• Title/Summary/Keyword: pollution variable

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The Impacts of Heavy Industrial Pollution Sources on The Real Estate Price Evidence from Maanshan City, China (중공업 오염원이 부동산 가격에 대한 미치는 영향 중국 마안산시 중심으로)

  • Wang, Rundong;Zhang, Zhixin;Huang, Shuai
    • The Journal of the Korea Contents Association
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    • v.20 no.6
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    • pp.717-729
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    • 2020
  • As the environmental pollution problem in modern society is rapidly changing with industrialization, the environmental pollution problem has a direct or indirect effect on various fields. In particular, heavy industry pollutants can be a significant variable in site selection and realestate value. Therefore, this study is based on transaction data of 13apartment complexes in Maanshan City, a representative steel city in China, and uses the Hedonic Price Model to study the effect on real estate prices, mainly on heavy industry pollution during environmental pollution. The conclusion shows that the farther away from the source of pollution, the higher values are.

Energy Saving Hydraulic Control System using Hydraulic Pump/Motor

  • Yongrae Cho;Bumseung Oh;Kyoungkwan Ahn;Soonyong Yang;Lee, Byungryong
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.66.1-66
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    • 2002
  • Today it becomes a serious problem to exhaustion of a fossil fuel and air pollution by exhaust gases from road vehicles for environment preservation. To solve this problem, the developments of a hybrid vehicle have been processed for the purpose of reducing pollution and energy-savings. By the way, flywheel hybrid vehicle using variable pump/motor was proposed as one feasible hybrid system in place of hybrid vehicle system by the conventional storage battery. The proposed flywheel hybrid vehicle is composed of an accumulator or a flywheel as the energy generation and storage source and three variable hydraulic pump/motor as the energy transfer device. Flywheel has the characteristic of high...

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A Study on the Energy Saving Hydraulic Control System using Variable Displacement Hydraulic Pump/Motor (가변 유압 펌프/모터를 이용한 유압 제어 시스템의 에너지 절감에 관한 연구)

  • 조용래;안경관
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.9
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    • pp.100-108
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    • 2003
  • This paper proposes a flywheel hybrid vehicle to solve the energy crisis problem by the exhaustion of a fossil fuel and air pollution for the conservation of environment. The proposed flywheel hybrid vehicle is composed of an accumulator and a flywheel as the energy generation and storage component and three variable displacement hydraulic pump/motors as the energy transfer devices. Flywheel has the characteristics of high energy density and easy energy absorption and consumption. The effectiveness of the energy-saving of the proposed flywheel hybrid vehicle is verified by simulation using Matlab/simulink. First of ail, analytical modeling for the flywheel hybrid vehicle is presented and simulations are performed based on the experimental efficiency data of a variable displacement pump/motor. The results of the simulation show that the effect of energy savings is realized by the proposed hybrid vehicle in 3 different city driving patterns.

AC Plasma Power Supply with Variable Voltage and Variable Frequency (가변전압 가변주파수(VVVF) 교류 플라즈마 전원장치)

  • Shin Wan-Ho;Yun Kee-Pok;Jeoung Hwan-Myoung;Choi Jae-Ho
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.1205-1207
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    • 2004
  • AC plasma power supply is used to control a ozone generator and a air pollution gas. AC plasma power supply is composed of power semiconductor switch devices and control board adapted SHE(Selected Harmonic Elimination) PWM method. AC plasma power supply with sinusoidal VVVF(variable voltage and variable frequency) is realized. Its output voltage range is from 0 [V] to 20[kV] and output frequency range is from 8[kHz] to 20[kHz]. Using proposed system, AC high voltage and high frequency discharge is tested in the DBD(dieletric barrier discharge) reactor, and the space distribution of a its non-thermal plasma is observed. In spite of the increasement of voltage and frequency, the proposed system have a stable operation characteristics. It is verified by the experimental results.

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A Time-series Study on Relationship between Visibility as an Indicator of Air Pollution and Daily Respiratory Mortality (대기오염 지표로서의 시정과 일별 호흡기계 사망간의 연관성에 관한 시계열적 연구)

  • Cho, Yong-Sung;Jung, Chang-Hoon;Son, Ji-Young;Chun, Young-Sin;Lee, Jong-Tae
    • Journal of Korean Society for Atmospheric Environment
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    • v.23 no.5
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    • pp.563-574
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    • 2007
  • There seems to be a consensus among most people that visibility impairment is the most obvious indicator of air pollution. While considerable evidence on the association between air pollution and health outcomes including death and disease have been established, based on industrial complex areas or huge urban cities, time-series, case-crossover and cohort studies, scarce literature exists on the direct evidence for the association between visibility and adverse health outcomes. Our study is assessed the effect of air pollution measured by visibility impairment on respiratory mortality over a period of six years. Relative risks in respiratory deaths were estimated by a Poisson regression model of daily deaths between $1999{\sim}2004$. Daily counts of respiratory deaths as dependent variable was modelled with daily 24-hr mean visibility measurements (kilometers) as independent variable by means of Poisson regression. This model is controlled for confounding factors such as day of weeks, weather variables, seasonal variables and $PM_{10}$. The results in this study is observed the statistically significant association between an inverse health effect and visibility during the study period for respiratory mortality (percentage change in the relative risk for all aged -0.57%, 95% Cl, $-1.01%{\sim}-0.12%$; for $0{\sim}15$ aged -7.12%, 95% Cl, $-13.29%{\sim}-0.51%$; for 65+ aged -0.43%, 95% Cl, $-0.93%{\sim}-0.06%$ per 1 km increased in visibility). The effect size was much reduced during warm season. Visibility impairment resulting from air pollution is strongly associated with respiratory mortality, especially for children may be spent at outdoor. Our result provides a quick and useful indicator for eliciting the contribution of air pollution to the excess risk of respiratory mortality in Seoul, Korea.

Environmental Regulations and Korean Trades (환경규제와 한국의 무역)

  • Kim, Il Chung;Choi, Mun Seong
    • Environmental and Resource Economics Review
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    • v.22 no.4
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    • pp.785-815
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    • 2013
  • This paper analyzes the three issues related to the effect of environmental regulations on the Korean trades with gravity equation model: the effect on the Korean exports, the bilateral trade flows between the Korea and the trade partners, and the Korean international competitiveness. For all three issues we carried the empirical tests with fixed effect estimation methods for total industries, non-pollution industries, pollution industries, and also 16 individual pollution industries. We use industry panel data for the 120 largest trading countries with Korea for the years 2000-2010. The Environmental Performance Index (EPI) is used as the proxy variable for the environmental regulation. The empirical result shows that while GDPs of both Korea and its trading partners are very important factors affecting positively the Korean trades for all industries, the environmental regulation of the importing country would be a definite trade barrier to the Korean pollution industries, but not a definite one for the non-pollution industries. In addition, the stricter environmental regulations of Korea's trade partners would weaken the Korean international competitiveness of Korean pollution industries. In this regard, the Porter Hypothesis would have not appeared in the Korean trades of pollution industries during the period observed in this study.

Computation of geographic variables for air pollution prediction models in South Korea

  • Eum, Youngseob;Song, Insang;Kim, Hwan-Cheol;Leem, Jong-Han;Kim, Sun-Young
    • Environmental Analysis Health and Toxicology
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    • v.30
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    • pp.10.1-10.14
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    • 2015
  • Recent cohort studies have relied on exposure prediction models to estimate individual-level air pollution concentrations because individual air pollution measurements are not available for cohort locations. For such prediction models, geographic variables related to pollution sources are important inputs. We demonstrated the computation process of geographic variables mostly recorded in 2010 at regulatory air pollution monitoring sites in South Korea. On the basis of previous studies, we finalized a list of 313 geographic variables related to air pollution sources in eight categories including traffic, demographic characteristics, land use, transportation facilities, physical geography, emissions, vegetation, and altitude. We then obtained data from different sources such as the Statistics Geographic Information Service and Korean Transport Database. After integrating all available data to a single database by matching coordinate systems and converting non-spatial data to spatial data, we computed geographic variables at 294 regulatory monitoring sites in South Korea. The data integration and variable computation were performed by using ArcGIS version 10.2 (ESRI Inc., Redlands, CA, USA). For traffic, we computed the distances to the nearest roads and the sums of road lengths within different sizes of circular buffers. In addition, we calculated the numbers of residents, households, housing buildings, companies, and employees within the buffers. The percentages of areas for different types of land use compared to total areas were calculated within the buffers. For transportation facilities and physical geography, we computed the distances to the closest public transportation depots and the boundary lines. The vegetation index and altitude were estimated at a given location by using satellite data. The summary statistics of geographic variables in Seoul across monitoring sites showed different patterns between urban background and urban roadside sites. This study provided practical knowledge on the computation process of geographic variables in South Korea, which will improve air pollution prediction models and contribute to subsequent health analyses.

Development of a variable resistance-capacitance model with time delay for urea-SCR system

  • Feng, Tan;Lu, Lin
    • Environmental Engineering Research
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    • v.20 no.2
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    • pp.155-161
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    • 2015
  • Experimental research shows that the nitric oxides ($NO_X$) concentration track at the outlet of selective catalytic reduction (SCR) catalyst with a transient variation of Adblue dosage has a time delay and it features a characteristic of resistance-capacitance (RC). The phenomenon brings obstacles to get the simultaneously $NO_X$ expected to be reduced and equi-molar ammonia available to SCR reaction, which finally inhibits $NO_X$ conversion efficiency. Generally, engine loads change frequently, which triggers a rapid changing of Adblue dosage, and it aggravates the air quality that are caused by $NO_X$ emission and ammonia slip. In order to increase the conversion efficiency of $NO_X$ and avoid secondary pollution, the paper gives a comprehensive analysis of the SCR system and tells readers the key factors that affect time delay and RC characteristics. Accordingly, a map of time delay is established and a solution method for time constant and proportional constant is carried out. Finally, the paper accurately describes the input-output state relation of SCR system by using "variable RC model with time delay". The model can be used for a real-time correction of Adblue dosage, which can increase the conversion efficiency of $NO_X$ in SCR system and avoid secondary pollution forming. Obviously, the results of the work discover an avenue for the SCR control strategy.