographical features were analyzed by topographic position index (TPI) using a digital elevation model (DEM) with 30 m spatial resolution. The results show that the number of heat wave days was 31.4 days in 2000, which was the highest, followed by 26.9 days in 2008, 24.2 days in 2001, and 24.0 days in 2010. The heat wave distribution was relatively higher in agricultural areas, valleys, and rural areas. The topography of Milyang contains more mountainous slope (51.6%) than flat (19.7%), while large-scale valleys (12.2%) are distributed across some of the western region. Correlation analysis between heat wave and spatial characteristics showed that the correlation between forest area land cover and number of heat wave days was negative (-0.109), indicating that heat wave can be mitigated. Topographically, flat areas and heat wave showed a positive correlation (0.305). These results provide important insights for urban planning and environmental management for understanding the impact of land development and topographic change on heat wave.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.99-109
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• 2012

The purpose of this study was to scrutinize and compare the perceptions of Global and Korean HRD Professionals in Workplace Learning and Performance(WLP) competencies in Korea. To answer these questions, the following research methods were employed. A questionnaire, which was modified and translates from the 2004 ASTD model for WLP, was distributed to 319 HRD consultants working in Seoul and Kyounggi-Do. It was sent out directly and by email. Among returned questionnaires, 205 were valid to be examined. The important findings of the study were as follows. First, the role of business partner ranked highest in the level of importance of WLP roles in Korean and the role of special professional ranked highest in global. For the competencies of WLP, effective communication ranked highest both Korean and global. Based on the findings of this study, the conclusion was as follows. First, the perceptions of WLP roles were different between Korean and global HRD professionals. The reason why it's differences is because the size of market are different. Second, the perceptions of WLP competencies were similar between Korean and global HRD professionals. HRD professionals should need to professionalize the communication skills continuously.

• The Journal of Society for e-Business Studies
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• v.15 no.2
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• pp.137-166
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• 2010

A virtual team is defined a group of people that use electronic communications for some or all of their interactions with other team members. Because team members of a virtual team are physically and temporally distributed, a team's transactive memory system(TMS) is considered to be crucial for the team's effectiveness and performance. TMS refers to a set of individual memory systems which integrate knowledge possessed by particular members through a shared awareness of who knows what. This paper seeks to understand (1) how a virtual team's TMS influences team performance, and (2) what factors contribute to developing the team's TMS. Given these purposes, through the extensive literature review, we first identified components and antecedents to develop a theoretical model that predicts a virtual team's performance. Using the survey data gathered from 172 virtual teams, this study found that expertise location, coordination, and cognition-based trust which were proposed as three components of TMS positively influenced a virtual team's performance. Furthermore, this study uncovered that perceived media richness, network tie strength, and shared norms significantly influenced the components of TMS, while geographical dispersion did not exert any significant influence on TMS.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.427-440
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• 2020

This study is a study on the cooking department where chefs who belong to the desired job of elementary and middle school students work together with the recognition increase through the media. The cooking department, which has a vertical structure at work, can be said to have an absolute influence of the chef. However, the cooking department needs to change according to the times. The purpose of this study was to examine how chef's shared leadership affects the chef's emotional commitment, continuous commitment, job satisfaction, and job performance. Therefore, a questionnaire was distributed to the employees currently working in the cooking department of a five-star hotel in Seoul, and a sample of 319 copies was prepared. In statistical analysis, the items were refined through exploratory factor analysis, confirmatory factor analysis, reliability analysis, and correlation analysis, and the hypotheses were verified through structural model analysis.As a result, Chef's shared leadership influences the emotional commitment of cooks, job satisfaction and job performance. In particular, emotional commitment and continuous commitment did not affect cooks' job satisfaction and job performance. In conclusion, to improve the performance of the organization, the hotel culinary department must establish a culture of sharing and communication. This suggests that establishing goals and visions will lead to job satisfaction and performance not only for individual cooks but also for the entire department. Therefore, it is expected to contribute to the efficient human resource management for the cooks in the hotel cooking department.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.5
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• pp.101-111
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• 2017

This Research is to Find how the CSR Activities for the Growth of Stable and Sustainable Family Business do Influence the Improvement of Company's Brand Image and Service Purchase Intention. It is Aimed for Finding how the Image of Company Pursuing the Diverse CSR Activities is Recognized by General Consumers and the Correlation between the Improvement of Company's Image and the Product & Service Purchase Intention. 323 Exemplars were Distributed to the University Students in Seoul Metropolitan and Chungcheong Area, and 314 Finally were Used for the Analysis. It was Investigated the Demographical Factors, the Important Fields among Company's CSR Activities, the Reason for Company's CSR Activities, the Preferred Companies among Sponsoring Companies. It was Analyzed Three Items of Company Image such as Product/Service, Potential Competence, Relation to Public Benefit and the Regression Model was Investigated how these Three Items do Influence the Purchase Intention. The Research Results Show 'the Improvement of Social Awareness for Company' and 'Negative Awareness Change for Company' as the Reason for CSR. Consumers have the Preference to the Companies Actively Sponsoring Culture & Arts, and this Generally Affects the Business Results, and thus, it is Considered that the Companies have to Contribute the Local Society with the Sprit of Corporate Citizenship in Accordance with the Consumers needs, and Actively to Extend the Culture & Arts Sponsorship.