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严格雪崩准则 2

自相关函数 2

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Mirror system based therapy for autism spectrum disorders

CHEN Wei, ZHANG Jing, DING Jun

《医学前沿（英文）》 2008年第2卷第4期页码 344-347 doi: 10.1007/s11684-008-0065-3

摘要： This paper reviews the present theories and empirical research of autisms’ cognitive research and mirror systems and introduces a new hypothesis about the causes of autism spectrum disorders (ASD): autistic mirror neuron dysfunction hypothesis. ASD subjects show obvious lack of the activation of the mirror system during the task of observation or emotional cognition. It is significant to investigate the mirror system for revealing the causes of autism and it is also helpful for developing new ways to diagnose or treat this disorder.

关键词： emotional cognition observation activation spectrum empirical research

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Solar fuel from photo-thermal catalytic reactions with spectrum-selectivity: a review

Sanli TANG, Jie SUN, Hui HONG, Qibin LIU

《能源前沿（英文）》 2017年第11卷第4期页码 437-451 doi: 10.1007/s11708-017-0509-z

摘要： Solar fuel is one of the ideal energy sources in the future. The synergy of photo and thermal effects leads to a new approach to higher solar fuel production under relatively mild conditions. This paper reviews different approaches for solar fuel production from spectrum-selective photo-thermal synergetic catalysis. The review begins with the meaning of synergetic effects, and the mechanisms of spectrum-selectivity and photo-thermal catalysis. Then, from a technical perspective, a number of experimental or theoretical works are sorted by the chemical reactions and the sacrificial reagents applied. In addition, these works are summarized and tabulated based on the operating conditions, spectrum-selectivity, materials, and productivity. A discussion is finally presented concerning future development of photo-thermal catalytic reactions with spectrum-selectivity.

关键词： photo-thermal catalysis spectrum-selectivity solar fuel full-spectrum

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Detection of geosmin and 2-methylisoborneol by liquid-liquid extraction-gas chromatograph mass spectrum(LLE-GCMS) and solid phase extraction-gas chromatograph mass spectrum (SPE-GCMS)

MA Xiaoyan, CHEN Beibei, LI Qingsong, ZHANG Qiaoli, GU Guofen

《环境科学与工程前沿（英文）》 2007年第1卷第3期页码 286-291 doi: 10.1007/s11783-007-0048-7

摘要： Two sample preparation methods were introduced and compared in this paper to establish a simple, quick and exact analysis of geosmin and 2-methylisoborneol. LC-18 column was employed in solid phase extraction (SPE), 1.0 mL of hexane was adopted in liquid-liquid extraction (LLE), and the extracts were analyzed by gas chromatograph mass spectrum (GCMS) in selected ion mode. Mean recoveries of SPE were low for 2-methylisoborneol (2-MIB) and geosmin (GSM) with values below 50%. For LLE, the recoveries were satisfyingly above 50% for 2-MIB and 80% for GSM. Detection limits of the LLE method were as low as 1.0 ng/L for GSM and 5.0 ng/L for 2-MIB. A year-long investigation on odor chemicals of drinking water in Shanghai demonstrated that in the summer, there was a serious odor problem induced by a high concentration of 2-MIB. The highest concentration of 152.82 ng/L appeared in July in raw water, while GSM flocculation was minimal with concentrations below odor threshold.

关键词： summer flocculation simple Shanghai spectrum

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Contact fatigue life prediction of a bevel gear under spectrum loading

Pan JIA, Huaiju LIU, Caichao ZHU, Wei WU, Guocheng LU

《机械工程前沿（英文）》 2020年第15卷第1期页码 123-132 doi: 10.1007/s11465-019-0556-8

摘要： Rolling contact fatigue (RCF) issues, such as pitting, might occur on bevel gears because load fluctuation induces considerable subsurface stress amplitudes. Such issues can dramatically affect the service life of associated machines. An accurate geometry model of a hypoid gear utilized in the main reducer of a heavy-duty vehicle is developed in this study with the commercial gear design software MASTA. Multiaxial stress–strain states are simulated with the finite element method, and the RCF life is predicted using the Brown–Miller–Morrow fatigue criterion. The patterns of fatigue life on the tooth surface are simulated under various loading levels, and the RCF curve is numerically generated. Moreover, a typical torque–time history on the driven axle is described, followed by the construction of program load spectrum with the rain flow method and the Goodman mean stress equation. The effects of various fatigue damage accumulation rules on fatigue life are compared and discussed in detail. Predicted results reveal that the Miner linear rule provides the most optimistic result among the three selected rules, and the Manson bilinear rule produces the most conservative result.

关键词： bevel gear rolling contact fatigue (RCF) multiaxial fatigue criterion load spectrum damage accumulation rule

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一种新的通信抗干扰技术体制：预编码跳码扩谱

姚富强,张毅

《中国工程科学》 2011年第13卷第10期页码 69-75

摘要：

基于常规直扩体制的不足，笔者分析了跳码扩谱的必要性，提出和研究了一种新的预编码跳码扩谱通信抗干扰技术体制，重点讨论了预编码跳码扩谱的基本原理与自编码跳码扩谱的异同点、关键技术等，最后分析了其基本性能。该体制和性能已在实际中得到初步验证。

关键词：通信抗干扰直接序列扩谱预编码跳码扩谱自编码跳码扩谱

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A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿（英文）》 2012年第6卷第1期页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要： This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词： in-line measurement particle size distribution (PSD) incident light intensity particle concentration light fluctuation

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密码函数的一类递归构造方法

滕吉红,张文英,刘文芬,李世取

《中国工程科学》 2003年第5卷第7期页码 47-52

摘要：

首先利用递归的方法证明了结构形式更为一般的布尔函数的Walsh谱分解式，然后利用这类布尔函数Walsh谱分解式，给出了密码学和编码学中具有重要应用价值的一些布尔函数，如弹性函数、Bent函数以及满足严格雪崩准则的布尔函数的构造方法。

关键词： Walsh谱 Walsh谱分解式 Bent函数弹性函数严格雪崩准则

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Measurement and analysis of tip clearance unsteady flow spectrum in axial-flow fan rotor

LIU Bo, HOU Weimin, MA Changyou, WANG Yangang, ZHOU Qiang

《能源前沿（英文）》 2008年第2卷第4期页码 448-452 doi: 10.1007/s11708-008-0088-0

摘要： The dynamic pressure measurement device and test technology are described in this study. The tip clearance unsteady flow development from the inlet to the outlet of an axial-flow rotor was revealed by analyzing pressure frequency spectrum acquired from measuring the unsteady pressure field of the tip endwall. The experiment provides test basis for thoroughly understanding the tip clearance unsteady flow and building interaction models of tip clearance flow and main flow.

关键词： development endwall unsteady pressure pressure measurement experiment

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基于双正交复序列的高效扩频调制方法

史小红

《中国工程科学》 2012年第14卷第3期页码 108-112

摘要：

提出了一种采用双正交复序列的高效扩频调制与解调方法（DoCS）。输入数据比特流被分割为长度为M的组，每组的M比特作为输入码字，从2M-2个长度为L的DoCS序列中选择一条序列进行发送，被选中的序列以QPSK方式调制在载波上，实现扩频通信。文中还提出了一种前向相位校正(FPC)方法来解决该系统中收发两端的载波同步问题。

关键词：调制与解调技术高效扩频调制前向相位校正双正交码

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平缓岸坡上波浪谱的变形及破碎

李玉成,崔丽芳,于洋,董国海,高家俊,庄士贤

《中国工程科学》 2000年第2卷第5期页码 51-59

摘要：

文章通过理论分析和实验研究，讨论了平缓岸坡条件下不规则波的破碎指标、波浪谱变形与破碎特点及其计算方法和不再发生破碎的岸坡条件，并与物模实验结果和现场观测结果进行比较，结果吻合较好。

关键词：波浪谱岸坡变形破碎

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泰州大桥钢桥面铺装轮载谱研究

李洪涛,潘友强,张志祥

《中国工程科学》 2012年第14卷第5期页码 85-89

摘要：

调研了江苏省内三座跨江大桥2007—2010年的交通量和交通荷载状况，利用轮载谱分析货车交通量和交通荷载状况，并推荐了江苏省内货车轮载和典型轮载比例；分析江苏省内三座跨江大桥的货车超载情况并给出了超载比例较大的车型。研究成果为泰州大桥钢桥面铺装设计研究提供了有力支持。

关键词：跨江大桥轮载谱轮载类型交通量交通荷载

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继承泰勒级数的关系谱分析：手部肌肉协同与耦合 Research Article

刘刚,王晶

《信息与电子工程前沿（英文）》 2022年第23卷第1期页码 145-157 doi: 10.1631/FITEE.2000578

摘要：数学中有两种著名的函数分解方法：泰勒级数和傅里叶级数。傅里叶级数发展成为傅里叶频谱，用于信号分解和分析；而泰勒级数的求解需要已知具体函数表达式，所以其在工程领域很少被应用。本文使用树突网络发展了泰勒级数，构造了关系谱，并将其应用于模型或系统分解和分析。了解肌肉激活与手指运动之间的直观联系对于开发无需用户预训练的商业假肢至关重要。然而，由于人手的复杂性，该直观联系尚未被理解。本文使用关系谱分析了肌肉—手指系统。在手指运动中，一块肌肉同时驱动多个手指，多块肌肉同时驱动一个手指。因此，本研究聚焦于手部的肌肉协同与耦合。本文有两个主要贡献：（1）有关手部的发现有助于假肢手的设计；（2）关系谱使在线模型可读，从而统一了在线性能和离线结果。开源代码见https://github.com/liugang1234567/Gang-neuron。

关键词：泰勒级数；关系谱；树突网络；假肢手；机器学习；工程

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Rapid and long-effective removal of broad-spectrum pollutants from aqueous system by ZVI/oxidants

Sana Ullah, Xuejun Guo, Xiaoyan Luo, Xiangyuan Zhang, Siwen Leng, Na Ma, Palwasha Faiz

《环境科学与工程前沿（英文）》 2020年第14卷第5期 doi: 10.1007/s11783-020-1268-3

摘要： Abstract • The coupling of oxidants with ZVI overcome the impedance of ZVI passive layer. • ZVI/oxidants system achieved fast and long-effective removal of contaminants. • Multiple mechanisms are involved in contaminants removal by ZVI/oxidant system. • ZVI/Oxidants did not change the reducing property of ORP in the fixed-bed system. Zero-valent iron (ZVI) technology has recently gained significant interest in the efficient sequestration of a wide variety of contaminants. However, surface passivation of ZVI because of its intrinsic passive layer would lead to the inferior reactivity of ZVI and its lower efficacy in contaminant removal. Therefore, to activate the ZVI surface cheaply, continuously, and efficiently is an important challenge that ZVI technology must overcome before its wide-scale application. To date, several physical and chemical approaches have been extensively applied to increase the reactivity of the ZVI surface toward the elimination of broad-spectrum pollutants. Nevertheless, these techniques have several limitations such as low efficacy, narrow working pH, eco-toxicity, and high installation cost. The objective of this mini-review paper is to identify the critical role of oxygen in determining the reactivity of ZVI toward contaminant removal. Subsequently, the effect of three typical oxidants (H2O2, KMnO4, and NaClO) on broad-spectrum contaminants removal by ZVI has been documented and discussed. The reaction mechanism and sequestration efficacies of the ZVI/oxidant system were evaluated and reviewed. The technical basis of the ZVI/oxidant approach is based on the half-reaction of the cathodic reduction of the oxidants. The oxidants commonly used in the water treatment industry, i.e., NaClO, O3, and H2O2, can be served as an ideal coupling electron receptor. With the combination of these oxidants, the surface corrosion of ZVI can be continuously driven. The ZVI/oxidants technology has been compared with other conventional technologies and conclusions have been drawn.

关键词： Zero-Valent Iron (ZVI) Oxidants Heavy Metals (HMs) Metalloids Nitrate Phosphate

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Ultrathin microcrystalline hydrogenated Si/Ge alloyed tandem solar cells towards full solar spectrum

Yu Cao, Xinyun Zhu, Xingyu Tong, Jing Zhou, Jian Ni, Jianjun Zhang, Jinbo Pang

《化学科学与工程前沿（英文）》 2020年第14卷第6期页码 997-1005 doi: 10.1007/s11705-019-1906-0

摘要： Thin film solar cells have been proved the next generation photovoltaic devices due to their low cost, less material consumption and easy mass production. Among them, micro-crystalline Si and Ge based thin film solar cells have advantages of high efficiency and ultrathin absorber layers. Yet individual junction devices are limited in photoelectric conversion efficiency because of the restricted solar spectrum range for its specific absorber. In this work, we designed and simulated a multi-junction solar cell with its four sub-cells selectively absorbing the full solar spectrum including the ultraviolet, green, red as well as near infrared range, respectively. By tuning the Ge content, the record efficiency of 24.80% has been realized with the typical quadruple junction structure of a-Si:H/a-Si Ge :H/µc-Si:H/µc-Si Ge :H. To further reduce the material cost, thickness dependent device performances have been conducted. It can be found that the design of total thickness of 4 m is the optimal device design in balancing the thickness and the . While the design of ultrathin quadruple junction device with total thickness of 2 m is the optimized device design regarding cost and long-term stability with a little bit more reduction in . These results indicated that our solar cells combine the advantages of low cost and high stability. Our work may provide a general guidance rule of utilizing the full solar spectrum for developing high efficiency and ultrathin multi-junction solar cells.

关键词： thin films solar cells quadruple junction solar cell amorphous silicon silicon germanium alloy quantum efficiency

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Multifractal characteristics of cylindrical sludge drying

Weiyun WANG, Aimin LI,

《环境科学与工程前沿（英文）》 2009年第3卷第4期页码 464-469 doi: 10.1007/s11783-009-0040-5

摘要： This paper analyzes dewatered sludge drying using the multifractal theory. The drying rates of cylindrical sludge with equal masses but different cross-sectional diameters was studied, from which multifractal parameters such as partition function and quality exponent were obtained. The parameters acquired were used to calculate the multifractal singularity spectrum and indicate the presence of multifractal characteristics. The smaller cross-sectional diameters of the sludge were found to be non-homogeneous, and required quantitative methods to analyze.

关键词： multifractal characteristic multifractal singularity spectrum sewage sludge drying

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标题作者时间类型操作

Mirror system based therapy for autism spectrum disorders

CHEN Wei, ZHANG Jing, DING Jun

期刊论文

Solar fuel from photo-thermal catalytic reactions with spectrum-selectivity: a review

Sanli TANG, Jie SUN, Hui HONG, Qibin LIU

期刊论文

Detection of geosmin and 2-methylisoborneol by liquid-liquid extraction-gas chromatograph mass spectrum(LLE-GCMS) and solid phase extraction-gas chromatograph mass spectrum (SPE-GCMS)

MA Xiaoyan, CHEN Beibei, LI Qingsong, ZHANG Qiaoli, GU Guofen

期刊论文

Contact fatigue life prediction of a bevel gear under spectrum loading

Pan JIA, Huaiju LIU, Caichao ZHU, Wei WU, Guocheng LU

期刊论文

一种新的通信抗干扰技术体制：预编码跳码扩谱

姚富强,张毅

期刊论文

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

密码函数的一类递归构造方法