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Stability of Periodic Orbits and Return Trajectories of Continuous Multi-valued Maps on Intervals

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Acta Mathematica Sinica,English Series 2018年第7期34卷 1121-1130页

作者： Tai Xiang SUN fan ping zeng Guang Wang SU Bin QIN Guangxi Key Laboratory Cultivation Base of Cross-border E-commerce Intelligent Information Processing Guangxi University of Finance and Economics

Let I be a compact interval of real axis R, and （L, H） be the metric space of all nonempty closed subintervals of I with the Hausdorff metric H and f ： I →L be a continuous multi-valued map. Assume that Pn = （x0, x1,..., xn） is a return trajectory of f and that p ∈ [min Pn, max Pn] with p ∈ f（p）. In this paper, we show that if there exist k （≥ 1） centripetal point pairs of f （relative to p） in {（xi;xi＋l）： 0 ≤ i ≤ n- 1} and n =sk＋r （0 ≤ r ≤ k - 1）, then f has an R-periodic orbit, where R=s＋1 ifsiseven, and R =s if s is odd and r = 0, and R=s＋2 if s is odd and r 〉0. Besides, we also study stability of periodic orbits of continuous multi-valued maps from I to L.

关键词： Continuous multi-valued map periodic orbit stability

Aggregation-regulated bioreduction process of graphene oxide by Shewanella bacteria

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Chinese Journal of Chemical Engineering 2024年第5期69卷 56-62页

作者： Kaixin Han Yibo zeng Yinghua Lu ping zeng Liang Shen Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China Chinese Research Academy of Environmental Sciences Beijing 100012China

The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction that involves instantaneous molecular *** bioreduction,the contact of bacterial cells and GO is considered the rate-limiting *** reveal how the bacteria-GO integration regulates rGO production,the comparative experiments of GO and three Shewanella strains were carried ***-transform infrared spectroscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,and atomic force microscopy were used to characterize the reduction degree and the aggregation *** results showed that a spontaneous aggregation of GO and Shewanella into the condensed entity occurred within 36 h.A positive linear correlation was established,linking three indexes of the aggregation potential,the bacterial reduction ability,and the reduction degree(ID/IG)comprehensively.

关键词： Graphene oxide Reduced graphene oxide Bioreduction Aggregation Shewanella

Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China

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Journal of Integrative Agriculture 2024年第5期23卷 1774-1785页

作者： Yan Zhang Yi Huang fan Zhang zeng Tang State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730020China

Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'*** pastoral China,formal financial institutions are gradually ***,a limited understanding remains of how formal credit affects herders'household *** on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive *** results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal *** credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth ***,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household ***,this study suggests that policies should improve herders'accessibility to formal credit.

关键词： formal credit herders expense Qinghai-Xizang Plateau

Development of a novel Eu^(3+)-doped tantalate red-emitting phosphor for w-LEDs application

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Journal of Rare Earths 2024年第8期42卷 1479-1488,I0003页

作者： fan zeng Jingjing Ru Bing Zhao Feiyun Guo Jianzhong Chen College of Chemistry and Materials Fujian Province University Key Laboratory of Green Energy and Environment CatalysisNingde Normal University.Ningde352100China School of Environment and Resources School of Carbon Neutral and Modern IndustryFujian Normal UniversityFuzhou350007China College of Information and Mechanical&Electrical Engineering Ningde Normal UniversityNingde352100China College of Chemistry Fuzhou UniversityFuzhou350108China

Two novel phosphors LiBa_(4(1-x))Eu_(4x)Ta_(3)O_(12)(H-LBTO:xEu^(3+)) and Li_(0.25)Ba_(1-x)Eu_(x)Ta_(0.75)O_(3)(C-LBTO:xEu^(3+))were prepared successfully by a molten salt *** transformation between these two structures was realized by changing the sintering temperature or changing the Eu^(3+) ions concentration,which was also demonstrated by the X-ray diffraction(XRD),scanning electron microscopy(SEM),diffuse reflectance spectra(DRS),and photoluminescence excitation(PLE) analyses,Both the sintering temperature and the Eu^(3+)ions doping concentration have significant impact on the formation of the crystal *** these phosphors sintered at 1023 K exhibit two major luminescence lines at 594 and 614 nm under nearUV light of 395 nm excitation,corresponding to Eu^(3+)ions typical transitions of ^(5)D_(0)→^(7)F_(1) and ^(5)D_(0)→^(7)F_(2).The optimum concentration of Eu^(3+) ions is 9 mol% for C-LBTO:xEu^(3+) samples and the quenching interaction type is the nearest-neighbor ion *** thermal stability of the C-LBTO:0.09Eu^(3+)sample was investigated in detail and the device application further suggests that C-LBTO:0.09Eu^(3+) can be used as a red phosphor for near-UV excited w-LEDs in lighting.

关键词： Phosphor Tantalate LED device Rare earths

Unsupervised Multi-Expert Learning Model for Underwater Image Enhancement

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 708-722页

作者： Hongmin Liu Qi Zhang Yufan Hu Hui zeng Bin fan the School of Intelligence Science and Technology and the Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China the School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China IEEE

Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded *** methods feed the whole image directly into the model for ***,they ignored that the R,G and B channels of underwater degraded images present varied degrees of degradation,due to the selective absorption for the *** address this issue,we propose an unsupervised multi-expert learning model by considering the enhancement of each color ***,an unsupervised architecture based on generative adversarial network is employed to alleviate the need for paired underwater *** on this,we design a generator,including a multi-expert encoder,a feature fusion module and a feature fusion-guided decoder,to generate the clear underwater ***,a multi-expert discriminator is proposed to verify the authenticity of the R,G and B channels,*** addition,content perceptual loss and edge loss are introduced into the loss function to further improve the content and details of the enhanced *** experiments on public datasets demonstrate that our method achieves more pleasing results in vision *** metrics(PSNR,SSIM,UIQM and UCIQE) evaluated on our enhanced images have been improved obviously.

关键词： Multi-expert learning underwater image enhancement unsupervised learning

A Study on the Performances of Solar Air Collectors Having a Hemispherical Dimple on the Absorber Plate

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Fluid Dynamics & Materials Processing 2024年第5期20卷 939-955页

作者： Shuilian Li fan zeng Xinli Wei School of Architecture and Environmental Engineering Zhengzhou Technical CollegeZhengzhou450121China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou450001China

In order to increase the efficiency of solar air collectors,a new variant with a protrusion is proposed in this study,and its performances are analyzed from two points of view,namely,in terms of optics and thermodynamics *** comparing and analyzing the light paths of the protrusion and the dimple,it can be concluded that when sunlight shines on the dimple,it is reflected and absorbed multiple times,whereas for the sunlight shining on the protrusion,there is no secondary reflection or absorption of *** the lighting area and the properties of the surfaces are the same,the absorption rate of the dimple is 10.3 percentage points higher than that of the *** the range of Reynolds number from 3000 to 11000,numerical simulations about the effects of the relative height(e/Dh=0.033–0.1)and relative spacing(p/e=4.5–8.5)of protrusions on air heat transfer and flow resistance show that,in terms of comprehensive evaluation coefficient(PF),the best relative height is 0.085,when the relative spacing is 5.A correlation of Nu and f with Re,e/Dh and p/e is obtained by linear regression of the results,in order to provide a useful reference for the design and optimization of this kind of solar air collector.

关键词： Heat transfer hemispherical protrusion dimple solar air collector correlation

Micropulse transscleral laser therapy for secondary angle-closure glaucoma in nanophthalmos: a case report

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1381-1384页

作者： ping Yu Bai-Yu Hu Yu He Lin Jing Han-Ying fan Jing Shu Liu-Zhi zeng Chengdu First People’s Hospital Chengdu 610095Sichuan ProvinceChina Eye School of Chengdu University of TCM Chengdu 610075Sichuan ProvinceChina

Dear Editor,The choice of surgical intervention for nanophthalmos patients with secondary angle-closure glaucoma poses a challenging decision for *** nanophthalmos patients who have undergone filtration surgery or other intraocular procedures are more susceptible to severe complications,including choroidal effusion,malignant glaucoma,and explosive choroidal hemorrhage,all of which can lead to vision loss[1].This dilemma is particularly pronounced in patients with shorter axial *** transscleral laser therapy(M-TLT),also known as micropulse transscleral cyclophotocoagulation(MP-TSCPC),is a nonincisional laser therapy surgery for glaucoma[2].In 2015,Golan and Kurtz[3]were the first to report four patients with secondary angle-closure glaucoma in nanophthalmos with axial lengths ranging between 17 and 19 mm(mean 18 mm)who were successfully treated with M-TLT,and choroidal detachment was observed in all patients(recovery spontaneously in two patients and recovery after systemic steroid treatment in the other two),of which two had a slight decrease in visual acuity.

关键词： glaucoma surgery closure

Social Radars: Finding Targets in Cyberspace for Cybersecurity

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 279-282页

作者： Lili fan Changxian zeng Yutong Wang Jiaqi Ma Fei-Yue Wang School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China School of Science Dalian Minzu UniversityDalian 116600China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90024 USA IEEE State Key Laboratory for Management and Control of Complex Systems Chinese Academy of SciencesBeijing 100190 Faculty of Innovation Engineering Macao University of Science and TechnologyMacao 999078China

INSPIRED by the insight from American political scientist Lasswell, who summarized the environmental role in societal surveillance [1], Schramm coined the term “social radar” [2] as it resembles the activities of radar in collecting and processing information, playing a crucial role in helping humans perceive changes in the internal and external environment and promptly adjusting adaptive behaviors.

关键词： prompt summarized insight

Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 160-175页

作者： Ya Liu Wenjuan Lu Dabao fan Weijian Tan Bo Hu Daxing zeng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Dongguan Engineering Technology Research Center for Parallel Robot Dongguan 523808China The DGUT Innovation Center of Robotics and Intelligent Equipment Dongguan 523808China

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the *** study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and ***,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were ***,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis ***,an HRCC kinematic model was established to verify the self-alignment capability of the *** this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

关键词： Ankle rehabilitation robot Self-alignment Parallel mechanism Type synthesis Screw theory