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Acceleration of sheet metal spinning simulation by multi-mesh method
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作者 Zhuolei ZHAI Mei ZHAN +2 位作者 Zhipeng SHI Yunda DONG Xiaoguang FAN 《Chinese Journal of Aeronautics》 2025年第7期651-668,共18页
Sheet metal spinning is an incremental forming process for producing axisymmetric thinwalled parts through continuous local deformation under the action of rollers.While studying the spinning process by finite element... Sheet metal spinning is an incremental forming process for producing axisymmetric thinwalled parts through continuous local deformation under the action of rollers.While studying the spinning process by finite element(FE)method,a critical bottleneck is the enormous simulation time.For beating off this challenge,a novel multi-mesh method is developed.The method can dynamically track the movement of rollers and adaptively refine the mesh.Thus,a locally refined quadrilateral computation mesh can be generated in the locally-deforming zone and reduce the unnecessary fine elements outside the locally-deforming zone.In the multi-mesh system,the fine elements and coarse elements are extracted from a storage mesh and a background mesh,respectively.Meanwhile,the hanging nodes in the locally refined mesh are removed by designing 4-refinement templates.Between computation mesh and storage mesh,a bi-cubic parametric surface fitting algorithm and accurate remapping methods are conducted to transmit geometric information and physical fields.The proposed method has been verified by two spinning processes.The results suggest that the method can save time by up to about 67%with satisfactory accuracy,especially for distributions of thickness and strain compared with the fully refined mesh. 展开更多
关键词 spinNING Incremental forming Multi-mesh method Data remapping Adaptive remeshing ABAQUS
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Variational method based robust adaptive control for a guided spinning rocket 被引量:9
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作者 Zhongjiao Shi Liangyu Zhao Zhijie Liu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第3期164-175,共12页
In this paper,a robust adaptive controller is designed for a guided spinning rocket,whose dynamics presents the characteristics of pitch-yaw cross coupling,fast time-varying aerodynamics parameters and wide flight env... In this paper,a robust adaptive controller is designed for a guided spinning rocket,whose dynamics presents the characteristics of pitch-yaw cross coupling,fast time-varying aerodynamics parameters and wide flight envelop.First,a coupled nonlinear six-degree-of-freedom equation of motion for a guided spinning rocket is developed,and the lateral acceleration motion is modeled as a control plant with time-varying matched uncertainties and unmodeled dynamics.Then,a robust adaptive control method is proposed by combining Bregman divergence and variational method to achieve fast adaption and maintain bounded tracking.The stability of the resulting closed-loop system is proved,and the ultimate bound and convergence rate are also analyzed.Finally,numerical simulations are performed for a single operating point and the whole flight trajectory to show the robustness and adaptability of the proposed method with respect to timevarying uncertainties and unmodeled dynamics. 展开更多
关键词 Autopilot design Guided spinning rockets Robust adaptive control Second-order adaptive law Variational method
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Numerical simulation of single roller melt spinning for NdFeB alloy based on finite element method 被引量:2
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作者 Xu-Chao Wang Ming Yue +2 位作者 Dong-Tao Zhang Wei-Qiang Liu Ming-Gang Zhu 《Rare Metals》 SCIE EI CAS CSCD 2020年第10期1145-1150,共6页
The numerical simulation model of single roller melt spinning for rapid quenching process of NdFeB alloy was built,and the vacuum chamber,cooling roller and sample were taken into account as a system.The existing matu... The numerical simulation model of single roller melt spinning for rapid quenching process of NdFeB alloy was built,and the vacuum chamber,cooling roller and sample were taken into account as a system.The existing mature technology was in order to verify the correctness of simulation.The rapid quenching ribbons with different roll speeds were used as the simulation objects.The results of the numerical simulation and experiments show that the validity of the model has been testified and the reasons of the formation of complete quenching ribbons and by-product have been explained.The experimental thickness of the ribbons is proportional to the theoretical thickness.In the same spray condition,with the roll speed increasing,the thickness decreases linearly.At the speed range of25-30 m·s^(-1),the simulated calculation date is close to the experimental date,which can be considered as an ideal technological parameter. 展开更多
关键词 NDFEB Melt spinning Finite element method Numerical simulation
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THE DIVERGENT PROJECTIONS OF PERIPHERAL PROCESSES OF SUBSTANCE P-CONTAINING SPINAL GANGLIONIC NEURONS——Tri-labeled method of combining fluorescein tracing and immunocytochemistry 被引量:1
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作者 Liu Qingying Zhu Changgeng 《解剖学报》 CAS 1988年第3期336-336,共1页
The development of fluorescien double labeling method in recent years,has identified the peripheral processes of spinal ganglionic neurons project divergently to the somatic and visceral areas,but the chemical nature ... The development of fluorescien double labeling method in recent years,has identified the peripheral processes of spinal ganglionic neurons project divergently to the somatic and visceral areas,but the chemical nature of these neurons remains unknown.For this reason,we developed a tri-labeled method of combining fluorescein tracing and immunocytochemistry to clarify this problem. 展开更多
关键词 spin method labeled
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Preparation of Se-based solar cell using spin-coating method in ambient condition 被引量:1
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作者 朱孟花 邓雅心 +1 位作者 刘伟伟 李欣 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期64-67,共4页
A new hybrid organic-inorganic structure of FTO/TiO2/Se/HTL/Au based selenium solar cell has been fabricated through a low-cost spin-coating process in air. In this process, selenium is completely dissolved in hydrazi... A new hybrid organic-inorganic structure of FTO/TiO2/Se/HTL/Au based selenium solar cell has been fabricated through a low-cost spin-coating process in air. In this process, selenium is completely dissolved in hydrazine, to fk)rm a homogeneous precursor solution. After spin-coating the precursor solution on the TiO2 substrates, following by sintering at 200 ℃ for 5rain, a uniform selenium film with crystalline grains is formed. The selenium based solar cell exhibits an efficiency of 1.23% under AM1.5 illumination (100 mW.cm-2), short-circuit current density of 8 mA.cm 2, open-circuit voltage of 0.55 V, and fill factor of 0.37. Moreover, the device shows a stable ability with almost the same performance alter 60 days. 展开更多
关键词 spin-coating method SELENIUM solar cells
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Theory of phonon-modulated electron spin relaxation time based on the projection reduction method
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作者 Nam Lyong Kang Sang Don Choi 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期436-443,共8页
This paper introduces a new method for a formula for electron spin relaxation time of a system of electrons interacting with phonons through phonon-modulated spin-orbit coupling using the projection-reduction method. ... This paper introduces a new method for a formula for electron spin relaxation time of a system of electrons interacting with phonons through phonon-modulated spin-orbit coupling using the projection-reduction method. The phonon absorption and emission processes as well as the photon absorption and emission processes in all electron transition processes can be explained in an organized manner, and the result can be represented in a diagram that can provide intuition for the quantum dynamics of electrons in a solid. The temperature (T) dependence of electron spin relaxation times (T1) in silicon is T1 ∝ T-1.07 at low temperatures and T1 ∝ T-3.3 at high temperatures for acoustic deformation constant Pad = 1.4 × 10^7 eV and optical deformation constant Pod = 4.0 × 10^17 eV/m. This means that electrons are scattered by the acoustic deformation phonons at low temperatures and optical deformation phonons at high temperatures, respectively. The magnetic field (B) dependence of the relaxation times is T1 ∝ B-2.7 at 100 K and T1 ∝ B-2.3 at 150 K, which nearly agree with the result of Yafet, T1 ∝ B-3.0- B -2.5. 展开更多
关键词 electron spin resonance spin-orbit coupling projection-reduction method phonon scattering
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Energy Level of Coupled Harmonic Oscillator Model Born of Heisenberg Ferromagetic Spin Chain Derived by Invariant Eigen-operator Method
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作者 FAN Hong-Yi WU Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1177-1178,共2页
Based on the coupled harmonic oscillator model, which is born of Heisenberg ferromagnetic spin chain with nearest-neighbor interactions, we adopt the invariant eigen-operator method to derive its energy level, which p... Based on the coupled harmonic oscillator model, which is born of Heisenberg ferromagnetic spin chain with nearest-neighbor interactions, we adopt the invariant eigen-operator method to derive its energy level, which provides an alternate approach to dealing with the dynamics of spin chain. 展开更多
关键词 energy level spin chain IEO method
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Quantum Spin Liquid Phase in the Shastry–Sutherland Model Detected by an Improved Level Spectroscopic Method
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作者 Ling Wang Yalei Zhang Anders W.Sandvik 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期105-116,共12页
We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps betwe... We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena. 展开更多
关键词 red SSM Sutherland Model Detected by an Improved Level Spectroscopic method Quantum spin Liquid Phase in the Shastry Model
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Method of measuring rotation speed of high spinning projectile based on plane magnetic induction coil
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作者 CAO Yong-hong XUE Kai-yun JING Yong-qiang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第4期317-323,共7页
For the test of rotation speed of high spinning projectile, the general formula of the motional electromotive force (MEMF) of planar magnetic induction coil (PMIC) is derived in case of 3D rotation in a stable mag... For the test of rotation speed of high spinning projectile, the general formula of the motional electromotive force (MEMF) of planar magnetic induction coil (PMIC) is derived in case of 3D rotation in a stable magnetic field. Under a reasona-ble assumption, the MEMF of PMIC is simplified after the aforementioned general formula is used to calculate high spinning PMIC in the geomagnetic field environment. The determination approach of half-cycle is discussed and the method of rotation speed test is studied, and a test is conducted in the paper. The rotation speed curve obtained by the approach in this paper is consistent with the curve by telemetry. 展开更多
关键词 planar magnetic induction coil 3D rotation high spinning projectile determination approach of half-cycle rotation speed test method
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Structural, Optical and Luminescence Properties of ZnO Thin Films Prepared by Sol-Gel Spin-Coating Method: Effect of Precursor Concentration 被引量:1
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作者 R.Amari A.Mahroug +2 位作者 A.Boukhari B.Deghfel N.Selmi 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第1期63-67,共5页
Transparent zinc oxide(ZnO) thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations(0.3-1.2 M) using zinc acetate dehydrate [Zn(CH_3COO)_2&... Transparent zinc oxide(ZnO) thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations(0.3-1.2 M) using zinc acetate dehydrate [Zn(CH_3COO)_2·2H_2O] as precursor and isopropanol and monoethanolamine(MEA) as solvent and stabilizer, respectively. The molar ratio of zinc acetate dehydrate to MEA is 1.0. X-ray diffraction, ultraviolet-visible spectroscopy and photoluminescence spectroscopy are employed to investigate the effect of solution concentration on the structural and optical properties of the ZnO thin films. The obtained results of all thin films are discussed in detail and are compared with other experimental data. 展开更多
关键词 ZnO Optical and Luminescence Properties of ZnO Thin Films Prepared by Sol-Gel spin-Coating method Structural
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Achieving Ultralong Spin Coherent Time of Single Nitrogen Vacancy Centers in Diamond
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作者 Xiaoran Zhang Xinyu Zhuang Xiaobing Liu 《Chinese Physics Letters》 2025年第4期177-187,共11页
Single negatively charged nitrogen vacancy(NV-)centers in diamond have emerged as promising platforms for quantum information science,where long coherence times are essential for advancing quantum technologies.However... Single negatively charged nitrogen vacancy(NV-)centers in diamond have emerged as promising platforms for quantum information science,where long coherence times are essential for advancing quantum technologies.However,traditional fabrication methods often introduce lattice damage during the irradiation process used to create vacancies,significantly impairing the spin coherence properties of NV-centers. 展开更多
关键词 lattice damage nitrogen vacancy centers DIAMOND irradiation process ultralong spin coherent time fabrication methods spin coherence properties quantum information sciencewhere
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Electron Spin Resonance(ESR)Spectroscopy of the Transition-Metal Complexes and ClustersⅠ.Systematic Investigations of Real-and Complex-Orbital Methods for Calculating the d-Orbital Energies of a Low-Spin(S=1/2)nd^5(t_2~5,~2T_2
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作者 ZHAO Kun (Fujian Institute of Research on the Structure of Matter, the Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第1期71-80,共10页
A model of electronic intersupplemental states was presented for calculating the d orbital energies of a distorted octahedral low spin ( S =1/2) n d 5(t 5 2, 2T 2)(n=3, 4, 5) multielectron system... A model of electronic intersupplemental states was presented for calculating the d orbital energies of a distorted octahedral low spin ( S =1/2) n d 5(t 5 2, 2T 2)(n=3, 4, 5) multielectron system, and the 6 dimensional eigenmatrices of two new types in real and complex orbital representations were derived from this electron model forth. In comparison with real and complex orbital methods offered by the hole model, the real and complex orbital methods reported in this paper not only could give directly all the electronic structure parameters for the n d 5(t 5 2, 2T 2) multielectron system, but also showed many other new advantages such as standardization in theory, systematization in method, agreement in calculation and so on. 展开更多
关键词 ERS real and complex orbital methods low spin n d 5 system electronic intersupplemental state
全文增补中
TRANSFER-MATRIX METHOD FOR SURFACE SPIN WAVES IN A SEMI-INFINITE MAGNETIC SUPERLATTICE WITH A SINGLE-ION ANISOTROPY
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作者 李振亚 沈文忠 《苏州大学学报(自然科学版)》 CAS 1992年第2期176-184,共9页
Surface spin waves in a semi-infinite magnetre super lattice with a single-ion uniaxial anisotropy are investigated through the transfer mafrix method.The dispersion equations of surface spin wavs are obfained.We find... Surface spin waves in a semi-infinite magnetre super lattice with a single-ion uniaxial anisotropy are investigated through the transfer mafrix method.The dispersion equations of surface spin wavs are obfained.We find that not all the magnetic superlattice structures can excite the surface spin waves,and that the anisotropy term need not be favorable to the excitation of surface spin wavs,but surely influences the values of the energy of the excited surface spin waves. 展开更多
关键词 转移矩阵法 表面旋转波 超点阵 磁性材料 各向异性 离子
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Review on hot spinning for difficult-to-deform lightweight metals 被引量:18
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作者 詹梅 杨合 +1 位作者 郭靖 王贤贤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1732-1743,共12页
Hot spinning process has attracted significant attention because it can be used to manufacture complex parts, extend the forming limit of materials, decrease forming forces and reduce process chains. In this paper, we... Hot spinning process has attracted significant attention because it can be used to manufacture complex parts, extend the forming limit of materials, decrease forming forces and reduce process chains. In this paper, we review researches on lightweight metals spun at elevated temperatures since they are difficult to deform at room temperature. These metals include light alloys, such as titanium, magnesium and aluminum alloys, and metal composites. Then, the heating methods used in the hot spinning process and the treatment methods employed for the temperature boundary condition in finite element analyses for the process were discussed. Finally, the future development directions for the hot spinning process of lightweight but difficult-to-deform alloys were highlighted. 展开更多
关键词 hot spinning lightweight metal heating method temperature boundary condition future develonment direction
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Finite element simulation of ball spinning of NiTi shape memory alloy tube based on variable temperature field 被引量:2
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作者 江树勇 张艳秋 +2 位作者 赵亚楠 唐明 李春峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期781-787,共7页
As a new attempt,ball spinning was used to manufacture the nickel-titanium shape memory alloy(NiTi SMA) tube at elevated temperature.The NiTi bar with a nominal composition of Ni50.9Ti49.1(mole fraction,%) was sol... As a new attempt,ball spinning was used to manufacture the nickel-titanium shape memory alloy(NiTi SMA) tube at elevated temperature.The NiTi bar with a nominal composition of Ni50.9Ti49.1(mole fraction,%) was solution treated and was used as the original tube blank for ball spinning.Based on the variable temperature field and the constitutive equation,rigid-viscoplastic finite element method(FEM) was applied in order to simulate the ball spinning of NiTi SMA tube.The temperature field,the stress field,the strain field and the load prediction were obtained by means of FEM.FEM results reveal that there is a temperature increase of about 160 ℃ in the principal deformation zone of the spun part.It can be found from the stress fields and the strain fields that the outer wall of NiTi SMA tube is easier to meet the plastic yield criterion than the inner wall,and the plastic deformation zone is caused to be in a three-dimensional compressive stress state.The radial strain and the tangential strain are characterized by the compressive strain,while the axial strain belongs to the tensile strain.The variation of spinning loads with the progression of the ball is of great importance in predicting the stable flow of the spun part. 展开更多
关键词 NiTi alloy NiTi tube shape memory alloy finite element method ball spinning
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基于SPIN的Andrew Secure RPC协议并行攻击模型检测 被引量:2
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作者 肖美华 朱科 马成林 《计算机科学》 CSCD 北大核心 2015年第7期103-107,共5页
Andrew Secure RPC协议具有身份认证和秘钥交换功能,其因简洁明了而被广泛应用于对称密钥加密体系中。模型检测技术具有高度自动化的优点,在协议安全性验证领域得到广泛应用,但模型检测方法只能检测到一轮协议会话中存在的攻击,难以检... Andrew Secure RPC协议具有身份认证和秘钥交换功能,其因简洁明了而被广泛应用于对称密钥加密体系中。模型检测技术具有高度自动化的优点,在协议安全性验证领域得到广泛应用,但模型检测方法只能检测到一轮协议会话中存在的攻击,难以检测到多轮并行会话中存在的并行攻击。针对Andrew Secure RPC协议运行环境中存在的并行性与可能出现的安全隐患,提出了组合身份建模方法。该方法运用著名的SPIN模型检测工具,对Andrew Secure RPC协议进行模型检测,从而得到攻击序列图,成功发现并行反射攻击和类缺陷攻击。上述组合身份建模方法为复杂环境下协议的模型检测提供了新的方向。 展开更多
关键词 ANDREW SECURE RPC协议 模型检测 spin 组合身份建模 并行攻击
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利用SPIN实现对OpenFlow协议的形式化验证 被引量:2
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作者 石颖 《计算机安全》 2014年第3期38-43,共6页
为了验证OpenFlow网络中网络控制器NOX系统内典型应用程序Pyswitch的正确性,采用Promela语言对经简化的OpenFlow网络中的网络元素、连接通道及拓扑结构进行建模,并使用SPIN工具对所建模型进行形式化验证。结果表明,Pyswitch在主机不发... 为了验证OpenFlow网络中网络控制器NOX系统内典型应用程序Pyswitch的正确性,采用Promela语言对经简化的OpenFlow网络中的网络元素、连接通道及拓扑结构进行建模,并使用SPIN工具对所建模型进行形式化验证。结果表明,Pyswitch在主机不发生移动的情况下结果正确,但在主机发生移动情况下,会由于pyswitch的MAC地址学习算法存在设计缺陷而产生错误。 展开更多
关键词 OpenFlow网络 spin工具 Pyswitch程序 建模 形式化 验证
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基于混合式教学法的翻转课堂教学模式探讨——以推销学SPIN销售法为例 被引量:1
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作者 沈滔 《佳木斯职业学院学报》 2017年第9期37-38,共2页
结合高职市场营销课程特色,适应高职学生学情特点,在推销学中引入翻转课堂教学模式,以混合式教学法将线上教学与线下教学有效结合,取得了较好的效果。本研究通过混合式翻转课堂模式在SPIN销售法的应用实践,为高职市场营销专业课教学提... 结合高职市场营销课程特色,适应高职学生学情特点,在推销学中引入翻转课堂教学模式,以混合式教学法将线上教学与线下教学有效结合,取得了较好的效果。本研究通过混合式翻转课堂模式在SPIN销售法的应用实践,为高职市场营销专业课教学提供有价值的思路建议。 展开更多
关键词 混合式教学法 翻转课堂 信息化教学 spin销售法
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基于SPIN的HMSC模型自动检验方法
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作者 李立亚 孙雨荷 +2 位作者 马汉杰 丁佐华 黄鸿云 《计算机工程与设计》 北大核心 2023年第10期3047-3055,共9页
自动检测与验证HMSC(high-level message sequence chart)模型的正确性对保证文本需求被正确建模具有十分重要的意义,为此提出一种为HMSC模型进行自动检验的方法,并将其实现。利用转换规则为HMSC模型生成Promela检测语言,借助SPIN工具... 自动检测与验证HMSC(high-level message sequence chart)模型的正确性对保证文本需求被正确建模具有十分重要的意义,为此提出一种为HMSC模型进行自动检验的方法,并将其实现。利用转换规则为HMSC模型生成Promela检测语言,借助SPIN工具对需求进行验证。该方法不仅支持模型检测,同时通过对系统行为的动态模拟可以实现需求的合理性分析。从Promela实现到SPIN验证整个过程实现自动化操作。在该方法的基础上实现一个文本需求自动建模及检测分析的工具,通过一个实例展示其自动建模检测分析的效果,表明了其有效性和实用性。 展开更多
关键词 模型检测 HMSC模型 spin工具 正确性验证 模型转换 Promela语言 形式化方法
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ANALYSIS OF MECHANICS IN BALL SPINNING OF THIN-WALLED TUBE 被引量:17
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作者 JIANG Shuyong REN Zhengyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期25-30,共6页
Ball spinning is applied to manufacturing thin-walled tube with high precision and high mechanical properties.On the basis of plastic mechanics,by simplifying ball spinning of thin-walled tube as plane strain problem,... Ball spinning is applied to manufacturing thin-walled tube with high precision and high mechanical properties.On the basis of plastic mechanics,by simplifying ball spinning of thin-walled tube as plane strain problem,slab method is used for the purpose of calculating the contact deformation pressure.The spinning force components,the torsional moment,the deformation power and the deformation work are calculated further as well.The influence of the two important process parameters such as the feed ratio and the ball diameter on the spinning force components is analyzed in order to further control the spinning force components by regulating the two process variables during the ball spinning process.The stress and strain state in deformable zone as well as mechanics boundary conditions in ball spinning are obtained.The effect of the three spinning force components on the formability of the spun part is analyzed and validated through the ball spinning experiments.The theoretical and experimental results show that the radial spinning component plays a significant role in ball spinning of thin-walled tube,and the mechanics situation in backward ball spinning contributes to enhancing the plasticity of the metal material,but that in forward ball spinning contributes to advancing the axial flow of the metal material. 展开更多
关键词 Power spinning Tube spinning Ball spinning spinning force Slab method
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