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cybernetics
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Computer Simulation of Ultrasonic Waves in Cybernetic Glasses in Order to Increasing Spatial Resolution of Blinds
, M.Sc. Thesis Sharif University of Technology ; Amjadi, Ahmad (Supervisor)
Abstract
Eyesight is one of the most important tools for humans to communicate with environment and consequently, blindness or poor eyesight results in unsatisfactory effect on life quality. Owing to the importance of the sense and to assist to the patients, this thesis aims to design and assemble cybernetic glasses using ultrasound waves. To this end, firstly, the notion of waves focusing on ultrasound waves is described and reactions of human hearing system to the waves are studied. Then, the transducers as a key device are introduced. Afterward, bat sense system to communicate with environment which is based ultrasound waves is described. Next, attenuation effects on ultrasound wave pressures are...
Continuous neural network with windowed Hebbian learning
, Article Biological Cybernetics ; Volume 109, Issue 3 , June , 2015 , Pages 321-332 ; 03401200 (ISSN) ; Heidari, M ; Sharifitabar, M ; Sharif University of Technology
Springer Verlag
2015
Abstract
We introduce an extension of the classical neural field equation where the dynamics of the synaptic kernel satisfies the standard Hebbian type of learning (synaptic plasticity). Here, a continuous network in which changes in the weight kernel occurs in a specified time window is considered. A novelty of this model is that it admits synaptic weight decrease as well as the usual weight increase resulting from correlated activity. The resulting equation leads to a delay-type rate model for which the existence and stability of solutions such as the rest state, bumps, and traveling fronts are investigated. Some relations between the length of the time window and the bump width is derived. In...
Partial scalability to ensure reliable dynamic reconfiguration
, Article Proceedings - IEEE 7th International Conference on Self-Adaptation and Self-Organizing Systems Workshops, SASOW 2013 ; Sept , 2014 , p. 83-88 ; Heydarnoori, A ; Sharif University of Technology
Abstract
In order to be adapted to changes in user requirements and/or the environment, many software systems need to run continuously while they evolve. Most current approaches for such dynamic reconfiguration assume that the evolved system will behave as expected and thus will be reliable if the reconfiguration is consistent. This assumption may not correspond to reality because the delivered quality estimated previously could vary due to parameter changes at runtime. To ensure that the system acts correctly in the field after the reconfiguration, reliability of changes has to be checked at runtime. Existing approaches, however, are not applicable in highly available systems due to the possibility...
A new achievable rate and the capacity of a class of semi-deterministic relay networks
, Article 2007 IEEE International Symposium on Information Theory, ISIT 2007, Nice, 24 June 2007 through 29 June 2007 ; 2007 , Pages 281-285 ; 21578101 (ISSN) ; 1424414296 (ISBN); 9781424414291 (ISBN) ; Aref, M. R ; Sharif University of Technology
2007
Abstract
In this paper, we propose an information-theoretic constructive scheme based on generalized block Markov encoding strategy for obtaining an achievable rate for multirelay networks. The coding scheme is based on partial decoding scheme where the relay decodes only part of the transmitted message. The proposed achievable rate is then used to establish the capacity of a class of semi-deterministic relay networks composed of semi-deterministic relay channels. It is shown that the proposed rate will include those of previously proposed rates based on decode-and-forward strategy in some special cases. ©2007 IEEE
Synthetic Model Based in Viable System Model and System Dynamics for Analysis and Design of Systems
, M.Sc. Thesis Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
This is common for organizations to don't move in their specified mission statement direction, because of pressures for saving themselves in reaction to environment changes. This problem can be addressed as conflict between survival and identity. In this thesis we approach this problem by synthesizing "Viable System Model" and "System Dynamics". Basic of this model shaped on viable system model structure and system dynamics modeling. In literature there is only two such models. But they are not detailed enough for providing mathematical analysis. In this research, law of requisite variety (one of the key principles in cybernetics) has been quantified. In this synthetic model, appropriate...
Design and Optimization of a Cybernetics Hand
, M.Sc. Thesis Sharif University of Technology ; Sayyaadi, Hassan (Supervisor)
Abstract
In this study, we create an evolution function that assesses prosthetic hands in terms of their ability to grasp various objects like a human hand. It is required to evaluate the reachable workspace of prosthetic hands and grasp ability to assess it completely. The first one can be done by using forward kinematics. The Volume of the Grasp Wrench space, one of the grasp qualities indexes, is used to measure the second one. Randomization and grasp taxonomy are used to generalize the grasp quality to indicate the prosthetic hand functionality. Afterward, the created evaluation function is used to specify the importance of each finger and DOF. The results show that the most significant finger is...
Some notes on fix-free codes
, Article CISS 2008, 42nd Annual Conference on Information Sciences and Systems, Princeton, NJ, 19 March 2008 through 21 March 2008 ; 2008 , Pages 1015-1018 ; 9781424422470 (ISBN) ; Nazari, A ; Zadimoghaddam, M ; Sharif University of Technology
2008
Abstract
A variable-length code is called a fix-free code if it is both prefix-free and suffix-free. In this paper, we consider some basic properties of fix-free codes. We obtain one lower and one upper bound on the redundancy of the optimal fix-free code. Comparing these bounds, we derive an upper bound on the length of the most likely source symbol in terms of its probability. © 2008 IEEE
Finding sparse features for face detection using genetic algorithms
, Article ICCC 2008 - IEEE 6th International Conference on Computational Cybernetics, Stara Lesna, 27 November 2008 through 29 November 2008 ; 2008 , Pages 179-182 ; 9781424428755 (ISBN) ; Dehghani, M ; Enayati, E ; Sharif University of Technology
2008
Abstract
Although Face detection is not a recent activity in the field of image processing, it is still an open area for research. The greatest step in this field is the work reported by Viola and the recent analogous one is proposed by Huang et al. Both of them use similar features and also similar training process. The former is just for detecting upright faces, but the latter can detect multi-view faces in still grayscale images using new features called 'sparse feature'. Finding these features is very time consuming and inefficient by proposed methods. Here, we propose a new approach for finding sparse features using a genetic algorithm system. This method requires less computational cost and...
Achievable rates for two interfering broadcast channels with a cognitive transmitter
, Article 2008 IEEE International Symposium on Information Theory, ISIT 2008, Toronto, ON, 6 July 2008 through 11 July 2008 ; 2008 , Pages 1358-1362 ; 21578101 (ISSN) ; 9781424422579 (ISBN) ; Nasiri Kenari, M ; Sharif University of Technology
2008
Abstract
We introduce a new communication model consisting of two interfering broadcast channels with one cognitive transmitter, who knows the message transmitted by the other non-cognitive transmitter, in a non-causal manner. An achievable rate region is derived for this model. The region is computed based on the Marton region for the general broadcast channel and its extension by Steinberg to the broadcast channel with the states known at the transmitter. By using the region evaluated, an achievable rate for the Gaussian broadcast channel is derived. © 2008 IEEE
A new achievable rate for relay networks based on parallel relaying
, Article 2008 IEEE International Symposium on Information Theory, ISIT 2008, Toronto, ON, 6 July 2008 through 11 July 2008 ; 2008 , Pages 1328-1332 ; 21578101 (ISSN) ; 9781424422579 (ISBN) ; Aref, M. R ; Sharif University of Technology
2008
Abstract
In this paper, we propose a new concept of relaying named parallel relaying to obtain a new achievable rate for relay networks. The proposed encoding scheme is based on partial decoding, where the relay decodes only part of the transmitted message. The superiority of our proposed method to the previous ones is that, it can be applied to the relay networks with general structure, not necessarily with feed-forward structure. The proposed achievable rate is also used to establish the capacity of a class of semi-deterministic relay network which is a generalization of Aref network. © 2008 IEEE
Restoration of damaged slices in images using matrix pseudo inversion
, Article 22nd International Symposium on Computer and Information Sciences, ISCIS 2007, Ankara, 7 November 2007 through 9 November 2007 ; 2007 , Pages 98-103 ; 1424413648 (ISBN); 9781424413645 (ISBN) ; Manzuri Shalmani, M. T ; Lakdashti, A ; Sharif University of Technology
2007
Abstract
A matrix pseudo inversion based method is developed for coding of images in real field in a way that at the receiver, one can restore the lost portions of the images. The proposed solution is similar to channel coding techniques, but it is done before source coding at the transmitter and after decoding of the compressed data at the receiver. Experiments show the effectiveness of the proposed solution in recove ring missed portions of the images and video frames. ©2007 IEEE
A composition function model for software reconfiguration propagation in a network of systems
, Article 9th World Multi-Conference on Systemics, Cybernetics and Informatics, WMSCI 2005, Orlando, FL, 10 July 2005 through 13 July 2005 ; Volume 2 , 2005 , Pages 83-88 ; 980656054X (ISBN); 9789806560543 (ISBN) ; Niamanesh, M ; Jalili, R ; Sharif University of Technology
2005
Abstract
Reconfigurability in software has many advantages such as updating, bug fixing and adding new services. Dynamic reconfiguration is more useful for mission critical systems that need to change in run time. Reconfiguration of a system in network may result to reconfiguring its dependent systems, which we call reconfiguration propagation. In this paper, we present a model for reconfiguration propagation for systems in a network
Difference in assessment: Towards a dynamic assessment approach in education
, Article IMSCI 2011 - 5th International Multi-Conference on Society, Cybernetics and Informatics, Proceedings, 19 July 2011 through 22 July 2011, Orlando, FL ; Volume 2 , 2011 , Pages 59-64 ; 9781936338344 (ISBN) ; Sharif University of Technology
2011
Abstract
Discouraging the divorce between Language teaching and language testing, dynamic assessment has changed into a strong tool not only for language assessment but also for language development and leaner involvement in the learning process. This study aimed to investigate (a) Iranian EFL (English as a Foreign Language) learners' off-task self-assessment and on-task self-rating of their writing ability and the impact of a dynamic-assessment-based course on the accuracy of their self-assessment and self-rating, and (b) the interrelationships among teacher rating, self-assessment, and self-rating in the writing performance of 22 engineering students taking a writing course as part of an EAP...
A planar neuro-musculoskeletal arm model in post-stroke patients
, Article Biological Cybernetics ; Volume 112, Issue 5 , 2018 , Pages 483-494 ; 03401200 (ISSN) ; Behzadipour, S ; Taghizadeh, G ; Sharif University of Technology
Abstract
Mathematical modeling of the neuro-musculoskeletal system in healthy subjects has been pursued extensively. In post-stroke patients, however, such models are very primitive. Besides improving our general understanding of how stroke affects the limb motions, they can be used to evaluate rehabilitation strategies by computer simulations before clinical evaluations. A planar neuro-musculoskeletal arm model for post-stroke patients is developed. The main idea is to use a set of new coefficients, Muscle Significance Factors (MSF), to incorporate the effects of stroke in the muscle control performance. The model uses the optimal control theory to mimic the performance of the CNS and a two-link...
Coordination of large-scale systems using a new interaction prediction approach
, Article Proceedings of the Annual Southeastern Symposium on System Theory, 16 March 2008 through 18 March 2008, New Orleans, LA ; 2008 , Pages 385-389 ; 9781424418060 (ISBN) ; Ramezani, M. H ; Sharif University of Technology
2008
Abstract
In this paper, a new interaction prediction approach is presented for optimal control of nonlinear large-scale systems. The proposed approach uses a new gradient-type coordination scheme which has a larger convergence region with respect to the parameters' variation, and also has a good convergence rate. In this approach, the coordination vector is updated using the gradient of coordination error. This type of coordination considerably reduces the number of iterations. The robustness and the convergence rate of the proposed approach against the best classical interaction prediction approaches are shown through simulations of a benchmark problem. © 2008 IEEE
Generalized compress-and-forward strategy for relay networks
, Article 2008 IEEE International Symposium on Information Theory, ISIT 2008, Toronto, ON, 6 July 2008 through 11 July 2008 ; 2008 , Pages 2683-2687 ; 21578101 (ISSN) ; 9781424422579 (ISBN) ; Aref, M. R ; Sharif University of Technology
2008
Abstract
In this paper, we present a new generalization of the well-known Compress-and-Forward strategy for relay networks. We propose an offset decoding at destination, where destination considers an ordered partition of relays and decodes information of any partition with the help of information from prior partitions. We show that when we do not partition the set of relays, our result improves the result of Kramer, et al. A geometrical method is utilized to unify results of different ordered partitioning. Also, the unified result has a celebrated source-channel coding separation interpretation. © 2008 IEEE
Exergoeconomic Composite Curves-from theory to practice
, Article 11th World Multi-Conference on Systemics, Cybernetics and Informatics, WMSCI 2007, Jointly with the 13th International Conference on Information Systems Analysis and Synthesis, ISAS 2007, Orlando, FL, 8 July 2007 through 11 July 2007 ; Volume 5 , 2007 , Pages 332-337 ; 1934272191 (ISBN); 9781934272190 (ISBN) ; Farhanieh, B ; Mozafari, A. A ; International Institute of Informatics and Systemics (IIIS) ; Sharif University of Technology
2007
Abstract
Exergoeconomic Composite Curves (EECC) - a synergy of Exergoeconomic and Composite Curves of Pinch Analysis is a novel method and propounded for the first time in this Paper. This is the first attempt to represent investment and annual operating and maintenance costs in addition to Exergy in a graphical form similar to Composite Curves. In this Paper a simplified methodology that represents the Exergy of chemical units of a process in a graphical form and preliminary investment strategy is developed for use with the EECC. The object has therefore been to study the possibilities to save money in Northern Pulp and Paper Mill, an Iranian mill with a capacity of 600 tons/day
Leveled design of cryptography algorithms using cybernetic methods for using in telemedicine applications
, Article Computational Intelligence and Neuroscience ; Volume 2021 , 2021 ; 16875265 (ISSN) ; Aref, M. R ; Ramazani Khorshiddoust, R ; Sharif University of Technology
Hindawi Limited
2021
Abstract
The technology world is developing fast with the developments made in the hardware and software areas. Considering that privacy and security of telemedicine applications are among the main necessities of this industry, as a result, there is a need to use lightweight and practical algorithms to be used in applications in the field of telemedicine, while security have the least negative impact. The distinct and contradicting components in the design and implementation of the cryptography algorithm, to achieve various objectives in medicine-based applications, have made it a complicated system. It is natural that, without identifying the components, indices, and properties of each system...
A model to support context-aware service migration in pervasive computing environments
, Article 9th World Multi-Conference on Systemics, Cybernetics and Informatics, WMSCI 2005, Orlando, FL, 10 July 2005 through 13 July 2005 ; Volume 3 , 2005 , Pages 394-399 ; 9806560558 (ISBN); 9789806560550 (ISBN) ; Ranjbar, A ; Niamanesh, M ; Jalili, R ; Sharif University of Technology
2005
Abstract
Continuous improvement and extension of pervasive computing environments, in which objects have high mobility and limited computing power, implies service migration to be considered as one of the main issues. On the other hand, context-awareness which is the most distinguishable feature of pervasive computing helps better serving of users. Accordingly, migration in the presence of context-awareness is considered as the underlying of our motivation. This improves the performance of migration, which is not easily achievable through traditional migration techniques. In this paper we introduce a model to support context-aware migration besides its migration process phases and framework. Our...
Symmetric bursting behaviors in the generalized FitzHugh-Nagumo model
, Article Biological Cybernetics ; Volume 107, Issue 4 , 2013 , Pages 465-476 ; 03401200 (ISSN) ; Fallah, H ; Razvan, M. R ; Sharif University of Technology
2013
Abstract
In the current paper, we have investigated the generalized FitzHugh-Nagumo model. We have shown that symmetric bursting behaviors of different types could be observed in this model with an appropriate recovery term. A modified version of this system is used to construct bursting activities. Furthermore, we have shown some numerical examples of delayed Hopf bifurcation and canard phenomenon in the symmetric bursting of super-Hopf/homoclinic type near its super-Hopf and homoclinic bifurcations, respectively