The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female populat...The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was constructed.Considering backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel phantom.Image acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray spectra.We calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was investigated.The D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in China.The difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth direction.The results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.展开更多
The exact classical limits for the coefficient of variation c for the normal distribution are derived. The hand-calculating approximated classical limits for c having high accuracy are given to meet practical engineer...The exact classical limits for the coefficient of variation c for the normal distribution are derived. The hand-calculating approximated classical limits for c having high accuracy are given to meet practical engineering needs. Using Odeh and Owen's computational method and Brent's algorithm, the tables for the r-upper exact classical limits of coefficient of variation for normal distribution are calculated for the different confidence coefficient y, the sample size n=1(1)30,40,60,120, the sample coefficient of variation c=0.01(0.01)0.20. It is shown that if n<8,c<0.20, then the V -upper exact classical limits cu for c are slightly higher than the exact fiducial limits cu,F for c if. n>8, c<0.02,then cu-cu,f<5x10-6展开更多
OBJECTIVE:To establish a quantification model of Traditional Chinese Medicine(TCM)syndromes by sampling patients undergoing idiopathic precocious puberty(IPP)and early puberty.METHODS:A questionnaire for classifying a...OBJECTIVE:To establish a quantification model of Traditional Chinese Medicine(TCM)syndromes by sampling patients undergoing idiopathic precocious puberty(IPP)and early puberty.METHODS:A questionnaire for classifying and quantifying TCM syndromes was designed and administered.All the results were analyzed;the relationship between 3 types of syndrome and 47symptoms were summated.Meanwhile,the frequency distribution of each symptom or sign was aggregated.Fuzzy mathematics was used to develop a quantification model ofTCM syndromes.RESULTS:We found that precocious puberty had 3types of syndrome,including hyperactivity of fire due to Yin deficiency(Syndrome I),depressed liver Qi transforming into fire(Syndrome II),and end retention of damp heat(Syndrome III).In the IPP group,Syndrome I was the most common principal syndrome(100%).Forty-six patients(43.81%)werediagnosed with Syndrome I accompanied by Syndrome II and 11(10.48%)were diagnosed with Syndrome I accompanied by Syndrome III.In the early puberty group,Syndrome I was also the main syndrome(98.39%).The degrees of most symptoms were mild to moderate.Reddened tongue was the most common tongue manifestation(62.86%prevalence)in the IPP group.The most common pulse manifestations were slippery pulse,thread pulse,and taut pulse.The Asymptotic Normalization Coefficient(ANC)method was used to quantify the TCM syndromes in 167 cases.Diagnostic accuracy rate reached 91%,comparable to expert diagnosis.CONCLUSION:We find that there are 3 types of syndrome in the IPP group and in the early puberty group.Syndrome I(hyperactivity of fire due to Yin deficiency)is the main syndrome in the two groups.ANC may be an appropriate for quantification model ofTCM syndromes.展开更多
Due to the presence of non-stationarities and discontinuities in the audio signal, segmentation and classification of audio signal is a really challenging task. Automatic music classification and annotation is still c...Due to the presence of non-stationarities and discontinuities in the audio signal, segmentation and classification of audio signal is a really challenging task. Automatic music classification and annotation is still considered as a challenging task due to the difficulty of extracting and selecting the optimal audio features. Hence, this paper proposes an efficient approach for segmentation, feature extraction and classification of audio signals. Enhanced Mel Frequency Cepstral Coefficient (EMFCC)-Enhanced Power Normalized Cepstral Coefficients (EPNCC) based feature extraction is applied for the extraction of features from the audio signal. Then, multi-level classification is done to classify the audio signal as a musical or non-musical signal. The proposed approach achieves better performance in terms of precision, Normalized Mutual Information (NMI), F-score and entropy. The PNN classifier shows high False Rejection Rate (FRR), False Acceptance Rate (FAR), Genuine Acceptance rate (GAR), sensitivity, specificity and accuracy with respect to the number of classes.展开更多
The radionuclide 22Na generates the emission of a characteristic 1.275 MeVγ-ray.This is a potential astronomical observable,whose occurrence is suspected in classical novae.The 22Mg(p,γ)23Al reaction is relevant to ...The radionuclide 22Na generates the emission of a characteristic 1.275 MeVγ-ray.This is a potential astronomical observable,whose occurrence is suspected in classical novae.The 22Mg(p,γ)23Al reaction is relevant to the nucleosynthesis of 22Na in Ne-rich novae.In this study,employing the adiabatic distorted wave approximation and continuum discretized coupled channel methods,the squared neutron asymptotic normalization coefficients(ANCs)231 for the virtual decay of Ne→22Ne+n were extracted,and determined as(0.483±0.060)fm-1 and(9.7±2.3)fm-1 for the ground state and the first excited state from the experimental angular distributions of 22Ne(d,p)23Ne populating the ground state and the first excited state of 23Ne,respectively.Then,the squared proton ANC of 23Alg.s.was obtained as Cd5/22(23Al)(2.65±0.33)×103 fm-1 according to the charge symmetry of the strong interaction.The astrophysical S-factors and reaction rates for the direct capture contribution in 22Mg(p,γ)23Al were also presented.Furthermore,the proton width of the first excited state of 23Al was derived to be(57±14)eV from the neutron ANC of its mirror state in 23Ne and used to compute the contribution from the first resonance of 23Al.This result demonstrates that the direct capture dominates the 22Mg(p,γ)23Al reaction at most temperatures of astrophysical relevance for 0.33<T9<0.64.展开更多
The asymptotic normalization coefficients （ANCs） of the virtual decay 16N -- 15N ＋ n are extracted from the 15N（7Li, 6Li）16N reaction populating the ground and first three excited states in 16N. The root-mean-squ...The asymptotic normalization coefficients （ANCs） of the virtual decay 16N -- 15N ＋ n are extracted from the 15N（7Li, 6Li）16N reaction populating the ground and first three excited states in 16N. The root-mean-square （rms） radii of the valence neutron in these four low-lying 16N states are then derived by using the ANCs. The probabilities of the valence neutron staying out of the core potentials are found to be 31%± 8%, 58%± 12%, 3270 ± 8%, and 60% ± 12%. The present results support the conclusion that a one-neutron halo may be formed in the 16N first and third excited states, while the ground and second excited states do not have a one-neutron halo structure. However, the core excitation effect has a strong influence on the one-neutron halo structure of the ground and first excited states in 16N.展开更多
The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li)=44.0 MeV was measured at the HI-13 tandem accelerator of Beijing,China.The asymptotic normalization coefficient(ANC)of 13N→12C+p was derived to be(1....The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li)=44.0 MeV was measured at the HI-13 tandem accelerator of Beijing,China.The asymptotic normalization coefficient(ANC)of 13N→12C+p was derived to be(1.64±0.11)fm-1/2 through the distorted wave Born approximation(DWBA)analysis.The ANC was then used to deduce the astrophysical S(E)factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance.展开更多
Let C be a nonempty bounded subset of a p-uniformly convex Banach space X, and T = {T(t): t S} be a Lipschitzian semigroup on C with lim inf |||T(t)||| < Np, where Np is n→ t s the normal structure coefficient of ...Let C be a nonempty bounded subset of a p-uniformly convex Banach space X, and T = {T(t): t S} be a Lipschitzian semigroup on C with lim inf |||T(t)||| < Np, where Np is n→ t s the normal structure coefficient of X. Suppose also there exists a nonempty bounded closed convex subset E of C with the following properties: (P1)x: E implies ωω(χ) C E; (P2)T is asymptotically regular on E. The authors prove that there exists a z E such that T(s)z = z for all s S. Fruther, under the similar condition, the existence of fixed points of Lipschitzian semigroups in a uniformly convex Banach space is discussed.展开更多
This study focuses on the stability and local bifurcations of a discrete-time SIR epidemic model with logistic growth of the susceptible individuals analytically,and numerically.The analytical results are obtained usi...This study focuses on the stability and local bifurcations of a discrete-time SIR epidemic model with logistic growth of the susceptible individuals analytically,and numerically.The analytical results are obtained using thenormal form technique and numerical results are obtained using the numerical continuation method.For this model,a number of bifurcations are studied,including the transcritical(pitchfork)and fip bifurcations,the Neimark-Sacker(NS)bifurcations,and the strong resonance bifurcations.We especially determine the dynamical behaviors of the model for higher iterations up to fourth-order.Numerical simulation is employed to present a closed invariant curve emerging about an NS point,and its breaking down to several closed invariant curves and eventuality giving rise to a chaotic strange attractor by increasing the bifurcation parameter.展开更多
基金supported by the National Natural Science Foundation of China(Nos.U2167209 and 12175114)the National Key R&D Program of China(No.2021YFF0603600).
文摘The rise in breast cancer diagnoses among Chinese women has necessitated the use of X-ray breast screening,which carries a radiation risk.This study aimed to provide a dosimetry protocol for the Chinese female population to replace the traditional standard that utilizes simplified breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed Chinese female breast models and representative breast parameters was constructed.Considering backscatter radiation and computational efficiency,we improved the combination of these models and the Chinese reference adult female whole-body voxel phantom.Image acquisition for four commercial DBT systems that are widely employed in China was simulated using the Monte Carlo method to obtain the normalized glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray spectra.We calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3,4,5,6,and 7 cm)at various tube potentials(25,28,30,32,35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was investigated.The D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in China.The difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth direction.The results obtained in this study may be used to improve breast dosimetry in China and provide more detailed information on risk assessment during DBT.
文摘The exact classical limits for the coefficient of variation c for the normal distribution are derived. The hand-calculating approximated classical limits for c having high accuracy are given to meet practical engineering needs. Using Odeh and Owen's computational method and Brent's algorithm, the tables for the r-upper exact classical limits of coefficient of variation for normal distribution are calculated for the different confidence coefficient y, the sample size n=1(1)30,40,60,120, the sample coefficient of variation c=0.01(0.01)0.20. It is shown that if n<8,c<0.20, then the V -upper exact classical limits cu for c are slightly higher than the exact fiducial limits cu,F for c if. n>8, c<0.02,then cu-cu,f<5x10-6
基金Supported by the National Natural Science Foundation of China(No.81072841)the Shanghai Science and Technology Research Grant Program(No.09dZ1971600)State Key Clinical Department of TCM pediatrics
文摘OBJECTIVE:To establish a quantification model of Traditional Chinese Medicine(TCM)syndromes by sampling patients undergoing idiopathic precocious puberty(IPP)and early puberty.METHODS:A questionnaire for classifying and quantifying TCM syndromes was designed and administered.All the results were analyzed;the relationship between 3 types of syndrome and 47symptoms were summated.Meanwhile,the frequency distribution of each symptom or sign was aggregated.Fuzzy mathematics was used to develop a quantification model ofTCM syndromes.RESULTS:We found that precocious puberty had 3types of syndrome,including hyperactivity of fire due to Yin deficiency(Syndrome I),depressed liver Qi transforming into fire(Syndrome II),and end retention of damp heat(Syndrome III).In the IPP group,Syndrome I was the most common principal syndrome(100%).Forty-six patients(43.81%)werediagnosed with Syndrome I accompanied by Syndrome II and 11(10.48%)were diagnosed with Syndrome I accompanied by Syndrome III.In the early puberty group,Syndrome I was also the main syndrome(98.39%).The degrees of most symptoms were mild to moderate.Reddened tongue was the most common tongue manifestation(62.86%prevalence)in the IPP group.The most common pulse manifestations were slippery pulse,thread pulse,and taut pulse.The Asymptotic Normalization Coefficient(ANC)method was used to quantify the TCM syndromes in 167 cases.Diagnostic accuracy rate reached 91%,comparable to expert diagnosis.CONCLUSION:We find that there are 3 types of syndrome in the IPP group and in the early puberty group.Syndrome I(hyperactivity of fire due to Yin deficiency)is the main syndrome in the two groups.ANC may be an appropriate for quantification model ofTCM syndromes.
文摘Due to the presence of non-stationarities and discontinuities in the audio signal, segmentation and classification of audio signal is a really challenging task. Automatic music classification and annotation is still considered as a challenging task due to the difficulty of extracting and selecting the optimal audio features. Hence, this paper proposes an efficient approach for segmentation, feature extraction and classification of audio signals. Enhanced Mel Frequency Cepstral Coefficient (EMFCC)-Enhanced Power Normalized Cepstral Coefficients (EPNCC) based feature extraction is applied for the extraction of features from the audio signal. Then, multi-level classification is done to classify the audio signal as a musical or non-musical signal. The proposed approach achieves better performance in terms of precision, Normalized Mutual Information (NMI), F-score and entropy. The PNN classifier shows high False Rejection Rate (FRR), False Acceptance Rate (FAR), Genuine Acceptance rate (GAR), sensitivity, specificity and accuracy with respect to the number of classes.
基金Supported by the National Key Research and Development Program of China(2016YFA0400502)the National Natural Science Foundation of China(11975316,11490561,11535004,11775013)+1 种基金the Continuous Basic Scientific Research Project(WDJC-2019-13)the 973 Program(2013CB834406)。
文摘The radionuclide 22Na generates the emission of a characteristic 1.275 MeVγ-ray.This is a potential astronomical observable,whose occurrence is suspected in classical novae.The 22Mg(p,γ)23Al reaction is relevant to the nucleosynthesis of 22Na in Ne-rich novae.In this study,employing the adiabatic distorted wave approximation and continuum discretized coupled channel methods,the squared neutron asymptotic normalization coefficients(ANCs)231 for the virtual decay of Ne→22Ne+n were extracted,and determined as(0.483±0.060)fm-1 and(9.7±2.3)fm-1 for the ground state and the first excited state from the experimental angular distributions of 22Ne(d,p)23Ne populating the ground state and the first excited state of 23Ne,respectively.Then,the squared proton ANC of 23Alg.s.was obtained as Cd5/22(23Al)(2.65±0.33)×103 fm-1 according to the charge symmetry of the strong interaction.The astrophysical S-factors and reaction rates for the direct capture contribution in 22Mg(p,γ)23Al were also presented.Furthermore,the proton width of the first excited state of 23Al was derived to be(57±14)eV from the neutron ANC of its mirror state in 23Ne and used to compute the contribution from the first resonance of 23Al.This result demonstrates that the direct capture dominates the 22Mg(p,γ)23Al reaction at most temperatures of astrophysical relevance for 0.33<T9<0.64.
基金Supported by National Natural Science Foundation of China(11505117,11490560,11475264,11321064,11375269)Natural Science Foundation of Guangdong Province(2015A030310012)+1 种基金973 program of China(2013CB834406)National key Research and Development Province(2016YFA0400502)
文摘The asymptotic normalization coefficients （ANCs） of the virtual decay 16N -- 15N ＋ n are extracted from the 15N（7Li, 6Li）16N reaction populating the ground and first three excited states in 16N. The root-mean-square （rms） radii of the valence neutron in these four low-lying 16N states are then derived by using the ANCs. The probabilities of the valence neutron staying out of the core potentials are found to be 31%± 8%, 58%± 12%, 3270 ± 8%, and 60% ± 12%. The present results support the conclusion that a one-neutron halo may be formed in the 16N first and third excited states, while the ground and second excited states do not have a one-neutron halo structure. However, the core excitation effect has a strong influence on the one-neutron halo structure of the ground and first excited states in 16N.
基金supported by the National Basic Research Program of China(Grant No.2007CB815003)the National Natural Science Foundation of China(Grant Nos.10675173,10605039,10705053,10735100,10720101076,10875175 and 10975193)
文摘The angular distribution of the 12C(7Li,6He)13N reaction at E(7Li)=44.0 MeV was measured at the HI-13 tandem accelerator of Beijing,China.The asymptotic normalization coefficient(ANC)of 13N→12C+p was derived to be(1.64±0.11)fm-1/2 through the distorted wave Born approximation(DWBA)analysis.The ANC was then used to deduce the astrophysical S(E)factors and reaction rates for the 12C(p,γ)13N direct capture reaction at energies of astrophysical relevance.
基金the National Natural Science Foundation of China (No.19801023) and theTeaching and Research Award Fund for Outstanding Young T
文摘Let C be a nonempty bounded subset of a p-uniformly convex Banach space X, and T = {T(t): t S} be a Lipschitzian semigroup on C with lim inf |||T(t)||| < Np, where Np is n→ t s the normal structure coefficient of X. Suppose also there exists a nonempty bounded closed convex subset E of C with the following properties: (P1)x: E implies ωω(χ) C E; (P2)T is asymptotically regular on E. The authors prove that there exists a z E such that T(s)z = z for all s S. Fruther, under the similar condition, the existence of fixed points of Lipschitzian semigroups in a uniformly convex Banach space is discussed.
文摘This study focuses on the stability and local bifurcations of a discrete-time SIR epidemic model with logistic growth of the susceptible individuals analytically,and numerically.The analytical results are obtained using thenormal form technique and numerical results are obtained using the numerical continuation method.For this model,a number of bifurcations are studied,including the transcritical(pitchfork)and fip bifurcations,the Neimark-Sacker(NS)bifurcations,and the strong resonance bifurcations.We especially determine the dynamical behaviors of the model for higher iterations up to fourth-order.Numerical simulation is employed to present a closed invariant curve emerging about an NS point,and its breaking down to several closed invariant curves and eventuality giving rise to a chaotic strange attractor by increasing the bifurcation parameter.
