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Doppler Effect: A Look from Biology Aging
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作者 Jorge Barragán Sebastián Sánchez 《Advances in Aging Research》 CAS 2024年第4期75-84,共10页
The Doppler effect can be defined as the frequency shift suffered by a wave phenomenon, when there is a difference in relative speed between the waves generated and their source. We know that it occurs in the case of ... The Doppler effect can be defined as the frequency shift suffered by a wave phenomenon, when there is a difference in relative speed between the waves generated and their source. We know that it occurs in the case of mechanical and electromagnetic waves. We propose to generalize the Doppler effect to the case of frequency changes of certain oscillatory variables in biology before and after puberty, starting from the basis that a metabolically accelerated system is equivalent to a mechanically accelerated system. We then established the following objectives: To verify if there is an average difference in heart and respiratory rates, before and after puberty. To verify the association of these frequency differences with the metabolic activity estimated as basal metabolic rate or BMR. We studied heart and respiratory rate data from healthy people of both sexes, verifying the frequency distribution before and after puberty. We also study the relationship of the frequency distribution with the evolution of the basal metabolic rate throughout life. Analysis of the results shows that the highest heart and respiratory rates occur before puberty, while the lowest rates occur after puberty. A high correlation of the evolution of the variables studied with the evolution of the metabolic acceleration of the system throughout life is also evident. Taking into account that a mechanically accelerated system is equivalent to a metabolically accelerated system, we can conclude that the frequency distribution found is the expression of a generalization of the Doppler effect in the case of biological physical systems. 展开更多
关键词 Oscillatory Variables Metabolic Acceleration Mechanical Acceleration Equivalence principle Non-Inertial System Rate of Change
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Gravity and the Nature of Physical Interactions
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作者 Kajetan Młynarski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1578-1612,共35页
This work is a kind of thought experiment aimed at answering the question: what might a theory look like in which time and space (spacetime) are not fundamental? The article formulates theoretical frameworks that intr... This work is a kind of thought experiment aimed at answering the question: what might a theory look like in which time and space (spacetime) are not fundamental? The article formulates theoretical frameworks that introduce the number of spacetime dimensions, the principle of equivalence of mass, and the value of the gravitational constant not as empirically given data, but as results of theoretical deduction. This analysis opens up potential connections between gravitational and electrostatic interactions, proposing a new approach to traditional physical assumptions. The theory is presented in a preliminary form, intended to inspire possible further research. The final part of the paper proposes experiments to verify these ideas. 展开更多
关键词 Time SPACE GRAVITY principle of Equivalence Gravitational Constant Planck Mass
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Spin-Spin Interactions in Gauge Theory of Gravity, Violation of Weak Equivalence Principle and New Classical Test of General Relativity 被引量:1
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作者 WU Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1533-1540,共8页
For a long time, it has been generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. B... For a long time, it has been generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. But this is not true. By studying the motion of a spinning particle in gravitational field, it is found that there exist spin-spin interactions in gauge theory of gravity. Its mechanism is that a spinning particle will generate gravitomagnetic field in space-time, and this gravitomagnetic field will interact with the spin of another particle, which will cause spin-spin interactions. So, spin-spin interactions are transmitted by gravitational field. The form of spin-spin interactions in post Newtonian approximations is deduced. This result can also be deduced from the Papapetrou equation. This kind of interaction will not affect the renormalizability of the theory. The spin-spin interactions will violate the weak equivalence principle, and the violation effects are detectable. An experiment is proposed to detect the effects of the violation of the weak equivalence principle. 展开更多
关键词 spin-spin interactions weak equivalence principle equation of motion of a spinning particle experimental test of gravity theory post-Newtonian approximation
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Correlation method estimation of the modulation signal in the weak equivalence principle test 被引量:1
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作者 Jie Luo Liang-Cheng Shen +2 位作者 Cheng-Gang Shao Qi Liu Hui-Jie Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期136-142,共7页
In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the fre... In a test of the weak equivalence principle (WEP) with a rotating torsion pendulum, it is important to estimate the amplitude of the modulation signal with high precision. We use a torsional filter to remove the free oscillation signal and employ the correlation method to estimate the amplitude of the modulation signal. The data analysis of an experiment shows that the uncertainties of amplitude components of the modulation signal obtained by the correlation method are in agreement with those due to white noise. The power spectral density of the modulation signal obtained by the correlation method is about one order higher than the thermal noise limit. It indicates that the correlation method is an effective way to estimate the amplitude of the modulation signal and it is instructive to conduct a high-accuracy WEP test. 展开更多
关键词 weak equivalence principle test correlation method amplitude estimation thermal noise limit
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Systematic error suppression scheme of the weak equivalence principle test by dual atom interferometers in space based on spectral correlation 被引量:1
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作者 Jian-Gong Hu Xi Chen +2 位作者 Li-Yong Wang Qing-Hong Liao Qing-Nian Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第11期197-202,共6页
Systematic error suppression and test data processing are very important in improving the accuracy and sensitivity of the atom interferometer(AI)-based weak-equivalence-principle(WEP) test in space. Here we present a ... Systematic error suppression and test data processing are very important in improving the accuracy and sensitivity of the atom interferometer(AI)-based weak-equivalence-principle(WEP) test in space. Here we present a spectrum correlation method to investigate the test data of the AI-based WEP test in space by analyzing the characteristics of systematic errors and noises. The power spectrum of the Eotvos coefficient η, systematic errors, and noises in AI-based WEP test in space are analyzed and calculated in detail. By using the method, the WEP violation signal is modulated from direct current(DC) frequency band to alternating current(AC) frequency band. We find that the signal can be effectively extracted and the influence of systematic errors can be greatly suppressed by analyzing the power spectrum of the test data when the spacecraft is in an inertial pointing mode. Furthermore, the relation between the Eotvos coefficient η and the number of measurements is obtained under certain simulated parameters. This method will be useful for both isotopic and nonisotopic AI-based WEP tests in space. 展开更多
关键词 atom interferometer weak equivalence principle spectral correlation systematic error
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Effect of gravity gradient in weak equivalence principle test
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作者 徐家豪 邵成刚 +3 位作者 罗杰 刘祺 邾琳 赵慧慧 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期61-65,共5页
A high accuracy test of the weak equivalence principle(WEP) is of great scientific significance no matter whether its result is positive. We analyze the gravity gradient effect which is a main systematic error sourc... A high accuracy test of the weak equivalence principle(WEP) is of great scientific significance no matter whether its result is positive. We analyze the gravity gradient effect which is a main systematic error source in the test of WEP.The result shows that the uncompensated gravity gradient effect from the coupling term of the dominated gravity gradient multipole moment component q_(21) and the relative multipole field component Q_(21) contributes to an uncertainty of 1×10^(-11) on the E otv os parameter. We make a Q_(21) compensation to reduce the effect by about 20 times, and the limit of the test precision due to this coupling is improved to a level of a part in 10^(13). 展开更多
关键词 weak equivalence principle test gravity gradient effect test precision gravity gradient compensation
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Suppression of Coriolis error in weak equivalence principle test using ^85Rb-^87Rb dual-species atom interferometer
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作者 Wei-Tao Duan Chuan He +5 位作者 Si-Tong Yan Yu-Hang Ji Lin Zhou Xi Chen Jin Wang Ming-Sheng Zhan 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第7期77-84,共8页
Coriolis effect is an important error source in the weak equivalence principle(WEP)test using atom interferometer.In this paper,the problem of Coriolis error in WEP test is studied theoretically and experimentally.In ... Coriolis effect is an important error source in the weak equivalence principle(WEP)test using atom interferometer.In this paper,the problem of Coriolis error in WEP test is studied theoretically and experimentally.In theoretical simulation,the Coriolis effect is analyzed by establishing an error model.The measurement errors of Eotvos coefficient(η)in WEP test related to experimental parameters,such as horizontal-velocity difference and horizontal-position difference of atomic clouds,horizontal-position difference of detectors,and rotation compensation of Raman laser’s mirror are calculated.In experimental investigation,the position difference between^85Rb and^87Rb atomic clouds is reduced to 0.1 mm by optimizing the experimental parameters,an alternating detection method is used to suppress the error caused by detection position difference,thus the Coriolis error related to the atomic clouds and detectors is reduced to 1.1 × 10^-9.This Coriolis error is further corrected by com pensating the rotation of Raman laser's mirror,and the total uncertainty o f rj measurement related to the Coriolis effect is reduced as δη=4.4 × 10^-11. 展开更多
关键词 atom interferometer weak equivalence principle test Coriolis effect
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Design and Evaluation of a Differential Accelerometer for Drop-Tower Equivalence Principle Test with Rotating Masses
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作者 Feng-Tian Han Tian-Yi Liu +1 位作者 Xiao-Xia He Qiu-Ping Wu 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期13-17,共5页
A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measureme... A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measurement is performed by placing the two concentric masses of very different momenta in a vacuum drop capsule which is falling freely in the Earth's gravitational field. A nonzero output of the differential aeeelerometer is an indication of possible violation of new equivalence principle (NEP). We present the conceptual design of a modified free-fall NEP experiment which can be performed at the Belting drop tower. Design and evaluation of the differential accelerometer with a hybrid electrostatic/magnetic suspension system are presented to accommodate for operation on ground and drop-tower tests. Details specific to the measurement uncertainty are discussed to yield an NEP test accuracy of 7.2×10^-9. 展开更多
关键词 TM Design and Evaluation of a Differential Accelerometer for Drop-Tower Equivalence principle Test with Rotating Masses NEP
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Nutational Oscillatory Effect of the Test Body in Space Equivalence Principle Experiments
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作者 SHAOCheng-Gang ZHANGYuan-Zhong LUOjun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期211-214,共4页
The significance of quadrupole gravitational force is discussed for test mass in equivalence principle (EP), and the angular moment acting on a cylindrically symmetrical body due to quadrupole force is calculated, whi... The significance of quadrupole gravitational force is discussed for test mass in equivalence principle (EP), and the angular moment acting on a cylindrically symmetrical body due to quadrupole force is calculated, which will result in nutational oscillatory effect. The oscillations contain a perturbation with the same frequency of EP violation signal, which is mitigated by two different methods as in Galileo Galilei (GG) mission and μSCOPE. In GG the sensor for readout is sensitive to differential forces in the orbital plane perpendicular to spin axis of test cylinders. In order to mitigate the nutational oscillatory effect, test mass should be rapidly rotated with the spin axis. However, in μSCOPE, the readout sensitive axis is the symmetry axis in the orbital plane. This nutational oscillation will produce a second order effect in the rotation amplitude at twice the signal frequency, and could be subtracted easily, too. 展开更多
关键词 equivalence principle
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Determination of the thermal noise limit in test of weak equivalence principle with a rotating torsion pendulum
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作者 占文泽 罗杰 +3 位作者 邵成刚 郑第 殷蔚明 王典洪 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期56-61,共6页
Thermal noise is one of the most fundamental limits to the sensitivity in weak equivalence principle test with a rotating torsion pendulum. Velocity damping and internal damping are two of many contributions at the th... Thermal noise is one of the most fundamental limits to the sensitivity in weak equivalence principle test with a rotating torsion pendulum. Velocity damping and internal damping are two of many contributions at the thermal noise, and which one mainly limits the torsion pendulum in low frequency is difficult to be verified by experiment. Based on the conventional method of fast Fourier transform, we propose a developed method to determine the thermal noise limit and then obtain the precise power spectrum density of the pendulum motion signal. The experiment result verifies that the thermal noise is mainly contributed by the internal damping in the fiber in the low frequency torsion pendulum experiment with a high vacuum. Quantitative data analysis shows that the basic noise level in the experiment is about one to two times of the theoretical value of internal damping thermal noise. 展开更多
关键词 weak equivalence principle torsion pendulum thermal noise limit internal damping
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Deflection and stress of hollow CRCP slab under concentrated vehicle load 被引量:2
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作者 陈小兵 黄晓明 +1 位作者 丁建明 童金虎 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期213-216,共4页
Based on the equivalence principle of deflection and stress, the concentrated vehicle load which acts on the center of continuously reinforced concrete pavement (CRCP) is translated into the equivalent half-wave sin... Based on the equivalence principle of deflection and stress, the concentrated vehicle load which acts on the center of continuously reinforced concrete pavement (CRCP) is translated into the equivalent half-wave sine load by the Fourier transform. On the basis of this transform and the small deflection theory of elastic thin plates, the deflection and stress formulae of CRCP under the concentrated vehicle load with a hollow foundation are put forward. The sensitivity of parameters is analyzed. The results show that maximum deflection is directly proportional to the concentrated vehicle load and the slab width, and inversely proportional to the lateral bending stiffness and slab thickness. The effects of slab width and thickness are significant with regard to maximum deflection. Maximum stress is directly proportional to the concentrated vehicle load and the slab width as well as inversely proportional to slab thickness. The effect of slab thickness is significant with regard to maximum stress. According to the calculation results, the most effective measure to reduce maximum deflection and stress is to increase slab thickness. 展开更多
关键词 concentrated vehicle load equivalence principle half-wave sine load elastic thin plates hollow continuouslyreinforced concrete pavement slab deflection and stressformulae slab thickness
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Effect of aperture field distribution on the maximum radiated power at atmospheric pressure
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作者 赵朋程 郭立新 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期324-328,共5页
The air breakdown in the high-power antenna near-field region limits the enhancement of the radiated power. A model coupling the field equivalent principle and the electron number density equation is presented to stud... The air breakdown in the high-power antenna near-field region limits the enhancement of the radiated power. A model coupling the field equivalent principle and the electron number density equation is presented to study the breakdown process in the near-field region of the circular aperture antenna at atmospheric pressure. Simulation results show that, although the electric field in the near-field region is nonuniform, the electron diffusion has small influence on the breakdown process when the initial electron number density is uniform in space. The field magnitude distribution on the aperture plays an important role in the maximum radiated power above which the air breakdown occurs. The maximum radiated power also depends on the phase difference of the fields at the center and edge of the aperture, especially for the uniform field magnitude distribution. 展开更多
关键词 field equivalent principle aperture antenna air breakdown maximum radiated power
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TIME-TEMPERATURE-STRESS EQUIVALENCE AND ITS APPLICATION TO NONLINEAR VISCOELASTIC MATERIALS 被引量:7
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作者 Luo Wenbo Yang Ting-Qing An Qunli 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第3期195-199,共5页
Stress-dependence of the intrinsic time of viscoelastic materialsis investigated. The influence of stress level on the intrinsic timeis considered to be similar to that of temperature, pressure, solventcon- centration... Stress-dependence of the intrinsic time of viscoelastic materialsis investigated. The influence of stress level on the intrinsic timeis considered to be similar to that of temperature, pressure, solventcon- centration, damage and physical aging. Thetime-temperature-stress equivalence principle is proposed, byemploying which, the creep curves at different temperatures andstress level can be shifted into a master curve at referencetemperature and stress level. 展开更多
关键词 CREEP VISCOELASTICITY time-temperature-stress equivalence principle
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Remarks on interpretations of the Eotvos experiment and misinterpretation of E=mc^2 被引量:1
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作者 鲁重贤 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期635-639,共5页
The Eotvos experiment on the verification of equivalence between inertial mass and gravitational mass of a body is famous for its accuracy. A question is, however, can these experimental results be applied to the case... The Eotvos experiment on the verification of equivalence between inertial mass and gravitational mass of a body is famous for its accuracy. A question is, however, can these experimental results be applied to the case of a physical space in general relativity, where the space coordinates could be arbitrary? It is pointed out that it can be validly applied because it has been proven that Einstein's equivalence principle for a physical space must have a frame of reference with the Euclidean-like structure. Will claimed further that such an overall accuracy can be translated into an accuracy of the equivalence between inertial mass and each type of energy. It is shown that, according to general relativity, such a claim is incorrect. The root of this problem is due to an inadequate understanding of special relativity that produced the famous equation E=mc^2, which must be understood in terms of energy conservation. Concurrently, it is pointed out that this error is a problem in Will's book, ‘Theory and Experiment in Gravitational Physics'. 展开更多
关键词 Einstein's equivalence principle Einstein-Minkowski condition Euclidean-like structure Eotvos experiment weak equivalence principle E=MC^2
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The Problems in Trademark Translation and Their Solutions 被引量:1
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作者 HE Hui 《Sino-US English Teaching》 2007年第4期71-76,共6页
The good translation of trademarks should be accepted by most customers, which is the purpose of the trademarks translation. It arouses people's attention to the problems existing in trademark translation. This paper... The good translation of trademarks should be accepted by most customers, which is the purpose of the trademarks translation. It arouses people's attention to the problems existing in trademark translation. This paper probes two main problematic aspects in trademark translation: the problems in the aspect of the culture and the problems in the aspect of the language. Based on the main translating rule of "equivalence principle", it attempts to focus on the solutions to tackle the problems. 展开更多
关键词 TRADEMARK trademark translation equivalence principle functional equivalence
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Distributed Energy Saving Mechanism Based on CoMP in LTE-A System 被引量:1
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作者 Fei Zheng Wenjing Li +2 位作者 Luoming Meng Peng Yu Lei Peng 《China Communications》 SCIE CSCD 2016年第7期39-47,共9页
To reduce the energy consumption of the LTE-A system,a distributed energy-saving mechanism based on Co MP(Co MPDESM) is proposed to solve the inadequate coverage problem under the dormant cells.First,the network is di... To reduce the energy consumption of the LTE-A system,a distributed energy-saving mechanism based on Co MP(Co MPDESM) is proposed to solve the inadequate coverage problem under the dormant cells.First,the network is divided into clusters based on the equivalent cell principle.Then,we transfer global optimization into a group of subproblems.Second,a joint processing-based cooperative cell selection model is constructed to determine cooperative cells and dormant cells.Third,the compensative cells with a determined threshold are selected to control users' access.Finally,a simulation is implemented in Matlab.Results show that the energy-saving rate can reach 36.4% and that the mechanism meets the network coverage requirement.Thus,joint processing can be effectively applied in an energy saving mechanism and used to improve the network performance of edge users without increasing transmission power. 展开更多
关键词 LTE-A distributed energy-saving mechanism CoMP equivalent cell principle energy-saving rate
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Encoding Energy-Density as Geometry 被引量:3
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作者 Edwin Eugene Klingman 《Journal of Modern Physics》 2021年第9期1190-1209,共20页
Physicists possess an intuitive awareness of Euclidian space and time and Galilean transformation, and are then challenged with Minkowski space-time and Einstein’s curved space-time. Relativistic experiments support ... Physicists possess an intuitive awareness of Euclidian space and time and Galilean transformation, and are then challenged with Minkowski space-time and Einstein’s curved space-time. Relativistic experiments support the “time-dilation” interpretation and others support “curved space-time” interpretation. In this, and related work, we investigate the key issues in terms of the intuitive space-time frame. In particular, we provide alternative approaches to explain “time dilation” and to explain the energy density for gravity systems. We approach the latter problem from an information perspective. 展开更多
关键词 Curved Space-Time Gravitational Energy Stress-Energy Tensor Encoding Information in Geometry Time Dilation Equivalence principle Minkowski Relation Schwarzschild Metric Linearized General Relativity COSMOLOGY
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A New Fracability Evaluation Approach for Shale Reservoirs Based on Multivariate Analysis: A Case Study in Zhaotong Shale Gas Demonstration Zone in Sichuan, China
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作者 LIU Shanyong LI Lin +2 位作者 YUAN Yuan LOU Yishan LI Zhonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期1005-1014,共10页
Fracability characterizes the effectiveness of hydraulic fracturing.The existing assessment methods cannot reflect the actual value of the effectiveness due to a lack of comprehensive consideration and neglect of the ... Fracability characterizes the effectiveness of hydraulic fracturing.The existing assessment methods cannot reflect the actual value of the effectiveness due to a lack of comprehensive consideration and neglect of the influences of engineering factors.This study aims to solve this problem by implementing geological static data and production dynamic data in multivariate analysis in Zhaotong shale gas demonstration zone.First,the reservoir quality index(RQI)was introduced to evaluate the exploration potential by integrating the geological parameters with gray relational analysis.Moreover,the differences in fracturing fluid types and proppant sizes were considered,and the operating parameters were normalized on the basis of the equivalence principle.Finally,the general reservoir fracability index(GRFI)was proposed based on a dimensioned processing of the various parameters.A case study was conducted to verify the accuracy and feasibility of this new approach.The results demonstrate that(1)the organic carbon and gas content are adjusted to contribute the most to the calculation of the RQI,while the effective porosity contributes the least;(2)the fracturing scale is the main operating parameter determining the fracability,which has the strongest correlation with the effectiveness of fracking;and(3)the GRFI has a positive correlation with shale gas production,and the lower limit of the GRFI of 2,000 corresponds to a daily production of 50,000 m3/d;this value is defined as the threshold value of a stripper well.The GRFI is consistent with the productivity trend of shale gas wells in the research block,which suggests that the new model is accurate and practical for well candidate selection. 展开更多
关键词 fracability multivariate analysis equivalence principle network fracturing shale gas
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Common-mode noise rejection using fringe-locking method in WEP test by simultaneous dual-species atom interferometers
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作者 邓小兵 段小春 +3 位作者 毛德凯 周敏康 邵成刚 胡忠坤 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期174-178,共5页
We theoretically investigate the application of the fringe-locking method(FLM) in the dual-species quantum test of the weak equivalence principle(WEP).With the FLM,the measurement is performed invariably at the mi... We theoretically investigate the application of the fringe-locking method(FLM) in the dual-species quantum test of the weak equivalence principle(WEP).With the FLM,the measurement is performed invariably at the midfringe,and the extraction of the phase shift for atom interferometers is linearized.For the simultaneous interferometers,this linearization enables a good common-mode rejection of vibration noise,which is usually the main limit for high precision WEP tests of the dual-species kind.We note that this method also allows for an unbiased determination of the gravity accelerations difference,which meanwhile is ready to be implemented. 展开更多
关键词 weak equivalence principle dual-species atom interferometers fringe locking vibration noise rejection
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A SPACE THEORY BASIS FOR CURVE FITTING PROBLEMS
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作者 韩维信 《Transactions of Tianjin University》 EI CAS 1995年第2期194+192-194,共4页
itherto, a precision Concept for curve fitting problems has not been set. By using the theory of functional analysis, the author of this paper established a space theory basis for curve fitting problems. Also given in... itherto, a precision Concept for curve fitting problems has not been set. By using the theory of functional analysis, the author of this paper established a space theory basis for curve fitting problems. Also given in the paper is the precision concept of the curve fitting problems and the method for constructing the fitting of a curve satisfying given precision requirements. 展开更多
关键词 fitted space fitted curve uniform convergence least square approximation norm equivalence principle
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