检索结果-南通市图书馆

Compact current-heating apparatus for SErF atomic magnetometer

在线全文

学校读者我要写书评

暂无评论

Compact current-heating apparatus for SERF atomic magnetomet...

Three-Dimensional probabilistic Neural Network Using for Mr Image Segmentation

Measurement Touch the World——IEEE 2011 10th International Conference on electronic Measurement & Instruments(ICEMI’2011)

作者： Tang Xingbin 1,2 Dong Haifeng 1,2 1.school of instrumentation science and opto-electronics engineering,beihang university,beijing 100191,china 2.National Key Laboratory of Inertial Technology,beihang university,beijing 100191,china

The pin-exchange relaxation-free （SErF） atomic magnetometer is one of the ultra-sensitive magnetometers,which must be operated in a low magnetic field and heated more than 100 .One of the main engineering difficulties in fabricating a SErF atomic magnetometer is to develop a heater that introduces no additional magnetic noise into the measurement *** this paper,a novel compact current-heating scheme and apparatus for the SErF atomic magnetometer are *** thermal and magnetic simulations of this apparatus are carried out and the results of the simulations demonstrate the feasibility of this heating apparatus: the vapor cell can be heated to a temperature of 103 and magnetic field introduced in the magnetometer can be limited in 10nT.

关键词： spin-exchange relaxation-free (SErF) atomic magnetometer current-heating nonmagnetic heating

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Three-Dimensional Probabilistic Neural Network Using for MR ...

The Model Identification for Small Unmanned Aerial rotorcraft Based on Adaptive Ant Colony Algorithm

Measurement Touch the World——IEEE 2011 10th International Conference on electronic Measurement & Instruments(ICEMI’2011)

作者： Lian Yuanfeng1 Wu Falin 2 1.College of Geophysics and Information engineering,china university of petroleum,beijing 102249,china 2.school of instrumentation science and opto-electronic engineering,beijing university of Aeronautics and Astronautics,beijing 100191,china

The three-dimensional probabilistic neural network（pNN）is proposed as the core classifier for segmentation of three-dimensional（3-D）magnetic resonance imaging（MrI）.The proposed algorithm takes into account the spatial information between image *** adopts the self-organizing map（SOM）neural network to overly segment the 3D Mr image,and yield reference voxels necessary for probabilistic density *** experimental results demonstrate the effectiveness and robustness of the proposed approach.

关键词： three-dimensional adaptive probabilistic neural network structure tensor Mr image segmentation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Bionic engineering 2012年第4期9卷 508-514页

作者： xusheng lei Kexin Guo school of Instrument science and opto-electronic engineering Beihang University Beijing 100191 P. R. China science and Technology on Inertial Laboratory Beijing 100191 P. R. China

This paper proposes a model identification method to get high performance dynamic model of a small unmanned aerial rotorcraft. With the analysis of flight characteristics, a linear dynamic model is constructed by the small perturbation theory. Using the micro guidance navigation and control module, the system can record the control signals of servos, the state infor- mation of attitude and velocity information in sequence. After the data preprocessing, an adaptive ant colony algorithm is proposed to get optimal parameters of the dynamic model. With the adaptive adjustment of the pheromone in the selection process, the proposed model identification method can escape from local minima traps and get the optimal solution quickly. performance analysis and experiments are conducted to validate the effectiveness of the identified dynamic model. Compared with real flight data, the identified model generated by the proposed method has a better performance than the model generated by the adaptive genetic algorithm. Based on the identified dynamic model, the small unmanned aerial rotorcraft can generate suitable control parameters to realize stable hovering, turning, and straight flight.

关键词： small unmanned aerial rotorcraft model identification adaptive ant colony

An Intelligent Ellipsoid Calibration Method Based on the Grey Wolf Algorithm for Magnetic Compass

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic engineering 2021年第2期18卷 453-461页

作者： xusheng lei Xiaoyu Zhang Yankun Hao school of the instrumentation science and opto-electronic engineering Beihang UniversityBeijing 100191China

With the measurement of the Earth’s magnetic field,magnetic compass can provide high frequency heading ***,it suffers from local magnetic *** intelligent ellipsoid calibration method based on the grey wolf is proposed to generate optimal parameters for magnetic compass to generate high performance heading *** the analysis of the projection relationship among the navigation coordinate frame,the body frame and the local horizontal frame,the heading ellipsoid equation is ***,an improved grey wolf algorithm is proposed to find optimization solution in a large solution *** the improvement of the convergence factor and the evolutionary mechanism,the improved grey wolf algorithm can generate optimized solution for heading ellipsoid *** effectiveness of the proposed method has been verified by a series of vehicle and flight *** experimental results show that the proposed method can eliminate errors caused by sensor defects,hard-iron interference,and soft-iron interference *** heading error generated by the magnetic compass is less than 0.2162 degree in real flight tests.

关键词： magnetic compass ellipsoid parameters grey wolf algorithm error model

Numerical simulation and experiment study on optothermal response of multilayer biological tissue under pulse laser irradiation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical simulation and experiment study on optothermal res...

Fault tolerant control based on stochastic distribution via rBF neural networks

photonics Asia 2004;Sensors and Imaging

作者： Hongqin Yang*l3, Shusen Xie 1,2 Zukang Lu 1.State Key Laboratory ofModern Optical instrumentation, Zhejiang university, Hangzhou, Zhejiang 310027, china 2.school of physics and optoelectronics Technology, Fujian Normal university, Fuzhou, Fujian 350007, china 3.Department of electronic science and Applied physics, Fuzhou university, Fuzhou, Fujian 350007, china

In this study, a novel multilayer-tissue heat transfer model for laser-induced optothermal response is presented by considering the heterogeneous properties of biological tissue. Various temperature m

关键词： temperature measurement, numerical simulation, pulse laser, mammalian skin tissue

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Systems engineering and electronics 2011年第1期22卷 63-69页

作者： Zakwan Skaf Hong Wang lei Guo school of Electrical and electronic engineering The University of Manchester Manchester M60 1QD UK school of instrumentation science and opto-electronics engineering Beihang University Beijing 100191 P. R. China

A new fault tolerant control（FTC） via a controller reconfiguration approach for general stochastic nonlinear systems is *** from the formulation of classical FTC methods,it is supposed that the measured information for the FTC is the probability density functions（pDFs） of the system output rather than its measured value.A radial basis functions（rBFs） neural network technique is proposed so that the output pDFs can be formulated in terms of the dynamic weighings of the rBFs neural *** a result,the nonlinear FTC problem subject to dynamic relation between the input and the output pDFs can be transformed into a nonlinear FTC problem subject to dynamic relation between the control input and the weights of the rBFs neural network approximation to the output *** FTC design consists of two *** first step is fault detection and diagnosis（FDD）,which can produce an alarm when there is a fault in the system and also locate which component has a *** second step is to adapt the controller to the faulty case so that the system is able to achieve its target.A linear matrix inequality（LMI） based feasible FTC method is applied such that the fault can be detected and *** illustrated example is included to demonstrate the efficiency of the proposed algorithm,and satisfactory results have been obtained.

关键词： probability density function(pDF) nonlinear stochastic system fault tolerant control(FTC).

Synthesis, mechanical investigation, and application of nitrogen and phosphorus co-doped carbon dots with a high photoluminescent quantum yield

在线全文

学校读者我要写书评

暂无评论

Nano research 2018年第7期11卷 3691-3701页

作者： Quan Xu Bofan Li Yingchun Ye Wei Cai Weijun Li Chuanyao Yang Yusheng Chen Meng Xu Neng Li xusheng Zheng Jason Street Yan Luo Lulu Cai State Key Laboratory of Heavy Oil processing China University ofPetroleum (Beijing) Beijing 102249 China Department of pharmacy Sichuan Academy of Medical Science & Sichuan Provincial People's Hospital School of Medicine University of Electronic Science and Technology of China Chengdu 610072 China Department of Chemistry University of Akron Akron Ohio 44325 USA Department of Orthopedics General Hospital of Chinese People's Liberation Army Beijing 100853 China State Key Laboratory of Silicate Materials forArchitectures Wuhan University of Technology Wuhan 430070 China National Synchrotron radiation Laboratory (NSrL) University of Science and Technology of China Hetei 230029 China Department of Sustainable Bioproducts Mississippi State University Starkville MS 39762 USA Department of Chemical engineering West Virginia University Morgantown WV26506 USA

Heteroatom-doped carbon dots （CDs） with a high photoluminescent quantum yield （pLQY） have recently attracted attention due to their applications in chemical sensors, photocatalysis, bioimaging, and drug delivery. Nitrogen and phosphorus are in close proximity to carbon in the periodic table and are key tracking elements in the field of biomedical imaging. These two elements alter the optical and electronic properties of CDs and help improve the fundamental understanding of their pLQY. This can also lead to multifunctional usage in photoimaging and photothermal therapy. However, most pLQYs resulting from the synthesis of p-doped CDs are currently below 50%. These CDs have limited usefulness in the fields of bioimaging and drug delivery. In this study, a single-step, high-efficiency hydrothermal method was applied to synthesize nitrogen and phosphorous-doped carbon dots （（N,p）-CDs） with a pLQY of up to 53.8% with independent emission behavior. Moreover, the CDs presented high monodispersity, robust excitation-independent luminescence, and stability over a large pH range. Spectroscopic investigations indicated that the pLQY of the （N,p）-CDs was primarily due to the addition of p and the passivation effect of the oxidized surface. The excellent fluorescence properties of （N,p）-CDs can be effectively and selectively quenched by Hg2~ ions. Such systems show a linear response in the 0-900 nM concentration range with a short response time, indicating their potential for applications in the fields of chemistry and biology.

关键词： carbon dots photoluminesce ncemechanism nanosensor density functional theory

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于无人机的“自动控制原理”教学探索

电气电子教学学报 2022年第1期44卷 84-86页

作者：雷旭升北京航空航天大学仪器科学与光电工程学院北京100191

针对“自动控制原理”课程教学中存在学和用两张皮、授课模式单一和学生动手能力差等问题,设计低成本、开放性强的无人旋翼机实践教学平台。通过首尾闭环教学模式和课堂交互模式的优化改进,提高学生对课堂知识点的理解、掌握能力,并优... 详细信息

针对“自动控制原理”课程教学中存在学和用两张皮、授课模式单一和学生动手能力差等问题,设计低成本、开放性强的无人旋翼机实践教学平台。通过首尾闭环教学模式和课堂交互模式的优化改进,提高学生对课堂知识点的理解、掌握能力,并优化改进评估体系,促进学生重视控制理论在实际工程中的应用。改革后的教学方法在教学实践中取得了良好的效果。

关键词：自动控制原理无人旋翼机实践教学平台首尾闭环课堂教学

在线全文

学校读者我要写书评

暂无评论

基于多模型模糊融合的MEMS陀螺补偿方法

传感器与微系统 2019年第6期38卷 46-47,52页

作者：耿越雷旭升北京航空航天大学仪器科学与光电工程学院北京100191

为了实现微机电系统(MEMS)陀螺的高精度补偿,本文借助分段线性拟合与多模型模糊融合的方法,得到了一种新的标定补偿算法。通过对各轴分段组合的标定数据进行拟合建立多组补偿模型,并通过角速率的隶属度函数的模糊加权实现多模型融合,得... 详细信息

为了实现微机电系统(MEMS)陀螺的高精度补偿,本文借助分段线性拟合与多模型模糊融合的方法,得到了一种新的标定补偿算法。通过对各轴分段组合的标定数据进行拟合建立多组补偿模型,并通过角速率的隶属度函数的模糊加权实现多模型融合,得到随测量值变化的线性补偿模型,提高了陀螺输出补偿的精度。实验表明,该方法的补偿精度明显优于传统方法。其算法简单计算量小,易于在实际工程中应用。

关键词：多模型模糊融合微机电系统(MEMS)陀螺输出补偿