On the use of jerk and snap in condition monitoring of machinery – review and case studies

2021 ◽  
Vol 63 (8) ◽  
pp. 457-464
Author(s):  
S Lahdelma
Keyword(s):  
Condition Monitoring ◽  
Large Scale ◽  
Early Stage ◽  
Time Derivative ◽  
Additional Insight ◽  
Rolling Bearings ◽  
Monitoring Applications ◽  
Derivatives Of ◽  
Insight Into ◽  
Peak Value

The time derivatives of acceleration offer a great advantage in detecting impact-causing faults at an early stage in condition monitoring applications. Defective rolling bearings and gears are common faults that cause impacts. This article is based on extensive real-world measurements, through which large-scale machines have been studied. Numerous laboratory experiments provide additional insight into the matter. A practical solution for detecting faults with as few features as possible is to measure the root mean square (RMS) velocity according to the standards in the frequency range from 10 Hz to 1000 Hz and the peak value of the second time derivative of acceleration, ie snap. Measuring snap produces good results even when the upper cut-off frequency is as low as 2 kHz or slightly higher. This is valuable information when planning the mounting of accelerometers.

Electroencephalography

2016 ◽  
Author(s):  
Michael B. Gaetz ◽  
Kelly J. Jantzen
Keyword(s):  
Cognitive Deficits ◽  
Large Scale ◽  
Pyramidal Neurons ◽  
Neurological Dysfunction ◽  
Additional Insight ◽  
Physiological Basis ◽  
Sport Concussion ◽  
Neurochemical Changes ◽  
Insight Into ◽  
Behavior And Cognition

Axonal injury is currently considered to be the structural substrate behind most concussion-related neurological dysfunction. Because the principal generators of EEG fields are graded excitatory and inhibitory synaptic potentials of pyramidal neurons, the EEG is well suited for characterizing large-scale functional disruptions associated with concussion induced metabolic and neurochemical changes, and for connecting those disruptions to deficits in behavior and cognition. This essay provides an overview of the use of EEG and newly developed analytical procedures for the measurement of functional impairment related to sport concussion. Elevations in delta and theta activity can be expected in a percentage of athletes and change in asymmetry and coherence may also be present. Newer techniques are likely to be of critical importance for understanding the anatomical and physiological basis of cognitive deficits and may provide additional insight into susceptibility to future injury. Computational modeling may advance our understanding of concussion.

scholarly journals KEAP1 Cancer Mutants: A Large-Scale Molecular Dynamics Study of Protein Stability

2021 ◽  
Vol 22 (10) ◽  
pp. 5408
Author(s):  
Carter Wilson ◽  
Megan Chang ◽  
Mikko Karttunen ◽  
Wing-Yiu Choy
Keyword(s):  
Molecular Dynamics ◽  
Large Scale ◽  
Md Simulations ◽  
Covalent Modification ◽  
Additional Insight ◽  
New Class ◽  
Kelch Domain ◽  
Cancer Mutations ◽  
Mutagenic Effects ◽  
Insight Into

We have performed 280 μs of unbiased molecular dynamics (MD) simulations to investigate the effects of 12 different cancer mutations on Kelch-like ECH-associated protein 1 (KEAP1) (G333C, G350S, G364C, G379D, R413L, R415G, A427V, G430C, R470C, R470H, R470S and G476R), one of the frequently mutated proteins in lung cancer. The aim was to provide structural insight into the effects of these mutants, including a new class of ANCHOR (additionally NRF2-complexed hypomorph) mutant variants. Our work provides additional insight into the structural dynamics of mutants that could not be analyzed experimentally, painting a more complete picture of their mutagenic effects. Notably, blade-wise analysis of the Kelch domain points to stability as a possible target of cancer in KEAP1. Interestingly, structural analysis of the R470C ANCHOR mutant, the most prevalent missense mutation in KEAP1, revealed no significant change in structural stability or NRF2 binding site dynamics, possibly indicating an covalent modification as this mutant’s mode of action.

scholarly journals Adapting for Scalability: Automating the Video Assessment of Instructional Learning

2017 ◽  
Vol 21 (1) ◽  
Author(s):  
Amy M Roberts ◽  
Jennifer LoCasale-Crouch ◽  
Bridget K Hamre ◽  
Jordan M Buckrop
Keyword(s):  
Scoring System ◽  
Large Scale ◽  
Online Courses ◽  
Current Paper ◽  
Automated Scoring ◽  
Additional Insight ◽  
Knowledge And Skills ◽  
Video Assessment ◽  
Reliable Assessment ◽  
Insight Into

Although scalable programs, such as online courses, have the potential to reach broad audiences, they may pose challenges to evaluating learners’ knowledge and skills. Automated scoring offers a possible solution. In the current paper, we describe the process of creating and testing an automated means of scoring a validated measure of teachers’ observational skills, known as the Video Assessment of Instructional Learning (VAIL). Findings show that automated VAIL scores were consistently correlated with scores assigned by the hand scoring system. In addition, the automated VAIL replicated intervention effects found in the hand scoring system. The automated scoring technique appears to offer an efficient and reliable assessment. This study may offer additional insight into how to utilize similar techniques in other large-scale programs and interventions.

scholarly journals Identification of Chromatin Accessibility During The Early Stage of Pig SCNT Embryo Reprogramming by ATAC-Seq

2020 ◽  
Author(s):  
Xue Zhang ◽  
Juan Li ◽  
Ruixin Tao ◽  
Aiwen Jiang ◽  
Changyin Zhou ◽  
...  
Keyword(s):  
Histone Modification ◽  
Large Scale ◽  
Transcriptional Activity ◽  
Early Stage ◽  
Enrichment Analysis ◽  
Chromatin Accessibility ◽  
Nuclear Transplantation ◽  
Dynamic Changes ◽  
Accessible Chromatin ◽  
Insight Into

Abstract Background: Somatic cell nuclear transplantation (SCNT) can transform highly differentiated donor nuclei into pluripotent nuclei through the large-scale reprogramming of chromatin. The reprogramming of chromatin has been documented to take place in the first few hours after SCNT embryo activation. Thus, studies that characterize dynamic changes in chromatin during the first few hours after embryo activation could provide insight into the mechanism and significance of genome-wide reprogramming. However, few studies have examined the epigenetic remodeling of reconstructed embryos during the early stage of reprogramming.Results: We conducted ATAC-seq on 50 porcine SCNT-HMC embryos and 50 parthenogenetic activation (PA) embryos 10 h after activation. Along with pig embryonic fibroblast (PEF) ATAC-seq data, we found low levels of chromatin accessibility and gene transcription in SCNT and PA embryos. Moreover, PEF genes and the X chromosome became inaccessible during embryo reprogramming. GO enrichment analysis revealed that the molecular functions related to accessible chromatin in embryos primarily included transcriptional regulatory activity and SMAD binding. The differentially accessible chromatin sites between SCNT and PEF were primarily related to transcriptional activity and histone modification.Conclusions: Despite the tight chromatin structure during the early stage of embryo reprogramming, some accessible chromatin sites, which were primarily distributed in the intergenic region, were still detected. Dynamic changes in chromatin accessibility during reprogramming were primarily related to transcriptional activity and histone modification. Generally, this study provided new insight into the dynamics and importance of chromatin accessibility during the early stages of embryo reprogramming.

Predictive Numerical Modeling of Artificial Tracers Migration in the Large-Scale Heating and Hydration Experiments of the FEBEX Project

1997 ◽  
Vol 506 ◽  
Author(s):  
J. Samper ◽  
J. Delgado ◽  
J. Molinero ◽  
R. Juncosa
Keyword(s):  
Numerical Modeling ◽  
Large Scale ◽  
The Novel ◽  
Additional Insight ◽  
Bentonite Buffer ◽  
Waste Repository ◽  
Engineered Barrier ◽  
High Level ◽  
Insight Into ◽  
Artificial Tracers

ABSTRACTFEBEX (Full-scale Engineered Barrier EXperiment) is a demonstration and research project dealing with the bentonite engineered barrier designed for sealing and containment of waste in a high level radioactive waste repository. In the FEBEX experiment the bentonite barrier will be subject to heating and hydration during at least three years. One of the novel aspects of FEBEX is the use of artificial tracers, which are intended to provide additional insight into the hydrodynamic and geochemical behavior of the bentonite buffer. Here the results of the numerical prediction of tracers migration are presented. Numerical modeling of the experiments has allowed the identification of the most relevant parameters and will be useful for the design of post-morten analyses.

scholarly journals Mutations affecting development of the notochord in zebrafish

Development ◽  
1996 ◽  
Vol 123 (1) ◽  
pp. 117-128 ◽  
Author(s):  
D.L. Stemple ◽  
L. Solnica-Krezel ◽  
F. Zwartkruis ◽  
S.C. Neuhauss ◽  
A.F. Schier ◽  
...  
Keyword(s):  
Large Scale ◽  
Normal Development ◽  
Paraxial Mesoderm ◽  
Skeletal Element ◽  
Additional Insight ◽  
Genetic Pathway ◽  
Complementation Groups ◽  
Vertebrate Embryos ◽  
Insight Into

The notochord is critical for the normal development of vertebrate embryos. It serves both as the major skeletal element of the embryo and as a signaling source for the establishment of pattern within the neurectoderm, the paraxial mesoderm and other tissues. In a large-scale systematic screen of mutations affecting embryogenesis in zebrafish we identified 65 mutations that fall into 29 complementation groups, each leading to a defect in the formation and/or maintenance of the notochord. These mutations produce phenotypic abnormalities at numerous stages of notochord development, thereby establishing a phenotypic pathway, which in turn suggests a genetic pathway for the development of the notochord. Perturbations within adjacent tissues in mutant embryos further indicate the importance of notochord-derived signals for patterning within the embryo and suggest that these mutations will yield additional insight into the cues that regulate these patterning processes.

FOUNDATIONS OF FRACTIONAL DYNAMICS

Fractals ◽  
1995 ◽  
Vol 03 (03) ◽  
pp. 549-556 ◽  
Author(s):  
R. HILFER
Keyword(s):  
Measure Zero ◽  
Time Derivative ◽  
Time Limit ◽  
Fractional Dynamics ◽  
Equilibrium Concept ◽  
Time Step ◽  
Time Flow ◽  
Generalized Equilibrium ◽  
Derivatives Of ◽  
Insight Into

Time flow in dynamical systems is reconsidered in the ultralong time limit. The ultralong time limit is a limit in which a discretized time flow is iterated infinitely often and the discretization time step is infinite. The new limit is used to study induced flows in ergodic theory, in particular for subsets of measure zero. Induced flows on subsets of measure zero require an infinite renormalization of time in the ultralong time limit. It is found that induced flows are given generically by stable convolution semigroups and not by the conventional translation groups. This could give new insight into the origin of macroscopic irreversibility. Moreover, the induced semigroups are generated by fractional time derivatives of orders less than unity, and not by a first order time derivative. Invariance under the induced semiflows therefore leads to a new form of stationarity, called fractional stationarity. Fractionally stationary states are dissipative. Fractional stationarity also provides the dynamical foundation for a previously proposed generalized equilibrium concept.

Scalable prognostic models for large-scale condition monitoring applications

2017 ◽  
Vol 49 (7) ◽  
pp. 698-710 ◽  
Author(s):  
Xiaolei Fang ◽  
Nagi Z. Gebraeel ◽  
Kamran Paynabar
Keyword(s):  
Condition Monitoring ◽  
Large Scale ◽  
Prognostic Models ◽  
Monitoring Applications

Classification of Infant Vocalizations by Untrained Listeners

2019 ◽  
Vol 62 (9) ◽  
pp. 3265-3275
Author(s):  
Heather L. Ramsdell-Hudock ◽  
Anne S. Warlaumont ◽  
Lindsey E. Foss ◽  
Candice Perry
Keyword(s):  
Formal Education ◽  
Additional Insight ◽  
Listener Responses ◽  
Infant Vocalization ◽  
Early Infant ◽  
Infant Vocalizations ◽  
Audio Recordings ◽  
Speech And Language Development ◽  
Insight Into

Purpose To better enable communication among researchers, clinicians, and caregivers, we aimed to assess how untrained listeners classify early infant vocalization types in comparison to terms currently used by researchers and clinicians. Method Listeners were caregivers with no prior formal education in speech and language development. A 1st group of listeners reported on clinician/researcher-classified vowel, squeal, growl, raspberry, whisper, laugh, and cry vocalizations obtained from archived video/audio recordings of 10 infants from 4 through 12 months of age. A list of commonly used terms was generated based on listener responses and the standard research terminology. A 2nd group of listeners was presented with the same vocalizations and asked to select terms from the list that they thought best described the sounds. Results Classifications of the vocalizations by listeners largely overlapped with published categorical descriptors and yielded additional insight into alternate terms commonly used. The biggest discrepancies were found for the vowel category. Conclusion Prior research has shown that caregivers are accurate in identifying canonical babbling, a major prelinguistic vocalization milestone occurring at about 6–7 months of age. This indicates that caregivers are also well attuned to even earlier emerging vocalization types. This supports the value of continuing basic and clinical research on the vocal types infants produce in the 1st months of life and on their potential diagnostic utility, and may also help improve communication between speech-language pathologists and families.

Konkurrenz zwischen Stieleiche und Buche auf Lothar-Sturmflächen | Competition between pedunculate oak and European beech on Lothar windthrow areas

2009 ◽  
Vol 160 (5) ◽  
pp. 114-123 ◽  
Author(s):  
Daniel Otto ◽  
Sven Wagner ◽  
Peter Brang
Keyword(s):  
Large Scale ◽  
Early Stage ◽  
Tree Height ◽  
European Beech ◽  
Threshold Value ◽  
Test Methods ◽  
Permanent Plots ◽  
Pedunculate Oak ◽  
Competitive Pressure ◽  
Competition Index

The competitive pressure of naturally regenerated European beech (Fagus sylvatica) saplings on planted pedunculate oak (Quercus robur) was investigated on two 1.8 ha permanent plots near Habsburg and Murten (Switzerland). The plots were established with the aim to test methods of artificial oak regeneration after large-scale windthrow. On both plots, 80 oaks exposed to varying levels of competitive pressure from at most 10 neighbouring beech trees were selected. The height of each oak as well as stem and branch diameters were measured. The competitive pressure was assessed using Schütz's competition index, which is based on relative tree height, crown overlap and distance from competing neighbours. Oak trees growing without or with only slight competition from beech were equally tall, while oaks exposed to moderate to strong competition were smaller. A threshold value for the competition index was found above which oak height decreased strongly. The stem and branch diameters of the oaks started to decrease even if the competition from beech was slight, and decreased much further with more competition. The oak stems started to become more slender even with only slight competition from beech. On the moderately acid beech sites studied here, beech grow taller faster than oak. Thus where beech is competing with oak and the aim is to maintain the oak, competitive pressure on the oak must be reduced at an early stage. The degree of the intervention should, however, take the individual competitive interaction into account, with more intervention if the competition is strong.

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