• Title/Summary/Keyword: Field Environment

Search Result 8,421, Processing Time 0.034 seconds

Development of a New E-$\varepsilon$ Turbulence Model for Analysing the Air Flow Field within an Urban Street Canyon (도시협곡내 유동장 해석을 위한 새로운 E-$\varepsilon$ 난류 모델의 개발)

  • 정상진;박옥현
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.15 no.3
    • /
    • pp.281-289
    • /
    • 1999
  • A new E-$\varepsilon$ turbulence numerical model is proposed for analysing the turbulent air flow field within are urban street canyon. In this model the equations of eddy viscosity and energy dissipation ae reformed by considering the Kolmogorov time scale and streamline curvature effect. Application results of the new E-$\varepsilon$ model have been compared with those of standard E-$\varepsilon$ model and Yang and Shih's one, which are commonly used ones in engineering fields, and with field experiment results of DePaul and Sheih. The new model appears to be generally superior to other both models in the prediction of an air flow field within street canyon.

  • PDF

A Case Study on Cut Slope Failure due to the Geomorphological Factor (지형요인에 의한 절토사면 붕괴사례)

  • Kim, Seung-Hyun;Choi, Ji-Yong;Rhee, Jong-Hyun;Lee, Jung-Yup;Koo, Ho-Bon
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.03a
    • /
    • pp.1161-1170
    • /
    • 2009
  • The Roads in Gangwon Province generally was made on purpose to use the military road. In case of these roads, tremendous dangerous cut slopes do exist and its road linear shape was badly designed. In order to make up for this situation, the government has continuously established the new road or performed the public works such as the straight line of the curved road. Soksil 2 cut slope was made through the road improvement work. This has small surface failures and collapses. In spite of dry season, this slope are leaking lots of groundwater at the unbelievable point. So as to get curious phenomenon right, we performed a detailed field investigation, the geomorphological analysis, the stability analysis considering field characteristic and ultimately proposed the countermeasure to make sure stability of Sokil 2 cut slope.

  • PDF

Dose Evaluation of Neutron within Containment Building of a CE type Nuclear Power Plant (CE형 원전의 격납건물내 중성자선량 평가)

  • Kim Tae Wook;Han Jae Mun;Kim Kyung Doek;Yun Cheol Whan;Suh Jang Soo;Kim Young Jae
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.3 no.1
    • /
    • pp.23-30
    • /
    • 2005
  • From measured results of the neutron fields at some principal places within the containment building in a CE type nuclear power plant in operation, the radiation exposure of a worker to the neutron at there was evaluated and the equivalent dose reflecting new recommendation (ICRP 60) was compared with that doing the old one (ICRP 26). The measured neutron field was also compared with calibration neutron field. From the analysis, the following conclusion was obtained: the average neutron radiation weighting factor according to new recommendation is 2.41 to 2.71 times higher than the old one. The average neutorn radiation weighting factor at the measured place was similar to that at calibration neutron field. The average neutron energy at measured place was between 42 and 158 keV and higher than that of calibration field of 500 keV. So, the measured equivalent dose in nuclear power plant could be overestimated compared to the real equivalent dose.

  • PDF

Evaluating Heavy Metal Stabilization Efficiency of Chemical Amendment in Agricultural Field: Field Experiment (안정화제 처리에 따른 중금속 오염 농경지 복원의 효율성 평가: 현장실증시험)

  • Oh, Se-Jin;Kim, Sung-Chul;Yoon, Hyun-Soo;Kim, Ha-Na;Kim, Tae-Hwan;Yeon, Kyu-Hun;Lee, Jin-Soo;Hong, Sung-Jo;Yang, Jae-E.
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.44 no.6
    • /
    • pp.1052-1062
    • /
    • 2011
  • Residual of heavy metals originated from abandoned metal mines in agricultural field can cause adverse effect on ecosystem and eventually on human health. For this reason, remediation of heavy metal contaminated agriculture field is a critical issue. In this study, five different amendments, agriculture lime, dolomite, steel slag, zeolite, and compost, were evaluated for stabilization efficiency of heavy metals in agricultural field. Applied mixing ratio of amendments was varied (2% or 6%) depending on properties of amendments. Result showed that soil pH was increased compared to control (6.1-6.7) after mixing with amendments and ordered as dolomite (7.2~8.3) > steel slag (6.7~8.1) > agriculture lime (6.6~7.4) > zeolite (6.2~6.9) > compost (6.1~7.1). Among other amendments, agriculture lime, steel slag, and dolomite showed the highest stabilization efficiency of heavy metals in soil. For Cd, stabilization efficiency was 49~72%, 51~83%, and 0~36% for agriculture lime, steel slag, and dolomite respectively. In case of Pb, 43~64, 37~73%, and 51~73% of stabilization efficiency was observed for agriculture lime, steel slag, and dolomite respectively. However, minimal effect of heavy metal stabilization was observed for zeolite and compost. Based on result of this study, amendments that can increase the soil pH were the most efficient to stabilize heavy metal residuals and can be adapted for remediation purpose in agricultural field.

Diurnal and Seasonal Variations in Mid-Latitude Geomagnetic Field During International Quiet Days: BOH Magnetometer

  • Hwang, Junga;Kim, Hyang-Pyo;Park, Young-Deuk
    • Journal of Astronomy and Space Sciences
    • /
    • v.29 no.4
    • /
    • pp.329-336
    • /
    • 2012
  • Korea Astronomy and Space Science Institute researchers have installed and operated magnetometers at Bohyunsan Observatory to measure the Earth's magnetic field variations in South Korea. In 2007, we installed a fluxgate magnetometer (RFP-523C) to measure H, D, and Z components of the geomagnetic field. In addition, in 2009, we installed a Overhauser proton sensor to measure the absolute total magnetic field F and a three-axis magneto-impedance sensor for spectrum analysis. Currently three types of magnetometer data have been accumulated. In this paper, we use the H, D, Z components of fluxgate magnetometer data to investigate the characteristics of mid-latitude geomagnetic field variation. To remove the temporary changes in Earth's geomagnetic filed by space weather, we use the international quiet days' data only. In other words, we performed a superposed epoch analysis using five days per each month during 2008-2011. We find that daily variations of H, D, and Z shows similar tendency compared to previous results using all days. That is, H, D, Z all three components' quiet intervals terminate near the sunrise and shows maximum 2-3 hours after the culmination and the quiet interval start from near the sunset. Seasonal variations show similar dependences to the Sun. As it becomes hot season, the geomagnetic field variation's amplitude becomes large and the quiet interval becomes shortened. It is well-known that these variations are effects of Sq current system in the Earth's atmosphere. We confirm that the typical mid-latitude geomagnetic field variations due to the Sq current system by excluding all possible association with the space weather.

An Importance Analysis of Planning Factors for Constructing Environmental-Friendly Industrial Estate (환경친화적 산업단지 조성을 위한 계획요소의 중요도 분석)

  • Lee, Eun Yeob;Kim, Jung Kon;Lee, Hyun Ju
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.15 no.4
    • /
    • pp.1-11
    • /
    • 2012
  • This study prepared the list of planning components required for constructing environment-friendly industrial complex and grasped major environment-friendly planning components by measuring the importance per each planning component via the survey for specialists. As a result of measuring the importance of planning component according to each field for constructing environment-friendly industrial complex, it is indicated that important planning components in natural environment field are establishing complex location plan considering its configuration and slope, excluding projects for steep slope-land, establishing countermeasures for reducing contaminants per its source, and separated location of contamination industry around living space. In living environment field, proposed planning components having relatively high importance are separated location of pollution causing industry, establishing energy saving land use plan, linking with green way, circulation network plan, lowering noise level at roadside, plan for separating between pedestrian and vehicle, securing parking space, extending green park and proper location, installing green buffer zone, conserving and forming landscapes, land use for raising energy efficiency, and expansion of energy source. In case of ecological environment, core planning components such as conserving upper class of ecological naturality degree, conserving main habitat, and biotope forming plan are suggested. This study is limited to find out planning components for constructing environment-friendly physical environment of industrial complex which is a part of non-production process. The approach to solve environmental problem by linking spatially production process and non-production process. There is a need to conduct follow-up study to constructing technique for environment-friendly industrial complex considering production & nonproduction process afterward.

A basic study on human error proneness in computerized work environment (전산화된 작업환경에서 인간의 오류성향에 관한 기초연구)

  • Jeong, Gwang-Tae;Lee, Yong-Hui
    • Journal of the Ergonomics Society of Korea
    • /
    • v.19 no.1
    • /
    • pp.1-9
    • /
    • 2000
  • This study was performed to investigate some characteristics on human error proneness in the computerized work environment. Our concerning theme was on human error likelihood according to personal temperament. Two experiments were performed. The first experiment was to study the effect of field- independence/dependence on error likelihood. The second experiment was on error proneness. These experiments were performed in information search task. which was most frequent task in computerized work environment such as the control room of nuclear power plant. Ten subjects were participated in this study. Analyzed results are as follows. Field-independence/dependence had a significant effect in both information search time and error frequency. Error proneness had a significant effect in both factors, too. And, a positive correlation was found between error frequency and information search time. These results will be utilized as a basis to study operator's error proneness in the computerized control room of nuclear power plant. later on.

  • PDF

Developing Performance Indicator for Smart-Exhibition (스마트 전시환경의 전시회 성과평가를 위한 지표 개발)

  • Choe, Jae-Ho;Moon, Hyun-Sil;Kim, Jae-Kyeong
    • Journal of Information Technology Services
    • /
    • v.13 no.2
    • /
    • pp.71-82
    • /
    • 2014
  • Exhibitions are important sales promotional method commonly used by the marketer of industrial products. Exhibition utilized as a means of effective marketing tools, company's interest and demand is rising. Especially in recent years, visitors' activity within the exhibition space can be monitored in real time by applying near-field sensing technology such as RFID, NFC, RQ code. Exhibition organizers are also applying the near-field sensing technology in order to attract the participating companies and visitors. With the introduction of near-field sensing technology, the exhibition has been a lot of changes occur in the exhibition environment. However absence of performance indicators to measure new exhibition environment which adopt ubiquitous technology, still the exhibition performance is not properly measured. In this study, we use the Delphi technique with the performance indicators based on previous research, and propose performance indicators for measuring achievement of exhibition in the smart-exhibition environment.

Obstacle Avoidance for AUV using CAPM (CAPM을 이용한 AUV의 장애물 회피)

  • 양승윤
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.4 no.2
    • /
    • pp.17-29
    • /
    • 2001
  • In this paper, we designed the hybrid path generation method which is named CAPM(Continuous path generation method based on artificial Potential field) that is able to be used in the obstacles environment. This CAPM was designed so that it puts together two obstacle avoidance algorithm-the continuous path generation method(CPGM) and the artificial potential field method(APFM). Here, the CAPM generate the safety path using continuous path curvature. But, this method has demerits when used in obstacles environment in which are closely located. Another method which is named the APFM generates the path with the artificial potential field in the obstacles environment. But, It has local minima in certain places and unnecessarily calculates the path in which obstacles are not located. So, the CAPM was designed for autonomous underwater vehicle(AUV) obstacle avoidance. As the result of simulation, it was confirmed that the CAPM can be applied to a safe path generation for AUV.

  • PDF

Effects of Cognitive Styles and Navigation in HyperSpace Learning Environment (하이퍼스페이스 학습 환경에서의 인지 형태와 네비게이션의 교육 효과에 관한 연구)

  • Ahn, Mi-Lee
    • The Transactions of the Korea Information Processing Society
    • /
    • v.4 no.12
    • /
    • pp.3023-3032
    • /
    • 1997
  • This study examined individual differences in navigating in hyperspace learning environment where a minimum structure is provided. Using a hypercard stack called "Pearl Harbor", Field Dependent people used guidance more often than those in Field Indepedent; FI achieved scored higher at the end of the study; and FI people had some type of pattern showing from them audit trail when FD people did not show any trail of patterns. Also people with higher visual thinking scores achieved higher scores in hyperspace environment.

  • PDF