MULTI-OBJECTIVE OPTIMIZATION DESIGN OF ROADHEADER’S CUTTING HEAD BASED ON THE GA by ZHAO LiJuan, FAN JiaYi

“…In order to improve the dynamic reliability of the roadheader,the roadheader’s rigid-flexible coupled model was established based on virtual prototyp,dynamic reliability analysis was done on the rotary table of different structural parameters,evaluation function was established based on mechanical optimization design theory,the function’s design variables was half cone angle,helix Angle and cutting line spacing, the function’s objective function was the minimization of maximum equivalent stress as the objective function.The cutting head’s optimal structural parameters was obtained by genetic algorithm.Based on the cutting productivity and rotary table equivalent stress, the optimal yawing speed was obtained by optimized multi-objective.The results shows that after two optimizations,rotary table maximum stress is decreased 18.495 MPa,the fatigue life is improved from 3.067 E4 to 3.326 E6,productivity is improved 18.6 t/h,prediction error is less than 1.3%,meet the design requirement.This method provides data support for the structure and kinematic parameters of cutting head,provides a new method for the optimization design of heavy complicated mechanical equipment.…”
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Theoretical background of the operating parameters of the satellite working mechanism of the hydraulic positive displacement machine by Pawel Sliwinski

“…A new mathematical formula for calculating the instantaneous geometric working volume as a function of the angle of rotation of the shaft (rotor) has been proposed. …”
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Crack initiation at V-notch tip subjected to in-plane mixed mode loading: An application of the fictitious notch rounding concept by F. Berto

“…The fictitious notch radius is determined as a function of the real notch radius the microstructural support length and the notch opening angle. …”
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Improving long‐tail classification via decoupling and regularisation by Shuzheng Gao, Chaozheng Wang, Cuiyun Gao, Wenjian Luo, Peiyi Han, Qing Liao, Guandong Xu

“…Existing methods mainly tackle this problem by reweighting the loss function or rebalancing the classifier. However, one crucial aspect overlooked by previous research studies is the imbalanced feature space problem caused by the imbalanced angle distribution. …”
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Optimal design of the cable metro with unified intermediate supports by Lagerev A.V., Lagerev I.A.

“…Synchronous change in the optimal values of the height and step of the installation of intermediate supports, depending on the angle of the longitudinal slope of the sur-face relief leads to the fact that the optimal cost characteristics of the cable metro lines are smooth functions. …”
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Mechanism Kinematics Analysis of Two-leg Shield Hydraulic Support by Wang Hongwei, Dong Zhifeng

“…As a multi-linkage mechanism with multi-degree of freedom,the two-leg shield hydraulic support is comprised of beams,fore and rear links and hydraulic cylinders.It can realize supporting roof,protecting coal wall and moving forward under the function of hydraulic power,and plays an important role in coal mining.According to structure and operating characteristics of the two-leg shield hydraulic support,the geometrical relationship and calculations about rear link angle and shield beam angle for the supporting height,head distance,leg length and balance cylinder length are deduced.The differential equation of motion for the hydraulic support is established by the Lagrangian theory,and the support type of ZY17300/32/70 is calculated and analyzed.The relationship between angle displacement and velocity for the rear link angle and shield beam angle along with the motion characteristic of supporting height is obtained.The response characteristics of motion velocity and acceleration for top beam are discussed during the working process of lifting up and down.…”
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A Satellite-Based Sky Luminance Model for the Tropics by Serm Janjai

“…The model is mathematically expressed as a multiplication of two functions. These are φ, which is a function of the zenith angle of a sky element and solar zenith angle, and f, which is a function of the angle between the sky element and the sun. …”
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MESHING PERFORMANCE ANALYSIS OF FACE ROLLER ENVELOPING HOURGLASS WORM DIRVE by WANG XuDong, LIU ZaiXin, LI LingYu

“…The equations of worm gear meshing function, meshing equation, lubrication angle, self rotation angle, induced normal curvature and relative entrainment velocity are derived. …”
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基于MATLAB的三轮式轻质车转向机构的优化设计 by 朱洪林, 吴小平

“…Based on the three-type light vehicle’s features and Ackerman steering angle,and the bottom of the foot and the steering linkage steering arm length be designed as variables.Then call the optimization function in MATLAB toolbox to optimize the design.Finally,the front wheel steering angle and theoretical optimization results is very close to Ackerman angle,and the steering mechanism be created in ADAMS for dynamic three-dimensional model simulation results,the results proved it is effective and the optimal goal is achieved.…”
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Superconductivity and special symmetry of twisted tri-layer graphene in chiral model by Yuri P. Rybakov, Medina Umar

“…To check the superconductor behavior of this system, the interaction with the external magnetic field \(B_0\) oriented along the graphene sheets is switched on and the internal magnetic intensity in the center is calculated as the function of the twisting angle. Vanishing of this function, due to the Meissner effect, being the important feature of the superconductivity, the corresponding dependence of the magic twisting angle on \(B_0\) is calculated. …”
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DESIGN AND STUDY A NEW TELESCOPIC ARM USED IN NARROW SPACE by LIU XiangYong, LI WanLi, WANG WenJia

“…As it is difficult to check water pumps and fuel boiler pipes,design and study a telescopic boom used in narrow space.Adopt steel tape to design telescopic arm,and the tapes’ edges are welded to form mechanical arm.Motor drive the divided wheel by gears,divided wheel drive steel tape to stretch,and telescopic boom has curly storage function.The arm’s section parameters include thickness,central angle,arc length;By the thin shell theory,analyze and calculate the central angle.Based on the Workbench software,analyze the central angle and thickness’ s infiuences to X and Y direction deformation.Results show that with the increase of central angle,the Y direction deformation decreases gradually,and the X direction deformation increases gradually.Deformation rate changes quickly before 40 °,and changes slowly after 40 °.With the increasement of thickness,the X and Y direction’s deformation rate are smaller.Based on theory and simulation,the final thickness is 0.1 mm and the central angle is 45 °.Finaly through experiments,verify the arm’s section parameters and bearing capacity.…”
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Multi-Dimensional Motion Parameter Estimation of a Rotating Object Based on Orbital Angular Momentum by Bowen He, Kun Tang, Guiping Jin, Yuehui Cui

“…A weighted iterative gradient algorithm is then applied to solve this function, ultimately obtaining the inclination angle. …”
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Research on Force-Saving Mechanism of Cutting Tool with Variable Curvature Directrix Rake Face Configuration by Feng Xie, Huawei Wei, Xiaofeng Chen, Chao Lei

“…Through the analysis of the working rake angle and shear angle of the tool with variable curvature directrix configuration rake face, the relationship between the parameters of the variable curvature directrix function and the working rake angle, and shear angle has been obtained. …”
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Phase Current Equalization Method of IPMSM-Based on-Board Boost Converter for Electric Vehicles by Yunkyung Hwang, Jaehong Kim, Minhyeok Lee, Juwon Choi, Kwanghee Nam

“…In this study, the complete IPMSM inductance model is utilized to obtain an analytical representation of the current ripple as a function of the switching duty and rotor angle. Based on this, the maximum charging current is estimated and the maximum charging power is also derived as a function of the rotor angle. …”
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3D channel modeling and space-time correlation analysis for V2V communications by Wenbo ZENG, Yigang HE, Bing LI, Guolong SHI, Feng ZHAO

“…To match complex wireless propagation scenarios,an improved 3D geometry-based stochastic model was proposed for vehicle to vehicle (V2V) communications channel.The exact relationship between the azimuth angle and elevation angle was taken into account and the corresponding space–time correlation function and space–Doppler power spectral density were derived,and the influence of important factors was analyzed.The observations and conclusions show that correlation characteristics is closely related to distribution of the scatterers and the angle of the antenna array under the non-isotropic scattering environment and is affected by the elevation angle of the antenna array under the isotropic scattering environment.And the space-time correlation characteristics in high vehicular traffic density is significantly lower than that in low vehicular traffic density.The corresponding simulation model is also derived by using a reasonable parameter calculation method.The simulation results validate the rationality of proposed model.It greatly improves analysis and simulation efficiency of V2V MIMO system.…”
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3D channel modeling and space-time correlation analysis for V2V communications by Wenbo ZENG, Yigang HE, Bing LI, Guolong SHI, Feng ZHAO

“…To match complex wireless propagation scenarios,an improved 3D geometry-based stochastic model was proposed for vehicle to vehicle (V2V) communications channel.The exact relationship between the azimuth angle and elevation angle was taken into account and the corresponding space–time correlation function and space–Doppler power spectral density were derived,and the influence of important factors was analyzed.The observations and conclusions show that correlation characteristics is closely related to distribution of the scatterers and the angle of the antenna array under the non-isotropic scattering environment and is affected by the elevation angle of the antenna array under the isotropic scattering environment.And the space-time correlation characteristics in high vehicular traffic density is significantly lower than that in low vehicular traffic density.The corresponding simulation model is also derived by using a reasonable parameter calculation method.The simulation results validate the rationality of proposed model.It greatly improves analysis and simulation efficiency of V2V MIMO system.…”
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Adaptive Super-Twisting Algorithm-Based Nonsingular Terminal Sliding Mode Guidance Law by Fang Yang, Kuanqiao Zhang, Lei Yu

“…Based on the proposed adaptive supertwisting algorithm and the sliding mode surface, a guidance law with the impact angle constraint is designed. The global finite-time convergence of the guidance law is proved by constructing the Lyapunov function. …”
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Clinical effects of modified Halo-pelvic traction in patients with severe spinal deformities and respiratory disorders by Yunfei Yang, Lijun Huang, Guofeng Zhao, Jiyuan Xia, Xinqi Tian, Chang Liu, Qingfu Xia

“…Pearson’s statistical correlation analysis was used to investigate the effect of the Cobb angle of the principal curvature on lung function indicators. …”
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基于轮齿载荷分析的斜齿轮最优螺旋角确定方法 by 唐毅, 杨军

“…A method to improve the dynamic characteristics of gear system is proposed through the selection of spiral angle of helical gear according to gear system dynamics theory.Based on the finite element theory,the laws of tooth load distribution in long direction and load distribution between tooth and the expression of gear parameters and tooth load through the comparison with the variation laws of contact wire of gear tooth in meshing process are obtained.Then,the calculation formula for optimal helix angle of helical gear regarding the variation laws of contact wire least as the target function are deduced,and the formula correctness through the comparison of the meshing stiffness of different helix angle is proved.The results provided theoretical base for the optimization of design parameter of helical gear.…”
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基于图形界面的汽车断开式转向传动机构优化设计 by 姚永玉, 吕纯洁, 周远

“…Under the conditions of the requirements of vehicle for disconnect steering system and meeting the steering performance,the objective function of tracking the desirable Ackman Angle is established.By using optimal toolbox of MATLAB,the optimization modeling and solving are carried out to seek the optimal solution of some parameters,as the length of trapezoid arm,transmission angle,install offset distance and so on.Relative to the original design value,it is accuracy to guarantee the steering angle in commonly range,lowers the car’s tire wear at a high speed for the wheels turning errors,and the GUI interface is also made,the parameters of visual input and the output of optimum results are achieved.Finally,an example is used to verify the correctness of the model.…”
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