scholarly journals Spatial Variability Analysis of Farmland Soil Infiltration Based on Model Parameters

2019 ◽  
Vol 136 ◽  
pp. 07021
Author(s):  
Qingdao Xin ◽  
Hemin Zhu ◽  
Yangren Wang ◽  
Xinrui Fan
Keyword(s):  
Water Movement ◽  
Direct Method ◽  
Correlation Coefficients ◽  
Simulation Method ◽  
Spatial Uncertainty ◽  
Model Parameters ◽  
Soil Infiltration ◽  
Infiltration Process ◽  
Farmland Soil ◽  
Significant Difference

Research on the variation of soil infiltration is helpful to analyze the mechanism of soil water movement in farmland. At the same time, soil infiltration characteristics affect the surface irrigation. Based on the field test data, this study simulated and analyzed the soil infiltration with three soil infiltration models (Kostiakov-Lewis model, Philip model and Horton model). The infiltration uncertainty of farmland soil are investigated, and proposed by using two random simulation methods (direct method and parameter mean method) of infiltration. The evaluated indicators are the interval size and its stability of cumulative infiltration amount changed with 95% confidence. The effects of different random simulations methods and three models on the infiltration process are compared and analyzed. Finally, the model and stochastic simulation method suitable for the infiltration characteristics of the farmland are determined. The results show that the correlation coefficients of the three models are all above 0.98, and there is no significant difference in fitting accuracy. In terms of the degree of spatial uncertainty (determined by standard deviation): direct method > parameter mean method, in which the combination of the Kostiakov-Lewis model and the parameter mean method have less uncertainty, and the combined simulation effect is better, it is more suitable for the simulation of soil infiltration at farmland scale.

scholarly journals Predicted Infiltration for Sodic/Saline Soils from Reclaimed Coastal Areas: Sensitivity to Model Parameters

2014 ◽  
Vol 2014 ◽  
pp. 1-12
Author(s):  
Dongdong Liu ◽  
Dongli She ◽  
Shuang’en Yu ◽  
Guangcheng Shao ◽  
Dan Chen
Keyword(s):  
Water Movement ◽  
Soil Surface ◽  
Coastal Areas ◽  
Model Parameters ◽  
Wetting Front ◽  
Sodic Soils ◽  
Infiltration Process ◽  
Infiltration Model ◽  
Soil Physical Quality ◽  
Cumulative Infiltration

This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline) and 1960 (Soil B, nonsaline) were used, with bulk densities of 1.4 or 1.5 g/cm3. A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent whenθ0was increased. Soil physical quality was described better by theSparameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

A Forecasting Method of Kostiakov Infiltration Model Parameters Based on Back-Propagation Model

2012 ◽  
Vol 610-613 ◽  
pp. 2899-2903
Author(s):  
Chong Wen Cao ◽  
Gui Sheng Fan
Keyword(s):  
Back Propagation ◽  
Influence Factors ◽  
Propagation Model ◽  
Water Infiltration ◽  
Physical Parameters ◽  
Model Parameters ◽  
Soil Infiltration ◽  
Infiltration Process ◽  
Infiltration Model ◽  
Bp Model

Based on test data of field soil water infiltration, Back-propagation (BP) model of predicting Kostiakov infiltration model parameters was established after analyzing the primary influence factors of water infiltration model parameters. The results indicate that BP model can reflect the non-linear relationship between the model parameters and the physical parameters of the soil; BP model is high accuracy for prediction soil infiltration model parameters. It can be referred as a new method to predict soil infiltration process using soil physical parameters.

scholarly journals Which LDL Value Should Clinicians Look at?

2021 ◽  
Author(s):  
Harshad Malve ◽  
Amit Asalkar
Keyword(s):  
Total Cholesterol ◽  
Direct Method ◽  
Tertiary Care ◽  
Colorimetric Method ◽  
Correlation Coefficients ◽  
Direct Methods ◽  
Estimation Methods ◽  
Care Hospital ◽  
Significant Difference ◽  
Indian Setting

Abstract Objectives LDL cholesterol is routinely estimated by the Friedewald formula to guide the treatment of dyslipidemia. However, Friedewald equation has certain limitations, especially with high triglyceride levels. Direct methods are available for LDL estimation but have received relatively little scrutiny in the Indian setting. This study was aimed at comparing the calculative and direct methods of LDL estimation in Indian hyperlipidemic patients. Materials and Methods In this observational study, data from 380 consecutive lipid profiles of patients visiting a tertiary care hospital in Mumbai were analyzed retrospectively. CHOD PAP method was used to estimate total cholesterol. Enzymatic colorimetric method was used to estimate triglycerides. Enzyme selective protection method was used to estimate HDL. Direct LDL was estimated by homogenous enzymatic colorimetric assay and very low-density lipoprotein was calculated, whereas Friedewald’s formula was used to derive calculated LDL. Results Total cholesterol values correlated positively with the LDL values measured by both methods. However, a statistically significant difference was noted between the correlation coefficients of both the methods. Triglyceride values correlated weakly with the LDL levels measured by both the methods. A weak negative correlation was observed with LDL by the calculated method, whereas a weak positive correlation existed between TG and LDL by the direct method. The difference between the correlation coefficients was statistically significant. Conclusion Both direct and calculated methods of LDL estimation have their limitations. A robust study with a larger sample size is needed to further investigate whether the differences in the different LDL estimation methods can translate to “clinical relevance” in the Indian setting.

scholarly journals Temporal and spatial infiltration characteristics of soil under acacia and pine plantations in the mountainous area of Van Don, Quang Ninh, Vietnam

2019 ◽  
Vol 11 (2) ◽  
pp. 51-64
Author(s):  
Xuan Dung BUI ◽  
Thi Hoai Thu VU ◽  
Thi My Linh NGUYEN ◽  
Takashi GOMI
Keyword(s):  
Ground Cover ◽  
Infiltration Rate ◽  
Mountainous Area ◽  
Soil Infiltration ◽  
Infiltration Process ◽  
Double Ring ◽  
Pine Tree ◽  
Dye Tracer ◽  
Significant Difference ◽  
The Hill

To determine the soil infiltration characteristics of pine and acacia plantations, we used a double-ring infiltrometer in 15 different locations of up-hill, mid-hill and down-hill part in each kind of plantation from June to August, 2018. The spatial infiltration characteristics of the soil at three plots (with no tree, with acacia tree and with pine tree) was determined by dye tracer method. The factors having an impact to the infiltration process were also analyzed. The main findings include: (1) The soil infiltration rate under both pine and acacia plantation decreased over time and it was the highest in the bottom of the hill and the lowest in the middle of the hill. The infiltration rate and the total infiltrated water in one hour at the acacia plantation were higher than ones at the pine plantation. However, statistical significant difference was only found for stable infiltration rate between two plantations; (2) The area and the depth of infiltrated water were the highest at the plot without trees, smaller at the soil of acacia plot and smallest at the soil of pine plot. All spatial infiltration rates were within the findings of previous studies; (3) The result indicated that soil with high ground cover has high infiltration rate. Để xác định đặc điểm thấm nước của đất dưới rừng trồng Thông và Keo, vòng đôi đo tốc độ thấm đã được sử dụng để đo ở sườn trên, sườn giữa và sườn dưới (5 lần/ ví trí) cho mỗi loại hình rừng từ tháng 6-8/2018. Trong khi, thuốc nhuộm được sử dụng để kiểm tra đặc điểm thấm nước của đất theo không gian trên 3 ô (ô không có cây, ô trồng Keo và ô trồng Thông). Các yếu tố ảnh hưởng đến đặc điểm thấm nước cũng được phân tích. Kết quả chính thu được: (1) Tốc độ thấm ở cả hai loại rừng giảm dần theo thời gian và cao nhất ở sườn dưới,  nhỏ nhất ở sườn giữa. Cả tốc độ thấm và tổng lượng nước thấm trong một giờ của rừng keo đều cao hơn so với rừng Thông. Tuy nhiên, chỉ có tốc độ thấm ổn định là khác biệt có ý nghĩa thống kê; (2) Diện tích và độ sâu nước thấm xuống đất cao nhất ở ô không có cây, nhỏ hơn ở ô trồng Keo và nhỏ nhất ở ô trồng Thông; (3) Độ che phủ thực vật càng cao thì lượng nước thấm càng lớn.

scholarly journals Antifungal Activity of Propyl Disulfide from Neem (Azadirachta indica) in Vapor and Agar Diffusion Assays against Anthracnose Pathogens (Colletotrichum gloeosporioides and Colletotrichum acutatum) in Mango Fruit

2021 ◽  
Vol 9 (4) ◽  
pp. 839
Author(s):  
Muhammad Rafiullah Khan ◽  
Vanee Chonhenchob ◽  
Chongxing Huang ◽  
Panitee Suwanamornlert
Keyword(s):  
Antifungal Activity ◽  
Mycelial Growth ◽  
Colletotrichum Gloeosporioides ◽  
Colletotrichum Acutatum ◽  
Model Parameters ◽  
Pathogenicity Test ◽  
Agar Diffusion ◽  
Wide Range ◽  
Significant Difference ◽  
Diffusion Assay

Microorganisms causing anthracnose diseases have a medium to a high level of resistance to the existing fungicides. This study aimed to investigate neem plant extract (propyl disulfide, PD) as an alternative to the current fungicides against mango’s anthracnose. Microorganisms were isolated from decayed mango and identified as Colletotrichum gloeosporioides and Colletotrichum acutatum. Next, a pathogenicity test was conducted and after fulfilling Koch’s postulates, fungi were reisolated from these symptomatic fruits and we thus obtained pure cultures. Then, different concentrations of PD were used against these fungi in vapor and agar diffusion assays. Ethanol and distilled water were served as control treatments. PD significantly (p ≤ 0.05) inhibited more of the mycelial growth of these fungi than both controls. The antifungal activity of PD increased with increasing concentrations. The vapor diffusion assay was more effective in inhibiting the mycelial growth of these fungi than the agar diffusion assay. A good fit (R2, 0.950) of the experimental data in the Gompertz growth model and a significant difference in the model parameters, i.e., lag phase (λ), stationary phase (A) and mycelial growth rate, further showed the antifungal efficacy of PD. Therefore, PD could be the best antimicrobial compound against a wide range of microorganisms.

scholarly journals Study on Friction in Automotive Shock Absorbers Part 1: Friction Simulation Using a Dynamic Friction Model in the Contact Zone of an FEM Model

Vehicles ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 212-232
Author(s):  
Ludwig Herzog ◽  
Klaus Augsburg
Keyword(s):  
Ride Comfort ◽  
Viscous Friction ◽  
Simulation Method ◽  
Friction Model ◽  
Model Parameters ◽  
Dynamic Friction ◽  
Friction Modeling ◽  
Shock Absorbers ◽  
Operation Conditions ◽  
Wide Range

The important change in the transition from partial to high automation is that a vehicle can drive autonomously, without active human involvement. This fact increases the current requirements regarding ride comfort and dictates new challenges for automotive shock absorbers. There exist two common types of automotive shock absorber with two friction types: The intended viscous friction dissipates the chassis vibrations, while the unwanted solid body friction is generated by the rubbing of the damper’s seals and guides during actuation. The latter so-called static friction impairs ride comfort and demands appropriate friction modeling for the control of adaptive or active suspension systems. In this article, a simulation approach is introduced to model damper friction based on the most friction-relevant parameters. Since damper friction is highly dependent on geometry, which can vary widely, three-dimensional (3D) structural FEM is used to determine the deformations of the damper parts resulting from mounting and varying operation conditions. In the respective contact zones, a dynamic friction model is applied and parameterized based on the single friction point measurements. Subsequent to the parameterization of the overall friction model with geometry data, operation conditions, material properties and friction model parameters, single friction point simulations are performed, analyzed and validated against single friction point measurements. It is shown that this simulation method allows for friction prediction with high accuracy. Consequently, its application enables a wide range of parameters relevant to damper friction to be investigated with significantly increased development efficiency.

A prospective randomized study to assess the efficacy of post-operative nasal medication after endonasal surgery

1995 ◽  
Vol 109 (7) ◽  
pp. 618-621 ◽  
Author(s):  
Paul D. R. Spraggs ◽  
Marcelle Macnamara ◽  
Theo Joseph
Keyword(s):  
Randomized Study ◽  
Correlation Coefficients ◽  
Control Group ◽  
Time Intervals ◽  
Treatment Groups ◽  
Ephedrine Hydrochloride ◽  
Patent Airway ◽  
Significant Difference ◽  
Blood Clots ◽  
Betamethasone Sodium Phosphate

AbstractPost-operative nasal medications are commonly used following routine septal or turbinate surgery but their efficacy in removing blood clots, improving the sensation of a patent airway and promoting healing are unknown. This prospective randomized trial of patients undergoing septal and/or turbinate surgery assessed the efficacy of three commonly used nasal medicines, 0.5 per cent ephedrine hydrochloride nasal drops, betamethasone sodium phosphate (Betnosol®) nose drops and alkaline nasal douches, in producing the sensation of a patent airway in the 14 days following surgery. Ninety-seven patients were randomized into the three treatment groups and a control group who received no nasal medication. Patients assessed their nasal patency by means of a visual analogue scale (VAS) and any complications of treatment were recorded. Statistical analysis of the 76 complete sets of results using the Mann-Whitney U-test showed that there was a significant difference in the distribution of all of the treatments for each of the time intervals (p<0.05). Glass rank biserial correlation coefficients were all small (rg<0.085) but the most significant differences were between ephedrine and the control group at two hours, two, seven and 10 days (0.02, 0.054, 0.057, 0.085 respectively), alkaline nasal douches being most significant at four and 14 days (0.06 and 0.0722 respectively).

scholarly journals A study of Soil Invertebrates community in a Date - Palm plantation in Baghdad, Iraq

2016 ◽  
Vol 13 (1) ◽  
pp. 1-6
Author(s):  
Baghdad Science Journal
Keyword(s):  
Organic Matter ◽  
Direct Method ◽  
Chemical Properties ◽  
Essential Elements ◽  
Soil Samples ◽  
Land Snails ◽  
Soil Invertebrates ◽  
Individual Number ◽  
Significant Difference ◽  
Physical And Chemical

Soil invertebrates community an important role as part of essential food chain and responsible for the decomposition in the soil, helps soil aeration , nutrients recycling and increase agricultural production by providing the essential elements necessary for photosynthesis and energy flow in ecosystems.The aim of the present study was to investigate the soil invertebrates community in one of the date palms plantation in Aljaderia district South of Baghdad, , and their relationships with some physical and chemical properties of the soil , as Five randomly distributed replicates of soil samples were collected monthly. Invertebrates samples were sorted from the soil with two methods, direct method to isolate large invertebrates and indirectly to isolate small invertebrates using wet funnel method. The study also included the determination of physical and chemical factors of the soil (Temperature, Salinity, pH, Organic matter, Humidity, In addition to the soil texture).Monthly fluctuations in physical and chemical characteristics of the soil and the total invertebrates community study site were determined. Significant correlations the of the invertebrates community and each of temperature, organic matter, and humidity were observed. The study revealed that the temperature of the soil ranged between 5 to 25 C0 , The salinity concentration ranged between 1.1-1.9 ‰, The pH values ranged between 7.3 to 7.8 and the percentage of soil moisture ranged between 15 - 25% , Soil samples were composed of 44.6 % Clay, 19.7% Silt and 35.5% Sand.A total of 4625 individuals of soil invertebrates belonging to 16 taxa were sorted , within which the adult and larval insects were the most abundant, and from them 1283 individuals were sorted , represented 28% of the total numbers, followed by Isopoda , which 1030 individuals of them were sorted, In addition to Nematode, Oligochaetes Annelids family Enchytraeidae, and Earthworms family Lumbricida, Species of Chilopoda, Diplopoda, mites, land snails and slugs. The highest total individual number were recorded recorded durim moderate temperature months, February, March and April amounted to 838, 801 and 813 individuals, respectively.A significant correlation was mated between total number of soil invertebrates and each of temperature, organic matter and humidity. The significant difference in means was calculated according to LSD test.

scholarly journals An Investigation on Serum Mineral Levels of Healthy Norduz and Hair Goats Raised in Semi-Intensive Conditions

2020 ◽  
Vol 8 (8) ◽  
pp. 1795-1802
Author(s):  
Ayşe Özge Demir ◽  
Ferda Karakuş ◽  
Suna Akkol
Keyword(s):  
Atomic Absorption ◽  
Absorption Spectroscopy ◽  
Atomic Absorption Spectroscopy ◽  
Age Groups ◽  
Correlation Coefficients ◽  
Serum Minerals ◽  
Significant Difference ◽  
Positive Correlations ◽  
Mineral Levels ◽  
Ppm Level

The aim of this study was to determine the some serum minerals and their interactions between in 2, 3 and 4 years-old healthy Norduz (n=45) and Hair (n=31) goats raised in semi-intensive conditions. Mineral levels were determined with Atomic absorption spectroscopy (AAS) in ppm level. Results were calculated as Fe 1.578±0.088 and 1.379±0.095 mmol/L, Cu 1.300±0.067 and 1.303±0.080 mg/L, Zn 0.972±0.029 and 0.937±0.029 mg/L, K 4.574±0.091 and 2.102±0.074 mmol/L, Mg 2.089±0.057 and 4.670±0.098 mmol/L, Mn 2.163±0.152 and 2.215±0.198 mg/L, Pb 0.078±0.005 and 0.087±0.006 mg/L for Norduz and Hair goats, respectively. While the differences in the mineral levels of hair goats were not significant, significant differences has been found between the age groups in terms of K, F and Pb in Norduz goats. In addition, while there was no statistically significant difference between 3-year-old goats, statistically significant differences hs been found for Fe and 2-year-old goats K and Mg in 4-year-old goats. Moreover, with respect to correlation coefficients, positive correlations were obtained both between K-Mg at Norduz goats and between Fe-Cu, Fe-K, Fe-Mg, K-Mg at Hair goats in all years-old groups.

scholarly journals Water footprint analysis of temporary crops produced in São Carlos (SP), Brazil

RBRH ◽  
2020 ◽  
Vol 25 ◽  
Author(s):  
Alan Reis ◽  
Alessandra Campos dos Santos ◽  
Jamil Alexandre Ayach Anache ◽  
Eduardo Mario Mendiondo ◽  
Edson Cezar Wendland
Keyword(s):  
Crop Yields ◽  
Water Footprint ◽  
Statistical Tests ◽  
Correlation Coefficients ◽  
Mean Values ◽  
Monotonic Trend ◽  
Significant Difference ◽  
Footprint Analysis ◽  
Global Mean ◽  
Total Average

ABSTRACT This paper aims to evaluate the water footprint (WF) of temporary crops produced in the municipality of São Carlos, Brazil, between 2004 and 2017. The WF calculation was developed following the Water Footprint Network approach (WFN) and using CROPWAT model. The results were compared with the world averages and other studies that analyzed the same crops. We applied statistical tests to verify data behavior over the years and calculated correlation coefficients between WF components and crop yields. The results indicated low values of total WF for sugarcane (total average of 166.2 m3 ton-1) and tomato (total average of 97.2 m3 ton-1), while rice (total average of 5212.4 m3 ton-1) and groundnut (total average of 3865.8 m3 ton-1) showed the opposite. In general, WF components do not follow a monotonic trend, a normal distribution can be assumed and there is a statistically significant difference when comparing our findings with global mean values. These results ratify the importance of local WF studies, especially in Brazil, considering its importance in global agricultural market and the respective use of water resources.

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