Existence and Uniqueness of Nested Regular Quadrilateral Central Configurations

Two cases of the nested configurations in R3 consisting of two regular quadrilaterals are discussed. One case of them do not form central configuration, the other case can be central configuration. In the second case the existence and uniqueness of the central configuration are studied. If the configuration is a central configuration, then all masses of outside layer are equivalent, similar to the masses of inside layer. At the same time the following relation between r(the ratio of the sizes) and mass ratio b = m/m must be satisfied in which the masses at outside layer are not less than the masses at inside layer, and the solution of this kind of central configuration is unique for the given ratio (6) of masses.

A New Kind of Conjugate-nested Central Configurations in Consisted of One Regular Tetrahedron and One Regular Octahedron

A new case configuration in R^3, the conjugate-nest consisted of one regular tetrahedron and one regular octahedron is discussed. If the configuration is a central configuration, then all masses of outside layer are equivalent, the masses of inside layer are also equivalent. At the same time the following relation between ρ（r =√3/3ρ is the radius ratio of the sizes） and mass ratio τ=~↑m/m must be satisfied τ=~↑m/m=ρ（ρ＋3）（3＋2ρ＋ρ^2）^-3/2＋ρ（-ρ＋3）（3-2ρ＋ρ^2）^-3/2-4.2^-3/2ρ^-2-^-1ρ^-2/2（1＋ρ）（3＋2ρ＋ρ^2）^-3/2＋2（ρ-1）（3-2ρ＋ρ^2）^-3/2-4（2√2）^-3ρ, and for any mass ratio τ, when mass ratio r is in the open interval （0, 0.03871633950 ... ）, there exist three central configuration solutions（the initial configuration conditions who imply hamagraphic solutions） corresponding radius ratios are r1, r2, and r3, two of them in the interval （2.639300779… , ＋∞） and one is in the interval （0.7379549890…, 1.490942703… ）. when mass ratio τ is in the open interval （130.8164950… , ＋∞）, in the same way there have three corresponding radius ratios, two of them in the interval （0, 0.4211584789... ） and one is in the interval （0.7379549890…, 1.490942703…）. When mass ratio τ is in the open interval （0.03871633950…, 130.8164950…）, there has only one solution r in the interval （0.7379549890…, 1.490942703… ）.

Existence and uniqueness of a class of double pyramidal central configurations in six-body problems

Under the necessary conditions for a double pyramidal central configuration with a diamond base to exist in the real number space, the existence and uniqueness of such configurations were studied by employing combinedly the algebraic method and numerical calculation. It is found that there exists a planar curl triangle region G in a square Q such that any point in G and given by the ratio of the two diagonal lengths of the diamond base and the ratio of one diagonal length of the base to the height of the double pyramid configuration determines a unique double pyramid central configuration, while all points in Q-G have no referance to any central configuration.

Double Pyramidal Central Configurations with a Concave Quadrilateral Base

As for a double pyramidal central configuration in 6-body problems, the case when its base is a concave polygon is studied. By advancing several assumptions according to the definition of double pyramidal central configuration and deducing two theorems and two corollaries on this subject, the essential and sufficient conditions to form a double pyramidal central configuration with a concave quadrilateral base are demonstrated.

Existence and uniqueness for a class of double pyramidal central configurations with a concave pentagonal base

Based on some necessary conditions for double pyramidal central configurations with a concave pentagonal base, for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with a concave pentagonal base in 7-body problems are proved and the range of the ratio between radius and half-height is obtained, within which the 7 bodies involved form a central configuration or form uniquely a central configuration.

Eight-body central configuration for conjugate-nested regular tetrahedrons

The sufficient and necessary conditions, the existence and uniqueness of a new class of central configuration in R^3, for the conjugate-nest consisting of two regular tetrahedrons, are proved. If the configuration is a central configuration, then all masses of outside layer are equivalent, and the masses of inside layer are also equivalent. At the same time p （the ratio of the sizes） and mass ratio τ=m^/m must be satisfied by some formulas. For any radius ratios ρ∈（0, 0.152996 918 2） or （0.715 223 148 7, 1.398 165 037）, there is only one central configuration. Otherwise, for any given mass ratio τ, there may exist more than one central configuration.

Existence and uniqueness for a class of nine-bodies central configurations

On some necessary conditions for double pyramidal central configurations with concave heptagon for any given ratio of masses, the existence and uniqueness of a class of double pyramidal central configurations with concave heptagon base for nine-body problems is proved in this paper, and the range of the ratio cr of the circularity radius of the heptagon to the half-height of the double pyramidal central configuration involved in this class configurations is obtained, which is in the interval （√3/3,1.099 600 679）, and the configuration involved in the bodies with any σ∈ （√3/3, 1.099 600 679） can form a central configuration which is a uniquely central configuration is proved.

Summary of current research on Central Asian vortex

The Central Asian vortex (CAV) is an important synoptic-scale system that causes rainstorms, short-term heavy precipitation, hail, and sustained low temperatures in Xinjiang. This paper summarizes the current research conducted on the CAV since the 1960s. The objective definition of the CAV has been revised and a deep and shallow CAV classification proposed. Two high-frequency areas of deep CAVactivity are the Kazakhstan hills (Sayan mountains) and the eastern area of the Aral Sea (Tashkent); events mostly occur in summer and 40% cause strong rainfall. In addition, two high-frequency activity areas of the shallow CAV are located in the west and south of the Pamirs Plateau and mostly occur in spring; 23.2% of occurrences cause strong rainfall. The western and eastern water vapor transport relates to westerlies and a strong lowlevel easterly jet stream (LLEJ) extending from Gansu to Xinjiang, respectively, and water vapor over the Tibetan Plateau transports even more northwards and enters Xinjiang. The deep CAV has an obvious cold core structure down to 300 hPa. The conversion terms from eddy available potential energy eAET to eddy kinetic energy eKET and eddy kinetic energy inflow eBKET from the open atmospheric region boundaries are the main sources of KE which cause rapid development of the CAV. The anomalous anti-cyclone center over the northeast Atlantic is the fountain of Rossby wave energy dispersion; Rossby waves propagate from the northeast Atlantic to eastern Europe (Urals (EEU)), and then continuously propagate to Central Asia causing development of the CAV. The CAV requires further study to characterize the meso-scale system structure and evolution characteristics. In addition, physical modeling of the severe convective weather occurring under the CAV is required to determine the critical impacts of this severe convective weather and enable forecasting and early-warning indexes.

“双高”电力系统集中式储能选址定容规划策略

为解决“双高”电网储能选址规划问题,提出包括结构性、运行性两项一级指标及功率波动泰尔熵等6项二级指标的集中式储能选址规划指标体系,建立以熵权法、TOPSIS法为单一评价及模糊Borda法为组合评价的指标体系组合评价模型,获得储能最优选址节点。然后提出基于变分模态分解的混合储能容量配置法,对储能控制功率进行模态分解,根据Hilbert边际谱区分高、低频模态并重构,将高、低频信号能量功率值分别分配给功率型及能量型储能。通过某地区算例结果验证了所提规划策略的有效性。

基于特征区域划分的巡逻配置及选址方法研究

为提高目标区域的巡逻效率,文章提出一种基于路网特征下区域划分的巡逻配置及选址方法。首先,定量分析研究区域路网密度,并基于中心度评价指标量化路网布局结构,实现研究区域划分;然后以总区域巡逻覆盖率为约束,构建以最优巡逻车数量配置为目标的规划模型;最后基于选址贪心算法求解并得出子区域覆盖率及巡逻车配置数量。结果显示,巡逻覆盖率与子区域路网等级和巡逻车速度提高带来的收益呈正相关关系。该方法可为巡逻配置及选址问题的解决提供有效途径。

Central configurations consist of two layer twisted regular polygons

In this paper, we study the existence of a special twisted regular polygonal central configuration in R3.

川中侏罗系大安寨二亚段页岩油富集有利岩性组合

我国湖相页岩层系地层中岩性组合复杂,且不同岩性组合中的页岩油含量差异较大,明确有利的岩性组合将有助于探寻页岩油富集区。以川中侏罗系大安寨二亚段页岩层系为研究对象,通过矿物组分分析和岩心观察指明了页岩层系中主要发育介壳灰岩、夹介壳层页岩、含介壳页岩和纯页岩,各岩性中发育的孔缝类型多样,其中含介壳页岩和纯页岩中顺层微裂缝更加发育。为了进一步揭示页岩层系中发育的孔缝系统,开展了一维核磁实验来确定岩石中亲油孔缝和亲水孔缝相互间的比例关系(孔缝配置)。其中介壳灰岩和夹介壳层页岩的孔缝配置值>60%,指示油气在其中的运移将受到限制;受顺层微裂缝发育的影响,含介壳页岩和纯页岩的孔缝配置值<60%,说明其中的孔缝系统能成为较好的油气运移通道。受烃源供给能力和油气运移阻力的影响,在ω(TOC)>1.0%的岩石中,相较于孔缝配置值<60%,孔缝配置值>60%的岩石具有更多残留油量且可动性较好(S1在0.86~2.19 mg/g范围,均值为1.42 mg/g;OSI值在65.96~123.21 mg/g,均值为91.98 mg/g)。最终结合研究区有机质富集特征,阐明了研究区大安寨二亚段页岩油富集有利岩性组合。

权力动态配置下的董事会中心主义

新《公司法》在公司机关权力配置上偏重董事会,有限地确立了董事会中心主义,但仍存在着以下问题:一方面,对剩余权力的归属规定阙如;另一方面,未有针对性地回应有限公司与股份公司之间的差异化治理需求。对此,应当充分利用《公司法》的留白和任意性规范所营造的规范自治空间,按照“常量经营权+变量剩余权”的董事会权力配置模式,构建适应性品格突出的中国式董事会中心主义。具言之,允许有限公司、非公开发行股份的股份公司等封闭公司的权力中心上移,由董事会向股东会让渡部分经营管理权,以提高决策效率;在以上市公司为典型的公众公司中下沉权力中心,将董事会的部分经营管理权力下放至经理层,构建监督型董事会。这一职权配置模式在耦合“所有权与经营权分离”这一现代公司治理范式的同时,也能够兼顾不同规模公司的治理实际。

SQUARE AND RHOMBUS CENTRAL CONFIGURATIONS

1.IntroductionTheproblemofdeterminingthecelltralconfigurationsofnbodymotionsisclassical.Infact,asearlyasinthe18thcelltury,LagrangeandEuleralreadysolvedtheproblemofcentralconfigurationsofthreebodies,namely,threecollinearsolutionsandoneequilateraltrian...

基于DCS系统的除尘集中控制研究

该文以除尘集中控制为研究对象,分析DCS系统的概念、结构组成,通过多方面优势充分论证DCS除尘控制系统的可行性。并从硬件配置、软件配置、网络配置、确定闭环控制组态逻辑和实现工艺联锁控制功能等环节,分析DCS系统在除尘集中控制项目中的具体方法,明确系统搭建与应用要点,围绕应用期间面临的典型问题来提出解决策略。旨在发挥DCS系统作用,改善传统旧除尘控制系统,提高控制效果,保障除尘系统运行稳定。

局域网在中试试验装置控制系统的应用

详细介绍了中海油材科院如何利用局域网解决中试试验装置分散控制的难题。通过建立局域网,将不同品牌控制系统和通信方式集中融合到一个中心控制室,成功解决了分散监控的问题,并提高了自动化控制水平。局域网的成功应用对小规模、多台套中试试验装置及实验室设备实现集中控制、信息共享具有极好的推广和借鉴意义。

智能变电站继电保护配置的展望和探讨

智能变电站中的继电保护设备作为智能电网的重要组成部分,在满足"四性"(灵敏性、选择性、速动性、可靠性)的要求下,提出其配置将分为过程层和变电站层2层。过程层针对一次设备独立配置主保护,下放到一次设备附近,最终和一次设备合为一体,保护的采样各自独立,可不依赖全站统一时钟进行采样同步,利用相对独立的同步数字体系(SDH)系统通过乒乓算法完成保护间的数据采样同步,元件保护采用分布式配置,可以利用独立的通信环完成数据收发,过程层以太网构成冗余;变电站层配置集中式后备保护,集中式后备保护采用自适应和在线实时整定技术。

瞬变电磁法中心回线装置资料解释方法的改进

中心回线装置是瞬变电磁勘探中最常用的装置之一.中心回线装置的视电阻率一般从回线中心点场的公式出发导出.在现场实际施工中,为提高工作效率,把发射回线中部三分之一的区域作为观测范围.通过对场分布特征的分析研究表明,与中心点相比,观测区边缘处的感应电动势数值偏离达15%～25%,这与广泛存在于华北型煤系中赋存深度为400～1000 m的陷落柱、导水小断层等引起的异常相比,已经不可忽略.大定源回线公式可以准确地表示任意场点的感应电动势,由此导出视电阻率无边缘效应影响;观测按照中心回线方式并保持在近区进行,可使感应电动势和视电阻率之间的转换简单而直接.理论和实际应用结果表明,这些措施进一步提高了瞬变电磁探测中心回线方法的探测精度.在有上覆低阻屏蔽层的情况下,对埋深500～700 m的陷落柱给出了了明显的异常反映,并被井下掘进所验证.

基于随机预测误差的分布式光伏配网储能系统容量配置方法

储能装置作为一种解决含分布式光伏配网系统功率波动的有效手段,其容量配置关系到补偿功率波动精度和经济性指标。为准确配置储能容量提出一种分布式光伏配网系统中储能设备容量配置方法:通过分析光伏出力短期预测误差和负荷短期预测误差的概率统计规律和随机过程,利用区间估计方法得出储能设备容量配置函数;然后利用该配置函数实现的配置方法,对储能容量在分布式配置和集中式配置两种方法下的预测误差的方差进行比较,可知储能容量分布式配置可以得到更精确的容量配置和更优的功率补偿效果。应用所提配置方法搭建实验样机,并应用于江西电网公司某分布式光伏配网系统中,验证了该方法的正确性和可行性。

中心回线装置在海底的瞬变响应特征研究

中心回线是陆地瞬变电磁探测常用的天线装置之一。分析了该天线装置在海底环境下的瞬变响应特征,并与陆地上的瞬变响应进行了对比;根据不同海底电导率时中心回线的瞬变响应差异,研究了中心回线对海底电导率的分辨能力;探讨了海水深度和装置尺寸对瞬变响应和分辨能力的影响。结果表明:中心回线对低阻海底具有很好的分辨能力,但对高阻海底的分辨能力差。在海水电导率为3.2S/m的深海环境中,半径2m的中心回线能够分辨的最小海底电导率为0.1S/m。减小海水深度可提高中心回线在晚延时对高阻海底的分辨能力,增大装置尺寸可提高中心回线在早延时对高阻海底的分辨能力,但提高程度均有限。