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期刊论文 8

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2023 1

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2019 1

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2015 2

关键词

图像秘密分享；影子图像验证；公钥；像素扩张；无损恢复 1

大规模天线阵列；信道建模；5G；阴影衰落；时延扩展；匹配滤波器；香农容量；信道状态数；信道富裕度 1

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Amethod of shadowpuppet figure modeling and animation

Xiao-fang HUANG,Shou-qian SUN,Ke-jun ZHANG,Tian-ning XU,Jian-feng WU,Bin ZHU

《信息与电子工程前沿（英文）》 2015年第16卷第5期页码 367-379 doi: 10.1631/FITEE.1400351

摘要： To promote the development of the intangible cultural heritage of the world, shadow play, many studies have focused on shadow puppet modeling and interaction. Most of the shadow puppet figures are still imaginary, spread by ancients, or carved and painted by shadow puppet artists, without consideration of real dimensions or the appearance of human bodies. This study proposes an algorithm to transform 3D human models to 2D puppet figures for shadow puppets, including automatic location of feature points, automatic segmentation of 3D models, automatic extraction of 2D contours, automatic clothes matching, and animation. Experiment proves that more realistic and attractive figures and animations of the shadow puppet can be generated in real time with this algorithm.

关键词： Shadow play Shadow puppet figure 3D human body Data processing 2D modeling

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雾霾给太阳蒙上阴影

Jane Palmer

《工程（英文）》 2019年第5卷第6期页码 989-990 doi: 10.1016/j.eng.2019.10.009

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rate-dependent Prandtl-Ishlinskii model for piezoelectric actuators using the dynamic envelope function based play

Meiju YANG,Chunxia LI,Guoying GU,Limin ZHU

《机械工程前沿（英文）》 2015年第10卷第1期页码 37-42 doi: 10.1007/s11465-015-0326-1

摘要：

In this paper, a novel rate-dependent Prandtl-Ishlinskii (P-I) model is proposed to characterize the rate-dependent hysteresis nonlinearity of piezoelectric actuators. The new model is based on a modified rate-dependent play operator, in which a dynamic envelope function is introduced to replace the input function of the classical play operator. Moreover, a dynamic density function is utilized in the proposed P-I model. The parameters of the proposed model are identified by a modified particle swarm optimization algorithm. Finally, experiments are conducted on a piezo-actuated nanopositioning stage to validate the proposed P-I model under the sinusoidal inputs. The experimental results show that the developed rate-dependent P-I model precisely characterize the rate-dependent hysteresis loops up to 1000 Hz.

关键词： piezoelectric actuators hysteresis Prandtl-Ishlinskii rate-dependent

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基于公钥具有双向影子图像验证功能且无像素扩张的图像秘密分享 Research Article

Xuehu Yan, Longlong Li, Jia Chen, Lei Sun

《信息与电子工程前沿（英文）》 2023年第24卷第1期页码 88-103 doi: 10.1631/FITEE.2200118

摘要：图像秘密分享（ISS）的研究越来越多，主要因为数字图像的重要性以及ISS可以广泛应用于云分布式存储和多方安全计算。影子图像认证日渐重要，通常包括影子图像真实性检测和识别。然而，传统处理者参与的方法主要是单向验证，即在解码阶段验证影子图像，存在像素扩张或额外辅助信息等不足。因此，分发（编码）阶段的影子图像认证对参与者来说也很重要。本文引入一种基于公钥的双向影子图像认证方法，实现(k, n)门限且无像素扩张。当处理者将每个影子图像分发给相应参与者时，参与者可以用其私钥验证接收到的影子图像。在解码阶段，处理者可以用其秘钥验证每个接收到的影子图像；此外，当获得任何k个或更多影子图像时，处理者可以无损解码秘密图像。理论分析、实验和比较验证了所提方法有效性。

关键词：图像秘密分享；影子图像验证；公钥；像素扩张；无损恢复

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Tracing the impact of stack configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy

《环境科学与工程前沿（英文）》 2022年第16卷第4期 doi: 10.1007/s11783-021-1480-9

摘要：

• RED performance and stack resistance were studied by EIS and LSV.

关键词： Reverse electrodialysis Electrochemical impedance spectroscopy Concentration polarization Spacer shadow effect

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Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

Binrong WEN, Sha WEI, Kexiang WEI, Wenxian YANG, Zhike PENG, Fulei CHU

《机械工程前沿（英文）》 2017年第12卷第3期页码 321-332 doi: 10.1007/s11465-017-0434-1

摘要：

The magnitude and stability of power output are two key indices of wind turbines. This study investigates the effects of wind shear and tower shadow on power output in terms of power fluctuation and power loss to estimate the capacity and quality of the power generated by a wind turbine. First, wind speed models, particularly the wind shear model and the tower shadow model, are described in detail. The widely accepted tower shadow model is modified in view of the cone-shaped towers of modern large-scale wind turbines. Power fluctuation and power loss due to wind shear and tower shadow are analyzed by performing theoretical calculations and case analysis within the framework of a modified version of blade element momentum theory. Results indicate that power fluctuation is mainly caused by tower shadow, whereas power loss is primarily induced by wind shear. Under steady wind conditions, power loss can be divided into wind farm loss and rotor loss. Wind farm loss is constant at 3α(3α−1)R²/(8H²). By contrast, rotor loss is strongly influenced by the wind turbine control strategies and wind speed. That is, when the wind speed is measured in a region where a variable-speed controller works, the rotor loss stabilizes around zero, but when the wind speed is measured in a region where the blade pitch controller works, the rotor loss increases as the wind speed intensifies. The results of this study can serve as a reference for accurate power estimation and strategy development to mitigate the fluctuations in aerodynamic loads and power output due to wind shear and tower shadow.

关键词： wind turbine wind shear tower shadow power fluctuation power loss

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Shadow obstacle model for realistic corner-turning behavior in crowd simulation

Gao-qi HE,Yi JIN,Qi CHEN,Zhen LIU,Wen-hui YUE,Xing-jian LU

《信息与电子工程前沿（英文）》 2016年第17卷第3期页码 200-211 doi: 10.1631/FITEE.1500253

摘要： This paper describes a novel model known as the shadow obstacle model to generate a realistic corner-turning behavior in crowd simulation. The motivation for this model comes from the observation that people tend to choose a safer route rather than a shorter one when turning a corner. To calculate a safer route, an optimization method is proposed to generate the corner-turning rule that maximizes the viewing range for the agents. By combining psychological and physical forces together, a full crowd simulation framework is established to provide a more realistic crowd simulation. We demonstrate that our model produces a more realistic corner-turning behavior by comparison with real data obtained from the experiments. Finally, we perform parameter analysis to show the believability of our model through a series of experiments.

关键词： Corner-turning behavior Crowd simulation Safety awareness Rule-based model

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Indoor massive multiple-input multiple-output channel characterization and performance evaluation Article

Jian-zhi LI, Bo AI, Rui-si HE, Qi WANG, Mi YANG, Bei ZHANG, Ke GUAN, Dan-ping HE, Zhang-dui ZHONG, Ting ZHOU, Nan LI

《信息与电子工程前沿（英文）》 2017年第18卷第6期页码 773-787 doi: 10.1631/FITEE.1700021

摘要：介绍了室内环境下的大规模天线阵列信道测量，天线阵列形式包括64阵元虚拟线阵、64阵元虚拟面阵以及128阵元虚拟面阵。3种不同形式的阵列结构通过三维机械转台构造得到。测量频点包括2、4、6、11、15以及22 GHz，测量带宽为200 MHz。测量同时考虑了直射径场景和非直射径场景。对实测数据进行了基本信道参数萃取，参数包括路径损耗、阴影衰落、功率时延谱和均方根时延扩展。同时给出了上述信道参数的频率依赖性分析，以及阴影衰落与均方根时延扩展的相关性分析。利用实测数据，对基于匹配滤波器的码间干扰消除性能进行了评估，给出了其他信道性能指标如信道香农容量、信道状态数以及信道富裕度的分析结果。分析结果表明：对于具有丰富反散射体的室内环境，即使在直射径存在的情况下，实际大规模天线阵列信道的性能可以接近于独立同分布瑞利信道。

关键词：大规模天线阵列；信道建模；5G；阴影衰落；时延扩展；匹配滤波器；香农容量；信道状态数；信道富裕度

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标题作者时间类型操作

Amethod of shadowpuppet figure modeling and animation

Xiao-fang HUANG,Shou-qian SUN,Ke-jun ZHANG,Tian-ning XU,Jian-feng WU,Bin ZHU

期刊论文

雾霾给太阳蒙上阴影

Jane Palmer

期刊论文

rate-dependent Prandtl-Ishlinskii model for piezoelectric actuators using the dynamic envelope function based play

Meiju YANG,Chunxia LI,Guoying GU,Limin ZHU

期刊论文