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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
621

Uplatnění metodiky Lean Office ve fotbalovém průmyslu / Application of the Lean Office methodology in the Football Industry

Pylypchuk, Oleg January 2015 (has links)
Abstract This Master´s Thesis focuses on the analysis of the business processes within the football clubs, especially the Liverpool FC. The aim of the thesis is to analyze the processes within the football club and to propose the way how to improve them by using the Lean Office methodology There are prerequisits that a vast amount of the processes are not being performed well in the Football Industry. That is why this topic should be very actual for this industry. The basic theoretical aspects of the Lean Office had been described in the thesis, as well as the aproach how to map the process and exact tools had also been described. Then the business process of acquiring of a new player is analyzed and the possible solution how to improve it is proposed. Those ideas have to be drivers for the ongoing improvement for the industry by implementing the Lean philisophy throughout it.
622

A bench scale experimental study of the treatment of milking centre effluent using a sequencing batch reactor

Tam, James Ping-Cheong January 1985 (has links)
Until recently, the management of milking parlour effluent has received very little attention. The wastewater produced by milking operations comprises mainly milk solids and manure and can impose environmental threats to nearby water bodies if not properly treated before disposal. In this study, three bench-scale Sequencing Batch Biological Reactors were used to treat the UBC dairy barn milking centre wastewater. The experiment was designed to investigate the treatment efficiency of the reactors under different operating temperatures and different numbers of cycles employed per unit daily flow (for the same hydraulic retention time). Parameters studied included BOD₅, COD, Total Suspended Solids, NH₃-N, N0₂-NO₃-N and dissolved oxygen uptake. It was concluded that very high and consistent treatment efficiency can be achieved by using a Sequencing Batch Biological Reactor to treat milking centre wastes. Over 90% BOD₅ removal was observed in the room temperature and 30°C reactors. Even in low operating temperatures of 3.7 and 10.5°C, over 70% BOD₅ removal was attained. Removal of the other pollutional parameters studied was similarly excellent. Uncontrolled denitrification also occured to various degrees in all three reactors. It was also concluded that within the range studied in this experiment (4 to 8 cycles per day), changing the number of cycles employed per unit daily flow did not have any significant effect on the treatment efficiency of the reactors. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
623

The renovation of domestic effluent through a forest soil

Bryck, John Michael Guy January 1977 (has links)
An investigation of the trend over time of the concentration of selected soil leachate constituents contained in domestic effluent applied to a ferro-humic podzol forest soil was undertaken. From July 15, 1976 to November 12, 1976, 2 cm of domestic effluent, selectively supplemented with commercial fertilizer, was sprayed twice weekly to a 900 m² plot situated on a mountain slope. Ten porous plate tension lysimeters installed at various depths and locations in the forest soil continuously extracted the resulting soil leachate. The soil leachate samples collected twice per week over the duration of the study, as well as the applied effluent samples, were analysed for chloride, nitrate and total Kjeldahl nitrogen and total and orthophosphorus. Based on. the concentrations of nitrate nitrogen, total Kjeldahl nitrogen, and total phosphate in the applied effluent as well as the average volume of effluent applied over the total irrigation plot, k8A kg/ha (^3.2 lb/acre) nitrate nitrogen, 93-7 kg/ha (83-6 lb/acre) total Kjeldahl nitrogen, and ^3.5 kg/ha (38.6 lb/acre) of total phosphate were applied to the plot during the project period. The chloride ion gradually increased in concentration over the duration of the study until it eventually equalled the value of the chloride in the domestic effluent. This gradual increase was a possible result of the retention of the initial amounts of applied chloride on the anion exchange sites in the soil, which when satisfied, allowed subsequent amounts of applied chloride to move through the soil with the applied effluent. No ortho or total phosphorus was detected in the soil leachate samples collected over the duration of the study. While recognizing the possibility of microbiological immobilization of a portion of the applied phosphorus, the most likely retention mechanism was the adsorption of the phosphorus by the amorphous iron and aluminum compounds in the soil. Nitrate and total Kjeldahl nitrogen were detected in low concentrations in the soil leachate samples only in the time interval following the application of domestic effluent containing greatly increased effluent concentrations of nitrate and total Kjeldahl nitrogen. The increased concentrations resulted from the addition of commercial fertilizers to the treatment lagoon. Such trends suggest microbiological immobilization was playing a role in the removal of the nitrogen compounds. The retention of ammonia, the major component of total Kjeldahl nitrogen, on the cation exchange sites and the retention of nitrate nitrogen on the anion exchange sites would also be occurring. In order to investigate the magnitude of the reaction between phosphorus and the iron and aluminum compounds in the podzol soil, batch scale laboratory tests were undertaken. The time-phosphorus adsorption results indicate that the phosphorus reacts very quickly with the amorphous iron and aluminum compounds in the soil on the plot. The Langmuir and Freundlich isotherms were calculated as was the phosphorus adsorption maximum based on the Langmuir isotherm. The calculated phosphorus adsorption would probably give a conservative estimate of the phosphorus removal potential since the isotherm is based only on the initial and not the long term phosphorus adsorption reactions. Despite the fact that the soil water content was continually above the soil water content at the field capacity, no phosphorus and very little nitrogen was detected in the soil leachate samples. Such results suggest that a phosphorus or nitrogen balance may be a useful irrigation operating criterion rather than the commonly accepted water balance criterion. In such a situation the phosphorus or nitrogen requirements over the growing season of the crop would be evaluated and met by the application of domestic effluent. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
624

Treatment of a municipal landfill leachate

Lee, Ching Jiang January 1979 (has links)
One of the problems associated with the disposal of solid wastes in landfills, particularly in high precipitation areas, is the pollution caused by the production of the often highly contaminated leachate. This study was initiated to investigate the treatability of a low-strength municipal landfill leachate using aerobic digestion followed by activated carbon polishing, so that the most cost effective treatment system could be determined. Sludge desorption and leachate toxicity assessment were also included in the study. The aerated lagoon process alone was very effective in treating the leachate to a quality that is nearly acceptable for discharge to a receiving water. Only SO₄ and Fe in the settled effluent significantly exceeded the local requlatory standards for specific discharges. Carbon adsorption greatly improved the settled effluent quality in terms of color, Fe and COD. However, the addition of this polishing process for combined treatment may not be cost effective. For an influent COD of 1,600 mg/1 and with MLVSS concentrations ranging between 360 and 560 mg/1, the settled effluent COD removal increased from 82.6% to as high as 90.1% when 9C was increased from 2 to 10 days. For the corresponding influent BOD5 of about 1,000 mg/1 and with θ[sub c] greater than 3 days, the BOD5 removal efficiencies averaged 99.1% and the settled effluent BOD5's were no greater than 10 mg/1. This indicates that the raw leachate can be almost completely biodegraded by aerobic digestion. The metal removal efficiency in aerobic treatment was greater than 95% for Fe and Mn, better than 90% for Zn and Pb, and about 80% for Al. Metals expected to be mainly or significantly removed by chemical precipitation due to pH change during treatment included Ca, Fe, Mn, Zn and Pb. Analysis of the kinetic parameters associated with the biological treatment indicated that the concentrations of pollutants, such as heavy metals, in the leachate were not great enough to cause significant inhibition of biological growth. It also showed that this leachate could very likely be added to a domestic sewage, in a high percentage, for aerobic treatment without producing adverse effects. From a treatment efficiency point of view, the optimum solids detention time was found to be 7 to 10 days for leachate BOD₅ ranging from 1,000 to 3,000 mg/1. However, since the predicted θ[sub c] for failure was 0.42 day at 22°C for a 1,000 mg/1 BOD₅ leachate, a θ[sub c] of 2 to 4 days seems possible in the field. On the other hand, the effects of winter temperature on BOD₅ removal and sludge settleability, as well as many other unknown factors on the overall biological treatment efficiency must be considered. It was, therefore, felt that a solids detention time of 5 days or more would be the more realistic approach for a full-scale treatment system, despite the fact that an economic analysis favored a shorter θ[sub c]. / Applied Science, Faculty of / Civil Engineering, Department of / Unknown
625

Detoxification of bleached kraft mill effluents by foam separation

Ng, Kong Seng January 1977 (has links)
Foam separation has been successfully developed on a 4-1 laboratory column, an 80-1 field column installation and a 6000 gal pilot plant trough type system as a novel process for detoxifying bleached kraft mill effluents. Toxic surface active materials such as resin and unsaturated fatty acids collect at the gas-liquid interface of rising air bubbles and concentrate in the foam. The highly toxic collapsed foam represents 1-2% by volume of the influent and is subsequently detoxified by biological treatment. Process parameters controlling detoxification efficiency are pH, gas-liquid interfacial area, initial toxicity level and mode of operation. The gas-liquid interfacial area and pH are of utmost importance. For a typical effluent with MST of 3-4 hr, approximately 20-2 30 m²/l of interfacial area given to an effluent at pH > 7.0 are required for detoxification. Foam separation is universally applicable and reliable for detoxifying kraft whole mill effluent. Over 80% of 205 samples from 10 Canadian mills were detoxified. A 1 gal/min, one and two stage continuous flow systems detoxified over 90% of samples at pH 8 and 1-2 hr retention time over 80 days of operation period. Study of detoxification mechanism indicated that foam fractionation accounts for 77.5% of detoxification, volatization for 5.4% and unidentified mechanisms for 17.1%. Depending on the mode of operation, up to 5% of effluent volume was discharged as foam. The foam volume could be reduced to < 2% by increasing foam retention time and enhancing internal reflux. Collapsed foam was readily detoxified by a biodisc or aerated lagoon process. In addition to detoxification, foam separation removed 20-60% of suspended solids, 66% resin acids, 12% B0D5 (10% TOC), 8% color and 80% foaming tendency. Suspended solids removal could be increased to 88% if an expensive dissolved air system were used for bubble generation. Commercially available equipment for foam generation and foam breaking was reviewed. Jet aerators and turbine systems were assessed as most suitable for commercial application. Pilot plant evaluation of this equipment indicated that reliable and consistent operation could be obtained. The results were used to establish empirical formulae for use in process scale up. During a 4 month continuous flow study, approximately 5-7 m²/l of gas-liquid interfacial area was provided to detoxify 80-100 gal/min of mill A effluent with MST of 6-10 hr. The detoxification success rate of a large number of samples increased from 50 to 86 and to 100% as the operation changed from 1 to 2 to 3 stages. The foam produced by the pilot plant was collapsed by a 12" diameter turbine at 100% efficiency all the time. Costs of foam separation were examined for a projected 3 stage foam separation process, treating 25 M gal/day of bleached kraft whole mill effluent. Capital costs for pH control, foam generation, foam breaking and foam treatment were estimated at $2.26 M. Operating costs were estimated at $2.35/ton of pulp. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
626

Protein generation and delignification of alder sawdust by thermophilic microorganisms

Wolde-Tsadick, Maheteme Selassie January 1978 (has links)
It has been indicated through a review of the literature that wood by-products have a potential as a dietary source of energy for the ruminant animal. However, lignin constitutes a barrier to the proper utilization of cellulose. Generally, any treatment to remove or alter lignin makes the cellulose within lignocellulose materials more susceptible to the activity of the cellulolytic enzymes. Therefore, an efficient biological treatment would require a system to solubilize or to remove lignin from the lignin-carbohydrate complex. Cellulose within ruminant feeds forms an effective substrate for eventual conversion to body protein. There are several methods available for delignification. This study was carried out using the thermophilic aerobic oxidation method for which swine manure was used both as the source inocula and initial culture media. In the process of degradation, a part of the energy produced was utilized by the bacteria for cell function and multiplication. The remainder of the available energy was released as heat energy. In this method the heat necessary to maintain the temperature in the thermophilic range was derived from both mechanical and from microbial activity. Thermophilic activity is considered to reduce the time required for organic waste digestion over that experienced by mesophilic digestion. The rate of the destruction of pathogenic bacteria, virus and other organisms is increased as a result of the high temperatures fermentation. Batch studies conducted to delignify alder sawdust by the use of the aerobic thermophilic oxidation method demonstrated that the lignin content of sawdust can be reduced by as much as 74%, and crude bacterial protein was generated by approximately 17%. Constant supply of small amounts of swine manure ensures high temperature maintenance. Periodical addition of 2 kg sawdust within thermophilic temperature range results in better delignification. / Land and Food Systems, Faculty of / Graduate
627

Analýza dopravních dat s vazbou na rizika v odpadovém hospodářství / Analysis of traffic data related to risks in waste management

Vaníček, Filip January 2020 (has links)
The aim of this thesis is to prepare real data for subsequent optimization of the collection plan using advanced VRP („Vehicle Routing Problem “) algorithms. The diploma thesis is motivated by the project Strategic Partnership for Environmental Technologies and Energy Production. The output focuses on indeterminate factors that have a major risk for subsequent operations. These are economic, environmental and social risks (overcrowded containers). Another result is the implementation and processing of the time-consuming passage of all streets, the estimation of the speed of the collection (garbage) truck for the subsequent optimization of the route and the estimation of the mean value of the filling of individual collection containers.
628

An assessment of solid waste management practices in rural areas : a case study of Shigalo

Simango, Thembi 10 January 2014 (has links)
B.URP / Department of Urban and Regional Planning
629

Annual Report 2015 Institute of Resource Ecology

Stumpf, Thorsten, Foerstendorf, Harald, Bok, Frank, Richter, Anke 28 July 2016 (has links)
The Institute of REsource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). The research activities are mainly integrated into the program “Nuclear Waste Management, Safety and Radiation Research (NUSAFE)” of the Helmholtz Association (HGF) and focused on the topics “Safety of Nuclear Waste Disposal” and “Safety Research for Nuclear Reactors”. Additionally, various activities have been started investigating chemical and environmental aspects of processing and recycling of strategic metals, namely rare earth elements. These activities are located in the HGF program “Energy Efficiency, Materials and Resources (EMR)”. Thus, all scientific work of the IRE belongs to the research field “Energy” of the HGF. The research objective is the protection of humans and the environment from hazards caused by pollutants resulting from technical processes that produce energy and raw materials. Treating technology and ecology as a unity is the major scientific challenge in assuring the safety of technical processes and gaining their public acceptance. We investigate the ecological risks ensued by radioactive and non-radioactive metals in the context of nuclear waste disposal, the production of energy in nuclear power plants and in processes along the value chain of metalliferous raw materials. A common goal is to generate better understanding about the dominating processes essential for metal mobilization and immobilization on the molecular level by using advanced spectroscopic methods. This in turn enables us to assess the macroscopic phenomena, including models, codes and data for predictive calculations, which determine the transport and distribution of contaminants in the environment.
630

An Assessment of Sustainable Solid Waste Management in Accra-Ghana

Deku, Pearl Sika 01 May 2020 (has links)
Despite the vast research on options to improve solid waste management (SWM) in developing countries, little has been done to evaluate these possible improvements. This study assesses Ghana’s Community Participation and Public Awareness Program (CPPAP) for SWM through qualitative interviews comprising of 81 community members living in three different Communities -Kanda, Asylum Down, and Nima all in the Accra Metropolitan Area (AMA), Ghana. In addition, four officials were interviewed, and an activity worksheet for Strength, Weakness, Opportunity, & Threat (SWOT) analysis was developed based on responses from the study community members and officials. Participants were asked to identify implementation plans for SWM at different levels of government. Results indicated that community members and officials do not have expert knowledge of existing local and national laws for managing waste in Ghana. Study participants were also asked what targets are achieved with CPPAP; the study observed that community members have a good comprehension of SWM and are actively involved in managing waste. Notwithstanding that, enforcement of the listed guidelines to CPPAP has not been effective primarily due to lack of resources. Furthermore, to identify community members’ and policymakers’ viewpoints regarding SWM, the study found that the greater support of the local government and all stakeholders is needed in managing waste. The study identified significant threats and weaknesses of the CPPAP that include political interference and a lack of resources that can be overcome by strengths and opportunities, including community mobilization, employment opportunities. The study contributes to the body of knowledge on assessing implementation programs and policies for solid waste management in developing countries. Stakeholders of solid waste management will also benefit from the challenges unveiled in the study regarding waste management implementation plans and policies from governments.

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