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A Hybrid Particle Swarm Optimization and Genetic Algorithm for Model Updating of A Pier-Type Structure Using Experimental Modal Analysis

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China Ocean Engineering 2020年第5期34卷 697-707页

作者： Alireza MOJTAHEDI shahriar BAYBORDI Amin FATHI Aliakbar YAGHUBZADEHb Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz 51666-16471Iran Department of Maritime Engineering Amirkabir University of TechnologyTehranIran

Conventional design of pier structures is based on the assumption of fully rigid joints. In practice, the real connections are semi-rigid that cause changes in dynamic characteristics. In this study, quality of the joints is investigated by considering changes in natural frequencies. For this purpose, numerical and experimental modal analyses are carried out on related physical model of a pier type structure. When numerical results are evaluated,natural frequencies generally do not match the expected experimental results. Uncertainties in different aspects of engineering problems are always a challenge for researchers. The numerical models which are constructed on the basis of highly idealized scheme may not be able to represent all of the physical aspects of the physical one. For this study, determination of percentage of semi-rigid joints is considered as an optimization problem based on the numerical and experimental frequencies. Probabilistic sensitivity analysis is also used to determine the search space.A new technique of optimization problem is solved by a combination of smart particle swarm optimization(PSO)and genetic algorithms, and a complicated and efficient system for model updating process is introduced. It is observed that the hybrid PSO-Genetic algorithm is applicable and appropriate in model updating process. It performs better than PSO algorithm, considering the good agreement between theoretical frequencies and experimental ones,before and after model updating.

关键词： pier structure probabilistic sensitivity analysis hybrid PSO-Genetic algorithm dynamic characteristics

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A critical review on the developments of rock support systems in high stress ground conditions

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International Journal of Mining Science and Technology 2020年第5期30卷 555-572页

作者： Masoud Ghorbani Korosh shahriar Mostafa Sharifzadeh Reza Masoudi Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyangLiaoning 110819China Department of Mining and Metallurgical Engineering Curtin UniversityKalgoorlieWA 6430Australia

Extreme ground behaviour in high-stress rock masses such as rockburst prone and squeezing ground conditions are encountered in a range of underground projects both in civil and mining *** occurrence of such ground behaviour types are difficult to predict and special design and construction measures must be taken to control *** the most appropriate support system in such grounds is one of the major challenges for ground control engineers because there are many contributing factors to be considered,such as the rock mass parameters,the stress condition,the type and performance of the support systems,the condition of major geological structures and the size and geometry of the underground *** main characteristics and support requirements of rockburst-prone and squeezing ground conditions are herein critically reviewed and characteristics of support functions are *** types of energy-absorbing rockbolts and other support elements applicable for ground support in burst-prone and squeezing grounds are *** differences in the choice and economics of ground support strategies in high-stress ground conditions between civil tunnels and mining excavations are *** support benchmarking data and mitigation measures for mines and civil tunnels in burst-prone,squeezing and heavily swelling grounds conditions are briefly presented by some examples in practice.

关键词： High in-situ stress Rockburst Squeezing Swelling Energy-absorbing rockbolts Yielding supports

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Colonoscopic evaluation of minimal rectal bleeding in average-risk patients for colorectal cancer

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World Journal of Gastroenterology 2008年第42期14卷 6536-6540页

作者： shahriar Nikpour Ali Ali Asgari Department of InternalMedicine Loghman Hakim Hospital Shaheed BeheshtiUniversity of Medical Sciences Tehran Iran

AIM: To assess the prevalence of clinically signifi cant lesions in patients with minimal bright red bleeding per rectum (BRBPR). METHODS: Consecutive outpatients prospectively underwent colonoscopy at Loghman Hakim Hospital, Tehran. Minimal BRBPR was defi ned as small amounts of red blood after wiping or in the toilet bowl. Patients with the following alarm signs were excluded: Positive personal history of colorectal neoplasms or inflamma-tory bowel disease (IBD), positive fi rst degree family history of colorectal neoplasms, history of altered bow- el habits, recent signifi cant weight loss, and presence of iron defi ciency anemia. Neoplastic polyps, colorectal carcinoma, and IBD were def ined as signif icant lesions. RESULTS: A total of 402 patients (183 female and 219 male, aged 43.6 ± 15.7 years) were studied. Hemorrhoids (54.2%), anal fi ssures (14.2%) and ul-cerative colitis (14.2%) were the most common lesions and colonoscopy was normal in 8.0%. Signifi cant le-sions were found in 121 (30.1%) patients, including 26 patients (6.5%) with adenocarcinoma and 30 (7.5%) with adenomatous polyps. Almost all patients with signifi cant lesions had at least one lesion in the distal colon; an adenocarcinoma and an adenomatous polyp in the proximal colon were found in 2 patients with hemorrhoids. CONCLUSION: Flexible sigmoidoscopy appears to be sufficient for the evaluation of average risk patients with minimal BRBPR. Rigid sigmoidoscopy may be used as an alternative in patients less than 40 years of age in settings where the former is not available. Thechoice of colonoscopy over flexible sigmoidoscopy in patients aged over 50 years should be individualized.

关键词： Gastrointestinal hemorrhage Colonoscopy Colorectal neoplasms Inflammatory bowel disease

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Temperature-dependent development of Neoseiulus barked （Acari： Phytoseiidae） on Tetranychus urticae （Acari： Tetranychidae） at seven constant temperatures

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Insect Science 2012年第2期19卷 220-228页

作者： shahriar Jafari Yaghoub Fathipour Farid Faraji Department of Entomology Faculty of Agriculture Tarbiat Modares University Tehran Iran MITOX Consultants Amsterdam The Netherlands

The effect of seven constant temperatures of 15, 20, 25, 27, 30, 35 and 37℃ on developmental time ofNeoseiulus barkeri Hughes were determined in laboratory conditions under 65% - 5% RH and a photoperiod of 12 ： 12 （L ： D） h on nymphal stages of Tetranychus urticae Koch. Total developmental time of females （from egg to adult emergence） at the above-mentioned temperatures was 26.59, 14.43, 6.32, 5.64, 4.59, 3.98 and 4.67 days, respectively. Developmental rate of the N. barkeri increased as temperature increased from 15 to 35℃, but declined at 37℃. A linear and two nonlinear models were fitted to developmental rate of immature stages ofN. barkeri to predict the developmental rate as a function of temperature, as well as to estimate the thermal constant （K） and critical temperatures （i.e., Tmin, Topt and Tmax）. The estimated values of the Tmin and K for total developmental time using the linear model were 12.07℃ and 86.20 degree-days （DD）, respectively. The Trnin and Tmax estimated by the Sharpe-Schoolfield-Ikemoto （SSI） model were 11.90℃ and 37.41℃, respectively. The estimated Topt for overall immature stage development ofN. barkeri by the Lactin and SSI models were 33.89℃ and 24.51℃, respectively. Based on the biological criteria of model evaluation, the linear and SSI models were found to be the best models for describing the developmental rate of overall immature stages of N. barkeri and estimating the temperature thresholds.

关键词： Neoseiulus barkeri temperature thresholds temperature-dependent development Tetranychus urticae thermal constant

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Correlations between various rock mass classification/characterization systems for the Zagros tunnel-W Iran

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Journal of Mountain Science 2020年第7期17卷 1790-1806页

作者： shahriar SADEGHI Ebrahim SHARIFI TESHNIZI Benyamin GHOREISHI Department of Geology Faculty of scienceImam Khomeini International UniversityQazvin34149-16818Iran Engineering Geology Young Researchers and Elite ClubShahrekord BranchIslamic Azad UniversityShahrekord15655-461Iran

This study deals with the comparative investigation on various classification/characterization systems for sedimentary rocks in two parts,40 kmlong of the Zagros tunnel,west of *** results of extensive geotechnical explorations and field measurements were applied to obtain the rock mass classification/characterization systems such as Rock Mass Rating(RMR),Rock Condition Rating(RCR),Q-system(Q),Rock Mass Number(QN),Rock Mass index(RMi),Rock Structure Rating(RSR),and Geological Strength Index(GSI)for a wide range of sedimentary rocks.A set of systems inter-relationship is *** of these correlation relations such as RMR-Q,RMR-RMi,RMi-Q,RCR,GSI-GSI(Cai)are similar to the one or more relations proposed in the previous studies,however,some of them such as RSR-RMR,RSR-Q,RCR-QN and GSI-RMR are not similar to the previous *** set orientation and joint set number are more important parameters that cause weak correlation coefficients where both side classifications are not similar in considering them in calculating *** it is proposed to find relations between any pairs of systems that both of them consider or not consider these *** relations are proposed for a wide range of sedimentary rocks and can be applied for similar geological environments.

关键词： Rock mass dassification/characterization systems Zagros Tunnel Sedimentaiy rocks

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Optimization of the fully grouted rock bolts for load transfer enhancement

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International Journal of Mining Science and Technology 2015年第5期25卷 707-712页

作者： Ghadimi Mostafa shahriar Korosh Jalalifar Hossein Department of Mining Engineering Tehran Science and Research BranchIslamic Azad University Faculty of Mining Metallurgy and Petroleum EngineeringAmir Kabir University of Technology Department of Petroleum and Mining Engineering Environmental and Energy Research CenterShahidBahonar University of Kerman

The purpose of this study is to investigate the role of bolt profile configuration in load transfer capacity between the bolt and ***,five types of rock bolts are used with different *** rock bolts are modeled by ANSYS *** show that profile rock bolt T_3 and T_ with load capacity 180 and 195 kN in the jointed rocks,are the optimum ***,the performances of the selected profiles are examined in Tabas Coal Mine by FLAC *** is good subscription between the results of numerical modeling and instrumentation reading such as tells tale,sonic extensometer and strain gauge rock *** to the finding of this study,the proposed pattern of rock bolts,on 7 + 6 patterns per meter with 2 flexi bolt(4 m) for support gate road.

关键词： Fully grouted rock bolts Numerical modeling Load transfer Bolt profile

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Micro-seeding and soft template effects on the control of polymorph and morphology of HMX micro particles in solvent-antisolvent process

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Defence Technology（防务技术） 2017年第6期13卷 392-396页

作者： Sajjad Damiri shahriar Namvar Hadi Panahi Department of Applied Chemistry Maleke-ashtar University of TechnologyShahin-shahrEsfahanIran

A seeding strategy was developed in the preparation of cyclotetramethylenetetranitramine(HMX)explosive micro-particles by solvent-antisolvent method, to control their polymorphs from dangerous gamma(y) type to the desired and standard beta(β) form with the size distribution of <10.0 μm, by using a low concentration of β-HMX fine particles as micro-seed in the antisolvent medium. All products were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and dynamic light scattering particle size analyzer. In the next step, the effective factors on the sizes and morphologies of micro-particles in the presence and absence of two soft templates of poly(ethylene glycol)-400(PEG-400) polymer and coconut fatty acid diethanolamide(lauramide) surfactant were investigated. The results of experiments showed that using of water-soluble PEG-400 in the low antisolvent temperatures leads to the production of very spherical particles. Also non-ionic surfactant of lauramide, direct the crystal growth to needle-like structures. The advantages of this method are its capability for the simple production of β-HMX micro-particles in the large scale production process, with the various crystal structures and particles size distributions.

关键词： Micro seeding Polymorph HMX Explosive Micro-particle Solvent-antisolvent process

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Selection of Fe as a barrier for manufacturing low-cost MgB2 multifilament wires-Advanced microscopy study between Fe and B reaction

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Journal of Magnesium and Alloys 2024年第7期12卷 2783-2792页

作者： Hao Liang Dipak Patel Ziming Wang Akiyoshi Matsumoto Matt Rindfleisch Micheal Tomsic Richard Taylor Fang Liu Yusuke Yamauchi md.shahriar A Hossain School of Mechanical and Mining Engineering The University of QueenslandSt LuciaQueensland 4072Australia The Commonwealth Scientific and Industrial Research Organisation(CSIRO) LindfieldNew South Wales 2070Australia University of Science and Technology of China Hefei 230026China Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China National Institute for Materials Science(NIMS) 1-2-1 SengenTsukubaIbaraki 305-0047Japan Hyper Tech Research Inc.539 Industrial Mile RdColumbusOH 43228USA Applied Superconductivity Laboratory Queensland University of TechnologyBrisbaneQueensland 4001Australia Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityNagoya 464-8603Japan Australian Institute for Bioengineering and Nanotechnology(AIBN) The University of QueenslandSt LuciaQueensland 4072Australia Department of Chemical and Biomolecular Engineering Yonsei University50 Yonsei-roSeodaemun-guSeoul 03722South Korea

The high cost of using the niobium(Nb)barrier for manufacturing magnesium diboride(MgB2)mono-and multi-filamentary wires for large-scale applications has become one of the barriers to replacing current commercial niobium-titanium *** potential of replacing the Nb barrier with a low-cost iron(Fe)barrier for multifilament MgB2 superconducting wires is investigated in this ***,MgB2 wires with Fe barrier sintered with different temperatures are studied(from 650°C to 900°C for 1 h)to investigate the non-superconducting reaction phase of *** superconducting performance including engineering critical current density(Je)and n-value are tested at 4.2 K in various external magnetic *** best sample sintered at 650°C for 1 h has achieved a Je value of 3.64×10^(4) A cm^(−2) and an n-value of 61 in 2 T magnetic field due to the reduced formation of Fe2B,better grain connectivity and homogenous *** microstructural analysis,the focused ion beam(FIB)is utilised for the first time to acquire three-dimensional microstructures and elemental mappings of the interface between the Fe barrier and MgB2 core of different *** results have shown that if the sintering temperature can be controlled properly,the Je and n-value of the wire are still acceptable for magnet *** formation of Fe2B is identified along the edge of MgB2,as the temperature increases,the content of Fe2B also increases which causes the degradation in the performance of wires.

关键词： Superconducting wires MgB2 MRI magnet Engineering critical current density Fe2B

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Superconducting joints using reacted multifilament MgB_(2)wires:A technology toward cryogen-free MRI magnets

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Journal of Magnesium and Alloys 2024年第1期12卷 159-170页

作者： Dipak Patel Akiyoshi Matsumoto Hiroaki Kumakura Yuka Hara Toru Hara Minoru Maeda Hao Liang Yusuke Yamauchi Seyong Choi Jung Ho Kim md shahriar A.Hossain School of Mechanical and Mining Engineering The University of QueenslandSt LuciaQueensland 4072Australia National Institute for Materials Science(NIMS) 1-2-1 SengenTsukubaIbaraki 305-0047Japan Department of Electrical Engineering and Kangwon High Magnetic Field Center Institute of Quantum Convergence TechnologyKangwon National UniversityGangwon 24341Republic of Korea Australian Institute for Bioengineering and Nanotechnology(AIBN) The University of QueenslandSt LuciaQueensland 4072Australia Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityNagoyaAichi 464-8603Japan Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongNorth WollongongNew South Wales 2500Australia

The development of superconducting joining technology for reacted magnesium diboride(MgB_(2))conductors remains a critical challenge for the advancement of cryogen-free MgB_(2)-based magnets for magnetic resonance imaging(MRI).Herein,the fabrication of superconducting joints using reacted carbon-doped multifilament MgB_(2)wires for MRI magnets is *** achieve successful superconducting joints,the powder-in-mold method was employed,which involved tuning the filament protection mechanism,the powder compaction pressure,and the heat treatment *** fabricated joints demonstrated clear superconducting-to-normal transitions in self-field,with effective magnetic field screening up to 0.5 T at 20 *** evaluate the interface between one of the MgB_(2)filaments and the MgB_(2)bulk within the joint,serial sectioning was conducted for the first time in this type of superconducting *** serial sectioning revealed space formation at the interface,potentially caused by the volume shrinkage associated with the MgB_(2)formation or the combined effect of the volume shrinkage and the different thermal expansion coefficients of the MgB_(2)bulk,the filament,the mold,and the sealing *** findings are expected to be pivotal in developing MgB_(2)superconducting joining technology for MRI magnet applications through interface engineering.

关键词： Mg B2 superconducting joint MgB_(2)conductor MRI applications Cryogen-free magnet Persistent-mode operation

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Detection of Different Stages of Alzheimer’s Disease Using CNN Classifier

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Computers, Materials & Continua 2023年第9期76卷 3933-3948页

作者： S M Hasan Mahmud md Mamun Ali Mohammad Fahim shahriar Fahad Ahmed Al-Zahrani Kawsar Ahmed Dip Nandi Francis M.Bui Department of Computer Science American International University-Bangladesh(AIUB)Dhaka1229Bangladesh Centre for Advanced Machine Learning and Applications(CAMLAs) DhakaBangladesh Department of Software Engineering Daffodil International UniversityDhakaBangladesh Department of Computer Engineering Umm Al-Qura UniversityMecca24381Saudi Arabia Department of ECE University of SaskatchewanSaskatoonSK S7N5A9Canada Group of Biophotomatiχ Department of ICTMBSTUSantoshTangail1902Bangladesh

Alzheimer’s disease(AD)is a neurodevelopmental impairment that results in a person’s behavior,thinking,and memory *** common symptoms ofADare losingmemory and early *** addition to these,there are several serious impacts ***,the impact ofADcanbemitigatedby early-stagedetection though it cannot be cured ***-stage detection is the most challenging task for controlling and mitigating the impact of *** study proposes a predictive model to detect AD in the initial phase based on machine learning and a deep learning approach to address the *** build a predictive model,open-source data was collected where five stages of images of AD were available as Cognitive Normal(CN),Early Mild Cognitive Impairment(EMCI),Mild Cognitive Impairment(MCI),Late Mild Cognitive Impairment(LMCI),and *** stage of AD is considered as a class,and then the dataset was divided into three parts binary class,three class,and five *** this research,we applied different preprocessing steps with augmentation techniques to efficiently *** integrates a random oversampling technique to handle the imbalance problem from target classes,mitigating the model overfitting and *** three machine learning classifiers,such as random forest(RF),K-Nearest neighbor(KNN),and support vector machine(SVM),and two deep learning methods,such as convolutional neuronal network(CNN)and artificial neural network(ANN)were applied on these *** analyzing the performance of the used models and the datasets,it is found that CNN with binary class outperformed 88.20%*** result of the study indicates that the model is highly potential to detect AD in the initial phase.

关键词： Alzheimer’s disease early detection convolutional neural network data augmentation random oversampling machine learning

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