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Despite the signing of the 2005 Sudan Comprehensive Peace Agreement that ended the two decades of South-North Sudan war; and the 2015 Agreement on the Resolution of the Conflict in South Sudan, to end the current civil war, armed conflicts persist in South Sudan. Two key inadequacies of the liberal peacebuilding model, applied to address modern conflicts in Africa and across the globe are its insistence on international justice instruments such as the International Criminal Court, and the failure to recognize the role of local approaches and to incorporate them into peacebuilding intervention policies. This has resulted in failures to address the grievances and bitterness of war affected people and to reconcile divided communities. This study examines the potential and limits of applying local approaches to post-conflict peacebuilding in South Sudan. Based on empirical data obtained through qualitative case study conducted in South Sudan over five months in 2016, the findings reveal that despite the wide use of local institutions and justice mechanisms, many challenges exist, that pose serious difficulties in solely applying these strategies to transitional justice. However, for the liberal peacebuilding model to address the root causes of internal conflicts and build sustainable peace, local strategies could provide a significant complementary contribution, since dealing with the past entails more than retribution and truth seeking. The study has wider implications in practical and theoretical considerations for ongoing armed conflicts in Africa and other parts of the world.

This thesis details the physical and electronic structure of several technologically important transition metal chalcogenides (TMCs) using a combination of transmission electron microscopy (TEM) and surface science experimental techniques. The materials studied include CuxTe and CdTe, which find application in high efficiency, low weight photovoltaic devices. CuxTe alloys are frequently used as an electrical back contact in high efficiency CdTe photovoltaics. Here, we examine the alloying of Te on the Cu(111), polycrystalline Cu and Cu(643) surfaces. Chapter 3 of this thesis shows that the alloying of Te and Cu(111) is facile at room temperature, contrary to previous reports. Two distinct surface phases exist, depending on Te surface concentration. Below a coverage of 0.33 monolayers (MLs) of Te a surface substitutional alloy (SSA) is found to exist, where a Te adatom substituted for a surface Cu atom. For Te coverages greater than 0.66 ML, an unusual Cu3Te2 alloy continually grows on the surface, stabilised by a good lattice match to the Cu(111) substrate. The surface alloying of the Cu-Te system displays an intriguing dependence on the surface termination of the Cu substrate. Of the three Cu substrates studied here, Cu(111), Cu(643)R and polycrystalline Cu, a 1 ML film of Te gave ordered alloy structures with stoichiometries of Cu3Te2, CuTe and Cu2Te, respectively. In chapter 4, the study of thin film photovoltaics is extended to the deposition of CdTe onto Cu and CuxTe substrates. CdTe is observed to grow three dimensionally on Cu(111), Cu3Te2 and Cu2Te. Cu+ diffusion, crucial for photovoltaic performance, is detected for CdTe thicknesses greater than 2 ML and is assigned, predominately, to Cu2Te crystallites forming within the CdTe layer, with a minor amount of Cu residing in interstitial sites in the host CdTe structure. Chapter 5 describes the alloying of Te with a intrinsically chiral surface, Cu(643)R, the first study of its kind. The results of this study reveal that step mediated alloying occurs between Cu and Te with significant faceting of the surface. Two ordered CuTe alloy phases were observed for sub-monolayer Te coverages. The low coverage alloy exists for Te coverages between 0.18 ML and 0.45 ML and has a chiral unit cell. The high coverage alloy exists for Te coverages between 0.45 ML and 1.5 ML and has an achiral unit cell. The atomic positions of these surface alloys are tentatively interpreted from the scanning tunnelling microscopy (STM) images. In contrast to the thin film experiments in chapters 3-5, chapter 6 describes a study of TaS3 nanoribbons. These studies reveal that the nanoribbons have a distinct core-shell type structure. Characterisation with surface science techniques shows that the shell is nonstoichiometric and amorphous while TEM shows a crystalline core to the material. Interestingly, the TaS3 are observed to be unstable when interfaced on a Au substrate, with the shell persistently losing S to the substrate, which have potential implications in device integration.

This thesis is concerned with the inventory control of items that can be considered independent of one another. The decisions when to order and in what quantity, are the controllable or independent variables in cost expressions which are minimised. The four systems considered are referred to as (Q, R), (nQ,R,T), (M,T) and (M,R,T). Wiith ((Q,R) a fixed quantity Q is ordered each time the order cover (i.e. stock in hand plus on order ) equals or falls below R, the re-order level. With the other three systems reviews are made only at intervals of T. With (nQ,R,T) an order for nQ is placed if on review the inventory cover is less than or equal to R, where n, which is an integer, is chosen at the time so that the new order cover just exceeds R. In (M, T) each order increases the order cover to M. Fnally in (M, R, T) when on review, order cover does not exceed R, enough is ordered to increase it to M. The (Q, R) system is examined at several levels of complexity, so that the theoretical savings in inventory costs obtained with more exact models could be compared with the increases in computational costs. Since the exact model was preferable for the (Q,R) system only exact models were derived for theoretical systems for the other three. Several methods of optimization were tried, but most were found inappropriate for the exact models because of non-convergence. However one method did work for each of the exact models. Demand is considered continuous, and with one exception, the distribution assumed is the normal distribution truncated so that demand is never less than zero. Shortages are assumed to result in backorders, not lost sales. However, the shortage cost is a function of three items, one of which, the backorder cost, may be either a linear, quadratic or an exponential function of the length of time of a backorder, with or without period of grace. Lead times are assumed constant or gamma distributed. Lastly, the actual supply quantity is allowed to be distributed. All the sets of equations were programmed for a KDF 9 computer and the computed performances of the four inventory control procedures are compared under each assurnption.

The islands and nations of the Caribbean are beset by numerous problems which retard economic development. Most critical of these problems are limited natural resources, a heavy dependence on monoculture, backward agricultural practices and high population densities. Although the Dominican Republic shares these problems with neighboring islands and countries, this nation has exerted considerable efforts toward strengthening its economy. This study examines the Dominican Republic geographically with particular emphasis on the nation's ability to develop its economy and to achieve a standard of living hitherto unknown among other tropical agrarian economies of the Caribbean. The Dominican Republic occupies the eastern two-thirds of the island of Hispaniola. This island lies at the convergence of two major cordillera axes of the West Indies and is the most rugged island of the Greater Antilles. In general, the mountains tend in an east to west direction with the Cordillera Central dominating the island and extending nearly the entire length of the country. Mountainous terrain covers approximately 60 per cent of the nation's area. Of remaining level lands the most important are the Cibao Valley north of the Cordillera Central and the South Coastal Plain which occupies the eastern two-thirds of the country south ot this cordillera. Easterly trade winds dominate the climate, which generally is warm and humid. Heaviest rainfall occurs in the northeast where a tropical rainforest is found. Southern and western sections of the country exhibit a savanna type of climate with maximum precipitation coming in the period of high insolation. The north coast also has a savanna climate, but maximum rainfall there comes in the winter months. The southwestern corner of the country, while basically having a savanna climate, is drier than other areas and certain sections are sub-humid. In spite of these climatic conditions of generally abundant rainfall and warm temperatures which favor agriculture, centuries of neglect, corruption, revolutions and wars hindered the development of a sound agricultural policy. When the Trujillo regime gained control of the country in 1930 measures were instituted to improve the farm economy. Irrigation projects in sub-humid western areas, agricultural colonies to settle these areas, and land distribution among hitherto landless peasants were the major aspects of the overall agricultural program. Principal aims of this program were the diversification of agricultural exports and a greater self-sufficiency in domestic foodstuffs. Attaimnent of these two goals has met with a fair degree of success. Heavy dependence on the export of sugar for national revenue has been reduced and this crop now is strongly supported by coffee and cacao. Although the country still imports large quantities of foodstuffs, the Republic's farms have reduced these imports from 27 per cent of all imports in 1929 to 10.5 per cent in 1954 without any reduction in domestic consumption. At the same time, exports of certain foodstuffs have been possible and the nation has the potential to become an important exporter of foodstuffs to neighboring Caribbean areas. This overall agricultural program has created a farm economy pattern. that is reflected in the nation's six major agricultural regions. These are the commercial sugar cane belt of the South Coastal Plain, the coffee and cacao belt of the eastern Cibao Valley, mixed commercial and subsistence agriculture of the central Cibao Valley , irrigated rice lands of the western Cibao Valley, mixed farming and grazing lands of the western interior valleys, and irrigated sugar cane of the Enlriquillo Basin. In conjunction with the program of agriculture there has been a policy of industrial expansion predicated on the development of industries utilizing the nation's natural resources. A general lack of minerals and fuels precluded heavy industry and the main emphasis has been on light industries engaged in processing the products of agriculture. Thus today the processing of agricultural products accounts for 80 per cent of sales in Dominican industry, with the crops of commercial agriculture contributing most heavily. Other significant categories of the Dominican industrial complex are textiles, the extraction and processing of metallic and non-metallic minerals, and chemicals. Although ranking far behind agricultural processing with respect to the national economy, these industries have a potential for future expansion. Perhaps the brightest prospect lies within the chemical industry. The nation possesses large reserves of salt which hardly have been exploited. A gradual development of chemical industries built around salt would appear to be a wise policy for the future. All told, the expansion of industry since 1936 has been impressive. The number of employees has increased by 300 per cent, the number of industrial establishments by 300 per cent; the invested capital by 250 per cent and the value of sales by 1,000 per cent. In spite of the progress made since 1930 in revitalizing the nation's economy, succeeding years will continue to be critical if the nation is to realize its economic potential. Although programs for agriculture have enhanced the farm economy, little has been done to aid the small farmer who comprises the bulk of the population. Even today, his methods of cultivation are crude and his awareness of modern agricultural practices is slight. In addition, dependence on sugar still is potentially dangerous. Markets for this crop are not dependable and when world demands drop the economic structure of the nation is severely effected. Industrial development will continue only through a sensible utilization of the nationts natural resources. Although there are modest reserves of iron ore it does not seem sensible to plan construction of a steel mill. This has been proposed, however, and prior to this a shipyard and munitions factory were built. Projects such as these can undo the benefits of less grandiose but more rational programs that have been carried out in the past quarter century. One detriment to economic development that existed in the past, under-population; no longer is present. Since 1900 population has expanded 500 per cent and the country appears headed for densities that now beset many other West Indian islands. Over population is a major factor contributing to the many economic ills that plague these islands. In order to accommodate the increasing numbers of people and still provide a decent standard of living, the Dominican Republic must effectively utilize all available farmland, strengthen the position of the small fanner, and continue the expansion of light industries that are natural to the country.