Deterministic joint remote preparation of an arbitrary two-qubit state in the presence of noise

Using two tripartite Greenberger-Horne-Zeilinger （GHZ） states as the shared channels, we investigate the noise effects on the deterministic joint remote preparation of an arbitrary two-qubit state. By unitary matrix decomposition procedure, we first construct the quantum logic circuit of the deterministic joint remote state preparation protocol. Then, we analytically derive the fidelity and the average fidelity for the deterministic joint remote preparation of an arbitrary two- qubit state and of four types of special two-qubit states under the influence of the Pauli noises. It is found that the fidelity depends on the noise types, the qubit-environment coupling strength, and the state to be remotely prepared. Moreover, even if the two GHZ channels are subject to the same environmental noises, the average fidelities for remotely preparing different two-qubit states display different time evolution behaviors. The remote preparation of the identical two-qubit states also shows that the average fidelities affected by different noisy environments exhibit different evolution actions.

Deterministic joint remote state preparation of arbitrary two-and three-qubit states

We propose a novel deterministic protocol that two senders are capable of remotely preparing arbitrary two-and three-qubit states for a remote receiver using EPR pairs and GHZ state as the quantum channel.Compared with the existing deterministic protocols [An et al.2011 Phys.Lett.A 375 3570 and Chen et al.2012 J.Phys.A：Math.Theor.45 055303],the quantum resources and classical information in our scheme are decreased,and the whole operation process is simplified.

Joint remote preparation of an arbitrary five-qubit Brown state via non-maximally entangled channels

We firstly present a novel scheme for deterministic joint remote state preparation of an arbitrary five-qubit Brown state using four Greenberg-Horme-Zeilinger （GHZ） entangled states as the quantum channel. The success probability of this scheme is up to 1, which is superior to the existing ones. Moreover, the scheme is extended to the generalized case where three-qubit and four-qubit non-maximally entangled states are taken as the quantum channel. We simultaneously employ two common methods to reconstruct the desired state. By comparing these two methods, we draw a conclusion that the first is superior to the second-optimal positive operator-valued measure only taking into account the number of auxiliary particles and the success probability.

Deterministic joint remote state preparation of arbitrary single- and two-qubit states

In this paper, two novel schemes for deterministic joint remote state preparation（JRSP） of arbitrary single- and twoqubit states are proposed. A set of ingenious four-particle partially entangled states are constructed to serve as the quantum channels. In our schemes, two senders and one receiver are involved. Participants collaborate with each other and perform projective measurements on their own particles under an elaborate measurement basis. Based on their measurement results,the receiver can reestablish the target state by means of appropriate local unitary operations deterministically. Unit success probability can be achieved independent of the channel＇s entanglement degree.

Deterministic hierarchical joint remote state preparation with six-particle partially entangled state

In this paper, we present a novel scheme for hierarchical joint remote state preparation（HJRSP） in a deterministic manner, where two senders can jointly and remotely prepare an arbitrary single-qubit at three receivers＇ port. A six-particle partially entangled state is pre-shared as the quantum channel. There is a hierarchy among the receivers concerning their powers to reconstruct the target state. Due to various unitary operations and projective measurements, the unit success probability can always be achieved irrespective of the parameters of the pre-shared partially entangled state.

Spin-Split Joint Density of States in GdN

We present an investigation of the optical constants of the near stoichiometric GdN films. Transmission and reflection spectra are collected for the paramagnetic and the ferromagnetic GdN in the photon energy range of 0.5-5.5 eV. In the ferromagnetic phase, behaviors of minority and majority spin states are specifically focussed on, which indicate spin-split joint density of states. The results confirm the LSDA＋U estimates of energy gap associated with the majority-spins and also the magnitude of spin splitting.

Sliding state stepping algorithm for solving impact problems of multi-rigid-body system with joint friction

Impact dynamics of multi-rigid-body systems with joint friction is considered. Based on the traditional approximate assumption dealing with impact problem, a general numerical method called the sliding state stepping algorithm is introduced. This method can avoid difficulties in solving differential equations with variable scale and its result can avoid energy inconsistency before and after impact from considering complexily of tangential sliding mode. An example is given to describe details using this algorithm.

Finite-Element Analysis of Parts Stress State of Tight Joint Assembled by Press Fitting

This paper includes descriptions of the stress distribution regularities in the tight joint parts, regularities of the stress state changes in the contact region along coupling length, stress concentration factors, levels of additional stresses caused by press fitting. Distributions of stress intensity, axial stress, contact pressure, tangent stress in parts and in contact zone along coupling length are considered. Calculation results obtained by three approaches: Lame relationships, FEM without considering assembly method, FEM with considering press fitting process are analyzed and compared. The adequacy of research carried out is confirmed.

Relevant State Agencies Will Conduct a Joint Annual Inspection on Foreign Invested Enterprises

The Ministry of Foreign Trade and Economic Coop-eration (MOFTEC),the State Administration forIndustry and Commerce (SAIC),the State Economicand Trade Commission (SETC),the Ministry of Finance(MOF),the State Administration for Exchange Control(SAEC),the State Taxation Bureau (STB) and the GeneralCustoms Administration (GCA) (hereinafter referred to asCompetent Joint Annual Inspection Agencies) have jointlyissued a circular a few days before which stipulates that,from the year 1997 onwards,a joint annual inspection willbe conducted on FIEs in order to further improve and stan-dardize China’s investment environment,lessen the burdenson the shoulders of enterprises and enhance the level of ad-ministration over FIEs.

Probabilistic joint remote preparation of a high-dimensional equatorial quantum state

This paper proposes a scheme for probabilistic joint remote preparation of an arbitrary high-dimensional equatorial quantum state by using high-dimensional single-particle orthogonal projective measurement and appropriate unitary operation. As a special case, a scheme of joint remote preparation of a single-qutrit equatorial state is presented in detail. The scheme is also generalized to the multi-party high-dimensional case. It shows that, only if when all the senders collaborate with each other, the receiver can reconstruct the original state with a certain probability.

基于增益调整的Joint-EKF算法估算电池SOC

在电流采样过程中,电流漂移噪声会对采样精度造成干扰,进而影响锂离子电池荷电状态(SOC)估算的精度。采用联合扩展卡尔曼滤波(Joint-EKF)算法,以Thevenin模型为等效电路模型基础,将电流漂移值与状态变量同步预测,可提高估算精度。在电流突变时,需要加快算法修正速度来解决算法跟踪效果差的问题。基于Joint-EKF算法,通过调整滤波增益动态修正SOC,可进一步提高SOC估算精度。结果表明:改进算法后的SOC估算误差为2.8%,比改进前的减小2.4%。

Shear strength criteria for rock,rock joints,rockfill and rock masses:Problems and some solutions

Although many intact rock types can be very strong,a critical confining pressure can eventually be reached in triaxial testing,such that the Mohr shear strength envelope becomes horizontal.This critical state has recently been better defined,and correct curvature or correct deviation from linear Mohr-Coulomb（MC） has finally been found.Standard shear testing procedures for rock joints,using multiple testing of the same sample,in case of insufficient samples,can be shown to exaggerate apparent cohesion.Even rough joints do not have any cohesion,but instead have very high friction angles at low stress,due to strong dilation.Rock masses,implying problems of large-scale interaction with engineering structures,may have both cohesive and frictional strength components.However,it is not correct to add these,following linear M-C or nonlinear Hoek-Brown（H-B） standard routines.Cohesion is broken at small strain,while friction is mobilized at larger strain and remains to the end of the shear deformation.The criterion ＇c then σn tan φ＇ should replace ＇c plus σn tan φ＇ for improved fit to reality.Transformation of principal stresses to a shear plane seems to ignore mobilized dilation,and caused great experimental difficulties until understood.There seems to be plenty of room for continued research,so that errors of judgement of the last 50 years can be corrected.

Anti-Windup Control Strategy of Drive System for Humanoid Robot Arm Joint

To address the problems of torque limit and controller saturation in the control of robot arm joint,an anti-windup control strategy is proposed for a humanoid robot arm,which is based on the integral state prediction under the direct torque control system of brushless DC motor. First,the arm joint of the humanoid robot is modelled. Then the speed controller model and the influence of the initial value of the integral element on the system are analyzed. On the basis of the traditional antiwindup controller,an integral state estimator is set up. Under the condition of different load torques and the given speed,the integral steady-state value is estimated. Therefore the accumulation of the speed error terminates when the integrator reaches saturation. Then the predicted integral steady-state value is used as the initial value of the regulator to enter the linear region to make the system achieve the purpose of anti-windup. The simulation results demonstrate that the control strategy for the humanoid robot arm joint based on integral state prediction can play the role of anti-windup and suppress the overshoot of the system effectively. The system has a good dynamic performance.

Joining of 25CePO_4/ZrO_2 and ZrO_2 on Green State Without Pressure

High-yielding low-cost vanadium oxide nanotubes were prepared by hydrothermal self-assembling process from vanadium pentoxide and organic molecules as structure-directing templates. Moreover, a new method was discovered to determine the content of V (IV) in vanadium oxide nanotubes by thermogravimetric analysis (TGA). This method can be extended to determine the content of low oxidation state in other transition metal oxide nanomaterials.

Changes in the Structure and Properties of the Cu-Pb Composites Interface Jointed in the Solid Phase

Research of structure and properties of Cu-Pb-Cu composite interface, obtained by technology of pack rolling of the pair of mutually insoluble metals, was performed using the methods of metallography, micro- and nano-hardness, mechanical tests, energy-dispersion elementary analyses. The work was aimed at the analyses of possible mechanical mechanisms of mass-transfer, determining the hardness of metal joint in conditions of absence of inter-diffusion. It was shown that different intensity of mass transfer of copper and lead takes place through the composite interface, which corresponds to the results obtained on the other system of dissimilar materials—copper-niobium. Qualitative explanation of these patterns was offered on the basis of more intensive plastic flow of fusible compound of the composite in conditions of roll-bond joining.

燃料电池增程式动力系统能量管理策略研究

以某款纯电动客车为研究对象,以增加车辆续驶里程为目的,提出燃料电池增程式混合动力系统结构,根据性能指标对动力系统各部件进行匹配计算和选型.提出了开关/功率跟随式能量管理策略,基于Cruise和Simulink分别搭建了整车动力系统模型和燃料电池及能量管理策略模型并进行联合仿真.结果表明,采用文中提出的能量管理策略车辆经济性相对于开关式和能量跟随式两种控制策略分别提高62%和31%,续驶里程相对于该两种控制策略分别提高41%和18%.

Modified Joint Distribution of Wave Heights and Periods

The modified versions of the linear theoretical model of Longuet-Higgins （1983） are derived in this work and also compared with the laboratory experiments carried out in MAR1NTEK. The main feature of modifications is to replace the mean frequency in the formulation with the peak frequency of the wave spectrum. These two alternative forms of joint distributions are checked in three typical random sea states characterized by the initial wave steepness. In order to further explore the properties ＆these models, the associated marginal distributions of wave heights and wave periods are also researched with the observed statistics and some encouraging results are obtained.

基于输入−状态联合估计的漂浮式风机塔架结构载荷反演及状态分析

[目的]旨在研究波浪作用下漂浮式风机塔架的结构载荷反演方法及动力响应状态。[方法]以半潜型风机为研究对象,通过时域仿真模拟测量数据,并且基于漂浮式风机的频域仿真模型计算塔架的质量归一化模态,将二者作为输入−状态联合估计(joint input-state estimation,JIS)算法的输入,对漂浮式风机塔架开展结构载荷反演以及实时状态分析。[结果]结果表明:基于JIS算法,以塔架节点的仿真数据作为算法的输入,估计的塔根载荷以及塔架节点响应与仿真结果具有良好的一致性,实现了高精度的反演。[结论]反演结果验证了JIS算法的有效性,可以用于漂浮式风机的实时状态分析,保障漂浮式风机长期安全稳定运行。

基于全新电热耦合模型的锂电池关键状态在线联合估计方法

面向电动汽车一类宽温度,大幅值、宽频率随机电流应用场景,提出一种基于全新电热耦合模型的锂电池多状态在线联合估计方法。该模型由自回归等效电路模型与单态集总热模型耦合而成,以提高模型电气动态跟随性能。电热耦合模型参数采取“先验信息初始化-在线修正”的方式确定,以避免电池一致性问题带来的误差,从而实现电热耦合关系在宽温度内的连续准确表达。基于所提出的ARST(autoregression-single state thermal model)耦合模型,该文采用双滤波算法实现锂电池多状态的在线联合估计,弥补目前电池3种及以上状态联合估计的稀缺问题。最后,在[0,50]℃,基于两个动态工况,将所提出的算法与两类基于模型的多状态联合估计算法进行比较。结果表明:ARST模型具有更好的电气跟随性能;所提出的模型参数在线辨识算法能够有效提高模型精度,从而提高多状态联合估计精度;在宽温度应用中,相较仅基于电模型的多状态联合估计算法,兼顾热状态估计的多状态联合估计算法能够有效提高电池状态的估计精度。

基于超声声速的硅橡胶老化状态诊断方法

电缆接头硅橡胶会受到电、热等多方面因素影响,发生绝缘性能的老化和失效,为无损检测硅橡胶老化状态,本文提出了一种基于超声声速的硅橡胶老化状态诊断方法。制备了不同老化时间的硅橡胶试样并测量其密度和弹性模量,通过仿真及试验验证了硅橡胶超声声速与老化状态的相关性,试验结果表明,硅橡胶声速与老化状态的拟合优度均在0.8以上,利用超声声速可以准确表征硅橡胶老化状态。