• Title/Summary/Keyword: harmful environments

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Studies on the Accelerated Aging Characteristics of Paper Records by Gaseous Air Pollutants (가스상 대기오염물질에 의한 종이 기록물의 가속열화 특성 연구)

  • Jeong, So-Yoon;Jeon, Soo-Yeon;Baek, So-Ra;Jeong, Hyun-Seok;Lee, Jin-Hee;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.4
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    • pp.151-159
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    • 2015
  • Paper records were generally degraded by some factors from atmospheric environments, like temperature, relative humidity or air pollutants. In this study, the degradation behavior of paper records by single or mixed gases of $NO_2$, $SO_2$, HCHO and TVOC was evaluated. The mechanical, optical and chemical properties of 4 kinds of paper (acid and neutral-based printing paper, traditional Hanji, and filter paper) were directly and indirectly affected by gaseous harmful materials. The brightness and $L^*$ value in all papers were slightly increased by accelerated aging under gaseous HCHO and TVOCs, but highly decreased by conditions under gases $NO_2$ and $SO_2$. The optical properties of paper records were most vulnerable in acid-based paper and high stable in filter paper and traditional Hanji by air pollutant degradation. The aging treatments under mixed gas pollutants including $NO_2$ resulted in decrease of physical, mechanical and optical properties of paper, so it was supposed that the concentration of $NO_2$ gas would be strictly controlled for optimum indoor air quality management in domestic storage centers for paper records.

Behavioral Characteristics Investigation of Rack Structure Depending on Forklift Impact Scenarios and Storage Distributions (지게차 충돌 위치 및 보관물류 분포에 따른 선반구조물의 거동특성분석)

  • Ok, Seung-Yong;Kwon, Oh-Yong;Paik, Shin Won
    • Journal of the Korean Society of Safety
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    • v.28 no.6
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    • pp.49-56
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    • 2013
  • The statistics of recent accidents in warehouses show that a heavy toll of lives were produced by various accidents, e.g. collision, overturn, fall, slip, exposure to harmful substances or environments, etc. Of significant concern amongst them is the collision, especially the collision between forklift and storage rack structure. Accordingly, this study focuses on behavioral characteristics of rack structure subjected to dynamic impact loading of a forklift. For this purpose, time-domain response analysis has been performed on a standard 2-bay six-story rack structure consisting of columns, beams and bracing members with perforated open section. In order to investigate the most critical scenario, the impact loads are applied in both down-aisle and cross-aisle directions, and the impact locations are also varied along the shelves of the palettes. In order to deal with storage distributions, three types of rack structures are further taken into account: original empty rack structure with no storage, half-loaded rack structure and fully-loaded rack structure. The numerical simulation results demonstrate that the dynamic characteristics of the rack structure are significantly dependent on the distribution of the storage goods and its natural period varies from 0.24sec to 1.06sec, approximately 4.4 times. Further, the parametric studies show that the forklift impact is most critical to the safety of the rack structure when it collides either at the base or at the top of the rack structure.

Postural Risk Assessment of Weed and Kudzu Removal Operations (숲가꾸기를 위한 풀베기와 칡덩굴제거작업의 근골격계 부담 분석)

  • Lee, Eunjai;Baek, Seung-An;Cho, Koo-Hyun
    • Journal of Korean Society of Forest Science
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    • v.109 no.2
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    • pp.195-201
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    • 2020
  • A forest operation is considered as one of the riskiest environments for the development of musculoskeletal disorders because operators are exposed to harmful environmental conditions such as rough terrain, inclement weather, and poor working postures. In weed and kudzu removal operations, manual application is still common in Korea. In this study, we evaluated the ergonomic conditions of weed and kudzu removal in regeneration forests and the associated risk of musculoskeletal disorders. The risk of musculoskeletal disorders was evaluated using the Ovako Working Posture Analysis System and postural risk index. Postural risk was significantly higher for kudzu compared with weed removal operations. This suggests that kudzu removal operations must be improved to decrease postural risk.

Policing for Juvenile Delinquency in Korea (청소년범죄에 대한 경찰활동)

  • Lee, Ha-Sub;Jo, Hyun-Bin
    • The Journal of the Korea Contents Association
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    • v.11 no.7
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    • pp.285-297
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    • 2011
  • At recent years, juvenile crime that occurred, that young people have done incredibly cruel and serious intelligence community is making a serious scandal. The relationship between parents and youth crime under the influence of family environment factors and the hypothetical failure of school maladjustment and school factors due to contact with friends, around the area due to hazardous environment, local surroundings and social factors that committed a crime by were Juvenile crime in the real statistics on the rise again, starting the year 2005, and is increasingly young, violent crimes showed a high percentage increases. In order to prevent juvenile crime, these homes, schools, community work together to raise sustainable alternatives are needed. The police, as well as the maintenance of law and institutions, cooperation of youth organizations, increasing activity, such as removing harmful environmental youth leadership program, the flight needs to be improved. Today, juvenile crime is not simply a matter of police activities, school-linked program, police, community-linked programs, such as police comprehensive preparedness and commitment of the authorities is required.

Environmental Contamination from Acid Mine Drainage (산성광산배수로 인한 환경오염도 조사)

  • Kang, Mee-A
    • The Journal of Engineering Geology
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    • v.17 no.1 s.50
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    • pp.143-150
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    • 2007
  • AMD (Acid mine drainage) from disused mines is one or the most significant pollutant problems to make harmful effect to human health. We demonstrated the mechanism of resolution and adsorption reaction for arsenic, manganese and zink from the soil and mine tailings which were located in the vicinity of a disused mine in Kyoungnam area. The resolution experiments were carried with a column test f3r 45 days continuously. Metal chemical forms in water were changed with the condition of solution pH and ORP (oxidation-reduction potential). Metal chemical forms affected on the reaction of resolution and adsorption of metals in water environments. Even though the sampling was carried in very closed location, there was significant different results of pollution level and ORP changes in terms of column operations. Hence It was important to note the pH and ORP in AMD to evaluate a risk assessment and a soil management using monitoring metals. When we operate AMD management with the mechanism of resolution and adsorption it can be achieved better economic solution.

Isolation and Identification of ${\beta}-Glucuronidase$ producing Clostridium sp. from Fecal Microflora (${\beta}-Glucuronidase$ 생산 인체장내 Clostridium sp.의 분리 . 동정)

  • Park, Jong-Hyun;Shin, Jee-Young
    • Korean Journal of Food Science and Technology
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    • v.31 no.5
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    • pp.1357-1362
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    • 1999
  • For the study of human intestinal environments with the intestinal bacteria producing ${\beta}-glucuronidase\;and \;7{\alpha}-dehydroxylase$, genus Clostridium, known as the producer, were isolated from the fecal microflora. Through screening twice for one person, fecal microflora without major bacterial group seemed to be changed, which indicated the microflora would be changeable by the diet factors. With using Neomycin-Nagler selective medium during the screening, 14 Clostridium spp. were isolated and then the harmful enzyme activities were determined. Isolate-11 among them produced strongly ${\beta}-glucuronidase$ and its activity was 0.021 unit/mg Protein. However, the strain producing $7{\alpha}-dehydroxylase$ was not isolated. The Isolate-11 was tentatively identified as Clostridium scatologenes through cultural and physiological characteristic.

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Development of Environmental-friendly Nontoxic Flame Retardant Paint (친환경 무독성 난연도료 개발연구)

  • Do, Young-Woong;Ha, Jin-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.5
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    • pp.1354-1358
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    • 2008
  • Environmental-friendly nontocxic flame retardant paint which can overcomes the restriction of harmful materials for human body and environments such as Pb, Hg, Cd, $C^{+6}$, PBB/PBDE by EU and domestic Ministry of Environment was developed. Developed paint is the water-soluble organic inorganic hybrid material that VOC(volatility organic compound) discharge is low, and that human riskiness and environmental pollution is minimized not using the kinds of halogen materials. $Mg(OH)_2$, $Sb_{2}O_{3}$, and Zinc borate were used as flame retardant materials, 2% Micell and water were used as binder and solvent, respectively. Results showed the optimum activity was obtained when the ratio of those frame retardant agents($Mg(OH)_2$, $Sb_{2}O_{3}$, Zinc borate made by 1: 2: 2), binder(2% Micell) and water was 1: 0.5: 0.5.

The Utilize V2X about to Autonomous Unmanned Forklift System (자율주행이 가능한 무인지게차 시스템에 대한 V2X 활용)

  • Lee, Jae-Ung;Jang, Jong-wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.05a
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    • pp.229-231
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    • 2018
  • As autonomous vehicle technology has been gradually developed, robots that have introduced autonomous navigation systems have been actively involved in areas where there is a lot of livelihoods such as industrial sites and accident sites. For this reason, the unmanned transportation system equipped with the autonomous traveling system is widely used in harmful environments where human access is difficult. In addition, the introduction of the autonomous driving system reduces the collision and casualties that occur in a mobility environment like the industrial field, and it helps the efficient work process. In addition, autonomous driving vehicles can be handled more safely and quickly in a wider area by transmitting the surrounding environment of each vehicle to a server connected to each autonomous driving vehicle and passing it through the main server. In this paper, by utilizing V2X communication for autonomous unmanned forklift system, it can increase industrial workload, reduce loss of life and damage to property through wide area forklifts.

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Inhibitory effects of the medicinal plant extracts on tyrocinase and elastase, and free radical scavenging effects.

  • Kim, Ik-Soo;Kim, Mi-Jung;Lee, Bock-Soon;Na, Hun-U;Jeon, Jong-Taek;Lee, Hee-Bong
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.820-829
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    • 2003
  • One of the important function of skin is the protection from harmful environments. Many studies were carried out to keep the skin from wrinkling and pigmenting. Skin wrinkle and pigmentation could be caused' by the unusual disruption of connective tissue, the formation of free radicals and the radiation of ultraviolet. In this study, the extracts obtained from 23 different kinds of medicinal plants were examined whether they have inhibitory effect on tyrosinase and elastase as well as free radical scavenging effect. All the extracts examined were obtained by using 70% (v/v) ethanol at $60^{\circ}C$. It has been found that there were two medicinal plants which have positive effects matching with the purpose of this study. The extract of Ephedra sinica stapf shows an inhibitory effect on tyrosinase ($IC_{50}$ = 83.7~$\mu\textrm{g}$/ml), on elastase ($IC_{50}$ = $690{\mu}\textrm{g}$/ml), and also shows free radical scavenging effect ($IC_{50}$ = 29.6$\mu\textrm{g}$/ml). The extract of Betula platyphylla Var. shows an inhibitory effect on elastase ($IC_{50}$ = 498.1$\mu\textrm{g}$/ml), and free radical scavenging effect ($IC_{50}$ = 9$\mu\textrm{g}$/ ml). The aim of the study is to find the natural compounds which have function in skin-lightening, anti-wrinkling and anti-oxidation, with safe and active ingredients in cosmetic.

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Study on occurrence and management of organic micropollutants in sewer systems (국내·외 하수도시설 미량유기물질의 발생 특성 및 관리체계에 대한 이해)

  • Jeong, Dong-Hwan;Ham, Sang-Yee;Lee, Wonseok;Chung, Hyenmi;Kim, Hyunook
    • Journal of Korean Society of Water and Wastewater
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    • v.31 no.6
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    • pp.551-566
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    • 2017
  • As the modern society is rapidly developing and people become affluent in materials, many new chemical compounds in different forms of products (e.g., antibiotics, pesticides, detergents, personal care products and plastic goods) are produced, used, and disposed of to the environments. Some of them are persistently having a harmful impact on the environment and mimicking endocrine properties; in general they are present in the environment at low concentrations, so they are called organic pollutants. These organic micropollutants flow to sewage treatment plants via different routes. In this study, the generation characteristics, exposure pathways, detection levels, and environmental impacts of organic micropollutants were critically reviewed. In addition, currently available risk assessment methods and management systems for the compounds were reviewed. The United States Environmental Protection Agency (US EPA), for example, has monitored organic micropollutants and set the monitoring and management of some of the compounds as a priority. To effectively manage organic micropollutants in sewer systems, therefore, we should first monitor organic micropollutants of potential concern and then make a watch list of specific substances systematically, as described in guidelines on listing water pollutants in industrial wastewater.