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Densification Mechanism of Warm Compaction and Powder Mixture Designing Rules 被引量:10
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作者 CAO Shun hua,HUANG Bai yun,QU Xuan hui,YI Jian hong(State Key Laboratory for Powder Metallurgy, Central South University of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 2000年第1期4-6,共3页
By phenomenological analysis of warm compaction, it is found that, compared with the contribution of particle plastical deformation to densification of powder compact,the particle rearrangement is a dominant densifica... By phenomenological analysis of warm compaction, it is found that, compared with the contribution of particle plastical deformation to densification of powder compact,the particle rearrangement is a dominant densification mechanism for powder warm compaction, and the plastical deformation of particles plays an important role in offering accommodating deformation for particle rearrangement and densifying powder compact at the final stage of pressing.In order to attain density gain as high as possible during warm compaction, six rules for designing warm compacting powder mixtures were proposed in detail. 展开更多
关键词 warm compaction densification mechanism powder mixture designing rule
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Innovative design and motion mechanism analysis for a multi-moving state autonomous underwater vehicles 被引量:1
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作者 GAO Fu-dong HAN Yan-yan +1 位作者 WANG Hai-dong JI Gang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1133-1143,共11页
In order to achieve the functional requirements of multi-moving state, a new autonomous underwater vehicle(AUV) provided with the functions such as the submarine vectorial thrust, landing on the sea bottom, wheel driv... In order to achieve the functional requirements of multi-moving state, a new autonomous underwater vehicle(AUV) provided with the functions such as the submarine vectorial thrust, landing on the sea bottom, wheel driving on the ground and crawling on the ground was designed. Then five new theories and methods were proposed about the motion mechanism of the AUV such as vectorial thruster technology, design of a new wheel propeller, kinematics and dynamics, navigation control and the ambient flow field in complex sea conditions, which can all conquer conventional technique shortages and predict the multi-moving state performance under wave disturbance. The theoretical research can realize the results such as a vectorial transmission shaft with the characteristics of spatial deflexion and continual circumgyratetion, parameterized design of the new wheel propeller with preferable open-water performance and intensity characteristics satisfying multi-moving state requirements, motion computation and kinetic analysis of AUV's arbitrary postures under wave disturbance, a second-order sliding mode controller with double-loop structure based on dynamic boundary layer that ensures AUV's trajectory high-precision tracking performance under wave disturbance, fast and exact prediction of the ambient flow field characteristics and the interaction mechanism between AUV hull and wheel propellers. The elaborate data obtained from the theoretical research can provide an important theoretical guidance and technical support for the manufacture of experimental prototype. 展开更多
关键词 multi-moving state autonomous UNDERWATER vehicle inNOVATIVE design motion mechanism wave DISTURBANCE
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Design of Rotary Vane Pump Based on Numerical Simulation and Performance Research
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作者 REN Zheng SONG Qiao-le 《印刷与数字媒体技术研究》 北大核心 2025年第5期286-291,共6页
In the printing industry,vacuum pumps play a critical role in sheet feeding and gripping processes.In order to improve the efficiency of vacuum pumps,By analyzing the internal flow field of the vane type vacuum pump,t... In the printing industry,vacuum pumps play a critical role in sheet feeding and gripping processes.In order to improve the efficiency of vacuum pumps,By analyzing the internal flow field of the vane type vacuum pump,the CFD method was used to simulate the internal flow field of the air pump,and it was found that a main vortex was formed near the rotor of the trailing blade.Based on this observation,a new rotor shape design was proposed in this study,which design places arc-shaped depressed on the circumference of the rotor where the main vortex forms.The existence of the depression facilitated forward motion of the main airflow and thus effectively restricting reverse flow.Simulation results demonstrated that the proposed design is able to decrease pressure-induced torque load on the pump,and the reduction increases for an increasing operating speed.For all three operating speeds tested,the reduction in pressure-induced torque ranges from 5%to up to 10%comparing to the original pump. 展开更多
关键词 Rotary vane pump CFD Novel design Mechanical efficiency Vacuum pump
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α-In_(2)Se_(3)铁电沟道场效应晶体管及其突触性能
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作者 胡辰 彭松昂 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第3期103-108,共6页
利用机械剥离法制备α-In_(2)Se_(3)二维铁电材料,通过原子力显微镜分析样品的结构特征,并通过电子束光刻制备以α-In_(2)Se_(3)作为沟道的铁电沟道场效应晶体管。研究发现:通过在顶栅电极施加正负脉冲可以有效激励α-In_(2)Se_(3)面外... 利用机械剥离法制备α-In_(2)Se_(3)二维铁电材料,通过原子力显微镜分析样品的结构特征,并通过电子束光刻制备以α-In_(2)Se_(3)作为沟道的铁电沟道场效应晶体管。研究发现:通过在顶栅电极施加正负脉冲可以有效激励α-In_(2)Se_(3)面外极化,表现出增强和抑制的短程可塑性。并且,随着栅极电压脉冲积累,α-In_(2)Se_(3)面外极化特性会使得沟道铁电极化加强,对应的突触电流也会随之增加,从而实现由短程可塑性向长程可塑性的转变。此外,不同脉幅的激励信号可以调整长时程增强特性,展现了器件应用于复杂突触学习行为的可行性。 展开更多
关键词 机械剥离法 α-in_(2)Se_(3)二维铁电材料 面外极化 铁电沟道场效应晶体管 突触晶体管
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DYNAMICAL OPTIMUM DESIGN OF THE MECHANICAL OSCILLATION SYSTEM IN FLUIDIC GENERATOR
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作者 李福松 陈建军 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共4页
文中通过对射流发电机工作原理、结构特点及作用荷载的分析,建立了射流发电机机械振动系统的动力优化设计数学模型,以结构尺寸为设计变量,使结构重量极小化,满足动力位移、应力响应、基频以及尺寸限等约束条件,利用振型迭加法和复... 文中通过对射流发电机工作原理、结构特点及作用荷载的分析,建立了射流发电机机械振动系统的动力优化设计数学模型,以结构尺寸为设计变量,使结构重量极小化,满足动力位移、应力响应、基频以及尺寸限等约束条件,利用振型迭加法和复合形法求解。优化和试验结果表明:经优化后,既减轻结构重量,又显著地提高了射流发电机的输出功率。 展开更多
关键词 引信 射流技术 电源 有限元法 动力响应 动力优化 DYNAMICAL OPTIMUM design OF THE MECHANICAL
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Hybridizing artificial bee colony with biogeography-based optimization for constrained mechanical design problems 被引量:2
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作者 蔡绍洪 龙文 焦建军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2250-2259,共10页
A novel hybrid algorithm named ABC-BBO, which integrates artificial bee colony(ABC) algorithm with biogeography-based optimization(BBO) algorithm, is proposed to solve constrained mechanical design problems. ABC-BBO c... A novel hybrid algorithm named ABC-BBO, which integrates artificial bee colony(ABC) algorithm with biogeography-based optimization(BBO) algorithm, is proposed to solve constrained mechanical design problems. ABC-BBO combined the exploration of ABC algorithm with the exploitation of BBO algorithm effectively, and hence it can generate the promising candidate individuals. The proposed hybrid algorithm speeds up the convergence and improves the algorithm's performance. Several benchmark test functions and mechanical design problems are applied to verifying the effects of these improvements and it is demonstrated that the performance of this proposed ABC-BBO is superior to or at least highly competitive with other population-based optimization approaches. 展开更多
关键词 artificial bee colony biogeography-based optimization constrained optimization mechanical design problem
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Response surface methodology-based hybrid robust design optimization for complex product under mixed uncertainties 被引量:1
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作者 WAN Liangqi CHEN Hongzhuan OUYANG Linhan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期308-318,共11页
Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research top... Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research topic to enhance the robustness.However, most of the existing works in the CPCM robust design optimization neglect the mixed uncertainties, which might result in an unstable design or even an infeasible design. To solve this issue, a response surface methodology-based hybrid robust design optimization(RSM-based HRDO) approach is proposed to improve the robustness of the quality characteristic for the CPCM via considering the mixed uncertainties in the robust design optimization. A bridge-type amplification mechanism is used to manifest the effectiveness of the proposed approach. The comparison results prove that the proposed approach can not only keep its superiority in the robustness, but also provide a robust scheme for optimizing the design parameters. 展开更多
关键词 response surface METHODOLOGY (RSM) HYBRID robust design optimization (HRDO) uncertainty complex product of compliant mechanism (CPCM)
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Design methods of headed studs for composite decks of through steel bridges in high-speed railway 被引量:1
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作者 侯文崎 叶梅新 《Journal of Central South University》 SCIE EI CAS 2011年第3期946-952,共7页
Aimed at two typical composite floor systems of through steel bridges in high speed railway,design methods of headed studs were put forward for different composite members through comparing and analyzing the structure... Aimed at two typical composite floor systems of through steel bridges in high speed railway,design methods of headed studs were put forward for different composite members through comparing and analyzing the structure,mechanical characteristics and transmission routes of deck loads.The simplified calculation models were brought out for the stud design of the longitudinal girders and transverse girders in the composite floor system of Nanjing Dashengguan Yangtze River Bridge (NDB).Studs were designed and arranged by taking the middle panel of 336 m main span for example.The results show that under deck loads,the longitudinal girders in the composite floor system of through steel bridges are in tension-bending state,longitudinal shear force on the interface is caused by both longitudinal force of "The first mechanical system" and vertical bending of "The second mechanical system",and studs can be arranged with equal space in terms of the shear force in range of 0.2d (where d is the panel length) on the top ends.Transverse girders in steel longitudinal and transverse girders-concrete slab composite deck are in compound-bending state,and out-of-plane bending has to be taken into account in the stud design.In orthotropic integral steel deck-concrete slab composite deck,out-of-plane bending of transverse girders is very small so that it can be neglected,and studs on the orthotropic integral steel deck can be arranged according to the structural requirements.The above design methods and simplified calculation models have been applied in the stud design of NDB. 展开更多
关键词 through steel bridge steel-concrete composite deck mechanical characteristics STUD design method
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Study of simple plane wave generator with an air-metal barrier 被引量:2
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作者 Wei XIONG Xian-feng ZHANG +3 位作者 Zhong-wei GUAN Yong HE Liang QIAO Li-li GUO 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第2期190-197,共8页
Plane wave generators(PWGs) are used to accelerate flyer plates to high velocities with their generated plane waves,which are widely used in the test of dynamic properties of materials.The traditional PWG is composed ... Plane wave generators(PWGs) are used to accelerate flyer plates to high velocities with their generated plane waves,which are widely used in the test of dynamic properties of materials.The traditional PWG is composed of two explosives with different detonation velocities.It is difficult to implement the related fabrication processes and control the generated waves due to its complicated structures.A simple plane wave generator is presented in this paper,which is composed of two identical cylindrical high explosive(HE) charges and an air-metal barrier.A theoretical model was established based on two different paths of the propagation of detonation waves,based on which the size of air-metal barrier was calculated for a given charge.The corresponding numerical simulations were also carried out by AUTODYN-2D based on the calculated results,which were used to compare with the theoretical calculations.A detonation wave with a flatness of 0.039 μs within the range of 70-percent diameter of the main charge was obtained through the simulations. 展开更多
关键词 平面波发生器 屏障 金属 空气 数值模拟 动态性能 制造工艺 传播路径
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Optimization Design of McPherson Suspension Steering System Based on R-W Method
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作者 卞学良 马国清 王志强 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第2期144-149,共6页
The kinematical equations of McPherson suspension and steering system were set up by using R-W method of multi-rigid body system dynamics.The incidence matrix,route matrix,hinge vector matrix and system constraint equ... The kinematical equations of McPherson suspension and steering system were set up by using R-W method of multi-rigid body system dynamics.The incidence matrix,route matrix,hinge vector matrix and system constraint equations were educed.The optimization model of McPherson suspension steering mechanism was founded by regarding the McPherson suspension and steering system as an integrated system.In order to gain the best optimization effect,a continuous weighting function was created according to the requirement of steering system performance.Taking example for TJ7136U,the optimization design of McPherson suspension steering system was conducted in this paper. 展开更多
关键词 MECHANICS R-W method McPherson suspension optimization design weighting function
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Feed back Mechanism in Decision Support Systems
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作者 Sun Zhanshan(Institute of SE. Dalian Maritime University, 116024, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1997年第2期53-59,共7页
Feedback mechanism is a specific feature of control systems, however, the similarity has been found in decision support systems. Just because of this, the DSS can provide a flexible learning and thinking environment, ... Feedback mechanism is a specific feature of control systems, however, the similarity has been found in decision support systems. Just because of this, the DSS can provide a flexible learning and thinking environment, and help decision maker to solve semistructured and unstructured problems actively and creatively. In this paper, the role and type of the feedback in decision making are discussed from different point of view. This is also true in DSS because it supports decision making. The feedback design, especially the feedback interface design, is described through a case of practice DSS. Based on these points, the feedback mechanism is an important feature of DSS, and it is one of the differences between DSS and MIS. 展开更多
关键词 Feedback mechanism Decision making Decision support system Feedback interface design.
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Study on Approach for Computer-Aided Design and Machining of General Cylindrical Cam Using Relative Velocity and Inverse Kinematics
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作者 Se-Hwan Park Byong-Kook Gu +1 位作者 Joong-Ho Shin Geun-Jong Yoo 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期205-,共1页
Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa t... Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa tic transfer equipments. This paper proposes a new approach for the shape design and manufacturing of the cylindrical cam. The design approach uses the relative velocity concept and the manufacturing approach uses the inverse kinematics concept. For the shape desig n, the contact points between the cam and the follower roller are calculated bas ed on relative velocity of which the direction is on the common tangential line, and then the whole shape of cam is determined from transformation of the coordi nate system. For the manufacturing procedures, the location and the orientation of cutter path can be allocated corresponding to the designed shape data. The in tegral NC code for multi-axis CNC machining center is created using the inverse kinematics concept from the data of the location and the orientation of cutter path. As the advantages of the proposed approach, the machine tool is designed t o having an alternative size in fabricating the general cam, while the tool must be fitted to diameter size of the follower in the conventional approach. Finally, CAD/CAM program, "Cylindrical DAM", is developed on C++ lan guage. This program can perform shape design, manufacturing and kinematics simul ation, which can make integral NC code for multi-axis CNC machining center. The proposed method can be applied easily on fields of industries. 展开更多
关键词 Cylindrical Cam mechanism(CCM) shape design rel ative velocity method NC Code Multi-axis CNC machining center inverse kinema tics
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Research on and Design of Mechanical System with Optimal Cutting Movement Trajectory of Energy-Saving Stone-Sawing Machine
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作者 WANG Ji-rong 1, LI Lan-ji 1, LI Jun 1,3, LI Hua 2, ZHONG Yun-qing 3 (1.Qingdao University, Qingdao 266071, China 2.Wendeng Foreign Economic and Trade Corp, Wendeng 264400, China 3.Qingdao University of Science and Technology, Qingdao 266042, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期140-141,共2页
The technique of cutting slabstone with stone-sawi ng machine is analyzed completely. A new kind of cutting movement trajectory is gi ven whose actual cutting efficiency is near to 100%. It can reduce the energy w ear... The technique of cutting slabstone with stone-sawi ng machine is analyzed completely. A new kind of cutting movement trajectory is gi ven whose actual cutting efficiency is near to 100%. It can reduce the energy w earing greatly, and the surface quality of the product is improved to the utmost extent. The design mechanism of the optimal cutting movement trajectory system structure is analyzed incisively. At the same time, the principle of the complex movement of horizontal movement and swing is researched. The optimal design scheme of th e cutting movement trajectory system structure is set up. The choice method to g et the superior value of the movement system structure is found. The mathematics function formula is established which exhibits the relationship between the par ameter of the complex movement structure and that of the system movement structu re. By the formula, the precision value of the offset can be figured out. The r ule is adapted to different types of energy-saving stone-sawing machines. The complex movement structure of horizontal movement and swing is designed to f ulfill the cutting movement. It can make the saw frame move up with the hanging pod deviating from the vertical direction. At the same time, the saw frame have a down-movement. Then the sum of the two movements is near to zero, and the saw blade and the stone can keep in touch during the whole horizontal cutting. The result is that the actual cutting efficiency is 100%. Also, when the hanging pod moves to the limited position, the saw frame can keep the original inertia, and continue to swing up. It makes the back-cutting have high energy-storing. The optimal design of the eccentricity balance wheel is done. The mathematics fo rmula for expressing the movement system structure is deduced. The calculation m ethod and formula is set up which is used to get the value of important componen ts such as offset. The choice method and formula of elasticity distortion coeffi cient is set up when the saw frame moves smoothly. It is concluded that the offs et is the key dimension to actualize the optimal cutting movement trajectory. The resolving of the technical problems discussed above offers a theoretic and technical basis for optimal design of energy-saving stone-sawing machines. 展开更多
关键词 design Research on and design of Mechanical System with Optimal Cutting Movement Trajectory of Energy-Saving Stone-Sawing Machine
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粗粒土力学特性大型平面应变试验研究 被引量:2
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作者 姜景山 左永振 +3 位作者 程展林 黄鑫 张超 王志华 《长江科学院院报》 北大核心 2025年第1期129-135,143,共8页
土石坝填料一般处于平面应变状态,目前填料力学特性研究基本采用大型三轴试验。由于三轴应力状态下中主应力等于小主应力,平面应变状态下大坝填料的力学性能会被低估。为充分认识填料潜能,科学设计和合理评估土石坝,有必要对填料开展平... 土石坝填料一般处于平面应变状态,目前填料力学特性研究基本采用大型三轴试验。由于三轴应力状态下中主应力等于小主应力,平面应变状态下大坝填料的力学性能会被低估。为充分认识填料潜能,科学设计和合理评估土石坝,有必要对填料开展平面应变试验研究。应用大型真三轴仪对填料进行了大型平面应变试验,共开展了4种不同初始干密度的粗粒土平面应变各向等压固结排水剪切试验。结果表明:应力-应变关系主要为应变硬化型,应力曲线呈爬升型,体变表现为剪缩。某一小主应力下,大小主应力之差的最大值随初始干密度的增大呈线性增大;初始干密度一定时,大小主应力之差的最大值与小主应力呈线性关系增大。初始剪切阶段,小主应力一定时,偏应力与球应力之比曲线斜率随初始干密度的增大而增大,随剪切变形的发展,不同初始干密度的应力比曲线逐渐趋于接近。偏应力随球应力的增大单调增加则对应应变硬化型,若偏应力随球应力的增大先增加后减小则对应应变软化型。相同小主应力时,初始弹性模量随初始干密度的增大而增大,近似呈线性关系;某一初始干密度下,初始弹性模量随小主应力的增大基本呈线性关系增大。中主应力系数随大主应力方向应变的增大而增大,曲线形态呈三折线形,初始剪切阶段增长较为缓慢,随剪切变形的增大增长相对加快并呈线性关系增大,如曲线末端下弯为应变硬化型,曲线末端上翘为应变软化型。 展开更多
关键词 粗粒土 大型平面应变试验 力学特性 主应力 偏应力 球应力 大型真三轴仪
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对称式蔬菜单株自动嫁接机设计与试验 被引量:2
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作者 王家胜 李洋鹏 +1 位作者 高春风 王东伟 《农业机械学报》 北大核心 2025年第1期141-150,共10页
根据茄科蔬菜贴接法嫁接工艺要求,设计了一种对称式蔬菜单株自动嫁接机,在PLC系统控制下,可以连续自动完成对砧穗木苗株的夹取传送、切削、对接以及对嫁接夹裁切、持夹上夹、夹苗固定等功能。重点设计了构成嫁接机的取送苗机械臂、夹持... 根据茄科蔬菜贴接法嫁接工艺要求,设计了一种对称式蔬菜单株自动嫁接机,在PLC系统控制下,可以连续自动完成对砧穗木苗株的夹取传送、切削、对接以及对嫁接夹裁切、持夹上夹、夹苗固定等功能。重点设计了构成嫁接机的取送苗机械臂、夹持苗机械手、砧穗木切削装置、裁夹上夹装置以及控制系统,确定了各机构关键结构参数以及控制流程。选择辣椒苗为嫁接对象,开展了蔬菜单株自动嫁接机样机性能试验,试验结果表明,各环节执行时间越短,即加快执行速度,嫁接合格率均会下降,影响程度由大到小依次为对接苗时间、上夹时间和取送切苗时间。嫁接苗损伤率的影响则集中在取送切苗环节,该环节执行速度越快,嫁接苗损伤率会有所上升。在各环节执行时间优化基础上,分别对主夹指高度和砧穗木切削装置刀刃倾角进行单因素结构优化试验,获得最优主夹指高度和刀刃倾角分别为13 mm和25°。优化后蔬菜单株自动嫁接机嫁接效率为300株/h,损伤率为2.5%,嫁接合格率为94.8%,达到了设计要求。 展开更多
关键词 嫁接机 茄科蔬菜 机构设计 自动取苗 嫁接夹裁切
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基于图神经网络铁路桥梁主梁推荐算法研究 被引量:1
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作者 柏华军 郑洪 +1 位作者 陈瓴 桂浩 《铁道标准设计》 北大核心 2025年第8期72-79,共8页
随着智能技术的发展,铁路桥跨方案布孔设计一直朝着一体化、数字化、可视化、智能化的方向发展。国内外针对铁路桥梁智能设计的研究主要集中在铁路桥梁模型构造与协同设计方向,关于桥梁智能布孔设计还属于技术空白。在此背景下,研发基... 随着智能技术的发展,铁路桥跨方案布孔设计一直朝着一体化、数字化、可视化、智能化的方向发展。国内外针对铁路桥梁智能设计的研究主要集中在铁路桥梁模型构造与协同设计方向,关于桥梁智能布孔设计还属于技术空白。在此背景下,研发基于图神经网络AGOAM模型的铁路桥梁主梁推荐算法,实现桥跨范围控制点的主梁选型,为桥跨方案智能决策算法提供支撑。深入研究前沿智能推荐技术,提出由预处理层、子图构建层、节点匹配层、图池化层和图匹配层组成的AGOAM模型,基于控制点-梁型的内外部属性交互技术和融合注意力机制的本体特征加强技术,实现控制点和梁型图谱嵌入表示优化和基于相识度算法控制点与梁型高效匹配。模型在验证集AUC、LogLoss、Precision、NDCG指标表明,算法准确度、排序能力和推荐质量效果良好。 展开更多
关键词 铁路桥梁 布孔设计 图神经网络 智能设计 注意力机制 推荐算法 相识度算法
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航空光电大口径平面光学窗口厚度尺寸设计分析
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作者 程刚 王惠林 +4 位作者 张博 王涛 卢恒 曹尹琦 周帆 《应用光学》 北大核心 2025年第3期580-588,共9页
航空光电装备平面光学窗口在确定构型尺寸和组合形式后,窗口厚度对装备成像性能影响至为关键。从设计变量、组合形式、作用载荷3个方面对窗口设计问题进行分析,确定了基于结构刚性和RMS(root mean square)波前误差的平面窗口厚度设计目... 航空光电装备平面光学窗口在确定构型尺寸和组合形式后,窗口厚度对装备成像性能影响至为关键。从设计变量、组合形式、作用载荷3个方面对窗口设计问题进行分析,确定了基于结构刚性和RMS(root mean square)波前误差的平面窗口厚度设计目标;从光学窗口一阶结构谐振频率及其在温度和压力载荷作用下的RMS波前误差量化求解出窗口厚度尺寸范围11.9 mm~18.4 mm;提出针对光学窗口组合工况性能计算的集成分析流程,计算得到光学窗口一阶谐振频率为151 Hz,在飞行工作时各向组合工况-流场/重力/振动作用下光学窗口RMS波前误差不大于1/10参考波长。实验测试结果表明:光学窗口RMS波前误差小于0.07参考波长,实物样机振动和飞行条件下成像清晰、稳定,证明窗口厚度尺寸设计分析方法正确有效。 展开更多
关键词 平面光学窗口 厚度尺寸 设计分析 组合工况
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生物大模型技术前沿与应用进展 被引量:1
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作者 石金龙 张哲 +2 位作者 戴安琳 林恺 何昆仑 《生理科学进展》 北大核心 2025年第3期235-242,共8页
以基因、转录、蛋白质等生命组学为主体的生物大数据快速积累和以深度学习为代表的人工智能技术迅猛发展,催生出各种类别的生物大模型(biological large models)。复杂的深度学习架构、巨大的参数量和算力需求、以及海量的预训练数据等... 以基因、转录、蛋白质等生命组学为主体的生物大数据快速积累和以深度学习为代表的人工智能技术迅猛发展,催生出各种类别的生物大模型(biological large models)。复杂的深度学习架构、巨大的参数量和算力需求、以及海量的预训练数据等是大模型技术的主要特征。预训练数据类别及参数量一定程度上决定了大模型所具备的能力强弱,而不同的模型架构则可支撑不同类别的下游任务。近两年,围绕DNA/RNA/蛋白质等生物序列与单细胞表达图谱等组学数据分析挖掘、大分子结构预测、新型药物设计和功能机制解析等多种应用场景,涌现了多种通用或专用大模型,展示出其在生物医学研究及转化应用等领域的巨大潜力。本文旨在结合不同类别的生物数据特点和研究应用需求,概述生物数据特征及其用于生物大模型训练的技术方法,并进一步综述现有大模型在生物医学研究及疾病诊疗中的应用进展,为提升生物大模型能力、拓展应用范围提供新的思路。 展开更多
关键词 生物大模型 注意力机制 序列分析 结构预测 功能解读 合成设计
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面向新工科和工程教育专业认证的《机械设计》课程建设探索 被引量:1
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作者 刘世豪 马庆芬 +1 位作者 罗洪峰 林茂 《机械设计》 北大核心 2025年第9期196-202,共7页
为贯彻“新工科”和工程教育专业认证的核心理念,对海南大学机械设计制造及其自动化专业的机械设计课程教学与考核现状进行了深入分析。在此基础上总结了当前课程建设中存在的一系列问题,并提出了相应的课程建设方法,主要集中在以下几... 为贯彻“新工科”和工程教育专业认证的核心理念,对海南大学机械设计制造及其自动化专业的机械设计课程教学与考核现状进行了深入分析。在此基础上总结了当前课程建设中存在的一系列问题,并提出了相应的课程建设方法,主要集中在以下几个方面:课程教学内容、教学方式、实验教学和考核方式等。基于2019级机械设计制造及其自动化专业机械设计课程考核的实际案例,进行达成度分析,验证了课程建设所带来的积极影响,为学生的学习与工程创新能力的培养奠定了良好基础。 展开更多
关键词 新工科 工程教育专业认证 机械设计 课程建设 工程创新能力
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项目驱动下机械创新设计课程思专创融合教学模式构建与实践 被引量:1
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作者 杨淑华 袁大超 +3 位作者 孔德刚 郝建军 李文良 张秀花 《农机使用与维修》 2025年第1期117-124,共8页
针对新工科教育下国家对综合性、复杂型工程科技人才的培养需求,基于成果导向教育(OBE)与工程认证教育理念,结合机械创新设计课程特点,河北农业大学机电工程学院积极探索和实践项目驱动式的专创融合教学模式。以专业理论为主线,以立德... 针对新工科教育下国家对综合性、复杂型工程科技人才的培养需求,基于成果导向教育(OBE)与工程认证教育理念,结合机械创新设计课程特点,河北农业大学机电工程学院积极探索和实践项目驱动式的专创融合教学模式。以专业理论为主线,以立德树人为核心目标,通过科研项目与双创作品项目驱动,将创新创业思维工具融入课程教学,引导学生自主探究学习和创新设计实践,构建了“四线并驱,两赛促学”的思专创融合教学新范式,为专业课程专创融合的实施提供了有益的借鉴和参考。 展开更多
关键词 项目驱动式 机械创新设计 思专创融合
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