• 제목/요약/키워드: concern levels

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Differential regulation of phospho-p38 and phospho-ERK by TCDD

  • Kim, Ho-jun;Cho, Sung-whan;Son, Hwa-young;Yoon, Won-kee;Jeong, Kyung-shik;Ryu, Si-yun
    • 한국수의병리학회:학술대회논문집
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    • 한국수의병리학회 2003년도 추계학술대회초록집
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    • pp.42-42
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    • 2003
  • The contamination of the environment with pollutants is one of the main problems of modern life, and the levels pollution in industrialized regions are giving raise to increased public concern. The mitogen-activated protein kinase (MAP kinase) are playa pivotal role in the regulation of important cellular functions by activation of specific signal transduction pathways from cell the surface to the nuclei. Three major subgroups of MAP kinases have been identified, and these comprise the extracellular signal-regulated kinase (ERK), the c-Jun amino-terminal kinase (JNK), and the p38 MAP kinases [1-3]. Herein, we investigated the effect of regulation of phospho-JNK (p-JNK), phospho-p38 (p-p38) and phospho-ERK (p-ERK) by TCDD. (omitted)

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Influence of Exposed Aggregate Texturing on the Reducing Traffic Noise Emission

  • Han-Young, Moon;Sang-Wook, Ha;Eun-Cheol, Yang
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.1067-1070
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    • 2003
  • The effects of traffic noise are a serious concern in many urban communities throughout the world. Environmental noise at high intensities directly affects human health by causing hearing loss and indirectly affects human welfare by interfering with sleep, thought, and conversation. In general, portland cement concrete(PCC) pavement is known to create more noise than asphaltic surfaces though it has the advantage of durability and superior surface. However, the results of preliminary laboratory test showed exposed aggregate concrete(EAC) have an effect on reducing traffic noise. Based on the laboratory test, pilot construction of exposed aggregate concrete was performed and series of in-situ measurements were conducted for noise analysis which included the pass-by noise measurement and the close-proximity method. Conclusively, It is expected that tire/pavement noise which is represented much noise levels at higher frequencies would be significantly reduced on special textures of pavement as like exposed aggregate concrete.

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Immunoassay for Monitoring Pesticide Contamination in Agricultural Products

  • Park, Eun-Kee;Lee, Hu-Jang
    • 한국환경보건학회지
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    • 제34권6호
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    • pp.433-438
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    • 2008
  • Much of the increase in agricultural productivity over the past half century has been due to the control of the pests with synthetic pesticides. The use of these pesticides has caused environmental problems and public health concern. The guidelines of maximum residue levels of pesticides in agricultural products has been well documented but more careful monitoring of their residues is required. Pyrethorid class pesticides are dominant in modern agricultural industry but public health concerns have been recently considered. The major route of pesticide exposure is the diet and with improved surveillance of pyrethorid residues in agricultural products their exposure should be controlled and minimized. In suitable products with reduced matrix effects such as agricultural products, aqueous samples, fruits and vegetables the use of immunoassays for pyrethorid residue monitoring could satisfy this requirement. Immunoassays have several advantages, namely they are highly sensitive, selective and cost-effective and enable large-scale sample handling and analysis in the laboratory.

A Conceptual Model of Port Clusters and Related Assemblages

  • Roh Hong-Seung
    • 한국항해항만학회지
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    • 제30권2호
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    • pp.145-150
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    • 2006
  • Recently we have seen a noticeable trend in ports to establish port clusters. Despite this trend, little research has actually been undertaken to fully define and analyse port clusters. A couple of exceptions have descriptively defined port clusters but the boundaries of port clusters are not apparent. Therefore, the aim of this paper is to define port clusters in terms of set theory and in particular look at them in terms of their distinct characteristics and system boundaries. The main concern of this paper is that there is a need to distinguish, from a system and a competition perspective, between port clusters, ports, maritime clusters and port ranges. This paper proposes a conceptual model relevant to the relationship among port clusters related assemblages and that has been applied to the north western europe region This model suggests six levels of competition that will help port authorities and government to develop appropriate policies and strategies for port operation and port industry.

Managing Soil Contamination in the United States: Policy and Practice

  • Small, Matthew C.
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 International Symposium
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    • pp.58-69
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    • 2003
  • Soil contamination in the United States is managed using a risk-based decision making process. In other words, we don't ask, 'how much soil contamination can be cleaned up\ulcorner' Instead we ask, 'how much contamination can be safely left in place\ulcorner' The determination of 'safe' levels of contamination is based upon the potential for exposure and the toxicity of the contaminants of concern in soil. Potential for exposure is determined by evaluating potential exposure pathways from source to receptor given current or reasonably anticipated land use. Soil cleanup goals are then calculated for any complete exposure pathways based upon toxicity and the route of exposure. In some cases, institutional or engineering controls are also used to limit the potential for exposure. In order to prevent a continuous degradation of environmental quality, risk-based cleanup approaches must be combined with strong contamination prevention programs. In addition, alternative risk management approaches should be incorporated into an overall risk reduction strategy.erall risk reduction strategy.

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엔진속도와 부하가 디젤 배기가스에 미치는 영향에 관한 연구 (A study of the effects of engine speed and load on diesel emissions)

  • 이재순;김승무;서정일
    • 오토저널
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    • 제4권2호
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    • pp.47-57
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    • 1982
  • Smoke, Hydrocarbon and Garbon Monoxide emissions of concern in environmental pollution on AVDS-170-2D diesel engine were studied experimentally and past studies on emissions of diesel engine were investigate. Engine speed and load were considered as variable factors influencing the emissions. The test results of a multicylinder, direct injection and turblcharged 4 cycle diesel engine were compared with past studies. Both emission levels of experimental study and past studies were markedly influenced by engine operation factors. The results obtained in this study can be summarized as follows; 1) Smoke intensity is proportional to engine load and varies with engine speed. 2) Hydrocarbon and nitric oxides emissions vary with engine speed and load. 3) Garbon monoxide emission is insensitive to engine speed and varies with engine load.

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Cadmium Exposure and Potential Health Risk from Foods in Contaminated Area, Thailand

  • Chunhabundit, Rodjana
    • Toxicological Research
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    • 제32권1호
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    • pp.65-72
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    • 2016
  • Man-made cadmium (Cd) emissions can be transported between environmental matrices and the food chain. Food is the primary source of Cd exposure among general population as a consequence of the bioconcentration of Cd from soil. Chronic Cd exposure has been reported to be associated with chronic kidney disease, osteoporosis, diabetes, cardiovascular disease and cancer. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) established the safe level of Cd intake as provisional tolerable monthly intake (PTMI) of $25{\mu}g/kg\;bw$ in 2010. The major food groups that contribute to the most Cd exposure are rice and grains, shellfish and sea food, meat including edible offal, and vegetables. A number of studies reported the high Cd contaminated levels in foods from polluted areas in Thailand. The results are of high concern since the contaminations occur in foods that are major Cd contributors. Thus, in this review, the current situations of Cd contaminated foods in polluted areas of Thailand are summarized. In addition, the Cd intakes from selected scenarios are estimated to assess the potential health risk to consumers and the suggestions are also included.

항공교통관제사의 피로.스트레스 요인 (Fatigue and Stress of Air Traffic Controllers in Korea)

  • 윤용식;이수란;손영우
    • 한국항공운항학회지
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    • 제20권1호
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    • pp.76-85
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    • 2012
  • Air traffic controllers often experience fatigue and stress on the job due to work-related factors. Performance impairment resulting from fatigue and stress is an important concern for aviation safety. The goal of this research was to investigate fatigue and stress factors for air traffic controllers. The research involved an extensive literature review of fatigue and stress in the air traffic control environment and surveyed fatigue and job stress level of Korean air traffic controllers compared to other occupation groups. Results of survey showed that fatigue and stress levels of air traffic controllers were significantly higher than other occupation groups. Specially air traffic controllers reported that night work created high level of fatigue and perceived that physical environment and job demand induced high level of stress. In addition, implications for fatigue and stress management were discussed.

A Structural Engineer's Approach to Differential Vertical Shortening in Tall Buildings

  • Matar, Sami S.;Faschan, William J.
    • 국제초고층학회논문집
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    • 제6권1호
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    • pp.73-82
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    • 2017
  • Vertical shortening in tall buildings would be of little concern if all vertical elements shortened evenly. However, vertical elements such as walls and columns may shorten different amounts due to different service axial stress levels. With height, the differential shortening may become significant and impact the strength design and serviceability of the building. Sometimes column transfers or other vertical structural irregularities may cause differential shortening. If differential shortening is not addressed properly, it can impact the serviceability of the building. This paper takes the perspective of a structural engineer in planning the design, predicting the shortening and its effects, and communicating the information to the contractor.

다구찌 방법을 이용한 폴리아세탈 수지 절삭조건 결정 (An Optimal Parameter Design of Polyacetal Resin Cutting Experiment Using Taguchi Method)

  • 조용욱;박명규;김희남
    • 대한안전경영과학회지
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    • 제3권1호
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    • pp.117-125
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    • 2001
  • Polyacetal resin is usually used to make molds, but it is difficult to achieve dimension accuracy during molding. Therefore it is usually necessary to cut the polyacetal resin after a molding process. Polyacetal resin is easily machining by standard machine tool. Acetal is also a thermal stable material which can be totted without coolant Another concern about the use of polyacetal resin is that it absorbs water easily, which also results in problems with dimension accuracy Therefore, in this study, the cutting resistance of water-absorbed polyacetal resin and its surface roughness after cutting in order to achieve the highest degree of accuracy in the cutting of polyacetal resin were investigated. Also, The Robust Design method uses a mathematical tool called orthogonal arrays to study a large number of decision variables with a small number of experiments. It also uses a new measure of quality, called signal-to-noise (S/N) ratio, to predict the quality from the customer's perspective. Thus, we have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.

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