This is an exploratory study. Its purpose is to delineate and identify the important factors influencing land use in Malaya during the period 1947 to I960. Since the subject of land use is very wide our aim is to deal only with agricultural land use. Other uses are discussed only incidentally or as they are involved in the shifting uses of land. The scope and nature of land use patterns in Malaya as in other countries, is a reflection of economic, geographical and political factors. Land use usually reflects the operation of the principle of comparative advantage. Theoretically different types of land would normally be put to their best uses and any instability which exists would be cleared up by the market mechanism. Institutional barriers often impede this development as we show in the Malayan case. Two conflicts are apparent in the land use policies in Malaya. The first is between rubber and rice; that is, whether to specialise in the production of rubber, over which Malaya has a comparative advantage, or to produce rice for subsistence over which Malaya does not have a comparative advantage. Of course the rational course from an economic point of view is to produce more rubber. But more than economics are involved in such issues. The other conflict is whether to produce rubber on estates, which are the large scale enterprises, or on smallholdings, which are the peasant, small scale enterprises. Again more than economics, are involved. In this study attention is focussed primarily on the rubber-rice land use pattern. Even then rubber gets most of the attention. Technical questions especially those relating to rubber are of considerable interest but these are discussed only insofar as they have general economic relevance. The study as a whole can be divided into three parts. Chapters I and II comprise the first section. The opening chapter contains the economic and historical background to the land use patterns in Malaya and points out the rubber-rice land use pattern. In Chapter II we discuss the theoretical, suggested effects of the dual pattern of land utilisation. An attempt is also made to apply the dualistic theories of economic growth to Malaya in order to ascertain whether the conclusions of these theorists are verified in Malaya. The second section comprises of Chapter III. Here we discuss the obstacles to good land utilisation in the post war period. The third major section takes up the remaining chapters, all of which deal largely with rubber, which is one of the mainstays of the Malayan economy. In Chapter IV we discuss the relative efficiency of estates and smallholdings as producers of rubber. This chapter may be said to contain the heart of the matter since it helps us to evaluate two recent developments, which are discussed in Chapters V and VI. Chapter V, the "break-up" of rubber estates, discusses the various aspects of estates which have been diminishing in size. The most important effect of this is the creation of smallholdings and a loss in government revenue. The second recent development, the land development schemes initiated by the government, is discussed in Chapter VI. Here again the chief effect is the creation of rubber smallholdings. The concluding chapter has the twofold aim of summarising the main findings to this study and of setting out briefly the possible future trends of land use in Malaya. / Arts, Faculty of / Vancouver School of Economics / Graduate

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Master of Science / Rubber is a widely used material globally and undergoes significant changes as it ages. However, the specific consequences of rubber aging on tires and vehicle dynamics remain a relatively underexplored domain. This study delves into the effects of rubber aging on tires and motorcycle dynamics. A Dynamical Mechanical Analysis (DMA) test was performed to study the effect of rubber aging combined with computer simulation models to predict how much the rubber wears out over time. It was found that as rubber gets older it doesn't wear out much faster. This might be because the changes in the rubber properties as it ages are very small. The rubber material also gets stiffer as it ages, leading to minimal differences in the wear rate. The Magic Formula (MF) model was used in this study to model motorcycle tires. A 3-4% increase in the longitudinal and lateral tire forces was observed as the tire aged. This was followed by simulations to study the motorcycle behavior during straight-line and turning motion. It was found that the front tires of the motorcycle had an approximately 3% change in the forces experienced, while the forces experienced by the rear tires only changed by 1-2% with respect to aging. These results are similar to the results obtained by other researchers on the effects of rubber aging on car performance. Thus, this study stresses the importance of understanding how tires change over time and how that affects how motorcycles perform.

A literature review of rubber-bearing plants in the United States was made, and the essentials of distribution, ecology and rubber content presented in condensed form. Filed lettuce of the specie Lactuca scariola was investigated to determine its place among the other rubber-bearing plants. Nearly pure stands of natural growing wild lettuce were harvested and the weights of plant material determined. Yields up to 2,830 pounds of dry leaves together with 5,760 pounds of dry stems per acre were obtained. The seasonal variation in rubber content and resins of one natural growing wild lettuce stand was studied from the time of the appearance of flower buds to the end of the growth cycle. At this time of maximum rubber content of this stand the calculated yield was between 1.16 and 1.57 pounds of rubber per acre. An experimental planting was undertaken to determine rubber content, resin content, and growth and cultivation characteristics of the earlier stages of growth. Young plants gave up to 0.339 percent rubber and a calculated yield of 13.7 pounds of rubber per acre. Drying temperatures up to the 180°F gave no decreases in rubber content during drying. The rubber content of harvested plants was found to decrease rapidly on exposure to sunlight. At least 10.7 percent of the seeds were found to have the power of germinating soon after ripening. Seeds ripened in the fall were found to have between 49 and 68 percent germinating power. / Master of Science

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A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2014. / This study concentrated on two main thrusts: 1) the optimal synthesis and characterisation of various micro- and nanosized carbon materials and 2) a comparative investigation of the capabilities of these carbonaceous materials to reinforce a locally available styrene butadiene rubber (SBR), which was commonly used to make car tyres. In the former case, a range of carbon materials including nitrogen doped/undoped carbon nanotubes as well as carbon microspheres (CMSs) were successfully synthesized by two different techniques (i.e. chemical vapour deposition (CVD) and hydrothermal synthesis). These were then fully characterised by numerous techniques which included: TEM, TGA, FTIR, PXRD, laser Raman spectroscopy, Zeta potential measurements and BET surface area analysis. In the latter case, these micro and nanocarbon materials were systematically added to SBR at various loadings (ranging from 0.125–0.500% (m/m)). Here the tensile strengths of the resultant composites, loaded with these various micro and nanocarbon materials, were measured for comparison to establish which (if any) was the best reinforcement material for SBR. Results obtained from the tensile strength measurements of the variously loaded SBR composites, showed that irrespective of the method of synthesis (i.e. CVD or hydrothermal synthesis) carbon microspheres (undoped, doped, functionalised or unfuntionalised) performed more poorly as fillers than carbon nanotubes. Furthermore the results obtained, from the various characterisation techniques mentioned previously, indicated that the lower performance of these microspheres as fillers may have been due to their: size, shape and low surface areas. By contrast when the tensile strengths of SBR reinforced with either CNTs or NCNTs were measured, the former outperformed the latter as fillers. It was speculated, based upon the data obtained, that NCNTs were poorer fillers than CNTs due to their higher negative surface charges, larger diameters and lower crystallinity. Hence this study has shown that low loadings (i.e. 0.250 % (m/m)) of the correctly matched type of carbonaceous material can significantly enhance the tensile strength and Young’s modulus of a locally available styrene butadiene rubber.