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Geoscience Frontiers 2016年第1期7卷 83-89页

作者： ali reza kashani Amir Hossein Gandomi Mehdi Mousavi Department of Civil Engineering Arak University Department of Civil Engineering The University of Akron

In this study, Imperialistic Competitive Algorithm（ICA） is utilized for locating the critical failure surface and computing the factor of safety（FOS） in a slope stability analysis based on the limit equilibrium approach. The factor of safety relating to each trial slip surface is calculated using a simplified algorithm of the Morgenstern-Price method, which satisfies both the force and the moment equilibriums. General slip surface is considered non-circular in this study that is constituted by linking random straight *** explore the performance of the proposed algorithm, four benchmark test problems are analyzed. The results demonstrate that the present techniques can provide reliable, accurate and efficient solutions for locating the critical failure surface and relating FOS. Moreover, in contrast with previous studies the present algorithm could reach the lower value of FOS and reached more exact solutions.

关键词： Meta-heuristic algorithms Morgen-stern and price method Non-circular slip surface Imperialistic competitive algorithm

Designing a Carbon Nanotube Field-Effect Transistor with High Transition Frequency for Ultra-Wideband Application

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Engineering（科研） 2017年第1期9卷 22-35页

作者： Ramin Nouri-Bayat ali reza kashani-Nia Central Tehran Branch Islamic Azad University Tehran Iran

Theoretical calculations predict transition frequencies in the terahertz range for the field-effect transistors based on carbon nanotubes, and this shows their suitability for being used in high frequency applications. In this paper, we have designed a field-effect transistor based on carbon nanotube with high transition frequency suitable for ultra-wide band applications. We did this by optimizing nanotube diameter, gate insulator thickness and dielectric constant. As a result, we achieved the transition frequency about 7.45 THz. The environment of open source software FETToy is used to simulate the device. Also a suitable model for calculating the transition frequency is presented.

关键词： Carbon Nanotube Field-Effect Transistor (CNTFET) Transition Frequency Ultra-Wide Band (UWB) FETToy

The Behavior of Rectangular and Circular Reinforced Concrete Columns Under Biaxial Multiple Excitation

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 677-691页

作者： Mohammad reza Salami Ebrahim Afsar Dizaj Mohammad Mehdi kashani School of Engineering and the Built Environment Birmingham City UniversityBirminghamUK Department of Civil Engineering Azarbaijan Shahid Madani UniversityTabrizIran Department of Civil Engineering University of SouthamptonSouthamptonUK

The aim of this study is to investigate the dynamic performance of rectangular and circular reinforced concrete(RC)columns considering biaxial multiple *** this purpose,an advanced nonlinear finite element model which can simulate various features of cyclic degradation in material and structural components is *** implemented nonlinear fiber beam-column model accounts for inelastic buckling and low-cycle fatigue degradation of longitudinal reinforcement and can simulate multiple failure modes of RC columns under dynamic *** rectangular and circular columns are used to investigate the failure modes of RC columns.A detailed ground motion selection is implemented to generate real mainshock and *** was found that multiple excitations due to aftershock has the potential of increasing the damage of the RC columns and longitudinal reinforcements are significantly affected low-cycle ***,it was found that rectangular column is more sensitive to accumulative damage due to cyclic *** study increases the accuracy of structural analysis of RC columns and consequently improves understanding the failure modes of RC columns with different cross-sectional shapes.

关键词： RC column biaxial loading multiple excitations low-cycle fatigue

Attitude Control of a Flexible Satellite by Using Robust Control Design Methods

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Intelligent Control and Automation 2013年第3期4卷 313-326页

作者： reza Mohsenipour Hossein Nemati Mehrzad Nasirian Abdolreza kashani Nia East Tehran (QiamDasht) Branch Islamic Azad University Tehran Iran Malekashtar University of Technology Tehran Iran

The increase of satellite’s dimensions has caused flexibility and formation of uncertainty in their model. This is because of space missions being more complex and using light moving structures in satellites. Satellites are also encountered with various circumferential disturbance torques. This uncertainty in model and disturbance torques will cause undesirable performance of satellites’ attitude control system. So, for attitude control of these satellites, those methods should be used which are robust to uncertainty of the plant’s model and can reject the effects of disturbances and the measurement noise. One of these methods is the robust control design method. But, because of pole’s place of these satellite’s dynamics equations, the designing procedure of robust control will face difficulties. In this paper, by using an internal feedback as a novel idea, the satellite’s dynamics equations are changed in such a way that the poles will be placed in proper locations. Then, for these new equations, by regarding the effects of flexibility as uncertainty and considering the uncertainty in inertia matrix of satellite, an H∞ controller has been designed and for better performance, a μ-controller has been improved. Afterwards, these two controllers are analyzed and compared for the original dynamic equations, not for the modified ones. Also, for comparison, a classic controller has been also designed for the original plant and eventually all these three controllers are compared with each other.

关键词： Attitude Control of Satellite Robust Control Flexible Satellite Uncertainty

A minimum data set for traumatic brain injuries in Iran

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Chinese Journal of Traumatology 2022年第5期25卷 283-292页

作者： Maryam Edalatfar Mohsen Sadeghi-Naini Hamid reza Khayat kashani Mitra Movahed Mahdi Sharif-Alhoseini Department of Neurosurgery Imam Hossein HospitalShahid Beheshti University of Medical SciencesTehranIran Department of Psychology HELP UniversityKuala LumpurMalaysia Sina Trauma and Surgery Research Center Tehran University of Medical SciencesTehranIran

Purpose: Traumatic brain injury (TBI) is one of the major public health concerns worldwide. Developing a TBI registry could facilitate characterizing TBI, monitoring the quality of care, and quantifying the burden of TBI by collecting comparable and standardized epidemiological and clinical data. However, a national standard tool for data collection of the TBI registry has not been developed in Iran yet. This study aimed to develop a national minimum data set (MDS) for a hospital-based registry of patients suffering from TBI in Iran. Methods: The MDS was designed in 2 phases, including a literature review and a Delphi study with content validation by an expert panel. After the literature review, a comprehensive list of administrative and clinical items was obtained. Through a two-round e-Delphi approach conducted by invited experts with clinical and research experience in the field of TBI, the final data elements were selected. Results: A MDS of TBI was assigned to 2 parts: administrative part with 5 categories including 52 data elements, and clinical part with 9 categories including 130 data elements. Conclusion: For the first time in Iran, we developed a MDS specified for TBI consisting of 182 data elements. The MDS would facilitate implementing a TBI’s national level registry and providing essential, comparable and standardized information.

关键词： Traumatic brain injuries Registries Data systems

Hybrid External Fixation for Open Severe Comminuted Fractures of the Distal Femur

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Surgical Science 2013年第2期4卷 176-183页

作者： Ebrahim Ghayem Hassankhani ali Birjandinejad Farzad Omidi kashani Golnaz Ghayem Hassankhani Department of Orthopedics and Spine Surgery Orthopedic Research Center Imam Reza Hospital Mashhad University of Medical Sciences Mashhad Iran Department of Orthopedics Surgery Imam Reza Hospital Mashhad University of Medical Sciences Mashhad Iran Department of Orthopedics Surgery Shahid Kamiab Hospital Mashhad University of Medical Sciences Mashhad Iran Mashhad University of Medical Sciences Mashhad Iran

Background: The treatment of distal femoral open comminuted fractures is a major problem for orthopedic surgeon. The basic and important aim in treatment of these fractures is to assemble the condylar fragments and then fix the condyles to the femoral shaft by minimum handling of the bone and soft tissues. Objectives: To evaluate the treatment of distal femoral open comminuted fractures (type C2 and C3) with hybrid external fixator. Methods: Thirty-four patients with distal femur open comminuted fracture (type C2 and C3) were treated by hybrid external fixator between January 2005 and December 2008. All of the fractures were opened with extension to joint surface. 30 patients were male and 4 were female. Their average age was 30.5 years (17 to 72 years). Average follow up period was 36 months. 12 patients had isolated fracture and 22 patients had multiple fractures. The bony and functional results were evaluated by the association for the study and application of the method of Ilizarov (ASAMI) protocol and knee society score. Results: 29 out of 34 fractures (85%) had union without bone grafts. Average time of union was 6.1 months (4 - 19 ms). The average knee range of motion was 87.5 degrees (30 - 115 degrees). The bony results were excellent in 24 patients (70.5%), good in 6 (17.7%), fair in 2 (5.9%), and poor in 2 (5.9%), and the functional results were excellent in 10 (29.4%) patients, good in 14 (41.2%), fair in 6 (17.6%), and poor in 4 (11.8%), and the functional results were excellent in 10 (29.4%) patients, good in 14 (41.2%), fair in 6 (17.6%), and poor in 4 (11.8%) according to ASAMI protocol. According to the knee society score the functional results were excellent in 9 (26.44%) patients, good in 13 (38.26%), fair in 7 (20.6%), and poor in 5 (14.7%). Conclusion: Hybrid external fixator is an effective method for treatment of distal femoral open comminuted fractures (type C2 and C3) and may be considered as an alternative surgical methods in the management

关键词： Hybrid External Fixator Open Fractures Distal Femoral Fracture Type C2 and C3

白炭黑粒径对丁苯橡胶微米和纳米复合材料分子链动态性能和摩擦性能的影响

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轮胎工业 2015年第3期35卷 165-170页

作者： Mohammad-reza Pourhossaini Mehdi Razzaghi-kashani 肖大玲 Polymer Engineering Department Faculty of Chemical EngineeringTarbiat Modares University 北京橡胶工业研究设计院

橡胶材料在硬表面的摩擦性能与橡胶内部摩擦有关且具有整体性已被证实。Grosch进一步的研究表明,橡胶材料摩擦性能与滑动速度的相关性跟其粘弹性与温度的相关性一致。因此,摩擦因数-速度关系主曲线类似于动态性能损耗因子-频率曲线。虽... 详细信息

橡胶材料在硬表面的摩擦性能与橡胶内部摩擦有关且具有整体性已被证实。Grosch进一步的研究表明,橡胶材料摩擦性能与滑动速度的相关性跟其粘弹性与温度的相关性一致。因此,摩擦因数-速度关系主曲线类似于动态性能损耗因子-频率曲线。虽然软橡胶在硬表面摩擦的本质与橡胶内部滞后以及界面间粘合性能不同,但研究认为,由于静电力作用使橡胶产生附着和分离,形成纳米级粗糙表面从而导致小幅变形,

关键词：纳米复合材料摩擦性能子链动态性能损耗因子表面摩擦黑粒频率曲线粘合性能主曲线

Surgical Treatment of Scoliosis in Patients with Charcot-Marie-Tooth Disease

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海南医学院学报 2009年第3期15卷 227-230页

作者： Farzad Omidi kashani Ibrahim Ghayem Hasankhani Mahdi Banaii Orthopedic department Imam Reza Hospital Mashhad University of Medical Sciences Mashhad Iran

Objective:Apparently, scoliosis occurs in approximately one-third of patients with Charcot-Marie-Tooth disease. Little is known about the response of these curves to treatment. The purpose of this study was to evaluate the results of spinal surgery in these peculiar patients. Methods: We retrospectively evaluated the results of spinal surgery in eight patients who had scoliosis due to clinically and electrophysiologically proven Charcot-Marie-Tooth disease. Radiographs were reviewed. The location and direction of the curve pattern, the age at the time of surgery, type of surgery, number of levels fused, instrumentations used, intra or postoperative complications, and results and need for reoperation were recorded. Results: Eight patients associated with Charcot-Marie-Tooth disease who underwent scoliotic surgery were identified. The average age and curve at the time of surgery were 21.1 years and 56.4° respectively. 62.5% of the curves had left thoracic component and more than one third was associated with thoracic hyperkyphosis. Long posterior spinal fusion was performed most often, with an average of 11.5 spinal segments fused. Instrumentation was used in all posterior fusions. At an average of 39 months (range, 24 to 72 months) postoperatively, the fusion appeared to be solid in all patients. Conclusion: Scoliosis in patients with Charcot-Marie-Tooth disease differs from that in patients with idiopathic scoliosis in regarding to the etiology and the prevalence of thoracic hyperkyphosis, but the surgical management appears to be similar. Spondylodesis does not appear to be associated with a high rate of complications.

关键词：腓骨肌萎缩症脊柱治疗方法临床分析

Treatment of Complex Proximal Tibial Fractures (Types V &VI of Schautzker Classification) by Double Plate Fixation with Single Anterior Incision

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Open Journal of Orthopedics 2013年第4期3卷 208-212页

作者： Ebrahim Ghayem Hassankhani Farzad Omidi kashani Golnaz Ghayem Hassankhani Orthopedic and Spine Surgery Imam Reza Hospital Mashad University of Medical Sciences Mashad Iran.

Background: complex proximal tibial fractures (Types V & VI of Schautzker classification) are the major problems in orthopedic surgery and associated with high complication rates. There are many alternatives in treatment of these fractures. Aim: to evaluate the results of double plating with single anterior incision in complex proximal tibial fractures (Types V& VI of Schautzker classification).Methods and Materials: 22 patients (16 males and 6 females) with Types V and VI of Schautzker classification of proximal tibial fractures (14 cases were Type V and 8 cases were Type VI) were treated by double plating with single anterior incision method between May 2006 and May 2011. The bony and functional outcome was evaluated according to Knee Society Score. Results: According to Knee Society Score, the results were as follows: excellent in 19 patients (86.4%), good in 2 patients (9.1%), fair in 1 patient (4/5%), and poor in no patient (0%).Conclusion: the double plate fixation with single anterior incision is the best, effective and simple procedure in treatment of complex proximal tibial fractures (Types V and VI of Schautzker classification).

关键词： Proximal Tibial Fractures Types V & VI of Schautzker Classification Double Plate Fixation Single Anterior Incision