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Multi-LeapMotion sensor based demonstration for robotic refine tabletop object manipulation task

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CAAI Transactions on Intelligence Technology 2016年第1期1卷 104-113页

作者： haiyang jin Qing Chen Zhixian Chen Ying Hu Jianwei Zhang Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen China Chinese University ofHong Kong Hong Kong China University of Hamburg Hamburg Germany

In some complicated tabletop object manipulation task for robotic system, demonstration based control is an efficient way to enhance the stability of execution. In this paper, we use a new optical hand tracking sensor, LeapMotion, to perform a non-contact demonstration for robotic systems. A Multi-LeapMotion hand tracking system is developed. The setup of the two sensors is analyzed to gain a optimal way for efficiently use the informations from the two sensors. Meanwhile, the coordinate systems of the Mult-LeapMotion hand tracking device and the robotic demonstration system are developed. With the recognition to the element actions and the delay calibration, the fusion principles are developed to get the improved and corrected gesture recognition. The gesture recognition and scenario experiments are carried out, and indicate the improvement of the proposed Multi-LeapMotion hand tracking system in tabletop object manipulation task for robotic demonstration.

关键词： LeapMotion sensor Muti-sensor fusion Tele-operative demonstration Gesture recognition Tabletop object manipulation

Beamforming design for covert broadcast communication with hidden adversary

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Science China(Information Sciences) 2024年第6期67卷 384-398页

作者： Weiyu CHEN haiyang DING Shilian WANG Junshan LUO Fengkui GONG College of Electronic Science and Technology National University of Defense Technology College of Information and Communication National University of Defense Technology State Key Laboratory of Integrated Service Networks Xidian University

This paper explores covert broadcast communication in a challenging situation in which the transmitter, Alice, faces uncertainty regarding the position of the passive adversary, Willie. In this situation,controlling the signal exposure becomes difficult. Specifically, this paper focuses on the cases where Alice can delimit the suspicious areas where Willie may be located. The suspicious areas can have arbitrary number and shapes. Under the Rician fading model, the analytical expression of Willie's detection performance is derived. Then, the transmit power, the beamforming direction, and the number of channel uses are jointly designed to minimize the optimal Willie's detection performance among all the possible positions of Willie, on the premise of satisfying receivers' quality-of-service requirements. To tackle the formulated knotty problem with an infinite number of irregular and discontinuous Willie's possible positions, the continuous nature of the antenna pattern is exploited to convert the original problem into the one with a finite number of possible positions, by sampling the suspicious areas. Then, different algorithms are developed to address the resultant non-convex optimization problem for single-antenna Willie and multi-antenna Willie, respectively. Numerical results demonstrate significant performance gains of the proposed scheme over the widely-adopted maximum ratio transmission scheme, which indicates that simply adjusting the main lobe towards the receiver is indeed far away from optimum and shows the importance of leveraging Alice's limited knowledge of Willie's position.

关键词： low-probability-of-detection communication multiple antennas covertness performance uncertain position parameters optimization

Effect mechanism of seepage force on the hydraulic fracture propagation

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International Journal of Coal Science & Technology 2024年第3期11卷 223-240页

作者： haiyang Wang Desheng Zhou Yi Zou Peng Zheng School of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065China Engineering Research Center of Development and Management for Low to Extra-Low Permeability Oil and Gas Reservoirs in West China Ministry of EducationXi’an Shiyou UniversityXi’an710065ShaanxiChina Xi’an University of Science and Technology Xi’an710054ShaanxiChina

The flow of fluid through the porous matrix of a reservoir rock applies a seepage force to the solid rock *** the seepage force exerted by fluid flow through the porous matrix of a reservoir rock has a notable influence on rock deformation and failure,its effect on hydraulic fracture(HF)propagation remains ***,in this study,we improved a traditional fluid–solid coupling method by incorporating the role of seepage force during the fracturing fluid seepage,using the discrete element ***,we validated the simulation results of the improved method by comparing them with an analytical solution of the seepage force and published experimental ***,we conducted numerical simulations in both homogeneous and heterogeneous sandstone formations to investigate the influence of seepage force on HF *** results indicate that fluid viscosity has a greater impact on the magnitude and extent of seepage force compared to injection rate,and that lower viscosity and injection rate correspond to shorter hydraulic fracture ***,seepage force influences the direction of HF propagation,causing HFs to deflect towards the side of the reservoir with weaker cementation and higher permeability.

关键词： Hydraulic fracturing Seepage force Fracture propagation Discrete element method Reservoir heterogeneity

Stability analysis of a liquid crystal elastomer self-oscillator under a linear temperature field

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 337-354页

作者： haiyang WU Jiangfeng LOU Biao ZHANG Yuntong DAI Kai LI School of Civil Engineering Anhui Jianzhu UniversityHefei 230601China

Self-oscillating systems abound in the natural world and offer substantial potential for applications in controllers,micro-motors,medical equipments,and so ***,numerical methods have been widely utilized for obtaining the characteristics of self-oscillation including amplitude and ***,numerical methods are burdened by intricate computations and limited precision,hindering comprehensive investigations into self-oscillating *** this paper,the stability of a liquid crystal elastomer fiber self-oscillating system under a linear temperature field is studied,and analytical solutions for the amplitude and frequency are ***,we establish the governing equations of self-oscillation,elucidate two motion regimes,and reveal the underlying ***,we conduct a stability analysis and employ a multi-scale method to obtain the analytical solutions for the amplitude and *** results show agreement between the multi-scale and numerical *** research contributes to the examination of diverse self-oscillating systems and advances the theoretical analysis of self-oscillating systems rooted in active materials.

关键词： self-oscillation stability analysis multi-scale method liquid crystal elastomer linear temperature field

施氮对郑麦366光合速率、花后干物质积累及产量的影响

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作物杂志 2024年第3期 127-132页

作者：张素瑜岳俊芹李向东靳海洋任德超杨明达邵运辉王汉芳方保停张德奇时艳华秦峰程红建河南省农业科学院小麦研究所/农业农村部中原地区作物栽培科学观测实验站/河南省小麦产量―品质协同提升工程研究中心河南郑州450002 商丘市农林科学院河南商丘476000

通过2年大田试验,分析不同施氮措施对郑麦366花后旗叶相对叶绿素含量(SPAD)、光合速率、花后干物质积累及产量的影响,探究最佳施氮量和施氮方式。设置4个施氮处理,分别为不施氮(N_(0))、基施纯氮210 kg/hm^(2)(N_(210))、基施纯氮150 kg... 详细信息

通过2年大田试验,分析不同施氮措施对郑麦366花后旗叶相对叶绿素含量(SPAD)、光合速率、花后干物质积累及产量的影响,探究最佳施氮量和施氮方式。设置4个施氮处理,分别为不施氮(N_(0))、基施纯氮210 kg/hm^(2)(N_(210))、基施纯氮150 kg/hm^(2)+拔节期追施纯氮60 kg/hm^(2)(N_(150+60))、基施纯氮150 kg/hm^(2)+拔节期追施纯氮120 kg/hm^(2)(N_(150+120))。结果表明,与其他氮肥处理相比,2018-2019、2019-2020年度N_(0)处理下灌浆期旗叶净光合速率、灌浆后期旗叶SPAD、花后干物质积累对籽粒产量的贡献率、千粒重和产量均显著降低。与N_(210)处理相比,N_(150+60)处理2018-2019年度灌浆末期小麦旗叶SPAD、花后干物质积累对籽粒产量的贡献率、千粒重及产量分别提高12.9%、9.7%、6.5%、1.6%,2019-2020年度分别提高16.3%、27.2%、6.3%、10.0%。与N_(150+120)处理相比,N_(150+60)处理显著降低2018-2019年度灌浆末期冬小麦的旗叶SPAD、灌浆期旗叶净光合速率,但2019-2020年度差异不显著,N_(150+60)处理显著提高2018-2019年度冬小麦的穗粒数、产量及2年的氮肥偏生产力。综合考虑小麦净光合效率、产量及氮肥生产效率,N_(150+60)处理是更适宜豫北平原的施氮方式。

关键词：小麦氮肥光合速率产量氮肥偏生产力

Breeding maize of ideal plant architecture for high-density planting tolerance through modulating shade avoidance response and beyond

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Journal of Integrative Plant Biology 2024年第5期66卷 849-864页

作者： Fereshteh Jafari Baobao Wang haiyang Wang Junjie Zou Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Graduate School of Chinese Academy of Agricultural Sciences Beijing 100081China National Nanfan Research Institute CAASSanya 572025China State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of Life SciencesSouth China AgriculturalUniversityGuangzhou 510642China

Maize is a major staple crop widely used as food,animal feed,and raw materials in industrial ***-density planting is a major factor contributing to the continuous increase of maize ***,high planting density usually triggers a shade avoidance response and causes increased plant height and ear height,resulting in lodging and yield *** plant height and ear height,more erect leaf angle,reduced tassel branch number,earlier flowering,and strong root system architecture are five key morphological traits required for maize adaption to high-density *** this review,we summarize recent advances in deciphering the genetic and molecular mechanisms of maize involved in response to high-density *** also discuss some strategies for breeding advanced maize cultivars with superior performance under high-density planting conditions.

关键词： flowering time high-density planting leaf angle maize plant architecture plant height/ear height root architecture tasselbranch

A Highly Efficient Ni/Al_(2)O_(3)-LaO_(x) Catalyst for the Reductive Amination of Furfural to Furfurylamine:the Promoting Effect of La

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Chemical Research in Chinese Universities 2024年第1期40卷 36-46页

作者： YANG Yinze ZHANG Liyan ZHOU Leilei CHENG haiyang ZHAO Fengyu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science Technology of ChinaHefei 230026P.R.China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

The reductive amination of furfural to furfurylamine is an important and still challenging topic in the field of biomass conversion. In this work, we prepared a series of Ni/Al_(2)O_(3)-LaO_(x) catalysts by co-precipitation method, the role of La played in promoting the catalytic performances of reductive amination furfural was discussed based on the changes in the electronic state of Ni species, acidity, and Ni particle size. The catalytic activity and the selectivity of furfurylamine are highly dependent on the surface properties and the structure of the catalyst. The addition of La promoted the amount of strong acidic sites and the H2dissociation and spillover on the surface, thus inducing the improvement of the catalytic activity and furfurylamine selectivity. The Ni/Al_(2)O_(3)-0.5LaO_(x)catalyst with suitable acid sites gave a high yield of furfurylamine (94.9%) under mild reaction conditions. Moreover, the catalyst could be recycled five times without significant loss in activity. The Ni/Al_(2)O_(3)-LaO_(x) catalyst is of great promise in the production of amines via reductive amination reaction.

关键词： Reductive amination Furfural Nickel catalyst Furfurylamine Lanthanum

Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang Li Ying Zhang haiyang He Yu Wu Danyu Wu Zhenhao Guan Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex Non-Ferrous Metal Resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)*** suitability of LUT as a calcite depressant is confirmed through micro-flotation *** pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two ***,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on *** capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is ***-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions *** directly illustrates the distinct adsorption densities of LUT on the two miner-al ***,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

Enhanced charge collection of AgNWs-based top electrode to realize high-performance,all-solution processed organic solar cells

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Science China Chemistry 2024年第10期67卷 3347-3356页

作者： Juanyong Wan Yang Chen Weijie Chen jinfeng Xia Guang Zeng Jianlei Cao Chuang jin Yunxiu Shen Xiaoxiao Wu haiyang Chen Junyuan Ding Xue-mei Ou Yaowen Li Yongfang Li Laboratory of Advanced Optoelectronic Materials Suzhou Key Laboratory of Novel Semiconductor-Optoelectronics Materials and DevicesCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China Jiangsu Sidike New Materials Science and Technology Co. Ltd.Suqian 215400China

All-solution processed organic solar cells are the ultimate aim of printable photovoltaics,but their electrical losses arising from poor contact of top electrodes greatly limit efficiency *** solve the problem,a solution-processed hybrid top electrode was constructed using silver nanowires(AgNWs)as the skeleton and ZnO nanoparticles(ZnO-NPs)as the *** constructing the skeleton,a spin-rinsing treatment was first used to reduce the amount of the residual insulating polyvinylpyrrolidone wrapped around the AgNWs to promote intimate contact among the AgNWs in the ***,the ZnO-NPs matrix was deposited onto the AgNWs skeleton,bridging the AgNWs skeleton with the underlayer ZnO-NPs electron transporting layer(ETL).The underlayer ZnO-NPs ETL can also induce the growth of the ZnO-NPs matrix to minimize lattice mismatch,which creates additional transport channels from the ETL to the AgNWs skeleton for charge *** a result,the obtained electrode significantly enhances the electrical contact in the device,thus delivering record power conversion efficiencies of 16.04%and 14.54%for rigid and flexible all-solution processed OSCs,respectively.

关键词： solution-processed top electrode organic solar cells AgNWs electrical contact