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A utilization of wireless sensor network in smart homes, reviewing its combination with modern cellular networks
, Article Proceedings of the 2011 International Conference on Communication and Industrial Application, ICCIA 2011, 26 December 2011 through 28 December 2011 ; December , 2011 , Page(s): 1 - 5 ; 9781457719172 (ISBN) ; Rafiei Sakhaei, M. H ; Sharif University of Technology
2011
Abstract
In this paper, after reviewing the basic structure for implementing WSN in smart grid, we would give a case study for implementation of such a structure in a smart home. It will be shown that using new generation cellular network structure, gives a basic improvement the infrastructure needed for gathering the information and taking a real time monitoring and control of a simplified model of a smart grid executed as a smart home. We will take the advantage of computer simulations to show the reliability of this method and finally, we will analyze the advantages of using this proposed structure in a smart grid. [1, 4]
Failure analysis of a first stage gas turbine blade
, Article Engineering Failure Analysis ; 2010 ; 13506307 (ISSN) ; Abouali, S ; Akbari Garakani, M
2010
Spatiotemporal dynamics of chlorophyll-a in the Gorgan Bay and Miankaleh Peninsula biosphere reserve: Call for action
, Article Remote Sensing Applications: Society and Environment ; Volume 30 , 2023 ; 23529385 (ISSN) ; Danesh Yazdi, M ; Sharif University of Technology
Elsevier B.V
2023
Abstract
Gorgan Bay (GB) and Miankaleh Peninsula biosphere reserve has faced an endangering condition because of a significant water loss and quality degradation due to intensive eutrophication. However, a synoptic view of the spatiotemporal dynamic of eutrophication is missing. In this study, we first used MODIS data to trace the long-term trend of eutrophication in GB between 2003 and 2021. To investigate the intra-annual variability of Chl-a in GB at a much higher spatial resolution, we developed an Artificial Neural Network (ANN) algorithm that uses Sentinel-2 imagery to map monthly Chl-a in the water year 2020–2021. Finally, we explored the major physical controls on eutrophication in GB....
Experimental Study of Mechanical Behavior of a Particular Metallic Material under Cyclic Loading
, M.Sc. Thesis Sharif University of Technology ; Khonsari, Vahid (Supervisor)
Abstract
One of the requirements of designing structures is the properties of their materials. The behavior of the material should be studied under the same conditions (loading regime) as it would be in practice. Regarding the structures which are subjected to cyclic loading, usually the results of monotonic tests on their material are used for their analysis under cyclic loads. Taking this fact into account that the behavior of materials under cyclic loading is normally much different from that under monotonic loading, one should doubt the results of the analyses of structures subjected to cyclic loading for which monotonic test results are used. In this project, the properties of steel rebars under...
New techniques for localization based information theoretic secret key agreement
, Article 2017 14th International ISC (Iranian Society of Cryptology) Conference on Information Security and Cryptology, ISCISC 2017, 6 September 2017 through 7 September 2017 ; 2018 , Pages 70-76 ; 9781538665602 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
2018
Abstract
We consider a source model for information theoretic secret key agreement based on the distance among the nodes, in a basic system consisting of two legitimate users and an eavesdropper. The legitimate nodes try to agree on a reliable and secure key based on their noisy observation of distance between them. We propose two methods to enhance system utility: 1) Artificial Noise Forwarding (ANF), 2) transmission in different beam directions (multi-antenna transmission). In the first method artificial noise is used to worsen e a vesdropper's distance estimation and in the second method beacon signals are sent in different directions and the virtual distances in different beam directions are used...
Private authentication: optimal information theoretic schemes
, Article 2019 IEEE Information Theory Workshop, ITW 2019, 25 August 2019 through 28 August 2019 ; 2019 ; 9781538669006 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The main security service in the connected world of cyber physical systems necessitates to authenticate a large number of nodes privately. In this paper, the private authentication problem is considered, that consists of a certificate authority, a verifier, many legitimate users (prover) and any arbitrary number of illegitimate users. Each legitimate user wants to be authenticated (using his personal key) by the verifier, while simultaneously wants to stay completely anonymous (even to the verifier and the CA). On the other hand, an illegitimate user must fail to authenticate himself. We analyze this problem from an information theoretical perspective. First, we propose a general interactive...
Anonymous Mutual Authentication: An Information Theoretic Framework
, Article 9th Iran Workshop on Communication and Information Theory, IWCIT 2021, 19 May 2021 through 20 May 2021 ; 2021 ; 9781665400565 (ISBN) ; Mirmohseni, M ; Aref, M. R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
We consider the anonymous mutual authentication problem, which consists of a certificate authority, single or multiple verifiers, many legitimate users (provers) and any arbitrary number of illegitimate users. The legal verifier and a legitimate user must be mutually authenticated to each other using the user's key, while the identity of the user must stay unrevealed. An attacker (illegitimate prover) as well as an illegal verifier must fail in authentication. A general interactive information theoretic framework in a finite field is proposed, where the normalized total key rate as a metric for reliability is defined. Maximizing this rate has a trade-off with establishing anonymity. The...
User and Data Privacy: An Information-Theoretic Approach
, Ph.D. Dissertation Sharif University of Technology ; Aref, Mohammad Reza (Supervisor)
Abstract
Today, ensuring privacy alongside other security features is essential for many services, and with the advancement of various technologies, different aspects of privacy are emerging. In most systems, establishing privacy is a challenging issue that may conflict with other system features or reduce the effectiveness of other system parameters. This dissertation studies privacy from the perspective of information theory in authentication as one of the significant security challenges. Applications of this issue include vehicular networks, sensor networks, and services based on blockchain technology. We consider various privacy features in the authentication problem, which includes a certificate...
Quantifying the Relative Share of Factors in Drying Gorgan Bay and Miankaleh Peninsula by Studying Long-Term Water Balance
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
GB and Miankale Wetland are one of the most valuable water areas in the country from an ecological perspective, providing a habitat for a wide range of aquatic species and birds as well as providing a platform for fishing and tourism for locals. Recently, this wildlife refuge has experienced a crisis of reduced water levels and degraded water quality. Past studies have examined how fluctuations in the Caspian Sea water level affect GB's water quantity and quality. Due to the critical situation of Gorgan Bay, other factors affecting its water balance and upstream basin need to be examined, such as ground water flow and consumption, precipitation, and evaporation, and how they all affect the...
Failure analysis of a repaired gas turbine nozzle
, Article Engineering Failure Analysis ; 13506307 (ISSN) ; Abouali, S ; Akbari Garakani, M ; Sharif University of TechnologyThe Study of the Effect of Surfactant on the Liquid Drop Motion In Fluid
, M.Sc. Thesis Sharif University of Technology ; Firoozabadi, Bahar (Supervisor) ; Afshin, Hossein (Co-Supervisor)
Abstract
The drop motion in fluid and the mass transfer is one of the most interesting and favorite topics that has attracted the attention of many researchers. Knowing the functions of the factors affecting the deformation and the process of mass transfer and the effects of the addition of the surfactant, improve the efficiency of the related industrial processes.In this regard, the present study examines how the shape and speed of a moving Newtonian drop in a Newtonian fluid, the mass transfer of soluble material from inside the drop to the surrounding fluid and also the study of the effect of surfactant on the dynamics of moving droplet is studied numerically. During the drop movement, the...
Learning to bid in forward electricity markets using a no-regret algorithm
, Article Electric Power Systems Research ; Volume 234 , 2024 ; 03787796 (ISSN) ; Majdi, D ; Kazempour, J ; Kamgarpour, M ; Sharif University of Technology
2024
Abstract
It is a common practice in the current literature of electricity markets to use game-theoretic approaches for strategic price bidding. However, they generally rely on the assumption that the strategic bidders have prior knowledge of rival bids, either perfectly or with some uncertainty. This is not necessarily a realistic assumption. This paper takes a different approach by relaxing such an assumption and exploits a no-regret learning algorithm for repeated games. In particular, by using the a posteriori information about rivals’ bids, a learner can implement a no-regret algorithm to optimize her/his decision making. Given this information, we utilize a multiplicative weight-update...
Computational modelling of the therapeutic outputs of photodynamic therapy on spheroid-on-chip models
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 258 , 2024 ; 10111344 (ISSN) ; Teymouri, F ; Khatami, M ; Hosseini, S. N ; Sharif University of Technology
2024
Abstract
Photodynamic therapy (PDT) is a medical radio chemotherapeutic method that uses light, photosensitizing agents, and oxygen to produce cytotoxic compounds, which eliminate malignant cells. Recently, Microfluidic systems have been used to analyse photosensitizers (PSs) due to their potential to replicate in vivo environments. While prior studies have established a strong correlation between reacted singlet oxygen concentration and PDT-induced cellular death, the effects that the ambient fluid flow might have on the concentration of oxygen and PS have been disregarded in many, which limits the reliability of the results. Herein, we coupled the transport of oxygen and PS throughout the ambient...
Mechanical characteristics of die-wall friction on the compaction process of metal nano-powders
, Article Powder Technology ; Volume 444 , 2024 ; 00325910 (ISSN) ; Sameti, A. R ; Kazempour, Z ; Pourkermani, A. G ; Sharif University of Technology
2024
Abstract
The die-wall friction is one of the influential mechanical factors in the metal nano-powder compaction process that can noticeably impress the densification behavior of nanoparticles. In this study, the uniaxial cold compaction process of aluminum nano-powders, which are initially loaded into the nickel die-walls, is analyzed using the molecular dynamics (MD) method. The influence of die-wall friction is studied on the nano-powder compaction process. The results illustrate the effect of frictional die-walls on the characteristics of relative density–pressure and stress–strain curves, the pressure distribution of nano-powders, and the final green product. The evolution of the die-wall...
Nonlinear interstory drift contours for idealized forward directivity pulses using "modified fish-bone" models
, Article Advances in Structural Engineering ; Volume 18, Issue 5 , May , 2015 , Pages 603-627 ; 13694332 (ISSN) ; Khosravi, H ; Jamnani, H. H ; Sharif University of Technology
Multi-Science Publishing Co. Ltd
2015
Abstract
Four 5-, 10-, 20- and 30-story moment frames, representing low-, mid-, and two high-rise structures, were subjected to a great number of idealized directivity pulses. The amplitudes and periods of pulses vary from 0.02 g to 1.0 g and 0.5 to 12 sec, respectively. Over 1400 nonlinear dynamic analyses of low- to high-rise moment frames were performed which were feasible through using modified fish-bone model. The distribution of interstory drift along the height was studied and two applied contours were proposed: (i) the maximum interstory drift contour, and (ii) the critical story contour. These contours were demonstrated versus the ratio of natural period of the structure to the pulse period...
Analysis of singularities of a 3DOF parallel manipulator based on a novel geometrical method
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Sadeghian, H ; Roozbehani, H ; Zohoor, H ; Sharif University of Technology
2006
Abstract
In this article singular points of a parallel manipulator are obtained based on a novel geometrical method. Here we introduce the constrained plain method (CPM) and some of its application in parallel mechanism. Given the definition of constraint plane (CP) and infinite constraint plane (ICP) the dependency conditions of constraints is achieved with the use of a new theorem based on the Ceva geometrical theorem. The direction of angular velocity of a body is achieved by having three ICPs with the use of another theorem. Finally, with the use of the above two novel theorems singularities of the 3UPF_PU mechanism are obtained. It should be emphasized that this method is completely geometrical,...
Melting enthalpy and entropy of freestanding metallic nanoparticles based on cohesive energy and average coordination number
, Article Journal of Physical Chemistry C ; Volume 115, Issue 35 , August , 2011 , Pages 17310-17313 ; 19327447 (ISSN) ; Delavari H., H ; Madaah Hosseini, H. R ; Sharif University of Technology
2011
Abstract
An analytical model is proposed to study the effect of particle size on melting enthalpy and entropy of metallic nanoparticles (NPs). The Mott's and Regel's equations for melting entropy in the combination of core average coordination number (CAC) and surface average coordination number (SAC) of freestanding NPs are considered. Clusters of icosahedral (IC), body centered cubic (BCC), and body centered tetragonal (BCT) structure without any vacancies and defects are modeled. Using the variable coordination number made this model to be in good agreement with experimental and molecular dynamic (MD) results of different crystal structures. The model predicts melting entropy and enthalpy of...
On the temperature and residual stress field during grinding
, Article WCE 2010 - World Congress on Engineering 2010, 30 June 2010 through 2 July 2010 ; Volume 2 , 2010 , Pages 1196-1200 ; 9789881821072 (ISBN) ; Farrahi, G. H ; Ghadbeigi, H ; Sharif University of Technology
2010
Abstract
Grinding is widely used for manufacturing of components that require fine surface finish and good dimensional accuracy. In this study a thermo-mechanical finite element analysis is conducted to find out how grinding parameters can affect temperature and residual stress distribution in the workpiece. Results of parametric study presented in this work indicate, by carefully selecting the grinding parameters, minimum thermal and mechanical damage can be achieved. Higher workpiece velocities produce higher surface residual stress. By increasing depths of cut, depth of tensile residual stresses increases. Convection heat coefficient does not have any considerable effect on surface residual stress...
A new lattic LP-based post filter for adaptive noise cancellers in mobile and vehicular applications
, Article Proceedings of the 8th IEEE International Symposium on Signal Processing and Information Technology, ISSPIT 2008, 16 December 2008 through 19 December 2008, Sarajevo ; 2008 , Pages 407-412 ; 9781424435555 (ISBN) ; Sameti, H ; Veisi, H ; Abutalebi, H. R ; Sharif University of Technology
2008
Abstract
Adaptive Noise Cancellation (ANC) is a well-known technique for background noise reduction in automobile and vehicular environments. The noise fields in automobile and other vehicle interior obey the diffuse noise field model closely. On the other hand, the ANC does not provide sufficient noise reduction in the diffuse noise fields. In this paper, a new multistage post-filter is designed for ANC as a solution to diffuse noise conditions. The designed post-filter is a single channel Linear Prediction (LP) based speech enhancement system. The LP is performed by an adaptive lattice filter and attempts to extract speech components by using intermediate ANC signals. The post-filter has no...
Advancing Compressive Strength Prediction in Self-Compacting Concrete via Soft Computing: A Robust Modeling Approach
, Article Journal of Soft Computing in Civil Engineering ; Volume 8, Issue 1 , 2024 , Pages 126-140 ; 25882872 (ISSN) ; Maleki, H ; Naderpour, H ; Khatami, M. H ; Sharif University of Technology
2024
Abstract
Self-Compacting Concrete (SCC) is a unique type of concrete that can flow and fill spaces without the need for vibrating compaction, resulting in a dense and uniform material. This article focuses on estimating the compressive strength of SCC utilizing Artificial Neural Networks. Specifically, the study employs multilayer perceptrons with back-propagation learning algorithms, which are commonly used in various problem-solving scenarios. The study covers essential components such as structure, algorithm, data preprocessing, over-fitting prevention, and sensitivity analysis in MLPs. The input variables considered in the research include water, fine aggregate, super-plasticizer, fly ash, coarse...