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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.
441

Study and Implementation of a Web GIS with Flash

li, Hsin-cheng 20 January 2011 (has links)
Google announced Google Maps Service on June 2005, and they developed and used many technologies to solve performance balance issue that long existing in client-server GIS system, including Ajax, map data pre-processing, and browser's cookies system. OGC defined this mechanism as WMS-C. However, Ajax is a technology based on HTML and javascript, when processing mass spatial data, it could be the bottleneck of performace. Therefore, using browser plugin to improve performance on data processing is necessary. This paper discuss on WebGIS related technologies, including CGI, Java Applet, Ajax, Flash, and compare their weakness and strength, then we focus on analyzing Java Applet, Ajax, Flash. Flash provides better graphics processing abilities, smooth interactive operation, fast display performance, make it suitable to be a WebGIS platform. Flash also support multi-platform and multi-browser, and it can be deployed with the same programming code. So this study chooses Flash and it's language Action Script to develop WebGIS client, backend with Mapserver to publish map data. We also use TileCache to pre-process aerial images of National Sun Yat-sen University into image tiles. Also it is overlaid with Kaohsung district map as vector data. The actionscript in the WebGIS core library include classes like Map, View, Layer, TMSLayer, FeatureLayer. It is fully implemented as a Flash based WebGIS system. Lastly, we compare the Flash-based MapServer system with MapServer only regarding to there performance and interactivity. On loading vector data, flash performance is nearly equal to Mapserver. When vector panned, flash performs better because flash uses pre-loading image tiles, but Mapserver renders repeatly after every move. On interactivity, flash can directly zoom the map with mouse wheel, and it can shorten user¡¦s operating time. And flash can also dispaly animations like fade in, out, etc. After removing one single layer, the map still preserve the other layers, so users can handle the map information more precisely, and can reduce the loading of servers.
442

An Action Research Study on Mind Mapping in Chinese Language Teaching and Learning of Sixth Grade Students in an Elementary School

Yi, Tsu-Chen 06 July 2012 (has links)
¡@¡@This action study aimed to investigate the process and impact of the use of mind mapping on Chinese language teaching and learning of sixth grade students. There were twenty-five students participated in this action research. The teacher/researcher constantly reviewed and modified teaching process to develop appropriate learning models during two cycles of action research. Data were collected from pre and post reading comprehension tests, reflection notes, video recordings, interviews, questionnaires, learning sheets and students¡¦ assignments of mind mapping. ¡@¡@The findings were as follows¡G 1. Mind mapping used in Chinese language teaching could improve reading comprehension based on the results of pre and post reading comprehension tests. 2. Based on students¡¦ prior knowledge, the teacher/researcher used fill-in content types mind mapping, structure models, reading materials and vocabularies, thus teaching has the best effect on students. 3. In the beginning stage, students just focused on the aspect of drawing skill of mind mapping. Later, they learned to focus on how to catch the main idea of the article. Most of students can emphasis on both skills in the end. In the process, most of students had positive attitudes toward mind mapping instruction, especially in the group mind mapping activity. 4. The teacher/researcher has promoted her own professional development through constant refelection and adjustment in her teaching practice. ¡@¡@Based on the findings mentioned, the researcher provdied some suggestions regarding practical teaching practice and recommendations for further research.
443

Fatty Acid Carcass Mapping

Turk, Stacey N. 14 January 2010 (has links)
We hypothesized that subcutaneous (s.c.) adipose tissue would differ in monounsaturated (MUFA) and saturated fatty acid (SFA) composition among different depots throughout a beef carcass. To test this, 50 carcasses from a variety of breed types and backgrounds were sampled. External fat samples were collected from eight different carcass locations: round, sirloin, loin, rib, chuck, brisket, plate and flank. Samples were used to provide information on slip points, fatty acid composition and MUFA:SFA ratios. Lipids were extracted from s.c. adipose tissue by a modified chloroform:methanol procedure, and fatty acid composition and slip points were measured. The brisket was significantly lower in palmitic (16:0) and stearic (18:0) acid than the other seven sampling sites (P = 0.001). The brisket demonstrated the highest values of MUFA (P = 0.001) with the exception of possessing the lowest value of transvaccenic (18:1t11) acid (P = 0.002). There were also significant differences in the amounts of PUFA among the eight sampling sites. The lowest values were from the brisket with a mean of 25.1. The flank had the highest slip point with a mean of 39.0 (P < or = 0.001). There was a high negative correlation shown between palmitoleic and stearic acid (R2 = 0.827). The brisket displayed the highest values for MUFA:SFA ratios (P = 0.001), whereas the flank was the lowest. Due to the significant differences amongst fat depots within bovine carcasses in their fatty acid composition we conclude that substantial differences exist across fat depots.
444

Defining the Molecular and Physiological Role of Leaf Cuticular Waxes in Reproductive Stage Heat Tolerane in Wheat

Mondal, Suchismita 2011 May 1900 (has links)
In wheat, cooler canopies have been associated with yield under high temperature stress. The objectives of this study were, i) to understand the role of leaf cuticular waxes as physiological adaptive mechanisms during reproductive stage high temperature stress ii) define quantitative trait loci (QTL) regulating leaf cuticular waxes and determine its link with the QTL for reproductive stage heat tolerance iii) define stable QTL associated with leaf cuticular waxes and yield stability across environments. For the first objective, thirteen wheat cultivars were subjected to a 2-day heat treatment at 38 degrees C at 10 days after pollination (DAP). Leaf cuticular waxes, canopy temperature depression and stomatal conductance were estimated during high temperature stress. At maturity the percent reduction in yield components in each cultivar was calculated. The wheat cultivars 'Kauz' and 'Halberd' had significantly high leaf cuticular wax content of 2.91mg/dm^-2 and 2.36mg/dm^-2 respectively and cooler canopies. Leaf cuticular waxes were significantly correlated with leaf temperature depression and reduction in yield components. A set of 121 recombinant inbred lines (RIL) population derived from the cross of heat tolerant wheat cultivar 'Halberd' and heat susceptible wheat cultivar 'Karl 92' was utilized for QTL mapping. The RIL population received a 2-day short-term high temperature stress at 38°C at 10DAP in 2008 and a long-term high temperature stress at 38 degrees C from 10DAP until maturity in 2009 in the greenhouse. The RIL population was also planted in College Station, Texas in 2009 and 2010 and in Uvalde, Texas in 2010. Leaf cuticular wax was estimated at 10DAP and leaf/spike temperatures were recorded during grain filling. Yield components were estimated after harvest. Heat susceptibility indexes for main spike yield components were estimated in the greenhouse. Overall ten significant QTL were identified for leaf cuticular waxes each explaining 8-19 percent of the variation respectively. Stable QTL for leaf cuticular waxes were located on chromosome 5A and 1B and co-localized with QTL for leaf/spike temperature depression and HSI for kernel weight and single kernel weight of main spike. Another QTL on chromosome 1B contributed by Karl92 was found in the greenhouse and field environments and co-localized with a previously identified QTL on 1B for spike non-glaucousness. The results suggest that leaf cuticular waxes may reduce leaf temperatures and improve adaptation during high temperature stress.
445

Low Power Mapping Methodology for Multi-voltage System

Xie, Yao-Ren 21 July 2006 (has links)
Since the development of SoC is very fast, how to reduce the power consumption of SoC has become a very important issue. To overcome the issue, the hardware circuit provides multi-voltage method to reduce task power consumption. On the other hand, the software tool decides the task voltage to minimize the total power consumption. In this thesis, we developed a genetic algorithm to solve the voltage mapping problem of multi-voltage systems. This goal of this genetic algorithm is to consider the time constraints or power constraints in the multi-voltage system to find the better solution. In order to apply genetic algorithm to solve voltage mapping problem, we build a compilation flow that embeds in the genetic algorithm. To demonstrate the efficiency of proposed approach, we apply compilation flow to two examples. One is multi-voltage reconfigurable processor system. The processor in the system provides multi-mode and multi-voltage. The multi-mode can reduce the execution time of tasks with high parallelism. Multi-voltage can reduce the power consumption of task by decreasing voltage. We use genetic algorithm to choose task mode to achieve the performance goal. Another is multiple multi-voltage processors. We use list-scheduling to find the task schedule and use genetic algorithm to choose the task voltage. This method can reduce total power consumption. According to the experimental results, the proposed genetic algorithm can reduce the power consumption efficiently.
446

Parameter Identification of ROV by Decoupled Dynamical Models with Projective Mapping Method

Chang, Hsu-Hui 23 August 2006 (has links)
Remotely operated vehicle (ROV) dynamics is affected by hydrodynamic forces such as added mass and viscous drag force. Both of added mass and drag force coefficients can be measured by a set of Planar Motion Mechanism (PMM) tests; however, it is costly. In this study, an economic method for identifying hydrodynamic parameters of ROV is given. A simplified nonlinear ROV dynamics model with twelve unknown hydrodynamic parameters in six degrees of freedom was derived for simulations. The identification is based on experimental data obtained by projective mapping method which is utilized to measure the planar motions of a ROV. Then least-squares optimization is performed by comparison between the theoretical simulations and the actual motion measurements. But, an optimization computation involving a large number of parameters is likely to get trapped in a local minimum. Therefore, to reduce the number of parameters to be optimized, some models of simple motions such as surge, sway, surge and sway, yaw, and heave are decoupled from the ROV dynamic model. A commercial ROV ¡§Seamor¡¨ that equipped with two vertical thrusters, two horizontal thrusters, and a depth sensor is used for identification. The experiments for measuring ROV motions of surge, sway, surge and sway, and yaw were performed in a swimming pool in National Sun Yat-sen University. A video camera is utilized to capture ROV for position estimation using projective mapping method. As for the heave motion of ROV, the experiment was conducted offshore the Shio-Liu-Qiu Island and the ROV depth was measured by an onboard pressure sensor. Then, optimal hydrodynamic parameters are identified in sequence of surge, heave, yaw, sway, and then surge and sway. Verification experiments were performed and the simulation results with the optimum values of hydrodynamic parameters show good agreement with the measured data from verification experiments.
447

Construction of an Ion Imaging Apparatus

Yu, Chih-Shian 29 July 2002 (has links)
Conventional ion imaging techniques utilized grid electrodes to extract and to accelerate ions toward the detector. The disadvantages of grid electrodes caused transmission reduction, severe image distortions and image blur due to the non-point source geometry. All these problems can be solved by the utilization of an open lens electrode assembly. In velocity mapping, the extracting electric field of an open electrostatic lens that projects the ion cloud onto the detector. The major advantage of the combination of ion lens optics and two-dimensional detection is that ions from different positions with the same initial velocity vector would be mapped onto the same position on the detector, which was named ¡§ velocity map imaging .¡¨ The kinetic energy resolutions achievable with this method are not generally considered as being competitive with the best photofragment translational spectroscopy technique. But Ashfold and co-workers have demonstrated that velocity imaging methods can provide dissociation energy with one wavenumber resolution, i.e., it compares favourably with all rival photofragment translational spectroscopy techniques. We construct an ion imaging apparatus and the pressure inside can be maintained at ~ 10-6 Torr with differential pumping when the pulsed nozzle is shut off. The pressure in the source chamber raises from 2.1¡Ñ10-6 to 1.0¡Ñ10-5 Torr and the pressure in the photolysis chamber raises from 2.4¡Ñ10-7 to 3.6¡Ñ10-7 Torr, when the pulsed nozzle is turned on with a stagnation pressure at 3 bar. Because reactive chemicals attack the piezo disk translator and ruin the Viton O-ring, a modified pulsed nozzle and Teflon O-ring are adopted to overcome these problems. This pulsed nozzle is mounted on a three-dimensional translational stage such that the nozzle can be aligned inside vacuum. The homogeneity of the accelerating electric field is crucial to the performance of the ion imaging apparatus. To meet this requirement, parallel electrodes of identical dimensions have been assured in the manufacture of the ion lens assembly.
448

Computational aspects of radiation hybrid mapping

Ivansson, Lars January 2000 (has links)
No description available.
449

Simulating vegetation shifts and carbon cycling in Yosemite National Park /

Conklin, David R. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 116-127). Also available on the World Wide Web.
450

Phenomenographic instructional design : case studies in geological mapping and materials science.

McCracken, Janet. January 2001 (has links)
Thesis (Ph. D.)--Open University. BLDSC no. DXN060929.

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