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Quantum achievability proof via collision relative entropy
, Article IEEE Transactions on Information Theory ; Vol. 60, issue. 12 , 2014 , pp. 7980-7986 ; ISSN: 00189448 ; Gohari, A
2014
Abstract
In this paper, we provide a simple framework for deriving one-shot achievable bounds for some problems in quantum information theory. Our framework is based on the joint convexity of the exponential of the collision relative entropy and is a (partial) quantum generalization of the technique of Yassaee et al. from classical information theory. Based on this framework, we derive one-shot achievable bounds for the problems of communication over classical-quantum channels, quantum hypothesis testing, and classical data compression with quantum side information. We argue that our one-shot achievable bounds are strong enough to give the asymptotic achievable rates of these problems even up to the...
Influence of different nitrogen sources on amount of chitosan production by Aspergillus niger in solid state fermentation
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 27, Issue 1 , 2008 , Pages 47-52 ; 10219986 (ISSN) ; Yaghmaei, S ; Beigi, S. M ; Sharif University of Technology
2008
Abstract
In this study the effect of different nitrogen source substrates on the amount of chitosan production by Aspergillus niger was investigated. A. niger PTCC 5012 from the Persian Type Culture Collection (PTCC) was grown on soy bean, corn seed and canola residues at 30 °C for specified cultivation days under sterilized conditions. Chitosan was extracted from the fungal mycelia using hot alkaline and acid treatment. The results were shown that soy bean residue at moisture of 37% and 8.4 ± 0.26 % of nitrogen content produced the highest amount of chitosan (17.053 ± 0.95 g/kg of dry substrate), after 12 days of incubation. Corn seed residue produced very low amount of chitosan (1.9 ± 0.4 % of...
Simulation of a channel with another channel
, Article IEEE Transactions on Information Theory ; Volume 63, Issue 5 , 2017 , Pages 2659-2677 ; 00189448 (ISSN) ; Yassaee, M. H ; Beigi, S ; Gohari, A ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
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...
On dimension bounds for auxiliary quantum systems
, Article IEEE Transactions on Information Theory ; Vol. 60, Issue. 1 , Jan , 2014 , PP . 368-387 ; ISSN: 00189448 ; Gohari, A ; Sharif University of Technology
2014
Abstract
Expressions of several capacity regions in quantum information theory involve an optimization over auxiliary quantum registers. Evaluating such expressions requires bounds on the dimension of the Hilbert space of these auxiliary registers, for which no nontrivial technique is known; we lack a quantum analog of the Carathéodory theorem. In this paper, we develop a new non-Carathéodory-type tool for evaluating expressions involving a single quantum auxiliary register and several classical random variables. As we show, such expressions appear in problems of entanglement-assisted Gray-Wyner and entanglement-assisted channel simulation, where the question of whether entanglement helps in these...
On the duality of additivity and tensorization
, Article IEEE International Symposium on Information Theory - Proceedings, 14 June 2015 through 19 June 2015 ; Volume 2015-June , 2015 , Pages 2381-2385 ; 21578095 (ISSN) ; 9781467377041 (ISBN) ; Gohari, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
A function is said to be additive if, similar to mutual information, expands by a factor of n, when evaluated on n i.i.d. repetitions of a source or channel. On the other hand, a function is said to satisfy the tensorization property if it remains unchanged when evaluated on i.i.d. repetitions. Additive rate regions are of fundamental importance in network information theory, serving as capacity regions or upper bounds thereof. Tensorizing measures of correlation have also found applications in distributed source and channel coding problems as well as the distribution simulation problem. Prior to our work only two measures of correlation, namely the hypercontractivity ribbon and maximal...
Monotone measures for non-local correlations
, Article IEEE Transactions on Information Theory ; Volume 61, Issue 9 , 2015 , Pages 5185-5208 ; 00189448 (ISSN) ; Gohari, A ; Sharif University of Technology
2015
Abstract
Non-locality is the phenomenon of observing strong correlations among the outcomes of local measurements of a multipartite physical system. No-signaling boxes are the abstract objects for studying non-locality, and wirings are local operations on the space of no-signaling boxes. This means that, no matter how non-local the nature is, the set of physical non-local correlations must be closed under wirings. Then, one approach to identify the non-locality of nature is to characterize the closed sets of non-local correlations. Although non-trivial examples of wirings of no-signaling boxes are known, there is no systematic way to study wirings. In particular, given a set of no-signaling boxes, we...
Two-way channel simulation
, Article IWCIT 2015 - Iran Workshop on Communication and Information Theory, 6 May 2015 through 7 May 2015 ; 2015 ; 9781479982356 (ISBN) ; Gohari, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
In this paper, we consider the problem of simulating one copy of a zero-capacity two-way channel from arbitrary many copies of another two-way channel. The motivation for this problem comes from foundation of quantum physics where zero-capacity two-way channels (a.k.a. no-signaling boxes) serve as the abstract objects for studying non-locality. We provide necessary conditions for the possibility of channel simulation using two measures of correlation, namely maximal correlation and hypercontractivity ribbon. It is shown that when these measures are defined appropriately for two-way channels, they are monotonically decreasing under local operations. Our result allows us to establish a...
Φ-Entropic measures of correlation
, Article IEEE Transactions on Information Theory ; Volume 64, Issue 4 , 2018 , Pages 2193-2211 ; 00189448 (ISSN) ; Gohari, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
A measure of correlation is said to have the tensorization property if it does not change when computed for i.i.d. copies. More precisely, a measure of correlation between two random variables X, Y denoted by rho (X, Y), has the tensorization property if ρ(Xn, Yn)=ρ (X, Y) where (Xn, Yn) denotes n i.i.d. copies of (X, Y). Two well-known examples of such measures are the maximal correlation and the hypercontractivity ribbon (HC ribbon). We show that the maximal correlation and the HC ribbon are special cases of the new notion of Φ-ribbons, defined in this paper for a class of convex functions Φ. Φ-ribbon reduces to the HC ribbon and the maximal correlation for special choices of Φ, and is a...
Low power receiver with merged N-path LNA and mixer for MICS applications
, Article AEU - International Journal of Electronics and Communications ; Volume 117 , 2020 ; Safarian, A ; Sharif University of Technology
Elsevier GmbH
2020
Abstract
In this paper, a low power receiver for medical implant communication service (MICS) is presented. Low power design is vital in the MICS applications since the implanted chip has to work for a long time without the need to change its battery. As a result, a merged N-path low noise amplifier (LNA) and mixer block is proposed. In this structure, the LNA and down-conversion mixer share a transconductance to lower the overall power consumption. An N-path feedback is utilized around the shared transconductance not only to improve the LNA selectivity and relax the linearity requirements but also to downconvert the radio frequency (RF) component and create the intermediate frequency (IF) signal. In...
Link Prediction in Complex Networks
, M.Sc. Thesis Sharif University of Technology ; Beigi, Hamid (Supervisor)
Abstract
With the growth of social networks, link prediction has attracted great attention. Completing partially observed networks, recognizing errors in observed links, predicting the network’s future structure to aid decision making, and presenting users with favorable links are some the motivations that have made link prediction important and effective for complex networks. In this work, we analyze link prediction in DBLP’s author network and attempt to increase the accuracy of state-of-the-art link prediction techniques by extracting discriminative information from the available metadata. Abstracts are an important resource that indicate an author’s field of study. Extracting the concepts an...
Assessing the Hydro-mechanical Behavior of Undisturbed Collapsible Soils by Conducting Unsaturated Odeometer Tests Case Study: Gorgan Loess
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
The deposits in many regions in Iran, particularly eastern zones like Golestan, Semnan, Khorasan, Yazd, Kerman, Hormozgan, Sistan and Baluchestan provinces consist of Aeolian deposits of loess, which are categorized as collapsible soils. This kind of soil show sufficient shear strength and low deformability in dry or natural condition. However, if a structure is built on the soil and water seeps or infiltrates into the soil due to several reasons such as sewer leakage, water seepage or heavy precipitations in a way that its moisture reaches to a critical value, the interparticle bonds may break or the present suction in the soil may decrease in a way that the soil experiences sudden...
Leveraging User-Item Interactions for Trust Prediction
, M.Sc. Thesis Sharif University of Technology ; Jalili, Mahdi (Supervisor)
Abstract
Trust prediction, the ability to identify how much to trust to allocate an unknown user, is an important prerequisite toward the development of scalable on-line e-commerce communities. We are more likely to purchase an item from a seller on an e-commerce websites such as eBay or Amazon, if our trusted acquaintances have reported positive experiences with that seller in the past. Reviews from trusted users will carry more weight towards the purchasing decision than reviews from anonymous or unknown customers. Thus, these platforms must support computational mechanisms for propagating trust between users. One of the significant challenges in the trust prediction problem is the unprecedented...
A Thesis Submitted in Partial Fulfillment of the Requirement for the Degree of Master of Science in Computer Engineering
, M.Sc. Thesis Sharif University of Technology ; Beigi, Hamid (Supervisor)
Abstract
The modern science of networks has brought significant advances to our understanding of complex systems. One of the most relevant features of graphs representing real systems is community structure, or clustering, i. e. the organization of vertices in clusters, with many edges joining vertices of the same cluster and comparatively few edges joining vertices of different clusters. Such clusters, or communities, can be considered as fairly independent compartments of a graph, playing a similar role like, e. g., the tissues or the organs in the human body. Detecting communities is of great importance in sociology, biology and computer science, disciplines where systems are often represented as...
Intrusion Detection System in Smart Grids
, M.Sc. Thesis Sharif University of Technology ; Amini, Morteza (Supervisor)
Abstract
Smart grids are the new generation of power grids that combine the power distribution grid with the communications network. The purpose of these networks is to create a secure, two-way infrastructure for the transmission of power and information. The complex structure of smart grids, along with the inherent vulnerabilities of physical systems, old devices and protocols on the network and the need for backward compatibility, have created serious cyber risks to critical assets and infrastructures. The difference between these types of networks and conventional computer networks has made the security mechanisms developed in conventional computer networks not very suitable for these types of...
Phase behavior and rheology of emulsions in an alkaline/cosolvent/crude oil/brine system
, Article Petroleum Science and Technology ; Volume 34, Issue 3 , 2016 , Pages 207-215 ; 10916466 (ISSN) ; Hemmati, M ; Shariat Panahi, H ; Masihi, M ; Karam Beigi, M. S ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
Phase behavior of active crude oil/alkaline was systematically studied in the presence of cosolvents. For this purpose, several factors have been considered: alkaline concentration, oil concentration, and type of brine. The best composition was used to generate emulsion for rheology and displacement tests. Furthermore, precipitation of alkaline was eliminated by its synergy with EDTA. Next, rheology of emulsion was analyzed by which a Power law model was developed that indicates non-Newtonian behavior of emulsion. Moreover, the viscosity of emulsion was reduced by the addition of cosolvent as well as by the increase of alkaline concentration. Finally, the best formulation (containing...
Findings of DTI-p maps in comparison with T 2 /T 2 -FLAIR to assess postoperative hyper-signal abnormal regions in patients with glioblastoma 08 Information and Computing Sciences 0801 Artificial Intelligence and Image Processing
, Article Cancer Imaging ; Volume 18, Issue 1 , 2018 ; 14707330 (ISSN) ; Safari, M ; Ameri, A ; Shojaee Moghadam, M ; Arbabi, A ; Tabatabaeefar, M ; Salighehrad, H ; Sharif University of Technology
BioMed Central Ltd
2018
Abstract
Purpose: The aim of this study was to compare diffusion tensor imaging (DTI) isotropic map (p-map) with current radiographically (T 2/T 2 -FLAIR) methods based on abnormal hyper-signal size and location of glioblastoma tumor using a semi-automatic approach. Materials and methods: Twenty-five patients with biopsy-proved diagnosis of glioblastoma participated in this study. T 2, T 2 -FLAIR images and diffusion tensor imaging (DTI) were acquired 1 week before radiotherapy. Hyper-signal regions on T 2, T 2 -FLAIR and DTI p-map were segmented by means of semi-automated segmentation. Manual segmentation was used as ground truth. Dice Scores (DS) were calculated for validation of semiautomatic...
Study of Climate Change Impacts on Temporal and Spatially Varying Groundwater Recharge
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
Increase of concentration of CO2 and other greenhouse gases will have significant effect on global climate. Climate change affects precipitation and hydrology, which in turn influences recharge to groundwater. Recharge to groundwater is an important source, which has the main role in groundwater resources availability. To trace these changes to recharges and its consequent effect on groundwater state, a combined modeling of climate change and groundwater is necessary. In This study impact of climate change on groundwater recharge in two different climatic plains of Karkheh river basin in Khuzestan, Iran, has been investigated using a physically-based methodology that can be used for...
Towards a self-adaptive service-oriented methodology based on extended SOMA
, Article Frontiers of Information Technology & Electronic Engineering ; Volume 16, Issue 1 , January 2015 , Pages 43-69 ; Moaven, S ; Habibi, J ; Beigi, G ; Naser-Shariat, M ; Sharif University of Technology
January 2015
Abstract
We propose a self-adaptive process (SAP) that maintains the software architecture quality using the MAPE-K standard model. The proposed process can be plugged into various software development processes and service-oriented methodologies due to its explicitly defined inputs and outputs. To this aim, the proposed SAP is integrated with the service-oriented modeling and application (SOMA) methodology in a two-layered structure to create a novel methodology, named self-adaptive service-oriented architecture methodology (SASOAM), which provides a semi-automatic self-aware method by the composition of architectural tactics. Moreover, the maintenance activity of SOMA is improved using...
Towards a self-adaptive service-oriented methodology based on extended SOMA
, Article Frontiers of Information Technology and Electronic Engineering ; Volume 16, Issue 1 , 2015 , Pages 43-69 ; 20959184 (ISSN) ; Moaven, S ; Habibi, J ; Beigi, G ; Naser Shariat, M ; Sharif University of Technology
2015
Abstract
We propose a self-adaptive process (SAP) that maintains the software architecture quality using the MAPE-K standard model. The proposed process can be plugged into various software development processes and service-oriented methodologies due to its explicitly defined inputs and outputs. To this aim, the proposed SAP is integrated with the service-oriented modeling and application (SOMA) methodology in a two-layered structure to create a novel methodology, named self-adaptive service-oriented architecture methodology (SASOAM), which provides a semi-automatic self-aware method by the composition of architectural tactics. Moreover, the maintenance activity of SOMA is improved using...
Towards a self-adaptive service-oriented methodology based on extended SOMA
, Article Journal of Zhejiang University: Science C ; Volume 16, Issue 1 , 2015 , Pages 43-69 ; 18691951 (ISSN) ; Moaven, S ; Habibi, J ; Beigi, G ; Naser Shariat, M ; Sharif University of Technology
2015
Abstract
We propose a self-adaptive process (SAP) that maintains the software architecture quality using the MAPE-K standard model. The proposed process can be plugged into various software development processes and service-oriented methodologies due to its explicitly defined inputs and outputs. To this aim, the proposed SAP is integrated with the service-oriented modeling and application (SOMA) methodology in a two-layered structure to create a novel methodology, named self-adaptive service-oriented architecture methodology (SASOAM), which provides a semi-automatic self-aware method by the composition of architectural tactics. Moreover, the maintenance activity of SOMA is improved using...