scholarly journals Investigating the running abilities ofTyrannosaurus rexusing stress-constrained multibody dynamic analysis

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3420 ◽  
Author(s):  
William I. Sellers ◽  
Stuart B. Pond ◽  
Charlotte A. Brassey ◽  
Philip L. Manning ◽  
Karl T. Bates
Keyword(s):  
Soft Tissue ◽  
Dynamic Analysis ◽  
Stress Analysis ◽  
Feeding Behaviour ◽  
High Speed ◽  
New Approach ◽  
Wide Range ◽  
Multibody Dynamic ◽  
High Level ◽  
Walking Speeds

The running ability ofTyrannosaurus rexhas been intensively studied due to its relevance to interpretations of feeding behaviour and the biomechanics of scaling in giant predatory dinosaurs. Different studies using differing methodologies have produced a very wide range of top speed estimates and there is therefore a need to develop techniques that can improve these predictions. Here we present a new approach that combines two separate biomechanical techniques (multibody dynamic analysis and skeletal stress analysis) to demonstrate that true running gaits would probably lead to unacceptably high skeletal loads inT. rex. Combining these two approaches reduces the high-level of uncertainty in previous predictions associated with unknown soft tissue parameters in dinosaurs, and demonstrates that the relatively long limb segments ofT. rex—long argued to indicate competent running ability—would actually have mechanically limited this species to walking gaits. Being limited to walking speeds contradicts arguments of high-speed pursuit predation for the largest bipedal dinosaurs likeT. rex, and demonstrates the power of multiphysics approaches for locomotor reconstructions of extinct animals.

Effects of Body Mass Index on Step Count Accuracy of Physical Activity Monitors

2012 ◽  
Vol 9 (4) ◽  
pp. 594-600 ◽  
Author(s):  
Yuri Feito ◽  
David R. Bassett ◽  
Dixie L. Thompson ◽  
Brian M. Tyo
Keyword(s):  
Physical Activity ◽  
Body Mass Index ◽  
Body Mass ◽  
Step Count ◽  
Activity Monitors ◽  
Wide Range ◽  
Step Counting ◽  
Physical Activity Monitors ◽  
High Level ◽  
Walking Speeds

Background:Activity monitors are widely used in research, and are currently being used to study physical activity (PA) trends in the US and Canada. The purpose of this study was to determine if body mass index (BMI) affects the step count accuracy of commonly used accelerometer-based activity monitors during treadmill walking.Methods:Participants were classified into BMI categories and instructed to walk on a treadmill at 3 different speeds (40, 67, and 94 m·min−1) while wearing 4 accelerometer-based activity monitors (ActiGraph GT1M, ActiCal, NL-2000, and StepWatch).Results:There was no significant main effect of BMI on pedometer accuracy. At the slowest speed, all waist-mounted devices significantly underestimated actual steps (P < .001), with the NL-2000 recording the greatest percentage (72%). At the intermediate speed, the ActiGraph was the least accurate, recording only 80% of actual steps. At the fastest speed, all of the activity monitors demonstrated a high level of accuracy.Conclusion:Our data suggest that BMI does not greatly affect the step-counting accuracy of accelerometer-based activity monitors. However, the accuracy of the ActiGraph, ActiCal, and NL-2000 decreases at slower speeds. The ankle-mounted StepWatch was the most accurate device across a wide range of walking speeds.

scholarly journals Race Walking Ground Reaction Forces at Increasing Speeds: A Comparison with Walking and Running

Symmetry ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 873
Author(s):  
Gaspare Pavei ◽  
Dario Cazzola ◽  
Antonio La Torre ◽  
Alberto E. Minetti
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
The Body ◽  
Ground Reaction Forces ◽  
Centre Of Mass ◽  
Walking Gait ◽  
Wide Range ◽  
Reaction Forces ◽  
Race Walking ◽  
Walking Speeds

Race walking has been theoretically described as a walking gait in which no flight time is allowed and high travelling speed, comparable to running (3.6–4.2 m s−1), is achieved. The aim of this study was to mechanically understand such a “hybrid gait” by analysing the ground reaction forces (GRFs) generated in a wide range of race walking speeds, while comparing them to running and walking. Fifteen athletes race-walked on an instrumented walkway (4 m) and three-dimensional GRFs were recorded at 1000 Hz. Subjects were asked to performed three self-selected speeds corresponding to a low, medium and high speed. Peak forces increased with speeds and medio-lateral and braking peaks were higher than in walking and running, whereas the vertical peaks were higher than walking but lower than running. Vertical GRF traces showed two characteristic patterns: one resembling the “M-shape” of walking and the second characterised by a first peak and a subsequent plateau. These different patterns were not related to the athletes’ performance level. The analysis of the body centre of mass trajectory, which reaches its vertical minimum at mid-stance, showed that race walking should be considered a bouncing gait regardless of the presence or absence of a flight phase.

A Driving-Gear Dynamic Analysis

2018 ◽  
Vol 931 ◽  
pp. 422-427
Author(s):  
Yevgeniy M. Kudryavtsev
Keyword(s):  
Mathematical Model ◽  
Differential Equations ◽  
Dynamic Analysis ◽  
Second Order ◽  
New Approach ◽  
First Order ◽  
Gear Design ◽  
Third Stage ◽  
Mathcad Software ◽  
High Level

A new approach of mechanical driving-gear dynamic analysis, which includes several modelling stages is observed in the article. On the first stage driving-gear is represented in the form of consistently connected rotation bodies. The driving-gear is represented in a graphic kind by means of the marked graph. On the second stage mathematical model of driving-gear performance with using of mnemonic rule is created. Mathematical model of mechanical driving-gear is a system of second-order regular differential equations (RDEs). The system of second-order regular differential equations is transformed into a system of first-order regular differential equations. There is a standard method for writing a higher-order RDE as a system of the first-order RDEs. On the third stage computer model of driving-gear performance using system Mathcad is created and initial data is defined. On the fourth stage the mechanical driving-gear modelling is performed and calculation data in numerical and graphical forms is obtained. This approach provides high level of the driving-gear dynamic analysis, including the received results presentation, which is especially important on the earliest stages of mechanical driving-gear design. The proposed procedure of mechanical driving-gear dynamic analysis using Mathcad software significantly decreases time and working costs on execution of such computations and helps to execute investigations related with changing of driving-gear elements parameters efficiently.

scholarly journals Innovation Resilience: A New Approach for Managing Uncertainties Concerned with Sustainable Innovation

2018 ◽  
Vol 10 (10) ◽  
pp. 3641 ◽  
Author(s):  
Wen-Dong Lv ◽  
Dan Tian ◽  
Yuan Wei ◽  
Rui-Xue Xi
Keyword(s):  
Innovation Management ◽  
Empirical Studies ◽  
Two Dimensions ◽  
New Approach ◽  
Sustainable Innovation ◽  
Wide Range ◽  
Multiple Case ◽  
Multiple Case Studies ◽  
Market Driven ◽  
High Level

Sustainable innovation is more complex than conventional, market-driven innovation, because companies have to consider a wide range of uncertainties concerned with the environment, society, and economics. This literature review shows that resilience is the prevailing way of thinking in the area of sustainability studies, and the main contribution of resilience to sustainability is how to deal with uncertainties. However, there seems to be a scarcity in the current literature on the conceptualization of resilience in the context of innovation. From the duality view, this paper proposes a new concept of innovation resilience based on two dimensions, stability and adaptability, which contribute to maintaining a high level of innovation efficiency, while at the same time adapting to change. The proposed innovation resilience concept attempts to provide an integration of divergent research streams—innovation management, organizational resilience, and sustainability management theory. We develop a conceptual framework that consists of a set of indicators involving the two dimensions by using multiple case studies, upon which future empirical studies can be based.

scholarly journals REFLEKSYJNOŚĆ W ŚWIETLE TEKSTÓW EUROPEJSKIEGO SYSTEMU OPISU KSZTAŁCENIA JĘZYKOWEGO

Neofilolog ◽  
2019 ◽  
Vol 2 (42/2) ◽  
pp. 143-154
Author(s):  
Iwona Janowska
Keyword(s):  
Learning Objectives ◽  
New Approach ◽  
New Era ◽  
Wide Range ◽  
The Status ◽  
The Common ◽  
A Priority ◽  
High Level

The Common European Framework of Reference for Languages is a document characterized by a high level of generality, addressed to a wide range of readers. The conceptual paradigm included in the document could constitute the basis for a new trend in language didactics; however, a lot of further work and research should be carried out for the new approach to achieve the status of independent and efficient methodology. The first prerequisite for introducing necessary modifications is a reflexive approach to the recommendations of CEFR, especially those which are methodological in character. The lack of any rules or procedures showing how to facilitate the achievement of learning objectives is the most frequent objection made against the CEFR. The focus on what has to be taught should go along with how to teach and why. Reflexivity which occupies a marginal position in the CEFR has to become a priority for its users if the methodology outlined there is to constitute the new era in language didactics.

scholarly journals Calculating correct compilers

2015 ◽  
Vol 25 ◽  
Author(s):  
PATRICK BAHR ◽  
GRAHAM HUTTON
Keyword(s):  
Proof Assistant ◽  
General Technique ◽  
New Approach ◽  
Equational Reasoning ◽  
Systematic Calculation ◽  
The Coq Proof Assistant ◽  
Wide Range ◽  
Calculation Process ◽  
Coq Proof Assistant ◽  
High Level

AbstractIn this article, we present a new approach to the problem of calculating compilers. In particular, we develop a simple but general technique that allows us to derive correct compilers from high-level semantics by systematic calculation, with all details of the implementation of the compilers falling naturally out of the calculation process. Our approach is based upon the use of standard equational reasoning techniques, and has been applied to calculate compilers for a wide range of language features and their combination, including arithmetic expressions, exceptions, state, various forms of lambda calculi, bounded and unbounded loops, non-determinism and interrupts. All the calculations in the article have been formalised using the Coq proof assistant, which serves as a convenient interactive tool for developing and verifying the calculations.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

Factors Affecting Molecular Self-Assembly and Its Mechanism

2012 ◽  
Vol 9 (1) ◽  
pp. 43 ◽  
Author(s):  
Hueyling Tan
Keyword(s):  
Self Assembly ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Molecular Structures ◽  
Polymer Science ◽  
New Approach ◽  
Factors Affecting ◽  
Dna Structures ◽  
Self Assembling ◽  
Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

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