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Three Kinds of Special Relativity via Inverse Wick Rotation 被引量:4
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作者 郭汉英 黄超光 +1 位作者 徐湛 周彬 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第10期2477-2480,共4页
Since the special relativity can be viewed as the physics in an inverse Wick rotation of four-dimensional (4D) Euclid space, which is at almost equal footing with the 4D Riemann/Lobachevski space, there should be im... Since the special relativity can be viewed as the physics in an inverse Wick rotation of four-dimensional (4D) Euclid space, which is at almost equal footing with the 4D Riemann/Lobachevski space, there should be important physics in the inverse Wick rotation of 4D Riemann/Lobachevski space. Thus, there are three kinds of special relativity in de Sitter(dS)/Minkowski/anti-de Sitter(AdS) space at almost equal footing, respectively. There is an instanton tunnelling scenario in the Riemann-de Sitter case that may explain why A be positive and link with the multiverse. 展开更多
关键词 INVARIANT sPECIAL relativity sITTER sPACETIME sUPERGRAVITY CONsTANT GRAVITY
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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General relativity Quantum Mechanics space Time Dark Matter A New Fundamental Constant “K”
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Einstein’s Concept of Clock Synchronization Conflicts with the Second Relativity Postulate
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作者 Steven D. Deines 《Journal of Modern Physics》 2024年第7期985-1000,共16页
Einstein defined clock synchronization whenever photon pulses with timetags traverse a fixed distance between two clocks with equal time spans ineither direction. Using the second relativity postulate, he found clocks... Einstein defined clock synchronization whenever photon pulses with timetags traverse a fixed distance between two clocks with equal time spans ineither direction. Using the second relativity postulate, he found clocksmounted on a rod uniformly moving parallel with the rod’s length cannot besynchronized, but clocks attached to a stationary rod can. He dismissed thisdiscrepancy by claiming simultaneity and clock synchronization were not commonbetween inertial frames, but this paper proves with both Galilean and Lorentztransformations that simultaneity and clock synchronization are preservedbetween inertial frames. His derivation means moving clocks can never besynchronized in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs daily contradict his results. No algebraic error occurred inEinstein’s derivations. The two cases of clocksattached to a rod reveal three major conflicts with the currentsecond postulate. The net velocity between a photon source and detector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity daily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest limit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished by expanding the second relativity postulate to incorporate thenet velocity between the photon source and detector with the emitted velocity c as components of the total velocity c. This means the magnitudeof the total photon velocity can exceed the speed limit (299792458 m/s) set by the standard velocity c. . 展开更多
关键词 special relativity sIMULTANEITY Clock synchronization Photon speed Lorentz Transformation Galilean Transformation
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Spherically Symmetric Problem of General Relativity for a Fluid Sphere
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作者 Valery V. Vasiliev Leonid V. Fedorov 《Journal of Modern Physics》 2024年第4期401-415,共15页
The paper is devoted to a spherically symmetric problem of General Relativity (GR) for a fluid sphere. The problem is solved within the framework of a special geometry of the Riemannian space induced by gravitation. A... The paper is devoted to a spherically symmetric problem of General Relativity (GR) for a fluid sphere. The problem is solved within the framework of a special geometry of the Riemannian space induced by gravitation. According to this geometry, the four-dimensional Riemannian space is assumed to be Euclidean with respect to the space coordinates and Riemannian with respect to the time coordinate. Such interpretation of the Riemannian space allows us to obtain complete set of GR equations for the external empty space and the internal spaces for incompressible and compressible perfect fluids. The obtained analytical solution for an incompressible fluid is compared with the Schwarzchild solution. For a sphere consisting of compressible fluid or gas, a numerical solution is presented and discussed. 展开更多
关键词 General relativity spherically symmetric Problem Fluid sphere
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Planck Quantised General Relativity Theory Written on Different Forms
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第6期2281-2301,共21页
This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in ot... This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in other papers. We also explore a relatively new general relativity-inspired field equation based on the original Newtonian mass, which is very different from today’s kilogram mass. Additionally, we examine two other field equations based on collision space-time, where both energy and matter can be described simply as space and time. We are thereby fulfilling Einstein’s dream of a theory where energy and mass are not needed, or are just aspects of space and time. If this is extended beyond the 4-dimensional space-time formalism of general relativity theory to a 6-dimensional framework with 3 space dimensions and 3 time dimensions, this ultimately reveals that they are two sides of the same coin. In reality, it is a three-dimensional space-time theory, where space and time are just two sides of the same coin. 展开更多
关键词 General relativity Planck Quantization Compton Frequency Composite Constant G Quantum Gravity Unification Collision space-Time
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Modified Lorentz Transformations and Space-Time Splitting According to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第7期2467-2489,共23页
Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fab... Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fabric of space-time into a positive subspace-time that represents the space of causality and a negative subspace-time which represents a space without causality, thus, in the special case, we have new transformations for the coordinates of space and time modified from Lorentz transformations specific to each subspace, where the contraction of length disappears and the speed of light is no longer a universal constant. In the general case, we have new types of matric tensor, one for positive subspace-time and the other for negative subspace-time. We also find that the speed of the photon decreases in positive subspace-time until it reaches zero and increases in negative subspace-time until it reaches the speed of light when the photon reaches the Schwarzschild radius. 展开更多
关键词 Four-Dimensional Vector Analysis Four-Dimensional subspace Causal space Analysis of the speed of Light Inverse Theory of relativity
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Between Quantum Mechanics and General Relativity
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作者 Walter James Christensen Jr. 《Journal of Modern Physics》 2024年第8期1199-1228,共30页
The origin of elementary particle mass is considered as a function of n-valued graviton quanta. To develop this concept we begin in a cold region of “empty space” comprised of only microscopic gravitons oscillating ... The origin of elementary particle mass is considered as a function of n-valued graviton quanta. To develop this concept we begin in a cold region of “empty space” comprised of only microscopic gravitons oscillating at angular frequency ω. From opposite directions enters a pair of stray protons. Upon colliding, heat and energy are released. Customarily, this phase and what follows afterward would be described by Quantum Chromodynamics (QCD). Instead, we argue for an intermediary step. One in which neighboring gravitons absorb discrete amounts of plane-wave energy. Captured by the graviton, the planewave becomes a standing wave, whereupon its electromagnetic energy densities are converted into gravitational quanta. Immediately thereafter an elementary particle is formed and emitted, having both mass and spin. From absorption to conversion to emission occurs in less than 3.7 × 10−16 s. During this basic unit of hybrid time, general relativity and quantum physics unite into a common set of physical laws. As additional stray protons collide the process continues. Over eons, vast regions of spacetime become populated with low-mass particles. These we recognize to be dark matter by its effects on large scale structures in the universe. Its counterpart, dark energy, arises when the conversion of gravitational quanta to particle emission is interrupted. This causes the gravitational quanta to be ejected. It is recognized by its large scale effects on the universe. 展开更多
关键词 Dark Matter and Energy Gravitational Quanta Graviton standing Wave schwarzschild Metric General relativity Quantum Physics Unified Field Theory Blackholes
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Relativistic Mechanics in Positive and Negative Subspace-Time according to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第11期3784-3815,共32页
In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of ... In the second paper on the inverse relativity model, we explained in the first paper [1] that analyzing the four-dimensional displacement vector on space-time according to a certain approach leads to the splitting of space-time into positive and negative subspace-time. Here, in the second paper, we continue to analyze each of the four-dimensional vectors of velocity, acceleration, momentum, and forces on the total space-time fabric. According to the approach followed in the first paper. As a result, in the special case, we obtain new transformations for each of the velocity, acceleration, momentum, energy, and forces specific to each subspace-time, which are subject to the positive and negative modified Lorentz transformations described in the first paper. According to these transformations, momentum remains a conserved quantity in the positive subspace and increases in the negative subspace, while the relativistic total energy decreases in the positive subspace and increases in the negative subspace. In the general case, we also have new types of energy-momentum tensor, one for positive subspace-time and the other for negative subspace-time, where the energy density decreases in positive subspace-time and increases in negative subspace-time, and we also obtain new gravitational field equations for each subspace-time. 展开更多
关键词 4D Velocity Vector Analysis Positive subspace Negative subspace Negative Relativistic Mechanics Positive Tensor of Energy and Momentum Inverse Theory of relativity
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Motion and Special Relativity in Complex Spaces
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 special relativity Complex space and Time Models and Dramatic sR simplification Complex Time and space separation Complex Time Interpretation
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The Origin of the Flat Rotation Curves in Spiral Galaxies: The Hidden Roles of Glitching SMDEOs and Emission of Gravitational Waves
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作者 Ahmad A. Hujeirat Peter Berczik 《Journal of Modern Physics》 2024年第10期1523-1542,共20页
Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. Th... Supermassive DEOs (SMDEOs) are cosmologically evolved objects made of irreducible incompressible supranuclear dense superfluids: The state we consider to govern the matter inside the cores of massive neutron stars. These cores are practically trapped in false vacua, rendering their detection by outside observers impossible. Based on massive parallel computations and theoretical investigations, we show that SMDEOs at the centres of spiral galaxies that are surrounded by massive rotating torii of normal matter may serve as powerful sources for gravitational waves carrying away roughly 1042 erg/s. Due to the extensive cooling by GWs, the SMDEO-Torus systems undergo glitching, through which both rotational and gravitational energies are abruptly ejected into the ambient media, during which the topologies of the embedding spacetimes change from curved into flatter ones, thereby triggering a burst gravitational energy of order 1059 erg. Also, the effects of glitches found to alter the force balance of objects in the Lagrangian-L1 region between the central SMDEO-Torus system and the bulge, enforcing the enclosed objects to develop violent motions, that may explain the origin of the rotational curve irregularities observed in the innermost part of spiral galaxies. Our study shows that the generated GWs at the centres of galaxies, which traverse billions of objects during their outward propagations throughout the entire galaxy, lose energy due to repeatedly squeezing and stretching the objects. Here, we find that these interactions may serve as damping processes that give rise to the formation of collective forces f∝m(r)/r, that point outward, endowing the objects with the observed flat rotation curves. Our approach predicts a correlation between the baryonic mass and the rotation velocities in galaxies, which is in line with the Tully-Fisher relation. The here-presented self-consistent approach explains nicely the observed rotation curves without invoking dark matter or modifying Newtonian gravitation in the low-field approximation. 展开更多
关键词 General relativity: Black Holes Neutron stars Quantum Fields: QCD Condensed Matter INCOMPREssIBILITY sUPERFLUIDITY Cosmology: Galaxy Formation spiral Galaxies Dark Matter rotation Curves
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Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 special relativitys Hyperbolic Versus Circular Versions Galilean Kinematics Partial Equivalence of sR and Newton’s Theories Algebra of Relativistic and the Corresponding Galilean Velocities
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Emission Theory with Re-Emission of Photons by the Medium—Instead of Special Relativity
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作者 Gtnnadiy Sokolov Vitali Sokolov 《Optics and Photonics Journal》 2024年第4期47-73,共27页
Instead of relying on the erroneous principles of Special Relativity, this paper proposes a new theory based on the emission of photons by a source and their re-emission by a transparent medium. Through over 60 articl... Instead of relying on the erroneous principles of Special Relativity, this paper proposes a new theory based on the emission of photons by a source and their re-emission by a transparent medium. Through over 60 articles, we have demonstrated that Special Relativity is based on optical experiments and observations that have been incorrectly explained by the theory of a non-existent ether. Our findings show that all known experiments can be explained using classical concepts of space and time, thereby refuting the theory of relativity. This article also addresses the fallacy of the widely accepted etheric Doppler effects and its significant role in the history of science. 展开更多
关键词 The Fallacy of the Theory of relativity The New Theory of Light The Fallacy of the Doppler Effect and Its Role in the Development of science Analysis of the Main Optical Experiments
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基于ROAV法与PCA-TOPSIS法冰葡萄酒香气质量综合评价
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作者 张杨 曲绎霖 +2 位作者 孙永德 孔维府 李红娟 《中国酿造》 北大核心 2025年第1期258-268,共11页
该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款... 该研究以四款代表性国产冰酒(编号为1号~4号)为研究对象,采用顶空-固相微萃取(HS-SPME)结合气质联用(GC-MS)技术测定冰酒的挥发性香气成分,并构建主成分分析(PCA)-优劣解距离法(TOPSIS)模型对冰酒香气品质进行分析评价。结果表明,四款冰酒共检测出118种挥发性香气成分,其中脂肪酸乙酯类18种、乙酸酯类8种、其他酯类24种、醇类13种、萜烯类12种、降异戊二烯衍生物4种、酸类5种、醛酮类9种、芳香族化合物15种、其他类10种;四款冰酒中香气成分的种类与含量差别显著。通过相对气味活度值(ROAV)筛选出22种重要香气物质(ROAV>0.1),10种关键香气物质(ROAV>1)。相关性结果表明,辛酸乙酯与苯乙醛呈显著负相关(P<0.05)、与大马士酮呈极显著负相关(P<0.01);大马士酮与苯乙醛呈显著正相关(P<0.05)、与癸酸乙酯和辛酸乙酯呈极显著负相关(P<0.01)。PCA-TOPSIS得出四款冰酒的香气评价结果Si(相对接近度)依次为0.804(4号)>0.572(2号)>0.411(1号)>0.229(3号),表明4号冰酒香气品质最优。 展开更多
关键词 冰葡萄酒 香气质量评价 相对气味活度值 主成分分析法 优劣解距离法
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基于动态相渗Arps产量模型的特高含水后期开发指标预测——以大庆长垣杏北开发A区为例
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作者 杨宁 姜贵璞 《大庆石油地质与开发》 北大核心 2025年第1期77-85,共9页
针对特高含水开发阶段传统油水相渗比与含水饱和度的半对数关系曲线不再是直线关系(出现下翘),传统油藏工程方法在特高含水及以后开发阶段适用性较差的问题,利用全过程动态相渗与传统油藏工程理论融合推导的方法,基于动态相渗的Arps产... 针对特高含水开发阶段传统油水相渗比与含水饱和度的半对数关系曲线不再是直线关系(出现下翘),传统油藏工程方法在特高含水及以后开发阶段适用性较差的问题,利用全过程动态相渗与传统油藏工程理论融合推导的方法,基于动态相渗的Arps产量模型对大庆长垣油田特高含水后期开发指标进行预测。结果表明:使用动态相渗Arps产量模型在特高含后水期及以后开发阶段预测指标时,误差相对较小,精度大幅提高,具有更强的适用性。研究成果为精准预测指标变化趋势、科学编制油田产量规划方案、及时调整开发对策提供了依据。 展开更多
关键词 特高含水后期 下翘 动态相渗 动态相渗Arps产量模型 误差
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血清PSA水平与MRI相关参数对老年前列腺良恶性病变的诊断价值
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作者 安宁 何宏艳 +3 位作者 程佳琪 程晓露 赵增喜 张瑞 《河北北方学院学报(自然科学版)》 2025年第2期31-34,38,共5页
目的探讨血清PSA水平与MRI相关参数对老年前列腺良恶性病变的诊断价值。方法选取90例老年前列腺癌患者为观察组,同期90例老年前列腺良性增生患者为对照组。均给予MR扩散加权成像检查,测量其相应的表观扩散系数(apparent diffusion coeff... 目的探讨血清PSA水平与MRI相关参数对老年前列腺良恶性病变的诊断价值。方法选取90例老年前列腺癌患者为观察组,同期90例老年前列腺良性增生患者为对照组。均给予MR扩散加权成像检查,测量其相应的表观扩散系数(apparent diffusion coefficient,ADC),计算ADCmean及相对平均ADC值(relative ADC_(mean),rADCmean)。应用酶联免疫吸附法检测血清PSA水平。收集患者人口学资料、体格检查资料、家族史、个人史及临床资料等,采用单因素及多因素Logistic回归模型分析影响前列腺病变良恶性诊断的独立影响因素;采用受试者工作特征曲线评估不同的预测模型对前列腺癌的诊断效能。结果2组患者血清PSA水平、ADCmean及rADCmean组间差异有统计学意义(P<0.05)。血清PSA水平、ADCmean及rADCmean是老年前列腺恶性肿瘤的独立影响因素;血清PSA的AUC为0.848(0.786~0.910),ADCmean的AUC为0.747(0.676~0.817),rADCmean的AUC为0.788(0.721~0.854),血清PSA联合ADCmean及rADCmean的AUC为0.929(0.893~0.966)。结论血清PSA联合MRI相关参数可显著提高对老年前列腺良恶性病变的诊断效能,对临床上早期区分前列腺良恶性肿瘤具有重要的参考价值。 展开更多
关键词 血清PsA 表观扩散系数 相对平均表观扩散系数 前列腺良恶性病变 老年
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Study on association rules mining based on semantic relativity 被引量:2
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作者 张磊 夏士雄 +1 位作者 周勇 夏战国 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期358-360,共3页
An association rules mining method based on semantic relativity is proposed to solve the problem that there are more candidate item sets and higher time complexity in traditional association rules mining.Semantic rela... An association rules mining method based on semantic relativity is proposed to solve the problem that there are more candidate item sets and higher time complexity in traditional association rules mining.Semantic relativity of ontology concepts is used to describe complicated relationships of domains in the method.Candidate item sets with less semantic relativity are filtered to reduce the number of candidate item sets in association rules mining.An ontology hierarchy relationship is regarded as a directed acyclic graph rather than a hierarchy tree in the semantic relativity computation.Not only direct hierarchy relationships,but also non-direct hierarchy relationships and other typical semantic relationships are taken into account.Experimental results show that the proposed method can reduce the number of candidate item sets effectively and improve the efficiency of association rules mining. 展开更多
关键词 ONTOLOGY association rules mining semantic relativity
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An Analysis of Students' Mistakes through Linguistic Relativity
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作者 赵瑶 《海外英语》 2013年第17期116-117,共2页
Sapir-Whorf Hypothesis is controversial, but the Linguistic Relativity is universally accepted by scholars. Through ana lyzing the causes of the mistakes that students often make during English learning and the relati... Sapir-Whorf Hypothesis is controversial, but the Linguistic Relativity is universally accepted by scholars. Through ana lyzing the causes of the mistakes that students often make during English learning and the relationship among thoughts, cultures and languages, this paper argues that language can influence people's thoughts and people's thoughts can influence the acquisi tion of a second language. 展开更多
关键词 LINGUIsTIC relativity THOUGHTs CULTUREs LANGUAGEs
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农村医疗保险的减贫效应研究——基于CFPS 2018的实证分析 被引量:2
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作者 罗文剑 罗梁秀 《北京航空航天大学学报(社会科学版)》 CSSCI 2024年第1期101-107,共7页
基于中国家庭追踪调查2018年(CFPS 2018)的数据,以相对贫困线作为贫困标准,采用二元Logistic模型实证评估农村医疗保险制度的减贫效应及其异质性。整体样本回归结果表明,农村医疗保险减贫效应显著,在相对贫困线标准下降低了43.0%的贫困... 基于中国家庭追踪调查2018年(CFPS 2018)的数据,以相对贫困线作为贫困标准,采用二元Logistic模型实证评估农村医疗保险制度的减贫效应及其异质性。整体样本回归结果表明,农村医疗保险减贫效应显著,在相对贫困线标准下降低了43.0%的贫困发生率。异质性分析结果表明,农村医疗保险减贫效应在年龄、性别方面存在差异:在年龄方面,农村医疗保险对于中老年人的减贫效应更为显著;在性别方面,农村医疗保险对于女性的减贫效应总体高于男性。为了充分发挥农村居民医疗保险减贫的制度效能,建议:优化医疗保险内部制度设计,强化经济绩效;下沉优质医疗卫生资源,提高健康绩效;建立长效机制,提高医疗保险减贫效应精准性。 展开更多
关键词 农村居民 医疗保险 减贫 相对贫困 绩效
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基于CLDAS土壤相对湿度的云南农业干旱监测
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作者 金燕 徐凌 +2 位作者 周群 鲁韦坤 孙帅 《中国农业气象》 CSCD 2024年第1期79-90,共12页
选取2016-2020年云南37个土壤水分观测站逐日0-10cm土层相对湿度观测数据和逐日降水、气温观测资料,采用线性插值法,将CLDAS格点数据插值到观测站点上,用于与站点观测数据对比分析。利用回归订正法对插值后的CLDAS土壤相对湿度产品进行... 选取2016-2020年云南37个土壤水分观测站逐日0-10cm土层相对湿度观测数据和逐日降水、气温观测资料,采用线性插值法,将CLDAS格点数据插值到观测站点上,用于与站点观测数据对比分析。利用回归订正法对插值后的CLDAS土壤相对湿度产品进行订正。采用相对误差、平均偏差、相关系数、标准差和均方根误差统计指标,定量评估CLDAS土壤相对湿度在云南的适用性。结果表明:云南土壤水分观测站相对湿度数据观测有效率不高,选用陆面融合数据开展农业干旱监测十分必要;云南地区近80%的CLDAS土壤相对湿度与土壤水分观测站观测值的相对误差绝对值<30%,数据可信度高;在干旱发生频率高的云南中部地区,CLDAS土壤相对湿度与土壤水分观测站观测值的相关系数均在0.8以上,平均偏差小于10%。从农业干旱监测效果来看,基于CLDAS土壤相对湿度的干旱监测指标能很好地描述由气温和降水异常导致的土壤墒情变化,当日降水量接近或超过5.0mm时,能快速响应轻旱站点数的减少;当连续有效降水发生后,监测指标可反映中等及以上等级农业干旱的缓解。综合来看,CLDAS土壤相对湿度在云南农业干旱监测的适用性好。 展开更多
关键词 CLDAs 土壤相对湿度 云南 农业干旱
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基于HSV空间的煤矿井下低光照图像增强方法 被引量:2
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作者 张亚邦 李佳悦 王满利 《红外技术》 CSCD 北大核心 2024年第1期74-83,共10页
针对煤矿井下采集到的图像对比度低、光照不均和细节信息弱等问题,提出一种基于色相-饱和度-明度(Hue-Saturation-Value,HSV)颜色空间的煤矿井下低光照图像增强方法。该方法基于图像的HSV空间,通过对低光照图像的亮度通道V通道的主要结... 针对煤矿井下采集到的图像对比度低、光照不均和细节信息弱等问题,提出一种基于色相-饱和度-明度(Hue-Saturation-Value,HSV)颜色空间的煤矿井下低光照图像增强方法。该方法基于图像的HSV空间,通过对低光照图像的亮度通道V通道的主要结构和边缘细节分别进行对比度增强,这样可以更好地抑制图像细节丢失,同时可以较好地再现原图中的轮廓和纹理细节。首先,将输入的煤矿井下低光照图像转换到HSV空间,利用相对全变分滤波(RTV)与改进的边窗滤波(SWF),分别对提取的V通道图像进行主要结构提取和轮廓边缘保留,对其非线性灰度拉伸后利用主成分分析融合技术(PCA)重构V通道图像,即融合V通道图像的主要结构和精细结构,最后合成图像,完成图像增强。通过实验验证,提出的基于HSV空间的煤矿井下低光照图像增强方法,在色彩和边缘模糊处理等方面表现良好,在煤矿井下工作面等环境中,对图像进行定量和定性实验,结果表明,与6种方法相比,增强图像的对比度、自然度和图像细节方面表现更好。 展开更多
关键词 图像增强 HsV空间 煤矿井 低光照图像 相对全变分滤波 边窗滤波
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