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1.
State change, quantum probability, and information gain in the operational phasespace measurement are formulated by means of positive operator-valued measure (POVM) and operation. The properties of the operational POVM and its marginal POVM which yield the quantum probability distributions of the measurement outcomes obtained by the operational phase-space measurement are investigated. The Naimark extension of the operational POVM can be expressed in terms of the relative-position states and the relative-momentum states in the extended Hilbert space. An observable quantity measured in the operational phase-space measurement becomes a fuzzy or unsharp observable. The state change of a physical system caused by the operational phase-space measurement is described by the operation which is obtained explicitly for the position and momentum measurements and for the simultaneous measurement of position and momentum. Using the results, the entropy change of the measured physical system and the information gain in the operational phase-space measurement are investigated. It is found that the average value of the entropy change is equal to the Shannon mutual information extracted from the outcomes exhibited by the measurement apparatus.  相似文献   

2.
The general expression with the physical significance and positive-definite condition of the eigenvalues of 4×4 Hermitian and trace-one matrix are obtained. The obvious expression of Peres' separability condition for an arbitrary state of two qubits is then given and its operational feature is enhanced. Furthermore, we discuss some applications to the calculation of the entanglement, the upper bound of the entanglement, and a model of the transfer of entanglement in a qubit chain with noise.  相似文献   

3.
P V Bhagwat 《Pramana》2002,59(5):719-724
14 UD Pelletron Accelerator Facility at Mumbai has been operational since 1989. The project MEHIA (medium energy heavy ion accelerator) started in 1982 and was formally inaugurated on 30th December 1988. Since then the accelerator has been working round the clock. Improvement in accelerator performance and operational experience are described.  相似文献   

4.
Billiard systems within quadrics, playing the role of discrete analogues of geodesics on ellipsoids, are incorporated into the theory of integrable quad-graphs. An initial observation is that the Six-pointed star theorem, as the operational consistency for the billiard algebra, is equivalent to an integrability condition of a line congruence. A new notion of the double reflection nets as a subclass of dual Darboux nets associated with pencils of quadrics is introduced, basic properties and several examples are presented. Corresponding Yang–Baxter maps, associated with pencils of quadrics are defined and discussed.  相似文献   

5.
A generalized Noether's theorem and the operational determination of a physical geometry in quantum physics are used to motivate a quantum geometry consisting of relations between quantum states that are defined by a universal group. Making these relations dynamical implies the nonlocal effect of the fundamental interactions on the wave function, as in the Aharonov–Bohm effect and its generalizations to non-Abelian gauge fields and gravity. The usual space–time geometry is obtained as the classical limit of this quantum geometry using the quantum-state space metric.  相似文献   

6.
7.
利用挤出胀大动力学理论研究稳态剪切流下HDPE 和PBD液体的挤出胀大行为,建立了自由动态下线团回复和挤出胀大增长时间的回复机制和动力学. 结果表明在自由回复过程中自由线团回复和挤出物胀大增长可分为两个区域(瞬间和推迟区)、三个增长阶段(瞬间、推迟和最终阶段). 证明了自由线团回复和挤出胀大增长可表征为增长时间、剪切应力和长径比的函数。从而从动力学理论推倒出了三种挤出胀大效应(瞬间、推迟和最终)同分子结果参数和挤出操作条件间的相关性. 并建立了总合(TESE)和最终(UESE)两组挤出胀大效应的普适方程.  相似文献   

8.
阙渭焰 《强激光与粒子束》2018,30(4):043201-1-043201-7
围绕战场电磁作战环境智能表征问题,首先从认知这一概念切入,去理解作战艺术与认知作战的关系,并将电磁域作战与电磁频谱作战、电磁频谱作战与陆、海、空、天、网络联合作战紧密联系在一起;进而通过认知科学与人工智能视角,厘清了联指三类作战态势图构建与运作对电磁目标和战场电磁环境要素和表征的要求;针对电磁域作战全过程各任务阶段各层级人员认知水平,分析了战场电磁作战环境的分层认知与智能表征的内涵与关系,并对战场电磁作战环境智能表征问题在宏观上进行了把握。  相似文献   

9.
QCD and Spin physics are playing important role in our understanding of hadron structure. I will give a short overview of origin of hadron structure in QCD and highlight modern understanding of the subject. Jefferson Laboratory is undergoing an upgrade that will increase the energy of electron beam up to 12 GeV. JLab is one of the leading facilities in nuclear physics studies and once operational in 2015 JLab 12 will be crucial for future of nuclear physics. I will briefly discuss future studies in four experimental halls of Jefferson Lab.  相似文献   

10.
Over the past two decades, observational studies using aircraft and satellite data to supplement conventional surface and upper air data have revealed much about the structure of tropical cyclones. During this same period, numerical weather prediction models have been developed to study the dynamics and energetics of these intense, destructive storms. This article reviews the structure of mature tropical cyclones and discusses the physical processes that are important in their genesis and maintenance. Some examples of computer simulation models are presented. Finally, the operational prediction of actual tropical storms by statistical and dynamical methods is summarized.  相似文献   

11.
The concept of steering was introduced by Schr?dinger in 1935 as a generalization of the Einstein-Podolsky-Rosen paradox for arbitrary pure bipartite entangled states and arbitrary measurements by one party. Until now, it has never been rigorously defined, so it has not been known (for example) what mixed states are steerable (that is, can be used to exhibit steering). We provide an operational definition, from which we prove (by considering Werner states and isotropic states) that steerable states are a strict subset of the entangled states, and a strict superset of the states that can exhibit Bell nonlocality. For arbitrary bipartite Gaussian states we derive a linear matrix inequality that decides the question of steerability via Gaussian measurements, and we relate this to the original Einstein-Podolsky-Rosen paradox.  相似文献   

12.
为探讨分析转镜运转可靠性的数值方法,运用Monte Carlo理论并结合ANSYS参量化设计语言,根据小样本原理和可靠性理论建立了转镜运转可靠性分析数学模型.对转镜运转可靠性进行了数值分析,并对数值分析结果进行了实验验证.数值分析结果表明:转镜的功能函数值远大于零,最大应力与转镜转速的线性相关系数达0.9,镜体密度的相关系数值为0.15,最大应力、应变、位移的偏斜度和峭度值均为正值,统计结果服从正态分布呈右偏态,在95%的置信度水平下,转镜可靠度为0.999.这说明在理想状态下转镜的运转可靠性满足要求,转镜的最大应力值取决于转镜转速,并且镜体的密度对转镜最大应力有较大影响.转镜运转可靠性试验中没有转镜出现破坏,表明转镜运转可靠性数值分析方法是正确的,为转镜的运转可靠性分析提供一种可行、高效的数值分析手段.  相似文献   

13.
Some classical and quantum theories are characterized within the convexity approach to probabilistic physical theories. In particular, the structure of the so-called DHB quantum theory will be analyzed. It turns out that the natural generalization of the standard Hubert space quantum mechanics, the operational one, is such a theory. The operational Hilbert space quantum theory will be reconstructed from the (weak) projection postulate and the complementarity principle. This is then used to argue that the DHB quantum theory is identical with the operational Hilbert space quantum theory.  相似文献   

14.
针对联合作战中光电对抗系统作战效能评估问题,用联合指数法对联合作战中光电对抗系统中的单件光电对抗装备、光电对抗平台、光电对抗基本作战单位的作战能力进行了量化,对系统作战能力标量指数进行了聚合,并对光电对抗系统基本编组和光电对抗系统的作战能力进行了量化分析,最后用指数一兰彻斯特方程对光电对抗系统的作战效能进行了评估,其结果可为评判联合作战行动方案的完成情况提供参考。  相似文献   

15.
张月荣  袁晓 《物理学报》2021,(4):349-359
标度拓展经典负半阶分抗逼近电路,可实现具有任意分数阶微积算子运算功能的分抗逼近电路,但牺牲了运算恒定性.从电路网络的角度分析具有恒定运算性能的负半阶Carlson分形格分抗逼近电路.根据标度分形格分抗逼近电路的等效无源双口网络,探讨该双口网络右侧端口的运算有效性,设计具有高运算恒定性的任意阶标度分形格分抗逼近电路.结合...  相似文献   

16.
The dynamical core, which governs the evolution of resolved fluid-dynamical processes, is a critical element of any atmospheric model. Its governing equations must include all relevant dynamical terms, and the numerical formulae used to approximate them must be accurate, stable and efficient. This is particularly so in a unified modeling environment in which the same dynamical core is used for both operational weather prediction and long term climate simulations.Recent research at the Met Office on unified dynamical core issues is reviewed. Aspects covered include: properties of various equation sets; vertical coordinates; semi-Lagrangian advection and conservation; trajectory computation and dynamical equivalence; horizontal and vertical discretization; and coupling of physical parameterizations to a dynamical core.  相似文献   

17.
An overview is given of recent activities at the NIST electron beam ion trap (EBIT) facility. The machine has been operational for almost three years. Important characteristics and demonstrated capabilities of our EBIT are presented. Selected results include experiments with trapped highly charged ions (X-ray and visible spectroscopy), and with extracted ions (ion-surface collision studies). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
An enhanced metamaterial absorber based on the circumscribed-cross resonator is introduced in this paper. The new structure is polarization-independent, due to the symmetry of its unit cell, and is proven efficient for the attenuation of obliquely incident waves. The absorption mechanism is thoroughly investigated and is found to be mainly related to the losses of the dielectric substrate. Furthermore, by exploiting the scalability property of metamaterials, the operational bandwidth of our design can be drastically improved by placing unit cells with properly scaled resonators adjacent to each other. In this context, various combinations of three, four, and nine unit cells that can increase the full width at half maximum up to as much as 11.18?%, are developed. The overall performance of the proposed configurations is deemed promising for the realization of microwave metamaterial absorbers for several practical applications.  相似文献   

19.
MCP最佳运转参数选择的讨论   总被引:1,自引:1,他引:0  
汪金祥 《光子学报》1991,20(3):288-291
本文给出了选择MCP最佳运转参数的正确判据。论证了以前Schagen给出的表达式只是一种在给定工作电压下确定MCP最佳长径比的判据。讨论了MCP在两种极值状态下运转的特性和适应性。  相似文献   

20.
何秋燕  余波  袁晓 《中国物理 B》2017,26(4):40202-040202
The performance analysis of the generalized Carlson iterating process,which can realize the rational approximation of fractional operator with arbitrary order,is presented in this paper.The reasons why the generalized Carlson iterating function possesses more excellent properties such as self-similarity and exponential symmetry are also explained.K-index,P-index,O-index,and complexity index are introduced to contribute to performance analysis.Considering nine different operational orders and choosing an appropriate rational initial impedance for a certain operational order,these rational approximation impedance functions calculated by the iterating function meet computational rationality,positive reality,and operational validity.Then they are capable of having the operational performance of fractional operators and being physical realization.The approximation performance of the impedance function to the ideal fractional operator and the circuit network complexity are also exhibited.  相似文献   

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