scholarly journals THE EFFECT OF STORM DURATION ON RUBBLE MOUND BREAKWATER STABILITY

1968 ◽  
Vol 1 (11) ◽  
pp. 50 ◽  
Author(s):  
Juan B. Font
Keyword(s):  
Experimental Data ◽  
Double Layer ◽  
Wave Height ◽  
Periodic Waves ◽  
Destruction Process ◽  
Recurrence Period ◽  
Storm Duration ◽  
Rubble Mound ◽  
Very High ◽  
Selection Of

Experimental data are given to aid in the selection of the wave height for the design of a rubble mound breakwater as a function of the type and duration of the wave storm, and the allowed percentage of damage in the armour layers. In these experiments the model breakwater was subjected to the attack of periodic waves of height and in number according with the known statistical distribution for actual swells. — Some noteworthy differences were found In the effects of different duration storms. Observation of the destruction process of the breakwater with double layer of armour rocks, showed that the filter layers uncovering occurred always for armour damage percentages above 5$ and thus this last value is suggested as the ma_ ximum permissible in case of a storm of very high recurrence period.

scholarly journals DAMAGE FUNCTIONS FCR A RUBBLE-MOUND BREAKWATER UNDER THE EFFECT OF SWELLS

1970 ◽  
Vol 1 (12) ◽  
pp. 96 ◽  
Author(s):  
Juan B. Font
Keyword(s):  
Experimental Data ◽  
Wave Height ◽  
Damage Functions ◽  
Storm Duration ◽  
Rubble Mound ◽  
Damage Condition ◽  
Damage Criteria

In this paper experimental data are given to aid in the design of a rubble-mound breakwater The use of armor damage functions is supported rather than the use of the wave height for the no damage condition Damage curves defined experimentally are proposed, for both rocks and tetrapods, for different wave storm durations and for different placing tech niques A determinant influence of storm duration is found for advanced damage of the armor layers The experiments with different placing techniques showed that stability coefficients based upon the no damage criteria, do not give a reliable picture of the ultimace strength of a rubble-mound breakwater.

scholarly journals STABILITY OF RUBBLE MOUND BREAKWATER

1980 ◽  
Vol 1 (17) ◽  
pp. 120 ◽  
Author(s):  
J. Feuillet ◽  
M. Sabaton
Keyword(s):  
Wave Height ◽  
Breaking Waves ◽  
Random Waves ◽  
Regular Waves ◽  
T Wave ◽  
Design Wave Height ◽  
Storm Duration ◽  
Equivalent Wave ◽  
Rubble Mound ◽  
The Stability

The stability of a rubble mound breakwater section, with 3 in 2 armour slope, was tested under random waves attack. Tests analysis shows that the equivalent wave height characterizing the spectrum to be used in a stability formula elaborated with regular waves (for instance the Hudson's formula) is the upper twentieth height of the distribution for a storm duration of 6 hours. An analytical expression of the damage evolution as function of time modulates this choice according to the storm duration. The same rubble mound breakwater was also tested under the action of regular breaking waves. The damage was expressed in terms of the four following parameters : H0 : wave height T : wave period Dp : water depth at the toe of the structure Djj : breaker depth without the breakwater For a given wave height, the most important damage occur when : °b In this case the design wave height must be increased by about 30 % when using a stability formula elaborated for non breaking waves.

scholarly journals DESTRUCTION CRITERIA FOR RUBBLE-MOUND BREAKWATERS

1968 ◽  
Vol 1 (11) ◽  
pp. 49 ◽  
Author(s):  
Adelkis J. Rogan
Keyword(s):  
General Purpose ◽  
Wave Action ◽  
The Other ◽  
Periodic Waves ◽  
Cover Layer ◽  
Storm Duration ◽  
Equilibrium Profile ◽  
Rubble Mound ◽  
The One ◽  
Rubble Mound Breakwaters

The general purpose of the author's research undertaken in the "Laboratoxre National d'Hydraulique" was to study wave action on rubble-mound breakwaters with regular (periodic) waves on the one hand and irregular (random) wind generated waves on the other, and to compare the effects of these two types of waves by use of the storm duration t. With a first series of periodic waves experiments we have obtained the destruction of the breakwater's cover-layer for different storm durations t, by varying H and T. The mass of armor units remained constant. The angle of the slope, according to the seaward equilibrium profile could be considered as constant.

Der Sommer und Herbst 2003 aus phänologischer Sicht | Summer and autumn 2003 from a phenological point of view

2004 ◽  
Vol 155 (5) ◽  
pp. 142-145 ◽  
Author(s):  
Claudio Defila
Keyword(s):  
Time Series ◽  
New Record ◽  
Point Of View ◽  
Late Spring ◽  
Mean Deviation ◽  
Leaf Shedding ◽  
The Mean ◽  
Very High ◽  
Selection Of

The record-breaking heatwave of 2003 also had an impact on the vegetation in Switzerland. To examine its influences seven phenological late spring and summer phases were evaluated together with six phases in the autumn from a selection of stations. 30% of the 122 chosen phenological time series in late spring and summer phases set a new record (earliest arrival). The proportion of very early arrivals is very high and the mean deviation from the norm is between 10 and 20 days. The situation was less extreme in autumn, where 20% of the 103 time series chosen set a new record. The majority of the phenological arrivals were found in the class «normal» but the class«very early» is still well represented. The mean precocity lies between five and twenty days. As far as the leaf shedding of the beech is concerned, there was even a slight delay of around six days. The evaluation serves to show that the heatwave of 2003 strongly influenced the phenological events of summer and spring.

Investigation of Emulsion Flow in Steam-Assisted Gravity Drainage

SPE Journal ◽  
2013 ◽  
Vol 18 (03) ◽  
pp. 440-447 ◽  
Author(s):  
C.C.. C. Ezeuko ◽  
J.. Wang ◽  
I.D.. D. Gates
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Oil Recovery ◽  
Vital Role ◽  
Gravity Drainage ◽  
Steam Assisted Gravity Drainage ◽  
Emulsion Flow ◽  
Very High ◽  
Effective Representation

Summary We present a numerical simulation approach that allows incorporation of emulsion modeling into steam-assisted gravity-drainage (SAGD) simulations with commercial reservoir simulators by means of a two-stage pseudochemical reaction. Numerical simulation results show excellent agreement with experimental data for low-pressure SAGD, accounting for approximately 24% deficiency in simulated oil recovery, compared with experimental data. Incorporating viscosity alteration, multiphase effect, and enthalpy of emulsification appears sufficient for effective representation of in-situ emulsion physics during SAGD in very-high-permeability systems. We observed that multiphase effects appear to dominate the viscosity effect of emulsion flow under SAGD conditions of heavy-oil (bitumen) recovery. Results also show that in-situ emulsification may play a vital role within the reservoir during SAGD, increasing bitumen mobility and thereby decreasing cumulative steam/oil ratio (cSOR). Results from this work extend understanding of SAGD by examining its performance in the presence of in-situ emulsification and associated flow of emulsion with bitumen in porous media.

Electric condensation of divalent counterions by humic acid nanoparticles

2016 ◽  
Vol 13 (1) ◽  
pp. 76 ◽  
Author(s):  
Herman P. van Leeuwen ◽  
Raewyn M. Town
Keyword(s):  
Humic Acid ◽  
Charge Density ◽  
Double Layer ◽  
Ion Pairs ◽  
Ion Pairing ◽  
Counterion Condensation ◽  
Counterion Binding ◽  
Satisfactory Description ◽  
Poisson Boltzmann ◽  
Very High

Environmental context Humic acids are negatively charged soft nanoparticles that play a governing role in the speciation of many ionic and molecular compounds in the environment. The charge density in the humic acid nanoparticle can be very high and the binding of divalent cations such as Ca2+ appears to go far beyond traditional ion pairing or Poisson–Boltzmann electrostatics. A two-state approach, combining counterion condensation in the intraparticulate double layer and classical Donnan partitioning in the bulk of the particle, provides a satisfactory description of the physicochemical speciation. Abstract Experimental data for divalent counterion binding by soil humic acid nanoparticles are set against ion distributions as ensuing from continuous Poisson–Boltzmann electrostatics and a two-state condensation approach. The results demonstrate that Poisson–Boltzmann massively underestimates the extent of binding of Ca2+ by humic acid, and that electric condensation of these counterions within the soft nanoparticulate body must be involved. The measured stability of the Ca2+–humic acid associate is also much greater than that predicted for ion pairing between single Ca2+ ions and monovalent negative humic acid sites, which also points to extensive electrostatic cooperativity within the humic acid particle. At sufficiently high pH, the charge density inside the humic acid entity may indeed become so high that the bulk particle attains a very high and practically flat potential profile throughout. At this limit, all the intraparticulate Ca2+ is at approximately the same electrostatic potential and the status of individual ion pairs has become immaterial. A two-state model, combining counterion condensation in the charged intraparticulate part of the double layer at the particle–medium interface and Donnan partitioning in the uncharged bulk of the humic acid particle, seems to lead the way to adequate modelling of the divalent counterion binding for various particle sizes and different ionic strengths.

Motion Characteristics of Composite-Type Sea Cage under Pure Wave

2012 ◽  
Vol 490-495 ◽  
pp. 3405-3409
Author(s):  
Chun Liu Li ◽  
Yun Peng Zhao
Keyword(s):  
Experimental Data ◽  
Wave Height ◽  
Vertical Motion ◽  
Data Acquisition System ◽  
Horizontal Motion ◽  
Wave Condition ◽  
Composite Type ◽  
Motion Range ◽  
Motion Characteristics ◽  
Sea Cage

To study motion range changes with wave condition and motion relationship between cages, physical model experiments were carried out. The authors designed 2 models of composite-type sea cages. Experimental data obtained by the CCD data acquisition system. The experiment results showed that 1.in the same period, horizontal motion range,vertical motion range and inclination changes of float collar increase with wave height; 2.In the same wave height, horizontal motion range of the float collar increases with period; 3.The laws between vertical motion and period are not obvious 4.The laws between inclination changes and period are not obvious 5.Motion range of the first cage along the direction of waves is less than other cages.

PSXII-2 Identification of candidate SNPs associated with high prolificacy in Romanov sheep

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 254-255
Author(s):  
Alexey V Shakhin ◽  
Arsen V Dotsev ◽  
Tatiana E Deniskova ◽  
Gottfried Brem ◽  
Natalia A Zinovieva
Keyword(s):  
Higher Education ◽  
Genetic Basis ◽  
Reference Genome ◽  
Unique Property ◽  
Candidate Snps ◽  
Merino Sheep ◽  
Sheep Breeds ◽  
Important Trait ◽  
Very High ◽  
Selection Of

Abstract Prolificacy is a very important trait in sheep. Romanov sheep, the well-known Russian sheep breed, are characterized by very high prolificacy; however, the genetic basis of this unique property of Romanov sheep is still unknown. It was reported that Ovine BMPR1B gene, located on the OAR6, is associated with prolificacy in several sheep breeds. The aim of our study was to identify candidate SNPs within BMPR1B gene, related to prolificacy. To achieve this goal, using NGS technology, we sequenced ovine BMPR1B gene in Romanov sheep (n = 6), which are characterized by high prolificacy (about 270 lambs per 100 ewes). The sequences of BMPR1B gene of Noire du Velay, Tan, Southdown and Australian Horned Merino sheep breeds as well as Asiatic mouflon (n = 1), which are characterized by significantly lower prolificacy (from 110 to 180 lambs per 100 ewes) were derived from publicly available sources and used for comparison. FST analysis performed in PLINK 1.9 program revealed 10 SNPs with values higher than 0.8. The majority of candidate SNPs under putative selection were localized in the region from 29,382,098 to 29,430,387 on OAR6 of Ovine reference genome (Oar_v3.1 (Ensembl release 98). Thus, we can suggest, that this region of the BMPR1B gene can be considered as the putative region, associated with high prolificacy of Romanov sheep. Additional studies will be needed to confirm the effect of identified candidate SNPs on prolificacy traits. The research results will be useful for artificial selection of sheep with higher prolific capacity, including the introduction of desired alleles in sheep populations using genome editing technologies. This work was supported by the Russian Ministry of Science and Higher Education No. 0445-2019-0024 and RFBR No. 20-516-56002.

Mechanodestruction of Isoprene Rubber. Part 1. Process Kinetics

2021 ◽  
Vol 80 (3) ◽  
pp. 118-122
Author(s):  
V.P. Dorozhkin ◽  
◽  
E.G. Mokhnatkina ◽  
D.N. Zemsky ◽  
A.D. Valiev ◽  
...  
Keyword(s):  
Experimental Data ◽  
Molecular Mass ◽  
Rate Constants ◽  
Oxidative Destruction ◽  
Process Kinetics ◽  
Mass Fractions ◽  
Rubber Part ◽  
Kinetics Of ◽  
Selection Of ◽  
Isoprene Rubber

A method is proposed that allows us to obtain the values of the rate constants (CR) of the processes of mechanodestruction (mechanical cracking) of kм, oxidative destruction of kо, and recombination of kр macromolecules, as well as the mass fractions of the corresponding fractions of φм, φо, and φр,r involved in the plasticization process (P) of SKI-3 isoprene rubber. The method is based on the selection of the values of these parameters that correspond to the previously obtained experimental data, using the previously obtained recurrent equations and a specially developed program. The dependences of the CR on the time P at 30oC are obtained, which allows us to describe the kinetics of the processes accompanying P at this temperature, and the changes in molecular mass (MM) in this process. It is shown that constant values of CR are established at large times of P. Refined explanations of the nature of the kinetics of the CR change at P are proposed. The MM value of SKI-3 macromolecules that have not undergone destruction is calculated, depending on the time of plasticization.

scholarly journals Evaluation of sunflower cultivars for central Brazil

2008 ◽  
Vol 65 (2) ◽  
pp. 139-144 ◽  
Author(s):  
Willyam Stern Porto ◽  
Claudio Guilherme Portela de Carvalho ◽  
Ronald José Barth Pinto ◽  
Marcelo Fernandes de Oliveira ◽  
Ana Cláudia Barneche de Oliveira
Keyword(s):  
Experimental Data ◽  
Grain Yield ◽  
Oil Yield ◽  
Production Region ◽  
Central Brazil ◽  
Selection Of

Despite a large availability of areas suitable for sunflower cropping in Central Brazil, few adapted cultivars are available in the market. The objective of this work was to select sunflower cultivars adapted to this important production region. Experimental data from 2000 to 2004 were obtained by the National Sunflower Trials, coordinated by Embrapa Soja. The evaluated traits were grain and oil yields. Two criteria were used for selection of cultivars: i) the general mean obtained from different environments; ii) partitioning of general mean in favorable and unfavorable environments. Partitioning of the general mean allowed to detect the specific environment indicated for each cultivar. For grain yield, the cultivar Helio 251 presented general indication, Milênio and CF 17 could be indicated for favorable environments and ACA 884, ACA 885 and ACA 872 for the unfavorable ones. For oil yield, CF 13, Milênio, DK 4030, Helio 250 and ACA 872 had general indication; AG 966, GH 12, GV 26043, CF 17 and VDH 93 could be indicated for favorable environments, while VDH 488, Helio 251, ACA 884 and ACA 885 for the unfavorable conditions. In 2002, the partition of the general mean was not carried out. In this year, general mean of cultivars Exp 37, AG 962, GV 26048 and AG 967 were overweight the controls for grain yield and the cultivars AG 962, AG 967, GV 26048, AG 972, BRS 191, Guarani were overweight the controls for oil yield.

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