نتایج جستجو برای: environmental pollution
تعداد نتایج: 418796 فیلتر نتایج به سال:
background: agate is a hard silica stone with bands of various colors, which is used in jewelry. the agate grinding workers are exposed to silica dust. objective: to determine the prevalence of respiratory diseases in agate grinding workers and the associated factors. methods: in this cross-sectional study, 170 agate grinding workers from mashhad, northeastern iran, were examined. medical and o...
considering the importance of cd and u as pollutants of the environment, this study aims to predict the concentrations of these elements in a stream sediment from the eshtehard region in iran by means of a developed artificial neural network (ann) model. the forward selection (fs) method is used to select the input variables and develop hybrid models by ann. from 45 input candidates, 13 and 14 ...
This pollution accumulation model shows that the environmental absorption capacity is impacted by economic activity. The resulting optimal control problem has two inter-related state variables: the stock of pollution and the absorption capacity of the environment. The stock of pollution decreases with environmental absorption capacity and increases with the rate of current emissions, which is c...
OBJECTIVE To assess the knowledge and perception of parents of high school students about the health effects of environmental hazards in Sakarya province of Turkey. METHOD The cross-section study was conducted in May 2009 in which randomly assigned 362 parents answered a questionnaire inquiring about the sociodemographics and a list of environmental hazards such as tobacco smoking, sunlight e...
The most common method of evaluating beneficial impacts of environmental policies is cost-benefit analysis (CBA). In the present review, CBA methods for air pollution impacts are reviewed. Three types of air pollution effects are identified, including health, productivity, and amenity. Market valuation, stated preference methods, and revealed preference methods are identified for valuing benefi...
By employing the methods of Johansen cointegration test and granger causality test, the paper aimed at investigating the interactions of environmental pollution and economic growth in the process of Zhejiang’s industrialization according to the time series data of three kinds of pollution indices from 1981 to 2006. The results showed that three kinds of pollution indices all had a negative long...
Crane Division, Naval Surface Warfare Center, Crane Crane's comprehensive pollution prevention program emphasizes planning, employee education, innovation and incentives. One of Crane's primary goals is to move the facility from a pollution control mindset to a pollution prevention ethic through its Corporate Environmental Policy Statement, environmental management system and educational tools ...
pricing for an insurance policy can be described as the process of calculation of expectedcompensation to be paid to property losers as well as associated costs of potential risks. loss forecast isaccurate if the risks will be identified appropriately in order to calculate the frequency and expected severityof losses.this is particularly important about environmental risks since most of them ap...
Environmental pollution consists of different types of pollutants in air, soil, and water. Due to the fact that plants can respond to environmental pollution, they can be used as bio-indicators for environmental monitoring. Air pollution in areas with oil and gas refineries nearby is an important problem. This study aims to survey the effects of gas refinery air pollutants on Conocarpus erectus...
background and aims. basic periodontal treatment aims at eliminating supra- and sub-gingival plaque and establishing conditions which will allow effective self-performed plaque control. this aim is primarily achieved with sonic and ultrasonic scalers. however, generation of bacterial aerosols during these procedures is of great concern to patients, the dentist and the dental assistant. the aim ...
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