基于Unity3D的油田抽油机三维可视化监控系统设计

针对抽油机监测形式单一、三维可视化程度低和联动性差的缺陷,引入信息―物理实时映射思想,开发了油田抽油机三维可视化监控系统。设计了抽油机数字空间,搭建虚实交互层设计架构;搭建三维可视化系统数据组成及关系框架;结合逆运动学,构建数学模型,基于五维模型和Unity 3D平台设计抽油机三维可视化系统总体架构;以游梁式抽油机为对象进行实验验证,实现了实时动态监测、虚实混合控制、运动轨迹追踪和在线预警等服务功能。为三维可视化监控在石油机械领域的落地应用和数字孪生系统的开发提供借鉴。

Assessment of Monitor Units and Gamma Pass Rate for 6 MV and Flattening Filter Free (FFF) Beams in Volumetric Modulated Arc Therapy (VMAT)

Background: In linear accelerators, the treatment field’s uniform intensity is achieved by including a flattening filter in the beam. However, to produce more conformal dose distributions, contemporary radiotherapy practice now frequently uses fluence and aperture modifying techniques, such as volumetric modulated arc therapy. In these circumstances, the flattening filter in the beam manufacturing process is no longer required. It is therefore necessary to compare the monitor units of 6 MV and flattening filter free plans and how it influences the gamma pass rates to determine which is best for treating cervical cancer with pelvic lymph node metastasis. Methods: VMAT plans for fifteen patients with cervical cancer with pathological pelvic lymph node metastasis were included in this study. Each patient had two VMAT plans using conventional 6 MV beam with flattening filter and one with flattening filter free beam (FFF). The VMAT plans were made using two arcs, and then recalculated to give the planned dose distribution to the detectors in a Delta4 phantom. The VMAT plans were irradiated on the Delta4 phantom using an Elekta linear accelerator (6 MV). Results: The mean monitor unit for the 6 MV plans was 506.3 MU and a standard deviation of 48.6 while that of the FFF plans had a mean MU of 701.5 with a standard deviation of 87.6. The total monitor units (MUs) for the FFF plans were significantly greater than the 6 MV plans (p = 6.1 × 10-5). Conclusion: Flattening filter free (FFF) plans require more numbers of monitor units in comparison to conventional 6 MV filtered beams for external radiation of cervical cancer with pelvic lymph nodes involvement.

Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗计划中的应用研究

目的:探讨Varian Eclipse计划系统MU Objective工具在鼻咽癌容积调强放射治疗(VMAT)计划中的应用,旨在保证治疗计划质量的同时降低治疗计划的机器跳数(MU)。方法:选取已接受容积调强放射治疗技术的21例鼻咽癌患者,在未使用MU Objective工具的情况下给每例患者设计治疗参考计划(MU_(ref));将使用MU Objective工具对MU_(ref)进行重新优化,分别设置MU_(ref)的MU的30%、50%、70%、90%和120%,分别命名为MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)。将治疗计划MU_(30%)、MU_(50%)、MU_(70%)、MU_(90%)和MU_(120%)分别与MU_(ref)进行配对t检验统计分析,比较两种治疗计划的靶区、危及器官(OAR)剂量分布和计划的MU。结果:使用MU Objective工具对参考计划优化MU后,与参考计划相比部分靶区和OAR剂量体积参数差异虽有统计学意义,但无临床意义。治疗计划参数为MU_(30%)、MU_(50%)、MU_(70%)和MU_(90%)时,与MU_(ref)比较计划MU平均分别减少21.5%、19.5%、16.6%和8%,差异有统计学意义(t=9.652,t=8.843,t=8.963,t=11.323;P<0.05)。在MU_(120%)时,治疗计划MU平均增加1.7%,但未显著提高靶区剂量覆盖。结论:对于鼻咽癌VMAT计划,使用Eclipse计划系统的MU Objective工具在减少计划MU的同时可获得与参考计划相似的剂量分布。MU Objective工具可作为鼻咽癌或其他部位VMAT计划的常规使用工具,以保证计划质量同时减少放射治疗计划的MU。

Effects of Beam Startup Characteristics on Dose Delivery Accuracy at Low Monitor Units in Step-and-Shoot Intensity Modulated Radiation Therapy

Intensity modulated radiation therapy (IMRT) is a highly accurate technique that is usually implemented in either dynamic or step-and-shoot fashion with many segments each having low monitor units (MUs). The present study evaluated the effects of beam startup characteristics on the dose delivery accuracy for each segment at low MUs for step-and-shoot IMRT with an Elekta Precise accelerator at the highest dose rates. We used a two-dimensional semi-conductor detector for the dose measurements. The field size of each segment was assumed to be 20 ×20 cm2 and each segment was set to deliver 1 - 10 MUs. Our results show a variation in dose delivery accuracy between segments for the same IMRT beam, which can be attributed to the beam startup characteristics. This variability is attributed to the changes in the transient changes in the temperatures of the electron gun filament and the magnetron. That is, the transient increase in the temperature of the filament leads to increasing doses with time and that of the magnetron leads to decreasing doses with time during the first few MUs.

Pros and cons of continuous glucose monitoring in the intensive care unit

Diabetes mellitus affects people worldwide,and management of its acute complications or treatment-related adverse events is particularly important in critically ill patients.Previous reports have confirmed that hyperglycemia can increase the risk of mortality in patients cared in the intensive care unit(ICU).In addition,severe and multiple hypoglycemia increases the risk of mortality when using insulin or intensive antidiabetic therapy.The innovation of continuous glucose monitoring(CGM)may help to alert medical caregivers with regard to the development of hyperglycemia and hypoglycemia,which may decrease the potential complications in patients in the ICU.The major limitation of CGM is the measurement of interstitial glucose levels rather than real-time blood glucose levels;thus,there will be a delay in the treatment of hyperglycemia and hypoglycemia in patients.Recently,the European Union approved a state-of-art artificial intelligence directed loop system coordinated by CGM and a continuous insulin pump for diabetes control,which may provide a practical way to prevent acute adverse glycemic events related to antidiabetic therapy in critically ill patients.In this mini-review paper,we describe the application of CGM to patients in the ICU and summarize the pros and cons of CGM.

Beam Characteristics at Low Dose Monitor Unit Settings for Vero4DRT

The stability of delivery of low monitor unit (MU) setting is important especially for step-and-shoot intensity-modulated radiotherapy (IMRT), because the nature of the technique is inherent to repeat beam on/off according to the number of the segments. This study evaluates the dose linearity and profile flatness/symmetry under low MU settings for Vero4DRT, a new linear-accelerator based irradiation system that currently implements step-and-shoot IMRT. To evaluate the dose linearity and flatness/symmetry, the point doses and beam profiles were measured as functions of MU and dose rates. The accuracy of dose delivery depended on the dose rate. Under all dose rates, the dose was linear within 1% above 5 MU and within 2% above 3 MU. The beam symmetry was degraded in-line compared with crossline, although both profiles were symmetric within 2% at all dose settings. The profile flatness was also within 2% above 5 MU at any dose rate and showed no significant variation among the low MU settings. To ensure stable beam delivery without increasing the treatment time of Vero4DRT, we recommend a delivery of 5 MU per segment at a dose rate of 500 MU/min.

Adaptive Signal Enhancement Unit for EEG Analysis in Remote Patient Care Monitoring Systems

In this paper we propose an efcient process of physiological artifact elimination methodology from brain waves(BW),which are also commonly known as electroencephalogram(EEG)signal.In a clinical environment during the acquisition of BW several artifacts contaminates the actual BW component.This leads to inaccurate and ambiguous diagnosis.As the statistical nature of the EEG signal is more non-stationery,adaptive ltering is the more promising method for the process of artifact elimination.In clinical conditions,the conventional adaptive techniques require many numbers of computational operations and leads to data samples overlapping and instability of the algorithm used.This causes delay in diagnosis and decision making.To overcome this problem in our work we propose to set a threshold value to diminish the problem of round off error.The resultant adaptive algorithm based on this strategy is Non-linear Least mean square(NL2MS)algorithm.Again,to improve this algorithm in terms of ltering capability we perform data normalization,using this algorithm several hybrid versions are developed to improve ltering and reduce computational operations.Using the method,a new signal enhancement unit(SEU)is realized and performance of various hybrid versions of algorithms examined using real EEG signals recorded from the subject.The ability of the proposed schemes is measured in terms of convergence,enhancement and multiplications required.Among various SEUs,the MCN2L 2MS algorithm achieves 14.6734,12.8732,10.9257,15.7790 dB during the artifact removal of RA,EMG,CSA and EBA components with only two multiplications.Hence,this algorithm seems to be better candidate for artifact elimination.

Advancement in Wide Area Monitoring Protection and Control Using PMU’s Model in MATLAB/SIMULINK

A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station.

ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units

ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and fault retrieval; (4) Data aquisition, analysis and storage during daily operation; (5) Recall of historic data; (6) Output of routine reports and tables; (7) Analysis of vibration behaviour: Bode plot, polar plot, spectrum, cascade, waveform, shaft orbit, trend, etc;

What,why and how to monitor blood glucose in critically ill patients

Critically ill patients are prone to high glycemic variations irrespective of their diabetes status.This mandates frequent blood glucose(BG)monitoring and regulation of insulin therapy.Even though the most commonly employed capillary BG monitoring is convenient and rapid,it is inaccurate and prone to high bias,overestimating BG levels in critically ill patients.The targets for BG levels have also varied in the past few years ranging from tight glucose control to a more liberal approach.Each of these has its own fallacies,while tight control increases risk of hypoglycemia,liberal BG targets make the patients prone to hyperglycemia.Moreover,the recent evidence suggests that BG indices,such as glycemic variability and time in target range,may also affect patient outcomes.In this review,we highlight the nuances associated with BG monitoring,including the various indices required to be monitored,BG targets and recent advances in BG monitoring in critically ill patients.

Online Fault Detection Configuration on Equipment Side of a Variable-Air-Volume Air Handling Unit

With the development of the technology of the Internet of Things,more and more operational data can be collected from air conditioning systems.Unfortunately,the most of existing air conditioning controllers mainly provide controlling functions more than storing,processing or computing the measured data.This study develops an online fault detection configuration on the equipment side of air conditioning systems to realize these functions.Modbus communication is served to collect real-time operational data.The calculating programs are embedded to identify whether the measured signals exceed their limits or not,and to detect if sensor reading is frozen and other faults in relation to the operational performance are generated or not.The online fault detection configuration is tested on an actual variable-air-volume(VAV)air handling unit(AHU).The results show that the time ratio of fault detection exceeds 95.00%,which means that the configuration exhibits an acceptable fault detection effect.

Research and Development of a Communication Monitor to a Distribution Management System

Based on the existed equipment (the power line carrier, optic fiber, twisted pair and wireless apparatus) being used to the same route in the current communication net of distribution management system (DMS), this paper presents a new kind of communication monitor DMS, which provides a communication monitoring interface and then by DMS, data transfer problem from field terminal unit to junction center station can be solved and the communication channels can also be supervised. At the same time, synthetically using computer communication, internet technology and database technology, this system can realize the real time monitoring and fault locating in the communication network.

Research on Network-based Integrated Condition Monitoring Unit for Rotating Machinery

In this paper, a network-based mo nitoring unit for condition monitoring and fault diagnosis of rotating machinery is designed and implemented. With the technology of DSP(Digital signal processi ng), TCP/IP, and simultaneous acquisition, a mechanism of multi-process and int er-process communication, the integrating problem of signal acquisition, the da ta dynamic management and network-based configuration in the embedded condition monitoring system is solved. It offers the input function of monitoring informa tion for network-based condition monitoring and a fault diagnosis system.

基于WiFi6 MU-MIMO的非接触人体呼吸监测方法

WiFi6技术中引入多用户多输入输出(Multi-User Multiple Input Multiple Output,MU-MIMO)技术,作为支持多用户并发数据传输的重要手段。借用该技术中的多波束生成方法,可实现对人体呼吸的非接触式监测,从而避免传统佩戴式传感器引入的各种不便。利用双波束相干检测实现对人体呼吸频率的测量,借助WiFi6接入点(Access Point,AP)波束赋形功能将探测信号汇聚在两个波束;AP根据接收机测量到的两个波束功率差别,调整两个波束各子载波的功率大小,实现两个波束在接收机端的各子载波幅度相等;AP补偿两波束因路程差造成的固定相位差,使得人体呼吸引起的两波束周期性相位差转化为相干信号强度的周期性变化,实现了对人体呼吸微弱信号的提取,获得了人体呼吸频率,相对于传统方法可以得到更高的信号质量和更好的信噪比。

基于门控循环单元网络的钻井井漏智能监测方法

井漏是钻井过程中常见的钻井风险,若对该风险发现、处理不及时,极易导致井塌事故,轻则延长施工周期,重则危害现场人员人身安全。为了提高油气井钻井过程中井漏风险识别的准确性,降低风险识别对人为经验的依赖,结合钻井参数的非线性以及长时依赖特征,提出了一种基于门控循环单元(Gated Recurrent Unit,GRU)网络的井漏风险智能识别方法。该模型以池体积、出口流量和立管压力作为监测参数构建GRU网络,能够提取监测参数的时间序列特征,以实现对井漏风险的准确识别。利用现场实测钻井数据对模型进行了实验测试,结果表明,该方法对井漏风险的识别准确率达到了90.1%,优于长短期记忆网络的识别结果。

基于声纹监测技术的大型泵站机组振动特性研究

声音和振动是反映旋转机械设备运行状态信息的直接载体,根据声纹监测的原理,通过对数据进行采集、预处理、提取特征值,采用卷积神经网络深度学习识别模型,建立大型泵站机组运行状态声纹样本库和模型库,构建泵站机组振动状态的声纹监测系统,实现大型泵站机组运行状态的实时监测。

基于数字孪生的工业机器人建模及监测方法

针对工业机器人数据不透明、监测存在死角等问题,通过对实体工业机器人分析和研究,构建数字孪生机器人监测系统。首先从几何、物理、逻辑3个维度完成虚拟机器人的建模;其次基于开放平台通信联合架构(open platform communications united architecture,OPC UA),实现机器人的数据采集和通信,设计用户显示界面,达到数据实时可视化的效果;最后,通过机器人仿真实验得出机器人末端执行器X、Y、Z坐标的相对位置误差分别为0.48%、0.32%、0.27%,通过数字孪生机器人监测同步实验验证机器人关节角度误差最大值为0.31°。实验结果表明:该方法能够实现数字孪生工业机器人的运动数据监测,减少工业机器人在生产过程中发生意外和故障的风险,为智能工业机器人的发展提供思路和方向。

基于VMD-TCN的水电机组健康状态监测系统设计

针对常规的水电机组运行监测系统以高频振动信号监测为主,低频振动信号监测失误问题较多,影响水电机组正常运行的问题,设计了基于VMD-TCN的水电机组健康状态监测系统。硬件方面,设计了AC102加速度传感器;软件方面,采集水电机组健康状态数据,对水电机组状态信号进行处理,判断机组健康状态。基于VMD-TCN分解水电机组健康状态监测信号,根据采集到的状态信号进行信号频段子模态分解,确保监测精准度。系统测试结果表明:该设计提升了系统的监测效果,系统性能良好。

食管癌IMRT计划设计降低子野数及MU数方法研究

目的:研究降低食管癌调强计划子野数及MU数的可行性方法。方法:(1)射野方向:IMRT计划由物理师按照经验非均匀共面布野。(2)优化强度级数:分别设计为12、10、8、6优化强度级数。(3)围绕PTV连续定义六个和PTV同心的空心环并限制每个环剂量的计划(4)直接子野优化方法:使用DMPO模式设计,该模式允许预先设定最多子野数。结果:(1)选择的共面非均匀布野与均匀布野调强计划相比,肿瘤靶区的适形度、均匀性较好,总子野数和MU数无差异。(2)优化强度级数为12、10和8的计划质量基本相当,都满足食管癌临床要求,但优化强度级数为8的计划总子野数减少17%,MU数基本不变。(3)设定同心环并限制每个环剂量的计划,肿瘤受照剂量的适形度和正常组织受量均明显好于没有设定椭圆环的调强计划,同时该计划总子野数减少23%、总MU数减少9%。(4)与两步法调强计划相比,DMPO模式PTV的适形度更好,总子野数比原计划减少37%,总MU数减少16%。结论:通过优化强度级数选择、定义治疗靶区同心空心环、直接子野优化等方法,在不改变甚至提高原计划质量的前提下,可以减少食管癌IMRT计划总子野数和MU数。