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Ab Initio Molecular-Dynamics Simulation Liquid and Amorphous Al<sub>94-x</sub>Ni<sub>6</sub>La<sub>x</sub> (x=3-9) Alloys
No full textAb initio molecular-dynamics simulations have been used to investigate the liquid and amorphous Al94-xNi6Lax (x=3-9) alloys. Through calculating the pair distribution functions and partial coordination numbers, the structure and properties of these alloys are researched, which will help the design bulk metallic glass. The concentration of La atoms can affect the short-range order of Al94-xNi6Lax alloys, which is also studied in this calculation result
Sentiment Analysis Method Based on Kmeans and Online Transfer Learning
Get PDFSentiment analysis is a research hot spot in the field of natural language processing and content security. Traditional methods are often difficult to handle the problems of large difference in sample distribution and the data in the target domain is transmitted in a streaming fashion. This paper proposes a sentiment analysis method based on Kmeans and online transfer learning in the view of fact that most existing sentiment analysis methods are based on transfer learning and offline transfer learning. We first use the Kmeans clustering algorithm to process data from one or multiple source domains and select the data similar to target domain data to establish the classifier, so that the processed data does not negatively transfer the data in the target domain. And then create a new classifier based on the new target domain. The source domain classifier and target domain classifier are combined with certain weights by using the homogeneous online transfer learning method to achieve sentiment analysis. The experimental results show that this method has achieved better performance in terms of error rate and classification accuracy
Privacy-Preserving Quantum Two-Party Geometric Intersection
Get PDFPrivacy-preserving computational geometry is the research area on the intersection of the domains of secure multi-party computation (SMC) and computational geometry. As an important field, the privacy-preserving geometric intersection (PGI) problem is when each of the multiple parties has a private geometric graph and seeks to determine whether their graphs intersect or not without revealing their private information. In this study, through representing Alice’s (Bob’s) private geometric graph GA (GB) as the set of numbered grids SA (SB), an efficient privacy-preserving quantum two-party geometric intersection (PQGI) protocol is proposed. In the protocol, the oracle operation OA (OB) is firstly utilized to encode the private elements of SA =(a0,a1,…,aM-1) (SB =(b0,b1,…,bN-1)) into the quantum states, and then the oracle operation Of is applied to obtain a new quantum state which includes the XOR results between each element of SA and SB. Finally, the quantum counting is introduced to get the amount (t) of the states |ai⊕bj| equaling to |0|, and the intersection result can be obtained by judging t >0 or not. Compared with classical PGI protocols, our proposed protocol not only has higher security, but also holds lower communication complexity
An Integrated Suture Simulation System with Deformation Constraint Under A Suture Control Strategy
Get PDFCurrent research on suture simulation mainly focus on the construction of suture line, and existing suture simulation systems still need to be improved in terms of diversity, soft tissue effects, and stability. This paper presents an integrated liver suture surgery system composed of three consecutive suture circumstances, which is conducive to liver suture surgery training. The physically-based models used in this simulation are based on different mass-spring models regulated by a special constrained algorithm, which can improve the model accuracy, and stability by appropriately restraining the activity sphere of the surrounding mass nodes around the suture points. We also studied the kinematic model to update the status of suture points in real time, according to an external force exerted by the operators, which can sense synchronous force feedback in return as well. Moreover, in case that the sutured wounds tear open again, a suture control strategy is designed to ensure the stability of the whole suturing procedure. Several experiments are carried out to validate the model performance in terms of model accuracy, suture control effects, and comprehensive training effects. The experiment results show that the proposed models have realistic visual and haptic feedback, stable control on the suture, as well as good training effects as an integrated liver suture surgery system compared to other suture simulation systems which only simulate suture on a single kind of soft tissue
A Chain Approach of Boundary Element Row-Subdomains for Simulating the Failure Processes in Heterogeneous Brittle Materials
Get PDFTo improve the effectiveness of the lattice model for simulating the failure processes of heterogeneous brittle materials, each lattice element is refined as a subdomain with homogenous material, and is modeled by the boundary element method in this paper. For simplicity, each subdomain is modeled with constant boundary elements. To enhance the efficiency, a row of sub-domains is formed, and then a chain structure of such row-subdomain is constructed. The row-equation systems are solved one by one, and then back substituted, to obtain the final solution. Such a chain subdomain approach of the boundary element method not only reduces the operations, but also the memory requirements. By ``failure'' of the heterogeneous brittle material is meant to be the debonding of the interface of subdomains, and each homogeneous subdomain remains to be linear elastic. For the simulation of the failure process, a quasi-static approach is adopted. The criterion of interface strength is used to determine the element wherein the interface debonding will occur, and then the interface continuity condition is replaced by the interface debonding condition for the next computation. The simulation of the failure process is controlled by the sequential debonding of the boundary elements. Some results are given to show the applicability of the presented BEM scheme, and the complexity of the failure process of heterogeneous material
A Discrete Fourier Transform Framework for Localization Relations
Get PDFLocalization relations arise naturally in the formulation of multi-scale models. They facilitate statistical analysis of local phenomena that may contribute to failure related properties. The computational burden of dealing with such relations is high and recent work has focused on spectral methods to provide more efficient models. Issues with the inherent integrations in the framework have led to a tendency towards calibration-based approaches. In this paper a discrete Fourier transform framework is introduced, leading to an extremely efficient basis for the localization relations. Previous issues with the Green's function integrals are resolved, and the method is validated against finite element analysis
Numerical Simulation of Double Diffusive Mixed Convection in a Horizontal Annulus with Finned Inner Cylinder
Get PDFThe present work relates to a numerical investigation of double diffusive mixed convection around a horizontal annulus with a finned inner cylinder. The solutal and thermal buoyancy forces are sustained by maintaining the inner and outer cylinders at uniform temperatures and concentrations. Buoyancy effects are also considered, with the Boussinesq approximation. The forced convection effect is induced by the outer cylinder rotating with an angular velocity (ω) in an anti-clockwise direction. The studies are made for various combinations of dimensionless numbers; buoyancy ratio number (N), Lewis number (Le), Richardson number (Ri) and Grashof number (Gr). The isotherms, isoconcentrations and streamlines as well as both average and local Nusselt and Sherwood numbers were studied. A finite volume scheme is adopted to solve the transport equations for continuity, momentum, energy and mass transfer. The results indicate that the use of fins on the inner cylinder with outer cylinder rotation, significantly improves the heat and mass transfer in the annulus
Computation of the time-dependent Green's function of three dimensional elastodynamics in 3D quasicrystals
No full textThe time-dependent differential equations of elasticity for 3D quasicrystals are considered in the paper. These equations are written in the form of a vector partial differential equation of the second order with symmetric matrix coefficients. The Green's function is defined for this vector partial differential equation. A new method of the numerical computation of values of the Green's function is proposed. This method is based on the Fourier transformation and some matrix computations. Computational experiments confirm the robustness of our method for the computation of the time-dependent Green's function in icosahedral quasicrystals
Applications of Parameter-Expanding Method to Nonlinear Oscillators in which the Restoring Force is Inversely Proportional to the Dependent Variable or in Form of Rational Function of Dependent Variable
No full textHe's parameter-expanding method with an adjustment of restoring forces in terms of Chebyshev's series is used to construct approximate frequency-amplitude relations for a conservative nonlinear singular oscillator in which the restoring force is inversely proportional to the dependent variable or in form of rational function of dependant variable. The procedure is used to solve the nonlinear differential equation approximately. The approximate frequency obtained using this procedure is more accurate than those obtained using other approximate methods and the discrepancy between the approximate frequency and the exact one negligible
Strong Solutions of the Fuzzy Linear Systems
No full textWe consider a fuzzy linear system with crisp coefficient matrix and with an arbitrary fuzzy number in parametric form on the right-hand side. It is known that the well-known existence and uniqueness theorem of a strong fuzzy solution is equivalent to the following: The coefficient matrix is the product of a permutation matrix and a diagonal matrix. This means that this theorem can be applicable only for a special form of linear systems, namely, only when the system consists of equations, each of which has exactly one variable. We prove an existence and uniqueness theorem, which can be use on more general systems. The necessary and sufficient conditions of the theorem are dependent on both the coefficient matrix and the right-hand side. This theorem is a generalization of the well-known existence and uniqueness theorem for the strong solution