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THE BOUNDARY SCHWARZ LEMMA AND THE RIGIDITY THEOREM ON REINHARDT DOMAINS B_(p)^(n) OF C^(n)
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作者 王建飞 张艳慧 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期839-850,共12页
By introducing the Carathéodory metric,we establish the Schwarz lemma at the boundary for holomorphic self-mappings on the unit p-ball B_(p)^(n) of C^(n).Furthermore,the boundary rigidity theorem for holomorphic ... By introducing the Carathéodory metric,we establish the Schwarz lemma at the boundary for holomorphic self-mappings on the unit p-ball B_(p)^(n) of C^(n).Furthermore,the boundary rigidity theorem for holomorphic self-mappings defined on B_(n)^(p) is obtained.These results cover the boundary Schwarz lemma and rigidity result for holomorphic self-mappings on the unit ball for p=2,and the unit polydisk for p=∞,respectively. 展开更多
关键词 Schwarz lemma Carathéodory metric rigidity
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Rigidity Symmetry Line for Thermodynamic Fluid Equations-of-State
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作者 Leslie V. Woodcock 《Journal of Modern Physics》 2024年第5期613-633,共21页
We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by perco... We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO<sub>2</sub>, H<sub>2</sub>O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)<sub>T</sub>, between gaseous and liquid states along any isotherm from critical (T<sub>c</sub>) to Boyle (T<sub>B</sub>) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we investigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρ<sub>rs</sub>(T) = RT) to gas phase virial coefficients. We show that it is continuous in all derivatives, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)<sub>T</sub> = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρ<sub>BW</sub>(T) = 2ρ<sub>PA</sub>(T) = 3ρ<sub>PB</sub>(T) = 3ρ<sub>RS</sub>(T)/2 for T T<sub>B</sub>. These simple relationships arise, because the higher virial coefficients (b<sub>n</sub>, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T T<sub>B</sub>)<sub> </sub>within the gas phase. The Boyle-work line (p/ρ<sub>BW</sub>)<sub>T</sub> is related exactly at lower densities as T → T<sub>B</sub>, and accurately for liquid densities, by ρ<sub>BW</sub>(T) = −(b<sub>2</sub>/b<sub>3</sub>)<sub>T</sub>. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρ<sub>RS</sub>(0) = (2/3)ρ<sub>BW</sub>(0) for argon). Given the gas-liquid rigidity symmetry, the entire thermodynamic state functions below T<sub>B</sub> are obtainable from b<sub>2</sub>(T). A BW-line ground-state crystal density ρ<sub>BW</sub>(0) can be defined by the pair potential minimum. The Ar<sub>2</sub> pair potential, ∅ij</sub>(r<sub>ij</sub>) determines b<sub>2</sub>(T) analytically for all T. This report, therefore, advances the salient objective of liquid-state theory: an argon p(ρ,T) Equation-of-state is obtained from ∅<sub>ij</sub>(r<sub>ij</sub>) for all fluid states, without any adjustable parameters. 展开更多
关键词 Liquid-State Theory Cluster Physics Percolation Lines Fluid Thermodynamics Boyle Line rigidity-Symmetry Line
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Impairment of rigidity sensing caused by mutant TP53 gain of function in osteosarcoma
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作者 Ming Luo Mingyang Huang +5 位作者 Ningning Yang Yufan Zhu Peng Huang Zhujun Xu Wengang Wang Lin Cai 《Bone Research》 SCIE CAS CSCD 2023年第2期416-426,共11页
Osteosarcoma(OS)is the most common primary malignant pediatric bone tumor and is characterized by high heterogeneity.Studies have revealed a wide range of phenotypic differences among OS cell lines in terms of their i... Osteosarcoma(OS)is the most common primary malignant pediatric bone tumor and is characterized by high heterogeneity.Studies have revealed a wide range of phenotypic differences among OS cell lines in terms of their in vivo tumorigenicity and in vitro colony-forming abilities.However,the underlying molecular mechanism of these discrepancies remains unclear.The potential role of mechanotransduction in tumorigenicity is of particular interest.To this end,we tested the tumorigenicity and anoikis resistance of OS cell lines both in vitro and in vivo.We utilized a sphere culture model,a soft agar assay,and soft and rigid hydrogel surface culture models to investigate the function of rigidity sensing in the tumorigenicity of OS cells.Additionally,we quantified the expression of sensor proteins,including four kinases and seven cytoskeletal proteins,in OS cell lines.The upstream core transcription factors of rigidity-sensing proteins were further investigated.We detected anoikis resistance in transformed OS cells.The mechanosensing function of transformed OS cells was also impaired,with general downregulation of rigidity-sensing components.We identified toggling between normal and transformed growth based on the expression pattern of rigidity-sensing proteins in OS cells.We further uncovered a novel TP53 mutation(R156P)in transformed OS cells,which acquired gain of function to inhibit rigidity sensing,thus sustaining transformed growth.Our findings suggest a fundamental role of rigidity-sensing components in OS tumorigenicity as mechanotransduction elements through which cells can sense their physical microenvironment.In addition,the gain of function of mutant TP53 appears to serve as an executor for such malignant programs. 展开更多
关键词 TP53 IMPAIRED rigidity
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GLOBAL RIGIDITY THEOREMS FOR SUBMANIFOLDS WITH PARALLEL MEAN CURVATURE
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作者 潘鹏飞 许洪伟 赵恩涛 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期169-183,共15页
In this paper,we mainly study the global rigidity theorem of Riemannian submanifolds in space forms.Let Mn(n≥3)be a complete minimal submanifold in the unit sphere Sn+p(1).Forλ∈[0,n2−1/p),there is an explicit posit... In this paper,we mainly study the global rigidity theorem of Riemannian submanifolds in space forms.Let Mn(n≥3)be a complete minimal submanifold in the unit sphere Sn+p(1).Forλ∈[0,n2−1/p),there is an explicit positive constant C(n,p,λ),depending only on n,p,λ,such that,if∫MSn/2dM<∞,∫M(S−λ)n/2+dM<C(n,p,λ),then Mn is a totally geodetic sphere,where S denotes the square of the second fundamental form of the submanifold and∫+=max{0,f}.Similar conclusions can be obtained for a complete submanifold with parallel mean curvature in the Euclidean space Rn+p. 展开更多
关键词 Euclidean space the unit sphere submanifolds with parallel mean curvature global rigidity theorem
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Interaction Mechanisms between Natural Debris Flow and Rigid Barrier Deflectors:A New Perspective for Rational Design and Optimal Arrangement
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作者 Yu Huang Beilei Liu +1 位作者 Dianlei Feng Hao Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1679-1699,共21页
Rigid barrier deflectors can effectively prevent overspilling landslides,and can satisfy disaster prevention requirements.However,the mechanisms of interaction between natural granular flow and rigid barrier deflector... Rigid barrier deflectors can effectively prevent overspilling landslides,and can satisfy disaster prevention requirements.However,the mechanisms of interaction between natural granular flow and rigid barrier deflectors require further investigation.To date,few studies have investigated the impact of deflectors on controlling viscous debris flows for geological disaster prevention.To investigate the effect of rigid barrier deflectors on impact mechanisms,a numerical model using the smoothed particle hydrodynamics(SPH)method with the Herschel–Bulkley model is proposed to simulate the interaction between natural viscous flow and single/dual barriers with and without deflectors.This model was validated using laboratory flume test data from the literature.Then,the model was used to investigate the influence of the deflector angle and multi-barrier arrangements.The optimal configuration of multi-barriers was analyzed with consideration to the barrier height and distance between the barriers,because these metrics have a significant impact on the viscous flow pile-up,run-up,and overflow mechanisms.The investigation considered the energy dissipation process,retention efficiency,and dead-zone formation.Compared with bare barriers with similar geometric characteristics and spatial distribution,rigid barriers with deflectors exhibit superior effectiveness in preventing the overflow and overspilling of viscous debris flow.Recommendations for the rational design of deflectors and the optimal arrangement of multi-barriers are provided to mitigate geological disasters. 展开更多
关键词 rigid barrier deflectors deflector angle single-barrier dual-barrier arrangements viscous debris flow over-spilling delta-plus-SPH
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Condition indices for rigid pavements: A comparative analysis of state DOTs using Michigan PMS data
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作者 Rahul Raj Singh Mumtahin Hasnat +3 位作者 Muhammed Emin Kutay Syed Waqar Haider James Bryce Bora Cetin 《Journal of Road Engineering》 2024年第3期348-360,共13页
Pavement infrastructure is vital in providing services and links between various sectors of society. Therefore, thepreservation and maintenance of these roads are critical to attaining a pavement network in good condi... Pavement infrastructure is vital in providing services and links between various sectors of society. Therefore, thepreservation and maintenance of these roads are critical to attaining a pavement network in good conditionthroughout its service life. Various performance indicators like the international roughness index (IRI), pavementcondition index (PCI), and present serviceability rating (PSR) have been used by the state department of transportation (DOT) and highway agencies for evaluating pavement surface conditions and planning future maintenance strategies. Limited data availability, multiple distresses depending on region, lack of correlation of thesecondition indices to maintenance strategies, and data collection limitations pose a challenge for applying theseindices to local conditions. This paper compares condition indices of different states for rigid pavements. Further,using a specific condition index for local conditions is also highlighted. For this purpose, five states and theircorresponding condition indices were evaluated and compared to the Michigan DOT distress index (DI). Thesestates include Virginia, Minnesota, North Dakota, Louisiana, and Oregon. The corresponding distresses of eachcondition index were converted to make them compatible with the MDOT DI. This study used the MDOT'spavement management system (PMS) database to evaluate each condition index for 433 rigid pavement sections.Each distress index was plotted against MDOT DI and compared using a paired t-test. Results show that thecondition indices of Virginia and Minnesota are comparable to DI in terms of the Spearman correlation value. Thet-test results show that except for Virgina, condition indices from other states statistically differ from DI.Therefore, one can't use those directly for local conditions in Michigan. This paper presents the evaluation anddata requirements for each condition index and its impact on selecting a maintenance treatment. 展开更多
关键词 rigid pavement Pavement management Condition index Distress index
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Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge
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作者 Xilong Zheng Qiong Wang Di Guan 《Structural Durability & Health Monitoring》 EI 2024年第3期361-376,共16页
The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation ... The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively. 展开更多
关键词 Continuous rigid frame bridge REHABILITATION long-term monitoring field load test safety standard determination
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Radial Grip Rigidity of the Matching of Lengthened Shrink-fit Holder and Cutter in High-speed Milling 被引量:5
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作者 ZHOU Houming WANG Chengyong +1 位作者 DENG Jianxin PENG Ruitao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第1期179-183,共5页
Though the lengthened shrink-fit holder (LSFH) is widely applied in high speed milling of the parts characterized by deep cavities at present, its design and selection mainly depends on the experience and lacks a corr... Though the lengthened shrink-fit holder (LSFH) is widely applied in high speed milling of the parts characterized by deep cavities at present, its design and selection mainly depends on the experience and lacks a correct theoretical guidance. In this paper, attention is focus on the radial grip rigidity of the matching of LSFH and cutter in high speed milling. Based on the experiment modal analysis (EMA) technique, an accurate finite element model of the matching of LSFH and cutter is established firstly. Subsequently, the influence of different interference, grip length and spindle speed on the grip rigidity of LSFH are analyzed. The analysis results show that there is a reasonable interference and grip length between the LSFH and cutter so that to have a steepless grip and have a good radial grip rigidity and at the same time to avoid the strength of LSFH to exceed it’s yield limit which will reduce the precision and service life of LSFH, besides when spindle speed reach a extension the weakening influence of the centrifugal force on the radial grip rigidity of the matching of LSFH and cutter should been taken into account. Finally, the finite element analysis results are verified based on the construction of measurement method of the grip rigidity and the results fit very well. The studies provide a theoretical basis for the design, selection and the serialization and standardization of the matching of LSFH and cutter. 展开更多
关键词 Lengthened shrink-fit holder Finite element analysis Radial grip rigidity High speed milling
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Theoretical analysis of natural frequency of externally prestressed concrete beam based on rigidity correction 被引量:3
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作者 Hui-xia Xiong1,2, Yao-ting Zhang11.School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan 430074, China 2.Department of Civil Engineering, Nanyang Institute of Technology, Nanyang 473004, China. 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第1期31-35,共5页
A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase w... A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula. 展开更多
关键词 externally prestressed concrete beam natural frequency rigidity correction regression analysis
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On rigidity of Clifford torus in a unit sphere 被引量:2
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作者 XU Yi-wen XU Zhi-yuana 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期121-126,共6页
We extend the scalar curvature pinching theorems due to Peng-Terng, Wei-Xu and Suh-Yang. Let M be an n-dimensional compact minimal hypersurface in S^n+1 satisfying S f4 - f^2 3 ≤1/nS^3 where S is the squared norm of... We extend the scalar curvature pinching theorems due to Peng-Terng, Wei-Xu and Suh-Yang. Let M be an n-dimensional compact minimal hypersurface in S^n+1 satisfying S f4 - f^2 3 ≤1/nS^3 where S is the squared norm of the second fundamental form of M, and fk = ∑λi^k and λi(1 ≤ i ≤ n) are the principal curvatures of M. We prove that there exists a positive constant δ(n)(≥ n/2) depending only on n such that if n ≤ S ≤ n +δ(n), then S ≡ n, i.e., M is one of the Clifford torus S^K (√k/n) × S^n-k (V√n-k/n) for 1≤ k ≤ n - i. Moreover, we prove that if S is a constant, then there exists a positive constant T(n)(≥ n -2/3) depending only on n such that ifn ≤ S 〈 n + τ(n), then S ≡n, i.e.. M is a Clifford torus. 展开更多
关键词 Minimal hypersurface rigidity scalar curvature second fundamental form Clifford torus.
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Numerical evaluation of buckling behavior in space structure considering geometrical parameters with joint rigidity 被引量:7
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作者 Su-Deok Shon Kyung-Ju Hwang Seung-Jae Lee 《Journal of Central South University》 SCIE EI CAS 2014年第3期1115-1124,共10页
The buckling behavior of single layer space structure is very sensitive. The joint rigidity, moreover, is one of the main factors of stability which may determine the entire failure behavior. Thus, the reasonable stif... The buckling behavior of single layer space structure is very sensitive. The joint rigidity, moreover, is one of the main factors of stability which may determine the entire failure behavior. Thus, the reasonable stiffness of joint system, which is neither total pin assumption nor perfect fix condition, is very important to apply to the real single layer space one. Therefore, the purpose of this work was to investigate the buckling behavior of single layer space structure, using the development of the upgraded stiffness matrix for the joint rigidity. To derive tangential stiffness matrix, a displacement function was assumed using translational and rotational displacement at the node. The geometrical nonlinear analysis was simulated not only with perfect model but also with imperfect one. As a result, the one and two free nodal numerical models were investigated using derived stiffness matrix. It was figured out that the buckling load increases in proportion to joint rigidity with rise-span ratio. The stability of numerical model is very sensitive with the initial imperfection, responding of bifurcation in the structure. 展开更多
关键词 space frame geometric nonlinearity SNAP-THROUGH BIFURCATION initial imperfection joint rigidity
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Chain Conformation and Local Rigidity of Soluble Polyimides(II):Isomerized Polyimides in THF 被引量:2
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作者 LIU Gui-hua QIU Xue-peng +1 位作者 BO Shu-qin JI Xiang-ling 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期329-333,共5页
Two soluble isomerized polyimides(PIs) synthesized from 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA) with either 2,2'-dimethylbenzidine(2,2'-DMB) or 3,3'-DMB were investigated by means ... Two soluble isomerized polyimides(PIs) synthesized from 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA) with either 2,2'-dimethylbenzidine(2,2'-DMB) or 3,3'-DMB were investigated by means of size-exclusion chromatography coupled with multi-angle laser light scattering,a viscometer and a refractive index detector in tetrahydrofuran(THF) with tetrabutylammonium bromide(TBAB) at 35 ℃.The corresponding parameters related to conformations α and ν,evaluated from the scaling relationships [η]=K η M α and R g =K g M ν,respectively,were 0.66±0.01 and 0.55±0.02 for poly(6FDA/3,3'-DMB),and 0.67±0.01 and 0.56±0.01 for poly(6FDA/2,2'-DMB),indicating a random coil conformation for both the samples in this mobile system.The persistence length l p and shift factor M L(relative molecular weight per unit contour length) were estimated from the relationship between intrinsic viscosity and molecular weight for the wormlike cylinder model proposed by Bohdanecky.Both l p and M L showed that the two PIs in THF are flexible chains and exhibit some local rigidity to some extent. 展开更多
关键词 Isomerized polyimide Chain conformation Local rigidity Wormlike chain Persistence length
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Relation between Stress Conditions, Uncertainty and Incongruity Intolerance, Rigidity and Mental Health: Experimental Demonstrations 被引量:2
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作者 Valeria Biasi Paolo Bonaiuto James M. Levin 《Health》 2015年第1期71-84,共14页
An innovative critique of existing studies on creativity has revealed the opportunity of distinguishing between different varieties of creative tasks, and namely creativity for “Continuity”, “Opposition” and “Det... An innovative critique of existing studies on creativity has revealed the opportunity of distinguishing between different varieties of creative tasks, and namely creativity for “Continuity”, “Opposition” and “Detachment”, considering relations between products and perceived models. This theoretical contribution has led to a specific evaluation procedure: the COD Creativity test. Considering the influences of dynamic processes on creative processes, it is worth experimentally studying the effects of short-term stress or comfort treatments. The similarities and differences between various existing studies are examined. A non-invasive but effective procedure, compared to classic techniques, is described: the “drawing recall” of stressful or relaxing real experiences, accompanied by detailed evaluations of the emotional sphere. In a specific investigation, creativity turned out to be significantly lower after acute stress with respect to comfort treatment. In conclusion, the cognitive, decisional and activity processes involved in creativity operations can be considered as strictly reflecting emotional dynamic processes, as well as the experiences gained during the stress or comfort treatments. Results are explained considering the role of conflict overload in stress as a factor of incongruity and uncertainty intolerance, inhibiting the production of bizarre and unusual ideas and configurations, and thus reducing essential aspects relevant to the evaluation of creativity levels. From clinical point of view, we underline that decades of research has generally shown that being more rigid is associated with poorer mental health. Our experimental study gives confirmation of the link between stress and intolerance of uncertainty and incongruity;this correlation could augment the negative impact of stressors on anxiety levels. In summary, people with high level of intolerance of uncertainty and, generally, with high level of intolerance of incongruity, develop mental rigidity, and this traits constellation represent a risk for mental health. 展开更多
关键词 CREATIVITY UNCERTAINTY and INCONGRUITY INTOLERANCE MENTAL Health rigidity Stress
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CALCULATION OF MILL RIGIDITY BY THREE DIMENSION CONTACT BOUNDARY ELEMENT METHOD 被引量:1
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作者 Shu Xuedao Zhang Liandong Shen Gangxian Rolling Mill Institute,Yanshan University Gao Lihua Beiman Special Type Steel Stock Corporation Ltd. 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第1期82-85,共4页
Vertical rigidity of the space self adaptive 530 high rigidity mill is calculated by applying the boundary element method (BEM) of three dimension elastic contact problem,which can update the existed deforming s... Vertical rigidity of the space self adaptive 530 high rigidity mill is calculated by applying the boundary element method (BEM) of three dimension elastic contact problem,which can update the existed deforming separation calculating theory and corresponding methods of material mechanics,elastic mechanics and finite element method.The method has less hypotheses and stronger synthesis in contact type calculating model.The advantages of the method are high calculating rate,high calculating accuracy,etc.. 展开更多
关键词 Mill rigidity Boundary element method Deforming separation CONTACT type
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Research on the Structural Rigidity Characteristics of a Reconfigurable TBM Thrust Mechanism 被引量:3
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作者 Younan Xu Xinjun Liu Jiyu Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第6期35-47,共13页
To improve the adaptability of TBMs in diverse geological environments,this paper proposes a reconfigurable Type-V thrust mechanism(V-TM)with rearrangeable working states,in which structural stiffness can be automatic... To improve the adaptability of TBMs in diverse geological environments,this paper proposes a reconfigurable Type-V thrust mechanism(V-TM)with rearrangeable working states,in which structural stiffness can be automatically altered during operation.Therefore,millions of configurations can be obtained,and thousands of instances of working status per configuration can be set respectively.Nonetheless,the complexity of configurations and diversity of working states contributes to further complications for the structural stiffness algorithm.This results in challenges such as difficulty calculating the payload compliance index and the environment adaptability index.To solve this problem,we use the configuration matrix to describe the relationship between propelling jacks under reconfiguration and adopt pattern vectors to describe the working state of each hydraulic cylinder.Then,both the dynamic compatible equation between propeller forces of the hydraulic cylinders and driving forces,and the kinematic harmonizing equation between the hydraulic cylinder displacements and their deformations are established.Next,we derive the stiffness analytical equation using Hooke’s law and the Jacobian Matrix.The proposed approach provides an effective algorithm to support structural rigidity analysis,and lays a solid theoretical foundation for calculating the performance indexes of the V-TM.We then analyze the rigidity characteristics of typical configurations under different working states,and obtain the main factors affecting structural stiffness of the V-TM.The results show the deviation degree of structural parameters in hydraulic cylinders within the same group,and the working status of propelling jacks.Finally,our constructive conclusions contribute valuable information for matching and optimization by drawing on the factors that affect the structural rigidity of the V-TM. 展开更多
关键词 Reconfigurable TBM thrust mechanism Structural rigidity characteristics Configuration matrix Patternvector Kinematic harmonizing equation Dynamic compatible equation Structural stiffness equations
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An optimal rigidity theorem for complete submanifolds in a sphere 被引量:1
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作者 XU Hong-wei ZHU Jiao-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期219-226,共8页
It is proved that if M^n is an n-dimensional complete submanifold with parallel mean curvature vector and flat normal bundle in S^n+p(1), and if supM S 〈 α(n, H), where α(n,H)=n+n^3/2(n-1)H^2-n(n-2)/n(... It is proved that if M^n is an n-dimensional complete submanifold with parallel mean curvature vector and flat normal bundle in S^n+p(1), and if supM S 〈 α(n, H), where α(n,H)=n+n^3/2(n-1)H^2-n(n-2)/n(n-1)√n^2H^4+4(n-1)H^2,then M^n must be the totally urnbilical sphere S^n(1/√1+H^2).An example to show that the pinching constant α(n, H) appears optimal is given. 展开更多
关键词 SUBMANIFOLD rigidity flat normal bundle mean curvature.
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A Single Mooring System with Sag-Extensibility and Flexural Rigidity Applied to Offshore Platform 被引量:1
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作者 M.-C. Tsai Hsien Hua Lee +1 位作者 Jun-Yen Lee S.-S. Hsiao 《China Ocean Engineering》 SCIE EI CSCD 2013年第3期335-350,共16页
Floating platform system has been extensively used in ocean exploitation, particularly for a tension-leg platform (TLP) system in deep water. Most of the TLPs are multi-mooring systems, where multi-joints are connec... Floating platform system has been extensively used in ocean exploitation, particularly for a tension-leg platform (TLP) system in deep water. Most of the TLPs are multi-mooring systems, where multi-joints are connected to the tension-legs so that the platform is not allowed to twist freely and may subject to enormous force induced by large incident waves in the weak-direction of the structure. This study aims to exploit a single moored offshore platform system that may attract less force and can be operated with less effort. In our analysis, in addition to mechanical properties of the tether, two important properties are also taken into consideration for the single mooring tether with expanded cross sectional dimension and utilization of stronger material, namely, the sag-extensibility and the flexural rigidity. Finally, the dynamic structural behavior produced by the mechanical effects on the new system is investigated and compared with that of traditional design while the wave-structure interactions of large body are also accounted for. Our study finds that the neglect of sag-extensibility or the flexural rigidity of large, strong mooring cable may result in a conservative but not necessarily safe design. 展开更多
关键词 tention leg platform (TLP) single mooring platform system flexural rigidity sag extensibility wave-structure interactions
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Flexural rigidity of honeycomb consisting of hexagonal cells 被引量:3
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作者 Dai-Heng Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期840-844,共5页
In this study,the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated.It is found that the honeycomb bending can not be evaluated by using the equivalent elastic moduli obtained from... In this study,the flexural rigidity of a honeycomb consisting of regular hexagonal cells is investigated.It is found that the honeycomb bending can not be evaluated by using the equivalent elastic moduli obtained from the in-plane deformation because the moments acting on the inclined cell wall are different for in-plane deformation and bending deformation.Based on the fact that the inclined wall is twisted under the condition of the rotation angle in both connection edges being zero,a theoretical technique for calculating the flexural rigidity of honeycombs is proposed,and the validity of the present analysis is demonstrated by numerical results obtained by BFM. 展开更多
关键词 Honeycomb · Flexural rigidity · Equivalent elastic modulus · Bending · Elasticity
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On Intrinsic Rigidity for Submanifolds with Constant Scalar Curvature in Space Forms 被引量:1
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作者 陈伟 郭震 《Northeastern Mathematical Journal》 CSCD 2007年第3期200-214,共15页
Under the assumption that the normalized mean curvature vector is parallel in the normal bundle, by using the generalized ChengYau's self-adjoint differential operator, here we obtain some rigidity results for compac... Under the assumption that the normalized mean curvature vector is parallel in the normal bundle, by using the generalized ChengYau's self-adjoint differential operator, here we obtain some rigidity results for compact submanifolds with constant scalar curvature and higher codimension in the space forms. 展开更多
关键词 space form scalar curvature differential operator rigidity
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Voltage adjustment improves rigidity and tremor in Parkinson's disease patients receiving deep brain stimulation 被引量:1
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作者 Shao-hua Xu Chao Yang +11 位作者 Wen-biao Xian Jing Gu Jin-long Liu Lu-lu Jiang Jing Ye Yan-mei Liu Qi-yu Guo Yi-fan Zheng Lei Wu Wan-ru Chen Zhong pei Ling Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第2期347-352,共6页
Deep brain stimulation of the subthalamic nucleus is recognized as the most effective treatment for moderate and advanced Parkinson's disease. Programming of the stimulation parameters is important for maintaining th... Deep brain stimulation of the subthalamic nucleus is recognized as the most effective treatment for moderate and advanced Parkinson's disease. Programming of the stimulation parameters is important for maintaining the efficacy of deep brain stimulation. Voltage is consid- ered to be the most effective programming parameter. The present study is a retrospective analysis of six patients with Parkinson's disease (four men and two women, aged 37-65 years), who underwent bilateral deep brain stimulation of the subthalamic nucleus at the First Affiliated Hospital of Sun Yat-sen University, China, and who subsequently adjusted only the stimulation voltage. We evaluated motor symptom severity using the Unified Parkinson's Disease Rating Scale Part III, symptom progression using the Hoehn and Yahr scale, and the levodopa equivalent daily dose, before surgery and 1 and 2 years after surgery. The 2-year follow-up results show that rigidity and tremor improved, and clinical symptoms were reduced, while pulse width was maintained at 60 ps and frequency at 130 Hz. Voltage adjust- ment alone is particularly suitable for patients who cannot tolerate multiparameter program adjustment. Levodopa equivalent daily dose was markedly reduced 1 and 2 years after surgery compared with baseline. Our results confirm that rigidity, tremor and bradykinesia can be best alleviated by voltage adjustment. The trial was registered at ClinicalTrials.gov (identifier: NCT01934881). 展开更多
关键词 nerve regeneration deep brain stimulation Parkinson's disease subthalamic nucleus VOLTAGE pulse width frequency TREMOR rigidity BRADYKINESIA axial symptoms neural regeneration
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