Light emitting diode (LED) will have development in liquid crystal display (LCD) backlight. Nevertheless, the point source of LED is not suitable for large size panel. Therefore, this research will change the package which is bullet type and design gapless dual-curvature micro lens (GDML). Using the optics software TracePro is simulation luminance to compare of hexagon, triangular and dual-curvature micro lens, and fabrication of the better size. We can get metal model using micro-electro-mechanical systems (MEMS) technology after electroforming and hot embossing. The micro lens is formed by UV cure in metal model. It has different curvature and fill factor 100%. The advantage of electroforming is can manufacture a lot of product fast with high performance. The shrinkage rate is less than 0.5%. The collocation package of micro lens and LED chip can improve intensity and uniformity.

Semiconductor technology has already got into nanometer scale. As the dimension keeping scaling down, we can get more transistor in the same area, and furthermore the frequency and performance are also enhanced. But nowadays the development of the lithography technology has come to the neck, we must find another way to improve the performance of transistor. The reliability is more important in the shorter and shorter device channel. In this study, we fully discuss the electrical characteristics of the hot carrier effect at various temperature of 65nm MOSFETs under external mechanical stress. In order to strain the channel, silicon substrate is bent by applying external mechanical stress, the lattice of channel will be strained after applying uniaxial tensile stress. Therefore, we successfully improve drain current and carrier mobility of NMOS, but the hot carrier effect is more serious. In addition, we can understand the influence of hot carrier effect on strain silicon by bending silicon substrate with external mechanical stress. With the increase of curvature, substrate current goes up. We offer an explanation to verify this result. The temperature effect is also measured. The drain current and mobility increased with the temperature decreasing, but the substrate current increased with temperature increasing.

Generating enough heat to convert water into steam is a major expense for projects that inject steam into reservoirs to enhance hydrocarbon recovery. If the temperature of the injected fluid is lowered this expense would be reduced. In the past, attempts have been made to inject hot water instead of steam. The results have all been rather poor, the major problem being low sweep efficiency. The hot water just doesn’t enhance oil recovery enough. Adding propane to the steam injected in the reservoir lowers the boiling point of the light to intermediate hydrocarbon fractions, upgrading the oil and reducing viscosity. The goal of this investigation is to see if the same effects could be achieved when adding propane to hot water – making it a lower cost option for an injection operation. Results conclude that you need steam to achieve satisfactory recovery. These results reflect differences in heat injected by steam compared to that of hot water. Steam has a more penetrating effect, shooting into the reservoir where the hot water moves more slowly forward. The propane just doesn’t seem to have the same accelerating effect when used with water as it does when used with steam.

In this dissertation work, a constant temperature embossing process was developed and investigated. By softening and crystallizing a supercooled polymer at the same temperature, the embossing and solidification stages can be carried out isothermally without thermal cycling. The new process was demonstrated for replicating rectangular trenches with different aspect ratio for two different polymers PET and PEEK. The raw materials were characterized for their thermal and rheological properties to determine the processing parameters. The polymers were also characterized by a modified tensile testing apparatus to determine the tensile properties of the film during embossing. The processing parameters including embossing temperature, embossing pressure and embossing time were varied based on the material properties and optimized. A semi-empirical model was established to correlate the crystallizing kinetics of the materials to the change in rheological properties during embossing. The model was used as a tool to predict the rheological properties of the polymer at conditions where experimental determination is difficult. Finally, embossing simulations with the semi-empirical rheological model were conducted to study the unique process dynamics of constant-temperature embossing and verify some experimental findings. Different cases of constant-temperature embossing involving low to high rates of crystallization were simulated and compared with the conventional embossing process. Based on the experimental and simulation results, processing strategies for constant-temperature embossing were devised.

Thesis--M. Phil., University of Hong Kong, 1980.

The hydro-mechanical effects of high pressure fluid injections into jointed rock are considered mostly in the context of Hot Dry Rock (HDR) geothermal energy systems. In Part I, the mai n aspects ari sing from the HDR research at the "Camborne School of Mines (CSM) and Los Alamos Nat iana 1 Laboratory (LANL) projects are reviewed. Previous approaches to fluid-rock interacti ons at these projects and important observed phenomena are highlighted. Fundamental aspects of rock joint geometry, mechanical behaviour and flow regimes within jointed rock are also reviewed. These aspects are then related to possible conditions in HDR systems. The role of in situ stress conditions is of great significance in this study and is reviewed theoretically and in detail for both the CSM and LANL project sites. The revi ew incl udes a comprehensi ve seri es of measurements, by different techniques, organised and interpreted by the author at the CSM project. In Part II, model development, the emphasis is on intermediate fluid pressures which are too high for simple diffusion alone and too low for tensile hydraulic fracturing. The dominant mechanical activity is one of joint shear. Strike-slip shearing due to fluid injection is examined in two dimensions with the numerical model FRIP, which has been extended by the author. Similar behaviour is examined in three dimensions with an analytical model which is linked to microseismic observations. This model explains the observed phenomenon of downward shear growth. Joint distribution and mechanical properties, and their effect on fluid diffusivity, are examined and used in analytical models of fluid pressure pulse propagation, tracer transport, and rock stress increment transfer. All models are used to help interpret field data, mainly from the CSM project. The models are also of potential application to hydrocarbon reservoir stimulation, liquid waste disposal and leakage from high pressure water tunnels.

published_or_final_version / Mechanical Engineering / Master / Master of Philosophy

No description available.

Oron för att utsättas för hot eller våld är för många anställda inom vårdsektorn en daglig psykisk påfrestning. Studiens syfte var att beskriva sjuksköterskans upplevelser i samband, med hot och våld i den somatiska vården samt hur det hanteras. Studien är en litteraturstudie baserad på vetenskapliga artiklar. I databaserna Medline och Cinahl fann författarna 33 artiklar varav 7 artiklar ansågs svara mot studiens syfte, genom manuell sökning valdes 5 artiklar ut. De vetenskapliga artiklarna granskades och bedömdes vad gällde vetenskaplig kvalitet. Vid analys av artiklarnas resultat framkom tre tema i form av 1.Upplevelser vid hot och våld, 2. Hantering av upplevelser som uppstår vid hot och våld, 3. Upplevelser av brist av stöd från arbetsledningen samt underrapportering av våldsincidenter. Ilska, rädsla, stress, maktlöshet och hjälplöshet var de mest omskrivna upplevelserna. De viktigaste faktorerna i hanteringen av upplevelser var support från kollegor samt coping strategier. Det framkommer också hur personalen upplever avsaknad av stöd från arbetsledningen vid hot och våld incidenter, samt vikten av rapportering av dessa incidenter. När sjuksköterskan har kunskap om olika upplevelser som kan uppstå samt hantera dessa på ett optimalt sätt, medför det att sjuksköterskan blir tryggare i sin yrkesroll. Detta genererar i att de omvårdnadsåtgärder som patienten skall ha genomförs.

Solar Domestic Hot Water systems and air-source heat pumps offer the potential for energy savings in residential hot water production, however their performance is limited in cold climates, where the low ambient temperature reduces the collector efficiency or the heat pump coefficient of performance. Combining these systems into a Solar-Assisted Heat Pump can alleviate these limitations by reducing the required collector temperature and by providing an increased heat pump evaporator temperature. This study is a continuation of the development of an Indirect Solar-Assisted Heat Pump undertaken at the Queen’s University Solar Calorimetry Laboratory. Previously, a numerical study compared its performance to existing technology, and based upon this feasibility analysis, a prototype was constructed for controlled laboratory tests using simulated solar input. In the current study, the prototype was modified to include a novel hybrid collector such that its performance under actual weather conditions throughout the year could be assessed. On sunny days, the system experienced daily averaged collector efficiencies between 0.47 and 0.88, depending on the flow rate and season. Averaged heat pump coefficients of performance of 2.54 to 3.13 were observed. Overcast days experienced reduced coefficients of performance, between 2.24 and 2.44. However, on overcast days, upwards of 76% of the collected energy gain was from convection with the surroundings. Based upon these experimental results, a model for the hybrid collector was developed. Annual simulations of the system were conducted to compare the performance of the solar heat pump system when fitted with the hybrid collector relative to cases with more conventional glazed and unglazed collectors commonly used in solar thermal systems. Results were produced for three Canadian cities: Toronto, Vancouver and Winnipeg. The heat pump with the hybrid collector outperformed the other collectors in the Toronto climate, with a free energy ratio of 0.548. Adding a thermally controlled valve to the hybrid collector was proposed to further increase the annual free energy ratio, and was shown to perform best in all three cities, with free energy ratios of 0.558, 0.576 and 0.559 for Toronto, Vancouver and Winnipeg, respectively. It is proposed that additional improvements could be achieved by allowing the collectors to deliver heat directly to the storage tank, by circumventing the heat pump if the conditions were favorable. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2012-01-06 13:44:41.77