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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.
261

Developing capacity for agricultural water management: Current practice and future directions

Franks, Tom R., Garces-Restrepo, C., Putuhena, F. January 2008 (has links)
Yes / This paper defines concepts of capacity and capacity development for agricultural water management, and particularly the contributions made by ICID in this area in the recent past. Working from a theoretical framework of overlapping domains of capacity development ¿ the enabling environment, the organisational and the individual domains, with knowledge management as a cross-cutting theme ¿ the paper reviews previous work in the field and then summarises a range of case studies from the sector which illuminate key aspects of these different domains. The paper notes the need to accommodate a rapidly-changing context for agricultural water management to take account of the increasing demand for water resources in all sectors, and the consequent requirement for support of new approaches to capacity development. These new approaches emphasise the growing importance of authentic knowledge, internally-generated learning and self-development, whether at the level of the organisation or the individual. The paper also recognises the need for continuing and long-term support of capacity development, particularly in processes of organisational and institutional change, where there is no single set of guidelines or practices which will fit every situation. Specific directions for future work are suggested, including increased attention to monitoring and evaluation of capacity development, and closer links to emerging work on water governance. / None
262

Scaling Up Mental Health Services in Zambia: Challenges and Opportunities Reported in an Education Project.

Karban, Kate, Bowa, A.C., Patrick, S., Penson, B., Walker, B., Ng'andu, R., Mbewe, E. January 2013 (has links)
yes / The need to increase the capacity of developing countries to meet the mental health needs of their populations is widely acknowledged. This article examines some of the challenges associated with a British Council DelPHE project aimed at strengthening the capacity of mental health educators to prepare the mental health workforce in Zambia for a shift from an institutional to a community-based model of care. The analysis draws on data from two focus groups in which the participants were drawn from college educators who had taken part in workshops intended to enhance curriculum alignment to ensure that the education and training provided for clinical officers (psychiatry) and mental health nurses was "fit for purpose." In particular, the article highlights their perspectives on some of the tensions in focusing on mental health as opposed to broader health care and in ensuring appropriate opportunities for practice or field placements. The continuing impact of stigma and limited resources available for mental ill-health is acknowledged within the wider context of inequities in mental health care. Findings of this evaluation may be applicable to other sub-Saharan contexts, but should be understood only within the Zambian context.
263

The Local Composite Index: A Critical Analysis

Driscoll, Lisa G. 11 December 1998 (has links)
The purpose of this study was to develop an explanation for the volatile behavior of the Local Composite Index, Virginia's measure of public school division fiscal capacity. This study documented and analyzed the behavior of the mathematical and structural components of the current formula over the period inclusive of Biennia 1984-86 through 1996-98. It was implemented in five phases: 1. Literature Review. Literature related to public school division fiscal capacity was reviewed: a) To identify normative and procedural concepts important to the philosophical development of fiscal capacity. b) To delineate the various models used across the United States in the determination of public school fiscal capacity. c) To examine components of indices, their application, and criteria for evaluating their behavior. 2. Local Composite Index Review. Information was collected from various sources regarding the Local Composite Index and its components for all school divisions in the Commonwealth. 3. Database Development. A relational database was developed to facilitate exploratory trend analyses of the LCI and its components. 4. Analysis. An identification and analysis of three trends was selected, defined, and undertaken: a) Biennial Change Rate of the Indicators, Local and State b) Biennial Change Rate of the Standardized Indicators, Local and State c) Net Biennial Change Rate of the Local to State Ratio for the Standardized Indicators 5. Case Studies. Five case studies of public school divisions and the Commonwealth of Virginia were performed to provide an in-depth and quantitative analysis of the interaction of the various component trends of the Local Composite Index and their resultant effects. The study identified specific phenomena and their percentage contribution to the volatility of the Local Composite Index. The study found three interactive effects of the LCI ratio structure that contribute to its volatility: * The Ratio structure can enhance the LCI value. * The Ratio structure can dampen the LCI value. * The ratio structure allows for Synthetic Change within the Local or State Standardized Indicators, which stimulates unpredictable patterns of volatility. / Ph. D.
264

Language and Working Memory Capacity in Early Adulthood: Contributions From First and Second Language Proficiency

Zaki, Hossam M. 06 June 2005 (has links)
The aim of this project was to investigate the impact of language proficiency (represented in first and second language) on working memory capacity. A sample of 100 college students from Virginia Tech University completed an on-line survey, performed 2 computer-based working memory capacity tasks (the OSPAN and the Letter Rotation) and had their first language (L1) as well as their second language (L2) proficiency tested. All participants were classified on a five-point likert scale from "poor" to "excellent". Verbal WMC (as measured by OSPAN) was associated with L2 proficiency. However, the L2 "excellent" group did not differ in their OSPAN from the remaining four groups of L2 proficiency classification. No correlation was found between the two WMC tasks. / Ph. D.
265

Influence of the Number of Degrees of Freedom on the Capacity of Incoherent Optical Fiber Communication Systems

Teotia, Seemant 15 June 2006 (has links)
The purpose of this dissertation is to find the channel capacity in optical fiber communication systems when incoherent detection is used with single (polarization filtering) and two-polarizations (no polarization filtering). Optical fiber systems employ photodetectors that convert optical intensity to electrical current. Bandpass vector fields may be represented by four orthogonal baseband components corresponding to two quadrature phases and two orthogonal polarizations. Intensity is proportional to the sum of the squares of these four components. In the case of a coherent receiver, a strong optical local oscillator (in phase and with same polarization as the signal) is added to the signal prior to the photodetector. This results in the removal of the quadrature phase and polarization components, and reduces to the one degree of freedom (DOF) case of signal plus local oscillator shot noise for which the Shannon channel capacity formula applies. Electrical noise following the photodetector may also be neglected if there is an optical amplifier before the photodetector in the receiver. The amplifier introduces amplified spontaneous emission noise containing both quadrature phase components and both polarizations (4 DOFs), but the 2 DOF case would result if a polarization filter were used. Although the 1 and 2 DOF cases are of less practical interest than the 4 DOF case, they provide useful benchmarks for comparing performance limits. We evaluate both spectral efficiency limits (bps/Hz) in the limit of high and low SNR for the 1,2 and 4 DOF cases and also find the power efficiency (minimum number of photons per bit) for each of these cases. It is shown that for high SNR the spectral efficiency is the same independent of the number of DOFs and that the half-Gaussian distribution is the optimum distribution. We are able to thus obtain a compact equation for spectral efficiency which behaves in a similar way to the Shannon capacity formula but with the SNR scaled by a constant. We also show that for low SNR the half-Gaussian distribution is not the optimum distribution as the slope of the mutual information changes with the square of SNR which would lead to the number of photons per bit becoming infinite in the limit of SNR going to zero. We use a modified half-Gaussian distribution which has a discrete component (an impulse function at the origin) and provide a simple proof that this distribution results in a mutual information that goes to zero linearly with SNR resulting in a minimum number of photons per bit. Furthermore, by increasing the magnitude of the discrete component at the origin, it is shown that the minimum number of photons per bit for the incoherent channel approaches that of the coherent channel. / Ph. D.
266

One School Division's Experiences in Developing and Sustaining Capacity for School Improvement

Meade, LaDonna K. 12 December 2007 (has links)
All states and the District of Columbia have embraced academic standards as a primary means for improving public education (Manzo, 2001). Virginia implemented the Standards of Learning assessments in 1998. These assessments are based on a set of standards set forth by the Virginia Board of Education, and as of 2004, these assessments played a role in determining whether students received a high school diploma and whether a school received accreditation. The purpose of this study was to review the efforts of one Virginia school system to develop and sustain its capacity to improve student achievement in response to increased accountability. Bronfenbrenner's (1979) ecological system framework provided a lens through which to study building capacity and improving a school system, a school, and individual classrooms. This multi-level perspective provided a means to study various aspects of school improvement in response to federal, state, and local policies. This researcher utilized qualitative research methods to investigate a school division that has been successful in building and sustaining capacity to improve its schools. The findings are presented in six major themes that describe how this system built and sustained the capacity to achieve state accreditation. These themes are (a) aligning curriculum to the state standards, (b) providing professional development, (c) fostering relationships, (d) promoting the use of technology, (e) building on strengths, and (f) sharing leadership. The six themes were evident across every subsystem n this school division, from classroom, to schoolhouse, to central office in response to state and federal policies of accountability. / Ed. D.
267

Operational Analysis of Alternative Intersections

Sangster, John 09 September 2015 (has links)
Alternative intersections and interchanges, such as the diverging diamond interchange (DDI), the restricted crossing u-turn (RCUT), and the displaced left-turn intersection (DLT), have the potential to both improve safety and reduce delay. However, partially due to lingering questions about analysis methods and service measures for these designs, their rate of implementation remains low. This research attempts to answer three key questions. Can alternative intersections and interchanges be incorporated into the existing level of service and service measure schema, or is a new service measure with an updated level of service model required? Is the behavior of drivers at alternative intersections fundamentally similar to those at conventional intersections, such that traffic microsimulation applications can accurately model the behaviors observed in the field? Finally, is the planning level tool made available through FHWA an accurate predictor of the relative performance of various alternatives, or is an updated tool necessary? Discussion and case study analysis are used to explore the existing level of service and service measure schema. The existing control delay measure is recommended to be replaced with a proposed junction delay measure that incorporates geometric delay, with the existing level of service schema based on control type recommended to be replaced by a proposed schema using demand volume. A case study validation of micro- and macroscopic analysis methods is conducted, finding the two microscopic methods investigated to match field observed vehicle delays within 3 to 7 seconds for all designs tested, and macroscopic HCM method matching within 3 seconds for the DDI, 35 seconds for the RCUT, and 130 seconds for the DLT design. Taking the critical lane analysis method to be a valid measure of operations, the demand-volume limitations of each alternative design is explored using eighteen geometric configurations and approximately three thousand volume scenarios, with the DLT design predicted to accommodate the highest demand volumes before failure is reached. Finally, six geometries are examined using both the planning-level tool and the validated microsimulation tool, finding that the curve of the capacity-to-delay relationship varies for each alternative design, invalidating the use of critical lane analysis as a comparative tool. / Ph. D.
268

Multishot Capacity of Adversarial Networks

Shapiro, Julia Marie 08 May 2024 (has links)
Adversarial network coding studies the transmission of data over networks affected by adversarial noise. In this realm, the noise is modeled by an omniscient adversary who is restricted to corrupting a proper subset of the network edges. In 2018, Ravagnani and Kschischang established a combinatorial framework for adversarial networks. The study was recently furthered by Beemer, Kilic and Ravagnani, with particular focus on the one-shot capacity: a measure of the maximum number of symbols that can be transmitted in a single use of the network without errors. In this thesis, both bounds and capacity-achieving schemes are provided for families of adversarial networks in multiple transmission rounds. We also demonstrate scenarios where we transmit more information using a network multiple times for communication versus using the network once. Some results in this thesis are joint work with Giuseppe Cotardo (Virginia Tech), Gretchen Matthews (Virginia Tech) and Alberto Ravagnani (Eindhoven University of Technology). / Master of Science / We study how to best transfer data across a communication network even if there is adversarial interference using network coding. Network coding is used in video streaming, autonomous vehicles, 5G and NextG communications, satellite networks, and Internet of Things (IoT) devices among other applications. It is the process that encodes data before sending it and decodes it upon receipt. It brings advantages such as increased network efficiency, improved reliability, reduced redundancy, enhanced resilience, and energy savings. We seek to enhance this valuable technique by determining optimal ways in which to utilize network coding schemes. We explore scenarios in which an adversary has partial access to a network. To examine the maximum data that can be communicated over one use of a network, we require the intermediate parts of the network process the information before forwarding it in a process called network decoding. In this thesis, we focus on characterizing when using a network multiple times for communication increases the amount of information that is received regardless of the worst-case adversarial attack, building on prior work that shows how underlying structure influences capacity. We design efficient methods for specific networks, to communicate at capacity.
269

An improved scoring system for the Available Motions Inventory (AMI)

Nerhood, Robert C. 10 July 2009 (has links)
The role of engineering in the rehabilitation of the disabled has been steadily increasing in recent years. With the enactment of the Americans with Disabilities Act, that role has taken on a new level of importance. Uncomfortable with the qualitative, disability-oriented assessment tools of their special education, occupational and physical therapists, and medical teammates, engineers have come to rely more and more on their own quantitative assessment devices. Among these, the Available Motions Inventory (AMI) has shown great promise as a tool for the development of job modifications for the moderately disabled individual. From its seventy-one sub-tests, the AMI provides raw and processed data on an individual's capability to manipulate switches, orient settings, and demonstrate strength, as well as perform light assembly tasks. Included in the output is a weighted set of scores showing the subject's strength, range of motion, and reach/reaction capabilities. However, the AMI has its drawbacks. The scoring algorithms can underestimate the capabilities of subjects who fail to perform certain tasks, and it will not permit recombination or selective omission of the various sub-tests. This study examined the feasibility of employing the AMI analysis algorithms using a spreadsheet format for the purpose of better analyzing the data generated by persons with limited range of motion disabilities. Ten Subject Matter Experts (SMEs) were asked to analyze a series of data profiles and place the individuals described by the profiles into one of four job options. The data profiles are the AMI scores for individuals falling into one of three categories of disability: normal, hemiplegic, and limited range of motion. The jobs increase in difficulty from a position of non-feasible employment to employment as a pizza chef. The data generated were analyzed using the Sign Test. The results showed that a difference does exist between the current scoring system and the updated system in the placement of individuals. A difference between the systems was established for the case involving individuals with a limited range of motion. More importantly, the SMEs frequently chose more complex jobs for individuals with limited range of motion, suggesting that the new system provides a more realistic picture of this category of disabled persons. The results of this research permit a more effective use of the AMI by implementing an updated scoring system. The new system allows for several increased benefits during analysis. The scoring system is based on an EXCEL spreadsheet, thus it is operable in both the PC, Windows and Apple environments. Better data control and manipulation allows for better representation of an individual's capabilities. The system operates in the same manner as the existing system; however, the spreadsheet design allows for customization of the data output. Finally, it is believed that the use of the new system will increase the chance of job placement for severely disabled individuals with a limited range of motion. / Master of Science
270

Building Teacher Leadership Capacity Through School-Level Supports and Professional Development: Teachers' and Principals' Perspectives

Harding, Lisa Ann 05 April 2017 (has links)
The job of principals is demanding and evolving; consequently, they cannot lead alone. Teacher leaders can be a valuable resource if principals know how to build leadership capacity in teachers and practice distributive leadership. Understanding principals' and teachers' perceptions of their needs and how to best meet these needs can aid principals in building, and sustaining teacher leadership capacity. Therefore, the purpose of this qualitative study was to identify principals' and teachers' perceptions of their need and efforts to build teacher leadership capacity through school-level supports and professional development as well as principals' and teachers' perceptions of their ability to act as teacher leaders having participated in school-level professional development. Existing literature on building teacher leadership and sharing leadership responsibilities as it relates to the role of the principal, professional development, and sustainability was reviewed. Qualitative data were collected from 18 teachers and six principals in teacher focus groups and individual principal interviews in six high schools in one division in southeastern Virginia. At the conclusion of the data collection process, the researcher examined the perceptions of the teachers and the principals. The analysis revealed principals' and teachers' perceptions about the following areas: formal and informal leadership roles; professional development opportunities, teacher leadership structures in schools, strategic plans for building teacher leadership, mentor relationships between principals and teachers, barriers to teacher leadership, and recommendations for improved professional development opportunities. The study reinforced the notion that school-level supports and professional development need to be systematic and strategic. / Ed. D.

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