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A General Association Test for High-Dimensional Random Vectors

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Acta Mathematica Sinica,English Series 2025年

作者： Yongshuai Chen Peng Lin Baoxue Zhang School of Statistics Capital University of Economics and Business

Testing the association of two high-dimensional random vectors is of fundamental importance in the statistical theory and applications. In this paper, we propose a new test statistic based on the Frobenius norm and subtracting bias technique, which is generally applicable to high-dimensional data without restricting the distributional assumptions. The limiting null distribution of the proposed test is shown to be a random variable combining a finite chi-squared-type mixture with a normal approximation. Our proposed test method can also be a normal approximation or a finite chi-squared-type mixtures under additional regularity conditions. To make the test statistic applicable, we introduce a wild bootstrap method and demonstrate its validity. The finite-sample performance of the proposed test via Monte Carlo simulations reveals that it performs better at controlling the empirical size than some existing tests, even when the normal approximation is invalid. Real data analysis is devoted to illustrating the proposed test.

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Orbits of Jacobi forms and theta relations

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Science China Mathematics 2025年

作者： Valery Gritsenko Haowu Wang Laboratoire Paul Painlevé Université de Lille International Laboratory for Mirror Symmetry and Automorphic Forms National Research University Higher School of Economics School of Mathematics and Statistics Wuhan University

Jacobi theta functions with rational characteristics can be viewed as vector-valued Jacobi *** relations usually correspond to different constructions of certain Jacobi forms. From this observation, we extract a new approach, which is called orbits of Jacobi forms, to produce identities on Jacobi theta *** approach not only provides simple proofs of many known theta relations but also produces a large number of new identities, which can be considered as generalizations of Riemann’s theta relations.

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Improving the Position Accuracy and Computational Efficiency of UAV Terrain Aided Navigation Using a Two-Stage Hybrid Fuzzy Particle Filtering Method

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Computers, Materials & Continua 2025年第1期82卷 1193-1210页

作者： Sofia Yousuf Muhammad Bilal Kadri College of Engineering Karachi Institute of Economics&TechnologyKarachi75190Pakistan College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia

Terrain Aided Navigation(TAN)technology has become increasingly important due to its effectiveness in environments where Global Positioning System(GPS)is *** recent years,TAN systems have been extensively researched for both aerial and underwater navigation ***,many TAN systems that rely on recursive Unmanned Aerial Vehicle(UAV)position estimation methods,such as Extended Kalman Filters(EKF),often face challenges with divergence and instability,particularly in highly non-linear *** address these issues,this paper proposes and investigates a hybrid two-stage TAN positioning system for UAVs that utilizes Particle *** enhance the system’s robustness against uncertainties caused by noise and to estimate additional system states,a Fuzzy Particle Filter(FPF)is employed in the first *** approach introduces a novel terrain composite feature that enables a fuzzy expert system to analyze terrain non-linearities and dynamically adjust the number of particles in *** design allows the UAV to be efficiently localized in GPS-denied environments while also reducing the computational complexity of the particle filter in real-time *** the second stage,an Error State Kalman Filter(ESKF)is implemented to estimate the UAV’s *** ESKF is chosen over the conventional EKF method because it is more suitable for non-linear *** results demonstrate that the proposed fuzzy-based terrain composite method achieves high positional accuracy while reducing computational time and memory usage.

关键词： Sensor fusion fuzzy logic particle filter composite feature terrain aided navigation

Temporal variation of major nutrients and probabilistic eutrophication evaluation based on stochastic-fuzzy method in Honghu Lake, Middle China

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Science China(Technological Sciences) 2019年第3期62卷 417-426页

作者： LI Fei QIU ZhenZhen ZHANG JingDong LIU ChaoYang CAI Ying XIAO MinSi ZHU LiYun research Center for Environment and health Zhongnan University of Economics and Law School of Information and Safety Engineering Zhongnan University of Economics and Law

Honghu Lake, which is listed in the Ramsar Convention, was found to be contaminated with elevated nutrients to a certain *** study investigated the seasonal variation of major nutrients and probabilistic eutrophic state in surface water from Honghu Lake. Average concentrations of total nitrogen(TN), total phosphorus(TP), chlorophyll-a(Chl-a), chemical oxygen demand(COD_(Mn)) and transparency(SD) in summer and winter generally exceeded Grade III of the Chinese environmental quality standards for surface water(GB 3838-2002), with the exception of COD_(Mn)in winter. Mean concentrations of Chl-a and COD_(Mn) in summer were higher than that in winter, while mean concentrations of TN, TP and SD were slightly higher in winter. The improved probabilistic comprehensive trophic level index(PTLI) method based on stochastic-fuzzy theory was established to evaluate the eutrophic state in Honghu Lake. Compared with the Monte-Carlo sampling method, the Latin Hypercube sampling(LH-TFN) method was selected for the evaluation simulation due to its efficiency and stability. Evaluation results indicated that mean PTLI in summer(69.70) and winter(61.96) were both subordinated to Grade IV(Medium eutrophication). The corresponding reliability of eutrophication level subordinating to Grade IV in summer was of relatively low reliability(51.27%),which might mislead decision makers to some extent and suggest recheck. The probabilistic eutrophication level in summer developed with a trend from medium to severe eutrophication. Sensitivity analysis illustrated that COD_(Mn)and Chl-a were the priority pollutants in summer, with the contributions to PTLI of 43.3% and 22.5% respectively. Chl-a was the priority pollutant in winter, with the contribution to PTLI up to 51.3%.

关键词： surface water Honghu Lake seasonal variation eutrophic state stochastic-fuzzy theory

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Accuracy and Consistency of the Explicit-Invariant Energy Quadratization Approach for the Cahn-Hilliard Equation

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Journal of Mathematical research with Applications 2025年第1期 84-104页

作者： Jun ZHANG Fangying SONG Yu ZHANG Computational Mathematics research Center Guizhou University of Finance and Economics School of mathematics and statistics Guizhou University of Finance and Economics School of Mathematics and Stastistics Fuzhou University

It is well known that the explicit-invariant energy quadratization (EIEQ) approach can generate fully decoupled, linear and unconditionally energy-stable numerical schemes, so it is favored by many researchers. However, the undeniable fact is that the numerical method obtained by EIEQ approach preserves the “modified” energy law instead of the original *** is mainly due to the introduction of some auxiliary variables in EIEQ scheme, and the truncation error will make the auxiliary variables deviate from the original definition in the process of numerical calculation. The primary objective of this paper is to address this gap by providing the accuracy and consistency of the EIEQ method in the context of the CahnHilliard equation. We introduce a relaxation technique for auxiliary variables and construct two numerical schemes based on EIEQ. The analysis results show that the newly constructed schemes are not only unconditionally energy stable, linear and fully decoupled, but also can effectively correct the errors introduced by auxiliary variables and follow the original energy ***, several 2D and 3D numerical examples illustrate the accuracy and efficiency of the newly constructed numerical schemes.

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Better nutrition, healthier mind? Experimental evidence from primary schools in rural northwestern China

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Journal of Integrative Agriculture 2019年第8期18卷 1768-1779页

作者： LIU Xiao-yue ZHAO Qi-ran CHEN Qi-hui Center for Food and health Economic research College of Economics and Management China Agricultural University

Malnutrition and mental health problems are both prevalent among rural students in China. To provide a better understanding of the functional linkage between these two problems, this study estimates the causal effect of improved nutrition on rural students’ mental health status, exploiting a randomized controlled trial involving 6 044 fourth and fifth graders in rural northwestern China. Estimation results show that a nutrition subsidy provided by the project significantly improved students’ mental health status(measured by their anxiety scale). However, an add-on incentive provided to school principals, which was tied to anemia reduction, almost entirely offset the beneficial impact of the nutrition subsidy. These findings suggest that to improve students’ mental health in rural China, not only direct subsidies, such as low-priced school meals, but also correct incentives, especially those tied closely to students’ mental health outcomes, should be provided.

关键词： malnutrition mental health randomized controlled trial rural China

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Evolutionary Particle Swarm Optimization Algorithm Based on Collective Prediction for Deployment of Base Stations

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Computers, Materials & Continua 2025年第1期82卷 345-369页

作者： Jiaying Shen Donglin Zhu Yujia Liu Leyi Wang Jialing Hu Zhaolong Ouyang Changjun Zhou Taiyong Li School of Computer Science and Technology Zhejiang Normal UniversityJinhua321004China School of Future Technologies Jiangxi Institute of Applied Science and TechnologyNanchang330000China School of Computing and Artificial Intelligence Southwestern University of Finance and EconomicsChengdu611130China

The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real *** development of the Internet of Things(IoT)relies on the support of base stations,which provide a solid foundation for achieving a more intelligent way of *** a specific area,achieving higher signal coverage with fewer base stations has become an urgent ***,this article focuses on the effective coverage area of base station signals and proposes a novel Evolutionary Particle Swarm Optimization(EPSO)algorithm based on collective prediction,referred to herein as *** a new strategy called neighbor-based evolution prediction(NEP)addresses the issue of premature convergence often encountered by *** also employs a strengthening evolution(SE)strategy to enhance the algorithm’s global search capability and efficiency,ensuring enhanced robustness and a faster convergence speed when solving complex optimization *** better adapt to the actual communication needs of base stations,this article conducts simulation experiments by changing the number of base *** experimental results demonstrate thatunder the conditionof 50 ormore base stations,ECPPSOconsistently achieves the best coverage rate exceeding 95%,peaking at 99.4400%when the number of base stations reaches *** results validate the optimization capability of the ECPPSO algorithm,proving its feasibility and *** ablative experiments and comparisons with other algorithms highlight the advantages of ECPPSO.

关键词： Particle swarm optimization effective coverage area global optimization base station deployment

Incidence and risk of herpes zoster in patients with ulcerative colitis and Crohn’s disease in the USA

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Gastroenterology Report 2023年第1期11卷 271-281页

作者： David Singer Philippe Thompson-Leduc Deepshekhar Gupta Wendy Y.Cheng Sara Poston Siyu Ma John E.Pawlowski Mei Sheng Duh Eric D.Morris Francesca Devine Francis A.Farraye US health Outcomes and Epidemiology—Vaccines GSKPhiladelphiaPAUSA health economics and Outcomes research Analysis GroupInc.MontrealQuebecCanada health economics and Outcomes research Analysis GroupInc.Menlo ParkCAUSA health economics and Outcomes research Analysis GroupInc.BostonMAUSA Tufts Medical Center BostonMAUSA Medical Affairs GSKPhiladelphiaPAUSA health economics and Outcomes research Analysis GroupInc.New YorkNYUSA Division of Gastroenterology and Hepatology Mayo ClinicJacksonvilleFLUSA

Background:Patients with inflammatory bowel disease(IBD)are at increased risk of herpes zoster(HZ).We evaluated the incidence of HZ in ulcerative colitis(UC)and Crohn’s disease(CD)patients and compared this with HZ incidence in a non-IBD ***:We conducted a retrospective cohort study(GSK study identifier:VEO-000043)of adults aged18 years with UC and CD and without IBD who were identified from claims recorded in a US healthcare database between October 2015 and February *** HZ incidence rates/1,000 person-years(PY)were calculated,and comparisons of HZ incidence rates between UC or CD and non-IBD cohorts were made using adjusted generalized linear ***:The study population comprised a total of 29,928 UC,25,959 CD,and 11,839,329 non-IBD *** overall HZ incidence rates were 13.64/1,000 PY(UC),15.94/1,000 PY(CD),and 7.95/1,000 PY(non-IBD).UC and CD patients had increased HZ incidence rates,with adjusted incidence rate ratios of 1.35(95%confidence interval[CI],1.26–1.44)and 1.66(95%CI,1.56–1.77),respectively,compared with non-IBD *** analysis indicated increased relative rates of HZ in progressively younger age strata in the UC and CD patients compared with non-IBD *** incidence rates were higher in UC and CD patients who had previously received thiopurines or methotrexate,TNF-inhibitors,or corticosteroids than in UC and CD patients who did not take those ***:UC and CD patients had increased HZ incidence rates compared with patients without IBD,demonstrating the importance of HZ prevention in IBD patients.

关键词： ulcerative colitis Crohn’s disease herpes zoster

Mapping the technology footprint in design for social innovation

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International Journal of Innovation Studies 2022年第3期6卷 216-227页

作者： Chuan Li Guillem Bacete research unit for economics of Culture and Tourism Applied Economics DepartmentUniversity of ValenciaValencia46010Spain

Technology and design are increasingly recognized as important drivers of social innovation(SI).While new-age technologies can disrupt the realm of social innovation through resource-efficient solutions and multiple outcome benefits,the appliction of design thinking approaches and techniques can enhance the potential for SI through humancentered participatory processes and a socially shared vision and *** extensive research focusing on SI practices driven by technology and design respectively,few studies have concentrated on the synergistic effects of technology and design in the field of *** paper addresses this gap through an exploratory study on the incorporation and role of technology in the practice of design for *** applying the mapping approach to a sample of 81 Design-enabled Innovation(DEI)pilot projects in the DESIGNSCAPES project,the distribution,hosts and manifestations of technology footprints are identified,taking into account the multi-phase innovation processes and multifaceted role of *** findings suggest that in design-supported SI,technology can be integrated in a systematic and conventional manner across a range of domains related to people,interactions,contexts,and artefacts and that its interaction with design actions is highly dependent on the different roles of design,followed by a further discussion of a conceptual argument regarding the possible role of technology in supporting design for *** on these findings and results,the article concludes with the limitations of the study and possible theoretical and managerial implications.

关键词： Social innovation Technologyfootprint Design-enabled innovation Design approach Designforsocial innovation Mapping approach