The pressure compensation technology of deep-sea sampling based on the real gas state equation

Compressed gas is usually used for the pressure compensation of the deep-sea pressure-maintaining sampler.The pressure and volume of the recovered fluid sample are highly related to the precharged gas. To better understand the behavior of the gas under high pressure, we present a new real gas state equation based on the compression factor Z which was derived from experimental data. Then theoretical calculation method of the pressure and volume of the sample was introduced based on this empirical gas state equation. Finally, the proposed calculation method was well verified by the high-pressure vessel experiment of the sampler under 115 MPa.

基于EtherCAT总线的八轴七联动高级海况环境仿真平台

针对水流模拟海况时存在的运动不受控以及常规海况模拟平台模拟海况等级低,运动自由度不足等问题,提出利用八自由度运动平台模拟高级海况环境进行海浪涌动测试的方法。设计了由直线运动平台、旋转机构和6自由度(6-DOF)并联机构组成的串并联混合八自由度高级海况环境仿真平台,其运动加速度大,自由度多,运动方式多样。基于Ether CAT实时总线技术设计了八轴七联动的运动控制算法,并采用惯量匹配技术抑制抖动和噪声,实现了宽惯量范围的精确、稳定、同步(小于1μs)控制。设计了基于外部信号接收器的实时精密补偿技术和双齿轮消隙技术,提高了速率精度和平稳性,定位精度达到10μm。设计了复合叠加摇摆、文件仿真、复合叠加摇摆与文件仿真叠加运动和实时仿真运动方式,可模拟到五级高海况或将实航数据回灌后模拟水下、水面或机载的运动,用于导航系统的姿态模拟测试。

Important Guarantee for The Basic Rights of Citizens——China's State compensation system

A common folk can sue an official? This was hardly possible in the past in China where the old feudalistic tradition dies hard. But this is really possible today when the common people cannot only sue officials and also get compensation if they are wronged. State compensation system It would be inevitable for government functionaries to cause damages to some citizens, legal persons or other organizations in the course of their management of the society. That is why China has established a State compensation system to compensate for the damages to citizens, legal persons and other organizations caused by government functionaries in exercising their power.

A Fixed-Point Fast Sweeping WENO Method with Inverse Lax-Wendroff Boundary Treatment for Steady State of Hyperbolic Conservation Laws

Fixed-point fast sweeping WENO methods are a class of efficient high-order numerical methods to solve steady-state solutions of hyperbolic partial differential equations(PDEs).The Gauss-Seidel iterations and alternating sweeping strategy are used to cover characteristics of hyperbolic PDEs in each sweeping order to achieve fast convergence rate to steady-state solutions.A nice property of fixed-point fast sweeping WENO methods which distinguishes them from other fast sweeping methods is that they are explicit and do not require inverse operation of nonlinear local systems.Hence,they are easy to be applied to a general hyperbolic system.To deal with the difficulties associated with numerical boundary treatment when high-order finite difference methods on a Cartesian mesh are used to solve hyperbolic PDEs on complex domains,inverse Lax-Wendroff(ILW)procedures were developed as a very effective approach in the literature.In this paper,we combine a fifthorder fixed-point fast sweeping WENO method with an ILW procedure to solve steadystate solution of hyperbolic conservation laws on complex computing regions.Numerical experiments are performed to test the method in solving various problems including the cases with the physical boundary not aligned with the grids.Numerical results show highorder accuracy and good performance of the method.Furthermore,the method is compared with the popular third-order total variation diminishing Runge-Kutta(TVD-RK3)time-marching method for steady-state computations.Numerical examples show that for most of examples,the fixed-point fast sweeping method saves more than half CPU time costs than TVD-RK3 to converge to steady-state solutions.

Event-triggered model-free adaptive control for a class of surface vessels with time-delay and external disturbance via state observer

This paper provides an improved model-free adaptive control(IMFAC)strategy for solving the surface vessel trajectory tracking issue with time delay and restricted disturbance.Firstly,the original nonlinear time-delay system is transformed into a structure consisting of an unknown residual term and a parameter term with control inputs using a local compact form dynamic linearization(local-CFDL).To take advantage of the resulting structure,use a discrete-time extended state observer(DESO)to estimate the unknown residual factor.Then,according to the study,the inclusion of a time delay has no effect on the linearization structure,and an improved control approach is provided,in which DESO is used to adjust for uncertainties.Furthermore,a DESO-based event-triggered model-free adaptive control(ET-DESO-MFAC)is established by designing event-triggered conditions to assure Lyapunov stability.Only when the system’s indicator fulfills the provided event-triggered condition will the control input signal be updated;otherwise,the control input will stay the same as it is at the last trigger moment.A coordinate compensation approach is developed to reduce the steady-state inaccuracy of trajectory tracking.Finally,simulation experiments are used to assess the effectiveness of the proposed technique for trajectory tracking.

On the Normative Structure of International Human Rights Treaties Monitoring Mechanisms and Its Legal Challenges

The Charter bodies established under the United Nations Charter and the treaty bodies established on the basis of international human rights treaties constitute the two major means of supervising the implementation of international human rights treaties.The treaty bodies responsible for monitoring the implementation of international human right treaties have gradually formed a four-fold supervision system consisting of state reporting,inter-state complaints,individual complaints and inquiry procedures.These quasi-judicial procedures are responsible for overseeing the implementation of international human right treaties.The practice of treaty body procedures has profoundly affected the development of modern international human rights law and is promoting the improvement of international human right treaty monitoring mechanisms.But due to the constraints of international politics,economic structure and related historical conditions,treaty bodies still face severe challenges.The improvement of the four major procedures will promote the development of the international human rights cause.

Simple Procedure for Entanglement Transformation of Bipartite Pure States

<Abstract>An explicit procedure for transforming one bipartite entangled state into another via local operations and classical communication (LOCC) is presented.Our procedure is much simper than the previous ones in the sense that,it only involves two steps and the explicit expression of local general measurement used in the procedure can be obtained by solving a set of linear equations,Furthermore,this procedure is still applicable in high dimensional case.

Non-Isothermal Desolvation Kinetics of Erythromycin A Acetone Solvate

The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar method and Coats-Redfern method to fit various solid-state reaction models, and to achieve kinetic parameters of desolvation. The mechanism of thermal desolvation was evaluated using the kinetic compensation effect. The results show that kinetics of desolvation of erythromycin acetone solvate was compatible with the mechanism of a two-dimensional diffusion controlled and was best expressed by Valensi equation. Corresponding to the integral method and the differential method, the activation energy of desolvation of erythromycin acetone solvate was estimated to be 51.26—57.11 kJ/mol, and the pre-exponential factor was 8.077×106 s-1—4.326×107 s-1, respectively.

Proportional-derivative Control of Second-order Tethered Satellites System Based on Extended State Observer and Feed-forward Compensation

This paper researches the proportional-derivative(PD)feedback control with feed-forward compensations from input for a triangular tethered satellite system(TTSS),and the extended state observer(ESO)design which is further incorporated in control to estimate the structural uncertainties in system.By expanding Lagrangian equations under chosen variables,the dynamic equations of TTSS are derived which is the second-order nonlinear equation.Then the feedback control under typical feed-forward compensations is discussed as the nonlinear functions in system are counteracted,and the controlled outputs are computed by deriving the transfer functions of the transformed structures.Moreover,in case of the uncertain structures in system which may constrain the control e®ect,ESO-based PD control is further proposed,and the observed error and controlled accuracy are analyzed by Lyapunov functions.Simulation results on the designed controls are presented to validate the theoretic analyses.

Assessment of immunization procedures for foot-and-mouth disease in large-scale pig farms in China based on actual data and dynamics

Foot-and-mouth disease(FMD)is an acute,highly infectious and pathogenic animal disease.In recent years,with the rapid development of the swine breeding industry in China,pig farms have shown a trend of larger-scale development.Large-scale pig farms employ standardized management,a high level of automation,and a strict_system.However,these farms have a large trading volume,and increased transmission intensity of FMD is noted inside the farm.At present,the main control measure against FMD is pig vaccination.However,a standard for immunization procedures is not available,and currently adopted immunization procedures have not been effectively and systematically evaluated.Taking a typical large-scale pig farm in China as the research subject and considering the breeding pattern,piggery structure,age structure and immunization procedures,an individual-based state probability model is established to evaluate the effectiveness of the immune procedure.Based on numerical simulation,it is concluded that the optimal immunization program involves primary immunization at 40 days of age and secondary immunization at 80 days of age for commercial pigs.Breeding boars and breeding sows are immunized 4 times a year,and reserve pigs are immunized at 169 and 259 days of age.According to the theoretical analysis,the average control reproduction number of individuals under the optimal immunization procedure in the farm is 0.4927.In the absence of immunization,the average is 1.7498,indicating that the epidemic cannot be controlled without immunization procedures.

A State Compensation Case & Its Lessons

It was 7 o’clock on November 17, 2001. Chen Qinglong, a hired driver in Dongguan City, Guangdong Province, was driving his vehicle to the checkpoint at Changping town of the city. A security guard of the town’s public security bureau blocked his way on the pretext that "his vehicle bumped into a security guard and injured him a few days ago." Then, a policeman from a sub-police station in Changping Town took Chen and his vehicle to the sub-police station.

基于改进ESKF的植保无人机时延位姿补偿算法

为解决全球导航卫星系统和惯性测量单元融合时间不同步问题,提高植保无人机位姿估计精度,本文根据植保无人机大惯性、强振动的特性提出一种基于改进误差状态卡尔曼的时延位姿补偿算法。首先对名义状态变量线性预测,引入渐消因子提高强振动环境下的系统稳定性;接着采用互补滤波对角速度补偿,对姿态误差状态变量修正;最后结合测量的延迟时间,使用互补滤波外推数据,提高大惯性特性下的速度位置精度。实验结果表明,相较于误差状态卡尔曼算法,横滚角和俯仰角均方根误差减少0.2669°和0.2414°,偏航角均方根误差减少0.0764°;正常航迹植保作业下,东北天方向速度均方根误差减少0.2105、0.1849、0.2388 m/s;东北天方向位置均方根误差分别减少0.21、0.19、0.23 m,有效提高位姿估计精度。

国有企业职业经理人制度改革研究

我国的改革是对社会主义制度的自我完善,其中,国有企业改革需要将加强党的领导与市场化发展统一起来。因此,国有企业职业经理人制度改革,必须坚持中国特色社会主义市场化改革的方向,采取分类分层改革的方式,以市场化选聘、契约化管理、差异化薪酬、市场化退出为重点环节,因企制宜、循序渐进地推进。改革开放以来,我国国有企业职业经理人制度改革经历了改革准备、初步酝酿、试水调整、推广深化四个阶段,探索形成了四化管理、自愿转身、灵活市场化、部分市场化等典型模式,取得了显著成效,但还存在市场化选聘未能达到预期效果、契约化管理存在难点、差异化薪酬设计不合理、市场化退出机制不完善、监管及配套机制不健全等问题。应坚持党管干部、党管人才的原则,重塑企业文化,增强市场观念,充分发挥市场机制作用,弘扬企业家精神,完善治理体系,逐步建设具有中国特色的现代职业经理人制度体系。

妇科肿瘤患者心理护理干预模式规范化程序的实施

目的 评价一般护理与心理护理在妇科肿瘤患者对心境状态、睡眠等影响效果。方法 将2022年11月至2023年11月期间江苏省徐州市妇幼保健院确诊的90例妇科肿瘤患者纳为研究对象,进行分组研究。使用随机法选择45例患者命名为观察组(心理护理干预模式规范化程序),另45例患者命名为对照组(一般护理)。评价心理护理与一般护理对患者心境状态、睡眠的影响。结果 护理前,两组紧张、抑郁、慌乱等POMS评分对比,差异无统计学意义(均P> 0.05);护理后,两组紧张、抑郁、慌乱等心境状态量表(POMS)指标得分较护理前均降低,且观察组低于对照组(均P <0.05);观察组睡眠时间、睡眠质量、睡眠障碍、睡眠效率等匹兹堡睡眠质量评分量表(PSQI)指标评分均低于对照组(均P <0.05)。结论 癌症是危及人类身心健康的重要疾病,尤其是妇科肿瘤,对女性生理、心理影响较大。情绪对疾病预后改善较为直接,因而辅以护理干预措施具有重要作用。试验通过实施心理护理规范化程序使患者恐惧、失望、忧郁等心境状态得到改善,客观公正认识肿瘤并积极配合护理实施,减轻生活影响,保持良好睡眠质量。由此可见,妇科肿瘤患者施行心理护理干预模式规范化程序利于改善不良心境,提高睡眠质量,且满意率占比高,护理作用显著。

电网电压三相不平衡时FMSS正负序电流补偿型VSG控制

柔性多状态开关(FMSS)是一种取代传统联络开关应用于现代配电网的新型电力电子设备,能够优化现代配电网分布式电源的消纳和调控。和传统控制算法相比,采用VSG控制的FMSS不受弱电网环境下锁相环性能恶化的影响,在低电网强度下能够向电网提供频率支撑,从而增强系统的稳定性。FMSS作为接入配电网的装置,当电网电压发生三相不平衡现象时,传统VSG控制下的FMSS输出电流、功率会发生明显的波动,并网点的效率会大大降低。针对此问题,以模块化多电平变流器(MMC)结构为基础,在VSG控制策略的基础上引入正负序电流补偿,分别实现不平衡电网下FMSS输出电流、有功功率及无功功率的稳定。最后,通过Matlab/Simulink搭建四端FMSS模型,利用仿真验证所提控制策略的有效性。

基于LESO的PMSM转子位置估算误差补偿方法

高速永磁同步电机运行中,转子位置精确与否确定了系统运行性能优劣,对于只补偿一拍滞后和零阶保持器引起的角度误差,以及通过与前馈解耦做差获得误差角进行补偿的方法,在精度和动态性等方面性能欠佳。为此,通过分析转子位置估算误差产生原因,推导出误差角的通用型数学模型,提出一种基于线性扩张状态观测器(LESO)的转子位置估算误差补偿方法。基于推导模型设计出一种可提取转子位置误差角的LESO,并采用获得的转子位置误差角进行补偿。此转子位置误差角估算考虑了不同类型非理想因素的影响,以及动态过程中电感电压项对误差角的影响,精度高、动态性好。最后搭建系统实验平台,实验结果表明所提转子位置估算误差补偿方法在精度和动态性方面具有优势。

基于特征模型的5阶关节伺服系统扰动补偿策略

针对工业机器人关节伺服系统负载时变和模型不确定性问题,提出将线性扩张状态观测器和基于特征模型的全系数自适应控制相结合的控制策略。建立双惯量柔性关节动力学模型并得到关节伺服系统5阶扩张状态方程。基于该模型设计5阶线性扩张状态观测器,通过该观测器估计系统总扰动并进行扰动补偿,并证明观测器收敛性。基于特征建模的方法,通过实验数据和梯度下降法对特征参数进行辨识,并基于参数值设计全系数自适应控制律,将该控制律结合线性扩张状态观测器设计一种控制策略,对系统进行精确控制。实验结果表明,新的控制策略使系统在变负载扰动工况下的定位精度达到0.003°,正弦信号跟踪误差保持在0.92°以内,系统具有较强的鲁棒性和控制精度。

基于平滑GMS模型和改进扩张状态观测器的复合摩擦补偿

摩擦力是影响直线伺服系统低速运行与点对点定位精度的主要非线性扰动。广义麦克斯韦(generalized Maxwellslip,GMS)摩擦模型虽然可以准确描述摩擦特性用于前馈补偿,但其存在切换点过渡时振荡的问题,同时易受测量噪声和摩擦参数变化等影响。为此,该文提出基于平滑GMS模型和改进扩张状态观测器(extended state observer,ESO)的复合摩擦补偿策略。首先,引入过渡用双曲正切函数以解决GMS模型中在切换点的反复穿越问题,并给出该模型的离线辨识方法。其次,设计基于模型信息的四阶ESO补偿剩余摩擦力与未知扰动,并引入切比雪夫滤波器整定观测器增益,以降低扰动观测与噪声敏感之间的冲突。为验证所提摩擦补偿策略的有效性,在小型高精度永磁同步直线电机定位平台上进行定位实验。实验结果验证了所提摩擦补偿策略的可行性和有效性。

四天教学周:美国发展乡村教育的政策举措

四天教学周是美国应对乡村教育资源和环境问题的重要政策举措。这一政策在20世纪30年代萌芽,发展过程中主要作用于乡村教育资金的节省,近年来作为消费型补偿吸引和保留乡村教师的作用凸显。四天教学周的政策制定者通过发布政策规定,明确实施要求,政策实施者基于当地资源,形成差异化实施方式。在政策实施后,政策制定者和实施者需要针对教师和学生进行政策评估。这一政策的成效主要表现在节省资金并调整资金结构,保障教师工资;改善工作环境,吸引和留住教师;调动教师积极性,促进学生发展。但是这一政策在实施效果及对教师和学生的影响等方面引发了诸多争议。研究从消费型补偿的视角,分析了四天教学周从教师工资和工作环境两方面协同发力促进乡村教师和乡村教育发展的经验及启示。

面向永磁同步电机负载转矩观测的自抗扰改进滑模控制

针对传统永磁同步电机滑模控制中存在的滑模抖振大及响应速度慢的问题,设计了一种新型趋近律,在传统指数趋近律的基础上加入可变比例系数并引入系统状态变量和滑模面的幂次项,减小抖振的同时提高了趋近速率。随后,为了避免引入转速误差的微分项,减小系统高频抖振,采用积分滑模面,设计了永磁同步电机改进滑模速度控制器。针对控制策略中负载扰动波动会导致系统控制精度降低、抖振增大的问题,设计了一种基于新型饱和函数的扩张状态观测器估计负载扰动,并将扰动估计值前馈至改进滑模控制器中,进一步提高了系统的抗扰性能。数值仿真结果表明:所提出的控制策略可显著提高电机动态性能和抗扰性。在电机受负载转矩波动影响时,比PI控制电机超调量减小约23.1%,响应速度提高62.5%,比传统滑模控制电机超调量减小约15.3%,响应速度提高50%。新型滑模趋近律还可以有效降低滑模抖振,与传统滑模控制器相比,采用改进滑模控制器电机抖振降低约50%。