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1.
Cyclic voltammetric and galvanostatic experiments have been carried out with both synthetic and commercial bleach solutions with a view to regenerating the same. Maximum efficiency could be achieved if the oxidation is carried out below an anodic potential of 0·80 V vs SCE. The data obtained in galvanostatic experiments with RCE confirm the results of the earlier technique.  相似文献   
2.
快速发展中的工科背景高等院校在统计教育上存在有待改进的地方。以浙江科技学院为例,为培养具有深厚统计学背景的应用型复合人才,在统计教育上作了一些探索:定位于浙江中小企业对统计知识的实际需求;选择注重实际应用的国外经典教材;在教学中注重学生的参与;在实践中培养学生运用统计学知识和统计工具如统计软件的能力。  相似文献   
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A stochastic differential equation involving both a Wiener process and fractional Brownian motion, with nonhomogeneous coefficients and random initial condition, is considered. The coefficients and initial condition depend on a parameter. The assumptions on the coefficients and the initial condition supplying continuous dependence of the solution on a parameter, with respect to the Besov space norm, are established.  相似文献   
5.
This paper presents a general method to formulate monotonically convergent algorithms for identifying optimal control fields to manipulate quantum dynamics phenomena beyond the linear dipole interaction. The method, facilitated by a field-dependent dipole moment operator, is based on an integral equation of the first kind arising from the Heisenberg equation of motion for tracking a time-dependent, dynamical invariant observable associated with a reference control field.  相似文献   
6.
Abstract. The limiting process of partial sums of residuals in stationary and invertible autoregressive moving-average models is studied. It is shown that the partial sums converge to a standard Brownian motion under the assumptions that estimators of unknown parameters are root- n consistent and that innovations are independent and identically distributed random variables with zero mean and finite variance or, more generally, are martingale differences with moment restrictions specified in Theorem 1. Applications for goodness-of-fit and change-point problems are considered. The use of residuals for constructing nonparametric density estimation is discussed.  相似文献   
7.
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   
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《Ergonomics》2012,55(3):269-281
The maximum voluntary range of motion (ROM) of the major joints of the upper body was studied in a seated position and compared between young and elderly subjects. A total of 41 subjects (22 young male and female subjects aged 25 to 35 years, 19 elderly male and female subjects aged 65 to 80 years) took part in the experiment. In total, 13 maximum voluntary joint motions were performed by each subject. Age was found to have a non-uniform effect on the ROM of the joints investigated in this study. Its effect on ROM was joint specific and motion specific. The highest loss in ROM was observed in the neck and trunk, especially for neck extension, lateral flexion and axial rotation as well as for trunk lateral flexion and axial rotation. No significant age differences were observed in the elbow and wrist joint ROMs. The effect of gender on joint ROM was much weaker than that of age. Only four among the 26 joint ROMs investigated in this study were significantly different between the two gender groups.  相似文献   
10.
螺纹梳刀是加工螺纹一种刀具,被广泛应用于加工石油、建筑行业用的螺纹中。螺纹梳刀切头加工螺纹的最大优势在于效率高,将加工时间缩短一半以上,并且能保证工件的受力平衡,特别是应用在活动钳口螺纹的加工上。本文探索螺纹梳刀的结构特点,分析了螺纹梳刀的发展,同时在Pro/E中进行模拟加工及运动分析。  相似文献   
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