MATHEMATICAL MODEL OF THE OPERATING PROCESS OF THE ROTOR-THROWING MACHINE

The work describes theoretical studies of mathematical, physical and simulation models for studying ground-throwing equipment, in particular, the interaction of the rotor of the thrower with the soil. Changes and innovations carried out by the world community are developing in many directions related to the protection of forests from uncontrolled forest fires. The spread of an uncontrolled forest ground fire over a combustible biofuel occurs by running raids along the litter and along the bases of tree trunks at different speeds, and the height of the flame without taking measures will reach the top of the tree. We have proposed a version of a forest fire ground gun that performs a technological process with the rise of a soil layer above the soil surface, and then a three-stage rotor-thrower ejects the soil in a given direction. The process of throwing soil in an amount sufficient to extinguish the forest ground edge of the fire is a complex system of interaction of the working body with the medium of bulk elements. The main problem, in our opinion, is associated with the insufficient volume supplied by the existing units. On the issue of formalized modeling of soil movement during the operation of the rotor of a forest fire ground gun. With the modern development of digital technologies, the decision-making process on how to modernize technical equipment is unthinkable without designing a workflow. For the constant development of the model, formal relations should contain parameters characterizing the influence of the equipment operating conditions. Thus, the continuous computational experiment will allow not only to estimate the parameters of the working process, but also to manage the optimization of the model itself to determine the most effective values of its parameters. At the first stage of modeling, it was decided that the main parameter of the modernization efficiency would be the value of the average range of the ground flight. Formula relations for the model were obtained within the framework of the physics of the flight of a material point at an angle to the horizon with a minimum influence of the external environment (negligible air viscosity). At the first stage of modeling using spreadsheets, the dependence p (t) was estimated using spreadsheets, which showed that the pressure in the system stabilizes in fractions of a second. So, using the model relations, it is possible to determine in the result of a computational experiment the value of the average range of the ground flight

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MATHEMATICAL MODEL OF THE INTERACTION OF THE SCREW WORKING BODIES OF FOREST FIRE GROUND-THROWING MACHINES WITH THE GROUND COVER

Forestry Engineering Journal ◽

10.34220/issn.2222-7962/2021.1/15 ◽

2021 ◽

Vol 11 (1) ◽

pp. 163-171

Author(s):

Petr Popikov ◽

Anton Pozdnyakov

Keyword(s):

Mathematical Model ◽

Forest Fire ◽

Forest Fires ◽

Hydraulic Drive ◽

Ground Cover ◽

Forest Litter ◽

Working Fluid ◽

Hydraulic Motor ◽

Working Bodies ◽

Fire Ground

The paper provides an overview of research on the working processes of screw working bodies of technological machines. It is noted that at present such important issues in the theory of auger working bodies as the required number of auger turns, the required position of the auger spiral in relation to the center, etc. have not been fully resolved, since the solution of these issues can provide an increased productivity of the tool. A structural and technological scheme of a forest fire machine with multifunctional modules is proposed, which consists of auger working bodies, which can be changed modularly with a screw metal thread for a brush, depending on the area and type of soil, the rotor of the thrower, with the ability to drive the cutters-throwers and auger working bodies both from the power take-off shaft of the tractor, and using a hydraulic motor, a guide casing. A mathematical model of an auger working body with a hydraulic drive has been compiled for removing the ground cover with forest litter when extinguishing forest fires with a ground gun, so that combustible materials do not fall into the fire zone together with the soil flow from the rotor-thrower. The working process of the hydraulic drive of the auger working bodies of a forest fire ground-sweeping machine is described by a system of differential equations, including the equations of translational and rotational movements of the auger working body and the equation of the flow rate of the working fluid. The problem of optimization of kinematic and dynamic parameters of auger working bodies of forest fire ground-sweeping machine is set

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A Collaborative Region Detection and Grading Framework for Forest Fire Smoke Using Weakly Supervised Fine Segmentation and Lightweight Faster-RCNN

Forests ◽

10.3390/f12060768 ◽

2021 ◽

Vol 12 (6) ◽

pp. 768

Author(s):

Jin Pan ◽

Xiaoming Ou ◽

Liang Xu

Keyword(s):

Forest Fire ◽

Forest Fires ◽

Learning Strategy ◽

Early Stage ◽

Fire Detection ◽

Surveillance Systems ◽

Region Detection ◽

Decision Network ◽

Fire Smoke ◽

Weakly Supervised

Forest fires are serious disasters that affect countries all over the world. With the progress of image processing, numerous image-based surveillance systems for fires have been installed in forests. The rapid and accurate detection and grading of fire smoke can provide useful information, which helps humans to quickly control and reduce forest losses. Currently, convolutional neural networks (CNN) have yielded excellent performance in image recognition. Previous studies mostly paid attention to CNN-based image classification for fire detection. However, the research of CNN-based region detection and grading of fire is extremely scarce due to a challenging task which locates and segments fire regions using image-level annotations instead of inaccessible pixel-level labels. This paper presents a novel collaborative region detection and grading framework for fire smoke using a weakly supervised fine segmentation and a lightweight Faster R-CNN. The multi-task framework can simultaneously implement the early-stage alarm, region detection, classification, and grading of fire smoke. To provide an accurate segmentation on image-level, we propose the weakly supervised fine segmentation method, which consists of a segmentation network and a decision network. We aggregate image-level information, instead of expensive pixel-level labels, from all training images into the segmentation network, which simultaneously locates and segments fire smoke regions. To train the segmentation network using only image-level annotations, we propose a two-stage weakly supervised learning strategy, in which a novel weakly supervised loss is proposed to roughly detect the region of fire smoke, and a new region-refining segmentation algorithm is further used to accurately identify this region. The decision network incorporating a residual spatial attention module is utilized to predict the category of forest fire smoke. To reduce the complexity of the Faster R-CNN, we first introduced a knowledge distillation technique to compress the structure of this model. To grade forest fire smoke, we used a 3-input/1-output fuzzy system to evaluate the severity level. We evaluated the proposed approach using a developed fire smoke dataset, which included five different scenes varying by the fire smoke level. The proposed method exhibited competitive performance compared to state-of-the-art methods.

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Impact of climatic conditions on the parameters of failure flow of military vehicles

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211020228 ◽

2021 ◽

pp. 095440702110202

Author(s):

Nikolaj Dobrzinskij ◽

Algimantas Fedaravicius ◽

Kestutis Pilkauskas ◽

Egidijus Slizys

Keyword(s):

Climatic Factors ◽

Armed Forces ◽

Climatic Conditions ◽

Operating Conditions ◽

Technical Equipment ◽

Factors Affecting ◽

Military Vehicles ◽

Equipment Reliability ◽

Number Of Factors ◽

The Impact

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.

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Short-Term Effects of Fire Severity on Vegetation Based on Sentinel-2 Satellite Data

Sustainability ◽

10.3390/su13010432 ◽

2021 ◽

Vol 13 (1) ◽

pp. 432

Author(s):

Aru Han ◽

Song Qing ◽

Yongbin Bao ◽

Li Na ◽

Yuhai Bao ◽

...

Keyword(s):

Forest Fire ◽

Forest Fires ◽

Vegetation Change ◽

Fire Severity ◽

Dynamic Change ◽

Burned Area ◽

Fire Event ◽

Vegetation Dynamic ◽

Area Index ◽

Sentinel 2

An important component in improving the quality of forests is to study the interference intensity of forest fires, in order to describe the intensity of the forest fire and the vegetation recovery, and to improve the monitoring ability of the dynamic change of the forest. Using a forest fire event in Bilahe, Inner Monglia in 2017 as a case study, this study extracted the burned area based on the BAIS2 index of Sentinel-2 data for 2016–2018. The leaf area index (LAI) and fractional vegetation cover (FVC), which are more suitable for monitoring vegetation dynamic changes of a burned area, were calculated by comparing the biophysical and spectral indices. The results showed that patterns of change of LAI and FVC of various land cover types were similar post-fire. The LAI and FVC of forest and grassland were high during the pre-fire and post-fire years. During the fire year, from the fire month (May) through the next 4 months (September), the order of areas of different fire severity in terms of values of LAI and FVC was: low > moderate > high severity. During the post fire year, LAI and FVC increased rapidly in areas of different fire severity, and the ranking of areas of different fire severity in terms of values LAI and FVC was consistent with the trend observed during the pre-fire year. The results of this study can improve the understanding of the mechanisms involved in post-fire vegetation change. By using quantitative inversion, the health trajectory of the ecosystem can be rapidly determined, and therefore this method can play an irreplaceable role in the realization of sustainable development in the study area. Therefore, it is of great scientific significance to quantitatively retrieve vegetation variables by remote sensing.

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Empirical Research on Climate Warming Risks for Forest Fires: A Case Study of Grade I Forest Fire Danger Zone, Sichuan Province, China

Sustainability ◽

10.3390/su13147773 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7773

Author(s):

San Wang ◽

Hongli Li ◽

Shukui Niu

Keyword(s):

Wind Speed ◽

Forest Fire ◽

Climate Warming ◽

Forest Fires ◽

Meteorological Factors ◽

Sichuan Province ◽

Danger Zone ◽

Climatic Regions ◽

Area Burned ◽

Forest Fire Danger

The Sichuan province is a key area for forest and grassland fire prevention in China. Forest resources contribute significantly not only to the biological gene pool in the mid latitudes but also in reducing the concentration of greenhouse gases and slowing down global warming. To study and forecast forest fire change trends in a grade I forest fire danger zone in the Sichuan province under climate change, the dynamic impacts of meteorological factors on forest fires in different climatic regions were explored and a model between them was established by using an integral regression in this study. The results showed that the dominant factor behind the area burned was wind speed in three climatic regions, particularly in Ganzi and A’ba with plateau climates. In Ganzi and A’ba, precipitation was mainly responsible for controlling the number of forest fires while it was mainly affected by temperature in Panzhihua and Liangshan with semi-humid subtropical mountain climates. Moreover, the synergistic effect of temperature, precipitation and wind speed was responsible in basin mid-subtropical humid climates with Chengdu as the center and the influence of temperature was slightly higher. The differential forest fire response to meteorological factors was observed in different climatic regions but there was some regularity. The influence of monthly precipitation in the autumn on the area burned in each climatic region was more significant than in other seasons, which verified the hypothesis of a precipitation lag effect. Climate warming and the combined impact of warming effects may lead to more frequent and severe fires.

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Associations Between Ambient Particulate Air Pollution and Cognitive Function in Indonesian Children Living in Forest Fire–Prone Provinces

Asia Pacific Journal of Public Health ◽

10.1177/10105395211031735 ◽

2021 ◽

pp. 101053952110317

Author(s):

Bin Jalaludin ◽

Frances L. Garden ◽

Agata Chrzanowska ◽

Budi Haryanto ◽

Christine T. Cowie ◽

...

Keyword(s):

Air Pollution ◽

Cognitive Function ◽

Forest Fire ◽

Forest Fires ◽

Regression Models ◽

Individual Factors ◽

Aerodynamic Diameter ◽

Particulate Air Pollution ◽

Multivariable Models ◽

Particulate Matter 2.5

Smoke from forest fires can reach hazardous levels for extended periods of time. We aimed to determine if there is an association between particulate matter ≤2.5 µm in aerodynamic diameter (PM2.5) and living in a forest fire–prone province and cognitive function. We used data from the Indonesian Family and Life Survey. Cognitive function was assessed by the Ravens Colored Progressive Matrices (RCPM). We used regression models to estimate associations between PM2.5 and living in a forest fire–prone province and cognitive function. In multivariable models, we found very small positive relationships between PM2.5 levels and RCPM scores (PM2.5 level at year of survey: β = 0.1%; 95% confidence interval [CI] = 0.01% to 0.19%). There were no differences in RCPM scores for children living in forest fire–prone provinces compared with children living in non-forest fire–prone provinces (mean difference = −1.16%, 95% CI = −2.53% to 0.21%). RCPM scores were lower for children who had lived in a forest fire–prone province all their lives compared with children who lived in a non-forest fire–prone province all their life (β = −1.50%; 95% CI = −2.94% to −0.07%). Living in a forest fire–prone province for a prolonged period of time negatively affected cognitive scores after adjusting for individual factors.

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Characteristics of Korean Forest Fires and Forest Fire Policies in the Joseon Dynasty Period (1392–1910) Derived From Historical Records

Forests ◽

10.3390/f10010029 ◽

2019 ◽

Vol 10 (1) ◽

pp. 29

Author(s):

Donghyun Kim

Keyword(s):

Forest Fire ◽

Forest Fires ◽

East Coast ◽

Historical Record ◽

Capital City ◽

Fire Damage ◽

Historical Records ◽

Royal Authority ◽

Joseon Dynasty ◽

Fire Stations

This study examined the records of forest fire outbreaks and characteristics over the 518 years of the Joseon Dynasty period (1392–1910) through the analysis of major historical records of Korea. The historical books used in this study were 14 major national historical books, and include the Annals of the Joseon Dynasty (朝鮮王朝實錄), the Diaries of the Royal Secretariat (承政院日記), and the literature was examined, centering on official records of the royal palace in the Joseon Dynasty period. The contents of forest fires recorded in the historical record literature include the overviews of outbreak, forest fire types, and forest fire damage. According to the results of analysis of historical records, the largest forest fire damage was in the forest fire that occurred on the east coast in 1672, in which 65 persons died and in the forest fire that occurred in the same area in 1804, in which 61 persons died and 2600 private houses were destroyed by fire. The causes of fire outbreak were shown to be unknown causes in 42 cases, accidental fires in 10 cases, arson in 3 cases, thunder strike in 3 cases, hunting activities in 2 cases, child playing with fire in 1 case, cultivating activities in 1 case, and house fire in 1 case. Forest fire outbreaks were analyzed by region and by season and according to the results, 56% (39 cases) of the forest fires broke out on the east coast and 73% (46 cases) broke out in the spring. Forest fire policies include those for general forests, those for reserved forests, those for prohibited forests, those for capital city forests, those for royal family’s graves, royal ancestral shrine, and placenta chamber, those for hunting grounds such as martial art teaching fields, and relief policies for people in areas damaged by forest fires, forest fire policies for national defense facilities such as beacon fire stations, and burning and burning control policies for pest control. In conclusion, due to the seriousness of forest fires in the Joseon Dynasty period, the royal authority and local administrative agencies made various forest fire prevention policies, policies for stabilization of the people’s livelihood damaged due to forest fires, and methods to manage major facilities in forests.

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Comparison of the mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil with a topsoil that contains hematite, maghemite and goethite

Clay Minerals ◽

10.1180/claymin.2009.044.2.239 ◽

2009 ◽

Vol 44 (2) ◽

pp. 239-247 ◽

Cited By ~ 15

Author(s):

P. Nørnberg ◽

A. L. Vendelboe ◽

H. P. Gunnlaugsson ◽

J. P. Merrison ◽

K. Finster ◽

...

Keyword(s):

Organic Matter ◽

High Temperature ◽

Forest Fire ◽

Forest Fires ◽

Organic Matter Content ◽

Matter Content ◽

Humid Climate ◽

Fe Mineralogy ◽

Reducing Environment

AbstractA long-standing unresolved puzzle related to the Danish temperate humid climate is the presence of extended areas with large Fe contents, where goethite and ferrihydrite are present in the topsoil along with hematite and maghemite. Hematite and, particularly, maghemite would normally be interpreted as the result of high temperature as found after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this Fe mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down to 10 cm depth. This was not observed at the natural sites, which contained a mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which is in contrast to the natural sites. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to forest fire, but may instead result from long-term transformation in a reducing environment, possibly involving microbiology.

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Global warming and forest fires in Canada

The Forestry Chronicle ◽

10.5558/tfc69290-3 ◽

1993 ◽

Vol 69 (3) ◽

pp. 290-293 ◽

Cited By ~ 47

Author(s):

Brian J. Stocks

Keyword(s):

Global Warming ◽

Forest Fire ◽

Forest Fires ◽

Fire Management ◽

Warming Trend ◽

Research Activities ◽

Forest Fire Management ◽

The Future ◽

Innovative Thinking ◽

The Impact

The looming possibility of global warming raises legitimate concerns for the future of the forest resource in Canada. While evidence of a global warming trend is not conclusive at this time, governments would be wise to anticipate, and begin planning for, such an eventuality. The forest fire business is likely to be affected both early and dramatically by any trend toward warmer and drier conditions in Canada, and fire managers should be aware that the future will likely require new and innovative thinking in forest fire management. This paper summarizes research activities currently underway to assess the impact of global warming on forest fires, and speculates on future fire management problems and strategies.

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Temporal variations and change in forest fire danger in Europe for 1960–2012

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-1477-2014 ◽

2014 ◽

Vol 14 (6) ◽

pp. 1477-1490 ◽

Cited By ~ 39

Author(s):

A. Venäläinen ◽

N. Korhonen ◽

O. Hyvärinen ◽

N. Koutsias ◽

F. Xystrakis ◽

...

Keyword(s):

Forest Fire ◽

Forest Fires ◽

National Level ◽

Temporal Variations ◽

Fire Danger ◽

Fire Season ◽

Fire Weather ◽

Fire Weather Index ◽

Current Season ◽

Forest Fire Danger

Abstract. Understanding how fire weather danger indices changed in the past and how such changes affected forest fire activity is important in a changing climate. We used the Canadian Fire Weather Index (FWI), calculated from two reanalysis data sets, ERA-40 and ERA Interim, to examine the temporal variation of forest fire danger in Europe in 1960–2012. Additionally, we used national forest fire statistics from Greece, Spain and Finland to examine the relationship between fire danger and fires. There is no obvious trend in fire danger for the time period covered by ERA-40 (1960–1999), whereas for the period 1980–2012 covered by ERA Interim, the mean FWI shows an increasing trend for southern and eastern Europe which is significant at the 99% confidence level. The cross correlations calculated at the national level in Greece, Spain and Finland between total area burned and mean FWI of the current season is of the order of 0.6, demonstrating the extent to which the current fire-season weather can explain forest fires. To summarize, fire risk is multifaceted, and while climate is a major determinant, other factors can contribute to it, either positively or negatively.

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