• Title/Summary/Keyword: harmful environment

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Performance of Concrete in Aggressive Environment

  • Aguiar, Jose B.;Camoes, Aires;Moreira, Pedro M.
    • International Journal of Concrete Structures and Materials
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    • v.2 no.1
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    • pp.21-25
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    • 2008
  • Surface treatments act as a barrier between the environment and the concrete, preventing or retarding the entry of harmful substances and cutting off the transportation path into concrete. The effectiveness of a surface protection preventing the permeation depends on how close and strongly connected are the resin molecules. This work intends to contribute to a better understanding of the performance of protected concrete in chemically aggressive environments, by presenting results of ion diffusion and resistance to aggressive solutions of several hydrophobic agents and coatings used to protect concrete. Three different types of surface protections were tested: silicone hydrophobic agent, acrylic and epoxy coatings. The obtained results indicate that the overall performance of epoxy resin was better than the other selected types of protections.

Dirt Roads vs. High Speed Train: Opinion Towards ROI Value of Thailand's Transportation Infrastructure Development

  • Boonwattanopas, Nattawadee
    • Asian Journal for Public Opinion Research
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    • v.3 no.1
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    • pp.22-39
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    • 2015
  • This research is a qualitative based study by using data gleaned from documentary analysis and in-depth interviews of 10 potential stakeholders were involved in the proposed high-speed train project in Thailand. Many perspectives from key informants revealed that this project would bring Thailand sustainable development in the future due to the fact that it is supposed to be an environmentally friendly mode of transportation and timesaving for passengers. Key informants who tend to have negative opinions towards the project feel apprehension due to the huge monetary investment during a time of monetary crisis. However, there was one complaint that the high-speed train is harmful to the environment surrounding the proposed area of this project. Several key informants agreed that ticket fares must be in between the cost of a bus ticket and airfare.

살균과 탈취를 위한 오존 발생장치의 설계

  • Kim, Hyeon-Jong;Yun, Yeong-Mi;Han, Ji-Hye;Kim, Yeong-Ran;Lee, Eun-Mi;Lee, Hyeon-Cheol;Jeong, Bong-U
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.509-512
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    • 2001
  • Recently, our country's piggery has been becoming large-sized and crowded gradually in scale. Thus, the environment in a piggery is getting worse, which leads to a drop in livestock's immunoactivity. Therefore, livestocks are exposured to many diseases(stress, hypertension, stomach ulcer etc.). In this paper, our intention is to design a low cost ozone-generating device with high capacity to maintain a reasonable ozone level, that is necessary for cleaning the environment in a piggery, but is not too high to cause any harmful influence to human beings and livestock. The results showed that the UV-lamp tube with baffle has an increase of 25% in ozone generation efficiency compared to without baffle and the short retention time of air or high inlet air rate shows high level of ozone.

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Physical properties of chitosan added on acrylic acid grafted cotton fabrics (아크릴산 그라프트 중합시 첨가된 Chitosan이 면직물에 미치는 물성)

  • 김수미;송화순
    • Textile Coloration and Finishing
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    • v.14 no.6
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    • pp.313-318
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    • 2002
  • Chitosan is known to be an excellent biocompatible natural polymer. Recently, with a growing interest of health and environment, chitosan which is good in no harmful effect on human body and environment, has been watched as the finish treatment of hygiene and pleasantness. The purpose of this study is to develop multi functional fabrics by chitosan added on acrylic acid grafted cotton fabrics. Therefore physical properties such as moisture regain, air permeability, whiteness, static voltage and tensile strength of chitosan added on acrylic acid grafted cotton fabrics were investigated. The results are as follows ; According to increased chitosan's concentration, grafting yield was decreased. Therefore thickness of film by treated chitosan added on acrylic acid grafted cotton fabric became thin. FT R spectra of chitosan add on acrylic acid grafted cotton fabric clearly showed peaks of COOH and $NH_2$, Moisture regain, static voltage of chitosan add on acrylic acid grafted cotton fabrics were increased than control. Air permeability, whiteness and tensile strength were decreased than control.

An Experimental Study on Application of Biodiesel Fuel in Direct Injection Diesel Engine (직접 분사식 디젤기관에서 바이오디젤유의 적용에 관한 실험적 연구)

  • Oh, Y.I.;Choi, S.H.
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.818-823
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    • 2001
  • Because the exhaust emissions from automobiles are increased, our environment is faced with very serious problems related to the air pollution in these days. In particular, the exhaust emissions of diesel engine are recognized main cause which influenced environment strong. Lots of researcher have been attempted to develop various alternative fuel on purpose to reduce these harmful emissions. In this study, the potential possibility of esterfied rice bran oil which is a kind of biodiesel fuel was investigated as an alternative fuel for diesel engine. And, we tried to analysis not only total hydrocarbon but hydrocarbon components from $C_1$ to $C_6$ in exhaust gas using gas chromatography to seek the reason for remarkable reduction of exhaust emission. Individual hydrocarbon$(C_1\simC_6)$ as well as total hydrocarbon of biodiesel fuel is reduced remarkably than that of diesel fuel in this experiment.

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A Study on the Design of Filter Assembly Automation System (Filter 조립 자동화 시스템 설계에 관한 연구)

  • Kim, Hong-Gun
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.6
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    • pp.111-117
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    • 2008
  • An automation process of filter unit is presented for the application of the assembling procedure and dry furnace work. By that automation procedure, it is expected to enhance working environment such as reducing laboring load, harmful gas, and burning scald. Furthermore, this automation process also minimizes via standardization of manufacturing process so that it may increase productivity and reliability. An automation process of filter unit is presented for the application of the assembling procedure and dry furnace work. Filter automation process also gives a good quality and productivity by simplifying to only one line from the complicated process such as filter cutting$\rightarrow$ adhering$\rightarrow$fabricating in a very small space. It is found that a new conceptual design of dry furnace shows the better quality like uniform heat distribution compared to the conventional design. It is also found that the present design gives a better working environment by adding cooling system.

Treatment of Ballast Water By Filtration -Ultraviolet radiation-Electrolytic Process (FUE 공정에 의한 Ballast Water처리)

  • 박상호;김억조;박성진;김인수
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.8 no.2
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    • pp.23-27
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    • 2002
  • Reballasting at sea, as recommended by the IMO guidelines, currently provides the best-available measure to reduce the risk of transfer of harmful aquatic organisms, but is subject to serious ship-safety limits. It is therefore extremely important that alternative, effective ballast water management and treatment methods are developed as soon as possible, to replace reballasting at sea. Filtration-Ultraviolet radiation-Electrolytic process (FUE) was evaluated for disinfection of seawater used In ballast water Optimal current density and UV light intensity were 2.0A/dm$^2$ and, 220㎼/$\textrm{cm}^2$/m with which 100% reduction time was 2sec in a Ultraviolet radiation-Electrolytic process. This study showed that FUE process was effective for the disinfection of commonly isolated bacteria and bacillus from ballast water.

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A noncontact distance and dimension measurement system for remote handling in hostile environment (극한환경 원격조작을 위한 거리측정시스템 개발)

  • 정우태;이재설;박현수
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.602-607
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    • 1990
  • Spent nuclear fuel is very dangerous substance emitting strong ionizing radiation which is harmful to human body. The remote handling of spent nuclear fuel is essential because people cannot access this substance without protecting radiation. To handle highly radioactive material or nuclear waste, many kinds of teleoperators such as master slave manipulator, electro mechanical manipulator, servo manipulator, mobile robot was developed. The distance and dimension of target object cannot be measured easily when highly radioactive material is handled by teleoperator because one should use lead glass or TV camera and monitor to protect radiation and see target object. During experiments on the remote handling of spent nuclear fuel by electro mechanical manipulator, we often felt that a distance and dimension measurement system is necessary to handle the objects which is in the highly radioactive environment, so we developed a system which is appropriate for this purpose.

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Study on comparisons between PSS/E and Matlab Simulink/SimPower Result on network system data (PSS/E - Matlab Simulink/SimPower 간 순시치 시뮬레이션 비교에 관한 연구)

  • Yoo, Yeuntae;Kim, Kisuk;Lee, Changun;Jang, Gilsoo
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.249-250
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    • 2015
  • Technological advance of power elcetronic devices using semiconductor switches in last several decades, invoke the increase of switching devices' penetration in the system like STATCOM or HVDC and also, increase the difficulty to adjust switching characteristics in the virtual simulating configuration, which are not capable of reflect the detailed phenomena. To investigate harmful effect of switching devices into the grid, detailed modeling of power electronic devices are necessary, and the first step for entire grid modelling is simulate power system in time domain model. In this paper, simple two bus system with synchronous generator and infinite bus on the other side has been compromised in two simulation environment, using PSS/E and Matlab/Simulink. Comparing the result of two simulation result will give answers to the fundamental difference between two type of simulation environment.

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IKEA and Corporate Social Responsibility: A Case Study

  • Hahn, Yoonah
    • Journal of Distribution Science
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    • v.13 no.10
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    • pp.45-50
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    • 2015
  • Purpose - The purpose of this paper is to examine IKEA in the context of corporate social responsibility to determine the reasons, if any, as to why IKEA has had more success in the implementation of its CSR policies and Code of Conduct where many other multinational companies seem to have failed. Research Design and Methodology - This is a case study, an analytical approach, which focuses on exploring and analyzing the CSR policies to measure IKEA's ethical behavior in a business environment. Results - IKEA stands out as a multinational company whose CSR policies are ingrained into the business itself as a part of its ethical operations, rather than a marketing event. Conclusion - Beyond profit, IKEA actively works together with its suppliers and the nation states to eradicate the harmful social causes of the various challenges it faces in the global business environment.