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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.
151

A framework for knowledge discovery within business intelligence for decision support

Basra, Rajveer Singh January 2008 (has links)
Business Intelligence (BI) techniques provide the potential to not only efficiently manage but further analyse and apply the collected information in an effective manner. Benefiting from research both within industry and academia, BI provides functionality for accessing, cleansing, transforming, analysing and reporting organisational datasets. This provides further opportunities for the data to be explored and assist organisations in the discovery of correlations, trends and patterns that exist hidden within the data. This hidden information can be employed to provide an insight into opportunities to make an organisation more competitive by allowing manager to make more informed decisions and as a result, corporate resources optimally utilised. This potential insight provides organisations with an unrivalled opportunity to remain abreast of market trends. Consequently, BI techniques provide significant opportunity for integration with Decision Support Systems (DSS). The gap which was identified within the current body of knowledge and motivated this research, revealed that currently no suitable framework for BI, which can be applied at a meta-level and is therefore tool, technology and domain independent, currently exists. To address the identified gap this study proposes a meta-level framework: - ‘KDDS-BI’, which can be applied at an abstract level and therefore structure a BI investigation, irrespective of the end user. KDDS-BI not only facilitates the selection of suitable techniques for BI investigations, reducing the reliance upon ad-hoc investigative approaches which rely upon ‘trial and error’, yet further integrates Knowledge Management (KM) principles to ensure the retention and transfer of knowledge due to a structured approach to provide DSS that are based upon the principles of BI. In order to evaluate and validate the framework, KDDS-BI has been investigated through three distinct case studies. First KDDS-BI facilitates the integration of BI within ‘Direct Marketing’ to provide innovative solutions for analysis based upon the most suitable BI technique. Secondly, KDDS-BI is investigated within sales promotion, to facilitate the selection of tools and techniques for more focused in store marketing campaigns and increase revenue through the discovery of hidden data, and finally, operations management is analysed within a highly dynamic and unstructured environment of the London Underground Ltd. network through unique a BI solution to organise and manage resources, thereby increasing the efficiency of business processes. The three case studies provide insight into not only how KDDS-BI provides structure to the integration of BI within business process, but additionally the opportunity to analyse the performance of KDDS-BI within three independent environments for distinct purposes provided structure through KDDS-BI thereby validating and corroborating the proposed framework and adding value to business processes.
152

A cellular automata approach for the simulation and development of advanced phase change memory devices

Vázquez Diosdado, Jorge Alberto January 2012 (has links)
Phase change devices in both optical and electrical formats have been subject of intense research since their discovery by Ovshinsky in the early 1960’s. They have revolutionized the technology of optical data storage and have very recently been adopted for non-volatile semiconductor memories. Their great success relies on their remarkable properties enabling high-speed, low power consumption and stable retention. Nevertheless, their full potential is still yet to be realized. Operations in electrical phase change devices rely on the large resistivity contrast between the crystalline (low resistance) and amorphous (high resistance) structures. The underlying mechanisms of phase transformations and the relation between structural and electrical properties in phase change materials are quite complex and need to be understood more deeply. For this purpose, we compare different approaches to mathematical modelling that have been suggested to realistically simulate the crystallization and amorphization of phase change materials. In this thesis the recently introduced Gillespie Cellular Automata (GCA) approach is used to obtain direct simulation of the structural phases and the electrical states of phase change materials and devices. The GCA approach is a powerful technique to understand the nanostructure evolution during the crystallization (SET) and amorphization (RESET) processes in phase change devices over very wide length scales. Using this approach, a detailed study of the electrical properties and nanostructure dynamics during SET and RESET processes in a PCRAM cell is presented. Besides the possibility of binary storage in phase change memory devices, there is a wider and far-reaching potential for using them as the basis for new forms of arithmetic and cognitive computing. The origin of such potential lies in a previously under-explored property, namely accumulation which has the potential to implement basic arithmetic computations. We exploit and explore this accumulative property in films and devices. Furthermore, we also show that the same accumulation property can be used to mimic a simple integrate and fire neuron. Thus by combining both a phase change cell operating in the accumulative regime for the neural body and a phase change cell in the multilevel regime for the synaptic weighting an artificial neuromorphic system can be obtained. This may open a new route for the realization of phase change based cognitive computers. This thesis also examines the relaxation oscillations observed under suitable bias conditions in phase change devices. The results presented are performed through a circuit analysis in addition with a generation and recombination mechanism driven by the electric field and carrier densities. To correctly model the oscillations we show that it is necessary to include a parasitic inductance. Related to the electrical states of phase change materials and devices is the threshold switching of the amorphous phase at high electric fields and recent work has suggested that such threshold switching is the result of field-induced nucleation. An electric field induced nucleation mechanism is incorporated into the GCA approach by adding electric field dependence to the free energy of the system. Using results for a continuous phase change thin films and PCRAM devices we show that a purely electronic explanation of threshold switching, rather than field-induced nucleation, provides threshold fields closer to experimentally measured values.
153

The use of focus groups to develop the Advanced Patient Care course at The University of Arizona College of Pharmacy

Bono, Corey, Geier, Carey, Gimness, Anna January 2010 (has links)
Class of 2010 Abstract / OBJECTIVES: To determine what information and clinical skill sets current student pharmacists, recent graduates, and current preceptors felt should be incorporated in designing the Advanced Patient Care course at The University of Arizona College of Pharmacy (UACOP). METHODS: This was a prospective, descriptive study using focus groups. Subjects included students in the fourth year of a four-year Doctor of Pharmacy program at the UACOP currently on rotations, recent UACOP graduates practicing in residency programs, and current preceptors for the UACOP who work closely with the students. Participants verbally consented and completed a demographic questionnaire. The three focus group sessions (each lasting 1.5 hours) were audiotaped, and the data was coded into categories and subcategories based on frequencies of topics that were discussed. RESULTS: A total of 14 subjects, separated into three focus groups of students, residents, and preceptors were held with 5, 4, and 5 subjects respectively. Both men and women were included in the study, with only females in the resident group. The student, resident, and preceptor groups had mean ages of 29±5.4, 28±3.7, and 47±12 years respectively. Overall the most commonly discussed topics included various learning techniques, specific drug or disease state focuses, and the importance of professionalism. CONCLUSIONS: Many insightful ideas for the Advanced Patient Care course soon to be implemented at the UACOP were generated by the three focus groups. Focus groups including pharmacy students, residents and preceptors are a useful tool for designing new courses and determining information and skill sets to be added to college of pharmacy curriculums.
154

THE EFFECT OF THE ADVANCED PLACEMENT TRAINING AND INCENTIVE PROGRAM ON INCREASING ENROLLMENT AND PERFORMANCE ON ADVANCED PLACEMENT SCIENCE EXAMS

Ramsey, Susan 27 April 2012 (has links)
The purpose of this study is to examine the effectiveness of the National Math and Science Initiative’s Advanced Placement Training and Incentive Program (APTIP) on the number of students taking AP science courses and their performance. The study evaluated 39 schools over a six-year period in six states that participate in the APTIP. The National Math and Science Initiative provided data for cohort I. A general linear model for repeated measures was used to evaluate the data. Data was evaluated three years prior to the intervention and three years during the intervention, which will actually continue for two more years (2012 and 2013) since cohort I schools were awarded five years of support. Students in APTIP schools enrolled in more AP science exams (AP Biology, AP Chemistry, AP Environmental Science, and AP Physics-B) over the course of the intervention. The quantity of students earning qualifying scores increased during the intervention years. APTIP is a multi-tiered program that includes seven days of teacher training, three six-hour student prep sessions, school equipment, reduced exam fees, and monetary incentives for students and teachers. This program positively impacted the quantity of enrollment and qualifying scores during the three years evaluated in this study. Increases in the number of female and African American students’ test takers their and qualifying scores were seen in all three years of the APTIP intervention. This study supports the premise that the first step to increasing the Science, technology, engineering, and math (STEM) pipeline is giving access to advanced courses to more students in high schools
155

Sonochemical Defluorination of Perfluorinated Compounds by Activated Persulfate Ions

Gray, Kevin M 06 July 2018 (has links)
Polyfluorinated compounds (PFCs) are a class of anthropogenic chemicals that have been found in groundwater and wastewater around the world. Perfluoroctane sulfonate (PFOS) and perfluoroctanoic acid (PFOA) are primarily used for industrial surfactants, and aqueous film forming foams (AFFFs). These PFCs and many of their constituents have been found to be carcinogenic to humans and other animals. A simple method for defluorination of these compounds is needed. Advanced oxidation of PFOS, PFHxS, and PFBS-k was carried out using activated sodium persulfate through ultrasonic irradiation with the following condition; [PFC] = 20 millimolar (mM), [Na2S2O8] = 25 mM, pH = 7, and 25°C. Fluoride concentrations were quantified by ion chromatography (IC). In laboratory experiments, batch reactions of PFBS solutions were conducted in purified water at different pH conditions and N2S¬2O8: PFBS molar ratios of 1:1, 2:1, 10:1, and 100:1 respectively. Solution pH was maintained at 7 using HNO3. Of the three compounds, PFHxS had the greatest defluorination (11%) after 120 minutes reaction time. However, PFBS-K had the greatest increase in defluorination (115%) between the control ultrasound (US) experiment and the combination experiment. When Na2S2O8 was increased, the defluorination ratio of PFBS decreased. This decrease was partly attributed to scavenging reactions between SO4¯• and S2O8²¯. These results show a synergism between ultrasonic irradiation and activated sodium persulfate as a form of advanced oxidation. Recommendations for further research into defluorination of PFOS and its constituents by ultrasonic degradation include: the use of high performance liquid chromatograph with accompanying mass spectrometry (HPLC/MS), the use of an ultrasonic probe with alternate frequencies, and the effects of surface tension on defluorination.
156

Tratamento de águas subterrâneas contaminadas com BTEX utilizando processo oxidativo de Fenton / Treatment of groundwater contaminated with BTEX using the Fenton oxidative process

Marchetti, Maykel Douglas 18 December 2009 (has links)
Há décadas enfrentamos as conseqüências causadas por atitudes poluidoras. Contudo, atualmente a preocupação ambiental aumentou devido aos efeitos potencialmente nocivos sobre a saúde humana, economia e meio ambiente.A contaminação do solo e das águas subterrâneas por compostos orgânicos voláteis é um problema que está se espalhando com rapidez, e uma das principais fontes poluidoras é o vazamento de tanques de armazenamento de combustível em auto-postos. A problemática desta contaminação é agravada tendo em vista que compostos tóxicos de solubilidade considerável em água, tais como BTEX, estão presentes nessa contaminação.Atualmente são utilizados métodos de tratamento, tais como a aeração, que apenas acabam transferindo os compostos orgânicos tóxicos da água para a atmosfera. O Processo Oxidativo Avançado de Fenton mostra-se promissor no tratamento de tais contaminações.Nossos objetivos foram testar o processo oxidativo e melhorar suas condições de aplicação, bem como projetar um equipamento capaz de realizar o processo de maneira automática.No presente trabalho, o POA mencionado mostrou-se eficiente e capaz de mineralizar os poluentes, reduzindo a poluição a níveis satisfatórios. As caracterizações foram feitas através de cromatografia gasosa, análise de metais através de espectroscopia de emissão por plasma e análise do carbono orgânico total. / From decades, the consequences caused by laid-back attitude towards environment are confronting people. However, currently, the environmental concerned was raised because of the potentially harmful effects on human health, economy and on the environment itself.The problem of soil and subterranean water contamination by volatile organic compounds is rapid spreading; being on of the main pollutant fount the leak of the fuel housing on the gas stations. This problem aggravates once toxic compounds which have considerable solubility on water, such as BTEX, are on this contamination.Currently, treatment methods are employed, such as aeration, which only transfers the toxic organic compounds from water to atmosphere. The Fenton advanced oxidative process manifests as a promising treatment of these contaminations.Our purpose was to test the oxidative process and improve the applicability conditions as well as project equipment able to accomplish the process on an automatic way.On this work the POA manifests efficient and able to mineralize the pollutants, decreasing the pollution to a satisfactory level. The characterization were made through gas chromatographic, the metal analyses were made by plasma emission spectroscopy and analysis of total organic carbon.
157

Genetic analysis of the effect of circadian clock genes on yield component traits in wheat

Wittern, Lukas Maximilian January 2018 (has links)
No description available.
158

TCE Removal Utilizing Coupled Zeolite Sorption and Advanced Oxidation

Hawley, Harmonie A 28 April 2003 (has links)
Trichloroethylene (TCE) is one of the most common groundwater pollutants in the United States. The EPA estimated that between 9% and 34% of the drinking water sources in the United States may contain TCE. The United States Environmental Protection Agency set a maximum contaminant level at 5 µg/L of trichloroethylene for drinking water. This study investigated the feasibility of removing TCE from water by sorption to ZSM-5 and advanced oxidation to destroy the TCE on the zeolite. Aqueous oxidation of TCE with Fenton's reagent was shown to be efficient for the destruction of TCE. The quantified by-products were cis-DCE and trans-DCE. ZSM-5 rapidly removed TCE from water. A Freundlich isotherm was created for the uptake of TCE by ZSM-5. Once TCE was sorbed to ZSM-5, preliminary experiments showed that the oxidation was able to destroy the TCE while producing the same by-products.
159

Modelling bidirectional radiance measurements collected by the advanced solid-state array spectroradiometer over Oregon transect conifer forests

Abuelgasim, Abdelgadir A. M. January 1986 (has links)
Thesis (M.A.)--Boston University / The primary objective of this research is to test and validate a geometric-optical bidirectional reflectance canopy model developed by Li and Strahler, with respect to actual forest canopy reflectance measurments. This model treats forest canopies as scenes of discrete, three dimensional objects that are illuminated and viewed from different positions in the hemisphere. The shapes of the objects, their count densities and patterns of placement are the driving variables, and they condition the mixture of sunlit and shaded objects and background that is observed from a particular viewing direction, given a direction of illumination. This mixture, in turn, controls the brightness apparent to an observer or a radiometric instrument. The Advanced Solid-State Array Spectroradiometer (ASAS) is chosen to be the sensor having the ability of collecting measurements at various look angles and its imaged reflectance was used to validate the model. The modelled BRF's were compared to actual ASAS measured BRF's in sites with different canopy structures and densities. The comparision revealed execellent match between the modelled and measured reflectance, and great ability of the model in predicting the shape and magnitude of the BRDF, in almost all the sites investigated. It is concluded that the geometric optics approach provided a good way to model the bidirectional reflectance distribution function of natural vegetation canopies, that captures the most important features exhibited by bidirectional measurements of such canopies. Further modifications have been suggested that will improve the predicted BRF's, and yield better results. [TRUNCATED]
160

Theory, modelling, and applications of advanced electromagnetic materials

Naeem, Majid January 2017 (has links)
A multitude of recent work predicts many novel concepts based on the availability of non-natural materials; some prominent examples include transformation optics (TO) and perfect lens. The interest in this eld has grown dramatically due to spec- ulated possibility to allow for continuously varying material properties to steer the incident wave at will, such as for the TO. The posed challenges for their realisation include the limitations of numerical modelling and manufacturing techniques. A de- sign scheme has been proposed, in this thesis, for composite materials: the desired electromagnetic properties of composites can be engineered by judiciously varying the volume fraction of the inclusion-to-host materials, by manipulating the geomet- ric arrangement of inclusions, or by altering their dielectric contrast. The analysis of the homogenised response of the designed materials at macro-scale requires effective medium modelling techniques. The existing effective medium approximation tech- niques have been discussed, and their pros and cons outlined. A homogenization scheme has been introduced that is based on the interaction of the incident wave and the nanoparticles at the micro-scale, which further requires efficient electromagnetic modelling. The conventional nanoparticle modelling techniques, as well as the state of the art, have been reviewed and a dipole-moment-based method to efficiently solve modern nanoparticle-based electromagnetic problems has been outlined. The appli- cability of the proposed scheme has been demonstrated by employing it to design various EM devices. An improved permittivity extraction scheme has been proposed for the homogenization of composites. Unlike classical homogenization schemes, the extracted parameters, using the proposed technique, follow the relation between the real and imaginary parts, that is, Kramers-Kronig relations. Several random and periodic structures have been simulated for the purpose of extracting the ef- fective electromagnetic properties and interpreting the results so as to establish a connection between them.

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