• Journal of KIISE:Computer Systems and Theory
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• v.26 no.9
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• pp.1166-1176
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• 1999

연속 매체, 특히 비디오 데이타에 대한 일반 사용자 연산에는 재생뿐만 아니라 임의 속도 탐색 연산, 정지 연산, 그리고 그 외 다양한 연산이 있다. 이 연산 중에서 원하는 화면을 빨리 찾는 데에 유용한 고속 전진(FF: fast-forward)과 고속 후진(FB: fast-backward)은 재생 연산과는 달리 비순차적인 디스크 접근을 요구한다. 이러한 경우에 디스크 부하가 균등하지 않으면 일부 디스크에 접근이 편중되어 서비스 품질이 떨어진다. 본 논문에서는 디스크 배열을 이용한 저장 시스템에서 디스크 접근을 고르게 분산시키기 위하여 '소수 라운드 로빈(PRR: Prime Round Robin)' 방식으로 연속 매체를 디스크에 배치하는 기법에서 문제가 됐던 낭비된 디스크 저장 공간을 신뢰도 향상을 위해서 사용하는 '그룹화된 패리티를 갖는 소수 라운드 로빈(PRRgp: PRR with Grouped Parities)' 방식을 제안한다. 이 기법은 PRR 기법처럼 임의 속도 검색 연산에 있어서 디스크 배열을 구성하는 모든 디스크의 부하를 균등하게 할뿐만 아니라 낭비됐던 디스크 저장 공간에 신뢰도를 높이기 위한 패리티 정보를 저장함으로서 신뢰도를 향상시킬 수 있다. 신뢰도 모델링 방법으로 조합 모델과 마르코프 모델을 이용해서 결함발생율과 결함복구율을 고려한 신뢰도를 산출하고 비교.분석한다. PRR 기법으로 연속 매체를 저장하고 낭비되는 공간에 패리티 정보를 저장할 경우에 동시에 두 개 이상의 결함 발생 시에 그 결함으로부터 복구가 불가능하지만 PRRgp 기법에서는 약 30% 이상의경우에 대해서 동시에 두 개의 결함 발생 시에 저장한 패리티 정보를 이용한 복구가 가능할 뿐만 아니라 패리티 그룹의 수가 두 개 이상인 경우에는 두 개 이상의 결함에 대해서도 복구가 가능하다.Abstract End-user operations on continuous media (say video data) consist of arbitrary-rate search, pause, and others as well as normal-rate play. FF(fast-forward) / FB(fast-backward) among those operations are desirable to find out the scene of interest but they require non-sequential access of disks. When accesses are clustered to several disks without considering load balance, high quality services in playback may not be available. In this paper, we propose a new disk placement scheme, called PRRgp(Prime Round Robin with Grouped Parities), with enhanced reliability by using the wasted disk storage space in an old one(PRR: Prime Round Robin), in which continuous media are placed on a disk array based storage systems to distribute disk accesses uniformly. The PRRgp can not only achieve load balance of disks consisting of a disk array under arbitrary-rate search like PRR, but also improve reliability by storing parity information on the wasted disk space appropriately. We use combinatorial and Markov models to evaluate the reliability for a disk array and to analyze the results. When continuous media like PRR are placed and parity information on the wasted disk space is stored, we cannot tolerate more than two simultaneous faults. But they can be recovered by using stored parity information for about 30 percent as a whole in case of PRRgp presented in this paper. In addition, more than two faults can be tolerated in case there are more than two parity groups.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8A
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• pp.648-660
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• 2012

The low-power, low-cost femtocell network has been proposed not only to alleviate traffic load to the macro base station (eNB) but also to cover the indoor coverage hole problem. However, in the dense femtocell environment where many femtocells are deployed to cover the whole large office building, performance of such femtocell environment can be deteriorated due to severe co-channel interference problem between the eNB and femtocells and among neighboring femtocells. In particular, a macro UE(mUE) located within femtocell coverage may experience severe co-channel interference from surrounding femtocells. Therefore, In this paper, we propose a novel power control schemes to mitigate interference to a mUE under such dense LTE femtocell environment. With proposed femtocell power control schemes, performance of the mUE can be greatly improved in terms of the outage probability and the SINR while maintaining satisfying femtocell performance. Simulation based performance study shows that the proposed power control scheme is able to enhance mUE performance more than 30% than the conventional dense femtocell in terms of the two performance metrics.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.1
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• pp.135-143
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• 2010

The national base map has its value sand roles as the basic spatial information of the nation. The current national base map that is a 1/5,000 digital map, however, has failed to perform its roles as basic spatial information due to the limitations with its quality and accuracy and requires measures to complement them. Thus this study set out to suggest ways to advance the current 1/5,000 national base map, selected topography and natural features of a digital map that could be made with GSD 0.25m digital aerial photographs, and set up the optimal ways to make a digital map by conducting an experiment of making an optimal digital map with such photographs. It also analyzed the map made with GSD 0.25m digital aerial photographs for accuracy and usability. In order to establish a set of criteria of making a digital map with GSD 0.25m digital aerial photographs, the investigator carried out analyses and picked topography and natural features items, which include 9 large categories, 31 medium categories, and 509 small categories. Then an experiment of making a digital map was conducted according to the digital map making method. As a result, solid drawing was selected as the optimal way to making a digital map, and the optimal process was established. Using the research achievements, a model digital map was made with GSD 0.25mm digital aerial photographs. The map recorded about two times horizontal and vertical location accuracy than the old 1/5,000 digital map and was capable of detailed descriptions of topography and natural features. A new national base map made with GSD 0.25m digital aerial photographs will provide reliable spatial data, thus increasing the level of satisfaction among people and the level of advancement of national base maps.

• Journal of Distribution Science
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• v.13 no.6
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• pp.87-96
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• 2015

Purpose - Several domestic telecommunication companies have made a considerable effort to continuously grow and survive, and they have strived to thrive in the midst of mature market competition. To overcome this challenging situation and to grow continuously, while still meeting customer needs that are becoming more diverse and complicated with the passage of time, extensive support for internal marketing is essential. Without such internal support, companies face serious limitations and market roadblocks. The communication industry is a high-level service industry and a basic communications industry characteristic is its significant dependence on the employees delivering the services. Therefore, entrepreneurs in the information/communications industry, as well as existing competitors, should look to satisfy external customers through critical investment in internal customers (employees). Therefore, it is important for research to examine how internal factors influence technology innovation and service quality, which are the key drivers for companies that are seeking leading market positions. Research design, data, and methodology - The purpose of this study is to analyze the relationship of technology innovation and perceived service quality with the internal marketing factors in the communication industry and to offer suitable and effective internal marketing suggestions. The independent variables of this study are internal communication, education and training, the support of the executives, reward systems, and empowerment. The dependent variables are technology innovation and perceived service quality. Utilizing these, this paper studies the influence of internal marketing factors on technology innovation and perceived service quality. Results - The study results revealed the following. First, the identified internal marketing factors have a positive effect on technology innovation. Among the five internal marketing factors, three had a significant effect on product innovation, empowerment, the support of executives, and education and training, in this order. Second, the internal marketing factors also had a positive effect on the process innovation of technology innovation. The marketing factors, the support of executives, empowerment, internal communication, and education and training, in this order, significantly affect process innovation. Third, technology innovation had a positive effect on perceived service quality. All of the five service quality factors, namely, tangibles, reliability, assurance, responsibility, and empathy, in this order, significantly affect product innovation. Additionally, tangibles, reliability, responsibility, empathy, and assurance, in this order, significantly affect process innovation. Fourth, product and process innovation significantly affect tangibles and reliability in technology innovation. To enhance tangibles and reliability, process innovation should first be enhanced. Fifth, product and process innovation significantly affect responsibility and empathy in technology innovation. To enhance the responsibility and empathy, process innovation should first be enhanced. Sixth, product and process innovation significantly affect assurance in technology innovation. To enhance the assurance, product innovation should first be enhanced. Conclusions - According to the results, a company's internal marketing factors have a positive and significant effect on technology innovation and, further, product and process innovation have a positive and significant effect on the perceived serviced quality.

• Journal of Distribution Science
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• v.11 no.10
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• pp.81-92
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• 2013

Purpose - This study empirically analyzes the effect of improvements in the quality of service management performance of college education on traders' conscious change of business management innovation and diverse sales expertise for a year. The use of traders' conscious changes and sales expertise as variables for the verification of the effects of parameters related to the active trader's traditional education market is a desirable direction. The method of research reflects the quality of education service, management result, traders' conscious changes, and sales expertise to understand the precise essence and definition of teaching quality at merchant colleges through theoretical consideration. Moreover, its impact on traders' conscious changes and sales expertise in empirical analysis acts as an intermediary. Research design, data, methodology - The hypothesis of this study leverages the SPSS statistical program. To gather actual proof, sample survey for theoretical research examined 262 valid papers of the 300 papers written by 10 merchants who graduated from merchant's university. First, using the SERVQUAL model, Parasuraman et al. (1996) indicated that for quality of education service, the configuration of factors is the same as the sympathetic performance, that is, responsiveness and empathy, and traders are aware of these elements. However, our preliminary investigation revealed that traders' university education has been excluded as a component of quality of service in the earlier studies. Moreover, we found that certainty of knowledge, reliability, and sympathy are influenced by challenges and by the changing intentions of merchant consciousness. In addition, our study confirms that improvements in convincing abilities and sales technique have a positive impact. Second, merchants' and traders' expertise are proven to affect business performance. In other words, university education of traders and merchants affects the consciousness of consumers, and changes patterns of sales. Third, the quality of service management education and change in the consciousness has a considerable impact on the trader, thereby maximizing business performance and acting as an intermediary for verification. Fourth, the quality of service management education affects the trader's sales expertise to maximize business performance. Results - To summarize, the quality of college educational services relates to the improvement of business performance and the role of the resulting virtuous cycle. Consequently, we can look for suggestions in the traditional markets, where the Government pays attention to the exterior environmental factors as well as to the changing business environment. However, the most important aspect is the merchant awareness. That is, a merchant should understand the distribution environment. Several competitor and trend analyses should be conducted to meet customers' expectations positively and proactively cope with any challenges related to changes. Further, expertise in sales and marketing skills need to be acquired to improve customer convincing abilities and develop a customer-oriented mindset. Conclusions - According to the changes in consumption trends of business enterprises, new management techniques are required to survive competition by improving traditional markets, which will necessitate more competitive education programs in merchant universities.

• The Journal of Industrial Distribution & Business
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• v.8 no.5
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• pp.95-109
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• 2017

Purpose - The purpose of this study is to classify the quality factors of coffee shop customers with the service quality based on the SERVQUAL, selection attributes, and service qualities used in previous studies. The path structure of coffee shops' quality factors → customer satisfaction → trust → behavioral intention was analyzed in order to confirm the system of coffee shops' quality factors. Research design, data, and methodology - The survey of was conducted with college students of Kangwon University. A total of 250 questionnaires were distributed, with 232 collected. Of them, Excluding 36 respondents' because of incomplete answers and missing values, 196 responses were used in the final analysis. Empirical analysis was made through factor analysis, correlation analysis, multiple regression analysis, simple regression analysis and mediating regression analysis by using Statistics Package SPSS 19.0. Results - The results are as follows: Firstly, coffee shops' quality factors were classified into seven categories like service encounter quality, product quality, cleanliness, overall interior, purchase quality, convenience, and aesthetics. Secondly, service encounter quality, product quality, purchase quality, and aesthetics had a positive effect on customer satisfaction, respectively. Thirdly, it showed that service encounter quality, product quality, overall interior, purchase quality, and aesthetics had a positive effect on trust, respectively. Fourthly, customer satisfaction had a positive effect on behavioral intention. Lastly, after verifying the effect relations of trust between customer satisfaction about coffee shop and behavioral intention, customer satisfaction has a positive effect on trust and trust has a positive effect on behavioral intention. On the other hand, trust did not have a mediating effect between customer satisfaction and behavioral intention. But, cleanliness, convenience, and overall interior did not have a positive effect on customer satisfaction. Conclusions - Coffee shop consumers put importance on price, discount systems, taste, and freshness, but more on courteous and kind services of coffee shop staff or comfortable and calming atmosphere of inner space. Thereby, coffee shop marketers need to take factors like service encounter quality and aesthetics into more consideration. In addition, customer satisfaction has an effect on trust, while trust on behavioral intention, even though trust is not mediated between customer satisfaction and behavior intention.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.2
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• pp.5-28
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• 2009

The purpose of this study is to investigate the use of the electronic information resources of humanities scholars in Korea and propose the planning of academic library and information services to serve their needs. To collect data, a postal survey was conducted during the period of November 2007 through January 2008. Out of 799 humanities scholars sampled from 25 universities, 132 responded with a completion rate of 16%. The major findings of this study are as follows: Firstly, the majority of humanities scholars distribute their time equally between research and education, and conduct independent research. Secondly, they use, to a certain degree, electronic information resources largely in text format, and depend upon the electronic collection of their academic libraries. Thirdly, with the exception of a couple of sources of electronic journal resources, the electronic resources that these humanities scholars regularly use vary so widely that none could be considered to be a common resource. Fourthly, they value the convenience of accessing and using electronic resources, but worry about the quality and scope of the contents. It is suggested that academic libraries (1) become the gateway for the electronic information that is available both inside and outside the library, (2) provide integrated search feature for and a 'single sign on' access to electronic resources, and (3) plan customized user education for specific subject fields in the humanities.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.115-123
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• 2013

Food safety management should be based on scientific evidences. FAO and WHO presented risk analysis as one of four principles in food safety management. WTO also admits the self safety regulation only when it is made on the basis of risk assessment. Without scientific analysis, tracing and eliminating the cause of food poisoning is impossible. Research and development plays a key role to produce scientific evidences. The Korean government ran over 40 programs in 11 agencies from 2008 to 2010. However, there is no statistics on food safety R&D at present. In this research, food safety projects conducted from 2008 to 2010 are listed up by means of analysing National Science and Technology Information Service (NTIS). The analytical criteria are the name of programs, national standard classification of science and technology, and keywords. As result, Korea Food and Drug Administration, Ministry for Food, Agriculture, Forestry and Fisheries, and Rural Development Administration play major role in the food safety R&D. The portion of more than one year projects should rise up in order to achieve the data for risk assessment, which is strongly required to improve. Besides, the research should be deeper so as to publish more SCI papers. The R&D portfolio should be changed in direction to raise up the portion of biological hazards such as norovirus. In order to do so, a large number of food safety programs should be emerged. The categories of food safety management and the hygiene/quality management of the agricultural and livestock products in the national standard classification of science and technology should be emerged because they are set up reflecting agencies' interests in spite of few differences between them.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.11a
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• pp.154-154
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• 2003

세계의 특허동향을 분석해 보면 수처리용 MF/UF 분리막의 제조 및 응용에 관한 연구개발이 매우 활발하게 진행되어져 왔음을 알 수 있다. 또한 다국적 기업들의 적극적인 마케팅과 분리막 공법의 우수한 처리효율이 인정되면서 90년대 후반부터는 수십만톤/일 규모의 징수처리 및 하수고도처리 분야에까지 MF/UF 분리막이 괄목할만한 수요의 증대를 보이고 있으며 이러한 추세는 앞으로도 더욱 확대될 것으로 전망이 되고 있다. 고분자재료를 이용하여 MF/UF 분리막을 제조하는 방법으로는 보편적으로 첫째, 고분자를 용매에 녹인 후 용매와 비 용매간의 상호교환을 유도하여 분리막을 제조하는 상전이법(Phase Inversion). 둘째, 고분자를 고온에서 희석제와 melt-blending 한 후 가해진 열을 제거하면서 상분리를 일으켜 다공성을 부여하는 열유도 상분리법(TIPS, Thermally Induced Phase Separation). 셋째, 결정성 고분자를 용융, 압출 및 냉각하여 결정화도가 매우 높은 전구체를 제조한 후 연신에 의해 비결정 영역을 개열시켜 기공을 형성하는 연신법(Stretching process)이 있다. 이 중 물성이 매우 우수한 폴리올레핀계 결정성 고분자를 이용하여 분리막을 제조할 수 있는 방법은 열유도 상분리법 및 연신법에 제한된다. 본 연구 발표에서는 세계적으로도 극소수의 기업들만이 보유하고 있으며 고도로 축적된 노하우를 필요로 하는 열유도 상분리법 및 연신법에 의하여 폴리프로필렌 및 폴리에틸렌 중공사막을 제조하는 방법과 이 두 가지 방법에 의해서 제조된 중공사막의 구조, 물성 및 수투과 성능 그리고 KMS 중공 사막의 응용사례를 통한 실제 운전특성 등을 소개하고자 한다.좋은 결과를 가져다 주는 술식으로 판단되었다.결과를 이용하여 향후 전개될 홈 네트워크 서비스 및 관련시장의 발전 방향을 전망해 보고 이에 따른 기업이나 정부차원의 대응전략을 파악하고자 한다.육구에서는 큰 변화를 나타내고 있지 않았다(p<0.05). 운동과 비운동시킨 참돔의 지질 함량의 변화는 운동시킨 참돔은 운동으로 인한 에너지 소비로 인하여 함량이 유의적으로 감소했으며(r=-0.35), 비운동사육구에서는 절식으로 인하여 지질함량이 감소하였다(r=-0.38). 파괴강도와 가장 밀접한 영향을 가지는 콜라겐은 운동과 비운동 모두 사육기간동안 큰 변화는 보이지 않았다. 초기의 파괴강도값은 1.45±0.02kg(운동사육구), 1.36±0.18kg(비운동사육구)이였으며 사육기간동안 운동사육구는 파괴강도값이 증가한 반면, 비운동수조에서는 참돔의 파괴강도는 사육기간동안 큰 유의차가 없었다. 각 성분간의 상관도를 살펴보면, 수분함량과 파괴강도는 상관성을 가졌으며, 지질함량과 파괴강도도 같은 경향은 나타내었다. 운동기간동안의 파괴강도와 콜라겐 사이에는 상관성의 거의 없었다. 이는 운동기간에 따른 파괴강도의 증가가 콜라겐의 함량의 증가보다는 지질함량의 감소와 수분함량의 증가와 같은 성분과의 상관성이 크다고 판단된다. 다음으로는, 운동횟수에 의한 영향으로써 운동시간을 1일 6시간으로 설정하여, 운동횟수를 결정하기 위하여 오전, 오후에 각 3시간씩 운동시키는 방법과 오전부터 6시간동안 운동시키는 두 방법을 이용하여 품질을 비교하였다. 각 조건에 따라 운동시킨 참돔의 수분함량을 나타낸 것으로, 2회(오전 3시간, 오후 3시간)에 나누어서 운동시키기 위한 육의 수분함량은 73.37±2.02%를 나타냈으며, 1회(6시간 운동)

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.5
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• pp.243-254
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• 2005

Soft real-time applications such as multimedia feature highly variable processor requirements and probabilistic guarantees on deadline misses, meaning that each task in the application meets its deadline with a given probability. Thus, for such soft real-time applications, a system designer may want to improve the system utilization by allocating to each task a processor time less than its worst-case requirement, as long as the imposed probabilistic timing constraint is met. In this case, however, we have to address how to schedule jobs of a task that require more than (or, overrun) the allocated processor time to the task. In this paper, to address the overrun problem, we propose an overrun control method, which probabilistically controls the execution of overrunning jobs. The proposed overrun control method probabilistically allows overrunning jobs to complete for better system utilization, and also probabilistically prevents the overrunning jobs from completing so that the required probabilistic timing constraint for each task can be met. In the paper, we show that the proposed method outperforms previous methods proposed in the literature in terms of the overall deadline miss ratio, and that it is possible to synthesize the scheduling parameters of our method so that all tasks can meet the given probabilistic timing constraints.