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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

"J2EE vs Microsoft.NET"A Comparison of two platforms for component-baseddevelopment of web applicationsDeveloper’s point of view

Iqbal, Asad, Ullah, Naeem January 2011 (has links)
Paper is interested for anyone such as software developers,students, designers and companies who want to choose bestplatform.Paper provides powerful comparison between .NET webapplication using ASP.NET and Java application using JSFtechnology for component based development. The choice ofsuitable platform for future is not easy, both has its strength andweaknesses. Web applications implemented within specifiedrequirements using component technology such as EJB and ClassLibrary. This application helps to compare both platforms againsteach other and provide support to target audience to takedecision while choosing platform. Although both .NET and J2EEhave covers a great deal of platform fields, paper will especiallyfocus on components, programming languages, tools andtechnologies. At the end, we discussed our point of view whileworking on both applications using component and providewhich platform is easier and user friendly for target audience.
212

HELPING COGNITIVE RADIO IN THE SEARCH FOR FREE SPACE

Gonzales Fuentes, Lee January 2012 (has links)
Spectrum sensing is an essential pre-processing step of cognitive radio technology for dynamic radio spectrum management. One of the main functions of Cognitive radios is to detect the unused spectrum and share it without harmful interference with other users. The detection of signal components present within a determined frequency band is an important requirement of any sensing technique. Most methods are restricted to the detection of the spectral lines. However, these methods may not comply with the needs imposed by practical applications.  This master thesis work presents a novel method to detect significant spectral components in measured non-flat spectra by classifying them in two groups: signal and noise frequency lines. The algorithm based on Fisher’s discriminant analysis, aside from the detection of spectral lines, estimates the magnitude of the spectral lines and provides a measure of the quality of classification to determine if a spectral line was incorrectly classified. Furthermore, the frequency lines with higher probability of misclassification are regrouped and the validation process recomputed, which results in lower probabilities of misclassification. The proposed automatic detection algorithm requires no user interaction since any prior knowledge about the measured signal and the noise power is needed. The presence or absence of a signal regardless of the shape of the spectrum can be detected. Hence, this method becomes a strong basis for high-quality operation mode of cognitive radios. Simulation and measurement results prove the advantages of the presented technique. The performance of the technique is evaluated for different signal-to-noise ratios (SNR) ranging from 0 to -21dB as required by the IEEE standard for smart radios. The method is compared with previous signal detection methods.
213

Identification of cause of impairment in spiral drawings, using non-stationary feature extraction approach

Yaseen, Muhammad Usman January 2012 (has links)
Parkinson’s disease is a clinical syndrome manifesting with slowness and instability. As it is a progressive disease with varying symptoms, repeated assessments are necessary to determine the outcome of treatment changes in the patient. In the recent past, a computer-based method was developed to rate impairment in spiral drawings. The downside of this method is that it cannot separate the bradykinetic and dyskinetic spiral drawings. This work intends to construct the computer method which can overcome this weakness by using the Hilbert-Huang Transform (HHT) of tangential velocity. The work is done under supervised learning, so a target class is used which is acquired from a neurologist using a web interface. After reducing the dimension of HHT features by using PCA, classification is performed. C4.5 classifier is used to perform the classification. Results of the classification are close to random guessing which shows that the computer method is unsuccessful in assessing the cause of drawing impairment in spirals when evaluated against human ratings. One promising reason is that there is no difference between the two classes of spiral drawings. Displaying patients self ratings along with the spirals in the web application is another possible reason for this, as the neurologist may have relied too much on this in his own ratings.
214

Calibration Based On Principal Components

Kassaye, Meseret Haile, Demir, Yigit January 2012 (has links)
This study is concerned in reducing high dimensionality problem of auxiliary variables in the calibration estimation with the presence of nonresponse. The calibration estimation is a weighting method assists to compensate for the nonresponse in the survey analysis. Calibration estimation using principal components (PCs) is new idea in the literatures. Principal component analysis (PCA) is used in reduction dimension of the auxiliary variables. PCA in calibration estimation is presented as an alternative method for choosing the auxiliary variables. In this study, simulation on the real data is used and nonresponse mechanism is applied on the sampled data. The calibration estimator is compared using different criteria such as varying the nonresponse rate and increasing the sample size. From the results, although the calibration estimation based on the principal components have reasonable outputs to use instead of the whole auxiliary variables for the means, the variance is very large compared with based on original auxiliary variables. Finally, we identified the principal component analysis is not efficient in the reduction of high dimensionality problem of auxiliary variables in the calibration estimation for large sample sizes.
215

A study on the Revealed Patent Advantage and the R&D productivity of IC Design companies

Chou, Cheng-chieh 23 July 2010 (has links)
The Strategies of the firms in Patent are not only about the future, but also forming the barrier for competitor. For the sake, we should develop the patent strategies and technological position.This study goes to the discussion of technological position by the patent multivariate analysis, and suggest the patent strategy by the difference within and between the groups which were clustered from IC design companies. This study selects twenty gobal IC design companies,which are always on the top25 of the industry.In case1 ,we wonder figure out the technological postion and the path of technology shift.In case2,we can recognize the technological position as industrial position. In case 1, we got four clusters by cluster analysis.Cluster 1 is called SpecialistII,and cluster2 is called Strong Generalist, and cluster 3 is called Specialist I,and cluster 4 is called Weak Generalist. For further observation, the firms with technology shift will shift from cluster 1 to cluster 2 in the same direction.Others still maintain the same strategies in their clusters. In case 2 , we also got four clusters by the analysis. Cluster 1 is called Weak Generalist ,and cluster 2 is called Strong Generalist, and cluster 3 is called Specialist I,and cluster 4 is called Specialist III.As financial results , we got homogeneity within a cluster except cluster 4. Performance between clusters, we made and observed the line chart of trend in the selected financial ratio and we used the median of samples within a cluster. In case 2,it seems heterogeneous in ROA and Price-to-book ratio in the chart.In case1,it is also heterogeneous in ROA and price-to-book ratio.It¡¦s significant and positively correlated in R&D productivity(GrossMargin-to-R&D ratio) between others by the correlation coefficient matrix.It seems to be the proxy to the other financial ratio.
216

Product or Cause? Influences of Donation Magnitude and Consumer Mood

Yang, Chia-yen 12 August 2010 (has links)
Cause-Related Marketing(CRM), which was initiated by American Express Company in 1981 to support the arts in San Francisco raising fund. Many academic researches have tried to discover the benefit and risk of CRM since 1990s. Print advertisement is a main channel for CRM. Therefore, how to structure CRM ads, especially for the focus of visual component, will be important in CRM campaigns. Based on previous studies relevant to charitable donations, this study compares the effects of cause-focused and product-focused CRM ads through experimental design method. In addition, donation magnitude and consumer mood are also considered to observe how they sway the effectiveness of CRM ads. The present study employs an experimental design to investigate the effects of the types of visual component (cause-focused vs. product-focused), donation magnitude (5% of invoice price vs. 20% of invoice price) and consumer mood (positive vs. negative) on CRM effectiveness. A 2x2x2 factorial design is conducted. Eight different scenarios are established and the ad effects are measured by purchase intention and attitude toward the brand. The results indicate that the cause-focused ads are more effective than the product-focused ads. Although donation magnitude does not make a difference in a cause-focused ad, but low donation magnitude leads to higher purchase intention when a product-focused ad is presented. Positive mood facilitates the advertising effects of cause-focused ads. Finally, low donation magnitude and positive mood enhance the advertising effects of product-focused ads. The implications of these findings are discussed as well as the limitations and directions for future research.
217

A Methodology of PIM Modeling for SOA

Chang, Yu-Tzu 03 July 2011 (has links)
¡@¡@With the rapid advance of information technology, Service Oriented Architecture (SOA) is becoming a mature technology. Many software firms have implemented it to enhance the flexibility and efficiency of system development. Several systems analysis and design methods have been proposed to develop the SOA systems. Among them, however, the detailed guideline and procedure for identifying the services and components in PIM (Platform Independent Model) stage are lacking. ¡@¡@To alleviate the forgoing problem, this study proposed a PIM modeling methodology for developing an SOA system. The methodology which includes the business process, service, and component layers, uses the unified modeling language to describe the detailed modeling processes and rules for each layer. The research methodology is articulated using the design science research methodology. A usability evaluation is performed to demonstrate its applicability with a testing case. With this proposed method, the system developer can easily model the PIM of SOA systems, and thereby enhance the efficiency and effectiveness of system development.
218

Numerical simulation of small power supply in natural convection environment

Chao, Tzu-Chuan 07 February 2012 (has links)
The power supply for electronic devises is demanded to be lighter and smaller in nowadays market. Therefore, the cooling problem becomes the major design challenge due to reduced heat transfer area. In this thesis, a numerical computation method is employed to numerically simulate the natural convection heat transfer field for a small power supply placed on the ground or table in atmospheric conditions. The effects of parameters are studied including internal heat sink structure, shell structure, heat rate of generation, body size and ground material. The results of the present study can provide design reference.
219

A methodology for component-based user interface modeling with UML

Cheng, Chih-Hsiung 12 July 2004 (has links)
User interface (UI) has become the key element of modern information systems (ISs) and is commonly viewed as one of the decisive factors for the success of an IS project. Many component-based development tools have been introduced by software vendors to meet the needs of designing a variety of UIs. Such modern design tools offer system developer vehicles to create sophisticated UIs with a few codes. However, the modeling methodology from the stages of user requirement modeling to UI modeling based on the modern design tools is virtually lacking. This study presents an integrated modeling methodology, which integrates the unified modeling language with interface drawing and interface glossary to provide a seamless and graphical approach and specifications for component-based UI modeling from user requirement modeling. A real-world case using the integrated approach is presented and a prototype system is developed to illustrate the concepts, application, and the advantages of using the proposed methodology.
220

The relationships between ozone concentration and meterrological parameters in the urban area, Kaohsiung

Liao, Siou-yi 16 June 2005 (has links)
ABSTRACT The relationships between high ozone events and synoptic weather patterns were investigated based on the meteorological and air-quality data at four monitoring stations in Kaohsiung city during 1997 to 2004 in this study. The PCA (principal component analysis) and correlation studies show that ozone concentration exhibit positive correlations with the ambient temperature and sunshine duration, while negative correlation with the cloud cover. The frequency of high ozone events was highest under the weather patterns of northeast seasonal wind (B1 type), high-pressure system with recirculation (B3 type), high-pressure system with offshore type (B2 type), and in the warm core of approaching front (B4 type), most frequently in autumn, winter, and spring, and least frequently in summer. The above four weather patterns are primarily dominated by the high-pressure system from Mainland China, with relatively cold and dry weather and little rain in Taiwan. Since the high-pressure center is usually located north or northeast of Taiwan during autumn, winter, and spring such that the leeside areas of Central Mountain Ranges in the western coast of Taiwan are prone to high pollution events, particularly when the wind speed is low (< 4m/s) and duration of sunshine is long (> 5.5 hr). Or sometimes the meso-scale wind system, for example, the sea-land breeze or the combined flow caused by the detouring flow from the Henchun Peninsula and northeast wind tends to raise the pollutant concentrations. Keywords¡GHigh ozone event, Synoptic weather pattern, Principal component analysis.

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