Статті в журналах: "Extinction criterion"

1

Gorea, Andrei, and Dov Sagi. "Natural extinction: A criterion shift phenomenon." Visual Cognition 9, no. 8 (November 2002): 913–36. http://dx.doi.org/10.1080/13506280143000638.

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2

Ridler-Rowe, C. J. "Extinction times for certain predator–prey processes." Journal of Applied Probability 25, no. 3 (September 1988): 612–16. http://dx.doi.org/10.2307/3213988.

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Finiteness of mean extinction times for certain predator-prey models has been established by Hitchcock (1986) with the aid of a criterion of Reuter (1957). Using this criterion and a ‘minimisation' lemma this note shows that the mean extinction times tend to zero as the combined initial population of predators and prey becomes large.

3

Ridler-Rowe, C. J. "Extinction times for certain predator–prey processes." Journal of Applied Probability 25, no. 03 (September 1988): 612–16. http://dx.doi.org/10.1017/s0021900200041310.

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Finiteness of mean extinction times for certain predator-prey models has been established by Hitchcock (1986) with the aid of a criterion of Reuter (1957). Using this criterion and a ‘minimisation' lemma this note shows that the mean extinction times tend to zero as the combined initial population of predators and prey becomes large.

4

Shiozawa, Yuichi. "Extinction of branching symmetric α-stable processes". Journal of Applied Probability 43, № 4 (грудень 2006): 1077–90. http://dx.doi.org/10.1239/jap/1165505209.

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We give a criterion for extinction or local extinction of branching symmetric α-stable processes in terms of the principal eigenvalue for time-changed processes of symmetric α-stable processes. Here the branching rate and the branching mechanism are spatially dependent. In particular, the branching rate is allowed to be singular with respect to the Lebesgue measure. We apply this criterion to some branching processes.

5

Shiozawa, Yuichi. "Extinction of branching symmetric α-stable processes". Journal of Applied Probability 43, № 04 (грудень 2006): 1077–90. http://dx.doi.org/10.1017/s0021900200002448.

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We give a criterion for extinction or local extinction of branching symmetric α-stable processes in terms of the principal eigenvalue for time-changed processes of symmetric α-stable processes. Here the branching rate and the branching mechanism are spatially dependent. In particular, the branching rate is allowed to be singular with respect to the Lebesgue measure. We apply this criterion to some branching processes.

6

Katta, V. R., T. R. Meyer, M. S. Brown, J. R. Gord, and W. M. Roquemore. "Extinction criterion for unsteady, opposing-jet diffusion flames." Combustion and Flame 137, no. 1-2 (April 2004): 198–221. http://dx.doi.org/10.1016/j.combustflame.2004.02.004.

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7

Zhai, Jinan, Shangyu Zhang, and Linhua Liu. "Extinction and Independent Scattering Criterion for Clusters of Spherical Particles Embedded in Absorbing Host Media." Photonics 10, no. 7 (July 5, 2023): 782. http://dx.doi.org/10.3390/photonics10070782.

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In practical applications, the independent scattering approximation (ISA) is widely used to analyze light transfer in nanoparticle systems. However, the traditional independent scattering criterion is obtained under the assumption that the host medium surrounding particles is nonabsorbing, and thus may be invalid in certain circumstances. In this work, to explore the applicability of the ISA for small particles in absorbing host media, we calculate the extinction efficiency of particle clusters by direct solutions of macroscopic Maxwell equations. Using the far-field and distance-independent definitions of extinction, the computational efficiency multi-sphere method is applied for particle clusters in absorbing host, and its accuracy is verified with the discrete dipole approximation method. It is well known that for small particles, the dependent scattering in transparent host always enhances the extinction of the cluster and the criterion for the ISA is nearly independent of the particle refractive index and particle size. We show, however, that when the host medium is absorbing, the dependent scattering between particles can lead to a decreased or even negative extinction, and thus the ISA criterion depends on the particle refractive index, size, and host medium absorption index. In this result, the generalized criteria for absorbing host media may differ significantly from the conventional ones for transparent host media. The results can provide guidance in solving problems related to light transfer in nanoparticle systems, particularly in the presence of absorption in the host medium.

8

Wang, Steve C., and Ling Zhong. "Estimating the number of pulses in a mass extinction." Paleobiology 44, no. 2 (February 12, 2018): 199–218. http://dx.doi.org/10.1017/pab.2016.30.

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AbstractThe Signor-Lipps effect states that even a sudden mass extinction will invariably appear gradual in the fossil record, due to incomplete fossil preservation. Most previous work on the Signor–Lipps effect has focused on testing whether taxa in a mass extinction went extinct simultaneously or gradually. However, many authors have proposed scenarios in which taxa went extinct in distinct pulses. Little methodology has been developed for quantifying characteristics of such pulsed extinction events. Here we introduce a method for estimating the number of pulses in a mass extinction, based on the positions of fossil occurrences in a stratigraphic section. Rather than using a hypothesis test and assuming simultaneous extinction as the default, we reframe the question by asking what number of pulses best explains the observed fossil record.Using a two-step algorithm, we are able to estimate not just the number of extinction pulses but also a confidence level or posterior probability for each possible number of pulses. In the first step, we find the maximum likelihood estimate for each possible number of pulses. In the second step, we calculate the Akaike information criterion and Bayesian information criterion weights for each possible number of pulses, and then apply ak-nearest neighbor classifier to these weights. This method gives us a vector of confidence levels for the number of extinction pulses—for instance, we might be 80% confident that there was a single extinction pulse, 15% confident that there were two pulses, and 5% confident that there were three pulses. Equivalently, we can state that we are 95% confident that the number of extinction pulses is one or two. Using simulation studies, we show that the method performs well in a variety of situations, although it has difficulty in the case of decreasing fossil recovery potential, and it is most effective for small numbers of pulses unless the sample size is large. We demonstrate the method using a data set of Late Cretaceous ammonites.

9

Daley, D. J., David M. Hull, and James M. Taylor. "Bisexual Galton–Watson branching processes with superadditive mating functions." Journal of Applied Probability 23, no. 3 (September 1986): 585–600. http://dx.doi.org/10.2307/3213999.

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For a bisexual Galton–Watson branching process with superadditive mating function there is a simple criterion for determining whether or not the process becomes extinct with probability 1, namely, that the asymptotic growth rate r should not exceed 1. When extinction is not certain (equivalently, r > 1), simple upper and lower bounds are established for the extinction probabilities. An example suggests that in the critical case that r = 1, some condition like superadditivity is essential for ultimate extinction to be certain. Some illustrative numerical comparisons of particular mating functions are made using a Poisson offspring distribution.

10

Daley, D. J., David M. Hull, and James M. Taylor. "Bisexual Galton–Watson branching processes with superadditive mating functions." Journal of Applied Probability 23, no. 03 (September 1986): 585–600. http://dx.doi.org/10.1017/s0021900200111763.

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For a bisexual Galton–Watson branching process with superadditive mating function there is a simple criterion for determining whether or not the process becomes extinct with probability 1, namely, that the asymptotic growth rate r should not exceed 1. When extinction is not certain (equivalently, r > 1), simple upper and lower bounds are established for the extinction probabilities. An example suggests that in the critical case that r = 1, some condition like superadditivity is essential for ultimate extinction to be certain. Some illustrative numerical comparisons of particular mating functions are made using a Poisson offspring distribution.

11

Zhdanov, Vladimir P. "Criterion for extinction of CO oxidation in a catalytic monolith." Catalysis Letters 116, no. 1-2 (April 13, 2007): 23–26. http://dx.doi.org/10.1007/s10562-007-9100-2.

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12

Dolgopyat, D., P. Hebbar, L. Koralov, and M. Perlman. "Multi-type branching processes with time-dependent branching rates." Journal of Applied Probability 55, no. 3 (September 2018): 701–27. http://dx.doi.org/10.1017/jpr.2018.46.

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Abstract Under mild nondegeneracy assumptions on branching rates in each generation, we provide a criterion for almost sure extinction of a multi-type branching process with time-dependent branching rates. We also provide a criterion for the total number of particles (conditioned on survival and divided by the expectation of the resulting random variable) to approach an exponential random variable as time goes to ∞.

13

Chichilnisky, Graciela, and Peter Eisenberger. "Asteroids: Assessing Catastrophic Risks." Journal of Probability and Statistics 2010 (2010): 1–15. http://dx.doi.org/10.1155/2010/954750.

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We evaluate two risk profiles: (i) global warming risks and (ii) collisions with asteroids that can cause the extinction of our species. The expected values computed for these two risks suggest that no action will be taken to avoid extinction. The result is somewhat counterintuitive, but it is typical of the results of using classic decision theory to evaluate catastrophic risks in the distant future, see the study by Posner (2004). We establish why expected value is insensitive to catastrophic risks see the study by Chichilnisky (1996), and use another criterion to evaluate risk based on axioms for choice under uncertainty that update the classic Von Neumann theory and require equal treatment for rare and frequent events. Optimizing according to the new criterion is shown to be equivalent to optimizing expected utility with a restriction on the worst outcome in the case of a catastrophe. The evaluation obtained from the new criterion seems more intuitively plausible, and suggests a more practical and realistic approach to catastrophic risks: optimizing expected value while minimizing losses in the case of a catastrophe.

14

Sabbar, Yassine, Mehmet Yavuz, and Fatma Özköse. "Infection Eradication Criterion in a General Epidemic Model with Logistic Growth, Quarantine Strategy, Media Intrusion, and Quadratic Perturbation." Mathematics 10, no. 22 (November 11, 2022): 4213. http://dx.doi.org/10.3390/math10224213.

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This article explores and highlights the effect of stochasticity on the extinction behavior of a disease in a general epidemic model. Specifically, we consider a sophisticated dynamical model that combines logistic growth, quarantine strategy, media intrusion, and quadratic noise. The amalgamation of all these hypotheses makes our model more practical and realistic. By adopting new analytical techniques, we provide a sharp criterion for disease eradication. The theoretical results show that the extinction criterion of our general perturbed model is mainly determined by the parameters closely related to the linear and quadratic perturbations as well as other deterministic parameters of the system. In order to clearly show the strength of our new result in a practical way, we perform numerical examples using the case of herpes simplex virus (HSV) in the USA. We conclude that a great amount of quadratic noise minimizes the period of HSV and affects its eradication time.

15

Zhang, Song, Guoqing Li, Shuguang Li, and Xintong Liu. "A Method of Demarcating Critical Failure Impedance Boundary of Multi-Infeed HVDC Systems Based on Minimum Extinction Angle." Mathematical Problems in Engineering 2021 (August 31, 2021): 1–14. http://dx.doi.org/10.1155/2021/9923737.

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A method of rapidly demarcating the critical commutation failure (CF) region of a multi-infeed high-voltage direct-current (HVDC) system is proposed. Based on the nodal impedance matrix and nodal voltage interaction factor, for different AC fault conditions—both balanced and unbalanced—a method of calculating the extinction angles of converters in multi-infeed HVDC systems is deduced in detail. First, the extinction angles of convertor stations under single-phase, double-phase, and three-phase ground faults and line-to-line faults occurring at any bus in an AC system are calculated. The minimum extinction angle serves as a CF criterion. If the calculated extinction angle for a certain bus is smaller than the minimum extinction angle, then a fault at that bus will cause CF of the HVDC system and put that bus into a failed bus set. The critical failure impedance boundaries of the topology diagram can therefore be demarcated by examining every bus in the AC system. The validity and accuracy of the proposed index and the method were verified by calculation results based on the three-infeed HVDC system model of the IEEE 39-bus system. Finally, the critical failure impedance boundary was demarcated in the IEEE 118-bus system to demonstrate the application in a wider range of systems.

16

Patra, Sudeshna, Neal J. Evans II, Kee-Tae Kim, Mark Heyer, Jens Kauffmann, Jessy Jose, Manash R. Samal, and Swagat R. Das. "Tracers of Dense Gas in the Outer Galaxy." Astronomical Journal 164, no. 4 (September 7, 2022): 129. http://dx.doi.org/10.3847/1538-3881/ac83af.

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Abstract We have mapped HCN and HCO+ (J = 1 → 0) line emission toward a sample of seven star-forming regions (with 12 + log [ O / H ] ranging from 8.34 to 8.69) in the outer Milky Way (Galactocentric distance >9.5 kpc), using the 14 m radio telescope of the Taeduk Radio Astronomy Observatory. We compare these two molecular lines with other conventional tracers of dense gas, millimeter-wave continuum emission from dust and extinction thresholds (A V ≥ 8 mag), inferred from the 13CO line data. HCN and HCO+ correlate better with the millimeter emission than with the extinction criterion. A significant amount of luminosity comes from regions below the extinction criterion and outside the millimeter clump for all the clouds. The average fraction of HCN luminosity from within the regions with A V ≥ 8 mag is 0.343 ± 0.225; for the regions of millimeter emission, it is 0.478 ± 0.149. Based on a comparison with column density maps from Herschel, HCN and HCO+ trace dense gas in high column density regions better than does 13CO. HCO+ is less concentrated than HCN for outer Galaxy targets, in contrast with the inner Galaxy sample, suggesting that metallicity may affect the interpretation of tracers of dense gas. The conversion factor between the dense gas mass (M dense) and line luminosities of HCN and HCO+, when integrated over the whole cloud, is comparable to factors used in extragalactic studies.

17

Saxton, M. A., J. P. Whiteley, D. Vella, and J. M. Oliver. "On thin evaporating drops: When is the -law valid?" Journal of Fluid Mechanics 792 (February 29, 2016): 134–67. http://dx.doi.org/10.1017/jfm.2016.76.

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We study the evolution of a thin, axisymmetric, partially wetting drop as it evaporates. The effects of viscous dissipation, capillarity, slip and diffusion-dominated vapour transport are taken into account. A matched asymptotic analysis in the limit of small slip is used to derive a generalization of Tanner’s law that takes account of the effect of mass transfer. We find a criterion for when the contact-set radius close to extinction evolves as the square root of the time remaining until extinction – the famous $d^{2}$-law. However, for a sufficiently large rate of evaporation, our analysis predicts that a (slightly different) ‘$d^{13/7}$-law’ is more appropriate. Our asymptotic results are validated by comparison with numerical simulations.

18

Burke, Russell L., and Stephen R. Humphrey. "Rarity as a criterion for endangerment in Florida's fauna." Oryx 21, no. 2 (April 1987): 97–102. http://dx.doi.org/10.1017/s0030605300026624.

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It has been argued that the initial rarity of an animal species may be a good indicator of subsequent vulnerability. The usefulness of this argument in the conservation of endangered species has been investigated by the authors, who have compared the apparent vulnerability of certain rare animals with their actual status. The two approaches agreed substantially, but some striking differences occurred. Some rare species seem more prone to extinction than is officially recognized, and their status should be reviewed. Other species are not particularly rare, but are threatened for other biological and economic reasons. Knowledge of rarity is a good starting point, but this sould be followed by a detailed examination of other relevant factors to discern genuine risk.

19

Rice, Jake C., and Èmilie Legacè. "When control rules collide: a comparison of fisheries management reference points and IUCN criteria for assessing risk of extinction." ICES Journal of Marine Science 64, no. 4 (March 9, 2007): 718–22. http://dx.doi.org/10.1093/icesjms/fsm011.

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Abstract Rice, J. C., and Legacè, È. 2007. When control rules collide: a comparison of fisheries management reference points and IUCN criteria for assessing risk of extinction. – ICES Journal of Marine Science, 64: 718–722. The quantitative criteria used by the International Union for the Conservation of Nature (IUCN) to assess risk-of-extinction are compared with reference points used by ICES and other fisheries organizations for advising on fisheries management. Criteria based on numbers of individuals and geographic range appear to be in harmony with limit reference points and control rules used in fisheries management, with reference points indicating that fisheries should be closed well before there is any risk of extinction. However, there is huge potential for conflict between fisheries and risk-of-extinction approaches when considering the extent of population declines. Of 89 species examined, the decline criterion suggested a serious risk-of-extinction in 87%, whereas most of the stocks were still within a zone that allowed fisheries management reference points to indicate that exploitation could continue. Much of the conflict seems rooted in different types of tolerance to risk between the two disciplines. The conservation-biology community acknowledges a high tolerance for “false alarms”, to keep the probability of a “miss” very low, whereas tolerance in fisheries management is comparable for both types of error.

20

Lecoustre, Vivien R., Paul G. Arias, Somesh P. Roy, Zhaoyu Luo, Dan C. Haworth, Hong G. Im, Tianfeng F. Lu, and Arnaud Trouvé. "Direct numerical simulations of non-premixed ethylene–air flames: Local flame extinction criterion." Combustion and Flame 161, no. 11 (November 2014): 2933–50. http://dx.doi.org/10.1016/j.combustflame.2014.05.016.

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21

Xing, Yongsheng, and Yongjin Wang. "On the Extinction of a Class of Population-Size-Dependent Bisexual Branching Processes." Journal of Applied Probability 42, no. 1 (March 2005): 175–84. http://dx.doi.org/10.1239/jap/1110381379.

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In this paper, we study a class of bisexual Galton-Watson branching processes in which the law of offspring distribution is dependent on the population size. Under a suitable condition on the offspring distribution, we prove that the limit of mean growth-rate per mating unit exists. Based on this limit, we give a criterion to identify whether the process admits ultimate extinction with probability one.

22

Xing, Yongsheng, and Yongjin Wang. "On the Extinction of a Class of Population-Size-Dependent Bisexual Branching Processes." Journal of Applied Probability 42, no. 01 (March 2005): 175–84. http://dx.doi.org/10.1017/s0021900200000140.

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In this paper, we study a class of bisexual Galton-Watson branching processes in which the law of offspring distribution is dependent on the population size. Under a suitable condition on the offspring distribution, we prove that the limit of mean growth-rate per mating unit exists. Based on this limit, we give a criterion to identify whether the process admits ultimate extinction with probability one.

23

Connolly, Sean R., and Arnold I. Miller. "Global Ordovician faunal transitions in the marine benthos: ultimate causes." Paleobiology 28, no. 1 (2002): 26–40. http://dx.doi.org/10.1666/0094-8373(2002)028<0026:goftit>2.0.co;2.

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During the Ordovician Radiation, domination of benthic marine communities shifted away from trilobites, toward articulated brachiopods, and, to a lesser degree, toward bivalves and gastropods. Here, models are formulated that mathematically represent alternative hypothesized causes of this transition. These include models in which per-genus origination or extinction probabilities were constrained to be (1) constant, (2) diversity-dependent, (3) productivity-dependent, or (4) jointly dependent on productivity and diversity. Using a method adapted from capture-mark-recapture (CMR) population studies, we estimate origination, extinction, and sampling probabilities jointly in order to avoid confounding patterns in turnover probabilities with temporal variation in the quality of the fossil record. Using Akaike's Information Criterion (AIC), we assessed the fit of the alternative causal models relative to one another, and relative to a noncausal “phenomenological” alternative that placed no constraints on the pattern of temporal variation in origination or extinction. There were differences among taxa in the relative fit of these models, suggesting that the effects of productivity and diversity varied among higher taxa. In the aggregate, however, there was strong support for diversity-dependent origination. For extinction, poor fit of the alternative causal models suggests that we lack a good explanation for extinction patterns. These analyses support the hypothesis that diversity-dependent origination, particularly in trilobites, contributed to the Ordovician faunal transitions. By contrast, the effects of increased productivity, if indeed they were large enough to influence global diversification patterns, did not proceed in the hypothesized manner.

24

Barr, W. Andrew. "Signal or noise? A null model method for evaluating the significance of turnover pulses." Paleobiology 43, no. 4 (July 31, 2017): 656–66. http://dx.doi.org/10.1017/pab.2017.21.

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AbstractPatterns of turnover in the mammalian fossil record have been interpreted as reflecting “pulses” of originations and extinctions hypothesized to be driven by climate change. However, criteria for determining what constitutes a meaningful pulse have been idiosyncratic, and investigations of turnover patterns in mammals have yielded mixed results.This study presents simple simulations of fossil records in which origination and extinction probabilities for each lineage are held constant. Nonetheless, the total number of turnover events per time bin varies stochastically, producing statistical “noise.” Various simulation and analytical assumptions are examined to determine their impact on the type I error rate (i.e., how often “pulses” are detected in a purely stochastic process).Results suggest that simple analytical parameters (length of time bins and turnover-pulse criterion) have predictable and straightforward effects on false-positive rates. Furthermore, “pulses” of turnover of a magnitude similar to that observed in the terrestrial mammalian fossil record may be quite common under realistic analytical conditions.The null turnover model offers a practical way to evaluate the significance of observed turnover events in future empirical studies of the fossil record. In evaluating the significance of a “pulse” of fossil origination or extinction events, analytical parameters can be explored using this null model to determine the approximate type I error rate for a set of parameters. Because false-positive rates are shown to be quite high, functional trait-based approaches may offer more reliable indicators of the impact of climate change on turnover dynamics.

25

Lingam, Manasvi, Claudio Grimaldi, and Amedeo Balbi. "A birth-death-migration model for life in astrophysical environments." Monthly Notices of the Royal Astronomical Society 509, no. 3 (October 28, 2021): 4365–71. http://dx.doi.org/10.1093/mnras/stab3108.

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ABSTRACT To assess the number of life-bearing worlds in astrophysical environments, it is necessary to take the intertwined processes of abiogenesis (birth), extinction (death), and transfer of life (migration) into account. We construct a mathematical model that incorporates this trio of mechanisms and accordingly derive the probability distribution function and other statistical properties (e.g. mean) for the number of worlds with biospheres. We show that a given astrophysical setting may become eventually saturated with life if the rate of successful transfers of organisms is higher than the extinction rate of biospheres. Based on the available data, we suggest that this criterion might be fulfilled for star-forming clusters (and perhaps the Galactic bulge under optimal circumstances), thereby indicating that such regions could constitute promising abodes for hosting and detecting life.

26

Hartl, A., and M. O. Wenig. "Regularisation model study for the least-squares retrieval of aerosol extinction time series from UV/VIS MAX-DOAS observations for a ground layer profile parameterisation." Atmospheric Measurement Techniques 6, no. 8 (August 12, 2013): 1959–80. http://dx.doi.org/10.5194/amt-6-1959-2013.

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Abstract. The retrieval of tropospheric aerosol extinctions from MAX-DOAS observations of O4 using a small number of three or four extinction profile parameters suitable for boundary layer reconstruction is investigated with respect to the following questions. First, to what extent does this nominally over-constrained pure least-squares problem for the inversion of the radiative transfer equation require regularisation and how should parameters of the regularisation be chosen? Second, how can a lack of information in the under-constrained case be best compensated by using the information contained in a sequence of observations and by explicitly including intensities into the fit? The forward model parameterises the optical properties of the boundary layer aerosol by its extinction profile, single-scattering albedo and a Henyey–Greenstein phase function. Forward calculations are carried out online, i.e. without look-up tables. The retrieval uses a Tikhonov regularisation combined with an approximate L-curve criterion and empirical a priori information from the retrieval sequence based on previous valid solutions. The consistency of the approach is demonstrated in selected model case studies assuming a polluted urban scenario and westward viewing direction of the instrument. It is shown that a dynamic choice of the regularisation parameter is crucial for high aerosol load and large diurnal variations. The quality of the retrieval can be improved significantly if the retrieval sequence and thus the a priori is chosen according to the information content of the measurement series. Additional intensities improve the solution for all solar angles if suitably weighted. This flexible retrieval algorithm allows for reconstruction of aerosol profiles in the boundary layer for a wide range of viewing directions and extinctions. It can thus be applied to observational geometries scanning the sky in two angular dimensions and to retrieve further aerosol optical parameters in the boundary layer.

27

Hartl, A., and M. O. Wenig. "Regularisation model study for the least squares retrieval of aerosol extinction time series from UV/VIS MAX-DOAS observations for a ground layer profile parametrisation and westward viewing direction." Atmospheric Measurement Techniques Discussions 6, no. 2 (March 14, 2013): 2583–641. http://dx.doi.org/10.5194/amtd-6-2583-2013.

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Abstract. The retrieval of tropospheric aerosol extinctions from MAX-DOAS observations of O4 using a small number of three or four extinction profile parameters suitable for boundary layer reconstruction is investigated with respect to the following questions. First, to what extent does this nominally over-constrained pure least squares problem for the inversion of the radiative transfer equation require regularisation and how should parameters of the regularisation be chosen. Second, how can a lack of information in the under-constrained case be best compensated by using the information contained in a sequence of observations and by explicitly including intensities into the fit. The forward model parametrises the optical properties of the boundary layer aerosol by its extinction profile, single scattering albedo and a Henyey–Greenstein phase function. Forward calculations are carried out online, i.e. without look-up tables. The retrieval uses a Tikhonov regularisation combined with an approximate L-curve criterion and empirical a priori information from the retrieval sequence based on previous valid solutions. The consistency of the approach is demonstrated in selected model case studies assuming a polluted urban scenario and westward viewing direction of the instrument. It is shown that a dynamic choice of the regularisation parameter is crucial for high aerosol load and large diurnal variations. The quality of the retrieval can be improved significantly, if the retrieval sequence and thus the a priori is chosen according to the information content of the measurement series. Additional intensities improve the solution for all solar angles if suitably weighted. This flexible retrieval algorithm allows reconstruction of aerosol profiles in the boundary layer for a wide range of viewing directions and extinctions. It can thus be applied to observational geometries scanning the sky in two angular dimensions and to retrieve further aerosol optical parameters in the boundary layer.

28

Djakaria, Ismail, Muhammad Bachtiar Gaib, and Resmawan Resmawan. "Analysis of The Rosenzweig-MacArthur Predator-Prey Model with Anti-Predator Behavior." CAUCHY 6, no. 4 (May 30, 2021): 260–69. http://dx.doi.org/10.18860/ca.v6i4.11472.

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This paper discusses the analysis of the Rosenzweig-MacArthur predator-prey model with anti-predator behavior. The analysis is started by determining the equilibrium points, existence, and conditions of the stability. Identifying the type of Hopf bifurcation by using the divergence criterion. It has shown that the model has three equilibrium points, i.e., the extinction of population equilibrium point (E0), the non-predatory equilibrium point (E1), and the co-existence equilibrium point (E2). The existence and stability of each equilibrium point can be shown by satisfying several conditions of parameters. The divergence criterion indicates the existence of the supercritical Hopf-bifurcation around the equilibrium point E2. Finally, our model's dynamics population is confirmed by our numerical simulations by using the 4th-order Runge-Kutta methods.

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Duarte, A., C. Laginhas, A. Lourenço, I. Simões, and P. Martins. "Is Praecox Feeling at risk of extinction?" European Psychiatry 65, S1 (June 2022): S218—S219. http://dx.doi.org/10.1192/j.eurpsy.2022.569.

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Introduction Praecox feeling (PF) is a characteristic feeling of bizarreness or unease that a psychiatrist experiences when facing a patient with schizophrenia. This term, proposed by Rumke in 1941, was considered an important feature of a schizophrenia diagnosis. However, since the movement toward operational diagnostic methods in the late 1970s, it has fallen out of use. Objectives This work aims to discuss the role of Praecox Feeling in the clinical approach to schizophrenia diagnosis. Methods PubMed database was searched using combinations of the terms “praecox”, combined with “feeling” and “schizophrenia”. Results PF is sometimes experienced silently before the patient participates verbally. An experienced and attentive clinician can intuitively feels changes in the body posture, facial expression, the tone of the voice, motor behavior, and attitude that could look insignificant, but as a whole they present the patient as “definitely un-understandable.” Although there is lacking evidence to sustain the rehabilitation of the PF as a reliable and valid clinical criterion consistent with the operational approach, a broader scientific approach is called for. PF should not be trivialized, as is sometimes the case, into a quick diagnosis but could be a real determinant of medical decision. Conclusions Even though there may not be sufficient evidence to consider it valid clinical diagnostic criteria, it still appears to play an important role in the clinical decision-making process and should not be underestimated or stigmatized. This concept is not completely subjective and does rely on objective information, such as the patient’s behaviour and body language. Disclosure No significant relationships.

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Li, Yan Hui, Shu Zhong Wang, Li Li Qian, and Sheng Wen. "An Assessment of Supercritical Hydrothermal Combustion (SCHC) for Organic Wastes Destruction." Advanced Materials Research 955-959 (June 2014): 1777–82. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.1777.

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The supercritical hydrothermal combustion (SCHC) accompanied by visible hydrothermal flame in supercritical water completely differs from conventional combustion, which represents more prominent comprehensive technical advantages in organic wastes destruction, comparing with wet-air oxidation, incineration and flameless SCWO. This paper reviews the existing SCHC reactors, which can be used for studying the ignition and extinction characteristics of various fuels, and also shows their effectiveness for the pollutant disposal and potential optimization directions. To date, the ignition and extinction temperatures of isopropyl alcohol, methanol and ethanol have been investigated broadly, however it is still necessary to further explore the ignition mechanism from micro perspective and build up proper ignition criterion models for hydrothermal flame. In addition, further research on the migration and conversion rules of various recalcitrant compounds such as phenol, ammonia, and so on during SCHC process is also of great significance.

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Hewson, John C. "An extinction criterion for nonpremixed flames subject to brief periods of high dissipation rates." Combustion and Flame 160, no. 5 (May 2013): 887–97. http://dx.doi.org/10.1016/j.combustflame.2013.01.004.

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Schueller, Amy M., and Daniel B. Hayes. "Minimum viable population size for lake sturgeon (Acipenser fulvescens) using an individual-based model of demographics and genetics." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 1 (January 2011): 62–73. http://dx.doi.org/10.1139/f10-129.

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Population viability analysis is a useful tool to explore the relationship between extinction risk and population size, but often does not include genetic factors. Our objectives were to determine minimum viable population size (MVP) for lake sturgeon ( Acipenser fulvescens ) and examine how inbreeding depression may affect MVP. Our individual-based model incorporated inbreeding depression in two ways: individuals with inbreeding coefficients above a threshold experienced inbreeding depression (threshold), and individuals experienced inbreeding depression at a rate related to their inbreeding coefficient (gradual). Three mechanisms relating inbreeding to fitness were explored (young-of-the-year (YOY) viability, post-YOY viability, number of progeny). The criterion we used to determine MVP was a 5% chance of extinction over 250 years. The estimated MVP without inbreeding effects was 80 individuals. For some scenarios incorporating inbreeding, MVP did not change, but for others, MVP was substantially higher, reaching values up to 1800. Results demonstrate that extinction risk and MVP can be influenced by both demographic stochasticity and inbreeding depression. This research should inform management by determining MVP and how inbreeding, which is expected to accrue in remnant populations because of generations of low abundance, may affect MVP.

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Althagafi, Hashem, and Sergei Petrovskii. "Metapopulation Persistence and Extinction in a Fragmented Random Habitat: A Simulation Study." Mathematics 9, no. 18 (September 8, 2021): 2202. http://dx.doi.org/10.3390/math9182202.

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Habitat fragmentation is recognized as the most serious threat to biodiversity worldwide and has been the focus of intensive research for a few decades. Due to the complexity of the problem, however, there are still many issues that remain poorly understood. In particular, it remains unclear how species extinction or persistence in a fragmented habitat consisting of sites with randomly varying properties can be affected by the strength of inter-site coupling (e.g., due to migration between sites). In this paper, we address this problem by means of numerical simulations using a conceptual single-species spatially-discrete system. We show how an increase in the inter-site coupling changes the population distribution, leading to the formation of persistence domains separated by extinction domains. Having analysed the simulation results, we suggest a simple heuristic criterion that allows one to distinguish between different spatial domains where the species either persists or goes extinct.

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McL Mathieson, A. "Concerning Single Crystal Reflectivity Curves." Australian Journal of Physics 41, no. 3 (1988): 393. http://dx.doi.org/10.1071/ph880393.

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The extinguished reflectivity curve of a Bragg single crystal reflection represents the basic experimental evidence for the determination of accurate structure factors. In normal measurement procedures of one-dimensional (ID) 'counter' profiles, information on such curves is obscured by the presence of other, more dominant components. It is therefore difficult to separate out these curves so that a realistic correction for extinction can be applied. By considering the 'shape' of a Bragg reflection in the plane of diffraction from the ~w, ~2e viewpoint, procedures have been deduced for practical zero wavelength dispersion measurement of reflectivity curves for virtually any e value and, with these curves, corrections can be applied to produce extinction-free structure factor values. Attention is drawn to the fact that the width of the experimental reflectivity curve (say at half maximum) can provide a valuable criterion to assist in attaining the 'kinematical limit'.

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Wuhaib, S. A., and N. F. Abd. "CONTROL OF PREY DISEASE IN STAGE STRUCTURE MODEL." Tikrit Journal of Pure Science 25, no. 2 (March 17, 2020): 129. http://dx.doi.org/10.25130/j.v25i2.968.

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In this paper, a mathematical model consisting of the prey-predator model, prey is at risk of disease then become as susceptible and infected, while predator with different stage structure: immature and mature predator, the infected prey is at risk recover and harvest. The function of disease is proportionality function. At the beginning, the reasons of studying stage structure and the dynamic of nontrivial subsystems that may be lead to coexistence of these types of spices explain and by using Maple software, Jacobean matrix, Routh-Hurwitz criterion, Bendixson-Dulac criterion and Lyapunov function to prove the existence, periodic solution, local and global stability. We concluded that the survival for two preys are possible through the non-periodic solution due to the Bendixson-Dulac criterion, also the immature predator neither attack preys nor yield offspring's and die when the mature predator extinction, the global stability conditions for the original system be stretch of global stability conditions for subsystems. Finally, Mathematica software employs to describe some results in numerical simulation http://dx.doi.org/10.25130/tjps.25.2020.040

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Berumen Jiménez, Mauricio, Ricardo David Valdez Cepeda, Santiago de Jesús Méndez Gallegos, Jorge Cadena Íñiguez, Alfredo Esparza Orozco, and Luis Antonio Tarango Arámbula. "DETERMINATION OF THE CONSERVATION STATUS OF THE “ESCAMOLERA” ANT (Liometopum apiculatum MAYR) IN MEXICO BY THE SPECIES RISK ASSESSEMENT METHODOLOGY – MER." Agrociencia 55, no. 6 (September 30, 2021): 539–55. http://dx.doi.org/10.47163/agrociencia.v55i6.2558.

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The larvae and pupae of Liometopum apiculatum, an ant species known as “escamolera” (Lap), are valued for their flavour and nutritional value. Currently demand at restaurants trade, high price and other factors have threatened their populations. However, in Mexico there is no risk assessment for this species. Therefore, information was compiled to evaluate the conservation status of L apiculatum. The species Risk Assessment Methodology (MER) of Appendix I in the Mexican Standard NOM-059-SEMARNAT-2010 determines the risk category of a species based on scores of four criteria and places a species as “Extinct in the wild, subject to special protection, threatened or in danger of extinction”. In this study, the related scores were, for Criterion A (taxon distributional area), 3 points (restricted distribution); Criterion B (habitat status regarding its natural development), 1 point (apt, or not limiting); Criterion C (biological vulnerability), 1 point (low vulnerability); and criterion D (impact of human activity on the taxon) scored 3 points (medium impact). The sum of the scores of the four MER criteria indicated that Lap (the escamolera ant) should be placed in the category of Subject to special protection (SSP). This information shall be used to design management and conservation policies for edible insects in Mexico.

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Douin, Joël, Patrick Veyssière, and Georges Saada. "Comparison between simulated weak-beam images: Application to the extinction criterion in elastically anisotropic crystals." Philosophical Magazine A 77, no. 5 (May 1998): 1323–40. http://dx.doi.org/10.1080/01418619808214255.

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Douin Patrick Veyssiere Georges Saa, Joel. "Comparison between simulated weak-beam images: application to the extinction criterion in elastically anisotropic crystals." Philosophical Magazine A 77, no. 5 (May 1, 1998): 1323–40. http://dx.doi.org/10.1080/014186198254038.

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González, M., R. Martínez, and M. Slavtchova-Bojkova. "Stochastic Monotonicity and Continuity Properties of the Extinction Time of Bellman-Harris Branching Processes: An Application to Epidemic Modelling." Journal of Applied Probability 47, no. 1 (March 2010): 58–71. http://dx.doi.org/10.1239/jap/1269610816.

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The aim of this paper is to study the stochastic monotonicity and continuity properties of the extinction time of Bellman-Harris branching processes depending on their reproduction laws. Moreover, we show their applications in an epidemiological context, obtaining an optimal criterion to establish the proportion of susceptible individuals in a given population that must be vaccinated in order to eliminate an infectious disease. First the spread of infection is modelled by a Bellman-Harris branching process. Finally, we provide a simulation-based method to determine the optimal vaccination policies.

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González, M., R. Martínez, and M. Slavtchova-Bojkova. "Stochastic Monotonicity and Continuity Properties of the Extinction Time of Bellman-Harris Branching Processes: An Application to Epidemic Modelling." Journal of Applied Probability 47, no. 01 (March 2010): 58–71. http://dx.doi.org/10.1017/s0021900200006392.

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The aim of this paper is to study the stochastic monotonicity and continuity properties of the extinction time of Bellman-Harris branching processes depending on their reproduction laws. Moreover, we show their applications in an epidemiological context, obtaining an optimal criterion to establish the proportion of susceptible individuals in a given population that must be vaccinated in order to eliminate an infectious disease. First the spread of infection is modelled by a Bellman-Harris branching process. Finally, we provide a simulation-based method to determine the optimal vaccination policies.

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Najmiddinov, Аsilbek, Rustam Gulomov, Avazbek Batoshov, Hushbaht Hoshimov, Akhror Rakhmatov, and Sayyora Mullajonova. "conservation status of euphorbia L. in the fergana valley of central Asia." International journal of life sciences & earth sciences 6, no. 1 (March 10, 2023): 19–29. http://dx.doi.org/10.21744/ijle.v6n1.2091.

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In this article, the Euphorbia L category, species, and distribution levels located in the Fergana Valley Natural Area are listed based on the International Red Book categories. Based on the IUCN categories, 24 species were evaluated. In the study of Central Asian herbarium funds, samples are taken, and virtual herbarium funds and targeted Field Research were used. Distribution is a narrow circle of euphorbia mucronate Prok at risk of extinction, category (EN) corresponded to criterion B, and based on the data, the types of synopsis GeoCAT maps were brought.

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Firdaus, Winci. "TEKANAN KEPUNAHAN BAHASA SUWAWA: ANALISIS TINGKAT DAYA HIDUP BAHASA (THE PRESSURE OF EXTINCTION OF SUWAWA LANGUAGE: LANGUAGE LIFE-FORCE ANALYSIS)." Metalingua: Jurnal Penelitian Bahasa 16, no. 2 (January 27, 2019): 307. http://dx.doi.org/10.26499/metalingua.v16i2.240.

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This study aims to determine the characteristics of respondents and Suwawa language vitality criterion based on the average value of the index with the characteristics of respondents. With reference to the purpose, this research is useful to serve as a source of information about the life-force of Suwawa language and can also be used as a material mapping the vitality of regional languages. The research method used is descriptive quantitative method. The measuring instrument used to analyze the Suwawa language vitality criterion is Likert scale model and index with compare mean test using SPSS 23 application. Analysis of the identification of Suwawa's vitality criteria can be determined by subindex group calculation with four respondent character variables, ie sex, group age, education level. Based on the results of data analysis Suwawa's vitality criteria are classified as Stable and steady, but are threatened with extinction.

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Du, Yongcheng, and Boyun Liu. "A new criterion for evaluating the extinction abilities of moving droplets: Applied for radiative thermal shielding." AIP Advances 11, no. 9 (September 1, 2021): 095213. http://dx.doi.org/10.1063/5.0053274.

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Alroy, John. "New methods for quantifying macroevolutionary patterns and processes." Paleobiology 26, no. 4 (2000): 707–33. http://dx.doi.org/10.1666/0094-8373(2000)026<0707:nmfqmp>2.0.co;2.

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This paper documents a series of methodological innovations that are relevant to macroevolutionary studies. The new methods are applied to updated faunal and body mass data sets for North American fossil mammals, documenting several key trends across the late Cretaceous and Cenozoic. The methods are (1) A maximum likelihood formulation of appearance event ordination. The reformulated criterion involves generating a maximally likely hypothesized relative ordering of first and last appearances (i.e., an age range chart). The criterion takes faunal occurrences, stratigraphic relationships, and the sampling probability of individual genera and species into account. (2) A nonparametric temporal interpolation method called “shrink-wrapping” that makes it possible to employ the greatest possible number of tie points without violating monotonicity or allowing abrupt changes in slopes. The new calibration method is used in computing provisional definitions of boundaries among North American land mammal ages. (3) Additional methods for randomized subsampling of faunal lists, one weighting the number of lists that have been drawn by the sum of the square of the number of occurrences in each list, and one further modifying this approach to account for long-term changes in average local species richness. (4) Foote's new equations for instantaneous speciation and extinction rates. The equations are rederived and used to generate time series, confirm that logistic dynamics result from the diversity dependence of speciation but not extinction, and define the median duration of species (i.e., 2.6 m.y. for Eocene-Pleistocene mammals). (5) A method employing the G likelihood ratio statistic that is used to quantify the volatility of changes in the relative proportion of species falling in each of several major taxonomic groups. (6) Univariate measures of body mass distributions based on ordinary moment statistics (mean, standard deviation, skewness, kurtosis). These measures are favored over the method of cenogram analysis. Data are presented showing that even diverse individual fossil collections merely yield a noisy version of the same pattern seen in the overall continental data set. Peaks in speciation rates, extinction rates, proportional volatility, and shifts in body mass distributions occur at different times, suggesting that environmental perturbations do not have simple effects on the biota.

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Zhang, Ya-Jie, Huzaifa Jamil, Yan-Ju Wei, and Ya-Jing Yang. "Displacement and Extinction of Jet Diffusion Flame Exposed to Speaker-Generated Traveling Sound Waves." Applied Sciences 12, no. 24 (December 17, 2022): 12978. http://dx.doi.org/10.3390/app122412978.

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Acoustic flame suppression is a potential technology which does away with the need to carry fire-extinguishing media and does not cause secondary pollution. We herein reported an experimental study on the displacement and extinction of jet diffusion flames exposed to speaker-generated traveling sound waves with a frequency of 110–150 Hz and local sound pressure of 2–16 Pa. The simultaneous movement of the flame and fuel was captured using a high-speed camera and schlieren techniques. Results showed that the flame oscillation was dominated by induced wind produced by membrane vibrations instead of sound pressure, and this induced wind’s frequency was the same as that of sound waves. Moreover, the movement of unburned fuel and flame was not synchronous, which resulted in an interrupted fuel–flame cycle. Consequently, the flame was gradually suppressed and completely extinguished after several oscillation cycles. Finally, we determined the extinction criterion that when the dimensionless gap between the flame and the unburned fuel was greater than or equal to 7, the flame would be extinguished. Results clearly revealed the mechanism of acoustic fire extinguishing, which provided reference for the feasibility of acoustic fire-extinguishing applications.

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Danišek, Martin. "“La persona umana-relazionale”: Possibile dialogo tra la triade di Jacques Lacan e l’ontologia trinitaria." AUC THEOLOGICA 11, no. 2 (June 3, 2022): 97–115. http://dx.doi.org/10.14712/23363398.2022.6.

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The present study deals with the term desire (desiderio, Wunsch) in Jacques Lacan’s psychoanalytic approach and aims to find common intersections with Klaus Hemmerle’s vision of Trinitarian ontology. For modern psychology, desire as a constitutive element of the human person is a criterion that distinguishes the human person from the animal. Extinguishing desire in the human person brings many problems in society. If a person wants to fulfill desire that has a relational character with material things, he or she becomes frustrated. Both Jacques Lacan and Klaus Hemmerle have developed the issue of the desire of the human person in their approaches and thus offer certain solutions to the problem of the extinction of desire in the human person.

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Cantó, Begoña, Carmen Coll, Maria Jesús Pagán, Joan Poveda, and Elena Sánchez. "A Mathematical Model to Control the Prevalence of a Directly and Indirectly Transmitted Disease." Mathematics 9, no. 20 (October 13, 2021): 2562. http://dx.doi.org/10.3390/math9202562.

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In this paper, a mathematical model to describe the spread of an infectious disease on a farm is developed. To analyze the evolution of the infection, the direct transmission from infected individuals and the indirect transmission from the bacteria accumulated in the enclosure are considered. A threshold value of population is obtained to assure the extinction of the disease. When this size of population is exceeded, two control procedures to apply at each time are proposed. For each of them, a maximum number of steps without control and reducing the prevalence of disease is obtained. In addition, a criterion to choose between both procedures is established. Finally, the results are numerically simulated for a hypothetical outbreak on a farm.

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Cantó, Begoña, Carmen Coll, Maria Jesús Pagán, Joan Poveda, and Elena Sánchez. "A Mathematical Model to Control the Prevalence of a Directly and Indirectly Transmitted Disease." Mathematics 9, no. 20 (October 13, 2021): 2562. http://dx.doi.org/10.3390/math9202562.

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In this paper, a mathematical model to describe the spread of an infectious disease on a farm is developed. To analyze the evolution of the infection, the direct transmission from infected individuals and the indirect transmission from the bacteria accumulated in the enclosure are considered. A threshold value of population is obtained to assure the extinction of the disease. When this size of population is exceeded, two control procedures to apply at each time are proposed. For each of them, a maximum number of steps without control and reducing the prevalence of disease is obtained. In addition, a criterion to choose between both procedures is established. Finally, the results are numerically simulated for a hypothetical outbreak on a farm.

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Lu, Chun. "Dynamical Behavior of Stochastic Markov Switching Hepatitis B Epidemic Model with Saturated Incidence Rate." Journal of Function Spaces 2022 (January 17, 2022): 1–8. http://dx.doi.org/10.1155/2022/5574983.

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The article researches a stochastic hepatitis B epidemic model with saturated incidence rate, which is perturbed by both white noise and colored noise. Firstly, we obtain a significant criterion R 0 S which relies on environmental noises. By means of Lyapunov function approach, we show that there is a stationary distribution if R 0 S > 1 . Its condition implies that when white noise is small, in the stochastic model, there exists a stochastic positive equilibrium state without changing the basic properties of its corresponding deterministic model. Secondly, we derive sufficient criteria for extinction of the disease. Finally, we propose a definition of the solution to an impulsive stochastic functional differential equation with Markovian switching (ISFDM).

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Manna, Debasis, Alakes Maiti, and G. P. Samanta. "Deterministic and stochastic analysis of a predator–prey model with Allee effect and herd behaviour." SIMULATION 95, no. 4 (June 21, 2018): 339–49. http://dx.doi.org/10.1177/0037549718779445.

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This paper aims to study the dynamics of a predator–prey model, where both prey and predator show herd behaviour. Due to this behaviour, predator–prey interaction occurs only at the outer edge of herds formed by the populations. Positivity and boundedness of the system are discussed. A criteria for the extinction of prey is established. A steady-state analysis has been performed. Some criteria for Hopf bifurcation are derived. The stochastic version of the model is formulated to take into account the effect of fluctuating environment. A criterion of asymptotic mean square stability of this model is derived. Numerical simulations are carried out to validate our analytical findings. Implications of our analytical and numerical findings are discussed critically.

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