• Title/Summary/Keyword: environment condition

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Thermal Characteristics Analysis of Pre-Treated Rayon Fibers for Preparing Activated Carbon Fibers (활성탄소섬유 제조시 전처리된 레이온 섬유의 열특성 분석)

  • Choi, Sang Seun;Lee, Soon Hong
    • Journal of the Korean Society of Safety
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    • v.29 no.4
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    • pp.61-72
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    • 2014
  • The aim of this study is to define the condition of optimal pre-treatment for preferable activated carbon fibers (ACFs), which are based on rayon fibers. This paper shows the ideal path of ACFs preparation process; implies that rayon fibers are pre-treated by various solvents with different times before the heating process. The pre-treated rayon fibers finally turned into desirable rayon fiber-based ACFs through optimal pre-treatment condition by heating processes. The thermal analysis method of pre-treated rayon fibers by thermo-gravimetry analyser (TGA) is an idealized tool, which analyzes the best thermal condition of pre-treatment process. Surface morphologies of resulting rayon fibers based ACFs were examined by scanning electron microscope(SEM). The results of TGA and SEM analyses show that the optimal pre-treatment condition for preparing ACFs was clearly defined, in terms of thermal stability and surface morphology.

Properties of Water Permeability and Porosity of Cement Mortar Substrate Coated with Siliceous Slurry Coating under Exposure Enviorment (폭로환경하에서 규산질미분말혼합 시멘트계 도포방수재가 바탕모르터의 투수성과 세공구조에 미치는 영향)

  • 김형무;오상근
    • Proceedings of the Korea Concrete Institute Conference
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    • 1996.10a
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    • pp.175-182
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    • 1996
  • This paper deals with the properties of water permeability and porosity of cement mortar substrate coated with siliceous slurry coating under the exposure environment. Conditions of exposure enviornment are four kinds of in constant temperature water and humidity box, in indoor and outdoor exposure. Coated mortar substrate was expected continually increase in water and humidity condition, but was not in dry condition. Watertightness effect of siliceous coating was better in the condition of humidity then the dry condition, and the pore volume was decreased in that condition.

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An Experimental Study on the Temperature and Humidity Evaluation in the Summer and Winter Season of the Korean Traditional Houses in Chonnam Province (전남지방 전통주택 하절기와 동절기의 온습도 평가에 관한 실험적 연구)

  • Lee, Tai-Kang;Choi, Eun-Seok;Kim, Hang;Kim, Hyung-Ryul;Gi, No-Gab;Kim, Sun-Woo
    • KIEAE Journal
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    • v.6 no.1
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    • pp.57-62
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    • 2006
  • Korean Traditional houses has been evolved and developed in many years, adopting the natural environment to control exterior conditions. These control method are various passive system of using natural materials, considering micro climate, building lay out, and these system are more natural and ecological to make the comfortable indoor climate than active systems of the present houses. This study aims to analyzed control performance of outdoor environment of five Korean traditional houses during the summer and winter. These houses are varied with lay out and floor plan to reflect the way of control for environmental condition, surveyed the reverberation time and sound level difference between rooms of the main living room and other main floored room, master room and kitchen. Especially air temperature and humidity have been measured simultaneously in each rooms to compare with outdoor condition. As a result, the variation of air temperature and humidity of most rooms are considerably static while condition of outdoors are much varied, it is showed that indoor climate has been controled with traditional soiled walls.

Relation Analysis between the Settlement Condition and Life Satisfaction for Rural Residents - Focusing on Jeollabukdo - (농촌주민의 정주여건 인식과 생활만족도의 관계 분석 - 전라북도 농촌지역을 대상으로 -)

  • Ji, Nam-Seok;Lee, Chang-Woo
    • Journal of Korean Society of Rural Planning
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    • v.19 no.4
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    • pp.55-71
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    • 2013
  • This study of the living environment for rural residents to identify the relationship between perception and satisfaction are as. Jeollabukdo rural residents survey and SPSS 18.0 statistical program utilizes improvement of rural environment and living conditions were discussed. The main analysis results are summarized as follows. First, rural residents use the facility convenience and accessibility, economic burden, there was a tendency to recognize the important, good natural environment or their children / relatives for the distance was a low awareness. Second, the location and land a job for men, the women have a higher awareness of the use of public transportation inclination showed less than 50 age group showed higher awareness. Third, the rural living environment of residents' satisfaction with 3.544, and overall satisfaction with village life showed a high propensity men have higher satisfaction than women. Finally, the living environment for the perception and satisfaction with the relationship between residential stability and economic awareness of a higher living environment was found that high satisfaction. These findings further improve the rural environment, improve satisfaction in that you can plan the basis for an effective strategy can be. More sustainable in the future, including the analysis of various parameters in progress by being linked to policy measures that will be provided.

Effect of Field of View on Egocentric Distance Perception in Real and Virtual Environment (현실과 가상현실에서 시야각이 자기중심적 거리지각에 미치는 영향)

  • Jin, Seungjae;Kim, Shinwoo;Li, Hyung-Chul O.
    • Science of Emotion and Sensibility
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    • v.24 no.4
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    • pp.17-28
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    • 2021
  • The purpose of the research was to examine the effect of field of view on egocentric distance perception in the real and virtual environment. The replica that mimicked the real environment condition was used to create the virtual environment condition. We manipulated field of view levels equally in both viewing conditions using glasses that limit the field of view in real-world conditions and limiting the field of view in virtual-world conditions in a manner equivalent to real-world conditions via HMD. Eighteen participants observed the target with a limited field of view in a real and virtual environment without head movement. Then, we measured perceived distance using the timed imagined walking method, which measures the time taken by each participant to mentally walk to the target. The target was shown three times at three different distances from the participants: 3, 4, and 5 m. For the analysis, we converted time estimates into distance estimates. Consequently, the estimated distance in the virtual environment condition was less than the estimated distance in the real environment condition. And as the field of view shrank, the estimated distance also decreased. The estimated distance did not vary with field of view levels in real-world conditions. In the virtual environment, the estimated distance decreased as the field of view decreased, whereas in the real environment, the estimated distance increased. The implications of the results and some future research directions are discussed below.

A Study on Job Techinique of Aquarium related Prospective Occupation in Korea (우리나라 수족관 관련 유망 직업의 직무기술에 관한 연구)

  • KIM, Sam-Kon;HA, Eun-Jong
    • Journal of Fisheries and Marine Sciences Education
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    • v.21 no.2
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    • pp.213-229
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    • 2009
  • The purpose of this study is not only to provide students in the fishery high schools with source materials and opportunity, but also to contribute to a comprehensive development in educational program of the fishery high schools. It investigated various factors of aquarium related 6 new occupations : job contents, educational-level for job performance, training period, worker's capacity, the degree of physical activity, working place, and working environment. First, the work intensity is a normal work. The physical activities such as crawling, bending, accurately seeing a nearby thing and using hands are frequently used. The work is mainly conducted inside a room. The condition for a work environment is very moist and humid. Second, the work intensity is a light work. The physical activities such as using hands, speaking and accurately seeing a nearby thing are frequently used. The work is mainly conducted inside and outside a room. The work environment factor did not have any effect on the work. Third, the work is mainly conducted inside and outside a room. The risk in the condition for a work environment is found out as miscellaneous. Fourth, the physical activities such as bending, touching, and accurately seeing a nearby thing are frequently used. The work is mainly conducted inside a room. The work environment factor did not have any effect on the work. Fifth, the work is mainly conducted inside a room. The condition for a work environment is very moist and humid. Sixth, the work is mainly conducted inside a room. The work environment factor did not have any effect on the work.

Evaluation on the Degree of Satisfaction with Working Environment for Workers Engaged in the Composting Plant with Livestock Manure in the Han-river Watershed (한강유역 축분퇴비공장 근로자의 작업환경 만족도 평가)

  • Kim, K.Y.;Choi, H.L.;Kim, C.N.
    • Journal of Animal Science and Technology
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    • v.44 no.2
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    • pp.261-270
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    • 2002
  • This study was executed to elucidate the degree of satisfaction with working environment and the factors affecting it for workers who are engaged in the composting plants with livestock manure in the Han-river watershed. As an evaluation on site, we applied the self-administered questionaire including general characteristics, working conditions, degree of satisfaction with working environment, and degree of satisfaction with working condition. Simultaneously, we analysed the exposure levels of odor (ammonia, hydrogen sulfide, and odor intensity) in the boundary area of plants. As a result of the study, health condition, odor, work load, dust, and smoking were proved to be the main factors affecting the degree of satisfaction with working environment for workers who are employed in the composting plants with livestock manure in the Han-river watershed. Of them, it was investigated that health condition, odor, and work load accounted for 61.3% of the total degree of satisfaction with working environment and health condition(p$<$0.01), odor(p$<$0.05), work load(p$<$0.05), and dust(p$<$0.05) were statistically significant. It was concluded that the degree of satisfaction with working environment was high for the workers who had good health status and low for the workers who had the relatively considerable work load and were often exposed to odor and dust. Therefore, to increase the degree of satisfaction with working environment for workers who are engaged in the composting plants with livestock manure, the measures that can reduce the exposure levels of odor and dust emitting from the composting plant with livestock manure should be improved.

The Modified Eulerian-Lagrangian Formulation for Cauchy Boundary Condition Under Dispersion Dominated Flow Regimes: A Novel Numerical Approach and its Implication on Radioactive Nuclide Migration or Solute Transport in the Subsurface Environment

  • Sruthi, K.V.;Suk, Heejun;Lakshmanan, Elango;Chae, Byung-Gon;Kim, Hyun-su
    • Journal of Soil and Groundwater Environment
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    • v.20 no.2
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    • pp.10-21
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    • 2015
  • The present study introduces a novel numerical approach for solving dispersion dominated problems with Cauchy boundary condition in an Eulerian-Lagrangian scheme. The study reveals the incapability of traditional Neuman approach to address the dispersion dominated problems with Cauchy boundary condition, even though it can produce reliable solution in the advection dominated regime. Also, the proposed numerical approach is applied to a real field problem of radioactive contaminant migration from radioactive waste repository which is a major current waste management issue. The performance of the proposed numerical approach is evaluated by comparing the results with numerical solutions of traditional FDM (Finite Difference Method), Neuman approach, and the analytical solution. The results show that the proposed numerical approach yields better and reliable solution for dispersion dominated regime, specifically for Peclet Numbers of less than 0.1. The proposed numerical approach is validated by applying to a real field problem of radioactive contaminant migration from radioactive waste repository of varying Peclet Number from 0.003 to 34.5. The numerical results of Neuman approach overestimates the concentration value with an order of 100 than the proposed approach during the assessment of radioactive contaminant transport from nuclear waste repository. The overestimation of concentration value could be due to the assumption that dispersion is negligible. Also our application problem confirms the existence of real field situation with advection dominated condition and dispersion dominated condition simultaneously as well as the significance or advantage of the proposed approach in the real field problem.

A Study in the Directory Service Protocol in Distributed Environment (분산환경에서의 디렉토리 서비스 프로토콜에 관한 연구)

  • Lee, Jie-Young
    • The Journal of Information Technology
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    • v.9 no.3
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    • pp.59-66
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    • 2006
  • This paper proposes directory service protocol in distributed environment. By adding an condition retrieval function to Modify operation, the ExtModify operation improves the inconvenience to transfer a search operation and resume a Modify operation. The method suggests how to correct all the entries which require retrieval condition out of other entries designated by LDAPND.

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A Study on the Durability of Glass Fiber Reinforced Plastics Rebars (GFRP 리바의 내구성에 관한 연구)

  • Moon, C.K.;Kim, Y.H.;Park, Y.H.
    • Journal of Power System Engineering
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    • v.9 no.2
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    • pp.50-56
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    • 2005
  • The mechanical properties of glass fiber reinforced polymer reinforcing bars(rebar) in various environment conditions such as moisture, chloride, alkali and freeze-thaw actions at temperature ranging from room temperature($25^{\circ}C$) to high temperature of up to $80^{\circ}C$ have been studied. The test results indicated that tensile strength and interfacial shear strength of GFRP bar were decreased with the increasing of temperature and holding time of each environment condition. The degradation in alkali environment. was more serious than those in the other environments.

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