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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.
31

Development of a pre-screening methodology to aid in determining potential energy savings in commercial buildings

Hicks, Dave C. 2008 December 1900 (has links)
This thesis presents a methodology developed to aid in the determination of potential sources and the potential scale of energy savings in commercial buildings. As a pre-screening tool, the methodology is designed to serve as the first analysis of the building’s potential for energy savings using limited data prior to a site visit. A Microsoft® Excel-based tool was developed to perform this analysis semi-automatically with user operation. A fundamental concept used in this methodology is that of the energy balance load, defined as heating plus electricity minus cooling. The methodology is designed to require only historical weather data, historical whole-building energy consumption data, the total conditioned floor area, and the basic function of the building. Upon following a short procedure developed and outlined in this thesis, this limited data yields information that can lead to conclusions about the building’s energy consumption. The output information includes estimates of a major building thermal parameter—the building’s overall heat transfer coefficient including the total outside air flow rate into the building. In addition to providing this information, the Excel tool includes already-formatted plots of the energy consumption commonly used in energy analysis. These include cooling, heating, and electricity vs. both outside air temperature and time. Three case studies illustrate the utility of this methodology. The calculated energy balance load—calculated using parameters determined through this methodology—yielded values on average within 5.4% of measured values.
32

The Pre-Classical Symphony: A Study of Terminology and Structure

Lin, Huey-Yea 24 June 2000 (has links)
­^¤å´£­n¡G The pre-classical era is the crucial stage for the development of the symphony. At this stage, the works are plentiful but with no explicit definition and forms. Also, with the various terminologies set by composers, it causes a chaotic situation at the early development of the symphony. Therefore, this thesis focuses on the issues of symphony development in the pre-classical era and the problems caused by the uncertain terminology. The thesis consists of four chapters. Chapter One is the discussion of the relevant contexts, including the background of that era, the social status of composers, the development of the orchestra, and the forming of the core of the symphony. At the very beginning, the thesis discusses the transition of the whole society at the early eighteenth-century. Many new concepts affected by the Enlightenment were being produced at that times especially in music and the composition was diversified. What should take into consideration is the social status of the composers at that times. It is because most of them were employed by the aristocrats or bourgeoisies; hence, these composers had produced plenty of works. This affected the organization of the orchestra and the five great symphonies development. Chapter Two defines the various terminologies prevalent at the time and clarifies their conceptual differences. The origin of the term "symphony" and the meaning it represents in the pre-classical era is first presented. Then, it discusses the various terminologies step by step. Chapter Three elaborates the content of the symphony. That is the manipulation of the orchestration and of the integral elements (including movements, musical forms, texture, and harmony). The discussion is made in two areas: these musical pieces entitled "symphony" and those "non-symphony". Chapter Four concludes the discussion of the effects of the pre-classical era as well as its subsequent influences. Music terminology is extremely important. Not only it represent what music but it also gives the audience the foremost impression as well. Unfortunately, due to the inconsistency of terminology and the unconformity of the orchestration rendered to the prototype symphonies, much misunderstanding resulted. Through the orchestration and the content of works, we perceived the works in pre-classical era would be titled with a variety of terminologies. Also, they made great contribution for the composition improvement and established a good foundation for the orchestra development.
33

Conceptual and procedural understanding of algebra concepts in the middle grades

Joffrion, Heather Kyle 25 April 2007 (has links)
In this study, the balance between conceptual and procedural teaching and its effect on the development of algebraic reasoning was examined. Participants included two seventh grade mathematics teachers and their students in targeted classes (N = 33). One video taped lesson from each teacher was selected for in-depth analysis of the balance between conceptual teaching, procedural teaching, and classroom time that included neither. Student participants took pretest and posttest algebra tests. Distribution of student responses and scores were analyzed for the degree of conceptual understanding demonstrated by students and then related to observed instructional practices. It was concluded that the students of the teacher with a more explicit conceptual emphasis in her lessons performed better on the test and were better able to exhibit flexible reasoning in unfamiliar contexts. Students whose teacher focused more heavily on procedural instruction without conceptual connections were less flexible in their reasoning and unable to apply some of the procedures taught in class.
34

Performance Evaluation of Data Access Latency Hiding Techniques in Processor Design

Jhang, Jia-hao 11 September 2007 (has links)
Due to the effect of deep submicron technology, the gap between processor speed and memory access performance increases continuingly. In order to improve performance degradation due to the performance gap, one way is to fetch the data about to be accessed by processor to buffer memory on the processor chip in advance. The memory access waiting time can thus reduced between main memory and cache memory on the processor. Previous research utilizes low-level techniques to pre-fetch data, such as insertion of pre-fetch instructions and pre-fetch with predicted data location based on dynamic learning. They do not utilize analysis on program¡¦s high-level data structure to assist data pre-fetch. In this research, we carried out performance evaluation on our proposed data pre-fetch technique based on analysis of high-level data structures. We also compare our method with some existing low-level data pre-fetch techniques. The evaluation metrics includes the accuracy of data pre-fetches, memory latency hiding, and overall execution performance.
35

The 1819 edition of the Hsin-an Hsien-chih: acritical examination with translation and notes: Hong Kong, Kowloonand the New Territories, 1644-1842

Ng, Yuk-lun, Peter., 吳毓璘. January 1961 (has links)
published_or_final_version / History / Master / Master of Arts
36

Integrated mining and preconcentration systems for nickel sulfide ores

Weatherwax, Trent 05 1900 (has links)
As part of a strategic research initiative at UBC to design and evaluate integrated underground mining and mineral processing systems, work has been done to determine how to utilize the coarse rejects of pre-concentration in the underground environment. An amenability study for nine orebodies from four of Xstrata Nickel’s Ontario operations evaluated both processing and waste disposal methods. Metallurgically the orebodies showed amenability to dense media separation and conductivity sorting. The dense media results showed high mass rejections and high metal recoveries for all nine orebodies. Conductivity sorter results were not as consistent, but still showed good results. Dense media rejects were examined to determine the applicability of their use in rockfills and composite minefills. The geotechnical properties indicated that the rejects would provide a competent material for minefills. The mix designs were examined for both strength and rheological properties and showed that fills utilizing rejects were comparable to fills currently used by industry. Composite fills containing rejects had significantly lower void ratios, decreasing cement requirements for a given strength requirement. Conceptual designs for pre-concentration systems based on the metallurgical, reject characterization, and mix design were developed for each of the four mines in the study. The designs took into consideration the current mining plans.
37

Influence préraphaélite sur les beaux-arts et la littérature d'expression française

Ozenne, Nadine Hélène January 1974 (has links)
No description available.
38

Behaviour of GFRP prestressed concrete straps

El-Sayed, Yasmine 30 September 2011 (has links)
Steel straps are being used for confinement purposes of steel-free bridge deck slab. The objective of this study was to use GFRP prestressed concrete straps as an alternative to steel straps, and assess the effect of the alkaline concrete environment on the long-term performance of GFRP. Each strap was 160 x100 mm2 in cross section, 2000 mm in length and pre-tensioned with two 16 mm diameter GFRP strands. The experimental study included testing three sets of concrete straps, pre-stressed at 35%, 45%, and 55% of ultimate strength of GFRP. The straps were tested in tension after being subjected to temperatures from -25oC to +40 oC in an environmental chamber. Another two sets of straps were cast and tested two and a half years later. The control and conditioned samples achieved comparable results proving that GFRP can withstand prestressing levels higher than 25% and up to 35% of their ultimate strength.
39

Digital pre-distortion of radio frequency digital to analog converters in a DOCSIS application

2014 October 1900 (has links)
The use of Community Antenna Television Network (CATV) cable systems are a very common way that subscribers use to access the internet and download data. The transmitters that send the signals to subscribers must conform to a very stringent specification known as DOCSIS. Using traditional high frequency design techniques to meet this specification often lead to a lengthy and difficult production process where several calibrations have to be made. In order to send a digitally modulated signal that conforms to the DOCSIS specification some sort of conversion between the discrete digital domain and the analog domain must occur. To accomplish this a Digital to Analog converter is used. In recent years, the clocking or sampling frequency that can be used for Digital to Analog converters (DACs) has been rapidly increasing. The clocking frequency is directly proportional to the bandwidth that can be transmitted. DAC's that have exceptionally high clocking frequencies can be referred to as Radio Frequency DAC's. The clocking frequency of these devices has now progressed to the point where direct digital synthesis can be used for a DOCSIS transmitter without any analog frequency conversion stages. Since Radio Frequency DAC's are real devices the output is not a perfect representation of the discrete signal that is sent to it. Unwanted distortion is added that can be measured at the analog output. Removal of this distortion or at least significantly reducing it could be the difference meeting or or not meeting the DOCSIS specification. This thesis will explore the usage of these devices in this application. The basic structure of DAC's as well as the distortion signals themselves will be investigated in order to develop a method where the distortion can be removed. Ideally this can be done in a way that is suitable to be integrated into a transmitter architecture and meet the specification. The frequency response of the major distortion products across the DOCSIS band is measured. Once this is done a way to match these frequency responses is needed so a cancellation signal can be created that removes the distortion. A method is developed that uses an iterative algorithm to find filter coefficients whose frequency response matches that of the distortion signals as closely as possible. Since these cancellation signals are added to the discrete signal to be transmitted before the interface with the Radio Frequency DAC the process is known as pre-distortion. The generated coefficients are used in digital filters as part of a pre-distortion design. Tests are performed with discrete signals that are close approximates to a DOCSIS signal that would be sent to a subscriber. Measured results show a decrease in the power of targeted distortion signals. The reduction of the distortion level is enough that the DOCSIS specification is met for all test signals.
40

Behaviour of GFRP prestressed concrete straps

El-Sayed, Yasmine 30 September 2011 (has links)
Steel straps are being used for confinement purposes of steel-free bridge deck slab. The objective of this study was to use GFRP prestressed concrete straps as an alternative to steel straps, and assess the effect of the alkaline concrete environment on the long-term performance of GFRP. Each strap was 160 x100 mm2 in cross section, 2000 mm in length and pre-tensioned with two 16 mm diameter GFRP strands. The experimental study included testing three sets of concrete straps, pre-stressed at 35%, 45%, and 55% of ultimate strength of GFRP. The straps were tested in tension after being subjected to temperatures from -25oC to +40 oC in an environmental chamber. Another two sets of straps were cast and tested two and a half years later. The control and conditioned samples achieved comparable results proving that GFRP can withstand prestressing levels higher than 25% and up to 35% of their ultimate strength.

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