This thesis is written with the intention to help establish the fact that there are definite advantages to be claimed from the use of statistical quality control in the foundry industry. / Master of Science

Call number: LD2668 .T4 1984 B58 / Master of Science

Call number: LD2668 .T4 1986 F86 / Master of Science / Mechanical and Nuclear Engineering

Thesis (M. Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2021 / Small-scale farmers are the drivers of many countries in Africa and play an important role in livelihood creation among the poor in rural areas (DAFF, 2012). The efficient use of scarce resources in promoting agricultural production has encouraged a considerable amount of research in determining efficiency differentials of small-scale farmers (Chiona, 2011); especially those engaged in maize as a staple commodity in many parts of the world. The study examined the effect of access to tractor service on technical efficiency of small-scale maize farmers following the implementation of the Masibuyele Emasimini programme in the Mpumalanga province. The objectives of the study were to: (i) Compare and identify the socio-economic characteristics of small-scale maize farmers in the three selected districts of the study, (ii) analyse the socio-economic factors influencing small-scale maize farmers’ access to tractor service, and to (iii) measure technical efficiency of farmers who have access to tractor service. The data collection was carried out in three districts of the Mpumalanga province, that is, Ehlanzeni, Nkangala and Gert Sibande. Farmers producing maize were purposively selected for the study because maize is the most staple food produced in the province, especially on a small-scale level. To effectively cover the study area, a simple random technique was used for sampling with a semi-structured questionnaire administered to 101 farmers. The three districts are heterogeneous in technical aspects, and were therefore treated separately in terms of data collection, analysis and report of findings. The data were further analysed using descriptive statistics, the logistic regression and Cobb-Douglas production function model to address objective one, two and three mentioned above, respectively. The results of the logistic regression model indicated that out of the 9 (Nine) socio-economic variables included in the analysis, 6 (Six) of them (Farmer’s association, irrigation, farmer’s level of education, gender, ownership of land and household size) were found to be significant and influencing access to v tractor service by small-scale maize farmers. Technical efficiency levels revealed that farmers with access to tractor service were more technically efficient than those without access in all districts of the Mpumalanga province. For example, the average technical efficiency for small-scale farmers with access to tractor service in the Ehlanzeni district was 0.68; about 41% higher than those without access with an average technical efficiency of about 0.27. The Cobb-Douglas results on the other hand, revealed that farmers in the Mpumalanga province are experiencing technical inefficiency in maize production due to decreasing returns to scale. Access to tractor service was also negatively insignificant towards maize production in both the Ehlanzeni and Nkangala district, and was found to have a positive but insignificant effect in Gert Sibande. Policy implications are that to improve the efficiency of tractor service (rendered by the Masibuyele Emasimini programme) towards maize production; government should focus on significant factors influencing the access of the following by small-scale maize farmers and the factors are machinery, irrigation, gender, and ownership of land, farmer’s level of education, farmer’s association, and household and land size per district. / National Research Foundation (NRF)

Agriculture consistently ranks as one of the most dangerous occupations based on an overall work death rate. Tractor overturns, by far the single largest cause of death on farms, account for approximately 19% of all on-farm deaths. The concept of a Roll-over Protective Structure (ROPS) came into existence in 1971 and is designed to form a protection zone for the operator. However, the only way that the operator will stay in the zone is by using a seatbelt or other restraint system. A survey on tractor seatbelt usage was undertaken. Results indicate that only 13% of operators wear seatbelts half or more of the time and 61% report never wearing one. The reasons for these practices are a combination of factors: too much inconvenience, time consuming, an old habit of not wearing one, and a feeling that there is no danger. However, even in the face of such negativity, the survey revealed that 65% of the operators were neutral or approved of the idea of an automatically closing seatbelt. An automatically closing restraint system prototype was designed and built. The system was found to be costly ($560.00) and the potential for mass retrofitting was found to be very limited. However, an automatically closing seatbelt seems to be a viable solution to the problem of operators being unwilling to use the seatbelts provided. / Master of Science

Call number: LD2668 .T4 1979 G63 / Master of Science

Call number: LD2668 .T4 1979 P32 / Master of Science

No description available.

Orientador: João Eduardo Guarnetti dos Santos / Banca: Andre Luiz Andreoli / Banca: Ricardo Carvalho Tosin / Resumo: O futuro do fornecimento de alimentação para uma população global crescente, requerem a necessidade da expansão da agroindústria. Esse crescimento da demanda por produtos agrícolas é reflete na mecanização intensiva do setor agrícola. Nesse contexto, o objetivo do trabalho é avaliar a vibração ocupacional no assento do operador de oito tratores agrícolas com o motor funcionando em marcha lenta e em rotação de trabalho e verificar se estão dentro dos limites estabelecidos pelos critérios da EU-OSHA (Agência Europeia para a Segurança e Saúde no Trabalho) e pela sua diretiva 44/EC, publicada em 22 de junho de 2002 caracterizando o trabalho como insalubre ou não. O presente trabalho foi realizado no Núcleo de Ensaio de Máquinas e Pneus Agroflorestais (NEMPA), localizado nas dependências da Faculdade de Ciências Agronômicas (FCA/UNESP), câmpus de Botucatu - SP. Os ensaios foram todos conduzidos em superfície de cimento plana e de modo estático, ou seja, os tratores não foram avaliados em movimento. Foram avaliados oito tratores de marcas, modelos e potência nominal no motor diferentes, alguns com cabine e outros sem. A coleta dos dados nas máquinas foi feita utilizando um dosímetro de vibração da marca Larson Davis modelo HVM100 e foi utilizado o software Blaze®, que acompanha o dosímetro para análise dos dados. A vibração foi avaliada utilizando uma almofada com acelerômetro triaxial (seat pad) também devidamente calibrada. Os tratores foram analisados com o motor em marcha lenta e em rotação de trabalho. O delineamento experimental empregado foi inteiramente casualizado, já que a mesma condição foi mantida para todos os tratamentos, os valores coletados na base e no encosto do assento foram somados e foi feita uma média entre eles e esta será considerada como a vibração total que chega até o assento. Os valores coletados foram submetidos a uma ... / Abstract: The future of food supply for a growing global population, require the necessity of expansion of agribusiness. This growing demand for agricultural products is reflected in the intensive mechanization of the agricultural sector. In such context, this study aimed to evaluate the vibration in the operators' seat of eight agricultural tractors and determine whether they are within the limits established on the criteria of EU-OSHA (European Agency for Safety and Health at Work) and their directive 44 / EC published in June 22, 2002 featuring the work as unhealthy or not. This work was performed at NEMPA located on the premises Faculty of Agricultural Sciences (FCA/UNESP), campus of Botucatu - SP. The tests were all conducted on a level cement surface and in static mode, that is, the tractors were not evaluated moving, have been evaluated eight tractor brands, models and different nominal power in the engine, some with and some without cabin. The data collection on the machines was made using a dosimeter of vibration of the brand Larson Davis HVM100 model and was used Blaze software that comes with the dosimeter, for data analysis. The vibration was evaluated using a pad with triaxial accelerometer (seat pad) as well calibrated properly. The tractors were evaluated with the engine at low idle and operating speed. The experimental design used was DIC since the same condition was kept for all treatments, the values collected the base and the back of the seat were summed and made a weighted average between them and this will be considered as the total vibration that reaches the seat. The collected data were submitted to an analysis of variance and the means compared by Tukey test at 5% probability. The evaluations conducted have shown that the greatest problems with vibration were found in tractors with power ratings up to 51kW in the engine, only at another tractor with 161kW in the engine was obtained ... / Mestre

Thesis(M.S.)--Auburn University, 2005. / Abstract. Includes bibliographic references.