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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.
1

Marijampolės miesto centrinės dalies susisiekimo sistemos plėtra / Development of the communication system of the central part of the town of Marijampolė

Zokaitis, Egidijus 02 July 2009 (has links)
Darbo tikslas – įvertinti Marijampolės miesto centrinės dalies motorizuotos transporto infrastruktūros plėtros galimybes panaudojant transporto srautų modeliavimo programinę įrangą. Siekiant šio tikslo buvo apžvelgta pasaulio miestų susisiekimo sistemos plėtros tendencijos ir problematika, apžvelgtos transporto politikos susisiekimo kokybei gerinti, pasaulyje naudojama eismo modeliavimo įranga, išanalizuota Marijampolės miesto susisiekimo sistema. Pagal augantį miesto automobilizacijos lygį buvo prognozuotas automobilizacijos lygis 2017 metams. Buvo pasiūlyti 8 centrinės mieto dalies plėtros variantai. Šių variantų modeliavimo rezultatai buvo palyginti tarpusavyje, buvo pasirinkti 2 geriausi variantai ir atliktas jų ekonominis vertinimas. / The aim of the work: with the help of traffic modeling program to evaluate the Marijampolė city central part development scenarios. For such aim were analyzed world city’s transport system development trends and problems, transport policies to improve level of service, transport modeling programs and Marijampolė city transport system. Forecast of traffic flows prepared till 2017. During analysis 8 solutions were prepared how to improve level of service in the central part of the Marijampolė. According to traffic flows analysis with the “VISUM” program was made: basic model and 8 more models-solutions. Modeling results were compared and two best solutions were chosen to prepare economic estimations.
2

Análise da relação custo-benefício de projeto de eficiência energética no setor residencial

Lima, Luciana Oliveira da Silva 21 February 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-10-13T15:27:15Z No. of bitstreams: 1 DISS_2014_Luciana Oliveira da Silva Lima.pdf: 5079399 bytes, checksum: 88f713ee31918d76cd02f42ec13a598c (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-11-07T10:32:24Z (GMT) No. of bitstreams: 1 DISS_2014_Luciana Oliveira da Silva Lima.pdf: 5079399 bytes, checksum: 88f713ee31918d76cd02f42ec13a598c (MD5) / Made available in DSpace on 2017-11-07T10:32:24Z (GMT). No. of bitstreams: 1 DISS_2014_Luciana Oliveira da Silva Lima.pdf: 5079399 bytes, checksum: 88f713ee31918d76cd02f42ec13a598c (MD5) Previous issue date: 2014-02-21 / CAPES / Em projetos de eficiência elétrica, que envolve a troca de equipamentos convencionais por eficientes, existe a dificuldade de se estimar o consumo de energia elétrica ativa e a demanda de potência ativa, antes e após a execução do projeto. Porém, o software EnergyPlus tem se mostrado uma ferramenta eficaz para simulações termo energéticas, permitindo retratar os sistemas avaliados com operação muito próxima ao sistema real. Diante do expressivo aumento e a consequente necessidade do controle do consumo de energia elétrica pelo setor residencial, este trabalho propões analisar a viabilidade técnica e econômica do projeto de eficiência energética em unidades consumidoras “baixa renda”, que realiza na troca de refrigeradores antigos e ineficientes por refrigeradores novos com volume interno de armazenamento de 300 litros e Selo Procel classe A no consumo de energia elétrica, a substituição de lâmpadas incandescentes por lâmpadas fluorescentes compactas de 20W e a economia de energia de uma edificação residencial com a melhoria da sua envoltória. Desta forma, foi modelada uma edificação tipo no EnergyPlus, e realizada a simulação com o refrigerador e lâmpadas, antes e após o processo de substituição, para estimativa do consumo de energia elétrica ativa e da demanda de potência ativa. Com base nesta estimativa de redução de consumo e de demanda, foi calculada a relação Custo-Benefício do projeto pela simulação computacional e pelo método convencional, estipulado pelo Manual de Eficiência Energética da Aneel. Foi determinado o nível de eficiência energética de uma casa popular tipo, segundo o Método Prescritivo do Regulamento Técnico da Qualidade para o Nível de Eficiência Energética de Edificações Residenciais (RTQ-R). Também foi proposta uma nova modalidade de projeto de eficiência energética voltada para a melhoria da envoltória de residências, avaliando o impacto na redução do consumo e demanda de potência ativa e sua relação Custo-Benefício. / In electrical efficiency projects , which involves the exchange of conventional equipment with efficient , there is the difficulty of estimating the consumption of active power and active power demand before and after project implementation . However , EnergyPlus software has proven an effective tool for simulations energy term , allowing portray the systems evaluated with very close to the real system operation. Given the significant increase and the consequent need to control the power consumption by the residential sector , this paper proposes to analyze the technical and economic feasibility of the project on energy efficiency in consumer units "low income " , which performs the exchange of old and inefficient refrigerators for with new internal storage volume of 300 liters and Procel class A in energy consumption , replacing incandescent bulbs with compact fluorescent lamps and 20W energy saving of a residential building with improved envelope their refrigerators . Thus , one type building was modeled in EnergyPlus , and performed the simulation with the cooler and lamps before and after the replacement process for estimating consumption of active power and active power demand . Based on this estimated reduction of consumption and demand, the cost - benefit ratio of the project by computer simulation and by the conventional method stipulated by the Energy Efficiency Manual Aneel was calculated . The level of energy efficiency of a popular house type was determined according to the Prescriptive Method Quality Technical Regulation for the Level of Energy Efficiency of Residential Buildings (RTQ-R) . A new type of energy efficiency project aimed at improving the envelope of residences were also proposed for assessing the impact on reducing consumption and demand of active power and its cost-effectiveness .
3

Effectiveness of varied refugia configurations for the genetically modified maize (Zea mays L.) in Kwa-Zulu-Natal midlands

Moodley, Odeshnee 11 1900 (has links)
Genetically modified (GM) white and yellow maize, Zea mays, has been commercially released and cultivated in South Africa since 1997/1998. The traits expressed are insect resistance and herbicide tolerance conferred by the bacteria Bacillus thuringiensis (Bt) Cry genes and Agrobacterium 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase gene, respectively. The Cry genes have been used widely to control lepidopteran insect pests but insect resistance to GM Bt crops has been a concern since the introduction of this technology. A management strategy includes refugia planting of 5% non-Bt plants, with no insecticide application, and 20%, where insecticide application is allowed. These refugia are designed to allow the survival of insect pests within restricted planted zones. However, in South Africa there are reports of Bt-resistant stem borer (Busseola fusca) (Fuller) (Lepidoptera: Noctuidae) and non-compliance with refuge planting. The aims of this study were two-fold: 1. To conduct a survey among KwaZulu-Natal (KZN) GM maize growers to ascertain information such as level of compliance with refuge planting and to determine which refugia were predominantly planted and reasons thereof; 2. To conduct a replicated field trial to determine yield, insect borer damage and economic benefit of the 5% unsprayed and 20% sprayed refuge options (including three configurations namely strip, perimeter and block and a 5 and 20% ‘refuge-in-a-bag’ option). The survey indicated that 28 out of 29 (96.6%) KZN Bt maize growers plant the 5% non-sprayed refuge with 27 (96.4%) of those respondents planting the strip configuration for the purpose of insect management (75%) and ease of planting (32.2%). The survey also showed that 7 (seven) i.e. 21.9% of KZN Bt maize growers observed borer damage and although growers are now fully compliant with refugia planting requirements, initially 7 respondents (24.1%) did not comply with or plant refugia correctly. Furthermore, 7 respondents reported insect borer damage in their maize with 4 of the 7 instances (57.1%) likely stemming from incorrectly planted refugia. vii No significant differences in yield or insect damage were observed between the 5 and 20% refugia for any of the planting configurations in the field trial. However due to costs involved with insecticide application and labour required for the operation in the 20% option, these treatments were less economically advantageous than the non-Bt control. The 20% block and strip configurations had a cost benefit ratio of ZAR 7.21 and ZAR 6.67 respectively, earned per R1 spent by the grower compared with ZAR 7.76 in the sprayed control. The cost-benefit comparison for the 5% block and strip configurations was ZAR 8.48 and ZAR 7.71, respectively compared with ZAR 9.44 in the unsprayed control. In addition, the 20% seed mixture limited borer damage to 4.95% when compared with 15.77% damage in the sprayed control (ANOVA, F pr = 0.124). The seed mixtures are not available commercially and the results from the survey indicated that some education and marketing by the seed companies would be advisable prior to their release to the farming community. In order to determine which of the refuge options between 5 and 20% would be more advantageous for growers overall, regardless of the planting configuration; data were grouped and analysed. There were no significant differences in either the yield or insect damage for the 5 and 20% refugia, but the cost-benefit calculations indicated that the 5% option was more cost effective – for the 5 and 20% refugia, ZAR 7.97 and ZAR 7.15 respectively, earned per ZAR 1 spent by the grower (ANOVA, F pr. = 0.03). This is because no insecticide was used in the 5% treatments. Mean ear damage comparisons between the 5 and 20% refugia showed that the 20% refuge in the perimeter configuration incurred the least damage (2.65% ear damage) compared with 5% perimeter (10.86% ear damage), although the reasons for this are not clear. While the results of the field trials showed no significant differences in insect damage and yield with regard to choice of refuge configuration, monitoring insect resistance management remains an integral part of Bt maize crops in South Africa, in order to delay further resistance development and to prolong the viability of Bt technology. / Agriculture and  Animal Health / M. Sc. (Agriculture)
4

The techno-economics of bitumen recovery from oil and tar sands as a complement to oil exploration in Nigeria / E. Orire

Orire, Endurance January 2009 (has links)
The Nigeria economy is wholly dependent on revenue from oil. However, bitumen has been discovered in the country since 1903 and has remained untapped over the years. The need for the country to complement oil exploration with the huge bitumen deposit cannot be overemphasized. This will help to improve the country's gross domestic product (GDP) and revenue available to government. Bitumen is classifled as heavy crude with API (American petroleum Institute) number ranging between 50 and 110 and occurs in Nigeria, Canada, Saudi Arabia, Venezuela etc from which petroleum products could be derived. This dissertation looked at the Canadian experience by comparing the oil and tar sand deposit found in Canada with particular reference to Athabasca (Grosmont, Wabiskaw McMurray and Nsiku) with that in Nigeria with a view of transferring process technology from Canada to Nigeria. The Nigeria and Athabasca tar sands occur in the same type of environment. These are the deltaic, fluvial marine deposit in an incised valley with similar reservoir, chemical and physical properties. However, the Nigeria tar sand is more asphaltenic and also contains more resin and as such will yield more product volume during hydro cracking albeit more acidic. The differences in the components (viscosity, resin and asphaltenes contents, sulphur and heavy metal contents) of the tar sands is within the limit of technology adaptation. Any of the technologies used in Athabasca, Canada is adaptable to Nigeria according to the findings of this research. The techno-economics of some of the process technologies are. x-rayed using the PTAC (petroleum technology alliance Canada) technology recovery model in order to obtain their unit cost for Nigeria bitumen. The unit cost of processed bitumen adopting steam assisted gravity drainage (SAGD), in situ combustion (ISC) and cyclic steam stimulation (CSS) process technology is 40.59, 25.00 and 44.14 Canadian dollars respectively. The unit cost in Canada using the same process technology is 57.27, 25.00 and 61.33 Canadian dollars respectively. The unit cost in Nigeria is substantively lesser than in Canada. A trade off is thereafter done using life cycle costing so as to select the best process technology for the Nigeria oil/tar sands. The net present value/internal rate of return is found to be B$3,062/36.35% for steam assisted gravity drainage, B$I,570124.51 % for cyclic steam stimulation and B$3,503/39.64% for in situ combustion. Though in situ combustion returned the highest net present value and internal rate of return, it proved not to be the best option for Nigeria due to environmental concern and response time to production. The best viable option for the Nigeria tar sand was then deemed to be steam assisted gravity drainage. An integrated oil strategy coupled with cogeneration using MSAR was also seen to considerably amplify the benefits accruable from bitumen exploration; therefore, an investment in bitumen exploration in Nigeria is a wise economic decision. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2010.
5

The techno-economics of bitumen recovery from oil and tar sands as a complement to oil exploration in Nigeria / E. Orire

Orire, Endurance January 2009 (has links)
The Nigeria economy is wholly dependent on revenue from oil. However, bitumen has been discovered in the country since 1903 and has remained untapped over the years. The need for the country to complement oil exploration with the huge bitumen deposit cannot be overemphasized. This will help to improve the country's gross domestic product (GDP) and revenue available to government. Bitumen is classifled as heavy crude with API (American petroleum Institute) number ranging between 50 and 110 and occurs in Nigeria, Canada, Saudi Arabia, Venezuela etc from which petroleum products could be derived. This dissertation looked at the Canadian experience by comparing the oil and tar sand deposit found in Canada with particular reference to Athabasca (Grosmont, Wabiskaw McMurray and Nsiku) with that in Nigeria with a view of transferring process technology from Canada to Nigeria. The Nigeria and Athabasca tar sands occur in the same type of environment. These are the deltaic, fluvial marine deposit in an incised valley with similar reservoir, chemical and physical properties. However, the Nigeria tar sand is more asphaltenic and also contains more resin and as such will yield more product volume during hydro cracking albeit more acidic. The differences in the components (viscosity, resin and asphaltenes contents, sulphur and heavy metal contents) of the tar sands is within the limit of technology adaptation. Any of the technologies used in Athabasca, Canada is adaptable to Nigeria according to the findings of this research. The techno-economics of some of the process technologies are. x-rayed using the PTAC (petroleum technology alliance Canada) technology recovery model in order to obtain their unit cost for Nigeria bitumen. The unit cost of processed bitumen adopting steam assisted gravity drainage (SAGD), in situ combustion (ISC) and cyclic steam stimulation (CSS) process technology is 40.59, 25.00 and 44.14 Canadian dollars respectively. The unit cost in Canada using the same process technology is 57.27, 25.00 and 61.33 Canadian dollars respectively. The unit cost in Nigeria is substantively lesser than in Canada. A trade off is thereafter done using life cycle costing so as to select the best process technology for the Nigeria oil/tar sands. The net present value/internal rate of return is found to be B$3,062/36.35% for steam assisted gravity drainage, B$I,570124.51 % for cyclic steam stimulation and B$3,503/39.64% for in situ combustion. Though in situ combustion returned the highest net present value and internal rate of return, it proved not to be the best option for Nigeria due to environmental concern and response time to production. The best viable option for the Nigeria tar sand was then deemed to be steam assisted gravity drainage. An integrated oil strategy coupled with cogeneration using MSAR was also seen to considerably amplify the benefits accruable from bitumen exploration; therefore, an investment in bitumen exploration in Nigeria is a wise economic decision. / Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2010.
6

Effectiveness of varied refugia configurations for genetically modified maize (Zea mays L.) in KwaZulu-Natal midlands

Moodley, Odeshnee 11 1900 (has links)
Genetically modified (GM) white and yellow maize, Zea mays, has been commercially released and cultivated in South Africa since 1997/1998. The traits expressed are insect resistance and herbicide tolerance conferred by the bacteria Bacillus thuringiensis (Bt) Cry genes and Agrobacterium 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase gene, respectively. The Cry genes have been used widely to control lepidopteran insect pests but insect resistance to GM Bt crops has been a concern since the introduction of this technology. A management strategy includes refugia planting of 5% non-Bt plants, with no insecticide application, and 20%, where insecticide application is allowed. These refugia are designed to allow the survival of insect pests within restricted planted zones. However, in South Africa there are reports of Bt-resistant stem borer (Busseola fusca) (Fuller) (Lepidoptera: Noctuidae) and non-compliance with refuge planting. The aims of this study were two-fold: 1. To conduct a survey among KwaZulu-Natal (KZN) GM maize growers to ascertain information such as level of compliance with refuge planting and to determine which refugia were predominantly planted and reasons thereof; 2. To conduct a replicated field trial to determine yield, insect borer damage and economic benefit of the 5% unsprayed and 20% sprayed refuge options (including three configurations namely strip, perimeter and block and a 5 and 20% ‘refuge-in-a-bag’ option). The survey indicated that 28 out of 29 (96.6%) KZN Bt maize growers plant the 5% non-sprayed refuge with 27 (96.4%) of those respondents planting the strip configuration for the purpose of insect management (75%) and ease of planting (32.2%). The survey also showed that 7 (seven) i.e. 21.9% of KZN Bt maize growers observed borer damage and although growers are now fully compliant with refugia planting requirements, initially 7 respondents (24.1%) did not comply with or plant refugia correctly. Furthermore, 7 respondents reported insect borer damage in their maize with 4 of the 7 instances (57.1%) likely stemming from incorrectly planted refugia. vii No significant differences in yield or insect damage were observed between the 5 and 20% refugia for any of the planting configurations in the field trial. However due to costs involved with insecticide application and labour required for the operation in the 20% option, these treatments were less economically advantageous than the non-Bt control. The 20% block and strip configurations had a cost benefit ratio of ZAR 7.21 and ZAR 6.67 respectively, earned per R1 spent by the grower compared with ZAR 7.76 in the sprayed control. The cost-benefit comparison for the 5% block and strip configurations was ZAR 8.48 and ZAR 7.71, respectively compared with ZAR 9.44 in the unsprayed control. In addition, the 20% seed mixture limited borer damage to 4.95% when compared with 15.77% damage in the sprayed control (ANOVA, F pr = 0.124). The seed mixtures are not available commercially and the results from the survey indicated that some education and marketing by the seed companies would be advisable prior to their release to the farming community. In order to determine which of the refuge options between 5 and 20% would be more advantageous for growers overall, regardless of the planting configuration; data were grouped and analysed. There were no significant differences in either the yield or insect damage for the 5 and 20% refugia, but the cost-benefit calculations indicated that the 5% option was more cost effective – for the 5 and 20% refugia, ZAR 7.97 and ZAR 7.15 respectively, earned per ZAR 1 spent by the grower (ANOVA, F pr. = 0.03). This is because no insecticide was used in the 5% treatments. Mean ear damage comparisons between the 5 and 20% refugia showed that the 20% refuge in the perimeter configuration incurred the least damage (2.65% ear damage) compared with 5% perimeter (10.86% ear damage), although the reasons for this are not clear. While the results of the field trials showed no significant differences in insect damage and yield with regard to choice of refuge configuration, monitoring insect resistance management remains an integral part of Bt maize crops in South Africa, in order to delay further resistance development and to prolong the viability of Bt technology. / Agriculture and  Animal Health / M. Sc. (Agriculture)

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