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1.
2007年,在我国经济快速发展,人民健康意识显著提高、医疗保险政策逐步向好等利好的推动下,中国医疗电子市场持续增长,其规模达到247.3亿元,同比增长17.3%.细分市场中,电子仪器及设备、射频仪器、超声仪器、激光仪器及设备、生化分析仪这五大产品也呈现不同的发展态势.其中,医用电子产品份额仍然稳居首位、医用射频设备增速回升、医用超声波设备前景乐观.  相似文献   

2.
设计研制一种与医学介入导管技术结合的超声辐照治疗仪。并介绍治疗仪的结构设计、工作原理和性能测试。该医用介入超声治疗仪由超声辐照导管和主机构成。超声辐照导管顶端安装有微型压电换能器,可进入人体深部脏器内近距离直接辐照组织,并较准确控制辐照在组织的超声能量和效应;激发微型换能器发射超声的主机设计为频率、功率大小可调节,满足不同的治疗需要,具有广阔的应用前景。  相似文献   

3.
胎儿心率检测是胎儿监护的蕾要环节,它对于实现优生优育具有重要的意义。首先介绍了医用超声多普勒胎儿心率检测系统的整体结构,然后对伪随机码的距离选通原理作了介绍,并用仿真软件systemView对系统及其性能进行了仿真.从而说明系统采用伪随机码比使用连续波更具有优点。  相似文献   

4.
医疗应用中的多普勒超声波检查包含连续波(CW)多普勒和脉冲(PW)多普勒两种技术,其中PW多普勒主要用于检测深度(距离)信息;CW多普勒则用于测量血流的速度和方向,可帮助医生更精确地诊断血管症状。针对CW和PW多普勒超声应用,ADI公司最新推出其八通道超声接收器系列的第三代产品——AD9276和AD9277,在单芯片中集成了CW多普勒信号处理的增益、滤波、  相似文献   

5.
阮航  吴彦鸿  叶伟 《激光与红外》2013,43(4):385-390
逆合成孔径激光雷达(inverse synthetic aperture ladar,ISAL)发射信号具有超短波长、超大带宽的特点,其回波对目标运动具有极强的敏感性,因而ISAL回波信号特征与常规ISAR回波有很大不同.建立了ISAL回波的精确模型,研究了由于目标运动引起的回波包络展缩、脉内多普勒和脉冲间多普勒效应,并给出了它们的近似方法及约束条件,仿真分析了目标在不同运动参数下回波信号的包络展缩、脉内多普勒效应对ISAL成像的影响,结果表明上述效应会造成图像的散焦,需要在成像中进行相应补偿.  相似文献   

6.
Rob Reeder 《电子设计技术》2008,15(7):133-134,145
上世纪90年代初,便携式电话风靡一时,随着电子技术的长足发展,现今的手机除了可以发送电子邮件和短信,还能拍照、查询股票价格、安排会议;当然,也可以同世界上任何地方的任何人通话。同样在医疗领域中,以前所谓的便携式超声系统曾装载在手推车上以便于拖拽;而今天的医用超声系统也在持续向小型化发展,  相似文献   

7.
基于三次样条重建的超声多普勒血流信号提取   总被引:1,自引:0,他引:1       下载免费PDF全文
陶倩  汪源源  王威琪 《电子学报》2005,33(1):154-157
根据超声多普勒血流信号和血管壁搏动信号的不同统计特性,对采集的多普勒信号进行非均匀抽样和三次样条函数重建,从中得到血管壁搏动信号,从而提取出超声多普勒系统中的血流信号.对计算机仿真的超声多普勒信号和采集的人体颈总动脉多普勒信号分别应用该方法,并和传统的高通滤波器方法进行比较.实验结果表明:本方法能在滤除管壁搏动信号的同时,保留低频部分的超声多普勒血流信号,可用于超声多普勒系统中两种信号成份的分离.  相似文献   

8.
利用电磁辐射信号进行雷电源探测和定位是当前雷电研究的重要探测手段,其定位结果的准确性对正确认识闪电的放电机理非常重要。本文通过数学推导建立了多普勒效应在球坐标下的定位影响理论模型;用Matlab软件进行模拟,分析了多普勒效应对阵列接收信号的影响及误差,研究了多普勒效应对运动雷电源定位结果产生的影响。研究结果表明,多普勒效应对于不同类型、不同距离、不同高度的闪电影响程度不同;根据雷电发展的不同阶段,雷电源的运动速度不同,多普勒效应带来的误差也不同,且其带来的误差是不可忽略的。该研究对实现更高时空分辨力的运动雷电源定位结果和雷电的精细化研究具有重要意义。  相似文献   

9.
本文借鉴船用多普勒计程仪技术,提出基于FPGA的频谱分析提取速度信息的具体实现进行了研究,完成一种完整的基于FPGA超声多普勒计程仪的系统设计和实现方法,该方法计算精度较高,系统实现简单灵活,为实现高效、准确的陆用超声多普勒计程仪提供了基础。  相似文献   

10.
针对目前超声多普勒胎心检测仪灵敏度不理想的问题,研究多普勒检测前置电路这一影响灵敏度的核心环节.首先基于超声多普勒信号检测的理论模型,通过比较不同前置电路的特点,提出并实现了新型前置电路方案,包括发射驱动电路和接收解调电路等;然后将新方案成功应用于多普勒胎心检测仪中.使用FS-3型超声多普勒胎儿心率测量仪检测装置进行检...  相似文献   

11.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

12.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

13.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

14.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

15.
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.  相似文献   

16.
It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).  相似文献   

17.
正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must  相似文献   

18.
正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-  相似文献   

19.
正Cloud computing is a novel computing paradigm that utilizes remote cloud resources to achieve a high-performance computation.Cloud provides infrastructure,platform and software as different on-demand services.China has made remarkable progress in cloudbased products and operating system technology.The government,enterprises and research institutions are all active in the development of cloud computing-related projects.Despite the progress,many important problems  相似文献   

20.
正Smart Grid Communications The electric power industry is undergoing profound changes as the industry aims to capture the promise of a smart grid for a sustainable energy future.Enabled by the advanced sensing devices such as Phasor Measurement Units(PMUs),increasingly powerful  相似文献   

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