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Chinese Journal of Chemical Engineering 2016年第2期24卷 293-309页

作者： ali akbar jamali Shahrokh Shahhosseini Yaghoub Behjat School of Chemical Engineering Iran University of Science and Technology (IUST) Process Development and Equipment Technology Division Research Institute of Petroleum Industry

In this work, the effects of injecting an evaporating liquid jet into solid-gas flow are experimentally investigated. A new model （SHED model） and a supplementary model （spray model） have also been proposed to investigate some flow-field characteristics in three-phase fluidized bed with the mean relative error 4.3% between model and measured results. Some experiments were conducted to study the influences of flow-field parameters such as liquid volumetric flow rate, injection velocity, jet angle and gas superficial velocity as well as solid mass flux on the jet penetration depth （JPD）. In addition, independent variables were experimentally employed to propose two empirical correlations for JPD by using multiple regression method and spray cone angle （SCA） by using dimensional analysis technique. The mean relative errors between the JPD and SCA correlations versus ex- perimental data were 7.5% and 3.9%, respectively. In addition, in order to identify the variable effect, a parametric study was carried out. Applying the proposed model can avoid direct use of expensive devices to measureJPD and to nredict dronlet size.

关键词： FC-C riser reactor Hydrod ynamics Heterogeneous vaporization Jet penetration depth (JPD) Spray cone angle (SCA)

Experimental investigation of the effects of shrub filter strips on debris flow trapping and interception

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International Journal of Sediment Research 2023年第2期38卷 265-278页

作者： Songtang He Wenle Chen Daojie Wang Xiaoqing Chen Yuchao Qi Peng Zhao Yong Li Yongming Lin ali akbar jamali Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences Pipe China Southwest Pipeline Company Key Laboratory for Forest Ecosystem Process and Management College of Forestry Fujian Agriculture and Forestry University Department of GIS-RS and Watershed Management Maybod Branch Islamic Azad University

Ecological engineering plays an increasingly significant role in mountain hazard control, but the effect of species selection and arrangement(e.g., row spacing and stem spacing) on debris flow suppression is still unclear. To further understand the interception efficiency of shrub arrangement parameters on debris flow and explore the difference with slow hydraulic erosion, sixteen sets of small-scale flume experiments with different stem and row spacings were done to study the effects of shrubs on debris flow severity, flow rate, velocity, and particle size. The results suggest that, for a dilute debris flow, sediment interception effectiveness(27.4%-60.9%) decreases gradually as stem spacing increases. Moreover, as row spacing increases, flow velocity reduction(34.4%-44.9%) and flow reduction(18.5%-47.4%) gradually decrease; and the bulk density reduction(0.5%-5.3%) and sediment interception increase initially and then decrease. In contrast, for a viscous debris flow, the flow reduction, flow velocity reduction, and sedimentation interception decrease gradually as the stem spacing increases. As row spacing increases,the flow velocity reduction, flow reduction, and sediment interception all increase initially and then decrease. A formula for the flow velocity of dilute debris flow after the filter strip was derived based on the energy conservation law and Bernoulli’s equation, confirming that debris flow movement is closely related to the degree of vegetation cover. This research strengthens the current understanding of the effectiveness of vegetation in debris flow disaster prevention and control and can guide practical applications.

关键词： Ecological engineering Mountain hazards mitigation and prevention Shrub filter strips Debris flow Sediment trapping

Prevalence of retinal pathologies in people over 60 years:the Tehran Geriatrics Eye Study

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 721-728页

作者： Abolghasem Mortazavi alireza Hashemi alirerza jamali Hassan Hashemi Mohammadreza Aghamirsalim Mehdi Khabazkhoob Department of Neurosurgery Sina HospitalTehran University of Medical SciencesTehran ***Iran Noor Ophthalmology Research Center Noor Eye HospitalTehran ***Iran Rehabilitation Research Center Department of OptometrySchool of Rehabilitation SciencesIran University of Medical SciencesTehran ***Iran Noor Research Center for Ophthalmic Epidemiology Noor Eye HospitalTehran ***Iran Translational Ophthalmology Research Center Tehran University of Medical SciencesTehran ***Iran Department of Basic Sciences School of Nursing and MidwiferyShahid Beheshti University of Medical SciencesTehran ***Iran

AIM:To determine the prevalence of some retinal pathologies in people over 60y and their association with demographic and ocular ***:A cross-sectional study was conducted in Tehran using multistage cluster *** selecting subjects aged 60 and over,optometric,and ophthalmic examinations were *** retinal examination,a 90 D lens was used and indirect ophthalmoscopy was performed after instilling tropicamide *** was done using the IOL Master for all ***:Of 3791 people that were invited through cluster sampling,3310 participated in the study(response rate=82%).The prevalence of retinal pigmented epithelium(RPE)change,drusen,geographic atrophy(GA),hypertensive retinopathy(HTR),nonproliferative diabetic retinopathy(NPDR),proliferative diabetic retinopathy(PDR),choroidal neovascularization(CNV),central retinal artery occlusion(CRAO),myopic retinopathy(MR),branch retinal vein occlusion(BRVO),and central retinal vein occlusion(CRVO)was 27.42%,11.08%,4.52%,3.03%,4.05%,0.54%,0.82%,0.39%,0.20%,0.49%,and 0.19%,*** removing the effect of age,the odds of NPDR were 1.68 times higher in women compared to men(P=0.014).After removing the effect of sex,the odds of drusen,RPE change,GA,CNV,BRVO,and CRVO increased with ***:There is a higher prevalence of RPE change,drusen,GA,CNV and a lower prevalence of MR and CRAO in the elderly population of Tehran aged over 60y compared to global average *** the correlation of most of the diseases with age and their effects on vision,attention should be paid to these diseases and the related screening programs to prevent vision impairment.

关键词： retinal pathologies cross-sectional study vision impairment

基于多方位采集激光诱导击穿光谱的高温合金判别分析方法

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分析试验室 2024年

作者：张梦阳付洪波王华东杨彦红 Saifullah jamali 张志荣中国科学技术大学研究生院科学岛分院中国科学院合肥物质科学研究院安徽光学精密机械研究所光子器件与材料安徽省重点实验室中国科学院金属研究所师昌绪先进材料创新中心中国科学院合肥物质科学研究院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室国防科技大学先进激光技术安徽省实验室

高温合金是指以铁、镍、钴为基体，能在600 ℃以上高温及一定应力作用下长期工作的一类金属材料，在航空航天和能源领域具有重要应用价值，高温合金的在线原位判别对质量控制、生产监管、回收利用等具有重要意义。本研究采用多方位采集... 详细信息

高温合金是指以铁、镍、钴为基体，能在600 ℃以上高温及一定应力作用下长期工作的一类金属材料，在航空航天和能源领域具有重要应用价值，高温合金的在线原位判别对质量控制、生产监管、回收利用等具有重要意义。本研究采用多方位采集优化的激光诱导击穿光谱（LIBS）技术结合机器学习算法，对GH625，GF718，GH738，GH907，GH4141，GH4378，GH5188等7类共72块高温合金样品进行快速分类。每个样品随机选择5个分析位置，每个分析位置通过多方位采集装置获取200幅光谱。运用异常值剔除、滤波降噪和标准正态变量变换（SNV）对LIBS光谱数据进行预处理，并选取经主成分分析（PCA）降维后的前5个主成分，作为线性判别分析（LDA）、K近邻（KNN）和支持向量机（SVM）等分类模型的输入。结果表明，PCA-SVM模型的分类性能最优，其训练集准确度达到了100%，测试集数据分类准确度为99.048%。LIBS技术与PCA-SVM方法相结合是一种很有前途的对不同牌号高温合金样品进行分类和鉴定的方法。

关键词：激光诱导击穿光谱高温合金机器学习判别分析

应用电容电阻模型研究大型成熟油田井间连通性

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石油勘探与开发 2017年第1期44卷 130-136页

作者： jamali ali ETTEHADTAVAKKOL Amin Texas Tech University Lubbock TX 79409 USA

针对电容电阻模型在大型成熟油田应用时存在的问题,选用了生产井电容电阻模型(CRMP),提出了其在大型成熟油田的简化应用方法,并进行了实例分析。结合大型成熟油田的特征,给出了CRMP简化推导方法。通过优化求解方法缩短求解时间、提高收... 详细信息

针对电容电阻模型在大型成熟油田应用时存在的问题,选用了生产井电容电阻模型(CRMP),提出了其在大型成熟油田的简化应用方法,并进行了实例分析。结合大型成熟油田的特征,给出了CRMP简化推导方法。通过优化求解方法缩短求解时间、提高收敛速率,包括应用全局优化算法,计算CRMP目标函数的解析梯度向量及Hessian矩阵并应用于解算器中,进行参数缩放等,使CRMP可以应用于大型油田。通过逐步历史拟合可提高CRMP模拟结果的可靠性。实例分析结果表明,采用该方法得到的连通性分析结果与生产实际相符,验证了该方法的可靠性。根据CRMP模拟结果,可以有效分析注入井与其周围生产井的连通性,并进行相关分析,例如判断哪些注水井可以改注二氧化碳以及某二氧化碳注入井是否适宜注二氧化碳等。

关键词：电容电阻模型成熟油田井间连通性提高采收率

Experimental Testing of Cellular Construction Materials Containing Flax Particles

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Fluid Dynamics & Materials Processing 2023年第3期19卷 723-741页

作者： Hamadou-ali Mohamed Benazzouk Amar Haïkel Ben Hamed Arash jamali Laboratoire des Technologies Innovantes(UR-UPJV 3899)-UPJV Amiens80000France Plateforme de Microscopie Electronique-UPJV HUB de l’Energie80039Amiens

The feasibility of a sustainable non-autoclaved cellular concrete,based on flax vegetable co-products,for the production of usable specimen in the lightweight construction field,has been investigated *** produced specimen,containing various volume ratios of flax particles with respect to preformulatd Tradical PF70 lime binder of 0,1,and 2,were lightened by creating a porous structure in the matrix through the addition of 0.3%*** powder(able to react with calcium hydroxide from the binder and result in microscopic air-bubbles).Fresh and hardened specimen properties,including hydration,fresh density,porosity,hardened density,compressive and flexural strengths,toughness energy,and dry thermal conductivity at different temperatures,were assessed for varying flax-to-binder *** have shown that the addition of Aluminum powder leads to restrain the setting time delay of binder-based ***,the hardened material displays a significant decrease in specimen density,thereby resulting in a compressive strength level compatible with that required in the cellular construction materials *** also highlighted the ability of added flax to induce a change in the specimen from brittle to ductile ***,a high degree of thermal insulation can be achieved,which makes the cellular specimen based on flax particle suitable as insulated-bearing walls material.

关键词： Flax particles cellular concrete lightening porous structure physico-mechanical properties thermal conductivity

Optimal selection of annulus radius ratio to enhance heat transfer with minimum entropy generation in developing laminar forced convection of water-Al2O3 nanofluid flow

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Journal of Central South University 2017年第8期24卷 1850-1865页

作者： Siavashi Majid jamali Mohammad Applied Multi-Phase Fluid Dynamics Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran

Heat transfer and entropy generation of developing laminar forced convection flow of water-Al_2O_3 nanofluid in a concentric annulus with constant heat flux on the walls is investigated numerically. In order to determine entropy generation of fully developed flow, two approaches are employed and it is shown that only one of these methods can provide appropriate results for flow inside annuli. The effects of concentration of nanoparticles, Reynolds number and thermal boundaries on heat transfer enhancement and entropy generation of developing laminar flow inside annuli with different radius ratios and same cross sectional areas are studied. The results show that radius ratio is a very important decision parameter of an annular heat exchanger such that in each Re, there is an optimum radius ratio to maximize Nu and minimize entropy generation. Moreover, the effect of nanoparticles concentration on heat transfer enhancement and minimizing entropy generation is stronger at higher Reynolds.

关键词： nanofluid heat transfer enhancement forced convection entropy generation annulus radius ratio

A wavelet packet based method for adaptive single-pole auto-reclosing

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 1016-1024页

作者： Sadegh jamali Navid GHAFFARZADEH Centre of Excellence in Power Systems Automation and Operation Iran University of Science and Technology Tehran Iran

We present a new algorithm for adaptive single-pole auto-reclosing of power transmission lines using wavelet packet transform. The db8 wavelet packet decomposes the faulted phase voltage waveform to obtain the coefficients of the nodes 257, 259 to 262. An index is then defined from the sum of the energy coefficients of these nodes. By evaluating the index, transient and permanent faults, as well as the secondary arc extinction instant, can be identified. The significant advantage of the proposed algorithm is that it does not need a threshold level and therefore its performance is independent of fault location, line parameters, and operating conditions. Moreover, it can be used in transmission lines with reactor compensation. The proposed method has been successfully tested under a variety of fault conditions on a 400 kV overhead line of the Iranian National Grid using the Electro-Magnetic Transient Program (EMTP). The test results validated the algorithm’s ability in distinguishing between transient arcing and permanent faults and determining the instant of secondary arc extinction.

关键词： Adaptive auto-reclosing Arcing faults Permanent faults Transmission lines Wavelet packet transform

Microstructure and mechanical properties of AA6063 aluminum alloy wire fabricated by friction stir back extrusion(FSBE) process

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International Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 1005-1012页

作者： Ghasem jamali Salman Nourouzi Roohollah Jamaati Department of Materials Engineering Babol Noshirvani University of Technology

In the present work,the friction stir back extrusion(FSBE)process was used as a novel method for the fabrication of AA6063 aluminum alloy *** electron microscopy(SEM)equipped with energy dispersive spectroscopy(EDS),tensile and hardness tests were *** FSBE via the rotational speed of 475 r/min resulted in fine equiaxed grains,and the mean grain size decreased from 179.0μm to 15.5μm due to the occurrence of dynamic recrystallization(DRX).Heat generated by the FSBE changed the size and volume fraction of the Mg2Si precipitated *** minimum particle size and maximum volume fraction obtained in the sample were processed by rotational speeds of 475 and 600 r/min,*** 475-r/min sample had the maximum hardness value due to having the lowest grain size(i.e.,15.5μm)and the presence of many fine Mg2Si precipitates in the aluminum *** increasing rotational speed up to 600 r/min,the hardness decreased,owing to the growth of both grains and *** FSBE process with a rotational speed of 475 r/min increased the tensile strength(from 150 to 209 MPa)and ductility(from 21.0%to 30.2%)simultaneously.

关键词： aluminum alloys friction stir back extrusion microstructure mechanical properties

Encoder-Decoder Based LSTM Model to Advance User QoE in 360-Degree Video

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Computers, Materials & Continua 2022年第5期71卷 2617-2631页

作者： Muhammad Usman Younus Rabia Shafi Ammar Rafiq Muhammad Rizwan Anjum Sharjeel Afridi Abdul Aleem jamali Zulfiqar ali Arain Ecole Doctorale Mathematiques InformatiqueTelecommunicationde ToulouseUniversity Paul SabatierToulouse31330France School of Electronics and Information Northwestern Polytechnical UniversityXi’an710129China Department of Computer Science NFC Institute of Engineering and Fertilizer ResearchFaisalabad38000Pakistan Department of Electronic Engineering The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Electrical Engineering Sukkur IBA UniversitySukkur65200Pakistan Department of Electronic Engineering Quaid-e-Awam University of EngineeringScience and Technology(QUEST)Nawabshah67450Pakistan Department of Telecommunication Engineering MUETJamshoro76060Pakistan

The development of multimedia content has resulted in a massiveincrease in network traffic for video streaming. It demands such types ofsolutions that can be addressed to obtain the user’s Quality-of-Experience(QoE). 360-degree videos have already taken up the user’s behavior by ***, the users only focus on the part of 360-degree videos, known as aviewport. Despite the immense hype, 360-degree videos convey a loathsomeside effect about viewport prediction, making viewers feel uncomfortablebecause user viewport needs to be pre-fetched in advance. Ideally, we canminimize the bandwidth consumption if we know what the user motionin advance. Looking into the problem definition, we propose an EncoderDecoder based Long-Short Term Memory (LSTM) model to more accuratelycapture the non-linear relationship between past and future viewport positions. This model takes the transforming data instead of taking the direct inputto predict the future user movement. Then, this prediction model is combinedwith a rate adaptation approach that assigns the bitrates to various tiles for360-degree video frames under a given network capacity. Hence, our proposedwork aims to facilitate improved system performance when QoE parametersare jointly optimized. Some experiments were carried out and compared withexisting work to prove the performance of the proposed model. Last but notleast, the experiments implementation of our proposed work provides highuser’s QoE than its competitors.

关键词： Encoder-decoder based lSTM 360-degree video streaming LSTM QoE viewport prediction