This paper introduces a new and ubiquitous framework for establishing achievability results in network information theory problems. The framework uses random binning arguments and is based on a ...duality between channel and source coding problems. Furthermore, the framework uses pmf approximation arguments instead of counting and typicality. This allows for proving coordination and strong secrecy problems, where certain statistical conditions on the distribution of random variables need to be satisfied. These statistical conditions include independence between messages and eavesdropper's observations in secrecy problems and closeness to a certain distribution (usually, i.i.d. distribution) in coordination problems. One important feature of the framework is to enable one to add an eavesdropper and obtain a result on the secrecy rates for free. We make a case for generality of the framework by studying examples in a variety of settings including channel coding, lossy source coding, joint source-channel coding, coordination, strong secrecy, feedback, and relaying. In particular, by investigating the framework for the lossy source coding problem over broadcast channel, it is shown that the new framework provides a simple alternative scheme to the hybrid coding scheme. In addition, new results on secrecy rate region (under strong secrecy criterion) of wiretap broadcast channel and wiretap relay channel are derived. In a set of accompanied papers, we have shown the usefulness of the framework to establish achievability results for coordination problems, including interactive channel simulation, coordination via relay and channel simulation via another channel.
Development of Smart Grid and deployment of smart meters in large scale has raised a lot of concerns regarding customers’ privacy. Consequently, several schemes have been proposed to overcome the ...above mentioned issue. These schemes mainly rely on data aggregation as a method of protecting users’ privacy from the grid operators. However, the main problem with most of these schemes is the fact that they require a large amount of processing power at the meter side. This, together with the fact that smart meters don’t usually have a powerful processor, can cause the unavailability of smart meter data at the required time for operators of the grid, and at the same time prevents smart meters from performing their other duties, such as managing the home area network. In this paper, we propose an efficient privacy preserving data aggregation scheme, based on elliptic curves. In our scheme, each smart meter signs its encrypted data and sends it to the aggregator. After receiving the data, the aggregator verifies the incoming messages and aggregates them, without the need to decrypt the data received from each smart meter. The aggregator signs the aggregated messages and sends it to the operation center. At the end, the smart meters’ data are obtained and verified by the operation center. In addition to providing efficient computation cost, for the users, our protocol also satisfies the security requirements of smart grid data aggregation schemes. We provide security analysis of the proposed scheme as well as comparisons to show the efficiency of our scheme on computation and communication overheads.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Dynamic index coding is a practical generalization of conventional index coding that deals with real dynamic traffic streams. We identify the code-constrained capacity region of a dynamic index ...coding problem with a complete bi-directional side information graph and introduce the performance metric of dynamic index coding gain to measure how dynamic index coding reduces the required data transmissions. A greedy dynamic index coding scheme is proposed that achieves the maximum coding gain almost everywhere in the identified capacity region. Although the greedy scheme attains the maximum coding gain, its selfish nature may unacceptably increase transmission delay. To address this issue, a time-shared friendly dynamic index coding scheme is introduced that achieves the maximum coding gain over the entire capacity region and offers a lower delay than its greedy counterpart. To obtain the minimum delay, a constrained optimization problem is formulated to tune time-sharing weights in the friendly scheme. The closed-form solution of the optimization is derived for the special two-flow case. Furthermore, the results and analysis are extended to dynamic index coding problems with arbitrary side information graphs. We also use analytical and simulation results to provide graphical intuition for the obtained results.
Many USVs are equipped with navigation, guidance and control (NGC) algorithms due to human errors that is present in manual navigation of surface vehicles. The Morvarid, a catamaran shaped boat is ...designed and developed for plotting hydrography map of harbours. To control it autonomously, a fusion algorithm based on EKF, search ball and potential field concept is developed. Some main parameters of dynamic model is derived based on experimental tests and the algorithm is evaluated using hardware-in-the-loop concept. The obstacle avoidance algorithm is assessed for different obstacles in size and position. It is concluded that although the developed algorithm is robust and precise even in the presence of environmental disturbances, however installing powerful thrusters would boost maneuverability more than that is.
•The USV rigid body dynamic model is defined by combination of experimental, simulation and conformance to some texts.•Combing EKF, search ball and potential field algorithms in a fusion concept could navigate the USV more accurately.•A successful obstacle avoidance is possible by considering the velocity vector of USV and obstacle and size of obstacle.
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Recently, the field of lightweight cryptography (LWC) has emerged in response to the security needs of low-cost, widely used technology. It is essential to implement an encryption approach with ...access control to give less complex, more flexible, and safe access to sensitive data. In this work, a novel lightweight chaotic encryption approach with fuzzy access control is presented to encrypt light images in the IoT domain, while maintaining image quality. With the aid of multiplexer modeling and information shift register technology, the algorithm’s design combines random and chaotic mapping approach based on a specific password key with a predetermined number of fuzzy logic shifts on the password key for the image pixels. Further, to extract the private key with complexity and boost defense against attacks, a shift register and logical xor combination is employed. The simulation of the proposed model for AVR microcontroller has been done under MATLAB software and the design of various encryption components has been used to implement lightweight mapping. The proposed system has been evaluated in terms of histogram analysis, adjacent pixel correlation analysis, contrast analysis, homogeneity analysis, energy analysis, NIST analysis, error mean square analysis, information entropy, pixel number change rate, integrated mean change intensity, peak signal-to-noise ratio, and time complexity. Remarkably, the proposed technique has demonstrated high efficiency. The simulation results show that the homogeneity, energy, contrast, NPCR, and UACI criteria have improved by 11.5%, 13.1%, 19%, 0.53%, and 0.12%, respectively, compared to other methods in other articles.
Background
The emergence of antibiotic‐resistant Helicobacter pylori strains in recent years has increased the need for finding an alternative in the post‐antibiotic era. One of the fields being ...considered for this purpose is antimicrobial peptides. The aim of this review was to provide an obvious scheme from the studied anti‐H. pylori peptides and to investigate their common features.
Method
First, all of the antimicrobial peptides with their anti‐H. pylori effects have been proved up to September 2018 were selected and their information including structure, mechanism of action, and function was reviewed. To achieve this, three databases of PubMed, Scopus, and Web of science were used.
Results
A total of 9 groups containing 22 antimicrobial peptides were found with demonstrated anti‐H. pylori effects. The nine groups included pexiganan, tilapia piscidins, epinecidin‐1, cathelicidins, defensins, bicarinalin, odorranain‐HP, PGLa‐AM1, and bacteriocins. Most of the antimicrobial peptides, not all, had common features such as the ability to kill antibiotic‐resistant strains, having α‐helical structure, being cationic, with high positive charge and isoelectric point.
Conclusion
Antimicrobial peptides with anti‐H. pylori effects have the potential to replace the antibiotics, especially in the post‐antibiotic era, if a rapid and low‐cost production method would be found.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
7.
Simulation of a Channel With Another Channel Haddadpour, Farzin; Yassaee, Mohammad Hossein; Beigi, Salman ...
IEEE transactions on information theory,
05/2017, Volume:
63, Issue:
5
Journal Article
Peer reviewed
In this paper, we study the problem of simulating a discrete memoryless channel (DMC) from another DMC under an average-case and an exact model. We present several achievability and infeasibility ...results, with tight characterizations in special cases. In particular, for the exact model, we fully characterize when a binary symmetric channel can be simulated from a binary erasure channel when there is no shared randomness. We also provide infeasibility and achievability results for the simulation of a binary channel from another binary channel in the case of no shared randomness. To do this, we use the properties of Rényi capacity of a given order. We also introduce a notion of "channel diameter" which is shown to be additive and satisfy a data processing inequality.
Meet in the middle (MITM) attack is one of the most important and applicable methods for cryptanalysis of block ciphers. In this paper, a more generalized method for MITM attack is considered. For ...this purpose, a notion, namely cut-set, is utilized by which several numbers of MITM attacks can be performed. However, manual investigation on these cases is time-consuming and sometimes not error-free. Therefore, a new search algorithm is also provided to obtain proper attacks in a timely manner. For examination, this new search algorithm, which could make an automated attack along with some certain ideas, is applied on HIGHT, Piccolo-128, CRAFT and AES-128 block ciphers. The least time complexities which are obtained by generalized MITM attack on full HIGHT, Piccolo-128, CRAFT and AES-128 are 2 125.08 , 2 126.78 , 2 123.25 and 2 125.53 , respectively. The results on full-round CRAFT are, to the best of our knowledge, the first cryptanalysis results in the single-key model except the designers' investigations. In addition, the results show some improvements for complexities of all the attacks, especially on HIGHT.
Abstract
Chronic rhinosinusitis (CRS) is a pathological condition characterized by persistent inflammation in the upper respiratory tract and paranasal sinuses. The epithelium serves as the first ...line of defense against potential threats and protects the nasal mucosa. The fundamental mechanical barrier is formed by the cell-cell contact and mucociliary clearance (MCC) systems. The physical-mechanical barrier is comprised of many cellular structures, including adhesion junctions and tight junctions (TJs). To this end, different factors, such as the dysfunction of MCC, destruction of epithelial barriers, and tissue remodeling, are related to the onset and development of CRS. Recently published studies reported the critical role of different microorganisms, such as
Staphylococcus aureus
and
Pseudomonas aeruginosa
, in the induction of the mentioned factors. Bacteria could result in diminished ciliary stimulation capacity, and enhance the chance of CRS by reducing basal ciliary beat frequency. Additionally, bacterial exoproteins have been demonstrated to disrupt the epithelial barrier and induce downregulation of transmembrane proteins such as occludin, claudin, and tricellulin. Moreover, bacteria exert an influence on TJ proteins, leading to an increase in the permeability of polarized epithelial cells. Noteworthy, it is evident that the activation of TLR2 by staphylococcal enterotoxin can potentially undermine the structural integrity of TJs and the epithelial barrier through the induction of pro-inflammatory cytokines. The purpose of this article is an attempt to investigate the possible role of the most important microorganisms associated with CRS and their pathogenic mechanisms against mucosal surfaces and epithelial barriers in the paranasal sinuses.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Purpose: The purpose of the present study was to investigate the effect of job stress on the relationship between organizational ostracism and knowledge hiding in the metropolitan area of Ahvaz.
...Methodology: The research was applied and carried out using an analytical survey. The statistical population of the study included all the employees of the Ahvaz Metropolitan Municipality, over 3000 people, 341 of whom were selected as the research sample by stratified random sampling. The data were collected as part of a field study using questionnaires from previous studies on organizational ostracism (Chang et al., 2021), knowledge hiding (Demirkasimoglu, 2016), and job stress (Wooten et al., 2010). The validity of the instrument was approved formally and its reliability was confirmed using Cronbach's alpha coefficient (0.830, 0.869, and 0.884) levels, respectively. The data were analyzed with the structural equation modeling method and AMOS software.
Findings: The test of research hypotheses showed that there is a relationship between organizational ostracism by knowledge hiding (β=0.51 and t-Value=8.5) and job stress (β=0.73 and t-Value 11.59) and there is a significant relationship between job stress and knowledge hiding (β=0.44 and t-Value=7.805). In addition, the results revealed that job stress had a direct effect on the causal relationship between organizational ostracism and knowledge hiding (β=0.828) and that (β=0.321) is significant at (p<0.05).
Conclusion: It is concluded that organizational ostracism brings about negative consequences such as job stress and hidden knowledge. It means that the organization members miss the opportunity to use communication networks between organization members and knowledge resources. It also increases the costs of providing services and dependence on knowledge resources outside the organization.
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