• Title/Summary/Keyword: Cluster System

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CHARACTERISTICS OF HETEROEPITAXIALLY GROWN $Y_2$O$_3$ FILMS BY r-ICB FOR VLSI

  • Choi, S.C.;Cho, M.H.;Whangbo, S.W.;Kim, M.S.;Whang, C.N.;Kang, S.B.;Lee, S.I.;Lee, M.Y.
    • Journal of the Korean institute of surface engineering
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    • v.29 no.6
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    • pp.809-815
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    • 1996
  • $Y_2O_3$-based metal-insulator-semiconductor (MIS) structure on p-Si(100) has been studied. Films were prepared by UHV reactive ionized cluster beam deposition (r-ICBD) system. The base pressure of the system was about $1 \times 10^{-9}$ -9/ Torr and the process pressure $2 \times 10^{-5}$ Torr in oxygen ambience. Glancing X-ray diffraction(GXRD) and in-situ reflection high energy electron diffracton(RHEED) analyses were performed to investigate the crystallinity of the films. The results show phase change from amorphous state to crystalline one with increasingqr acceleration voltage and substrate temperature. It is also found that the phase transformation from $Y_2O_3$(111)//Si(100) to $Y_2O_3$(110)//Si(100) in growing directions takes place between $500^{\circ}C$ and $700^{\circ}C$. Especially as acceleration voltage is increased, preferentially oriented crystallinity was increased. Finally under the condition of above substrate temperature $700^{\circ}C$ and acceleration voltage 5kV, the $Y_2O_3$films are found to be grown epitaxially in direction of $Y_2O_3$(1l0)//Si(100) by observation of transmission electron microscope(TEM). Capacitance-voltage and current-voltage measurements were conducted to characterize Al/$Y_2O_3$/Si MIS structure with varying acceleration voltage and substrate temperature. Deposited $Y_2O_3$ films of thickness of nearly 300$\AA$ show that the breakdown field increases to 7~8MV /cm at the same conditon of epitaxial growing. These results also coincide with XPS spectra which indicate better stoichiometric characteristic in the condition of better crystalline one. After oxidation the breakdown field increases to 13MV /cm because the MIS structure contains interface silicon oxide of about 30$\AA$. In this case the dielectric constant of only $Y_2O_3$ layer is found to be $\in$15.6. These results have demonstrated the potential of using yttrium oxide for future VLSI/ULSI gate insulator applications.

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A Performance Improvement Scheme for a Wireless Internet Proxy Server Cluster (무선 인터넷 프록시 서버 클러스터 성능 개선)

  • Kwak, Hu-Keun;Chung, Kyu-Sik
    • Journal of KIISE:Information Networking
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    • v.32 no.3
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    • pp.415-426
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    • 2005
  • Wireless internet, which becomes a hot social issue, has limitations due to the following characteristics, as different from wired internet. It has low bandwidth, frequent disconnection, low computing power, and small screen in user terminal. Also, it has technical issues to Improve in terms of user mobility, network protocol, security, and etc. Wireless internet server should be scalable to handle a large scale traffic due to rapidly growing users. In this paper, wireless internet proxy server clusters are used for the wireless Internet because their caching, distillation, and clustering functions are helpful to overcome the above limitations and needs. TranSend was proposed as a clustering based wireless internet proxy server but it has disadvantages; 1) its scalability is difficult to achieve because there is no systematic way to do it and 2) its structure is complex because of the inefficient communication structure among modules. In our former research, we proposed the All-in-one structure which can be scalable in a systematic way but it also has disadvantages; 1) data sharing among cache servers is not allowed and 2) its communication structure among modules is complex. In this paper, we proposed its improved scheme which has an efficient communication structure among modules and allows data to be shared among cache servers. We performed experiments using 16 PCs and experimental results show 54.86$\%$ and 4.70$\%$ performance improvement of the proposed system compared to TranSend and All-in-one system respectively Due to data sharing amount cache servers, the proposed scheme has an advantage of keeping a fixed size of the total cache memory regardless of cache server numbers. On the contrary, in All-in-one, the total cache memory size increases proportional to the number of cache servers since each cache server should keep all cache data, respectively.

Design and Implementation of Initial OpenSHMEM Based on PCI Express (PCI Express 기반 OpenSHMEM 초기 설계 및 구현)

  • Joo, Young-Woong;Choi, Min
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.3
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    • pp.105-112
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    • 2017
  • PCI Express is a bus technology that connects the processor and the peripheral I/O devices that widely used as an industry standard because it has the characteristics of high-speed, low power. In addition, PCI Express is system interconnect technology such as Ethernet and Infiniband used in high-performance computing and computer cluster. PGAS(partitioned global address space) programming model is often used to implement the one-sided RDMA(remote direct memory access) from multi-host systems, such as computer clusters. In this paper, we design and implement a OpenSHMEM API based on PCI Express maintaining the existing features of OpenSHMEM to implement RDMA based on PCI Express. We perform experiment with implemented OpenSHMEM API through a matrix multiplication example from system which PCs connected with NTB(non-transparent bridge) technology of PCI Express. The PCI Express interconnection network is currently very expensive and is not yet widely available to the general public. Nevertheless, we actually implemented and evaluated a PCI Express based interconnection network on the RDK evaluation board. In addition, we have implemented the OpenSHMEM software stack, which is of great interest recently.

The Parallelization Effectiveness Analysis of K-DRUM Model (분포형 강우유출모형(K-DRUM)의 병렬화 효과 분석)

  • Chung, Sung-Young;Park, Jin-Hyeog;Hur, Young-Teck;Jung, Kwan-Sue
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.4
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    • pp.21-30
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    • 2010
  • In this paper, the parallel distributed rainfall runoff model(K-DRUM) using MPI(Message Passing Interface) technique was developed to solve the problem of calculation time as it is one of the demerits of the distributed model for performing physical and complicated numerical calculations for large scale watersheds. The K-DRUM model which is based on GIS can simulate temporal and spatial distribution of surface flow and sub-surface flow during flood period, and input parameters of ASCII format as pre-process can be extracted using ArcView. The comparison studies were performed with various domain divisions in Namgang Dam watershed in case of typoon 'Ewiniar' at 2006. The numerical simulation using the cluster system was performed to check a parallelization effectiveness increasing the domain divisions from 1 to 25. As a result, the computer memory size reduced and the calculation time was decreased with increase of divided domains. And also, the tool was suggested in order to decreasing the discharge error on each domain connections. The result shows that the calculation and communication times in each domain have to repeats three times at each time steps in order to minimization of discharge error.

Research on development plan of medium and long period of Vocational Education for Chungbuk (충청북도 직업교육 중·장기발전 방안)

  • Oh, SeongKyeun;Uh, SangHo;Eun, TaeWook;Kim, JinKyun;Kim, JinSoo
    • 대한공업교육학회지
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    • v.31 no.1
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    • pp.146-169
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    • 2006
  • 'VEC 2010' is a mid-long term scheme on the development of Vocational Education for Chung-buk which is to be accomplished by 2010. On the basis of this scheme, schools adopt 3-Type curriculum considering their conditions and covert themselves into specialized high school which is associated with local industry cluster. They also establish combined high schools which run various curriculums emphasizing basic vocational abilities so that they can meet the needs of demanders The activation plan of Chung-buk province vocational education is a dualized one which is for both ongoing education for entrance into a school of higher grade and the last education for employment, which is supposed to foster the human resources required by the knowledge-based society in the 21st century. The specific contents of 'VEC 2010' is as follows. First, VEC 2010 presents 2 kinds of mid-long term management system for industrial high schools: general industrial high school, specialized high school(single type, combined type). Second, VEC 2010 arranges and run the 3-Type of curriculum of Chung-buk province industrial high schools: employment-centered type, entering higher school-centered type, inaugurating enterprise-centered type. Third, VEC 2010 divides Chung-buk province industrial high schools into 4 districts and suggests mid-long term reorganization plan of system. Fourth, VEC 2010 suggests the substantial strategies of Chung-buk province vocational education: scholarship improvement in the vocational investigation course of the government-sponsored scholastic aptitude test, education for improving basic vocational abilities, substantial management of joint laboratory, administrative and financial support of development of specialized, licensed textbooks. reenforcement of career education.

Promoting Technology Convergence in Industrial Clusters through Intellectual Property Service Center (산업클러스터 기술융합 활성화를 위한 효율적인 지식재산서비스 지원 방안 연구)

  • So, Byeong-Woo;Gong, Byeong-Yeong
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.6 no.1
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    • pp.133-158
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    • 2011
  • In 2030s, as we enter in to the era of BT (Bio-Technology) market opening up, technologies in all areas such as IT, data analysis, IC and biochemistry are necessitated. New development in technology will be based on "Convergence", especially between IT and BT. In order to have synergy effects from the convergence, those related industries and universities should be physically inter-related in an appropriate location. Until 2009, 819 industrial clusters where many Korean industries and firms are concentrated have been constructed in Korea. They have had supports from various institutions and facilities. However, few systems designed to assist "intellectual property (IP) service" for technology convergence are found in Korea. Thus, by analyzing current problems and challenges of the Korean industrial clusters, this paper suggests a possible answer to maximize the synergy from technology convergence through organic cooperation among companies in industrial clusters. This paper finds that the Korean industrial clusters need to establish IP service supporting center while suggesting its function and concept on organization structure, and work flow, which help firms to develop IP strategies. In addition, the paper provides a direction for current IP system and policies implemented by the Korean government to be more effective to small-and-medium-sized companies located in the industrial clusters.

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A Study on Social Supports for the Elderly Housing in Senior Concentrated Cities in the United States and Canada : Focused on Small Cities along Rural Counties (미국과 캐나다 노인밀집도시의 노인주거관련 사회적지원에 관한 연구 : 농촌지역 소도시를 중심으로)

  • Lee, In-Soo
    • Journal of Families and Better Life
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    • v.29 no.3
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    • pp.23-41
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    • 2011
  • The purpose of this study is to explore social supports for elderly housing and their residential lives in small cities along rural counties of the United States and Canada, and suggest future implications for age-concentrated rural villages in Korea. In this study, five small and medium cities in non-metropolitan counties of California and Ontario province were visited and elderly residents and service experts were interviewed about their perceptions of community integrated social support networks for senior residences. The senior housing complexes were built due to influx of both metropolitan and rural residents seeking warm localities, traffic connections, business purposes in active production areas. and leisure attractions. There are five main social support networks for senior housing issues in these areas. First, the areas are claimed for senior zones and accordingly health industries are encouraged by local authorities. Second, the community is homogeneously constructed as a senior friendly environment and include features such as an RV park and mobile cottages. Third, senior-helping seniors are offered active work through golf-cluster active retirement communities. Fourth, traditional theme production camps are mobilized by the elderly workers. Lastly, an information system is maintained for screening volunteers and for senior abuse prevention. On the other hand, residential lives are occasionally negatively influenced by unbalanced concentrations of elderly facilities such as nursing stations and funeral homes. For the future of Korean rural elderly policies, suggestions are made as follows: first, an integrated urban and rural township that contains attractive places for early retiring people who seek a warm atmosphere in later life needs to be constructed. Second, an integrated model retirement village of urban and rural retirement life needs to be initiated as a measure of evaluating the adaptation process of movers in senior concentrated zones. Third, a cooperation system among governmental ministries needs to be formed with the long- term goal of establishing a traditional rural town of independent housing districts and medical facilities in rural areas. Fourth, productive and active lifestyles need to be maintained as the local community and government develop successful retirement rural villages, by limiting the expansion of nursing related facilities. Finally, generation integrated visiting welfare programs and services need to be further developed for the housing areas especially in the winter, when social integration and activity are relatively low.

A Study of Post-processing Methods of Clustering Algorithm and Classification of the Segmented Regions (클러스터링 알고리즘의 후처리 방안과 분할된 영역들의 분류에 대한 연구)

  • Oh, Jun-Taek;Kim, Bo-Ram;Kim, Wook-Hyun
    • The KIPS Transactions:PartB
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    • v.16B no.1
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    • pp.7-16
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    • 2009
  • Some clustering algorithms have a problem that an image is over-segmented since both the spatial information between the segmented regions is not considered and the number of the clusters is defined in advance. Therefore, they are difficult to be applied to the applicable fields. This paper proposes the new post-processing methods, a reclassification of the inhomogeneous clusters and a region merging using Baysian algorithm, that improve the segmentation results of the clustering algorithms. The inhomogeneous cluster is firstly selected based on variance and between-class distance and it is then reclassified into the other clusters in the reclassification step. This reclassification is repeated until the optimal number determined by the minimum average within-class distance. And the similar regions are merged using Baysian algorithm based on Kullbeck-Leibler distance between the adjacent regions. So we can effectively solve the over-segmentation problem and the result can be applied to the applicable fields. Finally, we design a classification system for the segmented regions to validate the proposed method. The segmented regions are classified by SVM(Support Vector Machine) using the principal colors and the texture information of the segmented regions. In experiment, the proposed method showed the validity for various real-images and was effectively applied to the designed classification system.

Comparative analysis of linear model and deep learning algorithm for water usage prediction (물 사용량 예측을 위한 선형 모형과 딥러닝 알고리즘의 비교 분석)

  • Kim, Jongsung;Kim, DongHyun;Wang, Wonjoon;Lee, Haneul;Lee, Myungjin;Kim, Hung Soo
    • Journal of Korea Water Resources Association
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    • v.54 no.spc1
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    • pp.1083-1093
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    • 2021
  • It is an essential to predict water usage for establishing an optimal supply operation plan and reducing power consumption. However, the water usage by consumer has a non-linear characteristics due to various factors such as user type, usage pattern, and weather condition. Therefore, in order to predict the water consumption, we proposed the methodology linking various techniques that can consider non-linear characteristics of water use and we called it as KWD framework. Say, K-means (K) cluster analysis was performed to classify similar patterns according to usage of each individual consumer; then Wavelet (W) transform was applied to derive main periodic pattern of the usage by removing noise components; also, Deep (D) learning algorithm was used for trying to do learning of non-linear characteristics of water usage. The performance of a proposed framework or model was analyzed by comparing with the ARMA model, which is a linear time series model. As a result, the proposed model showed the correlation of 92% and ARMA model showed about 39%. Therefore, we had known that the performance of the proposed model was better than a linear time series model and KWD framework could be used for other nonlinear time series which has similar pattern with water usage. Therefore, if the KWD framework is used, it will be possible to accurately predict water usage and establish an optimal supply plan every the various event.

Variation in Fatty Acid Composition, Caffeic and Rosmarinic Acid Content, and Antioxidant Activity of Perilla Accessions (들깨 유전자원의 지방산 변이 및 rosmarinic acid와 caffeic acid의 함량에 따른 항산화 활성 비교)

  • Kim, Da Jeong;Assefa, Awraris Derbie;Jeong, Yi Jin;Jeon, Young Ah;Lee, Jae Eun;Lee, Myeong Chul;Lee, Ho Sun;Rhee, Ju Hee;Sung, Jung Sook
    • Korean Journal of Medicinal Crop Science
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    • v.27 no.2
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    • pp.96-107
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    • 2019
  • Background: The aim of this study was to compare the fatty acid composition, antioxidant activity, and the content of two major phenolic acids, caffeic and rosmarinic acids, of 45 Perilla accessions collected from Russia. Methods and Results: A total of 45 accessions of the genus Perilla were used in this study. The antioxidant activities of these accessions were analyzed using a spectrophotometer, and their caffeic and rosmarinic acid contents were determined using a reversed-phase ultraperformance liquid chromatography (UPLC) system. The Perilla seed oil was recovered using hexane in a soxhlet extraction method. The fatty acid compositions were analyzed using a Shimadzu QP2010 gas chromatography-mass spectoroscopy system. The results showed that accessions IT226732 and IT274300 had the highest content of caffeic and rosmarinic acid, respectively. A cluster analysis based on antioxidant assay results and concentration of phenolic acids led to the categorization of Perilla accessions into three major groups. The accessions in Group I were characterized by higher caffeic and rosmarinic acid content and antioxidant activity, compared to the accessions in the other two groups (p < 0.05). The total oil content ranged between 28.39 and 46.89%. The compositions of oleic, linoleic, and linolenic acid ranged from 11.83 to 19.55%, 11.92 to 16.71%, and 59.19 to 67.28%, respectively. Conclusions: The results of this study indicated that accessions IT274300, IT226732, IT274293, IT235818, and IT235820 could be used as a source of functional materials.