The output estimation of a DMU to preserve and improvement of the relative efficiency

In this paper, we consider the inverse BCC model is used to estimate output levels of the Decision Making Units (DMUs), when the input levels are changed and maintain the efficiency index for all DMUs. Since the inverse BCC problem is in the form of a multi objective nonlinear programming model (MONLP), which is not easy to solve. Therefore, we propose a linear programming model, which gives a Pareto-efficient solution to the inverse BCC problem. So far, we propose a model for improvement of the current efficiency value for considered DMU. Numerical examples are, also, used to illustrate the proposed approaches

On the Capacity Region for Secure Index Coding

We study the index coding problem in the presence of an eavesdropper, where the aim is to communicate without allowing the eavesdropper to learn any single message aside from the messages it may already know as side information. We establish an outer bound on the underlying secure capacity region of the index coding problem, which includes polymatroidal and security constraints, as well as the set of additional decoding constraints for legitimate receivers. We then propose a secure variant of the composite coding scheme, which yields an inner bound on the secure capacity region of the index coding problem. For the achievability of secure composite coding, a secret key with vanishingly small rate may be needed to ensure that each legitimate receiver who wants the same message as the eavesdropper, knows at least two more messages than the eavesdropper. For all securely feasible index coding problems with four or fewer messages, our numerical results establish the secure index coding capacity region

Improved Lower Bounds for Pliable Index Coding using Absent Receivers

This paper studies pliable index coding, in which a sender broadcasts information to multiple receivers through a shared broadcast medium, and the receivers each have some message a priori and want any message they do not have. An approach, based on receivers that are absent from the problem, was previously proposed to find lower bounds on the optimal broadcast rate. In this paper, we introduce new techniques to obtained better lower bounds, and derive the optimal broadcast rates for new classes of the problems, including all problems with up to four absent receivers.Comment: An extended version of the same-titled paper submitted to a conferenc

Preferential Pliable Index Coding

We propose and study a variant of pliable index coding (PICOD) where receivers have preferences for their unknown messages and give each unknown message a preference ranking. We call this the preferential pliable index-coding (PPICOD) problem and study the Pareto trade-off between the code length and overall satisfaction metric among all receivers. We derive theoretical characteristics of the PPICOD problem in terms of interactions between achievable code length and satisfaction metric. We also conceptually characterise two methods for computation of the Pareto boundary of the set of all achievable code length-satisfaction pairs. As for a coding scheme, we extend the Greedy Cover Algorithm for PICOD by Brahma and Fragouli, 2015, to balance the number of satisfied receivers and average satisfaction metric in each iteration. We present numerical results which show the efficacy of our proposed algorithm in approaching the Pareto boundary, found via brute-force computation.Comment: An extended version of the same-titled paper accepted for presentation at the 2023 IEEE International Symposium on Information Theory (ISIT

On the capacity region for secure index coding

We study the index coding problem in the presence of an eavesdropper, where the aim is to communicate without allowing the eavesdropper to learn any single message aside from the messages it may already know as side information. We establish an outer bound on the underlying secure capacity region of the index coding problem, which includes polymatroidal and security constraints, as well as the set of additional decoding constraints for legitimate receivers. We then propose a secure variant of the composite coding scheme, which yields an inner bound on the secure capacity region of the index coding problem. For the achievability of secure composite coding, a secret key with vanishingly small rate may be needed to ensure that each legitimate receiver who wants the same message as the eavesdropper, knows at least two more messages than the eavesdropper. For all securely feasible index coding problems with four or fewer messages, our numerical results establish the secure index coding capacity region

Lifestyle risk factor assessment through who step approach in Tabriz, Iran

Background: The aim of this study was to assess the lifestyle behaviour and risk factors for lifestyle-related diseases in East Azerbaijan province, Iran. Methods: A household study using a two-stage cluster sampling method was performed. Tabriz city was randomly selected for data collection among five geographic regions in the East-Azerbaijan province. Short WHO-STEP and Ultra-short version of Socio-Economic Status assessment questionnaire were used. Six hundred households were asked to respond to the STEP questionnaire. Results: A total of 1196 people have participated in the study. People with higher socioeconomic status consumed more fruits, vegetables and fish than the people with lower socioeconomic status. People with academic education less likely to be hypertensive com-pared to people with non-academic education. People with a medium socioeconomic status are less likely to be hypertensive than people with high socioeconomic status. The majority of participants had poor dietary habits. In this study, 17.22%, 7.53% and 4.35% of respon-dents had hypertension, diabetes and depression, respectively. Conclusion: Considering that lifestyle-related risk factors are common among people. Due to the direct link between lifestyle and the occurrence of many chronic diseases, campaigns for and training programs to implement healthy lifestyle habits are recommended.