Evaluation of contaminated sites based on human health and environmental hazards is an essential task for the proper management of the contaminated sites. A large number of contaminated sites have been waiting for remediation all over the World. However, contaminated site remediation is generally a difficult, time consuming and very expensive process. Ranking systems for contaminated sites are useful tools to determine the remedial priority and to manage the available remediation budget in the most efficient way before the costly remedial actions are taken. To be able to have a reliable ranking result, accurate and sufficient amount of data on the nature of contamination and site characteristics are needed, which are usually not available at the early identification phases of contaminated sites, and the available data is mostly limited and vague in nature. If the available data are inaccurate or vague, the corresponding remedial ranking results can be questionable, as well. Most of the current ranking methodologies overlook the vagueness in the parameter values. The main objective of this study is to develop a remedial priority ranking system for contaminated sites by taking vagueness in parameter values into account. Within this context, development of the new Remedial Priority Ranking System, RPRS, aims to define and evaluate the current and possible environmental risks by using sufficiently comprehensive readily available parameters describing the fate and transport of contaminants in the environment and considering vagueness in those parameter values. The consideration of vagueness in parameter values was included in remedial prioritization of contaminated sites by means of fuzzy set theory. A fuzzy expert system was built up for the evaluation of contaminated sites and it was developed in Microsoft Office Excel 2007 platform, with the intention of making the evaluation fast and user friendly. Hypothetical and real case study applications are presented to test ease of use and validity of the results of the developed methodology. Results of case study applications revealed that the developed RPRS can serve as an alternative method for remedial priority ranking of contaminated sites.

Water quality issues in the Leon River watershed in Texas exemplify the challenges water resource managers and the public face in the ongoing effort to improve water quality in our nation’s water bodies. Some pollutant sources are difficult to regulate and likely managed through non-regulatory means, such as voluntary action. The Leon River challenge is how to go beyond regulations to address the concerns of citizens and produce options they want to develop and implement voluntarily that address a common good. This dissertation argues that voluntary measures work only if those who must take action support the action, otherwise conflict can occur. Thus, it is critical to learn what people are willing to do to promote the public good (e.g., swimmable streams). This can be achieved through an effective public process. Public participation processes may have barriers that impede success, such as inadequate access, intimidation, competing interests, limited accountability, and scientific mistrust. This dissertation developed process enhancements to overcome these barriers based on documented public participation principles. This research tested whether specific enhancements can improve the quality of a public process and achieve desired process outcomes. This dissertation reports on quasi-experiments with stakeholders making actual environmental decisions. The findings suggest that these enhancements are capable of reducing conflict and reducing the time to produce environmental policy. Five process enhancements (representation, film, narratives, deliberative decision-making, and decision support) were put into operation to provide options for government agencies and stakeholders to consider when undertaking public participation processes. The lack of access can be avoided by giving stakeholders voice with representation through different types of meetings levels (e.g., focus groups and town hall meetings). Films, when captured, edited, and shown to others, can remove the mechanisms typically associated with the intimidation perceived by speakers during discussions. Narratives were used to collect information about stakeholders to develop a deeper understanding of the diversity of interests affected by a policy, avoiding gridlock from positional bargaining. Deliberative decision-making (no voting) can assure stakeholders have real and equitable decision-making power, with scenarios collaboratively developed that address the common good. Application of a decision support system (DSS) as an overlay to a scientific model can provide stakeholders direct access to science so they can develop scenarios, evaluate alternatives, and choose solutions. / text

Chapter 2 considers technology adoption under both technological and subsidy uncertainties. Uncertainty in subsidies for green technologies is considered as an example. Technological progress is exogenous and modeled as a jump process with a drift. The analytical solution is presented for cases when there is no subsidy uncertainty and when the subsidy changes once. The case when the subsidy follows a time invariant Markov process is analyzed numerically. The results show that improving the innovation process raises the investment thresholds. When technological jumps are small or rare, this improvement reduces the expected time before technology adoption. However, when technological jumps are large or abundant, this improvement may raise this expected time. Chapter 3 studies technology adoption in a duopoly where the unbiased technological change improves production efficiency. Technological progress is exogenous and modeled as a jump process with a drift. There is always a Markov perfect equilibrium in which the firm with more efficient technology never preempts its rival. Also, a class of equilibria may exist that lead to a smaller industry surplus. In these equilibria either of the firms may preempt its rival in a set of technology efficiency values. The first investment does not necessarily happen at the boundary of this set due to the discrete nature of the technology progress. The set shrinks and eventually disappears when the difference between firms’ efficiencies increases. Chapter 4 studies the behavior of two firms after a new investment opportunity arises. Firms either invest immediately or wait until market uncertainty is resolved. Two types of separating equilibrium are possible when sunk costs are private information. In the first type the firm with lower cost invests first. In the second type the firm with higher cost invests first leading to a smaller industry surplus. The results indicate that the second type is possible only for strictly negatively correlated sunk costs. Numerical analysis illustrates that when first mover advantage is large, the firm that delays the investment should be almost certain about its rival’s sunk cost. When market risk increases, the equilibria can exist when the firm is less certain. / text

Šiame darbe tiriama švarių paviršių paruošimo sūkuriniu pulsuojančiu srautu galimybė. Darbo tikslas: išsiaiškinti švarių paviršių paruošimo galimybę, naudojant vandens srautą, kuriame turbulencijos lėtėjimo dėka sukeliama kavitacija. Darbas sudarytas iš keturių dalių. Pradžioje apibūdinami švarūs paviršiai, jų klasifikacija. Toliau apžvelgiami švarių paviršių paruošimo metodai, problemos. Po to, skaitmeninės simuliacijos būdu, tiriamos sūkurinį pulsuojantį srautą generuojančių purkštukų konstrukcijos. Eksperimentinėje dalyje pateikiami bandymo rezultatai, kuomet iš aliumininės plokštelės šalinamos abrazyvo liekanos, įstrigusios paviršiuje šlifavimo metu. Darbo pabaigoje pateikiamos išvados. Darbo apimtis – 51 psl. teksto be priedų, 36 iliustracijos, 3 lentelės, 13 bibliografinių šaltinių. Atskirai pridedami darbo priedai. / This study investigates the preparation of clean surfaces with pulsating vortex flow option. The aim of work: to determine the possibility of clean surface preparation using a water flow with generated cavitation. The work consists of four parts. At the start of the work characterized clean surfaces and their classification. The following provides an overview of clean surface preparation methods, problems. After that, the digital simulation method investigated vortex-generating jets pulsating flow structures. In the experimental part are presented the test results, when the aluminum plate is disposed abrasive residues trapped on the surface of the grinding time. At the end of the work there are given conclusions. Work size - 51 text pages without appendixes, 36 figures, 3 tables, 13 bibliographical sources.

Concern on a global scale gave rise to the founding of the Stockholm Convention on persistent organic pollutants (POPs) with a view to restrict the use and production of these toxic chemicals. As a signatory, South Africa is legally bound to abide to the Convention’s objectives, including participating in relevant research and monitoring. However, developing countries such as South Africa have limited information concerning POPs, partially because these countries do not have sufficient analytical capabilities, and thus method development and refinement are necessary. One group of POPs consisting of polychlorinated dibenzo-pdioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs), collectively referred to as dioxins, are of particular concern due to their high toxicity and persistence. Additionally, the analysis of dioxins is recognised as one of the most analytically challenging of its kind. This study investigated the effect of different preparatory protocols on the semi-quantification of dioxins using the H4IIE-luc-reporter gene assay. The protocols evaluated were either Soxhlet or pressurised liquid extraction (PLE) combined with a manual acid digestion, gel permeation chromatography (GPC) and Florisil fractionation clean-up procedure as well as the automated Total Rapid Prep™(TRP) system which makes use of a PLE combined with a multi-layer silica, alumina and carbon column clean-up procedure. To evaluate the protocols, an eight point matrix matched calibration curve, two soil samples and a certified reference material (CRM) were used. The extracts were semi-quantified by the H4IIE-luc bio-assay. During the course of the assay, the appropriateness of different standards was investigated, and a mixed standard containing all 17 toxic PCDD/Fs was chosen for quantification. During the data review process, higher bioassay equivalent (BEQ) values were obtained from PLE compared to Soxhlet extraction, while no statistically significant difference (Kruskal-Wallis ANOVA: p > 0.05) was found between the assay quantifications for the different preparatory techniques. However, the results of the H4IIE bio-assay were larger than the expected values. The identity of the chemicals that were in all likelihood responsible for the higher response was investigated through instrumental analysis using comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry (GCxGC-TOFMS). Instrumental results indicated a high level of PAHs in the extracts, which could lead to super induction of the aryl hydrocarbon receptor (AhR) and therefore, to a positive bias in the results. Instrumental screening proved that all selected preparatory protocols were inadequate at removing interfering compounds and not sufficiently selective for PCDD/Fs, although the TRP was more successful in removing interferences. The high matrix interference hindered peak identification. Additionally, as indicated by instrumental analysis, the weak recovery of PCDD/Fs could be ascribed to high evaporation temperatures. The effect of different reference standards in the H4IIE bio-assay used during semi-quantification needs further investigation; similarly, the optimisation of extraction, evaporation and clean-up protocols and the use of different GCxGC-TOFMS column combinations aimed at more efficient separation needs to be investigated. The assistance of the National Metrology Institute (funded through the Department of Trade and Industry) towards this research is hereby acknowledged. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

Concern on a global scale gave rise to the founding of the Stockholm Convention on persistent organic pollutants (POPs) with a view to restrict the use and production of these toxic chemicals. As a signatory, South Africa is legally bound to abide to the Convention’s objectives, including participating in relevant research and monitoring. However, developing countries such as South Africa have limited information concerning POPs, partially because these countries do not have sufficient analytical capabilities, and thus method development and refinement are necessary. One group of POPs consisting of polychlorinated dibenzo-pdioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs), collectively referred to as dioxins, are of particular concern due to their high toxicity and persistence. Additionally, the analysis of dioxins is recognised as one of the most analytically challenging of its kind. This study investigated the effect of different preparatory protocols on the semi-quantification of dioxins using the H4IIE-luc-reporter gene assay. The protocols evaluated were either Soxhlet or pressurised liquid extraction (PLE) combined with a manual acid digestion, gel permeation chromatography (GPC) and Florisil fractionation clean-up procedure as well as the automated Total Rapid Prep™(TRP) system which makes use of a PLE combined with a multi-layer silica, alumina and carbon column clean-up procedure. To evaluate the protocols, an eight point matrix matched calibration curve, two soil samples and a certified reference material (CRM) were used. The extracts were semi-quantified by the H4IIE-luc bio-assay. During the course of the assay, the appropriateness of different standards was investigated, and a mixed standard containing all 17 toxic PCDD/Fs was chosen for quantification. During the data review process, higher bioassay equivalent (BEQ) values were obtained from PLE compared to Soxhlet extraction, while no statistically significant difference (Kruskal-Wallis ANOVA: p > 0.05) was found between the assay quantifications for the different preparatory techniques. However, the results of the H4IIE bio-assay were larger than the expected values. The identity of the chemicals that were in all likelihood responsible for the higher response was investigated through instrumental analysis using comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry (GCxGC-TOFMS). Instrumental results indicated a high level of PAHs in the extracts, which could lead to super induction of the aryl hydrocarbon receptor (AhR) and therefore, to a positive bias in the results. Instrumental screening proved that all selected preparatory protocols were inadequate at removing interfering compounds and not sufficiently selective for PCDD/Fs, although the TRP was more successful in removing interferences. The high matrix interference hindered peak identification. Additionally, as indicated by instrumental analysis, the weak recovery of PCDD/Fs could be ascribed to high evaporation temperatures. The effect of different reference standards in the H4IIE bio-assay used during semi-quantification needs further investigation; similarly, the optimisation of extraction, evaporation and clean-up protocols and the use of different GCxGC-TOFMS column combinations aimed at more efficient separation needs to be investigated. The assistance of the National Metrology Institute (funded through the Department of Trade and Industry) towards this research is hereby acknowledged. / Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2013.

Bakgrund: I Sverige lever cirka 5000 personer med spinalskada. Där spinalskadan lett till nedsatt blåsfunktion är ren intermittent kateterisering (RIK) den metod som rekommenderas i första hand. Syfte: Att undersöka hur personer med traumatisk spinalskada som använder ren intermittent kateterisering (RIK) upplever detta. Syftet var även att ta reda på vilka hanteringsstrategier som finns för att underlätta det dagliga livet. Metod: En kvalitativ metod med semistrukturerade intervjuer användes där fem personer med traumatisk spinalskada som använder RIK intervjuades. Resultat: Att behöva tillägna sig metoden väckte blandade känslor. Män upplevde det lättare att RIKa jämfört med kvinnor. Den egna kompetensen och kunnandet om metoden RIK ökade med tiden och de hittade nya hanteringsstrategier för att underlätta vardagen. Informanterna var medvetna om vikten av god hygien för att undvika urinvägsinfektioner. Däremot framgick det inte om informanterna var medvetna om kopplingen mellan vikten av regelbunden RIKning, residualurin i blåsan och uppkomsten av urinvägsinfektioner. Slutsats: Personer som använder RIK upplever det som nödvändigt och avgörande för att kunna leva ett normalt liv. Hanteringsstrategier är planering och anpassande av metoden efter fysisk förmåga och den egna vardagen. Behovet av stöd hos personer med spinalskada som använder RIK är individuellt och varierar. Adekvat stöd och utbildning underlättar och hjälper personer med nedsatt blåsfunktion som använder RIK att ta kontroll över utövandet och främjar följsamheten och långsiktig hälsa avseende urinvägarna. / Background: About 5,000 people in Sweden live with a spinal injury. Where the spinal injury leads to impaired bladder function, clean intermittent catheterization (CIC) is the method recommended in the first place. Aim: To examine  how individuals  with traumatic  spinal injury  using clean  intermittent catheterization experience the method. The aim was also to find out coping strategies available to facilitate daily life. Methods: A qualitative approach with semi-structured interviews was used where five people with traumatic spinal injury were interviewed. Results: The need to use CIC brought about mixed feelings among informants. Men felt that it was easier for them to use clean intermittent catheterization compared to women. Their expertise and knowledge increased with time and they found new coping strategies to facilitate everyday life. The informants were aware of the importance of good hygiene to prevent urinary tract infections. However, it was not clear if the informants were aware of the connection between the importance of using clean intermittent catheterization regularly, residual urine in the bladder and the occurrence of  urinary  tract  infections. Conclusion: People who use CIC experience it as essential and vital in order to live a normal life. The need for support of people with spinal injury who use CIC is individual and varies. Adequate support and training for people with impaired bladder function using CIC facilitates and helps them to take control initially and promotes an ongoing adherence and long-term health regarding urinary tract.

The ‘hydrogen economy’ represents an energy system in which hydrogen and electricity are the dominant energy carriers for use in transportation applications. The ‘hydrogen economy’ minimizes the use of fossil fuels in order to lower the environmental impact of energy use associated with urban air pollution and climate change. An integrated energy system is required to deal with diverse and distributed energy generation technologies such a wind and solar which require energy storage to level energy availability and demand. A distributed ‘energy hub’ is considered a viable concept in envisioning the structure of an integrated energy system. An energy hub is a system which consists of energy input/output, conversion and storage technologies for multiple energy carriers, and would provide an interface between energy producers, consumers, and the transportation infrastructure. Considered in a decentralized network, these hubs would form the nodes of an integrated energy system or network. In this work, a model of a clean energy hub comprising of wind turbines, electrolyzers, hydrogen storage, a commercial building, and a fleet of plug-in fuel cell vehicles (PFCVs) was developed in MATLAB, with electricity and hydrogen used as the energy carriers. This model represents a hypothetical commercial facility which is powered by a renewable energy source and utilizes a zero-emissions fleet of light duty vehicles. The models developed herein capture the energy and cost interactions between the various energy components, and also calculate the CO2 emissions avoided through the implementation of hydrogen economy principles. Wherever possible, similar models were used to inform the development of the clean energy hub model. The purpose of the modelling was to investigate the interactions between a single energy hub and novel components such as a plug-in fuel cell vehicle fleet (PFCV). The final model reports four key results: price of hub electricity, price of hub hydrogen, total annual costs and CO2 emissions avoided. Three scenarios were analysed: minimizing price of hub electricity, minimizing total annual costs, and maximizing the CO2 emissions avoided. Since the clean energy hub could feasibly represent both a facility located within an urban area as well as a remote facility, two separate analyses were also conducted: an on-grid analysis (if the energy hub is close to transmission lines), and an off-grid analysis (representing the remote scenarios). The connection of the energy hub to the broader electricity grid was the most significant factor affecting the results collected. Grid electricity was found to be generally cheaper than electricity produced by wind turbines, and scenarios for minimizing costs heavily favoured the use grid electricity. However, wind turbines were found to avoid CO2 emissions over the use of grid electricity, and scenarios for maximizing emissions avoided heavily favoured wind turbine electricity. In one case, removing the grid connection resulted in the price of electricity from the energy hub increasing from $82/MWh to $300/MWh. The mean travel distance of the fleet was another important factor affecting the cost modelling of the energy hub. The hub’s performance was simulated over a range of mean travel distances (20km to 100km), and the results varied greatly within the range. This is because the mean travel distance directly affects the quantities of electricity and hydrogen consumed by the fleet, a large consumer of energy within the hub. Other factors, such as the output of the wind turbines, or the consumption of the commercial building, are largely fixed. A key sensitivity was discovered within this range; the results were ‘better’ (lower costs and higher emissions avoided) when the mean travel distance exceeded the electric travel range of the fleet. This effect was more noticeable in the on-grid analysis. This sensitivity is due to the underutilization of the hydrogen systems within the hub at lower mean travel distances. It was found that the greater the mean travel distance, the greater the utilization of the electrolyzers and storage tanks lowering the associated per km capital cost of these components. At lower mean travel distances the utilization of the electrolyzers ranged from 25% to 30%, whereas at higher mean travel distances it ranged from 97% to 99%. At higher utilization factors the price of hydrogen is reduced, since the cost recovery is spread over a larger quantity of hydrogen.

Biogas is a gaseous composition formed mainly by the methane gas (CH4) and by the carbon dioxide (CO2), generated especially by microbiologic processes in environment with few or no oxygen. This research was carried out on the biogas produced from the treatment of swine dejections in breathing decomposition and accumulated in the interior of biodigestors, in swine culture in the state of Rio Grande do Sul. Within the range of this present work, the same gas is rusted and it turns into CO2 by the burning in flare. Through the literature review and applied questionnaires, possibilities of treatment of swine objections were raised, through comparative flow chart. Through measuring the biogas flow in appropriate equipments and mathematic analyses, several conclusive results were reached. It was tried to evidence not only the various possibilities of biogas use, mainly the generation of electric energy, but also the heating of swine culture in the winter. It was approached the necessary equipments to invest in the first item mentioned, as well as deadlines for these investments return. From another point of view , it was evidenced the biogas nonuse in aid of the swine culture, but the investment in a Mechanism of Clean Development (MCD) to obtain the Credits of Carbon, where it was observed the great difficulties, mainly financial, to a swine breeder implant the same. Several technical and economical possibilities to mitigate the greenhouse effect were analyzed. / Biogás é uma composição gasosa formada principalmente pelo gás metano (CH4) e pelo dióxido de carbono (CO2), gerado especialmente por processos microbiológicos em ambiente com pouco ou nenhum oxigênio. Esta pesquisa foi realizada sobre o biogás produzido a partir do tratamento de dejetos suínos em decomposição anaeróbica e acumulado no interior de biodigestores, em suinocultura do Estado do Rio Grande do Sul. No âmbito do presente trabalho, o mesmo é oxidado e transforma-se em CO2 pela queima em flare. Através da revisão da literatura e questionários aplicados, foram levantadas possibilidades de tratamento dos dejetos suínos, através de fluxogramas comparativos. Através da medição da vazão do biogás em equipamentos apropriados e análise matemática, obteve-se resultados conclusivos. Procurou-se evidenciar as diversas possibilidades de aproveitamento do biogás, principalmente a geração de energia elétrica, mas também o aquecimento da suinocultura no inverno. Abordou-se os equipamentos necessários para investir no primeiro item anteriormente citado, assim como prazos para retorno destes investimentos. De outro ângulo de visão , evidenciou-se o não aproveitamento do biogás em benefício da suinocultura, mas o investimento em um Mecanismo de Desenvolvimento Limpo (MDL) para obter os Créditos de Carbono, onde observou-se as grandes dificuldades, principalmente financeiras, para um suinocultor implantar o mesmo. Diversas possibilidades técnicas e econômicas para mitigar o efeito estufa foram analisadas.

Water quality has been an issue of concern since the settlement of man and continues to be of great concern today in many locations around the world. In the United States, to address the issues of water pollution, the U.S. Congress passed the Clean Water Act (CWA) in 1972. This study examines the implementation and prioritization of impaired water bodies listed on the Illinois CWA section 303(d) list between 1992 and 2004. This study used the Delphi survey method to obtain opinions from water quality/management experts that reside in the state of Illinois. The goal of this study was to determine if a consensus could be reached amongst water quality experts on the severity of individual water pollutants for a given designated use of a water body by assigning weights, determining if any prioritization trends exist within the current Illinois 303(d) process, as well as identifying any shortcomings of the process and suggesting possible modes of improvement. The survey identified four major shortcomings of Illinois' current approach to water quality management: 1) limited funding and manpower, 2) lack of coordination/monitoring, 3) failure to regulate point sources, and 4) lack of biological monitoring. The survey respondents indicated that the entire state needs attention in terms of water quality improvement and that agriculture and urban runoff are the most important sources of water pollution and water body impairment. They rated the current prioritization system as being between "average" and "good" and identified that development of a weighting scheme could be feasible as long as it received adequate funding and adequate stakeholder support. The measure of consensus among respondents regarding weights for individual pollutants and designated uses varied significantly; however, the overwhelming majority of consensus values improved after participants were asked to revise their original responses in an effort to move towards central tendency in the distribution of assigned ranks.