Experimental and Numerical Response of RC Walls with Discontinuities Under Cycling Loading

AbstractThe number of predators inhabiting nests of Hyphantria cunea Drury was recorded annually for 13 years in four areas in New Brunswick and two areas on the coast of Nova Scotia. The most common groups were the pentatomids and spiders, which sometimes reproduced within the nests, but the mean number per nest was low in relation to the number of H. cunea larvae in the colonies. The rate of predation on fifth-instar larvae was low. Small or timid predators appeared to prey largely on moribund larvae or small saprophagans during the principal defoliating instars of H. cunea.No relationship could be detected between the number of larvae reaching the fifth instar and the number of predators in the colony; nor could any functional or numerical response of the predators to either the initial number of larvae per colony or the population density of colonies be found. It is concluded that the influence of the nest-inhabiting predators is small and relatively stable, and may be treated as a constant in the development of models to explain the population dynamics of H. cunea.H. cunea is a pest in parts of Europe and Asia, where it has been accidentally introduced from North America. The introduction to other continents of the North American predator, Podisus maculiventiis (Say), is discussed briefly.

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Delayed numerical response of goshawks to population fluctuations of forest grouse

Oikos ◽

10.1111/j.0030-1299.2005.14066.x ◽

2005 ◽

Vol 111 (2) ◽

pp. 408-415 ◽

Cited By ~ 25

Author(s):

Risto Tornberg ◽

Erkki Korpimaki ◽

Sven Jungell ◽

Vitali Reif

Keyword(s):

Numerical Response ◽

Population Fluctuations

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Making inference from wildlife collision data: inferring predator absence from prey strikes

PeerJ ◽

10.7717/peerj.3014 ◽

2017 ◽

Vol 5 ◽

pp. e3014 ◽

Cited By ~ 2

Author(s):

Peter Caley ◽

Geoffrey R. Hosack ◽

Simon C. Barry

Keyword(s):

Prey Species ◽

Red Fox ◽

Prey Availability ◽

Numerical Response ◽

Practical Application ◽

Ecological Inference ◽

Predator Species ◽

New Approach ◽

Predictive Probability ◽

Irreducible Uncertainty

Wildlife collision data are ubiquitous, though challenging for making ecological inference due to typically irreducible uncertainty relating to the sampling process. We illustrate a new approach that is useful for generating inference from predator data arising from wildlife collisions. By simply conditioning on a second prey species sampled via the same collision process, and by using a biologically realistic numerical response functions, we can produce a coherent numerical response relationship between predator and prey. This relationship can then be used to make inference on the population size of the predator species, including the probability of extinction. The statistical conditioning enables us to account for unmeasured variation in factors influencing the runway strike incidence for individual airports and to enable valid comparisons. A practical application of the approach for testing hypotheses about the distribution and abundance of a predator species is illustrated using the hypothesized red fox incursion into Tasmania, Australia. We estimate that conditional on the numerical response between fox and lagomorph runway strikes on mainland Australia, the predictive probability of observing no runway strikes of foxes in Tasmania after observing 15 lagomorph strikes is 0.001. We conclude there is enough evidence to safely reject the null hypothesis that there is a widespread red fox population in Tasmania at a population density consistent with prey availability. The method is novel and has potential wider application.

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USE OF DIFFERENT SHAPED STEEL SLIT DAMPERS IN BEAM TO COLUMN CONNECTIONS OF STEEL FRAMES UNDER CYCLING LOADING

10.18057/ijasc.2018.14.2.7 ◽

2018 ◽

Keyword(s):

Steel Frames ◽

Cycling Loading

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NUMERICAL RESPONSE AND EFFICIENCY OF CONVERSION OF INGESTED FOOD OF PREDATOR Dicrodiplosis manihoti Harris, (DIPTERA : CECIDOMYIIDAE) FOR EGGS DENSITIES OF MEALY BUG Planococcus citri (Risso),(HEMIPTERA :PSEUDOCOCCIDAE) .

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v48i2.412 ◽

2017 ◽

Vol 48 (2) ◽

Author(s):

Al-Zubaidy & Al-Shammari

Keyword(s):

Conversion Efficiency ◽

Egg Production ◽

Prey Density ◽

Total Duration ◽

Numerical Response ◽

Planococcus Citri ◽

Food Conversion ◽

High Significance ◽

Larval Stages ◽

Food Conversion Efficiency

The results of numerical response showed to increasing rates of egg production for the predator female with prey density increases, noting of a positive correlation between the number of eggs lying by the female predator and prey density, Being 7, 13.1, 17 and 30 eggs/female during her life when making egg densities of prey 10, 20, 40 and 60 eggs/day during the period of development of Larval ages respectively. Statistical analysis results have pointed to the moral differences between those rates at 0.05 probability level. Food conversion efficiency was marked by ECI also increases with increasing density of prey . Food conversion efficiency to eggs by female predator increased in high densities of prey compared with low densities as well as reduced food efficiency with increasing density of prey where when lying densities and decreased when high densities prey. It also shortened the duration of phases three predator when prey density increases amounting to (2.74, 3.37, 9.15) and(1.62, 4.32, 5.04), (1.86, 2.82, 4.07) and (1.16 , 2.89, 3.42) consecutive days so that the total duration of Larval stage 15.26, 10.98, 8.75 and 7.47 days respectively with high significance deference. As well as high rates of predation 80, 74.24, 96.52 and 116.91 egg respectively and moral difference in egg consumption rates between larval stages as well as during the period of Larval stages at probability 0.05. survival rates also increased for the larval, pupal and adults stages when the density of the prey increased with high significance difference.

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