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AERODYNAMIC OPTIMIZATION FOR TURBINE BLADE BASED ON HIERARCHICAL FAIR COMPETITION GENETIC ALGORITHMS WITH DYNAMIC NICHE

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 38-42页

作者： SHU Xinwei GU Chuangang wang tong yang Bo School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

A global optimization approach to turbine blade design based on hierarchical fair competition genetic algorithms with dynamic niche （HFCDN-GAs） coupled with Reynolds-averaged Navier-Stokes （RANS） equation is presented. In order to meet the search theory of GAs and the aerodynamic performances of turbine, Bezier curve is adopted to parameterize the turbine blade profile, and a fitness function pertaining to optimization is designed. The design variables are the control points＇ ordinates of characteristic polygon of Bezier curve representing the turbine blade profile. The object function is the maximum lift-drag ratio of the turbine blade. The constraint conditions take into account the leading and trailing edge metal angle, and the strength and aerodynamic performances of turbine blade. And the treatment method of the constraint conditions is the flexible penalty function. The convergence history of test function indicates that HFCDN-GAs can locate the global optimum within a few search steps and have high robustness. The lift-drag ratio of the optimized blade is 8.3% higher than that of the original one. The results show that the proposed global optimization approach is effective for turbine blade.

关键词： Turbine blade Reynolds-averaged Navier-stokes(RANS) equation Lift-drag ratio Optimum design

DECISION OF SAMPLE SIZES IN EXPERIMENTS OF TURBULENT FLOW BASED ON WAVELET ANALYSIS

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Journal of Hydrodynamics 2006年第3期18卷 324-328页

作者： DAI Zheng-yuan GU Chuan-gang wang tong yang Bo Key Laboratory of Power Machinery and Engineering Ministry of Education Shanghai Jiaotong UniversityShanghai 200030

By making the wavelet analysis in both time and frequency aspect and statistical analysis, a method was proposed to decide sample sizes in the experiments of turbulent flows. With an example of analyzing the turbulent... 详细信息

关键词： turbulence wavelet statistic

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO_(2) photoreduction

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Science China Chemistry 2025年第1期68卷 201-208页

作者： Hui-Feng wang Wen-Jie Shi Yu-Xin yang Bao-Xia Dong tong-Bu Lu Di-Chang Zhong School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Dinuclear metal synergistic catalysis(DMSC)has been proved powerful in boosting CO_(2)reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework(MOF),obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center(M-In),three MOFs with dinuclear homometallic catalytic centers(MM-In),and three MOFs with dinuclear heterometallic catalytic centers(MM’-In,M/M’=Co(II),Ni(II),Zn(II)).It was found that all these MOFs can serve as catalysts for photochemical CO_(2)reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g^(-1)h^(-1),which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO_(2)reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO_(2)reduction.

关键词： metal-organic frameworks dinuclear metal centers synergistic catalysis CO_(2)reduction photocatalysis

Microglia lactylation in relation to central nervous system diseases

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Neural Regeneration Research 2025年第1期20卷 29-40页

作者： Hui yang Nan Mo Le tong Jianhong Dong Ziwei Fan Mengxian Jia Juanqing Yue Ying wang School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Clinical Laboratory The Fourth Clinical Medical College of Zhejiang University of Traditional Chinese Medicine(Hangzhou First People’s Hospital)HangzhouZhejiang ProvinceChina College of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalWestlake University School of MedicineHangzhouZhejiang ProvinceChina

The development of neurodegenerative diseases is closely related to the disruption of central nervous system ***,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative *** has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of *** is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various *** review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting ***,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

关键词： brain central nervous system glycolysis immune response inflammation lactate metabolism lactate lactylation microglia neurodegenerative diseases

High-temperature oxidation behavior and degradation mechanism of chromium-coated zirconium alloy cladding: a review

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Tungsten 2025年第1期7卷 50-70页

作者： Yi Li Bei-Qi wang Xin-Yin Zhang Shi-Jie wang Cong-Yi Li Hui-Long yang Ran-Ran Su tong Liu School of Mechanical Engineering Shanghai Jiao Tong University College and Graduate School of Arts and Sciences University of Virginia Global Institute of Future Technology Shanghai Jiao Tong University

Accident-tolerant fuels(ATF) have been extensively studied to reduce the production rate and total amount of heat and hydrogen generated from high-temperature steam oxidation during severe ***-coated zirconium alloy cladding has become one of the most promising candidates for ATF because of its excellent corrosion and oxidation *** paper provides a comprehensive overview of the research progress on oxidation behaviors and degradation mechanisms in chromium-coated zirconium alloy cladding under high-temperature *** techniques to strengthen the oxidation resistance are highlighted and ***,challenges and opportunities for various future directions are addressed.

关键词： Accident-tolerant fuel Chromium coating Degradation mechanism High-temperature oxidation behavior Zirconium alloy cladding

Recent advances in recurrent hepatocellular carcinoma therapy

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World Journal of Hepatology 2023年第4期15卷 460-476页

作者： Yu-Xue Gao Qi-Qi Ning Peng-Xiang yang Yuan-Yue Guan Peng-Xiang Liu Meng-Lu Liu Lu-Xin Qiao Xiang-Hua Guo tong-wang yang De-Xi Chen Beijing Institute of Hepatology Beijing You An HospitalCapital Medical UniversityBeijing 100069China Beijing Precision Medicine and Transformation Engineering Technology Research Center of Hepatitis and Liver Cancer Beijing 100069China Academician Workstation Changsha Medical UniversityChangsha 410219Hunan ProvinceChina Hunan Key Laboratory of the Research and Development of Novel Pharmaceutical Preparations Changsha Medical UniversityChangsha 410219Hunan ProvinceChina

Hepatocellular carcinoma(HCC)is the most prevalent form of primary liver cancer,accounting for 75%-85%of *** treatments are given to cure early-stage HCC,up to 50%-70%of individuals may experience a relapse of the illness in the liver after 5 *** on the fundamental treatment modalities for recurrent HCC is moving significantly *** precise selection of individuals for therapy strategies with established survival advantages is crucial to ensuring better *** strategies aim to minimize substantial morbidity,support good life quality,and enhance survival for patients with recurrent *** individuals with recurring HCC after curative treatment,no approved therapeutic regimen is currently available.A recent study presented novel approaches,like immunotherapy and antiviral medication,to improve the prognosis of patients with recurring HCC with the apparent lack of data to guide the clinical *** data supporting several neoadjuvant and adjuvant therapies for patients with recurring HCC are outlined in this *** also discuss the potential for future clinical and translational investigations.

关键词： Recurrent hepatocellular carcinoma Liver transplantation Therapy Immunotherapy Neoadjuvant and adjuvant therapy

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng HE Fan yang Yafei wang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China Key Research Institute of Yellow River Civilization and Sustainable Development Henan UniversityKaifeng475001China University of Chinese Academy of Sciences Beijing100049China

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission ***,because of limitations in historical data,quantitative estimations and spatially gridded reconstructions of these changes remain challenging,necessitating further methodological *** study focused on China's present-day land area over the past millennium,objectively capturing the characteristics and drivers of forest and grassland cover *** this basis,using the forest transition theory and the space-for-time substitution method,we depicted the historical deforestation process as an inverted“S”curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size ***,a gridded forest allocation model was established on the basis of deforestation *** the grassland cover,we implemented regionspecific methods,such as the cropland area deduction method and the habitat constraint method,to quantitatively reconstruct historical ***,we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland *** results indicated the following.(1)The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past *** feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2)The data indicated that China's forest area generally decreased over the past millennium,characterized by a“decrease-then-increase”*** forest area experienced three distinct phases:a slow decline(AD 1000–1650),a rapid decline(AD 16

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng wang Tao DUAN Kajie yang Bin yang Chunmei wang Xin TIAN Qi LU Institute of Ecological Conservation and Restoration Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China Institute of Desertification Institute of Desertification StudiesChinese Academy of ForestryBeijing100091China Institute of Great Green Wall Bayan Nur015200China Satellite Application Centre for Ecology and Environment MEEBeijing100094China Institute of Microelectronics Chinese Academy of SciencesBeijing100029China Aerospace Information Research Institute Chinese Academy of SciencesBeijing100094China Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution(VHR)unmanned aerial vehicle(UAV)and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover(FWVC)and fractional herbaceous vegetation cover(FHVC)in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error(RMSE)values for the FWVC and FHVC models were 10.69%and 11.67%,and the R^(2)values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10^(6)*** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy Land a

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Drone-YOLOv7: small target detection in UAV remote sensing images using YOLOv7-tiny with dynamic head

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Optoelectronics Letters 2025年

作者： yang Ye yang Sen tong Jigang wang Zenghui Tianjin University of Technology Department of Electrical Engineering， University of South Africa

In the task of detecting targets in unmanned aerial vehicles （UAVs） aerial images， the challenge arises from small size and wide scale span of targets， making their location， extraction and feature distinction difficult. Similar categories are susceptible to confusion. To address these issues， an improved YOLOv7-tiny aerial detection algorithm is proposed. Firstly， to improve the identification of small targets， a small target detection layer is added while removing the maximum target detection layer to enhance the localization ability of small targets and make the model lightweight. Secondly， a CBAM （Convolutional Block Attention Module） attention mechanism is incorporated at the connection between the backbone and neck to focus on the target area and eliminate interference. Additionally， to further enhance the classification and location capabilities of the targets， the detection head is replaced with a dynamic head （DYHead） with a unified channel number to fuse scale， space and task awareness in a single module. Finally， to overcome the difficulty of extracting features， the neck is replaced with a CS-FPN （Cross-Scale Feature Pyramid Network） structure with cross-scale connections to amplify feature fusion. Comparative experiments on the VisDrone2021 dataset show that the proposed model can improve mAP50and mAP0.5:0.95by 8.3% and 6.1%， respectively， compared to the original YOLOv7-tiny model， and significant improvements are also observed on CARPK and SeaDronesSee datasets.

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