• Title/Summary/Keyword: CONDITION FACTOR(K)

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Revisiting Prediction Tools for Daylight Adequacy and Its Potential Improvement

  • Kim, Dong Hyun
    • KIEAE Journal
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    • v.17 no.3
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    • pp.35-44
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    • 2017
  • Purpose: This study questioned the efficiency of daylight factor as a daylight adequacy and investigated a method of how to complement its weakness by considering a direct sunlight component under a clear sky condition. Method: The Snowdon visitor centre cafe was chosen as a case study building and various techniques such as BRE formula, BRE sky protractor, Pilkington dot diagram and mock-upscale model under the artificial sky simulator were used to analyse and compare daylight factor values. An analysis of direct sunlight component under the clear sky condition was carried out by Climate Consultant 5.5, sun path diagram, and the artificial sky simulator. Result: The result of daylight factor analysis differed by the adopted techniques and it was also contradictory to the results on a direct sunlight penetration. The result not only showed the limitation of daylight factor as a metric but also suggested an improvement by combining it with direct sunlight analysis. The techniques used in this study had a merit of being applied in the early design stage and thus be beneficial to many design professions in order for early daylight performance analysis.

Correlation Analysis between Climate and Contamination Degree through Multiple Regression Analysis (다중회귀 분석을 통한 기후 및 오손도 간의 상관관계 분석)

  • Kim, Do-Young;Lee, Won-Young;Shim, Kyu-Il;Han, Sang-Ok;Park, Kang-Sik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05e
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    • pp.49-52
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    • 2003
  • The performance of insulators under contaminated conditions is the underlying and the most factor that determines insulation design for outdoor applications, Among the contamination factors, The sea salt is the most dangerous factor, and the salt factor have closed relation with climatic conditions, such as wind, temperature, humidity and so on, Effect of these factors to insulation system is different of each other, and need to show the correlation by multiple regression analysis techniques. In this paper, predicted and analyzed equivalent salt deposit density (ESDD) by change climatic condition through multiple regression analysis.

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High Power Factor High Efficiency PFC AC/DC Converter for LCD Monitor Adapter (LCD 모니터의 어댑터를 위한 고역률 고효율 PFC AC/DC 컨버터)

  • Park K. H.;Kim C. E.;Youn M. J.;Moon G. W.
    • Proceedings of the KIPE Conference
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    • 2003.11a
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    • pp.85-89
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    • 2003
  • Many single-stage PFC(power-facto.-correction) ACHC converters suffer from the high link voltage at high input voltage and light load condition. In this paper, to suppress the link voltage, a novel high power factor high efficiency PFC AC/DC converter is proposed using the single controller which generates two gate signals so that one of them is used far gate signal of the flyback DC/DC converter switch and the other is applied to the Boost PFC stage. A 130w prototype for LCD monitor adapter with universal input $(90-265V_{rms})$ and 19.5V 6.7A output is implemented to verify the operational principles and performances. The experimental results show that the maximum link voltage stress is about 450V at 270Vac input voltage. Moreover, efficiency and power factor are over $84\%$ and 0.95, respectively, under the full load condition.

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A study on the Physiological Character of living Space in Traditional Koaean House - Focsed on the rural house in Chonbuk province - (전통주거(傳統住居) 공간의 생리적(生理的) 특성(特性)에 관한 연구 - 전북지방 농촌주택(農村住宅)을 중심으로 -)

  • Kim, Yong-Jip
    • Journal of architectural history
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    • v.8 no.2 s.19
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    • pp.59-72
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    • 1999
  • The purpose of this study is to find the spatial factors, strucure of living and activity in traditional Korean house through the Phiysiological view, Spatial factors of the house are concerned to the interior environment and sanitary condition, The elements of respiratory, nerve, temperature sence. vision, hearing, smelling have good condition and touch, pressure sence, pain, metabolism are poor in the house, Ventilation, Lighting, pleasant condition of interior environment are concerned to the elements that mentioned above and have most important meaning in the relation rate of space as 1st factor. And 2nd factor is for metabolism, housework and rest, 3rd factor ie for temperature sence, privacy and reproduction. The relation rate of factors concering interior environment are high in the upper class house. Anbang has important meaning in the relation of living structure and relation sequence of space is anbang, Konnonbang, kitchen, toilet, water place, auxiliary buildings. The relation rate of activity is high in interior space in winter and exterior space in summer.

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Numerical Studies on Bearing Capacity Factor Nγ and Shape Factor of Strip and Circular Footings on Sand According to Dilatancy Angle (모래지반에서 팽창각에 따른 연속기초와 원형기초의 지지력계수 Nγ와 형상계수에 대한 수치해석 연구)

  • Kim, Dong-Joon;Youn, Jun-Ung;Jee, Sung-Hyun;Choi, Jaehyung;Lee, Jin-Sun;Kim, Dong-Soo
    • Journal of the Korean Geotechnical Society
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    • v.30 no.1
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    • pp.49-63
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    • 2014
  • Bearing capacity factor $N_{\gamma}$ and shape factor were studied for rigid strip and circular footings with a rough base on sand by numerical modelling considering the effect of dilation angle. The numerical model was developed with an explicit finite difference code. Loading procedures and interpretation methods were devised in order to shorten the running time while eliminating the exaggeration of the reaction caused by the explicit scheme. Using the Mohr-Coulomb plasticity model with associated (${\psi}={\phi}$) and nonassociated (${\psi}$ < ${\phi}$) flow-rules, the bearing capacity factor $N_{\gamma}$ was evaluated for various combinations of internal friction angles and dilation angles. Bearing capacity factor decreased as the dilation angle was reduced from the associated condition. An equation applicable to typical sands was proposed to evaluate the relative bearing capacity for the nonassociated condition compared to the associated condition on which most bearing capacity factor equations are based. The shape factor for the circular footing varied substantially when the plane-strain effect was taken into account for the strip footing. The numerical results of this study showed closer trends with the previous experimental results when the internal friction angle was increased for the strip footing. Discussions are made on the reason that previous equations for the shape factor give different results and recommendations are made for the appropriate design shape factor.

A Study to Define USLE P Factor from Field Survey in the Four Major Watersheds (현장조사를 통한 4대강 유역의 보전관리인자 산정 연구)

  • Yu, Nayoung;Shin, Minhwan;Seo, Jiyeon;Park, Youn Shik;Kim, Jonggun
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.2
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    • pp.37-44
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    • 2018
  • Universal soil loss equation (USLE) had been employed to estimate potential soil loss since it was developed from the statewide data measured and collected in the United States. The equation had an origin in average annual soil loss estimation though, it was modified or improved to provide better opportunities of soil loss estimation outside the United States. The equation has five factors, most studies modifying them to adapt regional status were focused on rainfall erosivity factor and cover management factor. While the conservation practice factor (USLE P factor) is to represent distinct features in agricultural fields, it is challenging to find studies regarding the factor improvements. Moreover, the factor is typically defined using slopes. The factor defining approach was suggested in the study, the approach is a step-by-step method allowing USLE P factor definition with given condition. The minimum condition is slope and field location to provide an opportunity for using in any GIS software and to reflect regionally distinct features. If watershed location, slope, crop type, and mulching type on furrows are given, detailed definition of the factors are possible. The approach was developed from field survey in South-Korea, it is expected to be used for potential soil loss using USLE in South-Korea.

TIGHT TOUGHNESS CONDITION FOR FRACTIONAL (g, f, n)-CRITICAL GRAPHS

  • Gao, Wei;Liang, Li;Xu, Tianwei;Zhou, Juxiang
    • Journal of the Korean Mathematical Society
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    • v.51 no.1
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    • pp.55-65
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    • 2014
  • A graph G is called a fractional (g, f, n)-critical graph if any n vertices are removed from G, then the resulting graph admits a fractional (g, f)-factor. In this paper, we determine the new toughness condition for fractional (g, f, n)-critical graphs. It is proved that G is fractional (g, f, n)-critical if $t(G){\geq}\frac{b^2-1+bn}{a}$. This bound is sharp in some sense. Furthermore, the best toughness condition for fractional (a, b, n)-critical graphs is given.

Water Quality Characteristics and Fish Community of the Gucheon Reservoir and Yeoncho Reservoir in Geoge Island

  • Han, Jeong-Ho;Paek, Woon-Kee;An, Kwang-Guk
    • Korean Journal of Environment and Ecology
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    • v.29 no.1
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    • pp.29-45
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    • 2015
  • Water chemistry and fish community, based on fish compositions and ecological characteristics(trophic/tolerance guilds and condition factor), were compared in Gucheon Reservoir($G_cR$) and Yeoncho Reservoir($Y_cR$). Chemical parameters of water quality such as BOD, COD, nutrient(N, P) and suspended solids indicated that water quality was better in the $Y_cR$ than $G_cR$, and the temporal variability in seasonal and interannual patterns were greater in the $Y_cR$. The greater variability was mainly attributed to intense dilutions of reservoir water by Asian monsoon rain during July-August. Fish guild analysis indicated that species diversity was higher in the $G_cR$ than the $Y_cR$, and that the proportion of tolerant and omnivore species were greater in the $Y_cR$. Regression analysis of body weight-total length showed that the regression coefficient(b value) was lower in the $G_cR$(2.15 ~ 2.40) than the $Y_cR$(2.59 ~ 3.14). Condition factor(K) of fish against the total length showed negative slope of Zacco temminckii, Carassius auratus, Pseudorasbora parva and Rhinogobius brunneus population in the $G_cR$, and a positive slope of Carassius auratus and Rhinogobius brunneus population in $Y_cR$. Overall, our data suggest that the growth of the fish populations, based on the length-weight relations and condition factor, reflected the trophic regime of nutrients and organic matter.

Ecological diagnosis of the Gongjicheon water system using length-weight relationship and condition factor(K) of population of the Zacco platypus (피라미 개체군의 length-weight relationship 및 condition factor(K)를 이용한 공지천수계의 생태적 진단)

  • Lee, Kwang-Yeol;Jang, Hara;Yun, Youngjin;Park, Seungchul;Kim, Joon Chul;Lee, Jaeyong;Choi, Jaeseok
    • Journal of Environmental Impact Assessment
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    • v.23 no.2
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    • pp.137-149
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    • 2014
  • The purpose of this study is to investigate the dynamics of the Zacco platypus population among streams in the Gongjicheon water system, Korea from December 2010 to October 2011. In this study, fish fauna was collected 27 Species belonged to 9 Families. The legal protection species, such as a natural monument and endangered species was not collected. Korean endemic species was collected 6 species including to Z. koreanus. The ratio of Korean endemic species was 22.6%, and it was lower than 51.3% that average of Korean endemic species in the Hangang water system. About these status, we considered that Gongjicheon water system had lost of the unique characteristics of the Hangang water system by the anthropogenic disturbances. The result of analysis to length-weight relationship and condition factor(K) of Z. platypus population in the Gongjicheon water system, the regression coefficient value(b) to indication of growth degree of the population was 3.04 and the slope of the condition factor(K) to indication of corpulency had positive value, respectively. These results seems to be that the Z. platypus population is maintained to a little unstably. In addition, the values of the degree of growth and corpulence were very low than the other natural streams in the Hangang water system, so it considered that the many artificially stress factors are occurred in this study area. These results are similar to Fish Assessment Index(FAI) in the assessment for health of aquatic ecosystem. Therefore, we are considered to require precise investigation and sustained monitoring for the restorations of stream ecosystem in the Gongjicheon water system.

A Study on improving the competitiveness of agri-food export sector in Korea - with Porter's Diamond Model - (우리나라 농식품 수출부문의 경쟁력 향상방안 연구 - 포터의 다이아몬드 모델을 중심으로 -)

  • Cho, Sung-Je;Park, Hyun-Hee
    • International Commerce and Information Review
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    • v.13 no.3
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    • pp.249-274
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    • 2011
  • This paper examines agri-food export competitiveness among 4 countries(Korea, USA, Japan, China) based on Porter's Diamond model approach. Korea agri-food competitiveness index is much less than those of other countries. Korea is the lowest ranked among the 4 countries in terms of three determinants(except 1 factor, related and supporting industries) of Porter's Diamond Model: Factor condition, demand condition, firm strategy, structure and rivalry. Korea is assumed to have weak point in the factor condition, demand condition because of low capital and land as well as insufficient investment on the agri-food sector. on the other hand, it seems to have strong factor in consumer condition(demand condition). This paper suggest the following strategies to reinforced the agri-food export sector in Korea. 1) an incentive system for seed development and capital investment, 2) a cluster strategy between agriculture and related industry.

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