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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.
21

Pay determinants in the Malaysian economy : evidence from employee, employer, and employer-employee perspectives

Zulkifli, Normala January 2016 (has links)
The objective of the thesis is to investigate Malaysia’s pay determinants from three different perspectives, namely: employees’ perspective, employers’ perspective, and both employees-employers’ perspectives. As a matter of fact, previous studies have not been able to document the potential impact of employers and firms on pay determinants within the Malaysian economy, owing to a lack of appropriate data. Therefore, with the availability of new datasets – worker-level dataset (WLD) and firm-level dataset (FLD) obtained from the Second Malaysian Productivity Investment Climate Survey (PICS-2), we have developed a matched-worker-firm dataset (MWFD), so that by employing such dataset it will add a new dimension to pay analysis in Malaysia as well as allowing for a comprehensive understanding and clearer picture of Malaysia’s pay system. From the employees’ prospective, the findings of this thesis indicate that a worker with a higher education level, skills and training generally gets a higher pay compared to those without. In addition, a worker who undergoes training from his/her current employer gets a higher pay compared to those who had training from a previous employer or only off-the-job training. At the same time, workers with complex computer skills, as well as those who are in professional employment and management, also receive a considerably higher pay. From the employers’ prospective, however, the findings indicate that firm size, human capital stock in the firm, worker performance, capital stock, and firm performance are important factors that affect the Malaysian average monthly pay. Besides, the elasticity of pay with respect to employer size is two percent, and this figure supports the notion that the Malaysian labour market can be characterised as imperfect competition. From both employers-employees’ prospective, it is obvious that both observable worker characteristics and unobserved firm-effects are key elements of pay determinants. Nevertheless, firm effects seem to explain the variability in pay determinants more than observable worker characteristics. In addition, the relationship between pay component and firm performance exhibits a positive tendency. This implies that workers get a higher pay either because of worker characteristics or that firm-effects are being employed in firms that are more productive and profitability.
22

Absorbing Layers and Non-Reflecting Boundary Conditions for Wave Propagation Problems

Appelö, Daniel January 2005 (has links)
The presence of wave motion is the defining feature in many fields of application,such as electro-magnetics, seismics, acoustics, aerodynamics,oceanography and optics. In these fields, accurate numerical simulation of wave phenomena is important for the enhanced understanding of basic phenomenon, but also in design and development of various engineering applications. In general, numerical simulations must be confined to truncated domains, much smaller than the physical space were the wave phenomena takes place. To truncate the physical space, artificial boundaries, and corresponding boundary conditions, are introduced. There are four main classes of methods that can be used to truncate problems on unbounded or large domains: boundary integral methods, infinite element methods, non-reflecting boundary condition methods and absorbing layer methods. In this thesis, we consider different aspects of non-reflecting boundary conditions and absorbing layers. In paper I, we construct discretely non-reflecting boundary conditions for a high order centered finite difference scheme. This is done by separating the numerical solution into spurious and physical waves, using the discrete dispersion relation. In paper II-IV, we focus on the perfectly matched layer method, which is a particular absorbing layer method. An open issue is whether stable perfectly matched layers can be constructed for a general hyperbolic system. In paper II, we present a stable perfectly matched layer formulation for 2 x 2 symmetric hyperbolic systems in (2 + 1) dimensions. We also show how to choose the layer parameters as functions of the coefficient matrices to guarantee stability. In paper III, we construct a new perfectly matched layer for the simulation of elastic waves in an anisotropic media. We present theoretical and numerical results, showing that the stability properties of the present layer are better than previously suggested layers. In paper IV, we develop general tools for constructing PMLs for first order hyperbolic systems. We present a model with many parameters which is applicable to all hyperbolic systems, and which we prove is well-posed and perfectly matched. We also use an automatic method, derived in paper V, for analyzing the stability of the model and establishing energy inequalities. We illustrate our techniques with applications to Maxwell s equations, the linearized Euler equations, as well as arbitrary 2 x 2 systems in (2 + 1) dimensions. In paper V, we use the method of Sturm sequences for bounding the real parts of roots of polynomials, to construct an automatic method for checking Petrowsky well-posedness of a general Cauchy problem. We prove that this method can be adapted to automatically symmetrize any well-posed problem, producing an energy estimate involving only local quantities. / QC 20100830
23

Hur uppfattas Rolf och Britta? : en attitydstudie kring kommentarer på internet och dess koppling till genus / Attitudes towards Rolf and Britta : a gender study about comments on the Internet

Calleberg, Anna January 2012 (has links)
Denna uppsats är en attitydinriktad genusstudie med fokus på internetkommentarer. Det huvudsakliga syftet är att ta reda på om det finns skillnader i hur människor uppfattar en manlig kommentarsskribent jämfört med en kvinnlig och om dessa skillnader går att knyta till genus, samt om de överensstämmer med tidigare liknande forskning. Metod och material i undersökningen är enkäter inspirerade av matched guise-tekniken, som delats ut till 60 försökspersoner där hälften är män och hälften är kvinnor. I enkäten får försökspersonerna läsa två olika kommentarer där den ena är undertecknad en man och den andra en kvinna. Hypotesen för undersökningen är att tydliga skillnader i uppfattningar av den manliga skribenten jämfört med en kvinnliga ska synas, och därmed följa ett snarlikt mönster som tidigare undersökningar av samma slag. Resultatet visar emellertid att skribenternas kön knappt har någon betydelse för hur försökspersonerna uppfattar skribenterna. I stället syns skillnader i uppfattningar av skribenten beroende vilken kommentar hen har skrivit, samt i om det är en man eller kvinna som bedömer. / This bachelor thesis examines attitudes towards gender by focusing on comments on the internet. The main purpose is to see if there are any differences in attitudes towards a female writer on the internet versus a male writer on the internet, and if the differences are comparable to earlier similar research. The method and material of this study are surveys inspired by the matched guise technique. 60 informants answered the surveys, where 50 % are men and 50 % women. The survey is based on two comments from the internet, where one is signed by a man and one by a woman. The hypothesis of this study was that there would be differences in the attitudes, depending on the sex of the writer, following the same pattern as earlier studies of the same kind. However, the results showed that the attitudes to the writers varied, but not so much depending on the sex of the writer, but more depending on the comment one has written and depending on the sex of the informant.
24

Geoacoustic Parameters Inversion by Ship Noise in the ASIAEX-SCS Experiment

Kuo, Yao-Hsien 03 October 2005 (has links)
Sound propagation can be greatly affected by seabed, especially in shallow water, therefore by understanding the geoacoustic parameters of sea bottom can help to improve the performance of sonar systems. In this study, ship noise collected by the vertical line array (VLA) in South China Sea experiment of the Asian Seas International Acoustics Experiment (ASIAEX SCS) in 2001 was used as a sound source to invert the geoacoustic parameters. The nearest horizontal distance between VLA and the passing ship was estimated by beamforming the receiving sounds on the array, and this distance was used in the sound propagation modal. In the modal, two layers structure were assumed for the bottom, so the sound speed (C1) and density (£l1) of sediment layer, sound speed (C2 ) and density (£l2) of subbottom layer, and total absorption coefficient (£\) need to be inverted. Matched field processing is used to solve this inverse problem, and computing the minimum cost function between the measured and modeled sound field, the best matched bottom parameters are C1¡×1600 m/s¡BC2¡×1650 m/s¡B£l1=1.6 g/cm3¡B£l2=2.1 g/cm3¡B£\=0.6 dB/£f. These results were compared with chirp sonar survey in this area, and the agreement is satisfactory.
25

Analysis and Application of Nonuniform Grid in FDTD method

Lin, Ming-Cun 26 June 2000 (has links)
The finite-difference time-domain (FDTD) method has been widely and effectively used for analysis in many kinds of electromagnetic problems. Generally, the computational space can be divided into many lattices with rectangular; and the length on each of these meshs is equivalent in unitary aspect. In some of those problems, a greatly improved accuracy of the solution can be obtained if a finer discretization is used in specific regions of the computational space. There are limitations of the present form of uniform FDTD. It must increase the computational cost (memory and CPU time). Concerning the impression, we are trying to find more efficient ways of utilizing nonuniform grids. Coarser mesh for uncomplicated structure and finer mesh for complicated structure in nonuniform grids. However, this way can use in part of cutting area only. There are two edges connects the truncation of computational space. A similar scheme has been used with nonuniform FDTD method by a modification to the mesh scheme. The subcell method is a very general approach, capable of analyzing arbitrarily-shaped structures. In local area the mesh change from rectangular to irregular. Subgridding method is dissimilar to the both methods. Furthermore, the anisotropic PML to decrease the electromagnetic wave from nonuniform mesh of the computational space. It have replaced Mur¡¦s first-order absorbing boundary conditions and Berenger¡¦s PML for improving computationally efficient. Finally, compare them with the anisotropic PML in the essay.
26

Aspects of matching and power in group randomized trials /

Dunning, Andrew J. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (p. 108-112).
27

Experimental measurement of overall effectiveness and internal coolant temperatures for a film cooled gas turbine airfoil with internal impingement cooling

Williams, Randall Paul 24 April 2013 (has links)
A scaled-up gas turbine vane model was constructed in such a way to achieve a Biot number (Bi) representative of an actual engine component, and experiments were performed to collect temperature data which may be used to validate computational fluid dynamics (CFD) codes used in the design of gas turbine cooling schemes. The physical model incorporated an internal impingement plate to provide cooling on the inner wall surface, and film cooling over the external surface was provided by a single row of holes located on the suction side of the vane. A single row of holes was chosen to simplify the operating condition and test geometry for the purpose of evaluating CFD predictions. Thermocouples were used to measure internal gas temperatures and internal surface temperatures over a range of coolant flow rates, while infra-red thermography was used to measure external surface temperatures. When Bi is matched to an actual engine component, these measured temperatures may be normalized relative to the coolant temperature and mainstream gas temperature to determine the overall cooling effectiveness, which will be representative of the real engine component. Measurements were made to evaluate the overall effectiveness resulting from internal impingement cooling alone, and then with both internal impingement cooling and external film cooling as the coolant flow rate was increased. As expected, with internal impingement cooling alone, both internal and external wall surfaces became colder as the coolant flow rate was increased. The addition of film cooling further increased the overall effectiveness, particularly at the lower and intermediate flow rates tested, but provided little benefit at the highest flow rates. An optimal jet momentum flux ratio of I=1.69 resulted in a peak overall effectiveness, although the film effectiveness was shown to be low under these conditions. The effect of increasing the coolant-to-mainstream density ratio was evaluated at one coolant flow rate and resulted in higher values of overall cooling effectiveness and normalized internal temperatures, throughout the model. Finally, a 1-dimensional heat transfer analysis was performed (using a resistance analogy) in which overall effectiveness with film cooling was predicted from measurements of film effectiveness and overall effectiveness without film cooling. This analysis tended to over-predict overall effectiveness, at the lowest values of the jet momentum flux ratio, while under-predicting it at the highest values. / text
28

Design and implementation of a depth-dependent matched filter to maximize signal-to-noise ratio in optical coherence tomography

Boroomand, Ameneh 05 September 2012 (has links)
Obtaining higher depth of imaging is an important goal in Optical Coherence Tomography (OCT) systems. One of the main factors that affect the depth of OCT imaging is the presence of noise. That’s why the study of noise statistics is an important problem. In the first part of this thesis we obtain an empirical estimate of the second order statistics of noise by using a sequence of Time domain (TD) OCT images. These estimates confirm the non-stationary nature of noise in TD-OCT. In the second part of the thesis these estimates are used to design a depth-dependent matched filter to maximize the Signal-to-Noise Ratio (SNR) and increase the Contrast-to-Noise Ratio (CNR) in TD-OCT. By applying our filter to TD-OCT images of both vascular rabbit tissue and a human tooth, both SNR and CNR were increased and a higher imaging depth was achieved.
29

Integrated Surface-Plasmon Waveguides for Optical Communications

Chamberlain, Adam W. 01 January 2005 (has links)
Integrated optics present a potentially low cost and higher performance alternative to electronics in optical communication systems. Surface plasmon waveguides (SPWGs) offer a new approach for manipulating light in integrated optical chips. SPWGs provide several advantages over dielectric waveguides. In this study, a fabrication process for SPWGs is developed. SPWGs are fabricated with various lengths and bend radii to allow for study of absorption and bending losses in the waveguides at telecommunications wavelengths (~1550nm). Finite-element method models of straight, bent, and optically coupled waveguides are developed and analyzed.
30

Design and implementation of a depth-dependent matched filter to maximize signal-to-noise ratio in optical coherence tomography

Boroomand, Ameneh 05 September 2012 (has links)
Obtaining higher depth of imaging is an important goal in Optical Coherence Tomography (OCT) systems. One of the main factors that affect the depth of OCT imaging is the presence of noise. That’s why the study of noise statistics is an important problem. In the first part of this thesis we obtain an empirical estimate of the second order statistics of noise by using a sequence of Time domain (TD) OCT images. These estimates confirm the non-stationary nature of noise in TD-OCT. In the second part of the thesis these estimates are used to design a depth-dependent matched filter to maximize the Signal-to-Noise Ratio (SNR) and increase the Contrast-to-Noise Ratio (CNR) in TD-OCT. By applying our filter to TD-OCT images of both vascular rabbit tissue and a human tooth, both SNR and CNR were increased and a higher imaging depth was achieved.

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