In the present paper two contents are enclosed .First ,the Fourier analysis approach of the dispersion relation and group velocity effect of finite difference schemes is discussed.the defects of the approach is pointe...In the present paper two contents are enclosed .First ,the Fourier analysis approach of the dispersion relation and group velocity effect of finite difference schemes is discussed.the defects of the approach is pointed out and the correction is made;Second,a new systematic analysis method -remaider -effect analysis (abbr.REAM)is proposed by means of the modified partial differential equations (abbr MPDE)of finite difference schemes.The analysis is based on the synthetical study of the rational dispersion-and dissipation relations of finite difference schemes.And the method clearly possesses constructivity展开更多
BACKGROUND Depression and anxiety are prevalent psychological challenges among patients with adolescent idiopathic scoliosis(AIS),affecting individuals across both sex and age groups.AIM To explore the network structu...BACKGROUND Depression and anxiety are prevalent psychological challenges among patients with adolescent idiopathic scoliosis(AIS),affecting individuals across both sex and age groups.AIM To explore the network structure of depression and anxiety symptoms,with a focus on identifying differences at the symptom level between sex and age subgroups.METHODS A total of 1955 participants diagnosed with AIS aged 10-18 years were assessed using the Patient Health Questionnaire Depression Scale(PHO-9)and the Generalized Anxiety Disorder Scale(GAD-7),and 765 patients exhibiting PHQ-9 or GAD-7 scores ≥ 5 were enrolled in our study. Network analysis and network comparison tests were utilized toconstruct and compare the depression-anxiety symptoms networks among sex and age subgroups.RESULTSThe results revealed GAD3 “Excessive worry” and PHQ2 “Sad mood” were the most significant central symptomsin all subgroups, while “Sad mood” had higher strength than “Excessive worry” in the lower age group. In thenetwork comparisons, the female network exhibited tighter connectivity, especially on GAD6 “Irritability” andGAD2 “Uncontrollable worry”, while only PHQ3 “Sleep” and PHQ9 “Suicidal ideation” had differences at thelocal level in the lower age group.CONCLUSIONSeveral interventions targeting excessive worry and sad mood could reduce the risk of depression and anxietysymptoms in the AIS population. Furthermore, specific anxiety symptoms in females, along with sleep disturbancesand suicidal ideation in the lower age group, should be addressed at an early stage to prevent significantdisruptions in mental health trajectories.展开更多
Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is...Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.展开更多
By extending the concept of diffusion to the potential energy landscapes(PELs), we introduce the meansquared energy difference(MSED) as a novel quantity to investigate the intrinsic properties of supercooled liquids. ...By extending the concept of diffusion to the potential energy landscapes(PELs), we introduce the meansquared energy difference(MSED) as a novel quantity to investigate the intrinsic properties of supercooled liquids. MSED can provide a clear description of the “energy relaxation” process on a PEL. Through MSED analysis, we have obtained a characteristic time similar to that derived from structure analysis, namely τ_(α)^(*).Further, we establish a connection between MSED and the feature of PELs, providing a concise and quantitative description of PELs. The relaxation behavior of energy has been found to follow a stretched exponential form.As the temperature decreases, the roughness of the accessible PEL changes significantly around a characteristic temperature T_(x), which is 20% higher than the glass transition temperature T_(g) and is comparable to the critical temperature of the mode-coupling theory. More importantly, one of the PEL parameters is closely related to the Adam–Gibbs configurational entropy. The present research, which directly links the PEL to the relaxation process, provides avenues for further research of glasses.展开更多
The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(...The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(2)=p(z)or[p1(z)f′(z)]^(2)+[p2(z)f(z+c)+p3(z)f(z)]^(2)=p(z);where c is a nonzero complex number,p1;p2 and p3 are polynomials in C satisfying p1p3■0;and p is a nonzero irreducible polynomial in C.展开更多
Change detection(CD)plays a crucial role in numerous fields,where both convolutional neural networks(CNNs)and Transformers have demonstrated exceptional performance in CD tasks.However,CNNs suffer from limited recepti...Change detection(CD)plays a crucial role in numerous fields,where both convolutional neural networks(CNNs)and Transformers have demonstrated exceptional performance in CD tasks.However,CNNs suffer from limited receptive fields,hindering their ability to capture global features,while Transformers are constrained by high computational complexity.Recently,Mamba architecture,which is based on state space models(SSMs),has shown powerful global modeling capabilities while achieving linear computational complexity.Although some researchers have incorporated Mamba into CD tasks,the existing Mamba⁃based remote sensing CD methods struggle to effectively perceive the inherent locality of changed regions when flattening and scanning remote sensing images,leading to limitations in extracting change features.To address these issues,we propose a novel Mamba⁃based CD method termed difference feature fusion Mamba model(DFFMamba)by mitigating the loss of feature locality caused by traditional Mamba⁃style scanning.Specifically,two distinct difference feature extraction modules are designed:Difference Mamba(DMamba)and local difference Mamba(LDMamba),where DMamba extracts difference features by calculating the difference in coefficient matrices between the state⁃space equations of the bi⁃temporal features.Building upon DMamba,LDMamba combines a locally adaptive state⁃space scanning(LASS)strategy to enhance feature locality so as to accurately extract difference features.Additionally,a fusion Mamba(FMamba)module is proposed,which employs a spatial⁃channel token modeling SSM(SCTMS)unit to integrate multi⁃dimensional spatio⁃temporal interactions of change features,thereby capturing their dependencies across both spatial and channel dimensions.To verify the effectiveness of the proposed DFFMamba,extensive experiments are conducted on three datasets of WHU⁃CD,LEVIR⁃CD,and CLCD.The results demonstrate that DFFMamba significantly outperforms state⁃of⁃the⁃art CD methods,achieving intersection over union(IoU)scores of 90.67%,85.04%,and 66.56%on the three datasets,respectively.展开更多
The explicit compact difference scheme, proposed in Three-point explicit compact difference scheme with arbitrary order of accuracy and its application in CFD by Lin et al., published in Applied Mathematics and Mechan...The explicit compact difference scheme, proposed in Three-point explicit compact difference scheme with arbitrary order of accuracy and its application in CFD by Lin et al., published in Applied Mathematics and Mechanics (English Edition), 2007, 28(7), 943-953, has the same performance as the conventional finite difference schemes. It is just another expression of the conventional finite difference schemes. The proposed expression does not have the advantages of a compact difference scheme. Nonetheless, we can more easily obtain and implement compared with the conventional expression in which the coefficients can only be obtained by solving equations, especially for higher accurate schemes.展开更多
Background: For nursing students, gathering social information is essential for understanding healthcare and social issues and developing critical thinking and decision-making skills. However, the choice of informatio...Background: For nursing students, gathering social information is essential for understanding healthcare and social issues and developing critical thinking and decision-making skills. However, the choice of information sources varies by age and individual habits. With the widespread use of the internet, there are notable differences between younger and older generations in their reliance on the internet versus traditional media sources like newspapers and television. Given the wide age range and diverse backgrounds of nursing students, understanding generational differences in information-gathering methods is important for implementing effective education. Purpose: The purpose of this study is to identify how nursing students in different age groups obtain social information and to examine media usage trends by age group. Additionally, we aim to use the findings to provide insights into effective information dissemination methods in nursing education. Results: The results showed that nursing students in their teens to forties, regardless of gender, primarily relied on the internet as their main information source, with television playing a secondary role. In contrast, students in their fifties tended to obtain information more often from newspapers and television than from the internet. This highlights an age-related difference in preferred information sources, with older students showing a greater reliance on traditional media. Conclusions: This study demonstrates that nursing students use different information-gathering methods based on their age, suggesting a need to custo-mize information dissemination strategies in nursing education. Digital media may be more effective for younger students, while traditional media or printed materials might better serve older students. Educational institutions should consider these generational differences in media usage and adopt strategies that meet the diverse needs of their student populations.展开更多
The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the p...The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the patient's perspective.This comprehensive review analyzes the evolution,applications,and challenges of MCID across medical specialties,emphasizing its necessity in ensuring that clinical outcomes not only demonstrate statistical significance but also offer genuine clinical utility that aligns with patient expectations and needs.We discuss the evolution of MCID since its inception in the 1980s,its current applications across various medical specialties,and the methodologies used in its calculation,highlighting both anchor-based and distribution-based approaches.Furthermore,the paper delves into the challenges associated with the application of MCID,such as methodological variability and the interpretation difficulties that arise in clinical settings.Recommendations for the future include standardizing MCID calculation methods,enhancing patient involvement in setting MCID thresholds,and extending research to incorporate diverse global perspectives.These steps are critical to refining the role of MCID in patient-centered healthcare,addressing existing gaps in methodology and interpretation,and ensuring that medical interventions lead to significant,patient-perceived improvements.展开更多
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a...To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.展开更多
Objective:Near vision loss(NVL)is one of the leading causes of visual impairment worldwide,exerting a profound impact on individual quality of life and socio-economic development.This study aims to analyze the burden ...Objective:Near vision loss(NVL)is one of the leading causes of visual impairment worldwide,exerting a profound impact on individual quality of life and socio-economic development.This study aims to analyze the burden of NVL in China by sex and age groups from 1990 to 2021 and to project trends over the next 15 years.Methods:Using data from the Global Burden of Disease(GBD)2021 database,we conducted descriptive analyses of NVL prevalence in China,calculated age-standardized prevalence rates(ASPR)and age-standardized disability-adjusted life years rates(ASDR)to compare burden differences between sexes and age groups,and applied an autoregressive integrated moving average(ARIMA)model to predict NVL trends for the next 15 years.The model selection was based on best-fit criteria to ensure reliable projections.Results:From 1990 to 2021,China’s ASPR of NVL rose from 10096.24/100000 to 15624.54/100000,and ASDR increased from 101.75/100000 to 158.75/100000.In 2021,ASPR(16551.70/100000)and ASDR(167.69/100000)were higher among females than males(14686.21/100000 and 149.76/100000,respectively).China ranked highest globally in both NVL cases and disability-adjusted life years(DALYs),with female burden significantly exceeding male burden.Projections indicated this trend and sex gap will persist until 2036.Compared with 1990,the prevalence cases and DALYs increased by 239.20%and 238.82%,respectively in 2021,with the highest burden among females and the 55−59 age group.The ARIMA model predicted continued increases in prevalence and DALYs by 2036,with females maintaining a higher burden than males.Conclusion:This study reveals a marked increase in the NVL burden in China and predicts continued growth in the coming years.Public health policies should prioritize NVL prevention and control,with special attention to women and middle-aged populations to mitigate long-term societal and health impacts.展开更多
The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time...The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time difference of repetitively PQS four-level and quasi-three-level lasers have been developed respectively.Then,according to the temporal criterion,the required conditions for repetitively PQS four-level and quasi-three-level lasers to achieve SLM operation are analyzed.The analysis results show that in addition to the short cavity is conducive to obtaining the pulsed SLM laser,the use of a lower pump power(compared to the threshold power)will help to obtain a longer pulse buildup-time difference and thus enabling the SLM operation.Moreover,it is worth noting that for the quasi-three-level lasers,the pulse buildup-time difference also depends on the initial population inversion density.The results also reveal that setting resonator parameters that can obtain large initial population inversion density will be helpful to the SLM operation in both four-level and quasithree-level regimes.In addition,the use of saturable absorber with a low absorption cross-section ratio between the excited state and ground state also contributes to the realization of the SLM.Finally,the optimization model of passively Q-switched single-longitudinal-mode laser is established.In addition to predicting the output performance of the laser,this model can also be used to obtain the optimal resonator parameters and the upper limit of pump power for SLM operation.展开更多
To enhance the computational efficiency of spatio-temporally discretized phase-field models,we present a high-speed solver specifically designed for the Poisson equations,a component frequently used in the numerical c...To enhance the computational efficiency of spatio-temporally discretized phase-field models,we present a high-speed solver specifically designed for the Poisson equations,a component frequently used in the numerical computation of such models.This efficient solver employs algorithms based on discrete cosine transformations(DCT)or discrete sine transformations(DST)and is not restricted by any spatio-temporal schemes.Our proposed methodology is appropriate for a variety of phase-field models and is especially efficient when combined with flow field systems.Meanwhile,this study has conducted an extensive numerical comparison and found that employing DCT and DST techniques not only yields results comparable to those obtained via the Multigrid(MG)method,a conventional approach used in the resolution of the Poisson equations,but also enhances computational efficiency by over 90%.展开更多
A method combining finite difference method(FDM)and k-means clustering algorithm which can determine the threshold of rock bridge generation is proposed.Jointed slope models with different joint coalescence coefficien...A method combining finite difference method(FDM)and k-means clustering algorithm which can determine the threshold of rock bridge generation is proposed.Jointed slope models with different joint coalescence coefficients(k)are constructed based on FDM.The rock bridge area was divided through k-means algorithm and the optimal number of clusters was determined by sum of squared errors(SSE)and elbow method.The influence of maximum principal stress and stress change rate as clustering indexes on the clustering results of rock bridges was compared by using Euclidean distance.The results show that using stress change rate as clustering index is more effective.When the joint coalescence coefficient is less than 0.6,there is no significant stress concentration in the middle area of adjacent joints,that is,no generation of rock bridge.In addition,the range of rock bridge is affected by the coalescence coefficient(k),the relative position of joints and the parameters of weak interlayer.展开更多
Population migration data derived from location-based services has often been used to delineate population flows between cities or construct intercity relationship networks to reveal and explore the complex interactio...Population migration data derived from location-based services has often been used to delineate population flows between cities or construct intercity relationship networks to reveal and explore the complex interaction patterns underlying human activities.Nevertheless,the inherent heterogeneity in multimodal migration big data has been ignored.This study conducts an in-depth comparison and quantitative analysis through a comprehensive lens of spatial association.Initially,the intercity interactive networks in China were constructed,utilizing migration data from Baidu and AutoNavi collected during the same time period.Subsequently,the characteristics and spatial structure similarities of the two types of intercity interactive networks were quantitatively assessed and analyzed from overall(network)and local(node)perspectives.Furthermore,the precision of these networks at the local scale is corroborated by constructing an intercity network from mobile phone(MP)data.Results indicate that the intercity interactive networks in China,as delineated by Baidu and AutoNavi migration flows,exhibit a high degree of structure equivalence.The correlation coefficient between these two networks is 0.874.Both networks exhibit a pronounced spatial polarization trend and hierarchical structure.This is evident in their distinct core and peripheral structures,as well as in the varying importance and influence of different nodes within the networks.Nevertheless,there are notable differences worthy of attention.Baidu intercity interactive network exhibits pronounced cross-regional effects,and its high-level interactions are characterized by a“rich-club”phenomenon.The AutoNavi intercity interactive network presents a more significant distance attenuation effect,and the high-level interactions display a gradient distribution pattern.Notably,there exists a substantial correlation between the AutoNavi and MP networks at the local scale,evidenced by a high correlation coefficient of 0.954.Furthermore,the“spatial dislocations”phenomenon was observed within the spatial structures at different levels,extracted from the Baidu and AutoNavi intercity networks.However,the measured results of network spatial structure similarity from three dimensions,namely,node location,node size,and local structure,indicate a relatively high similarity and consistency between the two networks.展开更多
This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace...This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.展开更多
To understand career adaptability among undergraduates majoring in Primary Education in provincial normal universities,this study surveyed 257 such students and analyzed the current state and characteristics of their ...To understand career adaptability among undergraduates majoring in Primary Education in provincial normal universities,this study surveyed 257 such students and analyzed the current state and characteristics of their career adaptability.The results indicate that their overall career adaptability is moderately high.Significant differences in career adaptability were found by program type.Maternal education exerted a notable influence on overall career adaptability and on the“career confidence”dimension,whereas paternal education only showed a highly significant effect on“career confidence.”Therefore,schools should consolidate their role as the main arena for education,while families should provide supportive environments,jointly addressing the career adaptation and development needs of Primary Education undergraduates and further enhancing their career adaptability.展开更多
文摘In the present paper two contents are enclosed .First ,the Fourier analysis approach of the dispersion relation and group velocity effect of finite difference schemes is discussed.the defects of the approach is pointed out and the correction is made;Second,a new systematic analysis method -remaider -effect analysis (abbr.REAM)is proposed by means of the modified partial differential equations (abbr MPDE)of finite difference schemes.The analysis is based on the synthetical study of the rational dispersion-and dissipation relations of finite difference schemes.And the method clearly possesses constructivity
基金Supported by The Sanming Project of Medicine in Shenzhen,No.SZSM202211003Shenzhen-Hong Kong Jointly Funded Project,Shenzhen Science and Technology Program,No.SGDX20230116093645007+1 种基金Shenzhen Second People's Hospital Clinical Project,No.20243357003Shenzhen Medical Research Fund,No.B2303005.
文摘BACKGROUND Depression and anxiety are prevalent psychological challenges among patients with adolescent idiopathic scoliosis(AIS),affecting individuals across both sex and age groups.AIM To explore the network structure of depression and anxiety symptoms,with a focus on identifying differences at the symptom level between sex and age subgroups.METHODS A total of 1955 participants diagnosed with AIS aged 10-18 years were assessed using the Patient Health Questionnaire Depression Scale(PHO-9)and the Generalized Anxiety Disorder Scale(GAD-7),and 765 patients exhibiting PHQ-9 or GAD-7 scores ≥ 5 were enrolled in our study. Network analysis and network comparison tests were utilized toconstruct and compare the depression-anxiety symptoms networks among sex and age subgroups.RESULTSThe results revealed GAD3 “Excessive worry” and PHQ2 “Sad mood” were the most significant central symptomsin all subgroups, while “Sad mood” had higher strength than “Excessive worry” in the lower age group. In thenetwork comparisons, the female network exhibited tighter connectivity, especially on GAD6 “Irritability” andGAD2 “Uncontrollable worry”, while only PHQ3 “Sleep” and PHQ9 “Suicidal ideation” had differences at thelocal level in the lower age group.CONCLUSIONSeveral interventions targeting excessive worry and sad mood could reduce the risk of depression and anxietysymptoms in the AIS population. Furthermore, specific anxiety symptoms in females, along with sleep disturbancesand suicidal ideation in the lower age group, should be addressed at an early stage to prevent significantdisruptions in mental health trajectories.
基金National Key R&D Program of China,Grant/Award Number:2021YFF0703200Key Technology Fund of the National Institutes for Food and Drug Control,Grant/Award Number:GJJS-2022-1-5。
文摘Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.
基金supported by the National Key Research and Development Program of China (Grant No. 2022YFA1404603)by the National Natural Science Foundation of China (Grant Nos. 12274127 and 12188101)。
文摘By extending the concept of diffusion to the potential energy landscapes(PELs), we introduce the meansquared energy difference(MSED) as a novel quantity to investigate the intrinsic properties of supercooled liquids. MSED can provide a clear description of the “energy relaxation” process on a PEL. Through MSED analysis, we have obtained a characteristic time similar to that derived from structure analysis, namely τ_(α)^(*).Further, we establish a connection between MSED and the feature of PELs, providing a concise and quantitative description of PELs. The relaxation behavior of energy has been found to follow a stretched exponential form.As the temperature decreases, the roughness of the accessible PEL changes significantly around a characteristic temperature T_(x), which is 20% higher than the glass transition temperature T_(g) and is comparable to the critical temperature of the mode-coupling theory. More importantly, one of the PEL parameters is closely related to the Adam–Gibbs configurational entropy. The present research, which directly links the PEL to the relaxation process, provides avenues for further research of glasses.
基金Supported by the National Natural Science Foundation of China(11871260,11761050)the Jiangxi Natural Science Foundation(#20232ACB201005)+1 种基金the Shandong Natural Science Foundation(#ZR2024MA024)Doctoral Startup Fund of Jiangxi Science and Technology Normal University(#2021BSQD30).
文摘The main purpose of this paper is to try to find all entire solutions of the Fermat type difference-differential equation[p1(z)f(z+c)]^(2)+[p2(z)f(z)+p3(z)f′(z)]^(2)=p(z);or[p1(z)f(z)]^(2)+[p2(z)f′(z)+p3(z)f(z+c)]^(2)=p(z)or[p1(z)f′(z)]^(2)+[p2(z)f(z+c)+p3(z)f(z)]^(2)=p(z);where c is a nonzero complex number,p1;p2 and p3 are polynomials in C satisfying p1p3■0;and p is a nonzero irreducible polynomial in C.
基金supported by the National Natural Science Foundation of China(Nos.42371449,41801386).
文摘Change detection(CD)plays a crucial role in numerous fields,where both convolutional neural networks(CNNs)and Transformers have demonstrated exceptional performance in CD tasks.However,CNNs suffer from limited receptive fields,hindering their ability to capture global features,while Transformers are constrained by high computational complexity.Recently,Mamba architecture,which is based on state space models(SSMs),has shown powerful global modeling capabilities while achieving linear computational complexity.Although some researchers have incorporated Mamba into CD tasks,the existing Mamba⁃based remote sensing CD methods struggle to effectively perceive the inherent locality of changed regions when flattening and scanning remote sensing images,leading to limitations in extracting change features.To address these issues,we propose a novel Mamba⁃based CD method termed difference feature fusion Mamba model(DFFMamba)by mitigating the loss of feature locality caused by traditional Mamba⁃style scanning.Specifically,two distinct difference feature extraction modules are designed:Difference Mamba(DMamba)and local difference Mamba(LDMamba),where DMamba extracts difference features by calculating the difference in coefficient matrices between the state⁃space equations of the bi⁃temporal features.Building upon DMamba,LDMamba combines a locally adaptive state⁃space scanning(LASS)strategy to enhance feature locality so as to accurately extract difference features.Additionally,a fusion Mamba(FMamba)module is proposed,which employs a spatial⁃channel token modeling SSM(SCTMS)unit to integrate multi⁃dimensional spatio⁃temporal interactions of change features,thereby capturing their dependencies across both spatial and channel dimensions.To verify the effectiveness of the proposed DFFMamba,extensive experiments are conducted on three datasets of WHU⁃CD,LEVIR⁃CD,and CLCD.The results demonstrate that DFFMamba significantly outperforms state⁃of⁃the⁃art CD methods,achieving intersection over union(IoU)scores of 90.67%,85.04%,and 66.56%on the three datasets,respectively.
基金Supported by the National Natural Science Foundation of China (Nos.50876114 and 10602043)the Program for New Century Excellent Talents in University,and the Scientific Research Key Project Fund of Ministry of Education (No.106142)
文摘The explicit compact difference scheme, proposed in Three-point explicit compact difference scheme with arbitrary order of accuracy and its application in CFD by Lin et al., published in Applied Mathematics and Mechanics (English Edition), 2007, 28(7), 943-953, has the same performance as the conventional finite difference schemes. It is just another expression of the conventional finite difference schemes. The proposed expression does not have the advantages of a compact difference scheme. Nonetheless, we can more easily obtain and implement compared with the conventional expression in which the coefficients can only be obtained by solving equations, especially for higher accurate schemes.
文摘Background: For nursing students, gathering social information is essential for understanding healthcare and social issues and developing critical thinking and decision-making skills. However, the choice of information sources varies by age and individual habits. With the widespread use of the internet, there are notable differences between younger and older generations in their reliance on the internet versus traditional media sources like newspapers and television. Given the wide age range and diverse backgrounds of nursing students, understanding generational differences in information-gathering methods is important for implementing effective education. Purpose: The purpose of this study is to identify how nursing students in different age groups obtain social information and to examine media usage trends by age group. Additionally, we aim to use the findings to provide insights into effective information dissemination methods in nursing education. Results: The results showed that nursing students in their teens to forties, regardless of gender, primarily relied on the internet as their main information source, with television playing a secondary role. In contrast, students in their fifties tended to obtain information more often from newspapers and television than from the internet. This highlights an age-related difference in preferred information sources, with older students showing a greater reliance on traditional media. Conclusions: This study demonstrates that nursing students use different information-gathering methods based on their age, suggesting a need to custo-mize information dissemination strategies in nursing education. Digital media may be more effective for younger students, while traditional media or printed materials might better serve older students. Educational institutions should consider these generational differences in media usage and adopt strategies that meet the diverse needs of their student populations.
文摘The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the patient's perspective.This comprehensive review analyzes the evolution,applications,and challenges of MCID across medical specialties,emphasizing its necessity in ensuring that clinical outcomes not only demonstrate statistical significance but also offer genuine clinical utility that aligns with patient expectations and needs.We discuss the evolution of MCID since its inception in the 1980s,its current applications across various medical specialties,and the methodologies used in its calculation,highlighting both anchor-based and distribution-based approaches.Furthermore,the paper delves into the challenges associated with the application of MCID,such as methodological variability and the interpretation difficulties that arise in clinical settings.Recommendations for the future include standardizing MCID calculation methods,enhancing patient involvement in setting MCID thresholds,and extending research to incorporate diverse global perspectives.These steps are critical to refining the role of MCID in patient-centered healthcare,addressing existing gaps in methodology and interpretation,and ensuring that medical interventions lead to significant,patient-perceived improvements.
文摘To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.
基金supported by the Natural Science Foundation of Hunan Province(2023JJ30817)Hunan Provincial Natural Science Foundation-Hengyang City Joint Fund Project(2025JJ70129)+1 种基金Changsha Natural Science Foundation(kq2403057)China。
文摘Objective:Near vision loss(NVL)is one of the leading causes of visual impairment worldwide,exerting a profound impact on individual quality of life and socio-economic development.This study aims to analyze the burden of NVL in China by sex and age groups from 1990 to 2021 and to project trends over the next 15 years.Methods:Using data from the Global Burden of Disease(GBD)2021 database,we conducted descriptive analyses of NVL prevalence in China,calculated age-standardized prevalence rates(ASPR)and age-standardized disability-adjusted life years rates(ASDR)to compare burden differences between sexes and age groups,and applied an autoregressive integrated moving average(ARIMA)model to predict NVL trends for the next 15 years.The model selection was based on best-fit criteria to ensure reliable projections.Results:From 1990 to 2021,China’s ASPR of NVL rose from 10096.24/100000 to 15624.54/100000,and ASDR increased from 101.75/100000 to 158.75/100000.In 2021,ASPR(16551.70/100000)and ASDR(167.69/100000)were higher among females than males(14686.21/100000 and 149.76/100000,respectively).China ranked highest globally in both NVL cases and disability-adjusted life years(DALYs),with female burden significantly exceeding male burden.Projections indicated this trend and sex gap will persist until 2036.Compared with 1990,the prevalence cases and DALYs increased by 239.20%and 238.82%,respectively in 2021,with the highest burden among females and the 55−59 age group.The ARIMA model predicted continued increases in prevalence and DALYs by 2036,with females maintaining a higher burden than males.Conclusion:This study reveals a marked increase in the NVL burden in China and predicts continued growth in the coming years.Public health policies should prioritize NVL prevention and control,with special attention to women and middle-aged populations to mitigate long-term societal and health impacts.
基金Project supported by National Natural Science Foundation of China(Grant No.62205102)。
文摘The pulsed single-longitudinal-mode(SLM)operation caused by the modal-gain difference in a repetitively passively Q-switched(PQS)laser is studied in detail.Firstly,the analytical expressions for the pulse buildup-time difference of repetitively PQS four-level and quasi-three-level lasers have been developed respectively.Then,according to the temporal criterion,the required conditions for repetitively PQS four-level and quasi-three-level lasers to achieve SLM operation are analyzed.The analysis results show that in addition to the short cavity is conducive to obtaining the pulsed SLM laser,the use of a lower pump power(compared to the threshold power)will help to obtain a longer pulse buildup-time difference and thus enabling the SLM operation.Moreover,it is worth noting that for the quasi-three-level lasers,the pulse buildup-time difference also depends on the initial population inversion density.The results also reveal that setting resonator parameters that can obtain large initial population inversion density will be helpful to the SLM operation in both four-level and quasithree-level regimes.In addition,the use of saturable absorber with a low absorption cross-section ratio between the excited state and ground state also contributes to the realization of the SLM.Finally,the optimization model of passively Q-switched single-longitudinal-mode laser is established.In addition to predicting the output performance of the laser,this model can also be used to obtain the optimal resonator parameters and the upper limit of pump power for SLM operation.
基金Supported by Shanxi Province Natural Science Research(202203021212249)Special/Youth Foundation of Taiyuan University of Technology(2022QN101)+3 种基金National Natural Science Foundation of China(12301556)Research Project Supported by Shanxi Scholarship Council of China(2021-029)International Cooperation Base and Platform Project of Shanxi Province(202104041101019)Basic Research Plan of Shanxi Province(202203021211129)。
文摘To enhance the computational efficiency of spatio-temporally discretized phase-field models,we present a high-speed solver specifically designed for the Poisson equations,a component frequently used in the numerical computation of such models.This efficient solver employs algorithms based on discrete cosine transformations(DCT)or discrete sine transformations(DST)and is not restricted by any spatio-temporal schemes.Our proposed methodology is appropriate for a variety of phase-field models and is especially efficient when combined with flow field systems.Meanwhile,this study has conducted an extensive numerical comparison and found that employing DCT and DST techniques not only yields results comparable to those obtained via the Multigrid(MG)method,a conventional approach used in the resolution of the Poisson equations,but also enhances computational efficiency by over 90%.
基金supported by the National Natural Science Foundation of China(No.42277175)Guangxi Emergency Management Department 2024 Innovation and Technology Research Project,China(No.2024GXYJ006)+2 种基金Hunan Provincial Department of Natural Resources Geological Exploration Project,China(No.2023ZRBSHZ056)The First National Natural Disaster Comprehensive Risk Survey in Hunan Province,China(No.2022-70)Guizhou Provincial Major Scientific and Technological Program,China(No.2023-425).
文摘A method combining finite difference method(FDM)and k-means clustering algorithm which can determine the threshold of rock bridge generation is proposed.Jointed slope models with different joint coalescence coefficients(k)are constructed based on FDM.The rock bridge area was divided through k-means algorithm and the optimal number of clusters was determined by sum of squared errors(SSE)and elbow method.The influence of maximum principal stress and stress change rate as clustering indexes on the clustering results of rock bridges was compared by using Euclidean distance.The results show that using stress change rate as clustering index is more effective.When the joint coalescence coefficient is less than 0.6,there is no significant stress concentration in the middle area of adjacent joints,that is,no generation of rock bridge.In addition,the range of rock bridge is affected by the coalescence coefficient(k),the relative position of joints and the parameters of weak interlayer.
基金National Natural Science Foundation of China,No.42361040。
文摘Population migration data derived from location-based services has often been used to delineate population flows between cities or construct intercity relationship networks to reveal and explore the complex interaction patterns underlying human activities.Nevertheless,the inherent heterogeneity in multimodal migration big data has been ignored.This study conducts an in-depth comparison and quantitative analysis through a comprehensive lens of spatial association.Initially,the intercity interactive networks in China were constructed,utilizing migration data from Baidu and AutoNavi collected during the same time period.Subsequently,the characteristics and spatial structure similarities of the two types of intercity interactive networks were quantitatively assessed and analyzed from overall(network)and local(node)perspectives.Furthermore,the precision of these networks at the local scale is corroborated by constructing an intercity network from mobile phone(MP)data.Results indicate that the intercity interactive networks in China,as delineated by Baidu and AutoNavi migration flows,exhibit a high degree of structure equivalence.The correlation coefficient between these two networks is 0.874.Both networks exhibit a pronounced spatial polarization trend and hierarchical structure.This is evident in their distinct core and peripheral structures,as well as in the varying importance and influence of different nodes within the networks.Nevertheless,there are notable differences worthy of attention.Baidu intercity interactive network exhibits pronounced cross-regional effects,and its high-level interactions are characterized by a“rich-club”phenomenon.The AutoNavi intercity interactive network presents a more significant distance attenuation effect,and the high-level interactions display a gradient distribution pattern.Notably,there exists a substantial correlation between the AutoNavi and MP networks at the local scale,evidenced by a high correlation coefficient of 0.954.Furthermore,the“spatial dislocations”phenomenon was observed within the spatial structures at different levels,extracted from the Baidu and AutoNavi intercity networks.However,the measured results of network spatial structure similarity from three dimensions,namely,node location,node size,and local structure,indicate a relatively high similarity and consistency between the two networks.
基金Key Program of National Natural Science Foundation of China,No.41930757National Natural Science Foundation of China,No.42371285。
文摘This study explores the impact of intergenerational differences on farmers' terrace abandonment in response to increasing intergenerational differentiation among rural households and the practical issue of terrace abandonment. Logit and Tobit models are employed to conduct empirical analysis and it is found that terrace abandonment increases sequentially among the new, middle, and old generations, confirming that intergenerational differences significantly influence whether farmers abandon terraces and the terrace abandonment scale. Village characteristics and government subsidies significantly influence farmers' terrace abandonment. An increase in the number of migrant workers in the village increases terrace abandonment among new and middle generation farmers, whereas an increase in the distance from the village to the county significantly increases terrace abandonment among old generation farmers. An increase in the village's total population significantly reduces terrace abandonment among new generation farmers. An increase in government subsidies significantly reduces terrace abandonment among middle and old generation farmers. The impact of intergenerational differences on terrace abandonment is more pronounced in low-altitude areas. To reduce terrace abandonment, it is necessary to promote terrace transfer, develop characteristic agriculture, improve terrace farming subsidies, and propose targeted strategies for the different generations of farmers.
基金supported by the School-Level Teaching Reform Research Project of Qilu Normal University(JG202304Z)the Research Project and Platform Cultivation Project for Education and Teaching Reform of Qilu Normal University(BP202416).
文摘To understand career adaptability among undergraduates majoring in Primary Education in provincial normal universities,this study surveyed 257 such students and analyzed the current state and characteristics of their career adaptability.The results indicate that their overall career adaptability is moderately high.Significant differences in career adaptability were found by program type.Maternal education exerted a notable influence on overall career adaptability and on the“career confidence”dimension,whereas paternal education only showed a highly significant effect on“career confidence.”Therefore,schools should consolidate their role as the main arena for education,while families should provide supportive environments,jointly addressing the career adaptation and development needs of Primary Education undergraduates and further enhancing their career adaptability.