scholarly journals Assessment of Surface Runoff for Tank Watershed in Tamil Nadu Using Hydrologic Modeling

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Marykutty Abraham ◽  
Riya Ann Mathew
Keyword(s):  
Water Balance ◽  
Regression Model ◽  
Tamil Nadu ◽  
Large Population ◽  
Annual Rainfall ◽  
Balance Study ◽  
Average Annual Runoff ◽  
Significant Difference ◽  
Simple Regression Model ◽  
Nrcs Model

Providing safe and wholesome water in sufficient quantity on a sustainable basis remains elusive for large population especially in semiarid regions and hence water balance estimation is vital to assess water availability in a watershed. The water balance study is formulated to assess the runoff that can be harvested for effective utilization. The study area is Urapakkam watershed with a chain of 3 tanks having an aerial extent of 4.576 km2 with hard rock formation underneath and thus has limited scope for groundwater recharge. Hence surface water is the main water source in this area. Runoff computed for the watershed using USDA-NRCS model varied from 94.95 mm to 2324.34 mm and the corresponding rainfall varied from 575.7 mm to 3608.0 mm, respectively. A simple regression model was developed for the watershed to compute runoff from annual rainfall. Average annual runoff estimated for the watershed was around 37% of the rainfall for the study period from 2000-01 to 2013-14. Statistical analysis and test of significance for runoff obtained by NRCS model and regression model did not show any significant difference thus proving that regression model is efficient in runoff computation for ungauged basins. The volume of water accessible for fifty percent dependable flow year is obtained as 2.46 MCM and even if 50% of it can be effectively harnessed the water available in the watershed is 1.23 MCM. The water demand of the area is estimated as 0.148 MCM for domestic purpose and 0.171 MCM for irrigation purpose, which is much lower than the available runoff that can be harnessed from the watershed. Thus there is scope to harvest 1.23 MCM of water which is more than the demand of the watershed. The study reveals that it is feasible to harvest and manage water effectively if its availability and demand are computed accurately.

Prediction of hydraulic load for urban storm control of a municipal WWT plant

1998 ◽  
Vol 37 (12) ◽  
pp. 363-370 ◽  
Author(s):  
Jacob Carstensen ◽  
Marinus K. Nielsen ◽  
Helle Strandbæk
Keyword(s):  
Regression Model ◽  
Flow Model ◽  
Measured Data ◽  
Box Model ◽  
Significant Difference ◽  
Simple Regression Model ◽  
Hydraulic Load ◽  
Dynamical Flow ◽  
Simple Regression ◽  
Better Than

Three different methodologies are assessed which provide predictions of the hydraulic load to the treatment plant one hour ahead. The three models represent three different levels of complexity ranging from a simple regression model over an adaptive grey-box model to a complex hydrological and full dynamical wave model. The simple regression model is estimated as a transfer function model of rainfall intensity to influent flow. It also provides a model for the base flow. The grey-box model is a state space model which incorporates adaptation to the dry weather flow as well as the rainfall runoff. The full dynamical flow model is a distributed deterministic model with many parameters, which has been calibrated based on extensive measurement campaigns in the sewer system. The three models are compared by the ability to predict the hydraulic load one hour ahead. Five rain events in a test period are used for evaluating the three different methods. The predictions are compared to the actual measured flow at the plant one hour later. The results show that the simple regression model and the adaptive grey-box model which are identified and estimated on measured data perform significantly better than the hydrological and full dynamical flow model which is not identifiable and needs calibration by hand. For frontal rains no significant difference in the prediction performance between the simple regression model and the adaptive grey-box model is observed. This is due to a rather uniform distribution of frontal rains. A single convective rain justifies the adaptivity of the grey-box model for non-uniformly distributed rain, i.e. the predictions of the grey-box model were significantly better than the predictions of the simple regression model for this rain event. In general, models for model-based predictive control should be kept simple and identifiable from measured data.

Water Balance of an Australian Subtropical Rainforest at Altitude: the Ecological and Physiological Significance of Intercepted Cloud and Fog

1997 ◽  
Vol 45 (2) ◽  
pp. 311 ◽  
Author(s):  
Lindsay B. Hutley ◽  
David Doley ◽  
David J. Yates ◽  
Arthorn Boonsaner
Keyword(s):  
Water Balance ◽  
Vegetation Type ◽  
Rain Gauge ◽  
Annual Rainfall ◽  
Balance Study ◽  
Term Survival ◽  
Tree Transpiration ◽  
Fog Deposition ◽  
Dry Seasons

A water balance study of a small subtropical rainforest catchment (10 ha, 1000 m altitude) was conducted at Gambubal State Forest, near the headwaters of the Condamine River, 200 km south-west of Brisbane, south-eastern Queensland. Mean annual rainfall of the site is approximately 1125 mm, but is variable and often less than 900 mm. Tree transpiration rates are low and depletion of the large soil moisture reserves enables extraction for lengthy periods of time, permitting survival during extended dry seasons (May–November). Fog deposition to the forest provides the equivalent of an additional 40% of rainfall to the site as measured using a conventional rain gauge. A frequently wet canopy results in reduced transpiration rates and direct foliar absorption of moisture alleviates water deficits of the upper crown leaves and branches during the dry season. These features of this vegetation type may enable long-term survival at what could be considered to be a marginal rainforest site.

scholarly journals Rainfall, evapotranspiration and rainfall deficit trend in Alor Setar, Malaysia

2017 ◽  
Vol 13 (4-1) ◽  
pp. 400-404
Author(s):  
Aimi Athirah Ahmad ◽  
Fadhilah Yusof ◽  
Muhamad Radzali Mispan ◽  
Hasliana Kamaruddin
Keyword(s):  
Water Balance ◽  
Trend Analysis ◽  
Water Cycle ◽  
Potential Evapotranspiration ◽  
Irrigation System ◽  
Annual Rainfall ◽  
Agricultural Systems ◽  
Balance Study ◽  
Rainfall Deficit ◽  
Increasing Trends

Rainfall and potential evapotranspiration are important variables in water balance study. Rainfall data were obtained from Malaysian Meteorological Department while estimates of potential evapotranspiration were calculated using Penman-Monteith method. Trend analysis of monthly and annual rainfall, potential evapotranspiration and rainfall deficit are essential to manage irrigation system in agricultural systems. This is because changes in trend of these parameters may affect the water cycle and ecosystem. Annual and monthly values of these variables were analysed from 1980-2009. Results indicated  increasing trends of 16.2 mm yr-1 and 3.01 mm yr-1 for both annual rainfall and potential evapotranspiration, respectively. Consequently, these trends resulted in annual rainfall deficit of 1.69 mm per year. 

scholarly journals A Retrospective Experience of Helicobacter pylori Histology in a Large Sample of Subjects in Northern Italy

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 650
Author(s):  
Davide Giuseppe Ribaldone ◽  
Carlo Zurlo ◽  
Sharmila Fagoonee ◽  
Chiara Rosso ◽  
Angelo Armandi ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Large Population ◽  
Population Data ◽  
Signet Ring Cell ◽  
Current Data ◽  
Low Grade ◽  
Gastric Cardia Adenocarcinoma ◽  
Significant Difference ◽  
H Pylori ◽  
The Impact

Updated data about the prevalence of Helicobacter pylori (H. pylori) and its correlation with histological results are scarce. The aim of our study was to provide current data on the impact of H. pylori in a third-level endoscopy service. We performed a large, retrospective study analyzing the results of all histological samples of gastroscopy from the year 2019. In total, 1512 subjects were included. The prevalence of H. pylori was 16.8%. A significant difference between the prevalence in subjects born in Italy and those from eastern Europe, south America, or Africa was found (p < 0.0001, p = 0.006, and p = 0.0006, respectively). An association was found between H. pylori and active superficial gastritis (p < 0.0001). Current H. pylori and/or a previous finding of H. pylori was related to antral atrophy (p < 0.0001). Fifteen patients had low-grade dysplasia. There were no statistically significant associations with current or past H. pylori infection. One patient presented gastric cardia adenocarcinoma with regular gastric mucosa. One patient, H. pylori positive, was diagnosed with gastric signet ring cell adenocarcinoma in a setting of diffuse atrophy, without metaplasia.. Our study provides updated, solid (biopsy diagnosis and large population) data on the prevalence of H. pylori infection in a representative region of southern Europe.

scholarly journals Primary tumor surgery improves survival in non-metastatic primary urethral carcinoma patients: a large population-based investigation

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jie Wu ◽  
Yu-Chen Wang ◽  
Wen-Jie Luo ◽  
Bo-Dai ◽  
Ding-Wei Ye ◽  
...  
Keyword(s):  
Regression Model ◽  
Competing Risks ◽  
Primary Tumor ◽  
Cox Regression ◽  
Radical Surgery ◽  
Large Population ◽  
Local Therapy ◽  
Primary Site ◽  
Urethral Carcinoma ◽  
The Impact

Abstract Background Primary urethral carcinoma (PUC) is a rare genitourinary malignancy with a relatively poor prognosis. The aim of this study was to examine the impact of surgery on survival of patients diagnosed with PUC. Methods A total of 1544 PUC patients diagnosed between 2004 and 2016 were identified based on the SEER database. The Kaplan-Meier estimate and the Fine and Gray competing risks analysis were performed to assess overall survival (OS) and cancer-specific mortality (CSM). The multivariate Cox regression model and competing risks regression model were used to identify independent risk factors of OS and cancer-specific survival (CSS). Results The 5-yr OS was significantly better in patients who received either local therapy (39.8%) or radical surgery (44.7%) compared to patients receiving no surgery of the primary site (21.5%) (p < 0.001). Both local therapy and radical surgery were each independently associated with decreased CSM, with predicted 5-yr cumulative incidence of 45.4 and 43.3%, respectively, compared to 64.7% for patients receiving no surgery of the primary site (p < 0.001). Multivariate analyses demonstrated that primary site surgery was independently associated with better OS (local therapy, p = 0.037; radical surgery, p < 0.001) and decreased CSM (p = 0.003). Similar results were noted regardless of age, sex, T stage, N stage, and AJCC prognostic groups based on subgroup analysis. However, patients with M1 disease who underwent primary site surgery did not exhibit any survival benefit. Conclusion Surgery for the primary tumor conferred a survival advantage in non-metastatic PUC patients.

scholarly journals Empiric use of anticoagulation in hospitalized patients with COVID-19: a propensity score-matched study of risks and benefits

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Bo Yu ◽  
Victor Perez Gutierrez ◽  
Alex Carlos ◽  
Gregory Hoge ◽  
Anjana Pillai ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Propensity Score ◽  
Propensity Score Matching ◽  
Major Bleeding ◽  
Risk Estimation ◽  
Large Population ◽  
Invasive Mechanical Ventilation ◽  
Bleeding Risk ◽  
Hospitalized Patients ◽  
Significant Difference

Abstract Background Hospitalized patients with COVID-19 demonstrate a higher risk of developing thromboembolism. Anticoagulation (AC) has been proposed for high-risk patients, even without confirmed thromboembolism. However, benefits and risks of AC are not well assessed due to insufficient clinical data. We performed a retrospective analysis of outcomes from AC in a large population of COVID-19 patients. Methods We retrospectively reviewed 1189 patients hospitalized for COVID-19 between March 5 and May 15, 2020, with primary outcomes of mortality, invasive mechanical ventilation, and major bleeding. Patients who received therapeutic AC for known indications were excluded. Propensity score matching of baseline characteristics and admission parameters was performed to minimize bias between cohorts. Results The analysis cohort included 973 patients. Forty-four patients who received therapeutic AC for confirmed thromboembolic events and atrial fibrillation were excluded. After propensity score matching, 133 patients received empiric therapeutic AC while 215 received low dose prophylactic AC. Overall, there was no difference in the rate of invasive mechanical ventilation (73.7% versus 65.6%, p = 0.133) or mortality (60.2% versus 60.9%, p = 0.885). However, among patients requiring invasive mechanical ventilation, empiric therapeutic AC was an independent predictor of lower mortality (hazard ratio [HR] 0.476, 95% confidence interval [CI] 0.345–0.657, p < 0.001) with longer median survival (14 days vs 8 days, p < 0.001), but these associations were not observed in the overall cohort (p = 0.063). Additionally, no significant difference in mortality was found between patients receiving empiric therapeutic AC versus prophylactic AC in various subgroups with different D-dimer level cutoffs. Patients who received therapeutic AC showed a higher incidence of major bleeding (13.8% vs 3.9%, p < 0.001). Furthermore, patients with a HAS-BLED score of ≥2 had a higher risk of mortality (HR 1.482, 95% CI 1.110–1.980, p = 0.008), while those with a score of ≥3 had a higher risk of major bleeding (Odds ratio: 1.883, CI: 1.114–3.729, p = 0.016). Conclusion Empiric use of therapeutic AC conferred survival benefit to patients requiring invasive mechanical ventilation, but did not show benefit in non-critically ill patients hospitalized for COVID-19. Careful bleeding risk estimation should be pursued before considering escalation of AC intensity.

scholarly journals A Threat of Farmers’ Suicide and the Opportunity in Organic Farming for Sustainable Agricultural Development in India

2019 ◽  
Vol 11 (8) ◽  
pp. 2400 ◽  
Author(s):  
Karthikeyan Mariappan ◽  
Deyi Zhou
Keyword(s):  
Organic Farming ◽  
Tamil Nadu ◽  
Agricultural Development ◽  
Small Scale ◽  
Conventional Farming ◽  
Wide Range ◽  
Significant Difference ◽  
Small Scale Farmers ◽  
The Cost ◽  
Input Cost

Agriculture is the main sources of income for humans. Likewise, agriculture is the backbone of the Indian economy. In India, Tamil Nadu regional state has a wide range of possibilities to produce all varieties of organic products due to its diverse agro-climatic condition. This research aimed to identify the economics and efficiency of organic farming, and the possibilities to reduce farmers’ suicides in the Tamil Nadu region through the organic agriculture concept. The emphasis was on farmers, producers, researchers, and marketers entering the sustainable economy through organic farming by reducing input cost and high profit in cultivation. A survey was conducted to gather data. One way analysis of variance (ANOVA) has been used to test the hypothesis regards the cost and profit of rice production. The results showed that there was a significant difference in profitability between organic and conventional farming methods. It is very transparent that organic farming is the leading concept of sustainable agricultural development with better organic manures that can improve soil fertility, better yield, less input cost and better return than conventional farming. The study suggests that by reducing the cost of cultivation and get a marginal return through organic farming method to poor and small scale farmers will reduce socio-economic problems such as farmers’ suicides in the future of Indian agriculture.

Face Gear Width Prediction Using the DOE Method

2008 ◽  
Vol 130 (10) ◽  
Author(s):  
Michèle Guingand ◽  
Didier Remond ◽  
Jean-Pierre de Vaujany
Keyword(s):  
Regression Model ◽  
Simple Formula ◽  
Design Parameters ◽  
Face Gear ◽  
Main Design ◽  
Gear Design ◽  
Simple Regression Model ◽  
Numerical Tool ◽  
Influential Parameters ◽  
Simple Regression

This paper deals with face gear design. The goal is to propose a simple formula for predicting the width of the wheel as a function of the main design parameters. A specific software was used to achieve this goal. This numerical tool is able to simulate the geometry and the quasistatic loaded behavior of a face gear. The statistical method used for analyzing the influence of data is described: The design of experiments leads to a simple regression model taking into account the influential parameters and their couplings. In the last part of this paper, the results of the formulas are compared to those of the software and an optimal design is proposed based on the regression model.

Harvesting and Threshing Methods on Seed Quality of Dhaincha (Sesbania aculeata)

2021 ◽  
Author(s):  
P. Masilamani ◽  
T. Eevera ◽  
T. Ramesh ◽  
S. Venkatesan
Keyword(s):  
Tamil Nadu ◽  
Seed Quality ◽  
Block Design ◽  
Mechanical Damage ◽  
Shoot Length ◽  
Seedling Vigour ◽  
Root And Shoot Length ◽  
Significant Difference ◽  
Combine Harvester ◽  
The Impact

Background: The present investigation is an attempt to study the effect of different harvesting and threshing methods on germination and seedling vigour of dhaincha. The use of a combine harvester to harvest dhaincha will be an effective alternative method that has not been widely tried. However, work on different methods of harvesting and threshing of dhaincha is limited. Hence, a study was conducted to evaluate the impact of various harvesting and threshing methods on germination and seedling vigour of dhaincha. Methods: This study was conducted at Anbil Dharmalingam Agricultural College and Research Institute, TNAU, Tiruchirappalli, Tamil Nadu. The dhaincha crop was harvested and threshed using four different methods viz., manual harvesting and manual threshing, manual harvesting and threshing by tractor treading, manual harvesting and mechanical threshing and harvesting and threshing by combine harvester. The resultant seeds were tested for mechanical damage and germination potential. The experiment was laid in completely randomized block design. Germination was tested by roll towel method using 100 seeds in four replications. Germination percentage, root and shoot length were measured in seven days after sowing from ten randomly selected seedlings in each replication. For the estimation of dry matter production, ten seedlings were selected at random and kept in a hot air oven maintained at 85oC for 24 hours after measuring their root and shoot length and vigour index was calculated. Mechanical damage to seeds was observed by ferric chloride test. Seed recovery per cent was calculated based on the 100 kgs of dhaincha seeds were cleaned and graded treatment wise using cleaner cum grader and the seeds retained on the bottom sieve were weighed and expressed as per cent of total quantity of seed. Result: The results revealed that the significant difference was found among the different harvesting and threshing methods. The seeds harvested and threshed by manual method recorded 85 per cent germination followed by seeds harvested manually and threshed by mechanical threshing (84 per cent) and seeds harvested manually and threshed by tractor treading (80.5 per cent). The lowest germination of 80.0 per cent was recorded by combine harvesting. From this study, it could be inferred that combine harvester is a modern method for harvesting of dhaincha that saves time and labour when compared to all other methods.

scholarly journals Modelling monthly runoff generation processes following land use changes: groundwater–surface runoff interactions

2004 ◽  
Vol 8 (5) ◽  
pp. 903-922 ◽  
Author(s):  
M. Bari ◽  
K. R. J. Smettem
Keyword(s):  
Land Use ◽  
Water Balance ◽  
Surface Runoff ◽  
Land Use Changes ◽  
Annual Rainfall ◽  
Rainfall Runoff ◽  
Runoff Generation ◽  
Mean Annual Rainfall ◽  
Monthly Runoff ◽  
Stream Bed

Abstract. A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, "Ernies" (control, fully forested) and "Lemon" (54% cleared) are in a zone of mean annual rainfall of 725 mm, while "Salmon" (control, fully forested) and "Wights" (100% cleared) are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i) an upper zone unsaturated store, (ii) a transient stream zone store, (ii) a lower zone unsaturated store and (iv) a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and predicted monthly hydrographs. The observed and predicted monthly runoff for all catchments matched well with coefficients of determination (R2) ranging from 0.68 to 0.87. Predictions were relatively poor for: (i) the Ernies catchment (lowest rainfall, forested), and (ii) months with very high flows. Overall, the predicted mean annual streamflow was within ±8% of the observed values. Keywords: monthly streamflow, land use change, conceptual model, data-based approach, groundwater

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