scholarly journals On the total loss probability of service stages in series

1990 ◽  
Vol 22 (1) ◽  
pp. 260-262
Author(s):  
P.-J. Courtois
Keyword(s):  
Simple Model ◽  
Loss Rate ◽  
Loss Probability ◽  
Total Loss ◽  
Finite Queues ◽  
In Series

The problem addressed here is related to the minimization of the total loss probability in series of finite queues at which customers are rejected if the waiting capacity is exceeded. More precisely, one is concerned with the question of determining whether or not there may exist conditions under which an increase of the loss rate at one queue, e.g. at the most upstream one, could result in a decrease of the total loss rate throughout the whole network. The answer obtained in the context of a simple model is negative.

scholarly journals On the total loss probability of service stages in series

1990 ◽  
Vol 22 (01) ◽  
pp. 260-262
Author(s):  
P.-J. Courtois
Keyword(s):  
Simple Model ◽  
Loss Rate ◽  
Loss Probability ◽  
Total Loss ◽  
Finite Queues ◽  
In Series

The problem addressed here is related to the minimization of the total loss probability in series of finite queues at which customers are rejected if the waiting capacity is exceeded. More precisely, one is concerned with the question of determining whether or not there may exist conditions under which an increase of the loss rate at one queue, e.g. at the most upstream one, could result in a decrease of the total loss rate throughout the whole network. The answer obtained in the context of a simple model is negative.

Minimization of the total loss rate for two finite queues in series

1991 ◽  
Vol 39 (11) ◽  
pp. 1651-1661 ◽  
Author(s):  
P.-J. Courtois ◽  
G. Scheys
Keyword(s):  
Loss Rate ◽  
Total Loss ◽  
Finite Queues ◽  
In Series ◽  
Queues In Series

scholarly journals Characterization and Modelling of Various Sized Mountain Bike Tires and the Effects of Tire Tread Knobs and Inflation Pressure

2020 ◽  
Vol 10 (9) ◽  
pp. 3156 ◽  
Author(s):  
Andrew Dressel ◽  
James Sadauckas
Keyword(s):  
Simple Model ◽  
Lateral Stiffness ◽  
Tire Model ◽  
Laboratory Measurements ◽  
Inflation Pressure ◽  
Mountain Bike ◽  
Basic Model ◽  
Radial Stiffness ◽  
In Series ◽  
Distinguishing Features

Mountain bikes continue to be the largest segment of U.S. bicycle sales, totaling some USD 577.5 million in 2017 alone. One of the distinguishing features of the mountain bike is relatively wide tires with thick, knobby treads. Although some work has been done on characterizing street and commuter bicycle tires, little or no data have been published on off-road bicycle tires. This work presents laboratory measurements of inflated tire profiles, tire contact patch footprints, and force and moment data, as well as static lateral and radial stiffness for various modern mountain bike tire sizes including plus size and fat bike tires. Pacejka’s Motorcycle Magic Formula tire model was applied and used to compare results. A basic model of tire lateral stiffness incorporating individual tread knobs as springs in parallel with the overall tread and the inflated carcass as springs in series was derived. Finally, the influence of inflation pressure was also examined. Results demonstrated appreciable differences in tire performance between 29 × 2.3”, 27.5 × 2.8”, 29 × 3”, and 26 × 4” knobby tires. The proposed simple model to combine tread knob and carcass stiffness offered a good approximation, whereas inflation pressure had a strong effect on mountain bike tire behavior.

scholarly journals Radio Emission from WR Stars

1982 ◽  
Vol 99 ◽  
pp. 221-224 ◽  
Author(s):  
David E. Hogg
Keyword(s):  
Simple Model ◽  
Radio Emission ◽  
Mass Loss ◽  
Flux Density ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Large Array ◽  
Radio Observations ◽  
Very Large Array

In principle radio observations of WR stars offer the best possibility of determining the rate of mass loss, since for a simple model of the extended atmosphere the mass loss rate depends primarily on quantities—the flux density, the velocity, and the distance—which are observable (Barlow 1979). Until now, detections of Wolf-Rayet stars have been limited by the sensitivity and resolution of available telescopes. The advent of the Very Large Array makes a search for emission from a large number of these stars feasible.

Task Switching as a Two-Stage Decision Process

2006 ◽  
Vol 95 (5) ◽  
pp. 3146-3153 ◽  
Author(s):  
N. Sinha ◽  
J.T.G. Brown ◽  
R.H.S. Carpenter
Keyword(s):  
Decision Making ◽  
Simple Model ◽  
Task Switching ◽  
Decision Process ◽  
Time Behavior ◽  
Complex Situation ◽  
Linear Approach ◽  
Plausible Model ◽  
In Series ◽  
Underlying Mechanisms

Saccades represent decisions, and the study of their latency has led to a neurally plausible model of the underlying mechanisms, LATER (Linear Approach to Threshold with Ergodic Rate), that can successfully predict reaction time behavior in simple decision tasks, with fixed instructions. However, if the instructions abruptly change, we have a more complex situation, known as task switching. Psychologists' explanations of the phenomena of task switching have so far tended to be qualitative rather than quantitative, and not intended to relate particularly clearly to existing models of decision making or to likely neural implementations. Here, we investigated task switching using a novel saccadic task: we presented the instructions by stimulus elements identical to those of the task itself, allowing us to compare decisions about instructions with decisions in the actual task. Our results support a relatively simple model consisting of two distinct LATER processes in series: the first detects the instruction, the second implements it.

A Series Pressure Drop Representation for Flow Through Orifice Tubes

2008 ◽  
Vol 130 (5) ◽  
Author(s):  
T. A. Jankowski ◽  
E. N. Schmierer ◽  
F. C. Prenger ◽  
S. P. Ashworth
Keyword(s):  
Experimental Data ◽  
Reynolds Number ◽  
Simple Model ◽  
Pressure Drop ◽  
Diameter Ratio ◽  
Pressure Drops ◽  
In Series ◽  
Orifice Flow ◽  
Flow Through ◽  
Length To Diameter Ratio

A simple model is developed here to predict the pressure drop and discharge coefficient for incompressible flow through orifices with length-to-diameter ratio greater than zero (orifice tubes) over wide ranges of Reynolds number. The pressure drop for flow through orifice tubes is represented as two pressure drops in series; namely, a pressure drop for flow through a sharp-edged orifice in series with a pressure drop for developing flow in a straight length of tube. Both of these pressure drop terms are represented in the model using generally accepted correlations and experimental data for developing flows and sharp-edged orifice flow. We show agreement between this simple model and our numerical analysis of laminar orifice flow with length-to-diameter ratio up to 15 and for Reynolds number up to 150. Agreement is also shown between the series pressure drop representation and experimental data over wider ranges of Reynolds number. Not only is the present work useful as a design correlation for equipment relying on flow through orifice tubes but it helps to explain some of the difficulties that previous authors have encountered when comparing experimental observation and available theories.

Assessing tag loss and survival probabilities in green turtles (Chelonia mydas) nesting in Malaysia

2017 ◽  
Vol 98 (4) ◽  
pp. 961-972 ◽  
Author(s):  
Hideaki Nishizawa ◽  
Juanita Joseph ◽  
Vicki Yii-Ching Chew ◽  
Hock-Chark Liew ◽  
Eng-Heng Chan
Keyword(s):  
Confidence Interval ◽  
Survival Probability ◽  
Loss Rate ◽  
Chelonia Mydas ◽  
Loss Probability ◽  
Population Status ◽  
Mark Recapture ◽  
Survival Probabilities ◽  
Green Turtles ◽  
Tag Loss

The loss of external tags is one of the biggest problems in mark-recapture research. An evaluation of tag loss is therefore required to improve tagging methodology, select appropriate tag types, and accurately estimate population status and dynamics. We estimated tag loss probability of double-tagged green turtles (Chelonia mydas) nesting at Redang Island, Malaysia (05°49′ N 103°00′ E), from 1993–2014. For both titanium and Inconel tags, we found a tag loss pattern with a high initial tag loss rate that decreased to an asymptote near a constant value above zero. The initial tag loss probability for titanium tags was higher than for Inconel tags, and titanium tags were lost earlier than Inconel tags in more individuals when both types of tags were attached. In addition, comparison of the tag loss probability of Inconel tags attached during the period when tagging staff changed every year to that when senior tagging staff were not changed, indicated that lack of consistency in tagging staff affected the application of at least one of two Inconel tags. Estimated tag loss probability was incorporated into a recapture model, and annual survival probability was estimated to be 0.893 (95% confidence interval: 0.857–0.921).

Design and Experiment of Hand-Push Vibration Picking Machine of Lowbush Blueberry

2014 ◽  
Vol 620 ◽  
pp. 375-380 ◽  
Author(s):  
Yu Dong Bao ◽  
Yan Ling Guo
Keyword(s):  
Vibration Frequency ◽  
Loss Rate ◽  
The Body ◽  
Total Loss ◽  
Green Fruit ◽  
Early Stages ◽  
Technical Requirements ◽  
Important Link ◽  
Lowbush Blueberry ◽  
Automation Level

As plants of lowbush blueberry are widely cultivated, picking of blueberry has become an important link in the chain of blueberry industry. At present, research of domestic machinery of blueberry picking is still in early stages. Mechanical and automation level of blueberry picking are enriched, through research of picking machine of lowbush blueberry. The research has the vital significance to the development of blueberry industry. To improve picking efficiency and reduce total loss rate of green fruit, mechanism of picking is analyzed. Fruit, which has certain representativeness in the variety, is researched. Picking force and vibration frequency of plants are obtained and work principle is determined. Structures of vibrating picking and fruit collection and the body of the machine are designed. Parameters of structure size and working are determined, with which the machine is manufactured. Plan of experiment is designed and experiment of picking is done in the season blueberries are most ripe. Result indicates structure of blueberry picking machine is reasonable. Picking force and vibration frequency are effective. Compared with that of manual picking, efficiency of mechanical picking is high, which meets technical requirements of blueberry machinery.

scholarly journals A simple model for a radiatively driven metallic wind in A0 stars

1994 ◽  
Vol 162 ◽  
pp. 492-493
Author(s):  
J. Babel
Keyword(s):  
Simple Model ◽  
Mass Loss ◽  
Loss Rate ◽  
Main Sequence ◽  
Frictional Heating ◽  
Mass Loss Rate

Litle is known about the wind of main sequence A7 to B4 stars. We here investigate the case of a radiatively driven wind for an A0 star and obtain stringent limits on the mass loss rate. We also show that frictional heating lead to the presence of a chromospheric region very near the photosphere.

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