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Experimental investigation of shock-buffet criteria on a pitching airfoil

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Chinese Journal of Aeronautics 2022年第7期35卷 179-191页

作者： Mehran MASDARI Aghil ZEINALZADEH Mohammad Ali ABDI Mohammad reza soltani Faculty of New Sciences and Technologies University of TehranTehran ***Iran Department of Aerospace Engineering Sharif University of TechnologyTehran 11365-11155Iran Department of Aeronautical and Astronomical Engineering University of WashingtonSeattleWAUSA

An experimental investigation of the shock-buffet phenomenon subject to unsteady pitching supercritical airfoil around its quarter chord has been conducted in a transonic wind *** model was equipped with pressure taps connected to the fast response *** were conducted at different free-stream Mach number from 0.61 *** principle goal of this investigation was to experimentally discuss the shock-buffet criterion over a SC(2)-0410 supercritical pitching related to the hysteresis loops of total drag and trailing edge pressure,the behaviour of the shock wave foot location,the pressure distribution over the upper surface,and by implementing the wavelet analysis of the normal *** ensure capturing the buffet phenomenon by utilizing these criteria,a pressure port has been drilled exactly at the trailing edge of the airfoil where its output was used to detect the buffet phenomenon for different *** representation of the flow using the shadow graph flow visualization technique for different test cases is further used to illustrate the unsteady shock wave motion.A comparative analysis of experimental measurements shows that the conducted criteria confirm each other when the buffet phenomenon occurs at the position of the oscillating cycle.

关键词： Airfoil Buffeting Experimental analysis Hysteresis loops Pitching motion Shock wave Wavelet analysis

Effect of an end plate on surface pressure distributions of two swept wings

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Chinese Journal of Aeronautics 2017年第5期30卷 1631-1643页

作者： Mohammad reza soltani Mehran MASDARI Mohammad Rasoul TIRANDAZ Department of Aerospace Engineering Sharif University of Technology Tehran 19166Iran Faculty of New Sciences and Technologies University of Tehran Tehran Iran

A series of wind tunnel tests was conducted to examine how an end plate affects the pressure distributions of two wings with leading edge（LE） sweep angles of 23° and 40°. All the experiments were carried out at a midchord Reynolds number of 8×10～5, covering an angle of attack（AOA） range from -2° to 14°. Static pressure distribution measurements were acquired over the upper surfaces of the wings along three chordwise rows and one spanwise direction at the wing quarter-chord line. The results of the tests confirm that at a particular AOA, increasing the sweep angle causes a noticeable decrease in the upper-surface suction pressure. Furthermore, as the sweep angle increases, the development of a laminar separation bubble near the LEs of the wings takes place at higher AOAs. On the other hand, spanwise pressure measurements show that increasing the wing sweep angle results in forming a stronger vortex on the quarter-chord line which has lower sensitivity to AOA variation and remains substantially attached to the wing surface for higher AOAs than that can be achieved in the case of a lower sweep angle. In addition, data obtained indicate that installing an end plate further reinforces the spanwise flow over the wing surface, thus affecting the pressure distribution.

关键词： Chordwise Flow field Pressure distribution Swept wing Wind tunnel

A Deep Reinforcement Learning-Based Technique for Optimal Power Allocation in Multiple Access Communications

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Intelligent Automation & Soft Computing 2024年第1期39卷 93-108页

作者： Sepehr soltani Ehsan Ghafourian reza Salehi Diego Martín Milad Vahidi Department of Industrial Engineering College of EngineeringUniversity of HoustonHoustonTX77204USA Department of Computer Science Iowa State UniversityAmesIowaUSA ETSI de Telecomunicación Universidad Politécnica de MadridMadridSpain Faculty of School of Plant and Environmental Sciences Virginia Polytechnic Institute and StateUniversityBlacksburgVirginia24060USA

Formany years,researchers have explored power allocation(PA)algorithms driven bymodels in wireless networks where multiple-user communications with interference are ***,data-driven machine learning methods have become quite popular in analyzing wireless communication systems,which among them deep reinforcement learning(DRL)has a significant role in solving optimization issues under certain *** this purpose,in this paper,we investigate the PA problem in a k-user multiple access channels(MAC),where k transmitters(e.g.,mobile users)aim to send an independent message to a common receiver(e.g.,base station)through wireless *** this end,we first train the deep Q network(DQN)with a deep Q learning(DQL)algorithm over the simulation environment,utilizing offline ***,the DQN will be used with the real data in the online training method for the PA issue by maximizing the sumrate subjected to the source ***,the simulation results indicate that our proposedDQNmethod provides better performance in terms of the sumrate compared with the available DQL training approaches such as fractional programming(FP)and weighted minimum mean squared error(WMMSE).Additionally,by considering different user densities,we show that our proposed DQN outperforms benchmark algorithms,thereby,a good generalization ability is verified over wireless multi-user communication systems.

关键词： Deep reinforcement learning deep Q learning multiple access channel power allocation

Reproducibility of peripapillary retinal nerve fiber layer thickness measurements with Cirrus HD-OCT in glaucomatous eyes

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 113-117页

作者： reza soltani-Moghadam Yousef Alizadeh Ehsan Kazemnezhad Leili Mohamadreza Absari Haghighi Eye Research Center Amiralmomenin HospitalGuilan University of Medical Sciences Guilan University of Medical Sciences

AIM: To assess the reproducibility of Cirrus high-definition optical coherence tomography(HD-OCT; Carl Zeiss Meditec, Dublin, CA, USA) for analysis of peripapillary retinal nerve fiber layer(RNFL) thickness in glaucomatous eyesMETHODS: Forty-five eyes(one eye from each glaucomatous patient) were imaged with Cirrus *** eye was imaged three times by two separate operators. Intraclass correlation coefficient(ICC),coefficient of variation(CV), and test-retest variability were evaluated for both intraobserver and interobsever measurementsRESULTS: In intraobserver measurements, the average RNFL thickness ICC was 0.983. CV and test-retest variability were 2.3% and 4.4 μm respectively. In quadrants ICC ranged from 0.886 to 0.956, the lowest associated with nasal quadrant and CV ranged from 3.6%to 7.7%. In interobsever measurements, the average RNFL thickness ICC was 0.979. CV and test-retest variability were 2.4% and 4.5 μm respectively. In quadrants ICC ranged from 0.886 to 0.957, the lowest associated with nasal quadrant and CV ranged from 3.8%to 8.6%.CONCLUSION: The reproducibility of Cirrus OCT for RNFL thickness is sufficiently good to be useful clinically as a measure of glaucoma progression.

关键词： opticalcoherencetomography reproducibility glaucoma retinal nerve fiber layer

Photocatalytic Degradation of Ethylene Dichloride in Water Using Nano TiO<sub>2</sub>Supported on Clinoptilolite as a Photocatalyst

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Advances in Materials Physics and Chemistry 2012年第4期2卷 274-276页

作者： Manouchehr Nikazar Soheil Jalali Farahani Mastaneh reza soltani Chemical Engineering Department of Amirkabir University of Technology Tehran Iran

In this article one of the advanced oxidation processes (AOP) combined methods, photocatalyst /H2O2, is utilized in order to study photodegradation of ethylene dichloride (EDC) in water. Nano Titanium (IV) Oxide, supported on Clinoptilolite (CP) (Iranian natural zeolite) using solid-state dispersion (SSD) method for improvement of its photocatalytic properties. The results show that the TiO2/Clinoptilolite (SSD) is an active photocatalyst. The effects of five important photocatalytic reaction parameters including the initial concentration of ethylene dichloride, the ratio of TiO2/Clinoptilolite, the catalyst concentration, H2O2 concentration and pH in photodegradation of ethylene dichloride were examined. In this experiments, the design and also the optimum parameters were obtained by Taguchi Method, using Design Expert8®software. Taguchi's L27 (5^3) orthogonal array design was employed for the experimental plan. Four parameters were found to be significant whereas, pH was found to be an insignificant parameter after conducting experiments. A first order reaction with K = 0.007 min-1 was observed for the photocatalytic degradation reaction.

关键词： Photodegradation Photocatalysts TiO2/Clinoptilolite Ethylene Dichloride

以右侧髂協脓肿蛾首发表现的乙状结肠癌穿孔一例报道(英文)

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The Chinese-German Journal of Clinical Oncology 2012年第7期11卷 422-424页

作者： Mohammad Hossein Hajisadeghizadeh Hamid reza soltani.G Seyed Mohammad reza Mortazavizadeh Fatemeh Akhiri A General Surgery Yazd BranchI slamic Azad UniversityYazdIran Scientific Society of Medicine Yazd BranchI slamic Azad UniversityYazdIran Hematology and Oncology Yazd BranchI slamic Azad UniversityYazdIran

Colorectal cancer usually present with known symptoms while there are less common manifestation including abscess formation which can be intra or extra peritoneal. A 60-year-old Caucasian male with a history of RLQ abdominal pain, nausea, vomiting and anorexia from 15 days ago referred to surgery ward. Ultrasound showed a hypoachoic lesion with diameters 50 mm × 70 mm in RLQ of abdomen and a round echogenic area in right lobe of liver with diameter 15 mm. The findings were revealed an abscess located in right iliac fossa then local drainage of abscess was performed. Four days later the patient was re-admitted because of severe abdominal distention and lack of bowel movement. Laparoscopy was performed before proceeding with further examinations, due to the poor general condition of the patient. The sigmoid was adherent into the abdominal wall and mild intestinal loop distention and apple-core view was observed during operation. Cancer of sigmoid complicated by a right iliac fossa abscess was diagnosed and Hartman colestomy was undertaken. At the last follow-up examination 3 months after operation, the patient was in good health with no clinical evidence of recurrence.

关键词：脓肿结肠病例报告腺癌穿孔操作过程健康状况大肠癌

Study the Role of Maritime Energy Management in Achieving the United Nations Sustainable Development Goals (UN SDGs), in particular, Goal 7, in Oman Maritime Community

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Sustainable Marine Structures 2020年第2期2卷 1-12页

作者： Hamid reza soltani Motlagh Department of Maritime Engineering International Maritime College of Oman(IMCO)SuharOman

Sustainability is a concept for achieving integration and balance in development to preserve and use resources properly by providing new solutions to overcome structural,social and economic misconceptions to prevent further degradation and waste of natural resources and create a better future for human *** development can be defined as a strategy for the correct use of resources,by modifying and redefining consumption patterns and avoiding one-sided development ***,sustainable development is defined as a long-term and unlimited solution for aligning different concepts(social,economic,and environmental),seemingly independent but related and influencing each *** paper examines the challenges and capacities of the Oman Maritime Community and Maritime Energy Management's role in terms of sustainable *** analyze this issue,the role of key players in Oman's maritime industry,such as the Oman Fisheries Company and the Oman Shipping Company,has been studied with the five main indicators of sustainable development goals,including people,the planet,peace,welfare,and partnership.

关键词： Sustainable development Maritime energy Maritime community Oman maritime Energy management UNSDGS Development goals

On the prediction of geochemical parameters(TOC,S1 and S2)by considering well log parameters using ANFIS and LSSVM strategies

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Petroleum 2022年第2期8卷 174-184页

作者： Danial Ahangari reza Daneshfar Mohammad Zakeri Siavash Ashoori Bahram soltani Soulgani Department of Petroleum Engineering Petroleum University of TechnologyAhwazIran Department of Geology Faculty of Earth SciencesS.Chamran University of AhwazIran

Geochemical parameters are useful properties to enhance hydrocarbon exploration ***,attaining these parameters,for instance total organic carbon(TOC),volatile and residual hydrocarbon(S1&S2)is a challenge for geologists due to the high cost and time ***,addressing this issue has become an interesting subject for many *** a result,on the ground of conventional well logs,vast kinds of methods,for example,back propagation artificial neural network(BPANN),have been introduced to solve this *** these kinds of methods brings scientists tremendous amounts of information related to the richness of organic matter in a ***,the precision of the aforementioned method is inadequate and BPANN is affected negatively by local ***,current study cope with this issue and alleviate the uncertainty,Least Squares Support Vector Machine(LSSVM)and Adaptive-Neuro Fuzzy Inference System(ANFIS)algorithms cooperating with the particle swarm optimization(PSO)were suggested as a suitable method to increase the precision of estimating geochemical *** data bank for this research was attained from available sources of Shahejie formation from Bohai bay basin located in China,which consists of geochemical and well logging *** of this study illustrated that ANFIS-PSO and LSSVMPSO have a great ability to estimate geochemical *** values of R^(2) obtained for these two models in order to predict the output parameters of TOC,S_(1) and S_(2) are equal to 0.6846&0.785,0.6864&0.778,and 0.7343&0.8128,*** statistical comparison between these models shows that LSSVM-PSO shows a better performance compared to another ***,a new attempt was implemented to evaluate the impacts of input parameters on the outputs and the results of sensitivity analysis suggest that transit interval time had the greatest effect on the output parameters.

关键词： Least squares support vector machine Total organic carbon Well log parameters Adaptive-neuro fuzzy inference system Particle swarm optimization

湿度对旋转电机绝缘系统介电响应性能的影响规律

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国外大电机 2022年第4期 20-28页

作者： [加拿大]reza soltani 郑昌猛(译) 宋秀芝(译) 付强(校) 不详

1引言湿度是一个可能会对旋转电机绕组绝缘的介电性能(如绝缘电阻(IR)和极化指数(PI))产生很大影响的参数。由于潮湿污染,停机且没有空间加热器的电机,其绝缘电阻和极化指数的读数可能明显低于预期。根据美国电气和电子标准IEEE43-2000... 详细信息

1引言湿度是一个可能会对旋转电机绕组绝缘的介电性能(如绝缘电阻(IR)和极化指数(PI))产生很大影响的参数。由于潮湿污染,停机且没有空间加热器的电机,其绝缘电阻和极化指数的读数可能明显低于预期。根据美国电气和电子标准IEEE43-2000,在恢复电机运行或执行高压测试之前,应先将这些电机进行干燥处理,以获得符合标准要求的测试结果[1]。对于较旧的热塑性沥青云母片和虫胶云母片绝缘材料来说尤其如此,它们具有吸湿性(容易吸水),因此潮湿空气中的湿气可能会渗人绝缘体。

关键词：旋转电机绝缘电阻极化指数绝缘系统空间加热器高压测试电机运行潮湿空气