scholarly journals Sensitivity and regression analysis of acoustic parameters for determining physical properties of frozen fine sand with ultrasonic test

2020 ◽  
Vol 54 (1) ◽  
pp. qjegh2020-021
Author(s):  
Ji-wei Zhang ◽  
Julian Murton ◽  
Shu-jie Liu ◽  
Li-li Sui ◽  
Song Zhang ◽  
...  
Keyword(s):  
Physical Properties ◽  
Water Content ◽  
Wave Velocity ◽  
Field Measurements ◽  
Fine Sand ◽  
Dominant Frequency ◽  
Acoustic Parameters ◽  
Supplementary Material ◽  
The Difference ◽  
The Relationship

Determining the development of artificial frozen walls by present methods is challenging where substantial seepage occurs because fixed monitoring points only indicate physical properties in small areas. Here we use ultrasonic acoustic methods to determine the physical properties between two freezing pipes during freezing. Sensitivity analysis indicates that wave velocity is sensitive to physical properties, and the sensitivity rank is water content > temperature > density. The attenuation coefficient has a low sensitivity to physical parameters, whereas dominant frequency is sensitive to temperature and water content but insensitive to density. Wave velocity increases with temperature and density in a quadratic relationship, and with water content in a linear relationship. Dominant frequency increases with temperature and water content in a quadratic relationship. A multiple regression model of wave velocity and dominant frequency established by stepwise regression can be used to predict the relationship between wave velocity and temperature of frozen fine sand in different areas where the soil properties are similar to those reported here. Wave velocity and dominant frequency measured in the laboratory can be used to predict the relationship between acoustic parameters and temperature in field conditions after curve move based on the first data point from field measurements. The procedure of curve moving involves calculating the difference in value of the first data point between laboratory and field measurements at the same temperature level, and then moving the predicted curve of the laboratory test upward or downward according to the difference.Supplementary material: Experimental datasets are available at https://doi.org/10.6084/m9.figshare.12268970

scholarly journals Remotely Sensed Water Limitation in Vegetation: Insights from an Experiment with Unmanned Aerial Vehicles (UAVs)

2019 ◽  
Author(s):  
Kelly Easterday ◽  
Chippie Kislik ◽  
Tod E. Dawson ◽  
Sean Hogan ◽  
Maggi Kelly
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Water Content ◽  
Water Deficit ◽  
Water Status ◽  
Field Measurements ◽  
Flying Height ◽  
Plant Water ◽  
Spectral Indices ◽  
Aerial Vehicles ◽  
The Relationship

Unmanned aerial vehicles (UAVs) equipped with multispectral sensors present an opportunity to monitor vegetation with on-demand high spatial and temporal resolution. In this study, we use multispectral imagery from quadcopter UAVs to monitor the progression of a water manipulation experiment on a common shrub, Baccharis pilularis (coyote brush), at the Blue Oak Ranch Reserve (BORR) near San Jose, California. We recorded multispectral data from the plants at several altitudes with nearly hourly intervals to explore the relationship between two common spectral indices, NDVI and NDRE, and plant water content and water potential, as physiological metrics of plant water status, across a gradient of water deficit. An examination of the spatial and temporal thresholds at which water limitations were most detectable revealed that the best separation between levels of water deficit were at higher resolution (lower flying height), and in the morning (NDVI) and early morning (NDRE). We found that both measures were able to identify moisture deficit in plants and distinguish them from control and watered plants; however, NDVI was better able to distinguish between treatments than NDRE and was more positively correlated with field measurements of plant water content than NDRE. Finally, we explored how relationships between spectral indices and water status changed when the imagery was scaled to courser resolutions provided by satellite-based imagery (PlanetScope) and found that PlanetScope data was able to capture the overall trend in treatments but was not able to capture subtle changes in water content. These kinds of experiments that evaluate the relationship between direct field measurements and UAV camera sensitivity are needed to enable translation of field-based physiology measurements to landscape or regional scales.

scholarly journals The Secrets of Beautiful Hair: Why is it Flexible and Elastic?

Cosmetics ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 40 ◽  
Author(s):  
Mikako Ezure ◽  
Noriyuki Tanji ◽  
Yukari Nishita ◽  
Takashi Mizooku ◽  
Shinobu Nagase ◽  
...  
Keyword(s):  
Physical Properties ◽  
Layered Structure ◽  
Outer Layer ◽  
New Technology ◽  
Selective Reduction ◽  
Cell Distribution ◽  
Cortical Cells ◽  
The Difference ◽  
The Relationship ◽  
Hair Surface

Beautiful hair, so called “SHINAYAKA” hair in Japanese, has a good appearance not only when stationary but also when in motion, and it is a highly desirable hair condition for Japanese consumers. We investigated such SHINAYAKA hair, which was selected by sensory evaluation, for the relationship between physical properties, such as flexibility and elasticity, and hair structure. It has already been reported that human hair cortical cells have two types, similar to wool: the ortho-like cortex and the para-like cortex. Microscopic observation revealed that the ortho-like cortex is distributed in the outer layer of the hair (near the hair surface) and the para-like cortex exists in the inner layer (near the center of the fiber). This cell distribution, a concentric double-layered structure, was deemed to be a characteristic of SHINAYAKA hair. Furthermore, analysis of physical properties showed the difference between the elasticity of the outer layer and inner layer, and that this difference was bigger in SHINAYAKA hair compared to other hair. This phenomenon was observed not only in Japanese hair, but also in Caucasian hair. In addition, we have developed a new technology for creating “SHINAYAKA” hair by treatment with succinic acid. Inflexible and inelastic hair can be changed by this treatment, and its flexibility and elasticity improve by selective reduction of stiffness of the outer layer.

Density-dependent calibration of multisensor capacitance probes in coarse soil

2015 ◽  
Vol 95 (4) ◽  
pp. 331-336 ◽  
Author(s):  
Julie D. Zettl ◽  
Mingbin Huang ◽  
S. Lee Barbour ◽  
Bing C. Si
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Field Measurements ◽  
Water Dynamics ◽  
Laboratory Measurements ◽  
Calibration Equation ◽  
Density Dependent ◽  
Capacitance Probe ◽  
The Relationship ◽  
Coarse Soil

Zettl, J. D., Huang, M., Barbour, S. L. and Si, B. C. 2015. Density-dependent calibration of multisensor capacitance probes in coarse soil. Can. J. Soil Sci. 95: 331–336. Coarse-textured reconstructed soils are utilized extensively in the reclamation of mining waste. Accurate and continuous sensing of soil water content is required to understand soil water dynamics and evaluate the hydraulic characteristics of these soils. The EnviroSCAN (Sentek Pty. Ltd, Australia) is a semi-permanent multisensor capacitance probe (MCP) capable of continuous measurement of volumetric water content (θv) and has been used to monitor reclamation soil cover performance. Calibration of these probes is required to improve the accuracy of field measurements. In this study, field and laboratory measurements were undertaken over a range of water contents and bulk densities to refine the relationship between θvand scaled frequency (SF) measured by the MCP. The manufacturer's calibration equation tended to underestimate θvunder wet conditions (θv>0.35 cm3cm–3). Our experimental data showed that bulk density (ρb) did affect the MCP calibration and consequently a new calibration equation that includes the effect of ρbis developed using laboratory measurements and validated using field measurements. This equation provided the highest degree of correlation and the smallest standard deviation of prediction to measured values of θvfor laboratory and field measurements, respectively. This calibration improves the application of the EnviroSCAN for coarse-textured soils such as those utilized in this study.

scholarly journals On the Relationship of Thermodynamic and Physical Properties of Polymers With Ice Adhesion

1985 ◽  
Vol 6 ◽  
pp. 146-149 ◽  
Author(s):  
H. Murase ◽  
K. Nanishi
Keyword(s):  
Physical Properties ◽  
Adhesive Strength ◽  
Polymer System ◽  
Work Of Adhesion ◽  
Polymer Composition ◽  
Coating Materials ◽  
The Difference ◽  
Relationship Of ◽  
The Relationship ◽  
Ice Adhesion

The purpose of this work is to study the relationship of energetic and physical properties of polymetric materials with ice adhesion, and to develop the material to prevent ice adhesion. From various parameters of water and ice, dispersion and hydrogen bond contribution of surface free energy of ice were calculated. Using these values and that of contact angle formed between Ice and polymer in the air and also in paraffin, work of adhesion W-πe and W were determined respectively. The difference W-(W-πe ) has made it possible to evaluate the effect of surface pressure n on ice adhesion. On the other hand, actual adhesive strength of ice was measured. Some correlations between theoretical and observed values were found. Further, visco-elastic properties of polymers below icing temperature and temperature dependence of strain in the ice/polymer system were investigated. The results showed some characteristics of polymers which are related to molecular mobility at lower temperature, are effective in reducing the adhesive strength to ice. Numerous attempts were made to develop coating materials to prevent ice adhesion. A composite polymer composition, which has peculiar ingredients and structure, was proposed and found to provide the ability for the lowest ice adhesion. Ice preventive mechanism of the film was discussed.

scholarly journals Remotely Sensed Water Limitation in Vegetation: Insights from an Experiment with Unmanned Aerial Vehicles (UAVs)

2019 ◽  
Vol 11 (16) ◽  
pp. 1853 ◽  
Author(s):  
Kelly Easterday ◽  
Chippie Kislik ◽  
Todd Dawson ◽  
Sean Hogan ◽  
Maggi Kelly
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Water Content ◽  
Water Deficit ◽  
Water Status ◽  
Field Measurements ◽  
Leaf Water Content ◽  
Multispectral Imagery ◽  
Spectral Indices ◽  
Aerial Vehicles ◽  
The Relationship

Unmanned aerial vehicles (UAVs) equipped with multispectral sensors present an opportunity to monitor vegetation with on-demand high spatial and temporal resolution. In this study we use multispectral imagery from quadcopter UAVs to monitor the progression of a water manipulation experiment on a common shrub, Baccharis pilularis (coyote brush) at the Blue Oak Ranch Reserve (BORR) ~20 km east of San Jose, California. We recorded multispectral imagery at several altitudes with nearly hourly intervals to explore the relationship between two common spectral indices, NDVI (normalized difference vegetation index) and NDRE (normalized difference red edge index), leaf water content and water potential as physiological metrics of plant water status, across a gradient of water deficit. An examination of the spatial and temporal thresholds at which water limitations were most detectable revealed that the best separation between levels of water deficit were at higher resolution (lower flying height), and in the morning (NDVI) and early morning (NDRE). We found that both measures were able to identify moisture deficit across treatments; however, NDVI was better able to distinguish between treatments than NDRE and was more positively correlated with field measurements of leaf water content. Finally, we explored how relationships between spectral indices and water status changed when the imagery was scaled to courser resolutions provided by satellite-based imagery (PlanetScope).We found that PlanetScope data was able to capture the overall trend in treatments but unable to capture subtle changes in water content. These kinds of experiments that evaluate the relationship between direct field measurements and UAV camera sensitivity are needed to enable translation of field-based physiology measurements to landscape or regional scales.

Effect of Rainfall Infiltration on Loess Pitted Courtyard Cave Dwellings Stability

2012 ◽  
Vol 430-432 ◽  
pp. 1992-1995 ◽  
Author(s):  
Jia Ming Han ◽  
San Qing Su
Keyword(s):  
Water Content ◽  
Safety Factor ◽  
Triaxial Test ◽  
Field Measurements ◽  
Surrounding Rock ◽  
Rainfall Infiltration ◽  
Mechanical Parameter ◽  
Different Depths ◽  
Definition Of ◽  
The Relationship

Baishe villagers have inhabited loess pitted courtyard cave dwelling for hundreds of years in Sanyuan County of China.The sizes of local cave dwellings are mastered by field measurements, and variational regularity is summarized of average annual and monthly rainfall. By the soil routine and triaxial test, the physical and mechanical parameter is acquired with loess samples in different water content.At the same time, based on the literature datas, the relationship is established between rainfall and water content. Then, the definition of safety factor is given for loess cave dwellings in different depths, making use of the expressions of the surrounding rock loop stress and the Mohr - Coulomb intensity criterion. In the end,the variation of stability of loess cave dwelling could be analysed under different rainfall.

Study on Poisson Ratio of Soil-Rock Mixture in Low Strain

2011 ◽  
Vol 90-93 ◽  
pp. 1921-1925 ◽  
Author(s):  
Xian Min Zhang ◽  
Yao Zhi Lv ◽  
Yi Ming Zhao ◽  
Yu Hui Zhang ◽  
Zhi Liao
Keyword(s):  
Water Content ◽  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Poisson Ratio ◽  
Nonlinear Models ◽  
Absolute Error ◽  
Longitudinal Wave Velocity ◽  
Mixture Samples ◽  
The Relationship

Longitudinal wave velocity and shear wave velocity of two kinds of the soil-rock mixture samples with different stone content and water content are tested. Then the poisson ratio of the samples in Low Strain can be calculated with the method of wave velocity testing. Analyzing the relationship between poisson ratio, water content and stone content, the dualistic nonlinear models of poisson ratio, water content and stone content are established. The result of verifying is shown that the absolute error of poisson ratio is less than 0.01 and the relative error is less than 2%. The models not only can show the relationship between poisson ratio, water content and stone content but can provide the reference when changing the Rayleigh wave velocity to shear wave velocity each other.

scholarly journals Effects of Land Cover and Atmospheric Input on Nutrient Budget in Subtropical Mountainous Rivers, Northeastern Taiwan

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2800
Author(s):  
Chung-Te Chang ◽  
Yu-Ting Shih ◽  
Li-Chin Lee ◽  
Jun-Yi Lee ◽  
Tsung-Yu Lee ◽  
...  
Keyword(s):  
Land Cover ◽  
Agricultural Land ◽  
Field Measurements ◽  
Nutrient Budget ◽  
Minor Role ◽  
Atmospheric Input ◽  
The Difference ◽  
Reservoir Watershed ◽  
One Year ◽  
The Relationship

The nutrient budget, the difference between the nutrient output via stream and input via precipitation, can provide insights into how environmental processes affect forested ecosystem biogeochemistry. In this study, field measurements of the nutrient budgets—including Na+, Cl−, K+, Mg2+, Ca2+, NO3−, and SO42−—of 19 sites were conducted in Feitsui Reservoir Watershed (FRW) of northeastern Taiwan. A series of power-law regressions were developed to establish the relationship of the nutrient budget to the discharge, nutrient input, agricultural land cover, and slope. The result show that the weekly nutrient budget is significantly affected by agricultural land and input via precipitation (R2 of regression models ≥ 0.90), yet the relationship varies among different nutrient elements. The agricultural land cover is the major factor, while the input via precipitation plays a relatively minor role in the budget of Cl−, Mg2+, Ca2+, and SO42−. These nutrients could be provisioned abundantly from the system, and thus the input via precipitation is not the predominant controlling factor. By contrast, the Na+ and K+ inputs via precipitation are indispensable for accurately estimating the riverine exports. Because weathering is a limited source of K+, the roles of agricultural activities and input via precipitation are likely decisive for transport. Besides, the NO3− budget reveals a strong interplay between the atmospheric input and agricultural land, as expected. Because the nutrient budget model of NO3− is strongly improved, the R2 changes from 0.34 to 0.99 when a larger coefficient in exponent term (10.2) for agricultural land cover (showing that NO3− export is strongly hydrologically controlled) and precipitation input are included. Our analysis is based on one year of data, so extrapolating the result to a long-term period should be done with caution, as there could be substantial inter-annual variation. The nutrient budget approach provides a preliminary assessment to evaluate the impacts of agriculture and atmospheric deposition on nutrient export, which can provide a precursory reference for watershed management for improving water quality and mitigating eutrophication.

Analysis of Pitted Courtyard Cave Dwellings Stability in Baishe Village when Rainfall Infiltration

2011 ◽  
Vol 250-253 ◽  
pp. 2468-2472 ◽  
Author(s):  
Jia Ming Han ◽  
San Qing Su
Keyword(s):  
Water Content ◽  
Field Measurements ◽  
Strength Criterion ◽  
Annual Rainfall ◽  
Rock Stress ◽  
Average Annual Rainfall ◽  
The Stability ◽  
The Relationship ◽  
Water Contents

Pitted courtyard cave dwellings were used as a long-term living form in Baishe village. After field measurements, the size of local pitted courtyards and cave dwellings had been mastered, and the variation of average annual rainfall and monthly rainfall had been analyzed. By the experiment, the changes of physical and mechanical indexes could be showed with different water contents. At the same time, based on the literature, the relationship could be established between rainfall and water content. Basis in the expression of room rock stress and the Mohr-Coulomb strength criterion, the stability of the cave dwellings could be analyzed under different water contents, and the definition could be found of safety factor of loess cave. Then, the stability variation of loess cave dwelling could be obtained in different rainfall, and the evaluation results are given.

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