• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2647
  • 1277
  • 667
  • 317
  • 292
  • 266
  • 252
  • 95
  • 94
  • 84
  • 70
  • 67
  • 55
  • 55
  • 55
  • Tagged with
  • 7617
  • 566
  • 554
  • 545
  • 530
  • 530
  • 491
  • 483
  • 464
  • 454
  • 450
  • 431
  • 422
  • 422
  • 398
  • 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.
171

Multi-area network analysis

Zhao, Liang 17 February 2005 (has links)
After the deregulation of the power systems, the large-scale power systems may contain several areas. Each area has its own control center and each control center may have its own state estimator which processes the measurements received from its local substations. When scheduling power transactions, which involve several control areas a system-wide state estimation solution is needed. In this dissertation, an estimation approach which coordinates locally obtained decentralized estimates while improving bad data processing capability at the area boundaries is presented. It is assumed that synchronized phasor measurements from different area buses are available in addition to the conventional measurements provided by the substation remote terminal units. The estimator with hierarchical structure is implemented and tested using different measurement configurations for two systems having 118 and 4520 buses. Furthermore, we apply this multi-area solution scheme to the problem of Total Transfer Capability (TTC) calculation. In a restructured power system, the sellers and buyers of power transactions may be located in different areas. Computation of TTC will then require system-wide studies. We investigate a multi-area solution scheme, which takes advantage of the system-wide calculated Power Transfer Distribution Factors (PTDF) in order for each area to calculate its own TTC while a central entity coordinates these results to determine the final value. The proposed problem formulation and its solution algorithm are presented. 30 and 4520 bus test systems are used to demonstrate the approach and numerically verify the proposed TTC calculation method.
172

A content analysis of reading strategies in teacher editions of mathematics textbooks

Takami, Linda J. January 2009 (has links) (PDF)
Thesis (Ed. D.)--Washington State University, December 2009. / Title from PDF title page (viewed on Dec. 28, 2009). "Department of Teaching and Learning." Includes bibliographical references (p. 96-110).
173

A handbook of content area reading strategies

Azevedo, Heather Robyn. January 2009 (has links)
Thesis (M.A.)--California State University, Chico. / Includes abstract. Includes bibliographical references (p. 63-65).
174

DESIGN AND TEST OF MULTIPLE NETWORKS ON A SINGLE BROADBAND CABLE PLANT

Wang, Kuochen, 1955- January 1986 (has links)
No description available.
175

Sistemi strutturali cellulari a pareti portanti in cemento armato gettato in opera realizzate con la tecnologia del pannello di supporto in polistirene / Cellular structural systems composed of cast in situ concrete walls created using the technique of the polystyrene support panel

Ricci, Ilaria <1984> 01 June 2012 (has links)
In questa Tesi di Dottorato di Ricerca sono state studiate le caratteristiche strutturali e le relative prestazioni dei sistemi strutturali cellulari a pareti tozze di tipo sandwich in c. a. gettato in opera realizzate con la tecnologia del pannello di supporto in polistirene. Tali sistemi strutturali sono caratterizzati da numerose peculiarità; infatti, (i) il comportamento globale delle strutture risulta essere di tipo cellulare, e, le pareti che costituiscono il sistema resistente alle azioni sia orizzontali che verticali risultano essere: (ii) tozze, (iii) di tipo sandwich e caratterizzate da: (iv) basse percentuali di armatura, (v) ridotti tassi di lavoro a sforzo assiale e (vi) stesso quantitativo di armatura orizzontale e verticale. Date le specificità dei sistemi strutturali in esame, si è, in primo luogo, cercato di inquadrare le peculiarità strutturali sopra elencate nell’ambito scientifico. Ciò ha consentito di riscontrare una profonda carenza nella conoscenza relativa al comportamento di tali strutture specialmente nei confronti delle azioni orizzontali di tipo sismico. Pertanto i due principali obiettivi di questa Tesi di Dottorato sono stati: (1) la sistematizzazione scientifica e la relativa interpretazione di 10 anni di prove sperimentali condotte sul sistema strutturale in esame; e (2) la progettazione, la realizzazione e l’interpretazione preliminare dei risultati di una prova su tavola vibrante di una struttura a tre piani con pianta rettangolare, realizzata con la tecnologia del pannello di supporto in polistirene (la prova è stata effettuata nell’ambito del progetto di ricerca Europeo SERIES). Questa ricerca ha dunque consentito di far luce sul comportamento (in particolar modo, nei confronti delle azioni orizzontali di tipo sismico) dei sistemi strutturali composti da pareti tozze di tipo sandwich in c. a. gettato in opera realizzati con la tecnologia del pannello di supporto in polistirene. / In this Ph.D. Thesis the structural characteristics and the corresponding performances of cellular structural systems composed of cast in situ concrete walls created using the technique of the polystyrene support panel have been studied. Such structural systems are characterized by many peculiarities; in fact, (i) the overall behavior of the structures is cellular; and, the walls, which composed the vertical and the lateral resisting system, are (ii) squat, (iii) sandwich and characterized by: (iv) light amount of reinforcement, (v) low values of vertical stresses, (vi) the same amount of vertical and horizontal reinforcement. Given the specific characteristics of the structural system at hand, first of all, all these peculiarities have been set in a scientific background. As a result, a deep lack of knowledge about the structural behavior (especially with respect to lateral seismic forces) of these structures has been discovered. For this reason the main objectives of this Ph.D. Thesis are (1) the scientific systematization and the corresponding interpretation of 10 years of experimental test performed on the structural system at hand; and (2) the design, the realization and the preliminary interpretation of the results of a shaking table test carried out on a 3-story structure composed of cast in situ sandwich concrete walls (it is part of the European Research Project SERIES). This research has allowed to understand the structural behavior of the structural systems composed of cast in situ sandwich concrete walls, especially with respect to lateral seismic forces.
176

Nežinomų teritorijų tyrinėjimas naudojant savaeigius robotizuotus mechanizmus / Unknown area coverage using autonomous robots

Zachaževski, Stanislav 25 November 2010 (has links)
Nežinomo ploto dengimas yra aktuali ir paplitusi problema. NPD sprendimas realiuose robotuose susiduria su daviklių ir mechanizmų netikslumu. Atliktame darbe yra pateiktas „Bouncing“ NPD algoritmo sprendimas robotui, turinčiam mažo tikslumo daviklius ir neprecizinius valdiklius. Taip pat atliktas darbas parodė sudėtingus roboto kūrimo aspektus ir galimus sprendimus. Sukurtas robotas dėl pigumo ir nesudėtingos realizacijos gali būti naudojamas kaip platforma kitokių algoritmų tyrimui. / The problem of unknown area coverage with mobile robots has received considerable attention over the past years. This problem is a common challenge in many applications, including automatic lawn mowing and vacuum cleaning. However, most of the approaches find difficult to implement in real life because of problems of environment data reading. In this paper we consider the problem of robust area covering algorithm implementation in mobile robot. The chosen approach is based on simple and robust algorithm for uncertain environment and simple robot platform. The results showed robustness, reliability of chosen method of control. The constructed robot has shown simplicity, cheapness of creation and possibility for different algorithm testing. The significance of this paper lies in the practical solution for robust mobile robot area coverage, suitable for noisy environment and low precisions robot sensors.
177

Every Teacher a Teacher of Reading?: A Systematic Literature Review of Content-Area Literacy

Scott, Chyllis Elayne 16 December 2013 (has links)
Appropriate preparation for preservice and inservice teachers for teaching content-area literacy continues to influence twenty-first century research agendas. In this systematic review (which analyzed 2,179 articles), the researcher aimed to ascertain and synthesize the research on teacher preparation for content-area literacy instruction while evaluating the methodological qualities of the research. The findings are presented in an article format with the connecting theme of content-area literacy; however, the first article focused on research regarding preservice teachers and the second article on inservice teachers. Whereas, previous reviews have primarily focused on secondary teacher beliefs and attitudes this review provides a broader scope of the research, which encompasses K-16 preservice and inservice teachers’ beliefs, attitudes, instructional practices, strategies, and knowledge of content-area literacy instruction. The major findings from research on preservice teachers are: with a minimum of one content-area literacy course, this teacher preparation may prove to be less than sufficient; in addition, preservice teachers’ beliefs regarding content-area literacy are typically positive, but actual transference once in the classroom is narrow. The major findings from the inservice article suggest the need for further training, modeling, and collaboration of literacy instruction for implementation in content classes. Inservice teachers, albeit experts of their content are restricted by their own motivation and knowledge of literacy strategies, therefore literacy implementation during class instruction is restricted. By reviewing longitudinal and current research as well as building upon previous reviews, these articles closely examine preservice and inservice teacher preparation, instruction, and implementation of literacy instruction in the content-area class.
178

Magnetite deposits in the northern part of the Dore Lake complex, Chibougamau district, Quebec.

Dorr, André. January 1969 (has links)
No description available.
179

The origin of the Breton breccia, Batchawana Area, Ontario.

Blecha, Matthew. January 1968 (has links)
No description available.
180

Hydrogeology of three hard rock catchments in Britain

Bako, Mazadu Dader January 1988 (has links)
The ground water regimes of three small, undisturbed (natural) and accessible hard rock catchments representing the South, Midlands and the North of Great Britain have been hydrogeologically investigated and compared. There is a dearth of hydro geological information on hard rock areas in Britain. This is because the general availability of surface water and extensive sedimentary aquifers has not encouraged ground water prospecting in hard rock areas. In view of this, low flow study was considered essential since geology exerts a great influence on its characteristics. This was carried out using baseflow recession analysis. From a combination of practical, empirical and theoretical considerations aided by statistical analysis on a computer, baseflow recession constants which dynamically reflect the physiographic and geologic controls within a catchment were derived for the catchments investigated. These were used to characterise the behaviour of the low flows. A new method which is free of random selection of data for baseflow recession analysis is presented and a model for the curve fitting both by computer and manual methods are fully discussed and its application is also presented. Water balance computations for each of the three catchments is presented in chapter 2. Lithological units were identified by a detailed geological study. These were further investigated using resistivity and electromagnetic methods of geophysical survey. Hydrogeological properties of the aquifers were investigated by pumping test analysis and subsequent comparison of hydraulic conductivities from soils and baseflow studies. A water chemistry investigation of spring, river and rain waters has been carried out to try and defme flow paths of the ground water and this is presented in chapter 7. From these investigations, this research concludes that large community water supplies through boreholes can be economical only in one of the catchments (East Dart catchment). In the other two catchments (Blackbrook and Calder catchments), small community and household supplies are possible through boreholes (in some areas) and large diameter wells.

Page generated in 0.0603 seconds