Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confinement fusion applications.The workhorse ...Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confinement fusion applications.The workhorse of warm dense matter theory is thermal density functional theory(DFT),which,however,suffers from two limitations:(i)its accuracy can depend on the utilized exchange-correlation functional,which has to be approximated,and(ii)it is generally limited to single-electron properties such as the density distribution.Here,we present a new ansatz combining time-dependent DFT results for the dynamic structure factor S_(ee)(q,ω)with static DFT results for the density response.This allows us to estimate the electron-electron static structure factor S_(ee)(q)of warm dense hydrogen with high accuracy over a broad range of densities and temperatures.In addition to its value for the study of warm dense matter,our work opens up new avenues for the future study of electronic correlations exclusively within the framework of DFT for a host of applications.展开更多
The Kagome metal CsV3Sb5 transitions from a weakly correlated state to a strongly correlated state upon Cr substitution;however,the mechanism driving this enhancement remains an open question.Here,we employed a combin...The Kagome metal CsV3Sb5 transitions from a weakly correlated state to a strongly correlated state upon Cr substitution;however,the mechanism driving this enhancement remains an open question.Here,we employed a combination of density functional theory and dynamical mean-field theory(DFT+DMFT)to systematically investigate the evolution of electronic correlations in the CsV_(3−x)Cr_(x)Sb_(5)(x=0,1,and 3)series.Our calculations revealed that Cr doping drives the system into a strongly correlated Hund’s metal phase,which is characterized by significant and orbital-dependent enhancements in the quasiparticle effective masses and electronic scattering rates.We trace the origin of this transition to the doping-induced shift from low-to high-spin atomic configurations.This preference for high-spin states,which is promoted by near-half-filling of the Cr-d orbitals,induces a pronounced orbital blocking effect that strengthens the correlations.Our findings establish that Hund’s coupling is the decisive factor governing the rich correlation physics in the CsV_(3−x)Cr_(x)Sb_(5) family,providing a tunable platform for exploring Hund’s metallicity.展开更多
The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice sp...The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice space and the reflection-asymmetric triaxial particle rotor model.It is found that^(229)Th has a ground state with static axial octupole and quadrupole deformations.The occurrence of octupole correlations,driven by the octupole deformation,is analyzed through the evolution of single-particle levels around the Fermi surface.The experimental energy spectrum and the electromagnetic transition probabilities,including B(E2)and B(M1),are reasonably well reproduced.展开更多
BACKGROUND Studies have shown that locomotive syndrome(LS)is significantly correlated with adverse outcomes,such as decreased self-care abilities,fractures,and increased mortality.Subthreshold depression(StD)is consid...BACKGROUND Studies have shown that locomotive syndrome(LS)is significantly correlated with adverse outcomes,such as decreased self-care abilities,fractures,and increased mortality.Subthreshold depression(StD)is considered an independent predictor of clinical depression,regarded as its prodromal stage,and even linked to increased mortality risk.Limited research has addressed the prevalence and relationship between LS and StD in elderly cancer patients.Understanding the prevalence of LS and StD among elderly cancer patients and elucidating their relationship will provide evidence to support the development of targeted interventions,thereby improving health outcomes in this population.AIM To investigate the relationship between musculoskeletal system function and predepressive states in elderly cancer patients.METHODS A convenience sampling method was employed to recruit 500 elderly cancer patients undergoing follow-up visits at the Department of Oncology,Affiliated Hospital of Jiangnan University,from April 2024 to December 2024.Participants completed the general information questionnaire, the 25-question Geriatric Locomotive Function Scale, and theGeriatric Depression Scale-Short Form-15. Influencing factors were analyzed, and correlation analyses wereperformed.RESULTSA total of 483 elderly cancer patients successfully completed the study. The prevalence of LS and StD amongparticipants was 56.5% and 38.7%, respectively. Logistic regression analysis identified age, tumor metastasis,exercise habits, and the presence of StD as significant risk factors for LS in elderly cancer patients. Additionally,having three or more chronic diseases and LS were significant predictors for developing StD. Spearman’s correlationanalysis revealed a significant positive correlation between LS and StD (r = 0.424, P < 0.001).CONCLUSIONElderly cancer patients exhibit a high prevalence of LS and StD, conditions which are positively correlated andmutually influential. Thus, it is critical to monitor and address pre-depressive states while evaluating and managingmotor function in this population.展开更多
For non-stationary complex dynamic systems,a standardized algorithm is developed to compute time correlation functions,addressing the limitations of traditional methods reliant on the stationary assumption.The propose...For non-stationary complex dynamic systems,a standardized algorithm is developed to compute time correlation functions,addressing the limitations of traditional methods reliant on the stationary assumption.The proposed algorithm integrates two-point and multi-point time correlation functions into a unified framework.Further,it is verified by a practical application in complex financial systems,demonstrating its potential in various complex dynamic systems.展开更多
BACKGROUND Psychological comorbidities,such as anxiety and depression,in patients with chronic ankle instability(CAI)may impede ankle function improvement,although the precise nature of this association warrants furth...BACKGROUND Psychological comorbidities,such as anxiety and depression,in patients with chronic ankle instability(CAI)may impede ankle function improvement,although the precise nature of this association warrants further investigation.AIM To analyze the correlation of anxiety and depression with ankle function in patients with CAI and discussing the risk factors.METHODS This study included 116 patients with CAI,who were admitted to our hospital from July 2022 to July 2024.Anxiety and depression states of patients were assessed with the self-rating anxiety scale(SAS)and self-rating depression scale(SDS),respectively,and their ankle joint function was assessed with the anklehindfoot function score of the American Orthopedic Foot and Ankle Society.Further,the ankle function of patients with CAI with different anxiety and depression states was discussed.Furthermore,the Pearson correlation coefficient was used to analyze the correlation of anxiety and depression with ankle joint function in such patients.Univariate and multivariate analyses were conducted to investigate the factors affecting ankle joint function in patients with CAI.RESULTS Among the 116 patients with CAI,97,13,5,and 1 cases demonstrated none,mild,moderate,and severe anxiety,whereas 95,15,6,and 0 cases showed none,mild,moderate,and severe depression,respectively.The average ankle joint function score was 74.82±6.93 points.The ankle joint function in patients with CAI presented a significant downward tendency as the degree of anxiety and depression increased.Correlation analysis revealed that both the SAS and SDS scores of patients with CAI were significantly negatively correlated with the ankle joint function score.Univariate and multivariate analyses indicated that the risk factors affecting patients’ankle joint function included early functional rehabilitation,visual analog scale,and SDS.CONCLUSION A substantial number of patients with CAI suffer from anxiety and depression,and these negative emotions,to a certain extent,harm the smooth rehabilitation of ankle joint function.展开更多
Establishing the structure-property relationship in amorphous materials has been a long-term grand challenge due to the lack of a unified description of the degree of disorder.In this work,we develop SPRamNet,a neural...Establishing the structure-property relationship in amorphous materials has been a long-term grand challenge due to the lack of a unified description of the degree of disorder.In this work,we develop SPRamNet,a neural network based machine-learning pipeline that effectively predicts structure-property relationship of amorphous material via global descriptors.Applying SPRamNet on the recently discovered amorphous monolayer carbon,we successfully predict the thermal and electronic properties.More importantly,we reveal that a short range of pair correlation function can readily encode sufficiently rich information of the structure of amorphous material.Utilizing powerful machine learning architectures,the encoded information can be decoded to reconstruct macroscopic properties involving many-body and long-range interactions.Establishing this hidden relationship offers a unified description of the degree of disorder and eliminates the heavy burden of measuring atomic structure,opening a new avenue in studying amorphous materials.展开更多
By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlatio...By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlation. We found that, when the correlation time between the two noises is very short, the behavior of the intensity correlation function versus the time, in addition to decreasing monotonously, also exhibits several cases, such as one maximum, one minimum, and two extrema. When the correlation time between the two noises is very long, the behavior of the intensity correlation function exhibits oscillation and the envelope is similar to the case of short cross-correlation time.展开更多
As the differences of sensor＇s precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery...As the differences of sensor＇s precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn＇t require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor＇s own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement.展开更多
Long-time cross correlation of ambient noise has been proved as a powerful tool to extract Green＇s function between two receivers. The study of composition of ambient noise is important for a better understanding of ...Long-time cross correlation of ambient noise has been proved as a powerful tool to extract Green＇s function between two receivers. The study of composition of ambient noise is important for a better understanding of this method. Previous studies confirm that ambient noise in the long period （3 s and longer） mostly consists of surface wave, and 0.25-2.5 s noise consists more of body waves. In this paper, we perform cross correlation processing at much higher frequency （30-70 Hz） using ambient noise recorded by a small aperture array. No surface waves emerge from noise correlation function （NCF）, but weak P waves emerge. The absence of surface wave in NCF is not due to high attenuation since surface waves are strong from active source, therefore probably the high ambient noise mostly consists of body wave and lacks surface wave. Origin of such high frequency body waves in ambient noise remains to be studied.展开更多
The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied systematically.Assuming a spherical Gaussian source with space and time profile according to t...The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied systematically.Assuming a spherical Gaussian source with space and time profile according to the function S(r,t)~exp(-r2/2 r02-t/τ)in the correlation function calculation code(CRAB),the results indicate that one Cpp(q)distribution corresponds to a unique combination of source size r0 and emission timeτ.Considering the possible nuclear deformation from a spherical nucleus,an ellipsoidal Gaussian source characterized by the deformation parameter∈=ΔR/R has been simulated.There is almost no difference of Cpp(q)between the results of spherically and ellipsoidally shaped sources with small deformation.These results indicate that a unique source size r0 and emission time could be extracted from the p-p momentum correlation function,which is especially important for identifying the mechanism of twoproton emission from proton-rich nuclei.Furthermore,considering the possible existence of cluster structures within a nucleus,the double Gaussian source is assumed.The results show that the p-p momentum correlation function for a source with or without cluster structures has large systematical differences with the variance of r0 andτ.This may provide a possible method for experimentally observing the cluster structures in proton-rich nuclei.展开更多
We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlati...We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other.展开更多
Blind separation of source signals usually relies either on the condition of statistically independence or involving their higher-order cumulants. The model of two channels signal separation is considered. A criterion...Blind separation of source signals usually relies either on the condition of statistically independence or involving their higher-order cumulants. The model of two channels signal separation is considered. A criterion based on correlation functions is proposed. It is proved that the signals can be separated, using only the condition of noncorrelation. An algorithm is derived, which only involves the solution to quadric nonlinear equations.展开更多
Using the linear approximation method, we have studied how the correlation function C（t） of the laser intensity changes with time in the loss-noise model of the single-mode laser driven by the colored pump noise wit...Using the linear approximation method, we have studied how the correlation function C（t） of the laser intensity changes with time in the loss-noise model of the single-mode laser driven by the colored pump noise with signal modulation and the quantum noise with cross-correlation between the real and imaginary parts. We have found that when the pump noise self-correlation time T changes, （i） in the case of r 〈〈 1, the C（t） vs. t curve experiences a changing process from the monotonous descending to monotonous rise, and finally to the appearance of a maximum; （ii） in the case of r 〉〉 1, the curve only exhibits periodically surging with descending envelope. When r 〈〈 i and T does not change, with the increase of the pump noise intensity P, the curve experiences a repeated changing process, that is, from the monotonous descending to the appearance of a maximum, then to monotonous rise, and finally to the appearance of a maximum again. With the increase of the quantum noise intensity O,, the curve experiences a changing process from the monotonous rise to the appearance of a maximum, and finally to the monotonous descending. The increase of the quantum noise with cross-correlation between the real and imaginary parts will lead to the fall of the whole curve, but not affect the form of the time evolution of C（t）.展开更多
Noise correlation function （NCF） was calculated using the data of the Beijing Capital-Area Telemetered Digital Seismograph Network from June 12 to September 12, 2005. Signal-to-noise ratio （SNR） is used to charact...Noise correlation function （NCF） was calculated using the data of the Beijing Capital-Area Telemetered Digital Seismograph Network from June 12 to September 12, 2005. Signal-to-noise ratio （SNR） is used to characterize the quality of NCF at each station pair. The SNR （in dB） is shown to be dependent on the separation distance R of the station pair via SNR= A -BlogR. ＇Normalized average SNR＇ for all the station pairs can then be calculated, as represented by the value of SNR taking R = 250 km in the empirical SNR-R relation, to measure the overall quality of the NCF result. The ＇normalized average SNR＇ of the NCF shows temporal variation and is apparently dependent on the root-mean-square （RMS） velocity of the microseism. The result obtained by this experiment provides clues to the explanation of the properties of NCF, such as the dominant mechanism underlying （diffuse wave fields or uncorrelated sources）, and the dependence of SNR on the time length of recordings.展开更多
In most of real operational conditions only response data are measurable while the actual excitations are unknown, so modal parameter must be extracted only from responses. This paper gives a theoretical formulation f...In most of real operational conditions only response data are measurable while the actual excitations are unknown, so modal parameter must be extracted only from responses. This paper gives a theoretical formulation for the cross-correlation functions and cross-power spectra between the outputs under the assumption of white-noise excitation. It widens the field of modal analysis under ambient excitation because many classical methods by impulse response functions or frequency response functions can be used easily for modal analysis under unknown excitation. The Polyreference Complex Exponential method and Eigensystem Realization Algorithm using cross-correlation functions in time domain and Orthogonal Polynomial method using cross-power spectra in frequency domain are applied to a steel frame to extract modal parameters under operational conditions. The modal properties of the steel frame from these three methods are compared with those from frequency response functions analysis. The results show that the modal analysis method using cross-correlation functions or cross-power spectra presented in this paper can extract modal parameters efficiently under unknown excitation.展开更多
In order to solve the problem of ambiguous acquisition of BOC signals caused by its property of multiple peaks,an unambiguous acquisition algorithm named reconstruction of sub cross-correlation cancellation technique(...In order to solve the problem of ambiguous acquisition of BOC signals caused by its property of multiple peaks,an unambiguous acquisition algorithm named reconstruction of sub cross-correlation cancellation technique(RSCCT)for BOC(kn,n)signals is proposed.In this paper,the principle of signal decomposition is combined with the traditional acquisition algorithm structure,and then based on the method of reconstructing the correlation function.The method firstly gets the sub-pseudorandom noise(PRN)code by decomposing the local PRN code,then uses BOC(kn,n)and the sub-PRN code cross-correlation to get the sub cross-correlation function.Finally,the correlation peak with a single peak is obtained by reconstructing the sub cross-correlation function so that the ambiguities of BOC acquisition are removed.The simulation shows that RSCCT can completely eliminate the side peaks of BOC(kn,n)group signals while maintaining the narrow correlation of BOC,and its computational complexity is equivalent to sub carrier phase cancellation(SCPC)and autocorrelation side-peak cancellation technique(ASPeCT),and it reduces the computational complexity relative to BPSK-like.For BOC(n,n),the acquisition sensitivity of RSCCT is 3.25 dB,0.81 dB and 0.25 dB higher than binary phase shift keying(BPSK)-like,SCPC and ASPeCT at the acquisition probability of 90%,respectively.The peak to average power ratio is 1.91,3.0 and 3.7 times higher than ASPeCT,SCPC and BPSK-like at SNR=–20 dB,respectively.For BOC(2n,n),the acquisition sensitivity of RSCCT is 5.5 dB,1.25 dB and 2.69 dB higher than BPSK-like,SCPC and ASPeCT at the acquisition probability of 90%,respectively.The peak to average power ratio is 1.02,1.68 and 2.12 times higher than ASPeCT,SCPC and BPSK-like at SNR=–20 dB,respectively.展开更多
Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalize...Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained.展开更多
In the paper we use detrended cross-correlation analysis （DCCA） to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads o...In the paper we use detrended cross-correlation analysis （DCCA） to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads of a healthy young subject is larger than that of a healthy old subject. It was shown that the cross-correlation relationship decreases with the aging process and the phenomenon can help to diagnose whether the subject＇s brain function is healthy or not.展开更多
The sequences with good correlation properties are widely used in engineering applications, especially in the area of communications. In this paper, the relationships among crosscorrelation functions of arbitrary four...The sequences with good correlation properties are widely used in engineering applications, especially in the area of communications. In this paper, the relationships among crosscorrelation functions of arbitrary four binary sequences of period N are presented. Based on them, for a sequences set, the relationships between cross-correlation functions and autocorrelation functions are studied, by which we prove that they cannot keep optimal at the same time.展开更多
基金partially supported by the Center for Advanced Systems Understanding (CASUS), financed by Germany’s Federal Ministry of Education and Research and the Saxon State Government out of the State Budget approved by the Saxon State Parliamentthe European Union’s Just Transition Fund (JTF) within the project Röntgenlaser Optimierung der Laserfusion (ROLF), Contract No. 5086999001, co-financed by the Saxon State Government out of the State Budget approved by the Saxon State Parliament+3 种基金the European Research Council (ERC) under the European Union’s Horizon 2022 Research and Innovation Programme (Grant Agreement No. 101076233, “PREXTREME”)Computations were performed on a Bull Cluster at the Center for Information Services and High-Performance Computing (ZIH) at Technische Universität Dresden and at the Norddeutscher Verbund für Hoch- und Höchstleistungsrechnen (HLRN) under Grant No. mvp00024support by the National Natural Science Foundation of China under Grant No. 12274171support by the Advanced Materials–National Science and Technology Major Project (Grant No. 2024ZD0606900)
文摘Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confinement fusion applications.The workhorse of warm dense matter theory is thermal density functional theory(DFT),which,however,suffers from two limitations:(i)its accuracy can depend on the utilized exchange-correlation functional,which has to be approximated,and(ii)it is generally limited to single-electron properties such as the density distribution.Here,we present a new ansatz combining time-dependent DFT results for the dynamic structure factor S_(ee)(q,ω)with static DFT results for the density response.This allows us to estimate the electron-electron static structure factor S_(ee)(q)of warm dense hydrogen with high accuracy over a broad range of densities and temperatures.In addition to its value for the study of warm dense matter,our work opens up new avenues for the future study of electronic correlations exclusively within the framework of DFT for a host of applications.
基金supported by the Development Program of China and the National Key Research (Grant Nos.2023YFA1406200 and 2022YFA1402304)the National Natural Science Foundation of China (Grant Nos.12274169 and 12122405)+3 种基金the Fundamental Research Funds for the Central Universitiesthe Innovation Team for Functional Materials and Devices for Informatics at Anhui Higher Education Institutes (Grant No.2024AH010024)the Natural Science Research Project of Education Department of Anhui Province (Grant No.2025AHGXZK31203)the PHD Research Startup Foundation of Fuyang Normal University (Grant No.2025KYQD0072)。
文摘The Kagome metal CsV3Sb5 transitions from a weakly correlated state to a strongly correlated state upon Cr substitution;however,the mechanism driving this enhancement remains an open question.Here,we employed a combination of density functional theory and dynamical mean-field theory(DFT+DMFT)to systematically investigate the evolution of electronic correlations in the CsV_(3−x)Cr_(x)Sb_(5)(x=0,1,and 3)series.Our calculations revealed that Cr doping drives the system into a strongly correlated Hund’s metal phase,which is characterized by significant and orbital-dependent enhancements in the quasiparticle effective masses and electronic scattering rates.We trace the origin of this transition to the doping-induced shift from low-to high-spin atomic configurations.This preference for high-spin states,which is promoted by near-half-filling of the Cr-d orbitals,induces a pronounced orbital blocking effect that strengthens the correlations.Our findings establish that Hund’s coupling is the decisive factor governing the rich correlation physics in the CsV_(3−x)Cr_(x)Sb_(5) family,providing a tunable platform for exploring Hund’s metallicity.
基金supported by the National Natural Science Foundation of China(Grant Nos.12205097,12141501,12475117,and 12435006)the National Key Laboratory of Neutron Science and Technology(Grant No.NST202401016)+1 种基金the National Key R&D Program of China(Grant Nos.2024YFA1612600 and 2024YFE0109803)the High-performance Computing Platform of Peking University。
文摘The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice space and the reflection-asymmetric triaxial particle rotor model.It is found that^(229)Th has a ground state with static axial octupole and quadrupole deformations.The occurrence of octupole correlations,driven by the octupole deformation,is analyzed through the evolution of single-particle levels around the Fermi surface.The experimental energy spectrum and the electromagnetic transition probabilities,including B(E2)and B(M1),are reasonably well reproduced.
基金Supported by Wuxi Institute of Translational Medicine Project Program,No.LCYJ202336the Scientific and Technological Achievements Promotion Project of Wuxi Municipal Health Commission Project Program,No.T202336+1 种基金the Hospital Management Innovation Research Project of Jiangsu Hospital Association,No.JSYGY-3-2024-601Jiangsu Provincial Traditional Chinese Medicine Science and Technology Development Plan Project,No.MS2024063.
文摘BACKGROUND Studies have shown that locomotive syndrome(LS)is significantly correlated with adverse outcomes,such as decreased self-care abilities,fractures,and increased mortality.Subthreshold depression(StD)is considered an independent predictor of clinical depression,regarded as its prodromal stage,and even linked to increased mortality risk.Limited research has addressed the prevalence and relationship between LS and StD in elderly cancer patients.Understanding the prevalence of LS and StD among elderly cancer patients and elucidating their relationship will provide evidence to support the development of targeted interventions,thereby improving health outcomes in this population.AIM To investigate the relationship between musculoskeletal system function and predepressive states in elderly cancer patients.METHODS A convenience sampling method was employed to recruit 500 elderly cancer patients undergoing follow-up visits at the Department of Oncology,Affiliated Hospital of Jiangnan University,from April 2024 to December 2024.Participants completed the general information questionnaire, the 25-question Geriatric Locomotive Function Scale, and theGeriatric Depression Scale-Short Form-15. Influencing factors were analyzed, and correlation analyses wereperformed.RESULTSA total of 483 elderly cancer patients successfully completed the study. The prevalence of LS and StD amongparticipants was 56.5% and 38.7%, respectively. Logistic regression analysis identified age, tumor metastasis,exercise habits, and the presence of StD as significant risk factors for LS in elderly cancer patients. Additionally,having three or more chronic diseases and LS were significant predictors for developing StD. Spearman’s correlationanalysis revealed a significant positive correlation between LS and StD (r = 0.424, P < 0.001).CONCLUSIONElderly cancer patients exhibit a high prevalence of LS and StD, conditions which are positively correlated andmutually influential. Thus, it is critical to monitor and address pre-depressive states while evaluating and managingmotor function in this population.
基金Project supported by the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(Grant No.GZC20231050)the National Natural Science Foundation of China(Grant Nos.12175193 and 11905183)the 13th Five-year plan for Education Science Funding of Guangdong Province(Grant No.2021GXJK349)。
文摘For non-stationary complex dynamic systems,a standardized algorithm is developed to compute time correlation functions,addressing the limitations of traditional methods reliant on the stationary assumption.The proposed algorithm integrates two-point and multi-point time correlation functions into a unified framework.Further,it is verified by a practical application in complex financial systems,demonstrating its potential in various complex dynamic systems.
文摘BACKGROUND Psychological comorbidities,such as anxiety and depression,in patients with chronic ankle instability(CAI)may impede ankle function improvement,although the precise nature of this association warrants further investigation.AIM To analyze the correlation of anxiety and depression with ankle function in patients with CAI and discussing the risk factors.METHODS This study included 116 patients with CAI,who were admitted to our hospital from July 2022 to July 2024.Anxiety and depression states of patients were assessed with the self-rating anxiety scale(SAS)and self-rating depression scale(SDS),respectively,and their ankle joint function was assessed with the anklehindfoot function score of the American Orthopedic Foot and Ankle Society.Further,the ankle function of patients with CAI with different anxiety and depression states was discussed.Furthermore,the Pearson correlation coefficient was used to analyze the correlation of anxiety and depression with ankle joint function in such patients.Univariate and multivariate analyses were conducted to investigate the factors affecting ankle joint function in patients with CAI.RESULTS Among the 116 patients with CAI,97,13,5,and 1 cases demonstrated none,mild,moderate,and severe anxiety,whereas 95,15,6,and 0 cases showed none,mild,moderate,and severe depression,respectively.The average ankle joint function score was 74.82±6.93 points.The ankle joint function in patients with CAI presented a significant downward tendency as the degree of anxiety and depression increased.Correlation analysis revealed that both the SAS and SDS scores of patients with CAI were significantly negatively correlated with the ankle joint function score.Univariate and multivariate analyses indicated that the risk factors affecting patients’ankle joint function included early functional rehabilitation,visual analog scale,and SDS.CONCLUSION A substantial number of patients with CAI suffer from anxiety and depression,and these negative emotions,to a certain extent,harm the smooth rehabilitation of ankle joint function.
基金supported by the National Key R&D Program of China under Grant No.2021YFA1400500the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No.XDB33000000+1 种基金the National Natural Science Foundation of China under Grant No.12334003the Beijing Municipal Natural Science Foundation under Grant Nos.JQ22001 and QY23014。
文摘Establishing the structure-property relationship in amorphous materials has been a long-term grand challenge due to the lack of a unified description of the degree of disorder.In this work,we develop SPRamNet,a neural network based machine-learning pipeline that effectively predicts structure-property relationship of amorphous material via global descriptors.Applying SPRamNet on the recently discovered amorphous monolayer carbon,we successfully predict the thermal and electronic properties.More importantly,we reveal that a short range of pair correlation function can readily encode sufficiently rich information of the structure of amorphous material.Utilizing powerful machine learning architectures,the encoded information can be decoded to reconstruct macroscopic properties involving many-body and long-range interactions.Establishing this hidden relationship offers a unified description of the degree of disorder and eliminates the heavy burden of measuring atomic structure,opening a new avenue in studying amorphous materials.
文摘By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlation. We found that, when the correlation time between the two noises is very short, the behavior of the intensity correlation function versus the time, in addition to decreasing monotonously, also exhibits several cases, such as one maximum, one minimum, and two extrema. When the correlation time between the two noises is very long, the behavior of the intensity correlation function exhibits oscillation and the envelope is similar to the case of short cross-correlation time.
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2007AA04Z433)Hunan Provincial Natural Science Foundation of China (Grant No. 09JJ8005)Scientific Research Foundation of Graduate School of Beijing University of Chemical and Technology,China (Grant No. 10Me002)
文摘As the differences of sensor＇s precision and some random factors are difficult to control,the actual measurement signals are far from the target signals that affect the reliability and precision of rotating machinery fault diagnosis.The traditional signal processing methods,such as classical inference and weighted averaging algorithm usually lack dynamic adaptability that is easy for trends to cause the faults to be misjudged or left out.To enhance the measuring veracity and precision of vibration signal in rotary machine multi-sensor vibration signal fault diagnosis,a novel data level fusion approach is presented on the basis of correlation function analysis to fast determine the weighted value of multi-sensor vibration signals.The approach doesn＇t require knowing the prior information about sensors,and the weighted value of sensors can be confirmed depending on the correlation measure of real-time data tested in the data level fusion process.It gives greater weighted value to the greater correlation measure of sensor signals,and vice versa.The approach can effectively suppress large errors and even can still fuse data in the case of sensor failures because it takes full advantage of sensor＇s own-information to determine the weighted value.Moreover,it has good performance of anti-jamming due to the correlation measures between noise and effective signals are usually small.Through the simulation of typical signal collected from multi-sensors,the comparative analysis of dynamic adaptability and fault tolerance between the proposed approach and traditional weighted averaging approach is taken.Finally,the rotor dynamics and integrated fault simulator is taken as an example to verify the feasibility and advantages of the proposed approach,it is shown that the multi-sensor data level fusion based on correlation function weighted approach is better than the traditional weighted average approach with respect to fusion precision and dynamic adaptability.Meantime,the approach is adaptable and easy to use,can be applied to other areas of vibration measurement.
基金supported by Central Public-interest Scientific Institution Basal Research Fund (No. DQJB09B07)Knowledge Innovation Program of the Chinese Academy of Sciences under grant No. KZCX2-YW-116-1+1 种基金supported partially by National Natural Science Foundation of China (Nos. 40874095, 40730318 and 41004019)China Earthquake Administration Special Program Fund (Nos. 200808078 and 200808002)
文摘Long-time cross correlation of ambient noise has been proved as a powerful tool to extract Green＇s function between two receivers. The study of composition of ambient noise is important for a better understanding of this method. Previous studies confirm that ambient noise in the long period （3 s and longer） mostly consists of surface wave, and 0.25-2.5 s noise consists more of body waves. In this paper, we perform cross correlation processing at much higher frequency （30-70 Hz） using ambient noise recorded by a small aperture array. No surface waves emerge from noise correlation function （NCF）, but weak P waves emerge. The absence of surface wave in NCF is not due to high attenuation since surface waves are strong from active source, therefore probably the high ambient noise mostly consists of body wave and lacks surface wave. Origin of such high frequency body waves in ambient noise remains to be studied.
基金supported by the National Key R&D Program of China(No.2018YFA0404404)the National Natural Science Foundation of China(Nos.11925502,11935001,11961141003,11421505,11475244,and 11927901)+2 种基金the Shanghai Development Foundation for Science and Technology(No.19ZR1403100)the Strategic Priority Research Program of the CAS(No.XDB34030000)the Key Research Program of Frontier Sciences of the CAS(No.QYZDJ-SSW-SLH002).
文摘The effect of source size and emission time on the proton-proton(p-p)momentum correlation function(Cpp(q))has been studied systematically.Assuming a spherical Gaussian source with space and time profile according to the function S(r,t)~exp(-r2/2 r02-t/τ)in the correlation function calculation code(CRAB),the results indicate that one Cpp(q)distribution corresponds to a unique combination of source size r0 and emission timeτ.Considering the possible nuclear deformation from a spherical nucleus,an ellipsoidal Gaussian source characterized by the deformation parameter∈=ΔR/R has been simulated.There is almost no difference of Cpp(q)between the results of spherically and ellipsoidally shaped sources with small deformation.These results indicate that a unique source size r0 and emission time could be extracted from the p-p momentum correlation function,which is especially important for identifying the mechanism of twoproton emission from proton-rich nuclei.Furthermore,considering the possible existence of cluster structures within a nucleus,the double Gaussian source is assumed.The results show that the p-p momentum correlation function for a source with or without cluster structures has large systematical differences with the variance of r0 andτ.This may provide a possible method for experimentally observing the cluster structures in proton-rich nuclei.
文摘We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other.
文摘Blind separation of source signals usually relies either on the condition of statistically independence or involving their higher-order cumulants. The model of two channels signal separation is considered. A criterion based on correlation functions is proposed. It is proved that the signals can be separated, using only the condition of noncorrelation. An algorithm is derived, which only involves the solution to quadric nonlinear equations.
文摘Using the linear approximation method, we have studied how the correlation function C（t） of the laser intensity changes with time in the loss-noise model of the single-mode laser driven by the colored pump noise with signal modulation and the quantum noise with cross-correlation between the real and imaginary parts. We have found that when the pump noise self-correlation time T changes, （i） in the case of r 〈〈 1, the C（t） vs. t curve experiences a changing process from the monotonous descending to monotonous rise, and finally to the appearance of a maximum; （ii） in the case of r 〉〉 1, the curve only exhibits periodically surging with descending envelope. When r 〈〈 i and T does not change, with the increase of the pump noise intensity P, the curve experiences a repeated changing process, that is, from the monotonous descending to the appearance of a maximum, then to monotonous rise, and finally to the appearance of a maximum again. With the increase of the quantum noise intensity O,, the curve experiences a changing process from the monotonous rise to the appearance of a maximum, and finally to the monotonous descending. The increase of the quantum noise with cross-correlation between the real and imaginary parts will lead to the fall of the whole curve, but not affect the form of the time evolution of C（t）.
基金supported by the Fundamental Research and Development of Institute of Geophysics,China Earthquake Administration (DQJB07B03)
文摘Noise correlation function （NCF） was calculated using the data of the Beijing Capital-Area Telemetered Digital Seismograph Network from June 12 to September 12, 2005. Signal-to-noise ratio （SNR） is used to characterize the quality of NCF at each station pair. The SNR （in dB） is shown to be dependent on the separation distance R of the station pair via SNR= A -BlogR. ＇Normalized average SNR＇ for all the station pairs can then be calculated, as represented by the value of SNR taking R = 250 km in the empirical SNR-R relation, to measure the overall quality of the NCF result. The ＇normalized average SNR＇ of the NCF shows temporal variation and is apparently dependent on the root-mean-square （RMS） velocity of the microseism. The result obtained by this experiment provides clues to the explanation of the properties of NCF, such as the dominant mechanism underlying （diffuse wave fields or uncorrelated sources）, and the dependence of SNR on the time length of recordings.
基金Item of the 9-th F ive Plan of the Aeronautical Industrial Corporation
文摘In most of real operational conditions only response data are measurable while the actual excitations are unknown, so modal parameter must be extracted only from responses. This paper gives a theoretical formulation for the cross-correlation functions and cross-power spectra between the outputs under the assumption of white-noise excitation. It widens the field of modal analysis under ambient excitation because many classical methods by impulse response functions or frequency response functions can be used easily for modal analysis under unknown excitation. The Polyreference Complex Exponential method and Eigensystem Realization Algorithm using cross-correlation functions in time domain and Orthogonal Polynomial method using cross-power spectra in frequency domain are applied to a steel frame to extract modal parameters under operational conditions. The modal properties of the steel frame from these three methods are compared with those from frequency response functions analysis. The results show that the modal analysis method using cross-correlation functions or cross-power spectra presented in this paper can extract modal parameters efficiently under unknown excitation.
基金supported by the National Science Foundation of China(61561016 61861008+4 种基金 11603041)the Guangxi Natural Science Foundation Project(2018JJA170090)the Innovation Project of Guet Graduate Education(2018YJCX19 2018YJCX31)Guangxi Key Laboratory of Precision Navigation Technology and Application,Guilin University of Electronic Technology(DH201707)
文摘In order to solve the problem of ambiguous acquisition of BOC signals caused by its property of multiple peaks,an unambiguous acquisition algorithm named reconstruction of sub cross-correlation cancellation technique(RSCCT)for BOC(kn,n)signals is proposed.In this paper,the principle of signal decomposition is combined with the traditional acquisition algorithm structure,and then based on the method of reconstructing the correlation function.The method firstly gets the sub-pseudorandom noise(PRN)code by decomposing the local PRN code,then uses BOC(kn,n)and the sub-PRN code cross-correlation to get the sub cross-correlation function.Finally,the correlation peak with a single peak is obtained by reconstructing the sub cross-correlation function so that the ambiguities of BOC acquisition are removed.The simulation shows that RSCCT can completely eliminate the side peaks of BOC(kn,n)group signals while maintaining the narrow correlation of BOC,and its computational complexity is equivalent to sub carrier phase cancellation(SCPC)and autocorrelation side-peak cancellation technique(ASPeCT),and it reduces the computational complexity relative to BPSK-like.For BOC(n,n),the acquisition sensitivity of RSCCT is 3.25 dB,0.81 dB and 0.25 dB higher than binary phase shift keying(BPSK)-like,SCPC and ASPeCT at the acquisition probability of 90%,respectively.The peak to average power ratio is 1.91,3.0 and 3.7 times higher than ASPeCT,SCPC and BPSK-like at SNR=–20 dB,respectively.For BOC(2n,n),the acquisition sensitivity of RSCCT is 5.5 dB,1.25 dB and 2.69 dB higher than BPSK-like,SCPC and ASPeCT at the acquisition probability of 90%,respectively.The peak to average power ratio is 1.02,1.68 and 2.12 times higher than ASPeCT,SCPC and BPSK-like at SNR=–20 dB,respectively.
基金Supported by State Key Laboratory of InformationSecurity Opening Foundation(01-02) .
文摘Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained.
基金supported by the Science Foundation of Jiangsu Province of China (Grant No.BK2011759)
文摘In the paper we use detrended cross-correlation analysis （DCCA） to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads of a healthy young subject is larger than that of a healthy old subject. It was shown that the cross-correlation relationship decreases with the aging process and the phenomenon can help to diagnose whether the subject＇s brain function is healthy or not.
基金Supported by the Natural Science Foundation of Anhui(1608085MF143)the National Natural Science Foundation of China(60573026,10101008)the Natural Science Foundation of Anhui Higher Education Institutions of China(KJ2018A0678)
文摘The sequences with good correlation properties are widely used in engineering applications, especially in the area of communications. In this paper, the relationships among crosscorrelation functions of arbitrary four binary sequences of period N are presented. Based on them, for a sequences set, the relationships between cross-correlation functions and autocorrelation functions are studied, by which we prove that they cannot keep optimal at the same time.
