scholarly journals Analysis of Variation in Distance, Number, and Distribution of Spotting in Southeast Australian Wildfires

Fire ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 10 ◽  
Author(s):  
Michael A. Storey ◽  
Owen F. Price ◽  
Ross A. Bradstock ◽  
Jason J. Sharples
Keyword(s):  
Empirical Evidence ◽  
Regional Variation ◽  
Significant Variation ◽  
Fuel Type ◽  
Long Distance ◽  
Southeast Australia ◽  
Distance Distributions ◽  
Distribution Type ◽  
Analysis Of Variation ◽  
Spot Fires

Spotting during wildfires can significantly influence the way wildfires spread and reduce the chances of successful containment by fire crews. However, there is little published empirical evidence of the phenomenon. In this study, we have analysed spotting patterns observed from 251 wildfires from a database of over 8000 aerial line scan images capturing active wildfire across mainland southeast Australia between 2002 and 2018. The images were used to measure spot fire numbers, number of “long-distance” spot fires (> 500 m), and maximum spotting distance. We describe three types of spotting distance distributions, compare patterns among different regions of southeast Australia, and associate these with broad measures of rainfall, elevation, and fuel type. We found a relatively high correlation between spotting distance and numbers; however, there were also several cases of wildfires with low spot fire numbers producing very long-distance spot fires. Most long-distance spotting was associated with a “multi-modal” distribution type, where high numbers of spot fires ignite close to the source fire and isolated or small clumps of spot fires ignite at longer distances. The multi-modal distribution suggests that current models of spotting distance, which typically follow an exponential-shaped distribution, could underestimate long-distance spotting. We also found considerable regional variation in spotting phenomena that may be associated with significant variation in rainfall, topographic ruggedness, and fuel descriptors. East Victoria was the most spot-fire-prone of the regions, particularly in terms of long-distance spotting.

scholarly journals Regional variation in the distribution of property rights over land in sixteenth-century Ottoman rural Manisa

2020 ◽  
pp. 351-368
Author(s):  
Pinar Ceylan
Keyword(s):  
Sixteenth Century ◽  
Property Rights ◽  
Empirical Evidence ◽  
Agricultural Production ◽  
Regional Variation ◽  
Production Systems ◽  
Agricultural Production Systems

Concentrating on the Western Anatolian district of Manisa and employing tax surveys dating 1575, this study points to the regional variation in property rights institutions, which resulted in different inequality regimes across space. Empirical evidence suggests the existence of two agricultural production systems characterized by different property and surplus relations, in the southern and northern parts of the district in the late sixteenth century. Accordingly, inequality structures in these areas reflected region-specific patterns of property rights distribution within and across direct producers and landlords’ classes.

scholarly journals Fire Potential in the Spruce Budworm-damaged Forests of Ontario

1987 ◽  
Vol 63 (1) ◽  
pp. 8-14 ◽  
Author(s):  
B. J. Stocks
Keyword(s):  
Forest Fire ◽  
Fire Behavior ◽  
Spruce Budworm ◽  
Fire Spread ◽  
Early Years ◽  
Balsam Fir ◽  
Fuel Type ◽  
Complex Rearrangement ◽  
Fuel Accumulation ◽  
Spot Fires

An experimental burning program was carried out in Ontario between 1978 and 1982 to document quantitatively fire behavior in balsam fir killed by spruce budworm. Forest fire potential in budworm-killed balsam fir stands was shown to be significantly higher for a number of years following stand mortality. Crown breakage and windthrow, with resultant fuel complex rearrangement and increased surface fuel loads, peaked 5-8 years after mortality. Fire potential was greatest during this period, decreased gradually as balsam fir surface fuels began to decompose and understory vegetation proliferated. Fires occurring prior to "green-up" in the spring behaved explosively with continuous crowning, high spread rates, and severe problems with downwind spot fires. Summer fires in this fuel type did not spread at all in the early years following mortality; however, sufficient woody surface fuel accumulation 4-5 years after mortality permitted summer fire spread

scholarly journals Strategic Censorship in a Hybrid Authoritarian Regime? Differential Bias in Malaysia's Online and Print Media

2015 ◽  
Vol 15 (3) ◽  
pp. 455-478 ◽  
Author(s):  
Jason Abbott ◽  
John Wagner Givens
Keyword(s):  
Empirical Evidence ◽  
Significant Variation ◽  
Chinese Language ◽  
Democratic Regime ◽  
Ownership Structures ◽  
Democratic Regimes ◽  
Different Types ◽  
Two Factors ◽  
Code Bias ◽  
Insight Into

We analyze and compare three separate efforts to code bias in Malaysia's media and find strong empirical evidence of an ongoing and profound progovernment bias in coverage. We also find, however, significant variation in bias between different types of news outlets. While Malay and Anglophone sources tended to be strongly progovernment, Chinese-language and online outlets were far more impartial. We demonstrate that both the general bias and the variation in it are largely the result of two factors: (1) government censorship and (2) ownership structures that link many major outlets to the ruling coalition. These findings provide a detailed view of the struggle for media independence in a less-than-democratic regime and supply insight into media bias across both authoritarian and democratic regimes in Asia, as well as outside it.

scholarly journals The impact of new evidence on regional variation in paediatric tonsillectomy and adenoidectomy: a historical review

2020 ◽  
Vol 134 (12) ◽  
pp. 1036-1043
Author(s):  
J J C M van Munster ◽  
A H Zamanipoor Najafabadi ◽  
J W Schoones ◽  
W C Peul ◽  
W B van den Hout ◽  
...  
Keyword(s):  
Regional Variation ◽  
Significant Variation ◽  
Historical Review ◽  
Practice Variation ◽  
Tonsil Surgery ◽  
The Impact ◽  
New Evidence ◽  
Over Time

AbstractBackgroundTonsillectomy and adenoidectomy have been among the most commonly performed procedures in children for approximately 100 years. These procedures were the first for which unwarranted regional variation was discovered, in 1938. Indications for these procedures have become stricter over time, which might have reduced regional practice variation.MethodsThis paper presents a historical review on practice variation in paediatric tonsillectomy and adenoidectomy rates. Data on publication year, region, level of variation, methodology and outcomes were collected.ResultsTwenty-one articles on practice variation in paediatric tonsil surgery were included, with data from 12 different countries. Significant variation was found throughout the years, although a greater than 10-fold variation was observed only in the earliest publications.ConclusionNo evidence has yet been found that better indications for tonsillectomy and adenoidectomy have reduced practice variation. International efforts are needed to reconsider why we are still unable to tackle this variation.

scholarly journals Intervention effects in clefts: a study in quantitative computational syntax

2021 ◽  
Author(s):  
Giuseppe Samo ◽  
Paola Merlo
Keyword(s):  
Empirical Evidence ◽  
Long Distance ◽  
Intervention Theory ◽  
Intervention Effects ◽  
Quantitative Evidence ◽  
New Information ◽  
Future Theory

Clefts structures show an important asymmetry in interpretation: subject clefts can provide both corrective or new information foci, while non-subjects (objects, adjuncts) are only corrective. According to Belletti (2015), such an asymmetry arises from the fact that movement deriving subject clefts can target two focus positions, but non-subjects can target only one. In both cases a long-distance dependency is created, triggering locality effects. In this paper, we show that intervention effects causing ungrammaticality in certain configurations give rise to lower-than-expected frequencies in corresponding grammatical configurations. Based on sets of features that play a role in the syntactic computation of locality, we compare the theoretically expected and the actually observed counts of features in a corpus of thirteen syntactically annotated treebanks for three languages (English, French, Italian). We find the quantitative effects predicted by the theory of intervention locality. First, subject clefts, where no intervention is at play, are more frequent than object clefts, where intervention is at play. Secondly, object clefts are less frequent than expected in intervention configuration, while subject clefts are roughly as frequent as expected. Finally, we also find that the differential and direction of difference between expected and observed counts is directly proportional to the number of features that establish the intervention, the strength of the intervention. These results provide a three-fold contribution. First, they extend the empirical evidence in favour of the intervention theory of locality. Second, they provide theory-driven quantitative evidence, thus extending in a novel way the sources of evidence used to adjudicate theories. Finally, the paper provides a blueprint for future theory-driven quantitative investigations.

Beam Spreading of Partially Coherent Beams Propagating through Turbulence Atmospheric in Boundary Layer

2011 ◽  
Vol 317-319 ◽  
pp. 1862-1867 ◽  
Author(s):  
Ming Gao ◽  
Hong Lv
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Spectral Density Function ◽  
Coherent Beam ◽  
Long Distance ◽  
Beam Spreading ◽  
Partially Coherent ◽  
Boundary Layer Turbulence ◽  
Coherent Beams ◽  
Analysis Of Variation

The cross-spectral density function of the partially coherent beam on 1.06μm is extended based on the generalized Huygens-Fresnel principle by using the Gaussian Schell-mode(GSM) and the modified Frehlich spectrum. And on the analysis of variation of the beam spreading radius w with the initial emission radius w0, zenith angle θ and propagating distance z, the intensity distribution and beam spreading of GSM beam through atmospheric boundary layer turbulence are obtained under different distance. The results show that the beam spreading can be reduced at long distance for the suitable w0 according to the inflexion value of the curve. As well as, simulation results demonstrate that the modified Frehlich spectrum and the modified von Karman spectrum have little difference on the beam spreading for partially coherent beam propagating in atmospheric boundary layer turbulence.

Learnable vs. Unlearnable Harmony Patterns

2015 ◽  
Vol 46 (3) ◽  
pp. 425-451 ◽  
Author(s):  
Regine Lai
Keyword(s):  
Language Learning ◽  
Empirical Evidence ◽  
Artificial Language ◽  
Learning Paradigm ◽  
Long Distance ◽  
Artificial Language Learning ◽  
Computational Properties

The present study provides empirical evidence for Heinz’s (2010) Subregular Hypothesis, which predicts that some gaps found in the typology of phonotactic patterns are due to learnability—more specifically, that only phonotactic patterns with specific computational properties are humanly learnable. The study compares the learnability of two long-distance harmony patterns that differ typologically (attested vs. unattested) and computationally (Strictly Piecewise vs. Locally Testable) using the artificial-language-learning paradigm. The results reveal a general bias toward learning the attested, Strictly Piecewise pattern, exactly as the Subregular Hypothesis predicts.

scholarly journals Drivers of long-distance spotting during wildfires in south-eastern Australia

2020 ◽  
Vol 29 (6) ◽  
pp. 459 ◽  
Author(s):  
Michael A. Storey ◽  
Owen F. Price ◽  
Jason J. Sharples ◽  
Ross A. Bradstock
Keyword(s):  
Weather Conditions ◽  
Long Distance ◽  
Eastern Australia ◽  
Optical Line ◽  
Fire Area ◽  
Strong Winds ◽  
Upper Level ◽  
Behaviour Models ◽  
Steep Slopes ◽  
Spot Fires

We analysed the influence of wildfire area, topography, fuel, surface weather and upper-level weather conditions on long-distance spotting during wildfires. The analysis was based on a large dataset of 338 observations, from aircraft-acquired optical line scans, of spotting wildfires in south-east Australia between 2002 and 2018. Source fire area (a measure of fire activity) was the most important predictor of maximum spotting distance and the number of long-distance spot fires produced (i.e. >500m from a source fire). Weather (surface and upper-level), vegetation and topographic variables had important secondary effects. Spotting distance and number of long-distance spot fires increased strongly with increasing source fire area, particularly under strong winds and in areas containing dense forest and steep slopes. General vegetation descriptors better predicted spotting compared with bark hazard and presence variables, suggesting systems that measure and map bark spotting potential need improvement. The results from this study have important implications for the development of predictive spotting and wildfire behaviour models.

Social Complexity and Intraregional and Interregional Variation in Dental Modification

2017 ◽  
Author(s):  
Arion T. Mayes ◽  
Sarah B. Barber ◽  
Arthur A. Joyce
Keyword(s):  
Social Organization ◽  
Regional Variation ◽  
Social Complexity ◽  
Late Classic ◽  
Long Distance ◽  
Diachronic Change ◽  
Resource Deployment ◽  
Regional Comparisons ◽  
Distance Interaction ◽  
Over Time

This chapter considers the ways intentional dental modification intersects with other aspects of social organization between the Terminal Formative (150 BC–AD 100) and Late Classic (AD 500–800) periods. The practice is examined for diachronic change, relationship with social status, regional variation, and regional comparisons to Romero’s (1958, 1970) typology system. It is asserted that downplaying the presence of dental modification in favor of grave offerings when assessing status may result in a failure to acknowledge the significant resource deployment the practice required and its potential as a physical embodiment of inscribed status in Mesoamerica. Modification within the Lower Río Verde Valley mirrors types identified throughout Oaxaca and greater Mexico, with evidence of greater social complexity and long-distance interaction over time.

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