The Hydraulic Investigation of Perforated-Cylindrical-Intake Structure

ABSTRACT: Water surface level regulation and deviation of a constant value of discharge into the side channel, is the basis of the intake systems in irrigation channels, considering the main discharge rate fluctuates during the seasons. Hence, the necessity to design a structure which can control the consequences of discharge fluctuation in main channel and divert the constant value of demand water flow is more recognizable. The perforated-cylindrical-intake instrument is a new model of regulatorintake function, includes a free overflow on a cylindrical weir associated with intake element that can fulfil the main objective of a regulator and an intake devices, simultaneously. This research firstly, examined the different geometric conditions of the structure and determined the best one, then, tried to investigate the hydraulic function, operation method and the correlation of the intake discharge and upstream flow depth versus the discharge of the main channel in various condition of the structure based on an experimental work. The results show that in wide range of discharge variation in the main channel, the intake discharge variation were not considerable, also, it would be possible to measure and control the intake discharge precisely, installing a counter and a valve at the side channel

Multiple evolutionary origins of Trypanosoma evansi in Kenya

Trypanosoma evansi is the parasite causing surra, a form of trypanosomiasis in camels and other livestock, and a serious economic burden in Kenya and many other parts of the world. Trypanosoma evansi transmission can be sustained mechanically by tabanid and Stomoxys biting flies, whereas the closely related African trypanosomes T. brucei brucei and T. b. rhodesiense require cyclical development in tsetse flies (genus Glossina) for transmission. In this study, we investigated the evolutionary origins of T. evansi. We used 15 polymorphic microsatellites to quantify levels and patterns of genetic diversity among 41 T. evansi isolates and 66 isolates of T. b. brucei (n = 51) and T. b. rhodesiense (n = 15), including many from Kenya, a region where T. evansi may have evolved from T. brucei. We found that T. evansi strains belong to at least two distinct T. brucei genetic units and contain genetic diversity that is similar to that in T. brucei strains. Results indicated that the 41 T. evansi isolates originated from multiple T. brucei strains from different genetic backgrounds, implying independent origins of T. evansi from T. brucei strains. This surprising finding further suggested that the acquisition of the ability of T. evansi to be transmitted mechanically, and thus the ability to escape the obligate link with the African tsetse fly vector, has occurred repeatedly. These findings, if confirmed, have epidemiological implications, as T. brucei strains from different genetic backgrounds can become either causative agents of a dangerous, cosmopolitan livestock disease or of a lethal human disease, like for T. b. rhodesiense

A framework for the implementation of dynamic capabilities in successfully diversified conglomerates

Currently an overwhelming number of businesses have adopted diversification strategies and are exhibiting great success and have a prominent footprint on the global market. On the contrary, there is divergent scholarly thinking on the diversification-performance link and a wide-spread condemnation for the adoption of diversification strategies. As a result, managers of successful diversified companies are running far ahead their scholarly counterparts. Priori constructs, developed through an extensive and wide ranging literature review, focused the theory building power of the inductive case study research methodology employed. Through the lens of the emerging dynamic capabilities theory, four of the most highly successful diversified conglomerates over an extended period, were selected through the extreme case variant method, and were investigated in a longitudinal study from 1997 to 2013, to realise some of the key insights to their success. The outcomes of the research provided a rich explanation of how all five elements of dynamic capabilities are implemented in response to the increasingly dynamic environment within an entrepreneurial approach to sustain competitive advantage. The understanding of dynamic capabilities was extended through the emergence of two new themes, people and supportive structures. The findings gleaned are encapsulated within a simple framework that business practitioners can implement. In addition, the findings bring together a vast body of knowledge and provide a meaningful contribution in response to the lack empirical findings in business practice.Dissertation (MBA)--University of Pretoria, 2013.pagibs2014Gordon Institute of Business Science (GIBS)MBAUnrestricte

Pattern matching and refinement hybrid approach to circuit comparison

We present a new approach to circuit comparison which was developed to combine general applicability with most of the advantages of hierarchical processing. Two reasons often prevent hierarchical cell by cell comparison: hierarchical circuit extraction cannot be performed in all cases and if so, the resulting hierarchy is often non-isomorphic to the schematic hierarchy. Therefore, general applicability requires the ability to cope with flat circuits. Consequently, many tools compare flat netlists of transistors or logic gates. On the other hand, apart from the speed-up, hierarchical processing is superior in terms of error localization and functional but not topological isomorphism. Our objective was to develop a tool which exploits the latter two advantages of hierarchical processing, while not sacrificing general applicability. The basic principle of operation is the pattern matching of arbitrary subcircuits in larger circuits