The minimum area of a surface with prescribed boundary contour in a pseudoeuclidean space

1990 ◽  
Vol 51 (5) ◽  
pp. 2509-2512
Author(s):  
V. P. Gorokh
Keyword(s):  
Boundary Contour ◽  
Minimum Area

Forest management strategies for dealing with fire-related uncertainty when managing two forest seral stages

2011 ◽  
Vol 41 (2) ◽  
pp. 309-320 ◽  
Author(s):  
David W. Savage ◽  
David L. Martell ◽  
B. Mike Wotton
Keyword(s):  
Forest Management ◽  
Simulation Model ◽  
Sustainable Forest Management ◽  
Management Strategies ◽  
Fire Regimes ◽  
Analysis Tool ◽  
Planning Model ◽  
Minimum Area ◽  
Forest Management Planning ◽  
Planning Models

Ecological values are an important aspect of sustainable forest management, but little attention has been paid to maintaining these values when using traditional linear programming (LP) forest management planning models in uncertain planning environments. We embedded an LP planning model that specifies when and how much to harvest in a simulation model of a “managed” flammable forest landscape. The simulation model was used to evaluate two strategies for dealing with fire-related uncertainty when managing mature and old forest areas. The two seral stage areas were constrained in the LP planning model to a minimum of 10% of the total forest area and the strategies were evaluated under four representative fire regimes. We also developed a risk analysis tool that can be used by forest managers that wish to incorporate fire-related uncertainty in their decision-making. We found that use of the LP model would reduce the areas of the mature and old forest to their lower bound and fire would further reduce the seral areas below those levels, particularly when the mean annual burn fraction exceeds 0.45% per annum. Increasing the minimum area required (i.e., the right-hand side of the constraint) would increase the likelihood of satisfying the minimum area requirements.

Heat Exchanger Design Targets for Minimum Area and Cost

2000 ◽  
Vol 78 (2) ◽  
pp. 161-167 ◽  
Author(s):  
K. Muralikrishna ◽  
U.V. Shenoy
Keyword(s):  
Heat Exchanger ◽  
Minimum Area ◽  
Heat Exchanger Design

The Boundary Contour Method for Three-Dimensional Linear Elasticity

1996 ◽  
Vol 63 (2) ◽  
pp. 278-286 ◽  
Author(s):  
A. Nagarajan ◽  
S. Mukherjee ◽  
E. Lutz
Keyword(s):  
Boundary Element Method ◽  
Boundary Element ◽  
Linear Elasticity ◽  
Three Dimensional ◽  
Contour Method ◽  
Boundary Contour ◽  
Boundary Contour Method ◽  
Novel Variant ◽  
Elasticity Problems ◽  
Element Method

This paper presents a novel variant of the boundary element method, here called the boundary contour method, applied to three-dimensional problems of linear elasticity. In this work, the surface integrals on boundary elements of the usual boundary element method are transformed, through an application of Stokes’ theorem, into line integrals on the bounding contours of these elements. Thus, in this formulation, only line integrals have to be numerically evaluated for three-dimensional elasticity problems—even for curved surface elements of arbitrary shape. Numerical results are presented for some three-dimensional problems, and these are compared against analytical solutions.

scholarly journals Analyzing the Performance of GPS Data for Earthquake Prediction

2021 ◽  
Vol 13 (9) ◽  
pp. 1842
Author(s):  
Valeri Gitis ◽  
Alexander Derendyaev ◽  
Konstantin Petrov
Keyword(s):  
Earthquake Prediction ◽  
Spatial Density ◽  
Gps Data ◽  
Quality Of Data ◽  
Minimum Area ◽  
Seismological Data ◽  
Successful Prediction ◽  
Spatio Temporal ◽  
Hypocenter Depth

The results of earthquake prediction largely depend on the quality of data and the methods of their joint processing. At present, for a number of regions, it is possible, in addition to data from earthquake catalogs, to use space geodesy data obtained with the help of GPS. The purpose of our study is to evaluate the efficiency of using the time series of displacements of the Earth’s surface according to GPS data for the systematic prediction of earthquakes. The criterion of efficiency is the probability of successful prediction of an earthquake with a limited size of the alarm zone. We use a machine learning method, namely the method of the minimum area of alarm, to predict earthquakes with a magnitude greater than 6.0 and a hypocenter depth of up to 60 km, which occurred from 2016 to 2020 in Japan, and earthquakes with a magnitude greater than 5.5. and a hypocenter depth of up to 60 km, which happened from 2013 to 2020 in California. For each region, we compare the following results: random forecast of earthquakes, forecast obtained with the field of spatial density of earthquake epicenters, forecast obtained with spatio-temporal fields based on GPS data, based on seismological data, and based on combined GPS data and seismological data. The results confirm the effectiveness of using GPS data for the systematic prediction of earthquakes.

Mangroves of Maharashtra State (India): Diversity and Sustainability

2021 ◽  
Vol 4 (3) ◽  
pp. 178-207
Author(s):  
Narendra Kulkarni ◽  
Leela J. Bhosale
Keyword(s):  
Arabian Sea ◽  
Floristic Composition ◽  
Scylla Serrata ◽  
Human Pressure ◽  
Zonation Pattern ◽  
Minimum Area ◽  
Human Disturbances ◽  
Border Line ◽  
The Common ◽  
Uca Lactea

Mangroves are defined as tropical and sub-tropical forests with a diverse floristic composition bordering the sea on muddy or peaty low lands periodically submerged or influenced by the tides. Maharashtra is one of the coastal states of India, with many rivers emerging from Sahyadri ranges and meeting the Arabian Sea. The coast line available for Maharashtra state is 720 km. Ratnagiri, Sindhudurg, Raigad, Thane and Mumbai are the five coastal districts of the state of Maharashtra. All the districts together have more than 55 small, medium and large estuaries. It is found that estuaries like Vijaydurg shows maximum mangrove area of  and estuaries like  Kelye shows minimum area. It also reveals that the species like E. agallocha, A. ilicifolius, R. mucronata, A. officinalis and A. marina show maximum percentage of occurrence as compared to the species like X. granatum, C. iripa, B. cylindrica, S. caseolaris, H.fomes and T. gallica. The studies on mangrove biodiversity in five districts show the major variations. The study found 20 typical mangroves, 10 halophytic species, 13 border line mangroves and 15 mangrove associates from all these districts. Among these the uncommon and threatened greet pied Hornbill (Buceros bicornis) have been found at some sites. Some of the common crab species are Uca roseus, Uca lactea annulipes and Uca vocans. The species like Scylla serrata and Portunus pelagius are edible. In the present study 13 sp. of Molluscs, 25 species of edible fish, 9 species of Reptilia, 45 sp. of birds and 10 species of Mammalia are found.  It is found that out of twenty-four species analyzed, some species are analyzed as Critically Endangered (CR), some are found Endangered (EN). From this study it is found that all sites being under human pressure the natural zonation pattern is not seen. The existing zonation pattern is a result of natural distribution and human disturbances.

scholarly journals Improved operator agreement and efficiency using the minimum area contour change method for delineation of hyperintense multiple sclerosis lesions on FLAIR MRI

2013 ◽  
Vol 13 (1) ◽  
Author(s):  
David S Wack ◽  
Michael G Dwyer ◽  
Niels Bergsland ◽  
Deepa Ramasamy ◽  
Carol Di Perri ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Minimum Area ◽  
Contour Change

scholarly journals The history and characteristics of the 1980–2005 Portuguese rural fire database

2011 ◽  
Vol 11 (12) ◽  
pp. 3343-3358 ◽  
Author(s):  
M. G. Pereira ◽  
B. D. Malamud ◽  
R. M. Trigo ◽  
P. I. Alves
Keyword(s):  
Urban Areas ◽  
Unit Area ◽  
Fire Regime ◽  
Minimum Area ◽  
Burnt Area ◽  
Forested Areas ◽  
Large Fires ◽  
Burnt Areas

Abstract. We focus here on a mainland Continental Portuguese Rural Fire Database (PRFD) that includes 450 000 fires, the largest such database in Europe in terms of total number of recorded fires in the 1980–2005 period. In this work, we (a) list the most important factors for triggering and controlling the fire regime in mainland Continental Portugal, (b) describe the dataset's production, (c) discuss procedures adopted to identify and correct different fire data inconsistencies, creating a modified PRFD which we use here and make available as Supplement, (d) explore some basic temporal and completeness properties of the data. We find that the dataset's minimum measured burnt areas have changed with time between AF = 0.1 ha (1980–1990), AF = 0.01 ha (1991–1992), and AF = 0.001 ha (1992–2005), with varying degrees of completeness down to these values. These changes in minimum area measured are responsible for greater numbers of fires being recorded. A relatively small number of large fires in the PRFD are responsible for the majority of the burnt area. For example, fires with AF > 100 ha represent about 1% of all fire records but 75% of total burnt area. Finally, we consider for each Continental Portugal district and for the 26-yr period, the total number of rural fires and area burnt in forests and shrublands, each normalized by district areas. We find that the highest numbers of fires per unit area are in highly populated districts, and that the largest fraction of burnt area is in forested areas, coinciding with large parcels of continuous forests (predominantly rural and moderately urban areas).

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