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21.
With the advancement of computational systems and the development of model integration concepts, complexity of environmental model systems increased. In contrast to that, theory and knowledge about > environmental systems as well as the capability for environmental systems analyses remained, to a large extent, unchanged. As a consequence, model conceptualization, data gathering, and validation, have faced new challenges that hardly can be tackled by modellers alone. In this discourse-like review, we argue that modelling with reliable simulations of human-environmental interactions necessitate linking modelling and simulation research much stronger to science fields such as landscape ecology, community ecology, eco-hydrology, etc. It thus becomes more and more important to identify the adequate degree of complexity in environmental models (which is not only a technical or methodological question), to ensure data availability, and to test model performance. Even equally important, providing problem specific answers to environmental problems using simulation tools requires addressing end-user and stakeholder requirements during early stages of problem development. In doing so, we avoid modelling and simulation as an end of its own.  相似文献   
22.
This paper presents the cost optimization of an urban drainage and wastewater treatment system. The mixed sewer urban drainage (including combined sewer overflows and retention basins), the activated sludge wastewater treatment plant (WWTP), and the permissible loading of the receiving water were optimized simultaneously by the nonlinear programming approach. For this purpose, the integrated optimization model OPTIMALWWT was developed. The economic objective function of the defined investment and operational costs is subjected to rigorous design and ecological constraints. A practical example of the cost optimization of an existing urban drainage and WWTP, located in Slovenia, is presented to demonstrate the efficiency of the proposed method. For each of the two different design approaches, three different optimization cases were carried out for three different technological alternatives. As a result, the optimal technological process was finally selected for the reconstruction of the system, as a result of its suitable costs and operational safety.  相似文献   
23.
Objective: This study examined the risk factors of driving under the influence of alcohol (DUI) among drivers of specific vehicle categories (DSC). On the basis of this research, the variables related to DUI and involvement in traffic crashes were defined. The analysis was conducted for car drivers, bicyclists, motorcyclists, bus drivers, and truck drivers.

Method: The research sample included drivers involved in traffic crashes on the territory of Serbia in 2016 (60,666). Two types of analyses were conducted in this study. Logistic regression established the correlation between DUI and DSC and the The Technique for Order of Preference by Similarity to Ideal Solution (Multi-criteria decision making) method was applied to consider the scoring and explore the potential for the prevalence of DUI on the basis of 2 data sets (DUI and non DUI).

Results: The study results showed that driver error and male drivers were the 2 most significant risk factors for DUI, with the highest scores and potential for prevalence. The nonuse of restraint systems, driver experience, and driver age are the factors with a significant prediction of involvement in an accident and an insignificant prediction of DUI.

Conclusions: Following the development of the logistic prediction models for DUI drivers, testing of the model was conducted for 3 control driver groups: Car, motorcycle, and bicycle. The prediction model with a probability greater than 50% showed that 77% of car drivers were under the influence of alcohol. Similarly, the prediction percentage for motorcyclists and bicyclists amounted to 71 and 67%, respectively. The recommendation of the study is that drivers whose DUI probability is above 50% should be potentially suspected of DUI. The results of this study can help to understand the problem of DUI among specific driver categories and detect DUI drivers, with the aim of creating successful traffic safety policy.  相似文献   

24.
This study describes a novel wastewater treatment technology suitable for small remote northern communities. The technology is based on an enhanced biodegradation of organic carbon through a combination of anaerobic methanogenic and microbial electrochemical (bioelectrochemical) degradation processes leading to biomethane production. The microbial electrochemical degradation is achieved in a membraneless flow-through bioanode–biocathode setup operating at an applied voltage below the water electrolysis threshold. Laboratory wastewater treatment tests conducted through a broad range of mesophilic and psychrophilic temperatures (5–23 °C) using synthetic wastewater showed a biochemical oxygen demand (BOD5) removal efficiency of 90–97% and an effluent BOD5 concentration as low as 7 mg L?1. An electricity consumption of 0.6 kWh kg?1 of chemical oxygen demand (COD) removed was observed. Low energy consumption coupled with enhanced methane production led to a net positive energy balance in the bioelectrochemical treatment system.  相似文献   
25.
26.
The systems approach permits us to analyze national security as a cluster of interconnected elements, in which the environmental dimension appears to be the most important one. The environmental problem is divided into two main aspects: environmental security per se and the impact of environment on the overall status of a nation's security. It is argued here that the quality of life and health serve as both the main objective and the principal criterion of environmental security in a social system. Indices of these two factors are used in this article as indicators of the state of this type of security. They confirm that vast areas of Russia, the Ukraine, and Central Asia (especially the Aral Sea region) should be considered as presenting a substantial risk to local people and even producing global impacts on both natural and man-made systems. Environmental factors that destabilize national security are also divided into two groups: those that impact social systems directly and negatively (mainly natural disasters) and technological and sociopolitical agents that cause indirect impacts, in both war and peace time, as well as in the civil and military sectors of the economy. Developments in the former Soviet Union (the Commonwealth of Independent States) are used as an illustration of the consequences that such impacts may have on the status of national security.  相似文献   
27.
Transcervical cell (TCC) samples have been shown to contain fetal cells amenable to molecular analysis. However, the presence of ‘contaminating’ maternal cells limits their use for prenatal diagnoses. In this report we show that clumps of fetal cells can be isolated from transcervical samples by micromanipulation and tested by fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR). Out of 129 clumps, isolated from mucus aspirates and transcervical lavages from 29 patients, 29 clumps from 11 patients were found to be exclusively of fetal origin as judged by the detection of chromosome 21-specific polymorphic DNA markers and Y-derived DNA sequences by PCR and FISH. One case of a male triploid fetus, diagnosed by the analysis of TCC samples obtained by mucus aspiration and lavage, was confirmed by testing clumps of cells isolated by micromanipulation.  相似文献   
28.
An i(Yp) is a rare marker chromosome. We present a case of de novo 46,X,i(Yp) detected prenatally in an amniotic fluid specimen. Fluorescence in situ hybridization (FISH) studies using a panel of Y-specific biotinylated DNA probes identified the marker chromosome as i(Yp). Comparative genomic hybridization (CGH) studies further confirmed the diagnosis. Upon pregnancy termination, external examination of the fetus revealed a generally well-developed male fetus with slight facial dysmorphism and prominent rocker-bottom feet. The molecular cytogenetic data in this case proved very useful in genetic counselling and served as a good example illustrating the important role of molecular techniques for accurate identification of marker chromosomes.  相似文献   
29.
Objective: Red light cameras (RLCs) have generated heated discussions over issues of safety effectiveness, revenue generation, and procedural due process. This study focuses on the safety evaluation of RLCs in Missouri, including the economic valuation of safety benefits. The publication of the national Highway Safety Manual (HSM; American Association of State Highway and Transportation Officials) in 2010 produced statistical safety models for intersections and spurred the calibration of these models to local conditions.

Methods: This study adds to existing knowledge by applying the latest statistical methodology presented in the HSM and more current data. Driver behavior constantly changes due in part to driving conditions and the use of technology. The safety and economic benefit evaluation was performed using the empirical Bayes method, which accounts for regression to the mean bias. For the economic benefit evaluation, the KABCO crash severity scale and crash cost estimates were used. A total of 24 4-leg urban intersections were randomly selected from a master list of RLCs in Missouri from 2006 to 2011. Additionally, 35 comparable nontreated intersections were selected for the analysis.

Results and Conclusions: The implementation of RLCs reduced overall angle crashes by 11.6%, whereas rear-end crashes increased by 16.5%. The net economic crash cost benefit of the implementation of RLCs was $35,269 per site per year in 2001 dollars (approximately $47,000 in 2015 dollars). Thus, RLCs produced a sizable net positive safety benefit that is consistent with previous statistical studies.  相似文献   

30.
Foreign direct investment is an engine of economic growth. However, it may affect environmental quality (improve or deteriorate it), depending on the context. Under a multivariate framework, this paper aims to investigate the relationship between foreign direct investment and deforestation for Sub‐Sahara African countries with economic growth, trade openness and urbanization as additional determinants of deforestation. The analyses reveal that all variables are non‐stationary and cointegrated based on recent panel data techniques. On applying dynamic ordinary least squares, the long‐run results suggest the validity of the pollution haven hypothesis for some countries, and that of the pollution halo hypothesis for other countries. The findings are also mixed across Sub‐Sahara African countries for trade openness and urbanization. The results from this study suggest that Sub‐Sahara African countries should continue attracting foreign direct investment, while a certain number of them should put more emphasis on controlling deforestation associated with foreign direct investment inflows to limit greenhouse gas concentrations in the atmosphere.  相似文献   
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