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51.
We predict the possibility of observing analogue of the Aharonov-Bohm effect due to long range interaction between spins originating
in the framework of spin gauge theory developed earlier. The effect is predicted for both electrons (fermions) and photons.
Appropriate experimental set-ups are suggested. 相似文献
52.
We propose an exact branch-and-bound algorithm for the problem of maximizing the minimum machine completion time on identical
parallel machines. The proposed algorithm is based on tight lower and upper bounds as well as an effective symmetry-breaking
branching strategy. Computational results performed on a large set of randomly generated instances attest to the efficacy
of the proposed algorithm.
相似文献
53.
Mujuan Chen Jidong Liang Zhijian Zeng Xin Lin Shilong Zhang Lasheng Jiang 《Tetrahedron letters》2017,58(35):3437-3440
A new type of self-complexed bis-crown ether containing two bis(p-phenylene)-34-crown-10 (BPP34C10) ether rings and two secondary ammoniums has been synthesized and characterized. The formation of these bis-self-complexes has been identified by NMR spectroscopy, mass spectrometry and X-ray analysis. The acid/base controlled movement of these bis–crown ethers can mimic a flapping butterfly. 相似文献
54.
Vibration reduction in a flexible-link mechanism through synthesis of an optimal controller 总被引:1,自引:0,他引:1
In this paper, reduction of vibration of a flexible planar mechanism is achieved through synthesis of an optimal controller.
A finite element model, based on the equivalent rigid-link system theory, is used to accurately describe the dynamic behavior
of the system. The model, which accounts for geometric and inertial nonlinearities of the mechanism, has been fully validated
through experimental tests. In order to be able to employ the classical optimal control theory, a suitable linear model has
been derived from the original one by means of a suitable linearization procedure. Vibration reduction can then be obtained
by first defining an adequate performance index, which accounts for vibration amplitude, then by solving Riccati’s equation
in order to find the controller that minimizes the performance index, i.e. the optimal controller. The results of several
tests that have been carried out are also reported, to show the effectiveness of the synthesized control system. 相似文献
55.
STUDIES OF MELNIKOV METHOD AND TRANSVERSAL HOMOCLINIC ORBITS IN THE CIRCULAR PLANAR RESTRICTED THREE-BODY PROBLEM 总被引:1,自引:0,他引:1
STUDIES OF MELNIKOV METHOD AND TRANSVERSAL HOMOCLINIC ORBITS IN THE CIRCULAR PLANAR RESTRICTED THREE-BODY PROBLEMZhuRuzeng(朱如... 相似文献
56.
Kenneth R. Meyer 《Journal of Dynamics and Differential Equations》1991,3(3):381-397
This paper treats theN-body problem and its relation to various restricted problems. For each solution of the Kepler problem a generalization of the pulsating coordinates used to express the Hamiltonian of the elliptic restricted three-body problem is given. These coordinates are called Apollonius coordinates. The method of symplectic scaling is used to give a precise derivation of the elliptic restricted problem showing the precise asymptotic relationship between the restricted problem and the full three-body problem. This derivation obviates the proof of the fact that a nondegenerate periodic solution of the elliptic restricted three-body problem can be continued into the full three-body problem under mild nonresonance assumptions. Also, the method of symplectic scaling is used to give a precise derivation of the elliptic Hill lunar equation showing the precise relationship between the elliptic Hill lunar equation and the full three-body problem. A similar continuation theorem is established. 相似文献
57.
58.
Zoheir Ezziane 《International journal of quantum chemistry》2010,110(5):981-992
One of the grand challenges in the nanoscopic computing era is guarantees of robustness. Robust computing system design is confronted with quantum physical, probabilistic, and even biological phenomena, and guaranteeing high‐reliability is much more difficult than ever before. Scaling devices down to the level of single electron operation will bring forth new challenges due to probabilistic effects and uncertainty in guaranteeing “zero‐one” based computing. Minuscule devices imply billions of devices on a single chip, which may help mitigate the challenge of uncertainty by replication and redundancy. However, such device densities will create a design and validation nightmare with the sheer scale. The questions that confront computer engineers regarding the current status of nanocomputing material and the reliability of systems built from such minuscule devices are difficult to articulate and answer. This article illustrates and discusses two types of quantum algorithms as follows: (1) a simple quantum algorithm and (2) a quantum search algorithm. This article also presents a review of recent advances in quantum computing and intelligence and presents major achievements and obstacles for researchers in the near future. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
59.
根据分数阶线性系统的稳定理论,将混沌系统分成稳定的线性部分和相应的非线性部分.设计主动控制器,对非线性部分进行补偿,从而将分数阶混沌系统控制到平衡点.为了提高主动控制器的补偿能力,提出基于反馈的多最小二乘支持向量机(M-LS-SVM)拟合模型.通过减聚类方法将输入空间划分为一些小的局部空间,在每个局部空间中用LS-SVM建立子模型.为解决子模型相互之间的严重相关问题,提高模型的精度和鲁棒性,各个子模型的预测输出通过主元递归(PCR)方法连接.仿真实验表明该方法有助于提高补偿精度和系统响应指标.
关键词:
分数阶
混沌系统
多最小二乘支持向量机
反馈 相似文献
60.
Necessary and sufficient conditions are derived for the equalities of the best linear unbiased estimators (BLUEs) of parametric functions under a general linear model and its restricted and stochastically restricted models to hold. 相似文献