Non-Perturbative Guiding Center and Stochastic Gyrocenter Transformations:Gyro-Phase Is the Kaluza-Klein 5^(th) Dimension also for Reconciling General Relativity with Quantum Mechanics

The non perturbative guiding center transformation is extended to the relativistic regime and takes into account electromagnetic fluctuations. The main solutions are obtained in covariant form: the gyrating particle and the guiding particle solutions, both in gyro-kinetic as in MHD orderings. Moreover, the presence of a gravitational field is also considered. The way to introduce the gravitational field is original and based on the Einstein conjecture on the feasibility to extend the general relativity theory to include electromagnetism by geometry, if applied to the extended phase space. In gyro-kinetic theory, some interesting novelties appear in a natural way, such as the exactness of the conservation of a magnetic moment, or the fact that the gyro-phase is treated as the non observable fifth dimension of the Kaluza-Klein model. Electrodynamics becomes non local, without the inconsistency of self-energy. Finally, the gyrocenter transformation is considered in the presence of stochastic e.m. fluctuations for explaining quantum behaviors via Nelson’s approach. The gyrocenter law of motion is the Schrödinger equation.

Diagrammatic Approach for Investigating Two Dimensional Elastic Collisions in Momentum Space II: Special Relativity

The diagrammatic approach to the collision problems in Newtonian mechanics is useful. We show in this article that the same technique can be applied to the case of the special relativity. The two circles play an important role in Newtonian mechanics, while in the special relativity, we need one circle and one ellipse. The circle shows the collision in the center-of-mass system. And the ellipse shows the collision in the laboratory system. These two figures give all information on two dimensional elastic collisions in the special relativity.

Interaction between an Accelerated Mass in Straight Motion and a Hidden Energy Reservoir as a Strict Mathematical Consequence of Special Relativity

A. Einstein and H.A. Lorentz had found that the mass of an accelerated body traveling at relativistic velocity appears to depend on whether the acceleration is performed in the direction of motion or in a transverse direction. E.P. Epstein rejected this result in the “Annalen der Physik”;he rather postulated an additional force that turns up when the body is accelerated in the longitudinal direction. It can be shown that the concept of an increased longitudinal mass is based on a simple mathematical error. When correcting this error, it turns out that Epstein’s additional, hidden force is indispensable in order to avoid an inner inconsistency of Special Relativity. It does most of the total work absorbed by the moving object, and is thus responsible for most of the increase in its energy (=mass), given the speed attained is relativistic. In other words: While the total force on the body needed to maintain a constant acceleration a0 is “(1-v2/c2)-1ma0=m0(1-v2/c2)-3/2a0”, the technical force needed to maintain that acceleration amounts only to “ma0=m0(1 - v2/c2)-1/2a0”. The total energy of two objects that undergo a symmetrical, elastic head-on collision is therefore not conserved during the collision, thus requiring the involvement of a hidden reservoir of energy. This result is confirmed by calculations that use the concept of momenergy. The phenomenon of an apparent disappearance of energy has been noticed in particle physics already (target-experiment), but its consequences have been ignored. Instead, an explanation has been given (reduced “energy of the center of mass”) which is inconsistent and violates the relativity principle.

基于HSS模型海上风电桶形基础水平循环承载特性对比研究

采用土体本构模型对黏土中的桶形基础进行了有限元模拟,以研究桶形基础的水平循环承载特性。利用有限元方法模拟了在不同单调组合荷载作用下黏土中的桶形基础离心机试验,与试验结果对比验证了使用小应变硬化土(HSS)本构模型的适用性。在此基础上,基于HSS模型和硬化土(HS)模型对比研究了不同循环荷载和小应变模量对桶形基础累积转角、旋转中心和桶-土相对刚度的影响。结果表明,黏土中桶形基础的累积转角随着循环次数和水平荷载的增加而增加,然而每个循环中累积转角的增加逐渐减小。另外,提出了Tb和ζb之间的拟合关系式预测黏土中桶形基础的累积旋转。无论处于疲劳极限状态(ζb=0.3)还是正常使用极限状态(ζb=0.5),旋转中心类型都是从深中心变为浅中心。桶-土相对刚度随循环次数的增加而减小,并且循环荷载越大刚度衰减越大。另外,小应变模量对基础累积转角和桶-土相对刚度有较大影响而对旋转中心无显著影响。与已有的研究结果对比发现,HSS模型更加适用于精细化设计。

孕育希望:宏观代际流动性对生育意愿的影响

当今中国,子女在家庭中仍处于中心位置,父母对子女福祉的重视会影响其生育决策。本文使用中国综合社会调查(CGSS)2010—2018年数据,考察了宏观社会流动性对生育意愿的影响。研究结果表明,相对流动性与期望子女数显著正相关,主观态度是重要的中介影响机制。从子代地位预期与抚育成本预期的视角出发,相对流动性的影响呈负社会经济梯度,但流动性的提升不会抑制高社会阶层的生育意愿;性别差异在社会化视角中被强调,男性受流动性的影响更强,并且流动性与期望男孩数关联更加密切。本研究从宏观层面丰富了对低生育率现象的理解,对从微观层面分析流动效应的研究也有借鉴意义。本文认为,机会公平政策应当作为当下中国生育促进政策的一个重要构成。

基于自适应中心误差熵的相对导航滤波算法

基于中心误差熵准则的卡尔曼滤波算法在非高斯噪声下具有强鲁棒性,但仍面临权值系数如何选择的难题。针对上述问题,提出一种变权值系数的自适应中心误差熵卡尔曼滤波算法。该算法将误差矢量引入权值系数更新函数,增强了代价函数对误差的敏感性,提高了算法的滤波精度。将其应用于编队卫星相对导航,仿真结果表明,相比于卡尔曼滤波算法和中心误差熵卡尔曼滤波算法,所提算法在处理线性非高斯系统的状态估计问题时表现出了良好的滤波性能,具有更高的滤波精度和对非高斯噪声更强的抑制能力。

基于相对距离和历史成功率机制的增强麻雀搜索算法

针对麻雀搜索算法收敛精度低、易陷入局部最优等问题,提出了一种融合相对距离和历史成功率的增强麻雀搜索算法(RHSSA)。首先,RHSSA引入一种融合适应度值与相对距离的发现者选择方式,使选出的发现者既保持较高质量,又保持在搜索空间的分布广泛;其次,RHSSA在麻雀发现者搜索过程中,采用融合加权重心的反向学习策略,充分挖掘搜索空间的优质位置信息并减弱发现者向原点聚集的趋势;最后,RHSSA引入基于历史成功率的自适应选择算子动态地选择柯西变异与高斯变异对最优解做扰动,提高算法跳出局部最优的能力。选用CEC2017测试函数集中的12个函数作为性能基准函数,将RHSSA与其他五种改进的麻雀搜索算法(AMSSA、SCSSA、SHSSA、ISSA、CSSOA)进行性能评测。基于实验数据的Friedman检验表明,RHSSA能获取最优的结果。为验证提出的改进策略的有效性,还对改进策略进行了消融实验。实验结果表明在综合改进策略的共同作用下,RHSSA的综合优化性能排名为第一名。

Relationships Between the Distribution of Relative Canopy Light Intensity and the Peach Yield and Quality

The aim of the present experiment was to study the relationship between the distribution of relative light intensity in canopy and yield and quality of Wanmi peach. The optimum relative canopy light intensity was judged to be 36.3% for high quality peaches, when canopy volumes of Wanmi peach trees with a relative light intensity 〈 30% accounted for 7.7 and 47.9% of the total canopy volume in June and September, respectively. The canopy volume with a relative light intensity 〉 80% was 27.7 and 3.1% of the total canopy volume in June and September, respectively. Peach canopies were divided into 0.5 m × 0.5 m × 0.5 m cubes, with the relative light intensity being measured at different positions of the canopy during the growing season. Yield and fruit quality were also measured at these positions at harvest. The results showed that the relative light intensity decreased gradually from outside to inside and from top to bottom of the tree canopy. Fruit were mainly distributed in the upper and middle portions of the canopy, 1.5-3.0 m above ground. Regression results showed that single fruit weight and soluble solid content were positively related to relative light intensity.

Study on Approach for Computer-Aided Design and Machining of General Cylindrical Cam Using Relative Velocity and Inverse Kinematics

Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa tic transfer equipments. This paper proposes a new approach for the shape design and manufacturing of the cylindrical cam. The design approach uses the relative velocity concept and the manufacturing approach uses the inverse kinematics concept. For the shape desig n, the contact points between the cam and the follower roller are calculated bas ed on relative velocity of which the direction is on the common tangential line, and then the whole shape of cam is determined from transformation of the coordi nate system. For the manufacturing procedures, the location and the orientation of cutter path can be allocated corresponding to the designed shape data. The in tegral NC code for multi-axis CNC machining center is created using the inverse kinematics concept from the data of the location and the orientation of cutter path. As the advantages of the proposed approach, the machine tool is designed t o having an alternative size in fabricating the general cam, while the tool must be fitted to diameter size of the follower in the conventional approach. Finally, CAD/CAM program, "Cylindrical DAM", is developed on C++ lan guage. This program can perform shape design, manufacturing and kinematics simul ation, which can make integral NC code for multi-axis CNC machining center. The proposed method can be applied easily on fields of industries.

A New Formulation for General Relativistic Force-Free Electrodynamics and Its Applications

We formulate the general relativistic force-free electrodynamics in a new 3 ＋ 1 language. In this formulation, when we have properly defined electric and magnetic fields, the covariant Maxwell equations could be cast in the traditional form with new vacuum constitutive constraint equations. The fundamental equation governing a stationary, axisymmetric force-free black hole magnetosphere is derived using this formulation which recasts the Grad-Shafranov equation in a simpler way. Compared to the classic 3＋1 system of Thorne and MacDonald, the new system of 3＋1 equations is more suitable for numerical use for it keeps the hyperbolic structure of the electrodynamics and avoids the singularity at the event horizon. This formulation could be readily extended to non-relativistic limit and find applications in fiat spacetime. We investigate its application to disk wind, black hole magnetosphere and solar physics in both fiat and curved spacetime.

Numerical simulation of the Moon's rotation in a rigorous relativistic framework

This paper describes a numerical simulation of the rigid rotation of the Moon in a relativis- tic framework. Following a resolution passed by the International Astronomical Union （IAU） in 2000, we construct a kinematieally non-rotating reference system named the Selenocentric Celestial Reference System （SCRS） and give the time transformation between the Selenocentric Coordinate Time （TCS） and Barycentric Coordinate Time （TCB）. The post-Newtonian equations of the Moon＇s rotation are written in the SCRS, and they are integrated numerically. We calculate the correction to the rotation of the Moon due to total relativistic torque which includes post-Newtonian and gravitomagnetic torques as well as geodetic precession. We find two dominant periods associated with this correction： 18.6 yr and 80.1 yr. In addition, the precession of the rotating axes caused by fourth-degree and fifth-degree harmonics of the Moon is also analyzed, and we have found that the main periods of this precession are 27.3 d, 2.9 yr, 18.6 yr and 80.1 yr.

Galactic center research:manifestations of the central black hole

This review summarizes a few of the frontiers of Galactic center research that are currently the focus of considerable activity and attention. It is aimed at pro- viding a necessarily incomplete sketch of some of the timely work being done on phenomena taking place in, or originating in, the central few parsecs of the Galaxy, with particular attention to topics related to the Galactic black hole （GBH）. We have chosen to expand on the following exciting topics： 1） the characterization and the im- plications for the variability of emission from the GBH, 2） the strong evidence for a powerful X-ray flare in the Galactic center within the past few hundred years, and the likelihood that the GBH is implicated in that event, 3） the prospects for detecting the ＂shadow＂ of the GBH, 4） an overview of the current state of research on the central S-star cluster, and what has been learned from the stellar orbits within that cluster, and 5） the current hypotheses for the origin of the G2 dust cloud that is projected to make a close passage by the GBH in 2013.

Preliminary limits of a logarithmic correction to the Newtonian gravitational potential in binary pulsars

We obtain preliminary limits on a logarithmic correction to the Newtonian gravitational potential by using five binary pulsars： PSR J0737-3039, PSR B 1534＋12, PSR J 1756-2251, PSR B 1913＋ 16 and PSR B2127＋ 11C. This kind of correction may originate from fundamental frameworks, like string theories, effective models of grav- ity due to quantum effects and the non-local gravity scheme. We estimate the upper limit of the Tohline-Kuhn-Kruglyak parameter A and the lower limit of the Fabris- Campos parameter α, which parameterize the correction and are connected to each other by αλ = -1. By analyzing the advances of periastron of these binary pulsars, we find that the preliminary upper limit of a is 0.19 ± 0.14 kpc^-1 and the prelimi- nary lower limit of ）, is -5.2 4± 3.8 kpc. They are compatible with the bounds based on dynamics of spiral galaxies but quite different from those given by solar system dynamics. These results indicate that this logarithmic correction might be more ob- servable in current timings of binary pulsars than in motions of the solar system.

基于FME的点云数据生成公路纵横断面解决方案

为解决传统公路纵横断面测量效率不高、精度较低的问题,提出了一种以LiDAR为外业数据采集手段,利用FME编写解决方案实现内业数据自动处理并完成纵横断面提取的方法,并在实际工程应用中进行了可行性验证。首先介绍了传统测量手段的不足和新技术的优势,再分析了纵横断面测量的相关要求,然后利用FME编写了一套从DWG设计线、桩号和左右宽数据、点云LAS数据中自动提取纵横断面数据的程序,最后分析了该方法在测量效率、精度、流程等方面的优势,为基于点云数据的公路纵横断面测量提供了有益参考。

叙事医学视域下以患者家庭为中心的重症监护室分诊治疗体系构建

叙事医学是具有叙事能力的医生对患者的困境共情、反思并行动的医疗实践,但完全照搬国外的叙事医学体系不符合中国国情。ICU患者多昏迷、无意识,救与不救的决定权更掌握在家属手里。患者家属和患者缺乏交流、接触,往往不了解患者的真实情况,很难与其共情,心理防线往往先崩溃,进而放弃治疗。要构建符合中国国情的、符合医院院情的、符合科室科情的、以家庭为中心的“叙事-临床医学体系”才能将叙事医学彻底融入我国现行的医疗体系,让医学更有温度、助力医生与疾病之间的博弈。笔者在叙事医学视域下从ICU接诊、分诊到以家庭为中心的诊疗体系以及平行病历书写形式的改进进行了系统的构建,并提出了医患共建平行病历这一观点,以期为今后叙事医学融入我国ICU医疗体系提供参考依据。

Transformer神经网络和轴心轨迹在燃机转子故障诊断中的应用

针对目前国内燃机电厂转子故障诊断主要依靠振动分析,无自动识别轴心轨迹设备的现状,将在自然语言处理领域大放异彩的Transformer神经网络引入转子轴心轨迹监测与识别领域,通过独立成分分析(Independent Component Analysis,ICA)与Transformer结合提升燃机转子故障诊断准确性。使用ICA代替Transformer自身的线性变换提取图片特征信息构建输入样本,为了解决自注意力机制无法捕捉位置信息的问题,提出相对位置编码方法,区别于使用较多的绝对位置编码,通过嵌入相对位置编码子层,将相对位置信息注入自注意力机制,使得Attention模块能够学习到序列的相对位置信息,可进一步提高图像识别模型的准确性,该模型对于轴心轨迹故障类型平均识别率达到93.8%。实验结果表明ICA-Transformer模型对转子轴心轨迹的识别准确率较高,对电厂运维具有一定的指导意义。

点的复合运动中任意相切型问题速度分析的一种特殊解法

对于相切型问题,实际作定轴转动刚体外形可能为任意封闭曲线,传统利用圆心到接触点距离保持不变特性选择动点的方法无法求解。针对这类问题,在教学中采用瞬时运动学分析方法,即找一特殊动点。该瞬时相对速度为零,从而得到所需要求解的运动学量,方法简单且直观。本文首先证明该特殊动点的存在性和唯一性,然后给出特殊动点的确定方法,最后给出3个求解实例。该方法在本校理论力学教学中得以实践,学生反映容易掌握和理解。

桃树冠层相对光照分布与果实产量品质关系的研究

【目的】研究桃树开心形树冠内相对光照强度与果实品质的关系。【方法】以5年生晚蜜为试材,以树干为中心,用竹竿将树冠分成不同层次、方位的50cm×50cm×50cm的立方体,在生长时期测量不同部位相对光照强度,成熟期测量不同部位果实产量和品质。【结果】桃树开心形树冠内相对光照强度随树冠由外到内、由上到下逐渐递减;在第一次叶幕形成和最终叶幕形成的两个不同时期,不同相对光照强度的树冠体积占整个树冠体积的比例差异显著,小于30%的分别占7.71%、47.91%,大于80%的分别占27.7%、3.13%;果实主要集中分布在树冠上、中部1.5～3.0m。回归方程解析得出果实单果重和可溶性固形物含量与相对光照强度均呈显著相关性。【结论】相对光照强度是影响果实单果重和可溶性固形物的主要因素,生产优质桃果实的最低相对光照强度为36.31%,生产中应注意合理进行夏季修剪,调节枝叶数量和空间分布,降低相对光照强度小于36.31%的树冠空间体积。

天线相位中心改正对GPS精密单点定位的影响

GPS卫星与接收机由于自身特性以及机械加工等原因,导致其质量中心与相位中心不重合而产生相位中心误差,进而对GPS精密单点定位产生一定影响。介绍GPS天线相位中心偏移(PCO)、变化(PCV)的原理,并分析PCO、PCV,以及不同模型改正对GPS精密单点定位的影响。结果表明,在GPS精密单点定位中,天线相位中心改正不容忽略:在平面方向上,天线相位中心改正对定位影响较小,仅为毫米级;在高程方向上,天线相位中心改正对定位影响较大,可达厘米级;与相对中心改正模型相比,绝对相位中心改正模型精度更高。

行星齿轮传动速度分析的瞬心——速度矢量法

将瞬心分析与速度矢量法相结合的瞬心—速度矢量法较转化机构法更为清晰、明了、直观。仅通过定性速度分析便可清晰地了解行星齿轮传动机构中诸构件的运动形态。应用此方法,可定性地绘制出行星齿轮传动机构速度分析图谱。从而为行星齿轮传动机构的选型设计和定性分析提供了极大方便。应用此法还可动态地解释差动、行星、定轴轮系间的有机联系;并可从本质上解释清楚用转化机构法难以解释的一些现象。