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991.
OBJECTIVE: To describe a new method for measuring lateral neck flexion range of motion (ROM), document the reliability of the method and present estimates of normal. SUBJECTS: One hundred thirty-five subjects ranging in age from 14-95 yr. Two physical therapists with 13 and 2 yr of experience, respectively, served as testers. INTERVENTION: Measurement of active lateral neck flexion ROM using a universal goniometer modified by the placement of a portion of a small paper clip through the axis. The goniometer arms were aligned with the subject's nose, and the free-swinging paper clip (pendulum) was used as a marker. The more experienced therapist measured lateral flexion of 100 subjects to establish intratester reliability and estimates of normal. Both therapists measured 35 subjects to determine intertester reliability. MAIN OUTCOME MEASURE: Degrees of lateral neck flexion. RESULTS: Intraclass correlation coefficients for intratester reliability exceeded 0.90. Coefficients for intertester reliability were 0.86 and 0.65. ROM decreased with increasing age. CONCLUSION: The modified goniometer is inexpensive, easy to use and can yield high intratester reliability and satisfactory intertester reliability. The estimates of normal provide preliminary values with which a patient's lateral neck flexion ROM can be compared. 相似文献
992.
Ken Nishina 《Quality and Reliability Engineering International》1992,8(6):537-541
ISO/DIS 7870 has presented the cumulative sum chart, the moving average chart, and the exponentially weighted moving average chart as control charts using accumulated data. In this paper, we compare the three control charts in terms of change-point estimation. We show the probability distribution, the bias and the mean square error of the change-point estimators using a Markov process and Monte Carlo simulation. These control charts have almost equivalent performances based on average run length considerations when parameters of each control chart are set appropriately. However, from the viewpoint of change-point estimation we recommend the CUSUM chart. 相似文献
993.
A Kashimada K Machida N Honda T Mamiya T Takahashi T Kamano M Muramatsu Y Inoue 《Canadian Metallurgical Quarterly》1992,29(9):1127-1131
99mTc-ECD SPECT and 99mTc-HMPAO SPECT with or without Matas test were performed in a 62-year-old woman with meningioma in the left anterior cranial fossa. After injection of 740 MBq 99mTc-ECD or HMPAO, 64 projection images were collected with a rotating Gamma camera. Matas test was carried out by compressing the left common carotid artery for about one minute immediately after RI injection. Although 99mTc-ECD SPECT showed non-accumulation in the tumor, 99mTc-HMPAO SPECT demonstrated increased accumulation in it. This area of increased accumulation disappeared on 99mTc-HMPAO SPECT with Matas test which causes decrease in blood flow of the tumor. These findings suggest 99mTc-ECD and 99mTc-HMPAO have a different mechanisms of accumulation in the meningioma. 相似文献
994.
The overlap-add method (OLA) and overlap-save method (OLS) are well known as efficient schemes for high-order FIR filtering. In this correspondence, new sampling rate conversion methods are proposed by extending the OLA and OLS and eliminating the redundancy caused by the conversion. First, for finite-duration sequences, a rate conversion with the DFT-domain approach is discussed. Then, using the result, the extended OLA and OLS are proposed for infinite-duration sequences. Last, the computational complexities of our proposed methods are shown 相似文献
995.
Francisco Maturana Raymond Staron Ken Hall Pavel Tichý Pavel Vrba Vladimír Maík 《Robotics and Computer》2008,24(5):616
We are interested in providing an agent infrastructure for truly distributed control. Requirements include multiple language implementations, so that this agent host environment can exist in both real-time controllers and contain the ability to operate with external agent systems. Our first infrastructure, the Autonomous Cooperative System (ACS), accomplished these goals, but presented other issues. Although ACS has been successfully deployed on commercial controllers, new releases of controllers will cause complications in the evolution of the software and adoption of future functionality. We need to establish a formal integration procedure of the agent functionality with the controllers and to transform the underlying system into a fully integrated and open heterogeneous system. We use a shipboard automation example to demonstrate the use of the agent virtual machine. With this system, the shipboard automation system is designed as a distributed and survivable environment, thereby spreading intelligence throughout the controllers and not in central locations. 相似文献
996.
KenO’Neill 《电子与电脑》2005,(11):27-29
在设计高可靠性系统时,无论是陆地、航空或太空应用,设计人员都必须非常小心地选择器件技术。如果选择不当会导致FIT(FailuresInTime)大幅度提高,即使基站应用也不例外。军事和航空设计人员认识到半导体器件存在单事件翻转(SingleEventUpset;SEU)效应,以及基于SRAM技术器件的相关软错误率(SoftErrorRate;SER)。SEU的发生是由于带电的亚原子粒子撞击触发器或SRAM单元,这个进入的粒子会沉积足够的电荷,导致触发器或存储器单元的状态改变,以致损坏所存储的数据。因为这种现象不会永久损坏存储单元,SEU常被称为软错误。在太空应用… 相似文献
997.
Ken Sawai Yuichi Tsuboi Masashi Shiota Nobumitsu Hirai Shigeharu Osumi 《Journal of power sources》2008
Potential step was applied to Pb–Ca–Sn alloy electrode at various potential and time regimes. No severe corrosion was observed during potential step cycle with cathodic potential under −140 mV or over −40 mV versus Pb/PbSO4 (3.39 M H2SO4), or at constant potential without stepping. On the other hand, the Pb–Ca–Sn alloy was severely corroded during potential step with cathodic potential from −120 mV to −60 mV and with anodic potential of +40 mV or more positive. The corrosion could not be decreased with periodical rest at 0 mV, while it could be decreased with periodical reduction at high polarization of, e.g. −160 mV. It was found out that the severe corrosion occurs when the oxidation of Pb to PbSO4 and partial reduction of passive film of PbSO4 take turns many times. 相似文献
998.
Francisco Maturana Raymond Staron Ken Hall Pavel Tichý Pavel Vrba Vladimír Mařík 《Robotics and Computer》2008
We are interested in providing an agent infrastructure for truly distributed control. Requirements include multiple language implementations, so that this agent host environment can exist in both real-time controllers and contain the ability to operate with external agent systems. Our first infrastructure, the Autonomous Cooperative System (ACS), accomplished these goals, but presented other issues. Although ACS has been successfully deployed on commercial controllers, new releases of controllers will cause complications in the evolution of the software and adoption of future functionality. We need to establish a formal integration procedure of the agent functionality with the controllers and to transform the underlying system into a fully integrated and open heterogeneous system. We use a shipboard automation example to demonstrate the use of the agent virtual machine. With this system, the shipboard automation system is designed as a distributed and survivable environment, thereby spreading intelligence throughout the controllers and not in central locations. 相似文献
999.
Chandra Nath Mustafizur Rahman Ken Soon Neo 《International Journal of Machine Tools and Manufacture》2009,49(14):1089-1095
Sintered tungsten carbide (WC) is an extremely hard and brittle material extensively used in tool manufacturing industries. However, the current cutting technologies for shaping this typical hard-to-machine material are still cost ineffective. In this study, polycrystalline diamond (PCD) tools are used to study the machinability of sintered WC (~15% Co) by applying the ultrasonic elliptical vibration cutting (UEVC) technique. Firstly, it presents the UEVC principle and the effects of speed ratio (i.e. the ratio of the nominal cutting speed to the maximum tool vibration speed in the cutting direction) on the tool–workpiece relative motion as the cutting speed greatly influences the UEVC performance. Then UEVC experiments are carried out to analyze the cutting force, tool-wear progression, chip formation and surface quality against the cutting time at different speed ratios. The results show that when the speed ratio decreases, the resultant cutting force and the tool flank wear decrease while the surface finish improves. Average surface roughness, Ra, in a range between 0.030 and 0.050 μm is achieved at speed ratios less than 0.107. The experimental findings suggest that the commercial PCD tools can be used to machine sintered WC to achieve ultraprecision surface by applying the UEVC technique, which will be cost effective for miniature cutting technologies in future. 相似文献
1000.