• Title/Summary/Keyword: Medium Barrier

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Analyses on Environment-friendliness of Root Barrier Materials based on Fish Toxicity Test (어독성 실험에 따른 방근재 친환경 특성 분석)

  • Woo, Ji-Keun;Kim, Sung-Kyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.4
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    • pp.42-51
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    • 2010
  • The purpose of this study is to analyze the characteristics of environment-friendliness of Root Barrier materials based on comprehensive experiments on harmfulness of Root Barrier materials and fish toxicity of Oryzias latipes mortality to verify eco-toxicity of each method of construction and Root Barrier material, which are to be applied by taking eco-toxicity into account when building ecological flows in upper areas on natural and artificial grounds. As a result, the following conclusions have been reached in this study: 1. In regard of the harmfulness analyzed, each material showed a different result of analytical value in each lab tank. Compared to lab tank, pH (la), DO (lb), T-N (VI) and T-coli (la) were in the same grade, but COD, SS, T-P and F-coli were less than that of control, respectively increased or decreased by material were analyzed. 2. In the experiment of fish toxicity, Barrier sheet was found to have 66.7% of fish mortality, indicating strong fish toxicity. Synthetic rubber system root barrier sheet (20.0%) was analyzed to have medium fish toxicity, while Synthetic resin system root barrier-waterproof sheet (3.3%), Synthetic rubber system membrane root barrier sheet (3.3%) and Synthetic resin system root barrier sheet (0.0%) showed relatively lower mortality and fish toxicity. To sum up such results as found in the experiment mentioned so far, the values of harmfulness and root penetration resistance analyzed were different in each lab tank, but there was absolutely little correlation with the mortality gained from the experiment on fish toxicity. In the experiment of fish toxicity, environment-friendly root barrier materials were analyzed, and it was found that Synthetic resin system root barrier sheet, Synthetic resin system root barrier waterproof sheet and Synthetic rubber system membrane root barrier sheet are highly environment-friendly. In contrast, Synthetic rubber system root barrier sheet was found to have medium-level environment-friendliness. Also, Barrier sheet was analyzed to have low environment-friendliness.

Study of the Characteristics of Smoke Spread by an Installing Smoke Barrier in Medium Length Road Tunnel (중규모 도로터널의 제연경계벽 설치에 따른 연기확산특성)

  • Baek, Doo-San;Lee, Seung-Chul
    • Fire Science and Engineering
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    • v.30 no.5
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    • pp.9-17
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    • 2016
  • In the case of a medium length road tunnel, the installation of a smoke control facility is not mandatory so users can suffer considerable injuries if a fire breaks out. Therefore, this study analyzed the high-temperature air and toxic gas generated by fire proliferating with time when a smoke barrier is not installed and when the installation interval is 100, 150, 200, and 250 m through 3-dimensional numerical analysis, evacuation simulation, and Quantitative Risk Assessment Methodology targeting the medium length road tunnel. As a result, the diffusion of the high-temperature air and toxic gas occurring from the a fire was delayed when the smoke barrier was installed in a medium length road tunnel compared to that when it was not installed. In addition, when the installation interval of a smoke barrier was 100m and the numerical analysis target was 100m, the diffusion of high-temperature air and toxic gas generated by the fire was delayed more than in the other cases, which was most suitable for tunnel users to evacuate.

The Effect of Fashion Store Service Quality on Perceived Switching Barriers and Store Loyalty (의류점포의 서비스품질이 지각된 전환장벽과 점포충성도에 미치는 영향)

  • 강미연;홍금희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.27 no.8
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    • pp.935-945
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    • 2003
  • This study attempts to understand perceived switching barriers of customers and fashion stores service quality as a core of store loyalty. Medium variations of switching barriers are interpersonal relationships, attractiveness of alternatives and switching costs. Date were collected from 485 subjects who finished their shopping with a self-administered questionnaire. The results were as follows: 1. Classified service quality of clothing stores into 4 ways: VMD of stores or atmosphere, store policy which are involved in store service, sales persons respond and sales persons conviction which are involved in sales service. 2. Service quality of fashion stores is related with switching barrier medium variations. 3. Service quality have an influence on switching barrier medium variations. Its mutual influences increase switching barriers and it gets to be related to the store loyalty. 4. Compared influences of variations to store loyalty between the H department store and the L department store which are research objects. The main difference is that the H department store evaluated personal relationships among service quality, customers and sales persons high compared with the L department store. As the results showed, service quality consists of store service of nonpersonal service area and sales service of personal service. Service quality is related with interpersonal relationships, attractiveness of alternatives and switching costs. It also affects switching barriers and store loyalty.

Transient Global Aphasia with Hemiparesis Following Cerebral Angiography : Relationship to Blood Brain Barrier Disruption

  • Kim, Dong-Ha;Choi, Chang-Hwa;Lee, Jung-Hwan;Lee, Jae-Il
    • Journal of Korean Neurosurgical Society
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    • v.48 no.6
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    • pp.524-527
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    • 2010
  • Temporary disruption of the blood-brain barrier (BBB) after cerebral angiography is presumably caused by nonionic radiographic contrast medium (CM). We hereby report a case of 58-year-old woman who developed decreased mentality, global aphasia and aggravated right hemiparesis after cerebral angiography. Brain CT examination demonstrated gyriform enhancement throughout the left cerebral cortex and thalamus. MR diffusion did not reveal acute infarction. MR angiography did not show any stenosis, spasm or occlusion at the major cerebral vessels. Follow-up CT scan after 1 day did not show any gyriform enhancement. Worsened neurologic signs and symptoms were improved completely after 7 days. In the present study, disruption of the BBB with contrast medium after angiography seems to be the causative factor of transient neurologic deterioration.

A Study on the Medium Facilities in Barrier-Free Certification Evaluation Items (장애물 없는 생활환경 인증 사례를 통한 매개시설 평가항목 분석)

  • Lee, Kyoo-Il;Kim, In-Soon
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.18 no.2
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    • pp.33-43
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    • 2012
  • This study purposes to present the improvement on the index by analyzing concretely the certification and evaluation index and the actual certification acquisition focusing on the buildings acquiring the barrier-free (BF) certification. So, after analyzing the screening results of the buildings acquiring the BF certification and then grasping the general application level based on the above analysis, this study tries to present the improvement on the BF certification index by analyzing the detailed applications of the BF certification-acquired buildings and then grasping the problems on the evaluation index of the current certification system. It was analyzed that the items which applied the BF construction method generalized to the common buildings through the Act on the Promotion of Convenience in medium facilities and the items with higher distribution points were shown as high in terms of points and the acquired point level of items which influenced by the shape and condition of side and land to defile the appearance of buildings were low.

In Situ Bio-barrier Formation using Bacteria/Fungi-Soil Mixture (Bacteria/Fungi 혼합토를 이용한 현장 Bio-barrier 형성)

  • 김건하;송영우;구동영
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03b
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    • pp.489-495
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    • 2000
  • When microorganisms such as bacteria and fungi are injected into porous medium such as soils along with appropriate substrate and nutrients, biomass retained in the soil pore. Soil pore size and shape are varied from the initial condition as a result of biofilm formation, which make hydraulic conductivity reduced. In this research, hydraulic conductivity reduction was measured after microorganism are inoculated and cultured with synthetic substrates and nutrients. Biomass-soil mixture was evaluated its applicability to the field condition as an alternative liner material in landfill by measuring hydraulic conductivity change after repetitive freeze-thaw cycles.

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Bio-barrier Formation by Biomass Injection into Soil (미생물 토양 주입을 통한 Bio-barrier 형성)

  • Kim, Geon-Ha;Song, Youngwoo;Gu, Dongyoung
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.5
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    • pp.927-938
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    • 2000
  • When microorganism is injected into porous medium such as soils along with appropriate substrate and nutrients, biomass retained in the soil pore. Soil pore size and shape are varied from the initial condition as a result of biofilm formation, which make hydraulic conductivity reduced. In this research, hydraulic conductivity reduction was measured after microorganism are inoculated and cultured with synthetic substrates and nutrients. Biomass-soil mixture was evaluated its applicability to the field condition as an alternative liner material in landfill by measuring hydraulic conductivity change after repetitive freeze-thaw cycles. Resistance of biofilm to chemical solution and degree of biodegradation were measured through column test.

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A Study of Impact Factors and Barrier Height of Compact Car Road for Decision of Barrier Type (소형차도로 방호울타리 형식선정을 위한 충돌계수 및 방호울타리 높이선정 연구)

  • Choi, Hyun-Ho;Kim, Ki-Hwan;Lee, Eui-Joon;Yi, Sang-Keun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.6D
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    • pp.605-613
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    • 2010
  • In this study, Impact factors are represented and barrier height of compact car road of safety barrier is suggested through the investigation of applying problems of existed standard of general car road. For this, traffic accidents analysis is performed and based on the analysis, impact vehicle weight, impact Angle, crash velocity, and barrier height are investigated. For the decision of impact angle, analysis is carried out by comparison of RISER and 2-lines expressway accidents data. Through this, higher-impact angle is suggested. Vehicle weight data of sub-compact car, small vehicle, medium and large vehicle, SUV, small truck is surveyed and analyzed. Based on the accident accumulation rate, regression analysis of vehicle weight impact and impact velocity is performed. Also, based on the cumulative rate of vehicle weight on expressways near Seoul, barrier height of compact car road is calculated. It is noted that the results of this study will be contributed to the decision of barrier type.

The characteristic change of water using the wet-plasma (습식 플라즈마에 의한 물의 특성 변화)

  • Lee, Jae-Dong;Park, Hong-Jae;Lee, Dong-Hun;Kim, Young-Ju;Park, Jae-Yoon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.1151-1154
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    • 2003
  • Ultraviolet rays, OH H O radical and $O_3$ produced by the streamer discharge in water are widely used to deactivate microorganisms and remove organic contaminants in water and the dominant factor of these decomposition is the oxidized reaction of hydrogen peroxide and dissolved $O_3$ in water. In this paper, the barrier discharge was used to create plasma in a gas, liquid and solid medium and the electrode with the reactor combined barrier with packed type(BPR) was made as noncontact way against water so that the effect of water characteristic change by the erosion of electrodes exposing in water should be minimized. The active radical and $O_3$ gas generated in plasma region were reacted into the water as electrode so that at the same time a dissolved $O_3$ and hydrogen peroxide were formed in water and The change of pH and conductivity were measured.

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A Study on the Development Strategy for ODM Exporting Company of OEM Exporting Company - Based on the Case Studies - (우리나라 중소 OEM 수출기업의 ODM 수출기업으로의 발전전략에 관한 연구 - 사례분석을 중심으로 -)

  • Kim, Gwi-Ok;Bae, Jung-Han
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.33
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    • pp.311-343
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    • 2007
  • At present, more than 80% export made by Korean small-medium sized companies is OEM(Original Equipment Manufacturing). But OEM export of made-in korea products has been facing limitations from 1990s. Some leading companies among those small-medium sized companies which have been fulfilling OEM export are transferring their exporting strategies to Own Brand or ODM(Original Development/Design Manufacturing) and some of their strategies successful. However, most of small-medium sized OEM exporting companies are still groping for some ways to upgrading to Own Brand or ODM exporting strategies. Therefore, this article deals with how the leading ODM exporting companies have been transferred from OEM to ODM exporting strategies. It also discusses the primary factors of success and barrier and how to develop the ODM exporting strategies based on investigating literature and interviews with the leading ODM exporting companies.

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