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An analysis of the logistics performance index of EU countries with an integrated MCDM model

Abstract

Countries can check the performance of their logistics’ activities to determine their competitiveness in trade logistics. One way to check these performances is to analyze the country’s LPI value in detail which is released by the WB every two years. When calculating the LPI, six indicators (criteria) are taken into account. The weights (importance level) of these criteria are important for countries which would like to focus more on the most important criteria and move their ranking up in the LPI list. However the WB takes into account indicators (criteria) weights equally when calculating LPI values. In order to overcome this problem some studies have used subjective weighting methods and others have used objective weighting methods. Both methods have advantages and disadvantages. The aim of this study is to integrate two weighting methods (subjective (SWARA) and objective (CRITIC)) in determining the weights of criteria in order to balance the two weighting methods. Unlike other studies in the literature this study combines two weighting methods. Additionally the PIV method, which is seldom used to address any MCDM problem, is used in this study and a new integrated MCDM model is introduced to literature. In this respect this study contributes to the literature.

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Boyd and Wong Type Fixed Point Theorems in Partial Metric Spaces

Abstract

In this paper, we present fixed point results for Boyd and Wong type [3] generalized contractive condition in partial metric spaces. In particular, we generalize the fixed point results due to Akkouchi [1] in complete partial metric spaces in which the continuity requirement for a mapping is relaxed to obtain the results. In addition to that we present a common fixed point theorem for a pair of maps. An illustrative example is also constructed to exhibit the results.

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Common coupled fixed point theorems for two pairs of weakly compatible mappings in Menger metric spaces

Abstract

In this paper, we prove some common coupled fixed point theorems for contractive mappings in Menger metric spaces under geometrically convergent t-norms. Also, we prove common fixed point theorems for pairs of weakly compatible mappings, which generalize the results of Jian-Zhong Xiao and al (2011). The main results is supported by a suitable examples.

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Controllability of some bilinear and semilinear parabolic problems

Abstract

We present in this paper a survey of recent results on the controllability of the parabolic system governed by bilinear control. We first discuss the problem of global controllability which corresponds to the question of whether the solution of the system can be driven to a given state at a some finite time by means of a control. We give some results on the global controllability of bilinear and semilinear reaction-diffusion equations. After this we introduce the case of partial controllability with the control acting on a subregion of the domain. Illustrative examples are also provided.

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Do foreign direct investment and savings promote economic growth in Poland?

Abstract

This study aims to investigate the impact of savings and foreign direct investment on economic growth in Poland. Savings play an important role in achieving sustainable growth. High saving rates are also an important tool to increase resilience to financial shocks. The economic climate that emerged following the financial crisis revealed problems with the economy of Poland to obtain foreign financing. The decrease in foreign direct investment has led to an unpredictable economic environment for developing countries such as Poland. The decrease in foreign direct investment has led to lower growth rates for an emerging market such as the economy of Poland. The relationship economic growth rate, saving and foreign direct investment are examined for Poland over the period 1992-2016 by using the Autoregressive Distributed Lag (ARDL) bounds testing approach. According to this approach there is a cointegration relationship between the series and a 1% increase in savings which leads to a 0.81% increase on economic growth rate. Also a 1% increase in foreign direct investment (FDI) leads to a 1.52% increase in the economic growth rate.

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Does corporate governance influence firm performance? Evidence from India

Abstract

Corporate Governance (CG) in India has undergone major transformation in the recent past with the enactment of Companies Act, 2013 and revision of SEBI’s Listing Agreement. Though some studies were undertaken in the Indian context few conventional aspects of CG have been repetitively addressed with conflicting results. The aim of this study is to examine the impact of some prominent CG attributes such as board size, board independence, role duality, board’s gender diversity, ownership concentration and audit committee independence on both market as well as accounting based measures of firm performance (FP). To this end the study uses a sample of top 100 non-financial and non-utility firms listed on the Bombay Stock Exchange (BSE) for the period of 2014-2018 and employs two stage least square with instrumental variables technique of estimation which takes into account potential endogeneity in CG-FP relationship. The findings reveal a significant positive impact of board size, ownership concentration and audit committee independence on market based measure of FP while board independence is found to have a significant negative impact on accounting based measure of FP. Moreover role duality and gender diversity are not associated with FP. The outcome of this study highlights how the relationship between CG and FP works in the unique institutional setting of India and it should be of interest to regulators, practitioners and other market participants.

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Effect of Torso Non-Homogeneities in the quasi-static inverse problems arising in electrocardiology

Abstract

In the present paper, an homogeneous and non-homogeneous inverse problem constrained by the stationary problem in electrocardiology representing the heart, lungs surfaces, and torso model is investigated. Our goal is to reconstruct the electrical potentials on the surface of the heart from the information obtained non invasively on the torso surface. The existence and uniqueness of solution for the heart-torso problem and the related inverse problem is assessed, and the primal and dual problems are discretized using a finite element method. We present some preliminary numerical experiments using an efficient implementation of the proposed scheme in homogeneous and non-homogeneous cases. Finally, we demonstrate the effect of the non-homogeneity on the reconstructed epicardial potential and show that the inverse ECG problem cannot be solved by the classical BEM (boundary element method).

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An Efficient Algorithm for Reconstruction Images Corrupted by Some Multiplicative Noises

Abstract

In this paper, we propose a novel hybrid model for restoration of images corrupted by multiplicative noise. Using a MAP estimator, we can derive a functional whose minimizer corresponds to the denoised image we want to recover. The energies studied here are inspired by image restoration with non linear variable exponent [1, 2], and it is a combination of fast growth with respect to low gradient and slow growth when the gradient is large. We study a mathematical framework to prove the well posedness of the minimizer problem and we introduce the associated evolution problem, for which we derive numerical approaches. At last, compared experimental results distinctly demonstrate the superiority of the proposed model, in term of removing some muliplicative noise while preserving the edges and reducing the staircase effect.

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The empirical analysis of financial reports of companies in Croatia: Benford distribution curve as a benchmark for first digits

Abstract

The financial numbers game is unfortunately alive and doing well. One of the forensic accounting techniques is based on Benford’s Law and is used for the detection of unusual transactions, anomalies or trends. The aim of this paper is to test whether the financial statements of Croatian companies deviate from Benford’s Law distribution. The financial statements of 24 companies that are in the pre-bankruptcy settlement process and 24 companies that are not in the pre-bankruptcy settlement process were analysed using the Benford’s Law test of the first digit distribution for the period from 2015 to 2018. The data used to calculate the first digits of distribution were taken from the Zagreb Stock Exchange. The chi-square test has shown that the observed companies that are not in the process of pre-bankruptcy settlement do not have the first digit distribution which follows the Benford’s Law distribution. The Kolmogorov-Smirnov Z test has shown that the distribution of the first digits from the financial statements of companies listed on the Zagreb Stock Exchange fits to Benford’s Law distribution.

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Existence Results For A Class Of Nonlinear Degenerate Elliptic Equations

Abstract

In this paper we are interested in the existence of solutions for Dirichlet problem associated with the degenerate nonlinear elliptic equations

{-div[𝒜(x,u)ω1+𝒝(x,u,u)ω2]=f0(x)-j=1nDjfj(x)inΩ,u(x)=0onΩ,

in the setting of the weighted Sobolev spaces.

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