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Modeling of the Flexible Instrument Inside the Vascular Environment for Its Motion Control in Minimally Invasive Procedures
, M.Sc. Thesis Sharif University of Technology ; Nejat Pishkenari, Hossein (Supervisor)
Abstract
Minimally invasive procedures are diagnostic or therapeutic methods that cause minimal injuries and side effects for patients. PCI is a common minimally invasive procedure for diagnosis and curing of cardiovascular disorders. In this procedure, the surgeon can have access to the cardiac vessels by a flexible instrument. However, motion control of this instrument inside the patient's body relies on surgeon's skills and in some cases, is time consuming so that the toxic effects of radiation on patient and surgical team increases. Magnetic flexible instruments are suggested to address this problem. Nevertheless, motion control of the flexible instrument inside the body still has many challenges...
Coding advantage decomposition inequality for the space-frequency block codes
, Article IET Communications ; Vol. 8, Issue. 4 , 2014 , Pages 500-507 ; ISSN: 17518628 ; Tofigh, S ; Mohammadian, Z ; Talebi, S ; Sharif University of Technology
Abstract
In this study, the authors present a new criterion which can be used to decompose the coding advantage (CA) of space-frequency block codes (SFBCs). The proposed decomposition separates the CA into two parts, called precoder-CA and channel-CA. The precoder-CA represents the effects of the precoder and the signal constellation, and can be used in the design of the precoder of SFBCs. The channel-CA, on the other hand, gives an indication of the effects of the channel characteristics, and can be utilised for optimising the permutation parameter. The authors have shown that the proposed decomposition method leads to a lower computational complexity for the optimisation procedure compared with the...
Design of dual- and quad-band E-CRLH-TLs with arbitrary phase characteristics
, Article Progress In Electromagnetics Research M ; Vol. 35, issue , 2014 , p. 141-149 ; Nikmehr, S ; Ghurt-Tappeh, M.V ; Bemani, M ; Sharif University of Technology
Abstract
In this paper, extended composite right/left-handed (E-CRLH) transmission line (TL) metamaterial structures, with two left-handed (backward) and two right-handed (forward) pass bands, are investigated. Also, design procedures in order to design dual- and quad-band E-CRLH-TLs are presented in detail and the parameters of these structures are extracted by clean formulas, while satisfying arbitrary phase shifts at the operating frequencies. Finally, the dispersion and characteristic impedances of these transmission lines are derived and plotted. The results of this paper can be applied to any type of TL-based dual- and quad-band microwave component
Performance evaluation of energy meters in nonses'usoidal environment based on IEEE 1459 standard
, Article 22nd International Conference and Exhibition on Electricity Distribution, CIRED 2013; Stockholm; Sweden; 10 June 2013 through 13 June 2013 ; Volume: 2013, Issue: 615 , 2013 ; 9781849197328 (ISBN) ; Honarmand, M. E ; Ouni, S ; Mehri, R ; Behinh, Y ; Mokhtari, H ; Talebi, J ; Sharif University of Technology
2013
Abstract
The objective of this work is to study the effects of harmonics on energy meters. This study is canied out based on IEEE 1459 standard through extensive tests on some energy meters installed at Gil an utility consumers. First, a review on IEEE 1459 standard on power definitions will be given. The definitions are then ervaluated for a compact Fluorescent Lamp (CFL) as a harmonic generating load. Then, the results of the performance e-alnation of two energy meters are presented for different linear and nonlinear loads based on IEEE1459 standard power definitions. Two different test procedures are performed for this putpose. In the first series of tests, a harmonic polluted voltage is applied...
NETAL: A new graph-based method for global alignment of protein-protein interaction networks
, Article Bioinformatics ; Volume 29, Issue 13 , 2013 , Pages 1654-1662 ; 13674803 (ISSN) ; Khadem, A ; Hashemifar, S ; Arab, S. S ; Sharif University of Technology
2013
Abstract
Motivation: The interactions among proteins and the resulting networks of such interactions have a central role in cell biology. Aligning these networks gives us important information, such as conserved complexes and evolutionary relationships. Although there have been several publications on the global alignment of protein networks; however, none of proposed methods are able to produce a highly conserved and meaningful alignment. Moreover, time complexity of current algorithms makes them impossible to use for multiple alignment of several large networks together.Results: We present a novel algorithm for the global alignment of protein-protein interaction networks. It uses a greedy method,...
Effect of landmark configuration on target registration error for vertebra: A phantom study
, Article Proceedings of SPIE - The International Society for Optical Engineering ; Volume 8671 , 2013 ; 0277786X (ISSN) ; 9780819494450 (ISBN) ; Ahmadian, A ; Seraj, N. D ; Saberi, H ; Khoiy, K. A ; Sharif University of Technology
2013
Abstract
The configuration of landmarks is an important issue in minimizing the target registration error (TRE). In this paper the effect of different landmark configurations on the accuracy of pedicle screw placement during image guided spine surgery (IGSS) is investigated. Since the spine is deformed in intra-operative conditions compared to the preoperative situation, an accurate alignment of each vertebra is crucial to compensate for the deformation. CT compatible markers are placed over anatomical landmarks which are feasible and routinely used in surgical procedures. The TRE is obtained directly for the markers which are placed on the right and left pedicle of the vertebra. The estimated TRE...
High-fidelity magnetic characterization and analytical model development for switched reluctance machines
, Article IEEE Transactions on Magnetics ; Volume 49, Issue 4 , 2013 , Pages 1505-1515 ; 00189464 (ISSN) ; Kaboli, S ; Davoudi, A ; Moayedi, S ; Sharif University of Technology
2013
Abstract
This paper proposes a new experimental procedure for magnetic characterization of switched reluctance machines. In the existing methods, phase voltage and current data are captured and further processed to find the flux linkage. Conventionally, assuming zero initial flux value, the flux linkage can be found by integrating the corresponding voltage term. However, the initial flux value is usually unknown, e.g., it can be nonzero when the current is zero due to the residual flux effect, and, thus, imposes error in magnetic characterization. The proposed method addresses this issue by considering an additional equation in steady state. This method injects a low-frequency sinusoidal current to...
A new approach for automatic test pattern generation in register transfer level circuits
, Article IEEE Design and Test ; Volume 30, Issue 4 , 2013 , Pages 49-59 ; 21682356 (ISSN) ; Tabandeh, M ; Alizadeh, B ; Navabi, Z ; Sharif University of Technology
2013
Abstract
The article proposes an approach to generate high-level test patterns from the arithmetic model of a register-transfer-level (RTL) circuit using a hybrid canonical data structure based on a decision diagram. High-level simplified and fast symbolic path activation strategy as well as input justification is combined with test pattern generation for circuits under consideration. For simplification of a test procedure, some ATPG approaches have been introduced based on binary decision diagram (BDD) tools. Since these methods require the design to be flattened into the bit level, they cannot be used to deal with large industrial benchmarks efficiently, either in terms of memory or runtime....
GROTESQUE: Noisy group testing (Quick and Efficient)
, Article 2013 51st Annual Allerton Conference on Communication, Control, and Computing, Allerton 2013, Monticello, IL ; 2013 , Pages 1234-1241 ; 9781479934096 (ISBN) ; Jahangoshahi, M ; Bakshi, M ; Jaggi, S ; Sharif University of Technology
Abstract
Group-testing refers to the problem of identifying (with high probability) a (small) subset of D defectives from a (large) set of N items via a 'small' number of 'pooled' tests (i.e., tests have a positive outcome if even one of the items being tested in the pool is defective, else they have a negative outcome). For ease of presentation in this work we focus the regime when the number of defectives is sublinear, i.e., D = O (N1-δ) for some δ > 0. The tests may be noiseless or noisy, and the testing procedure may be adaptive (the pool defining a test may depend on the outcome of a previous test), or non-Adaptive (each test is performed independent of the outcome of other tests). A rich body...
A novel approach to design reversible counter rotating propeller fans
, Article ASME 2012 Gas Turbine India Conference, GTINDIA 2012, 1 December 2012 through 1 December 2012 ; December , 2012 , Pages 265-270 ; 9780791845165 (ISBN) ; Parizi, P. N ; Taheri, R ; Sharif University of Technology
2012
Abstract
Because of their high performance and unique abilities like producing none-rotating wake, Counter Rotating Propellers (C.R.P.) are being used in many advanced propulsion or ventilation systems. But due to complicated design procedure of C.R.P. fans up to now it was not possible to apply the concept in reversible systems. For the first time in this research, a new method presented to design a reversible counter rotating propeller system. This method is based on designing a basic C.R.P. by a reliable edition of blade element theory to achieve maximum performance in main rotating course and then to optimize it in order to have almost same performance in reverse rotating course. After expressing...
Blind source separation of discrete finite alphabet sources using a single mixture
, Article IEEE Workshop on Statistical Signal Processing Proceedings, 28 June 2011 through 30 June 2011, Nice ; June , 2011 , Pages 709-712 ; 9781457705700 (ISBN) ; Babaie Zadeh, M ; Samadi, S ; Jutten, C ; Sharif University of Technology
2011
Abstract
This paper deals with blind separation of finite alphabet sources where we have n sources and only one observation. The method is applied directly in time (spatial) domain and no transformation is needed. It follows a two stage procedure. In the first stage the mixing coefficients are estimated, and in the second stage the sources are separated using the estimated mixing coefficients. We also study restrictions of this method and conditions for which its performance is acceptable. Simulation results are presented to show the ability of this method to source separation in images and pulse amplitude modulation (PAM) signals
Evaluation of a novel extra-cardiac Fontan procedure with implantation of a biocompatible membrane
, Article IRBM ; Volume 36, Issue 5 , 2015 , Pages 287-292 ; 19590318 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Monjezi, M ; Navabi Shirazi, M. A ; Malakan Rad, E ; Sharif University of Technology
Elsevier Masson SAS
2015
Abstract
Fontan operation is a final palliative surgical treatment for patients with a single ventricle (SV) physiology. One of the common disadvantages of Fontan operation is to generate a non-pulsatile flow instead of the normal pulsatile flow produced by contraction of the ventricle. Theoretically, in SV patients, maintaining the antegrade flow through pulmonary valve can produce flow pulsatility in the right and left pulmonary arteries. However, it not only increases the energy loss in the Fontan of total cavopulmonary pathway (TCPC), but also imposes an extra load on pulmonary arteries as well as the ventricle. In this study, the potential capability of pulmonary valve of the patient that can be...
An experimental study of buffet detection on supercritical airfoils in transonic regime
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Volume 229, Issue 2 , 2015 , Pages 312-322 ; 09544100 (ISSN) ; Ehghaghi Bonab, M. B ; Soltani, M. R ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
Conventional buffet onset methods for a 2D supercritical airfoil, SC0410, in transonic regime for various Mach number and various angles of attack have been surveyed. The existing methods give good results for high subsonic and transonic regimes, but demand a computational procedure to detect the buffet onset. One of these methods, trailing edge pressure divergence, that have been recognized inappropriate in other studies for supercritical airfoils, shows acceptable result at least for the present supercritical airfoil. A new method has been proposed by the authors for transonic regime that is based on the physical definition of the buffet onset from the surface pressure distribution...
Accuracy and computational efficiency improvement of ray tracing using line search theory
, Article IET Microwaves, Antennas and Propagation ; Volume 4, Issue 9 , September , 2010 , Pages 1290-1299 ; 17518725 (ISSN) ; Shishegar, A ; Sharif University of Technology
2010
Abstract
This study presents a new ray tracing acceleration technique for site-specific propagation modelling in indoor environments. It overcomes one of the major problems regarding the computational efficiency of shooting-and-bouncing-ray (SBR) method, that is most of the rays emitted from the source do not reach the receiver whereas all of them must be traced. Our proposed method solves this problem in a two-step procedure based on the idea of line search theory. In the first step, called the bracketing phase, the solid angles around the transmitter that transport electromagnetic power to the receiver are determined. In the second step, called the sectioning or zoom phase, the accuracy is improved...
Reliability evaluation in power distribution system planning studies
, Article 2016 International Conference on Probabilistic Methods Applied to Power Systems, PMAPS 2016 - Proceedings, 16 October 2016 through 20 October 2016 ; 2016 ; 9781509019700 (ISBN) ; Fotuhi Firuzabad, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
In distribution system planning studies, reliability evaluation is performed during optimization procedure to calculate the interruption cost, DISCO's income and to check the viability of constraints related to reliability indices. In each iteration of the optimization algorithm a special plan is evaluated that is different from other plans. So the configuration and specification of the network which is one of the input information for reliability evaluation is changing continuously that makes difficulties for this evaluation. To solve these difficulties, this paper presents a systematic method for reliability evaluation in distribution planning studies. The proposed approach can be...
On the dynamic response of beams on elastic foundations with variable modulus
, Article Acta Mechanica ; 2016 , Pages 549-564 ; 00015970 (ISSN) ; Mofid, M ; Akin, J. E ; Sharif University of Technology
Springer-Verlag Wien
Abstract
An exact solution is established pertaining to the dynamic response of an Euler–Bernoulli beam resting on a Winkler foundation with variable subgrade modulus. The solution is performed by employing the infinite power series method. Moreover, using the Frobenius theorem, the proposed method is extended in order to solve the problems wherein the variation of the modulus is not an analytic function. The solution procedure is demonstrated through several illustrative examples, and the correctness of the results has been ascertained through comparison with recognized solutions in the literature. Finally, it is shown that the proposed method of solution is directly applicable to the more general...
RASA: A low-cost upper-torso social robot acting as a sign language teaching assistant
, Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 1 November 2016 through 3 November 2016 ; Volume 9979 LNAI , 2016 , Pages 630-639 ; 03029743 (ISSN) ; 9783319474366 (ISBN) ; Meghdari, A ; Alemi, M ; Sharif University of Technology
Springer Verlag
2016
Abstract
This paper presents the design characteristics of a new robot Assistant for Social Aims (RASA), being an upper-torso humanoid robot platform currently under final stages of development. This project addresses the need for developing affordable humanoid platforms designed to be utilized in new areas of social robotics research, primarily teaching Persian Sign Language (PSL) to children with hearing disabilities. RASA is characterized by three features which are hard to find at the same time in today’s humanoid robots: its dexterous hand-arm systems enabling it to perform sign language, low development cost, and easy maintenance. In this paper, design procedures and considerations are briefly...
A 3-legged parallel robot for long bone fracture alignment
, Article ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE 2017, 6 August 2017 through 9 August 2017 ; Volume 3 , 2017 ; 9780791858158 (ISBN) ; Farahmand, F ; Gallardo Alvarado, J ; Computers and Information in Engineering Division; Design Engineering Division ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2017
Abstract
The reduction of long bone fractures is traditionally an invasive procedure with drawbacks of intense force, soft tissue damage, and, both, rotational and longitudinal malalignment. To combat these drawbacks, we applied a novel, wide open, threelegged, 6-DOF parallel robot, to the current surgical procedure. This platform will balance the accuracy, payload, and workspace for the surgeon, resulting in more efficient, successful surgeries. The experimental tests on a phantom reveal that the mechanism is well capable of applying the desired reduction steps against the large muscular payloads with high accuracy. © 2017 ASME
Design and parameter study of integrated microfluidic platform for CTC isolation and enquiry; a numerical approach
, Article Biosensors ; Volume 8, Issue 2 , 18 June , 2018 ; 20796374 (ISSN) ; Ahmad, S ; Momeni, M ; Sharif University of Technology
2018
Abstract
Being the second cause of mortality across the globe, there is now a persistent effort to establish new cancer medication and therapies. Any accomplishment in treating cancers entails the existence of accurate identification systems empowering the early diagnosis. Recent studies indicate CTCs’ potential in cancer prognosis as well as therapy monitoring. The chief shortcoming with CTCs is that they are exceedingly rare cells in their clinically relevant concentration. Here, we simulated a microfluidic construct devised for immunomagnetic separation of the particles of interest from the background cells. This separation unit is integrated with a mixer subunit. The mixer is envisioned for...
A new approach for the reliability-based robust design optimization of mechanical systems under the uncertain conditions
, Article SAE Technical Papers, 10 April 2018 through 12 April 2018 ; Volume 2018-April , 2018 ; 01487191 (ISSN) ; Sharafi, M. H ; Sharif University of Technology
SAE International
2018
Abstract
A mechanical system inherently affected by the conditions, factors, and parameters of uncertainties. Without including the uncertainty effects in the design procedure, the designs may not be robust and reliable. Robust design optimization (RDO) method is a procedure to find the insensitive design with respect to the variations. On the other hand, reliability is measured by the probability of satisfying a specific design criterion. Therefore, a reliable design is a design that satisfies the specified criteria even with some uncertainties in variables and parameters. Reliability-based design optimization (RBDO) is an optimization procedure that incorporates reliability requirements to find the...