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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modeling and Evaluating Lead-frame CSPs for Radio-Frequency Integrated Circuit Applications

Huang, Hui-Hsiang 30 June 2001 (has links)
­^¤åºK­n¡G In this thesis, a two-step de-embedded techniques was applied to measure the important parameters, ft and fmax , of the heterojunction bipolar transistors(HBTs). The same technique was also used to measure the wide-band S parameters for modeling and evaluating the bump chip carrier(BCC) packages. In the simulation, the Ansoft HFSS simulator was used to calculate the insertion and return losses for some bare and packaged test chips. Comparison between simulated and measured results has been discussed in detail to illustrate the applicability of the HFSS simulator.
2

An analysis of the significance of sub-regional partnerships in the community sport policy process

Harris, Spencer January 2014 (has links)
Community sport policy is characterised as complex and multi-faceted partly due to the number of agencies involved. This thesis explores the community sport policy process in England, specifically the significance of the relationship between CSPs and NGBs in the community sport policy process. The four key objectives of this study are (i) to analyse the significance of the relationship between CSPs and NGBs with regard to the national community sport policy process; (ii) to analyse the significance of the relationship between CSPs and NGBs in local-level policy making and policy implementation; (iii) to identify CSP and NGB attitudes and perceptions toward the community sport policy process; and as the study focuses on the meso-level of analysis, (iv) to evaluate the explanatory value of selected meso-level theories of the policy process in developing a better understanding of the community sport policy process. This study uses a mixed method comprising a questionnaire and semi-structured interviews. Initially, a quantitative questionnaire was used to gather information regarding CSPs and NGBs and support the selection of CSP cases. From this CSP-based case studies were developed involving semi-structured interviews with CSP, NGB and local authority representatives. The study draws attention to the hierarchical nature of the community sport policy process, the implications for collaboration, the mediating role of CSPs in national and local policy settings, and the associated challenges that agents face in implementing community sport policy. The study emphasises the value of theoretical pluralism in analysing the community sport field, particularly the combined used of meso-level frameworks such as the Advocacy Coalition Framework and the Policy Networks Approach with micro-level considerations from implementation theory and the partnership literature. It concludes that empirically, it is only by giving policy agents a voice that we can develop a more accurate understanding of the policy process and that practically only by harnessing the commitment and energy of the grassroots can we step toward a more effective policy community.
3

Robustness and stability in dynamic constraint satisfaction problems

Climent Aunés, Laura Isabel 07 January 2014 (has links)
Constraint programming is a paradigm wherein relations between variables are stated in the form of constraints. It is well-known that many real life problems can be modeled as Constraint Satisfaction Problems (CSPs). Much effort has been spent to increase the efficiency of algorithms for solving CSPs. However, many of these techniques assume that the set of variables, domains and constraints involved in the CSP are known and fixed when the problem is modeled. This is a strong limitation because many problems come from uncertain and dynamic environments, where both the original problem may evolve because of the environment, the user or other agents. In such situations, a solution that holds for the original problem can become invalid after changes. There are two main approaches for dealing with these situations: reactive and proactive approaches. Using reactive approaches entails re-solving the CSP after each solution loss, which is a time consuming. That is a clear disadvantage, especially when we deal with short-term changes, where solution loss is frequent. In addition, in many applications, such as on-line planning and scheduling, the delivery time of a new solution may be too long for actions to be taken on time, so a solution loss can produce several negative effects in the modeled problem. For a task assignment production system with several machines, it could cause the shutdown of the production system, the breakage of machines, the loss of the material/object in production, etc. In a transport timetabling problem, the solution loss, due to some disruption at a point, may produce a delay that propagates through the entire schedule. In addition, all the negative effects stated above will probably entail an economic loss. In this thesis we develop several proactive approaches. Proactive approaches use knowledge about possible future changes in order to avoid or minimize their effects. These approaches are applied before the changes occur. Thus, our approaches search for robust solutions, which have a high probability to remain valid after changes. Furthermore, some of our approaches also consider that the solutions can be easily adapted when they did not resist the changes in the original problem. Thus, these approaches search for stable solutions, which have an alternative solution that is similar to the previous one and therefore can be used in case of a value breakage. In this context, sometimes there exists knowledge about the uncertain and dynamic environment. However in many cases, this information is unknown or hard to obtain. For this reason, for the majority of our approaches (specifically 3 of the 4 developed approaches), the only assumptions made about changes are those inherent in the structure of problems with ordered domains. Given this framework and therefore the existence of a significant order over domain values, it is reasonable to assume that the original bounds of the solution space may undergo restrictive or relaxed modifications. Note that the possibility of solution loss only exists when changes over the original bounds of the solution space are restrictive. Therefore, the main objective for searching robust solutions in this framework is to find solutions located as far away as possible from the bounds of the solution space. In order to meet this criterion, we propose several approaches that can be divided in enumeration-based techniques and a search algorithm. / Climent Aunés, LI. (2013). Robustness and stability in dynamic constraint satisfaction problems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34785 / TESIS
4

Function and Evolution of Putative Odorant Carriers in the Honey Bee (Apis mellifera)

Foret, Sylvain, sylvain.foret@anu.edu.au January 2007 (has links)
The remarkable olfactory power of insect species is thought to be generated by a combinatorial action of G-protein-coupled olfactory receptors (ORs) and olfactory carriers. Two such carrier gene families are found in insects: the odorant binding proteins (OBPs) and the chemosensory proteins (CSPs). In olfactory sensilla, OBPs and CSPs are believed to deliver hydrophobic air-borne molecules to ORs, but their expression in non-olfactory tissues suggests that they also may function as general carriers in other developmental and physiological processes. ¶ Bioinformatics and experimental approaches were used to characterise the OBP and CSP gene families in a highly social insect, the western honey bee (Apis mellifera). Comparison with other insects reveals that the honey bee has the smallest set of these genes, consisting of only 21 OBPs and 6 CSPs. These numbers stand in stark contrast to the 66 OBPs and 7 CSPs in the mosquito Anopheles gambiae and the 46 OBPs and 20 CSPs in the beetle Tribolium castaneum. The genes belonging to both families are often organised in clusters, and evolve by lineage specic expansions. Positive selection has been found to play a role in generating a greater sequence diversication in the OBP family in contrast to the CSP gene family that is more conserved, especially in the binding pocket. Expression proling under a wide range of conditions shows that, in the honey, bee only a minority of these genes are antenna-specic. The remaining genes are expressed either ubiquitously, or are tightly regulated in specialized tissues or during development. These findings support the view that OBPs and CSPs are not restricted to olfaction, and are likely to be involved in broader physiological functions. ¶ Finally, the detailed expression study and the functional characterization of a member of the CSP family, uth (unable-to-hatch), is reported. This gene is expressed in a maternal-zygotic fashion, and is restricted to the egg and embryo. Blocking the zygotic expression of uth with double-stranded RNA causes abnormalities in all body parts where this gene is highly expressed. The treated embryos are `unable-to-hatch' and cannot progress to the larval stages. Our ndings reveal a novel, essential role for this gene family and suggest that uth is an ectodermal gene involved in embryonic cuticle formation.

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