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A multi sender attribute-based broadcast authentication scheme
, Article 2016 8th International Symposium on Telecommunications, IST 2016, 27 September 2016 through 29 September 2016 ; 2017 , Pages 78-83 ; 9781509034345 (ISBN) ; Ameri, M. H ; Mohajeri, J ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Multi sender attribute-based broadcast authentication scheme for the network containing resource constrained nodes is the main focus of this research. In this paper, we proposed a framework in which each element of a set of authorized users whose attributes satisfy a special sign control policy can generate a valid signature. In this framework, there exists a trusted server who receives and verifies the validity of the generated attribute-based signatures and broadcast the intended message through the nodes of the network in an efficient and authenticated manner. We also proposed a new symmetric-based broadcast authentication scheme which is used for broadcasting the authenticated messages...
Access control enforcement on outsourced data ensuring privacy of access control policies
, Article Proceedings of the 2011 International Conference on High Performance Computing and Simulation, HPCS 2011, 4 July 2011 through 8 July 2011, Istanbul ; 2011 , Pages 491-497 ; 9781612843810 (ISBN) ; Hadavi, M. A ; Jalili, R ; Sharif University of Technology
2011
Abstract
Nowadays, data outsourcing has become a solution for many organizations especially large scale enterprises due to the high costs of in-house management of the rapidly growing data. Among all security requirements in this context, user access control and its following dynamic changes are of interest. In this paper, we propose an efficient and reliable mechanism to solve this problem in owner-write-users-read applications. A novel solution is introduced to enforce access control on outsourced data using the Chinese Remainder Theorem. The solution allows updating policy changes at a limited cost in terms of both computational power and the number of users' secret keys. Although the server, on...
Integrated analysis of energy-pollution-health nexus for sustainable energy planning
, Article Journal of Cleaner Production ; Volume 356 , 2022 ; 09596526 (ISSN) ; Alizadeh, S ; Avami, A ; Kianbakhsh, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In recent years, the emission of various pollutants has caused many problems for human life and the ecosystem. The prioritization between different air pollution control scenarios is a challenge between scientists and policy-makers. This study develops an integrated method for sustainable energy planning considering the energy-pollution-health nexus. The paper investigates three main pollutants (i.e., PM2.5, SO2, and NOx) of different emission sources (i.e., industrial, residential, and intra-city and suburban transportations) in twelve scenarios. The American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) is applied to model the air pollution dispersion,...
Access control aware data retrieval for secret sharing based database outsourcing
, Article Distributed and Parallel Databases ; Volume 34, Issue 4 , Dec , 2015 , pp 505–534 ; 09268782 (ISSN) ; Jalili, R ; Karimi, L ; Sharif University of Technology
Kluwer Academic Publishers
2015
Abstract
Enforcing dynamic and confidential access control policies is a challenging issue of data outsourcing to external servers due to the lack of trust towards the servers. In this paper, we propose a scalable yet flexible access control enforcement mechanism when the underlying relational data, on which access policies are defined, has been shared through a secret sharing scheme. For sharing values of an attribute in a relation, the attribute is assigned a secret distribution key and its values are split and distributed among data servers according to a Shamir based secret sharing scheme. Given access control policies over attributes of the relation schema, access to distribution keys, used...
Access control aware data retrieval for secret sharing based database outsourcing
, Article Distributed and Parallel Databases ; Volume 34, Issue 4 , 2016 , Pages 505-534 ; 09268782 (ISSN) ; Jalili, R ; Karimi, L ; Sharif University of Technology
Springer New York LLC
2016
Abstract
Enforcing dynamic and confidential access control policies is a challenging issue of data outsourcing to external servers due to the lack of trust towards the servers. In this paper, we propose a scalable yet flexible access control enforcement mechanism when the underlying relational data, on which access policies are defined, has been shared through a secret sharing scheme. For sharing values of an attribute in a relation, the attribute is assigned a secret distribution key and its values are split and distributed among data servers according to a Shamir based secret sharing scheme. Given access control policies over attributes of the relation schema, access to distribution keys, used...
Transmit power reduction by adapting rate or power for single carrier wireless systems
, Article 25th IEEE International Performance, Computing, and Communications Conference, 2006, IPCCC 2006, Phoenix, AZ, 10 April 2006 through 12 April 2006 ; Volume 2006 , 2006 , Pages 103-109 ; 1424401976 (ISBN); 9781424401970 (ISBN) ; Pakravan, M. R ; Khalaj, B. H ; Sharif University of Technology
2006
Abstract
Adaptive modulation with the goal of minimizing the average transmit power is investigated. This is the dual problem of the well-known problem of maximizing the average spectral efficiency. This is desirable in power limited systems such as mobile and sensor networks. Two main cases are considered: adapting only transmit power and adapting only rate. Appropriate expressions for rate or power control policies are derived for different cases. For rate adaptation, we consider both continuous and discrete rate policies. Then, we will apply these methods to a special case of M-QAM modulation over Rayleigh fading channel. We will show that by using rate or power adaptation schemes, between 7dB and...
Context-aware provisional access control
, Article 2nd International Conference on Information Systems Security, ICISS 2006, 19 December 2006 through 21 December 2006 ; Volume 4332 LNCS , 2006 , Pages 132-146 ; 03029743 (ISSN); 9783540689621 (ISBN) ; Amini, M ; Jalili, R ; Sharif University of Technology
Springer Verlag
2006
Abstract
High heterogeneity and dynamicity of pervasive computing environments introduces requirement of more flexible and functional access control policies. The notion of provisional actions has been defined previously to overcome the insufficient grant/denial response to an access request and has been incorporated in the provision-based access controlmodel(PBAC).BasedonPBAC,weproposeacontext-aware provision-based access control model, capable of dynamic adaptation of access control policy according to the changing context. In particular, the model facilitates the definition of context-aware policies and enriches the access control by enforcing provisional actions in addition to common permissions....
Stable handspring maneuvers with passive flight phases: Results from an inverted pendulum-like template
, Article International Journal of Non-Linear Mechanics ; Volume 128 , 2021 ; 00207462 (ISSN) ; Nouriani, A ; Alasty, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Inverted pendulum (IP) has been broadly used to model locomotor systems. In this paper, we demonstrate that an IP-like model could simulate stable periodic handspring maneuvers with passive flight phases. The model is a 2-D symmetric rigid body which is merely controlled during the contact phase. To benefit from an open-loop sensorless strategy, the control policy is implemented only by an unvaried torque input. The system's dynamics is an example of nonlinear impulsive systems studied and analyzed by the Poincaré section method. The numerical results reveal that the stable periodic solutions are sufficiently robust for a broad range of the parameter space. © 2020 Elsevier Ltd
Collaborative privacy management in P2P online social networks
, Article 12th International ISC Conference on Information Security and Cryptology, 8 September 2015 through 10 September 2015 ; 2015 , Pages 64-72 ; 9781467376099 (ISBN) ; Alizadeh, M ; Abbas Pour, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
Online Social Networks (OSNs) have become widely popular in recent years. In spite of users' interest to join OSNs, sharing vast amounts of personal information and resources in these networks might result in privacy issues for them. In the centralized OSNs, access control policies defined by users are enforced by OSN providers. Moreover, as these shared resources are stored by providers, they can access them. To avoid such problems, various architectures for decentralized OSNs are proposed. But the proposed architectures for P2P OSNs yet do not support any mechanism for collaborative privacy management on the shared content. By increasing the amount of resources such as photos which is...
Nonlinear optimal control of planar musculoskeletal arm model with minimum muscles stress criterion
, Article Journal of Computational and Nonlinear Dynamics ; Volume 12, Issue 1 , 2017 ; 15551415 (ISSN) ; Salarieh, H ; Behzadipour, S ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2017
Abstract
In this paper, the optimal performance of a planar humanlike musculoskeletal arm is investigated during reaching movements employing an optimal control policy. The initial and final states (position and velocity) are the only known data of the response trajectory. Two biomechanical objective functions are taken into account to be minimized as the central nervous system (CNS) strategy: (1) a quadratic function of muscle stresses (or forces), (2) total time of movement plus a quadratic function of muscle stresses. A two-degress of freedom (DOF) nonlinear musculoskeletal arm model (for planar movements) with six muscle actuators and four state variables is used in order to evaluate the proposed...
Enforcing access control policies over data stored on untrusted server
, 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 54-57 ; 9781538665602 (ISBN) ; Jalili, R ; Sharif University of Technology
Abstract
One of the security issues in data outsourcing scenario is the enforcement of data owner's access control policies. This includes some challenges; namely, the number of keys required to access authorized resources, efficient policy updating, write access control enforcement, user and data owner overhead, and preserving confidentiality of data and policies. Most of the existing solutions address only some of the challenges, while they impose high overhead on both the data owner and users. Though, policy management in the Role-Based Access Control (RBAC) model is easier and more efficient due to the existence of role hierarchical structure and role inheritance; most of the existing solutions...
Attribute-based fine-grained access control for outscored private set intersection computation
, Article Information Sciences ; Volume 536 , 2020 , Pages 222-243 ; Mohajeri, J ; Sadeghi, M. R ; Liu, X ; Sharif University of Technology
Elsevier Inc
2020
Abstract
Private set intersection (PSI) is a fundamental cryptographic protocol which has a wide range of applications. It enables two clients to compute the intersection of their private datasets without revealing non-matching elements. The advent of cloud computing drives the ambition to reduce computation and data management overhead by outsourcing such computations. However, since the cloud is not trustworthy, some cryptographic methods should be applied to maintain the confidentiality of datasets. But, in doing so, data owners may be excluded from access control on their outsourced datasets. Therefore, to control access rights and to interact with authorized users, they have to be online during...
A framework for protecting privacy on mobile social networks
, Article Mobile Networks and Applications ; Volume 26, Issue 3 , 2021 , Pages 1281-1299 ; 1383469X (ISSN) ; Movaghar, A ; Safikhani Mahmoodzadeh, K ; Sharif University of Technology
Springer
2021
Abstract
In recent years, mobile social networks have largely been developed and gained considerable popularity. An approach to protecting privacy on mobile social networks is the use of encryption and access control. Good alternatives for use on mobile social networks are the Public Broadcast Encryption approach for appropriate concordance and consistency with the structure of social networks as well as the Attribute-Based Encryption owing to its capability and proper implementation of the access control policy. Accordingly, in this paper, a framework was presented based on the Public Broadcast Encryption and Attribute-Based Encryption. Using proxies, we outsourced some of these operations in the...
Policy specification and enforcement in online social networks using MKNF+
, Article 2012 9th International ISC Conference on Information Security and Cryptology, ISCISC 2012, 13 September 2012 through 14 September 2012 ; 2012 , Pages 48-53 ; 9781467323864 (ISBN) ; Javadi, S. A ; Amini, M ; Jalili, R ; Sharif University of Technology
2012
Abstract
Emerging tools that ease sharing information in online social networks (OSNs) can cause various privacy issues for users. Access control is the main security mechanism in OSNs which is used to tackle such issues. In this paper, a prioritized ontology based access control model for protecting users' information in OSNs is proposed. In the proposed model, description logic (DL) is used for modeling social networks and MKNF+ rules are used for specification of users' access control policies. Using MKNF+, we can have nonmonotonic inference (i.e., closed-world reasoning) in the access control procedure. Conflict among access rules defined by a user in an OSN, is another problem, which is resolved...
Modeling (r, Q) policy in a two-level supply chain system with fuzzy demand
, Article International Journal of Uncertainty, Fuzziness and Knowlege-Based Systems ; Volume 18, Issue 6 , 2010 , Pages 819-841 ; 02184885 (ISSN) ; Modarres Yazdi, M ; Sharif University of Technology
2010
Abstract
In this paper a two level supply chain system is studied, in which the final demand is assumed to be fuzzy with triangular membership function. The inventory control policy of (r, Q) is followed for this system and unsatisfied demand is assumed to be back ordered. The objective is to minimize the total cost of the system, including ordering, holding and shortage costs. The model happens to be a nonlinear programming. Considering the complexity arising from the model, we also develop a genetic algorithm to obtain a near-optimal solution. The method is illustrated through some numerical examples
GTHBAC: A generalized temporal history based access control model
, Article Telecommunication Systems ; Volume 45, Issue 2-3 , 2010 , Pages 111-125 ; 10184864 (ISSN) ; Haadi Jafarian, J ; Amini, M ; Jalili, R ; Sharif University of Technology
Abstract
Time plays a crucial role in access control for new computing environments, which is not supported in traditional access control models. In this paper, we propose a Generalized Temporal History Based Access Control (GTHBAC) model, aimed at integrating history-based constraints along with a generic access control model. GTHBAC enhances the specification of user-defined authorization rules by constraining time interval and temporal expression over users' history of accesses. Due to different application needs, GTHBAC uses two different time schemes, i.e., real time and logical time, in its authorization rules. A formal semantics for temporal authorizations is provided, and conflicting...
Introducing a new ordering policy in a two-echelon inventory system with Poisson demand
, Article International Journal of Production Economics ; Volume 117, Issue 1 , 2009 , Pages 212-218 ; 09255273 (ISSN) ; Neghab, M. P ; Baboli, A
Elsevier
2009
Abstract
In this paper we introduce a new ordering policy for inventory control in a two-echelon inventory system consisting of one central warehouse and a number of non-identical retailers. The warehouse uses a modified one-for-one policy, but the retailers apply a new policy which is different from the traditional inventory policies described in the literature of inventory and production control systems. In this system, each retailer constantly places an order for one unit of product to the central warehouse in a pre-determined time interval; i.e., the time interval between any two consecutive orders from each retailer is a fixed number and the quantity of each order is one. We then show how the...
A context-aware mandatory access control model for multilevel security environments
, Article 27th International Conference on Computer Safety, Reliability, and Security, SAFECOMP 2008, Newcastle upon Tyne, 22 September 2008 through 25 September 2008 ; Volume 5219 LNCS , 2008 , Pages 401-414 ; 03029743 (ISSN); 3540876979 (ISBN); 9783540876977 (ISBN) ; Amini, M ; Jalili, R ; Sharif University of Technology
2008
Abstract
Mandatory access control models have traditionally been employed as a robust security mechanism in multilevel security environments like military domains. In traditional mandatory models, the security classes associated with entities are context-insensitive. However, context-sensitivity of security classes may be required in some environments. Moreover, as computing technology becomes more pervasive, flexible access control mechanisms are needed. Unlike traditional approaches for access control, such access decisions depend on the combination of the required credentials of users and the context of the system. Incorporating context-awareness into mandatory access control models results in a...
Enhancing role-based access control model through fuzzy relations
, Article 3rd Internationl Symposium on Information Assurance and Security, IAS 2007, Manchester, 20 August 2007 through 31 August 2007 ; September , 2007 , Pages 131-136 ; 0769528767 (ISBN); 9780769528762 (ISBN) ; Amini, M ; Jalili, R ; Sharif University of Technology
2007
Abstract
Role-Based Access Control (RBAC) model is naturally suitable to organizations where users are assigned organizational roles with well-defined privileges. However, due to the large number of users in nowadays online services of organizations and enterprises, assigning users to roles is a tiresome task and maintaining user-role assignment up- to-date is costly and error-prone. Additionally, with the increasing number of users, RBAC may have problems in prohibiting cheat and changing roles of users. In order to categorize information and formulate security policies, human decision making is required which is naturally fuzzy in the real world. This leads using a fuzzy approach to address the...
An energy-efficient controller for wirelessly-powered communication networks
, Article IEEE Transactions on Communications ; Volume 68, Issue 8 , August , 2020 , Pages 4986-5002 ; Makki, B ; Omidvar, N ; Pakravan, M. R ; Svensson, T ; Zorzi, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
In a wirelessly-powered communication network (WPCN), an energy access point (E-AP) supplies the energy needs of the network nodes through radio frequency wave transmission, and the nodes store their received energy in their batteries for possible data transmission. In this paper, we propose an online control policy for energy transfer from the E-AP to the wireless nodes and for data transfer among the nodes. With our proposed control policy, all data queues of the nodes are stable, while the average energy consumption of the network is shown to be within a bounded gap of the minimum energy required for stabilizing the network. Our proposed policy is designed using a quadratic Lyapunov...