251 research outputs found
The Transmuted Weibull-Pareto Distribution
A new generalization of the Weibull-Pareto distribution called the transmuted Weibull-Pareto distribution is proposed and studied. Various mathematical properties of this distribution including ordinary and incomplete moments, quantile and generating functions, Bonferroni and Lorenz curves and order statistics are derived. The method of maximum likelihood is used for estimating the model parameters. The flexibility of the new lifetime model is illustrated by means of an application to a real data set
Mining software repositories to support software evolution
Software evolution represents a major phase in the development life cycle of software systems. In recent years, software evolution has been recognized as one of the most important and challenging areas in the field of software engineering. Studies even show that 65-80% of the system lifetime will be spent on maintenance and evolution activities. Software repositories, such as versioning and bug tracking systems are essential parts of various software maintenance activities. Given the often large amounts of information stored in these repositories, researchers have proposed to mine and analyze these large knowledge bases in order to study and support various aspects of the evolution of a software system. In this thesis, we introduce a common ontological representation to support the mining and analysis of software repositories. In addition to this common representation, we introduce the SVN-Ontologizer and Bugzilla-Ontologizer tools that provide automation for both data extraction from remote repositories and ontology populations. A case study is presented to illustrate the applicability of the present approach in supporting software maintainers during the analysis and mining of these software repositorie
Thermal Degradation Studies of Alternating Copolymers and Their Related Homopolymers
Alternating copolymers posses a uniquely regular chain structure in which the two different type of monomer (A and B) units present in strictly alternating ordered sequence in the chain backbone, i.e. -ABABABABA-. These types of material have a novel macromolecular structure. Their thermal degradation behaviour remains largely unexplored and it was the interest in the present research to discover what are the patterns of behaviour and how they compare with those of random copolymers. For the aforesaid reasons, various alternating copolymers and their related homopolymers were synthesised, characterised and their thermal degradation behaviour was studied under programmed and isothermal heating experiments using TVA, TG and DSC techniques. A general description of major types of degradation processes which may occur during thermal decomposition is described in Chapter 1. The brief description of thermal degradation behaviour of the alternating copolymers is also included in this Chapter. Chapter 2 summarises the application and experimental techniques employed in the present study. The first part deals with the thermal analysis techniques and the second part describes the techniques used to identify the degradation products both quantitatively and qualitatively. Monomer preparation, polymerisation and characterisation of monomers is considered in detail in Chapter 3. This also includes a brief description of the calculation determination of monomer feed for the preparation for the copolymers. Vinyl acetate, isopropenyl acetate and methacrylic acid were used in several alternating systems, so it was appropriate to consider the thermal degradation behaviour of these monomers as homopolymer. The thermal degradation behaviour of poly(vinyl acetate) PVA and poly(isopropenyl acetate), PIPAc are described in Chapter 4 and 8. The two homopolymers show degradation features in common. Both show a two stage decomposition under programmed heating, the first involves the elimination of acetic acid in a zipper deacetylation of short zip length. The second stage reaction, occurring at higher temperatures, involves fragmentation of the backbone and the formation of aromatics and cold ring fraction. Chain scission is much more extensive in the case of PIPAc than for PVA, because all the acetate groups are linked to the tertiary C atom, which is considered as a initiation point for the thermal degradation. Hence thermal dissociation is very easy in the case of PIPAc which makes polymer thermally less resistant. In Chapter 5, the studies of the thermal decomposition of poly(methacrylic acid), PMAA are described. PMAA exhibits two decomposition stages. In the first stage, there is intra- and inter molecular anhydride formation between COOH groups with water elimination. In the second stage, between 350 and 50
SMALL AND MEDIUM-SIZE ENTERPRISES IN PAKISTAN: DEFINITION AND CRITICAL ISSUES
SMEs play a vital role in the development of an economy. Thecontribution of Pakistani SMEs is less as compared to other countries, yet their significance cannot be denied. The SME sector is facing multifarious problems that made it difficult to contribute to the nation‘s GDP. This paper attempts to focus on the major constraints faced by the SMEs. The basic problem starts with no defined and standardized size for SMEs. The paper examines the definitions of SMEs given by different government organizations in Pakistan with some possible suggestion for one standard SME definition (in terms of size). This paper also highlights the critical issues of Pakistani SMEs such as financial, human, physical and technological. The paper concludes with some brief prospects by recommending a few implications for policy
QuSecNets: Quantization-based Defense Mechanism for Securing Deep Neural Network against Adversarial Attacks
Adversarial examples have emerged as a significant threat to machine learning
algorithms, especially to the convolutional neural networks (CNNs). In this
paper, we propose two quantization-based defense mechanisms, Constant
Quantization (CQ) and Trainable Quantization (TQ), to increase the robustness
of CNNs against adversarial examples. CQ quantizes input pixel intensities
based on a "fixed" number of quantization levels, while in TQ, the quantization
levels are "iteratively learned during the training phase", thereby providing a
stronger defense mechanism. We apply the proposed techniques on undefended CNNs
against different state-of-the-art adversarial attacks from the open-source
\textit{Cleverhans} library. The experimental results demonstrate 50%-96% and
10%-50% increase in the classification accuracy of the perturbed images
generated from the MNIST and the CIFAR-10 datasets, respectively, on commonly
used CNN (Conv2D(64, 8x8) - Conv2D(128, 6x6) - Conv2D(128, 5x5) - Dense(10) -
Softmax()) available in \textit{Cleverhans} library
Variation in the Quality of Life within Punjab: Evidence from MICS, 2007-08
Since quality of life research is essentially concerned with
measuring and monitoring welfare. In order to measure quality of life,
one must have a theory of what makes up a good life [Cobb (2000)]. There
is a variety of such theories and notions of what constitutes a ‗good
life‘ and correspondingly different concepts of welfare and quality of
life have been developed. Various approaches and operationalisations are
to be distinguished, each of which reveals a different concept of
welfare and thus highlights different components and dimensions [Noll
(2000)]. Among the various efforts to operationalise welfare in general
and the quality of life concept in particular, two contrary approaches
are to be distinguished, which define the two extreme positions on a
broad continuum of concepts currently available: the Scandinavian level
of living approach [Erickson (1993)] and the American quality of life
approach [Campbell (1976)]. The Scandinavian approach focuses almost
exclusively on resources and objective living conditions, whereas the
American approach emphasises the subjective well-being of individuals as
a final outcome of conditions and processes
The failure of the Muslim league in post-colonial Pakistan: a critical appraisal
Significance: Nations states in developing societies were a legacy of colonial rule. The catastrophic world wars
of the European metropolis had spillover effects in developing countries, where colonialism was replaced by
communism and nationalism among post-colonial peoples. The political parties who led anticolonial nationalist
movements employed demonstrations, agitation, and mobilization at broader level for their intentions, but
without the existential enemy of the colonial oppressor they were prone to division and faced numerous
incidentals, natural and hostile challenges, particularly in the case of Pakistan, whose birth was deliberately
sabotaged by British imperialism as well as Indian nationalism. Nevertheless, the Muslim League was
essentially successful in its fundamental aim of creating a Muslim state in South Asia and began to administer it
after independence. This study explores the character and role played by the post-colonial political parties,
especially the Muslim League, whose consequences left the effects on dictatorship generally and on politics
particularly that have shaped the development of South and Central Asia ever since
Merger & acquisition strategy for growth, improved performance and survival in the financial sector
This paper aims to provide comparative information on mergers & acquisition activities in the banking sector of Pakistan. This study used accounting ratios to analyze the financial performance of banks in Pakistan after merger and acquisitions. The study utilized secondary data which were taken from Thomson Financial Services Worldwide M&A database, financial statements of bank’s corporate website and Pakistan stock exchange. In this study, financials for eleven years (2005-2016) were analyzed by using ratios. In spite of certain limitations, accounting ratios are still reflected as an easy and reliable analytical tool. Ratio analysis, being a time-tested method, is most frequently employed in all financial decision-making processes. The results show that the financial performance of banking sector of Pakistan in the capacities of profitability, and leverage, has been quite satisfactory before the merger deal. It means that merger deal fails to improve the financial performance of the bank, and banks merge with other small or equal size banks only to capture market share, to open Islamic window, for cost-cutting, to create synergy, to gain efficient resources and to unlock hidden value
- …