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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.
351

The early stage reaction on the Ag/Sn interfaces

Chin, Pei-ju 14 July 2010 (has links)
none
352

Study of Compound Gauss-Markov Image Field

Lin, Chi-Shing 04 September 2004 (has links)
In this thesis, we have a comprehensive study of the famous compound Gauss-Markov image model. In this model, a pixel in the image random field is determined by the surrounding pixels according to a predetermined line field. This model is useful in image restoration by applying two steps iteratively: restoring the line field by the assumed image field and restoring the image field by the just computed line field. CGM (Compound Gauss-Markov) image modeling is characterized by the line fields and the generating noise. In this thesis we apply combinations of techniques such as changing processing order, immediate updating, probability determination and different methods to find the best modeling. Furthermore, the effects of the above modeling are demonstrated by its energy, visual quality, and error resistance. Finally, by solving a set of nonlinear equations we apply the CGM model to an image restoration problem for image corrupted by a dusted lens.
353

A Study of the Key Success Factors for the Refurbishment of the Military Dependence¡¦s Residential Compound-Application of Analytic Hierarchy Process Method

Shyu, Ming-Der 29 August 2005 (has links)
There are many factors that effect the refurbishment of the military dependence¡¦s residential compound is sccceed or not.The government, in order to make policy and project which the refurbishment can be pursued and finished smoothly, reaching the goal of the refurbishment , it makes the government and occupant reach win-win, no matter from fund respect of the funds , project planning and carrying out the track , doing in the test amount and function of military dependence¡¦s residential compound ,etc.,they must carry on the multidimension degree , doing in the test amount faced more , it is to influence military dependence¡¦s residential compound to refurbish the most important key of the success or failure which factor is understood. And plan the unit , area to carry out management unit ,which in charge of construction of the project and family dependent's family etc. in the policy, each link be able to cooperate and support each other. This research is expected, consult the key success factor of the that Leidecker and Bruno puts forward and confirm the method , and this study uses the analytic hierarchy process , is it familiar with the military dependence¡¦s residential compound domain expert to refurbish topic to consult, including policy plan , carry out, at all levels personnel and the military dependence¡¦s residential compound households of representative , autonomy of unit in charge of construction know cadre , get in touch with people ,etc., promote difficulty and gains of experience meeting in the course to understand and study carefully to the thing that the family dependent corrects homework or papers, analyse via the interview real example of the questionnaire , gather together the view exactly familiar the refurbishment relevant personnel and domain expert, establish their influence the weight to extract to sum up. From the planing unit , area and carry out a representative of management unit , unit in charge of construction of the project and regional military dependence¡¦s residential compound and carry on the analysis of the questionnaire to the policy of general headquarters finally, by constructing the views of the domain expert and responsible person differently, consider 3 literary composition surface, it is the most important the funds fund, and the factor by seeming to succeed in five indispensable keys wholly, management , financial raising money , funds of changing the special budget for the military dependence¡¦s residential compound respectively are compiled and editted, the price influence the will of living and include in the development plan of the city .
354

Developing Electrospray-Assisted Pyrolysis Ionization/Mass Spectrometry for Rapid Characterization of Trace Polar Components in Macromolecules

Hsu, Hsiu-Jung 24 July 2006 (has links)
ABSTRACT In this paper we describe the use of electrospray-assisted pyrolysis ionization/mass spectrometry (ESA-Py/MS) to selectively ionize trace polar compounds that coexist with large amounts of nonpolar hydrocarbons in synthetic polymer, crude oil, amber, humic substances, and rubber. Samples of different origins are distinguished rapidly by their ESA-Py mass spectra without prior separation or chemical pretreatment. During ESA-Py analysis, the samples in their solid or liquid states were pyrolyzed at 590 ¢XC using a commercial Curie-point pyrolytical probe; the gaseous pyrolysates were transferred into a glass reaction cell; the polar compounds (M) in the pyrolysates were then ionized in the form of protonated molecules (MH+), through their reactions with the charged species in the ESI plum. Although the major components of the pyrolysates are nonpolar hydrocarbons, their lack of functional groups that can receive a proton in the ESA-Py source results in no hydrocarbon ion signals being produced; thus, the ions detected in ESA-Py mass spectra all result from trace polar component in the pyrolysates.
355

Investigation on Gauss-Markov Image Modeling

You, Jhih-siang 30 August 2006 (has links)
Image modeling is a foundation for many image processing applications. The compound Gauss-Markov (CGM) image model has been proven useful in picture restoration for natural images. In contrast, other Markov Random Fields (MRF) such as Gaussian MRF models are specialized on segmentation for texture image. The CGM image is restored in two steps iteratively: restoring the line field by the assumed image field and restoring the image field by the just computed line field. The line fields are most important for a successful CGM modeling. A convincing line fields should be fair on both fields: horizontal and vertical lines. The working order and update occasions have great effects on the results of line fields in iterative computation procedures. The above two techniques are the basic for our research in finding the best modeling for CGM. Besides, we impose an extra condition for a line to exist to compensate the bias of line fields. This condition is based upon a requirement of a brightness contrast on the line field. Our best modeling is verified by the effect of image restoration in visual quality and numerical values for natural images. Furthermore, an artificial image generated by CGM is tested to prove that our best modeling is correct.
356

Ultra-fine grain two-phase aluminum alloys produced by friction stir processing

Hsu, Chih-jing 22 January 2007 (has links)
Friction stir processing (FSP) is applied to produce particulate-reinforced aluminum matrix composites with ultrafine grained structure from elemental powder mixtures of Al-Cu, Al-Ti and Al-Si. The microstructures of the composites were characterized by the use of XRD, SEM and TEM. Microhardness, tensile and compressive tests were performed to evaluate the mechanical properties of these composites. The mechanisms of microstructure evolution in FSP and the strengthening mechanisms in these composites are discussed. In the Al-Si system, the Si particles were broken and uniformly distributed in the stir zone by the application of multiples-pass FSP. The average size of Si particles and Al grains were refined to below ~2
357

The Relationship of Sn Whisker Growth and Sn-plating Process

Lu, Min-hsien 29 June 2007 (has links)
New environmental regulations enforce the electronic industry to replace Pb-Sn solder due to Pb could contaminate our environment. Pure Sn has good material properties such as solderability, conductivity and anti-corrosion. Pure Sn is a good candidate to replace Pb-Sn solder. One of the disadvantages of pure Sn is the whisker growth phenomenon. Whisker problem has become a major concern in electronic industry due to the trend toward component miniaturization and pitch reduction. It is well understood that the root cause for tin whisker growth is the compressive stress within the tin layer. In the literature, the main stress sources are, (1) the intermetallic layer induced interface stress, (2) the difference of thermal expansion coefficient between Sn layer and substrate and (3) the mechanical residual stress from trim-form operation after tin plating. In our study, we used the electrochemical electrolysis method and Cross-section Polisher (CP) to examine the tin whisker growth mechanism. In the result, we can clearly show the Cu6Sn5 phase grow up in the tin grain boundary regions and demonstrate that the Cu6Sn5 phase formation is the main cause of the tin whisker growth. We also discuss the relationship of tin whisker growth and tin-plating process parameters that include the temperature effect; Ni underlay effect and tin-plating bath effect. For the temperature effect, the Cu6Sn5 is the major phase at 150¢XC aging. The mechanism behind its growth mechanism was grain boundary diffusion at the earlier stage and then the bulk diffusion in the later stage. The application of 150¢XC post-heat treatment could drive the bulk diffusion and form a layer type Cu6Sn5 phase to eliminate the whisker growth. For the Ni underlay effect, the Ni underlay can block the Cu atom diffusion to the tin layer and changed the tin layer stress state from compressive to tensile. Therefore, the tin whisker can be eliminated. For the tin-plating bath effect, in the sulfuric acid base and uses Triton X-100 as the surface active agent, may transform the whisker type to particular tin grain type. Thus, this tin-plating solution can restrain the tin whisker growth.
358

Multi-resolution Visualization Of Large Scale Protein Networks Enriched With Gene Ontology Annotations

Yasar, Sevgi 01 September 2009 (has links) (PDF)
Genome scale protein-protein interactions (PPIs) are interpreted as networks or graphs with thousands of nodes from the perspective of computer science. PPI networks represent various types of possible interactions among proteins or genes of a genome. PPI data is vital in protein function prediction since functions of the cells are performed by groups of proteins interacting with each other and main complexes of the cell are made of proteins interacting with each other. Recent increase in protein interaction prediction techniques have made great amount of protein-protein interaction data available for genomes. As a consequence, a systematic visualization and analysis technique has become crucial. To the best of our knowledge, no PPI visualization tool consider multi-resolution viewing of PPI network. In this thesis, we implemented a new approach for PPI network visualization which supports multi-resolution viewing of compound graphs. We construct compound nodes and label them by using gene set enrichment methods based on Gene Ontology annotations. This thesis further suggests new methods for PPI network visualization.
359

Morphological Priming In Turkish Nominal Compound Processing

Ozer, Sibel 01 September 2010 (has links) (PDF)
Compounding, constructing new words out of previously known words by means of simple concatenation mostly, can be counted as one of the major word production mechanisms in the majority of languages. Their importance in the history of human languages warrants a detailed study with respect to the language faculty and related cognitive aspects. In the last decade, compound production as well as comprehension have become highly debated and investigated areas of research. Morphological priming is one frequently employed paradigm for the investigation of compounding. Whether morphologically complex words undergo a decomposition-composition process, respectively, during comprehension and production or whether they are all listed in full form in the lexicon is one key question hitherto addressed in several studies related to English, German, Dutch and Chinese nominal compound words. The present study is concerned with compound production in Turkish. Various types of Turkish compounds were investigated ((i) bare JCs (
360

Determination Of Thallium By Volatile Compound Generation Atomic Absorption Spectrometry

Ataman, Seval 01 October 2011 (has links) (PDF)
Determination of thallium is important due to its toxic effects on the environment and human health. Extremely low abundance of thallium in earth crust requires very sensitive and accurate methods for determination of this element. Although volatile compound generation is a sensitive, fast and economical method, thallium determination by this method has not been sufficiently investigated in literature, because of the fact that the formation of volatile forms of this element is a difficult task. A continuous flow volatile compound generation system was developed and parameters that affect the analytical signal were optimized. Sample solutions were acidified with 0.5 mol/L HNO3 and prepared in 0.0005% (v/v) rhodamine B and 1.0 mg/L Pd while 0.5% (m/v) NaBH4 stabilized in 0.5% (m/v) NaOH was used as reductant. Fast decomposition and unstability of thallium volatile species affected system performance negatively. Flow injection volatile compound generation studies were carried out with a special system. After optimizations, LOD and LOQ values were calculated as 12 ng/mL and 40 ng/mL according to peak height values in HNO3 medium. Similarly, in HCl medium LOD and LOQ values were calculated as 14 ng/mL and 45 ng/mL. Addition of Te and Pd to the sample solution containing co-enhancement reagent rhodamine B improved volatile compound generation efficiency in peak height by 3.6 and 9.3, respectively. Type of the acid used was affected peak heights and peak shapes of Tl+ and Tl3+ volatile species and HNO3 medium gave better results. By changing the location of introduction for Ar gas, the sources of memory effects and reasons of peak broadening were investigated. Most of the memory effects were coming from the gas-liquid separator (GLS) or before the GLS, as well as T-tube atomizer. Nature and behavior of Tl volatile species were also investigated and it was found that Tl and also Pd were generated in the form of nanoparticles. Transmission electron microscopic (TEM) measurements prove the presence of Tl nanoparticles in the analyte species transported to the atomizer by the effect of carrier Ar gas.

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