• Title/Summary/Keyword: Environmental condition effect

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Analysis on Thermal Environment of Marathon Course in 2011 Daegu World Championship in Athletics (대구 세계육상선수권대회 마라톤 구간의 열환경변화분석)

  • Baek, Sang-Hun;Oh, Sang-Hak;Jung, Yong-Hun;Jung, Eung-Ho
    • Journal of Environmental Science International
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    • v.20 no.7
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    • pp.881-890
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    • 2011
  • In this study, thermal environment changes for a marathon course of IAAF World Championship, Daegu 2011 were modeled to provide improvements of thermal environment, so that runners could have the maximum condition and citizens pleasant streets. The three biggest size of intersections were selected for the study. Envi-met, 3G microclimate model, were used for a thermal environment analysis and three different cases - present status, planting roadside tree scenario, and roof-garden scenario - were compared. The followings are the results of the study. 1. The highest thermal distribution were shown at 1 p.m., but there was no significant difference between a thermal distribution at 1 p.m. and that at 5 p.m. since a heat flux from buildings affects thermal distributions rather than insolation does. 2. Tree planting or adding environmental friendly factors might lead a temperature drop effect, but the effect was not significant for areas covered with impermeability packing materials such as concrete or asphalt (especally, for Site case 2) 3. The combination of tree planting and adding environmental friendly factors also brought a temperature drop effect (Site 1 and 2) and this case showed even better result if green spaces (especially, parks) were closed.

Growth and gut performance of young pigs in response to different dietary cellulose concentration and rearing condition

  • Cho, Hyun Min;Kim, Eunjoo;Wickramasuriya, Samiru Sudharaka;Shin, Taeg Kyun;Heo, Jung Min
    • Animal Bioscience
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    • v.34 no.10
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    • pp.1653-1662
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    • 2021
  • Objective: This experiment was conducted to investigate the effect of insoluble cellulose supplementation to diets on the growth performance, intestinal morphology, the incidence of diarrhea, nutrients digestibility, and inflammatory responses in altering environmental conditions of animals housing. Methods: A total of 108 male pigs (Duroc×[Yorkshire×Landrace]) were randomly allocated to one of three dietary treatments (cellulose 0%, 1%, 2%) and two environmental conditions (good sanitary condition vs. poor sanitary condition) to give 6 replicate pens per treatment with three pigs per each pen at 14 days post-weaning. Results: Pigs were in good sanitary condition had higher average daily gain (p<0.01) and improved feed efficiency (p<0.05) from day 1 to 14 after weaning compared to their counterparts. The interactions were found between environmental conditions and dietary treatments (day 7: crypt depth [p<0.01], villous height to crypt depth [p<0.001]; day 14: crypt depth [p<0.001], villous to crypt ratio [p<0.01]) in ileum morphology. Crypt depth was decreased (p<0.05), and villous to crypt ratio was increased (p<0.05) only in poor sanitary conditions. Pigs exposed to the good sanitary condition had higher (p<0.05) apparent ileal digestibility (day 7, gross energy; day 14, dry matter), apparent total tract digestibility (day 14, dry matter and crude protein) compared to pigs housed in the poor sanitary condition. Meanwhile, pigs fed a diet supplemented with 2% cellulose had decreased (p<0.05) apparent ileal digestibility (day 7, dry matter; day 14, crude protein), apparent total tract digestibility (day 7, dry matter; day 14, crude protein, gross energy) compared to pigs fed a diet supplemented with 0% or 1% cellulose. Conclusion: Our results indicated that a diet supplemented with 1% cellulose increased villous to crypt ratio, however feeding a diet containing cellulose (1% or 2%) impaired nutrient digestibility for 14 day after weaning in both good sanitary and poor sanitary conditions.

A study on the key performance indicator of the dynamic positioning system

  • Park, Kwang-Phil;Jo, A-Ra;Choi, Jin-Woo
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.8 no.5
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    • pp.511-518
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    • 2016
  • The dynamic positioning system (DPS) maintains an offshore vessel's position and heading under various environmental conditions by using its own thrust. DPS is regarded as one of the most important systems in offshore vessels. So, efficient operation and maintenance of the DPS are important issues. To monitor the DPS, it is necessary to define an appropriate key performance indicator (KPI) that can express the condition of the DPS from the perspective of operational efficiency and maintenance. In this study, a new KPI for the DPS is proposed considering the efficiency of the machinery and controller, the energy efficiency, and the environmental conditions in which the DPS is operated. The KPI is defined as a function of control deviation, energy consumption, and environmental load. A normalization factor is used to normalize the effect of environmental load on the KPI. The KPI value is calculated from DPS simulation and model test data. The possibility of applying the KPI to monitoring of DPS condition is discussed by comparing the values. The result indicates the feasibility of the new KPI.

Effect of Some Environmental Factors on Oviposition and Developmental Characteristic of Protaetia brevitarsis and Allomyrina dichotoma (흰점박이꽃무지와 장수풍뎅이의 산란과 발육에 미치는 환경요인)

  • Kim, Ha-Gon;Kang, Kyung-Hong;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.44 no.4 s.141
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    • pp.283-286
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    • 2005
  • This study was carried out to obtain information about a several environmental factors influencing on the bionomical characteristics of Protaetia brevitarsis and Allomyrina dichotoma, which have been used for an important traditional medicinal stuffs. The moisture contents of humus affected the oviposition of P. brevitarsis and A. dichotoma, showing a suitable condition in range of $65{\sim}75%$. Very high or very low moisture condition in humus decreased the egg laying of P. brevitarsis and A. dichotoma, Also, moisture condition of humus was an important factor influencing on the egg and larval survival, egg developmental period, and feeding activity of P. brevitarsis and A. dichotoma.

Changes of residents' indoor environment control behavior as a result of provided education and environmental information (거주자의 실내환경 관리행동에 교육 및 정보제공이 미치는 효과)

  • Bae, Nu-Ri;Choi, Yoo-Rim;Chun, Chung-Yoon
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2006.11a
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    • pp.269-274
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    • 2006
  • The purposes of this research are, first, to investigate the present condition of indoor thermal environment in winter. Second, to find out how residents' knowledge, consciousness, and behavior changed after provided with education and information of indoor climate. Finally, to reveal how this changes make alteration to their indoor environment. Thirty apartments were collected, and then divided into three groups as Control Group, Education Group, and Edu-information Group in order to conduct the purposes. Provided education and environmental information turn out to have a positive effect to residents' knowledge, consciousness, and behavior, and consequently, it leads residents to control their indoor environment more actively in some cases. Thus, it is important to provide residents with environmental education and information, and it should be conducted regularly in order to maximize the positive effect of education since it tends to decrease as time goes by.

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Analysis of Growth Condition and Some Suggestions for Its Maintenance of Legally Protected Trees Grown in Pyungtack City, Kunggi Province, Korea (경기도 평택시 보호수의 생육실태와 관리방안 연구)

  • Lee, Jong-Bum;Doo, Chul-Eon;Lee, Jae-Keun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.3
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    • pp.45-54
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    • 2012
  • This study intended to analyze growth condition of each object by protected tree's ground for 45 places registered to Pyeongtaek protected tree list in locational characteristics, conduct exchange analysis for impediment extent rate in crown area and tree type to the result and suggest the measures to manage artificial impediment which is an effect on protected tree condition. In this study, the tree whose area of impediment for crown area is less than 21% is tree condition of grade 1~2, less than 21~50% is grade 2~3 and more than 50% is grade 3~5. The more impediment is, the more inconvenience causes on growth and development. So, it verified that the area rate must maintain less than 21% for the root system management of protected tree. For the standard of managing artificial impediment which is an effect on the tree condition of protected trees, the below matters intend to be suggested. The first, the impediment in crown area should be less than 21%. But, if there is not artificial impediment out of crown area, the rate of impediment area is considered to increase somewhat. The second, growth space of protected tree should be maintained by crown area at least and impediment should be established out of the crown area. The third, during the national project and land development, surroundings of protected tree must be applied as park, resting place, etc. and the establishment area of impediment (artificial impediment and natural impediment) in crown area must be limited. The forth, publicity for regional people (especially, land owner) is necessary for the protection of natural inheritance and the value of dependence on local government and village which are the subject of management must be announced widely through the internet media, etc, so its importance must be recognized. The fifth, the matters related to protected tree management must be able to limit artificial damage which is for surroundings of protected tree through the mutual connection among the local governments; construction, civil engineering, architecture, water and sewage, agriculture and forest and others. Also, following studies on the effects of kinds, thickness, etc. of impediment around the protected tree on trees should be continued.

Desalinization Effect of Off-season Crop Cultivation in Long-term Oriental Melon Cultivated Plastic Film House Soils (휴경기 후작물 재배에 의한 참외 장기연작 비닐하우스 토양의 제염 효과)

  • Byeon, Il-Su;Chung, Jong-Bae
    • Korean Journal of Environmental Agriculture
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    • v.34 no.4
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    • pp.253-259
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    • 2015
  • BACKGROUND: During the off-season, the cultivation of Chinese cabbage and water dropwort is often used to desalinize plastic film house soils. The objective of this study was to verify the effect of double-cropping systems on the salt removal in oriental melon cultivated plastic film house soils.METHODS AND RESULTS: Electrical conductivity (EC) and soluble salt contents were measured in soils collected from plastic film houses of oriental melon cultivation before and after the off-season crop cultivation. Also the same measurements were performed in the next oriental melon season to estimate the desalinization effect of double-cropping systems. During the cultivation of Chinese cabbage under open-field condition, ECeof surface soil was reduced from 6.0 to 0.8 dS/m. Double-cropping of water dropwort in flooded soil was also efficient in removing the salts accumulated during oriental melon cultivation. In the house soils where salts were removed during the off-season crop cultivation, soil ECewas maintained below 3 dS/m during the next oriental melon cultivation season.CONCLUSION: The off-season cropping under open-field or flooded condition was effective in desalinization of plastic film house soils. Since the salt removal effect is not expected to last for several years, the double-cropping system should be introduced every season to maintain soil EC below the critical level.

An Analysis on Effects of the Initial Condition and Emission on PM10 Forecasting with Data Assimilation (초기조건과 배출량이 자료동화를 사용하는 미세먼지 예보에 미치는 영향 분석)

  • Park, Yun-Seo;Jang, Im-suk;Cho, Seog-yeon
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.5
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    • pp.430-436
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    • 2015
  • Numerical air quality forecasting suffers from the large uncertainties of input data including emissions, boundary conditions, earth surface properties. Data assimilation has been widely used in the field of weather forecasting as a way to reduce the forecasting errors stemming from the uncertainties of input data. The present study aims at evaluating the effect of input data on the air quality forecasting results in Korea when data assimilation was invoked to generate the initial concentrations. The forecasting time was set to 36 hour and the emissions and initial conditions were chosen as tested input parameters. The air quality forecast model for Korea consisting of WRF and CMAQ was implemented for the test and the chosen test period ranged from November $2^{nd}$ to December $1^{st}$ of 2014. Halving the emission in China reduces the forecasted peak value of $PM_{10}$ and $SO_2$ in Seoul as much as 30% and 35% respectively due to the transport from China for the no-data assimilation case. As data assimilation was applied, halving the emissions in China has a negligible effect on air pollutant concentrations including $PM_{10}$ and $SO_2$ in Seoul. The emissions in Korea still maintain an effect on the forecasted air pollutant concentrations even after the data assimilation is applied. These emission sensitivity tests along with the initial condition sensitivity tests demonstrated that initial concentrations generated by data assimilation using field observation may minimize propagation of errors due to emission uncertainties in China. And the initial concentrations in China is more important than those in Korea for long-range transported air pollutants such as $PM_{10}$ and $SO_2$. And accurate estimation of the emissions in Korea are still necessary for further improvement of air quality forecasting in Korea even after the data assimilation is applied.

Effects of Hydro-Climate Conditions on Calibrating Conceptual Hydrologic Partitioning Model (개념적 수문분할모형의 보정에 미치는 수문기후학적 조건의 영향)

  • Choi, Jeonghyeon;Seo, Jiyu;Won, Jeongeun;Lee, Okjeong;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.36 no.6
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    • pp.568-580
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    • 2020
  • Calibrating a conceptual hydrologic model necessitates selection of a calibration period that produces the most reliable prediction. This often must be chosen randomly, however, since there is no objective guidance. Observation plays the most important role in the calibration or uncertainty evaluation of hydrologic models, in which the key factors are the length of the data and the hydro-climate conditions in which they were collected. In this study, we investigated the effect of the calibration period selected on the predictive performance and uncertainty of a model. After classifying the inflows of the Hapcheon Dam from 1991 to 2019 into four hydro-climate conditions (dry, wet, normal, and mixed), a conceptual hydrologic partitioning model was calibrated using data from the same hydro-climate condition. Then, predictive performance and post-parameter statistics were analyzed during the verification period under various hydro-climate conditions. The results of the study were as follows: 1) Hydro-climate conditions during the calibration period have a significant effect on model performance and uncertainty, 2) calibration of a hydrologic model using data in dry hydro-climate conditions is most advantageous in securing model performance for arbitrary hydro-climate conditions, and 3) the dry calibration can lead to more reliable model results.

Design of convection current circulation system in reservoir using CFD simulation (CFD모사를 이용한 저수지 물순환장치 유동 설계)

  • Lee, Yosang
    • Journal of Environmental Impact Assessment
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    • v.21 no.1
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    • pp.133-142
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    • 2012
  • Convection Current Circulation System(CCCS) in stratified reservoir controls development of anaerobic condition and algal bloom during summer. In order to increase the CCCS effectiveness, we analyze diverse design parameters to make optimize the flow pattern in reservoir. In this study, we interpret the internal flow with installation and operation condition of CCCS based on CFD in reservoir. Design variables of CCCS is reservoir depth, stratification strength, distance of between CCCS and so on. Since reservoir depth and stratification strength in variables is depending on natural phenomenon, we evaluated current circulation effect by distance of CCCS and proposed the optimal design condition using CFD simulation. Flow and diffusion changes in water body was assessed by temperature and dye test. Changes in water floor temperature at 40m intervals was slowly descending over 37 hours. Dye diffusion simulation at 60m intervals, the radius of the spread between two devices were overlapped after 12 hours.