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A Level-Value Estimate Method for Solving Constrained Global Optimization
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作者 俞武扬 邬冬华 吕瑜佩 《Journal of Shanghai University(English Edition)》 CAS 2004年第2期128-131,共4页
The penalty method is a popular method for solving constrained optimization problems, which can change the constrained optimization to the unconstrained optimization. With the integral-level set method, a new approach... The penalty method is a popular method for solving constrained optimization problems, which can change the constrained optimization to the unconstrained optimization. With the integral-level set method, a new approach was proposed, which is briefer than the penalty method, to achieve the transform by constructing a simple function, then a level-value function was introduced to construct the equivalence between the unconstrained optimization and a nonlinear equality. By studying the properties of the function, a level-value estimate algorithm and an implementation algorithm were given by means of the uniform distribution of the good point set. Key words global optimization - constrained optimization - integral-level set - level-value estimate MSC 2000 90C05 展开更多
关键词 global optimization constrained optimization integral-level set level-value estimate
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STRICHARTZ AND SMOOTHING ESTIMATES FOR DISPERSIVE SEMI-GROUP e^(-itP(D)) IN WEIGHTED L^(2) SPACES AND THEIR APPLICATIONS
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作者 Jiecheng CHEN Shaolei RU Chenjing WU 《Acta Mathematica Scientia》 2025年第2期401-415,共15页
Combining TT* argument and bilinear interpolation,this paper obtains the Strichartz and smoothing estimates of dispersive semigroup e^(-itP(D)) in weighted L^(2) spaces.Among other things,we recover the results in[1].... Combining TT* argument and bilinear interpolation,this paper obtains the Strichartz and smoothing estimates of dispersive semigroup e^(-itP(D)) in weighted L^(2) spaces.Among other things,we recover the results in[1].Moreover,the application of these results to the well-posedness of some equations are shown in the last section. 展开更多
关键词 Strichartz estimates smoothing estimates Morrey-Campanato class weighted L^(2)spaces WELL-POSEDNESS
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Space and time estimates of second gradient thermal problems
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作者 J.R.FERNÁNDEZ V.PATA R.QUINTANILLA 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1403-1416,共14页
We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are ... We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are obtained for both the thermal equation and the one-dimensional thermoelastic system,where the impossibility of localization with respect to time is also established.Then,the space estimates are deduced for the multidimensional thermoelastic problem,which allow to show the exponential decay of the energy. 展开更多
关键词 second gradient theory THERMOELASTICITY spatial estimate polynomial decay
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The estimation method is the primary source of uncertainty in cropland nitrate leaching estimates in China
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作者 Xingshuai Tian Huitong Yu +4 位作者 Jiahui Cong Yulong Yin Kai He Zihan Wang Zhenling Cui 《Journal of Integrative Agriculture》 2025年第6期2425-2437,共13页
Cropland nitrate leaching is the major nitrogen(N) loss pathway, and it contributes significantly to water pollution. However, cropland nitrate leaching estimates show great uncertainty due to variations in input data... Cropland nitrate leaching is the major nitrogen(N) loss pathway, and it contributes significantly to water pollution. However, cropland nitrate leaching estimates show great uncertainty due to variations in input datasets and estimation methods. Here, we presented a re-evaluation of Chinese cropland nitrate leaching, and identified and quantified the sources of uncertainty by integrating three cropland area datasets, three N input datasets, and three estimation methods. The results revealed that nitrate leaching from Chinese cropland averaged 6.7±0.6 Tg N yr^(-1)in 2010, ranging from 2.9 to 15.8 Tg N yr^(-1)across 27 different estimates. The primary contributor to the uncertainty was the estimation method, accounting for 45.1%, followed by the interaction of N input dataset and estimation method at 24.4%. The results of this study emphasize the need for adopting a robust estimation method and improving the compatibility between the estimation method and N input dataset to effectively reduce uncertainty. This analysis provides valuable insights for accurately estimating cropland nitrate leaching and contributes to ongoing efforts that address water pollution concerns. 展开更多
关键词 cropland nitrate leaching UNCERTAINTY cropland area nitrogen input estimation method
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Asymptotically Exact a Posteriori Error Estimates for Non-Symmetric Eigenvalue Problems
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作者 Jun ZHANG Jiayu HAN 《Journal of Mathematical Research with Applications》 2025年第3期411-426,共16页
This paper is devoted to the Polynomial Preserving Recovery (PPR) based a posteriori error analysis for the second-order elliptic non-symmetric eigenvalue problem. An asymptotically exact a posteriori error estimator ... This paper is devoted to the Polynomial Preserving Recovery (PPR) based a posteriori error analysis for the second-order elliptic non-symmetric eigenvalue problem. An asymptotically exact a posteriori error estimator is proposed for solving the convection-dominated non-symmetric eigenvalue problem with non-smooth eigenfunctions or multiple eigenvalues. Numerical examples confirm our theoretical analysis. 展开更多
关键词 Polynomial Preserving Recovery non-symmetric eigenvalue problem a posteriori error estimates
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Estimating the final fatalities using early reported death count from the 2023 Kahramanmaras,Türkiye,M_(S) 8.0-7.9 earthquake doublet and revising the estimates over time
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作者 Yan Liu Zitao Wang Xuemin Zhang 《Earthquake Research Advances》 2025年第2期5-12,共8页
Earthquakes can cause significant damage and loss of life,necessitating immediate assessment of the resulting fatalities.Rapid assessment and timely revision of fatality estimates are crucial for effective emergency d... Earthquakes can cause significant damage and loss of life,necessitating immediate assessment of the resulting fatalities.Rapid assessment and timely revision of fatality estimates are crucial for effective emergency decisionmaking.This study using the February 6,2023,M_(S)8.0 and M_(S)7.9 Kahramanmaras,Türkiye earthquakes as an example to estimate the ultimate number of fatalities.An early Quick Rough Estimate(QRE)based on the number of deaths reported by the Disaster and Emergency Management Presidency of Türkiye(AFAD)is conducted,and it dynamically adjusts these estimates as new data becomes available.The range of estimates of the final number of deaths can be calculated as 31384–56475 based on the"the QRE of the second day multiplied by 2–3" rule,which incorporates the reported final deaths 50500.The Quasi-Linear and Adaptive Estimation(QLAE)method adaptively adjusts the final fatality estimate within two days and predicts subsequent reported deaths.The correct order of magnitude of the final death toll can be estimated as early as 13 hr after the M_(S)8.0 earthquake.In addition,additional earthquakes such as May 12,2008,M_(S)8.1 Wenchuan earthquake(China),September 8,2023,M_(S)7.2 Al Haouz earthquake(Morocco),November 3,2023,M_(S)5.8 Mid-Western Nepal earthquake,December 18,2023,M_(S)6.1 Jishishan earthquake(China),January 1,2024,M_(S)7.2 Noto Peninsula earthquake(Japan)and August 8,2023,Maui,Hawaii,fires are added again to verified the correctness of the model.The fatalities from the Maui fires are found to be approximately equivalent to those resulting from an M_(S)7.4 earthquake.These methods complement existing frameworks such as Quake Loss Assessment for Response and Mitigation(QLARM)and Prompt Assessment of Global. 展开更多
关键词 Kahramanmaras earthquake Earthquake fatality Human loss estimates Seismic risk 2023 Maui fires
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THE A PRIORI ESTIMATES FOR A CLASS OF GENERAL HESSIAN QUOTIENT TYPE EQUATIONS
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作者 Ni XIANG Yuni XIONG Jingyi YAO 《Acta Mathematica Scientia》 2025年第3期867-884,共18页
In this paper, we derive the a priori estimates for a class of more general (k, l)-Hessian quotient type equations involving u and Du on the right hand function. As an application we prove the Liouville theorem depend... In this paper, we derive the a priori estimates for a class of more general (k, l)-Hessian quotient type equations involving u and Du on the right hand function. As an application we prove the Liouville theorem depending on Pogorelov type estimates. On the other hand, we obtain the existence and uniqueness of the k-admissible solution for these general equations with the Neumann boundary condition, based on some growth conditions for the right hand function. 展开更多
关键词 Hessian quotient type equations the a priori estimates Neumann problems Liouville Theorem
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C^(2)estimates for a class of degenerate k-Hessian equations with gradient terms on closed Hermitian manifolds
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作者 WU Hanqing XU Lu 《纯粹数学与应用数学》 2025年第1期25-45,共21页
In this article,we are concerned with the C^(2)estimates for the k-convex solutions of a class of degenerate k-Hessian equations on closed Hermitian manifolds,whose function in the right-hand side is relevant to the u... In this article,we are concerned with the C^(2)estimates for the k-convex solutions of a class of degenerate k-Hessian equations on closed Hermitian manifolds,whose function in the right-hand side is relevant to the unknown function and its gradient.We will get C^(0)estimate by promoting others′results,and get the“HMW estimate”of this equation such that the conditions of using blow-up analysis are satisfied,and the gradient estimate and second-order estimate will be obtained.Such an estimate will be helpful to study the existence for the solution of the equation. 展开更多
关键词 C^(2)estimates degenerate k-Hessian equation closed Hermitian manifold
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ELLIPTIC EQUATION WITH CRITICAL EXPONENT AND DIPOLE POTENTIAL: EXISTENCE AND DECAY ESTIMATES
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作者 Yu SU Zhisu LIU Senli LIU 《Acta Mathematica Scientia》 2025年第2期636-658,共23页
The paper is concerned with a class of elliptic equation with critical exponent and Dipole potential.More precisely,we make use of the refined Sobolev inequality with Morrey norm to obtain the existence and decay prop... The paper is concerned with a class of elliptic equation with critical exponent and Dipole potential.More precisely,we make use of the refined Sobolev inequality with Morrey norm to obtain the existence and decay properties of nonnegative radial ground state solutions. 展开更多
关键词 Dipole potential decay estimation Hardy Sobolev critical exponent Henon Sobolev critical exponent
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CNN-based multi-output regression model to estimate infrastructural surface crack dimensions adopting a generalised patch size and FWHM-based width quantification
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作者 Sudipta Debroy Arjun Sil 《Digital Twins and Applications》 2025年第1期75-102,共28页
To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks o... To cater the need for real-time crack monitoring of infrastructural facilities,a CNN-regression model is proposed to directly estimate the crack properties from patches.RGB crack images and their corresponding masks obtained from a public dataset are cropped into patches of 256 square pixels that are classified with a pre-trained deep convolution neural network,the true positives are segmented,and crack properties are extracted using two different methods.The first method is primarily based on active contour models and level-set segmentation and the second method consists of the domain adaptation of a mathematical morphology-based method known as FIL-FINDER.A statistical test has been performed for the comparison of the stated methods and a database prepared with the more suitable method.An advanced convolution neural network-based multi-output regression model has been proposed which was trained with the prepared database and validated with the held-out dataset for the prediction of crack-length,crack-width,and width-uncertainty directly from input image patches.The pro-posed model has been tested on crack patches collected from different locations.Huber loss has been used to ensure the robustness of the proposed model selected from a set of 288 different variations of it.Additionally,an ablation study has been conducted on the top 3 models that demonstrated the influence of each network component on the pre-diction results.Finally,the best performing model HHc-X among the top 3 has been proposed that predicted crack properties which are in close agreement to the ground truths in the test data. 展开更多
关键词 ablation CNN convolution neural network CRACK crack patch estimation FWHM length multi-output regression segmentation uncertainty WIDTH
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Nonlinear association between estimated plasma volume status and acute kidney injury in acute pancreatitis patients
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作者 Wen Wu Yu-Pei Zhang +4 位作者 Yi-Lan Zhang Xing-Guang Qu Zhao-Hui Zhang Rong Zhang Zhi-Yong Peng 《World Journal of Gastroenterology》 2025年第20期44-60,共17页
BACKGROUND Acute pancreatitis(AP),a severe pancreatic inflammatory condition,with a mor-tality rate reaching up to 40%.Recently,AP shows a steadily elevating prevalence,which causes the greater number of hospital admi... BACKGROUND Acute pancreatitis(AP),a severe pancreatic inflammatory condition,with a mor-tality rate reaching up to 40%.Recently,AP shows a steadily elevating prevalence,which causes the greater number of hospital admissions,imposing the substantial economic burden.Acute kidney injury(AKI)complicates take up approximately 15%of AP cases,with an associated mortality rate of 74.7%-81%.AIM To evaluate the efficacy of estimated plasma volume status(ePVS)in forecasting AKI in patients with AP.METHODS In this retrospective cohort study,AP cases were recruited from the First College of Clinical Medical Science of China Three Gorges University between January 2019 and October 2023.Electronic medical records were adopted for data extrac-tion,including demographic data and clinical characteristics.The association between ePVS and AKI was analyzed using multivariate logistic regression models,with potential confounders being adjusted.Nonlinear relationship was examined with smooth curve fitting,and infection points were calculated.Further analyses were performed on stratified subgroups and interaction tests were conducted.RESULTS Among the 1508 AP patients,251(16.6%)developed AKI.ePVS was calculated using Duarte(D-ePVS)and Kaplan-Hakim(KH-ePVS)formulas.After adjusting for covariates,the AKI risk exhibited 46%[odds ratio(OR)=1.46,95%confidence interval(CI):0.96-2.24]and 11%(OR=1.11,95%CI:0.72-1.72)increases in the low tertile(T1)of D-ePVS and KH-ePVS,respectively,and 101%(OR=2.01,95%CI:1.31-3.05)and 51%(OR=1.51,95%CI:1.00-2.29)increases in the high tertile(T3)relative to the reference tertile(T2).Nonlinear curve fitting revealed a U-shaped association of D-ePVS with AKI and a J-shaped association for KH-ePVS,with inflection points at 4.3 dL/g and-2.8%,res-pectively.Significant interactions were not observed in age,gender,hypertension,diabetes mellitus,sequential organ failure assessment score,or AP severity(all P for interaction>0.05).CONCLUSION Our results indicated that ePVS demonstrated the nonlinear association with AKI incidence in AP patients.A U-shaped curve was observed with an inflection point at 4.3 dL/g for the Duarte formula,and a J-shaped curve at-2.8%for the Kaplan-Hakim formula. 展开更多
关键词 Acute pancreatitis Acute kidney injury estimated plasma volume status Cohort study Duarte formula Kaplan-Hakim formula
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Improving the utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates 被引量:1
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作者 Héber H.Arcolezi Jean-François Couchot +1 位作者 Bechara Al Bouna Xiaokui Xiao 《Digital Communications and Networks》 SCIE CSCD 2024年第2期369-379,共11页
This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)guarantees.Contra... This paper investigates the problem of collecting multidimensional data throughout time(i.e.,longitudinal studies)for the fundamental task of frequency estimation under Local Differential Privacy(LDP)guarantees.Contrary to frequency estimation of a single attribute,the multidimensional aspect demands particular attention to the privacy budget.Besides,when collecting user statistics longitudinally,privacy progressively degrades.Indeed,the“multiple”settings in combination(i.e.,many attributes and several collections throughout time)impose several challenges,for which this paper proposes the first solution for frequency estimates under LDP.To tackle these issues,we extend the analysis of three state-of-the-art LDP protocols(Generalized Randomized Response–GRR,Optimized Unary Encoding–OUE,and Symmetric Unary Encoding–SUE)for both longitudinal and multidimensional data collections.While the known literature uses OUE and SUE for two rounds of sanitization(a.k.a.memoization),i.e.,L-OUE and L-SUE,respectively,we analytically and experimentally show that starting with OUE and then with SUE provides higher data utility(i.e.,L-OSUE).Also,for attributes with small domain sizes,we propose Longitudinal GRR(L-GRR),which provides higher utility than the other protocols based on unary encoding.Last,we also propose a new solution named Adaptive LDP for LOngitudinal and Multidimensional FREquency Estimates(ALLOMFREE),which randomly samples a single attribute to be sent with the whole privacy budget and adaptively selects the optimal protocol,i.e.,either L-GRR or L-OSUE.As shown in the results,ALLOMFREE consistently and considerably outperforms the state-of-the-art L-SUE and L-OUE protocols in the quality of the frequency estimates. 展开更多
关键词 Local differential privacy Discrete distribution estimation Frequency estimation Multidimensional data Longitudinal studies
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Genetic and Agronomic Parameter Estimates of Growth, Yield and Related Traits of Maize (Zea mays L.) under Different Rates of Nitrogen Fertilization 被引量:1
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作者 Prince Emmanuel Norman Lansana Kamara +6 位作者 Aloysius Beah Kelvin Sahr Gborie Francess Sia Saquee Sheku Alfred Kanu Fayia Augustine Kassoh Yvonne Sylvia Gloria Ethel Norman Abdul Salaam Kargbo 《American Journal of Plant Sciences》 CAS 2024年第4期274-291,共18页
This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in... This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup>) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p < 0.05) influenced grain yield production. Mean grain yields and economic parameter estimates increased with increasing nitrogen rates, with the 30 and 180 kg∙N∙ha<sup>−</sup><sup>1</sup> plots exhibiting the lowest and highest grain yields of 1238 kg∙ha<sup>−</sup><sup>1</sup> and 2098 kg∙ha<sup>−</sup><sup>1</sup>, respectively. Variety and nitrogen effects on partial factor productivity (PFP<sub>N</sub>), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p < 0.05) by these factors. The highest PFP<sub>N</sub> (41.3 kg grain kg<sup>−</sup><sup>1</sup>∙N) and AEN (29.4 kg grain kg<sup>−</sup><sup>1</sup>∙N) were obtained in the 30 kg∙N∙ha<sup>−</sup><sup>1</sup> plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL<sup>−</sup><sup>1</sup> spent on N) were obtained in the 180 kg∙N∙ha<sup>−</sup><sup>1</sup>. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fertilization and improved farming practices that could be exploited for increased productivity of maize. 展开更多
关键词 Nitrogen Rates Genetic and Agronomic estimates Introduced Genotypes Grain Yield Zea mays
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Trial characteristics and treatment effect estimates in randomized controlled trials of Chinese herbal medicine: A meta-epidemiological study 被引量:2
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作者 Betty H.Wang Ya-li Lin +10 位作者 Yin-yan Gao Jin-lu Song Lang Qin Ling-qi Li Wen-qi Liu Claire C.W.Zhong Mary Y.Jiang Chen Mao Xiao-bo Yang Vincent C.H.Chung Irene X.Y.Wu 《Journal of Integrative Medicine》 SCIE CAS CSCD 2024年第3期223-234,共12页
Background:Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials(RCTs).Nevertheless,i... Background:Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials(RCTs).Nevertheless,it remains unclear if similar associations exist in RCTs on Chinese herbal medicine(CHM).Further,Chinese medicine-related characteristics have not been explored yet.Objective:To investigate trial characteristics related to treatment effect estimates on CHM RCTs.Search strategy:This meta-epidemiological study searched 5 databases for systematic reviews on CHM treatment published between January 2011 and July 2021.Inclusion criteria:An eligible systematic review should only include RCTs of CHM and conduct at least one meta-analysis.Data extraction and analysis:Two reviewers independently conducted data extraction on general characteristics of systematic reviews,meta-analyses and included RCTs.They also assessed the risk of bias of RCTs using the Cochrane risk of bias tool.A two-step approach was used for data analyses.The ratio of odds ratios(ROR) and difference in standardized mean differences (dSMD) with 95%confidence interval (CI) were applied to present the difference in effect estimates for binary and continuous outcomes,respectively.Results:Ninety-one systematic reviews,comprising 1338 RCTs were identified.For binary outcomes,RCTs incorporated with syndrome differentiation (ROR:1.23;95%CI:[1.07,1.39]),adopting Chinese medicine formula (ROR:1.19;95%CI:[1.03,1.34]),with low risk of bias on incomplete outcome data (ROR:1.29;95%CI:[1.06,1.52]) and selective outcome reporting (ROR:1.12;95%CI:[1.01,1.24]),as well as a trial size≥100 (ROR:1.23;95%CI:[1.04,1.42]) preferred to show larger effect estimates.As for continuous outcomes,RCTs with Chinese medicine diagnostic criteria (dSMD:0.23;95%CI:[0.06,0.41]),judged as high/unclear risk of bias on allocation concealment (dSMD:-0.70;95%CI:[-0.99,-0.42]),with low risk of bias on incomplete outcome data (dSMD:0.30;95%CI:[0.18,0.43]),conducted at a single center (dSMD:-0.33;95%CI:[-0.61,-0.05]),not using intention-to-treat analysis (dSMD:-0.75;95%CI:[-1.43,-0.07]),and without funding support (dSMD:-0.22;95%CI:[-0.41,-0.02]) tended to show larger effect estimates.Conclusion:This study provides empirical evidence for the development of a specific critical appraisal tool for risk of bias assessments on CHM RCTs. 展开更多
关键词 Chinese herbal medicine Randomized controlled trial Risk of bias Meta-epidemiological study Effect estimates
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A LEVEL-VALUE ESTIMATION METHOD FOR SOLVING GLOBAL OPTIMIZATION 被引量:1
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作者 邬冬华 俞武扬 +1 位作者 田蔚文 张连生 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第7期1001-1010,共10页
A level-value estimation method was illustrated for solving the constrained global optimization problem. The equivalence between the root of a modified variance equation and the optimal value of the original optimizat... A level-value estimation method was illustrated for solving the constrained global optimization problem. The equivalence between the root of a modified variance equation and the optimal value of the original optimization problem is shown. An alternate algorithm based on the Newton's method is presented and the convergence of its implementable approach is proved. Preliminary numerical results indicate that the method is effective. 展开更多
关键词 global optimization level-value estimation uniform distribution
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Machine learning-based comparison of factors influencing estimated glomerular filtration rate in Chinese women with or without nonalcoholic fatty liver 被引量:1
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作者 I-Chien Chen Lin-Ju Chou +2 位作者 Shih-Chen Huang Ta-Wei Chu Shang-Sen Lee 《World Journal of Clinical Cases》 SCIE 2024年第15期2506-2521,共16页
BACKGROUND The prevalence of non-alcoholic fatty liver(NAFLD)has increased recently.Subjects with NAFLD are known to have higher chance for renal function impairment.Many past studies used traditional multiple linear ... BACKGROUND The prevalence of non-alcoholic fatty liver(NAFLD)has increased recently.Subjects with NAFLD are known to have higher chance for renal function impairment.Many past studies used traditional multiple linear regression(MLR)to identify risk factors for decreased estimated glomerular filtration rate(eGFR).However,medical research is increasingly relying on emerging machine learning(Mach-L)methods.The present study enrolled healthy women to identify factors affecting eGFR in subjects with and without NAFLD(NAFLD+,NAFLD-)and to rank their importance.AIM To uses three different Mach-L methods to identify key impact factors for eGFR in healthy women with and without NAFLD.METHODS A total of 65535 healthy female study participants were enrolled from the Taiwan MJ cohort,accounting for 32 independent variables including demographic,biochemistry and lifestyle parameters(independent variables),while eGFR was used as the dependent variable.Aside from MLR,three Mach-L methods were applied,including stochastic gradient boosting,eXtreme gradient boosting and elastic net.Errors of estimation were used to define method accuracy,where smaller degree of error indicated better model performance.RESULTS Income,albumin,eGFR,High density lipoprotein-Cholesterol,phosphorus,forced expiratory volume in one second(FEV1),and sleep time were all lower in the NAFLD+group,while other factors were all significantly higher except for smoking area.Mach-L had lower estimation errors,thus outperforming MLR.In Model 1,age,uric acid(UA),FEV1,plasma calcium level(Ca),plasma albumin level(Alb)and T-bilirubin were the most important factors in the NAFLD+group,as opposed to age,UA,FEV1,Alb,lactic dehydrogenase(LDH)and Ca for the NAFLD-group.Given the importance percentage was much higher than the 2nd important factor,we built Model 2 by removing age.CONCLUSION The eGFR were lower in the NAFLD+group compared to the NAFLD-group,with age being was the most important impact factor in both groups of healthy Chinese women,followed by LDH,UA,FEV1 and Alb.However,for the NAFLD-group,TSH and SBP were the 5th and 6th most important factors,as opposed to Ca and BF in the NAFLD+group. 展开更多
关键词 Non-alcoholic fatty liver estimated glomerular filtration rate Machine learning Chinese women
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Detection of decline in estimated glomerular filtration rate in patients with type 2 diabetes by cystatin C-based equations 被引量:2
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作者 Tam Thai Thanh Tran Tien Kim Ha +2 位作者 Nhut Minh Phan Minh Van Le Tin Hoang Nguyen 《World Journal of Nephrology》 2024年第4期103-116,共14页
BACKGROUND Aging population is a significant issue in Viet Nam and across the globe.Elderly individuals are at higher risk of chronic kidney disease(CKD),especially those with diabetes.Several studies found that the e... BACKGROUND Aging population is a significant issue in Viet Nam and across the globe.Elderly individuals are at higher risk of chronic kidney disease(CKD),especially those with diabetes.Several studies found that the estimated glomerular filtration rate(eGFR)determined using creatinine-based equations was not as accurate as that determined using cystatin C-based equations.Cystatin C-based equations may be beneficial in elderly patients with an age-associated decline in kidney function.Early determination of eGFR decline and associated factors would aid in appropriate interventions to improve kidney function in elderly patients with diabetes.AIM To determine the utility of cystatin C-based equations in early detection of eGFR decline and to explore factors associated with eGFR decline in elderly patients with diabetes.METHODS This cross-sectional study included 93 participants aged≥60 years evaluated in Can Tho University of Medicine and Pharmacy Hospital between October 2022 and July 2023,including 47 and 46 participants with and without diabetes respectively,according to the American Diabetes Association criteria for diabetes.The kappa coefficient,Student’s t,Mann-Whitney,χ2,Pearson’s correlation,multivariate logistic regression,and multiple linear regression analyses were employed.RESULTS The eGFRs were lower with the cystatin C-based equations than with the creatinine-based equations.Good agreement was found between the Modification of Diet in Renal Disease(MDRD)and CKD Epidemiology Collaboration(CKD-EPI)2021 creatinine-cystatin C equations(kappa=0.66).In the diabetes group,30%of the participants had low eGFR.Both plasma glucose and glycated hemoglobin were associated with an increased risk of eGFR decline(P<0.05)and negatively correlated with eGFR(P=0.001).By multivariate logistic regression,total cholesterol,and exercise were independently associated with low eGFR.By multiple linear regression,higher plasma glucose levels were correlated with lower eGFR(P=0.026,r=-0.366).CONCLUSION Cystatin C-based equations were superior in the early detection of a decline in eGFR,and the MDRD equation may be considered as an alternative to the CKD-EPI 2021 creatinine-cystatin C equation.Exercise,plasma glucose,and total cholesterol were independently associated with eGFR in patients with diabetes. 展开更多
关键词 Cystatin C estimated glomerular filtration rate ELDERLY DIABETES NEPHROLOGY Kidney function
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A Novel Self-Supervised Learning Network for Binocular Disparity Estimation 被引量:1
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作者 Jiawei Tian Yu Zhou +5 位作者 Xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu Lu Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期209-229,共21页
Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This st... Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical robots.This study proposes a novel end-to-end disparity estimation model to address these challenges.Our approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting interferences.This study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and efficiency.The model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video data.Experimental results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing parameters.Moreover,the model exhibited faster convergence during training,contributing to overall performance enhancement.This study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments. 展开更多
关键词 Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation
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Unconditional and Optimal Pointwise Error Estimates of Finite Difference Methods for the Two-Dimensional Complex Ginzburg-Landau Equation
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作者 Yue CHENG Dongsheng TANG 《Journal of Mathematical Research with Applications》 CSCD 2024年第2期248-268,共21页
In this paper,we give improved error estimates for linearized and nonlinear CrankNicolson type finite difference schemes of Ginzburg-Landau equation in two dimensions.For linearized Crank-Nicolson scheme,we use mathem... In this paper,we give improved error estimates for linearized and nonlinear CrankNicolson type finite difference schemes of Ginzburg-Landau equation in two dimensions.For linearized Crank-Nicolson scheme,we use mathematical induction to get unconditional error estimates in discrete L^(2)and H^(1)norm.However,it is not applicable for the nonlinear scheme.Thus,based on a‘cut-off’function and energy analysis method,we get unconditional L^(2)and H^(1)error estimates for the nonlinear scheme,as well as boundedness of numerical solutions.In addition,if the assumption for exact solutions is improved compared to before,unconditional and optimal pointwise error estimates can be obtained by energy analysis method and several Sobolev inequalities.Finally,some numerical examples are given to verify our theoretical analysis. 展开更多
关键词 complex Ginzburg-Landau equation finite difference method unconditional convergence optimal estimates pointwise error estimates
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A Formulation of the Porous Medium Equation with Time-Dependent Porosity: A Priori Estimates and Regularity Results
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作者 Koffi B. Fadimba 《Applied Mathematics》 2024年第10期745-763,共19页
We consider a generalized form of the porous medium equation where the porosity ϕis a function of time t: ϕ=ϕ(x,t): ∂(ϕS)∂t−∇⋅(k(S)∇S)=Q(S).In many works, the porosity ϕis either assumed to be independent of (or to de... We consider a generalized form of the porous medium equation where the porosity ϕis a function of time t: ϕ=ϕ(x,t): ∂(ϕS)∂t−∇⋅(k(S)∇S)=Q(S).In many works, the porosity ϕis either assumed to be independent of (or to depend very little of) the time variable t. In this work, we want to study the case where it does depend on t(and xas well). For this purpose, we make a change of unknown function V=ϕSin order to obtain a saturation-like (advection-diffusion) equation. A priori estimates and regularity results are established for the new equation based in part on what is known from the saturation equation, when ϕis independent of the time t. These results are then extended to the full saturation equation with time-dependent porosity ϕ=ϕ(x,t). In this analysis, we make explicitly the dependence of the various constants in the estimates on the porosity ϕby the introduced transport vector w, through the change of unknown function. Also we do not assume zero-flux boundary, but we carry the analysis for the case Q≡0. 展开更多
关键词 Porous Medium Equation POROSITY Saturation Equation A Priori estimates Regularity Results
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