189. Evaluation of coronal alignment from the skull using the novel orbital-coronal vertical axis line

2021 ◽  
Vol 21 (9) ◽  
pp. S96
Author(s):  
Scott L. Zuckerman ◽  
Christopher Lai ◽  
Yong Shen ◽  
Mena Kerolus ◽  
Ian Buchanan ◽  
...  
Keyword(s):  
Vertical Axis ◽  
The Novel ◽  
Coronal Alignment

Changes in temporal binding related to decreased vestibular input

2012 ◽  
Vol 25 (0) ◽  
pp. 107
Author(s):  
Nai-Yuan Nicholas Chang ◽  
Alex K. Malone ◽  
Timothy E. Hullar
Keyword(s):  
Vertical Axis ◽  
Normal Subjects ◽  
Head Movements ◽  
Whole Body ◽  
The Novel ◽  
Vestibular Input ◽  
Temporal Binding ◽  
Sensory Stimuli ◽  
Vestibular Hypofunction ◽  
Temporal Binding Window

Imbalance among patients with vestibular hypofunction has been related to inadequate compensatory eye movements in response to head movements. However, symptoms of imbalance might also occur due a temporal mismatch between vestibular and other balance-related sensory cues. This temporal mismatch could be reflected in a widened temporal binding window (TBW), or the length of time over which simultaneous sensory stimuli may be offset and still perceived as simultaneous. We hypothesized that decreased vestibular input would lead to a widening of the temporal binding window. We performed whole-body rotations about the earth-vertical axis following a sinusoidal trajectory at 0.5 Hz with a peak velocity of 60°/s in four normal subjects. Dichotic auditory clicks were presented through headphones at various phases relative to the rotations. Subjects were asked to indicate whether the cues were synchronous or asynchronous and the TBW was calculated. We then simulated decreased vestibular input by rotating at diminished peak velocities of 48, 24 and 12°/s in four normal subjects. TBW was calculated between ±1 SD away from the mean on the psychometric curve. We found that the TBW increases as amplitude of rotation decreases. Average TBW of 251 ms at 60°/s increased to 309 ms at 12°/s. This result leads to the novel conclusion that changes in temporal processing may be a mechanism for imbalance in patients with vestibular hypofunction.

Performance Evaluation of Novel Spline-Curved Blades of a Vertical Axis Wind Turbine Based on the Savonius Concept

2016 ◽  
Author(s):  
Michele Mari ◽  
Mauro Venturini ◽  
Asfaw Beyene
Keyword(s):  
Fluid Dynamic ◽  
National Laboratory ◽  
Sandia National Laboratory ◽  
Vertical Axis ◽  
Cfd Analysis ◽  
The Novel ◽  
Turbulent Model ◽  
Vertical Axis Wind Turbine ◽  
Laboratory Results ◽  
Central Shaft

In this study, we present the results of a two-dimensional fluid-dynamic simulation of novel rotor geometry with spline function which is derivative of the traditional S-shape Savonius blade. A Computational Fluid Dynamic (CFD) analysis is conducted using the Spalart-Allmaras turbulent model, validated using experimental data released by Sandia National Laboratory. Results are presented in terms of dimensionless torque and power coefficients, assuming a wind speed of 7 m/s and height and rotor diameter of 1 m. Furthermore, analysis of the forces acting on the rotor is conducted by evaluating frontal and side forces on each blade, and the resultant force acting on the central shaft. A qualitative representation of the vorticity around the traditional and spline rotor is shown to prove that the novel blade is more “flow-friendly”, thus the air flow is less turbulent through the rotor. Finally, energy conversion capability of the Savonius turbines is estimated in parametric form for both the traditional and spline-curved geometry.

A Novel Geometry for Vertical Axis Wind Turbines Based on the Savonius Concept

2017 ◽  
Vol 139 (6) ◽  
Author(s):  
Michele Mari ◽  
Mauro Venturini ◽  
Asfaw Beyene
Keyword(s):  
Fluid Dynamic ◽  
National Laboratory ◽  
Sandia National Laboratory ◽  
Vertical Axis ◽  
The Novel ◽  
Turbulent Model ◽  
Vertical Axis Wind Turbines ◽  
Laboratory Results ◽  
Flow Through ◽  
Central Shaft

In this study, we present the results of a two-dimensional fluid-dynamic simulation of novel rotor geometry with spline function which is derivative of the traditional S-shape Savonius blade. A computational fluid dynamic (CFD) analysis is conducted using the Spalart–Allmaras turbulent model, validated using experimental data released by Sandia National Laboratory. Results are presented in terms of dimensionless torque and power coefficients, assuming a wind speed of 7 m/s and height and rotor diameter of 1 m. Furthermore, analysis of the forces acting on the rotor is conducted by evaluating frontal and side forces on each blade, and the resultant force acting on the central shaft. A qualitative representation of the vorticity around the traditional and spline rotor is shown to prove that the novel blade allows less turbulent flow through the rotor.

scholarly journals Comparison with Navigation of a Novel Three-Step Technique for Improving Accuracy of the Distal Femoral Resection during Conventional TKA: A Case–Control Study

2021 ◽  
Author(s):  
Arun B. Mullaji ◽  
Ahmed A. Khalifa ◽  
Gautam Shetty ◽  
Harshad Thakur
Keyword(s):  
Femoral Component ◽  
Computer Navigation ◽  
Varus Deformity ◽  
Conventional Technique ◽  
The Novel ◽  
Coronal Alignment ◽  
Component Alignment ◽  
Term Survival ◽  
Significant Difference ◽  
The Mean

AbstractCorrect placement of the femoral component in the coronal plane during primary total knee arthroplasty (TKA) is related to long-term survival. The aim of this radiographic study was to determine the accuracy of a novel three-step technique for improving the accuracy of the distal femoral cut during conventional technique and compare it with computer navigation during TKA. A total of 458 TKAs were retrospectively analyzed (178 conventional TKAs with the novel technique and 280 navigated TKAs) for postoperative femoral component coronal alignment and compared between the two groups. Mean femoral component coronal alignment was not significantly different (p = 0.314) between the two groups. There was no significant difference in the mean femoral component coronal alignment between varus and valgus knees. The number of outliers (90 ± 3 degrees) for femoral component coronal alignment was not significantly different between the two groups when assessed separately for varus and valgus deformities. The mean value of femoral component alignment using the conventional technique in knees with varus deformity <10 degrees was 88.8 degrees, in knees with varus deformity 10 to 20 degrees was 89.4 degrees, and in those with varus deformity >20 degrees was 90.2 degrees. Femoral component alignment in knees with varus <10 degrees was significantly different from those >20 degrees (p = 0.006); there was no significant difference between knees with varus <10 degrees and those with 10 to 20 degrees varus (p = 0.251), nor between 10 and 20 degrees varus knees and those with varus >20 degrees (p = 0.116). Using the novel three-step technique during conventional TKA to perform the distal femoral cut can help achieve femoral component coronal alignment comparable to the navigation technique.

scholarly journals Conceptological analysis of artistic space in novel „The Time Machine" by H. G. Wells (translated into Russian)

2020 ◽  
pp. 151-160
Author(s):  
E. V. Minaieva ◽  
Keyword(s):  
Complex System ◽  
Vertical Axis ◽  
The Novel ◽  
Time Machine ◽  
Binary Opposition ◽  
The World ◽  
Different Levels

The article discusses the features of modeling artistic space in novel The Time Machine, by H. G. Wells through a complex system of concepts top, bottom, fear, darkness, light. The constant interaction of these concepts leads to increased permeability of their boundaries, to a continuous exchange of conceptual features. The artistic space in the novel by H. G. Wells has a pronounced vertical character. We have identified the universal axis of top-bottom concepts in the artistic space and analyzed it. Movement along the vertical axis of the up and down concepts is carried out throughout the novel. In the novel The Time Machine, the features of the top concept become blurred, as they are overlaid with the features of the bottom concept. In the novel by H. G. Wells, the emotive concept of fear forms a fusion with the concepts of darkness and light. Fear unites different levels of the novel's artistic space. The binary concepts of darkness and light actively model the artistic space in novel The Time Machine. These concepts are closely related to the binary opposition of top-bottom concepts. In addition, they perform ontological, epistemological, axiological and aesthetic functions. The study of the features of artistic space in the novel The Time Machine opens up opportunities for further research of the artistic model of the world by H. G. Wells and the problems of modeling artistic space in the literature.

A Hybrid Tracked-Wheeled Multi-Directional Mobile Robot

2019 ◽  
Vol 11 (4) ◽  
Author(s):  
Pinhas Ben-Tzvi ◽  
Wael Saab
Keyword(s):  
Mobile Robot ◽  
High Speed ◽  
Longitudinal Direction ◽  
Vertical Axis ◽  
The Novel ◽  
Lateral Direction ◽  
Hybrid Combination ◽  
Inclined Surfaces ◽  
Translational Joint ◽  
Novel Design

This paper presents the novel design and integration of a mobile robot with multi-directional mobility capabilities enabled via a hybrid combination of tracks and wheels. Tracked and wheeled locomotion modes are independent from one another, and are cascaded along two orthogonal axes to provide multi-directional mobility. An actuated mechanism toggles between these two modes for optimal mobility under different surface-traction conditions, and further adds an additional translational axis of mobility. That is, the robot can move in the longitudinal direction via the tracks on rugged terrain for high traction, in the lateral direction via the wheels on smooth terrain for high-speed locomotion, and along the vertical axis via the translational joint. Additionally, the robot is capable of yaw axis mobility using differential drives in both tracked and wheeled modes of operation. The paper presents design and analysis of the proposed robot along with a dynamic stabilization algorithm to prevent the robot from tipping over while carrying an external payload on inclined surfaces. Experimental results using an integrated prototype demonstrate multi-directional capabilities of the mobile platform and the dynamic stability algorithm to stabilize the robot while carrying various external payloads on inclined surfaces measuring up to 2.5 kg and 10 deg, respectively.

scholarly journals A novel integrated global coronal aligner helps prevent post-operative standing coronal imbalance in adult spinal deformity patients fused to pelvis: technical notes and preliminary results

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jiandang Zhang ◽  
Pengfei Chi ◽  
Junyao Cheng ◽  
Zheng Wang
Keyword(s):  
Regression Analysis ◽  
Spinal Deformity ◽  
Odds Ratio ◽  
Adult Spinal Deformity ◽  
Deformity Correction ◽  
The Novel ◽  
Coronal Alignment ◽  
Level Of Evidence ◽  
Coronal Balance ◽  
Coronal Imbalance

Abstract Background Chieving postoperative coronal balance in adult spinal deformity correction surgeries can be challenging. Even with T square rod technique, there were still some cases with good intraoperative coronal alignment but unsatisfactory post-operative standing coronal imbalance. Thus, the novel techniques to obtain global coronal balance are still in great needs. The purpose of this study was to describe a novel integrated global coronal aligner (IGCA) and evaluate its efficacy on avoidance of post-operative coronal imbalance in adult spinal deformity patients fused to pelvis. Methods A detailed description of IGCA technique was presented. 52 ASD patients fused to pelvis were divided into two groups (IGCA group, n = 27; and non-IGCA group, n = 25) according to whether intraoperative IGCA was used or not. Preoperative demographics and postoperative outcomes were compared. Results There were no significant differences regarding coronal balance difference (CBD) and imbalance/balance ratio between IGCA and non-IGCA groups preoperatively. After surgery, CBD in IGCA group was significantly improved from 24.7 ± 20.3 mm preoperatively to 12.6 ± 6.4 mm postoperatively (t = 3.185 p = 0.004), and imbalance/balance ratio decreased significantly from 55.6% (15/27) preoperatively to 11.1% (3/27) postoperatively (χ2 = 12.000, p = 0.001), while CBD and imbalance/balance ratio in non-IGCA group were not significantly improved. Compared to non-IGCA group, the amount of correction in CBD was significantly larger in IGCA group (t = 3.274, P = 0.002), and imbalance/balance ratio in IGCA group was significantly lowered (χ2 = 8.606 p = 0.003). Further logistic regression analysis revealed IGCA technique was associated with increased odds ratio for postoperative coronal balance (odds ratio: 7.385; 95% confidence interval 1.760–30.980; P = 0.006). Conclusions The novel intraoperative IGCA technique could help improve CBD and reduce imbalance/balance ratio. It could help prevent post-operative coronal imbalance in adult spinal deformity patients fused to pelvis. Level of evidence 3

scholarly journals The Parameters Affect on Power Coefficient Vertical Axis Wind Turbine

2012 ◽  
Vol 13 (1) ◽  
Author(s):  
Ahmed Y. Qasim ◽  
Ryspek Usubamatov ◽  
Zuraidah M. Zain ◽  
Ghulam Abdul Quad
Keyword(s):  
Drag Coefficient ◽  
Wind Turbine ◽  
Vertical Axis ◽  
Power Coefficient ◽  
The Novel ◽  
Vertical Axis Wind Turbine ◽  
Four Frames ◽  
Different Types ◽  
Variable Wind ◽  
Novel Design

ABSTRACT: This study describes the design of a special type of vertical axis rotor wind turbine with moveable vertically positioned vanes. The novel design increases the torque in the left side of the wind turbine by increasing the drag coefficient. It also reduces the negative torque of the frame which rotates contrary to the wind in the other side. Two different types of models, having different vane shapes (flat vane and cavity shaped vane), were fabricated. Each type consisted of two models with varying number of frames (three and four frames). The models were tested in a wind tunnel with variable wind speed in order to understand the effect of shape, weight, and number of frames on the power coefficient of the wind turbine. ABSTRAK: Di dalam kajian ini, rotor turbin angin berpaksi vertikel sebagai rangka khusus telah direkabentuk dengan lokasi vertikel mudahalih oleh bilah kipas. Rekabentuk ini meningkatkan tork di bahagian kiri turbin angin dengan meningkatkan pekali seretan dan mengurangkan tork negatif rangka yang berputar berlawanan dengan angin pada bahagian lain. Dua jenis model berbentuk berlainan telah difabrikasi (bilah kipas rata dan bilah kipas berbentuk kaviti), dengan setiap jenis mempunyai dua model dengan bilangan rangka yang berlainan (berangka tiga dan berangka empat). Model-model telah diuji di dalam terowong angin dengan kelajuan angin yang berbeza bagi mendapatkan kesan rekabentuk, berat dan bilangan rangka ke atas pekali kuasa.KEYWORDS: design; wind turbine; drag coefficient; vane

The novel steroidal glycoside from the dried bulb of Allium Macrostemon Bunge inhibits platelet activation

2010 ◽  
Vol 34 (8) ◽  
pp. S33-S33
Author(s):  
Wenchao Ou ◽  
Haifeng Chen ◽  
Yun Zhong ◽  
Benrong Liu ◽  
Keji Chen
Keyword(s):  
Platelet Activation ◽  
The Novel ◽  
Steroidal Glycoside ◽  
Allium Macrostemon
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