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Ultrafine and fine particle emission in turning titanium metal matrix composite(Ti-MMC)

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Journal of Central South University 2019年第6期26卷 1563-1572页

作者： seyed ali niknam Masoud SABERI Jules KOUAM Ramin HASHEMI Victor SONGMENE Marek BALAZINSKI School of Mechanical Engineering Iran University of Science and TechnologyHengam St.Resalat SquareFehran 13114-16846Iran Department of Mechanical Engineering Ecole de Technologie Superieure (ETS)MontrealQCH3C 1K3Canada Department of Mechanical Engineering Polytechnique MontrealMontrealQCH3T 1J4Canada

Titanium metal matrix composite(Ti-MMC)has excellent features and capabilities which can be considered a potential candidate to replace commercial titanium and superalloys within an extensive range of products and industrial *** of the superior features in Ti-MMC,however,referring to several factors including high unit cost and existence of rigid and abrasive ceramic particles in the generated matrices of the work part,the Ti-MMC is grouped as extremely difficult to cut with a poor level of ***,adequate process parameters for machining Ti-MMCs under several lubrication methods are rarely ***,adequate knowledge of this regard is strongly *** machinability attributes,ultrafine particles(UFPs)and fine particles(FPs)have been selected as the main machinability attributes and the factors leading to minimized emission have been *** to experimental observations,despite the type of coating used,the use of higher levels of flow rate led to less UFPs,while no significant effects were observed on *** similar cutting conditions,higher levels of FPs were recorded under the use of uncoated ***,cutting speed had no significant influence on UFPs;nevertheless,it significantly affects the FPs despite the type of insert used.

关键词： metal matrix composites(MMCs) particle emission dust emission turning lubrication mode

An efficient hybrid evolutionary optimization algorithm based on PSO and SA for clustering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 512-519页

作者： Taher niknam Babak AMIRI Javad OLAMAEI ali AREFI Electronic and Electrical Engineering Department Shiraz University of TechnologyShirazIran Information Technology Department Islamic Azad University-Fars Science and Research BranchShiraz Iran Technical Engineering Department Islamic Azad University-South Tehran BranchTehran Iran Power Engineering Group Department of Electrical and Computer Engineering Tarbiat Modares UniversityTehran Iran

The K-means algorithm is one of the most popular techniques in clustering. Nevertheless, the performance of the Kmeans algorithm depends highly on initial cluster centers and converges to local minima. This paper proposes a hybrid evolutionary programming based clustering algorithm, called PSO-SA, by combining particle swarm optimization (PSO) and simulated annealing (SA). The basic idea is to search around the global solution by SA and to increase the information exchange among particles using a mutation operator to escape local optima. Three datasets, Iris, Wisconsin Breast Cancer, and Ripley's Glass, have been considered to show the effectiveness of the proposed clustering algorithm in providing optimal clusters. The simulation results show that the PSO-SA clustering algorithm not only has a better response but also converges more quickly than the K-means, PSO, and SA algorithms.

关键词： Simulated annealing (SA) Data clustering Hybrid evolutionary optimization algorithm K-means clustering Parti-cle swarm optimization (PSO)

Assessment of fracture process in forta and polypropylene fiber-reinforced concrete using experimental analysis and digital image correlation

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1633-1652页

作者： seyed Hamid KALali Hamid ESKANDARI-NADDAF seyed ali EMAMIAN Department of Civil Engineering Hakim Sabzevari UniversitySabzevar ***Iran

This paper aims to characterize the evolution of the fracture process and the cracking behavior in fortaferro(FF)and polypropylene(PP)fiber-reinforced concrete under the uniaxial compressive loading using experimental analysis and digital image correlation(DIC)on the surface *** this purpose,6 mix designs,including two FF volume fractions of 0.10%,and 0.20%and three PP volume fractions of 0.20%,0.30%,and 0.40%,in addition to a control mix were evaluated according to compressive strength,modulus of elasticity,toughness index,and stress–strain *** influence of fibers on the microstructural texture of specimens was analyzed by scanning electron microscope(SEM)*** show that FF fiber-reinforced concrete specimens demonstrated increased ductility and strength compared to PP *** results revealed that the major crack and fracture appeared at the peak load of the control specimen due to brittleness and sudden gain of large lateral strain,while a gradual increase in micro-crack quantity at 75%of peak load was observed in the fiber specimens,which thenbegan to connect with each other up to the final *** accuracy of the results supports DIC as a reliable alternative for the characterization of the fracture process in fiber-reinforced concrete.

关键词： fiber-reinforced concrete forta-ferro and polypropylene fiber fracture process cracking behavior digital image correlation

Numerical analysis of reactive turbulent flow in the thrust chamber of RD-108 engine rocket

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Defence Technology（防务技术） 2019年第4期15卷 565-575页

作者： seyed Reza Taghavi Mohammad ali Dehnavi ali Ghafouri Department of Chemical Engineering Imam Hossein Comprehensive University

Combustion chamber modeling and simulation of the liquid propellant engine with kerosene as fuel and liquid oxygen as an oxidizer in the turbulent flow field are performed by CFD *** flow is modeled as Single-phase in steady state and using RNG k-ε turbulence *** results are validated by experimental data of thrust,special impulse and combustion chamber *** comparing t.^wo reaction models of finite rate chemistry and frozen model with experimental data,it is concluded that finite rate chemistry has acceptable *** optimum value of equivalence ratio(oxidizer to fuel ratio)per reaction and operational parameters of the engine which maximize thrust and special impulse are determined.

关键词： Liquid propellant engine Computational fluid dynamics(CFD) Kerosene and oxygen Freeze model Finite rate chemistry model

Design feasibility of gamma camera without collimator based on specific arrangement of the detectors

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Nuclear Science and Techniques 2016年第4期27卷 120-126页

作者： Hossein Akbari-Lalimi seyed ali Shafiei Geriatric Care Research Center Rafsanjan University of Medical Sciences Department of Medical Physics Mashhad University of Medical Sciences Department of Physiology and Pharmacology School of Medicine Qom University of Medical Sciences

In gamma camera and single-photon emission computerized tomography, the collimator removes most photons. Here, a gamma camera without collimator utilizes a specific arrangement of detectors. Instead of bending beams(like a lens) or directing beams(by parallel hole collimator), changes are created in detectors' field of view(FOV), so that each detector's FOV looks different from others. Simulation proved this theory, with 98 detectors(2 cm 9 1.41 cm) arranged in a zigzag manner for Monte Carlo simulation. A radioactive source with energy of140 ke V was situated on the detectors' faces. Sixty projections, each 3(0 –179) apart, were simulated by Monte Carlo N-Particle(MCNP) 4C code, rotating detectors around a radioactive point. The band containing the radioactive source is clearly visible in each *** obtained after simulation in different projections were reconstructed, and point source location emerged correctly. Simulation of gamma camera with zigzag arrangement of detectors and MCNP-4C code demonstrated that one could string the space and determine radioactive source by image reconstruction without using collimators, solely through these special detectors' distribution.

关键词：探测器准直器 γ相机蒙特卡洛模拟计算机断层扫描单光子发射设计布置

Creep rupture assessment for Level-2 PSA of a 2-loop PWR： accounting for phenomenological uncertainties

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Nuclear Science and Techniques 2017年第8期28卷 117-125页

作者： Faramarz Yousefpour seyed Mohsen Hoseyni seyed Mojtaba Hoseyni seyed ali Hashemi Olia Kaveh Karimi Nuclear Science and Technology Research Institute TehranIran Young Researchers and Elite Club East Tehran BranchIslamic Azad University Tehran Iran

The Level-2 probabilistic safety assessment(PSA) of pressurized water reactors studies the possibility of creep rupture for major reactor coolant system components during the course of high pressure severe accident sequences. The present paper covers this technical issue and tries to quantify its associated phenomenological uncertainties for the development of Level-2 PSA. A framework is proposed for the formal quantification of uncertainties in the Level-2 PSA model of a PWR type nuclear power plant using an integrated deterministic and PSA approach. This is demonstrated for estimation of creep rupture failure probability in station blackout severe accident of a 2-loop PWR, which is the representative case for high pressure sequences. MELCOR 1.8.6 code is employed here as the deterministic tool for the assessment of physical phenomena in the course of accident. In addition, a MATLAB code is developed for quantification of the probabilistic part by treating the uncertainties through separation of aleatory and epistemic sources of *** probability for steam generator tube creep rupture is estimated at 0.17.

关键词：模型不确定性蠕变断裂 PSA 压水堆断裂评价二级现象学反应堆冷却剂系统

Human microbiome and prostate cancer development:current insights into the prevention and treatment

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Frontiers of Medicine 2021年第1期15卷 11-32页

作者： Solmaz Ohadian Moghadam seyed ali Momeni Uro-Oncology Research Center Tehran University of Medical SciencesTehranIran

The huge communities of microorganisms that symbiotically colonize humans are recognized as significant players in health and *** human microbiome may influence prostate cancer *** date,several studies have focused on the effect of prostate infections as well as the composition of the human microbiome in relation to prostate cancer *** studies suggest that the microbiota of men with prostate cancer significantly differs from that of healthy men,demonstrating that certain bacteria could be associated with cancer development as well as altered responses to *** healthy individuals,the microbiome plays a crucial role in the maintenance of homeostasis of body *** may contribute to the emergence of health problems,including malignancy through affecting systemic immune responses and creating systemic inflammation,and changing serum hormone *** this review,we discuss recent data about how the microbes colonizing different parts of the human body including urinary tract,gastrointestinal tract,oral cavity,and skin might affect the risk of developing prostate ***,we discuss strategies to target the microbiome for risk assessment,prevention,and treatment of prostate cancer.

关键词： microbiome prostate cancer prevention treatment molecular pathological epidemiology(MPE) biomarker

Ce-promoted Mn/Na_2 WO_4/SiO_2 catalyst for oxidative coupling of methane at atmospheric pressure

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Journal of Natural Gas Chemistry 2010年第1期19卷 47-53页

作者： seyed Mehdi Kamali Shahri ali Nakhaei Pour Research Institute of Petroleum Industry (RIPI) National Iranian Oil Company P. O. Box 18745-4163 Tehran Iran

A series of Ce-promoted Mn-Na2WO4/SiO2 catalysts were prepared by incipient wetness impregnation method, and their catalytic performance for oxidative coupling of methane （OCM） was investigated at atmospheric pressure in a micro-quartz-tube reactor. The catalysts were characterized by X-ray diffraction （XRD）, temperature program reduction （TPR） and BET surface area. Ce promoter increased surface area and Na2WO4 species dispersion, which enriched the amount of the surface species. In addition, Ce promoter increased the Na/W species reduction, but the reduction peak shifted to higher temperature. Stability test of 5wt%Ce catalyst indicated suitable performance and stability. The selectivity and yield of C^2＋ hydrocarbons after 50 h operation reached 65.5% and 19.6%, respectively, at 840 ℃ over 5wt%Ce-2wt%Mn5wt%Na2WO4/SiO2 catalyst.

关键词： oxidative coupling of methane CeO2 promoter Mn/Na2WO4/SiO2

A Multi-Objective Multi-Period Model for Humanitarian Relief Logistics with Split Delivery and Multiple Uses of Vehicles

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Journal of Systems Science and Systems Engineering 2020年第3期29卷 360-378页

作者： Maliheh Khorsi seyed Kamal Chaharsooghi ali Bozorgi-Amiri ali Husseinzadeh Kashan Industrial Engineering Faculty of Industrial&Systems EngineeringTarbiat Modares UniversityTehranIran School of Industrial Engineering College of EngineeringUniversity of TehranTehranIran

Disaster relief logistics is a significant element in the management of disaster relief *** this paper,the operational decisions of relief logistics are considered in the distribution of resources to the affected areas to include scheduling,routing,and allocation *** proposed mathematical model simultaneously captures many aspects relevant to real life to face the challenging situation of *** such as multiple uses of vehicles and split delivery allow for better use of vehicles as one of the primary resources of disaster response.A multi-period multi-criteria mixed-integer programming model is introduced to evaluate and address these *** model utilizes a rolling horizon method that provides possibilities to adjust plans as more information becomes *** objectives of efficiency,effectiveness,and equity are jointly *** augmented epsilon constraint method is applied to solve the model,and a case study is presented to illustrate the potential applicability of our *** results show that the model is capable of generating efficient solutions.

关键词： Disaster management relief logistics vehicle routing problem multi-trip rolling horizon