• Title/Summary/Keyword: 환경공해

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Theoretical study on rock excavation method by whitelight thermal stress (백열광을 이용한 무진동, 무소음 암반파쇄공법의 이론적 고찰)

  • Choi, Yong-Ki;Han, Hyun-Hee;Kim, Sung-Hwan;Kim, Hak-Joon;Arrison, Norman L.;Kong, Hoon-Joo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.4 no.3
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    • pp.229-234
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    • 2002
  • Nowadays, the blast method is mainly operated in the fields of the rock excavation accompanied by construction site in Korea. Blast method has many merits such as improvement of workability, reducement of operation period, and etc. However, blast operation also create much loss and troubles with the neighbours for the environmental pollutions such as the noise, blast vibration, fly rocks and dusts. Thus, the non-vibration and shallow vibration methods have been used but they have also another problems in the view of the economy and the efficiency in operation. In this study, we had made laboratory tests for the breaking of the various Rock types by White Light Thermal Stress. The tests shows that one unit consuming 500kilowatts of electricity, would go 90 feet a day in tunneling if the tunnel was 16 feet by 16 feet. Also, if a faster rate of tunneling could be handled, other white light units could be added.

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The Establishment and Transformation of the Mountain Fortress Town of Kwangju County in Kyonggi Province (산성취락연구(山城聚落硏究) : 남한산성(南漢山城) 광주읍치(廣州邑治)의 형성(形成)과 쇠퇴(衰退))

  • Hong, Keum-Soo
    • Journal of the Korean association of regional geographers
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    • v.10 no.2
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    • pp.313-340
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    • 2004
  • Namhansan fortress of Kwangju in Kyonggi Province has remained a traumatic historical landscape of Manchu invasion in the year 1636. Skirted by the mountain fortress and on the ground of the uplifted flatland was the county seat which was relocated in 16Z7 from Kogol at the underneath ravine and later removed in 1917 to a crossroad place at the low-lying river plain. Once a secluded mountain village, Sungnaedong was at the outset planned as a county town of Kwangju, achieving thereafter a dramatic transformation from a small town of three hundred households into a nascent urban settlement of approximately six hundred households by the mid-18th century. The townscape of Sungnaedong features shrines, a second palace, a magistrate-commander's office, administrative buildings, and a periodic marketplace which were all decreed by the Neo-confucian template of the scheme of county seats. Townspeople managed to live on tilling tax-alleviated crop lands, trading merchandise, and selling their labor. Changing socio-economic situations led to the relocation of the administration center to the gateway village of Jumakri, which consequently heralded the decline of the mountain-fortress settlement of Sansungri at Namhansan.

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Development and Analysis of Non-Urban region Traffic Safety Facilities Considering Economics (경제성을 고려한 비도심 지역 교통안전 시설물의 개발과 분석)

  • Kim, Ki-Nam;Lee, Yong-Jun;Lee, Dong-Yeol;Cho, Choong-Yuen;Lee, Min-Jae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.577-586
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    • 2018
  • In this study, traffic safety technology was developed for rural areas by reviewingthe relevant literature and data from the Traffic Accident Analysis System for the Chungcheong region.The goal is to reduce traffic accidents in small regional cities and rural areas in Korea. A road shoulder recognition light was developed to fit the pedestrian characteristics of the people using transportation in rural areas. It also minimizes damage to crops due to light pollution from traffic lights and street lights, and it supplements problems of damage from collision with vehicles and agricultural machines. The efficiency of the technology developed in this study was verified by comparing and analyzing the number of traffic accidents and the saved cost before and after its installation. A test bedwas established based on rural areas and is being evaluated for its applicability and effectiveness. It is expected that the reliability of such facilities could be improved through continuous studies, data collection, and analysis.

Output Characteristics of Small Wind Power Generator Applying Multi-Layered Blade (다층형 블레이드를 적용한 소형 풍력발전기의 출력특성)

  • Lee, Min-Gu;Park, Wal-Seo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.663-667
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    • 2017
  • Fuel depletion and environmental problems due to the use of fossil fuels have been worsening of late, and the development of alternative energy sources is urgently required to address these problems. Among the alternative energy sources, wind energy is attracting much attention as a clean energy source, because it can be used unlimitedly without any pollutant emissions. In wind power generation, wind energy is converted to kinetic energy through rotor blades and this kinetic energy is converted to electric energy through generators. The design and manufacturing of the blades, which are the major parts of wind power generators, are very important, but South Korea still lacks the requisite basic data and key technologies and, therefore, has to import the blades from overseas. In this study, multi-layered blades capable of generating power at low wind speeds were applied to a small wind power generator and the output characteristics of the generator according to the wind speed and the number of blades were analyzed. As a result, at the maximum wind speed of 8m/s, the application of three blades achieved up to 33% and 18% higher generator output voltage, up to 33% and 15% higher generator output current, and up to 23% and 13% higher generator RPM than the application of one or two blades, respectively. In this study, the application of multi-layered blades to a small wind power generator was shown to improve the output characteristics of the generator and make the collection of electric energy possible even at low wind speeds.

The Study on the optimized LED module of VMS for saving energy (에너지 절감을 위한 VMS LED 모듈 최적화 연구)

  • Kim, Young-Rok;Lee, Suk-Ki
    • International Journal of Highway Engineering
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    • v.13 no.4
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    • pp.231-238
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    • 2011
  • Variable message signs(VMS) in use are being displaying with the LED device as the luminous source, and it is a recent trend to be changed from the Lamp type to the Surface-Mount Devices(SMD) type. The LED device leads to get VMS display brightly and clearly, leading to have visibility and legibility better than the existing VMS. However, the lights which display off the road, the unnecessary energy, might have negative effect on ecosystem. This study developed the way of getting the lights be displayed only to drivers without the unnecessary energy and estimated the energy efficiency of the development by the optical testing. As a result, this study showed that the energy consumption of the developed display device appeared to decrease by about 36.1% compared to the existing device. Also the upward and downward angle of the lights changed from an angle of $24^{\circ}C$ to $0^{\circ}C$and from an angle of $-24^{\circ}C$ to $-11^{\circ}C$, respectively. Therefore, it anticipates that the developed device would benefit highway safety due to an improvement in visibility and legibility compared to the existing VMS and the energy consumption would be less lower than the existing VMS.

Utilization of Industrial Wastes for Organic Fertilizer Use (유기질비료(有機質肥料) 자원(資源)으로서의 산업폐기물(産業廢棄物))

  • Han, Ki-Hak
    • Korean Journal of Soil Science and Fertilizer
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    • v.11 no.3
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    • pp.195-206
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    • 1979
  • Where the industrial waste is increasing in number of kind and in quantities by the industrialization and population increases, the pollution problem is not only national but grobal question of the day. This paper is trying to invite attentions by the people who are working in both sector-natural sciences and industries in reviewing limited reports and materials. 1. By the chemical evaluation of over 20 industrial waste produced in Korea, potential wastes for commercial fertilizer would be wastes from alcohol fermantation, beer brewery, leather processing, synthetic fiber, and coffee grounds. 2. The composition of city waste is differ from other countries and sludge cake from human feces processing is promising one in the organic matter and phosphate content particularly. However, the content of heavy matals, specific order, and availability of phosphate are the bottle-neck for the development. 3. There is one commercial fertilizer from industrial waste in the market. It is very reasonable in the content of nitrogen and organic matter, and its formulation and responeses on crops. 4. Discussions were also given on the general problems in processing and marketing of fertilizers from industrial waste, however, scientists and industrial owners have to pay more attention on the development of fertilizers from tire industrial wastes because of vital environmental protection view-point.

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Effect of Coating Materials for Steel on the Threshold of Corrosive Amount of Airborne Chlorides and the Evaluation of Their Corrosion Speeds (강재마감별 부식개시 임계 비래염분량 및 부식속도 평가)

  • Cho, Gyu-Hwan;Lim, Myung-Hyun;Park, Dong-Cheon
    • Journal of the Korea Institute of Building Construction
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    • v.15 no.2
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    • pp.143-151
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    • 2015
  • Many studies have investigated the airborne chlorides that can weaken the overall durability of the concrete structures due to the corrosion of steel materials, but most of the studies have aimed to examine weathering by exposing various construction materials to the actual oceanic environment. However, with the exposure test, it was difficult to find the threshold of precise corrosive amount of airborne chlorides due to diverse deteriorating environmental factors such as ultraviolet ray, acid rain, floating material from industrial pollution as well as airborne chlorides. Therefore, in this study, an airborne chloride simulator was set up, in oder to conduct a corrosion accelerating test for steels coated by five different finishing materials. As results, it was found that the corrosion began to be observed at $0.58{\sim}0.73mg/dm^2$ for no-coated steel, at $7.89{\sim}8.46mg/dm^2$for urethane-coated steel, at $57.95{\sim}69.48mg/dm^2$ for red lead-coated steel, and at $80.73{\sim}89.35mg/dm^2$ for stainless-coated steel, respectively. Hence, these specific data can be considered as the threshold ranges of corrosion for each coating material for steel.

The Significance of p53 Expression in Serum and Tissue from Patients with Lung Cancer (원발성 폐암환자의 혈청 및 조직에서의 p53단백 표현)

  • Chang, Jung-Hyun;Sung, Sun-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.333-340
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    • 1998
  • Background: Lung cancer is the leading cause of cancer over the world. P53 alteration is by far the most common genetic defect in lung cancer. The mutation of p53 protein involves the loss of inhibitory function of p53 related tumor suppressor gene and resultant oncogenesis. The analysis of p53 alterations consists of immunohistochemical stain, PCR based assay, or serologic ELISA (enzyme-linked immunosorbent assay). Methods : Serum levels of p53 mutant protein were measured in 69 cases of lung cancer (adenocarcinoma n=29, epidermoid n=16, small cell n=13, large cell n=1, undifferentiated n=1, undetermined n=9) and 42 controls of respiratory disorders using ELISA. Immunohistochemical stain in tissue was performed using monoclonal antibody of p53 in lung cancer subjects. Results: Both serum p53s in nonsmall cell cancer ($0.28{\pm}0.44ng/ml$) and in small cell cancer ($0.20{\pm}0.14ng/ml$) were not different from controls ($0.34{\pm}0.20ng/ml$). Also there was no significant difference in serum p53 according to tumor stages. P53 immunohistochemical stain showed 50% positivity overall in lung cancer. There were no close correlation between serologic level and positivity of immunohistochemical stain. Conclusion: The serologic determination of p53 mutant protein is thought to have no diagnostic role in lung cancer. Immunohistochemical stain in lung cancer specimen shows 50% positivity.

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Quaternary Diatom Assemblages from Sediment Core GC 98-06 in the Southern Drake Passage, Antarctica (드레이크 해협 남부 코어퇴적물에서 산출된 제 4기 규조 화석 연구)

  • Lee, Jong-Deock;Yoon, Ho-Il;Yun, Hye-su;Kim, Hyo-Jeong;Bak, Young-Suk
    • Journal of the Korean earth science society
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    • v.23 no.5
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    • pp.442-453
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    • 2002
  • A total of 64 species belonging to 23 genera of diatom fossils are identified from the Core GC 98-06 in the southern Drake Passage, Antarctica. The diatom assemblages are dominated by Actinocyclus actinochilus, Coscinodiscus asteromphalus, Eucampia antarctica, Fragilariopsis kerguelensis, Thalassiosira lentiginosa, T. ritscheri and T. anguste-lineata, which are about 73% of the assemblage. Open water species are more abundant than sea ice species in the diatom assemblages of the core. Fragilariopsis. kerguelensis and Thalassiosira lentiginosa are valuable indicators of the habitats. Especially, F. kerguelensis represent the influence of waters from the Antarctic Circumpolar Current. Sea ice taxa represents the influence of cold waters from Bransfield Strait Water and melt water from the sea-ice at during warm periods. The reworked diatoms such as Denticulopsis dimopha (Miocene) and D. hustedtii (Pliocene) are occurred with Quaternary species (Actinocyclus actinochilus, Fragilariopsis kerguelensis, Thalassiosira lentiginosa, and T. glacilis). The presence of reworked diatoms indicates the transportation of the older diatoms into the Drake passage from the circumference sediments, due to strong bottom current activity of Antarctic circumpolar deep water.

The implementation of sign design simulation software (사인디자인 제작 체험 시뮬레이션 소프트웨어 개발)

  • Paik, Jin-Kyung;Lee, Kyung-Mi;Yeoun, Myeong-Heum
    • Archives of design research
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    • v.19 no.2 s.64
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    • pp.163-172
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    • 2006
  • Sign is one of the important factors in city and national image formation, thus requires high level of quality. However, domestic sign emphasize only the sense of attention that leads to big sized signs, thus often results in a poor coordination with the surrounding space. This situation requires employees in sign business want to learn specialized knowledge about design field. Based on these circumstances, we propose sign design software to employees in sign business field as an aid tool that can help to develop good signs in terms of functionality as well as harmony of design. Thus, in this investigation, sign simulation software application case that can design sign and apply this sign to the actual application site is presented. In order to develop this software, literature survey and preliminary studies were performed to analyze the preparation process and environment, and designed sign design element and software elements, user interrace, and finally Java software were utilized. This developed software can be used as a textbook in sign design related departments in schools, and hopefully to enhance the social recognition of sign as well as academic interest.

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