Lossy Kernelization

In this paper we propose a new framework for analyzing the performance of preprocessing algorithms. Our framework builds on the notion of kernelization from parameterized complexity. However, as opposed to the original notion of kernelization, our definitions combine well with approximation algorithms and heuristics. The key new definition is that of a polynomial size $\alpha$-approximate kernel. Loosely speaking, a polynomial size $\alpha$-approximate kernel is a polynomial time pre-processing algorithm that takes as input an instance $(I,k)$ to a parameterized problem, and outputs another instance $(I',k')$ to the same problem, such that $|I'|+k' \leq k^{O(1)}$. Additionally, for every $c \geq 1$, a $c$-approximate solution $s'$ to the pre-processed instance $(I',k')$ can be turned in polynomial time into a $(c \cdot \alpha)$-approximate solution $s$ to the original instance $(I,k)$. Our main technical contribution are $\alpha$-approximate kernels of polynomial size for three problems, namely Connected Vertex Cover, Disjoint Cycle Packing and Disjoint Factors. These problems are known not to admit any polynomial size kernels unless $NP \subseteq coNP/poly$. Our approximate kernels simultaneously beat both the lower bounds on the (normal) kernel size, and the hardness of approximation lower bounds for all three problems. On the negative side we prove that Longest Path parameterized by the length of the path and Set Cover parameterized by the universe size do not admit even an $\alpha$-approximate kernel of polynomial size, for any $\alpha \geq 1$, unless $NP \subseteq coNP/poly$. In order to prove this lower bound we need to combine in a non-trivial way the techniques used for showing kernelization lower bounds with the methods for showing hardness of approximationComment: 58 pages. Version 2 contain new results: PSAKS for Cycle Packing and approximate kernel lower bounds for Set Cover and Hitting Set parameterized by universe siz

On the Optimality of Pseudo-polynomial Algorithms for Integer Programming

In the classic Integer Programming (IP) problem, the objective is to decide whether, for a given $m \times n$ matrix $A$ and an $m$-vector $b=(b_1,\dots, b_m)$, there is a non-negative integer $n$-vector $x$ such that $Ax=b$. Solving (IP) is an important step in numerous algorithms and it is important to obtain an understanding of the precise complexity of this problem as a function of natural parameters of the input. The classic pseudo-polynomial time algorithm of Papadimitriou [J. ACM 1981] for instances of (IP) with a constant number of constraints was only recently improved upon by Eisenbrand and Weismantel [SODA 2018] and Jansen and Rohwedder [ArXiv 2018]. We continue this line of work and show that under the Exponential Time Hypothesis (ETH), the algorithm of Jansen and Rohwedder is nearly optimal. We also show that when the matrix $A$ is assumed to be non-negative, a component of Papadimitriou's original algorithm is already nearly optimal under ETH. This motivates us to pick up the line of research initiated by Cunningham and Geelen [IPCO 2007] who studied the complexity of solving (IP) with non-negative matrices in which the number of constraints may be unbounded, but the branch-width of the column-matroid corresponding to the constraint matrix is a constant. We prove a lower bound on the complexity of solving (IP) for such instances and obtain optimal results with respect to a closely related parameter, path-width. Specifically, we prove matching upper and lower bounds for (IP) when the path-width of the corresponding column-matroid is a constant.Comment: 29 pages, To appear in ESA 201

Contemporary Issues in Current Account Operations in Pakistani IBs - Sharia Compliant Solution

Contemporary Sharia scholars have three stances about the Current Account Operations in Pakistani Islamic Banks (IBs) i.e., (i) Ijarah based contract (ii) Wadi'ah based contract, and (iii) Qard based contract. This paper is an attempt to delve into the root causes of the differences of scholars and to find the Sharia-compliant solution acceptable for all. Descriptive as well as applied approaches are used in this paper. Clearing of ambiguity on this issue may result in twofold benefits: from the public point of view, it would satisfy practising Muslims which may result in form of huge deposits in this account (ii) from IBs viewpoint the Current Account is a bonus deposit

Utilization of PVC Particles to Improve the Bending Properties of Epoxy and Unsaturated Polyester

Two sets of polymeric composites were formed. The first set included epoxy as matrix ,while the second set included unsaturated polyester (UP) as matrix. The two sets were reinforced with Polyvinyl Chloride (PVC) at  different volume fractions. Each set was formed into two groups: one was allowed to cure at room temperature and the other was post cured at 40°C for 4hr . The percent of reinforcing and the curing temperature can affect the  behavior of composites. The epoxy composites is the highest in flexural properties than unsaturated polyester composites after reinforcing with thermoplastic material (PVC) . Keywords: epoxy, unsaturated polyester, polyvinyl chloride (PVC), bending.

Workability and compressive strength of eco-friendly concrete based on waste ceramic particles

Eco-materials are becoming the one of the important matters to be addressed in industries and academics owing to reduce the impact of synthetic materials on environment. On the other hand, waste materials have becoming an equal important matter in term of disposal and their impact on environment. In civil engineering, exploring any potential eco-materials for structural components is the ambition of many engineering and environmental researchers. In this project, an attempt is made to explore the potential of using waste ceramic particles in concrete. The structure and the compressive characteristics of the developed materials with different waste ceramic particle percent are investigated. Different concrete samples were prepared and tested. The failure mechanisms were determined after the completion of the experiments. The optimum percent of waste ceramic particles in concreate were determined from workability, compressive strength and structure of the concrete. Compressive strength of the developed concretes were tested at different curing duration of 7, 14 and 28 days. Visual examination and scanning electron microscope were used to observe the failure mechanism. The experimental results were in high agreement with the published recent and related works. The content of the waste ceramic particle controlled all the characteristics of the ceramics, i.e. workability, compressive strength, and the structure. Increase in the content of the waste ceramic particles deteriorate the strength of the concrete especially at content of above 25 wt. %. Despite of that the reduction in the strength at low percent of waste ceramic particle were within the industrial recommended ranges. Also, from environmental point of view, a promising results are identified and 25 wt % of waste ceramic particles in concrete is highly recommend. The failure of the concreate was commonly due to the crack generation and/or propagation in the bonding region of the particles and the cement. At high percent of waste ceramic particles, there is micro- and mac-cracks propagated which resulted in the poor performance of the concreate at this high percent of particle

An FPT Algorithm for Elimination Distance to Bounded Degree Graphs

In the literature on parameterized graph problems, there has been an increased effort in recent years aimed at exploring novel notions of graph edit-distance that are more powerful than the size of a modulator to a specific graph class. In this line of research, Bulian and Dawar [Algorithmica, 2016] introduced the notion of elimination distance and showed that deciding whether a given graph has elimination distance at most k to any minor-closed class of graphs is fixed-parameter tractable parameterized by k [Algorithmica, 2017]. They showed that Graph Isomorphism parameterized by the elimination distance to bounded degree graphs is fixed-parameter tractable and asked whether determining the elimination distance to the class of bounded degree graphs is fixed-parameter tractable. Recently, Lindermayr et al. [MFCS 2020] obtained a fixed-parameter algorithm for this problem in the special case where the input is restricted to K?-minor free graphs. In this paper, we answer the question of Bulian and Dawar in the affirmative for general graphs. In fact, we give a more general result capturing elimination distance to any graph class characterized by a finite set of graphs as forbidden induced subgraphs

Assessment of Corporate Social Responsibility (CSR) awareness and practices in manufacturing sector of Pakistan

Globalization and mass communication have significantly influenced the socio-economic growth of countries and organizations are under immense pressure to develop their businesses in a more socially responsible way. Consequently, Corporate Social Responsibility (CSR) has emerged as a business development concept. CSR acknowledgement is low in south Asian countries both at state and corporate levels. Pakistan, being a developing country, is no exception and the manufacturing sector, which is the third largest contributing sector to the economy, is facing the challenge of corporate social compliance. This study explores the awareness level amongst employees in the manufacturing sector and also evaluates the practices of CSR activities in these organizations. The study is mainly focused on the textile and automobile sectors and shows greater CSR awareness in the automobile sector than the textile sector; however, there are many organizations where the concept of CSR is unknown. The findings of this research will help organizations in enhancing understanding of CSR amongst employees and will also allow manufacturing industries to improve their implementation against identified weak areas. Increased levels of social compliance will ultimately help organizations in promoting their businesses in the global market

Aligning accounting education and training : a comparative study

This study aims to build an aligned model of AE&T for the KSA by benefiting from the comparative analysis of AE&T in the UK and the KSA. The researcher depended on the Wilson model (2002) which is the first model to refer to the alignment of AE&T to produce effective accounting practitioners. The researcher cover the last three stages from this model and focused on accounting students. The researcher determined the propositions that needed to be tested by comparative analysis between AE&T in these two countries. Those propositions reflect all the three stages, namely: university accounting education, professional accounting training and professional accounting practice and CPE. The researcher adopted a case study approach, which was felt to be the most appropriate method in addressing the research aim, enabling an aligned model of AE&T to be built. The main source of data collection was reviewing and analysing current literature and by conducting face-to-face in-depth interviews and documentary sources. Cross-case analysis was used as the main approach for analysing data. The researcher produced a model of AE&T by determining the positive features of AE&T systems in the UK and the KSA, based on comparative analysis.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Surgical Approaches to Congenital Anomalies of Esophagus

With prevalence of about 1 in 3000 live births, pediatric surgeons commonly deal with esophageal abnormalities, which may provide substantial clinical complications. Surprisingly, the embryologic processes underlying esophageal atresia (EA) with or without tracheoesophageal fistula (TEF), one of the hallmark disease entities of pediatric surgery, have only lately been largely uncovered. When it comes to the treatment of congenital esophageal abnormalities, notably esophageal atresia and tracheoesophageal fistula, surgical methods are essential. In order to address the anatomical abnormalities and restore normal function, surgical correction is often necessary in the care of congenital esophageal anomalies, including esophageal atresia and tracheoesophageal fistula. In this review we are going to cover surgical approaches to repair those malformations, long-term outcomes, and latest developments in esophageal surgical approaches