Frequency dependent dielectric constants and its numerical computation through Kramers-Kronig relations and Hilbert transform.

The dielectric constant and loss are important (real and imaginary components) properties of interest to electrical engineers because these two parameters, among others, decide the suitability of a material for a given application. The nature of some physical important parameters is such that frequency dependent real and imaginary components cannot be specified independently from each other. The Kramers-Kronig relations provide the coupling between real and imaginary components. Occasions arise when only one of the components can be readily obtained from theoretical or experimental procedures. The mathematical technique used by Kramers-Kronig relations, which allows one component to be defined in terms of the other is Hilbert transform since &egr;\u27(o) and &egr;″(o) can be shown to be Hilbert transform pairs. The particle formation of this Hilbert transform pair is not an easy task in most instances. One cannot produce an analytical function in order to obtain its Hilbert transformation over a large frequency range. An efficient algorithm is developed to obtain the complex dielectric permittivity of materials over a large frequency range. In this thesis, the algorithm has been verified for both theoretically generated data (Debye equation) and measured data for various high temperature dielectric materials. This procedure calculates the one component of the dielectric constant from its other component by use of the Hilbert transform properties of Kramers-Kronig relation and FFT techniques. Different laboratory equipments and measuring techniques were used in this project and described in detail.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .W44. Source: Masters Abstracts International, Volume: 43-01, page: 0287. Adviser: Govinda Raju. Thesis (M.A.Sc.)--University of Windsor (Canada), 2004

The influence of corporate social responsibility on an employee's sense of belonging

Corporate Social Responsibility (CSR) has increasingly become identified as a societal expectation of companies around the world. The concept has not only risen in significance, but its impacts and potential benefits have become widely recognised by the organisational literature as well as managers. As a result, the influence of CSR practices have been discussed in regards to the numerous stakeholders that hold a vested interest in a company. However, the literature has been predominantly focused on the influence of CSR on external stakeholders such as: shareholders, customers, Non-Governmental Organisations (NGOs) and the general public. As such, the attention attributed to the internal stakeholder group of employees, has been relatively underdeveloped. While focus on this area has begun to emerge throughout the literature, there continues to be a lack of attention given to the effects of CSR on an individual’s sense of belonging within the organisation. As a result, there is a lack of understanding on the nature and extent of this relationship within the existing literature. This qualitative, interview-based study of fourteen respondents, presents results that provide a greater understanding of the relationship between CSR and an individual employee’s sense of belonging. The results uncover the consequences of an organisation’s CSR initiatives on its employees and discusses its influence over fostering a sense of belonging. The findings illustrate that significant impacts upon an employee’s sense of belonging include generating a sense of pride in the organisation, promoting bottom-up, employee-driven initiatives and establishing social relationships amongst colleagues. The findings also recognise the similarly unexplored potential for this influence on employee belonging to be negatively perceived should the value of CSR be overleveraged with external stakeholders. The development of a framework to present the linkages and interconnections between these ideas are able to generate greater understanding of the relationship. The research concludes with practical implications for organisational management to recognise the influence and power to benefit its employees, and ultimately the wider entity, through the implementation of CSR. For a business strategy whose primary implications are concerned with the influence on external stakeholders, this study provides deeper understanding of the unexplored relationship between CSR policies and its influence over an individual employees sense of belonging

Assessment of Atmospheric Deposition and Spatial Variability of Trace Metals in Kandy City and Suburbs using Bio-monitoring Technique in Mosses

Deposition of atmospheric Trace metals (TMs) was investigated in this study through the analysis of mosses that have been grown at nine locations within the Kandy Municipal Council area and its suburbs. Hyophila sp. moss was selected for TM analysis with referring their common availability. After cleaning, dried mosses samples were digested with conc. HNO3 in microwave digesting system. Digested samples were analysed for Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd and Pb using Inductive Coupled Plasma-Mass Spectrometry (ICP-MS). Average TM concentrations in mosses, were resulted with the order of Fe>Al>Zn>Mn>Cu> Pb> Cr>Ni>Cd. The highest and lowest metal concentrations were recorded for Al and Cd as 12,150 and 0.2 mg/kg respectively. Principle factor analysis suggested two major factors; vehicular emission and geographical location, responsible for the TM concentrations in mosses. Factor analysis indicated that approximately about 73% of the TMs in the atmosphere are by the two factors whereas majority from that to be from the vehicular emission. Apart from that, trans-boundary pollution could identify as one of the major factors for TMs in Kandy. Spatial distributions are not significant for the metals that have identified as geogenic origin and others were reported with clear spatial distribution with having highest accumulations in the areas those experiencing higher traffic activities. The ecosystem risk values are still in the acceptable levels in the means of trace metals in mosses. Key words: mosses, bio-monitoring, trace metals, atmospheric depositio

Selective removal of arsenic in water: A critical review

Selective removal of arsenic (As) is the key challenge for any of As removal mechanisms as this not only increases the efficiency of removal of the main As species (neutral As(III) and As(V) hydroxyl-anions) but also allows for a significant reduction of waste as it does not co-remove other solutes. Selective removal has a number of benefits: it increases the capacity and lifetime of units while lowering the cost of the process. Therefore, a sustainable selective mitigation method should be considered concerning the economic resources available, the ability of infrastructure to sustain water treatment, and the options for reuse and/or safe disposal of treatment residuals. Several methods of selective As removal have been developed, such as precipitation, adsorption and modified iron and ligand exchange. The biggest challenge in selective removal of As is the presence of phosphate in water which is chemically comparable with As(V). There are two types of mechanisms involved with As removal: Coulombic or ion exchange; and Lewis acid-base interaction. Solution pH is one of the major controlling factors limiting removal efficiency since most of the above-mentioned methods depend on complexation through electrostatic effects. The different features of two different As species make the selective removal process more difficult, especially under natural conditions. Most of the selective As removal methods involve hydrated Fe(III) oxides through Lewis acid-base interaction. Microbiological methods have been studied recently for selective removal of As, and although there have been only a small number of studies, the method shows remarkable results and indicates positive prospects for the future

Measurement of direct photon production at Tevatron fixed target energies

Measurements of the production of high transverse momentum direct photons by a 515 GeV/c piminus beam and 530 and 800 GeV/c proton beams in interactions with beryllium and hydrogen targets are presented. The data span the kinematic ranges of 3.5 < p_T < 12 GeV/c in transverse momentum and 1.5 units in rapidity. The inclusive direct-photon cross sections are compared with next-to-leading-order perturbative QCD calculations and expectations based on a phenomenological parton-k_T model.Comment: RevTeX4, 23 pages, 32 figures, submitted to Phys. Rev.

Evidence for Parton kT Effects in High pT Particle Production

Inclusive pizero and direct-photon cross sections in the kinematic range 3.5 < pT < 12 GeV/c with central rapidities are presented for 530 and 800 GeV/c proton beams and a 515 GeV/c pi- beam incident on beryllium targets. Current Next-to-Leading-Order perturbative QCD calculations fail to adequately describe the data for conventional choices of scales. Kinematic distributions from these hard scattering events provide evidence that the interacting partons carry significant initial-state parton transverse momentum (kT). Incorporating these kT effects phenomenologically greatly improves the agreement between calculations and the measured cross sections.Comment: 11 pages including 6 pages of figures with caption

Production of pizero and eta mesons at large transverse momenta in pi-p and pi-Be interactions at 515 GeV/c

We present results on the production of high transverse momentum pizero and eta mesons in pi-p and pi-Be interactions at 515 GeV/c. The data span the kinematic ranges 1 < p_T < 11 GeV/c in transverse momentum and -0.75 < y < 0.75 in rapidity. The inclusive pizero cross sections are compared with next-to-leading order QCD calculations and to expectations based on a phenomenological parton-k_T model.Comment: RevTeX4, 15 pages, 15 figures, to be submitted to Phys. Rev.

Experimental Study of the Shortest Reset Word of Random Automata

In this paper we describe an approach to finding the shortest reset word of a finite synchronizing automaton by using a SAT solver. We use this approach to perform an experimental study of the length of the shortest reset word of a finite synchronizing automaton. The largest automata we considered had 100 states. The results of the experiments allow us to formulate a hypothesis that the length of the shortest reset word of a random finite automaton with $n$ states and 2 input letters with high probability is sublinear with respect to $n$ and can be estimated as $1.95 n^{0.55}.

Two-proton correlations from 158 AGeV Pb+Pb central collisions

The two-proton correlation function at midrapidity from Pb+Pb central collisions at 158 AGeV has been measured by the NA49 experiment. The results are compared to model predictions from static thermal Gaussian proton source distributions and transport models RQMD and VENUS. An effective proton source size is determined by minimizing CHI-square/ndf between the correlation functions of the data and those calculated for the Gaussian sources, yielding 3.85 +-0.15(stat.) +0.60-0.25(syst.) fm. Both the RQMD and the VENUS model are consistent with the data within the error in the correlation peak region.Comment: RevTeX style, 6 pages, 4 figures, 1 table. More discussion are added about the structure on the tail of the correlation function. The systematic error is revised. To appear in Phys. Lett.

Event-by-event fluctuations of average transverse momentum in central Pb+Pb collisions at 158 GeV per nucleon

We present first data on event-by-event fluctuations in the average transverse momentum of charged particles produced in Pb+Pb collisions at the CERN SPS. This measurement provides previously unavailable information allowing sensitive tests of microscopic and thermodynamic collision models and to search for fluctuations expected to occur in the vicinity of the predicted QCD phase transition. We find that the observed variance of the event-by-event average transverse momentum is consistent with independent particle production modified by the known two-particle correlations due to quantum statistics and final state interactions and folded with the resolution of the NA49 apparatus. For two specific models of non-statistical fluctuations in transverse momentum limits are derived in terms of fluctuation amplitude. We show that a significant part of the parameter space for a model of isospin fluctuations predicted as a consequence of chiral symmetry restoration in a non-equilibrium scenario is excluded by our measurement.Comment: 6 pages, 2 figures, submitted to Phys. Lett.