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Automatic generation of assembly dimension chain based on tolerance cell 被引量:2
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作者 Zhu Xinglei Li lqngguang +1 位作者 Wang Wei Liu Hao 《Computer Aided Drafting,Design and Manufacturing》 2012年第1期77-83,共7页
In the process of generating assembly dimension chain automatically, there are many problems such as complex assembly relationship, variety of constraints of components and complex dimension and tolerance relations of... In the process of generating assembly dimension chain automatically, there are many problems such as complex assembly relationship, variety of constraints of components and complex dimension and tolerance relations of components. These problems lead to many difficulties in search process and need lots of man-machine interaction. Because of these difficulties, this paper presents a method of automatic generation of assembly dimension chain based on tolerance cell. This method is realized through obtaining assembly tolerance cell and part tolerance cell first. These two types of tolerance cell are extracted and expressed in the form of linked list structure in computer further. Then assembly dimension chain is searched automatically based on obtained tolerance cell, and the correct assembly dimension chain is extracted finally. A system of generating assembly dimension chain automatically has been developed based on DELMIA and successfully deployed in aircraft assembly simulation in the engineerine practice. 展开更多
关键词 tolerance cell assembly information model assembly dimension chain
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One-dimensional Chain Dibenzo-18-crown-6 Complex: [K(DB18-C-6)]_2[Pt(SCN)_6]·2H_2O·C_2H_4Cl_2 Assembled by Cation-π Interactions 被引量:1
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作者 ZHUYue-hua DUMao-xi +2 位作者 LIDa-cheng WANGDa-qi DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期123-126,共4页
关键词 One-dimensional chain Crown ether complex Cation-π interactions Synthesis and crystal structure
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A New One-dimensional Chain Compound Constructed by {Mo_8O_(28)} units via Corner-sharing 被引量:1
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作者 YUYa-Qin YANGWen-Bin WUChuan-De LUCan-Zhong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第2期214-218,共5页
The title compound, {(H3O)4(NH4)4[Mo8O28]?2H2O}n 1, has been synthesized from the reaction of Zn(OAc)2 and (NH4)6Mo7O24?4H2O in aqueous solution at ambient tempe- rature, and its crystal structure was determined by ... The title compound, {(H3O)4(NH4)4[Mo8O28]?2H2O}n 1, has been synthesized from the reaction of Zn(OAc)2 and (NH4)6Mo7O24?4H2O in aqueous solution at ambient tempe- rature, and its crystal structure was determined by X-ray single-crystal analysis with the following crystallographic data: monoclinic system, space group P21/n, a = 9.5234(6), b = 11.3235(8), c = 14.8812(10) ?, β = 107.467(2)o, V = 1530.77(18) ?3, Z = 4, F(000) = 1336, μ = 3.293 mm-1 and Dc = 3.037 g/cm3. The final R = 0.0619 for 2691 observed reflections (I > 2σ(I)). X-ray crys- tal structure analysis showed that the novel one-dimensional chain compound is built up by basic {Mo8O28} units via single μ2-O, and such chains are further linked into a three-dimensional net- work by hydrogen bonds. 展开更多
关键词 polyoxomolybdate octamolybdate one-dimensional chain
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A MICROPAYMENT SCHEME BASED ON WEIGHTED MULTI-DIMENSIONAL HASH CHAIN 被引量:2
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作者 Liu Yining Hu Lei Liu Heguo 《Journal of Electronics(China)》 2006年第5期791-794,共4页
Hash chain and its generalization—Multi-Dimensional Hash Chain (MDHC) have been widely used in the design of micropayment due to its simplicity and efficiency. In this letter, a more efficient variant of MDHC, called... Hash chain and its generalization—Multi-Dimensional Hash Chain (MDHC) have been widely used in the design of micropayment due to its simplicity and efficiency. In this letter, a more efficient variant of MDHC, called WMDHC, which endows in the structure of MDHC a weight value for each hash value through a well-defined mapping, is proposed. The average hash operation number of WMDHC is log(2 m / t ),which is better than log( m )of MDHC when the parameter t is typically suggested as t = 7. 展开更多
关键词 多空间闪光链 MDHC 加重平衡 计算机技术
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Synthesis and Crystal Structure of One-dimensional Chain Complexes [K(18-C-6)]_2[M(mnt)_2](M=Zn,Hg)
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作者 WANGDa-qi HEGuo-fang +1 位作者 QIULin-lin DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期263-268,共6页
The reactions of 18 crown 6 with each of K 2(M=Zn, Hg; mnt=1,2 dicyanoethene 1,2 dithiolate, C 2S 2(CN) 2- 2) were studied and novel complexes [K(18 C 6)] 2[Zn(mnt) 2](1) and [K(18 C 6)] 2[Hg(mnt)... The reactions of 18 crown 6 with each of K 2(M=Zn, Hg; mnt=1,2 dicyanoethene 1,2 dithiolate, C 2S 2(CN) 2- 2) were studied and novel complexes [K(18 C 6)] 2[Zn(mnt) 2](1) and [K(18 C 6)] 2[Hg(mnt) 2](2) were characterized by elemental analysis, IR spectrum and X ray diffraction analysis. Complex 1 displays a one dimensional chain of [K(18 C 6)] 2[Zn(mnt) 2] bridged by K O interactions between adjacent [K(18 C 6)] + units. Complex 2 is also a one dimensional chain of [K(18 C 6)] 2[Hg(mnt) 2] bridged by K...S weak interactions between adjacent [K(18 C 6)] + and [Hg(mnt) 2] 2- . 展开更多
关键词 One dimensional chain Crown ether mnt complex 18 Crown 6 Crystal structure
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Synthesis, structure, and properties of Ba9Co3Se(15) with one-dimensional spin chains
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作者 段磊 望贤成 +6 位作者 张俊 赵建发 曹立朋 李文敏 于润泽 邓正 靳常青 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期330-334,共5页
A new compound with one-dimensional spin chains, Ba9Co3Se(15), was synthesized under high pressure and high temperature conditions and systematically characterized via structural, transport and magnetic measurements. ... A new compound with one-dimensional spin chains, Ba9Co3Se(15), was synthesized under high pressure and high temperature conditions and systematically characterized via structural, transport and magnetic measurements. Ba9Co3Se(15) crystallizes in a hexagonal structure with the space group P-6c2(No. 188) and lattice constants of a = b = 9.6765 ? and c = 18.9562 ?. The structure consists of trimeric face-sharing octahedral CoSe6 chains, which are arranged in a triangular lattice in the ab-plane and separated by Ba atoms. The distance of the nearest neighbor of CoSe6 chains is very large, given by the lattice constant a = 9.6765 ?. The Weiss temperature Tθ associated with the intra-chain coupling strength is about -346 K. However, no long-range magnetic order but a spin glass transition at ~ 3 K has been observed. Our results indicate that the spin glass behavior in Ba9Co3Se(15) mainly arises from the magnetic frustration due to the geometrically frustrated triangular lattice. 展开更多
关键词 ONE-dimensionAL chain SPIN GLASS high-pressure
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Three-dimensional Motion of Multichain-Buoy Mooring System in shallow Water and Survival Conditions 被引量:1
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作者 Zhang Ting Sun Mingguang Graduate student, Department of Applied Mechanics and Engineering, Zhongshan University,Guangzhou 510275Professor, Department of Applied Mechanics and Engineering, Zhongshan University, Guangzhou 510275 《China Ocean Engineering》 SCIE EI 1997年第3期261-272,共12页
An engineering numerical model for three dimensional motion of multichain-buoy mooring system in shallow water and survival condition is given in this paper. Shooting-aim method is employed for solving the dynamic equ... An engineering numerical model for three dimensional motion of multichain-buoy mooring system in shallow water and survival condition is given in this paper. Shooting-aim method is employed for solving the dynamic equations of chain system in order to match the computation of buoy motion. The responses of buoy and chain have been computed for different wind-wave-current directions and different rigidity of chain. The results show that the present numerical model is reasonable. 展开更多
关键词 survival condition shallow water chain system three-dimensional motion
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Construction and Analysis of Three-dimensional Graphic Model of Single-chain Fv Derived from an Anti-human Placental Acidic Isoferritin Monoclonal Antibody by Computer 被引量:3
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作者 周春 沈关心 +4 位作者 朱慧芬 杨静 张悦 冯健南 沈倍奋 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2000年第1期23-25,共3页
Summary: A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (MAb) was construct- ed by a homologous protein... Summary: A three-dimensional (3D) graphic model of a single-chain Fv (scFv) which was derived from an anti-human placental acidic isoferritin (PAF) monoclonal antibody (MAb) was construct- ed by a homologous protein-predicting computer algorithm on Silicon graphic computer station. The structure, surface static electricity and hydrophobicity of scFv were investigated. Computer graphic modelling indicated that all regions of scFv including the linker, variable regions of the heavy (VH) and light (VL) chains were suitable. The VH region and the VL region were involved in composing the 'hydrophobic pocket'. The linker was drifted away VH and VL regions. The complementarity determining regions (CDRs) of VH and VL regions surrounded the 'hydrophobic pocket'. This study provides a theory basis for improving antibody affinity, investigating antibody structure and analyzing the functions of VH and VL regions in antibody activity. 展开更多
关键词 placental acidic isoferritin single-chain Fv three-dimensional structure com- puter modelling
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Synthesis and Crystal Structure of a New One-dimensional Double Helical-chain Polymer, {Zn(O_2CC_(12)H_8CO_2)(H_2O)}_n
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作者 YIN Pei-Xiu ZHANG Jian WEN Yi-Hang CHENG Jian-Kai LI Zhao-Ji YAO Yuan-Gen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第10期1107-1110,共4页
A new zinc polymer, {Zn(O2CC12H8CO2)(H2O)}, or {Zn(DPHA)(H2O)}n (O2CC12H8CO2, DPHA = 1,1′ -biphenyl-2,2′-dicarboxylate dianion) has been synthesized under hydrothermal conditions. The crystal is of monocli... A new zinc polymer, {Zn(O2CC12H8CO2)(H2O)}, or {Zn(DPHA)(H2O)}n (O2CC12H8CO2, DPHA = 1,1′ -biphenyl-2,2′-dicarboxylate dianion) has been synthesized under hydrothermal conditions. The crystal is of monoclinic, space group P21/c with a = 12.8418(5), b = 5.9505(2), c = 17.2989(5) A, β = 104.020(2)°, V = 1282.52(8) A^3, C14H10O5Zn, Mr= 323.61, Z = 4, Dc = 1.676 g/cm^3,μ = 1.930 mm^-1, F(000) = 656, R = 0.0766 and wR = 0.1871 for 1775 observed reflections (I 〉 2σ(I)). It consists of Zn2(DPHA)2(H2O)2 units, which are further extended into a one-dimensional double helical-chain polymer via Zn-O bonding. The hydrogen bonding interactions extend the helical chains into a two-dimensional layer structure. 展开更多
关键词 zinc polymer DPHA ligand one-dimensional double helical-chain two-dimensional layer structure
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Ground-State Energy and Entropy for One-Dimensional Heisenberg Chain with Alternating D-Term
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作者 Chunhuan Xiang Honglei Wang 《Journal of Applied Mathematics and Physics》 2019年第5期1220-1225,共6页
We study the ground-state information of one-dimensional Heisenberg chain with alternating D-term. Given the ground-state phase diagram, the ground-state energy and the entanglement entropy are obtained by tensor-net ... We study the ground-state information of one-dimensional Heisenberg chain with alternating D-term. Given the ground-state phase diagram, the ground-state energy and the entanglement entropy are obtained by tensor-net work algorithm. The phase transition points are shown in the entanglement entropy figure. The results are agreed with the phase diagram. 展开更多
关键词 GROUND-STATE Energy ENTROPY ONE-dimensionAL HEISENBERG chain
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MULTI-DIMENSIONAL MARKOV CHAIN–BASED ANALYSIS OF CONFLICT PROBABILITY FOR SPECTRUM RESOURCE SHARING
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作者 张轶 喻莉 张利维 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期207-215,共9页
In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimens... In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimensional Markov chain model is developed to analyze the performance of the proposed scheme. Meanwhile, performance metrics are derived. Numerical results show that the proposed scheme can effectively reduce the forced termination probability, blocking probability and spectrum utilization. 展开更多
关键词 multi-dimensional Markov chain model independent Poisson process negative exponential distribution forced termination probability blocking probability
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One-dimensional Vanadyl Phosphate Containing the Tancoite-like{Ⅴ^(Ⅳ)O(HPO_4)_2}^(2–)Chain
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作者 WEN Lei HUANG Ya-Xi +6 位作者 SUN Wei LIU Biao HUANG Chun-Zuo MI Jin-Xiao ZHUANG Rong-Chuan TANG Mei-Bo ZHAO Jing-Tai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第12期1821-1828,共8页
A vanadyl phosphate containing a new member of tancoite-like single chain, (DAPH2)[VIVO(HPO4)2]·xH20 (x ≈ 0.2, DAP = 1,3-diaminopropane, C3H10N2), has been synthesized under hydro(solvo)thermal condition... A vanadyl phosphate containing a new member of tancoite-like single chain, (DAPH2)[VIVO(HPO4)2]·xH20 (x ≈ 0.2, DAP = 1,3-diaminopropane, C3H10N2), has been synthesized under hydro(solvo)thermal conditions. It crystallizes in orthorhombic space group P21212 (No. 18) with a = 7.1730(14), b = 19.252(4), c = 8.6557(17) A, Z= 4, V= 1195.3(4)A3, C3H14.38N2P2VO9.19, Mr = 338.47, Dc = 1.881 g/cm3,μ(MoKa) = 1.138 mm-1 and F(000) = 692. The final full-matrix least-squares refinement converged to R = 0.0408, wR = 0.1046 for 2498 observed reflections with I 〉 2σ(I) and R = 0.0456 and wR = 0.1080 for all data (2750) and S = 1.001. Its one-dimensional 1 structure consists of tancoite-like ∞1 {vIVO(HPO4)2}2- single chains surrounded by DAPH22+ ions and water molecules. The single chain is built from trans-corner-sharing octahedral {VIV= O…VIV} backbone loop-branched by HPO4 groups like staple forming a new member of tancoite single chain. Due to the special coordination of VIVO6, the ∞1 {VO(HPO4)2-} chain adopts a larger M-O-M angle (V-O-V = 135°) than those of tancoite chains reported before. The corner-sharing linear {VIV = O…VIV} chain structure also leads to a one-dimensional weak antiferromagnetic interaction at low temperature. The magnetic measurements confirm the 4+ valence state of vanadium. IR and TG results of the title compound are also discussed. 展开更多
关键词 magnetic properties one-dimensional structure phosphate tancoite-like single chain VANADIUM
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基于ESTP-Chain四维分析法的老年福祉技术竞争态势分析 被引量:18
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作者 黄鲁成 常兰兰 +1 位作者 苗红 吴菲菲 《科技管理研究》 CSSCI 北大核心 2016年第12期213-219,共7页
针对我国现阶段对福祉技术的研究较少且主要集中于定性分析,缺乏数据支撑等问题,从定量的角度,在明确福祉技术定义的基础上,采用改进的ESTP-Chain四维分析法,分别从环境链,主体链、技术链和地位链四个维度,对该领域的国际竞争态势进行... 针对我国现阶段对福祉技术的研究较少且主要集中于定性分析,缺乏数据支撑等问题,从定量的角度,在明确福祉技术定义的基础上,采用改进的ESTP-Chain四维分析法,分别从环境链,主体链、技术链和地位链四个维度,对该领域的国际竞争态势进行分析。结果表明,ESTP-Chain四维分析法分析角度更为全面,能更好的揭示出福祉技术领域的竞争格局,为我国有效地适应老龄化社会的发展提供建议与支持。 展开更多
关键词 福祉技术 ESTP-chain四维分析法 竞争态势 老龄社会
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一般情况下一维三原子链的求解及其色散关系
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作者 成泓宣 胡建民 +1 位作者 王月媛 牛丽 《物理通报》 CAS 2024年第3期14-17,共4页
求解一般情况下一维三原子链的色散关系,讨论恢复力系数对色散关系的影响规律.研究结果表明,一般情况下一维三原子链不同的原子间恢复力系数对各支格波的频率、频谱宽度以及频率禁带宽度的影响规律均表现出不同特点,可实现对频率禁带宽... 求解一般情况下一维三原子链的色散关系,讨论恢复力系数对色散关系的影响规律.研究结果表明,一般情况下一维三原子链不同的原子间恢复力系数对各支格波的频率、频谱宽度以及频率禁带宽度的影响规律均表现出不同特点,可实现对频率禁带宽度的精细调节.本文的相关研究结果是对固体物理学基础理论的深入探讨,可为带通滤波器的工程设计提供理论指导. 展开更多
关键词 固体物理学 一维三原子链 色散关系 恢复力系数
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基于霍尔三维结构的农产品冷链物流供应链体系构建研究
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作者 魏雅琼 刘媛媛 《物流科技》 2024年第8期153-156,共4页
随着乡村振兴战略的实施,冷链物流成为畅通农产品产销渠道、建设农业强国、实现乡村振兴的重要保障。近些年,我国冷链物流市场规模逐渐扩大,基础设施日益完善,发展质量不断提升,推动了我国冷链物流体系的现代化建设。文章应用系统工程... 随着乡村振兴战略的实施,冷链物流成为畅通农产品产销渠道、建设农业强国、实现乡村振兴的重要保障。近些年,我国冷链物流市场规模逐渐扩大,基础设施日益完善,发展质量不断提升,推动了我国冷链物流体系的现代化建设。文章应用系统工程的霍尔三维结构论,从时间维、逻辑维、知识维系统分析了农产品冷链物流供应链体系,提出了构建我国冷链物流供应链体系的相关策略,为加快冷链物流高质量发展提供一定的参考。 展开更多
关键词 霍尔三维结构 冷链物流 供应链
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混联支路并联腿运动学分析与尺度综合
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作者 顾昌利 赵佳毅 +1 位作者 饶晓波 高建设 《机械设计与制造》 北大核心 2024年第3期94-99,共6页
针对步行机器人在核环境下作业时,动力源分散,不便于防护的问题,提出一种动力源集中布置,可用于构建步行机器人的四自由度混联支路并联腿部机构。运用螺旋理论分析其自由度数目、性质及机构特性。建立了运动学反解模型,并分别推导出驱... 针对步行机器人在核环境下作业时,动力源分散,不便于防护的问题,提出一种动力源集中布置,可用于构建步行机器人的四自由度混联支路并联腿部机构。运用螺旋理论分析其自由度数目、性质及机构特性。建立了运动学反解模型,并分别推导出驱动空间和关节空间的速度雅克比矩阵。以两个雅克比矩阵条件数为基础,提出了一种带权重的混合条件数,用于综合评价机构的力传递与运动传递性能。以混合条件数最小为尺度综合目标,先通过单调性分析得到结构参数的取值区间,再应用粒子群优化算法获得一组最优结构参数,为样机加工和其他混联支路并联机构尺度综合提供参考。该新型腿部机构动力源统一后置,便于集中防护,驱动空间具有驱动置换功能和半解耦特性,便于实现位姿控制,在核辐射、高温等恶劣环境下有着良好的应用前景。 展开更多
关键词 核机器人 混联支路 运动学分析 尺度综合 步行机器人
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正态分布规律下尺寸链设计分析
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作者 邓敬亮 刘才丽 劳贤豪 《航空发动机》 北大核心 2024年第1期164-169,共6页
为了提供尺寸链评判的量化依据、优化尺寸链关联尺寸的设计、降低零件加工成本,提出了一种新的基于正态分布规律的概率法尺寸链设计方法。通过概率法分析可知尺寸在设计公差范围内的分布规律服从正态分布,推导出在尺寸链中封闭环也服从... 为了提供尺寸链评判的量化依据、优化尺寸链关联尺寸的设计、降低零件加工成本,提出了一种新的基于正态分布规律的概率法尺寸链设计方法。通过概率法分析可知尺寸在设计公差范围内的分布规律服从正态分布,推导出在尺寸链中封闭环也服从正态分布,从而得出封闭环在设计要求区间内的概率值,进而评判机械装配中的间隙、干涉等是否具有合理性。结果表明:该尺寸链设计法可根据封闭环在设计要求区间的实际情况以概率值进行量化,从而使尺寸链设计的评判更加具体化;封闭环的区间概率值与尺寸链中的组成环可进行关联,因而对组成环的各零件尺寸进行调整优化,以提高封闭环的区间概率;对封闭环区间概率过低的情况,给出了在尺寸链中增加调整垫的设计方法和原则。 展开更多
关键词 尺寸链 概率法 正态分布 机械设计 封闭环 组成环 调整垫 航空发动机
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面向冷链智能立体仓库的数字孪生系统构建
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作者 胡斌 郭慧 陶雄杰 《包装工程》 CAS 北大核心 2024年第1期191-200,共10页
目的当前冷链物流行业立体仓库存在货品损耗率高、失温严重、信息化水平低等问题,确保冷链智能立体仓库的食品质量安全,并实现降本增效。方法面向冷链智能立体仓库的运行场景,设计全映射与多维仿真的数字孪生五维模型,通过对多源异构数... 目的当前冷链物流行业立体仓库存在货品损耗率高、失温严重、信息化水平低等问题,确保冷链智能立体仓库的食品质量安全,并实现降本增效。方法面向冷链智能立体仓库的运行场景,设计全映射与多维仿真的数字孪生五维模型,通过对多源异构数据的融合,实现立体仓库全要素的状态实时可视化与监测预警,并提出一种支持系统联动决策的模型优化策略,对立体库负载与温控区热力分布进行智能调节,最大限度提高运行效率和降低运营成本。结果构建了一套冷链智能立体仓库数字孪生系统,通过对优化前后仓库运行数据进行对比,同等仓储环境条件下生鲜蔬菜的食品保鲜度损耗率同比下降了25%~30%,实现了冷链智能立体仓库实时数据与动态虚拟模型的精准映射与联动运转。结论以广东某供应链管理有限公司佛山智能冷链仓储物流中心的冷链立体仓库为实践对象,形成了冷链智能立体仓库一体化管控新模式。为冷链智能立体仓库运营管理、调度联动决策与协同作业提供了数字孪生技术的应用参考,为建立更完善的保鲜产品包装与冷链食品质量安全提供了新路径。 展开更多
关键词 冷链物流 多维仿真 数字孪生 虚实联动
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平面尺寸链和空间尺寸链的计算方法
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作者 崔雷 王祖佩 《黄河科技学院学报》 2024年第5期40-46,共7页
当前在尺寸链计算方面存在着两个比较突出的问题:一是还没有一个简明易用并为大家所公认的既能计算直线尺寸链又能计算平面尺寸链和空间尺寸链的通用尺寸链计算方法;二是现有文献在计算尺寸的最大值和最小值时都是先算出尺寸的平均值和... 当前在尺寸链计算方面存在着两个比较突出的问题:一是还没有一个简明易用并为大家所公认的既能计算直线尺寸链又能计算平面尺寸链和空间尺寸链的通用尺寸链计算方法;二是现有文献在计算尺寸的最大值和最小值时都是先算出尺寸的平均值和公差,然后使平均值和偏差结合,从而得出尺寸的最大值和最小值。用这种方法时,为了计算公差须先算出一系列的公差传递系数,而计算传递系数的工作量大,很费时间。针对上述问题,提供了一组既能计算直线尺寸链又能计算平面尺寸链和空间尺寸链的算式,其中含有专门用于计算尺寸最大值和最小值的算式。利用此算式,不用计算平均尺寸、公差和传递系数,一个算式就能算出尺寸的最大值或最小值,从而节省计算时间、提高工作效率。为了说明算式的用法,列举了几个在工作中经常遇到的具有代表性的技术问题实例,涉及工序尺寸计算、坐标尺寸换算及工艺装备设计等方面。从涉及的尺寸链类型来看,有一维、二维、三维等3种尺寸链。 展开更多
关键词 尺寸链计算 平面尺寸链 空间尺寸链 增环 减环
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转向器部件预留间隙问题研究
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作者 张宝义 吴伟 万民伟 《现代制造技术与装备》 2024年第2期66-69,共4页
为解决某乘用车转向器各运动部件的装配预留间隙问题,分析转向器的结构和工作原理,对其关键部件建立计算机辅助工程(Computer Aided Engineering,CAE)模型进行受力模拟,研究传动机构游隙、配合件径向偏差、浮动功能及浮动量需求,进一步... 为解决某乘用车转向器各运动部件的装配预留间隙问题,分析转向器的结构和工作原理,对其关键部件建立计算机辅助工程(Computer Aided Engineering,CAE)模型进行受力模拟,研究传动机构游隙、配合件径向偏差、浮动功能及浮动量需求,进一步建立公差尺寸链,计算并分析封闭环目标极值公差。此外,提出一种产线上100%在线检测方法,以保证在产品实际生产装配过程中,将封闭环目标极值公差控制在0.1mm。 展开更多
关键词 转向器 预留间隙 游隙 计算机辅助工程(CAE)分析 尺寸链
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