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Analysis and Design of Cylindrical Magnetorheological Fluid Brake 被引量:3
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作者 HUANG Jin, ZHANG Jun-qian, YANG Yan (Department of Engineering Mechanics, Chongqing University, Chongqing 400044, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期27-28,共2页
Magnetorheological (MR) fluids consist of stable suspensions of magnetic particles in a carrying fluid such as water or silicone oils. The magnetorheological response of MR fluids results from the polarization induced... Magnetorheological (MR) fluids consist of stable suspensions of magnetic particles in a carrying fluid such as water or silicone oils. The magnetorheological response of MR fluids results from the polarization induced in suspended particles by application of an external magnetic field. The interaction between the induced dipoles causes the particles to form columnar structure, parallel to the applied field. These chain-like structures restrict the motion of fluids, thereby increasing the viscosity and yield stress of the MR fluids. These mechanical characteristics allow for the construction of magnetically controlled device such as the MR fluids rotary brakes. However, there has been little information published about the design of MR fluid brakes. In this paper the design of the cylindrical MR fluid brake is investigated theoretically. Bingham model is used to characterize the constitutive behaviors of the MR fluids subject to an external magnetic field. The operational principle of the cylindrical MR fluid brake is presented. The theoretical method is developed to analyze the transmission properties of the torque of the cylindrical MR fluid brake. An engineering expression for the torque is derived to provide the theoretical foundations in the design of the cylindrical MR fluid brake. Based on this equation the volume and thickness of the annular MR fluids within the brake is expressed as functions of the desired ratio of torques with saturated magnetic field and without external field, the controlled mechanical power and the MR fluid material properties. The parameters of the thickness and width of the fluid in the brake can be calculated from the obtained equations when the required mechanical power level, the desired torque ratio are specified. 展开更多
关键词 MR fluids BRAKE analysis method design method
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The Computer Aided Integrated Design and Analysis of Oil Tank in Vehicle 被引量:1
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作者 CHEN Xu 1, CHEN Yong-guang 2 (1. Mechanical Engineering Institute, Chongqing University, Chongqing 400044, China 2. Logistical Engineering University, Chongqing 400016, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期269-,共1页
This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oi... This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oil tank is greatly improved. Adopting integrated CAD/CAE/CAM software to carry out integrated research to equ ipment and products, we will be able to take overall analysis in aspects of 3-D solid modeling, pre-assembly and strength, etc., to realize non-paper designi ng and parallel designing. Problems can be found and settled during designing, w hich will increase designing efficiency and one-time success rate and realize o ptimum designing for products. 展开更多
关键词 oil tank solid modeling finite element analysis integrated design
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3D Design and Analysis of Crushing Roller of High-pressure Grinding Roller 被引量:1
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作者 GAO Hang 1, QU Li-gang 2 (1. School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110004, China 2. Department of Mechanical Engineering, Shenyang Institute of Aeronautical Engineering, Shenyang 110034, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期158-,共1页
Crushing roller is one of the main parts of High-p re ssure Grinding Roller, which is a kind of high efficient ore crushing equipment. A kind of assembled roller, which is more convenient to renovate worn surface b y ... Crushing roller is one of the main parts of High-p re ssure Grinding Roller, which is a kind of high efficient ore crushing equipment. A kind of assembled roller, which is more convenient to renovate worn surface b y simply replacing segmented surface of the roller, was developed. The structura l models of assembled roller’s components were designed with SolidWorks softwar e based on feature modeling, these solid models of the roller were virtually ass embled. Through this work, not only was the assemble interference checked out so as to examine validity of the structure design, but also these solid models cou ld be recognized by COSMOS/Works software, through which the finite element an alysis can be done. Then the stress and displacement of the main shaft and sur face segment in two different working states were analyzed and detected quickly according to the analysis results with COSMOS/Works. In conclusion, the optimum clearance of 1.0~2.0 mm between concave-convex studded segments is determined to make the using life of assembled roller longer. 展开更多
关键词 high-pressure grinding roller 3D design assemb led roller finite element analysis
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Structural design and modal behaviors analysis of a new swept baffled inflatable wing 被引量:1
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作者 Nuo Ma Li Liu +1 位作者 Fanmin Meng Junhui Meng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期382-398,共17页
Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of... Inflatable wing has significant application value in the design of loitering munitions because of its advantages such as lightweight and foldability.However,due to the flexible characteristics,aeroelastic behaviors of inflatable wings such as flutter are nonnegligible in flight.By designing a certain angle between the inflatable beam and the wing span,the structural dynamic and even the aeroelastic performance of the inflatable wing can be effectively improved.Based on the analysis of the mechanical and geometric characteristics of the inflatable structure,a new inflatable wing with sweep arranged inflatable beams is proposed,and the main design variables and methods are analyzed.For purpose of investigating the aeroelastic performance of the swept baffled inflatable wing,the modal behaviors by considering the wet mode are studied.In consideration of the deficiencies of the traditional wet modal analysis method,by introducing the influence on the additional stiffness of flow field,an added massstiffness method is proposed in this paper,and the advantages are verified by ground vibration experiments.On this basis,the effects of baffles sweep angle,pressure,and boundary conditions on the modal parameters and aeroelastic performance of inflatable wing are analyzed.The results show that the aeroelastic performance of the inflatable wing can be designed by changing the baffles sweep angle,which is enlightened for the aeroelastic tailoring design on inflatable wings. 展开更多
关键词 Inflatable wing Structural design Wet mode Flutter analysis
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Analysis and design of resistance-wire heater in MOCVD reactor 被引量:1
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作者 曲毓萱 王斌 +5 位作者 胡仕刚 吴笑峰 李志明 唐志军 李劲 胡莹璐 《Journal of Central South University》 SCIE EI CAS 2014年第9期3518-3524,共7页
Metal organic chemical vapor deposition(MOCVD) is a key equipment in the manufacturing of semiconductor optoelectronic devices and microwave devices in industry. Heating system is a vital part of MOCVD. Specific heati... Metal organic chemical vapor deposition(MOCVD) is a key equipment in the manufacturing of semiconductor optoelectronic devices and microwave devices in industry. Heating system is a vital part of MOCVD. Specific heating device and thermal control technology are needed for each new reactor design. By using resistance-wire heating MOCVD reaction chamber model, thermal analysis and structure optimization of the reactor were developed from the vertical position and the distance between coils of the resistance-wire heater. It is indicated that, within a certain range, the average temperature of the graphite susceptor varies linearly with the vertical distance of heater to susceptor, and with the changed distances between the coils; furthermore, single resistance-wire heater should be placed loosely in the internal and tightly in the external. The modulate accuracy of the temperature field approximately equals the change of the average temperature corresponding to the change of the coil position. 展开更多
关键词 metal organic chemical vapor deposition (MOCVD) reactor design thermal analysis filament heating
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A Framework for Web-Based Mechanical Design and Analysis
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作者 Chiaming Yen Wujeng Li 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期210-,共1页
In this paper, a Web-based Mechanical Design and A na lysis Framework (WMDAF) is proposed. This WMADF allows designers to develop web -based computer aided programs in a systematic way during the collaborative mec han... In this paper, a Web-based Mechanical Design and A na lysis Framework (WMDAF) is proposed. This WMADF allows designers to develop web -based computer aided programs in a systematic way during the collaborative mec hanical system design and analysis process. This system is based on an emerg ing web-based Content Management System (CMS) called eXtended Object Oriented P ortal System (XOOPS). Due to the Open Source Status of the XOOPS CMS, programs d eveloped with this framework can be further customized to satisfy the demands of the user. To introduce the use of this framework, this paper exams three differ ent types of mechanical design and analysis problems. First, a repetitive design consideration and calculation process is transferred into WMADF programs to gai n efficiency for wired collaborative team. Second, the considered product solid model is created directly through the use of XOOPS program and Microsoft Compone nt Object Model (COM) instances. To the end of the paper, an example linked with ANSYS is used to indicate the possible application of this framework. 展开更多
关键词 WEB-BASED mechanical design and analysis frame work CMS XOOPS COM ANSYS
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Methanol Distillation System: Process Analysis and Column Design
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作者 Sun Jinsheng Tian Yufeng Xu Shimin Ding Hui Wang Tao Li Xingang Zheng Yanmei 《化工进展》 EI CAS CSCD 北大核心 2005年第z1期40-51,共12页
Base on industrial research and experience, the process of methanol distillation is analyzed,and above all, a new concept of high pressure flowsheet and low pressure flowsheet is defined. The new configuration helps t... Base on industrial research and experience, the process of methanol distillation is analyzed,and above all, a new concept of high pressure flowsheet and low pressure flowsheet is defined. The new configuration helps to handle problems encountered in many factories in China. The inter influence between process and column internal pattern is also pointed out. Recommendation of new column internal designs is given. Finally, industrial examples tell the how the new concept works and the possibility of combining process to give more opens to solve engineering problems. 展开更多
关键词 METHANOL distillation two - effect distillation high PRESSURE flowsheet and low PRESSURE flowsheet flowsheet analysis simulation with hydraulic COLUMN INTERNAL design
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Object-Oriented Design for FDTD Visual Scientific Computing
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作者 Dong, X. Wang, W. Wang, G. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第3期71-75,共5页
A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and sep... A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and separating from the iteration procedure, the visual software can be adapted to more comprehensive computing problems. Real-time gray degree graphic and wave curve of the results can be achieved using DirectX technique. The special difference equation and data structure in dispersive medium are considered, and the peculiarity of parameters in perfectly matched layer are also discussed. 展开更多
关键词 Computational methods Computer aided design Data structures Difference equations Finite difference method Iterative methods Natural sciences computing Object oriented programming Parameter estimation Three dimensional computer graphics Time domain analysis
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Design method of high prestressed support for shallow-buried large-span caverns
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作者 JIANG Bei WEI Hua-yong +3 位作者 WANG Qi WANG Ming-zi YIN Chen ZHANG Yan-bo 《Journal of Central South University》 2025年第3期1099-1116,共18页
The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt suppo... The surrounding rock is prone to large-scale loosening and failure after the excavation of shallow large-span caverns because of the thin overlying strata and large cross-section span.The rational design of bolt support is very important to the safety control of surrounding rock as a common support means.The control mechanism and design method of bolt support for shallow-buried large-span caverns is carried out.The calculation method of bolt prestress and length based on arched failure and collapsed failure mode is established.The influence mechanism of different influencing factors on the bolt prestress and length is clarified.At the same time,the constant resistance energy-absorbing bolt with high strength and high toughness is developed,and the comparative test of mechanical properties is carried out.On this basis,the design method of high prestressed bolt support for shallow-buried large-span caverns is put forward,and the field test is carried out in Qingdao metro station in China.The monitoring results show that the maximum roof settlement is 6.8 mm after the new design method is adopted,and the effective control of the shallow-buried large-span caverns is realized.The research results can provide theoretical and technical support for the safety control of shallow-buried large-span caverns. 展开更多
关键词 Hoek-Brown strength criterion shallow-buried large-span caverns limit analysis upper bound method high prestress bolt support design method
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Predicting configuration performance of modular product family using principal component analysis and support vector machine 被引量:1
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作者 张萌 李国喜 +1 位作者 龚京忠 吴宝中 《Journal of Central South University》 SCIE EI CAS 2014年第7期2701-2711,共11页
A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a n... A novel configuration performance prediction approach with combination of principal component analysis(PCA) and support vector machine(SVM) was proposed.This method can estimate the performance parameter values of a newly configured product through soft computing technique instead of practical test experiments,which helps to evaluate whether or not the product variant can satisfy the customers' individual requirements.The PCA technique was used to reduce and orthogonalize the module parameters that affect the product performance.Then,these extracted features were used as new input variables in SVM model to mine knowledge from the limited existing product data.The performance values of a newly configured product can be predicted by means of the trained SVM models.This PCA-SVM method can ensure that the performance prediction is executed rapidly and accurately,even under the small sample conditions.The applicability of the proposed method was verified on a family of plate electrostatic precipitators. 展开更多
关键词 design configuration performance prediction MODULARITY principal component analysis support vector machine
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Automotive Interior Noise Reduction in High Frequency Using Statistical Energy Analysis
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作者 陈鑫 王登峰 +1 位作者 朱磊 马正东 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第3期161-167,共7页
Statistical energy analysis (SEA) is an effective method for predicting high frequency vibro-acoustic performance of automobiles. A full vehicle SEA model is presented for interior noise reduction. It is composed of a... Statistical energy analysis (SEA) is an effective method for predicting high frequency vibro-acoustic performance of automobiles. A full vehicle SEA model is presented for interior noise reduction. It is composed of a number of subsystems based on a 3D model with all parameters for each subsystem. The excitation inputs are measured through road tests in different conditions,including inputs from the engine vibration and the sound pressure of the engine bay. The accuracy in high frequency of SEA model is validated,by comparing the analysis results with the testing pressure level data at driver's right ear. Noise contribution and sensitivity of key subsystems are analyzed. Finally,the effectiveness of noise reduction is verified. Based on the SEA model,an approach combining test and simulation is proposed for the noise vibration and harshness (NVH) design in vehicle development. It contains building the SEA model,testing for subsystem parameter identification,validating the simulation model,identifying subsystem power inputs,analyzing the design sensitivity. An example is given to demonstrate the interior noise reduction in high frequency. 展开更多
关键词 统计能量分析 汽车内饰 高频振动 降噪 车辆模型 噪声降低 模型验证 试验压力
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Static Stiffness Analysis of a New Type 6-DOF Micro-manipulation Robot
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作者 叶鑫 张之敬 +2 位作者 姚灿 杨波 李媛 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第2期145-150,共6页
A 6-DOF micro-manipulation robot based on a 3-PPTTRS mechanism is proposed in this paper.Its static stiffness is an important index to evaluate load capacity and positioning accuracy.However,it is insufficient to cons... A 6-DOF micro-manipulation robot based on a 3-PPTTRS mechanism is proposed in this paper.Its static stiffness is an important index to evaluate load capacity and positioning accuracy.However,it is insufficient to consider the static stiffness only when the robot is in its initial pose.The stiffness in different positions and poses in its work space must be analyzed also.Thus a method to analyze the relationship between static stiffness and poses in the whole work space is presented.A static stiffness model is proposed first,and the relationship between structural parameters and static stiffness in different poses is discussed.The static stiffness analysis provides foundation for structural parameter design. 展开更多
关键词 机械设计 操纵性能 刚度分析 位置
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生成式人工智能赋能教学设计分析:需求、方法和发展 被引量:15
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作者 穆肃 陈孝然 周德青 《开放教育研究》 北大核心 2025年第1期61-72,共12页
教学目标、教学方法、教学内容、教学环境与资源、教学评价等教学设计环节的决策质量直接影响教学活动效果。当前教学设计“人类制品”与“人工制品”普遍存在设计过程和结构程序化、偏离教师设计初衷和学生个性学习需求、数字技术运用... 教学目标、教学方法、教学内容、教学环境与资源、教学评价等教学设计环节的决策质量直接影响教学活动效果。当前教学设计“人类制品”与“人工制品”普遍存在设计过程和结构程序化、偏离教师设计初衷和学生个性学习需求、数字技术运用不足与适切性不高、忽视情感投入与师生交互不足等问题。本研究在分析现实需求的基础上,借鉴四要素教学设计模型提出“学为中心:助力素养与思维培育”的理念指向和“生成式人工智能促进分析持续生成”的技术指向;构建了包含分析任务分解与规划、内容存储与记忆、功能实现与拓展、决策准确与可信四个环节的教学设计智能分析实践框架,并提供了相应实例;最后基于发展战略分析理性认识生成式人工智能赋能教学设计分析的应用挑战,展望主客观并重贯通的“师—机”协同教学设计智能分析的发展机会。 展开更多
关键词 生成式人工智能 教学设计 教学设计分析 可行方法 风险挑战
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基于可视化分析的中国传统文化产品设计研究热点与趋势 被引量:2
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作者 韩超艳 孙硕 魏永侠 《包装工程》 北大核心 2025年第2期336-344,共9页
目的 更好地促进优秀传统文化的传承与创造性转化,对基于传统文化的产品设计研究现状及热点进行可视化分析,预测未来发展趋势。方法 以中国知网(CNKI)期刊数据库作为数据来源,使用知识计量软件Cite Space对2006—2023年以“传统文化”... 目的 更好地促进优秀传统文化的传承与创造性转化,对基于传统文化的产品设计研究现状及热点进行可视化分析,预测未来发展趋势。方法 以中国知网(CNKI)期刊数据库作为数据来源,使用知识计量软件Cite Space对2006—2023年以“传统文化”和“产品设计”为主题的文献展开分析,通过年度发文量、学科期刊、作者、机构和关键词知识图谱,梳理研究热点和发展脉络。结果 运用关键词聚类分析法,得到13个聚类5个研究热点主题,即文化产品设计、博物馆文创、数字化设计、非遗传承和乡村振兴。结论 早期探索阶段侧重于构建基于中国传统文化的产品设计理论框架;中期发展阶段探索显在传统文化元素设计因子的提取与创造性转化方法;近期繁荣阶段挖掘用户潜在文化需求和审美意象,注重传统文化的创新设计和互动体验。未来研究将突破文化元素和设计符号的思维范式,致力于多学科多领域交叉融合,从文化价值转译、数字技术应用、文化内容体验等方面构建基于传统文化的产品设计研究新格局。 展开更多
关键词 产品设计 传统文化 Cite Space 可视化分析
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基于Cast Designer的壳体铸件铸造工艺设计及智能优化
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作者 巩红涛 张怀章 +3 位作者 杨磊 杨国超 马永健 李丰 《热加工工艺》 北大核心 2024年第5期103-105,共3页
使用Cast Designer铸造仿真分析软件,通过可铸性评估系统DFM,完成浇冒系统的辅助设计,然后使用DOE技术和基于遗传算法GA的智能优化技术,评估不同工艺设计方案与铸造过程参数对壳体铸件质量的影响,分析在不同的冒口、冷铁和浇注温度条件... 使用Cast Designer铸造仿真分析软件,通过可铸性评估系统DFM,完成浇冒系统的辅助设计,然后使用DOE技术和基于遗传算法GA的智能优化技术,评估不同工艺设计方案与铸造过程参数对壳体铸件质量的影响,分析在不同的冒口、冷铁和浇注温度条件下得料率和缩孔量的关系。根据对DOE模拟结果的分析,发现顶冒口和侧冒口尺寸是影响得料率和缩孔量的关键因数,再利用遗传算法GA选择最佳设计方案和参数。通过帕累托曲线得到了生产壳体铸件的最优工艺方案。 展开更多
关键词 Cast designer 缩孔 质量控制 仿真分析
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基于变异特征的10 min~72 h综合暴雨公式研究 被引量:1
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作者 王东升 李伯根 +2 位作者 杨洋 李青 李宝芬 《水文》 北大核心 2025年第2期29-36,共8页
为满足变化环境下工程设计对更长历时、更高重现期极端暴雨设计需求,以云南省不同典型区域长系列短历时年最大降水量为资料,分析了设计暴雨时程分布变异特征,提出了四参数、两变量指数函数形式综合暴雨概化公式,明确了参数推求方法,并... 为满足变化环境下工程设计对更长历时、更高重现期极端暴雨设计需求,以云南省不同典型区域长系列短历时年最大降水量为资料,分析了设计暴雨时程分布变异特征,提出了四参数、两变量指数函数形式综合暴雨概化公式,明确了参数推求方法,并进行了精度评定。结果表明:(1)提出的指数函数综合暴雨概化公式可简化暴雨公式推求过程,满足时长10 min~72 h、重现期2~100 a一遇设计暴雨计算需要,模拟精度整体优于现行暴雨公式,考虑暴雨变异特征进一步提升了公式精度。(2)建立了云南省8个典型区域10 min~72 h分段综合暴雨公式,绝对均方根误差在0.012~0.028 mm/min,相对均方根误差在2.7%~4.4%,合格率100%。 展开更多
关键词 暴雨变异分析 暴雨公式 参数确定方法 设计暴雨 云南省
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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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高速铁路箱式路基新型结构研究 被引量:1
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作者 肖宏 陈盈盈 +2 位作者 宋绪国 郭帅杰 魏绍磊 《中南大学学报(自然科学版)》 北大核心 2025年第2期781-793,共13页
主要阐述箱式路基的结构特点、荷载分类及组合,并建立车辆-轨道-箱式路基-复合地基空间力学模型对其工作特性和荷载传递开展系统研究。研究结果表明:箱式路基纵向长度应≤17.24m,底部设计厚度应≥500mm;在温度作用下无明显伸缩位移,但... 主要阐述箱式路基的结构特点、荷载分类及组合,并建立车辆-轨道-箱式路基-复合地基空间力学模型对其工作特性和荷载传递开展系统研究。研究结果表明:箱式路基纵向长度应≤17.24m,底部设计厚度应≥500mm;在温度作用下无明显伸缩位移,但在结构端缝处存在钢轨应力峰;结构不存在共振风险;在350km/h速度下,箱式路基动应力、动位移均远比限值要求小;但顶板加速度会达到3.325m/s^(2),比我国传统简支梁桥振动加速度大,但比规范限值小;与传统土质路基对比,箱式路基对动荷载的吸收和耗散更具有优势,到路基垫层时,振动衰减超过90%,因此,对箱式路基底部复合地基进行设计时可不考虑列车动荷载的影响。 展开更多
关键词 高速铁路 新型结构 箱式路基 结构设计 有限元分析 荷载传递
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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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基于动力学的轻质棒料凸溜槽曲线评估及优化
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作者 张瑞 任明阳 +3 位作者 张鹏飞 冯伟华 李浩亮 宋晓辉 《包装工程》 北大核心 2025年第15期200-211,共12页
目的凸曲线溜槽装置常用于轻质棒料的姿态变换,针对现有轻质棒料溜槽曲线设计缺乏理论指导,且曲线优劣无法量化评估,导致卡堵和物料损伤等问题,通过动力学分析和数值仿真,提出一种针对凸曲线溜槽的量化评估及优化方法,为凸曲线溜槽的设... 目的凸曲线溜槽装置常用于轻质棒料的姿态变换,针对现有轻质棒料溜槽曲线设计缺乏理论指导,且曲线优劣无法量化评估,导致卡堵和物料损伤等问题,通过动力学分析和数值仿真,提出一种针对凸曲线溜槽的量化评估及优化方法,为凸曲线溜槽的设计和优化提供参考。方法以烟支这一典型轻质棒料为研究对象,基于ADAMS仿真软件建立物料与溜槽装置的动力学模型,对影响上述现象的关键因素进行分析。通过动力学分析物料在凸曲线溜槽上的运动行为,并基于关键影响因素提出评估及优化方法。结果通过优化溜槽曲线,有效解决了物料在接触竖直挡板前飞离溜槽的问题,使得物料离开溜槽的倾斜角由64.70°提高至70.20°,评估指标理论计算值由0.97提高至1.45,评估结果与仿真及实验结果接近。结论提出了一种针对凸曲线溜槽的量化评估及优化方法,基于该优化方法得到的优化曲线相对于原曲线,降低了物料损伤程度及卡堵风险。同时,仿真及实物测试验证了所提出评估方法的有效性,适用于实际场景。 展开更多
关键词 动力学分析 性能评估 ADAMS仿真 溜槽设计
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