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Generalized gradient projection neural networks for nonsmooth optimization problems

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Science china(Information Sciences) 2010年第5期53卷 990-1005页

作者： LI GuoCheng 1 , SONG ShiJi 2.? & wu Cheng 2.1 Department of Mathematics, beijing Information Science and Technology {2., beijing 100192. china 2.Department of Automation, tsinghua university, beijing 100084, china 1. Department of Mathematics Beijing Information Science and Technology University Beijing 100192 China2. Department of Automation Tsinghua University Beijing 100084 China

Generalized gradient projection neural network models are proposed to solve nonsmooth convex and nonconvex nonlinear programming problems over a closed convex subset of R n . By using Clarke’s generalized gradient, the neural network modeled by a differential inclusion is developed, and its dynamical behavior and optimization capabilities both for convex and nonconvex problems are rigorously analyzed in the framework of nonsmooth analysis and the differential inclusion theory. First for nonconvex optimization problems, the quasi convergence results similar to those achieved by previous work are proved. For convex optimization problems, the global convergence results are proved, i.e. any trajectory of the neural network converges to an asymptotically stable equilibrium point, which is an optimal solution of the primal problem whenever it exists. This result remains valid even if the initial condition is chosen outside the feasible set. In addition, an asymptotic control result involving a Tykhonov like regularization shows that any trajectory of the revised neural network can be forced to converge toward a particular optimal solution of the primal problem. Finally, two simulation optimization algorithms for solving the optimization and control problems are designed respectively, and three typical simulation experiments are illustrated to present the accuracy and efficiency of theoretical convergence results of this paper.

关键词： nonsmooth optimization problem generalized gradient projection networks differential inclu sions convergence

Utility of Goal Attainment Scaling(GAS)in evaluating a multicomponent exercise programme for community-dwelling pre-frail older adults

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Family Medicine and Community Health 2024年第1期12卷 36-44页

作者： Juan Fang jianping ren Jinjing Wang Xiantao Qiu Shiyan Zhang Shuang Yuan Liangfeng {2. Lin Xie Le Yu School of Public Health Hangzhou Normal UniversityHangzhouZhejiangChina School of Medicine Huzhou UniversityHuzhouZhejiangChina School of Clinical Medicine Hangzhou Normal UniversityHangzhouZhejiangChina Ziyang Street Community Health Service Center HangzhouZhejiangChina

Objectives This study aimed to investigate the effectiveness of Goal Attainment Scaling(GAS)in assessing an intervention for pre-frail senior ***,the study aimed to explain how the GAS goals were established based on the International Classification of Functioning,Disability and Health(ICF)categories,including body function,activity and participation and environmental *** In this study,2.0 pre-frail older adults were randomly selected to participate in a controlled *** intervention group engaged in multicomponent exercise three times a week,once at a community health service location and twice at *** control group received advice on physical activity but did not have supervised *** in both groups selected individualised GAS goals from 2. goals developed based on ICF by focus group *** study used generalised estimating equations to analyse the differences between the *** The study included 144 participants,72.in the exercise group and 72.in the control *** top three individualised goals for all participants were vestibular functions(53.5%),pain management(43.1%)and lifting and carrying objects(31.9%).Both groups saw a significant increase in GAS scores at week 8 and week 2. of the intervention(p<0.05),but the exercise group showed a more significant improvement(p<0.05).The participants living alone were associated with lower postintervention improvements in the GAS *** contrast,the participants who were using a smartphone were likely to get higher postintervention improvements in the GAS *** GAS can be a valuable tool for setting and evaluating individualised and meaningful goals in body functions,activity and participation and environmental *** multicomponent exercise interventions can help pre-frail older adults achieve their expected goals as measured by the GAS.

关键词： meaningful goals lifting

A New Species of the Genus Scincella Mittleman,1950(Squamata:Scincidae)from Sichuan Province,Southwest china

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Asian Herpetological Research 2024年第2期15卷 115-129页

作者： Ruwan JIA Zongyuan GAO Dihao wu Jinlong ren Dechun JIANG Wei wu CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610213SichuanChina university of Chinese Academy of Sciences Beijing 100049China

The genus Scincella Mittleman,1950,within the family Scincidae,is a diverse group comprising 39 described *** taxonomy of the genus is complex due to morphological similarities among species,which often obscures the true extent of biodiversity,resulting in several undescribed species requiring further *** china,particularly within the unique ecosystems of the Hengduan Mountains,the diversity of Scincella is notably underestimated,with only 12.species currently *** the present study,we describe a new species of the genus Scincella,Scincella liangshanensis ***.,from Sichuan Province,Southwest *** characteristics and phylogenetic analyses revealed that the putative new species is distinct from all other known *** discovery not only expands the known diversity of Scincella but also emphasizes the inadequacies in our current understanding of herpetological diversity in *** addition of this species to the scientific record highlights the necessity for ongoing biodiversity assessments to uncover hidden species and enhance our understanding of the intricate web of life in one of the world’s biodiversity hotspots.

关键词： morphology phylogeny Scincella liangshanensis sp.nov. taxonomy the Hengduan Mountains

Research on dual-stator winding multi-phase high-speed induction generator with rectifier load

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Science china(Technological Sciences) 2008年第6期51卷 683-692页

作者： WANG XiangHeng1 & wu XinZhen2.1 Department of Electrical Engineering, tsinghua university, {2., {2. 2.Department of Electrical Engineering, Qingdao university, Qingdao 2.6071, {2. 1. Department of Electrical Engineering Tsinghua University Beijing 100084 China 2. Department of Electrical Engineering Qingdao University Qingdao 266071 China

Based on analysis and calculation of the relation between current harmonics and MMF harmonics in the dual-stator winding multi-phase high-speed induction gen-erator with a rectifier load, a new idea, which divides the generator system into two sub-systems to be analyzed individually, is presented. For the sub-system of the 12.phase power winding with a rectifier load, the loop current method is used to establish network equation set in terms of the network graph theory. The numerical stability problem is solved by alternating use of fixed time-step and varied time-step, and the voltage and current with their fundamental components of the power winding are obtained. For the other sub-system of the induction generator with dual-stator winding and solid cage rotor, the electromagnetic field analysis method and the multi-variable optimization approach are combined to get the con-trol winding current and stator frequency. Calculated results well match experiment results, indicating that the new proposed method is of effectiveness and high ac-curacy.

关键词： dual-stator winding induction generator rectifier load MMF analysis loop current method finite element method optimization approach

Advances in seismological methods for characterizing fault zone structure

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Earthquake Science 2024年第2期37卷 122-138页

作者： Yan Cai jianping wu Yaning Liu Shijie Gao Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China

Large earthquakes frequently occur along complex fault *** seismic rupture and long-term fault evolution requires constraining the geometric and material properties of fault zone *** provide a comprehensive overview of recent advancements in seismological methods used to study fault zone structures,including seismic tomography,fault zone seismic wave analysis,and seismicity *** conditions limit our current ability to fully characterize fault zones,for example,insufficient imaging resolution to discern small-scale anomalies,incomplete capture of crucial fault zone seismic waves,and limited precision in event location *** seismic arrays can overcome these limitations and enable more detailed investigations of fault zone ***,we present new insights into the structure of the Anninghe-Xiaojiang fault zone in the southeastern margin of the Qinghai-Xizang Plateau based on data collected from a dense seismic *** found that utilizing a dense seismic array can identify small-scale features within fault zones,aiding in the interpretation of fault zone geometry and material properties.

关键词： fault zone structure tomography fault zone wave seismic activity Anninghe-Xiaojiang fault zone

Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review

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Food Science and Human Wellness 2024年第3期13卷 1135-1151页

作者： Enning Zhou Qiangqiang Li Dan Zhu gang Chen Liming wu Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Department of Food Science University of OtagoDunedin 9016New Zealand School of Food and Health Beijing Technology and Business UniversityBeijing 100048China

Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding *** the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce *** here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic *** techniques for characterizing changes in these properties of food allergens are *** processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new ***,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food *** provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.

关键词： Food allergens Protein structural characterization Immunogenicity evaluation Food processing modification

Three dimensional velocity model and its tectonic implications at china Seismic Experimental Site,eastern margin of the Tibetan Plateau

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Science china Earth Sciences 2024年第7期67卷 2268-2290页

作者： jianping wu Yan CAI Wei WANG Weilai WANG Changzai WANG Lihua FANG Yaning LIU Jing LIU Institute of Geophysics China Earthquake AdministrationBeijing 100081China beijing Baijiatuan Earth Science National Observation and Research Station Beijing 1095China beijing Earthquake Agency Beijing 100080China

The china Seismic Experimental Site(CSES)is located at the intersection of the Tibetan Plateau,South china Block,and Indian Plate and has complex geological settings and intense crustal deformation,making it one of the most seismically active areas in Chinese mainland.A high-resolution,three-dimensional(3D)crust-mantle velocity structure is crucial for understanding seismotectonic environments,lithospheric deformation mechanisms,and deep dynamic *** first constructed a high-vertical-resolution 3D initial velocity model using the joint inversion of receiver functions and surface waves and then obtained a 3D P-and S-wave velocity model(CSES-VM1.0)with the highest lateral resolution of 0.2.°for the CSES using double-diffe{2.ce *** to the limitations of the Sn observation data,the resolution of the S-wave velocity model in the lower crust and upper mantle was reduced,making it closer to the initial model provided by joint inversion.A comparison with explosive-source seismic data showed that the synthetic P-wave first-arrival travel times of the new model were closer to the observations than those of the previous velocity *** velocity cross-sections across the source areas of the 2.2. Lushan MS6.1 and Ludian MS6.8 earthquakes reveal that the former earthquake occurred near a weak contact zone between the Tibetan Plateau and Sichuan Basin,and the rupture of the latter earthquake occurred in a granitic area,with the northern end blocked by rigid high-velocity bodies.A clear high-velocity anomaly zone is distributed along the western margin of the Yangtze Block,revealing the spatial distribution of Neoproterozoic intermediate-basic *** high-velocity zone significantly controls the morphology of fault zones and influences the rupture processes of major *** northeast-southwest and north-south t{2.ding high-velocity anomalies were found near Panzhihua,potentially related to Neoproterozoic and Middle-Late Permian intermediate

关键词： Eastern Tibetan Plateau china Seismic Experimental Site Yangtze Block Velocity model Double-difference tomography

Experimental study on bed-load sediment transport under irregular wave and current combined flow

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Acta Oceanologica Sinica 2001年第2期20卷 271-280页

作者： wu Yongsheng,Qin Chongren (1. Department of Hydraulic Engineering, {2., beijing 100084, {2. 2. School of Civil Engineering, Tianjin university, Tianjin 300072. {2.) Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Using an irregularly oscillating tray and flume, a series of experiments are completed to evaluate bed-load sediment transport rate under irregular wave -current coexistent field. Testing conditions include three interaction angles 0', 45', 90' and two kinds of median sizes (0.38 and 1.10 mm). The results of transport rate show that the net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress of waves, mean shear stress of current and the grain size.

关键词： Irregular wave-current bed-load transport rate

Effect of the sloping seabed on 3D soil-spudcan interaction using a material point-finite element(MPM-FEM)model

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1436-1454页

作者： Zhengda Lei Guangtian Zeng Huaihui ren Bisheng wu Yuxin Jie State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijingChina Key Laboratory of the Hydrosphere Sciences of the Ministry of Water Resources BeijingChina Institute of Ocean Engineering Tsinghua UniversityBeijingChina Longyuan (beijing) Wind Power Engineering Technology Co. Ltd.BeijingChina

The sloping seabed affects the bearing capacity and failure mechanism of soil,which may compromise the stability and safety of offshore structures such as jack-up *** paper employs a coupled model combining the material point method and finite element method(MPM-FEM)to analyze the impact of sloping seabeds on the three-dimensional soil-spudcan *** MPM-FEM model implements the B¯approach to solve the challenge of volumetric locking due to the incompressibility constraints imposed by yield *** is validated against the centrifuge *** effects of sloping seabeds on penetration resistance,soil flow pattern,lateral response,stress distribution,and failure mechanism are *** soil mainly undergoes overall failure when the ratio of penetration depth to spudcan diameter(i.e.D P/D)is between 0 and *** the slope angle increases,the soil on the side of lower slope is expelled further,resulting in an asymmetric stress distribution and a larger horizontal sliding force of *** D P/D increases to 0.75,the soil transitions to localized plastic flow failure,and the range of soil flow affected by the spudcan penetration *** results show that,when the slope angle increases,the lateral displacement and stress distribution on the lower slope of a sloping seabed is significantly larger than that of a horizontal seabed,impacting the spudcan and surrounding soil *** study suggests that the seabed slope significantly affects the range of soil flow and failure at shallow penetration,indicating that the slope angle should be taken into account in the design and installation of offshore jack-up rigs,particularly in areas with sloping seabeds.

关键词： Soil-spudcan interaction Centrifuge tests MPM-FEM model B—approach Sloping seabeds Offshore structures