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Preparation and spectral properties of blue-to-UVB upconverting Y 2 O 3 :RE 3+ ,Gd 3+ (RE = Er, Ho) micro-/nano-phosphors

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Journal of Rare Earths 2025年

作者： Dechao Yu Xiaoshan Zhang Arend Zhang Xinxin Han Enhai Song Dawei Zhang Engineering Research Center of Optical Instrument and System The Ministry of Education Shanghai Key Laboratory of Modern Optical System University of Shanghai for Science and Technology Shanghai 200093 China Condensed Matter and Interfaces Debye Institute for Nanomaterials Science Utrecht University Princetonplein 5 3584 CC Utrecht The Netherlands MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials Guangxi University Nanning 530004 China State Key Laboratory of Luminescent Materials and Devices School of Materials Science and Engineering South China University of Technology Guangzhou 510641 China

Phototherapeutic applications gain more and more interests and require fundamental progresses in interdisciplinarity research, particularly a novel topical phototherapy using ultraviolet-B (UVB, ∼310 nm) upconverting phosphors. In this study, three synthesis methods with(out) sintering processes were implemented to obtain micro-/nano-size Y 2 O 3 :RE 3+ /Gd 3+ (RE = Er, Ho) particles using RE oxides (RE 2 O 3 ), RE-nitrates (RE(NO 3 ) 3 ) and RE-chlorides (RECl 3 ) as starting materials. Pumped by an OPO laser at wavelengths of 450 and/or 490 nm, blue-to-UVB upconversion with narrowband peak at 313 nm was effectively realized for all the Y 2 O 3 :RE 3+ /Gd 3+ powder phosphors. On basis of theoretical speculations and experimental data, a two-photon absorption process was proposed for the UVB upconversion of Y 2 O 3 :RE 3+ /Gd 3+ . Moreover, the involved energy transfer (ET) from RE 3+ to Gd 3+ , its back ET mechanisms as well as cross-relaxation between RE 3+ (RE = Er, Ho) ions were systematically treated versus the Er 3+ - or Ho 3+ -, and Gd 3+ -doping concentration. Note that the UVB upconversion intensity will decline severely as the particles become smaller to submicron and nanoscale, likely due to an increasing surface-to-volume ratio along with more surface defects appearance. All these results would greatly promote the development of novel blue-to-UVB upconverting materials, and their potential applications in topical phototherapy irradiated by blue light source.

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Non-Cooperative Differential Game Based Energy Consumption Control for Dynamic Demand Response in Smart Grid

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China Communications 2019年第8期16卷 107-114页

作者： Manxi Wang Haitao Xu Shengsong Yang Lifeng Yang Ruifeng Duan Xianwei Zhou State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang 471003China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China

In this paper, we conduct research on the dynamic demand response problem in smart grid to control the energy consumption. The objective of the energy consumption control is constructed based on differential game, as the dynamic of each users’ energy state in smart gird can be described based on a differential equation. Concept of electricity sharing is introduced to achieve load shift of main users from the high price hours to the low price hours. Nash equilibrium is given based on the Hamilton equation and the effectiveness of the proposed model is verified based on the numerical simulation results.

关键词： energy consumption dynamic demand response smart grid differential game nash equilibrium

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Modeling Method and Application of Rational Finite Element Based on Absolute Nodal Coordinate Formulation

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Acta Mechanica Solida Sinica 2018年第2期31卷 207-228页

作者： Chao Ma Cheng Wei Jing Sun Bin Liu Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering Department of Aerospace Engineering Harbin Institute of Technology

In multibody system dynamics, the absolute nodal coordinate formulation （ANCF） uses power functions as interpolating polynomials to describe the displacement field. It can get accurate results for flexible bodies that undergo large deformation and large rotation. However, the power functions are irrational representation which cannot describe the complex shapes precisely, especially for circular and conic sections. Different from the ANCF representation, the rational absolute nodal coordinate formulation （RANCF） utilizes rational basis functions to describe geometric shapes, which allows the accurate representation of complicated displacement and deformation in dynamics modeling. In this paper, the relationships between the rational surface and volume and the RANCF finite element are provided, and the generalized transformation matrices are established correspondingly. Using these transformation matrices, a new four-node three-dimensional RANCF plate element and a new eight-node three-dimensional RANCF solid element are proposed based on the RANCF. Numerical examples are given to demonstrate the applicability of the proposed elements. It is shown that the proposed elements can depict the geometric characteristics and structure configurations precisely, and lead to better convergence in comparison with the ANCF finite elements for the dynamic analysis of flexible bodies.

关键词： Multibody system dynamics Absolute nodal coordinate formulation Flexible deformation Spline representation Rational finite element

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Trajectory generation for quadrotor while tracking a moving target in cluttered environment

Trajectory generation for quadrotor while tracking a moving ...

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第三十九届中国控制会议

作者： Lele Xi Zhihong Peng Lei Jiao School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System

In this paper, we present a trajectory generation method for quadrotor while tracking a moving target with relative pattern. Compared to existing methods, safe flying zone, vehicle’s physical limits and smoothness are considered to ensure obstacles avoidance and real tracking flight. To tackle with the cluttered environment, a parallel Particle Swarm Optimization algorithm is applied to calculate the safe feasible waypoints for quadrotor with consideration of target’s predicted state and the realistic tracking pattern, as well as safety. Then, a multiple waypoints constraints motion planning method is applied and embed into a cost function for solving the problem of trajectories generation and robust tracking for quadrotor via convex optimization approach, ensuring the real-time planning, with the geometrical constraint of safe flight corridor for quadrotor. The effectiveness of proposed method is verified by numerical simulation experiments.

关键词： Target tracking Trajectory generation Waypoints constraint Convex optimization

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An Approach for Multi-Objective Obstacle Avoidance Using Dynamic Occupancy Grid Map 17

An Approach for Multi-Objective Obstacle Avoidance Using Dyn...

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17th IEEE International Conference on Mechatronics and Automation, ICMA 2020

作者： Liu, Yanjie Chen, Jiao Bai, Xinyu Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin Heilongjiang Province China Sinopec International Business Co. Ltd. No. 22 North Chaoyang Gate Street Chaoyang District Beijing China

ISBN: (纸本)9781728164151

Path planning in dynamic environments is an important guarantee for mobile robots to complete navigation tasks safely. However, human motion is unpredictable, changing its speed or direction arbitrarily, and traditional dynamic obstacle avoidance strategies based on object detection require massive computing resources in the prediction step, which reduces the real time characteristics of the system. To address this question, we propose a dynamic obstacle avoidance framework. It defines the environment as a random dynamic system by using dynamic grid maps, and obtains the velocity of multiple objects with low delay under GPU parallel acceleration calculations. Naturally, we introduce the relative velocity into the artificial potential field function. By expanding the data structure of costmaps, the dynamic grid map is effectively connected with the local obstacle avoidance algorithm. Our approach reduces the detour time of the robot and improves the system security. © 2020 IEEE.

关键词： Mobile robots

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Simulation Research on Coordination of Electrical and Structural Parameters in Composite Insulator with Field Grading Materials

Simulation Research on Coordination of Electrical and Struct...

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Conference on Electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： Yangzhi Gong Jiale Wu Xupeng Song Wei Yang Kun Wang Xingming Bian State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources North China Electric Power University Beijing P.R.China State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research Institute Co. Ltd. Beijing P.R.China

Local overstress in composite insulators is a critical problem that affects insulation performance of high voltage transmission system. In addition to traditional methods, applying field grading materials (FGMs) with nonlinear electrical properties is also a promising method. To self-adaptively optimize the electric field strength distribution, electrical and structural parameters of FGMs need to be coordinated. Using finite element modeling, we examine the influence of FGMs with different electrical and structural parameters on field strength distribution of a 220kV AC transmission line epoxy composite insulator. The results indicate that the increase of non-linear coefficient has saturation effect on the reduction of local concentrated electric field strength. Non-linear coefficient of 10-20 is efficient for field grading. The coordination of threshold field strength and length of FGM layers is essential for the improvement of field strength distribution. And the increase of thickness of FGM layers also benefits field grading.

关键词： Power transmission lines Conferences Fitting High-voltage techniques Insulators Structural engineering Finite element analysis

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Closed-form integration of IMU error state covariance for optimization-based Visual-Inertial state Estimator

Closed-form integration of IMU error state covariance for op...

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第三十九届中国控制会议

作者： Xingbo Wang Zhihong Peng Lele Xi School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System

In this paper, we propose a closed-form IMU error state covariance integration method for optimization-based visualinertial state estimator. We derive a closed-form solutions of the IMU error state covariance propagation in pre-integration process, yielding improved accuracy of IMU residual information matrix. Our visual-inertial state estimator is based on a tightly-coupled, sliding-window optimization framework, which jointly estimate the IMU states and landmarks and performing marginalization to limit the computational cost. Finally, the system are validated in park environment dataset, the result shows our proposed method is effective.

关键词： visual-inertial state estimator pre-integration

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Advancing energy absorption in additively manufactured meta-plates through machine learning-driven inverse design

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Thin-Walled Structures 2025年 215卷

作者： Qingyuan Liu Liang Mou Lan Zhang Shuai Yuan Haiyang Peng Jinguo Ge Yunze Yang Yuhong Long Hualin Fan Guangxi Key Laboratory of Manufacturing System & Advanced Manufacturing Technology School of Mechanical and Electrical Engineering Guilin University of Electronic Technology Jinji road Guilin Guangxi 541004 China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Transportation safety systems (e.g., automotive crash boxes, train front-end energy absorption structures) require energy absorbers to simultaneously control energy absorption ( EA ), peak crushing force or stress ( PCF , PCS ), mean crushing force or stress ( MCF , MCS ), and undulation of load carrying ( ULC ). This study proposed meta-plates, characterized by stacking layers, twisting angles, and wall thicknesses. An additive manufacturing constrained machine learning and genetic algorithm (ML-GA) co-design framework was designed to optimize the crashworthiness performances. Finite element (FE) simulations incorporating nonlinear material models and contact algorithms, combined with Latin hypercube sampling, efficiently explored 10.7% of the design space, capturing nonlinear large deformations under quasi-static compression up to 50% strain. 600 independent samples were calculated to evaluate the performance of the ML model, which achieved 96.0% prediction accuracy ( R 2 score). At a given target relative density ( ρ ∗ ) ranging from 4% to 14%, the optimized meta-plates demonstrated 80%–200% higher MCS compared to benchmark shell/plate lattices at equivalent ρ ∗ . The meta-plates also exhibited directional crushing behavior with crushing force efficiency ( CFE ) around 1.0. Experimental validations show < 6% deviation from predictions also witnessed the high MCS , low PCS , and nearly free from stress fluctuation for meta-plates with 8%, 10%, and 14% ρ ∗ values. This methodology enables rapid design of lightweight energy absorbers with tunable deformation modes and extremely high material efficiency, providing a paradigm shift from trial-and-error approaches to intelligent crashworthy structure development.

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Generative Adversarial Network for Image Deblurring Using Content Constraint Loss

Generative Adversarial Network for Image Deblurring Using Co...

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第32届中国控制与决策会议

作者： Ye Ji Yaping Dai Junjie Ma Kaixin Zhao Yanyan Cheng School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System

The research of image deblurring plays an important role in the digital image *** order to reduce image blurring problems,a content constraint loss（CCL） function in the generative adversarial network（GAN）is *** SSIM loss and the perceptual loss constitute the CCL function,which makes the trained generative model *** CCL function as the content constraint loss component and the adversarial loss component constitute the total *** total loss is optimized by the iterative training to further improve the stability of the network model,and the image blurring will be *** the test experiment of the open source image dataset MNIST,CIFAR10/100 and CELEBA,the CCL function is used as the content constraint loss component of the generative adversarial network,the effect of image deblurring has obvious promotion in the structural similarity measure and visual appearance.

关键词： Image deblurring Generative adversarial network Content constraint loss Adversarial loss

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Target Assignment Optimization of Heterogeneous Sensor Networks in Urban Environment

Target Assignment Optimization of Heterogeneous Sensor Netwo...

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第三十九届中国控制会议

作者： Chen Chen Cheng Zihao Xu Wei School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System

Preventing and controlling Low-Slow-Small(LSS) targets are problems to be solved due to their good concealment in urban environment. Consequently, the problem of target assignment is studied in this paper. Firstly, a target assignment model based on heterogeneous sensor networks is proposed. The characteristics of LSS targets and the influence of environmental factors such as climate and terrain are considered on this model. At the same time, the detection capabilities of different detection nodes and collaborative tracking capabilities are also considered. Secondly, an intelligent optimization algorithm GSAPSO based on PSO is proposed to maximize tracking effect of the sensors. Finally, the simulations are used to compare the GSAPSO algorithm with the traditional PSO and GAPSO algorithms. The results demonstrate that the proposed algorithm has better tracking effect.

关键词： Target assignment Urban environment Heterogeneous sensor networks PSO

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