scholarly journals Hard versus soft impact modeling of vibro-impact systems with a moving base

2021 ◽  
Author(s):  
Andrzej Okolewski ◽  
Barbara Blazejczyk-Okolewska
Keyword(s):  
Energy Dissipation ◽  
High Rate ◽  
Impact Model ◽  
Equal Energy ◽  
Moving Base ◽  
Low Stiffness ◽  
Impact Models ◽  
Collision Models ◽  
Low Rate

AbstractSoft and hard impact models applied to modeling of vibro-impact systems with a moving base are discussed. The conditions under which two collision models are equivalent in terms of equal energy dissipation are derived. These conditions differ from those presented in the literature. It is shown that in the case of a stiff, harmonically moving base with a low rate of energy dissipation, both methods yield the same results, but an application of the soft impact model to either the base with low stiffness or even the stiff base with a high rate of energy dissipation leads to different results from the ones for the hard impact model.

A Note on Groove Depth Changes Without Wear

1980 ◽  
Vol 8 (1) ◽  
pp. 10-12
Author(s):  
F. C. Brenner
Keyword(s):  
Weight Loss ◽  
Wear Test ◽  
Groove Depth ◽  
High Rate ◽  
Weight Changes ◽  
Wear Rates ◽  
Weight Loss Method ◽  
Loss Method ◽  
And Storage ◽  
Low Rate

Abstract Tread wear rates during first wear measured by groove depth and weight changes do not always agree. Sometimes, the groove depth method shows a high rate and the weight loss method a low rate. Reported here are experiments designed to determine if grooves show depth changes without wear. Four tires were measured before mounting on a wheel, after mounting and inflation, and after inflation and storage. The mounted and inflated tires showed shallower shoulder grooves and deeper center grooves than the unmounted tires. In a second experiment, tires were measured immediately after a tread wear test and then stored mounted for two weeks before remeasuring. Each groove became deeper, and there was no change in the crown radius of any tire.

scholarly journals Combining High- and Low-Rate Geodetic Data Analysis for Unveiling Rapid Magma Transfer Feeding a Sequence of Violent Summit Paroxysms at Etna in Late 2015

2021 ◽  
Vol 11 (10) ◽  
pp. 4630
Author(s):  
Alessandro Bonforte ◽  
Flavio Cannavò ◽  
Salvatore Gambino ◽  
Francesco Guglielmino
Keyword(s):  
Ground Deformation ◽  
High Rate ◽  
Rate Data ◽  
Scale Analysis ◽  
Feeding System ◽  
Magma Sources ◽  
Mt Etna ◽  
Multi Temporal ◽  
Gnss Measurements ◽  
Low Rate

We propose a multi-temporal-scale analysis of ground deformation data using both high-rate tilt and GNSS measurements and the DInSAR and daily GNSS solutions in order to investigate a sequence of four paroxysmal episodes of the Voragine crater occurring in December 2015 at Mt. Etna (Italy). The analysis aimed at inferring the magma sources feeding a sequence of very violent eruptions, in order to understand the dynamics and to image the shallow feeding system of the volcano that enabled such a rapid magma accumulation and discharge. The high-rate data allowed us to constrain the sources responsible for the fast and violent dynamics of each paroxysm, while the cumulated deformation measured by DInSAR and daily GNSS solutions, over a period of 12 days encompassing the entire eruptive sequence, also showed the deeper part of the source involved in the considered period, where magma was stored. We defined the dynamics and rates of the magma transfer, with a middle-depth storage of gas-rich magma that charges, more or less continuously, a shallower level where magma stops temporarily, accumulating pressure due to the gas exsolution. This machine-gun-like mechanism could represent a general conceptual model for similar events at Etna and at all volcanoes.

PARAMETERS FOR DYNAMIC SIMULATION OF W ASTEW ATER TREATMENT PLANTS WITH HIGH-RATE AND LOW-RATE ACTIVATED SLUDGE TANKS

1994 ◽  
Vol 30 (4) ◽  
pp. 211-214 ◽  
Author(s):  
E. Brands ◽  
M. Liebeskind ◽  
M. Dohmann
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Dynamic Simulation ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
High Rate ◽  
Yield Coefficient ◽  
Municipal Wastewater Treatment ◽  
Municipal Wastewater Treatment Plants ◽  
Low Rate

This study shows a comparison of important parameters for dynamic simulation concerning the highrate and low-rate activated sludge tanks of several municipal wastewater treatment plants. The parameters for the dynamic simulation of the single-stage process are quite well known, but parameters for the high-ratellow-rate activated sludge process are still missi ng, although a considerable number of wastewater treatment plants are designed and operated that way. At present any attempt to simulate their operation is restricted to the second stage due to missing data concerning growth rate, decay rate, yield coefficient and others.

Noncontingent Nonreinforcement of a Response as the Aversive Event in a Cer Paradigm

1971 ◽  
Vol 29 (3_suppl) ◽  
pp. 1196-1198 ◽  
Author(s):  
Richard S. Calef ◽  
Richard A. Kaufman ◽  
Ronald N. Bone ◽  
Steven A. Werk
Keyword(s):  
Reinforcement Schedule ◽  
Present Experiment ◽  
High Density ◽  
High Rate ◽  
Aversive Event ◽  
Necessary Condition ◽  
Facilitation Effect ◽  
Response Facilitation ◽  
Early Training ◽  
Low Rate

The present experiment investigated the effects of noncontingent nonreinforcement as the aversive event in a CER paradigm. The results showed a significant response-facilitation effect during early training, but none during later training with a high rate-producing, high-density reinforcement schedule. The present results imply that a low rate-producing, high-density reinforcement schedule is not a necessary condition for response facilitation.

scholarly journals Comparison of Vocal Vibration-Dose Measures for Potential-Damage Risk Criteria

2015 ◽  
Vol 58 (5) ◽  
pp. 1425-1439 ◽  
Author(s):  
Ingo R. Titze ◽  
Eric J. Hunter
Keyword(s):  
Energy Dissipation ◽  
Dose Calculations ◽  
Equal Energy ◽  
Vocal Fold Vibration ◽  
Risk Criterion ◽  
Time Cycle ◽  
Vocal Intensity ◽  
Potential Damage ◽  
Voice Use ◽  
Damage Risk

Purpose Schoolteachers have become a benchmark population for the study of occupational voice use. A decade of vibration-dose studies on the teacher population allows a comparison to be made between specific dose measures for eventual assessment of damage risk. Method Vibration dosimetry is reformulated with the inclusion of collision stress. Two methods of estimating amplitude of vocal-fold vibration are compared to capture variations in vocal intensity. Energy loss from collision is added to the energy-dissipation dose. An equal-energy-dissipation criterion is defined and used on the teacher corpus as a potential-damage risk criterion. Results Comparison of time-, cycle-, distance-, and energy-dose calculations for 57 teachers reveals a progression in information content in the ability to capture variations in duration, speaking pitch, and vocal intensity. The energy-dissipation dose carries the greatest promise in capturing excessive tissue stress and collision but also the greatest liability, due to uncertainty in parameters. Cycle dose is least correlated with the other doses. Conclusion As a first guide to damage risk in excessive voice use, the equal-energy-dissipation dose criterion can be used to structure trade-off relations between loudness, adduction, and duration of speech.

Effects of Deformation Twinning on Energy Dissipation in High Rate Deformed Zirconium

2007 ◽  
Vol 38 (12) ◽  
pp. 2916-2927 ◽  
Author(s):  
H.A. Padilla ◽  
C.D. Smith ◽  
J. Lambros ◽  
A.J. Beaudoin ◽  
I.M. Robertson
Keyword(s):  
Energy Dissipation ◽  
Deformation Twinning ◽  
High Rate

scholarly journals Earthquake response of adjacent structures with viscoelastic and friction dampers

2015 ◽  
Vol 42 (4) ◽  
pp. 277-289
Author(s):  
Miodrag Zigic ◽  
Nenad Grahovac
Keyword(s):  
Energy Dissipation ◽  
Fractional Derivatives ◽  
Viscoelastic Body ◽  
Dynamical Behaviour ◽  
Friction Damper ◽  
Adjacent Structures ◽  
Moving Base ◽  
Earthquake Model ◽  
Horizontal Ground Motion ◽  
Fractional Zener Model

We study the seismic response of two adjacent structures connected with a dry friction damper. Each of them consists of a viscoelastic rod and a rigid block, which can slide without friction along the moving base. A simplified earthquake model is used for modeling the horizontal ground motion. Energy dissipation is taken by the presence of the friction damper, which is modeled by the set-valued Coulomb friction law. Deformation of viscoelastic rods during the relative motion of the blocks represents another way of energy dissipation. The constitutive equation of a viscoelastic body is described by the fractional Zener model, which includes fractional derivatives of stress and strain. The problem merges fractional derivatives as non-local operators and theory of set-valued functions as the non-smooth ones. Dynamical behaviour of the problem is governed by a pair of coupled multi-valued differential equations. The posed Cauchy problem is solved by use of the Gr?nwald-Letnikov numerical scheme. The behaviour of the system is analyzed for different values of system parameters.

Scenario Prediction of China’s Natural Gas Consumption and Carbon Emissions in the Next Ten Years

2021 ◽  
Vol 16 (3) ◽  
pp. 569-587
Author(s):  
Chunzi Wang ◽  
◽  
Mingxiong Zhu ◽  
Keyword(s):  
Economic Growth ◽  
Natural Gas ◽  
Emission Reduction ◽  
Carbon Emission ◽  
Gas Production ◽  
High Rate ◽  
Carbon Emission Reduction ◽  
Gas Consumption ◽  
Natural Gas Consumption ◽  
Low Rate

Based on Johansen Cointegration Test, this paper sheds light on the long-run equilibrium relationship between natural gas consumption, gas production, and GDP in China. Three different natural gas demand scenarios of low, medium and high rates in the next ten years are considered, and a Neural Network Autoregression Model is used to predict the future carbon dioxide emission. We conclude: (1) In all three scenarios, the growth rates of natural gas consumption are all higher than those of natural gas production, while the gap between demand and domestic supply will gradually turn broader and China will largely rely on imports ; (2) In the scenario of low-rate economic growth, natural gas consumption will grow slowly, and it will be difficult to realize the carbon emission reduction targets by 2030 due to low-rate substitution of natural gas for coal; (3) If medium-rate to high-rate economic growth sustains, coupled with rapid increase in natural gas consumption and production, China’s Carbon Emission Reduction Targets for 2030 can be achieved with high-rate substitution of natural gas for coal.

China's Population Aging and New Urbanization

2016 ◽  
pp. 106-124
Author(s):  
Mingxing Chen ◽  
Hua Zhang ◽  
Yinghua Gong
Keyword(s):  
Chinese Population ◽  
Population Aging ◽  
High Rate ◽  
Natural Growth ◽  
The Sustainable Development ◽  
Aged Population ◽  
The World ◽  
Long Time ◽  
Low Rate ◽  
New Urbanization

In recent years, fast demographic transition, urbanizationand socio-economic development in China draws attention of the world. The reproduction type of Chinese population has changed from “high rate of birth, high rate of death, and low rate of natural growth” to “low rate of birth, low rate of death, and low rate of natural growth”, which promotes the population transition, bringing the problems of aging of population. In China, the scale of aged population is large, and its developing speed is fast. Along with the increasing of aged population in China, the advantage of labor quantity in China is challenged. China regards new urbanization as the important work content of state in the future for a long time, providing a large opportunity for the study in the field of urbanization. For China, new urbanization plan is just a beginning. The sustainable development of Chinese population and urbanization has important meaning in the world.

scholarly journals An Area Economic Development Impact Model for Extension Application

1978 ◽  
Vol 10 (1) ◽  
pp. 89-93 ◽  
Author(s):  
James R. Nelson
Keyword(s):  
Economic Development ◽  
Manufacturing Firms ◽  
Local Economy ◽  
Service Firms ◽  
Economic Base ◽  
Impact Model ◽  
Goods And Services ◽  
Transportation Finance ◽  
Impact Models ◽  
Local Firms

Most area economic development impact models are based on the premise that the basis of an area economy is a group of local firms which produce goods and services for sale outside the area. Agriculture, mining, and manufacturing firms typically make up a large part of such a group of exporting or basic firms. However, in most communities and some larger areas, many service firms (wholesale, retail, transportation, finance, medical, utilities) sell some of their products outside the local economy. These exports are part of the area's economic base. That portion of the output of the firms in an area which goes to satisfy local demands is nonbasic output. Area employment used to produce basic and nonbasic goods and services can be classified similarly as basic and nonbasic employment, respectively.

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