Certain data on the scattering indicatrix of the ground layer of the atmosphere in the region of large angles

1984 ◽  
Vol 5 (1) ◽  
pp. 52-53 ◽  
Author(s):  
T. P. Toropova ◽  
O. D. Tokarev ◽  
A. P. Ten ◽  
M. A. Derbisalin
2006 ◽  
Vol 7 (2) ◽  
pp. 199-209 ◽  
Author(s):  
T. Standovár ◽  
P. Ódor ◽  
R. Aszalós ◽  
L. Gálhidy

2016 ◽  
Vol 75 (17) ◽  
pp. 1527-1536
Author(s):  
G. B. Veselovska ◽  
G. I. Khlopov

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2553
Author(s):  
B. R. Sanjeeva Reddy ◽  
Naresh K. Darimireddy ◽  
Chan-Wang Park ◽  
Abdellah Chehri

In this article, a novel frequency slot-based switchable antenna fabricated on flexible and nonflexible materials is presented for suitable reconfigurable radiations of Bluetooth, WiMAX, and upper WLAN applications. Initially, the performance of this structure was simulated using a CSTTM simulator and evaluated experimentally using a nonflexible FR4 structure. The same antenna was implemented on a flexible (jean) substrate with a relative permittivity of 1.7. The proposed textile antenna prototypes were fabricated by optimal dimensions of an E-shaped slot with a variation on the shape of the ground layer, integrated using a crossed T-shaped strip with ON/OFF switchable state operations. The proposed antenna prototype is compact (20 × 20 mm2), providing switchable radiations with tri bands, has frequencies ranged at 2.36–2.5 GHz for Bluetooth, 3.51–3.79 GHz and 5.47–5.98 GHz for the distinct bands of WiMAX and WLAN, respectively, as well as part of UWB operations.


2021 ◽  
Vol 53 (1) ◽  
pp. 149-158
Author(s):  
Robert J. Smith ◽  
Sarah Jovan ◽  
Susan Will-Wolf

AbstractLichens occupy diverse substrates across tremendous ranges of environmental variation. In boreal forests, lichen communities co-occur in ‘strata’ defined by terrestrial or arboreal substrates, but these strata may or may not be interchangeable as bioindicators. Do co-occurring lichen strata have similar community structures and environmental responses? Could one stratum serve as a proxy for the other? We assessed variation in species richness and community compositions between ground-layer versus epiphyte-layer lichen strata in boreal forests and peatlands of interior Alaska. Species richness was lower and more spatially structured in the ground layer than the epiphyte layer. Richness of strata was not correlated. The most compositionally unique ground-layer communities were species-poor but contained regionally rare species not common in other plots. Variation in community compositions (ordination scores) were not congruent between strata (Procrustes congruence < 0.16 on 0–1 scale); the largest departures from congruence occurred where ground layers were species-poor. The best predictors of ground-layer community compositions were hydrological and topographic, whereas epiphytes were most associated with macroclimate and tree abundances. We conclude that lichens on different substrates ‘move in different circles’: compositional gradients did not agree and the environmental gradients most important to each lichen stratum were not the same. The conditions which strongly influence one vegetation stratum may have little bearing upon another. As global changes modify habitats, an incremental change in environment may lead community trajectories to diverge among lichen strata.


2017 ◽  
Vol 144 (2) ◽  
pp. 191-205 ◽  
Author(s):  
Marlin L. Bowles ◽  
Beth A. Lawrence ◽  
Deborah J. Antlitz

2004 ◽  
Author(s):  
Tony Travouillon ◽  
Jon S. Lawrence ◽  
Laurent Jolissaint
Keyword(s):  

2005 ◽  
Vol 83 (6) ◽  
pp. 610-620 ◽  
Author(s):  
Cara R Nelson ◽  
Charles B Halpern

Limited information exists on the effects of forest management practices on bryophytes, despite their importance to forest ecosystems. We examined short-term responses of ground-layer bryophytes to logging disturbance and creation of edges in mature Pseudotsuga forests of western Washington (USA). The abundance and richness of species were measured in four 1-ha forest aggregates (patches of intact forest) and in surrounding logged areas before and after structural retention harvests. One year after treatment, species richness, total cover, and frequency of most moss and liverwort taxa declined within harvest areas. Within forest aggregates, mosses did not show significant edge effects; however, richness and abundance of liverworts declined with proximity to the aggregate edge. Our results suggest that, over short time frames, 1-ha-sized aggregates are sufficient to maintain most common mosses through structural retention harvests but are not large enough to prevent declines or losses of liverworts. Thus, current standards for structural retention, which allow for aggregates as small as 0.2 ha, may be inadequate to retain the diversity and abundance of species found in mature, undisturbed forests.Key words: bryophyte, edge effects, forest borders, forest management, logging effects, structural retention harvest.


2010 ◽  
Author(s):  
Michael Hart ◽  
Lorenzo Busoni ◽  
Olivier Durney ◽  
Simone Esposito ◽  
Wolfgang Gässler ◽  
...  

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