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61.
As a novel parallel hip joint simulator, the 3SPS+1PS bionic parallel test platform with 4 degrees of freedom including three rotations and one translation is proposed. SPS denotes the spherical-prismatic-spherical leg and PS denotes the prismatic-spherical leg where only the prismatic joint is actuated and hence underlined. By means of the unit quaternion method, the formulae for solving the inverse/forward displacement, the inverse/forward velocity and the inverse/forward acceleration kinematics are derived. Using the unit quaternion to represent the position and orientation of a moving platform, singularities caused by Euler angles can be avoided. Combining the topological structure characteristics of the 3SPS+1PS bionic parallel test platform and letting the three-dimensional (3-D) motion of a human hip joint as its output movement, the displacement trajectories of three active legs are constructed based on the inverse displacement kinematics. The forward kinematic tests whose data are recorded by a 3-D orientation capture system are carried out on the developed parallel hip joint simulator. Moreover, the results of the forward kinematic tests prove that the 3SPS+1PS bionic parallel test platform can approximately represent human hip joint motion and provide more reliable experimental data for hip joint prostheses in clinical application.  相似文献   
62.
《Ergonomics》2012,55(6):1012-1021
For decades, research to quantify the effects of firefighting activities and personal protective equipment on physiology and biomechanics has been conducted in a variety of testing environments. It is unknown if these different environments provide similar information and comparable responses. A novel Firefighting Activities Station, which simulates four common fireground tasks, is presented for use with an environmental chamber in a controlled laboratory setting. Nineteen firefighters completed three different exercise protocols following common research practices. Simulated firefighting activities conducted in an environmental chamber or live-fire structures elicited similar physiological responses (max heart rate: 190.1 vs 188.0 bpm, core temperature response: 0.047°C/min vs 0.043°C/min) and accelerometry counts. However, the response to a treadmill protocol commonly used in laboratory settings resulted in significantly lower heart rate (178.4 vs 188.0 bpm), core temperature response (0.037°C/min vs 0.043°C/min) and physical activity counts compared with firefighting activities in the burn building.

Practitioner Summary: We introduce a new approach for simulating realistic firefighting activities in a controlled laboratory environment for ergonomics assessment of fire service equipment and personnel. Physiological responses to this proposed protocol more closely replicate those from live-fire activities than a traditional treadmill protocol and are simple to replicate and standardise.  相似文献   
63.
为满足实验室单克隆抗体的制备研究,本实验特对实验室常用的制备单抗的模拟抗原(Ac-NK16-Ahx-3)进行ELISA间接法检测,进而建立一种高效的检测方法。通过对不同稀释度待测抗体的免疫吸附测定,检测出它的最终灵敏度为0.078mg/mL,最佳二抗稀释倍数为300倍,其最佳拟合曲线为y=-0.0732x+0.6875,R2=0.8619。并且,通过统计学方法进行统计分析,确定出各实验组的相关性及变异系数,从而排除实验中的操作误差,最终可确定最佳的实验条件,并保证实验的准确性。  相似文献   
64.
65.
The work presented in this paper focuses on improving coal loading performance of shear drum.Employing the similarity theory,we carried out a dimensional analysis of the correlation parameters which in...  相似文献   
66.
论述高校党建工作网络信息化的重要意义,指出构建党建工作信息化平台要体现三个特征,从信息化观念、信息素养水平、高校特色、师生党员归属感等方面,对网络平台的搭建和党建信息化的开展进行了探讨,并提出了相应的对策。  相似文献   
67.
水泵选型应用研究的目的是用计算机来代替传统的纸质资料。系统地介绍了在水泵选型应用系统中利用网络进行CAD在线绘图的特点、CAD在线绘图的设计构思以及实现方法,为B/S结构的水泵选型应用系统奠定基础。  相似文献   
68.
以广东省1993--2011年相关时间序列数据为基础,建立了反映电网建设水平与社会经济发展关系的向量自回归(VAR)模型,在VAR模型的基础上,分析了广东省电网建设指标与社会经济发展指标的格兰杰因果关系,运用脉冲响应函数和方差分解方法分析了电网建设与社会经济发展之间的动态影响。研究结果表明,电网建设是经济增长的基础条件之一,在电网建设与经济增长的相互作用中,电网建设对经济增长的促进作用更为显著。  相似文献   
69.
This paper presents the results of a Round-Robin Test on methods for determining chloride transport parameters in concrete, carried out by the Technical Committee TC 178-TMC: “Testing and Modelling Chloride Penetration in Concrete” in which 27 different laboratories around the world have participated, using 13 different methods, in triplicate specimens, for 4 different mixes of concrete cast with different binders. Four different groups of methods have been tested: Natural diffusion methods (D), Migration methods (M), Resistivity methods (R) and Colourimetric methods (C). The statistical treatment of the data has been carried out according to the International Standard ISO 5725-2:1994 for the determination of the accuracy (trueness and precision) of measurement methods and results. Part 2: Basic method for the determination of the repeatability and reproducibility of a standard measurement method. In order to make an evaluation of these methods, four indicators have been identified and within each of them, several sub-indicators have been assigned. According to this system of classification, the methods have been classified following each indicator (trueness, precision, relevance and convenience), and also globally, by assigning different factors of importance, F.I., to the different indicators.  相似文献   
70.
Experimental tests are described to check solid 241Am radioactive sources used to monitor operation of liquid xenon detectors. In particular, radioactive leakage was tested in extreme temperature conditions following immersion in liquid nitrogen for different time periods. No radioactivity loss was detected from the sources considered. The paper describes the source characteristics, test methods and results obtained.  相似文献   
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