scholarly journals Research on Body Type Correction of FINA Diving Difficulty Coefficient Based on Rigid Body System

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Su Zhang ◽  
Wen Xiang ◽  
Guozhong Zou
Keyword(s):  
Body Shape ◽  
Calculation Model ◽  
Correction Coefficient ◽  
Dynamics Model ◽  
Body Type ◽  
Body Dynamics ◽  
Shape Correction ◽  
Original Calculation ◽  
Structural Parts ◽  
The Relationship

In order to reduce the influence of athlete’s body shape on the difficulty coefficient of diving, a more reasonable calculation method of body shape correction coefficient is proposed based on the original calculation rules of diving difficulty coefficient. First, the composition of the original diving difficulty coefficient and influencing factors is analyzed and the relationship between the various structural parts is fully clarified. Second, a coupled nonrigid body dynamics model is established and a 2-body model is used to simulate complex diving actions, and it is concluded that diving time is positively correlated with body shape. Finally, the air movement part and the water entry part of diving are discussed separately, the calculation model of the difficulty coefficient of body shape correction is established, and the original difficulty coefficient is corrected. The results show that the difficulty coefficient of each movement is obviously increased. This effectively avoids the influence of body shape on the diving difficulty coefficient.

High torque realization of the stepping over gait for a humanoid robot

2020 ◽  
Vol 47 (4) ◽  
pp. 473-487
Author(s):  
Keqiang Bai ◽  
Yunzhi Luo ◽  
Guanwu Jiang ◽  
Guoli Jiang ◽  
Li Guo
Keyword(s):  
Design Methodology ◽  
Humanoid Robot ◽  
Joint Angle ◽  
Stability Margin ◽  
Whole Body ◽  
Dynamics Model ◽  
Content Type ◽  
Body Dynamics ◽  
High Torque ◽  
The Relationship

Purpose This paper aims to propose a pulsing type joint servo driver-based obstacle surmounting method for a humanoid robot according to the whole-body dynamics model, which fully takes into account the relationship between the whole-body stability margin and instantaneous torque. Design/methodology/approach First, the authors designed a new practical instantaneous large torque strategy for a pulsing type joint servo driver by modeling the whole-body dynamics of the humanoid robot. The work also considered joint angle planning based on the dynamic model for crossing obstacles. Second, in the simulation and experimentation, the instantaneous torque of the driver is used to realize successful crossing of obstacles by the humanoid robot. This verifies the correctness of the whole-body dynamics model and the feasibility of the method for crossing obstacles. Findings The experimental data and results are described and analyzed, showing that the proposed method is feasible and effective through simulation and implementation. Originality/value The main contribution is the humanoid robot’s actuation control technology and humanoid action realization, which could be used for squatting and moving heavy objects to help a humanoid robot adapt effectively.

scholarly journals Engine Malfunctioning Conditions Identification through Instantaneous Crankshaft Torque Measurement Analysis

2021 ◽  
Vol 11 (8) ◽  
pp. 3522
Author(s):  
Konstantinos-Marios Tsitsilonis ◽  
Gerasimos Theotokatos
Keyword(s):  
Operating Conditions ◽  
Cylinder Pressure ◽  
Dynamics Model ◽  
Engine Model ◽  
Measurement Analysis ◽  
Start Of Injection ◽  
Rate Of Heat Release ◽  
Relationship Of ◽  
Diagnostic Measurement ◽  
The Relationship

In this study a coupled thermodynamics and crankshaft dynamics model of a large two-stroke diesel engine was utilised, to map the relationship of the engine Instantaneous Crankshaft Torque (ICT) with the following frequently occurring malfunctioning conditions: (a) change in Start of Injection (SOI), (b) change in Rate of Heat Release (RHR), (c) change in scavenge air pressure, and (d) blowby. This was performed using frequency analysis on the engine ICT, which was obtained through a series of parametric runs of the coupled engine model, under the various malfunctioning and healthy operating conditions. This process demonstrated that engine ICT can be successfully utilised to identify the distinct effects of malfunctions (c) or (d), as they occur individually in any cylinder. Furthermore by using the same process, malfunctions (a) and (b) can be identified as they occur individually for any cylinder, however there is no distinct effect on the engine ICT among these malfunctions, since their effect on the in-cylinder pressure is similar. As a result, this study demonstrates the usefulness of the engine ICT as a non-intrusive diagnostic measurement, as well as the benefits of malfunctioning conditions mapping, which allows for quick and less resource intensive identification of engine malfunctions.

scholarly journals Influence of Selected Model Parameters on the Electromagnetic Levitation Melting Efficiency

2021 ◽  
Vol 11 (9) ◽  
pp. 3827
Author(s):  
Blazej Nycz ◽  
Lukasz Malinski ◽  
Roman Przylucki
Keyword(s):  
Electromagnetic Levitation ◽  
Optimization Methods ◽  
Calculation Model ◽  
Model Parameters ◽  
Starting Point ◽  
Low Efficiency ◽  
The Relationship ◽  
Reactive Metals ◽  
Electromagnetic Levitation Melting ◽  
Metal Melting

The article presents the results of multivariate calculations for the levitation metal melting system. The research had two main goals. The first goal of the multivariate calculations was to find the relationship between the basic electrical and geometric parameters of the selected calculation model and the maximum electromagnetic buoyancy force and the maximum power dissipated in the charge. The second goal was to find quasi-optimal conditions for levitation. The choice of the model with the highest melting efficiency is very important because electromagnetic levitation is essentially a low-efficiency process. Despite the low efficiency of this method, it is worth dealing with it because is one of the few methods that allow melting and obtaining alloys of refractory reactive metals. The research was limited to the analysis of the electromagnetic field modeled three-dimensionally. From among of 245 variants considered in the article, the most promising one was selected characterized by the highest efficiency. This variant will be a starting point for further work with the use of optimization methods.

Simulation of Valve Position Feedback Mechanism Based on Pro/E and ADAMS

2014 ◽  
Vol 721 ◽  
pp. 244-248
Author(s):  
You Jun Fan ◽  
Fei Li ◽  
Hua Tian Zhao
Keyword(s):  
Feedback Mechanism ◽  
Dynamics Model ◽  
Joint Simulation ◽  
Force And Motion ◽  
Motion State ◽  
Position Feedback ◽  
Displacement Angle ◽  
Valve Position ◽  
Relationship Of ◽  
The Relationship

In traditional valve position feedback mechanism design, it is tested repeatedly and improvement after processing prototype, the process is complex and workload. Using Pro/E and ADAMS, the overall mechanical structure of the valve position feedback mechanism for joint simulation, and an analysis of the kinematics and dynamics model, simplified the design process of the repeated calculation, get the relationship of stem displacement-angle between gear, gear meshing force and motion state of the stem, the simulation value compared with the theoretical value, tallies with the data and shows that the simulation is reasonable.

Research on the hydrographic survey cycle for updating navigational charts

2021 ◽  
pp. 1-13
Author(s):  
Jing Duan ◽  
Xiaoxia Wan ◽  
Jianan Luo
Keyword(s):  
Neural Network ◽  
Bp Neural Network ◽  
Calculation Model ◽  
Impact Factors ◽  
Factors Affecting ◽  
Material Resources ◽  
Hydrographic Survey ◽  
Survey Planning ◽  
The Impact ◽  
The Relationship

Abstract Due to the vast ocean area and limited human and material resources, hydrographic survey must be carried out in a selective and well-planned way. Therefore, scientific planning of hydrographic surveys to ensure the effectiveness of navigational charts has become an urgent issue to be addressed by the hydrographic office of each coastal state. In this study, a reasonable calculation model of hydrographic survey cycle is established, which can be used to make the plan of navigational chart updating. The paper takes 493 navigational charts of Chinese coastal ports and fairways as the research object, analyses the fundamental factors affecting the hydrographic survey cycle and gives them weights, proposes to use the BP neural network to construct the relationship between the cycle and the impact factors, and finally establishes a calculation model of the hydrographic survey cycle. It has been verified that the calculation cycle of the model is effective, and it can provide reference for hydrographic survey planning and chart updating, as well as suggestions for navigation safety.

The relationship between men’s peer and social media muscularity ideal discrepancies and body satisfaction

2020 ◽  
Vol 37 (5) ◽  
pp. 1534-1553
Author(s):  
Mark Allen Flynn ◽  
Emily Cotchett ◽  
Linda Lin
Keyword(s):  
Social Networking Sites ◽  
Body Satisfaction ◽  
Body Type ◽  
Adult Men ◽  
Ideal Body ◽  
Ideal Discrepancy ◽  
Self Discrepancy ◽  
The Impact ◽  
The Relationship ◽  
Body Perceptions

Previous studies have shown that discrepancy between perceptions of one’s actual body type and the ideal bodies of their peers is an important factor for one’s body satisfaction. However, there is a lack of research assessing the formation of media-specific discrepancies, the impact of different types of discrepancies together, and discrepancies in adult men. The current study explored the impact of adult men’s actual and ideal body perceptions on their body satisfaction. Data were collected on the discrepancies between men’s actual muscularity and perceptions of their off-line male and female peers’ male ideal, and perceptions of the male ideal from men and women on social networking sites (SNSs). A total of 277 adult men ( Mage = 36.55; SD = 11.34) completed a survey online. Actual–ideal discrepancies were present for all four comparison ideals. Overall body satisfaction was significantly linked to the close female friend ideal discrepancy, whereas muscularity satisfaction was connected to all four comparison ideals. Body fat satisfaction was not impacted by any of the discrepancies. The most significant predictor of muscularity satisfaction was the close female friends’ ideal discrepancy. Implications suggest the continued use of self-discrepancy theory in new contexts, and continued importance of off-line relationships, despite SNS use.

Dynamic model of an air spring and integration into a vehicle dynamics model

2008 ◽  
Vol 222 (10) ◽  
pp. 1813-1825 ◽  
Author(s):  
F Chang ◽  
Z-H Lu
Keyword(s):  
Dynamic Model ◽  
Vehicle Dynamics ◽  
Simulation Method ◽  
Heat Transfer Process ◽  
Spring Model ◽  
Dynamics Model ◽  
Air Spring ◽  
Full Vehicle ◽  
Body Dynamics ◽  
Multi Body

It is worthwhile to design a more accurate dynamic model for air springs, to investigate the dynamic behaviour of an air spring suspension, and to analyse and guide the design of vehicles with air spring suspensions. In this study, a dynamic model of air spring was established, considering the heat transfer process of the air springs. Two different types of air spring were tested, and the experimental results verified the effectiveness of the air spring model compared with the traditional model. The key factors affecting the computation accuracy were studied and checked by comparing the results of the experiments and simulations. The new dynamic model of the air spring was integrated into the full-vehicle multi-body dynamics model, in order to investigate the air suspension behaviour and vehicle dynamics characteristics. The co-simulation method using ADAMS and MATLAB/Simulink was applied to integration of the air spring model with the full-vehicle multi-body dynamics model.

scholarly journals COVID-19 attack ratio among children critically depends on the time to removal and activity levels

2021 ◽  
Author(s):  
Jianhong Wu ◽  
Nicola Luigi Bragazzi ◽  
Francesca Scarabel ◽  
Zachary McCarthy ◽  
Jummy David ◽  
...  
Keyword(s):  
Total Population ◽  
Vaccine Coverage ◽  
Herd Immunity ◽  
Activity Levels ◽  
Rapid Testing ◽  
Dynamics Model ◽  
Canadian Population ◽  
Social Mixing ◽  
Number Of Individuals ◽  
The Relationship

The attack ratio in a subpopulation is defined as the total number of infections over the total number of individuals in this subpopulation. Using a methodology based on modified age-stratified transmission dynamics model, we estimated the attack ratio of COVID-19 among children (individuals 0-11 years) in Ontario, Canada when a large proportion of individuals eligible for vaccination (age 12 and above) are vaccinated to achieve herd immunity among this subpopulation, or the effective herd immunity with additional physical distancing measures (hence effective herd immunity). We describe the relationship between this attack ratio among children, the time to remove infected individuals from the transmission chain and the children-to-children daily contact rate, while considering the increased transmissibility of virus variants (using the Delta variant as an example). We further illustrate the generality and applicability of the methodology established by performing an analysis of the attack ratio of COVID-19 among children in the Canadian population. The clinical attack ratio, the number of symptomatic infections over the total population can be informed from the attack ratio, and both can be reduced substantially via a combination of higher vaccine coverage in the vaccine eligible population, reduced social mixing among children, and rapid testing and isolation.

scholarly journals PECULIARITIES OF CORRECTING THE FIGURE AMONG WOMEN OF THE FIRST MATURE AGE PERIOD BY MEANS OF SHAPING TECHNIQUES IN ACCORDANCE WITH BODY TYPES

2021 ◽  
Vol 5 (1) ◽  
pp. 30-42
Author(s):  
Olga Kozhanova ◽  
Sergii Pitenko ◽  
Natalia Gavrilova ◽  
Evgeniya Tsуkozа ◽  
Hanna Hudym ◽  
...  
Keyword(s):  
Physical Condition ◽  
Body Shape ◽  
Current Practice ◽  
Control Group ◽  
Body Type ◽  
Adult Age ◽  
New Approaches ◽  
Sports Club ◽  
Experimental Group ◽  
Selection Of

Introduction. Currently, due to environmental and social problems, nervous strain, muscle inactivity, more and more people are starting to engage in health fitness in the hope of improving health, improving physical condition, learning how to deal with stress and lose weight. Nowadays, compared to other types of fitness, shaping classes have become more and more popular as an effective way to lose weight and body shape. Although shaping was originally developed as a system of individual classes, the current practice of group classes requires the search for new approaches in planning shaping programs: there is no research on the selection of exercises, volume and intensity of classes based on individual physiques of those involved. Aim: to increase the effectiveness of classes in order to correct the figure of women 21-35 years old through the use of shaping programs, taking into account their body types. Material and methods. The study involved 30 women aged 21 - 35 years, divided into control and experimental groups, in which 15 people each were divided by somatotype. The pedagogical experiment was conducted on the basis of the sports club "Fitness Box" in Kyiv. Results. It was found that as a result of the application of the developed shaping program in the women of the experimental group there was a decrease in the fat layer in endomorphs by 13.2%, and in the control group of endomorphs by 7.2% (p < 0,05). Changes in the fat layer in the control and experimental groups are supplemented by changes in girth: chest, shoulder, abdomen, thighs, buttocks, the dynamics of which proves the effectiveness of our program compared to traditional. Conclusions. The application of the developed shaping program allows to solve the problem of improving the efficiency of shaping in order to correct the figure taking into account endomorphic body type of women first adult age.

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