• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 76
  • 48
  • 37
  • 19
  • 12
  • 7
  • 7
  • 5
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 260
  • 107
  • 94
  • 70
  • 35
  • 26
  • 23
  • 22
  • 22
  • 21
  • 21
  • 21
  • 20
  • 17
  • 17
  • 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.
101

How we do it—the use of peritoneal patches for reconstruction of vena cava inferior and portal vein in hepatopancreatobiliary surgery

Radulova-Mauersberger, O., Distler, M., Riediger, C., Weitz, J., Welsch, T., Kirchberg, J. 27 February 2024 (has links)
Purpose Extended resections in hepatopancreatobiliary (HPB) surgery frequently require vascular resection to obtain tumor clearance. The use of alloplastic grafts may increase postoperative morbidity due to septic or thrombotic complications. The use of suitable autologous venous interponates (internal jugular vein, great saphenous vein) is frequently associated with additional incisions. The aim of this study was to report on our experience with venous reconstruction using the introperative easily available parietal peritoneum, focusing on key technical aspects. Methods All patients who underwent HPB resections with venous reconstruction using peritoneal patches at our department between January 2017 and November 2021 were included in this retrospective analysis with median follow-up of 2 months (IQR: 1–8 months). We focused on technical aspects of the procedure and evaluated vascular patency and perioperative morbidity. Results Parietal peritoneum patches (PPPs) were applied for reconstruction of the inferior vena cava (IVC) (13 patients) and portal vein (PV) (4 patients) during major hepatic (n = 14) or pancreatic (n = 2) resections. There were no cases of postoperative bleeding due to anastomotic leakage. Following PV reconstruction, two patients showed postoperative vascular stenosis after severe pancreatitis with postoperative pancreatic fistula and bile leakage, respectively. In patients with reconstruction of the IVC, no relevant perioperative vascular complications occurred. Conclusions The use of a peritoneal patch for reconstruction of the IVC in HPB surgery is a feasible, effective, and low-cost alternative to alloplastic, xenogenous, or venous grafts. The graft can be easily harvested and tailored to the required size. More evidence is still needed to confirm the safety of this procedure for the portal vein regarding long-term results.
102

ITS VEHICLE SUBSYSTEM BASED ON GPRS

Zhang, Zhengxuan, Zhang, Qishan 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The IMS(In-vehicle Monitoring Subsystem) of VMS(Vehicle Monitoring System) is the multifunctional and complex integrate embedded system, which sends the data of various in-vehicle devices to MC(Monitoring Center) and accepts commands and schedules from there. Using GPRS platform in this system make it possible for real-time and effective data transmission. This paper proposes some new insights on IMS applied to public traffic, including its software and hardware composition, and its realization method.
103

An empirical investigation of measures to enhance intra-Africa trade

Wang'ombe, Wangari January 2013 (has links)
Trade is largely considered a driving force of economic growth and development of nations. To this end, there is vast and far-reaching research on the subject, especially on matters international. However, research on intra-African trade is lacking in comparison to research on trade amongst the rest of the world, not just developed, but also developing countries alike. That aside there are numerous efforts put in place to enhance and encourage trade within and without the continent. The research presented in this thesis aims to investigate and address three key issues specific to intra-Africa trade. The questions asked are: are the measures currently in place successful in the promotion of intra-Africa trade; is the continent ready for measures about to be implemented and after all that, is trade really the key driving force for economic growth and development within Africa? To answer these questions, the research presented here in this thesis employs the gravity modelling approach, the G-PPP test and develops a macro-economic model which is applied to the Kenyan economy. The results indicate that; yes, trade is significant and important in determining economic growth, and while measures taken thus far such as the creation of Economic Integrations have not been as successful as was envisioned, trade openness continues to be among the most important ways in which trade is encouraged and enhanced, to this end, although the continent is yet to fulfil all the requirements for the formation of a full-blown Economic Union, it is ready for drastic measures such as the formation of a currency union. Literature reveals that this could form the basis of hastening complete integration and harmonization of all systems of the participating economies, thereby benefiting not just trade but also all other sectors of the economies.
104

Common Features in Vector Nonlinear Time Series Models

Li, Dao January 2013 (has links)
This thesis consists of four manuscripts in the area of nonlinear time series econometrics on topics of testing, modeling and forecasting nonlinear common features. The aim of this thesis is to develop new econometric contributions for hypothesis testing and forecasting in these area. Both stationary and nonstationary time series are concerned. A definition of common features is proposed in an appropriate way to each class. Based on the definition, a vector nonlinear time series model with common features is set up for testing for common features. The proposed models are available for forecasting as well after being well specified. The first paper addresses a testing procedure on nonstationary time series. A class of nonlinear cointegration, smooth-transition (ST) cointegration, is examined. The ST cointegration nests the previously developed linear and threshold cointegration. An Ftypetest for examining the ST cointegration is derived when stationary transition variables are imposed rather than nonstationary variables. Later ones drive the test standard, while the former ones make the test nonstandard. This has important implications for empirical work. It is crucial to distinguish between the cases with stationary and nonstationary transition variables so that the correct test can be used. The second and the fourth papers develop testing approaches for stationary time series. In particular, the vector ST autoregressive (VSTAR) model is extended to allow for common nonlinear features (CNFs). These two papers propose a modeling procedure and derive tests for the presence of CNFs. Including model specification using the testing contributions above, the third paper considers forecasting with vector nonlinear time series models and extends the procedures available for univariate nonlinear models. The VSTAR model with CNFs and the ST cointegration model in the previous papers are exemplified in detail,and thereafter illustrated within two corresponding macroeconomic data sets.
105

Integration genom nätverk : Om hur nätverk mellan den offentliga och privata sektorn kan förbättra arbetskraftsintegrationen.

Granstrand, Oscar, Ahmed, Osman January 2017 (has links)
No description available.
106

Common features in vector nonlinear time series models

Li, Dao January 2013 (has links)
This thesis consists of four manuscripts in the area of nonlinear time series econometrics on topics of testing, modeling and forecasting nonlinear common features. The aim of this thesis is to develop new econometric contributions for hypothesis testing and forecasting in thesearea. Both stationary and nonstationary time series are concerned. A definition of common features is proposed in an appropriate way to each class. Based on the definition, a vector nonlinear time series model with common features is set up for testing for common features. The proposed models are available for forecasting as well after being well specified. The first paper addresses a testing procedure on nonstationary time series. A class of nonlinear cointegration, smooth-transition (ST) cointegration, is examined. The ST cointegration nests the previously developed linear and threshold cointegration. An F-type test for examining the ST cointegration is derived when stationary transition variables are imposed rather than nonstationary variables. Later ones drive the test standard, while the former ones make the test nonstandard. This has important implications for empirical work. It is crucial to distinguish between the cases with stationary and nonstationary transition variables so that the correct test can be used. The second and the fourth papers develop testing approaches for stationary time series. In particular, the vector ST autoregressive (VSTAR) model is extended to allow for common nonlinear features (CNFs). These two papers propose a modeling procedure and derive tests for the presence of CNFs. Including model specification using the testing contributions above, the third paper considers forecasting with vector nonlinear time series models and extends the procedures available for univariate nonlinear models. The VSTAR model with CNFs and the ST cointegration model in the previous papers are exemplified in detail, and thereafter illustrated within two corresponding macroeconomic data sets.
107

Empirischer Vergleich von KBV und ÖPP

Hesse, Mario, Lück, Oliver, Redlich, Matthias, Rottmann, Oliver 03 April 2017 (has links) (PDF)
Seit einigen Jahren erfolgt in Deutschland eine verstärkte Einbindung von privatwirtschaftlichen Akteuren bei der Bereitstellung öffentlicher Leistungen. Insbesondere im Bereich der Infrastrukturbereitstellung haben sich Öffentlich-Private-Partnerschaften als eine alternative Beschaffungsvariante etabliert. Diese Vertrags-ÖPP sind in den Kontext einer allgemeinen Privatisierungskritik geraten, vor allem wird die Wirtschaftlichkeit dieser Variante bzw. deren Berechnung diskutiert. Vor diesem Hintergrund liegt das Ziel der Studie darin, die geringe empirische Datenlage zum Status quo der Umsetzungspraxis zu vergrößern, die Beschaffungsalternativen konventionelle Beschaffungsvariante (KBV) und ÖPP komparativ gegenüberzustellen und dabei auch auf Aspekte einzugehen, die im Erfahrungsbericht der Rechnungshöfe nicht behandelt werden, da dieser ausschließlich die Wirtschaftlichkeit von ÖPP fokussiert. Der Untersuchungsgegenstand fokussiert nur kommunale ÖPP-Projekte die einen Lebenszyklusansatz verfolgen, folglich Infrastruktureinrichtungen wie Schulen, Kindertagestätten und Verwaltungsgebäude. Allen diesen Projekten ist inhärent, dass während der Vertragslaufzeit kein öffentliches Eigentum veräußert wird, die Aufgabenverantwortung folglich stets bei der öffentlichen Hand verbleibt und somit auch keine Privatisierung öffentlichen Eigentums erfolgt. Die Studie zeigt, dass bei vielen KBV-Projekten die Betriebskosten in den anfänglich zu erstellenden Wirtschaftlichkeitsvergleichen keine oder nur eine untergeordnete Rolle spielen, während bei ÖPP in der Regel von Anfang an der gesamte Lebenszyklus der Infrastruktureinrichtung betrachtet wird, da der Großteil der Gesamtkosten der Infrastrukturmaßnahme während der Betriebsphase anfällt. (Kostensparende) Synergieeffekte bleiben deshalb bei den KBV vielfach ungenutzt. Die Nutzung von ABC-Ausschreibungen löst dieses Problem nur bedingt, da durch sie Aufwand und Transaktionskosten enorm gesteigert werden. Die Betrachtung unterschiedlicher Wertschöpfungsstufen (Planung, Bau, Finanzierung, Betrieb, Verwertung) stellt den entscheidenden Punkt für die Wirtschaftlichkeit von ÖPP-Projekten im Vergleich zur KBV dar, da die private Seite veranlasst ist, die Bauleistungen betriebsoptimierend zu planen und durchzuführen. Ferner zeigt die Studie, dass die von den Rechnungshöfen angemahnte Verfahrenstransparenz eine Herausforderung bei allen öffentlichen Beschaffungsvarianten darstellt und das Fehlanreize, die durch die Prinzipal-Agent-Problematik entstehen, ebenfalls kein singuläres Defizit des ÖPP-Ansatzes sind. Dem Vorwurf, dass ÖPP-Projekte dazu genutzt würden, Schulden in öffentlichen Haushalten zu verschleiern und Kosten möglichst intransparent darzustellen, wird mit der schrittweisen bundesweiten Umstellung der Kommunen auf doppische Haushaltsführung weitestgehend der Boden entzogen, da ÖPP-Projekte mit Forfaitierung sogar Transparenzvorteile gegenüber den KBV aufweisen. Ziel der Studie ist nicht, die ÖPP als „Königsweg“ der öffentlichen Beschaffung darzustellen, sondern den Versuch zu unternehmen, einen kritischen Blick auf die Beschaffungsvariante selbst und die an ihr geäußerte Kritik zu werfen. Es gilt: Vor dem Hintergrund der langfristigen Bindung des privaten Partners und der damit verbundenen Verantwortungs- und Risikoteilung ist es nach wie vor möglich, dass wirtschaftlichere und bedarfsgerechtere Lösungen als bei der KBV gefunden werden.
108

Potencialidades e limites para o desenvolvimento de situações de aprendizagem mediadas pelas Tecnologias Digitais da Informação e Comunicação no ciclo de alfabetização

Ferreira, Marinalva da Silva 04 July 2017 (has links)
Submitted by FERNANDA DA SILVA VON PORSTER (fdsvporster@univates.br) on 2018-01-05T12:53:59Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 2017MarinalvadaSilvaFerreira.pdf: 3049800 bytes, checksum: 6c390ab18fe0c874646b51d8dda96682 (MD5) / Approved for entry into archive by Ana Paula Lisboa Monteiro (monteiro@univates.br) on 2018-01-05T17:32:27Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 2017MarinalvadaSilvaFerreira.pdf: 3049800 bytes, checksum: 6c390ab18fe0c874646b51d8dda96682 (MD5) / Made available in DSpace on 2018-01-05T17:32:27Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) 2017MarinalvadaSilvaFerreira.pdf: 3049800 bytes, checksum: 6c390ab18fe0c874646b51d8dda96682 (MD5) Previous issue date: 2018-01 / Em razão do avanço tecnológico, faz-se necessário refletir sobre o uso das Tecnologias Digitais da Informação e Comunicação (TDICs) como recurso pedagógico nos processos de ensino e aprendizagem. Nesse contexto, o objetivo geral da pesquisa foi investigar as potencialidades e os limites que o professor do Ciclo de Alfabetização tem encontrado para o desenvolvimento de situações de aprendizagem mediadas pelas Tecnologias Digitais da Informação e Comunicação na Rede Pública Municipal de Imperatriz/MA. Para tanto, a investigação foi realizada de acordo com a abordagem qualitativa, e, entre os vários tipos de pesquisa desta abordagem, a opção foi por uma aproximação com a pesquisa-ação de Barbier (2007) e Thiollent (2011), tendo como finalidade a interação com a escola pesquisada e a Professora participante da pesquisa. Como instrumentos, utilizaram-se a entrevista semiestruturada; a observação participante ativa; o diário de itinerância para os registros das percepções em todos os espaços e experiências vivenciadas, as reflexões, dados pesquisados, curiosidades percebidas durante todas as etapas do estudo. Ademais, usou-se a análise documental, que permitiu a aproximação com o Projeto Político Pedagógico da escola, e os Planos de Ensino da Professora pesquisada, além de registros fotográficos. A investigação foi pautada em estudos que tratam do uso das TDICs na educação, como os de Levy (2011), Demo (2009), Kenski (2015), Prensky (2001), Moran (2015), entre outros. Os referidos autores não apontam as Tecnologias Digitais como redentoras dos problemas educacionais, tampouco defendem a ideia de que, sem elas, é impossível fazer educação, mas apresentam propostas de as integrar com as práticas pedagógicas, compreendendo que podem servir de suporte à realização da leitura e compreensão do mundo e dos afazeres sociais da contemporaneidade, exigindo, assim, uma nova postura da escola e do professor quanto à exploração das Tecnologias Digitais da Informação e Comunicação na educação. Os resultados da pesquisa apontam que: a) No PPP da escola pesquisada, as TDICs são compreendidas como fatores de desenvolvimento e mudanças e ferramentas que podem favorecer a inclusão, além de serem tratadas como um dos desafios da contemporaneidade para a formação de professores. No Marco Operacional do PPP, não há referências ao uso das TDICs nos Anos Iniciais, embora estejam presentes no Plano de Ensino da Professora pesquisada, que atuava no primeiro ano do Ensino Fundamental; b) Apesar de alguns limites, como a falta de computadores em quantidade suficiente para um trabalho individual e/ou em pequenos grupos, a ausência de fones de ouvidos a lentidão da internet, foi possível observar várias possibilidades de uso das TDICs em situações de aprendizagem, a saber: o vídeo, as Histórias em Quadrinhos – HQ, as planilhas eletrônicas e o Software de apresentação. Destaca-se assim a importância do uso pedagógico das TDICs nas situações de aprendizagem, além de apontar a escola como local onde é possível também aprender a utilizar socialmente as tecnologias digitais. / Due to the technological advance, it is necessary to reflect on the use of Digital Information and Communication Technologies (TDICs) as pedagogical resources in the teaching and learning processes. In this context, the general objective of the research was to investigate the potentialities and the limits that the teacher of the Literacy Cycle has found for the development of learning situations mediated by the Digital Information and Communication Technologies in the Municipal Public Network of Imperatriz / MA. To do so, the research was carried out according to the qualitative approach, and among the various types of research of this approach, the choice happened by an approach with the action research, of Barbier (2007) and Thiollent (2011), having as purpose the interaction with the researched school and the teacher participating in the research. As instruments, the semi-structured interview was used; the active participant observation; the roaming journal for the records of perceptions in all spaces and experiences, the reflections, researched data, curiosities perceived during all stages of the research. Besides, it was used the documentary analysis that allowed the approach to the School's Political Pedagogical Project and the Teaching Plans of the Researcher, in addition to photographic records. The research was based on studies that deal with the use of the TDICs in education, such as Levy’s (2011), Demo’s (2009), Kenski’s (2015), Prensky’s (2001) and Moran’s (2015) among others. These authors do not point neither to digital technologies as redeeming educational problems, nor they defend the idea that it is not possible to do education without them, but they present proposals for the interaction of these technologies with the pedagogical practices, understanding that they can support the realization of the reading and understanding of the world and the social affairs of contemporaneity, and thus require a new posture of the school and the teacher regarding to the exploitation of Digital Technologies of Information and Communication in education. The research results show that: a) In the PPP of the researched school, the TDICs are understood as a factors of development, changes; and tools that can enable inclusion, as well as being treated as one of the contemporary challenges for the teacher training. In the PPP Operational Framework, there are no references for the use of TDICs in the Early Years, although they are present in the Teaching Plan of the researched Teacher who worked in the first year of the Elementary Education; b) In spite of some limitations, such as the lack of sufficient computers for individual work and / or small groups, the absence of earphones and the slowness of the internet, it was possible to observe several possibilities of using the TDICs in learning situations, the Know: the video, the Comics - HQ, the spreadsheets and the Presentation Software. This highlights the importance of the pedagogical use of TDICs in learning situations, as well as pointing out the school as a place where it is also possible to learn how to use digital technologies socially.
109

Public Private Partnerships in road transport infrastructure in India : a governance perspective

Verma, Manisha January 2012 (has links)
Public Private Partnerships, or PPPs, are being increasingly preferred by governments across the world for filling the infrastructure deficit, as they are claimed to provide access to private capital, and bring private sector efficiencies in provisioning of public services. In India too, a distinct policy shift towards PPPs in various sectors has been observed accompanied by a high degree of reliance on such partnerships to upscale the transport infrastructure. A growing body of literature however reveals serious flaws in the claims of economic superiority, effectiveness and profitability of the PPPs. They are being questioned on various accounts of transparency, accountability, equity, and excessive profiteering by the private partners. This gives rise to an advocacy for the enhanced role of the State in governance of PPPs. In this background, this research explores the nature of division of roles and responsibilities, allocation of risks and sharing of benefits by the State and the private partners within the PPPs in the context of road transport sector in India. It further examines the extent of investment of resources by the private partners in the projects. The factors shaping PPPs in road transport in India are also examined. This research suggests measures to strengthen the structures and mechanisms within the public and private partners to improve public infrastructure within the PPP framework. In order to achieve the research aims, and to gain a deeper perspective of the governance issues of PPPs from different administrative levels, two national and two state highways (one in construction while the other in operational stage in both cases) along with an intra-city transport project, part of which is already operationalised, were selected for the study. This study is rooted in critical realism according to which understanding of any social phenomenon can be achieved through study of the underlying multi-layered structures and mechanisms which cause the phenomenon. Research findings reveal that while PPP projects in highways largely followed the theoretical model of PPPs, the urban transportation project was found to be substantially deviating from a general PPP model discussed in the literature due to the unique requirements of urban transport infrastructure in India. The widely accepted argument of PPPs bringing in private capital to public services has been debunked by the Ahmedabad Bus Rapid Transit System (ABRTS). The project is substantially funded by the national and state governments due to limited incentives for the private sector to invest in these projects under BOT mode. The under-developed capability within the private sector in urban transportation projects in India resulted in unbundling of services rather than one private agency providing all of them. The local urban body has retained several risks as it more suitably located to bear them more efficiently. In the PPPs in highways, the public partner has shifted many of its responsibilities to the concessionaire primarily due to shortage of adequate manpower with the public partner, and the incentive of timely completion of the project with the private partner. Adoption of the PPP mode in highways has not been able to avoid time and cost over-runs, largely due to the public partners not meeting their share of responsibilities. Land acquisition has emerged as the single most contentious issue of PPPs in infrastructure in India and is the major cause for delay in PPP projects. In addition, serious issues in land-grabbing and profiteering by the private partners have also been observed. A more active role of the State in PPPs is suggested to improve the delivery of public services through the PPP mode. This may require establishing additional structures and mechanisms of governance to meet the emerging requirements of these new modes of procurement, and to strengthen the existing ones.
110

New decision support systems for Public Private Partnership projects

Rajabi, Mohammad January 2017 (has links)
It is well established that one of the key contributing factors to the growth of countries’ economies is the existence of appropriate economic and social infrastructures. The setup of these infrastructures and their operation or delivery of public services associated with them have proved to be a costly and often unaffordable business for most governments. Therefore, private sector participation in the delivery of public services has been opted for by governments under Public-Private Partnerships (PPPs). Additional reasons for the public sector to choose a PPP framework to deliver public services include the public sector representatives’ lack of sufficient technical knowledge and specifications required by most projects; the required amount of investment to implement such projects is too high to be affordable by the public sector alone; the increasing difficulties of predicting and controlling the uncertainties that typically govern the phases of such projects including the level of actual demand for the related services by the time the project is operational; the level of bureaucracy in the public sector and its implications on the time frame of decision-making processes; the relatively low efficiency in project execution by the public sector; and most importantly the fact that, in practice, these difficulties are often better managed by the private sector who seem to possess both the financial and the executive capabilities to undertake such projects Currently, there is a gap in the game theory literature on modelling PPP related decisions and issues. This thesis contributes to reducing such gap by proposing three novel and practice-oriented game theoretical models along with algorithms for solving them, namely an ordinal game for the shortlisting of potential private sector partners; two non-cooperative dynamic games for negotiation with shortlisted private sector partners and selection of private sector partner to award the PPP contract to; and a non-cooperative dynamic game for financial renegotiation post-PPP contract award. In sum, each novel game addresses an important problem faced by the private sector during the typical stages of the life cycle of PPPs, namely private sector partner selection at the tendering stage; negotiation between the public sector and shortlisted bidders to select the candidate to whom to award a PPP contract to at the post-tendering stage; and financial re-negotiation between the public sector and the selected private sector partner at the post-contract award stage.

Page generated in 0.0364 seconds