1996, 11(2):65-70. DOI: 10.3871/j.1004-7220.1996.2.70.
Abstract:A whole human lumbar spine was used as experimental specimen,the parallel light 3-D movement measurement system was designed and applied, then 3-D movement parameter of Special point of lumbar spine posterior elements was obtained during varying movement.By means of an analysis of loading-displacement curve,we found regularity in the stereoscopic movement of important region of lumber spine posterior elements. During right rotation the relative motion of right L_4 inferior process of facet joint were 0.6mm (backward)1.0mm(upward) and 3.0mm (right lateralward), it resulted in enlarging the volume of L_5 nerve root canal.While flexional,no matter which lumber spinal section it is,the motion is foreward and upward with a little lateral displacement.The main movement axis of different segment of aged lumbar spine specimen changed not regularly in X and Z axes,the displacement variable were more large than that of young and middle age specimen in loading,due to degeneration and stability of specimen.
1996, 11(2):71-77. DOI: 10.3871/j.1004-7220.1996.2.77.
Abstract:In this paper the biomechanics analysis showed theoretically that the stress of cervical vertebrae using Traction and Counter-Traction Manipulation of Chinese massage is consistent with clinical mechanical requiremant.TCD indexes of VBI cervical spondylopathy cases before and after operation of Traction and Counter-Traction Manipulation changed obviously,it verified the Traction and Counter-Traction Manipulation had desirable curative effect on VBI.
1996, 11(2):78-82. DOI: 10.3871/j.1004-7220.1996.2.82.
Abstract:The purpose of this work is to investigate the effects of intensive exercise on the geometric morphology of sectional area and the mechanical properties of long bone. Thirty-four matured rabbits were put in an electric cage with hige pulsed voltage, which made the animals to do jump and run exercise 360 times daily for 6 weeks.The results of three point bending and torsion tests for whole tibia bone showed the mechanical properties strengthened significantly for the exercised animals.The results taken from the sectional area of tibia revealed that the inner and outer radii axes,major and minor moments of inertia,sectional modulus of bend were increased statistically. Asthe results of rationalization of the sectional area,the long bone can bear more severe stress during physical activities.It is a best way for the long bone to adapt the strenuous exercise.
1996, 11(2):83-86. DOI: 10.3871/j.1004-7220.1996.2.86.
Abstract:Tests in tension at strain rates from 4.0 ×10￣-5/s to 9.0×10￣-3/s are performed on wet human compact bone specimens by the Instron Testing Instrument. The unknown parameters in the damage model based on the parallel viscoelastic bar system are determined by experimental data and the higher correlation coefficient (R≥0.90) is obtained. The fracture surfaces of the specimens are observed and analyzed by scanning electron microscope. The results indicate that, under the quasi-static loading condition, microfractures propagate through cement lines and Haversian osteons are pulled out of bone matrix, just as a creep move. This shows that the damage mode of the sequential pull-out of the osteons from bone matrix is reasonable.
1996, 11(2):87-91. DOI: 10.3871/j.1004-7220.1996.2.91.
Abstract:Wavelet transform is applied to abstract of the characteristic points of CAP. A new method has been developed for detecting the start point(u) ascending branch of CAP, and Dicrotic Notch(DN) descent branch on CAP. It is discussed that the principle of the signal's singularity detectiom with wavelet transform modulus maxima points and zerocrossing points. The method is proposed to detect point u using the slope of smoothing signal at inflection point. By this method, we can achieve accurate detection result, even under serious baseline drift and strong noise.
1996, 11(2):92-96. DOI: 10.3871/j.1004-7220.1996.2.96.
Abstract:In the experimental rabbit arteriosclerosis,the changes of the cerebrovascular hemodynamic parameters(CVHP) and the relationship were observed.In arteriosclerosis group(AS group). the mean flow(Qmean), Mean velocity(Vmean), Maximal velocity(Vmax) and minimal velocity(Vmin) of the carotid blood flow and cerebrovascular compiance for zero pressure(co) were significantly decreased (p<0.05,0.01), but the values of cerebrovascular peripheral resistance(R) and characteristic impedance(Zc) were significantly increased(P<0.05 and 0.01) as compared with those in control group(C group). The values of Qmean, Vmean,and CO showed siguificant negative correlation (P<0.05,0.01) but those of R and Zc showed siguificant positive correlation (P<0.01 and 0.05) with the carotid lesions.When compared the linear equations of AS group with those of C group,the regression coefficient b of Qmean-Vmax and Qmean-R showed significant difference (P<0.01 and 0.001);the intercept a of QmeanVmean,Qmean-CO and Qmean Zc showed significant diffenence (P<0.05,0.01)
1996, 11(2):97-102. DOI: 10.3871/j.1004-7220.1996.2.102.
Abstract:The flow chamber is widely used to study the cell's mechanics behavior, especially the adhesion property. Its length and width are far larger than the height. The paper pointed out that the formula people used to calculate the shear stress was appropriate when Re was small, then gave the rational size of the flow chamber. Through an example, the paper got a result that the shear stress formula was suitable only in the middle region of the flow chamber. It provided the theoretical basis for the rational application of the flow chamber and the analysis of the cell's mechanics behavior.
1996, 11(2):103-106. DOI: 10.3871/j.1004-7220.1996.2.106.
Abstract:A new concept, design base axis of femur, is presented in this paper. The design base axis of femur,serving as the reference for the CAD of artificial hip jionts, is defined as the analogue line of the inner outline shape centers of the femur CT sections along the femur axis. The design base axis of femur is determined through the following procedures : First, the varying of the X and Y coordinates of the shape centers of the selected CT sections along the CT axis is respectively analogued; Then,the femur design base is determined according to the rules and relations of projection.
1996, 11(2):107-111. DOI: 10.3871/j.1004-7220.1996.2.111.
Abstract:For stability controlling attitude is a key to judge level of athlete in shooting. The mechanical property of controlling attitude of athlete is analysed during standing rifle shooting in this paper.We applied principle of stability and obtained optimum angle θm of controlling attitude between the trunk and horizontal line. The conclusions show lengths of trunk and forearm relate to the stability of body attitude and correspond to measuring of excellent athletes at home and abroad.
1996, 11(2):112-116. DOI: 10.3871/j.1004-7220.1996.2.116.
Abstract:According to the principle of Biomechanics, we have analyzed the dynamics of the traditionalChinese massage Rolling Manipulation. This paper is the basic theoretical part of our work. The multi-rigids biomechanical model was presented and the dynamics equations were discussed.
1996, 11(2):117-119. DOI: 10.3871/j.1004-7220.1996.2.119.
Abstract:In the paper, we studied the problem of physics equivalent intransplanting IOL,starting from the clarity and size of image and vision, on the base of combination theory of ideal optical group, among Cullstrand eye. We obtained two equivalent principle. Result of the paper was very important in the produce and transplant of IOL.