scholarly journals Mass invasion of non-nativeElodea canadensisMichx. in a large, clear-water, species-rich Norwegian lake – impact on macrophyte biodiversity

2012 ◽  
Vol 48 (2) ◽  
pp. 225-240 ◽  
Author(s):  
Marit Mjelde ◽  
Paola Lombardo ◽  
Dag Berge ◽  
Stein W. Johansen
Keyword(s):  
Clear Water ◽  
Water Species ◽  
Norwegian Lake

Clear water, blue skies

1997 ◽  
Author(s):  
Todd M. Johnson ◽  
Feng Liu ◽  
Richard Newfarmer
Keyword(s):  
Clear Water

The influence of currents on circular secondary clarifier performance and design

1996 ◽  
Vol 34 (3-4) ◽  
pp. 405-412 ◽  
Author(s):  
Andrea Deininger ◽  
Frank W. Günthert ◽  
Peter A. Wilderer
Keyword(s):  
Wastewater Treatment ◽  
Density Currents ◽  
Clear Water ◽  
Performance Measurements ◽  
Design Procedures ◽  
Secondary Clarifier ◽  
Current Design ◽  
Hydraulic Load ◽  
Novel Design ◽  
Wastewater Treatment Systems

Density currents in the deeper zones of clarifiers and currents in the clear water zone have a significant influence on clarifier performance. Measurements of flow velocity profiles were conducted in full-scale horizontally flown circular secondary clarifiers. Relations between the hydraulic load and the development of density currents could be detected. Those patterns are not taken into account in current design procedures. Stationary design approaches are mainly based on the overflow rate. Novel design methods based on the dynamic behavior of flow and density distribution in clarifiers are needed in order to improve the efficacy of wastewater treatment systems.

scholarly journals Salinity effects on cultured Neogloboquadrina pachyderma (sinistral) from high latitudes: new paleoenvironmental insights

2021 ◽  
Vol 41 (1) ◽  
Author(s):  
Jacqueline Bertlich ◽  
Nikolaus Gussone ◽  
Jasper Berndt ◽  
Heinrich F. Arlinghaus ◽  
Gerhard S. Dieckmann
Keyword(s):  
Sea Ice ◽  
Cold Water ◽  
Weddell Sea ◽  
Wall Thickening ◽  
High Latitudes ◽  
Neogloboquadrina Pachyderma ◽  
Antarctic Sea Ice ◽  
The Antarctic ◽  
Water Species ◽  
Cold Water Species

AbstractThis study presents culture experiments of the cold water species Neogloboquadrina pachyderma (sinistral) and provides new insights into the incorporation of elements in foraminiferal calcite of common and newly established proxies for paleoenvironmental applications (shell Mg/Ca, Sr/Ca and Na/Ca). Specimens were collected from sea ice during the austral winter in the Antarctic Weddell Sea and subsequently cultured at different salinities and a constant temperature. Incorporation of the fluorescent dye calcein showed new chamber formation in the culture at salinities of 30, 31, and 69. Cultured foraminifers at salinities of 46 to 83 only revealed chamber wall thickening, indicated by the fluorescence of the whole shell. Signs of reproduction and the associated gametogenic calcite were not observed in any of the culture experiments. Trace element analyses were performed using an electron microprobe, which revealed increased shell Mg/Ca, Sr/Ca, and Na/Ca values at higher salinities, with Mg/Ca showing the lowest sensitivity to salinity changes. This study enhances the knowledge about unusually high element concentrations in foraminifera shells from high latitudes. Neogloboquadrina pachyderma appears to be able to calcify in the Antarctic sea ice within brine channels, which have low temperatures and exceptionally high salinities due to ongoing sea ice formation.

scholarly journals Investigation of the Scattering Noise in Underwater Optical Wireless Communications

Sci ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 27
Author(s):  
Behnaz Majlesein ◽  
Asghar Gholami ◽  
Zabih Ghassemlooy
Keyword(s):  
Wireless Communications ◽  
Optical Wireless ◽  
Clear Water ◽  
Optical Wireless Communications ◽  
Channel Bandwidth ◽  
Phase Variations ◽  
Transmission Link ◽  
Channel Dependent ◽  
First Time ◽  
Scattering Noise

In underwater optical wireless communications (UOWC), scattering of the propagating light beam results in both intensity and phase variations, which limit the transmission link range and channel bandwidth, respectively. Scattering of photons while propagating through the channel is a random process, which results in the channel-dependent scattering noise. In this work, we introduce for the first time an analytical model for this noise and investigate its effect on the bit error rate performance of the UOWC system for three types of waters and a range of transmission link spans. We show that, for a short range of un-clear water or a longer range of clear water, the number of photons experiencing scattering is high, thus leading to the increased scattering noise. The results demonstrate that the FEC limit of 3×10−3 and considering the scattering noise, the maximum link spans are 51.5, 20, and 4.6 m for the clear, coastal, and harbor waters, respectively.

Evaluation of Selected Pier-Scour Equations Using Field Data

1996 ◽  
Vol 1523 (1) ◽  
pp. 186-195 ◽  
Author(s):  
Mark N. Landers ◽  
David S. Mueller
Keyword(s):  
Field Measurements ◽  
Bridge Piers ◽  
Critical Ratio ◽  
Scour Depth ◽  
Flow Depth ◽  
Clear Water ◽  
Pier Scour ◽  
Logarithmic Space ◽  
State Highway ◽  
Federal Highway

Field measurements of channel scour at bridges are needed to improve the understanding of scour processes and the ability to accurately predict scour depths. An extensive data base of pier-scour measurements has been developed over the last several years in cooperative studies between state highway departments, the Federal Highway Administration, and the U.S. Geological Survey. Selected scour processes and scour design equations are evaluated using 139 measurements of local scour in live-bed and clear-water conditions. Pier-scour measurements were made at 44 bridges around 90 bridge piers in 12 states. The influence of pier width on scour depth is linear in logarithmic space. The maximum observed ratio of pier width to scour depth is 2.1 for piers aligned to the flow. Flow depth and scour depth were found to have a relation that is linear in logarithmic space and that is not bounded by some critical ratio of flow depth to pier width. Comparisons of computed and observed scour depths indicate that none of the selected equations accurately estimate the depth of scour for all of the measured conditions. Some of the equations performed well as conservative design equations; however, they overpredict many observed scour depths by large amounts. Some equations fit the data well for observed scour depths less than about 3 m (9.8 ft), but significantly underpredict larger observed scour depths.

Soliton generation in clear water and in the presence of surfactants

2009 ◽  
Vol 36 (2) ◽  
pp. 160-162
Author(s):  
P. V. Mochulin ◽  
N. K. Shelkovnikov
Keyword(s):  
Clear Water ◽  
Soliton Generation

scholarly journals Jesus Christ’s Speeches in Maria Valtorta’s Mystical Writings: Setting, Topics, Duration and Deep-Language Mathematical Analysis

J ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 100-123 ◽  
Author(s):  
Emilio Matricciani ◽  
Liberato De Caro
Keyword(s):  
Mathematical Analysis ◽  
Clear Water ◽  
Language Statistics ◽  
Similarities And Differences ◽  
The Temple

We have studied Jesus Christ’s speeches contained in The Gospel as revealed to me by Maria Valtorta to assess: (i) similarities and differences of the speeches delivered to diverse audiences, through deep-language statistics; (ii) duration of the speeches delivered in different occasions; (iii) whether the setting of the speeches is realistic. Mathematically, the speeches can be divided into two sets: (a) two apparently well-planned and coordinated series of speeches delivered at “Clear Water” and at the Horns of Hattin (Sermon of the Mountain); (b) extempore speeches delivered in many localities (parables, speeches to people or to disciples, in Synagogues, at the Temple). By converting sequences of words into intervals, through a suitable reading/speaking speed, the speeches’ durations were found to be realistic. The setting of the speeches allows the assessment of the likelihood of the places and occasions for delivering them. Maria Valtorta wrote extraordinary speeches that she attributed to the alleged Jesus of Nazareth. In addition to their theological and doctrinal contents (whose study is far beyond the scope of this paper), the speeches are so realistic in whatever mathematical parameter, or setting, we study them, that she is either a great literary author, or—as she claims—an attentive “eyewitness” of what she reports.

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