• Journal of KIISE:Computer Systems and Theory
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• v.37 no.5
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• pp.292-303
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• 2010

On-chip cache memories play an important role in both performance and energy consumption points of view in resource-constrained embedded systems by filtering many off-chip memory accesses. We propose a 2-level data cache architecture with a low energy-delay product tailored for the embedded systems. The L1 data cache is small and direct-mapped, and employs a write-through policy. In contrast, the L2 data cache is set-associative and adopts a write-back policy. Consequently, the L1 data cache is accessed in one cycle and is able to provide high cache bandwidth while the L2 data cache is effective in reducing global miss rate. To reduce the penalty of high miss rate caused by the small L1 cache and power consumption of address generation, we propose an ECP(Early Cache hit Predictor) scheme. The ECP predicts if the L1 cache has the requested data using both fast address generation and L1 cache hit prediction. To reduce high energy cost of accessing the L2 data cache due to heavy write-through traffic from the write buffer laid between the two cache levels, we propose a one-way write scheme. From our simulation-based experiments using a cycle-accurate simulator and embedded benchmarks, the proposed 2-level data cache architecture shows average 3.6% and 50% improvements in overall system performance and the data cache energy consumption.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.535-546
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• 2000

Juam lake is a major water resource for the industrial and agricultural activities as well as the resident life of Kwangju and Chonnam area. However, the water quality of the lake is getting worse due to a large quantity of pollutant inflowing to the lake. As a preliminary step in making the countermeasure to achieve the water quality goal of the lake. it is necessary to understand how the water quality of the lake will be in future. Several computer programs can be used to predict the water quality of lake. Each of these programs requires a number of input data such as hydrological and meteorological data. and the quantity of the pollutant inflowed. but some or most of the input data contain uncertainty. which eventually results in the uncertainty of prediction value (future level of water quality). Generally. the uncetainty stems from the lack of information available. the randomness of future situation. and the incomplete knowledge of expert. Thus. the purpose of this study is to present a method for representing the degree of the uncertainty contained in input data by applying fuzzy theory and incorporating it directly into the water quality modeling process. By using the method. the prediction on the future water quality level of Juam lake can be made that is more appropriate and realistic than the one made without taking uncertainty in account.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.3
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• pp.140-148
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• 2009

Recent advances in communication and multimedia technologies make it possible to provide video-on-demand(VOD) services and people can access video servers over the Internet at any time using their electronic devices, such as PDA, mobile phone and digital TV. Each device has different processing capabilities, energy budgets, display sizes and network connectivities. To support such diverse devices, multiple versions of videos are needed to meet users' requests. In general cases, VOD servers cannot store all the versions of videos due to the storage limitation. When a device requests a stored version, the server can send the appropriate version immediately, but when the requested version is not stored, the server first converts some stored version to the requested version, and then sends it to the client. We call this conversion process transcoding. If transcoding occurs frequently in a VOD server, the CPU resource of the server becomes insufficient to response to clients. Thus, to admit as many requests as possible, we need to maximize the CPU availability. In this paper, we propose a new algorithm to select versions from those stored on disk using a branch and bound technique to maximize the CPU availability. We also explore the impact of these storage management policies on streaming to heterogeneous users.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.8
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• pp.984-998
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• 1999

최근 개인 휴대 통신에 대한 관심도가 증가하면서 B-ISDN (Broadband Integrated Services Digital Network)과 같은 기존의 유선 망에서 제공하던 다양한 멀티미디어 응용 지원을 무선 망으로 확장시키기 위한 연구가 활발히 진행되고 있다. 그러나 기존의 유선 망에서는 멀티미디어 응용 지원을 위해 QoS (Quality of Service) Provisioning에 관한 많은 연구가 되어 있으나 무선 망에서는 이동성과 무선 전파의 열악한 전송으로 인해 새로운 QoS Provisioning 방법에 관한 연구가 필수적이다. 본 논문에서는 이러한 무선 망의 특수성으로 인해 발생할 수 있는 서비스의 질 저하와 강제 종료를 줄임으로써 지속적인 QoS를 보장해 주고 한정된 무선 자원을 효율적으로 사용하며 처리에 의한 오버헤드를 줄이기 위하여 다음과 같은 세 가지 방법을 제안하였다. 첫째, 핸드오프 강제 종료율을 줄이기 위하여 대역폭 예약 방법을 사용하되 특정 셀의 트래픽 특성에 맞게 또한 시간대에 따른 트래픽 특성에 따라 예약 대역폭의 양을 조절하는 적응적 대역폭 예약 방법이다. 둘째, 많은 경우 각 셀의 트랙픽 변화는 일정한 주기로 변화한다는 특성에 따라 과거의 트래픽 정보를 이용하는 예측 기반의 대역폭 예약 방법이다. 마지막으로 호의 종류, 트래픽 특성, 단말기의 이동 속도에 따라 다른 우선 순위에 의해 호 수락 제어를 수행하는 우선 순위 기반의 호 수락 제어를 제안하였다. 시뮬레이션을 통하여 기존에 제안된 방법과 성능 비교하여, 요구되는 수준의 QoS 보장과 효율적인 자원의 사용, 요구되는 처리비용의 최소화를 통해 전체 시스템의 성능 향상을 입증하였다.Abstract As interest in wireless hand-held terminals and in personal communications services increases recently, there have been broad studies on the ways to support multimedia applications provided in wired networks such as B-ISDN (Broadband Integrated Services Digital Network) in wireless networks. However, since many studies have focused on Quality of Service (QoS) Provisioning in wired networks to provide multimedia applications, new methods of QoS Provisioning are needed in wireless networks to resolve the problem of wireless channel fading and the difficulty of mobility occurred in wireless networks. This paper proposes three schemes of QoS Provisioning in wireless networks which will make continuous QoS guarantee and efficient use of limited wireless resources possible. The first scheme reserves bandwidth in proportion to the amount of real-time traffic in the neighbor cells to decrease the handoff dropping rate of delay sensitive real-time connections, adapting reserved bandwidth for efficient resource utilization. The second scheme is predictive bandwidth reservation scheme that utilizes the past handoff information. It can decrease overheads required to adapt bandwidth reservation. The last scheme is priority-based call admission control prioritizing traffic type (real-time traffic/ non-real-time traffic), connection type (new connection /handoff connection), and mobile terminal speed (fast mobile/slow mobile). Simulation results show that the proposed QoS Provisioning schemes improve the total system performance by achieving three goals - required QoS guarantee, higher bandwidth utilization and less overhead.

• International Commerce and Information Review
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• v.19 no.2
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• pp.213-236
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• 2017

World trade has entered a stagnant state, protection trade measures are spread due to delayed economic recovery in developed countries, sluggish investment in emerging economies such as China, economic recession in resource exporting countries, and geopolitical and political uncertainties along with the election period in the US and other major industrialized countries. Thus, in the economic structure of our country with a focus on export, for small and medium enterprises to grow, efforts for having various markets are necessary. The importance of the trade insurance system, which can support the risk management of enterprises, is emphasized by the fact that the majority of SME exporters have a risk management level and a lack of corporate capacity to enter the global market. This study was surveyed with 87 small and medium export companies in South Korea. The purpose of this study is to verify the effect relationship how service quality of trade insurance and utilization of trade insurance impact on the risk management of trade payment and export performance. The research hypothesis and model was derived from the basis of existing theory and empirical research, and obtained the following results. Firstly, Service Quality of Trade Insurance showed positive (+) effect on Export Performance. Secondly, Utilization of Trade Insurance showed positive (+) effect on Risk Management of Trade Payment. Thirdly, Risk Management of Trade Payment showed positive (+) effect on Export Performance. This study is differentiated from previous research information by empirically evaluating the relationship between the risk management of trade payment and export performance through utilization of trade insurance. This study contributed to academic by examining the research on the risk management of trade insurance and also practically suggested the direction how small and medium export company is to take the advantage of the trade insurance.

• Korean Journal of Social Welfare
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• v.54
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• pp.35-64
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• 2003

This study is to explore experience on the inter-organizational linkages for vocational rehabilitation of people with psychiatric disabilities and to find out predictors affecting the linkages. This study used triangulation a way as to combine the advantages of both the qualitative and the quantitative approach. The qualitative approach is based on grounded theory by Strauss & Cobin. The quantitative research used the samples of 122 organizations, and was analyzed by multiple regression & logistic regression. The results are as follows. First, as results of in-depth interview, interviewees perceived linkage experience as 'turning the eyes on the other organization in community', namely 'the pursue of collaboration'. This concept is classified four types: initiative, cooperative, authoritative and passive type. Second, according to Tobin(1986)'s five phase of the closeness of inter-organizational linkages, our linkages were found to be in third phase, "coordination". Finally, predictors of the attempt of having linkages & linkage strengthening were analyzed by logistic regression & multiple regression. 'The experience of professional training on people with psychiatric disabilities' and 'the resource dependency' have statistically significant relation with the attempt to have linkages. 'The length of current service', 'the experience of professional training on people with psychiatric disabilities', and 'recognition about other organizational activities' are significantly related to strengthening linkage. Based on the results of this study, alternatives for promoting inter-organization linkages for vocational rehabilitation of people with psychiatric disabilities were proposed.

• The Journal of Korean Medical History
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• v.24 no.2
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• pp.25-55
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• 2011

The currently existing "Bonchojeonghwa (本草精華)" is a manuscript without the preface and the epilogue, composed of 2 books in 2 volumes. This book is a quintessence of knowledge on science of medicinal ingredients (medicinal phytology I herbal science) as well as an trial of new development in Chosun medical science. I.e. this book includes surprising change representing medical science in Chosun dynasty as a single publication on science of medicinal ingredients. It holds a value essential to clinician as a specialized book in medicinal ingredients, and Includes richer content on medicinal ingredients than any other books published before. In addition, it is away from boring list-up of superfluous knowledge as seen in "Bonchokangmok(本草綱目)" published in China, and well summarizes essential knowledge which can be used within a range of medicines available in Korea. This book has an outstanding structure that can be even used in today's textbook on science of medicinal ingredients, as it has clear theory, system and classification. Because it handles essential learning points prior to prescription to disease, it is possible to configure new prescription and adjustment of medicinal materials. Moreover, this book can play a good role for linguistic study at the time of publication, because it describes many drugs in Hangul in many parts of the book. "Bonchojeonghwa" includes a variety of animals, plants and mineral resources in Korea, like "Bonchokangmok" which was recently listed in UNESCO. As such, it has a significance in natural history as well as pharmacy in Korean Medicine. It has various academic relationships all in biologic & abiologic aspects. It has importance in sharing future biological resources, building up international potential, setting up the standard for biologic species under IMF system, and becoming a base for resource diplomacy. We should not only see it as a book on medicinal ingredients in terms of Oriental Medicine, but also make an prudent approach to it in terms of study strengthening Korea's national competitiveness. After bibliographical reviewing on the features & characteristics of the only existing copy of "Bonchojeonghwa" housed in Kyujanggak(奎章閣) of Seoul National University, the followings are noted. First, "Bonchojeonghwa" is a specialized book on medicinal ingredients voluntarily made by private hands to distribute knowledge on drugs in the desolate situation after Imjinoeran (Japanese Invasion in 1592), without waiting for governmental help. Second, it raised accessibility and practicality by new editing. Third, it classified 990 different kinds of drugs into plant, animal, and mineral at large, and dassified more in detail into 15 'Bu' and 48 'Ryu' at 258 pages. Fourth, the publication of this book is estimated to be around 1625~1633, at the time of Injo's reign in 17th century. Fifth, it contains the existing & up-to-date knowledge at the time of publication, and it is possible to see the supply-demand situation by Hangul descriptions in 149 places in the book. By the fact that there are many linguistic evidences of 17th century, explains well when the book was published.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.357-370
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• 2011

Using strategy group theory, this thesis reviewed the status of program providers analysis and the performances it has made so far, and sought measures to improve its limitations. The constraint of program providers analysis based on existing concept of strategy group is that the strategy group was derived from the statistics, and therefore only applied the characteristics of program provider's channels to the analysis, on account of which a systematic and sophisticated classification as well as generalization of strategy or strategy group were hard to obtain. Moreover, the PP strategy variables used to be selected at the firm level and business level, and in relation with resource and competition scope. In future, more appropriate procedure should be followed to obtain objectivity in selecting variables to avoid controversy over intentionality. The measures in this thesis to improve the study of PP strategy group can be summarized as follows: firstly analysis of variables for strategy group classification should be made to single out key variables which are to be classification criteria. Secondly, variables are to be cross-checked by industry experts to increase generalizability. Thirdly, proxy variables should be sublated, and strategy group model which enables the reflection of subsistent properties of PP industry, and the cognitive perception of the executives(CEO) needs to be established. Fourthly, the concepts of mobility barrier and isolating mechanism should be applied to the classification criteria of strategy group to reveal the gap of performance between different strategy groups. Lastly, chronicle study on PP strategy group should be done to perceive the dynamic changes of PP strategy group.

• Journal of Digital Contents Society
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• v.9 no.4
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• pp.591-600
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• 2008

Korean traditional culture has a long history and it is rooted in the deep down our national culture. It is like bread and pride for Korean people. The tale of Cheyong is a precious cultural heritage, which has existed in the public awareness of the Korean people since the period of unified Silla. Based on its mysterious and beautiful story, the value of traditional culture can be revealed through development of digital contents. With such precious cultural resource we can digitalize the fun contents which the general public can enjoy. Ways of digitalize of cultural archetype has been suggested by analyzing the content elements of the tale of Cheyong. Also, by making scientific approach to the development process of digitalization, the possibility of digitalization has been found through 3D animation restoration process for Cheyong Dance and the process of making the tale of Cheyong into animation. Through analyzing the contents development process of cultural archetype of the tale of Chetyong, a cultural archetype sourcehas been developed which has a great value as a contents product that can be developed and used as various cultural content art works. With studies on the theory of development method for digitalization of traditional culture, scientific studies and investigation have to be continuously carried out so the digitalization of Korean cultural heritage, which will shine in the world, can be continued as well.

• Journal of the Korean Geographical Society
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• v.39 no.5 s.104
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• pp.735-754
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• 2004

This paper provides an overview of political ecology, a body of theory that focuses on the links between political and economic inequality on the one hand, and environmental degradation on the other. Adopting a tripartite classification scheme that identifies three political ecology traditions -'classical', 'democratic' and 'poststructuralist'- the discussion shows the need for a move within the poststructuralist tradition away from a narrow and quasi-idealistic focus on discourse to a more robust philosophical engagement with ontological and epistemological issues grounded in Gilles Deleuze's development of Nietzschean materialism. From there. the author draws on numerous examples from Canada, and surveys the available literature on 'bioregionalism', a relatively new intellectual tradition evolved from the North American environmental social movements of the 1970s and 1980s. The so-called 'bioregional approach' stresses that administrative units need to reflect (rather than transect) eco-geographical and cultural features. Bioregionalism is described and assessed as a potential pragmatic research framework for geographers and other planners wishing to respond proactively to the call for a revamped, poststructuralist political ecology. The paper concludes that a bioregional approach to political ecology avoids the weaknesses identified by certain critics, provides scope for consideration of fundamental philosophical ideas, and as such, represents a practical development of a poststructuralist political ecology.