scholarly journals What Determines EP Curve Shape?

2019 ◽  
Author(s):  
Frank Xuyan Wang
Keyword(s):  
2020 ◽  
Vol 64 (1-4) ◽  
pp. 1253-1259
Author(s):  
Minghui Wang ◽  
Hongliu Yu

Clamping devices with constant force or pressure are desired in medical device, such as hemostatic forceps and the artificial sphincter, to prevent soft tissues from injures due to overloading. It is easily obtained by stretching an SMA wire. However, studies with SMA bending round bar have seldom been reported before. This paper studied constant force characteristic of C-shaped round bar with shape memory alloys. Optimization designs of the components were carried out with computational simulation. Numerical results show that the phenomenon of constant force strongly depends on contour curve shape and geometric dimensions of the C-shaped round bar of SMA component.


2021 ◽  
pp. 026461962110031
Author(s):  
Torø Graven ◽  
Clea Desebrock

This study investigated whether adding auditory angular and curved sounds to tactile angle and curve shapes – one unspecified sound to one unspecified shape – positively influences the accuracy and exploration time in recognising tactile angles and curves when experienced and inexperienced in using haptic touch. A within-participant experiment was conducted, with two groups of participants: experienced and inexperienced in using haptic touch, and with two conditions: congruous (e.g., angle shape and angular sound) and incongruous (e.g., angle shape and curved sound) tactile and auditory shape information. Adding congruous auditory angular and curved sounds to tactile angle and curve shapes positively influences the accuracy in recognising tactile angles and curves both when experienced and inexperienced in using haptic touch, and the exploration time on correct recognitions when experienced. People integrate tactile and auditory (angle; curve) shape information and this improves their proficiency in recognising tactile angles and curves.


2017 ◽  
Vol 5 (5_suppl5) ◽  
pp. 2325967117S0016
Author(s):  
Peter McEwen

Objective: Computer assisted total knee arthroplasty (CA TKA) platforms can provide detailed kinematic data that is presented in various forms including a coronal plane graphic that maps the flexion arc from full extension to deep flexion. Graphics obtained from normal tibiofemoral articulations reveal varied and complex kinematic patterns that have yet to be explained. An understanding of what drives curve variation would allow prediction of how a preoperative curve would be altered by total knee arthroplasty. Implant position could then be tailored to maintain a desirable curve or avoid an undesirable one. Methods: An articulated lower limb saw bone with a stable hip pivot was obtained. Adjustable osteotomies were created so that femoral torsion, femoral varus-valgus and tibial varus-valgus could be altered independently. The saw bone limb was registered with a CA TKA navigation system using the posterior condyles as a rotational axis. Axial and coronal plane morphology of the distal femur and coronal plane morphology of the proximal tibia were systematically altered and a kinematic curve obtained for each morphologic combination. Femoral rotational position was varied from 100 of internal torsion to 100 of external torsion in 20 increments. Similarly, femoral coronal position was varied from 20 of varus to 60 of valgus and tibial coronal position was varied from 5.50 of varus to 10 of valgus. Curves were obtained by manually flexing the joint through a full range of motion with the femoral condyles in contact with proximal tibia at all times. Results: Varying femoral rotation has no effect in full extension but drives the curve away from neutral as the knee flexes. Maximal deviation is seen at around 900 of flexion. Internal torsion drives the curve into valgus as the knee flexes and external torsion has a reciprocal effect. Varying femoral varus-valgus causes maximal deviation from neutral in full extension. Femoral varus drives the curve from varus in extension towards valgus as the knee flexes with the effect peaking in maximal flexion. Femoral valgus has a reciprocal effect. Varying tibial varus-valgus has no effect on curve shape but does move the curve either side of neutral. Complex (parabolic) curves are caused by large rotations or the opposing effects of femoral varus-valgus and femoral rotation. The modal human anatomy of slight femoral internal rotation, slight femoral valgus and slight tibial varus produces a straight neutral curve. Conclusion: Kinematic curve shape is driven by distal femoral anatomy. The typical changes made to distal femoral articular anatomy in TKA by externally rotating a neutrally orientated femoral component will bring many native curves towards neutral. Externally rotating when the preoperative curve begins neutral and drives into varus as the knee flexes will drive the curve harder into varus. Conversely, kinematic femoral placement will reconstitute the premorbid curve morphology. Which outcome is preferable has yet to be determined.


1978 ◽  
Vol 235 (2) ◽  
pp. E97 ◽  
Author(s):  
A DeLean ◽  
P J Munson ◽  
D Rodbard

Physiological and pharmacological studies of hormones, drugs, and neurotransmitters often generate families of sigmoidal dose-response curves. Optimally efficient data analysis should involve simultaneous description of all curves, rather than fitting each one individually. We have developed a general computerized method to describe the dose-response curves in terms of basal and maximal responses, ED50, and curve shape or steepness. This facile method permits rigorous statistical analysis, provides a basis for pooling of information from separate experiments, and allows one to test which characteristics are shared by various curves.


Author(s):  
Yung Ting ◽  
Gunawan Hariyanto ◽  
Bing Kuan Hou ◽  
Setiawan Ricky ◽  
Sugondo Amelia ◽  
...  

2019 ◽  
Vol 88 ◽  
pp. 458-469 ◽  
Author(s):  
Chenlei Lv ◽  
Zhongke Wu ◽  
Xingce Wang ◽  
Mingquan Zhou ◽  
Kar-Ann Toh

Author(s):  
E. Semkov ◽  
S. Ibryamov ◽  
S. Peneva ◽  
A. Mutafov

A phenomenon with a significant role in stellar evolution is the FU Orionis (FUor) type of outburst. The first three (classical) FUors (FU Ori, V1515 Cyg and V1057 Cyg) are well-studied and their light curves are published in the literature. But recently, over a dozen new objects of this type were discovered, whose photometric history we do not know well. Using recent data from photometric monitoring and data from the photographic plate archives we aim to study, the long-term photometric behavior of FUor and FUor-like objects. The construction of the historical light curves of FUors could be very important for determining the beginning of the outburst, the time to reach the maximum light, the rate of increase and decrease in brightness, the pre-outburst variability of the star. So far we have published our results for the light curves of V2493 Cyg, V582 Aur, Parsamian 21 and V1647 Ori. In this paper we present new data that describe more accurate the photometric behavior of these objects. In comparing our results with light curves of the well-studied FUors (FU Ori, V1515 Cyg and V1057 Cyg), we conclude that every object shows different photometric behavior. Each known FUor has a different rate of increase and decrease in brightness and a different light curve shape.


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