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A New Version of Unified Field Theory—Stochastic Quantum Space Theory on Particle Physics and Cosmology 被引量:3
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作者 Zhi-Yuan Shen 《Journal of Modern Physics》 2013年第10期1213-1380,共168页
Stochastic Quantum Space (SQS) theory is a new version of unified field theory based on three fundamental postulations: Gaussian Probability Postulation, Prime Numbers Postulation, Vacuon Postulation. It build a frame... Stochastic Quantum Space (SQS) theory is a new version of unified field theory based on three fundamental postulations: Gaussian Probability Postulation, Prime Numbers Postulation, Vacuon Postulation. It build a framework with theoretical results agree with many experimental data well. For more information, please refer to the PDF. 展开更多
关键词 Unified Field THEORY space Structure Elementary Particles Gaussian Probability Prime Numbers SPORADIC Groups GUT DARK Matter DARK Energy Cosmos INFLATON MULTIVERSE Anthropic Principle General Relativity Primary Basic Equations
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基于CiteSpace可视化分析微囊藻毒素的研究进展
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作者 叶鸿雁 赵梓含 +2 位作者 刘春晖 岳士忠 王瑞萍 《中国农学通报》 2024年第25期81-88,共8页
为探究微囊藻毒素(MCs)研究领域的知识主题演化历程及研究热点,以中国知网(CNKI)中文核心期刊为数据来源,基于CiteSpace软件对MCs的研究动态进行文献计量分析。从年度发文量来看,MCs的研究受到学者大量、持续的关注,研究论文多发表于环... 为探究微囊藻毒素(MCs)研究领域的知识主题演化历程及研究热点,以中国知网(CNKI)中文核心期刊为数据来源,基于CiteSpace软件对MCs的研究动态进行文献计量分析。从年度发文量来看,MCs的研究受到学者大量、持续的关注,研究论文多发表于环境化学、生物学和生态学等领域的期刊,其中《水生生物学报》为载文量最多的期刊。关键词分析表明,MCs研究涉及内容较广,包括MCs毒性、检测、降解和时空分布等方面,其中MCs的生物降解及其毒性效应是研究的热点,MCs对草鱼器官及基因表达的影响是研究的前沿领域。MCs相关研究可分为3个阶段,1993—1999年研究处于初级阶段,以MCs的分离纯化、对肝脏的毒性效应和饮用水中MCs浓度研究为主;2000—2011年该领域研究热度提升,并呈现出多个研究方向,其中以MCs的生物降解和检测为主,并对MCs的毒性效应及环境分布相关领域进行了拓展性研究;2012—2021年继续对MCs含量的检测及其毒性效应进行深入研究。利用基因工程技术构建高效表达MCs降解基因的工程菌或建立稳定性好且降解效率高的微生物群落,研发加快生物降解的催化剂,研究环境相关浓度MCs复合污染的生态毒理效应及其作用机制是今后重要的研究方向。 展开更多
关键词 Cite space
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Einstein’s General Relativity and Pure Gravity in a Cosserat and De Sitter-Witten Spacetime Setting as the Explanation of Dark Energy and Cosmic Accelerated Expansion
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第2期332-339,共8页
Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 k... Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 killing vector fields corresponding to Witten’s five Branes model in eleven dimensional M-theory we reason that 504 of the 528 are essentially the components of the relevant killing-Yano tensor. In turn this tensor is related to hidden symmetries and torsional coupled stresses of the Cosserat micro-polar space as well as the Einstein-Cartan connection. Proceeding in this way the dark energy density is found to be that of Einstein’s maximal energy mc2 where m is the mass and c is the speed of light multiplied with a Lorentz factor equal to the ratio of the 504 killing-Yano tensor and the 528 states maximally symmetric space. Thus we have E (dark) = mc2 (504/528) = mc2 (21/22) which is about 95.5% of the total maximal energy density in astounding agreement with COBE, WMAP and Planck cosmological measurements as well as the type 1a supernova analysis. Finally theory and results are validated via a related theory based on the degrees of freedom of pure gravity, the theory of nonlocal elasticity as well as ‘t Hooft-Veltman renormalization method. 展开更多
关键词 General RELATIVITY COSSERAT Micro-Polar space Dark Energy Teleparellelism Wittens M-THEORY De Sitter spaceTIME Killing-Yano Tensor Einstein-Cartan RELATIVITY PURE GRAVITY Kaluza-Klein Theory Nonlocal Elasticity 't Hooft-Veltman Renormalization
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Modeling and Simulation Study of Space Data Link Protocol
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作者 Ismail Hababeh Rizik M. H. Al-Sayyed +2 位作者 Ja’far Alqatawna Yousef Majdalawi Marwan Nabelsi 《International Journal of Communications, Network and System Sciences》 2014年第10期440-452,共13页
This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). ... This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis. 展开更多
关键词 Consultative COMMITTEE for space DATA Systems Standards space DATA Link PROTOCOL Mean END-TO-END Packet Delay Maximum Achievable Application Layer Throughput Normalized PROTOCOL OVERHEAD Telecommand spacecrafts space Instruments
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Deciphering of Space Images of the Inder Salt-Dome Upland in ENVI 4.7 Program
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作者 K. M. Akhmedenov A. G. Koshym R. Z. Zhumabekova 《International Journal of Geosciences》 2014年第3期286-295,共10页
Space images play an important role in the Earth study as they bring the main information received from the Space Flyer Units (SFU) to help researchers. Space images’ deciphering gives the opportunity to study the te... Space images play an important role in the Earth study as they bring the main information received from the Space Flyer Units (SFU) to help researchers. Space images’ deciphering gives the opportunity to study the territory and to plot different maps. On the basis of the space image obtained from Landsat 5TM (30 m resolution, 01.09.2012 year), we managed to get a picture of the modern relief of the northern part of Inder lake. When comparing the space image with topographic maps of 1985, we succeeded to identify the dynamics of landforms change on the studied area, what has been shown on the drawn map of the relief of the Inder salt dome uplift. 14 classes, corresponding to a particular type of terrain or to a landscape complex, have been distinguished on the studied area. Inder salt dome uplift is a paradynamic conjugation, consisting of highly karsted Inder Mountains corresponding to large diapir uplift, and of the Inder Lake having a large ellipsoidal shape. Geomorphologically, the investigated territory is located on the left bank of Zhaiyk River, and presents a salt dome uplift in the form of a plateau-like hill raised above the surrounding surface from 12 to 40 m. The maximum height reaches 42.5 m (g. Suatbaytau). The crest of the Inder salt dome is composed of Low Permian sediments (rock salt with anhydrite, potassiummagnesium salts), and has an area of about 210 km2. Inder lake’s basin is represented by a tectonic depression, which is the local basis of erosion and is a drainage place of the Inder uplift karstic water. The lake area is 150 km2. Depending on the climatic conditions, the water level can vary. 展开更多
关键词 space Image Inder Salt-Dome Uplift KARST RELIEF Exogenous PROCESSES KARST PROCESSES RELIEF Shapes Basis of Erosion Automated Deciphering Vector Layer Objects Classification Object Classes Landscapes Complex Mapping
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Pinched Material Einstein Space-Time Produces Accelerated Cosmic Expansion
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作者 M. S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第1期80-90,共11页
An instructive analogy between the deformation of a pinched elastic cylindrical shell and the anti-gravity behind accelerated cosmic expansion is established. Subsequently the entire model is interpreted in terms of a... An instructive analogy between the deformation of a pinched elastic cylindrical shell and the anti-gravity behind accelerated cosmic expansion is established. Subsequently the entire model is interpreted in terms of a hyperbolic fractal Rindler space-time leading to the same robust results regarding real energy and dark energy being 4.5% and 95.5% respectively in full agreement with all recent cosmological measurements. 展开更多
关键词 Dark Energy Rindler space-TIME CARTAN Torsion Pinched Elastic Shells Negative Gravity COSMIC ACCELERATED EXPANSION Fractal space-TIME Topological Defects Hardys Quantum Entanglement Hawkings Radiation COSSERAT Elasticity
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 Linear Forms Dual spaces Frechet spaces Partial Derivatives DISTRIBUTIONS Topological Structure Weak Topology Strong Topology
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THREE KINDS OF DENTABILITIES IN BANACH SPACES AND THEIR APPLICATIONS
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作者 张子厚 周晶 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期445-454,共10页
In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting p... In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting point of a set.These are the generalizations of the weak^(*)denting point of a set in a dual Banach space.By use of the weak^(*)-weak denting point,we characterize the very smooth space,the point of weak^(*)-weak continuity,and the extreme point of a unit ball in a dual Banach space.Meanwhile,we also characterize an approximatively weak compact Chebyshev set in dual Banach spaces.Moreover,we define the nearly weak dentability in Banach spaces,which is a generalization of near dentability.We prove the necessary and sufficient conditions of the reflexivity by nearly weak dentability.We also obtain that nearly weak dentability is equivalent to both the approximatively weak compactness of Banach spaces and the w-strong proximinality of every closed convex subset of Banach spaces. 展开更多
关键词 weak^(%MUL%)-weak denting point nearly weak dentability very smooth space point of weak^(%MUL%)-weak continuity extreme point approximatively weak compactness w-strong proximinality REFLEXIVITY
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A review and research on comprehensive characterization of microscopic shale gas reservoir space 被引量:5
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作者 Yu-ru Yang Xiao-chen Liu +12 位作者 Hui Zhang Gang-yi Zhai Jiao-dong Zhang Zhi-fang Hu Shu-jing Bao Cong Zhang Xiang-hua Wang Xiao Yang Zheng-zhuang Liu Ting Xie Juan Chen Liyu Fang Li-juan Qin 《China Geology》 2019年第4期541-556,共16页
In this paper,substantial domestic and foreign research results of microscopic shale reservoir space were systemically reviewed,the research history consisting of simple observation and qualitative classification,quan... In this paper,substantial domestic and foreign research results of microscopic shale reservoir space were systemically reviewed,the research history consisting of simple observation and qualitative classification,quantitative research,the combination of qualitative and quantitative research successively as well as the characteristics of each research stage were summarized.In addition,the current problems existing in the characterization methods of shale reservoir space were also analyzed.Furthermore,based on massive actual detection of typical core samples obtained from more than 50 global shale gas wells and relevant practical experience,a comprehensive characterization method of combining qualitative with the semiquantitative characterization was put forward.In detail,the indicators of the qualitative characterization include pore combination type and organic-matter microscopic morphology type,while the core elements of the semi-quantitative characterization include the percentage of the organic-matter area and the plane porosity of the pores of different types.Based on the reference of the naming and classification of rocks,the three-end-member diagram method was used to characterize microscopic shale reservoir space.This is achieved by plotting the three end-member diagram of 3 kinds of first-order critical reservoir spaces,i.e.,organic-matter pores,matrix pores,and micro-fractures,in order to intuitively present the features of the microscopic pore combination.Meanwhile,statistic histograms of organic-matter microscopic morphology type and the plane porosity of different types of pores were adopted to characterize the development degree of second-order pores quantitatively.By this comprehensive characterization method,the importance of both pore combination and the microscopic morphology of organic matter were emphasized,revealing the control of organic-matter microscopic morphology over the organic-matter pores.What is more,high-resolution FE-SEM was adopted to obtain semi-quantitative statistics results.In this way,the features of pore development and pore combination were quantified,not only reflecting the types and storage capacity of the microscopic shale reservoir space,but also presenting the hydrocarbongenerating potential of organic matter in shale.Therefore,the results of this research are capable of providing in-depth microscopic information for the assessment and exploration and development of shale gas resources. 展开更多
关键词 SHALE SHALE gas Reservoir space RESEARCH status Types of PORE COMBINATIONS Oil-gas exploration engineering Longmaxi FORMATION Niutitang FORMATION Shahejie FORMATION Yanchang FORMATION China USA
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Improving landscape Characteristics in Port Said’s El Sallam Garden via Observational and Space Syntax Analysis
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作者 Amr Ali Bayoumi 《Journal of Civil Engineering and Architecture》 2024年第3期101-111,共11页
This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be use... This paper provides a comprehensive examination of El Sallam Garden in Port Said City,concentrating on its landscape characteristics and potential for design enhancement.This study looks at how space syntax can be used to assess the impact of a tree planting design’s spatial configuration on an urban park’s visual fields.Trees play an important role in determining the spatial characteristics of an outdoor space.According to space syntax theory,an urban area is a collection of connected spaces that can be represented by a matrix of quantitative properties known as syntactic measures.Computer simulations can be used to measure the quantitative properties of these matrices.This study uses space syntax techniques to assess how tree configurations and garden area which can affect the social structures of small-scale gardens in Port Said.It also looks at how these techniques can be used to predict the social structures of four garden zones in El Sallam Garden.The study includes an observational and space syntax study through comparative analysis of four garden zones in El Sallam garden.The results of the study show that the area and planting configurations of the garden had a significant effect on the syntactic social and visual measures of the urban garden.The conclusions and recommendations can be a useful tool for landscape architects,urban planners,and legislators who want to enhance public areas and encourage social interaction in urban settings. 展开更多
关键词 VGA(visibility graph analysis) agent simulation space syntax minimal paths garden landscape design behavioral mapping gate count
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Prescribed performance neural control to guarantee tracking quality for near space kinetic kill vehicle 被引量:5
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作者 ZHANG Tao LI Jiong +2 位作者 LI Weimin WANG Huaji LEI Humin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期573-586,共14页
A prescribed performance neural controller to guarantee tracking quality is addressed for the near space kinetic kill vehicle (NSKKV) to meet the state constraints caused by side window detection. Different from the t... A prescribed performance neural controller to guarantee tracking quality is addressed for the near space kinetic kill vehicle (NSKKV) to meet the state constraints caused by side window detection. Different from the traditional prescribed performance control in which the shape of the performance function is constant, this paper exploits new performance functions which can change the shape of their function according to different symbols of initial errors and can ensure the error convergence with a small overshoot. The neural backstepping control and the minimal learning parameters (MLP) technology are employed for exploring a prescribed performance controller (PPC) that provides robust tracking attitude reference trajectories. The highlight is that the transient performance of tracking errors is satisfactory and the computational load of neural approximation is low. The pseudo rate (PSR) modulator is used to shape the continuous control command to pulse or on-off signals to meet the requirements of the thruster. Numerical simulations show that the proposed method can achieve state constraints, pseudo-linear operation and high accuracy. 展开更多
关键词 PRESCRIBED PERFORMANCE control near space kinetic KILL vehicle (NSKKV) neural approximation minimal learning parameter (MLP) pseudo rate (PSR) MODULATOR
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3D MERGE与3D SPACE STIR序列在腰椎间盘突出症检查中的应用比较 被引量:1
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作者 李兰 殷小丹 +2 位作者 李旭雪 吴海燕 张滔 《中国医学物理学杂志》 CSCD 2024年第1期27-31,共5页
目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,... 目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。 展开更多
关键词 3D MERGE 3D space STIR
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Analyzing Whether a Space Shuttle Can Withstand a Perpendicular Launch from Mars
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作者 Mayank Banerjee 《Natural Science》 2023年第10期257-262,共6页
In the near future, humans will go to Mars. During these interplanetary journeys, astronaut safety will be paramount. This study aims to determine whether the astronauts will be able to launch safely from Mars in a sp... In the near future, humans will go to Mars. During these interplanetary journeys, astronaut safety will be paramount. This study aims to determine whether the astronauts will be able to launch safely from Mars in a space shuttle taking off perpendicularly. This study used kinematics along with equations for calculating atmospheric density and total force on the spacecraft to evaluate these values for each atmospheric layer. Approximations were made for the spacecraft’s dimensions to find the cross-sectional front-view area of the spacecraft and the drag coefficient where verifiable data was unavailable. Although there is data for the dimensions of the spacecraft’s front view, there isn’t any on its area. The total force was found to be significantly lower than 3Gs which ensures a safe take-off for the astronauts and reduces manufacturing costs for assembling new rockets. 展开更多
关键词 space Shuttle spacecraft MARS ROCKET Physics Atmosphere Drag Gravity ASTRONAUT Force THRUST Fuel
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E-Infinity Dualities, Discontinuous Spacetimes, Xonic Quantum Physics and the Decisive Experiment 被引量:2
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作者 Jean-Paul Auffray 《Journal of Modern Physics》 2014年第15期1427-1436,共10页
Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Nas... Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Naschie, this paper explores the deep implications of some of the dualities Dr El Naschie has identified and analyzed in his exposes, connecting them with our own Xonic Quantum Physics (XQP) which places dynamical action rather than spacetime and energy at the core of the System of the World. 展开更多
关键词 E-INFINITY El Naschie space Time spaceTIME Topology CANTOR Sets Energy Xon Xonic Quantum Physics PLANCK Scale Dirac Electron
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AN INTEGRATION METHOD WITH FITTING CUBIC SPLINE FUNCTIONS TO A NUMERICAL MODEL OF 2ND-ORDER SPACE-TIME DIFFERENTIAL REMAINDER——FOR AN IDEAL GLOBAL SIMULATION CASE WITH PRIMITIVE ATMOSPHERIC EQUATIONS
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作者 辜旭赞 张兵 王明欢 《Journal of Tropical Meteorology》 SCIE 2013年第4期388-396,共9页
In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubi... In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubic spline numerical model(Spline Model for short),which is with a quasi-Lagrangian time-split integration scheme of fitting cubic spline/bicubic surface to all physical variable fields in the atmospheric equations on spherical discrete latitude-longitude mesh.A new algorithm of"fitting cubic spline—time step integration—fitting cubic spline—……"is developed to determine their first-and2nd-order derivatives and their upstream points for time discrete integral to the governing equations in Spline Model.And the cubic spline function and its mathematical polarities are also discussed to understand the Spline Model’s mathematical foundation of numerical analysis.It is pointed out that the Spline Model has mathematical laws of"convergence"of the cubic spline functions contracting to the original functions as well as its 1st-order and 2nd-order derivatives.The"optimality"of the 2nd-order derivative of the cubic spline functions is optimal approximation to that of the original functions.In addition,a Hermite bicubic patch is equivalent to operate on a grid for a 2nd-order derivative variable field.Besides,the slopes and curvatures of a central difference are identified respectively,with a smoothing coefficient of 1/3,three-point smoothing of that of a cubic spline.Then the slopes and curvatures of a central difference are calculated from the smoothing coefficient 1/3 and three-point smoothing of that of a cubic spline,respectively.Furthermore,a global simulation case of adiabatic,non-frictional and"incompressible"model atmosphere is shown with the quasi-Lagrangian time integration by using a global Spline Model,whose initial condition comes from the NCEP reanalysis data,along with quasi-uniform latitude-longitude grids and the so-called"shallow atmosphere"Navier-Stokes primitive equations in the spherical coordinates.The Spline Model,which adopted the Navier-Stokes primitive equations and quasi-Lagrangian time-split integration scheme,provides an initial ideal case of global atmospheric circulation.In addition,considering the essentially non-linear atmospheric motions,the Spline Model could judge reasonably well simple points of any smoothed variable field according to its fitting spline curvatures that must conform to its physical interpretation. 展开更多
关键词 NUMERICAL forecast and NUMERICAL SIMULATION 2nd-order space-TIME differential REMAINDER NUMERICAL model cubic spline functions Navier-Stokes PRIMITIVE EQUATIONS quasi-Lagrangian time-split integration scheme global SIMULATION case
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Lorentz Transform in Multi-Dimensional Space
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作者 I. A. Urusovskii 《Journal of Modern Physics》 2012年第11期1749-1756,共8页
It is shown that in Euclidean space with any number of spatial dimensions more than three, the Lorentz transform holds true if the proper time of each elementary particle is proportional to the length of its path in t... It is shown that in Euclidean space with any number of spatial dimensions more than three, the Lorentz transform holds true if the proper time of each elementary particle is proportional to the length of its path in the extra-dimensional subspace, and all elementary particles move at the speed of light in the complete space. The six-dimensional treatment of the Coulomb force of interaction between two charges is given. The electric force is due to the motion of charges in the extra-dimensional subspace and is equal to the corresponding Lorentz force. 展开更多
关键词 LORENTZ Transform Euclidean Multi-Dimensional space COMPTON Wave Length De BROGLIE Waves SPIN and Isotopic SPIN HEISENBERG Uncertainty CPT Symmetry COULOMB Force
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The Basics of Flat Space Cosmology
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作者 Eugene Terry Tatum U. V. S. Seshavatharam S. Lakshminarayana 《International Journal of Astronomy and Astrophysics》 2015年第2期116-124,共9页
We present a new model of cosmology which appears to show great promise. Our flat space cosmology model, using only four basic and reasonable assumptions, derives highly accurate Hubble parameter H0, Hubble radius R0 ... We present a new model of cosmology which appears to show great promise. Our flat space cosmology model, using only four basic and reasonable assumptions, derives highly accurate Hubble parameter H0, Hubble radius R0 and total mass M0 values for our observable universe. Our model derives a current Hubble parameter of , in excellent agreement with the newly reported (lower limit) results of the 2015 Planck Survey. Remarkably, all of these derivations can be made with only these basic assumptions and the current CMB radiation temperature . The thermodynamic equations we have generated follow Hawking’s black hole temperature formula. We have also derived a variety of other useful cosmological formulae. These include angular velocity and other rotational formulae. A particularly useful hyperbolic equation, , has been derived, which appears to be an excellent fit for the Planck scale as well as the current observable universe scale. Using the flat space Minkowski relativistic formula for Doppler effect, and a formula for staging our cosmological model according to its average mass-energy density at every Hubble time (universal age) in its expansion, a persuasive argument can be made that the observable phenomena attributed to dark energy are actually manifestations of Doppler and gravitational redshift. Finally, a theory of cosmic inflation becomes completely unnecessary because our flat space cosmology model is always at critical density. 展开更多
关键词 FLAT space COSMOLOGY Cosmic Inflation Dark Energy Hubble Parameter Critical Density Angular Velocity LIGHT SPEED Expansion LIGHT SPEED Rotation Redshift Universe CMBR
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Recent Progress in Space Science and Applications on Chinese Space Station in 2022–2024
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作者 GU Yidong GAO Ming +4 位作者 ZHAO Guangheng WANG Qiang LYU Congmin ZHONG Hongen LIU Guoning 《空间科学学报》 CAS CSCD 北大核心 2024年第4期607-621,共15页
Chinese Space Station(CSS)has been fully deployed by the end of 2022,and the facility has entered into the application and development phase.It has conducted scientific research projects in various fields,such as spac... Chinese Space Station(CSS)has been fully deployed by the end of 2022,and the facility has entered into the application and development phase.It has conducted scientific research projects in various fields,such as space life science and biotechnology,space materials science,microgravity fundamental physics,fluid physics,combustion science,space new technologies,and applications.In this review,we introduce the progress of CSS development and provide an overview of the research conducted in Chinese Space Station and the recent scientific findings in several typical research fields.Such compelling findings mainly concern the rapid solidification of ultra-high temperature alloy melts,dynamics of fluid transport in space,gravity scaling law of boiling heat transfer,vibration fluidization phenomenon of particulate matter,cold atom interferometer technology under high microgravity and related equivalence principle testing,the full life cycle of rice under microgravity and so forth.Furthermore,the planned scientific research and corresponding prospects of Chinese space station in the next few years are presented. 展开更多
关键词 Chinese space Station(CSS) space material science Micro-gravity fluid physics Fundamental physics space life sciences and biotechnology
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Design Strategy of Street Space Micro Renewal: A Case Study of Baihuazhou District of Nanchang City
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作者 WU Siyu 《Journal of Landscape Research》 2024年第4期39-43,共5页
Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street... Against the backdrop of incremental planning moving towards stock planning, strengtheningurban public space design to promote high-quality urban development has become a focus of attentionfor domestic scholars. Street is a linear element of urban public space, and it is of great significance forimproving the quality of urban public space by studying the micro renewal design strategy of street space.Based on the interpretation of two urban renewal cases, Wangjing Street in Beijing and Mengzhuiwan inChengdu, taking Baihuazhou area in Nanchang City as an example, this paper analyzes the main problemsin the current situation of street space in Baihuazhou area from three aspects: space use, traffic organization,and waterfront space creation, and explores the micro renewal design strategy of the street space. 展开更多
关键词 Nanchang City Baihuazhou Street space Micro renewal Old town Waterfront space
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Data Collection and Research on the Vitality of Public Space in Traditional Villages: A Case Study of Cuandixia Village
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作者 PAN Mingshuai LI Xiaomeng 《Journal of Landscape Research》 2024年第3期27-30,36,共5页
The optimization and renewal of rural space is the foundation for building livable,business friendly and harmonious countryside.Three types of data on the spatial vitality of traditional villages are collected and ana... The optimization and renewal of rural space is the foundation for building livable,business friendly and harmonious countryside.Three types of data on the spatial vitality of traditional villages are collected and analyzed.A street and alley axis map model is established using spatial syntax,and the degree of industry aggregation is quantified using POI data,and the results of syntactic calculation are validated with the help of popular review text preferences.Taking Cuandixia Village as an example,this paper found that its public space nodes have a pattern of one axis and scattered points;the street and alley space is well preserved but slightly lacking in transportation;the user group is single and the form is traditional.This paper could provide corresponding suggestions for stimulating the vitality of public spaces in traditional villages,in order to provide inspiration for the revitalization design of public spaces in traditional villages. 展开更多
关键词 Traditional villages space syntax Vitality of public spaces Cuandixia Village Public space of villages
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