Passive Balancing of Rotor Systems Using Pendulum Balancers

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Roland Horvath ◽  
George T. Flowers ◽  
Jerry Fausz
Keyword(s):  
Simulation Model ◽  
Dynamic Characteristics ◽  
Recent Literature ◽  
Experimental Studies ◽  
Simulation Studies ◽  
Additional Insight ◽  
Rotor Systems ◽  
Rolling Balls ◽  
Insight Into

Passive balancing techniques have received a great deal of attention in recent literature, with much of this work focused on ball balancer systems. However, for certain applications, balancing systems that use pendulums rather than rolling balls may offer distinctly improved balancing precision. This investigation seeks to provide additional insight into the performance and expected behavior of such systems. A simulation model is developed for a pendulum balancer system with isotropic supports and analyzed in detail. The influence of shaft location and friction on balancing effectiveness is considered and evaluated. In this regard, the dynamic characteristics of a pendulum balancer system are analyzed and compared to a similar ball balancer system. The conclusions and observations from the analysis and simulation studies are demonstrated and tested in a series of experimental studies.

EXPERIMENTAL STUDIES MULTI-SUPPORTED SHAFTING

2020 ◽  
Vol 5 ◽  
pp. 80-84
Author(s):  
M.E. BONDARENKO ◽  
R.N. POLYAKOV ◽  
I.V. RODICHEVA ◽  
M.A. GRIADYNOVA
Keyword(s):  
Dynamic Characteristics ◽  
Experimental Studies ◽  
Measuring System ◽  
Experimental Setup ◽  
Experimental Equipment ◽  
Software Complex ◽  
Rotor Systems ◽  
Information Measuring System ◽  
Generating Equipment ◽  
Power Generating Equipment

The article presents an analysis of various types of experimental equipment that simulates the operation of flexible shaft lines of power generating machines and units. Based on the analysis results, an experimental setup is presented for investigating the dynamic characteristics of multi-support rotor systems. An information-measuring system is proposed to ensure the operation of a dynamic stand based on a hardware-software complex of the "National Instruments" company. The results of experimental studies of multi-support rotor systems used in power generating equipment are presented.

scholarly journals Synthetic Reproduction and Augmentation of COVID-19 Case Reporting Data by Agent-Based Simulation

2020 ◽  
Author(s):  
Nikolas Popper ◽  
Melanie Zechmeister ◽  
Dominik Brunmeir ◽  
Claire Rippinger ◽  
Nadine Weibrecht ◽  
...  
Keyword(s):  
Simulation Model ◽  
Historical Data ◽  
Synthetic Data ◽  
Agent Based Simulation ◽  
Additional Insight ◽  
Data Set ◽  
Agent Based ◽  
Patient Pathways ◽  
Insight Into ◽  
Reporting Data

AbstractWe generate synthetic data documenting COVID-19 cases in Austria by the means of an agent-based simulation model. The model simulates the transmission of the SARS-CoV-2 virus in a statistical replica of the population and reproduces typical patient pathways on an individual basis while simultaneously integrating historical data on the implementation and expiration of population-wide countermeasures. The resulting data semantically and statistically aligns with an official epidemiological case reporting data set and provides an easily accessible, consistent and augmented alternative. Our synthetic data set provides additional insight into the spread of the epidemic by synthesizing information that cannot be recorded in reality.

Atomistic Studies of Intrinsic Crack-Tip Plasticity

MRS Bulletin ◽  
2000 ◽  
Vol 25 (5) ◽  
pp. 35-38 ◽  
Author(s):  
Diana Farkas
Keyword(s):  
Plastic Deformation ◽  
Energy Dissipation ◽  
Atomistic Simulation ◽  
Experimental Studies ◽  
Crack Tip ◽  
Atomic Level ◽  
Simulation Studies ◽  
Precise Understanding ◽  
Crack Tip Plasticity ◽  
Insight Into

One of the most interesting unsolved problems in fracture mechanics is the precise understanding of the energy-dissipation mechanisms that occur as a crack advances. In most cases, this energy-release rate is many times the surface energy created. One of the main reasons for this difference is the fact that plastic deformation can occur in the crack-tip region as dislocations nucleate and are emitted from the crack tip. Experimental studies provide little insight into the precise mechanisms for this process because they cannot reach the atomistic scale. For example, a crack that may seem experimentally sharp, and therefore indicative of brittle fracture, may not be sharp at the atomic level. Continuum mechanics has a similar limitation, since the assumptions of elasticity theory usually break down in the crack-tip region. Atomistic simulation studies provide researchers an opportunity to obtain precise atomic configurations in the crack-tip region under various loading conditions and to observe the basic energy-dissipation mechanisms.

scholarly journals Modelling the flight dynamics of aerial target imitator

2018 ◽  
Vol 48 (1) ◽  
pp. 119-147
Author(s):  
Roman Kamiński ◽  
Marian Tybura ◽  
Zygmunt Winczura ◽  
Andrzej Żyluk
Keyword(s):  
Physical Model ◽  
Dynamic Characteristics ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Flight Dynamics ◽  
Theoretical Studies ◽  
Simulation Studies ◽  
Technical Data ◽  
Basic Parameters ◽  
Experimental And Theoretical Studies

Abstract This article is concerned with the issue related to studying the dynamic properties of the aerial target imitator. Applying the modelling principles, the structure and technical data of aerial target imitator were described and utilising the PRODAS software a physical model of the aerial imitator was developed based on the conducted simulation studies. Mass, aerodynamic and basic parameters of flight path were determined. Then, experimental studies of basic dynamic characteristics were discussed. The comparison of results obtained from experimental and theoretical studies proves the correctness of the developed model.

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.

Diversity, Rationality, and the Division of Cognitive Labor

2017 ◽  
Author(s):  
Ryan Muldoon
Keyword(s):  
Social Structure ◽  
Division Of Labor ◽  
Additional Insight ◽  
Division Of Cognitive Labor ◽  
Social Structure Of Science ◽  
The Social ◽  
Insight Into

Existing models of the division of cognitive labor in science assume that scientists have a particular problem they want to solve and can choose between different approaches to solving the problem. In this essay I invert the approach, supposing that scientists have fixed skills and seek problems to solve. This allows for a better explanation of increasing rates of cooperation in science, as well as flows of scientists between fields of inquiry. By increasing the realism of the model, we gain additional insight into the social structure of science and gain the ability to ask new questions about the optimal division of labor.

scholarly journals Using syndromic measures of mortality to capture the dynamics of COVID-19 in Java, Indonesia, in the context of vaccination rollout

BMC Medicine ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Bimandra A. Djaafara ◽  
Charles Whittaker ◽  
Oliver J. Watson ◽  
Robert Verity ◽  
Nicholas F. Brazeau ◽  
...  
Keyword(s):  
Rural Areas ◽  
Vaccination Campaign ◽  
Control Measures ◽  
Additional Insight ◽  
Short Term ◽  
If Current ◽  
Vaccine Impact ◽  
Potential Impact ◽  
The Impact ◽  
Insight Into

Abstract Background As in many countries, quantifying COVID-19 spread in Indonesia remains challenging due to testing limitations. In Java, non-pharmaceutical interventions (NPIs) were implemented throughout 2020. However, as a vaccination campaign launches, cases and deaths are rising across the island. Methods We used modelling to explore the extent to which data on burials in Jakarta using strict COVID-19 protocols (C19P) provide additional insight into the transmissibility of the disease, epidemic trajectory, and the impact of NPIs. We assess how implementation of NPIs in early 2021 will shape the epidemic during the period of likely vaccine rollout. Results C19P burial data in Jakarta suggest a death toll approximately 3.3 times higher than reported. Transmission estimates using these data suggest earlier, larger, and more sustained impact of NPIs. Measures to reduce sub-national spread, particularly during Ramadan, substantially mitigated spread to more vulnerable rural areas. Given current trajectory, daily cases and deaths are likely to increase in most regions as the vaccine is rolled out. Transmission may peak in early 2021 in Jakarta if current levels of control are maintained. However, relaxation of control measures is likely to lead to a subsequent resurgence in the absence of an effective vaccination campaign. Conclusions Syndromic measures of mortality provide a more complete picture of COVID-19 severity upon which to base decision-making. The high potential impact of the vaccine in Java is attributable to reductions in transmission to date and dependent on these being maintained. Increases in control in the relatively short-term will likely yield large, synergistic increases in vaccine impact.

scholarly journals Shedding light on the nature of the catalytically active species in photocatalytic reactions using Bi2O3 semiconductor

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Paola Riente ◽  
Mauro Fianchini ◽  
Patricia Llanes ◽  
Miquel A. Pericàs ◽  
Timothy Noël
Keyword(s):  
Experimental Studies ◽  
Heterogeneous Photocatalysis ◽  
Active Species ◽  
Organic Transformations ◽  
Alkyl Bromides ◽  
Catalytically Active ◽  
Visible Light Driven ◽  
Photocatalytic Reactions ◽  
Insight Into ◽  
Photocatalytic Processes

AbstractThe importance of discovering the true catalytically active species involved in photocatalytic systems allows for a better and more general understanding of photocatalytic processes, which eventually may help to improve their efficiency. Bi2O3 has been used as a heterogeneous photocatalyst and is able to catalyze several synthetically important visible-light-driven organic transformations. However, insight into the operative catalyst involved in the photocatalytic process is hitherto missing. Herein, we show through a combination of theoretical and experimental studies that the perceived heterogeneous photocatalysis with Bi2O3 in the presence of alkyl bromides involves a homogeneous BinBrm species, which is the true photocatalyst operative in the reaction. Hence, Bi2O3 can be regarded as a precatalyst which is slowly converted in an active homogeneous photocatalyst. This work can also be of importance to mechanistic studies involving other semiconductor-based photocatalytic processes.

scholarly journals Loss of RET Promotes Mesenchymal Identity in Neuroblastoma Cells

Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1909
Author(s):  
Joachim T. Siaw ◽  
Jonatan L. Gabre ◽  
Ezgi Uçkun ◽  
Marc Vigny ◽  
Wancun Zhang ◽  
...  
Keyword(s):  
Genome Engineering ◽  
Neuroblastoma Cells ◽  
Gene Signature ◽  
Additional Insight ◽  
Downstream Target ◽  
Anaplastic Lymphoma ◽  
Extracellular Matrix Components ◽  
Transforming Gene ◽  
Insight Into

Aberrant activation of anaplastic lymphoma kinase (ALK) drives neuroblastoma (NB). Previous work identified the RET receptor tyrosine kinase (RTK) as a downstream target of ALK activity in NB models. We show here that ALK activation in response to ALKAL2 ligand results in the rapid phosphorylation of RET in NB cells, providing additional insight into the contribution of RET to the ALK-driven gene signature in NB. To further address the role of RET in NB, RET knockout (KO) SK-N-AS cells were generated by CRISPR/Cas9 genome engineering. Gene expression analysis of RET KO NB cells identified a reprogramming of NB cells to a mesenchymal (MES) phenotype that was characterized by increased migration and upregulation of the AXL and MNNG HOS transforming gene (MET) RTKs, as well as integrins and extracellular matrix components. Strikingly, the upregulation of AXL in the absence of RET reflects the development timeline observed in the neural crest as progenitor cells undergo differentiation during embryonic development. Together, these findings suggest that a MES phenotype is promoted in mesenchymal NB cells in the absence of RET, reflective of a less differentiated developmental status.

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