A SIMPLE METHOD FOR ASSESMENT OF COLONIZATION RISK OF A LARGE FILAMENTOUS ALGAE Cladophora glomerata AT DAM DOWNSTREAM REACHES USING BED MATERIAL SIZE DISTRIBUTION DATA

2019 ◽  
Vol 75 (2) ◽  
pp. I_505-I_510
Author(s):  
Yukio MIYAGAWA ◽  
Yukio ONODA ◽  
Kazuaki OHTSUKI ◽  
Keigo NAKAMURA
Keyword(s):  
Size Distribution ◽  
Distribution Data ◽  
Filamentous Algae ◽  
Cladophora Glomerata ◽  
Simple Method ◽  
Bed Material

scholarly journals Atmospheric observations with E-band microwave links – challenges and opportunities

2020 ◽  
Author(s):  
Martin Fencl ◽  
Michal Dohnal ◽  
Pavel Valtr ◽  
Martin Grabner ◽  
Vojtěch Bareš
Keyword(s):  
Water Vapor ◽  
Size Distribution ◽  
Drop Size ◽  
Drop Size Distribution ◽  
Distribution Data ◽  
Vapor Sensing ◽  
Challenges And Opportunities ◽  
Atmospheric Observations ◽  
Order Of Magnitude ◽  
Microwave Link

Abstract. Opportunistic sensing of rainfall and water vapor using commercial microwave links operated within cellular networks was conceived more than a decade ago. It has since been further investigated in numerous studies predominantly concentrating on the frequency region of 15–40 GHz. This manuscript provides the first evaluation of rainfall and water vapor sensing with microwave links operating at an E band (specifically, 71–76 GHz and 81–86 GHz), which are increasingly updating, and frequently replacing, older communication infrastructure. Attenuation-rainfall relations are investigated theoretically on drop size distribution data. Furthermore, quantitative rainfall estimates from six microwave links, operated within cellular backhaul, are compared with observed rainfall intensities. Finally, the capability to detect water vapor is demonstrated on the longest microwave link measuring 4.86 km in path length. The results show that E-band microwave links are by one order of magnitude more sensitive to rainfall than devices operating in the 15–40 GHz range and are thus able to observe even light rainfalls, a feat practically impossible to achieve previously. The E-band links are, however, substantially more affected by errors related to variable drop size distribution. Water vapor retrieval might be possible from long E band microwave links, nevertheless, the efficient separation of gaseous attenuation from other signal losses will be challenging in practice.

scholarly journals Pore system changes of damaged Brazilian oxisols and nitosols induced by wet-dry cycles as seen in 2-D micromorphologic image analysis

2009 ◽  
Vol 81 (1) ◽  
pp. 151-161 ◽  
Author(s):  
Luiz F. Pires ◽  
Klaus Reichardt ◽  
Miguel Cooper ◽  
Fabio A.M. Cássaro ◽  
Nivea M.P. Dias ◽  
...  
Keyword(s):  
Image Analysis ◽  
Size Distribution ◽  
Soil Structure ◽  
Tropical Soils ◽  
Transport Processes ◽  
Structure Characterization ◽  
Control Treatment ◽  
Simple Method ◽  
Wetting And Drying ◽  
Essential Information

Soil pore structure characterization using 2-D image analysis constitutes a simple method to obtain essential information related to soil porosity and pore size distribution (PSD). Such information is important to infer on soil quality, which is related to soil structure and transport processes inside the soil. Most of the time soils are submitted to wetting and drying cycles (W-D), which can cause important changes in soils with damaged structures. This report uses 2-D image analysis to evaluate possible modifications induced by W-D cycles on the structure of damaged soil samples. Samples of three tropical soils (Geric Ferralsol, GF; Eutric Nitosol, EN; and Rhodic Ferralsol, RF) were submitted to three treatments: 0WD, the control treatment in which samples were not submitted to any W-D cycle; 3WD and 9WD with samples submitted to 3 and 9 consecutive W-D cycles, respectively. It was observed that W-D cycles produced significant changes in large irregular pores of the GF and RF soils, and in rounded pores of the EN soil. Nevertheless, important changes in smaller pores (35, 75, and 150 µm) were also observed for all soils. As an overall consideration, it can be said that the use of image analysis helped to explain important changes in soil pore systems (shape, number, and size distribution) as consequence of W-D cycles.

scholarly journals Evolution of Soot Particle Number, Mass and Size Distribution along the Exhaust Line of a Heavy-Duty Engine Fueled with Compressed Natural Gas

Energies ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3993
Author(s):  
Elia Distaso ◽  
Riccardo Amirante ◽  
Giuseppe Calò ◽  
Pietro De Palma ◽  
Paolo Tamburrano
Keyword(s):  
Particle Size ◽  
Natural Gas ◽  
Size Distribution ◽  
Soot Formation ◽  
Distribution Data ◽  
Exhaust Pipe ◽  
Heavy Duty ◽  
Compressed Natural Gas ◽  
Soot Particles ◽  
Exhaust Line

An experimental study has been conducted to provide a characterization of the transformations that particle size distributions and the number density of soot particles can encounter along the exhaust line of a modern EURO VI compliant heavy-duty engine, fueled with compressed natural gas. Being aware of the particles history in the exhausts can be of utmost importance to understand soot formation and oxidation dynamics, so that, new strategies for further reducing these emissions can be formulated and present and future regulations met. To this purpose, particle samples were collected from several points along the exhaust pipe, namely upstream and downstream of each device the exhaust gases interact with. The engine was turbocharged and equipped with a two-stage after-treatment system. The measurements were carried out in steady conditions while the engine operated in stoichiometric conditions. Particle emissions were measured using a fast-response particle size spectrometer (DMS500) so that size information was analyzed in the range between 5 and 1000 nm. Particle mass information was derived from size distribution data using a correlation available in the literature. The reported results provide more insight on the particle emission process related to natural gas engines and, in particular, point out the effects that the turbine and the after-treatment devices produce on soot particles. Furthermore, the reported observations suggest that soot particles might not derive only from the fuel, namely, external sources, such as lubricant oil, might have a relevant role in soot formation.

The Distribution of Collisions in Japan and Methods of Estimating Collision Damage

1973 ◽  
Vol 26 (1) ◽  
pp. 108-113 ◽  
Author(s):  
Yahei Fujii ◽  
Hiroyuki Yamanouchi
Keyword(s):  
Size Distribution ◽  
Traffic Engineering ◽  
Approximate Formula ◽  
Traffic Patterns ◽  
Simple Method ◽  
Average Speed ◽  
Marine Traffic ◽  
Probability Of Collision

The estimation of collision danger is often required by harbour authorities and others for planning fairways or for increasing the safety of navigation. Fujii1 gives an approximate formula for the probability of collision in a waterway where the density of traffic, the size distribution of ships and the average speed are known. Fujii's formula is however only applicable where the traffic has been surveyed and traffic patterns are well known. Some simple method is required for estimating collision danger, especially for harbours where traffic patterns are complicated and the information available on marine traffic engineering is comparatively small.

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