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Private Inner product retrieval for distributed machine learning
, Article 2019 IEEE International Symposium on Information Theory, ISIT 2019, 7 July 2019 through 12 July 2019 ; Volume 2019-July , 2019 , Pages 355-359 ; 21578095 (ISSN); 9781538692912 (ISBN) ; Maddah Ali, M. A ; Mirmohseni, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, we argue that in many basic algorithms for machine learning, including support vector machine (SVM) for classification, principal component analysis (PCA) for dimensionality reduction, and regression for dependency estimation, we need the inner products of the data samples, rather than the data samples themselves.Motivated by the above observation, we introduce the problem of private inner product retrieval for distributed machine learning, where we have a system including a database of some files, duplicated across some non-colluding servers. A user intends to retrieve a subset of specific size of the set of the inner product of every pair of data items in the database with...
Tiny graviton matrix theory/SYM correspondence: Analysis of BPS states
, Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 74, Issue 6 , 2006 ; 15507998 (ISSN) ; Sheikh Jabbari, M. M ; Torabian, M ; Sharif University of Technology
2006
Abstract
In this paper we continue analysis of the Matrix theory describing the DLCQ of type IIB string theory on AdS5×S5 (and/or the plane-wave) background, i.e. the tiny graviton matrix theory (TGMT). We study and classify 1/2, 1/4, and 1/8 BPS solutions of the TGMT which are generically of the form of rotating three-brane giants. These are branes whose shape are deformed three-spheres and hyperboloids. In lack of a classification of such ten-dimensional type IIb supergravity configurations, we focus on the dual N=4 four-dimensional 1/2, 1/4, and one 1/8 BPS operators and show that they are in one-to-one correspondence with the states of the same set of quantum numbers in TGMT. This provides...
Extensions of AdS5 × S5 and the plane-wave superalgebras and their realization in the tiny graviton matrix theory
, Article Journal of High Energy Physics ; Issue 3 , 2006 , Pages 4613-4636 ; 10298479 (ISSN) ; Sheikh Jabbari, M. M ; Torabian, M ; Sharif University of Technology
2006
Abstract
In this paper we consider all consistent extensions of the AdS5 × S5 superalgebra, psu(2,2/4), to incorporate brane charges by introducing both bosonic and fermionic (non)central extensions. We study the Inönü-Wigner contraction of the extended psu(2,2/4) under the Penrose limit to obtain the most general consistent extension of the plane-wave superalgebra and compare these extensions with the possible BPS (flat or spherical) brane configurations in the plane-wave background. We give an explicit realization of some of these extensions in terms of the Tiny Graviton Matrix Theory (TGMT) [14] which is the 0+1 dimensional gauge theory conjectured to describe the DLCQ of strings on the AdS5 × S5...
A new homologous series of linear aliphatic unsaturated hydroxypolyesters a polyol soft segments for polyurethanes: Synthesis and characterization [electronic resource]
, Article Journal of Applied Polymer Science ; Volume 68, Issue 2, pages 173–183, 11 April 1998 ; Rezai, Nasrin ; Zohurian, M. J ; Sharif University of Technology
Abstract
Synthesis and characterization of a new series of low molecular weight (MW = 500–3000) OH-terminated linear aliphatic unsaturated polyesters based on cis-2-butene-1,4-diol and oxalic to sebacic acid were investigated. Direct polycondensation and transesterification methods were used for the syntheses. The latter was recognized to be the preferable method due to its lower reaction temperature and time, lower diol/diacid ratio, absence of decarboxylation, and formation of a product with low polydispersity (Mw/Mn = 1.3–2.7). Elemental analysis, GPC, FTIR, 1H-NMR, DSC, and WAXD were used for the investigations. A segmented polyurethane based on poly (cis-2-butylene adipate) glycol was also...
Optimal DR through HVAC loads in distribution systems hosting large wind generation
, Article IEEE Innovative Smart Grid Technologies, 3 November 2015 through 6 November 2015 ; 2015 ; 9781509012381 (ISBN) ; Humayun, M ; Degefa, M ; Lehtonen, M ; Safdarain, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
The penetration of wind generation in distribution networks is steadily increasing and may provide ample business opportunities for aggregators. While, residential demand response (DR) has proven to be a feasible economic tool in smart grids, the quantitative evaluation of various aggregator-based DR services is required to tap the maximum benefits from the DR flexibility. This paper provides an overview of benefits of different DR aggregator services such as minimization of energy cost and wind curtailment given the scenario of large wind generation hosted by distribution network. An optimization model is formulated from aggregator perspective to manage the population of heating,...
Increased utilization of wind generation by coordinating the demand response and real-time thermal rating
, Article IEEE Transactions on Power Systems ; Volume 31, Issue 5 , 2016 , Pages 3737-3746 ; 08858950 (ISSN) ; Zenebe Degefa, M ; Humayun, M ; Safdarian, A ; Lehtonen, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Demand response (DR) will play an essential role in smart grids by contributing to the operational flexibility requirement arising from the increased penetration of intermittent renewable generation. However, DR activation could be hampered in the absence of intelligent network management. Real-time thermal rating (RTTR) functions as a smart network management tool for unlocking the network capacities by allowing the network to safely operate during overload states. This paper offers an optimal residential DR approach integrated with RTTR to balance the hourly wind power production. The proposed framework is modeled from the perspective of an electrical aggregator that manages the population...
Domestic EWH and HVAC management in smart grids: Potential benefits and realization
, Article Electric Power Systems Research ; Volume 134 , 2016 , Pages 38-46 ; 03787796 (ISSN) ; Mubbashir, Ali ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
Demand response is envisioned as a key solution to increase network efficiency as well as to alleviate challenges such as growing demand. In this paper, domestic electric water heater (EWH) and heating, ventilation, and air-conditioning (HVAC) are considered for potential demand response applications. An interaction between the system operator and consumers is considered to facilitate managing cyclic operation of consumers' heating loads. A centralized control model is first developed and formulated to achieve potential benefits of demand response of EWH and HVAC loads. Then, a distributed control algorithm is designed for practical implementation. In the proposed algorithm, house-wide...
A two-layer attack-robust protocol for IoT healthcare security: Two-stage identification-authentication protocol for IoT
, Article IET Communications ; Volume 15, Issue 19 , 2021 , Pages 2390-2406 ; 17518628 (ISSN) ; Sepideh, A ; Ali, M ; Salah, A. M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
The majority of studies in the field of developing identification and authentication protocols for Internet of Things (IoT) used cryptographic algorithms. Using brain signals is also a relatively new approach in this field. EEG signal-based authentication algorithms typically use feature extraction algorithms that require high processing time. On the other hand, the dynamic nature of the EEG signal makes its use for identification/authentication difficult without relying on feature extraction. This paper presents an EEG-and fingerprint-based two-stage identification-authentication protocol for remote healthcare, which is fast, robust, and multilayer-based. A modified Euclidean distance...
The relaxed three-algebras: their matrix representation and implications for multi M2-brane theory
, Article Journal of High Energy Physics ; Volume 2008, Issue 12 , 2008 ; 11266708 (ISSN) ; Sheikh Jabbari, M. M ; Simon, J ; Sharif University of Technology
2008
Abstract
We argue that one can relax the requirements of the non-associative three-algebras recently used in constructing D = 3, = 8 superconformal field theories, and introduce the notion of ''relaxed three-algebras''. We present a specific realization of the relaxed three-algebras in terms of classical Lie algebras with a matrix representation, endowed with a non-associative four-bracket structure which is prescribed to replace the three-brackets of the three-algebras. We show that both the so(4)-based solutions as well as the cases with non-positive definite metric find a uniform description in our setting. We discuss the implications of our four-bracket representation for the D = 3, = 8 and multi...
Numerical simulation of viscous dissipation in a micropolar fluid flow through a porous medium
, Article Journal of Applied Mechanics and Technical Physics ; Volume 60, Issue 6 , 2019 , Pages 996-1004 ; 00218944 (ISSN) ; Ashraf, M ; Ali, K ; Sharif University of Technology]
Pleiades Publishing
2019
Abstract
Taking into account the effect of viscous dissipation in the energy equation, we numerically explore the flow of an incompressible micropolar fluid with heat and mass transfer through a resistive porous medium between plane channel walls. By exploiting a similarity transformation, the governing partial differential equations are transformed into a system of nonlinear coupled ordinary differential equations, which are solved numerically for various problem parameters by means of quasi-linearization. It is found that the effect of viscous dissipation is to increase the heat and mass transfer rate at both the lower and upper walls of the channel. © 2019, Pleiades Publishing, Ltd
Private sequential function computation
, Article 2019 IEEE International Symposium on Information Theory, ISIT 2019, 7 July 2019 through 12 July 2019 ; Volume 2019-July , 2019 , Pages 1667-1671 ; 21578095 (ISSN); 9781538692912 (ISBN) ; Maddah Ali, M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, we introduce the problem of private sequential function computation, where a user wishes to compute a composition of a sequence of K linear functions, in a specific order, for an arbitrary input. The user does not run these computations locally, rather it exploits the existence of N non-colluding servers, each can compute any of the K functions on any given input. However, the user does not want to reveal any information about the desired order of computations to the servers. For this problem, we study the capacity, defined as the supremum of the number of desired computations, normalized by the number of computations done at the servers, subject to the privacy constraint. In...
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, Article 2018 Iran Workshop on Communication and Information Theory, IWCIT 2018, 25 April 2018 through 26 April 2018 ; 2018 , Pages 1-6 ; 9781538641491 (ISBN) ; Maddah Ali, M. A ; Sharif University of Technology
Institute of electrical and electronics engineers Inc
2018
Abstract
The widespread use of cloud computing services raises the question of how one can delegate the processing tasks to the untrusted distributed parties without breaching the privacy of its data and algorithms. Motivated by the algorithm privacy concerns in a distributed computing system, in this paper, we introduce the private function retrieval (PFR) problem, where a user wishes to efficiently retrieve a linear function of K messages from N non-communicating replicated servers while keeping the function hidden from each individual server. The goal is to find a scheme with minimum communication cost. To characterize the fundamental limits of the communication cost, we define the capacity of PFR...
Simulation of thermal radiation in a micropolar fluid flow through a porous medium between channel walls
, Article Journal of Thermal Analysis and Calorimetry ; Volume 144, Issue 3 , 2021 , Pages 941-953 ; 13886150 (ISSN) ; Ashraf, M ; Ali, K ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Among numerous methods which have been employed to reinforce the thermal efficiency in many systems, one is the thermal radiation which is a mode of heat transfer. Another way to improve the thermal efficiency is the utilization of the porous media. The present work includes the study of micropolar flow with allowance for thermal radiation through a resistive porous medium between channel walls. The governing coupled partial differential equations representing the flow model are transmuted into ordinary ones by using the suitable dimensionless coordinates, and then, quasi-linearization is employed to solve the set of relevant coupled ODEs. Effects of physical parameters on the flow under...
Simulation of thermal radiation in a micropolar fluid flow through a porous medium between channel walls
, Article Journal of Thermal Analysis and Calorimetry ; Volume 144, Issue 3 , 2021 , Pages 941-953 ; 13886150 (ISSN) ; Ashraf, M ; Ali, K ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Among numerous methods which have been employed to reinforce the thermal efficiency in many systems, one is the thermal radiation which is a mode of heat transfer. Another way to improve the thermal efficiency is the utilization of the porous media. The present work includes the study of micropolar flow with allowance for thermal radiation through a resistive porous medium between channel walls. The governing coupled partial differential equations representing the flow model are transmuted into ordinary ones by using the suitable dimensionless coordinates, and then, quasi-linearization is employed to solve the set of relevant coupled ODEs. Effects of physical parameters on the flow under...
A framework for activating residential HVAC demand response for wind generation balancing
, Article IEEE Innovative Smart Grid Technologies, 3 November 2015 through 6 November 2015 ; 2015 ; 9781509012381 (ISBN) ; Humayun, M ; Degefa, M ; Alahaivala, A ; Lehtonen, M ; Safdarian, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
The integration of a great deal of intermittent renewable generation in future grids will require more operational flexibility. Residential demand response can provide the load shaping potentials thereby alleviating the need for operational flexibility. This paper intends to develop a centralized framework focusing on realization of domestic heating, ventilation, and air conditioning (HVAC) demand response capability for wind power balancing. In the proposed optimization model, energy consumption of HVAC loads is optimized to tackle the variability of wind power. The thermal comfort penalty is explicitly integrated in the objective function in order to oblige different customers' thermal...
Employing humanoid robots for teaching english language in Iranian junior high-schools [electronic resource]
, Article International Journal of Humanoid Robotics ; Vol. 11, No. 3 (2014) 1450022 ; Meghdari, Ali ; Ghazisaedy, Maryam ; Sharif University of Technology
Abstract
This paper presents the effect of robotics assisted language learning (RALL) on the vocabulary learning and retention of Iranian English as foreign language (EFL) junior high school students in Tehran, Iran. After taking a vocabulary pre-test, 46 beginner level female students at the age of 12, studying in their first year of junior-high participated in two groups of RALL (30 students) and non-RALL (16 students) in this study. The textbook used was the English book (Prospect-1) devised by the Iranian Ministry of Education for 7th graders, and the vocabulary taught and tested (pre-test and post-test) were taken from this book. Moreover, the treatment given by a teacher accompanied by a...
Modified carrageenan. 5. Preparation, swelling behavior, salt- and pH-sensitivity of partially hydrolyzed crosslinked carrageenan-graft-polymethacrylamide superabsorbent hydrogel [electronic resource]
, Article Polymers for Advanced Technologies ; Volume 15, Issue 11, pages 645–653, November 2004 ; Sadeghi, M ; Hosseinzadeh, H
Abstract
The polysaccharide, kappa-carrageenan (κC) was chemically modified to achieve a novel superabsorbent hydrogel via graft copolymerization of methacrylamide (MAM) onto the substrate followed by alkaline hydrolysis. Ammonium persulfate (APS) and N,N′-methylene bisacrylamide (MBA) were used as a free-radical initiator and a crosslinker, respectively. The saponification reaction was carried out using sodium hydroxide aqueous solution. Either κC-g-PMAM or hydrolyzed κC-g-PMAM (PMAM: polymethacrylamide) was characterized by FT-IR spectroscopy. The effect of grafting variables (i.e. concentration of MBA, MAM, and APS) and alkaline hydrolysis conditions (i.e. NaOH concentration, hydrolysis time and...
Electrocatalytic CO2 fixation by regenerating reduced cofactor NADH during calvin cycle using glassy carbon electrode
, Article PLoS ONE ; Volume 15, Issue 9 September , 2020 ; Amiri, S ; Ullah, N ; Younas, M ; Rezakazemi, M ; Sharif University of Technology
Public Library of Science
2020
Abstract
In this study, an enzymatic pathway has been developed to replicate the Calvin Cycle by creating the individual steps of the carbon cycle in a bioreactor. The technology known as “artificial photosynthesis” converts CO2 emissions into a variety of intermediates that serve as precursors to high-value products. CO2, light, water, and electricity were used as feedstock. An electrochemical reactor was also studied for the regeneration of active NADH operating at constant electrode potential. Initially, a batch electrochemical reactor containing 80 mL of 0.2 mM NAD+ in Tris-buffer (pH 7.40) was used to evaluate the electrode material operating at normal temperature and pressure. The results...
Multi-message private information retrieval with private side information
, Article 2018 IEEE Information Theory Workshop, ITW 2018, 25 November 2018 through 29 November 2018 ; 2019 ; 9781538635995 (ISBN) ; Jafari Siavoshani, M ; Maddah Ali, M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
We consider the problem of private information retrieval (PIR) where a single user with private side information aims to retrieve multiple files from a library stored (uncoded) at a number of servers. We assume the side information at the user includes a subset of files stored privately (i.e., the server does not know the indices of these files). In addition, we require that the identity of requests and side information at the user are not revealed to any of the servers. The problem involves finding the minimum load to be transmitted from the servers to the user such that the requested files can be decoded with the help of received and side information. By providing matching lower and upper...
Private Information Retrieval for a Multi-Message Scenario with Private Side Information
, Article IEEE Transactions on Communications ; Volume 69, Issue 5 , 2021 , Pages 3235-3244 ; 00906778 (ISSN) ; Shariatpanahi, S. P ; Maddah Ali, M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
We consider the problem of private information retrieval (PIR), where a single user with private side information (PSI) aims to retrieve multiple files from a library stored at some servers. We assume that the side information (SI) at the user includes a subset of files stored privately. Moreover, the identity of requests and side information at the user are not revealed to any of the servers. The problem involves finding the minimum load transmitted from the servers to the user such that the requested files can be decoded with the help of received data and side information. By providing matching lower and upper bounds for certain regimes, we characterize the minimum load imposed on all the...