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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.
181

The development of the emerging technologies sustainability assessment (ETSA) and its application in the design of a bioprocess for the treatment of wine distillery effluent

Khan, Nuraan January 2005 (has links)
Emerging Technologies Sustainability Assessment (ETSA) is a new technology assessment tool that was developed in order to compare emerging processes or technologies to existing alternatives. It utilizes infoIDlation modules, with the minimum use of resources such as time and money, in order to deteIDline if the process under development is comparatively favourable and should be developed beyond the early conceptual phase. The preliminary ETSA is vital in order to identify the gaps in the existing information and the specific methodologies to be used for data capture and analysis. The use of experimental design tools, such as Design-Expert, can facilitate rapid and efficient collection of necessary data and fits in well with the rationale for the ETSA. Wine distillery effluent (vinasse) is the residue left after alcohol has been distilled from fennented grape juice. It is an acidic, darkly coloured effluent, with a high COD and polyphenol content. The most popular method of disposal of this effluent, land application, is no longer viable due to stricter legislation and pressure on the industry to better manage its wastes. Although the ability of whiterot fungi to degrade a number of pollutants is well-known, fungal treatment of wine distillery effluent is still in the conceptual phase. The perfoIDlance of the fungal remediation system was assessed experimentally in terms of COD removal and laccase production using Design-Expert. Although Pycnoporus sanguine us was found to be most efficient at COD removal (85%) from 30% vinasse, laccase production was low (0.021 U/I). The optimum design for economically viable fungal treatment used Trametespubescens. This fungus was able to remove over 50% of the COD from undiluted vinasse while producing almost 800U/l of the valuable laccase enzyme within three days. Since the effluent from the fungal system did not meet the legal limits for wastewater disposal, a two-stage aerobicanaerobic system is suggested to improve the quality of the effluent prior to disposal. The ETSA was used to assess the fungal technology in relation to the two current methods of vinasse treatment and disposal, namely land application and anaerobic digestion. Based on the ETSA, which considered environmental, social and economic impacts, the fungal system proved to be potentially competitive and further development of the technology is suggested.
182

Effects of poor solid waste management on sustainable development in informal settlement

Mgwebi, Alicia Zoliswa January 2013 (has links)
The aim of this study is to investigate the effects of poor solid waste disposal on a sustainable environment/development in the Mzamomhle urban informal settlement. According to Coffey & Coad, (2010) informal or squatter urban communities pay no municipal taxes, because of their informal status, and this fact has often been used as the principal argument against providing these communities with municipal services.
183

Disposal of unused medicines from households in Cape Town

Okonkwo Ihebe, Miriam Oluchi January 2019 (has links)
Magister Pharmaceuticae - MPharm / Evidence indicates that most South African households do not dispose of unused medicines in the manner prescribed by the medicine’s regulatory authority. This trend is not unique to South Africa, but several developing nations have also lagged. An in-depth understanding of practices of disposal of unused as well as expired medicines is cardinal and critical to the development of an effective programme to reverse the situation. This study aimed to identify factors influencing the disposal practices of household unused and expired medicines, and the role of pharmacists in creating an efficient and robust system for proper disposal of unused medicine from households in the southern suburbs area of Cape Town.
184

System optimization in wastewater treatment plant design : network models for BOD and sludge treatment

Efstathiadis, Elias January 1977 (has links)
No description available.
185

On-Site Excreta Treatment and Disposal in West Africa

Igbokwe, Godfrey E. 01 July 1982 (has links) (PDF)
In operation, liquid from the test facility is circulated through the RHS core. The liquid is heated by passing over the resistance heaters. If the test facility's calibrations are under investigation, the RHS input power and temperatures are compared with those recorded by the test facility. If a collector is under test, the RHS is placed in series with the collector. The power input to the RHS is placed in series with the collector. The power input to the RHS core heaters is adjusted to give a temperature rise through the RHS equal to some fraction (usually one-half to one) of the temperature rise across the collector. Since the same mass flow passes through both the RHS and the collector, the energy gain in the collector is simply the RHS input power multiplied by the ratio of the temperature rises.
186

Exchangeable end effectors for the army Explosive Ordnance Disposal (EOD) robot

Chubb, Deborah M. 16 December 2009 (has links)
Explosive Ordnance Disposal (EOD) is assigned the mission to render safe and/or dispose of any device, conventional, nuclear, biological, chemical, or improvised, that may cause injury to personnel or damage to property. Teleoperated mobile robots have been fielded to make the job of the EOD soldier less hazardous. The current model in use is the Security Explosive Ordnance Disposal (SEOD) robot. The future model is the RCT Rover. These robots are designed to specifically target improvised explosive devices (IEDs) -- homemade bombs. With their present design these robots have limited capabilities. Only one gripper, which is bolted onto the end of the arm, is provided. It was the objective of the research to take the first step toward increasing the flexibility of this robot by applying technology which presently exists in the industrial robotics area. A feasibility study was proposed which considered both hardware and control issues of proposed changes. A quick exchange device was proposed as well as numerous end effectors to make the robot more adaptable to any given situation. Control and feedback system issues was also investigated that allowed the telerobot to have autonomous control during the end effector interchange sequence. / Master of Science
187

An assessment of medical waste management practices in the North-eastern Free State, South Africa / Pululu Sexton Mahasa

Mahasa, Pululu Sexton January 2013 (has links)
The proper handling and disposal of medical waste in accordance with national guidelines is very important. This study was undertaken to investigate the state of medical waste and management practices in different hospitals in the north-eastern Free State Province, South Africa. A random sample of ten (10) hospitals was selected. Observation of operations was carried over a period of six months. A stratified random sample of 138 staff members spread across the ten medical facilities was selected and face-to-face interviews were conducted. The hospitals were grouped into 3 categories namely large, medium and small in terms of the number of hospital beds. Data collection through observation and covered waste generation, storage, handling, transportation, treatment and management procedures. Data analysis made use of SPSS to generate descriptive statistics, correlation coefficients and t-tests in hypothesis testing. The findings reveal that medical personnel do not treat medical waste as specified in official guidelines, there is no formal training for personnel, medical waste is not a key priority, there are low levels of environmental awareness, inappropriate treatment of waste at some sites, and inadequate budget allocations for medical waste management. These findings indicate that there is an urgent need for addressing issues of awareness for managers, better on-the job training for personnel, better systems for on-ward conveyance of waste from facilities to official medical waste treatment plants, an up-grade of existing incinerators and a consistent schedule of data capture should be implemented. / Thesis (Msc Env Science) North-West University, Mafikeng Campus, 2013
188

A graph-theory-based C-space path planner for mobile robotic manipulators in close-proximity environments

Wall, D G 10 August 2016 (has links)
In this thesis a novel guidance method for a 3-degree-of-freedom robotic manipulator arm in 3 dimensions for Improvised Explosive Device (IED) disposal has been developed. The work carried out in this thesis combines existing methods to develop a technique that delivers advantages taken from several other guidance techniques. These features are necessary for the IED disposal application. The work carried out in this thesis includes kinematic and dynamic modelling of robotic manipulators, T-space to C-space conversion, and path generation using Graph Theory to produce a guidance technique which can plan a safe path through a complex unknown environment. The method improves upon advantages given by other techniques in that it produces a suitable path in 3-dimensions in close-proximity environments in real time with no a priori knowledge of the environment, a necessary precursor to the application of this technique to IED disposal missions. To solve the problem of path planning, the thesis derives the kinematics and dynamics of a robotic arm in order to convert the Euclidean coordinates of measured environment data into C-space. Each dimension in C-space is one control input of the arm. The Euclidean start and end locations of the manipulator end effector are translated into C-space. A three-dimensional path is generated between them using Dijkstra’s Algorithm. The technique allows for a single path to be generated to guide the entire arm through the environment, rather than multiple paths to guide each component through the environment. The robotic arm parameters are modelled as a quasi-linear parameter varying system. As such it requires gain scheduling control, thus allowing compensation of the non-linearities in the system. A Genetic Algorithm is applied to tune a set of PID controllers for the dynamic model of the manipulator arm so that the generated path can then be followed using a conventional path-following algorithm. The technique proposed in this thesis is validated using numerical simulations in order to determine its advantages and limitations.
189

Retention and Disposal of Engineering data

Smith, Matthew Bede January 2014 (has links)
This project aims to identify data usage, look into the establishment of data management techniques and provide guidance for staff as to efficient storage measures. The project provides recommendations for a robust policy framework to offer engineering departments guidance on the principles behind information management. There is to be the identification of potential categorises and associated retention times. Categorisation will assist in giving data a retention time and increase the efficiency of accessing data. The main drivers for this project include $5million spent over three years on the storage of electronic information and the difficulties associated with finding information in high volume storage systems. These issues are increasing exponentially as Beca grows and as the size and quantity of CAD, photos and videos files increases.
190

Centrifuge modelling of the dynamic embedment of a heat emitting projectile in normally consolidated clay

Poorooshasb, Farrokh January 1987 (has links)
No description available.

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