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1.
In this paper,we show that for any given planar cubic algebraic curves defined by a quadratic Hamiltonian vector field,we can always have their exact explicit parametric representations. We use a model of micro-structured solid to show an application of our conclusions.  相似文献   

2.
Recently, a new type of Radio Frequency IDentification (RFID) system with mobile readers is introduced. In such a system, it is more desirable for mobile readers to identify tags without a back-end server, and thus it is frequently referred as a serverless mobile RFID system. In this paper, we formalize a serverless mobile RFID system model and propose a new encryption-based system that preserves the privacy of both tags and readers in the model. In addition, we define a new adversary model for the system model and show the security of the proposed system. Throughout comparisons between ours and the other alternatives, we show that our proposed system provides a stronger reader privacy and robustness against a reader forgery attack than the competitors.  相似文献   

3.
We study the dynamics of two entangled atoms interacting with a common structured reservoir. By means of the exact solution of atomic dynamics, we show a novel quantum interference controlled by the relative phase of initial entangled state of the atoms. The quantum interference has a great influence on trapped excited-state population and stationary entanglement of the atoms. In particular, we construct an explicit condition under which atomic stationary entanglement can grow over their initial value.  相似文献   

4.
This paper proposes an efficient framework to utilize quantum search practically.To the best of our knowledge,this is the first paper to show a concrete usage of quantum search in general programming.In our framework,we can utilize a quantum computer as a coprocessor to speed-up some parts of a program that runs on a classical computer.To do so,we propose several new ideas and techniques,such as a practical method to design a large quantum circuits for search problems and an efficient quantum comparator.  相似文献   

5.
In this paper we survey the geometric method in quantum control.By presenting a geometric representation of nonlocal two-qubit quantum operation,we show that the control of two-qubit quantum operations can be reduced to a steering problem in a tetrahedron.Two physical examples are given to illustrate this method.We also provide analytic approaches to construct universal quantum circuit from any arbitrary quantum gate.  相似文献   

6.
In this paper, we study the dimension estimate of global attractor for a 3D Brinkman-Forchheimer equation. Based on the differentiability of the semigroup with respect to the initial data, we show that the global attractor of strong solution of the 3D BrinkmanForchheimer equation has finite Hausdorff and fractal dimensions.  相似文献   

7.
HB-MAP (HB-mutual authentication protocol) is a mutual ultra-light-weight authentication protocol we have proposed before. In this paper, we present an HB-MAP simulation model. This model is based on the OPNET modeler and includes three parts, namely, the network model, the node model, and the process model. The simulation results are obtained mainly in the aspects of running time, queuing delay, throughput, and channel utilization. To show the performance of HB-MAP, simulation of two other protocols HB and LCAP (load-based concurrent access protocol) is also executed, and comparative analysis is carried out on the results. At the end of the paper, we show a simple process of the attacks and identify that the HB-MAP can defend against some attacks.  相似文献   

8.
In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this paper, we present a general security model for ID-based proxy multi-signature (ID-PMS) schemes. Then, we show how to construct a secure ID-PMS scheme from a secure ID-based signature scheme, and prove that the security of the construction can be reduced to the security of the original ID-based signature scheme.  相似文献   

9.
In this paper, we improve the trawling and point out some communities missed by trawling. We use the DBG (Dense Bipartite Graph) to identify a structure of a potential community instead of CBG (Complete Bipartite Graph). Based on DBG, we proposed a new method based on edge removal to extract cores from a web graph. Moreover, we improve the crawler to save only potential pages as fans of a core and save a lot of disk storage space. To evaluate the set of cores whether or not belong to a community, the statistics of term frequency is used. In the paper, the dataset of experiment were crawled under domain ".cn". The result show that the our algorithm works properly and some new cores can be found by our method.  相似文献   

10.
On the basis of software testing tools we developed for progrmnming languages, we firstly present a new control flowgraph model based on block. In view of the notion of block, we extend the traditional program-based software test data adequacy measurement criteria, and empirically analyze the subsume relation between these measurement criteria. Then, we define four test complexity metrics based on block. They are J-complexity 0; J-complexity 1 ; J-complexity 1 ; J-complexity 2. Finally, we show the Kiviat diagram that makes software quality visible.  相似文献   

11.
In traditional view,atomic packing is random in glasses made of metallic elements with non-directional interactions as the glass-forming liquid needs to be excited to remain in liquid state before being cooled sufficiently fast to a glass. Locally ordered packing however is possible if certain conditions are favorable,such as a strong bonding between elements,or low configuration energy of a cluster of atoms as suggested by Frank. In alloy systems made of different metallic elements,we show that Frank’s criterion alone does not necessarily lead to certain specific local ordered packing or cluster formation such as icosahedral packing. In this context,we revisit the issue of atomic packing and cluster formation,and show that an alloy system with fairly random liquid configuration could be sufficient to produce a variety of noticeable locally ordered packing with low energy,albeit largely statistical in nature. Therefore,we emphasize the importance of the system parameters such as the atomic size,alloy concentration,and interaction potential in their collective contribution to local atomic packing.  相似文献   

12.
In determining the replenishment policy for an inventory system, some researchers advocated that the iterative method of Newton could be applied to the derivative of the total cost function in order to get the optimal solution. But this approach requires calculation of the second derivative of the function. Avoiding this complex computation we use another iterative method presented by the second author. One of the goals of this paper is to present a unified convergence theory of this method. Then we give a numerical example to show the application of our theory.  相似文献   

13.
LEACH (Low-Energy Adaptive Clustering Hierarchy) protocol is a basic clustering-based routing protocol of sensor networks. In this paper, we present the design of SLEACH, a secure extension for the LEACH protocol. We divide SLEACH into four phases and fit inexpensive cryptographic operations to each part of the protocol functionality to create an efficient, practical protocol. Then we give security analyses of SLEACH. Our security analyses show that our scheme is robust against any external attacker or compromised nodes in the sensor network  相似文献   

14.
This paper introduces a new method of measuring the three-dimensional drape shape of fabrics with structural light. First, we apply parallel annular structural light to form light and shade alternating contour stripes on the surface of fabrics. We then collect the images of contour stripes using Charge Coupled Device (CCD). Subsequently, we process the images to identify the contour stripes and edges of fabrics, and obtain the fabric contour lines of curved surfaces. Finally, we apply three-dimensional curved surface modeling method based on a network of polar coordinates, and reconstruct the three-dimensional drape shape of fabrics. Experiments show that our method is effective in testing and reconstructing three-dimensional drape shape of fabrics.  相似文献   

15.
In this paper we propose four-dimensional (4D) operators,which can be used to deal with sequential changes of topological relationships between 4D moving objects and we call them 4D development operators. In contrast to the existing operators,we can apply the operators to real applications on 4D moving objects. We also propose a new approach to define them. The approach is based on a dimension-separated method,which considers x-y coordinates and ( coordinates separately. In order to show the applicability of our operators,we show the algorithms for the proposed operators and development graph between 4D moving objects.  相似文献   

16.
We introduce the concept of T-fuzzy subhypermodules of hypermodules with respect to triangular norms and obtain some results. In particular, we define a probabilistic version of hypermodules using random sets and show that fuzzy hypermodules defined in triangular norms are consequences of probabilistic hypermodules under certain conditions.  相似文献   

17.
Jajcay‘s studies( 1993 ; 1994) on the automorphism groups of Cayley maps yielded a new product of groups, which he called, rotary product. Using this product, we define a hyperoperation ⊙ on the group Syme (G) , the stabilizer of the identity e ∈ G in the group Sym (G) . We prove that ( Syme (G) , ⊙) is a hypergroup and characterize the subhypergroups of this hypergroup.Finally, we show that the set of all subhypergroups of Syme ( G ) constitute a lattice under ordinary join and meet and that the minimal elements of order two of this lattice is a subgroup of Aut (G) .  相似文献   

18.
Based on building footprints (building polygons) on digital maps, we are proposing the GIS and CG integrated system that automatically generates 3D building models with multiple roofs. Most building polygons’ edges meet at right angles (orthogonal polygon). The integrated system partitions orthogonal building polygons into a set of rectangles and places rectangular roofs and box-shaped building bodies on these rectangles. In order to partition an orthogonal polygon, we proposed a useful polygon expression in deciding from which vertex a dividing line is drawn. In this paper, we propose a new scheme for partitioning building polygons and show the process of creating 3D roof models.  相似文献   

19.
Subjective logic provides a means to describe the trust relationship of the real world.However,existing fusion operations it offers treat fused opinions equally,which makes it impossible to deal with the weighted opinions effectively.A.Jφsang presents a solution,which combines the discounting operator and the fusion operator to produce the consensus to the problem.In this paper,we prove that this approach is unsuitable to deal with the weighted opinions because it increases the uncertainty of the consensus.To address the problem,we propose two novel fusion operators that are capable of fusing opinions according to the weight of opinion in a fair way,and one of the strengths of them is improving the trust expressiveness of subjective logic.Furthermore,we present the justification on their definitions with the mapping between the evidence space and the opinion space.Comparisons between existing operators and the ones we proposed show the effectiveness of our new fusion operations.  相似文献   

20.
In this paper,we will give a very simpleproof of a conjecture of Graffiti. (WOW Conjecture 584) :Let T be a tree of order n with independence number a , thenA λ1≤ 2 + a , where A t is the Laplacian spectralradius. ( Xiao - dong Zhang , On the two conjectures of Graffiti, Linear Algebra and its Applications , described all extremal treesthat attain the maximal Laplacian spectral radius and used theresults to show conjectures.  相似文献   

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