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作者：刘开征南开大学

学位级别：硕士

自动桥式吊车系统是工业自动化的一个重要研究领域，相比人工操作系统，提高了运送效率、定位精度和安全系数。为了进一步提高自动桥式吊车系统的安全性能，本文设计开发了一款易与嵌入式硬件系统融合，使用简单方便，可在自动操作和手... 详细信息

自动桥式吊车系统是工业自动化的一个重要研究领域，相比人工操作系统，提高了运送效率、定位精度和安全系数。为了进一步提高自动桥式吊车系统的安全性能，本文设计开发了一款易与嵌入式硬件系统融合，使用简单方便，可在自动操作和手动操作之间实现平滑切换的智能操纵杆。本文工作主要包括以下方面：\n (1)对真实吊车操纵装置以及自动化系统中手动操控方案进行调研，选择使用工业操纵杆作为吊车的输入设备，并确定了将其应用在自动桥式吊车嵌入式系统上以完成手动操纵的设计方案。\n (2)以DSP(Digital Signal Processor，数字信号处理器)+FPGA(FieldProgramming Gate Array，现场可编程门阵列)嵌入式实时硬件系统平台为基础，设计实现了操纵杆接入电路和相关接口，主要包括模拟放大电路、电压跟随隔离电路和模拟数字转换电路。\n (3)结合硬件系统的特点，设计了操纵杆应用软件，详细介绍了操纵杆应用的软件结构和主要流程。软件设计部分包括模拟输入信号转换为数字信号，吊车动作编码和数字控制指令转换成吊车控制模拟信号，为操纵杆操作吊车实现各项功能奠定了基础。\n (4)在自动桥式吊车嵌入式硬件系统平台上，对操纵杆软硬件设计进行了安装、调试和运行，并通过相关实验验证了操纵杆实时操作吊车的可行性，以及手动操作在自动吊车系统上的良好适应性，同时具备较高的安全性、实时性和可靠性。最后，通过一系列实验展示了操作人员利用操纵杆完成吊车二维空间运动，三维空间负载运送以及手动操作模式和自动操作模式之间平滑无扰动切换功能。

关键词：操纵杆自动桥式吊车系统模拟数字转换数字信号处理器现场可编程门阵列嵌入式硬件系统

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Fluid dynamics of a pediatric ventricular assist device (vol 24, pg 362, 2000)

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ARTIFICIAL ORGANS 2000年第12期24卷 989-989页

作者： Bachmann, C BioengineeringDepartment thePennsylvaniaStateUniversityUniversityParkPA16802USA.

The number of pediatric patients requiring some form of mechanical circulatory assistance is growing throughout the world because of new surgical procedures and the success of pediatric cardiac transplantation. However, the salvage rate for those patients requiring circulatory support may be as low as 25%. Despite the fact that Penn State's 70 cc pneumatic ventricular assist device has been used with a success rate of over 90% in more than 250 patients worldwide, efforts to scale down the pump have encountered difficulties. Animal experiments with a 15 cc version were unsuccessful, with explanted pumps showing extensive thrombus deposition within the pumping chamber. The materials used to fabricate the smaller pump as well as the basic operating principles are identical to the successful adult-sized version. It is therefore believed that reducing the size of the pump altered the internal flow field, and that fluid dynamic factors were responsible for the high degree of thrombus observed with the implanted devices. A dimensional analysis was conducted that revealed significant differences in both Reynolds (Re) and Strouhal (St) numbers between the successful and unsuccessful pumps. Two component laser Doppler velocimetry was then used to characterize the internal flow field quantitatively. Comparison with data from the 70 cc pump showed a reduction in wall shear stress and turbulence levels in the 15 cc pump that would yield an environment conducive to clot formation.

关键词：模拟数字转换生物相容性材料设备设计心脏移植心脏辅助装置血液流变学激光多普勒流量测定流变学信号处理计算机辅助应力物理表面特性外科手术血栓形成/病因学成年人动物儿童人类

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Video transmission for telemedicine

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JOURNAL OF TELEMEDICINE AND TELECARE 1999年第1期5卷 1-10页

作者： Squibb, NJ K Net Ltd Odiham England

The transmission of moving pictures to remote locations is an important part of telemedicine. Although the first videoconferencing demonstrations were performed in the 1930s, the technology is still fragmented and its quality is sometimes too poor for it to be useful. Conventional television technology is analogue (the fundamental television standards were developed before the Second World War) and does not 'fit' the digital world very well. This paper reviews video transmission and videoconferencing technologies and the results that can be expected. While trained professionals may be able to make use of poor-quality video systems, real advances in telemedicine require studio-quality video, which is possible only with high-bandwidth technology.

关键词：模拟数字转换微型计算机信号处理计算机辅助远程医学/仪器和设备电视人类

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UTERINE CONTRACTILITY DATA-PROCESSING SYSTEM

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AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY 1975年第3期123卷 246-250页

作者： KEPKA, A BIENIARZ, J MUTSCHLER, L SHAH, N SCOMMEGNA, A UNIV CHICAGO PRITZKER SCH MEDCHICAGOIL MICHAEL REESE HOSP & MED CTR DEPT OBSTET & GYNECOLLAB UTERINE PHYSIOLCHICAGOIL MICHAEL REESE HOSP & MED CTR DEPT MED PHYSCHICAGOIL

A versatile system has been developed for off-line computerized quantitation of uterine contractility. It includes tabulation and display of intensity, frequency, resting tone, uterine activity, cumulative area below the pressure curve, and average intrauterine pressure. Its advantages and drawbacks are compared with the conventional method and with an automated on-line labor surveillance system.

关键词：模拟数字转换计算机分娩产道联机系统子宫收缩女(雌)性人类妊娠

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影像传感器、使用于其的模拟数字讯号处理方法和装置

影像传感器、使用于其的模拟数字讯号处理方法和装置

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作者：许晨声邱瑞德中国台湾新竹科学工业园区

使用于影像传感器的模拟数字讯号处理方法，包括：提供一全局式模拟数字转换器，该全局式模拟数字转换器可用以将该影像传感器之一像素数组之所有像素之复数个模拟讯号转换为复数个数字讯号；提供一并列式模拟数字转换器，该并列式模拟... 详细信息

标准号: CN107948553B

使用于影像传感器的模拟数字讯号处理方法，包括：提供一全局式模拟数字转换器，该全局式模拟数字转换器可用以将该影像传感器之一像素数组之所有像素之复数个模拟讯号转换为复数个数字讯号；提供一并列式模拟数字转换器，该并列式模拟数字转换器可用以通过复数个模拟数字转换电路分别将该像素数组于不同列上之复数个像素之复数个模拟讯号转换为复数个数字讯号；以及动态切换选择该全局式模拟数字转换器及该并列式模拟数字转换器的其中之一，对该像素数组之复数像素之数据执行一模拟数字转换。

关键词：模拟数字转换器复数像素数组并列式影像传感器模拟讯号数字讯号可用像素全局模拟数字转换电路模拟数字转换动态切换复数像素模拟数字数据执行讯号处理转换

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NONPAROXYSMAL JUNCTIONAL TACHYCARDIA IN ACUTE MYOCARDIAL-INFARCTION - COMPUTER-ASSISTED DETECTION

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AMERICAN JOURNAL OF CARDIOLOGY 1975年第6期35卷 824-830页

作者： KNOEBEL, SB RASMUSSEN, S LOVELACE, E ANDERSON, GJ INDIANA UNIV SCH MEDKRANNERT INST CARDIOLINDIANAPOLISIN INDIANA UNIV SCH MEDDEPT MEDINDIANAPOLISIN INDIANA UNIV SCH MEDDEPT COMP SERVINDIANAPOLISIN VET ADM HOSP INDIANAPOLISIN HENDRICKS CTY HOSP DANVILLEIN

Thirty consecutive patients with acute myocardial infarction had continuous magnetic tape recording of their electrocardiograms (lead II) for the period of their stay in the coronary care unit. Analysis of the 24 hour tape recordings was implemented on a Honeywell model 316 digital computer. In the first 24 hours after admission to the coronary care unit, 12 of the 30 patients (40 percent) exhibited nonparoxysmal junctional tachycardia; in 5 the arrhythmia was not recognized by conventional monitoring techniques. For the subsequent 3 days, the incidence rate of the arrhythmia was 13 percent for the first 48 hours and 3 percent for 72 hours. Although the mortality rate in patients with nonparoxysmal junctional tachycardia was greater than in patients not demonstrating the arrhythmia (33 versus 6 percent), there was a greater percentage of patients with anterior infarction in the former group; therefore, mortality may have been related to site of infarction rather than being reflective of the arrhythmia or its associated pathophysiologic state. Of possible significance is the association of a greater degree of sinus arrhythmia with nonparoxysmal junctional tachycardia. The incidence of nonparoxysmal junctional tachycardia in this group of patients was greater than previously reported. It is possible that computer tape analysis may have provided more accurate recognition of the arrhythmia and, thus, more realistic incidence data. The association of nonparoxysmal junctional tachycardia with sinus arrhythmia could only have been recognized by computer technique. The computer system is not a diagnostic system but rather a tape review method.

关键词：模拟数字转换心律失常窦性/病因学冠心病重症监护病房诊断计算机辅助/仪器和设备诊断计算机辅助/方法心电描记术/仪器和设备心电描记术/方法心肌梗死/并发症心肌梗死/死亡率预后心动过速/病因学心动过速/死亡率人类

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Spectral analysis of heart rate and blood pressure variability in primary Sjogren's syndrome

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ANNALS OF THE RHEUMATIC DISEASES 2002年第3期61卷 232-236页

作者： Barendregt, PJ Tulen, JHM van den Meiracker, AH Markusse, HM Med Centrum Rijnmond Zuid Dept Rheumatol Rotterdam Netherlands Univ Hosp Dijkzigt Dept Psychiat NL-3015 GD Rotterdam Netherlands Univ Hosp Dijkzigt Dept Internal Med NL-3015 GD Rotterdam Netherlands

Background: Autonomic dysfunction has been described in primary Sjogren's syndrome (SS). Objective: To investigate the circulatory autonomic regulation in patients with primary SS by power spectral analysis of heart rate and blood pressure variability. Methods: Forty three (42 female) patients with primary SS, mean age 52 years (range 23-80), with a mean disease duration of eight years (range 1-30) and 30 (15 female) healthy controls, mean age 43 years (range 21-68) were studied. In each patient blood pressure, heart rate, and respiration were measured continuously during supine rest and orthostatic challenge (60 head-up tilt). Power spectral analysis was performed to determine possible differences in short term sympathetic and parasympathetic autonomic regulation between patients and controls. Furthermore, spectral parameters were studied in relation to illness severity and disease duration of the patients with primary SS. Results: After controlling for differences in age, heart rate variability of the mid-frequency band and the variation coefficient of systolic blood pressure were significantly lower in patients with primary SS than in controls during supine rest. During 60 tilt patients with primary SS showed a significantly higher mean heart rate, mean systolic blood pressure, and variation coefficient of diastolic blood pressure, and a significantly lower baroreflex index than controls. After controlling for age, no differences were found either in heart rate variability, blood pressure results, and baroreflex sensitivity during supine rest and tilt between the subgroups divided according to disease duration, Schirmer test results, or between the subgroups with different fatigue scores. No differences were found in spectral data between the groups with and without positive antinuclear antibody serology. Conclusion: For the group no differences in sympathetic and parasympathetic cardiac control were seen between patients with primary SS and controls, as assessed

关键词：模拟数字转换自主神经系统/生理学压力感受器反射/生理学血压/生理学病例对照研究傅里叶分析心率/生理学呼吸疾病严重程度指数干燥综合征/病理生理学仰卧位成年人老年人老年人 80以上女(雌)性人类男(雄)性中年人

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Digital imaging in the assessment of facial deformity

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BRITISH JOURNAL OF ORAL & MAXILLOFACIAL SURGERY 1999年第2期37卷 94-98页

作者： Fanibunda, KB Thomas, PR Newcastle Univ Sch Dent Dept Oral & Maxillofacial Surg Newcastle Upon Tyne NE2 4BW Tyne & Wear England Newcastle Univ Dept Geomat Newcastle Upon Tyne NE2 4BW Tyne & Wear England

A combination of digital imaging and conventional radiographic techniques has been used to obtain a life-size composite image of the facial soft tissue profile, the skull, and the teeth, anatomically superimposed on each other. The system overcomes major problems associated with assessment of facial deformity such as magnification, the exposure of photographs and radiographs from different positions, radiographs with overexposed soft tissue profiles, lengthy procedures in photographic studios, and, in addition, enables a degree of partial automation in the management of patients.

关键词：模拟数字转换测颅法/仪器和设备测颅法/方法面部/解剖学和组织学图像处理计算机辅助/方法颌面畸形/放射摄影术摄影术/仪器和设备 X线影像增强放射摄影术牙科/方法放射摄影术牙科数字人类

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Adaptive Digital Calibration of Amplifier Finite Gain Effects and C-ratio Matching Errors for MASH Modulators

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High Technology Letters 2004年第4期10卷 15-18页

作者：冯晖 Lin Zhenghui Electronic Engineering Department Shanghai Jiaotong University Shanghai 200030 P.R.China

Cascaded sigma-delta (MASH) modulators for higher order oversampled analog-to-digital conversion rely on precise matching of contributions from different quantizers to cancel lower order quantization noise from intermediate delta-sigma stages. This paper studies the effect of analog imperfections in the implementation, such as finite gain of the amplifiers and capacitor ratio mismatch, and presents an adaptive algorithm and implementation architectures for digital correction of such analog imperfections. Behavioral simulations on 1-1-1 oversampled converters demonstrate over 10dB improvements in signal-to-noise and over 20 dB improvements in dynamic range performance.

关键词：求和增量调节器 MASH 数字校准技术噪音 A/D转换模拟数字转换

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影像传感器、使用于其的模拟数字讯号处理方法和装置

影像传感器、使用于其的模拟数字讯号处理方法和装置

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作者：许晨声邱瑞德中国台湾新竹科学工业园区

标准号: CN107948553A

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