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关键词

CMOS；跨导提升技术；低噪声放大器；变压器；共栅级 1

图像秘密分享；影子图像验证；公钥；像素扩张；无损恢复 1

地球位系数模型 1

地球形状 1

地球重力场模型DQM99 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

控制 1

检测 1

水平预拼装 1

竖曲线形 1

计算 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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舟山西堠门跨海大桥分体式钢箱梁制造预拼装线形控制技术

徐亮,王辉平,张胜利,钱叶祥

《中国工程科学》 2010年第12卷第7期页码 43-46

摘要：

西堠门大桥钢加劲梁制造时采用水平预拼装的方法，为了保证梁段的制造竖曲线形，应先根据设计数据模拟计算得到竖曲线形相关参数，在水平预拼装时进行控制、调整，最后检测线形的精度，保证线形的正确性。

关键词：水平预拼装竖曲线形计算控制检测

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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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Developments in semiconductor thermoelectric materials

Laifeng LI, Zhen CHEN, Min ZHOU, Rongjin HUANG

《能源前沿（英文）》 2011年第5卷第2期页码 125-136 doi: 10.1007/s11708-011-0150-1

摘要： A surge in interest in developing alternative renewable energy technologies has been observed in recent years. In particular, thermoelectrics has drawn attention because thermoelectric effects enable direct conversion between thermal and electrical energy, and provide power generation and refrigeration alternatives. During the past decade, the performance of thermoelectric materials has been considerably improved; however, many challenges continue to exist. Developing thermoelectric materials with superior performance means tailoring interconnected thermoelectric physical parameters-electrical conductivities, Seebeck coefficients, and thermal conductivities for a crystalline system. The objectives of this paper are to introduce the recent developments in semiconductor thermoelectric materials, and briefly summarize the applications of such materials.

关键词： thermoelectric materials thermoelectric figure of merit applications

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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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Nanostructural thermoelectric materials and their performance

Kai-Xuan CHEN, Min-Shan LI, Dong-Chuan MO, Shu-Shen LYU

《能源前沿（英文）》 2018年第12卷第1期页码 97-108 doi: 10.1007/s11708-018-0543-5

摘要： In this review, an attempt was made to introduce the traditional concepts and materials in thermoelectric application and the recent development in searching high-performance thermoelectric materials. Due to the use of nanostructural engineering, thermoelectric materials with a high figure of merit are designed, leading to their blooming application in the energy field. One dimensional nanotubes and nanoribbons, two-dimensional planner structures, nanocomposites, and heterostructures were summarized. In addition, the state-of-the-art theoretical calculation in the prediction of thermoelectric materials was also reviewed, including the molecular dynamics (MD), Boltzmann transport equation, and non-equilibrium Green’s function. The combination of experimental fabrication and first-principles prediction significantly promotes the discovery of new promising candidates in the thermoelectric field.

关键词： nanostructural low-dimensional thermoelectric material figure of merit first-principles

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高分辨率地球重力场模型DQM99

石磐,夏哲仁,孙中苗,李迎春

《中国工程科学》 1999年第1卷第3期页码 51-55

摘要：

地球扰动位的球谐展开式表示是地球重力场模型应用最广泛的一种表示方法。目前通用的位系数模型的分辨率是0.5°，最高完全阶次为360。由于全球重力数据覆盖的密度和数据精度差别较大，所以已知的重力场模型的实际分辨率及其精度也因地区而异，故重力场模型的精化是一个漫长的过程，局部积分谱权综合法是改善已知重力场模型的有效而简便的方法。基于重力场模型OSU91A及EGM96，利用我国15′×15′及5′×5′重力异常，我们解算了更高阶次的地球重力场模型DQM99A、B、C、D四个模型，给出了精度比较分析结果。

关键词：地球重力场模型DQM99 地球形状地球位系数模型

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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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基于电感和变压器跨导提升技术、噪声系数为3.2 dB、带宽为9.8–30.1 GHz的CMOS低噪声放大器

陈宏尘1,朱浩慎1,吴亮2,车文荃1,薛泉1

《信息与电子工程前沿（英文）》 2021年第22卷第4期页码 586-598 doi: 10.1631/FITEE.2000510

摘要：随着第五代移动通信系统（5G）的到来，毫米波收发系统预期将陆续在世界范围内大规模商用部署。对于接收机来说，最关键的指标是要保持较高信噪比。因此，位于接收机前端的第一个有源模块——低噪声放大器——起着非常关键的作用。但是，当频率上升到毫米波段时，由于寄生效应影响变大，高性能的宽带低噪声放大器设计面临着诸多挑战。本文通过基于电感和变压器的跨导提升技术，研制一款宽带的高性能毫米波低噪声放大器。使用台积电（TSMC）65 nm CMOS工艺流片并测试，这款低噪声放大器最低噪声系数仅为3.2 dB，带宽高达20.3 GHz，适用于5G毫米波收发系统。利用共栅放大器(M1)和共源放大器（M2）级联构成完整的低噪声放大器。第一级选择共栅级是因为共栅放大器的输入阻抗低，易于实现宽带的输入匹配。但是，由于单纯的一级放大器增益不够，所以级联一个共源级作为第二级放大器提高增益。在低噪声放大器中，较高的增益通常需要更大功耗来实现，因此增益和功耗在实际设计中需要折中。但是，通过引入跨导提升技术，可以使得等效跨导Gm等于(1+A)gm，其中A是提升因子，gm是晶体管固有的跨导。如此，在同样功耗（gm）下，引入跨导提升技术可取得更高增益（Gm）；反之，对于相同增益（Gm），引入跨导提升技术后只需要更小功耗（gm）。然而，传统的跨导提升方法，即通过有源反馈实现，会引入大量噪声。与传统方法不同，本文提出利用电感提升跨导和变压器提升跨导相结合的方式大幅提升第一级和第二级放大器的跨导。首先通过在第一级放大器（共栅级）加入栅极电感Lg，使Lg与晶体管M1的寄生电容在高频处谐振，从而提升M1的等效跨导。其次，针对第二级放大器（共源级），通过引入变压器TR1，使M2的栅极和源级同时输入反相信号，从而提升M2的等效跨导。通过仿真实验，可以看到引入电感后提升了第一级放大器的等效跨导。在第二级放大器引入变压器后等效跨导随耦合系数变化，可以看到，当耦合系数为0时，等效跨导最低，随着耦合系数增大，等效跨导提升。本文提出的宽带毫米波低噪声放大器经台积电65纳米CMOS工艺流片加工。去除测试PAD后的芯片面积仅为0.1 μm2。该低噪声放大器采用在片测试方法测试。其中，S参数由德国R&S公司生成的ZVA67矢量网络分析仪测试。噪声系数由带有噪声系数测试选件K30的FSW67频谱分析仪和Noisecom公司的噪声源NC346V测试。测试结果表明，低噪声放大器最大增益为10.9 dB，3 dB带宽从9.8 GHz到30.1 GHz，高达20.3 GHz，并且输入匹配良好。另外，噪声系数最低仅为3.2 dB，且在整个3 dB带宽内低于5.7 dB。此外，整体功耗仅为15.6 mW。由此可见，由于采用了基于电感和变压器的跨导提升技术，该毫米波低噪声放大器在带宽、增益和噪声系数方面表现优异，适用于5G毫米波收发系统。

关键词： CMOS；跨导提升技术；低噪声放大器；变压器；共栅级

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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

舟山西堠门跨海大桥分体式钢箱梁制造预拼装线形控制技术

徐亮,王辉平,张胜利,钱叶祥

期刊论文