Logical Image Acquisition and Analysis of Android Smartphones

Android smartphones largely dominate the smartphone market. For this reason, it is very important to examine these smartphones in terms of digital forensics since they are often used as evidence in trials. It is possible to acquire a physical or logical image of these devices. Acquiring physical and logical images has advantages and disadvantages compared to each other. Creating the logical image is done at the file system level. Analysis can be made on this logical image. Both logical image acquisition and analysis of the image can be done by software tools. In this study, the differences between logical image and physical image acquisition in Android smartphones, their advantages and disadvantages compared to each other, the difficulties that may be encountered in obtaining physical images, which type of image contributes to obtaining more useful and effective data, which one should be preferred for different conditions, and the benefits of having root authority are discussed. The practice of getting the logical image of the Android smartphones and making an analysis on the image is also included. Although root privileges are not required for logical image acquisition, it has been observed that very limited data will be obtained with the logical image created without root privileges. Nevertheless, logical image acquisition has advantages too against physical image acquisition.

A DATA ACQUISITION SYSTEM FOR ACCELERATOR MASS SPECTROMETRY

A single and dual parameter data acquisition, ion beam measurements and control system for accelerator mass spectrometry is described. The system hardware has been constructed with the advantage of the lower cost and higher reliability. It is provided with varieties of functions such as selecting acquisition mode carrying out the multiple display, analyzing data and especially viewing isometric spectrum at different directions. It can also be used for ordinary nuclear spectrum system.

Integration system research and development for three-dimensional laser scanning information visualization in goaf

An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable.

Discuss on High Speed Data Acquisition and Signal Processing

In order to realize the high speed data acquisition and fast Fourier analysis, the paper put forward a kind of high speed data acquisition and analysis system based on FPGA, the system uses Cyclone series FPGA with high-speed A/D converter, and use the fast Fourier custom analysis nucleation of Altera company, using the standard TCP/IP protocol communication with PC, match up the master machine based on Matlab GUI analysis software. We experiment high speed data acquisition and fast Fourier analysis for a plurality of groups of high frequency analog signals, at the same time the results display on the computer. The experimental results validate the fast Fourier analysis theory, and has realized the low cost, high performance data acquisition and analysis of the complete system design.

MODEL MEASUREMENT AND ANALYSIS OF ROTOR BEARING SYSTEM OF OE-SPINNING

This paper describes a CAD compatible software which can conduct model measurementand analysis on a dedicated computer system.This system which can provide modal testing andanalysis capability is also demonstrated briefly.It addresses four main tasks:(1)modal testingand data acquisition,(2)data analysis and correlation,(3)output of modal analysis results,(4)predictions of modal parameters using Structural Dynamic Modification (SDM)software.

Design and validation of wireless strain test system for bridge based on the resistance strain sensor

In order to achieve an access to strain sensor data with wireless transmission in bridge engineering structure testing, a wireless strain test system is presented based on the resistance strain sensor of networks. The wireless bridge strain test system composed of master station and substation adopts the wireless method to realize the high accuracy data acquisition between the master station and the substation under a reliable communication protocol. The system has been tested in contrast with the present strain apparatus. Results show that the wireless system is high-reliable, and has many characteristics such as high efficiency, good precision, high stability with low cost, and good flexibility, without using the present communication network.

Three-axis magnetic flux leakage in-line inspection simulation based on finite-element analysis

With the increase of pipelines, corrosion leakage accidents happen frequently. Therefore, nondestructive testing technology is important for ensuring the safe operation of the pipelines and energy mining. In this paper, the structure and principle of magnetic flux leakage （MFL） in-line inspection system is introduced first. Besides, a mathematic model of the system according to the ampere circuit rule, flux continuity theorem, and column coordinate transform is built, and the magnetic flux density in every point of space is calculated based on the theory of finite element analysis. Then we analyze and design the disposition of measurement section probes and sensors combining both three-axis MFL in-line inspection and multi-sensor fusion technology. Its advantage is that the three-axis changes of magnetic flux leakage field are measured by the multi-probes at the same time, so we can determine various defects accurately. Finally, the theory of finite element analysis is used to build a finite element simulation model, and the relationship between defects and MFL inspection signals is studied. Simulation and experiment results verify that the method not only enhances the detection ability to different types of defects but also improves the precision and reliability of the inspection system.

Mergers and Acquisitions: An Efficiency Evaluation

This article sheds light on how synergies arise through mergers and acquisitions (M&A). Enterprises go through the process of Mergers and Acquisitions (M&A) with the goal of improving performance, increasing efficiency and obtaining business synergy. Prior literature suggests that synergies could arise due to taxes, market power or efficiency improvements. This study evaluates the efficiency of M&A in Brazil among publicly-traded companies. We used models with multiple objectives from Goal Programming and Data Envelopment Analysis (GPDEA), employing accounting indicators as input and output variables, and thus evaluated the emergence of synergy gains. These models allow us to analyze and classify the M&A according to the efficiency obtained in such processes. Some of the M&A cases analyzed were mistakenly considered efficient when used traditional models. And, as expected, the GPDEA was proved to be superior to classical models;however it was noticed that few of the cases investigated were proved to be effective. We presented a new application for multi-objective approach that can be used to assess mergers and acquisitions. The dualapplication of GPDEA provided a greater understanding of efficiency generation in synergy creation by means of M&A.

Research of CRP-based irregular 2D seismic acquisition

Seismic exploration in the mountainous areas of western Chinese is extremely difficult because of the complexity of the surface and subsurface, which results in shooting difficulties, seismic data with low signal-to-noise ratio, and strong interference. The complexity of the subsurface structure leads to strong scattering of the refl ection points; thus, the curved-line acquisition method has been used. However, the actual subsurface structural characteristics have been rarely considered. We propose a design method for irregular acquisition based on common refl ection points（CRP） to avoid difficult-to-shoot areas, while considering the structural characteristics and CRP positions and optimizing the surfacereceiving line position. We arrange the positions of the receiving points to ensure as little dispersion of subsurface CRP as possible to improve the signal-to-noise ratio of the seismic data. We verify the applicability of the method using actual data from a site in Sichuan Basin. The proposed method apparently solves the problem of seismic data acquisition and facilitates seismic exploration in structurally complex areas.

船舶操纵性约束模测量系统设计与分析

为解决实验室船舶操纵性约束模实验中的测量及数据分析处理技术问题,开发组建实验测量系统,推导数据分析处理方法,以期实现约束模实验的测量与数据在线分析处理;根据前期研究经验,设计了较为完善的测量硬件系统方案;为实现约束模中精确的零相位整周期测量要求,采用光电开关利用数据采集卡的硬件触发启动功能,并给出了整数周期测量的方案;利用最小二乘拟合及傅里叶分析等方法推导给出各船舶水动力导数数据处理方法;在此基础上,作为重点编写了完整的在线测量与数据在线分析程序,主要功能内部独立实现;该系统手工介入频度低,基本实现了测量的自动化,效率得到大幅提高;最后进行实际测量验证,数据的拟合结果与测量结果符合良好,验证了该系统的可靠性;同时处理结果显示船舶附加质量导数Y同船舶惯性质量很接近,而导数Y′r,N′数值很小,近于零。

基于证据链的产品质量检测信息化系统

工业信息化4.0提出以来,对质量检测的可靠性和检测效率的要求不断提高。为解决基于传统的依靠人工加以检测仪器辅助的质量检测手段效率低下、检测结果受人的主观影响较大等问题,文章提出基于数字化证据链的产品质量检测信息化系统,全面介绍了系统的基本架构,包括产品质量检测数据采集模块、过程数据数字化模块、数据分析管理模块、过程检验动态管理模块、证据链构造和解析模块以及客户质量检测数据管理模块,并基于上述模块组成的系统介绍了四种典型的工作流程,给出了相关应用案例,以供各生产、检测人员参考。

大型起重机数字化检测技术开发与研究

拟利用起重机振动检测、无损检测、金属结构在线应力检测、起重机电气控制系统检测、数据库技术、智能分析软件等技术手段,基于起重机基本信息数据、技术参数数据、检验数据、维保数据、物联网设备采集数据等多维度数据,研究出一套针对大型起重机的数字化检测技术,并通过对大数据的分析,制定出有针对性的起重机使用意见、维护保养意见和使用寿命监测意见,从而进一步提高大型起重机的工作效率、降低起重机安全事故的发生频率,为起重机带来更好的使用性能、为操作人员带来安全保障、为企业带来经济效益、为政府带来社会效益。

基于SCADA系统和信号处理的风力发电机主轴承故障分析与诊断

基于SCADA在线监测系统,通过该系统获取到主轴承实时振动数据,用小波包、集合经验模态分解模型进行信号处理和提取故障特征,分析其时域图的冲击信号、频谱图故障特征频率、包络谱故障频率幅值和谐波信号倍数情况,可以判断出主轴承故障位置以及受损情况,实现主轴承故障预警,为风力发电场现场运维人员高效维修提供帮助,降低运维成本。

搭载式动态轨道检查仪数据采集系统研究

及时准确检测轨道几何形位对保证行车安全具有重要意义。搭载式动态轨道检查仪是一种安装于运营列车的新型轨道检测装置,是现有轨道检测方式的补充。搭载式动态轨道检查仪数据采集系统由高精度惯性导航模块、卫星导航模块、轴箱加速度测量系统和非接触式轨距测量系统组成。采集系统采用多线程技术、多传感器时间同步算法以及高精度惯性导航模块加速度修正和基于组合惯性导航系统信息融合的里程定位方法,实现了多源高频运行列车动态响应信息在时空维度上的高一致性。应用表明,轨道检查仪数据采集系统运行稳定、数据完整准确,成果满足轨道几何形位解算的需要。

网络舆情监控及预警系统构建与应用研究

系统采用前后端分离的开发模式,构建了可以实现用户登录、舆情采集、舆情展示、舆情分析四大功能的网络舆情监控及预警系统。该系统利用网络爬虫技术爬取国内舆情排行网站的热点信息,通过关键字检索对网民的评论意见以及发表内容进行全面分析,从而实现网络舆情的动态监测,为用户对网络舆情的干预提供依据。

基于多元增量分析模型的流域电厂大数据采集监视

提出基于多元增量分析模型的流域电厂大数据采集监视方法,通过数据分析发现异常电厂大数据,保障流域电厂安全运行。数据采集层在PIC18F8722单片机控制下利用多种传感器获取采集对象层的多种流域电厂数据,经数据汇集层的弹性消息总线和转发代理,将采集数据传输至数据处理层数据接收模块,多元增量分析模型调用接收到的数据,通过增量的方式构建电厂数据矩阵正常检测模型,对比其与待检测数据,发现异常电厂大数据,并将异常检测结果族谱写入数据存储层数据库所对应的列簇里,通过前端展示层将监视结果呈现给用户。实验结果表明,该方法可精准、快速采集流域电厂海量数据,可有效发现流域电厂的异常数据,并将其可视化呈现,确保流域电厂安全运行。

大数据背景下食品快速检测工作智慧监管模式研究

目的深挖快检数据,构建食品快速检测工作质里评价模型,实现快检工作靶向治理与智慧监管。方法基于海量快检数据,对农贸市场食品快检工作现状及监管模式进行分析,构建食品快速检测工作质量评价模型。结果通过开展食品快检大数据系统研究,提高快检工作评价的科学性和实效性。结论为实现快检工作的精准监管、智慧监管,以及基层监管的有的放矢提供了理论依据和实践指导。

V2G直流充电桩检测方案与检测系统设计

针对现有V2G直流充电桩现场检测装置功能不全面、检测方案单一、控制及管理困难等问题,依据国家相关标准,设计了V2G直流充电桩检测方案和检测系统。首先,根据需要设计了3种检测方案:现场检测方案、实验室检测方案以及动力电池检测方案。不同的检测方案对应V2G充电桩不同检测环境和检测项目。然后,依据3种检测方案给出了检测系统的硬件设计和软件设计,能够实现对V2G直流充电桩充放电功能、直流输出性能、并网性能及保护功能等进行检测。同时还可以对电动汽车动力电池状态进行评估,从而判断电池潜在风险。最后,通过对V2G直流充电桩和车辆动力电池进行不同项目检测。测试结果表明所设计的检测方案和检测系统能够准确实现对V2G直流充电桩的功能和性能检测。

基于智能运维数据的轮对维护方法研究

为研究智能运维设备采集数据对轮对维护方法的优化,本文重点分析了轮对尺寸与廓形数据的预处理方法,分析线路的车轮磨耗特征,为轮对维护提供建议,提出适用于研究线路的镟修周期优化方法。通过对智能运维设备采集的轮对数据应用方向的分析,采用滤波修正和弦高筛选法对2017—2020年上海地铁实测数据进行预处理,根据不同镟修模板呈现的变化特征具体分析并给出措施,最后建立以镟修模板为区分的轮缘分段磨耗模型,输出了列车级车轮镟修周期优化策略。研究结果表明:通过智能运维设备采集的轮对数据信息较人工测量数据效率显著提高,且能够直观区分踏面与轮缘异常磨耗特征,镟修周期的优化相较于传统尺寸超限镟修方式,更符合实际线路磨耗规律。

网络版过程数据采集与分析软件的研究和应用

为提高变频器产品调试和故障监控分析能力,提出了网络版过程数据采集与分析软件设计方案,论述了软件系统的组成以及实现方式,提出了多线程、虚拟内存、绘图类库、高速光纤同步等技术手段用以解决系统运行技术难题。此软件系统经过现场应用表明,系统运行稳定,具有低成本、多通道传输、低采样周期、高数据精度、图形功能丰富、可扩展性强等特点。