Using a Linde reference, as well as another one from Padmanabhan for calculation of how the early universe expands, we obtain, by default the coefficient of scale factor expansion, t to the alpha value, with alpha bei...Using a Linde reference, as well as another one from Padmanabhan for calculation of how the early universe expands, we obtain, by default the coefficient of scale factor expansion, t to the alpha value, with alpha being approximately the square root of five in value. We from there make an estimate as to the number of initial particles produced in the very beginning, which leads us to conclude that a graviton, would be a preferred initial by product. The argument as to gravitons, also reflects a choice of how the decay of initial BEC condensates of Planck sized black holes would commence, using the work produced by Chavanis, as to BEC condensates and black holes. The object will be to obtain initial frequency spread plus strength of GW production plus a suggestion as to what polarization state may be accessible from initial conditions.展开更多
This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is no...This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is not possible to read a local linear scale factor in the direction of a coordinate axis immediately from the definition of a local linear scale factor,this paper considers the derivation of new formulae that enable local linear scale factors in the direction of coordinate x and y axes to be calculated.The formula for computing the local linear scale factor in any direction defined by dx and dy is also derived.Furthermore,the position and magnitude of the extreme values of the local linear scale factor are considered and new formulas derived.展开更多
Geometric or sub-scale modeling techniques are used for the evaluation of large and complex dynamic structures to ensure accurate reproduction of load path and thus leading to true dynamic characteristics of such stru...Geometric or sub-scale modeling techniques are used for the evaluation of large and complex dynamic structures to ensure accurate reproduction of load path and thus leading to true dynamic characteristics of such structures. The sub-scale modeling technique is very effective in the prediction of vibration characteristics of original large structure when the experimental testing is not feasible due to the absence of a large testing facility. Previous researches were more focused on free and harmonic vibration case with little or no consideration for readily encountered random vibration. A sub-scale modeling technique is proposed for estimating the vibration characteristics of any large scale structure such as Launch vehicles, Mega structures, etc., under various vibration load cases by utilizing precise scaled-down model of that dynamic structure. In order to establish an analytical correlation between the original structure and its scaled models, different scale models of isotropic cantilever beam are selected and analyzed under various vibration conditions( i.e. free, harmonic and random) using finite element package ANSYS. The developed correlations are also validated through experimental testing The prediction made from the vibratory response of the scaled-down beam through the established sets of correlation are found similar to the response measured from the testing of original beam structure. The established correlations are equally applicable in the prediction of dynamic characteristics of any complex structure through its scaled-down models. This paper presents modified sub-scale modeling technique that enables accurate prediction of vibration characteristics of large and complex structure under not only sinusoidal but also for random vibrations.展开更多
One of the crucial and challenging issues for researchers is presenting an appropriate approach to evaluate the aerodynamic characteristics of air cushion vehicles(ACVs)in terms of system design parameters.One of thes...One of the crucial and challenging issues for researchers is presenting an appropriate approach to evaluate the aerodynamic characteristics of air cushion vehicles(ACVs)in terms of system design parameters.One of these issues includes introducing a suitable approach to analyze the effect of geometric shapes on the aerodynamic characteristics of ACVs.The main novelty of this paper lies in presenting an innovative method to study the geometric shape effect on air cushion lift force,which has not been investigated thus far.Moreover,this paper introduces a new approximate mathematical formula for calculating the air cushion lift force in terms of parameters,including the air gap,lateral gaps,air inlet velocity,and scaling factor for the first time.Thus,we calculate the aerodynamic lift force applied to nine different shapes of the air cushions used in the ACVs in the present paper through the ANSYS Fluent software.The geometrical shapes studied in this paper are rectangular,square,equilateral triangle,circular,elliptic shapes,and four other combined shapes,including circle-rectangle,circle-square,hexagonal,and fillet square.Results showed that the cushion with a circular pattern produces the highest lift force among other geometric shapes with the same conditions.The increase in the cushion lift force can be attributed to the fillet with a square shape and its increasing radius compared with the square shape.展开更多
In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOG...In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOGs), three types of polarization-maintaining (PM) fibers are tested by using a 60Co γ-radiation source. The observed different mean wave- length shift (MWS) behaviors for different fibers are interpreted by color-center theory involving dose rate-dependent absorption bands in ultraviolet and visible ranges and total dose-dependent near-infrared absorption bands. To evaluate the mean wavelength variation in a fiber coil and the induced scale factor change for space-borne IFOGs under low radiation doses in a space environment, the influence of dose rate on the mean wavelength is investigated by testing four germanium (Ge) doped fibers and two germanium-phosphorus (Ge-P) codoped fibers irradiated at different dose rates. Experimental results indicate that the Ge-doped fibers show the least mean wavelength shift during irradiation and their mean wavelength of optical signal transmission in fibers will shift to a shorter wavelength in a low-dose-rate radiation environment. Finally, the change in the scale factor of IFOG resulting from the mean wavelength shift is estimated and tested, and it is found that the significant radiation-induced scale factor variation must be considered during the design of space-borne IFOGs.展开更多
Multifdelity surrogates(MFSs)replace computationally intensive models by synergistically combining information from diferent fdelity data with a signifcant improvement in modeling efciency.In this paper,a modifed MFS(...Multifdelity surrogates(MFSs)replace computationally intensive models by synergistically combining information from diferent fdelity data with a signifcant improvement in modeling efciency.In this paper,a modifed MFS(MMFS)model based on a radial basis function(RBF)is proposed,in which two fdelities of information can be analyzed by adaptively obtaining the scale factor.In the MMFS,an RBF was employed to establish the low-fdelity model.The correlation matrix of the high-fdelity samples and corresponding low-fdelity responses were integrated into an expansion matrix to determine the scaling function parameters.The shape parameters of the basis function were optimized by minimizing the leave-one-out cross-validation error of the high-fdelity sample points.The performance of the MMFS was compared with those of other MFS models(MFS-RBF and cooperative RBF)and single-fdelity RBF using four benchmark test functions,by which the impacts of diferent high-fdelity sample sizes on the prediction accuracy were also analyzed.The sensitivity of the MMFS model to the randomness of the design of experiments(DoE)was investigated by repeating sampling plans with 20 diferent DoEs.Stress analysis of the steel plate is presented to highlight the prediction ability of the proposed MMFS model.This research proposes a new multifdelity modeling method that can fully use two fdelity sample sets,rapidly calculate model parameters,and exhibit good prediction accuracy and robustness.展开更多
Estimation of random errors, which are due to shot noise of photomultiplier tube(PMT) or avalanche photodiode(APD) detectors, is very necessary in lidar observation. Due to the Poisson distribution of incident electro...Estimation of random errors, which are due to shot noise of photomultiplier tube(PMT) or avalanche photodiode(APD) detectors, is very necessary in lidar observation. Due to the Poisson distribution of incident electrons, there still exists a proportional relationship between standard deviation and square root of its mean value. Based on this relationship,noise scale factor(NSF) is introduced into the estimation, which only needs a single data sample. This method overcomes the distractions of atmospheric fluctuations during calculation of random errors. The results show that this method is feasible and reliable.展开更多
The scaled boundary finite element method (SBFEM) is a recently developed numerical method combining advantages of both finite element methods (FEM) and boundary element methods (BEM) and with its own special fe...The scaled boundary finite element method (SBFEM) is a recently developed numerical method combining advantages of both finite element methods (FEM) and boundary element methods (BEM) and with its own special features as well. One of the most prominent advantages is its capability of calculating stress intensity factors (SIFs) directly from the stress solutions whose singularities at crack tips are analytically represented. This advantage is taken in this study to model static and dynamic fracture problems. For static problems, a remeshing algorithm as simple as used in the BEM is developed while retaining the generality and flexibility of the FEM. Fully-automatic modelling of the mixed-mode crack propagation is then realised by combining the remeshing algorithm with a propagation criterion. For dynamic fracture problems, a newly developed series-increasing solution to the SBFEM governing equations in the frequency domain is applied to calculate dynamic SIFs. Three plane problems are modelled. The numerical results show that the SBFEM can accurately predict static and dynamic SIFs, cracking paths and load-displacement curves, using only a fraction of degrees of freedom generally needed by the traditional finite element methods.展开更多
We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmet...We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmetrical coupled networks are separately given based on the Lyapunov function method and the left eigenvalue theory. Numerical simulations for a generalized chaotic unified system are illustrated to verify the theoretical results.展开更多
To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where...To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes.展开更多
The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and pla...The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and plays a key role in bathymetry modeling over these regions.The Synthetic Aperture Radar(SAR)altimeters in the missions like CryoSat-2 and Sentinel-3A/3B can relieve waveform contamination that existed in conventional altimeters and provide data with improved accuracy and spatial resolution.In this study,we investigate the potential application of SAR altimetric gravity data in enhancing coastal bathymetry,where the effects on local bathymetry modeling introduced from SAR altimetry data are quantified and evaluated.Furthermore,we study the effects on bathymetry modeling by using different scale factor calculation approaches,where a partition-wise scheme is implemented.The numerical experiment over the South Sandwich Islands near Antarctica suggests that using SARbased altimetric gravity data improves local coastal bathymetry modeling,compared with the model calculated without SAR altimetry data by a magnitude of 3:55 m within 10 km of offshore areas.Moreover,by using the partition-wise scheme for scale factor calculation,the quality of the coastal bathymetry model is improved by 7.34 m compared with the result derived from the traditional method.These results indicate the superiority of using SAR altimetry data in coastal bathymetry inversion.展开更多
This study aimed to deal with three challenges:robustness,imperceptibility,and capacity in the image watermarking field.To reach a high capacity,a novel similarity-based edge detection algorithm was developed that fin...This study aimed to deal with three challenges:robustness,imperceptibility,and capacity in the image watermarking field.To reach a high capacity,a novel similarity-based edge detection algorithm was developed that finds more edge points than traditional techniques.The colored watermark image was created by inserting a randomly generated message on the edge points detected by this algorithm.To ensure robustness and imperceptibility,watermark and cover images were combined in the high-frequency subbands using Discrete Wavelet Transform and Singular Value Decomposition.In the watermarking stage,the watermark image was weighted by the adaptive scaling factor calculated by the standard deviation of the similarity image.According to the results,the proposed edge-based color image watermarking technique has achieved high payload capacity,imperceptibility,and robustness to all attacks.In addition,the highest performance values were obtained against rotation attack,to which sufficient robustness has not been reached in the related studies.展开更多
We revisit how we utilized how Weber in 1961 initiated the process of quantization of early universe fields to the issue of what was for a wormhole mouth. While the wormhole models are well understood, there is not su...We revisit how we utilized how Weber in 1961 initiated the process of quantization of early universe fields to the issue of what was for a wormhole mouth. While the wormhole models are well understood, there is not such a consensus as to how the mouth of a wormhole could generate signals. We try to develop a model for doing so and then revisit it, the Wormhole while considering a Tokamak model we used in a different publication as a way of generating GW, and Gravitons.展开更多
In this paper, three existing source spectral models for stochastic finite-fault modeling of ground motion were reviewed. These three models were used to calculate the far-field received energy at a site from a vertic...In this paper, three existing source spectral models for stochastic finite-fault modeling of ground motion were reviewed. These three models were used to calculate the far-field received energy at a site from a vertical fault and the mean spectral ratio over 15 stations of the Northridge earthquake, and then compared. From the comparison, a necessary measure was observed to maintain the far-field received energy independent of subfault size and avoid overestimation of the long- period spectra/level. Two improvements were made to one of the three models (i.e., the model based on dynamic comer frequency) as follows: (i) a new method to compute the subfault comer frequency was proposed, where the subfault comer frequency is determined based on a basic value calculated from the total seismic moment of the entire fault and an increment depending on the seismic moment assigned to the subfault; and (ii) the difference of the radiation energy from each suhfault was considered into the scaling factor. The improved model was also compared with the unimproved model through the far-field received energy and the mean spectral ratio. The comparison proves that the improved model allows the received energy to be more independent of subfault size than the unimproved model, and decreases the overestimation degree of the long-period spectral amplitude.展开更多
Based on symbolic computation system Maple and Lyapunov stability theory,an active control method isused to projectively synchronize two different chaotic systems—Lorenz-Chen-Lü system(LCL)and Rssler system,whic...Based on symbolic computation system Maple and Lyapunov stability theory,an active control method isused to projectively synchronize two different chaotic systems—Lorenz-Chen-Lü system(LCL)and Rssler system,which belong to different dynamic systems.In this paper,we achieve generalized projective synchronization between thetwo different chaotic systems by directing the scaling factor onto the desired value arbitrarily.To illustrate our result,numerical simulations are used to perform the process of the synchronization and successfully put the orbits of drivesystem(LCL)and orbits of the response system(Rssler system)in the same plot for understanding intuitively.展开更多
The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of ab...The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s;·V;with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s;·V;with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs.展开更多
We reduplicate the Book “Dark Energy” by M. Li, X.-D. Li, and Y. Wang, zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wavefunction just prior to the entrance of “gr...We reduplicate the Book “Dark Energy” by M. Li, X.-D. Li, and Y. Wang, zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wavefunction just prior to the entrance of “gravitons” to a small region of space-time prior to a nonsingular start to the universe. We compare this to a solution which worked out using Klauder Enhanced quantization, for the same given problem. The solution of the first Cosmological Constant problem relies upon the geometry of the multiverse generalization of CCC cosmology which is explained in this paper. The second solution used involves Klauder enhanced quantization. We look at energy given by our methods and compare and contrast it with the negative energy of the Rosen model for a mini sub-universe and estimate GW frequencies.展开更多
Our Methodology is to construct using a “trivial” solution to massive gravitons, and a nonsingular start for expansion of the universe. Our methodology has many unintended consequences, not the least is a relationsh...Our Methodology is to construct using a “trivial” solution to massive gravitons, and a nonsingular start for expansion of the universe. Our methodology has many unintended consequences, not the least is a relationship between a small time step, t, the minimum scale factor and even the tension or property values of the initial space-time wall, and that is a consequence of a “trivial” solution taking into account “massive” gravitons. <i>I.e.</i> this solution has a mass term times the partial derivative with respect to time of an expression in brackets. The expression in brackets is the cube of a scale factor minus the square of the scale factor. Bonus that this equation is set to zero. It is deemed trivial due to the insistence of having a singular solution. If that is dropped, we have a different venue. In addition, the Friedman equation for nonsingular cosmology can have a quadratic dependence upon a density (of space-time), leading to a way to incorporate right at the surface of the initial “space-time” bubble an uncertainty principle. From there we suggest a first principle Schrodinger equation, with the caveat that time does not exist, within the space-time nonsingular bubble, but is formed right afterwards. From there we again form solutions for strength of GW signals and suggestions as to polarization states. Our quest is motivated by our last articles question, where “We conclude by stating the following question. Can extra dimensions come from a Multiverse feed into Pre-Planckian space-time? See Theorem at the end of this publication. Our answer is in the affirmative, and it has intellectual similarities to George Chapline’s work with Black hole physics”. From there we next will in future articles postulate conditions for experimental detectors for subsequent data sets to obtain falsifiable data sets.展开更多
We reduplicate the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, given zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wave just prior to specifying the creation...We reduplicate the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, given zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wave just prior to specifying the creation of “gravitons”, while using Karen Freeze’s criteria as to the breakup of primordial black holes to give radiation era contributions to GW generation. The GW generation will be when there is sufficient early universe density so as to break apart Relic Black holes of the order of Planck mass (10<sup>15</sup> grams) which is about when the mass of relic black holes is created, 10<sup>-27</sup> or so seconds after expansion starts. Needles to state a key result will be in the initial potential V calculated, in terms of other input variables.展开更多
We are using information from a paper deriving a Lorentz-violating energy-momentum relation entailing an exact momentum cut of as stated by G. Salesi. Salesi in his work allegedly defines Pre Planckian physics, wherea...We are using information from a paper deriving a Lorentz-violating energy-momentum relation entailing an exact momentum cut of as stated by G. Salesi. Salesi in his work allegedly defines Pre Planckian physics, whereas we restrict our given application to GW generation and DE formation in the first 10<sup>-39</sup> s to 10<sup>-33</sup> s or so seconds in the early universe. This procedure is enacted due to an earlier work whereas referees exhibited puzzlement as to the physical mechanism for release of Gravitons in the very early universe. The calculation is meant to be complementary to work done in the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, and also a calculation for Black hole destruction as outlined by Karen Freeze, <i>et al</i>. The GW generation will be when there is sufficient early universe density so as to break apart Relic Black holes but we claim that this destruction is directly linked to a Lorentz violating energy-momentum G. Salesi derived, which we adopt, with a mass m added in the G. Salesi energy momentum results proportional to a tiny graviton mass, times the number of gravitons in the first 10<sup>-43</sup> seconds.展开更多
文摘Using a Linde reference, as well as another one from Padmanabhan for calculation of how the early universe expands, we obtain, by default the coefficient of scale factor expansion, t to the alpha value, with alpha being approximately the square root of five in value. We from there make an estimate as to the number of initial particles produced in the very beginning, which leads us to conclude that a graviton, would be a preferred initial by product. The argument as to gravitons, also reflects a choice of how the decay of initial BEC condensates of Planck sized black holes would commence, using the work produced by Chavanis, as to BEC condensates and black holes. The object will be to obtain initial frequency spread plus strength of GW production plus a suggestion as to what polarization state may be accessible from initial conditions.
文摘This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is not possible to read a local linear scale factor in the direction of a coordinate axis immediately from the definition of a local linear scale factor,this paper considers the derivation of new formulae that enable local linear scale factors in the direction of coordinate x and y axes to be calculated.The formula for computing the local linear scale factor in any direction defined by dx and dy is also derived.Furthermore,the position and magnitude of the extreme values of the local linear scale factor are considered and new formulas derived.
文摘Geometric or sub-scale modeling techniques are used for the evaluation of large and complex dynamic structures to ensure accurate reproduction of load path and thus leading to true dynamic characteristics of such structures. The sub-scale modeling technique is very effective in the prediction of vibration characteristics of original large structure when the experimental testing is not feasible due to the absence of a large testing facility. Previous researches were more focused on free and harmonic vibration case with little or no consideration for readily encountered random vibration. A sub-scale modeling technique is proposed for estimating the vibration characteristics of any large scale structure such as Launch vehicles, Mega structures, etc., under various vibration load cases by utilizing precise scaled-down model of that dynamic structure. In order to establish an analytical correlation between the original structure and its scaled models, different scale models of isotropic cantilever beam are selected and analyzed under various vibration conditions( i.e. free, harmonic and random) using finite element package ANSYS. The developed correlations are also validated through experimental testing The prediction made from the vibratory response of the scaled-down beam through the established sets of correlation are found similar to the response measured from the testing of original beam structure. The established correlations are equally applicable in the prediction of dynamic characteristics of any complex structure through its scaled-down models. This paper presents modified sub-scale modeling technique that enables accurate prediction of vibration characteristics of large and complex structure under not only sinusoidal but also for random vibrations.
文摘One of the crucial and challenging issues for researchers is presenting an appropriate approach to evaluate the aerodynamic characteristics of air cushion vehicles(ACVs)in terms of system design parameters.One of these issues includes introducing a suitable approach to analyze the effect of geometric shapes on the aerodynamic characteristics of ACVs.The main novelty of this paper lies in presenting an innovative method to study the geometric shape effect on air cushion lift force,which has not been investigated thus far.Moreover,this paper introduces a new approximate mathematical formula for calculating the air cushion lift force in terms of parameters,including the air gap,lateral gaps,air inlet velocity,and scaling factor for the first time.Thus,we calculate the aerodynamic lift force applied to nine different shapes of the air cushions used in the ACVs in the present paper through the ANSYS Fluent software.The geometrical shapes studied in this paper are rectangular,square,equilateral triangle,circular,elliptic shapes,and four other combined shapes,including circle-rectangle,circle-square,hexagonal,and fillet square.Results showed that the cushion with a circular pattern produces the highest lift force among other geometric shapes with the same conditions.The increase in the cushion lift force can be attributed to the fillet with a square shape and its increasing radius compared with the square shape.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61007040)
文摘In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOGs), three types of polarization-maintaining (PM) fibers are tested by using a 60Co γ-radiation source. The observed different mean wave- length shift (MWS) behaviors for different fibers are interpreted by color-center theory involving dose rate-dependent absorption bands in ultraviolet and visible ranges and total dose-dependent near-infrared absorption bands. To evaluate the mean wavelength variation in a fiber coil and the induced scale factor change for space-borne IFOGs under low radiation doses in a space environment, the influence of dose rate on the mean wavelength is investigated by testing four germanium (Ge) doped fibers and two germanium-phosphorus (Ge-P) codoped fibers irradiated at different dose rates. Experimental results indicate that the Ge-doped fibers show the least mean wavelength shift during irradiation and their mean wavelength of optical signal transmission in fibers will shift to a shorter wavelength in a low-dose-rate radiation environment. Finally, the change in the scale factor of IFOG resulting from the mean wavelength shift is estimated and tested, and it is found that the significant radiation-induced scale factor variation must be considered during the design of space-borne IFOGs.
基金Supported by National Key R&D Program of China(Grant No.2018YFB1700704).
文摘Multifdelity surrogates(MFSs)replace computationally intensive models by synergistically combining information from diferent fdelity data with a signifcant improvement in modeling efciency.In this paper,a modifed MFS(MMFS)model based on a radial basis function(RBF)is proposed,in which two fdelities of information can be analyzed by adaptively obtaining the scale factor.In the MMFS,an RBF was employed to establish the low-fdelity model.The correlation matrix of the high-fdelity samples and corresponding low-fdelity responses were integrated into an expansion matrix to determine the scaling function parameters.The shape parameters of the basis function were optimized by minimizing the leave-one-out cross-validation error of the high-fdelity sample points.The performance of the MMFS was compared with those of other MFS models(MFS-RBF and cooperative RBF)and single-fdelity RBF using four benchmark test functions,by which the impacts of diferent high-fdelity sample sizes on the prediction accuracy were also analyzed.The sensitivity of the MMFS model to the randomness of the design of experiments(DoE)was investigated by repeating sampling plans with 20 diferent DoEs.Stress analysis of the steel plate is presented to highlight the prediction ability of the proposed MMFS model.This research proposes a new multifdelity modeling method that can fully use two fdelity sample sets,rapidly calculate model parameters,and exhibit good prediction accuracy and robustness.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB05040300)the National Natural Science Foundation of China(Grant No.41205119)
文摘Estimation of random errors, which are due to shot noise of photomultiplier tube(PMT) or avalanche photodiode(APD) detectors, is very necessary in lidar observation. Due to the Poisson distribution of incident electrons, there still exists a proportional relationship between standard deviation and square root of its mean value. Based on this relationship,noise scale factor(NSF) is introduced into the estimation, which only needs a single data sample. This method overcomes the distractions of atmospheric fluctuations during calculation of random errors. The results show that this method is feasible and reliable.
基金The project supported by the National Natural Science Foundation of China (50579081)the Australian Research Council (DP0452681)The English text was polished by Keren Wang
文摘The scaled boundary finite element method (SBFEM) is a recently developed numerical method combining advantages of both finite element methods (FEM) and boundary element methods (BEM) and with its own special features as well. One of the most prominent advantages is its capability of calculating stress intensity factors (SIFs) directly from the stress solutions whose singularities at crack tips are analytically represented. This advantage is taken in this study to model static and dynamic fracture problems. For static problems, a remeshing algorithm as simple as used in the BEM is developed while retaining the generality and flexibility of the FEM. Fully-automatic modelling of the mixed-mode crack propagation is then realised by combining the remeshing algorithm with a propagation criterion. For dynamic fracture problems, a newly developed series-increasing solution to the SBFEM governing equations in the frequency domain is applied to calculate dynamic SIFs. Three plane problems are modelled. The numerical results show that the SBFEM can accurately predict static and dynamic SIFs, cracking paths and load-displacement curves, using only a fraction of degrees of freedom generally needed by the traditional finite element methods.
基金Project supported by the National Natural Science Foundation of China (Grant No 60575038)
文摘We study projective synchronization with different scaling factors (PSDF) in N coupled chaotic systems networks. By using the adaptive linear control, some sufficient criteria for the PSDF in symmetrical and asymmetrical coupled networks are separately given based on the Lyapunov function method and the left eigenvalue theory. Numerical simulations for a generalized chaotic unified system are illustrated to verify the theoretical results.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61273088,10971120,and 61001099)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2010FM010)
文摘To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes.
基金supported by the National Natural Science Foundation of China(No.42004008)the Natural Science Foundation of Jiangsu Province,China(No.BK20190498)+1 种基金the Fundamental Research Funds for the Central Universities(No.B220202055)the State Scholarship Fund from Chinese Scholarship Council(No.201306270014).
文摘The global bathymetry models are usually of low accuracy over the coastline of polar areas due to the harsh climatic environment and the complex topography.Satellite altimetric gravity data can be a supplement and plays a key role in bathymetry modeling over these regions.The Synthetic Aperture Radar(SAR)altimeters in the missions like CryoSat-2 and Sentinel-3A/3B can relieve waveform contamination that existed in conventional altimeters and provide data with improved accuracy and spatial resolution.In this study,we investigate the potential application of SAR altimetric gravity data in enhancing coastal bathymetry,where the effects on local bathymetry modeling introduced from SAR altimetry data are quantified and evaluated.Furthermore,we study the effects on bathymetry modeling by using different scale factor calculation approaches,where a partition-wise scheme is implemented.The numerical experiment over the South Sandwich Islands near Antarctica suggests that using SARbased altimetric gravity data improves local coastal bathymetry modeling,compared with the model calculated without SAR altimetry data by a magnitude of 3:55 m within 10 km of offshore areas.Moreover,by using the partition-wise scheme for scale factor calculation,the quality of the coastal bathymetry model is improved by 7.34 m compared with the result derived from the traditional method.These results indicate the superiority of using SAR altimetry data in coastal bathymetry inversion.
文摘This study aimed to deal with three challenges:robustness,imperceptibility,and capacity in the image watermarking field.To reach a high capacity,a novel similarity-based edge detection algorithm was developed that finds more edge points than traditional techniques.The colored watermark image was created by inserting a randomly generated message on the edge points detected by this algorithm.To ensure robustness and imperceptibility,watermark and cover images were combined in the high-frequency subbands using Discrete Wavelet Transform and Singular Value Decomposition.In the watermarking stage,the watermark image was weighted by the adaptive scaling factor calculated by the standard deviation of the similarity image.According to the results,the proposed edge-based color image watermarking technique has achieved high payload capacity,imperceptibility,and robustness to all attacks.In addition,the highest performance values were obtained against rotation attack,to which sufficient robustness has not been reached in the related studies.
文摘We revisit how we utilized how Weber in 1961 initiated the process of quantization of early universe fields to the issue of what was for a wormhole mouth. While the wormhole models are well understood, there is not such a consensus as to how the mouth of a wormhole could generate signals. We try to develop a model for doing so and then revisit it, the Wormhole while considering a Tokamak model we used in a different publication as a way of generating GW, and Gravitons.
基金National Natural Science Foundation of China Under Grant No. 50778058 and 90715038National Key Technology R&D Program Under Contract No. 2006BAC13B02
文摘In this paper, three existing source spectral models for stochastic finite-fault modeling of ground motion were reviewed. These three models were used to calculate the far-field received energy at a site from a vertical fault and the mean spectral ratio over 15 stations of the Northridge earthquake, and then compared. From the comparison, a necessary measure was observed to maintain the far-field received energy independent of subfault size and avoid overestimation of the long- period spectra/level. Two improvements were made to one of the three models (i.e., the model based on dynamic comer frequency) as follows: (i) a new method to compute the subfault comer frequency was proposed, where the subfault comer frequency is determined based on a basic value calculated from the total seismic moment of the entire fault and an increment depending on the seismic moment assigned to the subfault; and (ii) the difference of the radiation energy from each suhfault was considered into the scaling factor. The improved model was also compared with the unimproved model through the far-field received energy and the mean spectral ratio. The comparison proves that the improved model allows the received energy to be more independent of subfault size than the unimproved model, and decreases the overestimation degree of the long-period spectral amplitude.
基金the Natural Science Foundation of Zhejiang Province of China under Grant No.Y604056the Doctoral Foundation of Ningbo City under Grant No.2005A610030
文摘Based on symbolic computation system Maple and Lyapunov stability theory,an active control method isused to projectively synchronize two different chaotic systems—Lorenz-Chen-Lü system(LCL)and Rssler system,which belong to different dynamic systems.In this paper,we achieve generalized projective synchronization between thetwo different chaotic systems by directing the scaling factor onto the desired value arbitrarily.To illustrate our result,numerical simulations are used to perform the process of the synchronization and successfully put the orbits of drivesystem(LCL)and orbits of the response system(Rssler system)in the same plot for understanding intuitively.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFF0200103 and 2016YFF0200200)the Fundamental Research Funds for National Institute of Metrology,China(Grant No.22-AKY1608)
文摘The scale factor of a superconducting gravimeter(SG) is usually calibrated by using simultaneous and co-located gravity measurements with the FG5-type absolute gravimeter(AG). In this paper, another new kind of absolute gravimetercold atom gravimeter(CAG) is first reported to calibrate the SG. Five-day side-by-side gravity measurements have been carried out by using our CAG(NIM-AGRb-1) to calibrate the SG(iGrav-012) located at Changping Campus of the National Institute of Metrology(NIM) of China. A weighted least-squares method is applied to determine the scale factor and the result is given as(-928.01 ± 0.73) nm·s;·V;with a precision of 0.79‰. We have demonstrated that a calibration precision of 1‰ level can be achieved after 3 days of parallel observations at spring tide. The obtained calibration results are then compared with the previous calibration by FG5 X-249, which shows that the calibration precision obtained by using NIM-AGRb-1 was slightly higher than FG5 X-249 with the same time interval. The factors affecting the calibration precision are analyzed in the calibrations by means of different AGs. Finally, several calibration experiments for SG iGrav-012 are discussed. The final scale factor is estimated as(-927.58 ± 0.36) nm·s;·V;with an accuracy of 0.39‰. Our main results demonstrate that the CAGs can be used for high-precision calibrations of SGs.
文摘We reduplicate the Book “Dark Energy” by M. Li, X.-D. Li, and Y. Wang, zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wavefunction just prior to the entrance of “gravitons” to a small region of space-time prior to a nonsingular start to the universe. We compare this to a solution which worked out using Klauder Enhanced quantization, for the same given problem. The solution of the first Cosmological Constant problem relies upon the geometry of the multiverse generalization of CCC cosmology which is explained in this paper. The second solution used involves Klauder enhanced quantization. We look at energy given by our methods and compare and contrast it with the negative energy of the Rosen model for a mini sub-universe and estimate GW frequencies.
文摘Our Methodology is to construct using a “trivial” solution to massive gravitons, and a nonsingular start for expansion of the universe. Our methodology has many unintended consequences, not the least is a relationship between a small time step, t, the minimum scale factor and even the tension or property values of the initial space-time wall, and that is a consequence of a “trivial” solution taking into account “massive” gravitons. <i>I.e.</i> this solution has a mass term times the partial derivative with respect to time of an expression in brackets. The expression in brackets is the cube of a scale factor minus the square of the scale factor. Bonus that this equation is set to zero. It is deemed trivial due to the insistence of having a singular solution. If that is dropped, we have a different venue. In addition, the Friedman equation for nonsingular cosmology can have a quadratic dependence upon a density (of space-time), leading to a way to incorporate right at the surface of the initial “space-time” bubble an uncertainty principle. From there we suggest a first principle Schrodinger equation, with the caveat that time does not exist, within the space-time nonsingular bubble, but is formed right afterwards. From there we again form solutions for strength of GW signals and suggestions as to polarization states. Our quest is motivated by our last articles question, where “We conclude by stating the following question. Can extra dimensions come from a Multiverse feed into Pre-Planckian space-time? See Theorem at the end of this publication. Our answer is in the affirmative, and it has intellectual similarities to George Chapline’s work with Black hole physics”. From there we next will in future articles postulate conditions for experimental detectors for subsequent data sets to obtain falsifiable data sets.
文摘We reduplicate the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, given zero-point energy calculation with an unexpected “length” added to the “width” of a graviton wave just prior to specifying the creation of “gravitons”, while using Karen Freeze’s criteria as to the breakup of primordial black holes to give radiation era contributions to GW generation. The GW generation will be when there is sufficient early universe density so as to break apart Relic Black holes of the order of Planck mass (10<sup>15</sup> grams) which is about when the mass of relic black holes is created, 10<sup>-27</sup> or so seconds after expansion starts. Needles to state a key result will be in the initial potential V calculated, in terms of other input variables.
文摘We are using information from a paper deriving a Lorentz-violating energy-momentum relation entailing an exact momentum cut of as stated by G. Salesi. Salesi in his work allegedly defines Pre Planckian physics, whereas we restrict our given application to GW generation and DE formation in the first 10<sup>-39</sup> s to 10<sup>-33</sup> s or so seconds in the early universe. This procedure is enacted due to an earlier work whereas referees exhibited puzzlement as to the physical mechanism for release of Gravitons in the very early universe. The calculation is meant to be complementary to work done in the Book “Dark Energy” by M. Li, X-D. Li, and Y. Wang, and also a calculation for Black hole destruction as outlined by Karen Freeze, <i>et al</i>. The GW generation will be when there is sufficient early universe density so as to break apart Relic Black holes but we claim that this destruction is directly linked to a Lorentz violating energy-momentum G. Salesi derived, which we adopt, with a mass m added in the G. Salesi energy momentum results proportional to a tiny graviton mass, times the number of gravitons in the first 10<sup>-43</sup> seconds.