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Reliability of 3-Dimensional scapular kinematics measures of acromion marker cluster in patients with shoulder impingement syndrome during humeral elevation and lowering
Roshanak Keshavarz,Hassan Shakeri,Amir Massoud Arab,Esmail Ibrahimi Tokamjani
Pajouhan Scientific Journal , 2013,
Abstract: Introduction: The purpose of this study was to investigate the Reliability of 3-D scapular kinematics measures of Motion analyzer and Acromion cluster in patients with Shoulder impingement syndrome during humeral elevation and lowering.Material & Methods: 20 Patients (Males=13, Females=7) with Shoulder Impingement Syndrome (mean age: 46.15 years) who participated in the study. They elevated and lowered humerous in frontal, sagittal and scapular movement plane during 8 seconds, using the VICON motion analyzer and Acromion marker cluster. The Scapular 3-D kinematics was measured, using VICON motion analyzer and Acromion marker cluster. Interclass correlation coefficient and Standard error of measurement were used.Results: Participants showed average of age 46.53±13.314 as well as average of BMI 28.14±3.93, and all quantitative and qualitative variables had the normal distribution. Trial-to-trial ICCs for the 3-D scapular kinematics variables for both elevation and lowering condition in the sagittal, frontal and scapular planes ranged from 0.58 to 0.99, which indicated fair to excellent reliability, and the SEM for both elevation conditions ranged from 1.7 to 15.4 .Discussion: The reliability of the three-dimensional scapular attitudes for elevation and lowering phases were very good. The estimation of three-dimensional scapular attitudes using the method of calculation relative to the trunk is reproducible in the three movement planes during elevation and lowering phases and can be used to document the scapular behavior.
The relationship between hip abductor muscle strength and iliotibial band tightness in individuals with low back pain
Amir M Arab, Mohammad R Nourbakhsh
Chiropractic & Manual Therapies , 2010, DOI: 10.1186/1746-1340-18-1
Abstract: A total of 300 subjects with and without LBP between the ages of 20 and 60 participated in this cross-sectional study. Subjects were categorized in three groups: LBP with ITB tightness (n = 100), LBP without ITB tightness (n = 100) and no LBP (n = 100). Hip abductor muscle strength was measured in all subjects.Analysis of Covariance (ANCOVA) with the body mass index (BMI) as the covariate revealed significant difference in hip abductor strength between three groups (P < 0.001). Post hoc analysis showed no significant difference in hip abductor muscle strength between the LBP subjects with and without ITB tightness (P = 0.59). However, subjects with no LBP had significantly stronger hip abductor muscle strength compared to subjects with LBP with ITB tightness (P < 0.001) and those with LBP without ITB tightness (P < 0.001).The relationship between ITB tightness and hip abductor weakness in patients with LBP is not supported as assumed in theory. More clinical studies are needed to assess the theory of muscle imbalance of hip abductor weakness and ITB tightness in LBP.Shortening of the iliotibial band (ITB) has been considered to be associated with low back pain (LBP) [1-4]. Stretching of the ITB is frequently recommended in LBP treatment programs [1,3,5]. However, the exact cause of ITB shortness in persons with LBP has not yet been determined. Anatomically, the ITB is a continuation of the tendinous portion of the tensor fascia lata (TFL) muscle with some contributions from the gluteal muscles. TFL/ITB is a synergist of gluteus medius muscle in hip abduction [6]. Hip abductor muscles play a significant role in control of rotational alignment of the limb and maintaining pelvic lateral stability in single leg stance [1,6,7]. Gottschalk et al [8] believe that the primary function of hip abductors is to stabilize the femoral head in the acetabulum during different parts of the gait cycle. The anterior and middle parts of the gluteus medius have a more vertical pull and
Altered muscular activation during prone hip extension in women with and without low back pain
Amir M Arab, Leila Ghamkhar, Mahnaz Emami, Mohammad R Nourbakhsh
Chiropractic & Manual Therapies , 2011, DOI: 10.1186/2045-709x-19-18
Abstract: Convenience sample of 20 female participated in the study. Subjects were categorized into two groups: with LBP (n = 10) and without LBP (n = 10). The electromyography (EMG) signal amplitude of the tested muscles during PHE (normalized to maximum voluntary electrical activity (MVE)) was measured in the dominant lower extremity in all subjects.Statistical analysis revealed greater normalized EMG signal amplitude in women with LBP compared to non-LBP women. There was significant difference in EMG activity of the IES (P = 0.03) and CES (P = 0.03) between two groups. However, no significant difference was found in EMG signals of the GM (P = 0.11) and HAM (P = 0.14) among two groups.The findings of this study demonstrated altered activation pattern of the lumbo-pelvic muscles during PHE in the women with chronic LBP. This information is important for investigators using PHE as either an evaluation tool or a rehabilitation exercise.Low back pain (LBP) is one of the most common and costly musculoskeletal complaints in today's societies, affecting up to 70-80% of the population at least one episode during their lifetime [1,2]. Despite its high incidence and detrimental effects on individuals' activities, the exact causes of mechanical LBP have not yet been fully understood as any approach to diagnosis or treatment has been shown to be clearly effective. However, during the recent decades the approach in assessment and treatment of LBP has been progressed from strengthening of lumbo-pelvic muscles toward modification of the motor system [3]. Balanced motor system is resulted from coordinated activity of synergist and antagonist muscles. According to this point of view, repetitive movements and long-term faulty postures will change muscle tissue characteristics and can lead to muscle dysfunction, altered movement pattern, pain and finally movement disorders [3]. Increased or decreased muscle activity and delayed muscular activation can change the normal movement pattern [4,5].
Effect of occlusal relationship on periodontal parameters
Hamid Reza Arab,Amir Moien Taghavi,Naser Sargolzaei,Reza Goharian
Journal of Isfahan Dental School , 2011,
Abstract: Introduction: The role of occlusal forces on dentition affected by periodontal diseases is not well known. Evidence suggests that high occlusal forces alter the extent of destruction and the nature of lesions. The effect of occlusal relationship on the periodontium has not been elucidated despite large number of studies, which have yielded contradictory results. The aim of this study was to evaluate the effect of different occlusal relationships on periodontal parameters.Materials and Methods: In this cross-sectional study, 60 healthy individuals were selected with anterior rise, cuspid rise, and group function occlusal relationships (n = 20). They had no premature contacts on the balancing side. Periodontal parameters of pocket depth, attachment level, keratinized gingiva, gingival recession and plaque index were recorded. Data were analyzed with ANOVA and Kruskal-Wallis test (α = 0.05).Results: Tukey test showed significant differences only in keratinized gingiva between anterior rise and cuspid rise occlusal relationships; in addition, Tukey test revealed significant differences in the upper jaw keratinized gingiva between anterior rise and cuspid rise occlusal relationships (p value < 0.05).Conclusion: The results of this study did not determine which occlusal relationship is superior to others, although an increase in the keratinized gingiva was noted in cuspid rise occlusal relationship. In other words, all the three relationships had similar effects on periodontal parameters of pocket depth, attachment level, and gingival recession. Key words: Dental occlusion, periodontal parameters
TRUNCATED ZERO INFLATED BINOMIAL CONTROL CHART FOR MONITORING RARE HEALTH EVENTS
Amir Afshin Fatahi, Rassoul Noorossana, Pershang Dokouhaki & Massoud Babakhani
International Journal of Research and Reviews in Applied Sciences , 2010,
Abstract:
Learning-Based Modular Indirect Adaptive Control for a Class of Nonlinear Systems
Mouhacine Benosman,Amir-massoud Farahmand,Meng Xia
Computer Science , 2015,
Abstract: We study in this paper the problem of adaptive trajectory tracking control for a class of nonlinear systems with parametric uncertainties. We propose to use a modular approach, where we first design a robust nonlinear state feedback which renders the closed loop input-to-state stable (ISS), where the input is considered to be the estimation error of the uncertain parameters, and the state is considered to be the closed-loop output tracking error. Next, we augment this robust ISS controller with a model-free learning algorithm to estimate the model uncertainties. We implement this method with two different learning approaches. The first one is a model-free multi-parametric extremum seeking (MES) method and the second is a Bayesian optimization-based method called Gaussian Process Upper Confidence Bound (GP-UCB). The combination of the ISS feedback and the learning algorithms gives a learning-based modular indirect adaptive controller. We show the efficiency of this approach on a two-link robot manipulator example.
Dose Assessment for Some Industrial Gamma Sources with an Application to a Radiation Accident  [PDF]
Eman Massoud
Open Journal of Modelling and Simulation (OJMSi) , 2014, DOI: 10.4236/ojmsi.2014.21003
Abstract:

Accidents involving industrial radiography are the most frequent cause of severe or fatal overexposure to workers and the public. On May 5, 2000, a radiation accident happened at a construction site in a gamma radiography practice at the village of Meet Halfa-Egypt. The accident was a severe overdose of non-radiation workers due to external exposure of Ir-192. This paper provides a methodology for calculating doses and dose rates from the most commonly used industrial γ-sources: 192Ir, 60Co, 134Cs, 137Cs and 131I. For this purpose, MCNP computer code based on Monte Carlo technique is used. The applied method helps firstly in studying and analyzing the doses from the above mentioned sources. Secondly, it provides a lead container design in a trial to reduce the dose rate within the permissible. Computer models were used to simulate the 192Ir Meet Halfa accident. To verify these models, the calculated doses were compared with a well-known empirical formula to convert source activity into dose rate and then the models were applied at different distances to analyze the factors that affect the deposited dose in the human body to find out the dose received by the victims.

The Influence of Control Design on Energetic Cost during FES Induced Sit-to-Stand  [PDF]
Rasha Massoud
Journal of Biomedical Science and Engineering (JBiSE) , 2014, DOI: 10.4236/jbise.2014.714108
Abstract: This paper highlights the benefits of using intelligent model based controllers to produce FES induced sit-to-stand movement (FES-STS), in terms of reducing energy cost and producing more natural responses in comparison with conventional controllers. A muscle energy expenditure model for the quadriceps is implemented in the control design of FES-STS, then simulation is run for three different control designs: an adaptive neuro-fuzzy inference system controller (ANFIS), a conventional PID controller, and a hybrid ANFIS-PID controller. The PID control strategy results in negative energy expenditure of the quadriceps at the end of the STS initiation phase, this negative energy is caused by the high lengthening speeds at the muscle fiber level, which may lead to muscle fatigue or damage. Contrary to PID controller, model based controllers show positive energy expenditure, lower energy costs, and more natural curves of energy expenditure and knee torques.
Classification-based Approximate Policy Iteration: Experiments and Extended Discussions
Amir-massoud Farahmand,Doina Precup,André M. S. Barreto,Mohammad Ghavamzadeh
Mathematics , 2014,
Abstract: Tackling large approximate dynamic programming or reinforcement learning problems requires methods that can exploit regularities, or intrinsic structure, of the problem in hand. Most current methods are geared towards exploiting the regularities of either the value function or the policy. We introduce a general classification-based approximate policy iteration (CAPI) framework, which encompasses a large class of algorithms that can exploit regularities of both the value function and the policy space, depending on what is advantageous. This framework has two main components: a generic value function estimator and a classifier that learns a policy based on the estimated value function. We establish theoretical guarantees for the sample complexity of CAPI-style algorithms, which allow the policy evaluation step to be performed by a wide variety of algorithms (including temporal-difference-style methods), and can handle nonparametric representations of policies. Our bounds on the estimation error of the performance loss are tighter than existing results. We also illustrate this approach empirically on several problems, including a large HIV control task.
Bellman Error Based Feature Generation using Random Projections on Sparse Spaces
Mahdi Milani Fard,Yuri Grinberg,Amir-massoud Farahmand,Joelle Pineau,Doina Precup
Computer Science , 2012,
Abstract: We address the problem of automatic generation of features for value function approximation. Bellman Error Basis Functions (BEBFs) have been shown to improve the error of policy evaluation with function approximation, with a convergence rate similar to that of value iteration. We propose a simple, fast and robust algorithm based on random projections to generate BEBFs for sparse feature spaces. We provide a finite sample analysis of the proposed method, and prove that projections logarithmic in the dimension of the original space are enough to guarantee contraction in the error. Empirical results demonstrate the strength of this method.
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