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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.
271

Analyzing sustainable energy opportunities for a small scale off-grid facility: a case study at Experimental Lakes Area (ELA), Ontario

Duggirala, Bhanu 27 July 2010 (has links)
This thesis explored the opportunities to reduce energy demand and renewable energy feasibility at an off-grid science “community” called the Experimental Lakes Area (ELA) in Ontario. Being off-grid, ELA is completely dependent on diesel and propane fuel supply for all its electrical and heating needs, which makes ELA vulnerable to fluctuating fuel prices. As a result ELA emits a large amount of greenhouse gases (GHG) for its size. Energy efficiency and renewable energy technologies can reduce energy consumption and consequently energy cost, as well as GHG. Energy efficiency was very important to ELA due to the elevated fuel costs at this remote location. Minor upgrades to lighting, equipment and building envelope were able to reduce energy costs and reduce load. Efficient energy saving measures were recommended that save on operating and maintenance costs, namely, changing to LED lights, replacing old equipment like refrigerators and downsizing of ice makers. This resulted in a 4.8% load reduction and subsequently reduced the initial capital cost for biomass by $27,000, by $49,500 for wind power and by $136,500 for solar power. Many alternative energies show promise as potential energy sources to reduce the diesel and propane consumption at ELA including wind energy, solar heating and bio-mass. A biomass based CHP system using the existing diesel generators as back-up has the shortest pay back period of the technologies modeled. The biomass based CHP system has a pay back period of 4.1 years at $0.80 per liter of diesel, as diesel price approaches $ 2.00 per liter the pay back period reduces to 0.9 years, 50% the generation cost compared to present generation costs. Biomass has been successfully tried and tested in many off-grid communities particularly in a small-scale off-grid setting in North America and internationally. Also, the site specific solar and wind data show that ELA has potential to harvest renewable resources and produce heat and power at competitive rates compared to diesel and propane.
272

Predicting aircraft equipment removals during initial provisioning period

Fincke, Edwin August 09 1900 (has links)
An investigation was made into the characteristics of program elements and removals of Weapon Replaceable Assemblies aggregated at the system level for the purpose of developing a method to predict removals during initial provisioning periods. From examination of nine avionic systems over a 28 month period a binomial model was developed using a removal rate based on aircraft-months as a program element. The model is to be used before Fleet data are generated by obtaining aircraft-month estimates from the contractor and removal rate estimates from similar operational equipments. A probability distribution reflecting the degree of certainty is selected as a prior estimate. Then, as Fleet experience is accumulated the distribution is updated using Bayesian techniques and maturity growth curves. This distribution is used to give an estimate of current removal rate and to extrapolate to future removal rates.
273

Lay views of medicines and their influence on prescribing : a study in general practice

Britten, Nicola January 1996 (has links)
No description available.
274

Energy planning and energy policy analysis for Malaysia

Mohd Amin, Mohd Farid January 1996 (has links)
No description available.
275

Dynamic pricing under demand uncertainty in the presence of strategic consumers

Meng, Yinhan January 2011 (has links)
We study the effect of strategic consumer behavior on pricing, inventory decisions, and inventory release policies of a monopoly retailer selling a single product over two periods facing uncertain demand. We consider the following three-stage two-period dynamic pricing game. In the first stage the retailer sets his inventory level and inventory release policy; in the second stage the retailer faces uncertain demand that consists of both myopic and strategic consumers. The former type of consumers purchase the good if their valuations exceed the posted price, while the latter type of consumers consider future realizations of prices, and hence their future surplus, before deciding when to purchase the good; in the third stage, the retailer releases its remaining inventory according to the release policy chosen in the first stage. Game theory is employed to model strategic decisions in this setting. Each of the strategies available to the players in this setting (the consumers and the retailer) are solved backward to yield the subgame perfect Nash equilibrium, which allows us to derive the equilibrium pricing policies. This work provides three primary contributions to the fields of dynamic pricing and revenue management. First, if, in the third stage, inventory is released to clear the market, then the presence of strategic consumers may be beneficial for the retailer. Second, we find the optimal inventory release strategy when retailers have capacity limitation. Lastly, we numerically demonstrate the retailer's optimal decisions of both inventory level and the inventory release strategy. We find that market clearance mechanism and intermediate supply strategy may emerge as the retailers optimal choice.
276

On-Demand Energy Harvesting Techniques - A System Level Perspective

Ugwuogo, James January 2012 (has links)
In recent years, energy harvesting has been generating great interests among researchers, scientists and engineers alike. One of the major reasons for this increased interest sterns from the desire to have autonomous perpetual power supplies for remote monitoring sensor nodes utilizing some of the already available and otherwise wasted energy in the environment in a very innovative and useful way (and at the same time, maintaining a green environment). Scientists and engineers are constantly looking for ways of obtaining continuous and uninterrupted data from several points of interests especially remote or dangerous locations, using sensors coupled with RF transceivers, without the need of ever replacing or recharging the batteries that power these devices. This is now made possible through energy harvesting technologies which serve as suitable power supply substitutes, in many cases, for low power devices. With the proliferation of wireless energy in the environment through different radio frequency bands as well as natural sources like solar, wind and heat energy, it has become a desirable thing to take advantage of their availability by harvesting and converting them to useful electrical energy forms. The energy so harnessed or harvested could then be utilized in sensor nodes. Now, since these energy sources fluctuate from time to time, and from place to place, there is the need to have a form of energy accumulation, conversion, conditioning and storage. The stored energy would then be reconverted and used by the sensors nodes and/or RF transceivers when needed. The process through which this is done is referred to as energy management. In this research work, many types of energy harvesting transducers were explored including – solar, thermal, electromagnetic and piezo/vibration. A proof of concept approach for an on-demand electromagnetic power generator is then presented towards the end. While most, if not all, of the energy harvesting techniques discussed needed some time to accumulate enough charge to operate their respective systems, the on-demand energy harvester makes energy available as at and when needed. In summary, a system level design is presented with suggested future research works.
277

Passive solar options for reducing heating demand and maintain indoor climate in a multifamily house in Sweden

Joubert, Andras January 2014 (has links)
This research was carried out by studying possible renovation of a two-storey detached multifamily building by using passive solar design options in a cold climate in Borlänge, Sweden where the heating Degree Days are 4451 (base 20°C). Borlänge`s housing company, Tunabyggen, plans to renovate the project house located inthe multicultural district, Jakobsgårdarna. The goal of the thesis was to suggest a redesign of the current building, decrease the heating energy use, by applying passive solar design and control strategies, in a most reasonable way. In addition ensure a better thermal comfort for the tenants in the dwellings. Literatures have been studied, from which can be inferred that passive design should be abasic design consideration for all housing constructions, because it has advantages to ensure thermal comfort, and reduce the energy use. In addition further savings can be achieved applying different types of control strategies, from which the house will be more personalized, and better adapted to the user’s needs.The proposed method is based on simulations by using TRNSYS software. First a proper building model was set up, which represents the current state of the project building. Then the thermal insulation and the windows were upgraded, based on today's building regulations. The developments of the passive solar options were accomplished in two steps. First of all the relevant basic passive design elements were considered, then those advantages were compared to the advantages of applying new conventional thermostat, and shading control strategies.The results show that there is significant potential with the different types of passive solar design; their usage depends primarily on the location of the site as well as the orientation of the project building. Applying the control strategies, such as thermostat, and shading control, along the thermal insulation upgrade, may lead to significant energy savings (around 40 %), by comparison to the reference building without any upgrade.
278

Analysis Of Demand And Pricing Policies In Turkey Beer Market

Ozguven, Cemhan 01 August 2004 (has links) (PDF)
The purpose of this work is to study the beer market in Turkey in respect of demand analysis and with a view to assess whether the marketing and in particular pricing policies adopted by industry players in the period 1997-2002 have been efficient. Of specific interest is the near duopolistic structure of the market and the question whether pricing policies followed during the period 1997-2002 have been determinant in the observed sales volumes. The investigation focuses first on the analysis of the determinants of demand, and secondly on questioning whether pricing policies practiced in the market are optimal with respect to the objectives of the industry players. The major finding of the study is that beer prices in Turkey are below the optimal level, with respect to both revenue and profit maximizing objectives. Moreover, seasonality in beer demand can be exploited further with a high-low pricing scheme to improve the industry revenue.
279

Is Auckland ready for Chinese travellers?

Tian, Feng Sabrina January 2008 (has links)
The Chinese tourists market has become the 4th largest inbound market for New Zealand in 2007; it also ranks 6th in terms of expenditure. Chinese visitors spent a total of NZ $352 million to the year December 2006, an average of NZ $3,340 per person (Ministry of Tourism, 2006). The latest statistics released from New Zealand Tourism Research Council show that 122,045 Chinese visited New Zealand by the year ended January 2008. These crucial statistics – market size, length of stay and average spend – indicate the necessity for the New Zealand tourism industry to understand and provide for Chinese expectations and requirements. Auckland is New Zealand's key gateway, and it is vital that Auckland provides a first good impression for the rest of country. Chinese travellers visit New Zealand with great desire and expectations of experiencing an exotic land. They expect Auckland, as the biggest city in New Zealand, to provide them with a memorable city experience in a developed country. The purpose of this research is to study Chinese tourists' expectations and travel experiences, with a particular focus on investigating whether Auckland can provide suitable services and experiences which match their requirements and expectations. The research will build on the study by Bull (1991) and Ryan (1995), which looked at supply demand relationships and at the tourism industry attempts to balance the supply with the actual demands. It will also build on work by Zhao (2006) and Qu (2006) which explored the dimensions of Chinese demand and distribution channel factors at both origin and destination. The goal is to establish which factors are adequate or inadequate. A synthesis of the demand supply situation will enable the development of recommendations. It is envisage that these recommendations could be adopted by local government and the tourism industry, either as actions or as improvements to policy. With regards to the purpose of this research, a qualitative method was decided as the most relevant approach. Qualitative methods are useful for revealing and understanding what lies are behind any phenomenon about which little is known. Grounded theory is a qualitative research method that was developed for the purpose of studying a social phenomenon, and to generate a theory relating to a particular situation (Strauss & Corbin, 1994). The historical bases of the grounded theory approach matches the aim of this research, namely to reveal the relationships between tourists and the tourism industry and to gain a better understanding of Chinese tourists' expectation and satisfaction, and the level of the service which the Auckland tourism industry provides to Chinese travellers needs to match the Chinese market and requirements of travellers. The interviews were conducted with both Chinese travellers and the Auckland tourism industry, including hotel managers, restaurant managers, gift/souvenirs shop assistants, tour guides, and so on. The research shows Auckland is not ready for Chinese market yet. This result comes from three aspects: firstly, most Chinese tourists do not have clear requirements or expectations of Auckland before they come to New Zealand. This is mainly because of the limited promotional materials available in China about Auckland. Secondly, Chinese tourists do not have many opportunities to get to know Auckland's attractions and activities after they arrive in Auckland. Auckland city is New Zealand's most popular urban tourism destination in terms of population and gateway function provides tourism facilities and services to Chinese tourists. However, the findings highlighted most Chinese tourists found Auckland's tourism attractions to be unattractive to them due to the language barrier and itinerary issues. Thirdly, the research also found Chinese tourists have been driven away due to lack of hotel accommodations in Auckland, especially in the shoulder or high seasons. Auckland's accommodation facilities are facing a challenge. The increasing domestic and international visitors' numbers and insufficient hotel accommodations will be the major problem for Auckland for the next decade. Most of the Chinese tourists who were interviewed expressed their hope of knowing more about Auckland, however, these hopes will go unrealised until the city provides better attractions and more services for them.
280

Biological oxidations in oxic and anoxic marine environments, rates and processes.

Devol, Allan H. January 1975 (has links)
Thesis (Ph. D.)--University of Washington. / Bibliography: l. 156-177.

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