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Representation of Dynamic Positioning on Hovering Type Autonomous Underwater Vehicle in Precise Welding Operations

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Journal of Harbin Institute of Technology(New Series) 2021年第3期28卷 79-89页

作者： Araz Hamayeli Mehrabani reza hasanzadeh ghasemi Department of Engineering Hakim Sabzevari UniversitySabzevar ***Iran

This paper proposes dynamic positioning(DP) on a hovering autonomous underwater vehicle(HAUV) to perform accurate underwater processes such as welding operations. High maneuverability, high controllability, and hovering of the robot were the prerequisites of this operation, which increase its accuracy and velocity and reduce costs and human health risks. Other types of thrusters were used in this robot to reduce the number of thrusters and controller’s complexity. Controlling every 6 degrees of freedom to perform this type of operation was done. Furthermore, such a delicate operation required controlling the translational and rotational movements together. There was also a need to control the velocities to travel in a prescribed distance at a reasonable time. The possibility of dynamic positioning for welding and maintaining position at a point was defined for the robot. Then the robot’s performance under a defective state-servo motor failure, thruster malfunction-and the subsequent effects on the performance during the predetermined missions were investigated. Simulation results demonstrated that the HAUV has the capability to perform dynamic positioning operations. In this article, one of the prevalent classic control methods called PID controller was employed for controlling the movements of the robot.

关键词： HAUV dynamic positioning underwater welding

Outcomes of surgical correction of Peyronie’s disease with plaque excision and grafting: Comparison of testicular tunica vaginalis graft versus bovine pericardium graft

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Asian Journal of Urology 2024年第3期11卷 497-503页

作者： Ali Eslahi Faisal Ahmed Mohammad reza Askarpour Hossein-Ali Nikbakht Iman Shamohammadi Payam ghasemi Hanieh Alimardani Bahareh Ebrahimi Department of Urology School of MedicineShiraz University of Medical SciencesShirazIran Shiraz Geriatric Research Center Shiraz University of Medical SciencesShirazIran Urology Research Center Al-Thora General HospitalDepartment of UrologySchool of MedicineIbb University of Medical SciencesIbbYemen Social Determinants of Health Research Center Health Research InstituteBabol University of Medical SciencesBabolIran

Objective:Peyronie’s disease(PD)is an abnormal wound healing in the penile tunica *** fibrotic plaque excision,different graft materials have been used to repair the defects,but the optimal graft remains *** study aimed to compare the functional outcomes of testicular tunica vaginalis grafts and bovine pericardium grafts in patients with severe ***:A retrospective comparative study was conducted on 33 PD patients undergoing partial plaque excision and grafting from September 2015 to May *** patients were divided into two groups depending on the type of graft *** 15 patients in Group B,testicular tunica vaginalis grafts were used to repair the defect,while for 18 patients in Group A,bovine pericardium grafts were *** of the patient’s age,comorbidities,sexual function,penile curvature,postoperative complications,need for further treatment,change in penile length,and satisfaction were gathered and compared between the *** function was evaluated using the 5-item version of the International Index of Erectile Function(IIEF-5),and a functional less than 20-degree penile curvature after surgery was considered a successful ***:There was no difference in age,comorbidities,degree of curvature,perioperative IIEF-5,operative time,plaque size,or complication *** surgery,a statistically significant improvement in curvature degree(p<0.05)and satisfactory penile appearance(p<0.05)were seen in both groups without any superiority between the two groups(p=0.423 and p=0.840,respectively).With a 30-month follow-up,the IIEF-5 was consistent in both groups,with no statistical significance between the groups(p=0.492).The main change in penile length during the operation was increased and still positive in the last follow-up in both groups without statistical significance(p=0.255 and p=0.101,respectively).Conclusion:Partial plaque excision and corporoplasty with both testicular tunica vaginalis or bovine pericard

关键词： Peyronie's disease Plaqueexcision Testiculartunica vaginalis graft Bovinepericardium graft

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白内障手术候选者的眼部生物特征参数分析

国际眼科杂志 2024年第8期24卷 1186-1193页

作者： Zahra Sarlak Masoud Khorrami-Nejad Hamed ghasemi Ali Nouraeinejad reza Yousefi 伊朗德黑兰医科大学Farabi眼科医院转化眼科研究中心 *** 伊朗德黑兰医科大学康复学院视光系 ***

目的:分析白内障手术候选人的眼部生物特征参数。方法:横断面研究。纳入2017-01/2021-09就诊于伊朗德黑兰Farabi眼科医院的4607例白内障患者(4607眼)。使用IOLMaster 700评估眼轴(AL)、角膜曲率(Kf、Ks、Km)、前房深度(ACD)。根据AL分为... 详细信息

目的:分析白内障手术候选人的眼部生物特征参数。方法:横断面研究。纳入2017-01/2021-09就诊于伊朗德黑兰Farabi眼科医院的4607例白内障患者(4607眼)。使用IOLMaster 700评估眼轴(AL)、角膜曲率(Kf、Ks、Km)、前房深度(ACD)。根据AL分为22 mm25 mm组,根据ACD分为3.00 mm3.60 mm组。结果:患者平均年龄60.3±14.1(8-95)岁,女2243例(48.69%),男2364例(51.31%)。AL、ACD和平均角膜曲率范围分别为23.1-23.4 mm、3.1-3.2 mm和44.50-45.00 D。AL>25 mm组ACD平均值显著高于22 mm≤AL≤25 mm组和22 mm3.60 mm组的平均AL显著高于3.00 mm25 mm组的Kf、Ks、Km均值显著高于ACD>3.60 mm组和22 mm

关键词：白内障眼轴前房深度角膜曲率

Border-search and jump reduction method for size optimization of spatial truss structures

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 123-134页

作者： Babak DIZANGIAN Mohammad reza ghasemi Department of Civil Engineering Velayat UniversityIranshahr ***Iran Department of Civil Engineering University of Sistan and BaluchestanZahedan ***Iran

This paper proposes a sensitivity-based border-search and jump reduction method for optimum design of spatial *** is considered as a two-phase optimization approach,where at the first phase,the first local optimum is found by few analyses,after the whole searching space is limited employing an efficient random strategy,and the second phase involves finding a sequence of local optimum points using the variables sensitivity with respect to corresponding values of constraints *** reach the global solution at phase two,a sequence of two sensitivity-based operators of border-search operator and jump operator are introduced until convergence is *** analysis is performed using numerical finite difference *** do structural analysis,a link between open source software of OpenSees and MATLAB was *** truss problems were attempted for optimization in order to show the fastness and efficiency of proposed *** were compared with those reported in the *** shows that the proposed method is competitive with the other optimization methods with a significant reduction in number of analyses carried.

关键词： optimum design sensitivity analysis reduction method spatial tresses OpenSees

Reduced transition probabilities for 4He radiative capturereactions at astrophysical energies

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Research in Astronomy and Astrophysics 2014年第3期14卷 367-372页

作者： Hossein Sadeghi reza ghasemi Department of Physics Faculty of ScienceArak University

The reduced transition probabilities from an electric quadrupole B（E2） andreduced transition probabilities from a magnetic dipole B（M1） between the groundstate and the first excited state have been calculated for the 3He（α,γ）7Be, 8Be（α,γ）12cand 12C（α,γ）160 radiative capture reactions with the M3Y potential. These reactionsare important in stellar evolution. The calculated B（M1） and B（E2） for 7Be nuclei arefound to be 1.082 x 10-3 e2 fm2 and 1.921 e2 fma from transitions 3/2- to 1/2-, re-spectively. The obtained values for reduced transition probabilities B（E2） for the 12Cand 160 nuclei from transitions 0＋ to 2＋ are 12.54 e2 fm4 and 14.18 e2 fm4, respec-tively. The results are in satisfactory agreement with available experimental data.

关键词： nuclear reactions abundances methods: numerical

Performance of a novel bent-up bars system not interacting with concrete

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1301-1315页

作者： Aydin SHISHEGARAN Mohammad reza ghasemi Hesam VARAEE School of Civil Engineering Iran University of Science and TechnologyTehran 13114-16846Iran Structural Engineering Department of Civil EngineeringUniversity of Sistan and BaluchestanZahedan 98167-45845Iran Structural Engineering Ale Taha Institute of Higher EducationTehran 14888-36164Iran

Increasing the bending and shear capacities of reinforced concrete members is an interesting issue in structural *** recent years,many studies have been carried out to improve capacities of reinforced concrete members such as using post and pre-tensioning,Fiber Reinforced Polymer and other *** paper proposes a novel and significant technique to increase the flexural capacity of simply supported reinforced concrete *** proposed method uses a new reinforcement bar system having bent-up bars,covered with rubber *** technique will avoid interaction of bent-up bars with *** are located in the zone where compressive and tensile forces act against one anothe匚The compressive force in the upper point of the bent-up bars is exerted to the end point of these bars located under neutral ***,the tensile stress is decreased in reinforcements located under the neutral *** will cause the Reinforced Concrete(RC)beam to endure extra loading before reaching yield *** factors may well be considered as reasons to increase bending capacity in the new *** laboratory work together with finite element method analysis were carried out in this ***,bending capacity,ductility,strength,and cracking zone were assessed for the new proposed system and compared with the conventional *** the FEM simulation and the experimental test results revealed that the proposed system has significant impact in increasing the load bearing capacity and the stiffness of the RC *** the present study,an equation is formulated to calculate bending capacity of a new reinforcement bar system beam.

关键词： bending capacity rubber tube stress transfer bent-up bars ductility cracking

Simulation of clinker grinding circuits of cement plant based on process models calibrated using GA search method

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Journal of Central South University 2014年第2期21卷 799-810页

作者： A.Farzanegan E.ghasemi Ardi A.Valian V.hasanzadeh School of Mining College of EngineeringUniversity of Tehran Department of Mining Faculty of EngineeringUniversity of Kashan

Particle size distributions of obtained samples from several sampling campaigns were determined and raw data were mass balanced before being used in simulation *** determination of breakage function,selection function,Bond work index,residence time distribution parameters,and Whiten's model parameters for air separators and diaphragms between the two compartments of tube ball mills,performance of the circuits was simulated for given throughputs and feed particle size ***'s model parameters were determined by GA(genetic algorithm) toolbox of MATLAB *** on implemented models for modeling and simulation,optimization of circuits was carried *** increased nearly 10.5% and 15.8% in fresh feed capacity input to each tube ball *** addition,circulating load ratios of circuits are modified to 118% and 127% from low level of 57% and 22%,respectively,and also cut points of air separators are adjusted at 30 and 40 μm from high range of 53 and 97 μm,*** applications helped in well-operation and energy consumption reduction of equipments.

关键词： cement plant clinker grinding genetic algorithm simulation optimization

Brain tissue segmentation based on spatial information fusion by Dempster-Shafer theory

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第7期13卷 520-533页

作者： Jamal ghasemi Mohammad reza KARAMI MOLLAEI reza GHADERI Ali HOJJATOLESLAMI Signal Processing Laboratory Faculty of Electrical and Computer EngineeringBabol University of TechnologyP.O.Box 484BabolIran School of Computing University of KentCanterbury CT2 7PDUK

As a result of noise and intensity non-uniformity,automatic segmentation of brain tissue in magnetic resonance imaging (MRI) is a challenging *** this study a novel brain MRI segmentation approach is presented which employs Dempster-Shafer theory (DST) to perform information *** the proposed method,fuzzy c-mean (FCM) is applied to separate features and then the outputs of FCM are interpreted as basic belief *** salient aspect of this paper is the interpretation of each FCM output as a belief structure with particular focal *** results of the proposed method are evaluated using Dice similarity and Accuracy *** and quantitative comparisons show that our method performs better and is more robust than the existing method.

关键词： Magnetic resonance imaging (MR/) Segmentation Fuzzy c-mean (FCM) Dempster-Shafer theory (DST)

Assessment of different topographic correction methods in ALOS AVNIR-2 data over a forest area

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International Journal of Digital Earth 2013年第5期6卷 504-520页

作者： Nafiseh ghasemi Ali Mohammadzadeh Mahmod reza Sahebi Department of Photogrammetry&Remote Sensing Faculty of Geodesy and GeomaticsK.N.Toosi University of TechnologyTehranIran

Because the removal of topographic effects is one the most important preprocessing steps when extracting information from satellite images in digital Earth applications,the problem of differential terrain illumination on satellite imagery has been investigated for at least 20 *** there is no superior topographic correction method applicable to all areas and all images,a comparison of topographic normalization methods in different regions and images is *** this study,common topographic correction methods were applied on an ALOS AVNIR-2 image of a rugged forest area,and the results were evaluated through different *** results show that the simple correction methods[Cosine,Sun-Canopy-sensor(SCS),and Minnaert correction]are inefficient in exceptionally rough *** the improved correction methods(SCSC,modified Minnaert,and pixel-based Minnaert),the best result was achieved using a pixel-based Minnaert approach in which a separate correction factor in various slope angles is ***,this method should be considered for topographic correction,especially in forests with severe topography.

关键词： ALOS AVNIR-2 C Cosine digital earth forest Minnaert modified Minnaert pixel-based Minnaert SCS topographic correction