scholarly journals A Novel Index (RI) to Evaluate the Relative Stability of Soils Using Ultrasonic Agitation

2021 ◽  
Vol 13 (8) ◽  
pp. 4229
Author(s):  
Fakher Abbas ◽  
Fang Lin ◽  
Zhaolong Zhu ◽  
Shaoshan An
Keyword(s):  
Relative Stability ◽  
Characteristic Curve ◽  
Geometric Mean ◽  
Relative Strength ◽  
Soil Stability ◽  
Dispersion Energy ◽  
Ultrasonic Agitation ◽  
Mean Weight Diameter ◽  
Change In Mean ◽  
Wet Sieving

As soil stability is a complex phenomenon, various methods and indexes were introduced to assess the strength of soils. Because of the limitations of different stability methods and indexes (including wet sieving-based), we aimed to presents a relative stability index (RI) that was based on the estimated components of the soil overall disruptive characteristic curve (SODC): (1) soil disruption constant (Ki, that is based upon dispersion energy of soils); (2) resulting change in mean weight diameter (ΔMWD). To evaluate the effectiveness and limitations of RI as well as to compare it with classical soil stability indexes of mean weight diameter (MWD) and geometric mean diameter (GMD). Ultrasonic agitation (UA) along with a wet sieving method (followed by dry sieving) was applied against four different soils named on the basis of sample location, Qingling soil (QL), Guanzhong soil (GZ), Ansai soil (AS), and Jingbian soil (JB). To evaluate the relative strength of soils at different applied energies (increase in sonication duration usually resulted in increased input energy and temperature of soil–water suspension), soils were subjected to six sonication durations (0, 30, 60, 120, 210, and 300 s) with a fixed (and exact) initial amplitude and temperature. Output energy was calculated based on the amplitude and temperature of the suspension, vessel, and system. The most abrupt and maximum disruption of soil aggregates was observed at a dispersion energy level of 0–200 J g−1. The MWD value of surface and subsurface ranged between 0.58 to 0.15 mm and 0.37 to 0.17 mm, respectively, while GMD was ranged from 0.14 to 0.33 mm overall. The results for MWD and GMD showed a similar trend. MWD and GMD showed more strong associations with physicochemical characteristics of soil than RI. A non-significant correlation was found between RI and MWD/GMD. Contrary to MWD and GMD, RI was significantly positively correlated with sand content; this finding indicated the influential role of sand in assessing the soil’s relative strength. The results indicated that JB soil possessed the least MWD and GMD but proved to be relatively stable because of having the highest RI value.

Characteristics and Stability of Soil Aggregates in Tea Plantation

2011 ◽  
Vol 343-344 ◽  
pp. 968-974
Author(s):  
Zi Cheng Zheng ◽  
Ting Xuan Li ◽  
Shu Qin He
Keyword(s):  
Soil Aggregates ◽  
Geometric Mean ◽  
Aggregate Stability ◽  
Stability Index ◽  
Soil Aggregate ◽  
Tea Plantation ◽  
Soil Aggregate Stability ◽  
Mean Weight Diameter ◽  
Eucalyptus Plantations ◽  
Wet Sieving

Soil aggregate stability as a key indicator of soil structure and erodibility to evaluate soil stability, is a product of interactions between soil environment, management practices, and land use patterns. The objective of this study was to analyze the distribution characteristics, characteristics of fractal features and stability of soil aggregates in tea plantations and eucalyptus plantations of Western Sichuan in China. The dry- and water-stable aggregate size distributions were determined by dry sieving and wet sieving methods. The results showed that soil structural properties in tea and eucalyptus plantations were similar. With increase in depth of soil layer, the aggregate stability of tea plantation soil became stronger. Comparative analysis of dry and wet sieving results showed that most of the aggregates in tea plantation soil were unstable. The soil aggregates >5mm and 0.5-0.25mm in size had higher stability, while those 2-1mm in size had lower stability. For tea plantation soil, the correlation coefficients between aggregate stability index and mean weight diameter, geometric mean diameter, fractal dimension were bigger under wet sieving than those under dry sieving. The results showed that aggregate stability index, mean weight diameter, geometric mean diameter, fractal dimension of water-stable aggregates could characterize soil aggregate stability in tea plantation ideally.

Bayesian approach to discriminant problems for count data with application to multilocus short tandem repeat dataset

2020 ◽  
Vol 19 (2) ◽  
Author(s):  
Koji Tsukuda ◽  
Shuhei Mano ◽  
Toshimichi Yamamoto
Keyword(s):  
Sample Size ◽  
Classification Accuracy ◽  
Tandem Repeats ◽  
Bayes Factor ◽  
Characteristic Curve ◽  
Geometric Mean ◽  
Previous Method ◽  
Threshold Adjustment ◽  
Two Populations ◽  
Short Tandem

AbstractShort Tandem Repeats (STRs) are a type of DNA polymorphism. This study considers discriminant analysis to determine the population of test individuals using an STR database containing the lengths of STRs observed at more than one locus. The discriminant method based on the Bayes factor is discussed and an improved method is proposed. The main issues are to develop a method that is relatively robust to sample size imbalance, identify a procedure to select loci, and treat the parameter in the prior distribution. A previous study achieved a classification accuracy of 0.748 for the g-mean (geometric mean of classification accuracies for two populations) and 0.867 for the AUC (area under the receiver operating characteristic curve). We improve the maximum values for the g-mean to 0.830 and the AUC to 0.935. Computer simulations indicate that the previous method is susceptible to sample size imbalance, whereas the proposed method is more robust while achieving almost identical classification accuracy. Furthermore, the results confirm that threshold adjustment is an effective countermeasure to sample size imbalance.

scholarly journals Severely imbalanced Big Data challenges: investigating data sampling approaches

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Tawfiq Hasanin ◽  
Taghi M. Khoshgoftaar ◽  
Joffrey L. Leevy ◽  
Richard A. Bauder
Keyword(s):  
Big Data ◽  
Operating Characteristic ◽  
Performance Metrics ◽  
Characteristic Curve ◽  
Geometric Mean ◽  
Class Imbalance ◽  
Random Undersampling ◽  
First Case ◽  
Negative Class

AbstractSevere class imbalance between majority and minority classes in Big Data can bias the predictive performance of Machine Learning algorithms toward the majority (negative) class. Where the minority (positive) class holds greater value than the majority (negative) class and the occurrence of false negatives incurs a greater penalty than false positives, the bias may lead to adverse consequences. Our paper incorporates two case studies, each utilizing three learners, six sampling approaches, two performance metrics, and five sampled distribution ratios, to uniquely investigate the effect of severe class imbalance on Big Data analytics. The learners (Gradient-Boosted Trees, Logistic Regression, Random Forest) were implemented within the Apache Spark framework. The first case study is based on a Medicare fraud detection dataset. The second case study, unlike the first, includes training data from one source (SlowlorisBig Dataset) and test data from a separate source (POST dataset). Results from the Medicare case study are not conclusive regarding the best sampling approach using Area Under the Receiver Operating Characteristic Curve and Geometric Mean performance metrics. However, it should be noted that the Random Undersampling approach performs adequately in the first case study. For the SlowlorisBig case study, Random Undersampling convincingly outperforms the other five sampling approaches (Random Oversampling, Synthetic Minority Over-sampling TEchnique, SMOTE-borderline1 , SMOTE-borderline2 , ADAptive SYNthetic) when measuring performance with Area Under the Receiver Operating Characteristic Curve and Geometric Mean metrics. Based on its classification performance in both case studies, Random Undersampling is the best choice as it results in models with a significantly smaller number of samples, thus reducing computational burden and training time.

Stabilization of Soil Aggregates in Relation to Soil Redistribution by Intensive Tillage on a Steep Hillslope

2014 ◽  
Vol 955-959 ◽  
pp. 3566-3571 ◽  
Author(s):  
Yong Wang ◽  
Zhuang Xiong ◽  
Wu Xian Yan ◽  
Yue Qun Qiu
Keyword(s):  
Soil Aggregates ◽  
Geometric Mean ◽  
Aggregate Stability ◽  
Aggregate Size ◽  
Soil Aggregate ◽  
Soil Aggregate Stability ◽  
Mean Weight Diameter ◽  
Tillage Operation ◽  
Sloping Land ◽  
The Impact

The objective of this study was to investigate soil aggregate stability within landscape on hillslopes by intensive tillage. Traditional tillage by consecutive hoeing was performed 5 and 20 times on steeply sloping land of the Sichuan Basin, China, by using the methods of simulated tillage to analyze the impact of long-term tillage on soil aggregates at different slope positions. The dry-sieved method was used to determine distribution of aggregate size in the different landscape positions, and mean weight diameter (MWD) and geometric mean diameter (GMD) as indices of soil aggregate stability. The different times of tillage resulted in different soil aggregate distributions. The results showed that the MWD and GMD values of aggregates were significantly decreased (p< 0.05) after 20-tillage operation, compared with pre-tillage operation. The differences in distributions of MWD and GMD demonstrate that the choice of the tillage times can be an important factor in changing soil aggregate stability and productivity in steeply sloping fields.

scholarly journals MACROAGGREGATION OF A PALEUDALF AFFECTED BY CAVITATION INTENSITY AND MANAGEMENT SYSTEMS WITH COVER PLANTS

2021 ◽  
Vol 15 (2) ◽  
pp. 283-302
Author(s):  
Érika Andressa Silva ◽  
Micael Stolben Mallmann ◽  
Monike Andrade Pereira ◽  
Sarah Severo Pons ◽  
Felipe Dalla –Zen Bertol ◽  
...  
Keyword(s):  
Geometric Mean ◽  
Aggregate Stability ◽  
Bare Soil ◽  
Management Systems ◽  
Hairy Vetch ◽  
Mean Diameter ◽  
Cavitation Intensity ◽  
Determination Methods ◽  
The Stability ◽  
Wet Sieving

Ultrasonic-based techniques allow the prediction of the energy required to break the aggregate and have been more commonly used to measure the stability of aggregates. Although they result in the same applied energy, certain combinations of time and power might correspond to different intensities of cavitation. Consequently, different responses in aggregation indexes can be obtained with different configurations of ultrasound techniques. Thus, this work was carried out to evaluate the effects of cavitation intensity in the distribution of aggregates of a Paleudalf under management systems with cover plants and to compare aggregate stability determination methods (ultrasound versus wet sieving). Aggregate samples of the BS (bare soil), OT (black oat + forage turnips) and OV (black oat + hairy vetch) treatments were exposed to ultrasonic irradiation in different combinations of potency and time: (U1) 74.5 W/4 s; (U2) 49.7 W/6 s; (U3) 74.5 W/10 s and (U4) 49.7 W/15 s. After each sonification, the samples were passed in the same set of sieves used in the standard method of wet sieving -WS (8.00 - 4.76, 4.76 - 2.00, 2.00 - 1.00, 1.00 - 0.25 and < 0.25 mm) and the geometric mean diameter (GMD) and mass-weighted mean diameter (WMD) were calculated. The amplitude of vibration exerted a greater influence on soil breakdown than the total energy applied. Compared to the ultrasound method, in the WS method observed higher percentage of retained aggregates in the size class 8-4.76 mm and, consequently, greater aggregation indexes GMD and WMD.

scholarly journals Impact of integrated nutrient management on some important physical and chemical attributes of soil vis-a-vis performance of bitter gourd

2017 ◽  
Vol 9 (1) ◽  
pp. 556-561
Author(s):  
Soumyabrata Chakraborty ◽  
Gyanendra Kumar
Keyword(s):  
Nutrient Management ◽  
Geometric Mean ◽  
Inorganic Fertilizer ◽  
Bitter Gourd ◽  
Mustard Oil ◽  
Central Research ◽  
Integrated Nutrient Management ◽  
Available Nitrogen ◽  
Mean Weight Diameter ◽  
Physical And Chemical

An experiment has been conducted under AICRP on Soil Test Crop Response (STCR) at the Central Research Farm (Gayeshpur), Bidhan Chandra Krishi Viswavidyalaya, West Bengal to find out the effect of integrated nutrient management in ArkaHarit variety of bitter gourd. The treatments contain different organic and inorganic fertilizer viz. Control (T1), NPK @ 90:60:60 kg/ha (T2), Vermicompost @ 12t/ha (T3), NPK+ Vermicompost @ 3t/ha (T4), FYM @ 25t/ha (T5), NPK+FYM @ 6.25t/ha (T6), Mustard oil cake (MOC) @ 7t/ha (T7), NPK+MOC @ 1.75t/ha (T8). Application of organic and inorganic sources in an integrated manner has resulted higher in yield, physical and chemical parameter such as seed yield (2815 kg/ha), aggregate ratio (0.69), mean weight diameter (0.593 mm), geometric mean weight diameter (0.679 mm), organic carbon (1.28 %), CEC (12.88 meq/100g), available nitrogen (208 kg/ha), phosphorus (62 kg/ha), potassium (167 kg/ha) in higher magnitude as compare to the single application of inorganic fertilizer. In maximum cases, the chemical parameters is highest in harvesting stage rather than other stage. Quality characters such as Vitamin A, C, crude fibre are nourished in favourable way due to integrated appli-cation of organic and inorganic fertilizers. Based on the performance, it was found that treatment combination of NPK+MOC @ 1.75t/ha (T8) was best among all treatments in most cases for yield, productivity and nutritional as-pects of ArkaHarit variety of bitter gourd.

scholarly journals Evaluation of Computer-Aided Nodule Assessment and Risk Yield (CANARY) in Korean patients for prediction of invasiveness of ground-glass opacity nodule

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253204
Author(s):  
Juyoung Lee ◽  
Brian Bartholmai ◽  
Tobias Peikert ◽  
Jaehee Chun ◽  
Hojin Kim ◽  
...  
Keyword(s):  
Binary Classification ◽  
Characteristic Curve ◽  
Geometric Mean ◽  
Ground Glass Opacity ◽  
Ground Glass ◽  
Invasive Adenocarcinoma ◽  
Entire Cohort ◽  
Korean Patients ◽  
Computed Tomography Images ◽  
Computer Aided

Differentiating the invasiveness of ground-glass nodules (GGN) is clinically important, and several institutions have attempted to develop their own solutions by using computed tomography images. The purpose of this study is to evaluate Computer-Aided Analysis of Risk Yield (CANARY), a validated virtual biopsy and risk-stratification machine-learning tool for lung adenocarcinomas, in a Korean patient population. To this end, a total of 380 GGNs from 360 patients who underwent pulmonary resection in a single institution were reviewed. Based on the Score Indicative of Lung Cancer Aggression (SILA), a quantitative indicator of CANARY analysis results, all of the GGNs were classified as “indolent” (atypical adenomatous hyperplasia, adenocarcinomas in situ, or minimally invasive adenocarcinoma) or “invasive” (invasive adenocarcinoma) and compared with the pathology reports. By considering the possibility of uneven class distribution, statistical analysis was performed on the 1) entire cohort and 2) randomly extracted six sets of class-balanced samples. For each trial, the optimal cutoff SILA was obtained from the receiver operating characteristic curve. The classification results were evaluated using several binary classification metrics. Of a total of 380 GGNs, the mean SILA for 65 (17.1%) indolent and 315 (82.9%) invasive lesions were 0.195±0.124 and 0.391±0.208 (p < 0.0001). The area under the curve (AUC) of each trial was 0.814 and 0.809, with an optimal threshold SILA of 0.229 for both. The macro F1-score and geometric mean were found to be 0.675 and 0.745 for the entire cohort, while both scored 0.741 in the class-equalized dataset. From these results, CANARY could be confirmed acceptable in classifying GGN for Korean patients after the cutoff SILA was calibrated. We found that adjusting the cutoff SILA is needed to use CANARY in other countries or races, and geometric mean could be more objective than F1-score or AUC in the binary classification of imbalanced data.

Adsorption of gases on 4A synthetic zeolite

1969 ◽  
Vol 47 (24) ◽  
pp. 4661-4670 ◽  
Author(s):  
R. J. Harper ◽  
G. R. Stifel ◽  
R. B. Anderson
Keyword(s):  
Characteristic Curve ◽  
Relative Strength ◽  
Principal Factor ◽  
Synthetic Zeolite ◽  
Freundlich Equation ◽  
Strong Adsorption ◽  
Equilibrium Data ◽  
Different Temperatures ◽  
Adsorption Of Gases ◽  
Permanent Gases

Equilibrium data are presented for the adsorption of permanent gases and C1 and C2 hydrocarbons on Linde 4A synthetic zeolite from 50 °C down to the boiling point of the adsorbate or to a temperature at which the rate was very slow. The Freundlich equation often fits isotherms accurately; however, these linear logarithmic plots seem to be only portions of a more general non-linear relationship. Generalized Polanyi plots did not yield a unique characteristic curve for individual adsorbates at different temperatures nor for groups of adsorbates; nevertheless, these plots are useful in estimating the relative strength of adsorption of gases. Ar, O2, CH4, and C2H6 were the least strongly adsorbed, followed in order of increasing strength by N2, CO, CO2, and C2H2. Ethylene was strongly but anomalously adsorbed. For the gases studied, the quadrupole moment seems to be the principal factor determining strong adsorption.

scholarly journals CHARACTERIZATION OF BIOGENIC, INTERMEDIATE AND PHYSICOGENIC SOIL AGGREGATES OF AREAS IN THE BRAZILIAN ATLANTIC FOREST

2017 ◽  
Vol 30 (1) ◽  
pp. 59-67 ◽  
Author(s):  
JÚLIO CÉSAR FEITOSA FERNANDES ◽  
◽  
MARCOS GERVASIO PEREIRA ◽  
EDUARDO CARVALHO DA SILVA NETO ◽  
THAÍS DE ANDRADE CORRÊA NETO
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Humic Substances ◽  
Soil Quality ◽  
Secondary Forest ◽  
Soil Aggregates ◽  
Geometric Mean ◽  
Mean Weight Diameter ◽  
Successional Stages ◽  
The Stability

ABSTRACT Aggregate formation and stability are related to soil quality, contributing significantly to the carbon storage and nutrient maintenance capacities of the soil. Soil aggregates are formed by two different process: physicogenic, related to moistening and drying cycles and input of organic matter; and biogenic, related to the action of macrofauna organisms and roots. The objective this work was to classify aggregates according to their formation process, quantify and compare organic carbon contents in humic substances and assess the stability of aggregates formed by different processes, in areas with different coverage in the Mid Paraiba Valley, Pinheiral, State of Rio de Janeiro, Brazil. Aggregated soil samples were collected at a depth of 0-10 cm, in a Cambisol (Cambissolo Háplico Tb Distrófico) under four plant covers: secondary forest in advanced (SFAS), medium (SFMS) and initial (SFIS) successional stages and managed mixed pasture (MMP). Aggregates were classified and identified into three morphological classes (physicogenic, biogenic and intermediate). The variables evaluated were mean weight diameter (MWD) and geometric mean diameter (GMD) of aggregates, chemical fractions of organic matter, total organic carbon (TOC) and humic substances: humin (C-HUM) humic acid (C-FAH) and fulvic acid (C-FAF). Biogenic aggregates were found in smaller quantities and showed higher TOC, C-HUM and C-FAH, compared to intermediate and physicogenic aggregates. Thus, biogenic aggregates have potential to be used as soil quality indicators for structured environments, which are able to maintain its intrinsic formation processes.

scholarly journals Spatial variability of aggregate stability in latosols under sugarcane

2009 ◽  
Vol 33 (2) ◽  
pp. 245-253 ◽  
Author(s):  
Zigomar Menezes de Souza ◽  
José Marques Júnior ◽  
Gener Tadeu Pereira ◽  
Carolina Maria Sánchez Sáenz
Keyword(s):  
Organic Matter ◽  
Spatial Variability ◽  
Management System ◽  
Geometric Mean ◽  
Aggregate Stability ◽  
Variation Coefficient ◽  
Mean Weight Diameter ◽  
Mean Diameter ◽  
Lower Variation ◽  
Red Latosol

The spatial variability of soils under a same management system is differentiated, as expressed in the properties. The spatial variability of aggregate stability of a eutrophic Red Latosol (ERL) and a dystrophic Red Latosol (DRL) under sugarcane was characterized. Samples were collected in a regular 10 m grid, in the layers 0.0-0.2 and 0.2-0.4 m, with 100 points per area, and the following properties were determined: geometric mean diameter (GMD) of aggregates, mean weight diameter (MWD) of aggregates, percent of aggregates in the > 2.0 mm class and organic matter (OM) content. The eutrophic Red Latosol (ERL) had a higher aggregate stability thn the dystrophic Red Latosol (DRL), which may be attributed to the higher clay and OM content and the gibbsitic mineralogy of this soil class. The differentiated evolution of the studied Oxisols explains the wider range and lower variation coefficient and variability, for all properties studied in the eutrophic Red Latosol.

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