Статті в журналах з теми "Swell coefficient"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Swell coefficient.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 статей у журналах для дослідження на тему "Swell coefficient".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Potter, Henry. "Swell and the drag coefficient." Ocean Dynamics 65, no. 3 (February 21, 2015): 375–84. http://dx.doi.org/10.1007/s10236-015-0811-4.
Повний текст джерела
2
Rindraharisaona, E. J., E. Cordier, G. Barruol, F. R. Fontaine, and M. Singh. "Assessing swells in La Réunion Island from terrestrial seismic observations, oceanographic records and offshore wave models." Geophysical Journal International 221, no. 3 (March 13, 2020): 1883–95. http://dx.doi.org/10.1093/gji/ggaa117.
Повний текст джерелаАнотація:
SUMMARY La Réunion Island in the southwest Indian Ocean is seasonally affected by austral swells among which some extreme events may have strong impacts on coastal infrastructures. The very limited number of sensors available on and around the island and in the whole SW Indian Ocean impedes any direct monitoring of the swell activity. In this study, we analyse direct observations of the ocean swell by combining terrestrial measurements of the microseismic noise with in situ oceanographic observations issued from two pressure gauges and an Acoustic Doppler Current Profiler (ADCP), together with swell numerical modelling. The reliability of the terrestrial seismic station to characterize the ocean activity in both the primary and secondary microseisms peaks (PM and SM, respectively), and also in the long period secondary microseismic peak (LPSM) for the case of La Réunion Island is presented and discussed here. By computing the hourly RMS of the PM and LP(SM) amplitudes, we establish a transfer function between the PM and (LP)SM amplitude and the maximum wave height, which appears to be valid for any PM and LPSM amplitudes >0.15 μm and >1.0 μm, respectively. The correlation coefficient between the PM amplitude and the wave height is >0.92. It suggests that the PM amplitude can be used as a robust proxy for the swell height and may help calibrating the wave heights from other independent observable. For some swell events, we observe LPSM that correlate well (>0.91) with the local wave height suggesting a generation by coastal swell reflection. From polarization and spectral analyses, directions and periods of swells are also well retrieved from seismic data. Finally, continuous measure of the SM amplitude shows that it can be used as precursor information for distant swells that may hit La Réunion Island a few days after their generation in the southern Indian Ocean.
3
Mitsoulis, Evan. "Annular Extrudate Swell of Newtonian Fluids: Effects of Compressibility and Slip at the Wall." Journal of Fluids Engineering 129, no. 11 (June 5, 2007): 1384–93. http://dx.doi.org/10.1115/1.2786491.
Повний текст джерелаАнотація:
Numerical simulations have been undertaken for the benchmark problem of annular extrudate swell present in pipe extrusion and parison formation in blow molding. The effects of weak compressibility and slip at the wall are studied through simple linear laws. The finite element method is used to provide numerical results for different inner/outer diameter ratios κ under steady-state conditions for Newtonian fluids. The present results provide the shape of the extrudate, and, in particular, the thickness and diameter swells, as a function of the dimensionless compressibility and slip coefficients, B and Bsl, respectively. The pressures from the simulations have been used to compute the excess pressure losses in the flow field (exit correction). Weak compressibility slightly affects the thickness swell (about 1% in the range of simulations 0⩽B⩽0.02) mainly by a swell reduction, while slip drastically reduces the swelling to 1–2% for obvious slip (Bsl≈1) and to 0 for perfect slip (Bsl>10). The exit correction increases with increasing compressibility levels and is highest for the tube (κ=0) and lowest for the slit (κ=1). It decreases monotonically to 0 as the dimensionless slip coefficient reaches its asymptotic limit of perfect slip. All results are ordered with the diameter ratio κ, between the limits of tube (κ=0) and slit (κ=1).
4
Wu, Lichuan, Anna Rutgersson, and Erik Nilsson. "Atmospheric Boundary Layer Turbulence Closure Scheme for Wind-Following Swell Conditions." Journal of the Atmospheric Sciences 74, no. 7 (July 1, 2017): 2363–82. http://dx.doi.org/10.1175/jas-d-16-0308.1.
Повний текст джерелаАнотація:
Abstract Over the ocean, atmospheric boundary layer turbulence can be altered by underlying waves. Under swell conditions, the impact of waves on the atmosphere is more complicated compared to that under wind-wave conditions. Based on large-eddy simulation (LES), the wind-following swell impact on the atmospheric boundary layer is investigated through three terms: swell-induced surface momentum flux, the vertical profile of swell-induced momentum flux, and the swell impact on atmospheric mixing. The swell-induced surface momentum flux displays a decreasing trend with increasing atmospheric convection. The swell-induced momentum flux decays approximately exponentially with height. Compared with atmospheric convection, the decay coefficient is more sensitive to wave age. Atmospheric mixing is enhanced under swell conditions relative to a flat stationary surface. The swell impact on the atmospheric boundary layer is incorporated into a turbulence closure parameterization through the three terms. The modified turbulence closure parameterization is introduced into a single-column atmospheric model to simulate LES cases. Adding only the swell impact on the atmospheric mixing has a limited influence on wind profiles. Adding both the impact of swell on the atmospheric mixing and the profile of swell-induced momentum flux significantly improves the agreement between the 1D atmospheric simulation results and the LES results, to some extent simulating the wave-induced low-level wind jet. It is concluded that the swell impact should be included in atmospheric numerical models.
5
Clemo, Henry F., and Clive M. Baumgarten. "Swelling-activated Gd3+-sensitive Cation Current and Cell Volume Regulation in Rabbit Ventricular Myocytes." Journal of General Physiology 110, no. 3 (September 1, 1997): 297–312. http://dx.doi.org/10.1085/jgp.110.3.297.
Повний текст джерелаАнотація:
The role of swelling-activated currents in cell volume regulation is unclear. Currents elicited by swelling rabbit ventricular myocytes in solutions with 0.6–0.9× normal osmolarity were studied using amphotericin perforated patch clamp techniques, and cell volume was examined concurrently by digital video microscopy. Graded swelling caused graded activation of an inwardly rectifying, time-independent cation current (ICir,swell) that was reversibly blocked by Gd3+, but ICir,swell was not detected in isotonic or hypertonic media. This current was not related to IK1 because it was insensitive to Ba2+. The PK/PNa ratio for ICir,swell was 5.9 ± 0.3, implying that inward current is largely Na+ under physiological conditions. Increasing bath K+ increased gCir,swell but decreased rectification. Gd3+ block was fitted with a K0.5 of 1.7 ± 0.3 μM and Hill coefficient, n, of 1.7 ± 0.4. Exposure to Gd3+ also reduced hypotonic swelling by up to ∼30%, and block of current preceded the volume change by ∼1 min. Gd3+-induced cell shrinkage was proportional to ICir,swell when ICir,swell was varied by graded swelling or Gd3+ concentration and was voltage dependent, reflecting the voltage dependence of ICir,swell. Integrating the blocked ion flux and calculating the resulting change in osmolarity suggested that ICir,swell was sufficient to explain the majority of the volume change at –80 mV. In addition, swelling activated an outwardly rectifying Cl− current, ICl,swell. This current was absent after Cl− replacement, reversed at ECl, and was blocked by 1 mM 9-anthracene carboxylic acid. Block of ICl,swell provoked a 28% increase in swelling in hypotonic media. Thus, both cation and anion swelling-activated currents modulated the volume of ventricular myocytes. Besides its effects on cell volume, ICir,swell is expected to cause diastolic depolarization. Activation of ICir,swell also is likely to affect contraction and other physiological processes in myocytes.
6
Phanikumar, B. R. "Volume change behaviour of an expansive clay blended with lime and pond ash – controlling swell." Quarterly Journal of Engineering Geology and Hydrogeology 54, no. 1 (June 18, 2020): qjegh2020–046. http://dx.doi.org/10.1144/qjegh2020-046.
Повний текст джерелаАнотація:
This paper presents the influence of lime content on free swell index (FSI) of an expansive clay powder passing through a 425 µm sieve and on some significant swell-compressibility characteristics of oven-dry, expansive clay with grains of a size <4.75 mm. One-dimensional swell-consolidation tests were conducted on the expansive clay passing through a 4.75 mm sieve to which lime powder (CaOH2) was added at 0, 1, 2 and 4% by dry weight of the clay. Swell potential, swelling pressure, coefficient of compressibility (av), compression index (Cc) and linear shrinkage (LS) were evaluated. While av, Cc and LS decreased significantly with increasing lime content, swelling pressure increased. Heave and swell potential also decreased with increasing lime content but only up to 2% and were found to have increased at 4% lime content. The paper also compares the swell-compressibility behaviour of 2% lime-blended expansive clay lumps and powders. Heave and swell potential were higher for clay powder than for clay lumps at 2% lime. However, swelling pressure (ps) was found to be more for clay lumps than clay powder. Furthermore, the paper also presents the variation of FSI and swell-compressibility characteristics of another expansive clay powder (of different properties) blended with pond ash contents of 0, 5, 10, 15 and 20%. One-dimensional swell-consolidation tests were conducted on clay–pond ash blends in an oedometer. Swell potential and swelling pressure decreased up to 15% of pond ash content and increased thereafter, when pond ash content was increased to 20%. FSI of the ash-blended clay specimens was also determined. FSI continuously decreased with increase in pond ash content.
7
Chernukha, Anton, Andrii Chernukha, Pavlo Kovalov, and Alexander Savchenko. "Thermodynamic Study of Fire-Protective Material." Materials Science Forum 1038 (July 13, 2021): 486–91. http://dx.doi.org/10.4028/www.scientific.net/msf.1038.486.
Повний текст джерелаАнотація:
The paper considers the material for the protective coating of building structures made of wood. The possibility of chemical processes occurring in the material leading to its expansion has been studied. The coefficient of expansion of the material when heated is practically established. It has been established that the material can swell, both under the influence of flame and when the temperature rises at a low speed. Swelling coefficient at the same time it reaches 8. The temperature range of swelling is 150–250 С, which is confirmed by thermodynamic calculations and experimentally. The temperature at which the material begins to swell is lower than the temperature of thermal destruction of wood.
8
Erzin, Yusuf. "Artificial neural networks approach for swell pressure versus soil suction behaviour." Canadian Geotechnical Journal 44, no. 10 (October 2007): 1215–23. http://dx.doi.org/10.1139/t07-052.
Повний текст джерелаАнотація:
In this study, the swell pressure versus soil suction behaviour was investigated using artificial neural networks (ANNs). To achieve this, the results of the total suction measurements using thermocouple psychrometer technique and constant-volume swell tests in oedometers performed on statically compacted specimens of Bentonite–Kaolinite clay mixtures with varying soil properties were used. Two different ANN models have been developed to predict the total suction and swell pressure. The ANNs results were compared with the experimental values and found close to the experimental results. Moreover, several performance indices such as correlation coefficient, variance account for (VAF), and root mean square error (RMSE) were calculated to check the prediction capacity of the ANN models developed. Both ANN models have shown a high prediction performance based on the performance indices. Therefore, it can be concluded that the initial soil suction is the most relevant state of suction that characterizes the potential swell pressures.
9
Wang, Yingchao, Hongwen Jing, Lijun Han, Liyuan Yu, and Qiang Zhang. "Risk analysis on swell–shrink capacity of expansive soils with efficacy coefficient method and entropy coefficient method." Applied Clay Science 99 (September 2014): 275–81. http://dx.doi.org/10.1016/j.clay.2014.07.005.
Повний текст джерела
10
Lucian, Charles, Staffan Hintze, and Joseph J. Msambichaka. "A geotechnical Study on the Characteristics of Swell-Shrink Soils in Kibaha, Tanzania." Tanzania Journal of Engineering and Technology 30, no. 2 (December 31, 2007): 92–97. http://dx.doi.org/10.52339/tjet.v30i2.402.
Повний текст джерелаАнотація:
The properties of Swell-shrink of the soils in Kibaha were studied. Geotechnical and mineralogical tests were carried outon disturbed and undisturbed samples recovered from trial pits at different locations. Using empirical relationships, theswelling potential of the soil was established in correlation with the soil plasticity limits and grain size analysis (claycontents). The average values for the plastic, liquid and linear shrinkage limits for soils were 22.2%, 60.7% and 14.5%respectively. The plasticity Index (PI) which is the difference between liquid limits and plastic limits ranges from 27% to47.4% with an average of 38.5%. The natural water content is very small ranging from 7% to 11% with an average of9.6% which is smaller than the corresponding shrinkage limit.Furthermore, the samples were tested for percentage of volume change in free swell tests and swelling pressure in one-dimensional swell tests. The free swell and upward pressure were in the excess of 100% to 150% and 50 kParespectively. In addition, the coefficient of linear extensibility ranged from 0.09 to 0.14 signifying high to very high swell-shrink potential.Finally, the main clay mineral present in the sample was determined by running the X-ray diffraction (XRD) test. The x-ray diffraction scan indicated the presence of high proportion of clay minerals (smectite) in the soils.
11
Högström, Ulf, Erik Sahlée, Ann-Sofi Smedman, Anna Rutgersson, Erik Nilsson, Kimmo K. Kahma, and William M. Drennan. "Surface Stress over the Ocean in Swell-Dominated Conditions during Moderate Winds." Journal of the Atmospheric Sciences 72, no. 12 (November 30, 2015): 4777–95. http://dx.doi.org/10.1175/jas-d-15-0139.1.
Повний текст джерелаАнотація:
Abstract Atmospheric and surface wave data from several oceanic experiments carried out on the Floating Instrument Platform (FLIP) and the Air–Sea Interaction Spar (ASIS) have been analyzed with the purpose of identifying swell-related effects on the surface momentum exchange during near-neutral atmospheric conditions and wind-following or crosswind seas. All data have a pronounced negative maximum in uw cospectra centered at the frequency of the dominant swell np, meaning a positive contribution to the stress. A similar contribution at this frequency is also obtained for the corresponding crosswind cospectrum. The magnitude of the cospectral maximum is shown to be linearly related to the square of the orbital motion, being equal to , where Hsd is the swell-significant wave height, the effect tentatively being due to strong correlation between the surface component of the orbital motion and the pattern of capillary waves over long swell waves. A model for prediction of the friction velocity from measurements of Hsd, np, and the 10-m wind speed U10 is formulated and tested against an independent dataset of ~400 half-hour measurements during swell, giving good result. The model predicts that the drag coefficient CD, which is traditionally modeled as a function of U10 alone (e.g., the COARE algorithm), becomes strongly dependent on the magnitude of the swell factor and that CD can attain values several times larger than predicted by wind speed–only models. According to maps of the global wave climate, conditions leading to large effects are likely to be widespread over the World Ocean.
12
Setapa, Amanina, Naveed Ahmad, Shalela Mohd Mahali, and Mohd Cairul Iqbal Mohd Amin. "Mathematical Model for Estimating Parameters of Swelling Drug Delivery Devices in a Two-Phase Release." Polymers 12, no. 12 (December 5, 2020): 2921. http://dx.doi.org/10.3390/polym12122921.
Повний текст джерелаАнотація:
Various swelling drug delivery devices are promising materials for control drug delivery because of their ability to swell and release entrapped therapeutics, in response to physiological stimuli. Previously, many mathematical models have been developed to predict the mechanism of drug release from a swelling device. However, some of these models do not consider the changes in diffusion behaviour as the device swells. Therefore, we used a two-phase approach to simplify the mathematical model considering the effect of swelling on the diffusion coefficient. We began by defining a moving boundary problem to consider the swelling process. Landau transformation was used for mitigating the moving boundary problem. The transformed problem was analytically solved using the separation of variables method. Further, the analytical solution was extended to include the drug release in two phases where each phase has distinct diffusion coefficient and continuity condition was applied. The newly developed model was validated by the experimental data of bacterial cellulose hydrogels using the LSQCURVEFIT function in MATLAB. The numerical test showed that the new model exhibited notable improvement in curve fitting, and it was observed that the initial effective diffusion coefficient of the swelling device was lower than the later effective diffusion coefficient.
13
Kumar, Sujeet, Rakesh Kumar Dutta, and Bijayananda Mohanty. "Engineering Properties of Bentonite Stabilized with Lime and Phosphogypsum." Slovak Journal of Civil Engineering 22, no. 4 (December 1, 2014): 35–44. http://dx.doi.org/10.2478/sjce-2014-0021.
Повний текст джерелаАнотація:
Abstract Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the California bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. The content of the lime and phosphogypsum varied from 0 to 10 %. The results reveal that the dry unit weight and optimum moisture content of bentonite + 8 % lime increased with the addition of 8 % phosphogypsum. The percentage of swell increased and the free swell index decreased with the addition of 8 % phosphogypsum to the bentonite + 8 % lime mix. The unconfined compressive strength of the bentonite + 8 % lime increased with the addition of 8 % phosphogypsum as well as an increase in the curing period up to 14 days. The liquid limit and plastic limit of the bentonite + 8 % lime increased, whereas the plasticity index remained constant with the addition of 8 % phosphogypsum. The California bearing ratio, modulus of subgrade reaction, and secant modulus increased for the bentonite stabilized with lime and phosphogypsum. The coefficient of the consolidation of the bentonite increased with the addition of 8 % lime and no change with the addition of 8 % phosphogypsum.
14
Bu, Jinwei, Kegen Yu, Hyuk Park, Weimin Huang, Shuai Han, Qingyun Yan, Nijia Qian, and Yiruo Lin. "Estimation of Swell Height Using Spaceborne GNSS-R Data from Eight CYGNSS Satellites." Remote Sensing 14, no. 18 (September 16, 2022): 4634. http://dx.doi.org/10.3390/rs14184634.
Повний текст джерелаАнотація:
Global Navigation Satellite System (GNSS)-Reflectometry (GNSS-R) technology has opened a new window for ocean remote sensing because of its unique advantages, including short revisit period, low observation cost, and high spatial-temporal resolution. In this article, we investigated the potential of estimating swell height from delay-Doppler maps (DDMs) data generated by spaceborne GNSS-R. Three observables extracted from the DDM are introduced for swell height estimation, including delay-Doppler map average (DDMA), the leading edge slope (LES) of the integrated delay waveform (IDW), and trailing edge slope (TES) of the IDW. We propose one modeling scheme for each observable. To improve the swell height estimation performance of a single observable-based method, we present a data fusion approach based on particle swarm optimization (PSO). Furthermore, a simulated annealing aided PSO (SA-PSO) algorithm is proposed to handle the problem of local optimal solution for the PSO algorithm. Extensive testing has been performed and the results show that the swell height estimated by the proposed methods is highly consistent with reference data, i.e., the ERA5 swell height. The correlation coefficient (CC) is 0.86 and the root mean square error (RMSE) is 0.56 m. Particularly, the SA-PSO method achieved the best performance, with RMSE, CC, and mean absolute percentage error (MAPE) being 0.39 m, 0.92, and 18.98%, respectively. Compared with the DDMA, LES, TES, and PSO methods, the RMSE of the SA-PSO method is improved by 23.53%, 26.42%, 30.36%, and 7.14%, respectively.
15
Li, Bo, Junmin Li, Shilin Tang, Ping Shi, Wuyang Chen, and Junliang Liu. "Evaluation of CFOSAT Wave Height Data with In Situ Observations in the South China Sea." Remote Sensing 15, no. 4 (February 6, 2023): 898. http://dx.doi.org/10.3390/rs15040898.
Повний текст джерелаАнотація:
The wave spectrometer operated by the China–France Oceanography Satellite (CFOSAT) can provide global ocean wave observation data. Although a lot of work on calibration and verification has been carried out in the open oceans dominated by swells, the quality of the data in the relatively enclosed sea area with complex terrain still lacks sufficient examination. The objective of this study is to assess the performance of the significant wave height data of the CFOSAT in the South China Sea (SCS), a unique sea area characterized by semi-enclosed basin and multi-reef terrain, and to recognize the environmental factors affecting the data quality. Compared against the long-term observations from five mooring or buoy sites, we find that the data is well performed in the relatively open and deep areas of the SCS, with an average correlation coefficient as high as 0.87, and a low average root-mean-square error of 0.47 m. However, the combined effects of complex topography, monsoons, and swell proportion variation will affect the performance of data. In the southern deep areas, the waves may be affected by a large number of dotted reefs, leading to wave deformations and energy dissipation in different seasons. In the northern nearshore areas, waves tend to be sheltered by the land or distorted by the shallow topography effects. These processes make it difficult for the swell to fully develop as in the open oceans. The low proportion of swell is a disadvantage for the CFOSAT to correctly observe the wave data and may lead to possible errors. Our results emphasize the importance of more verification when applying the CFOSAT data in certain local seas, and the necessity to adjust the algorithm of inverting wave spectra according to specific environmental factors.
16
Sullivan, Peter P., James B. Edson, Tihomir Hristov, and James C. McWilliams. "Large-Eddy Simulations and Observations of Atmospheric Marine Boundary Layers above Nonequilibrium Surface Waves." Journal of the Atmospheric Sciences 65, no. 4 (April 1, 2008): 1225–45. http://dx.doi.org/10.1175/2007jas2427.1.
Повний текст джерелаАнотація:
Abstract Winds and waves in marine boundary layers are often in an unsettled state when fast-running swell generated by distant storms propagates into local regions and modifies the overlying turbulent fields. A large-eddy simulation (LES) model with the capability to resolve a moving sinusoidal wave at its lower boundary is developed to investigate this low-wind/fast-wave regime. It is used to simulate idealized situations with wind following and opposing fast-propagating waves (swell), and stationary bumps. LES predicts momentum transfer from the ocean to the atmosphere for wind following swell, and this can greatly modify the turbulence production mechanism in the marine surface layer. In certain circumstances the generation of a low-level jet reduces the mean shear between the surface layer and the PBL top, resulting in a near collapse of turbulence in the PBL. When light winds oppose the propagating swell, turbulence levels increase over the depth of the boundary layer and the surface drag increases by a factor of 4 compared to a flat surface. The mean wind profile, turbulence variances, and vertical momentum flux are then dependent on the state of the wave field. The LES results are compared with measurements from the Coupled Boundary Layers Air–Sea Transfer (CBLAST) field campaign. A quadrant analysis of the momentum flux from CBLAST verifies a wave age dependence predicted by the LES solutions. The measured bulk drag coefficient CD then depends on wind speed and wave state. In situations with light wind following swell, CD is approximately 50% lower than values obtained from standard bulk parameterizations that have no sea state dependence. In extreme cases with light wind and persistent swell, CD < 0.
17
DASOG, G. S., D. F. ACTON, A. R. MERMUT, and E. DE JONG. "SHRINK-SWELL POTENTIAL AND CRACKING IN CLAY SOILS OF SASKATCHEWAN." Canadian Journal of Soil Science 68, no. 2 (May 1, 1988): 251–60. http://dx.doi.org/10.4141/cjss88-025.
Повний текст джерелаАнотація:
Clay soils in Saskatchewan were studied to understand their shrink-swell potential, to identify soil properties that predict the coefficient of linear extensibility (COLE), and to assess the extent of cracking during the growing season. The soils have medium to very high shrink-swell potential, which is related to the specific surface area associated with expandable clays. Because expandable clays in these soils are predominantly of fine clay size, COLE is reasonably well predicted from percent fine clay. The extent of cracking is estimated for some sites using an improved method of measurement. Limited data suggest that cracking intensity in native grassland is less than in cultivated sites and that, under wheat, it is more pronounced in subarid than in subhumid sites. The magnitude of cracking in clay soils of Saskatchewan is much lower than in warmer regions of the world. It is suggested that COLE values and the extent of cracking could be used in improving the classification of clay soils. Key words: Clay soils, COLE, shrink-swell potential, shrinkage, cracking, Saskatchewan
18
Vledder, Gerbrant Van, Marcel Zijlema, and Leo Holthuijsen. "REVISITING THE JONSWAP BOTTOM FRICTION FORMULATION." Coastal Engineering Proceedings 1, no. 32 (January 27, 2011): 41. http://dx.doi.org/10.9753/icce.v32.waves.41.
Повний текст джерелаАнотація:
The derivation of the JONSWAP bottom friction for wind-driven seas is revisited. This is motivated by the fact that
in the literature two different values for the corresponding coefficient are recommended, one value applicable for
swell conditions and a significantly higher value for wind-driven sea conditions. The value applicable for winddriven
seas was originally determined by Bouws and Komen (1983) who studied the source term balance of a
remarkably stationary storm in shallow water. We used a more accurate interpretation of these observations by
hindcasting this storm with the third-generation wave model SWAN. In addition, we compare wave model results
with measurements in the Wadden Sea and with parametric growth curves, some of which were obtained in Lake
George, Australia. The results strongly suggest that the lower bottom friction value of Cb=0.038 m2s-3 is applicable
for both wind-sea and swell conditions.
19
Umbugadu, A. A., M. I. Ancho, and Nghargbu K’tso. "Determination of Swell Potential of Soils using Cole in Panyam, North – Central Nigeria." European Journal of Environment and Earth Sciences 2, no. 5 (September 13, 2021): 1–4. http://dx.doi.org/10.24018/ejgeo.2021.2.5.164.
Повний текст джерелаАнотація:
Swell potential of soils from parts of Panyam, North – Central Nigeria were investigated covering 72 square kilometres within latitudes N9021′ and N9026′ and longitudes 9011′E and 9015′30″E. With the increase of civil engineering constructions and the scramble for limited portions of competent soils for such constructions, there is an urgent need in a developing nation to study and characterize such soils based on its geotechnical properties. The geotechnical studies include twenty soil samples taken within the 1.5m depth with the aim of determining the swell potential in order to give appropriate guide to any civil engineering design and construction. The direct method of soil analysis which is the coefficient of linear extensibility (COLE), which ranges from 0.02–0.17 was used for the study. COLE Values greater than 0.06, were considered to be critical for most civil engineering design and constructions. Most of the samples studied were considered not safe for bungalows and some infrastructure without proper safety measures carried out to improve upon it.
20
Casaverde-Pacherrez, Luis Alberto, Carmen Téllez-Pérez, Colette Besombes, Daniel Marcelo-Aldana, Karim Allaf, and Edilberto Vásquez-Díaz. "Effect of Swell-Drying on Mango (Mangifera indica) Drying Kinetics." Foods 11, no. 15 (July 26, 2022): 2220. http://dx.doi.org/10.3390/foods11152220.
Повний текст джерелаАнотація:
Swell-Drying operation (SD) was applied on mangoes to evaluate its effect on drying kinetics: starting accessibility (δW), apparent drying coefficient (Dapp), and time to obtain a final moisture content of 20% d.b (tf = 20% d.b). Swell-drying consisted of (1) submitting fresh mangoes to a first pre-drying stage under Convective Air Drying (CAD) until a moisture content of 37% d.b; (2) applying Instant Controlled Pressure Drop (DIC) treatments on pre-dried mangoes by following a central composite rotatable design (steam pressure: 0.2–0.6 MPa and treatment time: 5 and 55 s); and (3) apply post-drying of mangoes under CAD. In both cases, CAD was performed at 60 °C and airflow of 1 m/s. Results showed that both the treatment time and the steam pressure impacted the Dapp and the δW. By comparing to the control, SD (0.54 MPa and 48 s) increased the Dapp and δW to 12.2 and 2.7 times, respectively. Moreover, SD triggers a significant reduction in post-drying time (tf = 20% d.b), being this of 2.4 h vs. 30.8 h. These results could be linked to the expansion of the internal pores of mangoes generated by the instant autovaporization of residual water triggered by DIC treatment.
21
Amimi, M., S. Naasse, and C. Chahine. "Use of the corrected plane wave model for the determination of the reflection coefficient during horizontal plate swell interaction." MATEC Web of Conferences 286 (2019): 09001. http://dx.doi.org/10.1051/matecconf/201928609001.
Повний текст джерелаАнотація:
The main objective of this work, is to calculate variations of the reflection coefficient of the regular wave by a submerged horizontal plate, using the corrected plane wave model, by choosing appropriately the immersion and the relative length of the plate. It is shown that with this correction the reflection coefficient has a good agreement with the experimental results (Brossard et al., Liu C.R).
22
Jong, E. De, L. M. Kozak, and H. B. Storehouse. "Comparison of shrink-swell indices of some Saskatchewan soils and their relationships to standard soil characteristics." Canadian Journal of Soil Science 72, no. 4 (November 1, 1992): 429–39. http://dx.doi.org/10.4141/cjss92-036.
Повний текст джерелаАнотація:
Shrink-swell indices for 27 soil samples (representing the major horizons of eight soil profiles) were determined and related to soil texture, organic and inorganic C content, and specific surface area. The coefficient of linear extension was measured from saturation and from 33 kPa matric suction to oven-dryness on undisturbed clods (COLEclod) and on remolded samples of the less than 2-mm fraction (COLErod); the Atterberg limits were determined on the less than 0.4-mm fraction. COLEclod, COLErod and the plasticity index were highly correlated with each other and with clay content and surface area, but not with organic or inorganic C. The extent of the shrinkage was significantly (P > 0.01) related to the water content at the start of the shrinkage test; this relationship was clearer for the remolded than the undisturbed samples, possibly due to the structure of the clods. Key words: Coefficient of linear extension, plasticity index, clods vs. remolded, texture, organic carbon
23
Hwang, Paul A., Héctor García-Nava, and Francisco J. Ocampo-Torres. "Dimensionally Consistent Similarity Relation of Ocean Surface Friction Coefficient in Mixed Seas*." Journal of Physical Oceanography 41, no. 6 (June 1, 2011): 1227–38. http://dx.doi.org/10.1175/2011jpo4566.1.
Повний текст джерелаАнотація:
Abstract Applying wavelength scaling, dimensionally consistent expressions of the ocean surface friction coefficient can be developed for both wind sea and mixed sea in the ocean. For a wind sea with a monopeak wave spectrum, the natural choice of the scaling wavelength is that of the spectral peak component. For a mixed sea with a multipeak spectrum, the peak component in the wind sea portion of the wave spectrum is not a good reference wavelength. A much better scaling wavelength is the weighted average of swell and wind sea following the consideration of equivalent momentum in the wave field. The resulting friction coefficient Cλ/2 is referenced to the wind speed at one-half of the scaling wavelength Uλ/2 instead of C10 referenced to the neutral wind speed at 10-m elevation U10. Although referencing the wind speed at a fixed elevation such as U10 is of practical necessity, Uλ/2 is physically significant as the free-stream velocity in wave-modulated boundary layer flows. A simple procedure to apply the similarity relation of Cλ/2 to obtain C10 is described.
24
Jayaraman, Krishnan, Ying Leong Foong, and Tsun Hei Tam. "Assessment of Extruded Wood Plastic Composite Decking Materials." Advanced Materials Research 123-125 (August 2010): 1111–14. http://dx.doi.org/10.4028/www.scientific.net/amr.123-125.1111.
Повний текст джерелаАнотація:
Wastes such as saw dust (Pinus Radiata) and milk bottles (High Density Polyethylene - HDPE) are available in abundance. Composite decking materials, consisting of different weight percentages (60%, 70% and 80%) of saw dust and recovered HDPE, were extruded using a co-rotating, conical, twin screw extruder with a decking-profile die. The extruded decking materials were evaluated on their surface finish and shape conformance. The extruded decking materials were tested in accordance with the appropriate ASTM standards to determine their water absorption, thickness swell, static coefficient of friction, weathering and flexural (four-point bending) properties after they met the required quality ratings.
25
Suzuki, Naoya, Yoshiaki Toba, and Satoru Komori. "Examination of drag coefficient with special reference to the windsea Reynolds number: Conditions with counter and mixed swell." Journal of Oceanography 66, no. 5 (September 18, 2010): 731–39. http://dx.doi.org/10.1007/s10872-010-0060-6.
Повний текст джерела
26
Orimoloye, Stephen, Harshinie Karunarathna, and Dominic E. Reeve. "Reflection Analysis of Impermeable Slopes under Bimodal Sea Conditions." Journal of Marine Science and Engineering 8, no. 2 (February 18, 2020): 133. http://dx.doi.org/10.3390/jmse8020133.
Повний текст джерелаАнотація:
Understanding of the reflection characteristics of coastal seawalls is crucial for design. Wave reflection can cause difficulties in small vessel manoeuvring at harbour entrances; this can cause damage to the toe of coastal structures by scouring. Previous studies have examined the reflection characteristics of coastal seawalls under random wind-generated waves without considering the effects of wave bimodality created by the presence of swell waves. This present study focuses on the influence of random wave bimodality on the reflective characteristics of coastal seawalls. 823 experimental tests were conducted to examine the reflection performance of impermeable sloping seawalls under bimodal waves. Reflection coefficients were computed from each test. The analysis of the results suggests that both unimodal and bimodal waves give similar reflection characteristics. However, the reflection coefficient in bimodal sea states seems to be more prolonged than in the unimodal sea states. It was found that the reflection coefficients of coastal seawalls are strongly influenced by the seawall slope, the wave steepness, the relative water depth, and the surf similarity parameters. A new empirical reflection equation to describe the influence of wave bimodality on the reflection characteristics of coastal seawalls has been formulated based on this study.
27
Welling, D. J., and L. W. Welling. "Model of renal cell volume regulation without active transport: role of a heteroporous membrane." American Journal of Physiology-Renal Physiology 255, no. 3 (September 1, 1988): F529—F538. http://dx.doi.org/10.1152/ajprenal.1988.255.3.f529.
Повний текст джерелаАнотація:
Isolated proximal renal tubules of rabbit reach a passive steady-state volume in isotonic medium after active transport is inhibited by ouabain or by inhibition of cellular metabolism or lack of metabolic substrates. If the tubules are then placed in a hypotonic NaCl medium they swell rapidly and then exhibit a volume regulatory decrease (VRD) similar to that seen when active transport is present. We have mathematically modeled these transient events by assuming that the basolateral cell membrane is permeated by pores having at least two distinct reflection coefficients with respect to sodium, potassium, and chloride. VRD depends on the difference of the values of the reflection coefficients of the pore types. As hydrostatic pressure is exerted by the stretching basement membrane, water and ions can be expelled from the cells across the lower reflection coefficient pores and cause VRD. When the hydrostatic pressure compliance is removed, the cells fail to volume decrease unless sufficient extracellular impermeant solute is present to provide an osmotic force for water and ion exit. We conclude that a heteroporous membrane may be an essential feature for cell volume regulation and maintenance.
28
Jadhav, Ranjit S., and Qin Chen. "FIELD INVESTIGATION OF WAVE DISSIPATION OVER SALT MARSH VEGETATION DURING TROPICAL CYCLONE." Coastal Engineering Proceedings 1, no. 33 (October 25, 2012): 41. http://dx.doi.org/10.9753/icce.v33.waves.41.
Повний текст джерелаАнотація:
Wave data were measured along a 28 m transect using 3 pressure transducers over a 2-day period during a tropical storm. The tropical storm force winds produced waves up to 0.4 m high (zero-moment) that propagated over vegetation of Spartina alterniflora submerged under a surge of over 1 m above the marsh floor. Measured wave heights, energy losses between gages and spectral energy dissipation models of rigid vegetation were utilized to estimate wave height decay rates, integral and frequency-dependent bulk drag coefficients, and frequency distribution of energy dissipation induced by the vegetation. Measurements showed that incident waves attenuated exponentially over the vegetation. The exponential wave height decay rate decreased as Reynolds number increased. The swell was observed to decay at a slower rate than the wind sea regardless of the wave height. The linear spatial wave height reduction rate increased from 1.5% to 4% /m as incident wave height decreased. The bulk drag coefficient estimated from the field measurement decreased with increasing Reynolds and Keulegan-Carpenter numbers. The energy dissipation varied across the frequency scales with the largest magnitude observed near the spectral peaks, above which the dissipation gradually decreased. The wave energy dissipation did not linearly follow the incident energy, and the degree of non-linearity varied with the frequency. For a given spectrum, the frequency-distributed drag coefficient increased gradually up to the peak frequency and remained approximately at a stable value at the higher frequencies. This spectral variation was parameterized by introducing a frequency-dependent velocity attenuation parameter inside the canopy. The spectral drag coefficient is shown to predict the distribution of energy dissipation with more accuracy than the integral coefficients, which results in a more accurate prediction of the mean wave period and spectral width of a wave field with vegetation.
29
Dominijanni, Andrea, Nicolò Guarena, and Mario Manassero. "Laboratory assessment of semi-permeable properties of a natural sodium bentonite." Canadian Geotechnical Journal 55, no. 11 (November 2018): 1611–31. http://dx.doi.org/10.1139/cgj-2017-0599.
Повний текст джерелаАнотація:
The relevance of the semi-permeable properties of bentonites, which affect both their transport processes and mechanical behaviour, has been assessed through the experimental determination of three parameters: the reflection coefficient, ω; the osmotic effective diffusion coefficient, [Formula: see text]; and the swell coefficient, ϖ. Two multi-stage tests were conducted on a natural sodium bentonite, while varying both the specimen void ratio, e, and the solute concentration, cs, of the equilibrium sodium chloride (NaCl) solutions. The measured phenomenological parameters were interpreted through a mechanistic model, in which the electric charge of clay particles is taken into account via a single material parameter, [Formula: see text], referred to as the “solid charge coefficient”. A constant value of [Formula: see text] = 110 mmol/L was found to provide an accurate interpretation of the experimental data, at least within the investigated range of bentonite void ratios (3.33 ≤ e ≤ 4.18) and NaCl concentrations of the external bulk solutions (5 ≤ cs ≤ 90 mmol/L). The results support the hypothesis that both chemical osmosis and swelling pressure are macroscopic manifestations of the same interactions, which occur at the microscopic scale between the clay particles and the ions contained in the pore solution, and that both of them can be modelled through a single theoretical framework.
30
Millenia P, Devinta, Amanda Safira, Widya Utama, Trihanyndio Rendy S, Rista F. Indriani, Dhea P. N. Putra, and Sherly A. Garini. "GEOMETRY ASSESSMENT ON THE SLOPE STABILITY OF MANYAR POND." Malaysian Journal of Civil Engineering 34, no. 3 (November 30, 2022): 11–15. http://dx.doi.org/10.11113/mjce.v34.18710.
Повний текст джерелаАнотація:
Lateritic soil was treated with 0%, 4%, 8%, 12%, and 16% Rice Husk Ash (RHA) by dry soil weight to determine its consolidation properties. Test carried out include particle size distribution, specific gravity, compaction test with varying compactive efforts (British Standard Light (BSL), West African Standard (WAS) as well as British Standard Heavy (BSH)) and consolidation test. Samples for consolidation test were compacted and then cured for 7, 28 and 56 days; then subjected to one dimensional consolidation testing to observe the influence of curing period and compactive effort on its consolidation characteristics. Index tests showed improved geotechnical properties. The Maximum Dry Density (MDD) for BSL compaction decreased with a rise in RHA content from 1.72 to 1.42 Mg/m3 while optimum moisture content (OMC) increased from 16.5% to 27.3% with rise in RHA doses from 0% up to 16%. Similar trend was observed for WAS and BSH energies. Pre-consolidation pressure rise with increment in RHA content and also with increase in both compactive efforts and curing period with few exceptions. At 12% RHA content, Pre-consolidation pressure increased from 65 to 66.5 kN/m2 at 7 days and 56 days respectively. Increase in RHA content caused a decrease in Compression Index and Swelling Index. Compression Index also decreased with increase in both compactive efforts and curing period. There was no observed trend in the Swell Index with curing period. As the compactive efforts increased, the swell index decreased. The RHA reduced the Coefficient of Volume Compressibility (Mv) and the Coefficient of Consolidation (Cc). Curing period and compactive effort have no effect on Mv and Cc. Based on the results obtained, curing period at least 28 days using up to 12% RHA compacted at energy level of BSH improved the properties of the treated soil and can be used for geotechnical engineering applications like embankment or rural roads.
31
Sahlée, Erik, Ann-Sofi Smedman, Ulf Högström, and Anna Rutgersson. "Reevaluation of the Bulk Exchange Coefficient for Humidity at Sea during Unstable and Neutral Conditions." Journal of Physical Oceanography 38, no. 1 (January 1, 2008): 257–72. http://dx.doi.org/10.1175/2007jpo3754.1.
Повний текст джерелаАнотація:
Abstract Processes influencing the air–sea exchange of humidity during unstable and neutral stratification were studied using tower measurements from the island of Östergarnsholm in the Baltic Sea. For small air–sea temperature differences, the neutral exchange coefficient for humidity CEN was found to increase with increasing wind speed, attaining a value of approximately 1.8 × 10−3 at 13 m s−1. The high CEN values were observed during situations when the characteristics of the turbulence structure differed from what would be expected from traditional theory. Results from spectral analysis point to a situation in which the vertical transport of humidity is dominated by smaller-scale eddies. Quadrant analysis showed that these eddies enhance the humidity flux by bringing down drier air from layers aloft. These findings are consistent with recent analyses of the neutral boundary layer in which a change of turbulence regime has been observed. The conclusion is made that this dynamic effect accounts for the observed increase in CEN. Here, CEN was calculated using a wave-dependent normalized wind gradient, which had the effect of reducing the value by about 10% during swell relative to calculations using a non-wave-dependent normalized wind gradient.
32
Iqbal, Kamran, Chengshun Xu, Hassan Nasir, Muhammad Alam, Asim Farooq, and Edward J. Williams. "Effect of Used Motor Oil and Bitumen as Additive on the Permeability and Mechanical Properties of Low Plastic Soil." Advances in Materials Science and Engineering 2020 (July 30, 2020): 1–10. http://dx.doi.org/10.1155/2020/1360197.
Повний текст джерелаАнотація:
Stability of permeable soils near large-scale water reservoirs for paved and unpaved road pavements is all too frequently compromised due to excessive seepage and the climatic conditions of that area. In this research, a multilevel research approach was adopted by conducting a comparative study of the microspectroscopy through Fourier transform infrared (FTIR) spectra to investigate the maximum absorbance correlation along with mechanical investigations (such as the compressive strength, modified proctor test, California bearing ratio test, and swell percentage test). The native low plastic soil sample (CL) was blended with varying percentages of petroleum additives (bitumen and used motor oil) independently at 0%, 4%, 8%, 12%, 16%, and 20%. A comparison of results in the case of bitumen and used motor oil revealed that a decrease in Atterberg’s limits occurred accompanied by an increase of bitumen blending percentage, while used motor oil (UMO) increased the plastic limit. Maximum dry density (MDD) increases while optimum moisture content (OMC) decreases with the increase in bitumen. Used motor oil (UMO) initially (up to 4%) increased the MDD and subsequently decreased it. Investigative reports show that bitumen causes a decrease in swell percentage and increases California bearing ratio (CBR), whereas UMO causes a continuous increase in percentage swell and decrease in CBR. The addition of bitumen in soil resulted in a decrease in the coefficient of permeability (k), while UMO has a significant result of up to 4%. Regarding the control sample, spectrum analysis through FTIR effectively supports the laboratory results as the intensity of peaks increases with the oil, and bitumen concentration reveals that oil and bitumen impart cementitious property to the soil. Moreover, this research work by experiment supported and strengthened the idea of soil pavement stabilization through bitumen, which gives antiwater stability, and facilitates low-cost construction by obtaining raw material on the spot. UMO adversely affects soil properties beyond 4% addition by weight.
33
Cosmulescu, Sina, Maria Marina Merca Laies, and Veronica Sărățeanu. "The Influence of Variety and Climatic Year on the Phenology of Blueberry Grown in the Banat Area, Romania." Agronomy 12, no. 11 (October 23, 2022): 2605. http://dx.doi.org/10.3390/agronomy12112605.
Повний текст джерелаАнотація:
This paper’s aim was to investigate the influence of variety and the climatic year on vegetation phenophases in blueberries grown in southwest Romania, the Banat region. This study was carried out during the growing season of 2020–2022 in a blueberry plantation, for ‘Duke’, ‘Hannah’s Choice’ and ‘Elliott’ varieties. In the study, phenological traits were recorded using the BBCH phenological scale and the observation of phenotypic data was recorded as in Julian days. Thus, it is found that the duration of each phenophase characterized each variety. The calendar periods for the onset of vegetation and the duration of spring phenological development stages in varieties have differed from year to year and depended on weather conditions. In the case of the phenological stage, depending on variety, the maximum amplitude was recorded for BBCH 87 stage (75% blue fruits) of 51 days, and the minimum amplitude, of 25 days, for BBCH 51 stage (bud swell) and BBCH 59 (late pink bud). The coefficient of variation, depending on climatic year, for generative phenophases, had values between 6.5% (BBCH 67-petal fall) and 21.1% (BBCH 51-bud swell). It was found that the variety and the climatic year influence the development of vegetation phenophases. The results indicate that blueberry cultivars have demonstrated a high degree of phenotypic plasticity to respond to gradual changes in environmental conditions and are important for the evaluation of cultivar cultivation prospects in the studied area.
34
Adrian Oshioname, Eberemu, Yohanna Paul, Aliyu Mustapha, and Abdu-Aguye Abdullahi. "CONSOLIDATION CHARACTERISTICS OF LATERITIC SOIL TREATED WITH RICE HUSK ASH." Malaysian Journal of Civil Engineering 34, no. 1 (March 24, 2022): 19–28. http://dx.doi.org/10.11113/mjce.v34.17663.
Повний текст джерелаАнотація:
Lateritic soil was treated with 0, 4, 8, 12 and 16% rice husk ash (RHA) by dry weight of soil to determine its consolidation properties. Test carried out include; particle size distribution, specific gravity, compaction test with varying compactive efforts (British Standard Light (BSL), West African Standard (WAS) as well as British Standard Heavy (BSH)) and consolidation test. Samples for consolidation test were compacted and then cured for 7, 28 and 56 days; then subjected to one dimensional consolidation testing to observe the influence of curing period and compactive effort on its consolidation characteristics. Index tests showed improved geotechnical properties. The maximum dry density (MDD) for BSL compaction decreased with a rise in RHA content from 1.72 to 1.42 Mg/m3 while optimum moisture content (OMC) increased from 16.5 to 27.3% with rise in RHA doses from 0 up to 16%. Similar trend was observed for WAS and BSH energies. The Pre-consolidation pressure rise with increment in RHA content and also with increase in both compactive efforts and curing period with few exceptions. At 12% RHA content, the Pre-consolidation pressure increased from 65 to 66.5kN/m2 at 7 days and 56 days respectively. Increase in RHA content caused a decrease in Compression Index (Cc) and Swelling Index (Cs). Compression Index also decreased with increase in both compactive efforts and curing period. There was no observed trend in the Swell Index with curing period. As the compactive efforts increased, the swell index decreased. The RHA reduced the Coefficient of Volume Compressibility (Mv) and the Coefficient of Consolidation (Cc). Curing period and compactive effort have no effect on Mv and Cc. Based on the results obtained, curing period of atleast 28 days using up to 12% RHA compacted at energy level of BSH improved the properties of the treated soil and can be use for geotechnical engineering applications like embankment or rural roads.
35
Chamberlin, K. S., and M. Rama Rao. "Influence of Lime for Enhancing Characteristics of Expansive Soils in Road Works." IOP Conference Series: Materials Science and Engineering 1197, no. 1 (November 1, 2021): 012077. http://dx.doi.org/10.1088/1757-899x/1197/1/012077.
Повний текст джерелаАнотація:
Abstract Expansive soils are found in black cotton soils, which swell or shrink in volume when presented to changes in moisture content. Lime treatment is exhaustively used to increment the properties of sensitive and fragile soils. One of the hugest clarifications behind using lime is to decline the developing presentation of the earth soil. The arrangement of extra safeguards improves the reaction of quicklime (CaO) with water, structures hydrated (slaked) lime (Ca (OH)2), and thus earth characteristics. The vast inadequacy of employing lime is growing the deficiency of lime offset earth. Following that, the goal of this study is to see how re-establishing time affects the geotechnical qualities of settled Black cotton soils with lime. These discoveries recommend that adding Lime as a stabilizer works on the strength of black cotton soil. Some of the characteristics of the soil likely to be increased by using stabilizer in this work are UCS (Unconfined Compressive Strength) at different curing periods (7,14,28 and 56 days), CBR (California Bearing Ratio) value at unsoaked and soaked and MDD (Maximum Dry Density) decrease at different lime percentages(%) like 2.4.6.8 and 10. The result showed here untreated soil got stabilized by using the stabilizer in certain extent In this adjustment various rates of cementitious material is added to black cotton soil and directed tests like plasticity, compaction, swell pressure, free swell index(FSI), Coefficient of permeability (k) and CBR(soaked and unsoaked) at various conditions like OMC,OMC+2% water and OMC+5% water, UCS (Unconfined Compressive Strength) was performed. From the test results, it is identified that the stabilization agent decreases plasticity and improves strength characteristics. Addition of stabilizing agent makes the black cotton soil to non-plastic, non-swelling and attains increase CBR values which are greater than 25% for a dosage of 10% lime at OMC but remaining OMC+2%water & OMC+5%water CBR values are not various much difference as per test results. With the addition of lime, the black cotton soil becomes non-plastic, non-swelling, and has high strengths. Treated soils are used as a development material, for example, a subgrade layer in the development of adaptable asphalt pavements for roads.
36
Hutchinson, Steven, Martin Young, and Alasdair Macleod. "CAISSON BREAKWATER DESIGN FOR SLIDING." Coastal Engineering Proceedings 1, no. 32 (January 25, 2011): 48. http://dx.doi.org/10.9753/icce.v32.structures.48.
Повний текст джерелаАнотація:
The offshore caisson breakwater at Costa Azul installed in 25m water depth is designed to withstand Pacific swell waves up to a PLS test case Hs 9.2m Tp 18.6s. Overall stability design is in accordance with the recommendations of PIANC WG 28. The critical failure mechanism is sliding, and the caisson base is cast with a deliberately roughened (serrated) profile to increase sliding resistance and optimize the caisson cross section. Site based testing at prototype scale was conducted to validate the coefficient of friction used for design between the caisson base and nominal 100mm single size granular bedding material. This testing confirms that the use of a suitably dimensioned serrated base profile allows the full internal angle of friction (with allowance for dilation) of the bedding material to develop at the base of the caisson, allowing the cross section design to be optimized.
37
Wu, Lichuan, Tihomir Hristov, and Anna Rutgersson. "Vertical Profiles of Wave-Coherent Momentum Flux and Velocity Variances in the Marine Atmospheric Boundary Layer." Journal of Physical Oceanography 48, no. 3 (March 2018): 625–41. http://dx.doi.org/10.1175/jpo-d-17-0052.1.
Повний текст джерелаАнотація:
AbstractThe wave-coherent momentum flux and velocity variances are investigated using a theoretical model and open-ocean measurements. The spectrum-integrated wave-coherent (SIWC) momentum flux and velocity variances decay roughly exponentially with height. The exponential decay coefficients of the SIWC momentum flux and velocity variances decrease with increasing peak wavenumber. The phases of the wave-coherent horizontal (vertical) velocity fluctuations are approximately 180° (90°) under waves with wind-wave angle |α1| < 90°. In general, the ratio of the SIWC momentum flux to the total momentum flux under swell conditions is higher than that under wind-wave conditions at the same height. At a height of 9.9 m, the SIWC vertical (horizontal) velocity variances can exceed 30% (10%) of the total vertical (horizontal) velocity variances at high wave ages. The impact of SIWC momentum flux on wind profiles is determined mainly by the surface SIWC momentum flux ratio, the decay coefficient of the SIWC momentum flux, and the sea surface roughness length, with the first two factors being dominant. The results of this study suggest a methodology for parameterizing the SIWC momentum flux and the total momentum flux over the ocean. These results are important for simulating the marine atmospheric boundary layer and should be used in model development.
38
Widomski, Marcin K., Anna Musz-Pomorska, and Wojciech Franus. "Hydraulic and Swell–Shrink Characteristics of Clay and Recycled Zeolite Mixtures for Liner Construction in Sustainable Waste Landfill." Sustainability 13, no. 13 (June 29, 2021): 7301. http://dx.doi.org/10.3390/su13137301.
Повний текст джерелаАнотація:
This paper presents research considering hydraulic as well as swelling and shrinkage characteristics of potential recycled fine particle materials for compacted clay liner for sustainable landfills. Five locally available clay soils mixed with 10% (by mass) of NaP1 recycled zeolite were tested. The performed analysis was based on determined plasticity, cation exchange capacity, coefficient of saturated hydraulic conductivity after compaction, several shrinkage and swelling characteristics as well as, finally, saturated hydraulic conductivity after three cycles of drying and rewetting of tested specimens and the reference samples. The obtained results showed that addition of zeolite to clay soils allowed reduction in their saturated hydraulic conductivity to meet the required threshold (≤1 × 10−9 m/s) of sealing capabilities for compacted clay liner. On the other hand, an increase in plasticity, swelling, and in several cases in shrinkage, of the clay–zeolite mixture was observed. Finally, none of the tested mixtures was able to sustain its sealing capabilities after three cycles of drying and rewetting. Thus, the studied clayey soils mixed with sustainable recycled zeolite were assessed as promising materials for compacted liner construction. However, the liner should be operated carefully to avoid extensive dissication and cracking.
39
Tran, Oanh Thi, Khanh Duy Pham, Quy Van Hoang, Muoi Duy Nguyen, Ngan Thi Bui Ha Hai Thi Nguyen, Ngoc Bao Pham, and Hiep Le Quoc. "Application of artificial intelligence network to predict the distribution of volcanic material in sequence D, field X, Cuu Long basin." Journal of Mining and Earth Sciences 61, no. 5 (October 31, 2020): 104–13. http://dx.doi.org/10.46326/jmes.2020.61(5).12.
Повний текст джерелаАнотація:
The presence of volcanic materials in reservoir will reduce the porosity value and effect to the quality of reservoirs. Therefore, understanding the distribution of this object will be of great significance in the orientation of oil and gas exploration and exploitation. This paper applies seismic attribute analysis method combined with artificial neural network (ANN) application to predict the distribution of volcanic materials in D sequence. Attributes selected as input for ANN training including RMS, RAI and Specdecom attribute. The results indicate that volcanic materials mainly appear in the to the Southwest of block (around D well and the West of E well), a small part is scattered near Con Son swell. The correlation coefficient among seismic attribute is from 71 to ~ 80%, this shows that the reliability of the results of network training is relatively high. Therefore, this method can be used to predict the distribution of volcanic materials in the study area.
40
Pan, Yu Ping, Su Fang Ge, and Wen Yu Sha. "Comparison Studies on Sea Surface Roughness Schemes." Advanced Materials Research 610-613 (December 2012): 2751–55. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.2751.
Повний текст джерелаАнотація:
The data, originated from the RASEX experiment and the Surface Wave Dynamics Experiment. RASEX experiment took place at an offshore wind turbine site in the Baltic Sea in 1994, it is representative of the fetch-limited conditions; SWADE experiment was carried out off the Atlantic coast of the United States in 1990, it is representative of the wind-sea/swell conditions. Both datasets are used to test sea surface roughness schemes by using bulk algorithm. The aim of this study is to better understand the sensitively of the surface momentum fluxes to choice of surface roughness parameterization and the range of applicability of the four schemes (YT96, TY01, O02, and GW06). It was found YT96, TY01 and GW06 schemes generated friction velocity, drag coefficient and wind stress in good agreement with the direct measurements under different wind sea conditions, but O02 scheme overestimate them with the wind speed larger than 8ms-1 for the fetch-limited conditions.
41
Mckenzie, NJ, DJ Jacquier, and AJ Ringrose-Voase. "A rapid method for estimating soil shrinkage." Soil Research 32, no. 5 (1994): 931. http://dx.doi.org/10.1071/sr9940931.
Повний текст джерелаАнотація:
The Coefficient of linear extensibility (COLEstd) is often used by soil survey agencies to characterize the shrink-swell behaviour of soil. Undisturbed clods or cores are required but these are rarely collected during routine survey in Australia. The standard linear shrinkage test (LSstd) uses sieved soil and is often used as an alternative. However, the natural soil fabric is destroyed and the results can be difficult to relate to field behaviour. We have developed a modified linear shrinkage test (LSmod) in which disruption to the natural soil fabric is minimized. The LSmod was found to be a good predictor of COLEstd)(r2 = 0-88) with the slope of the regression line close to unity. LSstd was a weaker predictor of COLEstd. LSmod and LSstd were more precise measures than COLEstd. The modified method has been tested on a limited range of soils but a more comprehensive evaluation is required. This can be performed wherever COLEstd measurements have been made and sieved material is still available.
42
Abutaha, Saja Mohammad, Janos Geiger, and Sandor Gulyas. "Evaluation Of 3D small-scale lithological heterogeneities and pore distribution of the Boda Claystone Formation using X-Ray Computed Tomography images (CT)." Geologia Croatica 74, no. 3 (October 28, 2021): 305–18. http://dx.doi.org/10.4154/gc.2021.17.
Повний текст джерелаАнотація:
This study was undertaken to quantify and evaluate the density and porosity characteristics of a Boda Claystone Formation (BCF) core sample using medical CT. Each voxel of the 3D CT volume was described with three variables: dry CT number, saturated CT number, and effective porosity. Disparity pore voxels were revealed using the genetic groups’ algorithm of data-mining techniques. The K-fold cross-validation algorithm has been applied to determine the number of the most stable cluster. The 3D spatial distributions of voxel-porosity by rock constituents, as well as the 3D distribution of porosity clusters by rock components, were found by Boolean function implementation. The terrigenous detrital fragments had the lowest porosity mean (0.16%) and highest coefficient variation value (1039.39%). While the Fine siltstone component had the highest porosity mean (3.39%) and lower coefficient of variation (134.99%). The difference in the variation of coefficient proportions is related to the outlier ratios in each rock component. Independently of both the rock types and the sedimentary structures, two clusters could be defined: one for the micro-porosity and one for the macro-porosity regimes. The former showed a continuous 3D spatial appearance, while the latter appeared in patches. These patches may also be connected, at least partly, to some local smectite aggregates. These clay minerals could lose their structured water content during vacuuming and swell when adsorbing water during sample saturation. In each rock type, the micro-porosity regime could be related to low-density rock fragments. The mean effective porosity of the micro-pore regime was about 0.02, which corresponds to the petrophysical core measurements. For the macro regimes, the average was 0.1.
43
Akhtar, Maaz, Sayyad Zahid Qamar, Syed Murtuza Mehdi, and Ahmad Hussain. "Diffusion-based swelling in elastomers under low- and high-salinity brine." Journal of Elastomers & Plastics 51, no. 1 (September 9, 2018): 75–84. http://dx.doi.org/10.1177/0095244318796622.
Повний текст джерелаАнотація:
Swelling elastomers are designed to swell when immersed into fluids like water, oil, or acid. The mechanism of swelling can be either diffusion or osmosis, initiating the imbibition of fluid inside the elastomer and progressively swelling it. Work presented here investigates diffusion as the swelling mechanism. Swelling experiments are conducted at two temperatures (room and 50°C) using water of different salinities (0.6% and 12%) as the swelling medium. Changes in volume, thickness, mass, and hardness are recorded. Measurements are taken before swelling and after 1, 2, 4, 7, 10, 16, 23, and 30 days of swelling. As expected, volume, thickness, and mass of the elastomer increase with increase in the number of swelling days, while hardness shows a decreasing trend. More variation is observed for all quantities in low-salinity brine as compared to high salinity, at both temperatures. However, density values are larger for high-salinity brine at both temperatures. Stokes–Einstein formula is used to determine the diffusion coefficients. Viscosity is measured using a Cannon–Fenske apparatus of size 50. Larger values of diffusion coefficient are found in low-salinity water at both temperatures, consistent with the higher amount of swelling and the faster swelling rate. These results and the diffusion-based approach will help in understanding the mechanics of swelling phenomenon. This work can aid in the development of new analytical and semi-analytical models that can predict seal pressure and other performance factors more accurately for applications in oil and gas wells.
44
Niemirich, Alexandra, Oksana Melnyk, Oksana Petrusha, Andrew Havrysh, and Olga Koval. "TECHNOLOGICAL PROPERTIES OF THE POWDER MADE FROM JERUSALEM ARTICHOKE OBTAINED BY THE METHOD OF DRYING WITH MIXED HEAT SUPPLY." EUREKA: Life Sciences 2 (March 31, 2017): 42–50. http://dx.doi.org/10.21303/2504-5695.2017.00323.
Повний текст джерелаАнотація:
Present work addresses technological properties of powder made from Jerusalem artichoke, formed by the method of drying with mixed supply of heat, compared to traditional convection. It is shown that polysaccharides in the composition of Jerusalem artichoke of MHS-drying undergo less crystallization and hence drying is carried out under milder conditions than these components during convection method. We established capacity for the dispersing of dried Jerusalem artichoke in a traditional ball mill depending on the duration, which makes it possible to obtain dried products for various technological purposes. We demonstrated a capacity to swell in the resulting powder made from Jerusalem artichoke, which predetermines the formation of advanced capillary-porous structure. Results of the tensometric method of studies revealed that the formed structure of powder made from Jerusalem artichoke of MHS-drying is characterized by small pores at temperature 50 °С and by 1.2...1.5 times larger – at 70 °С, which must be considered when they are rehydrated. We examined a complex of basic functional-technological properties of powder made from Jerusalem artichoke: coefficient of water absorption (CW), water-retaining (WRC), fat-retaining (FRC) and emulsifying capacities (EC). During mathematical processing of the results received, we obtained a conceptual model that describes a dependence of the comprehensive indicator of technological properties of powder made from Jerusalem artichoke (by the defined weight coefficients: for CW – 0.2; WRC – 0.2; FRC – 0.3; EC – 0.2) depending on the temperature of MHS-drying and dispersibility.
45
Xu, Shuai, Ying Wang, Jianying Hu, and Zishun Liu. "Atomic Understanding of the Swelling and Phase Transition of Polyacrylamide Hydrogel." International Journal of Applied Mechanics 08, no. 07 (October 2016): 1640002. http://dx.doi.org/10.1142/s1758825116400020.
Повний текст джерелаАнотація:
A polymer network can imbibe copious amounts of solvent (water) and swell, and the resulting state is known as a hydrogel. In this study, we have made the modification for the all-atom consistent valence force field (CVFF) to investigate the swelling property of polyacrylamide (PAM) hydrogel by molecular dynamics simulation. We have built 21 hydrogel models with different solvent contents and calculate the average chemical potential and diffusion coefficient of solvent molecules in PAM hydrogel. We find that when the mass fraction of solvent is about 90%, PAM hydrogel reaches its free swelling limitation and loses the motivation of absorbing solvent. Furthermore, it is also found that PAM hydrogel has a phase transition phenomenon when the values of solvent chemical potential are between [Formula: see text][Formula: see text]kcal/mol and [Formula: see text][Formula: see text]kcal/mol. This study will provide insight into the basic parameters which are widely used in continuum mechanics analysis of hydrogels from atomic point of view and help researchers to improve the continuum mechanics model for neutral hydrogel.
46
Lim, Chin Hock, and Panmanas Sirisomboon. "Near infrared spectroscopy as an alternative method for rapid evaluation of toluene swell of natural rubber latex and its products." Journal of Near Infrared Spectroscopy 26, no. 3 (June 2018): 159–68. http://dx.doi.org/10.1177/0967033518783269.
Повний текст джерелаАнотація:
Toluene swell or equilibrium swelling is universally used by rubber factories to measure the degree of crosslink of their compounded or prevulcanized latices at different stages of production. To apply near infrared spectroscopy for rapid and accurate quality control, spectral acquisition of prevulcanized latex, thin film and thick film was performed using a Fourier transform near infrared spectrometer in diffuse reflection mode across the wavenumber range of 12,500–3600 cm−1. For prevulcanized latex an effective model was developed using partial least squares regression with preprocessing (first derivative + straight line subtraction method). The coefficient of determination (r2), root mean square error of cross validation and bias of the validation set were 0.71, 3.93% and −0.005%, respectively. For the thin film model the r2, root mean square error of cross validation and bias were 0.65, 4.01% and −0.028%, respectively. Whereas for the thick film model the r2, root mean square error of cross validation and bias were 0.70, 4.00% and −0.006%, respectively. Three models including prevulcanized latex, thin film and thick film were validated by 23 unknown samples, providing standard error of prediction and bias of 5.357 and 2.494, 4.565 and 1.001 and 3.641 and −0.961%, respectively, for prevulcanized latex, thin film and thick film. The model developed for the thick film spectra gave the best results.
47
Kujundžić, Trpimir, Mario Klanfar, Tomislav Korman, and Zlatko Briševac. "Influence of Crushed Rock Properties on the Productivity of a Hydraulic Excavator." Applied Sciences 11, no. 5 (March 6, 2021): 2345. http://dx.doi.org/10.3390/app11052345.
Повний текст джерелаАнотація:
Among many factors that influence an excavator’s performance and productivity, the volume of the bucket load and duration of the excavator working cycle are crucial. In this paper, both factors were investigated, including the granulometric composition of the excavated material. The volume of material in the bucket was determined by photogrammetric analysis while the excavator cycle time was measured by analysis of video recordings captured by a digital video camera during the excavator operation. Interconnections between the angle of repose, slewing angle, particle size distribution of material, and their effects on hydraulic excavator productivity were analyzed. It was found that a larger number of fine particles in granular materials with a higher coefficient of uniformity resulted in an increase in the volume of the bucket load. Correlation analysis revealed significant interconnection between the bucket fill factor and swell factor. It was also found that calculation of the production rate according to ISO (International Organization for Standardization) standards was more accurate for materials with a higher angle of repose while the CECE (Committee for European Construction Equipment) standard was more appropriate for materials with lower angles of repose.
48
Hwang, Paul A., Jakov V. Toporkov, Mark A. Sletten, and Steven P. Menk. "Mapping Surface Currents and Waves with Interferometric Synthetic Aperture Radar in Coastal Waters: Observations of Wave Breaking in Swell-Dominant Conditions*." Journal of Physical Oceanography 43, no. 3 (March 1, 2013): 563–82. http://dx.doi.org/10.1175/jpo-d-12-0128.1.
Повний текст джерелаАнотація:
Abstract Airborne and spaceborne interferometric synthetic aperture radars (InSARs) produce surface velocity measurements at very high spatial resolutions over a large area. The data allow construction of the velocity strain field for highlighting ocean surface processes such as wave breaking and rip currents. Also, coherence between signals from two interferometric channels is a descriptor of the correlation condition of the surface roughness that scatters back the radar signals and it is an indication of the ocean surface turbulence. Wave breaking is a major turbulence source causing surface roughness decorrelation, thus the coherence parameter serves as an independent means for detecting wave breaking. The results of breaking detection using roughness decorrelation and critical local acceleration are comparable. In this paper, the breaking fraction in swell-dominant mixed seas along a cross-shore transect is compared with several steepness parameters characterizing different length scales of surface waves. The highest correlation coefficient (from 0.90 to 0.99) is between the breaking fraction and windsea mean square slope contributed primarily by short waves. This result reinforces the previous field observations showing that the length scales of breaking waves are much shorter than the energetic components near the spectral peak, although dominant waves and the associated wave group modulation are important in triggering the breaking process. The large spatial coverage of airborne or spaceborne operation further offers the opportunity to investigate evolution of the surface wave spectrum in high spatial (subkilometer) resolution. This capability is very useful for monitoring the coastal wave and current environment.
49
Krinitsin, Nikita A., Vladimir K. Dubovy, Kseniya V. Polyakova, and Ivan N. Koverninsky. "Study of the Influence of Binder Type on the Properties of Glass Fiber Filter Paper for Air Purification." Lesnoy Zhurnal (Forestry Journal), no. 2 (April 1, 2022): 178–92. http://dx.doi.org/10.37482/0536-1036-2022-2-178-192.
Повний текст джерелаАнотація:
At the moment, there is a wide variety of materials for air filtration, however, it is necessary to develop new, more efficient and cost-effective materials. Numerous studies have shown that in order to obtain a highly effective filter material for fine air purification from particles of 0.1–0.5 μm, ultrafine and microfine glass fibers should be introduced into the composition. Glass fibers have a whole complex of unique properties: thermal, chemical and biological resistance, high specific surface area, filtering ability, strength and resistance to aggressive media. At the same time, glass fibers, unlike fibers of plant origin, do not have the ability to fibrillate, swell and bond formation. Therefore, a strong filter material requires a binder that provides the necessary technological strength while maintaining the specified filtering characteristics. The study of composite material based on mineral fiber was carried out, polyadherical complexes of aluminum, thermomechanical pulp (TMP), polyvinyl acetate (PVA) and polyethylene (PE) were used as binders. The main indicators are the tensile strength, capillary absorption, resistance to air flow and permeability coefficient. The novelty of this work lies in the application of TMP and PE as binders in the composite material based on glass fibers. The addition of a binder based on TMP to the composition is advisable in the range of 5–30 % of the fiber mass, for PE this range is 2–10 %. The studied composite material with the addition of PE as a binder has sufficient technological strength, a low coefficient of permeability and resistance to air flow. PE can be used as a promising binder for composite filter materials based on glass fibers for air purification.
50
Centrone, Mariangela, Maria De Santo, Isabella Nicotera, Cristina Labate, Marianna Ranieri, Annarita Di Mise, Maria Mola, et al. "Gi Protein Modulation of the Potassium Channel TASK-2 Mediates Vesicle Osmotic Swelling to Facilitate the Fusion of Aquaporin-2 Water Channel Containing Vesicles." Cells 7, no. 12 (December 19, 2018): 276. http://dx.doi.org/10.3390/cells7120276.
Повний текст джерелаАнотація:
Vesicle fusion is a fundamental cell biological process similar from yeasts to humans. For secretory vesicles, swelling is considered a step required for the expulsion of intravesicular content. Here this concept is revisited providing evidence that it may instead represent a general mechanism. We report the first example that non-secretory vesicles, committed to insert the Aquaporin-2 water channel into the plasma membrane, swell and this phenomenon is required for fusion to plasma membrane. Through an interdisciplinary approach, using atomic force microscope (AFM), a fluorescence-based assay of vesicle volume changes and NMR spectroscopy to measure water self-diffusion coefficient, we provide evidence that Gi protein modulation of potassium channel TASK-2 localized in AQP2 vesicles, is required for vesicle swelling. Estimated intravesicular K+ concentration in AQP2 vesicles, as measured by inductively coupled plasma mass spectrometry, was 5.3 mM, demonstrating the existence of an inwardly K+ chemical gradient likely generating an osmotic gradient causing vesicle swelling upon TASK-2 gating. Of note, abrogation of K+ gradient significantly impaired fusion between vesicles and plasma membrane. We conclude that vesicle swelling is a potentially important prerequisite for vesicle fusion to the plasma membrane and may be required also for other non-secretory vesicles, depicting a general mechanism for vesicle fusion.