• Title/Summary/Keyword: Investigation environment factor

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Heat Transfer and Flow Characteristics in an Annulus Filled with Aluminum Foam (발포 알루미늄이 삽입된 환형관에서의 열전달 및 유동특성)

  • Noh Joo-Suk;Han Young-Hee;Lee Kye-Bock;Lee Chung-Gu
    • Journal of Energy Engineering
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    • v.15 no.1 s.45
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    • pp.60-66
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    • 2006
  • An experimental investigation on the flow and convective heat transfer characteristics has been carried out far aluminum foam heat sink inserted into the annulus to examine the feasibility as a heat sink. Two aluminum foams or different permeability were selected to provide the friction factor and heat transfer correlations as function of Darcy, Reynolds and Prandtl number. Experimental results show that the friction factor is higher than clear annulus without aluminum foam, while $6\sim10$ times augmentation in Nusselt number is obtained. This technique can be used for the compactness of the heat exchanger.

Experimental Investigation of the Effects of Learning Environment and The Nature of Educational Program on the Outcome of Creativity Training (온라인 창의성 교육에 있어 학습 환경과 교육 프로그램의 특성에 관한 실증연구)

  • 조남재;하주현
    • Journal of the Korean Operations Research and Management Science Society
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    • v.27 no.3
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    • pp.135-144
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    • 2002
  • The purpose of this study is to examine the effects of computer-based creativity training. Four groups of vocational high school students totaling 151 were used as experimental subjects. Two dimensions of treatment were designed. One treatment dimension is the use of computer medium in education: computer based vs. paper-pencil setting of education. The second treatment dimension is the method of creativity training: technique-oriented training program vs. factor-oriented training program. Both a pretest and a post-test were administered to all participated students. The tests were composed of a Creative Figural Test and a Creative Product Test. After the pretest 8 sessions of creative training were delivered as intended in the design of the experiment. The Dost-test was arranged a week after the completion of the training sessions. The results of the study include: First, all the 4 groups showed certain amount of improvements in their scores of Creative Figural Test, while no improvements was observed in the creative product test score. Second, the technique-oriented creativity training was more effective than the factor-oriented under the context of computer-based education, and the factor-oriented training was more effective in the paper-pencil setting. The results suggest that different pedagogical approaches should be employed for computer-based training as compared to the paper-pencil education.

The Effects of the High School Students' Time Management Behavior on Satisfaction with Educational Consumption and School Life (고등학생의 시간관리행동에 따른 교육소비만족도 및 학교생활만족도)

  • Lee, Kyoung Min;Lee, Seung Sin
    • Human Ecology Research
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    • v.53 no.1
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    • pp.1-16
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    • 2015
  • This study aims to examine the effects of high school students' time management behaviors on their satisfaction with educational consumption and school life. Three hundred seventy-six high school students in Seoul participated in this investigation. The SPSS ver. 19.0 program was adopted for the descriptive analysis, factor analysis, Cronbach's ${\alpha}$, and multiple regression analysis. The results of the present study can be summarized as follows: first, the levels of time management behavior, satisfaction with educational consumption at school, and satisfaction with school life were relatively high. Second, an analysis of the relative influence on satisfaction with educational consumption revealed that the students' time management behavior was the most influential factor, followed by academic achievement. As the levels of time management behavior and academic achievement were high, the level of satisfaction with educational consumption was high. Finally, an analysis of the relative influence of satisfaction with school life also revealed that the students' time management behavior was the most influential factor, followed by academic achievement. Based on the findings, that is, the effects of high school students' time management behavior and other involved variables on their satisfaction with educational consumption and school life, a future study can present specific ways to enhance the level of satisfaction with educational consumption and school life.

Fuzzy Inference-based Quantitative Estimation of Environmental Affecting Factor For Performance-based Durability Design of RC Structure Exposed to Salt Attack Environment (염해 환경에 노출된 RC 구조물의 내구성능설계를 위한 퍼지 추론 기반 환경영향지수의 산정)

  • Do Jeong Yun;Song Hun;Soh Seung Young;Soh Yang Seob
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.237-240
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    • 2005
  • As a part of the effort for improving the durability design based on a set of the deem-to-satisfy specifications, it is important and primary to quantitatively identify the environmental impact to a target reinforced concrete structure. In this work, an effort is made to quantitatively calculate the environmental affecting factor with using a fuzzy inference that it indicates the severity of environmental impact to the exposed reinforced concrete structure or member. This system is composed of input region, output region and rule base. For developing the fuzzy inference system surface chloride concentration{chloride), cyclic degree of wet and dry(CWD), relative humidity(RH) and temperature (TEMP) were selected as the input parameter to environmental affecting factor(EAF) of output parameter. The Rules in inference engine are generated from the engineering knowledge and intuition based on some international code of practises as well as various researcher's experimental data. The devised fuzzy inference system was verified comparing the inferred value with the investigation data, and proved to be validated. Thus it is anticipated that this system for quantifying EAF is certain to be considered into the starting point to develop the performance-based durability design considering the service life of structure.

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River Embankment Integrity Evaluation using Numerical Analysis (수치해석을 이용한 하천제방의 건전도 평가)

  • Byun, Yo-Seph;Jung, Hyuk-Sang;Kim, Jin-Man;Choi, Bong-Hyuck;Kim, Kyung-Min;Chun, Byung-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.524-528
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    • 2009
  • An influence factors for soundness evaluation of river levee include resistibility and embankment for piping of ground consisting embankment in case piping, permeability coefficient of ground, height of embankment, the width of crest, material characteristics of embankment and foundation ground, shape of embankment slope, an influence for penetration of rainfall or river water in case slope stability. In this study, it was operated a feasibility investigation of existing design result, stability evaluation for permeability coefficient use and permeability coefficient change of foundation ground to investigate an influence in line with permeability coefficient change for result of river levee penetration analysis. The evaluation results of influence factors, the permeability coefficient used in design and it was evaluated influence in safety factor of piping. After the evaluation of influence factors, the permeability coefficient used in the design appears with the fact that differs in a design report about same soil, Accordingly, the stability investigation of embankment by application of literature data can affect stability evaluation results by change factors like a permeability coefficient, void ratio. It should be certainly used material properties by a test in soundness evaluation of river levee.

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Studies on Pollution Characteristics and Sources of Precipitation in Jeiu Island

  • Kang, Chang-Hee;Kim, Won-Hyung
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E4
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    • pp.191-201
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    • 2002
  • The pH, electric conductivity. and the major ionic components were analyzed for the precipitation samples collected at 1100 Site of Mt. Halla and Jeju city. The quality of analytical data was verified by the comparison of ion balances, conductivities and acid fractions, all of which correlation coefficients were over 0.952. The ionic strengths lower than 10$^{-4}$ M were found in 57 and 28% at 1100 Site and Jeju city respectively. The precipitation in Jeju city was influenced more by the oceanic effect than those in 1100 Site. The acidification of precipitation was caused mostly by S $O_4$$^{2-}$and N $O_3$$^{[-10]}$ in both areas, and the organic acids have contributed to the acidity with only 7~8%. The neutralization factors by N $H_3$ were about 44 and 47% at the 1100 site and the Jeju city, respectively, whereas those by CaC $O_3$were 21 and 24%, and the free acidity were about 38 and 28% at two sites. From the investigation of seawater and soil enrichment factors, the S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ and N $E_4$$^{+}$ were immigrated by other sources rather than from the seawater or soil origins. but not in the case of $Mg^{2+}$, C $l^{[-10]}$ , N $a^{+}$, and $K^{+}$. Factor analysis has shown that the precipitation at the 1100 site had been influenced mostly by anthropogenic sources, followed by soil and sea-water sources. On the other hand, the precipitation at the Jeju city was mainly influenced by oceanic sources, followed by anthropogenic and soil sources.urces.

A Study on the Basis of Environmental Marketing in interior Space design (실내 공간 디자인에서의 환경마케팅에 관한 기초연구)

  • Woo, Su-Jin;Han, Hae-Ryon
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2007.11a
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    • pp.139-144
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    • 2007
  • Although human beings have been able to lead the affluent life owing to industrialization and development of science and technology, as the result of this, the nature has be destroyed, energy consumption has been accelerated, urban area has got wide and the nature has got narrow. In the face of such critical situations, concerns have been aroused to environment. In order to minimize the environment destruction and accompany the aesthetic, efficient and advantage methods, environmental marketing has been introduced to indoor. Environmental marketing is the marketing that minimizes the reverse function so as to obtain the satisfactory result, and it is still in the stage of fundamental investigation. stage. As the concept and type of environmental marketing have not been established yet for interior design, environmental marketing currently applied to indoor space is classified Into three types in this study. Through the four types of environmental marketing, which are the introduction of natural elements to indoor space, the use of eco-friendly materials and the use of sustainable materials, renovation it is intend to derive the environmental marketing strategy and present the sequence of strategy establishment and desirable direction in environmental marketing.

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Investigation of Effect of Input Ground Motion on the Failure Surface of Mountain Slopes

  • Khalid, Muhammad Irslan;Pervaiz, Usman;Park, Duhee
    • Journal of the Korean GEO-environmental Society
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    • v.22 no.7
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    • pp.5-12
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    • 2021
  • The reliable seismic stability evaluation of the natural slopes and geotechnical structures has become a critical factor of the design. Pseudo-static or permanent displacement methods are typically employed to evaluate the seismic slope performance. In both methods, the effect of input ground motion on the sliding surface is ignored, and failure surface from the limit equilibrium method is used. For the assessment of the seismic sensitivity of failure surface, two-dimensional non-linear finite element analyses are performed. The performance of the finite element model was validated against centrifuge measurements. A parametric study with a range of input ground motion was performed, and numerical results were used to assess the influence of ground motion characteristics on the sliding surface. Based on the results, it is demonstrated that the characteristics of input ground motion have a significant influence on the location of the seismically induce failure surface. In addition to dynamic analysis, pseudo-static analyses were performed to evaluate the discrepancy. It is observed that sliding surfaces developed from pseudo-static and dynamic analyses are different. The location of the failure surface change with the amplitude and Tm of motion. Therefore, it is recommended to determine failure surfaces from dynamic analysis

Induced Expression of Doublesex-and mab-3-related Transcription Factor-1 (DMRT-1) mRNA by Testosterone in the Olive Flounder, Paralichthys olivaceus ovary (Testosterone 처리에 의한 넙치, Paralichthys olivaceus 난소에서 doublesex-and mab-3-related transcription factor-1 (DMRT-1) mRNA의 발현 유도)

  • Jo, Pil-Gue;An, Kwang-Wook;Kim, Na-Na;Choi, Yong-Ki;Cho, Sung-Hwoan;Min, Byung-Hwa;Lim, Han-Kyu;Choi, Cheol-Young
    • Journal of Aquaculture
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    • v.20 no.3
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    • pp.199-202
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    • 2007
  • We isolated a 317 bp of partial cDNA for doublesex-and mab-3-related transcription factor-1 (DMRT-1) from the testis of olive flounder, Paralichthys olivaceus using RT-PCR. Based on the multiple sequence alignment, olive flounder DMRT-1 shared relatively high sequence homology (82 to 94%) with orthologues from other teleost species such as Atlantic halibut, Hippoglossus hippoglossus, black porgy, Acanthopagrus schlegeli and rainbow trout, Oncorhynchus mykiss. DMRT-1 mRNA was predominantly expressed in the testis of olive flounder. In our investigation for the effect of testosterone treatment in vivo on induced expression of ovarian DMRT-1 transcript, mRNA levels of DMRT-1 in ovary were significantly up-regulated by testosterone treatments (0.3 or $3.0{\mu}g$ testosterone/g body weight for 12 to 36 hours) as judged by RT-PCR analysis. In overall, transcriptional stimulation of DMRT-1 during treatments was more affected by doses of testosterone than treatment durations. This result strongly suggests that the regulation of DMRT-1 be tissue- and gender-specific in olive flounder, and also provides useful baseline knowledge on the testosterone-mediated regulation in the reproductive physiology of this species.

A Study on the Regional Regeneration Analysis for Urban Regeneration in Busan (도시재생을 위한 부산시의 재생지역 분석에 관한 연구)

  • Kim, Heung-Kwan;Kang, Gi-Cheol
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.1
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    • pp.167-177
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    • 2008
  • The Urban Regeneration can improve physical, environment, economy, life and culture of retarded urban area to recover vitality and to recreate residing environment having competitiveness. This study constructed buildings database to investigate deterioration of buildings of each dong that was minimum administrative region classified for administrative convenience, and spatial structure analysis for Urban Regeneration in Busan. Legal standards have not been established yet. Therefore, the study conducted quantitative analysis based on the Law of Urban and Dwelling Environment Improvement as well as the Special Law of Promotion of Urban Reorganization to find out problems of existing legal systems and to make use of investigation results as basic material of Urban Regeneration project in the future. And, the study investigated physical deterioration of buildings, and characteristics and types of the variables such as population, welfare, business entities at each dong, that is to say, basic administration unit of the government through Factor-Analysis.

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