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临震信号 3

信息处理 3

发展战略 2

振动信号 2

材料 2

AD9954 1

AR模型 1

BPSK 1

CCS 1

CO₂分离 1

CPU-GPU异构；多核；共享内存；访存调度 1

DPP）；分布式功率转换器；开关电容转换器 1

GPU；密度峰值；聚类；并行计算 1

Kripke结构 1

MPPT）；差分功率处理（Differential power processing 1

MSJPDA 1

MapReduce；近似作业；时限；任务调度；掉队任务消除 1

RBF神经网络 1

SAA7121 1

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自适应小波阈值去噪在重力仪信号处理中的应用

赵立业,周百令,李坤宇

《中国工程科学》 2006年第8卷第3期页码 49-52

摘要：

为了有效地消除各种外界干扰噪声对高精度海洋重力仪测量值的影响，提高重力异常测量值的精度，在分析了小波阈值及自适应小波阈值去噪算法的基础上，将其应用到高精度海洋重力仪系统数据处理中，并与自适应卡尔曼滤波做了对比，以处理后信号的信噪比作为衡量3种数据处理方法优劣的依据。理论分析和仿真实验表明，自适应小波阈值去噪方法、传统的小波阈值去噪方法和自适应卡尔曼滤波都能在一定程度上消除噪声信号对重力仪测量信号的影响，但在相同情况下，自适应小波阈值去噪方法具有明显的优越性。

关键词：重力仪信号处理小波变换自适应阈值去噪自适应卡尔曼滤波

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Gear fault diagnosis using gear meshing stiffness identified by gearbox housing vibration signals

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0713-3

摘要： Gearbox fault diagnosis based on vibration sensing has drawn much attention for a long time. For highly integrated complicated mechanical systems, the intercoupling of structure transfer paths results in a great reduction or even change of signal characteristics during the process of original vibration transmission. Therefore, using gearbox housing vibration signal to identify gear meshing excitation signal is of great significance to eliminate the influence of structure transfer paths, but accompanied by huge scientific challenges. This paper establishes an analytical mathematical description of the whole transfer process from gear meshing excitation to housing vibration. The gear meshing stiffness (GMS) identification approach is proposed by using housing vibration signals for two stages of inversion based on the mathematical description. Specifically, the linear system equations of transfer path analysis are first inverted to identify the bearing dynamic forces. Then the dynamic differential equations are inverted to identify the GMS. Numerical simulation and experimental results demonstrate the proposed method can realize gear fault diagnosis better than the original housing vibration signal and has the potential to be generalized to other speeds and loads. Some interesting properties are discovered in the identified GMS spectra, and the results also validate the rationality of using meshing stiffness to describe the actual gear meshing process. The identified GMS has a clear physical meaning and is thus very useful for fault diagnosis of the complicated equipment.

关键词： gearbox fault diagnosis meshing stiffness identification transfer path signal processing

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Basic research on machinery fault diagnostics: Past, present, and future trends

Xuefeng CHEN, Shibin WANG, Baijie QIAO, Qiang CHEN

《机械工程前沿（英文）》 2018年第13卷第2期页码 264-291 doi: 10.1007/s11465-018-0472-3

摘要：

Machinery fault diagnosis has progressed over the past decades with the evolution of machineries in terms of complexity and scale. High-value machineries require condition monitoring and fault diagnosis to guarantee their designed functions and performance throughout their lifetime. Research on machinery Fault diagnostics has grown rapidly in recent years. This paper attempts to summarize and review the recent R&D trends in the basic research field of machinery fault diagnosis in terms of four main aspects: Fault mechanism, sensor technique and signal acquisition, signal processing, and intelligent diagnostics. The review discusses the special contributions of Chinese scholars to machinery fault diagnostics. On the basis of the review of basic theory of machinery fault diagnosis and its practical applications in engineering, the paper concludes with a brief discussion on the future trends and challenges in machinery fault diagnosis.

关键词： fault diagnosis fault mechanism feature extraction signal processing intelligent diagnostics

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自适应BPSK解调方法研究

李炎新,胡爱群,宋宇波

《中国工程科学》 2006年第8卷第5期页码 49-51

摘要：

提出了一种新型的基于自适应滤波算法的解调二进制相移键控（BPSK）信号的方法。以常用的最小均方误差自适应算法（LMS）为例，讨论了新型的BPSK自适应解调的过程及其性能。该解调算法不需要自适应滤波器完成收敛，从而降低了采样频率。给出的理论性能与仿真结果表明，BPSK自适应解调的误码率仿真结果与理论值吻合非常好；而且该方法具有抗干扰性能强、输出响应快、便于数字信号处理（DSP）技术实现等特点，在相同的采样频率下其误码率优于相关解调的误码率。

关键词：数字通信自适应信号处理解调 BPSK

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一般四元数函数梯度的定义、特性及在信号处理领域的应用

Meng-di Jiang, Yi Li, Wei Liu,w.liu@sheffield.ac.uk

《信息与电子工程前沿（英文）》 2016年第17卷第2期页码 83-95 doi: 10.1631/FITEE.1500334

摘要：目的：随着四元数在信号处理各个领域越来越广泛的应用，基于四元数的信号处理理论也获得了快速发展。然而，制约其进一步应用的一个瓶颈就是对一般四元数函数的梯度的定义及特性还缺乏清晰并有说服力的描述。本文就试图对这一问题进行探索。创新点：在信号处理中，虽然很多优化函数的值都是实数，但在进行优化时，尤其是在非线性信号处理中，经常会遇到对取值为四元数的四元数函数求梯度。不同于以往只适用于实数值四元数函数梯度的定义，本文第一次就一般四元数函数的梯度给出了一个自洽的定义，并对其特性进行了详细的研究和描述。基于以上研究，本文对四元数值的最小均方(LMS)自适应算法，以及一个有代表性的非线性自适应算法进行了推导，并以矢量传感器阵列波束形成为例进行了计算机模拟。

关键词：四元数；梯度；信号处理；最小均方算法；非线性自适应滤波；波束形成

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提高硅微谐振系统性能的一项有效措施

夏敦柱,王寿荣,周百令

《中国工程科学》 2006年第8卷第10期页码 71-74

摘要：

介绍了硅微谐振器系统的工作原理，重点给出了一种基于新型的DDS器件AD9954的智能谐振系统设计与实现。详细分析了AD9954作为智能精密驱动源的粗细搜索两种阶段工作流程并给出与DSP器件的数字接口技术。结合实验数据和扫频曲线，得出在不同真空度环境下谐振器的两种扫频结果，并对谐振系统的工作情况给予评价。

关键词：直接数字合成(DDS) 硅微谐振器 AD9954 数字信号处理(DSP)

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Review on flexible perovskite photodetector: processing and applications

《机械工程前沿（英文）》 2023年第18卷第2期 doi: 10.1007/s11465-023-0749-z

摘要： Next-generation optoelectronics should possess lightweight and flexible characteristics, thus conforming to various types of surfaces or human skins for portable and wearable applications. Flexible photodetectors as fundamental devices have been receiving increasing attention owing to their potential applications in artificial intelligence, aerospace industry, and wise information technology of 120, among which perovskite is a promising candidate as the light-harvesting material for its outstanding optical and electrical properties, remarkable mechanical flexibility, low-cost and low-temperature processing methods. To date, most of the reports have demonstrated the fabrication methods of the perovskite materials, materials engineering, applications in solar cells, light-emitting diodes, lasers, and photodetectors, strategies for device performance enhancement, few can be seen with a focus on the processing strategies of perovskite-based flexible photodetectors, which we will give a comprehensive summary, herein. To begin with, a brief introduction to the fabrication methods of perovskite (solution and vapor-based methods), device configurations (photovoltaic, photoconductor, and phototransistor), and performance parameters of the perovskite-based photodetectors are first arranged. Emphatically, processing strategies for photodetectors are presented following, including flexible substrates (i.e., polymer, carbon cloth, fiber, paper, etc.), soft electrodes (i.e., metal-based conductive networks, carbon-based conductive materials, and two-dimensional (2D) conductive materials, etc.), conformal encapsulation (single-layer and multilayer stacked encapsulation), low-dimensional perovskites (0D, 1D, and 2D nanostructures), and elaborate device structures. Typical applications of perovskite-based flexible photodetectors such as optical communication, image sensing, and health monitoring are further exhibited to learn the flexible photodetectors on a deeper level. Challenges and future research directions of perovskite-based flexible photodetectors are proposed in the end. The purpose of this review is not only to shed light on the basic design principle of flexible photodetectors, but also to serve as the roadmap for further developments of flexible photodetectors and exploring their applications in the fields of industrial manufacturing, human life, and health care.

关键词： photodetector perovskite flexible processing application

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CHARACTERISTICS OF HERBIVORY/WOUND-ELICITED ELECTRICAL SIGNAL TRANSDUCTION IN TOMATO

《农业科学与工程前沿（英文）》 2021年第8卷第2期

摘要：

Electrical signals commonly occur in plants in response to various environmental changes and have a dominant function in plant acclimation. The transduction of wound-elicited electrical signals in the model plant species Arabidopsis has been characterized but the characteristics of electrical signal transduction in response to herbivory or wounding in crop species remain unknown. Here, the features of electrical signals elicited by insect herbivory and wounding in tomato were investigated. Unlike those in Arabidopsis, wounding tomato leaves did not cause leaf-to-leaf electrical signal transduction. In contrast, electrical signals elicited in response to petiole wounding were stronger and more strongly transduced. Leaflet wounding also activated electrical signal transduction and jasmonic acid (JA) signaling within the whole compound leaf. It was also demonstrated that tomato glutamate receptor-like 3.3 (GLR3.3) and GLR3.5 mediated leaflet-to-leaflet electrical signal transduction. Herbivory-induced JA accumulation and Helicoverpa armigera resistance were reduced in glr3.3/3.5 plants. This work reveals the nature of electrical signal transduction in tomato and emphasizes the key roles of GLR3.3 and GLR3.5 in electrical signal transduction and JA signaling activation.

关键词： electrical signal / glutamate receptor-like / herbivory / jasmonic acid / tomato

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Acoustic fault signal extraction via the line-defect phononic crystals

《机械工程前沿（英文）》 2022年第17卷第1期页码 10-10 doi: 10.1007/s11465-021-0666-y

摘要： Rotating machine fault signal extraction becomes increasingly important in practical engineering applications. However, fault signals with low signal-to-noise ratios (SNRs) are difficult to extract, especially at the early stage of fault diagnosis. In this paper, 2D line-defect phononic crystals (PCs) consisting of periodic acrylic tubes with slit are proposed for weak signal detection. The defect band, namely, the formed resonance band of line-defect PCs enables the incident acoustic wave at the resonance frequency to be trapped and enhanced at the resonance cavity. The noise can be filtered by the band gap. As a result, fault signals with high SNRs can be obtained for fault feature extraction. The effectiveness of weak harmonic and periodic impulse signal detection via line-defect PCs are investigated in numerical and experimental studies. All the numerical and experimental results indicate that line-defect PCs can be well used for extracting weak harmonic and periodic impulse signals. This work will provide potential for extracting weak signals in many practical engineering applications.

关键词： phononic crystals line-defect fault signal extraction acoustic enhancement

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提高地下金属管振动波测试中冲击响应信号的信噪比

韩修廷,王洁春,焦振强,高飞,宋宇波

《中国工程科学》 2005年第7卷第10期页码 64-68

摘要：

提出了在套损振动波检测过程中提高信号信噪比的方法。检测过程中，在井口敲击套管并接收、分析套管的回波，以了解介质的变化情况。由于反射波信号强度较微弱，单纯用一组接收信号无法进行正确的套损分析，采用信号增强方法，即利用多个类似信号进行叠加，增强反射波的有效信号，降低背景噪声，从而得到有用信息，进行正确的套损状况分析。开发了相应的信号处理软件，提高了信号处理速度。通过10井次的测试表明，技术原理可行，软件工作稳定、可靠，便于操作，可以进行多种方法的信号处理，极大地提高了工作效率。

关键词：振动波反射波信号增强信号叠加

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The role of protein kinase C epsilon in neural signal transduction and neurogenic diseases

null

《医学前沿（英文）》 2011年第5卷第1期页码 70-76 doi: 10.1007/s11684-011-0119-9

摘要：

Protein kinase C epsilon (PKC ?) is one of major isoforms in novel PKC family. Although it has been extensively characterized in the past decade, the role of PKC ? in neuron is still not well understood. Advances in molecular biology have now removed significant barriers to the direct investigation of PKC ? functions in vivo, and PKC ? has been increasingly implicated in the neural biological functions and associated neurogenic diseases. Recent studies have provided important insights into the influence of PKC ? on cortical processing at both the single cell level and network level. These studies provide compelling evidence that PKC ? could regulate distinct aspects of neural signal transduction and suggest that the coordinated actions of a number of molecular signals contribute to the specification and differentiation of PKC ? signal pathway in the developing brain.

关键词： protein kinase C ? signal transduction neurogenic disease

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Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory

Pedro PONCE, Therese PEFFER, Arturo MOLINA

《能源前沿（英文）》 2019年第13卷第3期页码 522-538 doi: 10.1007/s11708-018-0562-2

摘要： It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes; thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (SDT) fuzzy signal detection theory (FSDT) chi-square (CS) test

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Performance prediction of switched reluctance generator with time average and small signal models

Jyoti KOUJALAGI, B. UMAMAHESWARI, R. ARUMUGAM

《能源前沿（英文）》 2013年第7卷第1期页码 56-68 doi: 10.1007/s11708-012-0216-8

摘要： This paper presents the complete mathematical model and predicts the performance of switched reluctance generator with time average and small signal models. The complete mathematical model is developed in three stages. First, a switching model is developed based on quasi-linear inductance profile. Next, based on the switching behaviour, a time average model is obtained to measure the difference between the excitation and generation time in each switching cycle. Finally, to track control voltage and current wave shapes, a small signal model is designed. The effectiveness of the complete multilevel model combining electrical machine, power converter, load and control with programming language is demonstrated through simulations. A PI controller is used for controlling the voltage of the generator. The results presented show that the controller exhibits accurate tracking control of load voltage under different operating conditions. This demonstrates that the proposed model is able to perform an accurate control of the generated output voltage even in transient situations. The simulation is performed to choose the control parameters and study the performance of switched reluctance generator prior to its actual implementation. Initial experimental results are presented using NI-Data acquisition card to control the output power according to load requirements.

关键词： generator reluctance switching model small signal model time average model

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Assessment of popular techniques for co-processing municipal solid waste in Chinese cement kilns

《环境科学与工程前沿（英文）》 2022年第16卷第4期 doi: 10.1007/s11783-021-1485-4

摘要：

• Municipal solid waste (MSW) was fermented, screened, gasified, then co-processed.

关键词： Cement kiln Co-processing Environmental risk assessment By-pass system

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of bradykinin on bradykinin-B2 receptor in rat aortic vascular smooth muscle cells and the involved signal

Wen YAN MD, Min FENG MD, Pei-Hua WANG MD, Dao-Wen WANG MD,

《医学前沿（英文）》 2010年第4卷第2期页码 225-228 doi: 10.1007/s11684-010-0003-z

摘要： The aim of this paper is to study the effect of bradykinin (BK) on bradykinin-B2 receptor as well as the possible involved signal transduction pathways in cultured rat aortic vascular smooth muscle cells (VSMCs). Rat aortic VSMCs were cultured. Cells after 4–6 passages were used in the experiment. VSMCs were incubated with BK, BK+ B2 receptor inhibitor (HOE-140), BK+ MEK inhibitor (PD98059), BK+ mitogen-activated protein kinase (MAPK) inhibitor (apigenin), BK+ phosphoinositide 3-kinase (PI3K) inhibitor (LY294002), and BK+ Akt inhibitor to evaluate the expression of B2 receptor and phosphorylation of signaling molecules MAPK, Akt, and PI3K by Western blot. (1) BK markedly up-regulated the expression of B2 receptor in VSMC. (2) Apigenin, PD98059, Akt inhibitor, and LY294002 inhibited up-regulation of B2 receptor induced by BK. (3) Signal transduction pathways of MAPK and PI3K were involved in the up-regulation of B2 receptor by BK mediation. Results suggest that bradykinin can up-regulate the expression of B2 receptor in VSMCs.

关键词： bradykinin vascular smooth muscle cells signal transduction pathways