• Title/Summary/Keyword: physical characteristic

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A study on Device Driver for RTOS-FT System (RTOS-FT 시스템의 디바이스 드라이버에 관한 연구)

  • 권용진;신덕호;유광균;이기서
    • Proceedings of the KSR Conference
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    • 2002.05a
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    • pp.461-466
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    • 2002
  • This paper show Device Driver for RTOS-FT Systems. In this paper, a definition of Device Driver is introduced which is used in RTOS-FT Systems. The structure of Device Driver is briefly divided into physical layer and logical layer. The specific characteristic of Physical Held and logical field which is discussed in this paper is suggested for the system which is satisfied with fault-tolerant theory.

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Correlation-Analysis between Characteristic Factors of Watersheds and Peak flows in the Irrigation Reservoirs (농업용(農業用) 저수지(貯水池)의 유역(流域) 특성인자(特性因子)와 첨두유량(尖頭流量)과의 상관분석(相關分析))

  • Suh, Seung Duk;Song, Yi Ho;Kim, Hoal Gon
    • Current Research on Agriculture and Life Sciences
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    • v.10
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    • pp.35-40
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    • 1992
  • The purpose of this study is to develop regression equations between peak flow and physical characteristic factors of watersheds. 112 irrigation reservoirs located in South Korea which are equal or larger than 200 has. in the irrigation area, are used in the analysis of this study. The results obtained from this study are as follows. 1. The results of correlation analysis of the relationships among the characteristic factors of the watersheds have been derived high significances. 2. Relationship between the peak flow and the simple correlation analysis of physical characteristic factors of the watersheds has been derived low significance. 3. The result of the multiple regression analysis between the peak flow and four physical characteristic factors of watershed such as watershed area, main stream length, average slope of main stream and elevation of reservoir are shown as the equation ; $Q_{100}=66.43A^{0.869}L^{-0.536}S^{0.456}Hs^{-0.122}$.(r=0.838)

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Identification of Structural Characteristic Matrices of Steel Bar by Genetic Algorithm (유전알고리즘에 의한 강봉의 구조특성행렬 산출법)

  • Park, S.C.;Je, H.K.;Yi, G.J.;Park, Y.B.;Park, K.I.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.10
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    • pp.946-952
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    • 2010
  • A method for the identification of structural characteristic parameters of a steel bar in the matrices form such as stiffness matrices and mass matrices from frequency response function(FRF) by genetic algorithm is proposed. As the method is based on the finite element method(FEM), the obtained matrices have perfect physical meanings if the FRFs got from the analysis and the FRFs from the experiments were well coincident each other. The identified characteristic matrices from the FRFs with maximun 40 % of random errors by the genetic algorithm are coincident with the characteristic matrices from exact FEM FRFs well each other. The fitted element diameters by using only 2 points experimental FRFs are similar to the actual diameters of the bar. The fitted FRFs are good accordance with the experimental FRFs on the graphs. FRFs of the rest 9 points not used for calculating could be fitted even well.

Bridge-edges Mining in Complex Power Optical Cable Network based on Minimum Connected Chain Attenuation Topological Potential

  • Jiang, Wanchang;Liu, Yanhui;Wang, Shengda;Guo, Jian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.1030-1050
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    • 2021
  • The edges with "bridge characteristic" play the role of connecting the communication between regions in power optical cable network. To solve the problem of mining edges with "bridge characteristic" in provincial power optical cable network, the complex power optical cable network model is constructed. Firstly, to measure the generated potential energy of all nodes in n-level neighborhood local structure for one edge, the n-level neighborhood local structure topological potential is designed. And the minimum connected chain attenuation is designed to measure the attenuation degree caused by substituted edges. On the basis of that, the minimum connected chain attenuation topological potential based measurement is designed. By using the designed measurement, a bridge-edges mining algorithm is proposed to mine edges with "bridge characteristic". The experiments are conducted on the physical topology of the power optical cable network in Jilin Province. Compared with that of other three typical methods, the network efficiency and connectivity of the proposed method are decreased by 3.58% and 28.79% on average respectively. And the proposed method can not only mine optical cable connection with typical "bridge characteristic" but also can mine optical cables without obvious characteristics of city or voltage, but it have "bridge characteristic" in the topology structure.

Subjective Evaluation of Wear Comfort and Related Physical Variables under Warm and Humid Condition (고온 다습한 환경에서의 주관적 착용 쾌적감과 관련 물성 변인)

  • Kim, Jeong-Hwa;Hong, Gyeong-Hui;Jo, Seung-Sik
    • Journal of the Korean Society of Clothing and Textiles
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    • v.21 no.6
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    • pp.1021-1030
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    • 1997
  • Physical variables related to the subjective evaluation of wear comfort were explored. Experimental fabrics was those used in the previous paper where subjective sensations of women's thin shirts were reported. Fabrics include 100% cotton (unfinished), 100% cotton (water repellent finished), cotton/polyester 35/65 (unfinished), cotton/polyester 35/65 (peach skin finished), 100% polyester fabric(plain), 100% polyester crepe. Among various physical properties of the experimental fabrics, heat 8E moisture transport properties and surface properties were chosen as important variables based on the regression coefficient. Especially, humidity at the microclimate in dynamic mode was highly correlated to the subjective evaluation and appeared to be a sensitive physical predictor, compared to dry thermal transmission rate or water vapor transmission rate. Surface characteristic parameters, however, did not show consistant trend in the prediction of the human's subjective sensation. Interaction between surface properties and humidity measurement was also observed.

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Control of Cyber-Physical Systems Under Cyber-Attacks (사이버공격에 강인한 사이버물리시스템의 제어)

  • Lee, Tae H.
    • IEMEK Journal of Embedded Systems and Applications
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    • v.14 no.5
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    • pp.269-275
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    • 2019
  • This paper addresses the control problem of cyber-physical systems under controller attack. A novel discontinuous Lyapunov functionals are employed to fully utilize sampled-data pattern which characteristic is commonly appeared in cyber-physical systems. By considering the limited resource of networks, cyber-attacks on the controller are considered randomly occurring and are described as an attack function which is nonlinear but assumed to be satisfying Lipschitz condition. Novel criteria for designing controller with robustness for cyber-attacks are developed in terms of linear matrix inequality (LMI). Finally, a numerical example is given to prove the usefulness of the proposed method.

Risk Factors for Sarcopenia, Sarcopenic Obesity, and Sarcopenia Without Obesity in Older Adults

  • Kim, Seo-hyun;Yi, Chung-hwi;Lim, Jin-seok
    • Physical Therapy Korea
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    • v.28 no.3
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    • pp.177-185
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    • 2021
  • Background: Muscle undergoes change continuously with aging. Sarcopenia, in which muscle mass decrease with aging, is associated with various diseases, the risk of falling, and the deterioration of quality of life. Obesity and sarcopenia also have a synergy effect on the disease of the older adults. Objects: This study examined the risk factors for sarcopenia, sarcopenic obesity, and sarcopenia without obesity and developed prediction models. Methods: This machine-learning study used the 2008-2011 Korea National Health and Nutrition Examination Surveys in the analysis. After data curation, 5,563 older participants were selected, of whom 1,169 had sarcopenia, 538 had sarcopenic obesity, and 631 had sarcopenia without obesity; the remaining 4,394 were normal. Decision tree and random forest models were used to identify risk factors. Results: The risk factors for sarcopenia chosen by both methods were body mass index (BMI) and duration of moderate physical activity; those for sarcopenic obesity were sex, BMI, and duration of moderate physical activity; and those for sarcopenia without obesity were BMI and sex. The areas under the receiver operating characteristic curves of all prediction models exceeded 0.75. BMI could predict sarcopenia-related disease. Conclusion: Risk factors for sarcopenia-related diseases should be identified and programs for sarcopenia-related disease prevention should be developed. Data-mining research using population data should be conducted to enhance the effectiveness of early treatment for people with sarcopenia-related diseases through predictive models.

Factors Affecting Visual Satisfaction of Benches at Urban Park (도시공원에서 벤치의 시각적 만족도에 영향을 미치는 요인)

  • 유상완;권상준;정정섭
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.3
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    • pp.88-96
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    • 2000
  • The objective of this study is to evaluate the preference and visual characteristic of users according to the location of benches at urban community parks. The types of benches are separated into four patterns and located in four representative places at urban community parks. Each relations between visual preference and adjective related factors are calibrated by the estimated results of Pearson correlation coefficient. Moreover, the factors which affect the visual preference are obtained by multiple regression analysis and to calibrate the each factors significant level, the method of multivariate variance analysis is applied. The results of this study are summzrized as belows: 1. Four types of factors which consist the visual characteristic are classified as emotional factor of visual images(aesthetic factor(F1), texture related factor(F2)) and physical factor(physical factor(F3), transformable factor(F4)). Each factor's eigenvalue is appears as 5.27∼1.78 and the eigenvalue of emotional factor of visual images is more higher than the physical factor. 2. The correlation coefficient between visual preference according to the location of benches(X21) and aesthetic factor(f1) is estimated as 0.79, which is highest value among the four factors. And the correlation coefficient of texture related factor(f2), physical factor(F3) and transformable factor(F4) is estimated as 0.14, 0.04 and 0.08 respectively. 3. The visual preference of users according to the location of benches is greatly affected by the emotional factor of visual images(F1, F2) and the physical factor(F3, F4) are poorly related. The results of this study suggest the effective guidelines for the location of leisure facilities. Moreover the design and planning of leisure facilities at the urban community park have to be reexamined. What must be examined from now on is as follows: First, the preference research of rest facilities in the urban park through the multiple approach must be carried out continuously. Second, the research about the visual quality of the environmental sight observed in sitting on the bench as well as the visual quality of the showed object and place needs to be supported. Nevertheless, through this study the utilization into the useful data of the plan and the design for the systematic disposition of landscape architecture equipments centered on the users can be expected.

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The Estimation of the Extent of Weathering using Fractal Dimension through a Comparison with Chemical Characteristic (화학적 특성과의 비교 분석을 통한 프랙탈 차원을 이용한 풍화도 추정)

  • Noh, Soo-Kack;Son, Young-Hwan;Bong, Tae-Ho;Park, Jae-Sung
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.2
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    • pp.127-135
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    • 2012
  • The processes of chemical and physical weathering occur simultaneously. The objective of this study was to estimate the degree weathered using fractal dimension through comparison with chemical characteristic of soil samples from Pohang (PH) and Kimpo (KP). Comparing chemical characteristics with fractal dimension, $SiO_2$, $Na_2O$, $K_2O$ content decreased and loss of ignition increased as fractal dimension increased. And fractal dimension showed high correlation with CWI while ATI, STI CIW, PI, CIA and RR demonstrated different degrees of correlation with fractal dimension. The tendency of the changes in oxide content and chemical weathering index with increasing fractal dimension appeared to be similar with the chemical changes due to weathering. Therefore, fractal dimension could be a good indicator representing the extent of weathering and chemical changes.

Strength characteristic transformation of weathered soil caused by freezing-thawing (동결 -융해에 따른 풍화토의 강도특성 변화)

  • 김수삼;박영목;정승용;김용수
    • Proceedings of the KSR Conference
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    • 2001.10a
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    • pp.520-525
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    • 2001
  • It's strongly recommended to check upon the slope stability of soil nearby railroad, since the freezing-thawing repeat in long term may cause decrease of slope stability. The study is, therefore, focused on the strength characteristic transformation of soil, measuring it experimentally, throughout physical and mechanical tests operated by the freezing-thawing repeat tests. The sampling of weathered soil used for the embankment materials along the domestic railway lines are classified by parent-rock, and then collected after it in the first hand. It tells that Uniaxial strength and axial strain were decreased simultaneously as the frequency of freezing-thawing repeat increased and its range was reduced into 25~85 percentage off comparing to uniaxial strength of unfreezing-soils when about 100 times of freezing-thawing repeats occurred. Following the result of direct shear tests, the cohesion of freezing-soil with freezing-thawing repeats shows 11∼60 percentage less than that of unfreezing-soil but the change of internal friction angle of the soil is extremely slight, enough to ignore. As a result. it could be found that strength characteristic transformation has highly correlated with freezing-thawing repeat.

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