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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.
211

Open quantum system dynamics for describing state transfer

Zuniga-Hansen, Nayeli 01 May 2014 (has links)
In principle a quantum system could be used to simulate another quantum system. The purpose of such a simulation would be to obtain information about problems which are difficult to simulate on a classical computer due to the exponential increase of the Hilbert space with the size of the system, and which cannot be readily measured or controlled in an experiment. A quantum simulator is, however, an open quantum system that will interact with the surrounding environment, which in this case are other particles in the system, and will be implemented using imperfect controls, making it subject to noise. It has been suggested that noise does not need to be controlled to the same extent as it must be for general quantum information processing. However, the effects of noise in quantum simulations are not well understood and how best to treat them in most cases is not known. In the present work we study an existing quantum algorithm for the simulation of the one-dimensional Fano-Anderson model. This algorithm was proposed for a liquid-state NMR device. We examine models of noise in the evolution using different initial states in the original model. We also add interacting spins to simulate realistic situation where an environment of spins is present. We find that states which are entangled with their environment, and sometimes correlated but not necessarily entangled have an evolution which is described by maps which are not completely positive. We discuss the conditions for this to occur and also the implications.
212

Optimal control of fed-batch fermentation processes

Vanichsriratana, Wirat January 1996 (has links)
Optimisation of a fed-batch fermentation process typically uses the calculus of variations or Pontryagin's maximum principle to determine an optimal feed rate profile. This often results in a singular control problem and an open loop control structure. The singular feed rate is the optimal feed rate during the singular control period and is used to control the substrate concentration in the fermenter at an optimal level. This approach is supported by biological knowledge that biochemical reaction rates are controlled by the environmental conditions in the fermenter; in this case, the substrate concentration. Since an accurate neural net-based on-line estimation of the substrate concentration has recently become available and is currently employed in industry, we are therefore able to propose a method which makes use of this estimation. The proposed method divides the optimisation problem into two parts. First, an optimal substrate concentration profile which governs the biochemical reactions in the fermentation process is determined. Then a controller is designed to track the obtained optimal profile. Since the proposed method determines the optimal substrate concentration profile, the singular control problem is therefore avoided because the substrate concentration appears nonlinearly in the system equations. Also, the process is then operated in closed loop control of the substrate concentration. The proposed method is then called "closed loop optimal control". The proposed closed loop optimal control method is then compared with the open loop optimal feed rate profile method. The comparison simulations from both primary and secondary metabolite production processes show that both methods give similar performance in a case of perfect model while the closed loop optimal control provides better performance than the open loop method in a case of plant/model mismatch. The better performance of the closed loop optimal control is due to an ability to compensate for the modelling errors using feedback.
213

Proposta de biomodelagem virtual utilizando softwares livres

Silva, Fabio Francisco da [UNESP] 05 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-05Bitstream added on 2014-06-13T20:58:26Z : No. of bitstreams: 1 silva_ff_me_guara.pdf: 4729647 bytes, checksum: 7db1bd019b542d769c6c054a27719a6f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Biomodelagem é um termo genérico que designa a habilidade de replicar a morfologia de uma estrutura biológica em um modelo físico. Por ser uma técnica relativamente nova, sua disseminação é limitada pelo alto custo de aquisição de softwares proprietários e hardware de alto desempenho, impedindo sua utilização em hospitais públicos, centros de saúde e consultórios médicos. O objetivo principal desse trabalho é apresentar uma proposta de biomodelagem virtual através do uso de softwares livres instalados em equipamentos convencionais de informática e contribuir de forma efetiva para redução dos custos da técnica. Para atingir o objetivo, foi necessário identificar softwares livres dedicados e CAD que pudessem ser aplicados em conjunto para desenvolvimento de projetos em biomodelagem. Dentre a diversidade de programas disponíveis, observou-se que os softwares Invesalius 3.0 e FreeCAD 0.11 possuíam as características necessárias para aplicação da técnica. Baseado nos conceitos de biomodelagem, três estudos de caso foram abordados para elaboração do diagnóstico e planejamento cirúrgico, auxiliando o médico na tomada de decisões. Os resultados demonstraram que a biomodelagem virtual por meio do uso dos softwares livres Invesalius 3.0 e FreeCAD 0.11, instalados em equipamentos convencionais de informática, é viável para uso na rotina médica em diversas situações de diagnóstico e planejamento cirúrgico. As principais vantagens apresentadas são a redução dos custos em biomodelagem e a possibilidade de disseminação da técnica, permitindo a inclusão de um maior número de pacientes submetidos às tecnologias 3D / Biomodeling is a generic term for the ability to replicate the morphology of biological structure in a physical model. As it is a relatively new technique, its dissemination is limited by the high cost of purchase of proprietary software and high performance hardware, impeding their use in public hospitals, health centers and physician offices. The main objectives of this work are to propose a virtual biomodeling through the use of open source software installed in a conventional computer equipment and to effectively contribute in reducing the technique costs. In order to achieve the proposed objectives, it was necessary to identify dedicated open source software and CAD open source software that could be applied together to develop biomodeling projects. Among the variety of programs available, it was noted that the software InVesalius 3.0 and the FreeCAD 0.11 had the necessary characteristics for the application of the technique. Based on the concepts of biomodeling, three case studies were discussed for making the diagnosis and the surgical planning, assisting the physician in making decisions. The results showed that the virtual biomodeling through the use of the open source software called InVesalius 3.0 and FreeCAD 0.11, installed in conventional computer equipment, is feasible for the routine use in many situations of medical diagnostic and surgical planning. The main advantages are the cost reduction in biomodeling and the possibility of spreading the technique, allowing the inclusion of a greater number of patients subjected to 3D technologies
214

Jornalismo open source : discussão e experimentação do OhmyNews International

Brambilla, Ana Maria January 2006 (has links)
Ao propôr-se a discutir e experimentar o noticiário sul-coreano OhmyNews International, a presente dissertação recorre a princípios da complexidade, à engenharia de software e aos valores do jornalismo tradicional – bem como ao seu histórico – para elaborar um entendimento inicial de jornalismo open source. As diretrizes propostas são aplicadas ao objeto empírico por meio de observação participante, análise descritiva e entrevistas com grupos de pessoas envolvidas em diferentes aspectos do projeto. O foco central desta dissertação é a interação dos diferentes públicos com a notícia em ambiente digital. / To discuss and experiment the South-Korean news project OhmyNews International, this research uses complexity principles, software engineering and traditional journalism values – as well as it historic – to compose an initial agreement about open source journalism. Routes purposed are applied to empiric object through participatory observation, descriptive analysis and interviews to groups involved in deferent ways with project. The main goal of this research is the interaction between different people with news on digital environment.
215

Interaction and influences in an Open-Source eco system

Hermansson, Patrik January 2008 (has links)
The development of open source software has gone from a model characterized by skilled software developers that developed open source software for their own interest and their own needs to a model that is more business friendly and more attractive for companies and organizations. One new business model for open source software is the professional open source software model or OSS 2.0. The business model includes three roles: the open source project, the professional open source company and the user. This dissertation studies the relationship between these three roles and focuses on the development of the user role and how it may develop for a new user in a specific OSS ecosystem. The roles in the eco system that has been studied are taken by the open source project Alfresco, the professional open source company Redpill and a user from a large international company, without any previous experience of open source software or the business model of professional open source. The result of the study showed a well developed eco system between the open source project and the professional open source company but a need of more information about the user’s role in it. Open source software is still seen by the user as an unsafe and unsecure alternative to the proprietary software available and more information about the business model of professional open source software and how the user can interact and influence the eco system is still needed.
216

The restructuring of the Open Learning Agency: a predictive analysis

Nielsen, Mark L. 05 1900 (has links)
This paper presents a case study and analysis of changes in the organizational structure of the Open Learning Agency (OLA) of British Columbia in 1992. Under the aegis of the Ministry of Advanced Education, Technology and Training, the Agency carries a five-fold mandate - in collaboration with universities, institutions, boards of school trustees and other agencies concerned with education, OLA is to: provide an educational credit bank for students; coordinate the development of open learning education; use open learning methods to provide educational programs and services; carry out research related to open learning education; and operate one or more broadcasting undertakings devoted primarily to the field of educational broadcasting. The central question of the paper is: How will OLA restructure to achieve its mandate and strategic direction? In particular, the paper examines the Agency's structure prior to reorganization, the internal and external forces acting upon it as seen through the eyes of its executive members and the key issues facing the organization, including the reasons which precipitated a review of the organizational structure in 1991. The structure prior to reorganization is analyzed and classified as an example of Mintzberg's (1989) innovative configuration. The paper also predicts an innovative configuration for the Agency's reorganized structure based upon Mintzberg's contingency and life cycle hypotheses. The reorganized structure (which came into effect May 1, 1992) is subsequently analyzed and agrees with the prediction. The method of investigation included interviews with executive members conducted approximately three months prior and three months after the reorganization, archival research and personal observation by the writer, an employee of the Agency. Mintzberg's (1983, 1989) conceptual framework of structural configurations provided a basis for analysis of the case study data. The paper concludes that the innovative configuration is an appropriate form for the organization in view of its mandate and strategic direction but notes that it is also a difficult configuration to sustain, subject to pressures for increasing bureaucratization and susceptible to internal and external politicization. The paper recommends that the Agency do its best to maintain the configuration by educating staff about its nature and resist pressures which might shape it into a more conventional, professional form. The paper further finds Mintzberg's framework descriptive and helpful in providing limited, broad understanding of the Agency, its issues and choices for change; however, factors which can have significant impact such as political pressure, personal idiosyncrasies of leaders and centralization of office sites make any detailed prescriptions for organizational change somewhat elusive. / Education, Faculty of / Educational Studies (EDST), Department of / Graduate
217

Prezentace vybraných účetních a finančních informací státu ze systému CSÚIS pomocí zvolené BI open-source technologie / Presentation of the selcted public financial and accounting data from CSUIS system with open source BI technology

Bobkov, Pavel January 2011 (has links)
The inspiration of the thesis stands on general insufficient condition of the presentation of financial management and state budget for the public sector of the Czech Republic. Thesis deals with the presentation of selected accounting and financial information from the system CSÚIS and using selected open source BI technology for this purpose. The input is a data extract from the central state accounting information system (CSÚIS), which contains accounting records and financial statements of public entities. Logical data model created by using data obtained is followed by the proposed budget options data analysis and accounting at both the state and at a particular entity level. The next phase of work trying to implement the project requirements of open source Business Intelligence technologies (OSBI). The work includes market analysis of OSBI, and chooses the most appropriate tool to build the new presentation of state financial and accounting data.
218

Development of an Open Source Quadrupedal Robot Platform for Education: SmallKat

Bisland, Keion 17 May 2020 (has links)
In the field of robotics, quadrupedal robotics is a rapidly growing segment. Despite the large number of robotic quadrupeds developed so far, there is currently no platform specifically developed for use in an educational setting. Currently available quadrupeds have several aspects that restrict them to use only in the research labs that developed them, preventing them from being available for use in undergraduate-level classes. This constraint limits the number of people able to gain experience with these highly complex platforms. To enable further development into the field of quadruped robotics, more engineers with in-depth experience with these platforms and the knowledge required to develop and operate them are needed. In this thesis we present the SmallKat platform which strives to fill this space and allow for further development into the fields of dynamic quadruped robotics without the fear of damaging an expensive robot. This thesis proposes a robot designed specifically for the purpose of teaching multiple robotics concepts including kinematics, control, dynamics, trajectory planning, and gait generation. Like many other quadrupedal robots, SmallKat uses 3-DoF legs allowing for coordinated motion in all 3 axes. The size, modularity, cost, and capabilities of the platform are what suit it to teach at a variety of levels. With the integrated sensing and safety features, this platform lends itself to the development of an undergraduate robotics course on quadruped robots, a sample of which is discussed in this thesis. Through the distribution of the SmallKat robot to more schools and universities, the robotics curriculum offered by these universities could be expanded further to offer courses at the undergraduate level in legged robotics.
219

Řešení hostingových služeb na open source platformách / Solution of hosting services on open-service platforms

Matějíček, Ondřej January 2008 (has links)
The main point of this work is to describe complex solution of web-hosting server based on free software. This should provide main services such a post or www server. The work describes instalation of Unix(GNU/Linux) operating system. In addition are described individual services, evolved conrete implementations and also is spoken their installation and configuration. Though this text describe implementation of concrete application, some part of thist text contains generally information about installation, configuration and securing of linux servers.
220

Electronic Theses and Dissertations in Peru: A Twelve-Year Experience and Its connections to “LA REFERENCIA”, a Latin American Repository

Huaroto, Libio, Recavarren, Isabel 18 November 2015 (has links)
In June 2004, University of San Marcos (UNMSM, Lima, Peru) launched the first portal providing access to electronic theses and dissertations in Peru using the Cybertesis platform. This initiative marked the beginning of open access theses repositories in the country. It was followed by other higher education and research institutions, both public and private. Four years later, the Peruvian Network for Digital Theses was established. It was officially closed in December 2014. In June 2010, Red CLARA launched LA REFERENCIA, a project funded by Banco Interamericano de Desarrollo (BID). Eight regional countries were part of this initiative: Argentina, Brazil, Chile, Colombia, Ecuador, Mexico, Peru and Venezuela. El Salvador joined it recently. The aim of the project was to design a strategy for and an agreed framework on interoperability and scientific production management for Latin America. As of today, country members have developed national networks, each with its respective national repository portal. Repositories contain three (3) basic types of collections: master’s theses and doctoral dissertations; journal articles; and research projects. Participant institutions in LA REFERFENCIA are SNRD (Argentina), IBICT (Brazil), RRAAE (Ecuador), COLCIENCIAS, MEN, RENATA (Colombia), CONICYT, (Chile), CBUES (El Salvador), CONACYT, CUDI (México), RENARE (Peru), and CENIT, REACCIUN (Venezuela). Two events furthering open access to scientific research have been of key importance in Peru in the last two years; the first being the enacting of statute 30035 and its Regulations, by which the National Repository for Open Access Science and Technology was created. According to this legislation, all projects funded with public money will be openly accessible. The second event was the implementation of ALICIA (http://alicia.concytec.gob.pe), the aforementioned National Repository for Open Access Science and Technology. ALICIA is made up of 33 repositories – 13 of them are theses and dissertation repositories; 20 are institutional ones. ALICIA contains 34,567 registration records: 9,297 of them correspond to master’s theses, and 1,906 to doctoral dissertations (ALICIA has an additional 25,270 professional theses submitted by students after completing their undergraduate studies in order to obtain a professional license granted by the Peruvian state). LA REFERENCIA offers access to 88,599 doctoral dissertations and 202,798 master’s theses. Peruvian repositories for electronic theses and dissertations use DSpace, and have adopted the DRIVE 2.0 norms. Some institutions, like Universidad Peruana de Ciencias Aplicadas (UPC) have implemented Altmetrics indicators, showing social network activities connected to contents in theses, dissertations and journal articles.

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