• Title/Summary/Keyword: Rational

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Assessing the Performance of CMIP5 GCMs for Various Climatic Elements and Indicators over the Southeast US (다양한 기후요소와 지표에 대한 CMIP5 GCMs 모델 성능 평가 -미국 남동부 지역을 대상으로-)

  • Hwang, Syewoon
    • Journal of Korea Water Resources Association
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    • v.47 no.11
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    • pp.1039-1050
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    • 2014
  • The goal of this study is to demonstrate the diversity of model performance for various climatic elements and indicators. We evaluated the skills of the most advanced 17 General Circulation Models (GCMs) i.e., CMIP5 (Climate Model Inter-comparison project, phase 5) climate models in reproducing retrospective climatology from 1950 to 2000 over the Southeast US for the key climatic elements important in the hydrological and agricultural perspectives (i.e., precipitation, maximum and minimum temperature, and wind speed). The biases of raw CMIP5 GCMs were estimated for 16 different climatic indicators that imply mean climatology, temporal variability, extreme frequency, etc. using a grid-based observational dataset as reference. Based on the error (RMSE) and correlation (R) of GCM outputs, the error-based GCM ranks were assigned on average over the indicators. Overall, the GCMs showed much better accuracy in representing mean climatology of temperature comparing to other elements whereas few GCM showed acceptable skills for precipitation. It was also found that the model skills and ranks would be substantially different by the climatic elements, error statistics applied for evaluation, and indicators as well. This study presents significance of GCM uncertainty and the needs of considering rational strategies for climate model evaluation and selection.

Relative RPCs Bias-compensation for Satellite Stereo Images Processing (고해상도 입체 위성영상 처리를 위한 무기준점 기반 상호표정)

  • Oh, Jae Hong;Lee, Chang No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.4
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    • pp.287-293
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    • 2018
  • It is prerequisite to generate epipolar resampled images by reducing the y-parallax for accurate and efficient processing of satellite stereo images. Minimizing y-parallax requires the accurate sensor modeling that is carried out with ground control points. However, the approach is not feasible over inaccessible areas where control points cannot be easily acquired. For the case, a relative orientation can be utilized only with conjugate points, but its accuracy for satellite sensor should be studied because the sensor has different geometry compared to well-known frame type cameras. Therefore, we carried out the bias-compensation of RPCs (Rational Polynomial Coefficients) without any ground control points to study its precision and effects on the y-parallax in epipolar resampled images. The conjugate points were generated with stereo image matching with outlier removals. RPCs compensation was performed based on the affine and polynomial models. We analyzed the reprojection error of the compensated RPCs and the y-parallax in the resampled images. Experimental result showed one-pixel level of y-parallax for Kompsat-3 stereo data.

Factors Required to Sustain Pastoral Farming Systems and Forage Supply In Winter-Cold Zones in Korea (한국의 동계한냉지역에 있어서 초지개발과 조사료 공급의 활성화에 필요한 요인)

  • 김동암
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.3
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    • pp.30-40
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    • 1992
  • The area of grassland established and the arable land in forage production have been decreased recently in Korea. As a result, forages available from the grassland and the arable land provided only 40% of the total roughage consumed by cattle in 1991, compared with 54% in 1989. The decreasing trend of the forage production has been impinged on by a number of legislative. socio-economic. technical and other constraints negatively affecting grassland and forage development. Consequently. effective systems and strategies are quite necessary to have sustainable grassland farming in Korea. In spring and autumn, temperatures are too low for subtropical forage crops, and the summer monsoon climate is another serious limitation to the use of cool-season species. Therefore it is an imperative that not only the research-based grassland development but also the forage crop production should be strongly supported by the government authorities to overcome such climatic limitations. Private forest land holdings are of relatively small units in Korea. Accordingly. it is necessary and important to enlarge the forest land holdings per farm to develop as economic units of grassland. For this the government should introduce new policy measures such as for example: long-term leases of Sorest land and the idle arable land of absentee owners ; rational rental system of national and public forest lands; integrating livestock and forest production. All the laws and regulations standing in the way of the grassland development in forest lands should be modified and revised to open the way for much easier development of grassland. It is also proposed that a high level of financial incentives -hould be provided for structural improvements for the grassland development. They may be: mechanization facilitation, construction of new roads relating to grassland, and land exchange and consolidation. And it is basically necessary that financial enumeration or profits must be garanteed in order to motivate farmers to keep up farming continuously. For more efficient grassland development in mountainous areas, reorganization of Alpine Experiment Station and NAB1 Namwon Branch Station may be needed. Research should be strengthened for completion of pasture mixtures, development of maximum forage production methods with a view to saving labor and reducing production costs, introduction of grazing and forage conservation techniques. and utilization of rice straw as more palatable and nutritious forage source. In order to have more efficient and effective transfer of advanced forage production technologies to livestock farmers the user-clients. it is also essential that special training measures should be given to livestock farmers through making greater use of specialized research and extension workers.

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Molecular Typing of Salmonella enterica serovar Typhi Strains Isolated in Busan by Pulsed-Field Gel Electrophoresis (부산지역에서 분리된 Salmonella enterica serovar Typhi균에 대한 PFGE를 이용한 Molecular typing)

  • Min, Sang-Kee;Lee, Ju-Hyun;Park, Eun-Hee;Kim, Jung-Ah;Kim, Kyu-Won
    • Journal of Life Science
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    • v.16 no.4
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    • pp.664-671
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    • 2006
  • We obtained 424 Salmonella enterica serovar Typhi isolates from sporadic cases of infection in Busan during 1996 to 2005. We investigated the trend of antimicrobial resistance and molecular typing by pulsed-field gel electrophoresis (PFGE). Of the total 424 isolates, 6 strains (1.4%) were multidrug-resistant (MDR) S. enterica serovar Typhi isolates, 2 strains (0.5%) were resistant to only nalidixic acid, and the remaining 416 strains (98.1%) were fully susceptible to the 18 antimicrobial agent. PFGE of XbaI-digested chromosomal DNA was performed on 50 sporadic S. enterica serovar Typhi isolates with the objective of investigating the extent of genetic diversity of these isolates in our region. We could find that these isolates were much more heterogeneous and at least 32 different PFGE patterns were generated according by dice coefficient, between 0.69 and 1.0. Restriction fragment patterns consisted of 13 to 18 fragments ranged in size from 20 to 630 kb. The results confirmed that PFGE would be an useful tool for investigating surveillance of sporadic or outbreak case and assessing clonality for S. enterica serovar Typhi in Busan area. Our finding will be valuable in developing rational strategies to control this pathogen and setting the basis of an effective PulseNet system in Korea.

The effects of perceived father's rearing attitude on leisure satisfaction and leisure constraint in middle school students: the mediating effects of self-efficacy (중학생이 지각한 아버지의 애정-합리적 설명형 양육태도가 여가만족 및 여가제약에 미치는 영향 : 자기효능감의 매개효과를 중심으로)

  • Jung, In-Kyung;Kim, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.27 no.2
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    • pp.77-93
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    • 2015
  • The purpose of this study was to investigate the mediating effects of self-efficacy on the relationship between perceived father's rearing attitude and leisure satisfaction/leisure constraint in junior high school students. A survey was conducted using a convenient sample drawn from 448 students from eleven junior high school in Seoul area. Data were analyzed using SPSS 20.0 program. The results showed that students who perceived their father's rearing attitude as affection-rational explanation performed more of out-door leisure activity with their family. Perceived father's rearing attitude and self-efficacy was positively related with leisure satisfaction but negatively related with leisure constraint. In addition, self-efficacy partially mediated the relationship between perceived father's rearing attitude and leisure satisfaction/leisure constraint. These results suggest the leisure activity could be increased by father's rearing attitude through improving self-efficacy. Therefore, to improve the leisure activity through increase of leisure satisfaction and decrease of leisure constraint, father should raise their children in love and help to grow their self-efficacy.

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A Seismatic Performance Analysis of Circular RC Bridge Piers I. Evaluation of Influence Parameters of Confinement Steel Ratio (원형 철근콘크리트 교각의 내진성능 I. 심부구속철근비 영향 변수 평가)

  • Lee Dae-Hyoung;Park Chang-Kyu;Kim Hyun-Jun;Chung Young-Soo
    • Journal of the Korea Concrete Institute
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    • v.17 no.4 s.88
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    • pp.603-611
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    • 2005
  • For the establishment of rational seismic design code for RC (reinforced concrete) bridge pier, this paper has analyzed the seismic code of RC bridge pier specified in )veil-known codes such as KHBDS (Korea Highway Bridge Design Specification), AASHTO Standard, ATC-32, Eurocode 8, NZS 3101, etc. So as to secure aseismic ductility of RC pier, transverse confinement steel ratios of those codes have been examined together with other design parameters such as strength of concrete and reinforcing steel, axial force ratio, aspect ratio, longitudinal steel ratio, etc. However, there has been arisen a doubt for the validity of those parameters. Thus, the objective of this study is to quantitatively evaluate the validity of design parameter of each code on the experimental seismic ductility for about 80 test specimens. It was concluded from this study that the axial force ratio is a dominant factor for the seismic displacement ductility. Therefore, it Is desirable that the axial force ratio be further taken into account in the corresponding seismic design formula of RC bridge pier in current KHBDS.

A Study on the Research Performance and Efficiency of Convergence Research Projects sponsored by National Research Council of Science & Technology : A Comparative Study of Convergence Research and General Trust Projects Using DEA (국가과학기술연구회 융합연구사업의 연구성과 효율성에 관한 연구 : DEA를 활용한 융합연구 및 일반수탁사업의 비교분석을 중심으로)

  • Yuk, Hyounggab;Kang, Jaeyeol;Pae, Kibong;Kang, Daeseok
    • Journal of the Korea Convergence Society
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    • v.11 no.3
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    • pp.211-218
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    • 2020
  • This study compared and analyzed the efficiency of the research results of the convergence research project operated by the National Science and Technology Research Council and the general research project carried out by the Government-funded research institute and proposed measures to enhance the efficiency of the operation and management of convergence research. Research data were collected from 21 government-funded research institutes through an information disclosure claim and DEA analysis was conducted for efficiency assessment. The SCI papers of convergence research showed high efficiency, and the patent registration and technology transfer sector showed high efficiency of general research projects. This indicates that convergence research projects for securing lead and original technologies are highly efficient, but their performance is low due to lack of participation by businesses in terms of the utilization of derived technologies, and more companies' participation and opportunities are needed for practical use of convergence research results. Through the analysis of efficiency of convergence research project performance, this study provided policy and guidance for R&D planning for rational investment of limited manpower and research costs. Further, future research on identifying efficiency is proposed depending on the type of technology subject to convergence research as a method for managing convergence research.

Learning for Environment and Behavior Pattern Using Recurrent Modular Neural Network Based on Estimated Emotion (감정평가에 기반한 환경과 행동패턴 학습을 위한 궤환 모듈라 네트워크)

  • Kim, Seong-Joo;Choi, Woo-Kyung;Kim, Yong-Min;Jeon, Hong-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.1
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    • pp.9-14
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    • 2004
  • Rational sense is affected by emotion. If we add the factor of estimated emotion by environment information into robots, we may get more intelligent and human-friendly robots. However, various sensory information and pattern classification are prescribed for robots to learn emotion so that the networks are suitable for the necessity of robots. Neural network has superior ability to extract character of system but neural network has defect of temporal cross talk and local minimum convergence. To solve the defects, many kinds of modular neural networks have been proposed because they divide a complex problem into simple several subproblems. The modular neural network, introduced by Jacobs and Jordan, shows an excellent ability of recomposition and recombination of complex work. On the other hand, the recurrent network acquires state representations and representations of state make the recurrent neural network suitable for diverse applications such as nonlinear prediction and modeling. In this paper, we applied recurrent network for the expert network in the modular neural network structure to learn data pattern based on emotional assessment. To show the performance of the proposed network, simulation of learning the environment and behavior pattern is proceeded with the real time implementation. The given problem is very complex and has too many cases to learn. The result will show the performance and good ability of the proposed network and will be compared with the result of other method, general modular neural network.

A Study on Reconstruction and Remodeling's Selection Factors of Old Apartment Houses Using AHP (AHP를 활용한 노후 공동주택의 재건축과 리모델링의 사업선택결정에 관한 연구)

  • Son, Sung-Hyun;You, Seung-Min;Lee, Ki-Seok;Choi, Yoon-Ki
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.6
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    • pp.12-21
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    • 2015
  • Reconstruction and remodeling have been introduced as a part of renewal (redevelopment) projects for old apartments built after the mid-1970's and government policies for revitalizing each project has been changed continually. However, the frequent changes of the policies have caused conflicts among business entities in selecting business methods. The conflicts from their early stages have made serious problems in the entire business process. Therefore, this study deduced factors of business selection by applying comparison analysis between the two business projects on how certain factors have an influence on selecting reconstruction and remodeling business projects. Based on the analysis, four categories and 26 factors were finally selected. After then, the priority of each selection factor was deduced through the AHP method used for analysis of relative importance and impact values regarding to the business selection. It is expected to resolve conflicts among owners and select rational directions for reconstruction and remodeling business, based on the conclusion through analysis of influence on selection factors.

Design and evaluation of a VPRS-based misbehavior detection scheme for VANETs (차량애드혹망을 위한 가변정밀도 러프집합 기반 부정행위 탐지 방법의 설계 및 평가)

  • Kim, Chil-Hwa;Bae, Ihn-Han
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.6
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    • pp.1153-1166
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    • 2011
  • Detecting misbehavior in vehicular ad-hoc networks is very important problem with wide range of implications including safety related and congestion avoidance applications. Most misbehavior detection schemes are concerned with detection of malicious nodes. In most situations, vehicles would send wrong information because of selfish reasons of their owners. Because of rational behavior, it is more important to detect false information than to identify misbehaving nodes. In this paper, we propose the variable precision rough sets based misbehavior detection scheme which detects false alert message and misbehaving nodes by observing their action after sending out the alert messages. In the proposed scheme, the alert information system, alert profile is constructed from valid actions of moving nodes in vehicular ad-hoc networks. Once a moving vehicle receives an alert message from another vehicle, it finds out the alert type from the alert message. When the vehicle later receives a beacon from alert raised vehicle after an elapse of time, then it computes the relative classification error by using variable precision rough sets from the alert information system. If the relative classification error is lager than the maximum allowable relative classification error of the alert type, the vehicle decides the message as false alert message. Th performance of the proposed scheme is evaluated as two metrics: correct ratio and incorrect ratio through a simulation.