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Bibliography: pages166-179. / Changes in the choice of technique in the harvesting and delivery of maize and weeding, the causes of these changes, and their consequences for employment and unemployment, were investigated. Data was collected for 61 farms in six magisterial districts of the Western Transvaal for the period 1968-1981. In 1968 about 30 percent of the crop was being harvested mechanically; by 1981, 95 percent. Sacks, in which almost half of total output was being delivered to depots in 1968, had, by 1977, been almost completely displaced by bulk handling. From 15 percent of the total crop area of 1968, weed sprays were being applied to 95 percent in 1981. There was an increase of about 75 percent in the average surface area of farms, and more than a doubling in the average yield per hectare. The greatest part of most of these changes occurred between 1973 and 1977. The causes of changes in the choice of technique were sought both in theory - neo-classical and historical-materialist - and in empirical evidence. A growing shortage of men but not of women, the convenience and controllability of combine-harvesting, and economies of scale generated by the increasing size of farms, were all important causes. But the cost advantage of mechanical over hand-harvesting on all except the smallest farms is what appears to have been crucial. For various reasons, this was not fully exploited until the middle '70s. Exogenous developments in technology, rather than changes in relative factor prices, should be seen as the fundamental cause of changes in harvesting techniques. Seasonal workers were still employed to glean after combine-harvesting and to hoe spray-resistant weeds, but whereas in the late '60s seasonal harvesting teams consisted typically of a comparatively large number of workers from black rural areas, mainly adults - women in the majority - and a few children, by the late '70s they were composed of a comparatively small number, most of whom were the wives and children of permanent farm workers, living on white farms. Between 1968 and 1981, the number of seasonal jobs per 1 000 hectares of maize fell by about 70 percent in harvesting and delivery, and by 60 percent in weeding. Rough estimates show total seasonal employment to have fallen from about 105 000 to 43 000 annually, the mechanization of reaping being the most important single cause. The employment of permanent workers in harvesting and delivery declined by almost 50 percent per 1 000 hectares, enabling the total number of workers to contract from about 30 000 in 1969 to 25 000 in 1976. Since 1977 employment patterns have stabilized. Though few men appear to have become unemployed because of changes in technology, women from black rural areas, chiefly in Bophuthatswana, have generally not been able to find other jobs. The real wages of permanent workers rose by 150 percent between 1970 and 1981, while those of seasonal workers increased only marginally. Changes in both wage and employment patterns have greatly narrowed the distribution of agricultural income.

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Harvesting is typically one of the largest cost components within a plantation forest rotation. A large proportion of New Zealand’s future harvest will be on steep terrain. Currently steep terrain harvesting is characterised by lower productivity and higher cost. It also has higher levels of manual or motor manual tasks such as setting chokers or tree felling, with a corresponding higher safety risk. The utilisation of ground-based machines on steep terrain has the potential to decrease harvest costs and improve safety. There is currently a push in New Zealand to increase the operating range. This is being done with a poor understanding of the slopes on which machines are currently operating and little understanding of the new risks steeper slopes might introduce. To better understand the true range of slopes on which forest machines are operating, a digital accelerometer was attached to 22 forest machines and provided real-time measurements of slope. The evaluated machines were grouped into one of four machine types; felling (n=4), shovelling (n=5), skidder (n=9) or European (n=4). The machine types were then analysed with respect to their machine slope (actual) and terrain slope (predicted) based on a digital terrain map. Two methods of calculating terrain slope were used, method one was based on a triangular irregular network (TIN) file with method two based off a raster file. Linear regression indicated that there was a relationship between machine slope and terrain slope for all four machine types, with the exception of European based machines, using the TIN method of slope calculation. All variables showed a poor coefficient of determination with the highest adjusted R squared single variable explaining 17% of the variation. All machines operated on slopes that exceed the New Zealand approved code of practice guideline of 30% and 40% slope for wheeled and tracked machines respectively. New Zealand based machines were shown to exceed the guidelines for terrain slope much more frequently, and by a greater margin, than European based machines.

Risk management is developing branch, which deals with identification, measurement, analysis and regulation of risks in the organisation. The main goal of this work is to find out the most significant risks of the production process in the firm TESLA Jihlava, a.s., to financially evaluate and to minimalize these risks. The way to optimize these risks and to reduce of costs is the mechanisation of the production process in this firm.

The rising problems associated with construction such as decreasing quality and productivity, labour shortages, occupational safety, and inferior working conditions have opened the possibility of more revolutionary solutions within the industry. One prospective option is in the implementation of innovative technologies such as automation and robotics, which has the potential to improve the industry in terms of productivity, safety and quality. The construction work site could, theoretically, be contained in a safer environment, with more efficient execution of the work, greater consistency of the outcome and higher level of control over the production process. By identifying the barriers to construction automation and robotics implementation in construction, and investigating ways in which to overcome them, contributions could be made in terms of better understanding and facilitating, where relevant, greater use of these technologies in the construction industry so as to promote its efficiency. This research aims to ascertain and explain the barriers to construction automation and robotics implementation by exploring and establishing the relationship between characteristics of the construction industry and attributes of existing construction automation and robotics technologies to level of usage and implementation in three selected countries; Japan, Australia and Malaysia. These three countries were chosen as their construction industry characteristics provide contrast in terms of culture, gross domestic product, technology application, organisational structure and labour policies. This research uses a mixed method approach of gathering data, both quantitative and qualitative, by employing a questionnaire survey and an interview schedule; using a wide range of sample from management through to on-site users, working in a range of small (less than AUD0.2million) to large companies (more than AUD500million), and involved in a broad range of business types and construction sectors. Detailed quantitative (statistical) and qualitative (content) data analysis is performed to provide a set of descriptions, relationships, and differences. The statistical tests selected for use include cross-tabulations, bivariate and multivariate analysis for investigating possible relationships between variables; and Kruskal-Wallis and Mann Whitney U test of independent samples for hypothesis testing and inferring the research sample to the construction industry population. Findings and conclusions arising from the research work which include the ranking schemes produced for four key areas of, the construction attributes on level of usage; barrier variables; differing levels of usage between countries; and future trends, have established a number of potential areas that could impact the level of implementation both globally and for individual countries.

The graduation theses at the theme ,, The optimalisation of seting land machanisation at maintenance of melioration objects (waterwork) is described using methods of scheduled maintenance of melioration objects and setting the land mechanisation at this operations with their tools. The next part of graduation theses is discribed the choose of optimal alternace (variation) resolution manner of maintenance complience with legislature and promulgation 225/2002 Sb. The general references at recultivation water reservoir (pond) is set out with practical pictures on pond Beranov near by village Čakov.

The main theme of this piece of work is to assess the influence of small mechanisation for maintenance of grass areas; therefore this work includes the description of grass areas as well as the overview of small mechanisation for maintenance of grass areas. Two types of mowers working on different principles of cutting were chosen to make a comparison. This work presents the results of measurement taken on 2 experimental grass areas treated by chosen types of mowers. There are results of monitoring of agrobotanical groups reported (coverage of grasses, the juncaceae, the cyperaceae, the clovers, and herbs) and coverage of grasses is graphically depicted in this work. Different results of grass coverage were statistically evaluated and compared just as the dry matter yields. Appropriate treatment of grass areas (mowing, supplementary seeding) as well as appropriate cutting system of small grass areas was recommended.