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SOME RESULTS REGARDING PARTIAL DIFFERENTIAL POLYNOMIALS AND THE UNIQUENESS OF MEROMORPHIC FUNCTIONS IN SEVERAL VARIABLES
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作者 刘曼莉 高凌云 房少梅 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期821-838,共18页
In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing sm... In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing small functions.As an application of the value distribution result,we study the defect relation of a nonconstant solution to the partial differential equation.In particular,we give a connection between the Picard type theorem of Milliox-Hayman and the characterization of entire solutions of a partial differential equation. 展开更多
关键词 meromorphic function in several variables Nevanlinna theory partial differ-ential equation total derivative
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FRACTIONAL INTEGRALS OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES
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作者 Wang Shiming 《Analysis in Theory and Applications》 1993年第1期82-96,共15页
In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the... In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^2-norm.Results obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n. 展开更多
关键词 TH FRACTIONAL INTEGRALS of PERIODIC functionS of several variables
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Variable stiffness design optimization of fiber-reinforced composite laminates with regular and irregular holes considering fiber continuity for additive manufacturing 被引量:1
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作者 Yi LIU Zunyi DUAN +6 位作者 Chunping ZHOU Yuan SI Chenxi GUAN Yi XIONG Bin XU Jun YAN Jihong ZHU 《Chinese Journal of Aeronautics》 2025年第3期334-354,共21页
Fiber-reinforced composites are an ideal material for the lightweight design of aerospace structures. Especially in recent years, with the rapid development of composite additive manufacturing technology, the design o... Fiber-reinforced composites are an ideal material for the lightweight design of aerospace structures. Especially in recent years, with the rapid development of composite additive manufacturing technology, the design optimization of variable stiffness of fiber-reinforced composite laminates has attracted widespread attention from scholars and industry. In these aerospace composite structures, numerous cutout panels and shells serve as access points for maintaining electrical, fuel, and hydraulic systems. The traditional fiber-reinforced composite laminate subtractive drilling manufacturing inevitably faces the problems of interlayer delamination, fiber fracture, and burr of the laminate. Continuous fiber additive manufacturing technology offers the potential for integrated design optimization and manufacturing with high structural performance. Considering the integration of design and manufacturability in continuous fiber additive manufacturing, the paper proposes linear and nonlinear filtering strategies based on the Normal Distribution Fiber Optimization (NDFO) material interpolation scheme to overcome the challenge of discrete fiber optimization results, which are difficult to apply directly to continuous fiber additive manufacturing. With minimizing structural compliance as the objective function, the proposed approach provides a strategy to achieve continuity of discrete fiber paths in the variable stiffness design optimization of composite laminates with regular and irregular holes. In the variable stiffness design optimization model, the number of candidate fiber laying angles in the NDFO material interpolation scheme is considered as design variable. The sensitivity information of structural compliance with respect to the number of candidate fiber laying angles is obtained using the analytical sensitivity analysis method. Based on the proposed variable stiffness design optimization method for complex perforated composite laminates, the numerical examples consider the variable stiffness design optimization of typical non-perforated and perforated composite laminates with circular, square, and irregular holes, and systematically discuss the number of candidate discrete fiber laying angles, discrete fiber continuous filtering strategies, and filter radius on structural compliance, continuity, and manufacturability. The optimized discrete fiber angles of variable stiffness laminates are converted into continuous fiber laying paths using a streamlined process for continuous fiber additive manufacturing. Meanwhile, the optimized non-perforated and perforated MBB beams after discrete fiber continuous treatment, are manufactured using continuous fiber co-extrusion additive manufacturing technology to verify the effectiveness of the variable stiffness fiber optimization framework proposed in this paper. 展开更多
关键词 Variable stiffness composite laminates Discrete material interpolation scheme Normal distribution fiber optimization Discrete fiber continuous filtering strategy Additive manufacturing of composite laminates
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On α-Bloch Functions in Several Complex Variables
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作者 ZHU Ting YANG Liu 《Chinese Quarterly Journal of Mathematics》 2025年第1期93-102,共10页
In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Au... In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Aulaskari-Wulan,and Wu.Some examples are also given to complement our theory. 展开更多
关键词 α-Bloch function Littleα-Bloch function several complex variables Partial derivative
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Effects of Continuous Cropping of Polygonatum odoratum on Microbial Functional Diversity and Selected Environmental Factors in the Rhizosphere Soil
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作者 Manjiang YU Yihong HU +3 位作者 Fan XIE Xiongmei ZHU Chenzhong JIN Jing YE 《Agricultural Biotechnology》 2025年第5期12-18,21,共8页
[Objectives]This study was conducted to investigate the mechanism of continuous cropping obstacles in Polygonatum odoratum.[Methods]Three treatments were established:continuous cropping(two consecutive crops),first-cr... [Objectives]This study was conducted to investigate the mechanism of continuous cropping obstacles in Polygonatum odoratum.[Methods]Three treatments were established:continuous cropping(two consecutive crops),first-crop control(with Phaseolus vulgaris as the preceding crop),and blank control.The effects of continuous cropping on the functional diversity of soil microorganisms,soil enzyme activities,and soil nutrient coordination in the rhizosphere soil of P.odoratum during different growth stages were investigated.[Results](1)Continuous cropping increased the carbon source metabolic capacity,Shannon diversity index,and richness of rhizosphere soil microorganisms by 3.2%-14.7%,0.9%-3.5%,and 1.3%-12.5%,respectively,but the differences were not significant.(2)Principal component analysis indicated that during the middle stage of rhizome expansion,continuous cropping significantly altered the characteristics of microbial carbon metabolism,and the microbial communities utilizing carbohydrates,amino acids,polymers,carboxylic acids and amines as carbon sources exhibited vigorous metabolism.(3)Continuous cropping significantly reduced the activities of urease,polyphenol oxidase,and acid phosphatase in rhizosphere soil,with decreases of 24.4%-39.5%,3.2%-14.8%,and 7.9%-18.2%,respectively.The activities of catalase and invertase sometimes exceeded and sometimes fell below those of the first crop,showing no consistent pattern.(4)Under continuous cropping conditions,nutrient imbalance occurred in the rhizosphere soil,characterized by nitrogen deficiency and phosphorus surplus.(5)Grey correlation analysis indicated that available phosphorus content,alkali-hydrolyzable nitrogen content and polyphenol oxidase activity in rhizosphere soil were the main factors influencing microbial functional diversity.[Conclusions]This study provides a theoretical basis for understanding the formation mechanism of continuous cropping obstacles in P.odoratum. 展开更多
关键词 Polygonatum odoratum Continuous cropping Rhizosphere soil Microbial function
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Evaluating the Impact of Different Electrocardiogram Methods on Detecting Pacemaker Dysfunction and Cardiac Function Changes in Pacemaker Patients
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作者 Yan Li Chun Zhou +1 位作者 Ying Li Binlin Chen 《Journal of Clinical and Nursing Research》 2025年第8期7-13,共7页
Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation... Objective:To investigate the effect of 12-lead electrocardiogram and 24-hour dynamic electrocardiogram in detecting pacemaker dysfunction and changes in cardiac function indexes in patients with pacemaker implantation.Methods:A total of 136 patients with pacemaker implantation in the First Clinical Medical College of Three Gorges University,Institute of Cardiovascular Disease of Three Gorges University and Yicang Central People’s Hospital from January 2023 to December 2024 were selected as the research objects.All patients received 12-lead electrocardiogram and 24-hour holter 3–14 days after implantation.Results:The overall detection rate of various types of pacemaker dysfunction by Holter was significantly higher than that by conventional ECG(27.21%vs.5.15%,χ^(2)=24.402,P<0.001).The overall arrhythmia detection rate of Holter was significantly higher than that of conventional electrocardiogram(57.35%vs.10.29%,χ^(2)=67.277,P<0.001).The time domain indexes of heart rate variability obtained by 24-hour continuous monitoring of Holter were significantly improved compared with those of conventional electrocardiogram(P<0.05).Conclusions:Compared with 12-lead electrocardiogram,24-hour holter monitoring can more accurately detect pacemaker dysfunction and arrhythmia in patients with pacemaker implantation,and provide more comprehensive data of heart rate variability,which is helpful for clinicians to better evaluate the cardiac function of patients and adjust treatment plans. 展开更多
关键词 Pacemaker implantation ELECTROCARDIOGRAM Abnormal pacemaker function Cardiac arrhythmia Heart rate variability
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Association of heart rate variability index with depressive symptoms and lung function in chronic obstructive pulmonary disease
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作者 Ya-Ping Yang Mei-Jia Ji +1 位作者 Yue-Han Guo Na Yao 《World Journal of Psychiatry》 2025年第5期127-135,共9页
BACKGROUND Depression is a common comorbidity in patients with chronic obstructive pulmonary disease(COPD).Research indicates that COPD affects cardiac au-tonomic control,and heart rate variability(HRV)serves as a sim... BACKGROUND Depression is a common comorbidity in patients with chronic obstructive pulmonary disease(COPD).Research indicates that COPD affects cardiac au-tonomic control,and heart rate variability(HRV)serves as a simple,non-invasive measure of autonomic nerve activity.However,the relationship between HRV and lung function,as well as the impact of depressive symptoms,remains un-clear.METHODS A retrospective cross-sectional study involving 120 COPD patients hospitalized from January 2018 to January 2024 at our institution was conducted.Demographic and clinical characteristics were collected,and depressive symptoms were asse-ssed using the Beck Depression Inventory(BDI).Patients were categorized into a depressed group(BDI≥16)and a non-depressed group(BDI<16).A control group consisting of 60 healthy volunteers who underwent check-ups at the same institution was also included.Statistical analyses were performed using SPSS 26.0 software.Pearson correlation coefficients were calculated to determine and compare the relationships between HRV parameters,lung function measures,and RESULTS Of the 120 patients with COPD,35.8%(43/120)were diagnosed with depression,compared to 5.0%(3/60)in the control group.The HRV index in COPD patients was significantly lower than that in the control group(P<0.05),and the value in the depressed group was significantly lower than that in the non-depressed group(P<0.05).Similarly,the COPD group had a significantly lower pulmonary forced vital capacity(FVC),first-second expiratory volume(FEV1)and FEV1/FVC ratios than the control group(P<0.05),and the depressed group was significantly lower than that in the non-depressed group(P<0.05).Pearson correlation analysis revealed that the standard deviation of normal R-R intervals,standard deviation of the mean of 5-minute normal R-R intervals,root mean square of successive differences of normal R-R intervals,percentage of normal R-R intervals greater than 50 ms,high-frequency,and low-frequency indices showed positive correlations with lung function parameters(P<0.05)and negative correlations with BDI scores(P<0.05).CONCLUSION Compared to patients without COPD,the incidence of depressive symptoms is higher among patients with COPD and is negatively correlated with the patients’HRV indices.In contrast,HRV indices are positively correlated with the patients’pulmonary function parameters.Patients and healthcare professionals should enhance their awareness of depression,actively conduct depression assessment screenings,and incorporate HRV indices into disease management.This approach aims to improve the psychological health of patients and ultimately enhance their prognosis and quality of life. 展开更多
关键词 Chronic obstructive pulmonary disease Heart rate variability Lung function DEPRESSION Beck depression inventory
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The Effect of Continuous Positive Airway Pressure Therapy on Daytime Sleepiness and Cognitive Function in Patients with Moderate to Severe OSAHS
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作者 Juan Du Yinping Wang +2 位作者 Long Zhang Rui Lu Ming Cui 《Science International Innovative Medicine》 2025年第3期17-22,共6页
Objective:To explore the effect of continuous positive airway pressure(CPAP)therapy on daytime sleepiness and cognitive function in patients with moderate to severe obstructive sleep apnea-hypopnea syndrome(OSAHS).Met... Objective:To explore the effect of continuous positive airway pressure(CPAP)therapy on daytime sleepiness and cognitive function in patients with moderate to severe obstructive sleep apnea-hypopnea syndrome(OSAHS).Methods:From January to December 2024,60 patients with moderate to severe OSAHS were enrolled and randomly divided into an observation group and a control group,with 30 patients in each group.The observation group received CPAP combined with routine intervention,while the control group only received routine intervention,with a course of 3 months for both groups.Results:After 3 months of intervention,the observation group showed significantly better improvements in the frequency and duration of daytime sleepiness as well as all dimensions of cognitive function compared with the control group,and the differences were statistically significant(P<0.05).Conclusion:CPAP therapy can effectively relieve daytime sleepiness in patients with moderate to severe OSAHS,and significantly improve memory,attention and logical thinking ability.The comprehensive intervention effect is superior to simple routine management. 展开更多
关键词 Continuous Positive Airway Pressure Obstructive Sleep Apnea-Hypopnea Syndrome Daytime Sleepiness Cognitive function Sleep Quality
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 symmetry group group foliation method nonlinear wave equation functional separation of variables
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SPACES OF ANALYTIC FUNCTIONS REPRESENTED BY DIRICHLET SERIES OF TWO COMPLEX VARIABLES 被引量:1
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作者 Hazem Shaba Behnam and G. S. Srivastava (Indian Institule Technology of Roorkee, India) 《Approximation Theory and Its Applications》 2002年第3期1-14,共14页
We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the auth... We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the authors. Under this topology X becomes a Frechet space Apart from finding the characterization of continuous linear functionals, linear transformation on X, we have obtained the necessary and sufficient conditions for a double sequence in X to be a proper bases. 展开更多
关键词 SPACES of ANALYTIC functionS REPRESENTED BY DIRICHLET SERIES of TWO COMPLEX variables TEB MATH
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Fuzzy Semi-continuity of fuzzy number-valued function 被引量:3
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作者 Magassy OUS MANE 吴从炘 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期139-141,共3页
In this paper we discuss the conecept and property of fuzzy semi continuous function.
关键词 FUZZY NUMBERS FUZZY number-valued function FUZZY SEMI-CONTINUOUS function
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ON THE CONTINUITY AND DIFFERENTIABILITY OF AKIND OF FRACTAL INTERPOLATION FUNCTION
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作者 李红达 叶正麟 高行山 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第4期471-478,共8页
The sufficient conditions of Holder continuity of two kinds of fractal interpolation functions defined by IFS (Iterated Function System) were obtained. The sufficient and necessary condition for its differentiability ... The sufficient conditions of Holder continuity of two kinds of fractal interpolation functions defined by IFS (Iterated Function System) were obtained. The sufficient and necessary condition for its differentiability was proved. Its derivative was a fractal interpolation function generated by the associated IFS, if it is differentiable. 展开更多
关键词 FRACTAL interpolation function Holder continuity DIFFERENTIABILITY
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Lipschitz continuity of the optimal value function and KKT solution set in indefinite quadratic programs
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作者 HAN You-pan CHEN Zhi-ping ZHANG Feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第1期102-110,共9页
When all the involved data in indefinite quadratic programs change simultaneously, we show the locally Lipschtiz continuity of the KKT set of the quadratic programming problem firstly, then we establish the locally Li... When all the involved data in indefinite quadratic programs change simultaneously, we show the locally Lipschtiz continuity of the KKT set of the quadratic programming problem firstly, then we establish the locally Lipschtiz continuity of the KKT solution set. Finally, the similar conclusion for the corresponding optimal value function is obtained. 展开更多
关键词 quadratic program Lipschitz continuity value function feasible solution KKT solution set.
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Continuity of truncated Hardy-Littlewood maximal function
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作者 WANG Yidong WU Jia YAN Dunyan 《中国科学院大学学报(中英文)》 CAS CSCD 北大核心 2024年第6期721-727,共7页
This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of... This paper focuses on the continuity of the truncated Hardy-Littlewood maximal function.We first show that the truncated Hardy-Littlewood maximal function is lower semi-continuous.Then by investigating the behavior of the truncated Hardy-Littlewood maximal function when the truncated parameterγchanges,we obtain an equivalent condition of the continuity of the truncated Hardy-Littlewood maximal function. 展开更多
关键词 Hardy-Littlewood maximal function TRUNCATION continuity truncated parameter
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EFFICIENT ESTIMATION OF FUNCTIONAL-COEFFICIENT REGRESSION MODELS WITH DIFFERENT SMOOTHING VARIABLES 被引量:5
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作者 张日权 李国英 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期989-997,共9页
In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the l... In this article,a procedure for estimating the coefficient functions on the functional-coefficient regression models with different smoothing variables in different coefficient functions is defined.First step,by the local linear technique and the averaged method,the initial estimates of the coefficient functions are given.Second step,based on the initial estimates,the efficient estimates of the coefficient functions are proposed by a one-step back-fitting procedure.The efficient estimators share the same asymptotic normalities as the local linear estimators for the functional-coefficient models with a single smoothing variable in different functions.Two simulated examples show that the procedure is effective. 展开更多
关键词 Asymptotic normality averaged method different smoothing variables functional-coefficient regression models local linear method one-step back-fitting procedure
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Commuting of Toeplitz Operators in Several Complex Variables
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作者 卢玉峰 孙善利 《Northeastern Mathematical Journal》 CSCD 2001年第3期253-256,共4页
关键词 Toeplitz operator COMMUTANT function of several complex variables
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Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function
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作者 Mokhtar Ellali Mokhtar Bouazza Ashraf M.Zenkour 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期547-561,共15页
Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagati... Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in plates.This work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of FGM.This model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine function.The FGM plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse quadratic.By utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials. 展开更多
关键词 FGM plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function
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A SPECIAL MODULUS OF CONTINUITY AND THE K-FUNCTIONAL
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作者 Nadezhda DOLMATOVA 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1531-1540,共10页
We consider the questions connected with the approximation of a real continuous 1-periodic functions and give a new proof of the equivalence of the special Boman-Shapiro modulus of continuity with Peetre’s K-function... We consider the questions connected with the approximation of a real continuous 1-periodic functions and give a new proof of the equivalence of the special Boman-Shapiro modulus of continuity with Peetre’s K-functional. We also prove Jackson’s inequality for the approximation by trigonometric polynomials. 展开更多
关键词 modulus of continuity K-functionAL Jackson's theorem
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Clinical Study on the Effect of Continuity of Care in CICU on Improving Cognitive Function and Psychological State in Patients with Heart Failure
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作者 Jin Sang Yuqing Xie Xintong Zhu 《Journal of Clinical and Nursing Research》 2024年第10期133-139,共7页
Objective:To analyze the effect of continuity of care in the cardiac intensive care unit(CICU)on improving cognitive function and psychological state in patients with heart failure(HF).Methods:A total of 112 chronic H... Objective:To analyze the effect of continuity of care in the cardiac intensive care unit(CICU)on improving cognitive function and psychological state in patients with heart failure(HF).Methods:A total of 112 chronic HF patients admitted to the CICU of Xuzhou Traditional Chinese Medicine Hospital from July 2022 to August 2024 were selected and randomly divided into two groups using the red and blue ball method:a control group(n=56)and a study group(n=56).The control group received routine CICU nursing management,while the study group received routine CICU nursing combined with continuity of care management.Cognitive function(using the Montreal Cognitive Assessment,MoCA),psychological state(using the Self-Rating Depression Scale,SDS,and Self-Rating Anxiety Scale,SAS),and quality of life(using the Minnesota Living with Heart Failure Questionnaire,MLHFQ)were compared between the two groups.Results:After the intervention,the cognitive function scores of the study group were significantly higher than those of the control group(P<0.05).The SDS and SAS scores of the study group were significantly lower than those of the control group after the intervention(P<0.05).The quality of life in the study group was also significantly better than in the control group(P<0.05).Conclusion:CICU continuity of care can effectively improve cognitive function and psychological state in patients with HF,while also enhancing their quality of life. 展开更多
关键词 CICU continuity of care Heart failure patients Cognitive function Psychological state
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Construction of crash prediction model of freeway basic segment based on interactive influence of explanatory variables
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作者 王晓飞 李新伟 +2 位作者 符锌砂 赵立萱 刘小峰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期276-281,共6页
In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomi... In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomial (NB) regression models and three generalized negative binomial (GNB) regression models are built to prove that the interactive influence of explanatory variables plays an important role in fitting goodness. The effective use of the GNB model in analyzing the interactive influence of explanatory variables and predicting freeway basic segments is demonstrated. Among six models, the two models (one is the NB model and the other is the GNB model. ) which consider the interactive influence of the annual average daily traffic (AADT) and length are more reasonable for predicting results. Furthermore, a comprehensive study is carried out to prove that when considering the interactive influence, the NB and GNB models have almost the same fitting performance in estimating the crashes, among which the GNB model is slightly better for prediction performance. 展开更多
关键词 CRASH FREEWAY safety performance function SPF interactive influence of explanatory variables generalized negative binomial (GNB)
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