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Large-field objective lens for multi-wavelength microscopy at mesoscale and submicron resolution 被引量:2
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作者 Xin Xu Qin Luo +7 位作者 Jixiang Wang Yahui Song Hong Ye Xin Zhang Yi He Minxuan Sun Ruobing Zhang Guohua Shi 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第6期41-56,共16页
Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 mm.This restriction poses a challenge when attempting to simultaneously anal... Conventional microscopes designed for submicron resolution in biological research are hindered by a limited field of view,typically around 1 mm.This restriction poses a challenge when attempting to simultaneously analyze various parts of a sample,such as different brain areas.In addition,conventional objective lenses struggle to perform consistently across the required range of wavelengths for brain imaging in vivo.Here we present a novel mesoscopic objective lens with an impressive field of view of 8 mm,a numerical aperture of 0.5,and a working wavelength range from 400 to 1000 nm.We achieved a resolution of 0.74μm in fluorescent beads imaging.The versatility of this lens was further demonstrated through high-quality images of mouse brain and kidney sections in a wide-field imaging system,a confocal laser scanning system,and a two-photon imaging system.This mesoscopic objective lens holds immense promise for advancing multi-wavelength imaging of large fields of view at high resolution. 展开更多
关键词 mesoscopic objective lens large field-of-view high resolution MULTI-WAVELENGTH wide-field microscopy confocal laser scanning microscopy
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Hierarchical Algorithms of Large-Scale Systems with Nonseparable Multiobjective
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作者 解三名 吴沧浦 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期79+73-79,共8页
A class of large-scale hierarchical control systems is considered, the overall objective function is a nonlinear and nonseparable function of multiple quadratic performance indices.The separation strategy of the multi... A class of large-scale hierarchical control systems is considered, the overall objective function is a nonlinear and nonseparable function of multiple quadratic performance indices.The separation strategy of the multiobjective optimization technique and the three-level objective coordination method are applied to the large -sacle systems, and a four-level hierarchical algorithms of optimization control is obtained. 展开更多
关键词 hierarchical system/objective coordination multiobjective optimization
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基于Stingray Objective Studio的防空C^3I显控系统界面开发
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作者 狄博 李进 雷英杰 《弹箭与制导学报》 CSCD 北大核心 2005年第SA期456-457,466,共3页
文中提出了用 Stingray Objective Studio 工具集来进行防空显控系统界面开发,使得开发人员将大量的时间和精力用于系统结构和数据处理算法上,这样不光降低了开发难度,也增强了系统的功能和稳定性。
关键词 STINGRAY objective STUDIO 防空 C^3I 显控系统
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China English——An Objective Existence as a Performance Variety
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作者 黄春燕 《语言与文化研究》 2008年第1期187-192,共6页
China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the ph... China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the phonology,vocabulary,syntax,rhetoric and text,particularly in the vocabulary.This essay will discuss the features of China English from the following three aspects: the development of English in China;the comparison between China English,Pidgin English and Chinese English and the Chinese words borrowed by English. 展开更多
关键词 China ENGLISH objective EXISTENCE PERFORMANCE VARI
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Multi-objective route planning approach for timely searching tasks of a supervised robot
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作者 刘鹏 熊光明 +2 位作者 李勇 姜岩 龚建伟 《Journal of Beijing Institute of Technology》 EI CAS 2014年第4期481-489,共9页
To performance efficient searching for an operator-supervised mobile robot, a multiple objectives route planning approach is proposed considering timeliness and path cost. An improved fitness function for route planni... To performance efficient searching for an operator-supervised mobile robot, a multiple objectives route planning approach is proposed considering timeliness and path cost. An improved fitness function for route planning is proposed based on the multi-objective genetic algorithm (MOGA) for multiple objectives traveling salesman problem (MOTSP). Then, the path between two route nodes is generated based on the heuristic path planning method A *. A simplified timeliness function for route nodes is proposed to represent the timeliness of each node. Based on the proposed timeliness function, experiments are conducted using the proposed two-stage planning method. The experimental results show that the proposed MOGA with improved fitness function can perform the searching function well when the timeliness of the searching task needs to be taken into consideration. 展开更多
关键词 multiple objective optimization multi-objective genetic algorithm supervised robots route planning TIMELINESS
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OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:4
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作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi — objects genetic algorithm problem on optimizing result, this method is analyzed theoretically and discussed by using an autonomous underwater vehicle (AUV) as... To research the effect of the selection method of multi — objects genetic algorithm problem on optimizing result, this method is analyzed theoretically and discussed by using an autonomous underwater vehicle (AUV) as an object. A changing weight value method is put forward and a selection formula is modified. Some experiments were implemented on an AUV, TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi objective optimization genetic algorithm selection method
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Well production optimization using streamline features-based objective function and Bayesian adaptive direct search algorithm 被引量:2
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作者 Qi-Hong Feng Shan-Shan Li +2 位作者 Xian-Min Zhang Xiao-Fei Gao Ji-Hui Ni 《Petroleum Science》 SCIE CAS CSCD 2022年第6期2879-2894,共16页
Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.T... Well production optimization is a complex and time-consuming task in the oilfield development.The combination of reservoir numerical simulator with optimization algorithms is usually used to optimize well production.This method spends most of computing time in objective function evaluation by reservoir numerical simulator which limits its optimization efficiency.To improve optimization efficiency,a well production optimization method using streamline features-based objective function and Bayesian adaptive direct search optimization(BADS)algorithm is established.This new objective function,which represents the water flooding potential,is extracted from streamline features.It only needs to call the streamline simulator to run one time step,instead of calling the simulator to calculate the target value at the end of development,which greatly reduces the running time of the simulator.Then the well production optimization model is established and solved by the BADS algorithm.The feasibility of the new objective function and the efficiency of this optimization method are verified by three examples.Results demonstrate that the new objective function is positively correlated with the cumulative oil production.And the BADS algorithm is superior to other common algorithms in convergence speed,solution stability and optimization accuracy.Besides,this method can significantly accelerate the speed of well production optimization process compared with the objective function calculated by other conventional methods.It can provide a more effective basis for determining the optimal well production for actual oilfield development. 展开更多
关键词 Well production Optimization efficiency Streamline simulation Streamline feature objective function Bayesian adaptive direct search algorithm
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Objective identification research on cold vortex and mid-summer rainy periods in Northeast China 被引量:1
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作者 龚志强 封泰晨 房一禾 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期571-580,共10页
Considering the differences between the Northeast China Cold Vortex (CV) and the Mid-Summer (MS) rainy period and their corresponding atmospheric circulations are comprehensively analyzed, and the objective identi... Considering the differences between the Northeast China Cold Vortex (CV) and the Mid-Summer (MS) rainy period and their corresponding atmospheric circulations are comprehensively analyzed, and the objective identification methods of defining the annual beginning and ending dates of Northeast China CV and MS rainy periods are developed respectively. The annual beginning date of the CV (MS) rainy period is as follows. In a period from April to August, if daily regional mean precipitation ryi is larger than yearly regional mean precipitation R (or 2R) on a certain day, the station precipitation rs is larger than the station yearly mean precipitation (r/ (or 2(r)) in at least 50% of stations in Northeast China, and this condition is satisfied in the following 2 (7) days, then this date is defined as the beginning date of the CV (MS) rainy period. While the definition of the ending date of the MS rainy period shows the opposite process to its beginning date. With this objective identification method, the multi-year average (1981-2010) beginning date of the CV rainy period is May 3, the beginning date of the MS rainy period is June 27, the ending day of the CV rainy period is defined as the day before the beginning date of the MS rainy period, and the ending date of the MS rainy period is August 29. Meanwhile, corresponding anomaly analysis at a 500-hPa geopotential height, 850-hPa wind, Omega and relative humidity fields all show that the definitions of the average beginning and ending dates of the CV and MS rainy periods have a certain circulation meaning. Furthermore, the daily evolution of the CV index, meridional and zonal wind index, etc. all show that these objectively defined beginning and ending dates of the CV and MS rainy periods have climate significance. 展开更多
关键词 Northeast China cold vortex rainy period mid-summer rain period objective identification method
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Perceptual Quality Assessment of Omnidirectional Images:Subjective Experiment and Objective Model Evaluation 被引量:1
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作者 DUAN Huiyu ZHAI Guangtao +3 位作者 MIN Xiongkuo ZHU Yucheng FANG Yi YANG Xiaokang 《ZTE Communications》 2019年第1期38-47,共10页
Virtual reality(VR) environment can provide immersive experience to viewers.Under the VR environment, providing a good quality of experience is extremely important.Therefore, in this paper, we present an image quality... Virtual reality(VR) environment can provide immersive experience to viewers.Under the VR environment, providing a good quality of experience is extremely important.Therefore, in this paper, we present an image quality assessment(IQA) study on omnidirectional images. We first build an omnidirectional IQA(OIQA) database, including 16 source images with their corresponding 320 distorted images. We add four commonly encountered distortions. These distortions are JPEG compression, JPEG2000 compression, Gaussian blur, and Gaussian noise. Then we conduct a subjective quality evaluation study in the VR environment based on the OIQA database. Considering that visual attention is more important in VR environment, head and eye movement data are also tracked and collected during the quality rating experiments. The 16 raw and their corresponding distorted images,subjective quality assessment scores, and the head-orientation data and eye-gaze data together constitute the OIQA database. Based on the OIQA database, we test some state-of-the-art full-reference IQA(FR-IQA) measures on equirectangular format or cubic formatomnidirectional images. The results show that applying FR-IQA metrics on cubic format omnidirectional images could improve their performance. The performance of some FR-IQA metrics combining the saliency weight of three different types are also tested based on our database. Some new phenomena different from traditional IQA are observed. 展开更多
关键词 perceptual quality assessment OMNIDIRECTIONAL IMAGES SUBJECTIVE EXPERIMENT objective model evaluation VISUAL SALIENCY
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Optimality and Duality on Fractional Multi-objective Programming Under Semilocal E-convexity 被引量:1
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作者 HU Qing-jie XIA O Yun-hai CHEN Nei-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第2期200-210,共11页
In this paper, some necessary and sufficient optimality conditions are obtained for a fractional multiple objective programming involving semilocal E-convex and related functions. Also, some dual results are establish... In this paper, some necessary and sufficient optimality conditions are obtained for a fractional multiple objective programming involving semilocal E-convex and related functions. Also, some dual results are established under this kind of generalized convex functions. Our results generalize the ones obtained by Preda[J Math Anal Appl, 288(2003) 365-382]. 展开更多
关键词 semilocal E-convex functions fractional multiple objective programming optimality conditions DUALITY
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Development Progress of China’s First Mars Exploration Mission:Its Scientific Objectives and Payloads 被引量:1
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作者 JIA Yingzhuo ZOU Yongliao +4 位作者 ZHU Yan DU Qingguo FAN Yu CHEN Yuesong WANG Chi 《空间科学学报》 CAS CSCD 北大核心 2020年第5期693-697,共5页
China’s first Mars exploration mission is scheduled to be launched in 2020.It aims not only to conduct global and comprehensive exploration of Mars by use of an orbiter but also to carry out in situ observation of ke... China’s first Mars exploration mission is scheduled to be launched in 2020.It aims not only to conduct global and comprehensive exploration of Mars by use of an orbiter but also to carry out in situ observation of key sites on Mars with a rover.This mission focuses on the following studies:topography,geomorphology,geological structure,soil characteristics,water-ice distribution,material composition,atmosphere and ionosphere,surface climate,environmental characteristics,Mars internal structure,and Martian magnetic field.It is comprised of an orbiter,a lander,and a rover equipped with 13 scientific payloads.This article will give an introduction to the mission including mission plan,scientific objectives,scientific payloads,and its recent development progress. 展开更多
关键词 China’s first Mars exploration mission Scientific objectives Scientific payloads
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Non-Intrusive Objective Speech Quality Measurement Based on Fuzzy GMM and SVR for Narrowband Speech
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作者 王晶 张莹 +1 位作者 赵胜辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2010年第1期76-81,共6页
Based on fuzzy Gaussian mixture model (FGMM) and support vector regression (SVR),an improved version of non-intrusive objective measurement for assessing quality of output speech without inputting clean speech is ... Based on fuzzy Gaussian mixture model (FGMM) and support vector regression (SVR),an improved version of non-intrusive objective measurement for assessing quality of output speech without inputting clean speech is proposed for narrowband speech.Its perceptual linear predictive (PLP) features extracted from clean speech and clustered by FGMM are used as an artificial reference model.Input speech is separated into three classes,for each a consistency parameter between each feature pair from test speech signals and its counterpart in the pre-trained FGMM reference model is calculated and mapped to an objective speech quality score using SVR method.The correlation degree between subjective mean opinion score (MOS) and objective MOS is analyzed.Experimental results show that the proposed method offers an effective technique and can give better performances than the ITU-T P.563 method under most of the test conditions for narrowband speech. 展开更多
关键词 non-intrusive measurement objective speech quality fuzzy Gaussian mixture model (FGMM) support vector regression (SVR)
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Energy is the Objective, Material is the Fundamental, and Nanotechnology is the Approach
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作者 Zhiming M. Wang 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第4期325-325,共1页
This Special Section on Energy,Materials,and Nanotechnology(EMN),Journal of Electronic Science and Technology(JEST),presents a broad range of interdisciplinary and multidisciplinary research into cutting-edge scientif... This Special Section on Energy,Materials,and Nanotechnology(EMN),Journal of Electronic Science and Technology(JEST),presents a broad range of interdisciplinary and multidisciplinary research into cutting-edge scientific concepts towards materials synthesis,characterization,and novel technology developments.Climate change and environmental degradation partly stem from the global energy crisis we faced with today and have 展开更多
关键词 Energy is the objective Material is the Fundamental
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Salient Object Detection Based on a Novel Combination Framework Using the Perceptual Matching and Subjective-Objective Mapping Technologies
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作者 Jian Han Jialu Li +3 位作者 Meng Liu Zhe Ren Zhimin Cao Xingbin Liu 《Journal of Beijing Institute of Technology》 EI CAS 2023年第1期95-106,共12页
The integrity and fineness characterization of non-connected regions and contours is a major challenge for existing salient object detection.The key to address is how to make full use of the subjective and objective s... The integrity and fineness characterization of non-connected regions and contours is a major challenge for existing salient object detection.The key to address is how to make full use of the subjective and objective structural information obtained in different steps.Therefore,by simulating the human visual mechanism,this paper proposes a novel multi-decoder matching correction network and subjective structural loss.Specifically,the loss pays different attentions to the foreground,boundary,and background of ground truth map in a top-down structure.And the perceived saliency is mapped to the corresponding objective structure of the prediction map,which is extracted in a bottom-up manner.Thus,multi-level salient features can be effectively detected with the loss as constraint.And then,through the mapping of improved binary cross entropy loss,the differences between salient regions and objects are checked to pay attention to the error prone region to achieve excellent error sensitivity.Finally,through tracking the identifying feature horizontally and vertically,the subjective and objective interaction is maximized.Extensive experiments on five benchmark datasets demonstrate that compared with 12 state-of-the-art methods,the algorithm has higher recall and precision,less error and strong robustness and generalization ability,and can predict complete and refined saliency maps. 展开更多
关键词 salient object detection subjective-objective mapping perceptional separation and matching error sensitivity non-connected region detection
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Investment Objectives and Priorities of China Petroleum Industry Oriented to 2000
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作者 Peng Qing(Beijing Petroleum Managers Training Institute)Subjects: Investment, Decision analysis, External Cooperation 《China Oil & Gas》 CAS 1998年第2期70-72,共3页
关键词 2010 Investment objectives and Priorities of China Petroleum Industry Oriented to 2000
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Subjective V.S Objective Test Item
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作者 陶永艳 《海外英语》 2011年第4X期129-129,共1页
In this article,I will talk about the definition and discrimination of subjective test and objective test.The strong points and weak points are also discussed.Although each has its own disadvantages,subjective test an... In this article,I will talk about the definition and discrimination of subjective test and objective test.The strong points and weak points are also discussed.Although each has its own disadvantages,subjective test and objective test will still play important roles at present or in future.A good classroom test will usually contain both subjective and objective test items. 展开更多
关键词 SUBJECTIVE and objective TEST LANGUAGE
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The use of “Objective Correlative” Theory in T.S. Eliot’s The Love Song of J.Alfred Prufrock
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作者 狄思云 《海外英语》 2019年第9期173-174,176,共3页
“Objective Correlative”theory was first proposed by T.S. Eliot, who holds that people’s emotion can find expression in a series of objective correlative. In his poem The Love Song of J.Alfred Prufrock, the use of o... “Objective Correlative”theory was first proposed by T.S. Eliot, who holds that people’s emotion can find expression in a series of objective correlative. In his poem The Love Song of J.Alfred Prufrock, the use of objective correlative fully reflects and reveals modern people’s loneliness, futility and alienation. 展开更多
关键词 objective correlative”theory T.S ELIOT the love song of J.Alfred PRUFROCK ALLUSION FUTILITY alienation
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Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers
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作者 Feng He Sitong Chen +3 位作者 Ruili Zhou Hanyu Diao Yangyang Han Xiaodong Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期361-377,共17页
Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors c... Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static stimuli.Here,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic stimuli.Specifically,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential differences.The controllable and reversible polarization process of the conjugated polymers is fully in situ characterized.Then,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference outputs.Compared with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior bio-friendliness.As demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning algorithms.This tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins. 展开更多
关键词 Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition
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Detecting the core of a network by the centralities of the nodes
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作者 马佩杰 任学藻 +1 位作者 朱军芳 蒋艳群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期615-621,共7页
Many networks exhibit the core/periphery structure.Core/periphery structure is a type of meso-scale structure that consists of densely connected core nodes and sparsely connected peripheral nodes.Core nodes tend to be... Many networks exhibit the core/periphery structure.Core/periphery structure is a type of meso-scale structure that consists of densely connected core nodes and sparsely connected peripheral nodes.Core nodes tend to be well-connected,both among themselves and to peripheral nodes,which tend not to be well-connected to other nodes.In this brief report,we propose a new method to detect the core of a network by the centrality of each node.It is discovered that such nodes with non-negative centralities often consist in the core of the networks.The simulation is carried out on different real networks.The results are checked by the objective function.The checked results may show the effectiveness of the simulation results by the centralities of the nodes on the real networks.Furthermore,we discuss the characters of networks with the single core/periphery structure and point out the scope of the application of our method at the end of this paper. 展开更多
关键词 complex network core/periphery structure the objective function
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