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1. chinaXiv:202107.00011 [pdf]

几个模糊集空间的性质

Huan Huang
Subjects: Mathematics >> Mathematics (General)

This paper discusses the properties the spaces of fuzzy sets in a metric space?equipped with the endograph metric and the sendograph metric, respectively.?We fist give some relations among the endograph metric, the sendograph?metric and the Γ-convergence, and then investigate the level characterizations?of the endograph metric and the Γ-convergence. By using the above results,?we give some relations among the endograph metric, the sendograph metric,?the supremum metric and the dp* metric. On the basis of the above results,?we present the characterizations of total boundedness, relative compactness?and compactness in the space of compact positive α-cuts fuzzy sets equipped?with the endograph metric, and in the space of compact support fuzzy sets?equipped with the sendograph metric, respectively. Furthermore, we give?completions of these metric spaces, respectively.

submitted time 2022-06-25 Hits19767Downloads1141 Comment 0

2. chinaXiv:202206.00173 [pdf]

中国SKA区域中心原型系统 -- 软件平台

劳保强; 张迎康; 安涛; 徐志骏; 郭绍光; 伍筱聪; 吕唯佳
Subjects: Astronomy >> Astronomical Instruments and Techniques

平方公里阵列(Square Kilometre Array, SKA)射电望远镜将在多个科学方向取得革命性的突破, 而SKA软件系统是影响科学产品的关键因素之一. SKA区域中心是天文学家进行SKA数据分析、科学研究和学术交流的平台. 处理SKA科学数据的软件环境需要具备通用性、灵活性和高适应性. 中国科学家已经建成了中国SKA区域中心原型机, 部署了被大型超级计算机广泛使用的作业调度系统, 并安装了能够处理当前主流射电望远镜观测数据的天文软件, 还部署了多个科学数据处理流水线, 以方便不同科学方向的观测数据的自动化并行处理. 本文介绍了中国SKA区域中心原型机的软件平台和处理SKA先导望远镜数据的流水线, 包括低频连续谱成像管线、谱线成像管线、以及甚长基线干涉测量数据处理管线. 国内外用户已经基于该平台成功开展了SKA相关科学研究. 该平台的建设和运行为未来全面建设中国SKA区域中心提供了宝贵的实践经验.

submitted time 2022-06-25 Hits109Downloads25 Comment 0

3. chinaXiv:202105.00070 [pdf]

Copula熵:理论和应用

马健
Subjects: Statistics >> Mathematical Statistics
Subjects: Mathematics >> Statistics and Probability
Subjects: Computer Science >> Computer Application Technology
Subjects: Information Science and Systems Science >> Basic Disciplines of Information Science and Systems Science

统计独立性是统计学和机器学习领域的基础性概念,如何表示和度量统计独立性是该领域的基本问题。Copula理论提供了统计相关关系表示的理论工具,而Copula熵理论则给出了度量统计独立性的概念工具。本文综述了Copula熵的理论和应用,概述了其基本概念定义、定理和性质,以及估计方法。介绍了Copula熵研究的最新进展,包括其在统计学的六个基本问题(结构学习、关联发现、变量选择、因果发现、域自适应和正态性检验等)上的理论应用。讨论了前四个理论应用之间的关系,以及其对应的深层次的相关性和因果性概念之间的联系,并将Copula熵的(条件)独立性度量框架与基于核函数和距离相关的同类框架进行了对比。简述了Copula熵在理论物理学、理论化学、化学信息学、水文学、环境气象学、生态学、动物形态学、农学、认知神经学、运动神经学、计算神经学、系统生物学、生物信息学、临床诊断学、老年医学、精神病学、公共卫生学、经济政策学、社会学、政治学,以及能源工程、土木工程、制造工程、可靠性工程、航空航天、通信工程、测绘工程和金融工程等领域的实际应用。

submitted time 2022-06-23 Hits37423Downloads4264 Comment 0

4. chinaXiv:202101.00003 [pdf]

On dark matter

Xian-Qiao Yu
Subjects: Physics >> The Physics of Elementary Particles and Fields

In this article, I shall propose an enlightening view on the origin of dark matter abundance, in which I introduce a neutral primordial field, which is a new field beyond the standard model, the mass of the primordial field is confined in the vicinity of neutrino mass (or 1-2 orders of magnitude different from the neutrino mass). All the standard model elementary particles are produced spontaneously from this field in the Big Bang epoch of the universe and then these produced elementary particles decayed or annihilated in the well-known standard model interactions. The relic of the primordial field appears in a form of vacuum energy can not only give naturally the correct abundance of dark matter in the present universe, but provide a natural solution to the cosmological constant problem as well. We find that the conventional methods of detecting dark matter either fail or have great difficulties to detect the remaining vacuum energy of the primordial field, and how to confirm the existence of the remaining energy of the universe's original energy in experiment is still an open problem.

submitted time 2022-06-21 Hits22008Downloads1601 Comment 0

5. chinaXiv:202110.00083 [pdf]

具有Lp度量的模糊集空间的性质

黄欢
Subjects: Mathematics >> Mathematics (General)

In this paper, we discuss the properties of  the spaces of fuzzy sets in a metric space with $L_p$-type $d_p$ metrics, $p\geq 1$. Firstly, we give the characterizations of compactness in fuzzy set space with $d_p$ metrics. Then we present the completions of fuzzy set spaces with $d_p$ metrics.
The $d_p$ metrics are well-defined if and only if a function induced by the Hausdorff metric is measurable. In this paper, we give some fundamental conclusions on the measurability of this function. This paper was submitted to Fuzzy Sets and Systems on 2022.05.06.

submitted time 2022-06-20 Hits8941Downloads777 Comment 0

6. chinaXiv:202206.00142 [pdf]

我国数字乡村政策的多级联动协同研究

吴江; 吴瑾; 段尧清
Subjects: Library Science,Information Science >> Information Science

[目的/意义]央地数字乡村政策协同对于政策落实并发挥最优政策效果,使数字乡村政策成为农业升级转型、农村经济发展中的强大助力具有重要意义。[方法/过程]本文利用2018-2021年的中央数字乡村政策和四大地区数字乡村政策样本数据,采用熵值法和耦合协调模型对中央和地方数字乡村政策之间的耦合协调度进行定量测度,在此基础上利用地理探测器模型进行单因子探测和多因子交互探测,分析各政策工具指标对央地政策协同水平的影响程度,探究政策间的多级联动效应。[结果/结论]四地区间央地政策总体协同水平不断优化,不同政策工具协同水平发展不均衡,协同水平区域差异趋于强化;各影响因素中科技创新政策是中央数字乡村政策与地方数字乡村政策协调发展的主要驱动力,且各影响因素间的两两交互作用效果强于单个影响因素。

submitted time 2022-06-14 Hits1636Downloads197 Comment 0

7. chinaXiv:202205.00179 [pdf]

关于信息容量的研究

许建峰
Subjects: Information Science and Systems Science >> Basic Disciplines of Information Science and Systems Science

[目的] 分析基于信息六元组模型的信息容量定义和性质,提出信息与物质、能量和时间的关系公式,为信息科学特别是量子信息科技应用提供理论参照。

[方法] 基于客观信息论提出的信息六元组模型,结合量子信息理论,通过严格的数学公理化方法,研究了多种组合条件下的信息容量效应,推导了信息容量与质量、能量和时间的关系。

[结果] 证明了利用信息熵定义信息容量仅仅是客观信息论所定义信息容量的一种特例,估算了单个量子载体所能承载的信息容量,推导给出信息与物质、能量和时间的关系公式,并以此计算和分析了迄今为止宇宙可能承载的信息容量。

[局限] 相关理论方法需要在物理学实证研究和复杂信息系统科学应用中得到验证。

[结论] 客观信息论的信息容量内涵能够较为深刻和准确地揭示客观世界物质、能量、和信息三大组成要素之间的相互关系,具有很好的普适意义和应用前景。

submitted time 2022-06-13 Hits717Downloads301 Comment 0

8. chinaXiv:202206.00038 [pdf]

相对性原理中的基础物理

陈驰一
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.
Subjects: Physics >> Geophysics, Astronomy, and Astrophysics

本文研究了质点动力学的相对性原理的物理逻辑。 通过对动力学中因果关系的分析,找到了牛顿力学中存在惯性力和惯性系问题的根源,发现在牛顿第二定律的形式体系中忽略了考虑参考物的因果对应。 参考系的动力学的特性应归因于参考物。 由此,参考物和被考察对象应被置于完全平等的地位。 因此,本文介绍了一个新的不受惯性系影响、并在所有平动参考系中都能直接适用的质点动力学的新方程。 对于旋转参考系,一方面由于前面已经揭示了惯性力的性质,即作用在参考物上的经过质量比加权后的真实受力。 因此,引力的物理效应已经明确不等同于惯性力的物理效应。 另一方面,根据因果对应的精神,动力学的相对性要拓展到旋转参考系,就要确定旋转参考系的物理,进一步则必须包含确定该参考系的至少四个不共面的参考物体的动力学性质。 因此,从数学上讲,还没有办法统一构建成一个简明的公式。 正是基于这两方面基础物理的考量,本文指出当前的任何广义相对性原理都是缺乏足够依据的。而对动力学的相对性原理进行拓展的关键是保证动力学方程两边的参考物的因果对应。

submitted time 2022-06-08 Hits879Downloads350 Comment 0

9. chinaXiv:202204.00030 [pdf]

国际科研数据政策导向解析

秦顺; 戴柏清
Subjects: Library Science,Information Science >> Library Science

[目的/意义]剖析国际科研数据政策的导向及其特征,为我国完善科研数据政策保障体系、优化科研数据管理与共享工作提供重要依据。[方法/过程]采用案例分析、文献调研方法归纳出国际科研数据政策的“整合DLC-SH”和“机器可操作”两种导向,并使用模本法分析、验证两种导向的异同。[结果/结论]“整合DLC-SH”导向秉持科研数据管理与共享整体观,遵循“组织管理-业务流程”基本框架,目的在于构建全球协同式数据治理方略;“机器可操作”导向提供依次递进的指导性原则,重视数据基础设施的辅助作用,目的在于实现“数据互联网”全球布局。两种导向在理论基础、核心组件和服务对象上存在不同,但在基础环境、实现途径和最终目标上基本一致,且两种导向的相互融合成为现阶段的主流趋势。建议我国强化政策的导向功用,融入国际工作体系;重塑工作机制与流程,完善数据治理格局;“人文与技术”相结合,构建“人机协同”生态。

submitted time 2022-06-06 Hits5357Downloads423 Comment 0

10. chinaXiv:202203.00067 [pdf]

Study on laser shocking of melt pool in Laser Additive Manufacturing of FeCoCrNi High-Entropy Alloys

Heng Lu; Xiaohan Zhang; Jian Liu ; Shusen Zhao; Xuechun Lin; Hui Li; Yaowu Hu
Subjects: Mechanical Engineering >> Mechanical Manufacture and Automation

With growing interest in Laser Additive Manufacturing (LAM) of High-entropy alloys (HEAs) during most recent years, the design of compositional elements and process strategies are primary methods to overcome undesirable microstructures and defects. Here we propose a new approach, a novel real-time Laser Shocking of Melt Pool (LSMP), to obtain melt pool modifications for yielding HEAs with desired characteristics. LSMP utilizes a pulsed laser shocking a liquid melt pool caused by a continuous wave laser, enabling non-destructive and real-time modulations for high-performance HEAs. The numerical simulation reveals the convection mechanism of the melt pool in the LSMP process, and the intervention of the pulsed laser promotes melt pool flow type to convert the Marangoni effect into a multi-convective ring, which accelerates melt pool flow and inhibits columnar crystal growth. Experimental results show the evolution law of the microstructure in the LSMP process. The microstructure of CrFeCoNi HEAs undergoes a Columnar-Equiaxed Transition (CET), and higher hardness is obtained. Laser shock is demonstrated to be an effective in-situ modulative tool for controlled additive manufacturing.

submitted time 2022-05-31 Hits1293Downloads437 Comment 0

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