First Mass Capture of Black Snake Mackerel Nealotus tripes (Gempylidae)

2019 ◽  
Vol 59 (4) ◽  
pp. 566-571
Author(s):  
M. V. Nazarkin ◽  
O. A. Maznikova ◽  
A. M. Orlov
Keyword(s):  
Mass Capture

scholarly journals Combined Magnetohydrodynamic and Geometric Optimization of a Hypersonic Inlet

2009 ◽  
Vol 2009 ◽  
pp. 1-12 ◽  
Author(s):  
Kamesh Subbarao ◽  
Jennifer D. Goss
Keyword(s):  
Magnetic Field ◽  
Numerical Optimization ◽  
Splitting Method ◽  
Optimization Procedure ◽  
Geometric Optimization ◽  
Control Parameters ◽  
Flow Solution ◽  
Hypersonic Inlet ◽  
Mass Capture ◽  
The Magnetic Field

This paper considers the numerical optimization of a double ramp scramjet inlet using magnetohydrodynamic (MHD) effects together with inlet ramp angle changes. The parameter being optimized is the mass capture at the throat of the inlet, such that spillage effects for less than design Mach numbers are reduced. The control parameters for the optimization include the MHD effects in conjunction with ramp angle changes. To enhance the MHD effects different ionization scenarios depending upon the alignment of the magnetic field are considered. The flow solution is based on the Advection Upstream Splitting Method (AUSM) that accounts for the MHD source terms as well. A numerical Broyden-Flecher-Goldfarb-Shanno- (BFGS-) based procedure is utilized to optimize the inlet mass capture. Numerical validation results compared to published results in the literature as well as the outcome of the optimization procedure are summarized to illustrate the efficacy of the approach.

Design and Numerical Investigations on a Dual-Duct Variable Geometry RBCC Inlet

2020 ◽  
Vol 37 (2) ◽  
pp. 111-122 ◽  
Author(s):  
Xiaowei Liu ◽  
Lei Shil ◽  
Peijin Liu ◽  
Fei Qin ◽  
Guoqiang He
Keyword(s):  
Combined Cycle ◽  
High Mass ◽  
Variable Geometry ◽  
Status Transition ◽  
Flight Range ◽  
Operational Window ◽  
Mass Capture ◽  
Temperature Environment ◽  
Mach Numbers ◽  
High Mach

AbstractA widely applicable and variable geometry 2-D rocket based combined cycle (RBCC) inlet characterized by the dual-duct design is conceptually put forward. The inlet operates as dual-duct status in the low Mach range (0~4), and transits to single-flowpath status in the following high Mach range (4~7). It accomplishes operational status transition through an 8.0-degree ramp rotation and a 4.0-degree cowl rotation at Mach 4. Through numerical simulations on typical flight Mach numbers, the observed starting Mach number is 2.2, which provides a sufficient operational window for a smooth ejector-to-ramjet mode transition. The RBCC inlet achieves comprehensive high mass capture coefficients in the overall wide flight range, especially in the low speed regimes. Suitable Mach numbers satisfying various combustion requirements in different modes together with high total pressure recovery coefficients are also obtained since the physical throat areas, compression angles, and the corresponding contraction ratios can be adjusted by a large margin through very limited rotations. The variable geometry scheme is not only feasible for practical realizations, but is also simple to arrange the dynamic sealing issues in a low-temperature environment in the RBCC engine.

MASS CAPTURE AND ANESTHESIA OF AUSTRALIAN BRIDLED NAILTAIL WALLABIES (ONYCHOGALEA FRAENATA) WITH THE USE OF MEDETOMIDINE AND KETAMINE

2014 ◽  
Vol 50 (4) ◽  
pp. 858-863 ◽  
Author(s):  
Wayne S. J. Boardman ◽  
Charles G. Caraguel ◽  
Sarah Gill ◽  
Kerryn Herman ◽  
Margaret-Mary McEwen ◽  
...  
Keyword(s):  
Mass Capture

Numerical Simulation on Air Mass Capture Control of Hypersonic Inlet by Laser Energy

2014 ◽  
Vol 644-650 ◽  
pp. 1470-1473 ◽  
Author(s):  
Qian Li ◽  
Yan Ji Hong ◽  
Wei Zhao ◽  
Dian Kai Wang
Keyword(s):  
Hypersonic Flow ◽  
Laser Power ◽  
Laser Energy ◽  
Air Mass ◽  
Capture Ratio ◽  
Princeton University ◽  
Hypersonic Inlet ◽  
Mass Capture ◽  
Energy Addition ◽  
Numerical Program

Mechanism of hypersonic inlet performance promoting by “virtual cowl” induced by laser energy is introduced, and the physical model of interaction between laser energy and shocks in hypersonic flow field is established. Through comparing results in this paper with the work performed by Macheret et al.(Princeton University) and analyzing effects of laser energy deposited in hypersonic flow, numerical program and the feasibility of model are validated. At Mach 6, with no laser energy addition, air mass capture ratioKmis 71.87% in this paper, whileKmis 73.17% in the reference. Energy addition module can simulate the formation of shocks induced by laser energy, and the interaction process between laser energy and compression ramp shocks properly. Curves of mass capture ratioKmagrees well with that of the reference.Kmis a little higher than data in the reference, but the variable trend is consistent with each other when laser power is 1kW. When laser power is 0.5kW,Kmvaries a little, and the peak value is 77.36%, which only increases 7.64%, while the value is 7.28% in the reference.

Indicator species analysis as a test of non-random distribution of species in the context of marine protected areas

2002 ◽  
Vol 29 (3) ◽  
pp. 385-390 ◽  
Author(s):  
David Mouillot ◽  
Jean-Michel Culioli ◽  
Thang Do Chi
Keyword(s):  
Indicator Species ◽  
Marine Reserve ◽  
Randomization Test ◽  
Conservation Area ◽  
Data Set ◽  
New Approach ◽  
Indicator Value ◽  
Mass Capture ◽  
Species Analysis ◽  
Species Being

Species are identified as bioindicators when their presence or abundance within sites of a particular habitat or a conservation area are high. Dufrêne and Legendre (1997), Ecological Monographs 67: 345–366, proposed the use of a flexible asymmetrical approach to detect indicator species and species assemblages characterizing groups of sites, the indicator value for each species being subsequently tested by randomization. Although the advantages of these methods in comparison to other multivariate or two-way indicator species analyses have been demonstrated, relatively few ecological studies have made use of them. The aim of the present study was to demonstrate the advantages of the indicator species test using a data set generated by traditional fisheries activities at four areas in the Bonifacio Strait Marine Reserve, Corsica, France. ANOVA, Kruskal-Wallis and another randomization test were also performed on the same data set. Of the 54 species caught in the fishing nets, the indicator species analyses identified 19 species for which the indicator value was significant for a given area, whereas the a posteriori Tukey test for ANOVA detected only 12 species for which the mass capture per unit effort was significantly greater for a given area. The efficiency of this new approach within the framework of conservation and marine reserve studies is demonstrated by focusing on three species (Sciaena umbra, Palinurus elephas and Maja verrucosa).

Numerical simulations of the flow through the inlet and isolator of a Mach 4 dual mode scramjet

2012 ◽  
Vol 116 (1182) ◽  
pp. 833-846 ◽  
Author(s):  
S. Janarthanam ◽  
V. Babu
Keyword(s):  
Experimental Data ◽  
Numerical Simulations ◽  
Three Dimensional ◽  
Pressure Rise ◽  
Dual Mode ◽  
Flow Distortion ◽  
Capture Ratio ◽  
Boundary Interaction ◽  
Numerical Predictions ◽  
Mass Capture

Abstract Results from numerical simulations of the three dimensional flow in the intake-isolator of a dual mode scramjet are presented. The FANS calculations have utilised the SST k -ω turbulence model. The effect of cowl length and cowl convergence angle on the inlet mass capture ratio, flow distortion, shock strength and pressure rise are studied in detail. Three cowl lengths and four or five cowl convergence angles for each cowl length are considered. The predicted values of the dimensionless wall static pressure and inlet mass capture ratio are compared with experimental data reported in the literature. The numerical predictions are shown to agree well with the experimental data. In addition, details of the flow field such as shocks, expansion fans and shock boundary interaction are also captured accurately. Inlet unstart is also demonstrated for one case.

scholarly journals EFFECT OF COMMUNITY BASED AREA-WIDE FRUIT FLY SUPPRESSION ON BACTROCERA DORSALIS POPULATION IN ORANGE ORCHARDS IN MUHEZA DISTRICT TANZANIA

2016 ◽  
Vol 4 (9) ◽  
pp. 39-44
Author(s):  
ZuberiSingano Seguni
Keyword(s):  
Fruit Fly ◽  
Fruit Flies ◽  
Methyl Eugenol ◽  
Bactrocera Dorsalis ◽  
Large Area ◽  
Community Based ◽  
Simultaneous Application ◽  
Mass Capture ◽  
Crop Area ◽  
Large Crop

A community-based area wide fruit fly suppression exercise involving simultaneous application by farmers of methyl eugenol-mediated mass capture of males of Bactrocera dorsalis fruit fly, crop sanitation by burial of fallen fruits and SUCCESS bait (GF 121)spot application of citrus tree crowns, was undertaken in three villages in Muheza district, Tanga region north eastern Tanzania. Male fruit fly numbers in methyl eugenol traps dropped significantly following application of the treatments from 970 flies per trap per week before application of treatments in July 2011 to 100 and 46 flies six and nine months after treatments at Kwabada village; 200 flies per trap per week before to 34 and one flies after treatment at Kwemsaa village and from 800 flies before to 64 and 50 flies per trap per week during the same period at Mlingano village. However, a fall occurred also in untreated orchards indicating a possible spill-over effect of the treatments due to the large area covered. Moreover, the treated areas might have acted as a sink that drew fruit flies from neighbouring untreated orchards into it. The drastic fall in trapped males may be associated with the effect of the treatments in reducing the number of flies so that fewer were available to fly into the traps. The collective and simultaneous application by farmers of fruit fly suppression over a large crop area is a robust strategy to manage fruit flies in citrus and other fruits orchards such as mango. The results suggest that farmers can successfully implement area-wide fruit fly suppression in smallholder citrus systems.

scholarly journals Can Estivation Preferences Be Used to Develop Novel Management Tools against Invasive Mediterranean Snails?

Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1118
Author(s):  
Priscillia Hanache ◽  
Thierry Thomann ◽  
Valerie Caron ◽  
Gaylord A. Desurmont
Keyword(s):  
Field Conditions ◽  
Snail Species ◽  
Management Tools ◽  
Density Dependent ◽  
Mass Capture ◽  
Choice Tests ◽  
Summer Temperatures ◽  
Theba Pisana ◽  
Terrestrial Snails ◽  
Dry Climates

Terrestrial snails that live in hot and dry climates have developed strategies to cope with high summer temperatures. Several species estivate during the warmest months of the years by resting on vertical supports, typically in groups. Understanding how snails choose their estivation sites and aggregate may lead to the development of new management tools in areas where these snails are invasive. Here, we investigated the preferences of four snail species for vertical supports varying in widths and heights under laboratory and field conditions, and tested whether the presence of conspecifics or snails of other species affected these preferences. The results show that the snails strongly preferred wider supports in laboratory dual-choice tests, and one species (Theba pisana) showed a consistent preference for taller supports as well. These results were confirmed in the field, where more snails were found on wider and taller supports 24 h after being placed in test quadrats. The percentage of snails found in groups on a support was strongly density-dependent. The presence of conspecifics or their mucus did not affect the choices of the snails, nor did the presence of snails of other species or their mucus. Taken together, these results could lead to the development of attractive supports that could be used to mass-capture snails in the field.

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