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Large-Amplitude Oscillations of Hyperelastic Cylindrical Membrane Under Thermal-Mechanical Fields

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Acta Mechanica Solida Sinica 2022年第2期35卷 303-315页

作者： wenzheng zhang Datian Niu Fengxia Zhao College of Science Dalian Minzu UniversityDalian 116600China Department of Information Engineering Qinhuangdao Vocational and Technical CollegeQinhuangdao 066100China

In this paper,the nonlinear dynamic behaviors of a hyperelastic cylindrical membrane composed of the incompressible Ogden material are examined,where the membrane is subjected to uniformly distributed radial periodic loads at the internal surface and surrounded by a thermal field.A second-order nonlinear differential equation describing the radially symmetric motion of the membrane is obtained.Then,the dynamic characteristics of the system are qualitatively analyzed in terms of different material parameter spaces and ambient tem-peratures.Particularly,for a given constant load,the bifurcation phenomenon of equilibrium points is examined.It is shown that there exists a critical load,and the phase orbits may be the asymmetrie homoclinic orbits of the“oo”type.Moreover,for the system with two centers and one saddle point,the dynamic behaviors of the system show softening phenomena at both centers,but the temperature has opposite effects on the stiffness of the structure.For a given periodically perturbed load superposed on the constant term,some complex dynamic behaviors such as quasiperiodic and chaotic oscillations are analyzed.With the Poincare section and the maximum Lyapunov characteristic exponent,it is found that the ambient temperature could lead to the irregularity and unpredictability of the nonlinear system,and also changes the threshold of chaos.

关键词： Cylindrical membrane Radial perturbed load Ambient temperature Bifurcation and chaos

A Real-time Cutting Model Based on Finite Element and Order Reduction

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Computer Systems Science & Engineering 2022年第10期43卷 1-15页

作者： Xiaorui zhang wenzheng zhang Wei Sun Hailun Wu Aiguo Song Sunil Kumar Jha Wuxi Research Institute Nanjing University of Information Science&TechnologyWuxi214100China Engineering Research Center of Digital Forensics Ministry of EducationJiangsu Engineering Center of Network MonitoringSchool of Computer and SoftwareNanjing University of Information Science&TechnologyNanjing210044China School of Automation Nanjing University of Information Science&TechnologyNanjing210044China State Key Laboratory of Bioelectronics Jiangsu Key Lab of Remote Measurement and ControlSchool of Instrument Science and EngineeringSoutheast UniversityNanjing210096China IT Fundamentals and Education Technologies Applications University of Information Technology and Management in RzeszowRzeszow Voivodeship100031Poland

Telemedicine plays an important role in Corona Virus Disease 2019(COVID-19).The virtual surgery simulation system,as a key component in telemedicine,requires to compute in real-time.Therefore,this paper proposes a realtime cutting model based on finite element and order reduction method,which improves the computational speed and ensure the real-time performance.The proposed model uses the finite element model to construct a deformation model of the virtual lung.Meanwhile,a model order reduction method combining proper orthogonal decomposition and Galerkin projection is employed to reduce the amount of deformation computation.In addition,the cutting path is formed according to the collision intersection position of the surgical instrument and the lesion area of the virtual lung.Then,the Bezier curve is adopted to draw the incision outline after the virtual lung has been cut.Finally,the simulation system is set up on the PHANTOM OMNI force haptic feedback device to realize the cutting simulation of the virtual lung.Experimental results show that the proposed model can enhance the real-time performance of telemedicine,reduce the complexity of the cutting simulation and make the incision smoother and more natural.

关键词： Virtual surgery cutting model finite element model model order reduction Bezier curve

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一种计算ARX密码差分—线性偏差的新方法

西安电子科技大学学报 2024年第2期51卷 211-223页

作者：张峰刘正斌张晶张文政保密通信重点实验室四川成都610041 中国电子科技集团公司电子科学研究院北京100041

ARX密码由模加、循环移位和异或这3种基本运算组成。目前ARX密码差分—线性区分器偏差的计算大多采用统计分析的方法。在2022年美密会上,NIU等给出了一种计算ARX密码差分—线性区分器相关度的非统计分析的方法,并给出了SPECK32/64的10... 详细信息

ARX密码由模加、循环移位和异或这3种基本运算组成。目前ARX密码差分—线性区分器偏差的计算大多采用统计分析的方法。在2022年美密会上,NIU等给出了一种计算ARX密码差分—线性区分器相关度的非统计分析的方法,并给出了SPECK32/64的10轮差分—线性区分器。基于BLONDEAU等和BAR-ON等的方法,给出了差分—线性特征的定义,并首次提出了用差分—线性特征计算差分—线性区分器偏差的方法。同时,提出了一种基于布尔可满足性问题(SAT)自动化技术搜索差分—线性特征的方法,给出了计算ARX密码差分—线性区分器偏差的非统计分析的新方法。作为应用,对NIU等给出的SPECK32/64的10轮差分—线性区分器偏差进行计算,得到的理论值为2-15.00,非常接近统计分析的实验值2-14.90,且优于NIU等给出的理论值2-16.23。同时,首次给出了SIMON32/64的9轮差分—线性区分器偏差的理论值2-8.41,接近统计分析得到的实验值2-7.12。实验结果说明了这种方法的有效性。

关键词：差分—线性区分器 ARX密码 SAT/SMT SPECK SIMON

A self-assembling prodrug nanosystem to enhance metabolic stability and anticancer activity of gemcitabine

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Chinese Chemical Letters 2022年第5期33卷 2481-2485页

作者： Mei Cong Guangling Xu Shaoyou Yang Jing zhang wenzheng zhang Dinesh Dhumal Erik Laurini Kaiyue zhang Yi Xia Sabrina Pricl Ling Peng Weidong Zhao School of Pharmacy Xinxiang Medical UniversityXinxiang 453003China Henan Key Laboratory of Immunology and Targeted Drugs School of Laboratory MedicineXinxiang Medical UniversityXinxiang 453003China Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine School of Laboratory MedicineXinxiang Medical UniversityXinxiang 453003China Aix-Marseille Université CNRSCenter Interdisciplinaire de Nanoscience de MarseilleUMR 7325Equipe Labellisépar La LigueMarseille 13288France Chongqing Key Laboratory of Natural Product Synthesis and Drug Research School of Pharmaceutical SciencesChongqing UniversityChongqing 401331China Molecular Biology and Nanotechnology Laboratory Department of Engineering and ArchitectureUniversity of TriesteTrieste 34127Italy Department of General Biophysics Faculty of Biology and Environmental ProtectionUniversity of LodzLodz 90-236Poland

Self-assembly is a powerful approach in molecular engineering for biomedical applications,in particu-lar for creating self-assembling prodrugs.Here,we report a self-assembling prodrug of the anticancer drug gemcitabine(Gem)based on amphiphilic dendrimer approach.The prodrug reported in this study demonstrates high drug loading(40%)and robust ability to self-assemble into small nanomicelles,which increase the metabolic stability of Gem and enable entry into cells via endocytosis,hence bypassing transport-mediated uptake.In addition,this prodrug nanosystem exhibited an effective pH-and enzyme-responsive release of Gem,resulting in enhanced anticancer activity and reduced toxicity.Harboring ad-vantageous features of both prodrug-and nanotechnology-based drug delivery,this self-assembling Gem prodrug nanosystem constitutes a promising anticancer candidate.This study also offers new perspectives of the amphiphilic dendrimer nanoplatforms for the development of self-assembling prodrugs.

关键词： Self-assembling prodrug Gemcitabine Amphiphilic dendrimer Anticancer candidate Nanomicelles

Identification of Secondary Dislocations by Singular Value Decomposition of the Nye Tensor

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1078-1082页

作者： Fuzhi Dai wenzheng zhang Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University

Recently, we proposed the use of singular values and singular vectors of the Nye tensor to specify the features of dislocations. To further validate the method in identifying dislocations, the algorithm is applied to detect secondary dislocations in this paper. Different from the perfect and partial dislocations where the reference state is a single crystal, the reference state for detecting secondary dislocations should be a bi-crystal in a coincident coherent state. It is demonstrated that the secondary dislocations in an interface can be correctly identified when the reference state is appropriately selected.

关键词： Nye tensor Singular value decomposition Secondary dislocation

Threshold public key encryption scheme resilient against continual leakage without random oracles

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Frontiers of Computer Science 2013年第6期7卷 955-968页

作者： Xiujie zhang Chunxiang XU wenzheng zhang Wanpeng LI School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Science and Technology on Communication Security Laboratory The 30th Research Institute of China Electronics Technology Group Corporation Chengdu 610041 China

Threshold public key encryption allows a set of servers to decrypt a ciphertext if a given threshold of authorized servers cooperate. In the setting of threshold public key encryption, we consider the question of how to correctly decrypt a ciphertext where all servers continually leak information about their secret keys to an external attacker. Dodis et al. and Akavia et al. show two concrete schemes on how to store secrets on continually leaky servers. However, their construc- tions are only interactive between two servers. To achieve continual leakage security among more than two servers, we give the first threshold public key encryption scheme against adaptively chosen ciphertext attack in the continual leak- age model under three static assumptions. In our model, the servers update their keys individually and asynchronously, without any communication between two servers. Moreover, the update procedure is re-randomized and the randomness can leak as well.

关键词： leakage-resilient continual leakage Threshold Public Key Encryption adaptive chosen ciphertext security standard model

Dislocation-mediated migration of interphase boundaries

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Journal of Materials Science & Technology 2019年第11期35卷 2714-2726页

作者： Zhipeng Sun Fuzhi Dai Ben Xu wenzheng zhang School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China Key Laboratory of Advanced Materials(MOE) State Key Laboratory of New Ceramics and Fine ProcessingChina

Faceted interphase boundaries(IPBs)are commonly observed in lath-shaped precipitates in alloys consisting of simple face-centred cubic(fcc),body centred-cubic(bcc)or hexagonal closed packed(hcp)phases,which normally contain one or two sets of parallel dislocations.The influence of these dislocations on interface migration and possible accompanying long-range strain field remain unclear.To elucidate this,we carried out atomistic simulations to investigate the dislocation-mediated migration processes of IPBs in a pure-iron system.Our results show that the migration of these IPBs is accompanied with the slip of interfacial dislocations,even in high-index slip planes,with two migration modes were observed:the first mode is the uniform migration mode that occurs only when all of the dislocations slip in a common slip plane.A shear-coupled interface migration was observed for this mode.The other interfaces propagate in the stick-slip migration mode that occurs when the dislocations glide on different slip planes,involving dislocation reaction or tangling.A quantitative relationship was established to link the atomic displacements with the dislocation structure,slip plane,and interface normal.The macroscopic shear deformation due to the effect of overall atomic displacement shows a good agreement with the results obtained based on the phenomenological theory of martensite crystallography.Our findings have general implications for the understanding of phase transformations and the surface relief effect at the atomic scale.

关键词： Interphase boundary migration O-line interface Shear-coupled interface migration Dislocation gliding Atomic displacement

FINITE DEFORMATION OF A CLASS OF RECTANGULAR RUBBER RINGS SUBJECTED TO END AXIAL LOADS

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Acta Mechanica Solida Sinica 2012年第2期25卷 144-151页

作者： wenzheng zhang Xuegang Yuan Hongwu zhang Jiusheng Ren State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsFaculty of Vehicle Engineering and MechanicDalian University of TechnologyDalian 116024China School of Science Dalian National UniversityDalian 116600China Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China

The problem of finite deformation of an incompressible rectangular rubber ring with an internal rigid body, where the ring is subjected to equal axial loads at its two ends, is examined. A reasonable mathematical model is formulated by using the nonlinear field theory and the implicit analytical solutions are derived. Then numerical simulations are implemented to further illustrate the results and obtain some meaningful conclusions. The deformation of the lateral surface of the ring becomes larger with the increasing axial loads, the decreasing ratio of the inner and outer radii and the increasing height of the ring.

关键词： neo-Hookean material rectangular rubber ring axial load finite deformation implicit analytical solution

New forward-secure signature schemes with untrusted update

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Frontiers of Computer Science 2013年第4期7卷 536-543页

作者： Wanpeng LI Chunxiang XU wenzheng zhang Shixiong ZHU Xiujie zhang School of Computer Science and Engineering University of Electronic Science and Technology of China Chengdu 611731 China Science and Technology on Communication Security Laboratory The 30th Research Institute of China Electronics Technology Group Corporation Chengdu 610041 China

In this paper, we present two forward-secure signature schemes （FSS） with untrusted update. Our constructions use ideas from the work of Abdalla et al. [1] and Kozlov and Reyzin [2] in their forward-secure digital signature schemes. Our schemes are proven to be forward-secure based on the hardness of factoring in the random oracle model. Both schemes use the same method to encrypt the private key and are more efficient than Libert scheme [3] without adding any burden to the original forward-secure schemes.

关键词： forward-secure digital signature untrusted update