scholarly journals Efficient Body Registration Using Single-View Range Imaging and Generic Shape Templates

2020 ◽  
Vol 6 (3) ◽  
pp. 119-122
Author(s):  
Tolga-Can Çallar ◽  
Elmar Rueckert ◽  
Sven Böttger
Keyword(s):  
Body Surface ◽  
Three Dimensional ◽  
Medical Robotics ◽  
The Body ◽  
Clinical Settings ◽  
Medical Systems ◽  
Registration Method ◽  
Single View ◽  
Initial Results

AbstractComputer-aided medical systems, e.g. in the fields of medical robotics or image-based assistance, are continuously investigated to overcome human limitations concerning perception, memory or dexterity. A common requirement of such systems is the availability of a digital model describing the patient’s position and morphology during a procedure. Operational complexity and technical limitations of established 3D imaging methods leave clinical settings in need of a method for the fast acquisition of a three-dimensional body surface representation. For this purpose, we propose an unsupervised and efficient body registration pipeline based on the markerless elastic registration and completion of single-view stereo range images of the body surface with statistical parametric body shape templates. Initial results show a promising representative quality of the models generated through the registration process with submillimetric fitting accuracy and realistic surface morphology, indicating the general feasibility of our approach as an instant body registration method for automated medical and biometric applications.

MEG–MRI CO-REGISTRATION USING 3D GENERALIZED HOUGH TRANSFORM

2020 ◽  
Vol 32 (04) ◽  
pp. 2050028
Author(s):  
Sheng-Kai Lin ◽  
Rong-Chin Lo ◽  
Ren-Guey Lee
Keyword(s):  
Human Brain ◽  
Hough Transform ◽  
Three Dimensional ◽  
Measurement Tool ◽  
High Temporal Resolution ◽  
Medical Systems ◽  
Registration Method ◽  
Generalized Hough Transform ◽  
Weak Magnetic Fields ◽  
Magnetic Resonance Imaging Mri

In this paper, we propose a method to use the three-dimensional (3D) generalized Hough transform (GHT) to co-register magnetoencephalography (MEG) and magnetic resonance imaging (MRI) of a brain automatically, whose results can be used to align MRI images and MEG data accurately and efficiently. Recently, many medical devices have been developed to study the neuronal activity in the human brain. MEG is a high-temporal-resolution measurement tool to study the physiological functions of brain nerves noninvasively; whereas the MRI of the scalp, skull, and cortex of the human brain is a high-spatial-resolution tool. The proposed method combines two tools for investigating the cognitive neuroscience between the human brain structure and weak magnetic fields from two different medical systems. An accurate and automatic registration method is necessitated to improve the brain analysis processes by combining multimodal data. The conventional GHT is a well-known method for detecting two-dimensional (2D) images or locating transformed planar shapes in 2D image processes. To further improve the 2D GHT, we extended it to a 3D GHT, which can co-register MEG and MRI data automatically and accurately. Some experimental results are included to demonstrate and evaluate the error and applicability of MEG–MRI co-registration.

Specification of Destructive Influences of Selected Decontamination Mixtures on Materials Used for Construction of Chemical Specialists´ Garments Designated for Isolative Protection of the Body Surface

2018 ◽  
Vol 24 (3) ◽  
pp. 138-145
Author(s):  
Zdeněk Melichařík ◽  
Pavel Otřísal
Keyword(s):  
Body Surface ◽  
Armed Forces ◽  
Selective Decontamination ◽  
Butyl Rubber ◽  
The Body ◽  
Effective Protection ◽  
Materials Used ◽  
Protective Garment ◽  
Repeated Contact

Abstract A paper deals with the influence of selective decontamination mixtures established in the Czech Armed Forces on an isolative protective foil used to the construction of anti-gas protective garment marked as OPCH-05. Presented information are a part of thematically focused works aimed to study of influences of all established decontamination mixtures on the Czech Armed Forces Chemical Corps´ garments of anti-gas protection. The quality of provided the Czech Armed Forces Chemical Corps´ specialists isolative protection is limited with the existence of several aspects which significantly determine with their materials equipment. For providing isolative protection of the body surface are used such as protective garments which are the hermetic type and they are constructively solved with the employment of the butyl-rubber polymeric mixture. The effective protection of the body surface must be guaranteed even within the presumption of a repeated contact with decontamination mixtures

Calculation of Nonlifting Potential Flow About Arbitrary Three-Dimensional Bodies

1964 ◽  
Vol 8 (04) ◽  
pp. 22-44 ◽  
Author(s):  
John L. Hess ◽  
A. M. O. Smith
Keyword(s):  
Body Surface ◽  
Potential Flow ◽  
Fluid Velocity ◽  
Normal Component ◽  
Three Dimensional ◽  
Analytic Solutions ◽  
The Body ◽  
Algebraic Equations ◽  
Source Density ◽  
Linear Algebraic Equations

A general method is described for calculating, with the aid of an electronic computer, the incompressible potential flow about arbitrary, nonlifting, three-dimensional bodies. The method utilizes a source density distribution on the surface of the body and solves for the distribution necessary to make the normal component of fluid velocity zero on the boundary. Plane quadrilateral surface elements are used to approximate the body surface, and the integral equation for the source density is replaced by a set of linear algebraic equations for the values of the source density on the quadrilateral elements. When this set of equations has been solved, the flow velocity both on and off the body surface is calculated. After the basic ideas and equations have been derived end discussed, the accuracy of the method is exhibited by means of comparisons with analytic solutions, and its usefulness is shown by comparing calculated pressure distributions with experimental data. Some of the design problems to which the method has been applied are also presented, to indicate the variety of flow situations that can be calculated by this approach.

Seeding from silica-reinforced lysozyme crystals for neutron crystallography

2018 ◽  
Vol 74 (12) ◽  
pp. 1200-1207 ◽  
Author(s):  
Jose A. Gavira ◽  
Mayte Conejero-Muriel ◽  
José Manuel Delgado-López
Keyword(s):  
Crystal Structure ◽  
Structural Model ◽  
Three Dimensional ◽  
The Body ◽  
Protein Crystals ◽  
Direct Influence ◽  
Scanning Calorimetry ◽  
Wide Range ◽  
Lysozyme Crystals

The fragility of protein crystals plays an important role in the final quality of the diffraction data and therefore that of the derived three-dimensional structural model. The growth of protein crystals in gels of various natures has been shown to overcome this problem, facilitating the manipulation of the crystals; this is probably owing, amongst other factors, to the incorporation of the gel fibres within the body of the crystal. In this study, lysozyme crystals were grown in silica gel at a wide range of concentrations of up to 22%(v/v) to quantitatively determine the amount of gel incorporated into the crystal structure by means of thermogravimetric analysis. The interaction between the silica fibres and the lysozyme molecules within the crystals was also investigated using Raman spectroscopy and the direct influence on the crystalline protein stability was analysed using differential scanning calorimetry. Finally, the benefits of the use of gel-grown crystals to overgrow protein crystals intended for neutron diffraction are highlighted.

scholarly journals The Influence of X-Factor (Trunk Rotation) and Experience on the Quality of the Badminton Forehand Smash

2016 ◽  
Vol 53 (1) ◽  
pp. 9-22 ◽  
Author(s):  
Zhao Zhang ◽  
Shiming Li ◽  
Bingjun Wan ◽  
Peter Visentin ◽  
Qinxian Jiang ◽  
...  
Keyword(s):  
Motion Capture ◽  
Teaching And Learning ◽  
Three Dimensional ◽  
Biomechanical Model ◽  
Kinematic Chain ◽  
The Body ◽  
Trunk Rotation ◽  
Preparation Phase ◽  
Full Body

AbstractNo existing studies of badminton technique have used full-body biomechanical modeling based on three-dimensional (3D) motion capture to quantify the kinematics of the sport. The purposes of the current study were to: 1) quantitatively describe kinematic characteristics of the forehand smash using a 15-segment, full-body biomechanical model, 2) examine and compare kinematic differences between novice and skilled players with a focus on trunk rotation (the X-factor), and 3) through this comparison, identify principal parameters that contributed to the quality of the skill. Together, these findings have the potential to assist coaches and players in the teaching and learning of the forehand smash. Twenty-four participants were divided into two groups (novice, n = 10 and skilled, n = 14). A 10-camera VICON MX40 motion capture system (200 frames/s) was used to quantify full-body kinematics, racket movement and the flight of the shuttlecock. Results confirmed that skilled players utilized more trunk rotation than novices. In two ways, trunk rotation (the X-factor) was shown to be vital for maximizing the release speed of the shuttlecock – an important measure of the quality of the forehand smash. First, more trunk rotation invoked greater lengthening in the pectoralis major (PM) during the preparation phase of the stroke which helped generate an explosive muscle contraction. Second, larger range of motion (ROM) induced by trunk rotation facilitated a whip-like (proximal to distal) control sequence among the body segments responsible for increasing racket speed. These results suggest that training intended to increase the efficacy of this skill needs to focus on how the X-factor is incorporated into the kinematic chain of the arm and the racket.

Three-dimensional interaction between uniform current and a submerged horizontal cylinder in an ice-covered channel

2021 ◽  
Vol 928 ◽  
Author(s):  
Y.F. Yang ◽  
G.X. Wu ◽  
K. Ren
Keyword(s):  
Green Function ◽  
Circular Cylinder ◽  
Body Surface ◽  
Velocity Potential ◽  
Three Dimensional ◽  
Ice Sheet ◽  
The Body ◽  
Thin Elastic Plate ◽  
Uniform Current ◽  
The Green Function

The problem of interaction of a uniform current with a submerged horizontal circular cylinder in an ice-covered channel is considered. The fluid flow is described by linearized velocity potential theory and the ice sheet is treated as a thin elastic plate. The potential due to a source or the Green function satisfying all boundary conditions apart from that on the body surface is first derived. This can be used to derive the boundary integral equation for a body of arbitrary shape. It can also be used to obtain the solution due to multipoles by differentiating the Green function with its position directly. For a transverse circular cylinder, through distributing multipoles along its centre line, the velocity potential can be written in an infinite series with unknown coefficients, which can be determined from the impermeable condition on a body surface. A major feature here is that different from the free surface problem, or a channel without the ice sheet cover, this problem is fully three-dimensional because of the constraints along the intersection of the ice sheet with the channel wall. It has been also confirmed that there is an infinite number of critical speeds. Whenever the current speed passes a critical value, the force on the body and wave pattern change rapidly, and two more wave components are generated at the far-field. Extensive results are provided for hydroelastic waves and hydrodynamic forces when the ice sheet is under different edge conditions, and the insight of their physical features is discussed.

The impact of 60-minute swimming training on the quality of body posture and the level of balance of young adults

2019 ◽  
Vol 4 (3) ◽  
pp. 1-6
Author(s):  
Dżesika Aksamit ◽  
Tomasz Sidor ◽  
Adrian Gądek ◽  
Agnieszka Jankowicz-Szymańska
Keyword(s):  
Thoracic Kyphosis ◽  
Three Dimensional ◽  
Frontal Plane ◽  
The Body ◽  
Body Posture ◽  
Swimming Training ◽  
Significance Level ◽  
Before And After ◽  
The Impact

Introduction: Postural abnormalities are common in every age group. They often involve discomfort or pain. Unfortunately, specialist posture correcting body postures are almost exclusively for pre-school and school children. There is a widespread belief in the beneficial effects of swimming on the body posture. Some even think that swimming can replace corrective exercises. The aim of the study was to evaluate the changes in the quality of body posture and body balance under the influence of 60-minute intensive swimming training in people aged 20-22 years, whose level of swimming skills was determined as average. Material and methods: The study was conducted on a group of 9 people, students of the State Higher Vocational School in Tarnów. Ultrasonic device Zebris Pointer was used for three-dimensional assessment of body posture. The position of the shoulder and iliac girdle, the shape of the spine, the inclination of the sacrum bone and the inclination of the body in the sagittal and frontal plane were analyzed. The test was repeated before and after the one-hour lecture and before and after one-hour, intensive classes at the swimming pool. The results were developed in the Statistika v10 program. Descriptive statistics, non-parametric Friedman test and Kruskal posthoc test were used. The significance level α = 0.05 was assumed. Results: There was a statistically significant increase in pelvic rotation under the influence of swimming training. There was also a slight deterioration of the spine position in the frontal plane. Exercises improving swimming in the classic style did not affect the depth of thoracic kyphosis and lumbar lordosis. After 60 minutes spent in a relaxed sitting position, deepening thoracic kyphosis was observed. However, this change was not statistically significant. Conclusions: It is not recommended to treat swimming as a substitute for corrective gymnastics. Intensive swimming training can exacerbate existing body posture errors in people who are just improving their swimming technique.

Flow past wing-body junctions

1984 ◽  
Vol 144 ◽  
pp. 191-215 ◽  
Author(s):  
F. T. Smith ◽  
J. Gajjar
Keyword(s):  
Body Surface ◽  
Three Dimensional ◽  
Leading Edge ◽  
The Body ◽  
Two Dimensional ◽  
Three Dimensional Flow ◽  
Flow Response ◽  
Flow Past ◽  
Short Wing ◽  
Corner Layer

The three-dimensional laminar flow past a junction formed by a thin wing protruding normally from a locally flat body surface is considered for wings of finite span but short or long chord. The Reynolds number is taken to be large. The leading-edge interaction for a long wing has the triple-deck form, with the pressure due to the wing thickness forcing a three-dimensional flow response on the body surface alone. The same interaction describes the flow past an entire short wing. Linearized solutions are presented and discussed for long and short two-dimensional wings and for certain three-dimensional wings of interest. The trailing-edge interaction for a long wing is different, however, in that the three-dimensional motions on the wing and on the body are coupled together and in general the coupling is nonlinear. Linearized properties are retrieved only for reduced chord lengths. The overall flow structure for a long wing is also discussed, including the traditional three-dimensional corner layer, which is shown to have an unusual singular starting form near the leading edge. Qualitative comparisons with experiments are made.

scholarly journals RANGES OF ADMISSIBLE VALUES OF GEOMETRIC PARAMETERS OF A WHEELED JUMPING ROBOT

2018 ◽  
Vol 22 (2) ◽  
pp. 76-84 ◽  
Author(s):  
L. Yu. Vorochaeva ◽  
А. V. Malchikov ◽  
S. I. Savin
Keyword(s):  
Three Dimensional ◽  
The State ◽  
The Body ◽  
Geometric Parameters ◽  
Mutual Arrangement ◽  
Combined System ◽  
Three Dimensional Models ◽  
Jumping Robot ◽  
State Of The Environment

The use of robots to perform tasks traditionally assigned to people leads to an improvement in the quality of their implementation, a reduction in the costs and risks associated with them. A typical example of this is the task of monitoring and examining hard-to-reach areas. The introduction of robots to solve such problems could bring a significant economic and social effect, allowing the automation of a number of complex, time-consuming and potentially dangerous tasks, such as the compilation and updating of maps and three-dimensional models of emergency sites, the collection of data on the state of the environment in areas, exposed to biological or radiation contamination, continuous monitoring of the state of the environment and sampling of air and soil. The paper considers one of the possible designs of such robots: a wheeled jumping robot, which consists of an acceleration module for jumping(used to for overcome obstacles), and a wheel platform, which allows the robot to use wheeled locomotion when moving over the surfaces with small irregularities. The advantages of such a combined system include higher maneuverability and higher speeds of movement, as well as a wider functionality in terms of the range of terrains suitable for movement. For this robot, a design scheme has been developed and two critical positions of the device are identified, which allows to formulate conditions that impose limitations on the geometric parameters of the body, the acceleration module and the wheels, and their mutual arrangement, in order to ensure operation of the robot in two modes: wheeled and jumping. The results of modeling are presented in the form of permissible ranges for the length and height of the body, as well as the maximum length of the acceleration module from the radius of the wheels and the location of their installation point, taking into account the capability of the acceleration module to do a complete rotation within the robot’s frame .

A Generalized Wagner Method for Three-Dimensional Slamming

2005 ◽  
Vol 49 (04) ◽  
pp. 279-287
Author(s):  
O. M. Faltinsen ◽  
M. Chezhian
Keyword(s):  
Free Surface ◽  
Body Surface ◽  
Surface Condition ◽  
Three Dimensional ◽  
Water Entry ◽  
The Body ◽  
Experimental Results ◽  
Vertical Force ◽  
Free Surface Condition ◽  
Drop Tests

Impact between the water and ship, that is, slamming, can cause important global and local effects. A numerical method has been applied to predict water entry loads on three-dimensional bodies. The problem is solved as an initial value problem using the boundary element method. The Green second identity is used to represent the velocity potential as a distribution of Rankine sources and dipoles over the body surface and free surface. The problem is stepped up in time using the information from the boundary conditions. The kinematic free-surface condition is used to determine the intersection between the body surface and free surface at each time step. The exact body boundary condition is used, whereas the dynamic free-surface condition, φ = 0, is approximated on to a horizontal line and not on the exact free-surface profile. The approach presented by Zhao et al (1996) for two-dimensional water entry problems was extended to arbitrary three-dimensional bodies in this presented work. An idealized shape, which consists of cylindrical mid-body and hemispherical ends, was studied. The wetted body surface is calculated with great detail and is considered to be more important than the free-surface elevation away from the body. Drop tests have been carried out to verify and validate the numerical simulation. The effect of the angle between the free surface and the body surface has also been studied. The agreement between theory and experiments is good, and the effect of three-dimensionality is documented. The presented computational method is found to be robust for engineering use and computationally less demanding. The experimental results for vertical force have a strong oscillatory nature, and this has been analyzed using a simplified hydroelastic model. The hydroelastic model gives reasonable representation of the dynamic oscillations found in the vertical force. Reasons for the observed deviations between the numerical and the experimental results are documented. Recommendations for conducting drop tests with minimal dynamic effects are also presented.

Sign in / Sign up

Export Citation Format

Share Document