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Autonomous Intelligent Systems 2021年第1期1卷 91-103页

作者： Panpan Zhou ben m.Chen Department of mechanical and Automation Engineering The Chinese University of Hong KongShatinN.T.Hong Kong

We study in this paper a semi-global leader-following output consensus problem for multiple heterogeneous linear systems in the presence of actuator position and rate saturation over a directed *** each follower,via the low gain feedback design technique and output regulation theory,both a state feedback consensus protocol and an output feedback consensus protocol are *** the output feedback case,different distributed observers are designed for the informed followers and uninformed followers to estimate the state of the leader and the follower *** show that the semi-global leader-following output consensus of heterogeneous linear systems can be achieved by the two consensus protocols if each follower is reachable from the leader in the directed communication topology.

关键词： multi-agent system Output consensus Low gain feedback

Staging the axilla in women with breast cancer: the utility of preoperative ultrasound-guided needle biopsy

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Cancer Biology & medicine 2014年第2期11卷 69-77页

作者： Nehmat Houssami robin m. Turner Screening and Test Evaluation Program (STEP) School of Public Health Sydney Medical School University of Sydney

Preoperative staging of the axilla in women with invasive breast cancer using ultrasound-guided needle biopsy(UNB) identifies approximately 50% of patients with axillary nodal metastases prior to surgical intervention. Although moderately sensitive, it is a highly specific staging strategy that is rarely falsely-positive, hence a positive UNB allows patients to be triaged to axillary lymph-node dissection(ALND) avoiding potentially unnecessary sentinel node biopsy(SNB). In this review, we extend our previous work through an updated literature search, focusing on studies that report data on UNB utility. Based on data for 10,934 breast cancer patients, sourced from 35 studies, a positive UNB allowed triage of 1,745 cases(simple proportion 16%) to axillary surgical treatment: the utility of UNB was a median 19.8% [interquartile range(IQR) 11.6%-26.7%] across these studies. We also modelled data from a subgroup of studies, and estimated that amongst patients with metastases to axillary nodes, the odds ratio(OR) for high nodal disease burden for a positive UNB versus a negative UNB was 4.38 [95% confidence interval(95% CI): 3.13, 6.13], Pm this model, the estimated proportion with high nodal disease burden was 58.9%(95% CI: 50.2%, 67.0%) for a positive UNB, whereas the estimated proportion with high nodal disease burden was 24.6%(95% CI: 17.7%, 33.2%) if UNB was negative. Overall, axillary UNB has good clinical utility and a positive UNB can effectively triage to ALND. However, the evolving landscape of axillary surgical treatment means that UNB will have relatively less utility where surgeons have modified their practice to omission of ALND for minimal nodal metastatic disease.

关键词： Breast cancer axillary staging node metastases test utility ultrasound-guided needle biopsy(UNB)

Physical activity and obese children

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Journal of Sport and Health Science 2012年第3期1卷 141-148,194页

作者： Alison m.mcmanus robin R.mellecker Institute of Human Performance University of Hong Kong

Childhood obesity is an epidemic of global proportions,accompanied by an alarming increase in various metabolic *** would appear that childhood obesity stems largely from excessive energy intake and that it is the ensuing obesity that leads to physical inactivity in children,as opposed to initial physical inactivity inducing *** changes in body composition that accompany obesity influence physical activity (PA) and the mechanistic basis for this remains poorly *** review provides an overview of the PA habits and body composition of the obese *** suggest skeletal muscle metabolism as a key driver of *** role both quantitative and qualitative changes in skeletal muscle may play in oxidative metabolism in the obese children are *** is a real need for research examining the mechanistic basis of physical inactivity in the *** dearth of information on the role of skeletal muscle metabolism in the PA of obese youngsters and the emergence of new technologies allowing cellular and metabolite mechanisms to be explored provides plenty of scope for future work.

关键词： Children Exercise Intervention Obesity Physical activity

Sex differences in cognition and their relationship to male mate choice

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Current Zoology 2019年第3期65卷 285-293页

作者： Jason KEAGY Ross mINTER robin m.TINGHITEELLA Department of Animal Biology School of Integrative Biology University of Illinois at Urbana-Champaign Urbana IL USA Linda Crnic Institute for Down Syndrome University of Colorado School of Medicine Aurora CO USA Department of Biological Sciences University of DenverDenverCOUSA

male cognition has gained recognition as an important potential player in sexual selection. A number of studies have found positive correlations between male sexual signals and cognitive performance an d/or female pref ere nces for males with better cog nitive performance, although other studies have not fou nd these relati on ships. Sex roles can differ dramatically, and sex differen ces in selection on cog nition likely follow from the different tasks associated with these sex roles. Here, using threespine stickleback Gasterosteus aculeatus, a species with clearly diverge nt sex roles and mutual mate choice, we focus on the cognitive trait inhibitory control because males must differentially respond to reproductive females versus other sticklebacks while defending territories and refrain from eating eggs and fry while performing paternal care. We presented fish with a detour task four times over a period of 7 days, allowing us to assess initial inhibitory control and improvement over time. We ask 1) whether there are sex differences in inhibitory control and 2) whether male mate choice is associated with female inhibitory control. Although males outperformed females on three different measures of detour task performance across four trials, these differences were largely explained by males being less neophobic than females. Females took more trials to successfully solve the detour task, even after accounting for sex differences in neophobia. Female cognitive abilities, however, were unrelated to the vigor with which males courted them. The equivocal results regarding sex differences in cognitive ability suggest further study given the very different selection pressures each sex experiences.

关键词： cognition detour task mutual mate choice sexual selection threespine stickleback

Small-area estimation of forest stand structure in Jalisco, mexico

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Journal of Forestry Research 2009年第4期20卷 285-292,I0004页

作者： robin m. Reich Celedonio Aguirre-Bravo Department of Forest Rangeland and Watershed Stewardship Colorado State University Fort Collins Rocky mountain Research Station USDA Forest Service Fort Collins

Natural resource statistics are often unavailable for small ecological or economic regions and policymakers have to rely on state-level datasets to evaluate the status of their resources （i.e., forests, rangelands, grasslands, agriculture, etc.） at the regional or local level. These resources can be evaluated using small-area estimation techniques. However, it is unknown which small area technique produces the most valid and precise results. The reliability and accuracy of two methods, synthetic and regression estimators, used in smallarea analyses, were examined in this study. The two small-area analysis methods were applied to data from Jalisco＇s state-wide natural resource inventory to examine how well each technique predicted selected characteristics of forest stand structure. The regression method produced the most valid and precise estimates of forest stand characteristics at multiple geographical scales. Therefore, state and local resource managers should utilize the regression method unless appropriate auxiliary information is not available.

关键词： forest structure regression estimator synthetic estimator spatial model stratified random sampling satellite imagery inventory and monitoring

Numerical Analysis of the Behavior of A New Aeronautical Alloy (Ti555-03) Under the Effect of A High-Speed Water Jet

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China Ocean Engineering 2019年第1期33卷 114-126页

作者： I.ben Belgacem L.Cheikh E.m.Barhoumi W.Khan W.ben Salem Laboratoire de Génie mécanique Ecole Nationale d’Ingénieurs de MonastirUniversité de Monastir Institut Préparatoire aux Etudes d’Ingénieur de monastir Université de Monastir Department of Electrical and Computer Engineering College of EngineeringDhofar University University of Waterloo Institut Supérieur des Arts et métiers de mahdia Université de Monastir

In this paper, we present a numerical simulation of a water jet impacting a new aeronautical material Ti555-03 *** Computational Fluid Dynamics(CFD) behavior of the jet is investigated using a FV(Finite Volume) *** Fluid–Structure Interaction(FSI) is studied using a coupled SPH(Smoothed Particle Hydrodynamics)-FE(Finite Element) method. The jets hit the metal sheet with an initial velocity 500 m/s. Two configurations which differ from each other by the position(angle of inclination) of the plate relatively to the axis of revolution of the jet inlet are investigated in this study. The objective of this study is to predict the impact of the fluid produced at high pressure and high speed especially at the first moment of impact. Numerical simulations are carried out under ABAQUS. We have shown in this study that the inclination of the titanium alloy plate by 45° stimulates the phenomenon of recirculation of water. This affects the velocity profile, turbulence and boundary layers in the impact zone. The stagnation zone and the phenomenon of water recirculation are strongly influenced by the slope of the plate which gives a pressure gradient and displacement very important between the two configurations. Fluctuations of physical variables(displacement and pressure) prove the need for a noise and vibratory study. These predictions will subsequently be used for the modeling of the problem of an orthogonal cut in a high-speed machining process assisted by high-pressure water jet.

关键词： Titanium alloy(Ti555-03) CFD turbulence ABAQUS Smoothed Particle Hydrodynamics(SPH) Fluid Structure Interaction(FSI)

EXISTENCE AND STABILITY RESULTS FOR GENERALIZED FRACTIONAL DIFFERENTIAL EQUATIONS

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Acta mathematica Scientia 2020年第1期40卷 141-154页

作者： A.ben mAKHLOUF D.BOUCENNA m.A.HAmmAmI Department of mathematics College of SciencesJouf UniversityAljoufSaudi Arabia Department of mathematics Faculty of Sciences of SfaxBP 11713000 SfaxTunisia Higher School for Professors of Technological Education SkikdaAlgeria

In this paper,a sufficient conditions to guarantee the existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1<α<2)are *** main results are obtained by using Kras... 详细信息

In this paper,a sufficient conditions to guarantee the existence and stability of solutions for generalized nonlinear fractional differential equations of orderα(1main results are obtained by using Krasnoselskii's fixed point theorem in a weighted Banach *** examples are given to demonstrate the validity of the proposed results.

关键词： nonlinear fractional differential equations stability analysis generalized fractional derivative Krasnoselskii's fixed point theorem

Photoelectrochemical activity of ZnO:Ag/rGO photo-anodes synthesized by two-steps sol-gel method

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Chinese Physics B 2022年第5期31卷 691-702页

作者： D ben Jemia m Karyaoui m A Wederni A Bardaoui m V martinez-Huerta m Amlouk R Chtourou Laboratory of Nanomaterials and Renewable Energy Systems LANSER Research and Technology Center of EnergyBorj-Cedria Science and Technology ParkBP 952050 Hammam-LifTunisia Faculty of Science of Tunis University of Tunis El ManarTunisia Laboratory of Physics of materials and Nanomaterials Applied to the Environment(LaPhymNE) Faculty of Sciences of GabesCite ErriadhUniversity of Gabes6079 GabesTunisia lnstitute of Catalysis and Petrochemistry CSICin MadridSpain Laboratory of Nanomaterials Nanotechnology and Energy(L2NE)University of Tunis El ManarTunisia

This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel *** physicochemical properties of the obtained photo-anodes were systematically studied by using several characterization *** x-ray diffraction analysis showed that all samples presented hexagonal wurtzite structure with a polycrystalline *** and energy dispersive x-ray(EDX)studies confirmed the existence of both Ag and r GO in Zn O:Ag/r GO thin *** estimated grain size obtained from scanning electron microscopy(SEm)analysis decreased with Ag doping,then increased to a maximum value after r GO *** UV-vis transmission spectra of the as-prepared Zn O:Ag and Zn O:Ag/r GO thin films have shown a reduction in the visible range with a redshift at the absorption *** bandgaps were estimated to be around 3.17 e V,2.7 e V,and 2.52 e V for Zn O,Zn O:Ag,and Zn O:Ag/r GO,***,the electrical measurements revealed that the charge exchange processes were enhanced at the Zn O:Ag/r GO/electrolyte interface,accompanied by an increase in the(PEC)performance compared to Zn O and Zn O:Ag ***,the photocurrent density of Zn O:Ag/r GO(0.2 m A·cm^(-2)) was around 4 and 2.22 times higher than photo-anodes based on undoped Zn O(0.05 m A·cm^(-2)) and Zn O:Ag(0.09 m A·cm^(-2)),***,from the flat band potential and donor density,deduced from the mott-Schottky,it was clear that all the samples were n-type semiconductors with the highest carrier density for the Zn O:Ag/r GO photo-anode.

关键词： zinc oxide reduced graphene oxide silver doping sol-gel photoelectrochemical performance

Host-environment mismatches associated with subalpine fir decline in Colorado

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Journal of Forestry Research 2016年第5期27卷 1177-1189页

作者： robin m. Reich John E. Lundquist Kristina Hughes Colorado State University Fort Collins CO USA U.S. Forest Service Anchorage Anchorage AK 99501 USA

Subalpine fir decline （SFD） has killed more trees in Colorado＇s high elevation forests than any other insect or disease problem. The widespread nature of this disorder suggests that the cause involves climatic factors. We examined the influence of varying combinations of average annual temperature and precipitation on the incidence and distribution of SFD. Climatic transition matrices generated in this study indicate that most healthy trees are found in climatic zones with moderate to low temperatures and high precipitation; whereas, SFD occurs mostly in zones of moderate temperatures and moderate precipitation. The contrasting distributions define an environmental mismatch. Forests matched with favorable climatic conditions thrive; those that are mismatched can become vulnerable to decline disease.

关键词： Abiotic disorder Climate stress High elevation forests Forest disease - Subalpine fir

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基于模糊控制的光子辐射制冷功率测量系统

光学学报 2024年第2期44卷 170-179页

作者：周玉晟朱虹雨陈犇陈嘉诚詹耀辉李孝峰苏州大学光电科学与工程学院江苏苏州215006 江苏省先进光学制造技术重点实验室教育部现代光学技术重点实验室江苏苏州215006

依据热平衡原理设计了以单片机为控制核心,DS18B20数字温度传感器和铂电阻PT100为检温元件,正温度系数(PTC)效应加热器为执行元件的温控及制冷功率测量系统。通过模糊PID(Proportional Integral Derivative)控制算法输出不同占空比的脉... 详细信息

依据热平衡原理设计了以单片机为控制核心,DS18B20数字温度传感器和铂电阻PT100为检温元件,正温度系数(PTC)效应加热器为执行元件的温控及制冷功率测量系统。通过模糊PID(Proportional Integral Derivative)控制算法输出不同占空比的脉宽调制波,控制辐射冷却材料温度和环境温度保持一致性,同时利用3D打印工艺完成装置的搭建,最终测算出辐射制冷功率。实验结果表明,系统测量计算的辐射制冷功率与理论预测值接近,该系统可以有效满足多种辐射冷却材料的测量。

关键词：测量辐射制冷制冷功率单片机温度调控模糊PID