基于虚拟仪器的振动信号采集分析系统

以PC机、数据采集板为主要硬件，以图形化编程语言LabVIEW为软件开发平台，设计并实现了振动信号采集分析虚拟仪器系统。对该系统平稳和非平稳振动信号的采集、处理和分析各功能模块进行了具体介绍，并以信号发生器产生的噪声、三角波与正弦波混合波形为例，重点分析了非平稳信号的处理——小波分析的实现过程。     

基于小波变换的轧辊磨床振动信号分析

针对实际测试项目,介绍用于轧辊磨床振动测量的信号采集系统的硬件组成及信号采集方法.简述振动信号分析的理论与方法,采用基于小波变换的信号分析方法对磨床振动信号进行分析,能同时兼顾高频与低频段的频谱特性,提高特征频率的提取精确度,进而提高系统故障诊断的可靠性.     

DAS—1动态信号分析与故障诊断系统的功能和特点

DAS-1动态信号分析与故障诊断系统是在对“CDMS信号处理故障诊断及振动分析系统”(见本刊1991年第9期第20页—编注)作了大规模改进的基础上研制而成的新一代全彩色汉化系统。系统由微机(台式或便携式)、A/D板、接口箱、打印机及DAS-1软件包组成,其功能包括转速定常监测、信号监测与采集、信号处理、瞬态分析、故障诊断、     

电涡流传感器测振失效常见问题处理

分析现场发生的几种非转子真实振动的电涡流传感器振动信号,说明其原因和处理方法。     

风电机组齿轮箱故障评价方法研究现状

风电齿轮箱故障评价方法主要有传统故障评价方法、基于数学建模的故障评价方法和基于数据挖掘的智能故障评价方法。分析国内外在风电齿轮箱故障评价方法以及状态监测系统的研究现状,指出人工神经网络技术、专家系统和小波技术等的发展将会使齿轮箱故障评价方法的研究逐步趋于智能化方向发展,同时能够完善现有的齿轮箱状态监测系统。可以将振动信号、温度信号和金属颗粒信号融合,开发新的风电机组齿轮箱状态监测与故障评价系统。     

内燃机气门故障的时频对比分析

通过对比分析内燃机气门在间隙偏大和漏气故障时振动和超声波信号的时频特征，探寻对内燃机气门故障敏感的信号类型和处理方法。     

经验模态分解在切削振动信号分析中的应用

为了分析切削振动的变化规律及产生根源,采用在线监测的方法采集振动信号,提出了运用经验模态分解对振动信号进行分析的方法,构建了分段频率变化的仿真振动信号,分别对仿真振动信号进行短时傅里叶变换、小波变换和经验模态分解时频分析。结果表明,经验模态分解方法具有更高的时频分辨率,运用经验模态分解方法对实际振动信号进行分析,提取典型分量绘制希尔伯特幅值谱,能较好地反映振动信号的时频变化规律。经验模态分解适合对切削振动信号进行分析,但是需要对算法的模态混叠及计算效率低等不足进行完善。研究结果对非平稳信号的分析具有参考价值。     

电磁式油液金属磨粒检测系统研究

通过检测润滑油中磨损金属颗粒的数量和尺寸信息,能够反映机械设备的磨损故障程度。电磁式螺旋差动传感器是检测油液磨粒信息的一种重要方法,具有结构简单、响应快、外界振动干扰小、不被气泡影响、区别金属性质等优点。针对电磁式颗粒探测的难点,分析励磁磁场和感应电动势的数学模型,设计了差动式螺旋电磁传感器的结构。采用直接数字频率合成方法产生激励信号,基于单片机设计具有锁相分析的信号检测硬件系统。系统能够检测最小100μm的磨损金属颗粒。     

基于振动与电流的感应电机轴承故障诊断系统

根据感应电机轴承故障振动信号与定子电流信号的特点,以LabVIEW为开发平台,设计一种基于振动信号和定子电流信号的多传感器融合电机轴承故障检测系统,实现电机运行过程中轴承振动与电流信号的同步在线检测。     

公路工程振动压路机液压故障及维护技术

振动压路机液压系统的故障诊断和维护是公路工程中非常重要的一项技术。分析介绍振动压路机液压系统行走系统和振动系统的液压原理、故障现象和诊断处理方法,提出维护保养措施,以确保振动压路机的正常运行,提高设备的工作效率,提高公路工程整体施工质量。     

继电器试验中高频信号采集技术的研究

介绍了数据采集系统的工作原理,对系统中各个环节的参数进行了分析计算。以DSP为核心组成了高速数据采集系统板,充分利用易扩展的优点,继电器分析电路时产生的过电压信号进行采集,应用当时的数字信号处理知识,数字滤波及快速傅立叶变换,对所采集的信号进行幅值与频率的分析与处理,并与记忆示波器所测得的波形进行验证比较,得出实际的过电压波形。     

基于DSP的电机断条故障在线检测系统设计

针对传统以单片机为核心的电机断条故障在线检测系统计算能力有限,不能实时、有效地进行高速数据处理的缺点,结合数字信号处理器DSP的高精度、高速率的特点,研制了以TMS320F2812为核心的电机断条故障在线检测系统,该系统可以实时采集电机的电流、电压、转速等参数,实时处理采集到的电机数据,在线监测电机状态,系统通过细化包络算法诊断电机断条故障,当有故障出现时发出报警信号,并以自动短信方式通知值班人员,从而保证电机正常运行。     

Industrial marketing management digital media optimization for B2B marketing

The role of digital media in B2B marketing has gained traction with academics and practitioners in recent years. However, a comprehensive framework about the use and value of these media has not been developed, leaving B2B experts uncertain about their effectiveness. In fact, whether or not digital media can impact the business development and marketing processes to achieve higher performance remains vague. Additionally, there is a paucity of research related to the impact of different media towards the enhancement of processes and outcome of marketing to generate opportunities. To provide guidance for practitioners, we consider marketing processes in the global software industry by researching practitioner experiences. We develop an assessment tool to identify and align marketing processes and digital media. This research attempts to explore and explain how digital media impacts the B2B business development process cycle at the conjunction of marketing and sales. The research tests a conceptual model by means of a cross-sectional survey of more than 530 practitioners. Our novel framework provides several contributions to knowledge and practice, defining marketing-related processes, and determining a set of digital platforms. By acknowledging the perspectives of vendors, third-parties, and buyers in a simultaneous study, we ensure optimal alignment.     

基于印能捷流程的数据流控制模板的建立

现代印刷生产在数字化信息处理和计算机控制技术的推动下,正在采用数字化生产流程进行印刷产业的新变革。印刷数字化工作流程不仅通过印刷图文信息、的数字化改变了传统印前、印刷工艺的面貌,而且通过数字化的图文信息数据流控制,改变了传统印刷生产的信息组织与传递,为印刷工业发展带来新的机遇与挑战。本文以印能捷数字化工作流程为基础,重点研究数字化印前流程中数据流的控制方法,并根据实际生产要求,采用理论分析和实验验证相结合的方式,通过设置各种不同格式及内容的文件,解析了数据流传递与控制的关键节点、参数设置与优化,建立了一套模式化的、简单易用的数据流控制模板,实现了印刷数据流在整个印前流程中准确顺畅的传递。研究成果对印刷企业应用数字化生产流程提升印刷质量,提高生产效率具有很好的理论指导作用和实际应用价值。     

齿轮故障的频域诊断

本文介绍了齿轮故障的频域诊断方法。该方法是通过对测取齿轮工况下的振动信号进行频谱分析,从而找出齿轮产生故障的原因。     

Digital servitization: Crossing the perspectives of digitization and servitization

For over three decades now, several product companies around the world have been undertaking servitization paths. They have been devoting growing and substantial efforts to expand their service business. Expanding the service business in addition to their traditional core product business secures long-term growth and strengthens competitive advantages in business-to-business marketplaces. Recently, service business expansion has taken up many of the new digital technologies offered through the digital transformation. Thus, the servitization literature has progressed toward a dialogue on digital servitization . Against this background, the present article introduces the reader to this special issue. It first recalls key aspects of the emerging digital servitization discussion, and then depicts, through illustrative case studies, the growth paths utilized by industrial product companies when they take advantage of the digital servitization process. After discussing how the articles included in this special issue advance the literature, the article develops a number of directions for future research on digital servitization.     

滚动轴承故障的波谱分析

本文首先对典型故障滚动轴承的振动信号特征作了理论分析。并对试验测得的振动信号进行了波形与频谱分析。包括时域与幅值域中的时间历程、概率密度函数与自相关分析;频域中的功率谱与倒频谱分析。寻找到各类故障轴承在波谱方面的规律特征,并依此对生产中振动噪声不合格的滚动轴承进行故障部位与性质的诊断,取得了一致的结论。     

The role of digital technologies in open innovation processes: an exploratory multiple case study analysis

Digital transformation has undoubtedly become a key enabler of innovation as evidenced by the numerous firms that use digital technologies to manage their innovation processes. This issue is even more relevant today when innovation processes have become more open and require greater resources in the different implementation phases to capture and transfer knowledge within and outside the firm's boundaries. This implies additional challenges in managing the increasing amount of knowledge and information flows. Accordingly, digital technologies can be used and implemented to manage open innovation processes through easier access and sharing the knowledge created and transferred. Nevertheless, literature in these fields does not provide a structured view of how and why digital technologies are used to manage innovation processes in an open perspective. This paper aims to bridge this gap by adopting the theoretical lenses of change management to identify the managerial actions at organizational and process level that companies perform to implement digital technologies in their open innovation processes. Accordingly, the paper investigates how and why these managerial actions required for and enabled by digital technologies help firms to develop and nurture open innovation. From an empirical point of view, the exploratory multiple case study analyzes nine firms operating in different industries and varying in size, market share, and organizational structure.     

AI governance in the public sector: Three tales from the frontiers of automated decision-making in democratic settings

The rush to understand new socio-economic contexts created by the wide adoption of AI is justified by its far-ranging consequences, spanning almost every walk of life. Yet, the public sector's predicament is a tragic double bind: its obligations to protect citizens from potential algorithmic harms are at odds with the temptation to increase its own efficiency - or in other words - to govern algorithms, while governing by algorithms. Whether such dual role is even possible, has been a matter of debate, the challenge stemming from algorithms' intrinsic properties, that make them distinct from other digital solutions, long embraced by the governments, create externalities that rule-based programming lacks. As the pressures to deploy automated decision making systems in the public sector become prevalent, this paper aims to examine how the use of AI in the public sector in relation to existing data governance regimes and national regulatory practices can be intensifying existing power asymmetries. To this end, investigating the legal and policy instruments associated with the use of AI for strenghtening the immigration process control system in Canada; “optimising” the employment services” in Poland, and personalising the digital service experience in Finland, the paper advocates for the need of a common framework to evaluate the potential impact of the use of AI in the public sector. In this regard, it discusses the specific effects of automated decision support systems on public services and the growing expectations for governments to play a more prevalent role in the digital society and to ensure that the potential of technology is harnessed, while negative effects are controlled and possibly avoided. This is of particular importance in light of the current COVID-19 emergency crisis where AI and the underpinning regulatory framework of data ecosystems, have become crucial policy issues as more and more innovations are based on large scale data collections from digital devices, and the real-time accessibility of information and services, contact and relationships between institutions and citizens could strengthen – or undermine - trust in governance systems and democracy.