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Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响
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作者 刘伟 倪木兰 《蚌埠医学院学报》 CAS 2024年第5期669-673,共5页
目的:探讨Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响。方法:选取急性脑梗死病人80例,随机分为对照组和观察组,各40例。对照组给予常规护理,观察组在常规护理基础上给予Three-talk决策模式(包括团队会谈、选... 目的:探讨Three-talk决策模式干预对急性脑梗死病人神经功能恢复和心理状态的影响。方法:选取急性脑梗死病人80例,随机分为对照组和观察组,各40例。对照组给予常规护理,观察组在常规护理基础上给予Three-talk决策模式(包括团队会谈、选择会谈、决策会谈)干预,比较2组病人干预前和干预1个月后的负性情绪、肢体肌力、运动功能、吞咽功能和自我护理能力(ESEA)评分。结果:干预前,2组病人焦虑、抑郁、肢体肌力、运动功能、吞咽功能和ESEA评分差异均无统计学意义(P>0.05);干预1个月后,观察组焦虑、抑郁和吞咽功能评分均明显低于对照组(P<0.01),肢体肌力、运动功能、ESEA评分均明显高于对照组(P<0.01)。结论:Three-talk决策模式干预有助于缓解急性脑梗死病人的焦虑、抑郁情绪,帮助病人实现肢体肌力、运动及吞咽功能的恢复,进而提高其自我护理能力。 展开更多
关键词 急性脑梗死 three-talk决策模式 负性情绪 肢体肌力 运动功能
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Attribute Reduction Method Based on Sequential Three-Branch Decision Model
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作者 Peiyu Su Fu Li 《Applied Mathematics》 2024年第4期257-266,共10页
Attribute reduction is a research hotspot in rough set theory. Traditional heuristic attribute reduction methods add the most important attribute to the decision attribute set each time, resulting in multiple redundan... Attribute reduction is a research hotspot in rough set theory. Traditional heuristic attribute reduction methods add the most important attribute to the decision attribute set each time, resulting in multiple redundant attribute calculations, high time consumption, and low reduction efficiency. In this paper, based on the idea of sequential three-branch decision classification domain, attributes are treated as objects of three-branch division, and attributes are divided into core attributes, relatively necessary attributes, and unnecessary attributes using attribute importance and thresholds. Core attributes are added to the decision attribute set, unnecessary attributes are rejected from being added, and relatively necessary attributes are repeatedly divided until the reduction result is obtained. Experiments were conducted on 8 groups of UCI datasets, and the results show that, compared to traditional reduction methods, the method proposed in this paper can effectively reduce time consumption while ensuring classification performance. 展开更多
关键词 Attribute Reduction three-Branch Decision Sequential three-Branch Decision
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Three-qubit海森堡XYZ各向异性自旋链系统QMA熵不确定度的量子调控
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作者 刘科洋 周清平 《原子与分子物理学报》 北大核心 2024年第6期109-116,共8页
本文研究了three-qubit海森堡XYZ各向异性自旋链系统各项参数和外加磁场对量子存储支撑(Quantum memory assisted,QMA)熵不确定度及其下限的调控行为,以及对被测系统与存储系统之间量子纠缠的影响.结果表明:增大系统的Dzyaloshinski-Mor... 本文研究了three-qubit海森堡XYZ各向异性自旋链系统各项参数和外加磁场对量子存储支撑(Quantum memory assisted,QMA)熵不确定度及其下限的调控行为,以及对被测系统与存储系统之间量子纠缠的影响.结果表明:增大系统的Dzyaloshinski-Moriya(DM)相互作用强度、降低系统温度、增大沿Z正方向磁场强度可以提高被测系统与存储系统之间的量子纠缠,降低系统QMA熵不确定度及其下限,被测系统与存储系统之间的量子纠缠与QMA熵不确定度及其下限呈类反相关. 展开更多
关键词 three-qubit海森堡XYZ各向异性自旋链 QMA熵不确定度 DM相互作用 平方负性纠缠
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Petrophysical Evaluation of Cape Three Points Reservoirs
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Larry Pax Chegbeleh 《International Journal of Geosciences》 CAS 2024年第2期162-179,共18页
The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and T... The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (WELL_1X, WELL_2X, and WELL_3X) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (WELL_1X, WELL_2X and WELL_3X) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells. 展开更多
关键词 Petrophysical Cape three Points RESERVOIRS
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Application of the “Three Threes” Method in Clinical Teaching of Internal Jugular Vein Puncture
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作者 Pengchao Cheng Wang Xi +3 位作者 Junnan Wang Jin Rao Yufeng Zhang Zhinong Wang 《Open Journal of Emergency Medicine》 2024年第1期10-17,共8页
Objective: To clarify the role of the “Three Threes” method in clinical teaching of internal jugular vein puncture and explore improvements in teaching methods. Methods: A doctor was assigned to the induction room o... Objective: To clarify the role of the “Three Threes” method in clinical teaching of internal jugular vein puncture and explore improvements in teaching methods. Methods: A doctor was assigned to the induction room of the Second Affiliated Hospital of Naval Medical University (Shanghai Changzheng Hospital) for two months. The time required for catheterization, the first puncture success rate, and occurrence of puncture-related complications were compared before and after learning the “Three Threes” method. Results: Using the “Three Threes” method reduced the catheterization time by 43%, increased the first puncture success rate by 17%, and led to fewer puncture-related complications. Conclusion: The application of the “Three Threes” method not only improves the success rate of internal jugular vein puncture but also reduces complications, making it easier for students to master the technique. 展开更多
关键词 Internal Jugular vein Puncture three threes” Method Deep Vein Catheterization Teaching Practice
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Design of a Three-Phase Grid Connector System Using Power Transfer from Park’s Transformation
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作者 Birtukan Yenealem Elias Mamushet 《Smart Grid and Renewable Energy》 2024年第5期123-138,共16页
Instabilities in grid-connected inverters can arise from a number of sources, including mismatched parameters, grid impedance, faults, and feedback delays. Park’s transformation provides accurate control over reactiv... Instabilities in grid-connected inverters can arise from a number of sources, including mismatched parameters, grid impedance, faults, and feedback delays. Park’s transformation provides accurate control over reactive and active (real) power. This enhances the overall efficiency of the system by enabling operators to control reactive power compensation and optimize energy flow. In dynamic settings, this guarantees greater system stability and faster response times. The current paper aims to improve the grid system by utilizing the dq0 controller. The current work focuses on the analysis based on simulations and theory, where the state space equation serves as the basis for dq-axis current decoupling. A MATLAB platform was used to simulate the complete system. TDH values of 2.45%, or less than 5%, in the given results are acceptable. The suggested controller was hence appropriate for grid system applications. 展开更多
关键词 Grid System INVERTER Optimization ENERGY three Phase
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Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients
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作者 Wangti Xie Yu Wu +11 位作者 Xiaoshan Cheng Jianbing Hu Fang Wen Jia Xiao Pan Luo Yuqi Su Xiang Yao Jianlong Fang Grong Dan Xianggan Huang Dunqian Liu Jie Weng 《Journal of Biosciences and Medicines》 2024年第7期325-336,共12页
Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lu... Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. . 展开更多
关键词 Pulmonary Nodules Elderly patients three-Dimensional (3D) Printed Coplanar Template (PCT) Core Needle Biopsy (CNB) Computed Tomography (CT)
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Numerical Study of a Three-Dimensional Laminar Flow in a Rectangular Channel with a 180-Degree Sharp Turn
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作者 Takashi Yoshida 《Open Journal of Fluid Dynamics》 2024年第3期147-162,共16页
This study presents a numerical analysis of three-dimensional steady laminar flow in a rectangular channel with a 180-degree sharp turn. The Navier-Stokes equations are solved by using finite difference method for Re ... This study presents a numerical analysis of three-dimensional steady laminar flow in a rectangular channel with a 180-degree sharp turn. The Navier-Stokes equations are solved by using finite difference method for Re = 900. Three-dimensional streamlines and limiting streamlines on wall surface are used to analyze the three-dimensional flow characteristics. Topological theory is applied to limiting streamlines on inner walls of the channel and two-dimensional streamlines at several cross sections. It is also shown that the flow impinges on the end wall of turn and the secondary flow is induced by the curvature in the sharp turn. 展开更多
关键词 180-Degree Sharp Turn Channel three Dimensional Steady Flow Limiting Streamline Topological Theory
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order three-Point Boundary Value Problem Sign-Changing Green’s Function Fixed Point Index Iterative Technique Monotone Positive Solution EXISTENCE
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Design and Realization of Block Level Augmented Reality Three-Dimensional Map
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作者 Dashuai Shang Chenguang Dai +1 位作者 Ying Yu Yabing Fan 《Journal of Computer and Communications》 2023年第6期113-121,共9页
In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those ... In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those provide references and ideas for the later large-scale production of augmented reality three-dimensional map. The augmented reality three-dimensional map is produced based on skyline software. Including the map browsing, measurement and analysis and so on, the basic function of three-dimensional map is realized. The special functional module including housing management, pipeline management and so on is developed combining the need of residential quarters development, that expands the application fields of augmented reality three-dimensional map. Those lay the groundwork for the application of augmented reality three-dimensional map. . 展开更多
关键词 Augmented Reality three-Dimensional Map Multi-Source Data Fusion three-Dimensional Analysis three-Dimensional Scene SKYLINE
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Three-Drug Therapies in Psychiatry in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”—D.D. 23 Luglio 2023, Tempo Ordinario (3.00 e 10.20)
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第8期2267-2308,共42页
The present paper aims at showing the possible adoption in Psychiatry of a general methodology finalized to prescribe the most appropriate Therapy based on the knowledge of its correlative effects in advance, instead ... The present paper aims at showing the possible adoption in Psychiatry of a general methodology finalized to prescribe the most appropriate Therapy based on the knowledge of its correlative effects in advance, instead of recognizing them ex post. The specific case here considered is the “bipolar disorder”, in which the adoption of three different drugs is the most common practice, although with a possible differentiation between the prescription in the morning and in the evening, respectively. Thus, the proposed methodology will consider the Ordinal Interactions between the various drugs by evaluating their combined effects, which will result as being not a simple additive “sum”, because they are evaluated on the basis of the Maximum Ordinality Principle (MOP) and, in addition, in Adherence to the Explicit Solution to the “Three-Body Problem”. In this way the Methodology here proposed is able to suggest how to account for the synergistic effects of the various drugs, especially when the latter are characterized by different concentrations and, at the same time, by generally different half-lives respectively. 展开更多
关键词 three-Drug Therapies Bipolar Disorder Psychiatric Therapies Maximum Ordinality Principle (MOP) three-Body Problem”
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Comparison of Pfizer/BioNTech BNT162b2 COVID-19 (Comirnaty) Vaccination Effects in Aged Adults with Special Consideration for the Effectiveness of the Three-Color iSpot in Assessing Immune Response
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作者 Stefanie Sonnleitner Sissy Therese Sonnleitner +1 位作者 Simone Obererlacher Gernot Walder 《Journal of Biosciences and Medicines》 CAS 2023年第5期111-123,共13页
Background: The roll-out of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was certainly among the fastest in medical history. Vaccination campaigns around the world began a year after t... Background: The roll-out of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was certainly among the fastest in medical history. Vaccination campaigns around the world began a year after the outbreak in 2019. When Austria started vaccinating the population in 2020, we took the opportunity to collect data from the first sets of patients receiving the vaccine in our study region of East Tyrol. Purpose: Many studies have been conducted examining the immunogenicity of the new vaccines using classic serological test methods in combination with an IFN-γ ELISpot. Undeniable disadvantages of using IFN-γ to characterize the status of the cellular immunity are that 1) being an acute phase cytokine, IFN-γ loses signal strength in the long run and 2) IFN-γ does not provide information about the involvement of T helper 2 (Th2) cells in the immune process. This implies that it can affect false negative data about the cell-mediated immune status. Method: Therefore, in addition to a chemiluminescent immunoassay and the enzymatic IFN-γ ELISpot, this study included a fluorescent ELISpot assay using precoated human SARS-CoV-2-specific IFN-γ/IL-2/IL-5 ELISpot kits to show a more holistic overview on the involvement of T helper 1 (Th1) cells as signal senders of IL-2 and Th2 cells as senders of IL-5. Results and Conclusion: Our study confirms good immunogenicity of Pfizer/BioNTech BNT162b2 COVID-19 (Comirnaty) with strong Th1 and vanishingly small Th2 participation. The fluorescent three color iSpot can improve the diagnostic results’ significance for the individual, especially when the infection has been longer in the past and the IFN-γ signal diminishes. 展开更多
关键词 three-Color iSpot Immune Response VACCINATION
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Purification of Moringa oleifera Leaves Protease by Three-Phase Partitioning and Investigation of Its Potential Antibacterial Activity
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作者 Adam Abdoulaye Agossou D. P. Noumavo +6 位作者 Durand Dah-Nouvlessounon Messan A. B. Ohin Hasan Bayraktar Farid T. Bade Honoré S. Bankole Lamine Baba-Moussa Farid Baba-Moussa 《American Journal of Plant Sciences》 CAS 2023年第1期64-76,共13页
One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for thei... One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for their purifications. As such, three-phase partitioning (TPP) was used to purify protease from moringa (Moringa oleifera). TPP is an emerging, promising, non-chromatographic and economical technology which is simple, quick, efficient and often one-step process for the separation and purification of bioactive molecules from natural sources. It involves the addition of salt (ammonium sulphate) to the crude extract followed by the addition of an organic solvent (butanol). The protein appears as an interfacial precipitate between upper organic solvent and lower aqueous phases. The various conditions such as ammonium sulphate, ratio of crude extract to t-butanol and pH which are required for attaining efficient purification of the protease fractions were optimized. Under optimized conditions, it was seen that, 35% of ammonium sulphate saturation with 1:0.75 ratio of crude extract to t-butanol at pH 7 gave 4.94-fold purification with 96.20% activity yield of protease in the middle phase of the TPP system. The purified enzyme from Moringa oleifera has no antimicrobial effect on the pathogenic bacteria tested. However, this purified enzyme, can be considered as a promising agent, cheap, and safe source which is suitable for using in various industries. 展开更多
关键词 three-Phase Partitioning Moringa oleifera PROTEASE Protein Purification ANTIMICROBIAL
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Stationary Measures of Three-State Quantum Walks with Defect on the One-Dimension Lattice
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作者 Jinling Gao Mingjun Zhang 《Open Journal of Applied Sciences》 CAS 2023年第4期473-482,共10页
In this paper, we focus on the space-inhomogeneous three-state on the one-dimension lattice, a one-phase model and a two-phase model include. By using the transfer matrices method by Endo et al., we calculate the stat... In this paper, we focus on the space-inhomogeneous three-state on the one-dimension lattice, a one-phase model and a two-phase model include. By using the transfer matrices method by Endo et al., we calculate the stationary measure for initial state concrete eigenvalue. Finally we found the transfer matrices method is more effective for the three-state quantum walks than the method obtained by Kawai et al. 展开更多
关键词 three-State Quantum Walks Stationary Measure One-Phase TWO-PHASE Transfer Matrices
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Solution to the “Three-Body Problem” in the Light of the Maximum Ordinality Principle, as a “Suggestion” for a Ri-Orientation of the Present Scientific Perspective in “Favor” of the “Irreducible Quality”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第1期209-259,共51页
This paper presents the Solution to the “Three-body Problem” in the Light of the Maximum Ordinality Principle. In the first part, however, it starts with the Solution to the Solar System, made up of “11 Bodies”. T... This paper presents the Solution to the “Three-body Problem” in the Light of the Maximum Ordinality Principle. In the first part, however, it starts with the Solution to the Solar System, made up of “11 Bodies”. This is because, in such a context, the “Three-body Problem” can be analyzed in its all descriptive possibilities. Nonetheless, the paper also presents the Solution to the “Three-body Problem” with reference to Systems totally independent from the Solar System, such as, for example, the “Triple Stars” and the “Triple Galaxies”. In this way, the paper offers a sufficiently complete framework concerning the Solution to the “Three-body Problem”, always in the Light of the Maximum Ordinality Principle, described in detail in Appendix A. 展开更多
关键词 three-Body Problem Light of the Maximum Ordinality Principle Solution to the Solar System
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Apparent Accelerated Expansion of the Three-Dimensional Spherical Universe Observed during Its Contraction Phase
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作者 Hitoshi Shibata Norio Ogata 《Journal of Modern Physics》 2023年第S1期1693-1702,共10页
In recent years, it has been thought that the expansion of the universe has begun to accelerate. However, there are other views against this. Here we propose a new theory based on the three-dimensional spherical (S<... In recent years, it has been thought that the expansion of the universe has begun to accelerate. However, there are other views against this. Here we propose a new theory based on the three-dimensional spherical (S<sup>3</sup>) universe wherein the same observations as the present universe can also be found by the accelerated contraction of the universe. According to our theory, the expansion velocity of the S<sup>3</sup> universe slowed down after the Big Bang, and all the kinetic energy was converted into potential energy to reach the great sphere. After that, accelerated contraction begins, and the universe finally converges to an original single point. In the S<sup>3</sup> universe, the passage of time (referred to as “proper time”) changes depending on its expansion velocity. The frequency of light emitted from celestial bodies is determined by their proper time on emission, and when the light is observed by observers having different proper time, a redshift or blueshift is observed. Observers in the expansion phase observe redshifts, because the proper time of the observer progresses faster than that of emitted light, but observers in the contraction phase observe an accelerated delay of the proper time, so the progress of the proper time is reversed based upon its order from nearby celestial bodies, a blueshift is observed, and its range of observable distance increases. The results of this early contraction phase are consistent with the observations of the current universe. In conclusion, the S<sup>3</sup> universe may be able to explain the geometrical structure of the current universe. 展开更多
关键词 three-Dimensional Universe Spherical Universe REDSHIFT Big Bang
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Generativity of Self-Organizing Processes and Their Correlative Description in Terms of a Formal Language of Meta-Ordinal Generative Nature, in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第10期3159-3202,共44页
The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be mode... The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be modeled using the Maximum Ordinality Principle and its associated formal language, known as the “Incipient” Differential Calculus (IDC). 展开更多
关键词 Maximum Ordinality Principle Solution to the three-Body Problem” Generativity of Self-Organizing Processes Formal Language of Ordinal Generativity Formal Language of Meta-Ordinal Generativity
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Correlation Analysis between the Evapotranspiration Quantity and Climatic Factors of Artificial Grassland in Three River Sources Areas 被引量:11
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作者 冯承彬 张耀生 +2 位作者 赵双喜 赵新全 米兆荣 《Agricultural Science & Technology》 CAS 2008年第5期13-18,共6页
Based on observation data from the mini-type automatic weather station,the evapotranspiration quantity of reference crops from artificial grassland in three river sources areas was estimated by the method of FAO Penma... Based on observation data from the mini-type automatic weather station,the evapotranspiration quantity of reference crops from artificial grassland in three river sources areas was estimated by the method of FAO Penman-Monteith.The actual evapotranspiration quantity of grassland was calculated according to the synthetic crop coefficients referenced by FAQ-56,and the change of the actual evapotranspiration quantity of artificial grassland in three river sources areas as well as the relationship between the evapotranspiration quantity and climatic factors were studied.The results suggested that the seasonal change of actual evapotranspiration quantity in grassland was expressed in a single peak curve with the peak in the middle August,and daily transpiration quantity in summer was significantly larger than that in winter.The evapotranspiration was significantly correlated with air temperature,solar radiation and relative humidity,but not significantly correlated with wind speed.Effects of climatic factors on the evapotranspiration quantity of artificial grassland were ordered as follow:air temperature(T)>solar radiation(Ra)>relative humidity(RH)>wind speed(u2). 展开更多
关键词 three RIVER SOURCES Artificial GRASSLAND EVAPOTRANSPIRATION CLIMATIC factor
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基于Three Factor+C模型改进的地形辐射校正方法 被引量:3
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作者 张伟阁 杨辽 +1 位作者 曹良中 贾洋 《国土资源遥感》 CSCD 北大核心 2015年第2期36-43,共8页
地形辐射校正(简称"地形校正")是复杂地形遥感定量化研究的关键环节之一。针对传统的经验地形校正模型存在的不同坡度采用同一校正系数的缺陷,基于简化的Three Factor+C模型,借鉴改进型Minnaert模型中坡度分级的思想,提出了基... 地形辐射校正(简称"地形校正")是复杂地形遥感定量化研究的关键环节之一。针对传统的经验地形校正模型存在的不同坡度采用同一校正系数的缺陷,基于简化的Three Factor+C模型,借鉴改进型Minnaert模型中坡度分级的思想,提出了基于Three Factor+C+坡度的地形校正方法。结果表明,使用Three Factor+C+坡度模型进行地形校正后的遥感图像,其均值、标准差、像元值与光照系数的相关性、阴阳坡光谱辐亮度值、离散指数和同质系数等6个指标均优于参与比较的C模型、SCS模型、Three Factor模型和Three Factor+C模型的对应指标。Three Factor+C+坡度模型有比较完善的物理机制,并较好地消除地形对光谱辐亮度的影响,值得推广。 展开更多
关键词 地形校正 three Factor+C模型 坡度分级 离散系数 同质系数
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Movement Properties of Pipe Flow Along Granite Slope of Three Gorges Area of Yangtze River in China 被引量:2
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作者 张洪江 史玉虎 +4 位作者 程云 盛前丽 肖辉杰 陈宗伟 常丹东 《Forestry Studies in China》 CAS 2002年第1期35-43,共9页
It is well known that, in most cases, soil water doesn't move in the form of laminar flow as described by Darcy law. Only when Reynolds number ( Re ) is no more than 10, does water movement follow Darcy law. A s... It is well known that, in most cases, soil water doesn't move in the form of laminar flow as described by Darcy law. Only when Reynolds number ( Re ) is no more than 10, does water movement follow Darcy law. A soil profile with 2 9 m long and 2 13 2 60 m deep was excavated on a lower slope located at Zigui County, Hubei Province, China. Field observation found that soil pipes were mainly distributed in the transient layer between horizon B with higher degree of granite weathering and horizon C with lower degree of granite weathering. At the foot of the slope, about 5 7 soil pipes per meter were observed along the vertical direction of the slope. The observed results, obtained by continuous observation of soil pipes and pipe flow processes at granite slope for many rainfall events, indicate that the relationship between velocity of pipe flow and hydraulic gradient along the pipe is parabolic rather than linear. Based on the investigated data of soil, landform, and land use etc., combined with observed data of pipe flow derived from many rainfall events, a pipe flow model was developed. For velocity V p, discharge Q p of pipe flow and radius r of soil pipe, great similarity was found between simulated and observed values. Particularly, the simulated length of soil pipes reflects the great difference among soil pipes as a result of its different position in the soil profile. The length values of 4 soil pipes were estimated to be 98 1%, 27 6%, 11 0% and 3 0% of the longest distance of the catchment, respectively. As a special case of water movement, soil pipe flow follows Darcy Weisbach law. Discharge of pipe flow is much greater than infiltration discharge in common. Only when the depth of groundwater is more than the diameter of soil pipe and water layer submerges soil pipes during rainfall, may pipe flow occur. Under these circumstances, discharge of pipe flow is directly proportional to the depth of groundwater. 展开更多
关键词 soil pipe pipe flow granite slope the three Gorges area the Yangtze River pipe flow model
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