scholarly journals Computer simulated fragmentation arena test for assessing lethality and safety separation distances of explosive fragmentation ammunitions

2007 ◽  
Author(s):  
V. M. Gold ◽  
E. L. Baker ◽  
J. M. Pincay
Keyword(s):  
Explosive Fragmentation ◽  
Arena Test

Rearing substrate and space allowance influences locomotor play behaviour of dairy calves in an arena test

2014 ◽  
Vol 154 ◽  
pp. 8-14 ◽  
Author(s):  
Mhairi A. Sutherland ◽  
Gemma M. Worth ◽  
Karin E. Schütz ◽  
Mairi Stewart
Keyword(s):  
Dairy Calves ◽  
Play Behaviour ◽  
Arena Test

Assessing calf play behavior in an arena test

2012 ◽  
Vol 141 (3-4) ◽  
pp. 101-107 ◽  
Author(s):  
Erin M. Mintline ◽  
Sara L. Wood ◽  
Anne Marie de Passillé ◽  
Jeffrey Rushen ◽  
Cassandra B. Tucker
Keyword(s):  
Play Behavior ◽  
Arena Test

Explosive Fragmentation of Rock Masses with Heterogeneous Structure

2021 ◽  
pp. 135-138
Author(s):  
B.V. Ekvist ◽  
N.G. Barnov
Keyword(s):  
Geological Structure ◽  
Strength Properties ◽  
Open Pit ◽  
Heterogeneous Structure ◽  
Rock Masses ◽  
Variable Delays ◽  
Explosive Fragmentation ◽  
Complex Geological Structure ◽  
Technical Properties

A method to optimize drilling and blasting parameters with account of the physical and technical properties of rocks within the blasted block is proposed to improve the quality of blasting in open pit mines characterized by complex geological settings. The results of laboratory tests are provided that confirm improvement in the quality of rock sample crushing by blasting charges with variable delays and locations, depending on the strength properties of the samples, relative to blasting charges with unchanged parameters. The proposed method can be used in combination with GPR surveys of the rock mass. Explosive fragmentation of the rock masses with complex structures is characterized with a number of features caused by changes in the strength properties within the blasted block. In order to optimize the fragmentation efficiency of rock masses with complex geological structure, it is required to assess physical and technical properties of rocks and to determine their location and variations of the strength properties within the blasted block. It is possible to quickly assess the physical and technical properties of the blasted rocks using the surface georadar method. The outcome of this method is georeferencing of the reoradar data to the location and properties of the rocks to be blasted, along with the methodology of applying the georadar surveys, selection of the areal assembly type depending on the size and properties of detected jointing, and economic justification of applying this method. The novelty consists in linking the georadar data on the rocks to be blasted with drilling and blasting parameters.

scholarly journals Effect of Morphine Administration on Social and Non-Social Play Behaviour in Calves

Animals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 56 ◽  
Author(s):  
Mhairi Sutherland ◽  
Gemma Worth ◽  
Catherine Cameron ◽  
Else Verbeek
Keyword(s):  
Intravenous Injection ◽  
Affective State ◽  
Social Play ◽  
Play Behaviour ◽  
Morphine Administration ◽  
Positive Affective State ◽  
Arena Test

The objective of this study was to evaluate the effect of morphine on social and non‐socialplay behaviour in calves. Twelve calves experienced four treatments in a cross over 2 × 2 factorialdesign: Calves received an intravenous injection of morphine or saline 10 min prior to being testedindividually or in pairs in an arena for 20 min. Play behaviour was continuously recorded in thearena test. Lying times were recorded in the home pen. Cortisol concentrations were measuredbefore and after testing. In the arena test, calves given morphine tended to perform more social playevents than calves given saline, however, morphine administration had no effect on locomotor play.Calves given morphine spent less time lying than calves given saline during the first 4 h afterreturning to the home pen. Cortisol concentrations were suppressed in calves given morphine.Administration of morphine appeared to increase social play but had no effect on locomotor playin calves. This study highlights the importance of investigating different aspects of play behaviourin animals as some may be more indicative of a positive affective state than others. More studiesinvestigating the effects of morphine on play are needed to confirm the results found in this study.

Numerical Modeling of Fragmentation Characteristics of Explosive Fragmentation Munitions

2002 ◽  
Author(s):  
Vladimir M. Gold
Keyword(s):  
High Speed ◽  
Average Length ◽  
Three Dimensional ◽  
Fragmentation Model ◽  
Computational Technique ◽  
Entire Body ◽  
Detonation Products ◽  
Explosive Fragmentation ◽  
Break Up ◽  
The Moment

Numerical simulations of explosive fragmentation munitions presented in this work integrate three-dimensional axisymmetric hydrocode analyses with analytical fragmentation modeling. The developed analytical fragmentation model is based on the Mott’s theory of break-up of cylindrical “ring-bombs” (Mott, 1947), in which the average length of fragments is a function of the radius and velocity of the ring at the moment of break-up, and the mechanical properties of the metal. The fundamental assumption of the model is that the fragmentation occurs instantly throughout the entire body of the shell. Adopting Mott’s critical fracture strain concept (Mott, 1947), the moment of the shell break-up is identified in terms of the high explosive detonation products volume expansions, V/V0. The assumed fragmentation time determined from the high-speed photographic data of Pearson (1990) had been approximately three volume expansions, the fragmentation being defined as the instant at which the detonation products first appear as they emanate from the fractures in the shell. The newly developed computational technique is applied to both the natural and preformed explosive fragmentation munitions problems. Considering relative simplicity of the model, the accuracy of the prediction of fragment spray experimental data is rather remarkable.

Behavioural and physiological effects in sheep of a chronic stressor and a parasite challenge

1991 ◽  
Vol 42 (8) ◽  
pp. 1335 ◽  
Author(s):  
LR Fell ◽  
JJ Lynch ◽  
DB Adams ◽  
GN Hinch ◽  
RK Munro ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Challenge Infection ◽  
Parasitic Disease ◽  
Physiological Effects ◽  
Immunological Status ◽  
Plasma Cortisol Concentration ◽  
Chronic Stressor ◽  
Low Levels ◽  
Arena Test ◽  
Parasite Challenge

Mature Merino ewes, either at pasture (paddock) or in a feedlot situation (penned), were given a serial challenge infection with the gastric nematode parasite, Haemonchus contortus, and compared with control animals for their behaviour in an arena test, their plasma cortisol concentration and haematological and immunological status. Very low levels of infection resulted and parasitic disease was not evident. There were, however, significant effects on behaviour of both the challenge infection and the feedlot situation. The parasitic treatment resulted in a reduced distance between the sheep and the person in the arena test and also an increase in locomotor activity in the case of penned sheep. Overall, the penned animals displayed twice as much locomotor activity as paddock sheep. Mechanisms whereby a infectious challenge could affect sheep behaviour require further investigation.

Comment on “Scaling behavior in explosive fragmentation”

2002 ◽  
Vol 65 (4) ◽  
Author(s):  
J. A. Åström ◽  
R. P Linna ◽  
J. Timonen
Keyword(s):  
Scaling Behavior ◽  
Explosive Fragmentation
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