Blind Curvelet based Denoising of Seismic Surveys in Coherent and Incoherent Noise Environments

The localized nature of curvelet functions, together with their frequency and dip characteristics, makes the curvelet transform an excellent choice for processing seismic data. In this work, a denoising method is proposed based on a combination of the curvelet transform and a whitening filter along with procedure for noise variance estimation. The whitening filter is added to get the best performance of the curvelet transform under coherent and incoherent correlated noise cases, and furthermore, it simplifies the noise estimation method and makes it easy to use the standard threshold methodology without digging into the curvelet domain. The proposed method is tested on pseudo-synthetic data by adding noise to real noise-less data set of the Netherlands offshore F3 block and on the field data set from east Texas, USA, containing ground roll noise. Our experimental results show that the proposed algorithm can achieve the best results under all types of noises (incoherent or uncorrelated or random, and coherent noise)

A framework for assessing the impact of investment in human capital development on organisational performance

A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Doctor of PhilosophyThis thesis aims to empirically examine the impact of investing in human capital development on organisational performance. It examines the relevant literature on human resource accounting and human capital development from different methodological strands and synthesises its findings in the development of a new theoretical framework. The literature review points out the challenges that remain to enterprises in quantifying and measuring the benefits of human capital development. The proposed framework takes into account those conceptual aspects of human resource accounting that how investment in human capital development can be measured to investigate the financial returns for organisations. The said framework also considers various contextual contingent factors that lead to a higher level of human resource sophistication and consequently which could affect the organisational performance. On the basis of relationships predicated between the key constructs of the theoretical model, a list of hypotheses is developed. The research methodology adopted by the researcher is based on the ideology of objectivism. It adopts a functionalist paradigm and a set of philosophical assumptions related to realism, positivism, determinism and nomotheticism. Its approach is deductive in terms of theory testing, employs the survey as its primary research strategy and uses mainly quantitative and partially qualitative methods of data collection. It adopts a cross-sectional time horizon and seeks to be exploratory and explanatory in nature. The main sample is comprised of 320 leading manufacturing organisations in Pakistan. A self-administered questionnaire is designed to collect data from human resource managers or individuals dealing with human resource development within the Pakistani manufacturing enterprises. SPSS-19 and SmartPLS packages are employed to analyse the quantitative data. Partial least squares method of structural equation modelling (PLS-SEM) is adopted for the testing of hypotheses. The study’s quantitative results provide an evidence of association between investment in the development of human capital and the benefits to organisations. Furthermore, organisations that invest in training and development programmes have high employee productivity which ultimately contributes towards high organisational performance. The qualitative results help in identifying the major problems faced by management of the Pakistani manufacturing organisation in evaluating investments in HCD and their impact on organisational performance. This research is a pioneer work in Pakistan and thereby contributes to the existing global literature on management accounting in general and on human resource accounting in particular

Impact of Optimism Bias on Investment Decision: Evidence from Islamabad Stock Exchange, Pakistan

Many economic and financial theories suggest that investor make rational decision making on the basis of all available information. According to standard finance humans are rational but behavioral finance treats them normal. So we can say human’s sentiments and emotions are involved in decision making process. The main focus of this research is to determine the effect of psychological behavior on investment decision. In this study we examine the impact of optimism bias on investment decision. Results show significant relationship with investment decision. This study is carrying out on sample of convenience of investor. 20 items Questionnaire is used to collect the data based on bias and investment decision .This research conduct in Islamabad. Impact of optimism bias on investment decision is seen to be significant. This study will help investor to identify their biases, its influence on their investment decision and formulated different strategies to reduce the irrational behavior. Key words: optimism bias, investment decisio

Millimeter wave radio channels: properties, multipath modeling and simulations

Based on the characterization of realistic radio channels, results presented in this dissertation lead towards an understanding that when moving up to the higher frequencies, frequency itself does not play a significant role in defining the channel modeling methodology. In fact, how a propagation channel is illuminated is of fundamental importance. Therefore, millimeter wave (mmWave) system properties such as a high antenna directivity and system bandwidth are shown to have a great influence on the channel model definition. In this thesis, a fundamental assumption made in the state-of-the-art millimeter wave wireless channel models is challenged. It has been shown that Rayleigh-Rice fading assumption made in the state-of-the-art channel models for resolvable channel taps does not remain valid. This is mainly due to the sparse multipath illumination caused by high antenna directivity and high bandwidth of a mmWave system.Studies presented in this thesis are based on the characterization of realistic radio channels obtained from exhaustive channel sounding campaigns. Mainly, three fundamental problems of wireless channel modelling have been investigated for millimetre wave (mmWave) radio channel modelling application, namely (i) Frequency dependence of propagation, (ii) Impact of antenna directivity on the channel model definition, and (iii) Impact of system bandwidth on the radio channel modelling. A detailed description of these problems is as follows: (i) Frequency Dependence of Propagation. Multi-band measurement campaigns arecarried out using directional antennas which do an omni-directional scan of the propagation environment. During the measurements, Tx-Rx systems are placed at fixed positions and the propagation environment remained as static as possible. Using synthesized omni-directional power delay profiles (PDPs), we aim to investigate if there exists a frequency dependency in the multipath dispersion statistics, e.g. delay and angular spreads. (ii) Impact of Antenna Directivity on the Channel Model Definition. Small-scale fading measurements are carried out which emulate a scenario, where a radio communication link is established through a single multipath cluster which is illuminated using antennas with different Half Power Beam Widths (HPBW). The major goal here is to investigate the impact of spatial multipath filtering on the small-scale fading due to high antenna directivity. In particular, the impact on variations in the receive signal strength and the validity of narrowband wide-sense stationary assumption (both in time and frequency domains) is investigated. (iii) Impact of System Bandwidth on the Radio Channel Modelling. Small-scale fading measurements are used to illuminate multipath clusters in a lecture room scenario. The primary objective is to investigate the impact of high system bandwidth on variations in the receive signal strength, randomness in the cross-polarization power ratio (XPR) and richness of the multipath scattering. Based on the characterization of realistic radio channels, results presented in this dissertation lead towards an understanding that when moving up to the higher frequencies, frequency itself does not play a significant role in defining the channel modelling methodology. In fact, how a propagation channel is illuminated is of fundamental importance. Therefore, mmWave system properties such as a high antenna directivity and system bandwidth are shown to have a high influence on the channel model definition. In general, fade depth scaling as a function of system bandwidth is quite well understood. We demonstrate that, the high antenna directivity of mmWave systems result in a further reduction in the fading depth. In addition, we explore some new directions to this line of research which are based on the second-order statistical analysis of the channel impulse response (CIR) vector. Our results emphasize that, fading statistics of resolvable channel taps in a mmWave radio channel cannot be modelled as Rayleigh-Rice distributed random variables. This is primarily due to the fact that channels with sparse scattering conditions are illuminated due to high antenna directivity and bandwidth of mmWave systems. Consequently, the complex Gaussian random variable assumption associated with Rayleigh-Rice fading distributions does not remain valid. Further, it has been demonstrated that, high antenna directivity and bandwidth of mmWave systems also raise a question mark on the validity of wide-sense stationary (WSS) assumption in the slow-time domain of mmWave radio channels. Results presented in this contribution are novel and they provide theoretically consistent insights into the measured radio channel.In dieser Arbeit werden drei grundlegende Probleme der Modellierung von Drahtloskanalen fur die Anwendung bei der Funkkanalmodellierung im Millimeterwellenbereich (mmWave) untersucht, namlich (i) die Frequenzabhangigkeit der Ausbreitung, (ii) der Einfluss der Antennenrichtwirkung auf die Definition des Kanalmodells und (iii) der Einfluss der Systembandbreite auf die Funkkanalmodellierung. Die detaillierte Beschreibung dieser Probleme lautet wie folgt: (i) Frequenzabhangigkeit der Ausbreitung. Mehrband-Messkampagnen werden mitRichtantennen durchgefuhrt, die eine omnidirektionale Abtastung der Ausbreitungsumgebung vornehmen. Wahrend der Messungen werden die Tx-Rx-Systeme an festen Positionen platziert und die Ausbreitungsumgebung bleibt so statisch wie moglich. Mit Hilfe von synthetisierten omnidirektionalen Verzogerungs-Leistungsprofilen soll untersucht werden, ob es eine Frequenzabhangigkeit in der Mehrwegeausbreitungsstatistik gibt, z.B. in der Verzogerung und der Winkelspreizung. (ii) Einfluss der Antennenrichtwirkung auf die Definition des Kanalmodells. Es werden Messungen des schnellen Schwunds durchgefuhrt, die ein Szenario emulieren, bei dem eine Funkverbindung uber ein einzelnes Mehrwege-Cluster aufgebaut wird, das mit Antennen mit unterschiedlichen Strahlbreiten ausgeleuchtet wird. Das Hauptzielist hier die Untersuchung des Einflusses der raumlichen Filterung auf den schnellen Schwund aufgrund der hohen Antennenrichtwirkung. Insbesondere wird die Auswirkung auf Variationen der Empfangssignalstarke und die Gultigkeit der Annahme der schmalbandigen Stationaritat im weiteren Sinne (sowohl im Zeit- als auch im Frequenzbereich) untersucht. (iii) Einfluss der Systembandbreite auf die Funkkanalmodellierung. Messungen desschnellen Schwunds werden verwendet, um Mehrwege-Cluster in einem Horsaal-Szenario auszuleuchten. Das primare Ziel ist es, den Einfluss einer hohen Systembandbreite auf die Variationen der Empfangssignalstarke, die Zufalligkeit des Kreuzpolarisationsverhaltnisses und die Reichhaltigkeit der Mehrwegstreuung zu untersuchen. Basierend auf der Charakterisierung realistischer Funkkanäle führen die in dieser Dissertation vorgestellten Ergebnisse zu dem Verständnis, dass beim Ubergang zu höheren Frequenzen die Frequenz x selbst keine signifikante Rolle bei der Definition der Kanalmodellierungsmethodik spielt. Vielmehr ist es von grundlegender Bedeutung, wie ein Ausbreitungskanal ausgeleuchtet wird. Daher zeigt sich, dass mmWave-Systemeigenschaften wie eine hohe Antennenrichtcharakteristik und Systembandbreite einen hohen Einfluss auf die Definition des Kanalmodells haben. Im Allgemeinen ist die Skalierung der Schwundtiefe als Funktion der Systembandbreite ziemlich gut verstanden. Wir zeigen, dass die hohe Antennenrichtwirkung von mmWave-Systemen zu einer weiteren Reduzierung der Schwundtiefe führt. Zusätzlich erforschen wir einige neue Richtungen in diesem Forschungsbereich, die auf der Analyse der Statistik zweiter Ordnung des Kanalimpulsantwort-Vektors basieren. Unsere Ergebnisse unterstreichen, dass die Schwund-Statistiken der auflösbaren Kanalabgriffe in einem mmWave-Funkkanal nicht als Rayleigh-Rice-verteilte Zufallsvariablen modelliert werden können. Dies liegt vor allem daran, dass durch die hohe Antennenrichtwirkung und Bandbreite von mmWave-Systemen Kanale mit spärlichen Streubedingungen ausgeleuchtet werden. Folglich ist die Annahme komplexer Gaus’scher Zufallsvariablen, die mit Rayleigh-Rice Schwundverteilungen verbunden ist, nicht mehr gültig. Des Weiteren wird gezeigt, dass die hohe Antennenrichtwirkung und Bandbreite von mmWave-Systemen auch die Gültigkeit der Annahme von Stationarität im weiteren Sinne im Slow-Time-Bereich von mmWave-Funkkanälen in Frage stellt. Die in diesem Beitrag vorgestellten Ergebnisse sind neuartig und bieten theoretisch konsistente Einblicke in den gemessenen Funkkanal

Forecasting Inflation: Autoregressive Integrated Moving Average Model

This study compares the forecasting performance of various Autoregressive integrated moving average (ARIMA) models by using time series data. Primarily, The Box-Jenkins approach is considered here for forecasting. For empirical analysis, we used CPI as a proxy for inflation and employed quarterly data from 1970 to 2006 for Pakistan. The study classified two important models for forecasting out of many existing by taking into account various initial steps such as identification, the order of integration and test for comparison. However, later model 2 turn out to be a better model than model 1 after considering forecasted errors and the number of comparative statistics

Interest Rates, Government and Private Investments and Pakistan Economy: An Analysis of Three Decades

The paper investigates the relationship between interest rates and private investment with the economic growth in Pakistan. One of the primary plans of economic policies is to increase investment that is important for better economic performance .using time series analysis and annual data from 1980 - 2010. The structural equation model is used to find out the relations of the variables in the model with help of the regression equations. The empirical results indicate that private investment, government expenditures and labor force have significant positive effect on gross domestic product but foreign direct investment has negative and statistically significant relation with gross domestic product. There also exists a unique long-run relationship between economic growth and its determinants, including interest rate. The results imply that the behavior of interest rate is important for economic growth in view of the relationships between interest rates and investment and investment and growth. Private investment, government expenditure and foreign direct investment first individually estimated than used the estimated values in main equation of the study. Keywords: Gross domestic product, interest rate, private investment

Impact of Training on Employee Performance in the Context of Telecommunication Sector of D. G. Khan, (Pakistan)

This paper examines the relationship between training and its impact on employees performance in the context of “Telecommunication Sector of D. G. Khan” Pakistan. There are three hypotheses and three objectives of this research study and by using a questionnaire 150 employees were chosen for data collection from telecommunication. “ANOVA and SPSS” Correlation coefficient was used for data analysis. Independent variable of this study is Training and dependent variable is employee performance. The independent variable training has two determinants salary and job involvement. Results showed Positive relationships between Training, Salary and Job Involvement with Employee Performance