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Losses Calculation of an Aerospace Retraction Wheel Motor with Regarding to Electromagnetic-Field Analysis Investigation

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Journal of Energy and Power Engineering 2016年第3期10卷 183-190页

作者： pedram Asef Ramon Bargallo Perpina Department of Electrical Engineering Polytechnic University of Catalonia-BarcelonaTech Barcelona CAT 08036 Spain

A 3-D FEA （finite element analysis） transient and steady-state design proposal for high-speed with Nd-Fe-Br （reversible） magnets in aerospace application will be examined under design considerations of n = 12,000 rpm, short-duty, sinusoidal drive, low cogging, high efficiency at peak torque, and etc. for an ARWM （aerospace retraction wheel motor）. In construction, the PMs （permanent magnets） fixed on the rotor core which is surface-mOunted magnets retained by a carbon-fiber bandage. Redundant windings, resistant to fault propagation have accounted. Besides, an axial water-jacket housing without end-cap cooling has involved. All performed characteristic performances of the correlated ARWM will verify by comparison through 2-D and 3-D FEA results. In this paper, design process has dealing with determination of various kinds of losses such as electromagnetic and mechanical losses. In terms of both classified losses, copper, stator back iron, stator tooth, PM, rotor back iron, air-friction and sleeve losses were calculated. The 3-D end-winding effects were included in the modeled ARWM by the authors.

关键词： ARWM high-speed PM motor redundant winding sleeve end-winding short duty air-friction losses.

A system dynamics model for the assessment of the effects of advertising and sales promotion on profitability

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Journal of Modern Accounting and Auditing 2010年第10期6卷 12-26页

作者： Amir Ekhlassi pedram Tolouei Faculty of Management University of Tehran Tehran 15614 Iran

Advertising and sales promotion have significant impact on raising customer awareness. They are tools by which customers become acquainted with new and innovative products and services of the companies. Despite the importance of these tools in increasing sales, it is not easy to evaluate their effect on sales. One of the problems confronted by the marketing managers is the determination of a clear relationship between the effectiveness of advertising and sales promotion on profitability. In this article, considering the relationship between these tools and brand equity, we have attempted to determine the relationship between effectiveness of these two factors and profitability. Next, a system dynamics model for representing the effects of marketing communication tools on company profitability is offered. Finally, using the data from a corporation and the numeric values related to each of the elements in the model, an attempt has been made to determine a number representing the magnitude of the effect of advertising and sales promotion on the corporation＇s revenue and profitability and to draw the respective curves related to the effects of these two factors.

关键词： advertising sales promotion brand equity profitability system dynamics

Weighted Sum Rate Maximization in OFDM Based Cooperative Cognitive Radios: A Joint Optimization Approach

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International Journal of Communications, Network and System Sciences 2012年第5期5卷 263-271页

作者： pedram Johari Vahid Tabataba Vakili Communications Engineering Department School of Electrical Engineering Iran University of Science and Technology (IUST) Tehran Iran

Improving utilization of the radio spectrum is the main goal of Cognitive Radio Networks (CRN). Recent studies made use of cooperative relay technology in cognitive networks, to increase transmission diversity gain. In this paper we consider an OFDM based cooperative cognitive network with a pair of Source-Destination nodes as the primary user (PU), and a pair of Source-Destination nodes—which is assisted with a relay—as the secondary (cognitive) user (SU). Both primary and secondary users share a same spectrum. In a two hop transmission, the source transmits in the first hop, and the half-duplex relay decodes the message, re-encodes and forwards it to the destination in the second hop on a different subcarrier. The cognitive network obeys an underlay paradigm where the SU is allowed to transmit simultaneously with PU, while its power is limited such that the interference caused for PU does not exceed a defined temperature. Under this constraint, a joint subcarrier pairing and power allocation is proposed for SU to maximize its weighted sum rate. The problem is transformed to a convex optimization problem and solved in the dual domain. Then an algorithm to achieve feasible solutions is used based on the optimization results. Through extensive simulations, we compare the spectrum utilization of the proposed approach with the existing ones, and show that interestingly the proposed method improves the weighted sum rate of SU.

关键词： Cooperative Cognitive Radio Underlay Transmission OFDM Joint Optimization

Design of High-Speed PM Synchronous Motor Thermal and Mechanical Analyzes Study for Aerospace Retraction Wheel Motor Application

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Journal of Energy and Power Engineering 2016年第4期10卷 258-267页

作者： pedram Asef Ramon Bargallo Perpina Department of Electrical Engineering Polytechnic University of Catalonia-BarcelonaTech Barcelona CA T 08036 Spain

A 3-D modeling of FEA （finite element analysis） design provides for high-speed synchronous with PMs （permanent magnets） applied in aerospace application will be examined under design considerations ofn = 12,000 rpm, short-duty operation, and etc. for an ARWM （aerospace retraction wheel motor）. First, lumped-elements will be fine-tuned following numerical method results is reported steady-state and transient solutions. Besides, the equations of thermal modeling such as Re, N,,, G,. and Pr numbers in order to calculate heat-transfer coefficient of convection on the rotor and stator surfaces in the air-gap have calculated. This section illustrates the temperature distribution of each point in a clear view. By CFD （fluid dynamic analysis） analysis, the fluid dynamics were modeled, pressure and velocity streamlines of cooling-flow have analyzed. An optimization algorithm was derived in order to have optimized number of water-channels as well. Second, calculation of nodal and tangential forces which deal with mechanical stresses of the ARWM have represented. The paper discusses an accurate magnetic-field analysis that addresses equivalent stress distribution in the magnetic core through using the transient FEA to estimate motor characteristics. The whole model shear and normal mechanical stresses and total deformation oftbe ARWM has been investigated by transient FEA. The end-winding effects were included by the authors.

关键词： ARWM high-speed PM motor redundant winding equivalent stress distribution lumped-elements.

Pericardial Rupture and Chronic Subluxation of the Heart: A Case Report

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World Journal of Cardiovascular Surgery 2021年第9期11卷 75-81页

作者： pedram Rajabifard Anurag Agarwal Peter Skillington Department of Cardiothoracic Surgery Royal Melbourne Hospital Victoria Australia

Background: Pericardial rupture is a rare diagnosis, usually occurring secondary to high energy blunt force trauma, which can result in subluxation of the heart. Aim: To determine a suitable method for repair of a pericardial defect post traumatic pericardial rupture. Case: We present a 55-year-old male who was found to have a large pericardial defect intra-operatively while undergoing an elective Ross procedure. The defect was repaired with a Gore-Tex membrane. The patient underwent revision sternotomy and repair of the pericardium due to inadequate laxity of the repaired pericardium resulting in hemodynamic instability. Conclusion: Synthetic membranes, such as Gore-Tex membranes, can be used successfully for repair of large pericardial defects but care must be taken to prevent undue tension secondary to taut repair, resulting in hemodynamic compromise.

关键词： Pericardial Rupture Pericardium Trauma Cardiac Trauma

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角膜共聚焦显微镜在干眼随访诊治中的应用

东南大学学报（医学版） 2015年第5期34卷 745-748页

作者：胡凯 HAMRAH pedram 东南大学附属中大医院眼科江苏南京210009 美国哈佛大学医学院附属麻省眼耳医院眼科美国波士顿02114

目的:评价角膜共聚焦显微镜检查在干眼随访诊治中的作用。方法:选取干眼新发病例150例(300眼),随机分为A、B两组,随访治疗半年。A组患者根据随访角膜共聚焦显微镜检查结果调整治疗方案,B组根据常规干眼检查结果调整治疗方案,两组所用具... 详细信息

目的:评价角膜共聚焦显微镜检查在干眼随访诊治中的作用。方法:选取干眼新发病例150例(300眼),随机分为A、B两组,随访治疗半年。A组患者根据随访角膜共聚焦显微镜检查结果调整治疗方案,B组根据常规干眼检查结果调整治疗方案,两组所用具体治疗药物及方法相同。结果:A组患者总的好转率为63%,明显高于B组的35%;并且经治疗后,A组患者的平均泪液分泌量(SⅠt)及泪膜破裂时间(BUT)明显好于B组。结论:根据角膜共聚焦显微镜检查结果调整干眼治疗方案效果明显好于传统随访治疗方案。

关键词：角膜共聚焦显微镜干眼治疗方案调整

An Adaptive Robust Approach to Modeling and Control of Flexible Arm Robots

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World Journal of Engineering and Technology 2018年第2期6卷 282-295页

作者： pedram Bagheri Laleh Behjat Qiao Sun Department of Electrical and Computer Engineering University of Calgary Calgary Alberta Canada Department of Mechanical and Manufacturing Engineering University of Calgary Calgary Alberta Canada

In this paper, a novel adaptive robust approach to modeling and control of a class of flexible-arm robots subject to actuators unmodeled dynamics is proposed. It is shown how real-time signals measured from a dynamical system can be utilized to improve the accuracy of the mathematical model of flexible robots. Given the elasticity of the robot’s arms, flexible manipulators have both passive and active degrees of freedom. A nonlinear robust controller is designed for the active degrees of freedom to enable the robot to follow desired trajectories in the presence of actuators unmodeled dynamics. Furthermore, it is shown that under some feasible conditions, another nonlinear robust controller is designed for the passive degrees of freedom. Moreover, to use the system response for model extraction, two auxiliary signals are proposed to provide sufficient information for improving the accuracy of the dynamics of the system numerically. Additionally, two adaptive laws are proposed in each case to update the two introduced auxiliary signals. As a result, the controller controls the passive degrees of freedom after the active degrees of freedom converge to their desired trajectories. Simultaneously, the information collected from the system to update the auxiliary signals enhances the model accuracy. In the end, simulation results are presented to verify the performance of the proposed controller.

关键词： Adaptive Control Robust Control Vibration Control

Application of a Rapid ESI-MS/MS Method for Quantitative Analysis of Docetaxel in Polymeric Matrices of PLGA and PLGA-PEG Nanoparticles through Direct Injection to Mass Spectrometer

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American Journal of Analytical Chemistry 2015年第2期6卷 164-175页

作者： pedram Rafiei Deborah Michel Azita Haddadi Division of Pharmacy College of Pharmacy and Nutrition University of Saskatchewan Saskatoon Canada

Docetaxel is a member of taxan family of antineoplastic agents widely used in cancer chemotherapy. However, application of conventional chemotherapy with commercial formulation has been accompanied with matters of concern regarding drug’s biodistribution, pharmacokinetics, and pharmacodynamics. Polymeric nanoparticles have been widely used as unique drug delivery vehicles to circumvent such problems. Docetaxel-loaded poly (lactide-co-glycolide) (PLGA) and poly (lactide-co-glycolide)-poly (ethylene glycol) (PLGA-PEG) nanoparticles fit well in modifying drug’s pharmacokinetic characteristics as intravenous (IV) sustained-release delivery vehicles. In such circumstances, characterization of nanoparticles in terms of their drug-payload would be a necessary step. The majority of studies have used HPLC analysis method for docetaxel quantitation in polymeric nanoparticles. Herein, a rapid ESI-MS/MS method for quantitative analysis of docetaxel in polymeric matrices of PLGA and PLGA-PEG nanoparticles through direct injection to mass spectrometer has been developed and validated. The assay was validated over a range of 3.9 - 1000 ng/ml and 125 - 16,000 ng/ml. Samples were directly injected to the instrument through an isocratic elution (0.1% formic acid in methanol) and detection was performed on a Hybrid Triple Quadrupole/Linear Ion trap mass spectrometer with multiple reaction monitoring (MRM) mode via positive electrospray ionization (ESI) source. The run time and retention time were 2 and 0.6 minutes respectively. The method demonstrated acceptable level of accuracy and precision and was successfully applied for quantitative analysis of docetaxel in polymeric nanoparticles of PLGA and PLGA-PEG.

关键词： Docetaxel EI-MS/MS Direct Injection Multiple Reaction Monitoring (MRM) Positive Electrospray Ionization (ESI+) PLGA PLGA-PEG

响应面法优化生物质灰处理TMP废水的工艺条件

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大连工业大学学报 2018年第1期37卷 28-34页

作者：孙勇慧刘忠 pedram FATEHI 天津科技大学天津市制浆造纸重点实验室天津300457 湖首大学化学工程系

研究了生物质灰(FA)去除热磨机械浆(TMP)废水中有机物的工艺条件,利用响应面Optimal Design建立数学模型,考察了FA质量浓度、温度和时间等影响因素对处理效果的影响。结果表明,FA处理TMP废水效果明显,建立的浊度、COD和木质素去除率的模... 详细信息

研究了生物质灰(FA)去除热磨机械浆(TMP)废水中有机物的工艺条件,利用响应面Optimal Design建立数学模型,考察了FA质量浓度、温度和时间等影响因素对处理效果的影响。结果表明,FA处理TMP废水效果明显,建立的浊度、COD和木质素去除率的模型,拟合情况良好,可预测任意期望值的去除率。增加FA用量、提高处理温度、延长处理时间有助于浊度、COD和木质素去除率的提高。FA处理TMP废水的最佳处理条件为:FA 100g/L,处理温度25℃,处理时间60min。此条件下处理的TMP废水,浊度为27.60NTU,COD为0.44g/L,木质素和半纤维的质量浓度分别为0.04和0.01g/L;浊度、COD和木质素去除率分别为96.2%、79.3%和95.4%。

关键词：生物质灰热磨机械浆 TMP废水响应面法