• Title/Summary/Keyword: Climatic factor

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Unsaturated Soil Mechanics for Slope Stability

  • Rahardjo, Harianto;Satyanaga, Alfrendo;Leong, Eng-Choon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2007.09a
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    • pp.481-501
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    • 2007
  • Excessive rainfalls due to climatic changes can trigger an increase in rainfall-induced slope failures that pose real threats to both lives and properties. Many high slopes in residual soils could stand at a steep angle, but failed during or after rainfall. Commonly, these slopes have a deep groundwater table and negative pore-water pressures in the unsaturated zone above the groundwater table contribute to the shear strength of soil and consequently to factor of safety of the slope. Stability assessment of slope under rainfall requires information on rate of rainwater infiltration in the unsaturated zone and the resulting changes in pore-water pressure and shear strength of soil. This paper describes the application of unsaturated soil mechanics principles and theories in the assessment of rainfall effect on stability of slope through proper characterization of soil properties, measurement of negative pore-water pressures, seepage and slope stability analyses involving unsaturated and saturated soils. Factors controlling the rate of changes in factor of safety during rainfall and a preventive method to minimize infiltration are highlighted in this paper.

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Population Dynamics of Mustard Aphid, Lipaphis erysimi (Kaltenbach) as Influenced by Abiotic Factors and Different Rapeseed Mustard Genotypes

  • Roy, Santosh-Kumar;Kanchan Baral
    • International Journal of Industrial Entomology and Biomaterials
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    • v.4 no.1
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    • pp.69-76
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    • 2002
  • Mustard aphid, Lipaphis erysimi(Kalt.) plays a key role in determining the productivity of rapeseed-mustard. This pest alone attributes 30-70% losses in yield potential in different agro climatic zones with a mean loss of 54.2% in India. Considering the extent of damage caused by the pest, the present experiment was conducted at Pulses and Oilseeds Research Station during 1992-93 to 1994-95 to study the migratory nature of mustard aphid by trapping them in yellow colour pan tray and their simultaneous growth and development on three different genotypes. The temperature during noon hours is the predominant factor to govern the appearance of alate mustard aphid in rapeseed-mustard field. Stepwise regression analysis revealed that temperature and relative humidity played an important role for its development. The variety RW white flower glossy stem harboured minimum number of aphid in comparison to other two varieties B 9 and T6342. The population reached a peak of 61.28 aphids/10 cm central twig during $6^{th}$ standard week irrespective of varieties.

Climatic classification of Korea by factor analysis (인자분석에 의한 한국의 기후구분)

  • ;Kim, Yong-Mahn
    • Journal of the Korean Geographical Society
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    • v.41
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    • pp.49-56
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    • 1990
  • 본 연구는 한반도 전체의 2207 Mesh에 입력된 기온과 강수량의 6개요소를 데이터로 하여 인자분석하고 그 결과를 군화분석하여 한반도의 기후구분을 시도한 것이다. 결과로 나타난 기후구는 기발표된 여러 기후구와 유사성이 많아, 데이터로 택한 변수가 연평균 기온, 최난월 및 최한월 기온, 전년강수량, 여름 및 겨울 강수량 등 6개에 불과했음에도 불구하고 한반도의 기후의 특징이 잘 나타난 지리구라고 판단된다. 이것은 우리나라의 기후가 기온과 강수량, 특히 그 연평균치 및 계절적 집중도에 의하여 크게 지배되고 있음을 다시 한번 입증시켜 주는 것이라 생각된다. 그러나 뚜렷한 기후 특성을 지니고 있는 울릉도가 하나의 기후구로 나타나지 않는것은 적설량이나, 연간 강수일수 등 울릉도의 기후 특성을 나타낼 수 있는 변수가 입력되지 않았고, 울릉도의 기후현상이 나타날 정도로 기후구가 세분화되지 않은데 있는것으로 짐작된다. 본 연구에서 제시한 8개 기후구를 교과서용 기후구분의 12개 기후구와 비교해 보면, 북부내륙과 북부동안 기후구가 거의 같은 것을 비롯하여 여러면에서 공통성을 발견할 수 있다. 그러나 교과서용 구분의 내륙형과 해안형, 특해 서안형과 의 구분은 본 연구의 기후구와 비교할 때 지나치게 도식화한 느낌이 든다.

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Performance Analysis of Grid-Connected PCS for PV System by Field Demonstration Test

  • So J.H.;Jung Y.S.;Yu G.J.;Jung M.W.;Kang G.H.;Choi J.Y.
    • Proceedings of the KIPE Conference
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    • 2003.07b
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    • pp.516-519
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    • 2003
  • 3kW photovoltaic (PV) systems and data acquisition system are constructed for performance analysis of PV system at field demonstration test center (FDTC) of Korea. As climatic and irradiation conditions are varied, the performance characteristics of PV system are collected and analyzed in data acquisition system. From these results, the performances of gird-connected power conditioning system (PCS) fur PV system have been evaluated and analyzed. Furthermore, performance indices of grid-connected PCS e.g. output power, efficiency, loss factor, and the other index at the site are reviewed.

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Performance Analysis of 3kW Grid-Connected PV System (3kW급 계통연계형 태양광발전시스템의 성능 비교분석)

  • So J.H.;Jung Y.S.;Yu G.J.;Lee K.O.;Choi J.Y.;Ahn H.S
    • Proceedings of the KIPE Conference
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    • 2003.07b
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    • pp.707-710
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    • 2003
  • 3kW grid-connected photovoltaic (PV) system and data acquisition system are constructed for performance analysis of PV system at field demonstration test center of Gwang-Ju in Korea. As climatic and irradiation conditions are varied, operation characteristics of the PV system are collected and analyzed in data acquisition system. From these results, the performances of PV system have simulated and evaluated using simulation tool in comparison with actual value of data acquisition system of field demonstration test center. Furthermore, performance of total PV system e.g. electric power and loss factor at the site are reviewed.

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Analyses and Evaluation of Gird Connected PCU for PV System (태양광발전용 계통연계형 PCU의 성능특성 분석평가)

  • So J. H.;Jung Y. S.;Yu G. J.;Choi J. Y.
    • Proceedings of the KIPE Conference
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    • 2003.11a
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    • pp.65-68
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    • 2003
  • 3kW grid-connected photovoltaic(PV) systems and data acquisition system are constructed for performance analysis of PV system at field demonstration test center of Gwang-Ju in Korea. As climatic and irradiation conditions are varied, operation characteristics of the PV system are collected and analyzed in data acquisition system. From these results, the performances of PV systems have simulated and evaluated using simulation tool In comparison with actual value of data acquisition system of field demonstration test center. Furthermore, performance of each PV system e.g. electric power and loss factor is reviewed.

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The Distribution Characteristics of Salt Contaminants with Statistical Method in East Coast (통계적 처리방법을 이용한 동해안 염해 오손물의 분포특성)

  • Choi, Nam-Ho;Park, Kang-Sik;Han, Sang-Ok
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.3
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    • pp.130-135
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    • 2001
  • In this paper, the distribution characteristics of salt contaminants with the distance from sea in East coast, from Sokcho to Pusan of Korea peninsula were investigated to evaluate the design standard of KEPCO. To get the equivalent salt deposit density(ESDD), conventional brush wiping method was used. As the measuring period is comparatively short, and the measuring interval is long to check the maximum value, acquired ESDD data is very lower than the recommended value in the standard. The measured data didn't follow normal distribution, so it should take the statistical treatment. Through normalizing method, we could get a reliable probability data. In the past investigation, the accumulation characteristics of Japan is consulted to set the criterion, but the climatic condition of Korea is different to Japan. With the comparison of precipitation data and some measured data for long tern accumulation, we could set appropriate accumulation factor.

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A Study of Bolt Tightening Changing Factor according to Durability Degradation (내구 열화에 따른 샤시계 볼트 체결력 변화 인자 연구)

  • Choi, Dong Young;Choi, Jae Chil;Han, Jong Uk
    • Journal of Auto-vehicle Safety Association
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    • v.7 no.1
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    • pp.20-26
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    • 2015
  • In vehicle development process, durability test should be carried out in field condition. Nowadays there are many customer live there multiple conditions. It makes change of the car's material. Such change causes to lose a bolt. Diversifications of climatic conditions are also a matter of loosening the bolt. To avoid this problem, to identify the cause of the problem, and the solution should be applied. To avoid problems during the durability development test should be measured by the clamping force. Ultrasonic instruments clamping force without affecting the torque can be measured. This instrument is part of the problem by monitoring the clamping force required to obtain objective data.

The effect of Socheongrongtang & Ockbyungpoongsan Gamibang on alle rgic rhinitis. (小靑龍湯 合 玉屛風散 加味方의 알레르기 鼻炎에 對한 治療報告)

  • Kim, Gyung-jun;Chae, Byung-yoon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.11 no.1
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    • pp.284-291
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    • 1998
  • we clinicallly observed 48 patients with allergic rhinitis who visited Kyoung-Won univ. Oriental hospital from 1996. 3 to 1998. 4. Their chief complaints were nasal obstruction, sneezing, watery rhinorrhea. They were also troubled with itching sensation of eye ball, dryness of nasal cavity or throat, photophobia and lacrimation, ect. The results were as follows: 1. In the classification of Sasang constitution, Taeum-group patients visited most frequently and ,the treatment to the taeum-group patients was most effective. 2. There were no differences between inhalant and climatic factor at the improvement rate of allergic initiator. 3. During the aflected time, the shorter termwas the higher improvement rate was. 4. The patients with no complication were treated better than those who accompanied with other nasal diseases.

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Analysis and Evaluation of 3kW Grid-Connected PV System by Field Demonstration Test (3kW급 계통연계형 태양광발전시스템의 실증시험 분석평가)

  • So, Jeong-Hoon;Yu, Gwon-Jong;Jung, Myung-Woong;Jung, Young-Seok;Choi, Ju-Yeop
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.1353-1355
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    • 2003
  • Total six units of 3kW photovoltaic (PV) system and data acquisition system (DAS) are constructed for analyzing performance of PV system at field demonstration test center of Gwang-Ju in Korea. As climatic and irradiation conditions are varied, operation characteristics of the PV system are collected and analyzed in data-acquisition system. Furthermore, not only performance test of each PV system component such as PV module and power conditioning system, but also performance of total PV system e.g. system efficiency, electric power and loss factor at the site are reviewed.

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