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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.
111

An Exploratory study of Peng hu hight School Student¡¦s Place Attachment toward Centro Block in Magong.

How, Yow-rong 26 July 2007 (has links)
Penghu island is not only a unique and various ecological environment in the subsidiary , but also in it¡¦s culture.But these peculiar culture gradually disappearance because of urbanizing, and tourist prevailing. It was once the first street of Penghu, and had the important value and can¡¦t be replaced on the history and culture of Penghu, through development plan and then, the residential district's meaning to resident still exists. Can it¡¦s still called the first street of Penghu¡H Does the residents identification changed ? This research reviews and analyses the background which depends on the sense and collects the central street and is correlated with upgrading the transformation plan through documents, sketch the contours of resident's impression map of the central block to complement in questionnaire investigation way at the same time by way of interview, study the duty of high school of Penghu to grow to the sense of depending on of the central block, finds 1. It does not have too outstanding behavior to the sense of depending on of the central block. 2.High school students are not frequently aontacting contacting central street and many are affected by other people's experience or their own interests. 3.It¡¦s the block with historical significance. 4.Have special view and have history. 5.The attachement of centro block is not obvious different on psychology and behavior ,and their depend behavior is not obvious. 6. The identification sense of Psychological to the central block is more obvious. 7. It does not have obvious difference to the degree of attachement on the central block of the high school students of different backgrounds .8.The activity experience that the high school grows will influence the degree of attachement to the centrao block. 9.The image of centro block and the attitude of historyical rebuild will influence their attachement to centro block. These results can be offered to planner and administrator, conform with the environment which uses the demand in order to set up more comfortable environment while making the public affairs policy.
112

Toughening of Epoxies Based on Self-Assembly of Nano-Sized Amphiphilic Block Copolymer Micelles

Liu, Jia 16 January 2010 (has links)
As a part of a larger effort towards the fundamental understanding of mechanical behaviors of polymers toughened by nanoparticles, this dissertation focuses on the structure-property relationship of epoxies modified with nano-sized poly(ethylene-altpropylene)- b-poly(ethylene oxide) (PEP-PEO) block copolymer (BCP) micelle particles. The amphiphilic BCP toughener was incorporated into a liquid epoxy resin and selfassembled into well-dispersed 15 nm spherical micelle particles. The nano-sized BCP, at 5 wt% loading, can significantly improve the fracture toughness of epoxy (ca. 180% improvement) without reducing modulus at room temperature and exhibits only a slight drop (ca. 5 �C) in glass transition temperature (Tg). The toughening mechanisms were found to be BCP micelle nanoparticle cavitation, followed by matrix shear banding, which mainly accounted for the observed remarkable toughening effect. The unexpected ?nano-cavitation? phenomenon cannot be predicted by existing physical models. The plausible causes for the observed nano-scale cavitation and other mechanical behaviors may include the unique structural characteristics of BCP micelles and the influence from the surrounding epoxy network, which is significantly modified by the epoxy-miscible PEO block. Other mechanisms, such as crack tip blunting, may also play a role in the toughening. Structure-property relationships of this nano-domain modified polymer are discussed. In addition, other important factors, such as strain rate dependence and matrix crosslink density effect on toughening, have been investigated. This BCP toughening approach and conventional rubber toughening techniques are compared. Insights on the decoupling of modulus, toughness, and Tg for designing high performance thermosetting materials with desirable physical and mechanical properties are discussed.
113

An automatic optimization mechanism of circuit block partition for Fine-grain Multi-context Reconfigurable Process Unit

Chen, Jau-You 26 July 2006 (has links)
Due to the rapid development of today¡¦s multimedia communication systems, the complexity and scale of the systems increase day after day. For real-time computing of the systems which become more and more complicated, not only can we use VLSI chips, with the growth of manufacturing techniques of Integrated Circuit, we can apply the Reconfigurable Process Unit to improve real-time computing. Reconfigurable Process Unit is characterized by less cost in research and production as well as less time spent in research and development. Simultaneously, it processes more flexibility than VLSI chips and more suitability in taking advantageous position of real-time computing on an unspecified multimedia communication system. Fine-grain Multi-context Reconfigurable Process Unit has a mechanism of multi-context; therefore, it will take less time when the system reconfigures. This thesis deals with system environment of Computer-Aided Design under the structure of FMRPU, focusing on the placement and routing based on block partition method and designing an automatic optimization mechanism in accordance with historical records to elevate the rate of routable circuit. With the spirit from various existing algorithm of circuit, we add the factors of block partition, which forms the implements of placement and routing based on block partition. Combined clustering and the limit caused by the hardware structure of FMRRPU, we can have an accurate block partition on FMRPU. Through the continual increase of historical records, the assessment for the upper limit of the argument of routable circuit will get closer to the actual figure. Simultaneously, after the Logic Block Partition, the probability of routable circuit will get great assurance, and the time consumed in lots of repetitious computing on un-routable circuit will decrease. The experimental result reveals that the modified placement cost function can obtain enormous improvement under the comparison with that mentioned the master thesis of Tzu-che Huang. Not only the routability steps up, the unnecessary consumption also reduces largely. In routing, the negotiated congestion-delay algorithm produced on the basis of the transformation of maze routing algorithm has great suitability in the operation on FMRPU, which has many optimization goals and limited routing resource. After the redefinition of the cost function and expenditure for routing, we can operate with accuracy and the time spent on the delayed circuit will decrease.
114

Simulation of bilinear flow in single matrix block drainage

Branajaya, Romi Triaji 17 February 2005 (has links)
This thesis presents modeling of bilinear flow in tight gas wells and its behavior on single matrix block drainage. The objectives of this research are to: simulate a tight gas well using matrix block drainage under constant production pwf and with a constant production rate; be able to predict the behavior of matrix block drainage; study the effect of natural fracture(s) near a well; examine the matrix block drainage in a natural fracture network; and to validate a matrix block drainage model with a hydraulic fracture analytical solution. Two different production scenarios, constant pwf and constant rate, are assigned to a tight gas well in matrix block drainage. Matrix block drainage has two distinct permeabilities; a low permeability matrix serves as the tight gas reservoir with a high permeability streak surrounding the matrix. A well only produces from the high permeability fracture. Models were run with different sensitivity cases toward fracture half length, xf, and fracture permeability kf,. The fracture half-length reflects on a/b aspect ratio. The analytical solution for hydraulic fracture developed by Cinco-Ley and Guppy serves as the validation of matrix block drainage. Analysis on the flow regimes which occurred for different geometries and properties are provided. The log-log diagnostic plot of pseudo-pressure drop/gas rates and the log-log plot of dimensionless pressure derivatives and dimensionless reciprocal production rates are presented. Finally, an attempt to normalize the late time and early time of all geometries and properties is presented to obtain one analytical solution.
115

New federalism at work? : the case of the alcohol and drug abuse block grant and substance abuse spending in the American states /

Sim, Shao-chee, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 203-215). Available also in a digital version from Dissertation Abstracts.
116

Blends of a polystyrene-block-poly(ethylene oxide) copolymer and its corresponding homopolymers at the air-water interface

Bernard, Sophie. January 2006 (has links)
Thesis (M.S.)--University of Florida, 2006. / Title from title page of source document. Document formatted into pages; contains 61 pages. Includes vita. Includes bibliographical references.
117

Family and Consumer educators' opinions and attitudes toward block scheduling

Wehmeier, Jenny M. January 2003 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2003. / Includes bibliographical references.
118

Versatile chemistry for designer polymeric nanomaterials : synthesis and characterization of self-assembled montmorillonite-block copolymer composites

Easley, Jeffrey Alan 24 April 2013 (has links)
Self-assembled polymer nanocomposites are a promising class of advanced materials with unique structures and tunable properties. Control over the spatial arrangement and ordering of the constituent material is essential to developing composites with defined morphologies and properties. Here I report the synthesis of poly(n-butyl acrylate-b-styrene) from the surface of functionalized montmorillonite clay (MMT) via activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP). The application of ARGET ATRP to MMT surface-initiated polymerizations results in a robust and reproducible method for synthesizing well-defined tethered block copolymers. The chosen block copolymer architecture of the composite materials resembles that of a thermoplastic elastomer, with glassy PS domains sandwiching the rubbery PnBA domain, which is divided by the clay platelets. The structure was characterized by several techniques that examine the self-assembly and degree of clay exfoliation. Preliminary analysis of the material properties indicates elastomeric behavior. / text
119

Atomic block formation for explicit data graph execution architectures

Maher, Bertrand Allen 13 December 2010 (has links)
Limits on power consumption, complexity, and on-chip latency have focused computer architects on power-efficient designs that exploit parallelism. One approach divides programs into atomic blocks of operations that execute semi-independently, which efficiently creates a large window of potentially concurrent operations. This dissertation studies the intertwined roles of the compiler, architecture, and microarchitecture in achieving efficiency and high performance with a block-atomic architecture. For such an architecture to achieve high performance the compiler must form blocks effectively. The compiler must create large blocks of instructions to amortize the per-block overhead, but control flow and content restrictions limit the compiler's options. Block formation should consider factors such of frequency of execution, block size such as selecting control-flow paths that are frequently executed, and exploiting locality of computations to reduce communication overheads. This dissertation determines what characteristics of programs influence block formation and proposes techniques to generate effective blocks. The first contribution is a method for solving phase-ordering problems inherent to block formation, mitigating the tension between block-enlarging optimizations---if-conversion, tail duplication, loop unrolling, and loop peeling---as well as scalar optimizations. Given these optimizations, analysis shows that the remaining obstacles to creating larger blocks are inherent in the control flow structure of applications, and furthermore that any fixed block size entails a sizable amount of wasted space. To eliminate this overhead, this dissertation proposes an architectural implementation of variable-size blocks that allow the compiler to dramatically improve block efficiency. We use these mechanisms to develop policies for block formation that achieve high performance on a range of applications and processor configurations. We find that the best policies differ significantly depending on the number of participating cores. Using machine learning, we discover generalized policies for particular hardware configurations and find that the best policy varies significantly between applications and based on the number of parallel resources available in the microarchitecture. These results show that effective and efficient block-atomic execution is possible when the compiler and microarchitecture are designed cooperatively. / text
120

Phase separation in poly (styrene-b-ethylene oxide) thin films on different substrates

To, Chin-nang, Titan., 杜展能. January 2003 (has links)
published_or_final_version / abstract / toc / Physics / Master / Master of Philosophy

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