scholarly journals Operational strategy to monitor coastal erosion in tropical areas

2017 ◽  
Vol 8 (3) ◽  
pp. 135-143 ◽  
Author(s):  
Basanta Kumar Jena ◽  
D Sathish Kumar ◽  
Karunakar Kintada
Keyword(s):  
Coastal Erosion ◽  
Tamil Nadu ◽  
Surf Zone ◽  
Numerical Models ◽  
Coastal Communities ◽  
Operational Strategies ◽  
Spatial And Temporal Scales ◽  
Optimal Monitoring ◽  
Set Up ◽  
Generic Set

Assessment of coastal erosion is of high significance given the fact that the coastal communities are densely populated areas and have an influence on the food cycle directly and indirectly. Continuous monitoring is essential part of the work for any intervention to be carried out owing to the seasonal and inter-annual variability. The article discusses the measurement criteria and stages in an operational plan for a monitoring exercise, preparation and execution. Erosion can be due to a variety of natural and anthropogenic causes in general. The topic draws attention of both researchers and coastal communities equally. This article explains the need for operational strategies for an optimal monitoring of coastal erosion. Demonstration of such methodology was presented with a case study at a micro-tidal sandy beach located in Tamil Nadu. A generic set up for a plan boundary to measure met-ocean parameters over a time and spatial extent covering the beach and near-shore sediment regime, shore face and surf zone hydrodynamics is discussed. For a detailed understanding, numerical models are set up against the measurements to have a feel of the spatial variability. Validation was taken up extensively and the predictions were used to enhance the measurements in spatial and temporal scales, advantages with such setup.

scholarly journals LONGSHORE CURRENTS DUE TO SURF ZONE BARRIER

1978 ◽  
Vol 1 (16) ◽  
pp. 44
Author(s):  
R. Bettess ◽  
C.A. Fleming ◽  
J.C. Heinrich ◽  
O.C. Zienkiewicz ◽  
D.I. Austin
Keyword(s):  
Sediment Transport ◽  
Stream Function ◽  
Water Intake ◽  
Surf Zone ◽  
Numerical Models ◽  
Cooling Water ◽  
Radiation Stress ◽  
Longshore Currents ◽  
Set Up ◽  
Incident Waves

We consider a straight coastline exposed to large regular waves, of typical wave length, 100 m amplitude 1.6 m, and period 12 sec. The radiation stress gradients in the extensive (up to 2 km wide) surf zone cause set up and long-shore currents. Despite these currents, the beach is known to be fairly stable. If now a cooling water intake basin is introduced on the coast, it is required to determine first whether the wave induced currents in the vicinity of the basin will affect the circulation of cooling water and second, whether sediment transport will occur, leading to a dredging requirement for the basin. An extensive programme of physical model testing and numerical studies is being undertaken, in order to answer the above questions, and this paper will survey the progress made to date. At the 15th Coastal Engineering Conference a paper on the application of a mathematical model to the prediction of dredging properties inside a cooling water intake basin was 9 presented by Fleming and Hunt, which described the first stage of this work . - In that paper a sediment transport model was combined interactively with numerical models of wave refraction, wave diffraction, long shore currents and circulation currents. The last of these numerical models was used to evaluate the current patterns due to the interruption of the continuity of the longshore currents, together with the cooling water flows in the vicinity of the basin. In this paper we describe the development of more sophisticated numerical models for the first three stages of the process. An understanding of the process of longshore current and set up creation, depends on the concept of radiation stress, introduced by Longuet-Higgins and Stewart,12'13' ' in a series of papers. A number of workers have since used the radiation stress to determine coastline phenomena, and we now describe a few of the relevant papers, without any attempt at a comprehensive survey. Bowen 5'6 considered a straight coastline with parallel contours, and determined near shore circulation patterns, using a stream function formulation of the shallow water equations, for normally incident waves, with a sinusoidal coastwise variation in wave amplitude. He used a finite difference method to solve for the stream function. Longuet-Higgins10'11 criticized Bowen's use of a constant mixing length (horizontal) viscosity, and introduced a viscosity which varied directly with the distance from the shore, in his one dimensional analytical model for obliquely incident waves. He was able to obtain analytically longshore velocity profiles, which he plotted for a range of viscosities.

M. V. Nadkarni. Farmer's Movements in India. New Delhi: Allied Publishers Pvt. Ltd., 1987.237 pp.,Price: (hardbound edition) Rupees (Indian) 100.00.

1988 ◽  
Vol 27 (3) ◽  
pp. 333-335
Author(s):  
Khwaja Sarmad
Keyword(s):  
Tamil Nadu ◽  
Rural Poverty ◽  
Price Policy ◽  
New Delhi ◽  
Root Cause ◽  
The Subject ◽  
The Rich ◽  
Land Holdings ◽  
Set Up ◽  
Agricultural Price

This book is a comprehensive analysis of farmers' movements in India with a focus on the movements in Tamil Nadu, Maharashtra, Punjab and Karnatka. It examines the economic, social and political aspects of the farmers' struggle for a better deal within regional and national perspectives and evaluates the potential impact of these struggles on economic development in general, and on rural development, in particular. In a most competent way the author has presented the current state of the debate on the subject. He deals exhaustively with the subject of agricultural price policy and argues against the proposition that favourable price-setting for farm products is adequate to alleviate rural poverty. A better way to tackle this problem is to improve the per capita output in the rural sector, since the root cause of the problem is not unfavourable terms of trade but the increasing proportion of land holdings, which are economically not viable. Agricultural price policy is analyzed within the context of class relations, which enables to establish a link between the economic and political demands of the farmers. This analysis leads the author to conclude, that in contrast with the peasants' movements in India, which helped to break up the feudal agrarian set-up, the recent farmers' movements, with a few exceptions, have little revolutionary content. Their leadership has been appropriated by the rich landowners, who have transformed the movements into a lobby for advancing their own interests, within the existing power structure, to the neglect of the poorer peasantry.

scholarly journals The Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study—Defining a Threshold for Non-Cycloplegic Myopia Prevalence in Children

2021 ◽  
Vol 10 (6) ◽  
pp. 1215
Author(s):  
Aparna Gopalakrishnan ◽  
Jameel Rizwana Hussaindeen ◽  
Viswanathan Sivaraman ◽  
Meenakshi Swaminathan ◽  
Yee Ling Wong ◽  
...  
Keyword(s):  
Open Field ◽  
Tamil Nadu ◽  
Mean Difference ◽  
School Vision ◽  
Elite School ◽  
Prevalence Estimates ◽  
The Mean ◽  
Clinically Significant ◽  
Set Up ◽  
Definition Of

The aim of this study was to investigate the agreement between cycloplegic and non-cycloplegic autorefraction with an open-field auto refractor in a school vision screening set up, and to define a threshold for myopia that agrees with the standard cycloplegic refraction threshold. The study was conducted as part of the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) study, which investigated the prevalence, incidence, and risk factors for myopia among children in South India. Children from two schools aged 5 to 15 years, with no ocular abnormalities and whose parents gave informed consent for cycloplegic refraction were included in the study. All the children underwent visual acuity assessment (Pocket Vision Screener, Elite school of Optometry, India), followed by non-cycloplegic and cycloplegic (1% tropicamide) open-field autorefraction (Grand Seiko, WAM-5500). A total of 387 children were included in the study, of whom 201 were boys. The mean (SD) age of the children was 12.2 (±2.1) years. Overall, the mean difference between cycloplegic and non-cycloplegic spherical equivalent (SE) open-field autorefraction measures was 0.34 D (limits of agreement (LOA), 1.06 D to −0.38 D). For myopes, the mean difference between cycloplegic and non-cycloplegic SE was 0.13 D (LOA, 0.63D to −0.36D). The prevalence of myopia was 12% (95% CI, 8% to 15%) using the threshold of cycloplegic SE ≤ −0.50 D, and was 14% (95% CI, 11% to 17%) with SE ≤ −0.50 D using non-cycloplegic refraction. When myopia was defined as SE of ≤−0.75 D under non-cycloplegic conditions, there was no difference between cycloplegic and non-cycloplegic open-field autorefraction prevalence estimates (12%; 95% CI, 8% to 15%; p = 1.00). Overall, non-cycloplegic refraction underestimates hyperopia and overestimates myopia; but for subjects with myopia, this difference is minimal and not clinically significant. A threshold of SE ≤ −0.75 D agrees well for the estimation of myopia prevalence among children when using non-cycloplegic refraction and is comparable with the standard definition of cycloplegic myopic refraction of SE ≤ −0.50 D.

Leakage Flow Investigations on a Through-Wall Crack Related to Thermal Fatigue of Nuclear Power Plant Piping

2017 ◽  
Author(s):  
Stefan Schmid ◽  
Rudi Kulenovic ◽  
Eckart Laurien
Keyword(s):  
Experimental Data ◽  
Nuclear Power ◽  
Numerical Models ◽  
Measurement Techniques ◽  
Experimental Investigations ◽  
Leakage Flow ◽  
Test Rig ◽  
Reduced Pressure ◽  
Flow Rates ◽  
Set Up

For the validation of empirical models to calculate leakage flow rates in through-wall cracks of piping, reliable experimental data are essential. In this context, the Leakage Flow (LF) test rig was built up at the IKE for measurements of leakage flow rates with reduced pressure (maximum 1 MPA) and temperature (maximum 170 °C) compared to real plant conditions. The design of the test rig enables experimental investigations of through-wall cracks with different geometries and orientations by means of circular blank sheets with integrated cracks which are installed in the tubular test section of the test rig. In the paper, the experimental LF set-up and used measurement techniques are explained in detail. Furthermore, first leakage flow measurement results for one through-wall crack geometry and different imposed fluid pressures at ambient temperature conditions are presented and discussed. As an additional aspect the experimental data are used for the determination of the flow resistance of the investigated leak channel. Finally, the experimental results are compared with numerical results of WinLeck calculations to prove specifically in WinLeck implemented numerical models.

Effect of Digital Pedagogy in Ierventions in Rural Areas

2021 ◽  
pp. 227-240
Author(s):  
Sona Ahuja ◽  
Diksha Yadav
Keyword(s):  
Academic Achievement ◽  
Rural Areas ◽  
Online Teaching ◽  
Tamil Nadu ◽  
Learning Experience ◽  
Learning System ◽  
School Students ◽  
Digital Pedagogy ◽  
Set Up ◽  
Teaching Learning

The present study provides a description of the model of interactive digital pedagogy for remote areas and its impact on pedagogical satisfaction and academic achievement of students. This pedagogical intervention was designed to enrich and supplement the teaching-learning experience in remote and underprivileged schools through the use of technology. An interactive online teaching-learning system was set-up using a digital pedagogy. 150 school students and 80 prospective teachers from three higher secondary schools of Madhya Pradesh and Tamil Nadu participated in the study. Pedagogical satisfaction and academic achievement of the school students who studied in this set-up were examined. The results revealed that active learning, technological competence and learner autonomy were enhanced in an online environment when compared to an offline environment.

Assessment of Radius of Investigation of Pressure Transient Analysis in Highly Heterogeneous Reservoirs

2021 ◽  
Author(s):  
Murat Zeybek ◽  
Lei Jiang ◽  
Hadrien Dumont
Keyword(s):  
Transient Analysis ◽  
Numerical Models ◽  
Heterogeneous Systems ◽  
Layered Systems ◽  
Pressure Transient ◽  
Heterogeneous Reservoirs ◽  
Geological Features ◽  
Heterogeneous Formations ◽  
Set Up ◽  
New Generation

Abstract The radius of investigation (ROI) of pressure transient analyses has been traditionally assessed using analytical formulations with basic reservoir parameters for homogenous systems. Numerous studies aimed to improve ROI formulations to incorporate all reservoir and testing parameters such as gauge resolution and rate for more accurate ROI assessments. However, new generation wireline formation testers aim to improve deep transient tests with significant developments in gauge resolution and increasing rate. Challenges still remain in heterogeneous formations such as shaly sands and carbonate reservoirs. In this study, detailed conceptual high-resolution numerical models are set up, including comprehensive reservoir and measurement parameters, to investigate more realistic ROI assessments in layered heterogeneous systems without and with hydraulic communication. Several conceptual examples are presented in layered systems with permeability contrasts. In addition, deviation from infinite-acting radial flow (IAFR) and pressure propagation in highly heterogeneous layered systems are investigated to detect the presence of geological features, including closed boundary systems and the presence of a fault in the proximity of wellbore.

scholarly journals Wavelet-based spatial comparison technique for analysing and evaluating two-dimensional geophysical model fields

2012 ◽  
Vol 5 (1) ◽  
pp. 223-230 ◽  
Author(s):  
S. Saux Picart ◽  
M. Butenschön ◽  
J. D. Shutler
Keyword(s):  
Satellite Data ◽  
Fishery Management ◽  
Numerical Models ◽  
Spatial Scales ◽  
Marine Ecosystem ◽  
Original Method ◽  
Precipitation Forecast ◽  
Spatial And Temporal Scales ◽  
Geographical Patterns ◽  
Marine Ecosystem Model

Abstract. Complex numerical models of the Earth's environment, based around 3-D or 4-D time and space domains are routinely used for applications including climate predictions, weather forecasts, fishery management and environmental impact assessments. Quantitatively assessing the ability of these models to accurately reproduce geographical patterns at a range of spatial and temporal scales has always been a difficult problem to address. However, this is crucial if we are to rely on these models for decision making. Satellite data are potentially the only observational dataset able to cover the large spatial domains analysed by many types of geophysical models. Consequently optical wavelength satellite data is beginning to be used to evaluate model hindcast fields of terrestrial and marine environments. However, these satellite data invariably contain regions of occluded or missing data due to clouds, further complicating or impacting on any comparisons with the model. This work builds on a published methodology, that evaluates precipitation forecast using radar observations based on predefined absolute thresholds. It allows model skill to be evaluated at a range of spatial scales and rain intensities. Here we extend the original method to allow its generic application to a range of continuous and discontinuous geophysical data fields, and therefore allowing its use with optical satellite data. This is achieved through two major improvements to the original method: (i) all thresholds are determined based on the statistical distribution of the input data, so no a priori knowledge about the model fields being analysed is required and (ii) occluded data can be analysed without impacting on the metric results. The method can be used to assess a model's ability to simulate geographical patterns over a range of spatial scales. We illustrate how the method provides a compact and concise way of visualising the degree of agreement between spatial features in two datasets. The application of the new method, its handling of bias and occlusion and the advantages of the novel method are demonstrated through the analysis of model fields from a marine ecosystem model.

scholarly journals FIELD MEASUREMENTS AND MODELLING OF NEARSHORE CURRENTS AT A HIGH-ENERGY GEOLOGICALLY-CONSTRAINED BEACH

2020 ◽  
pp. 18
Author(s):  
Arthur Mouragues ◽  
Philippe Bonneton ◽  
Bruno Castelle ◽  
Vincent Marieu
Keyword(s):  
Surf Zone ◽  
Low Frequency ◽  
Field Measurements ◽  
High Energy ◽  
Oblique Wave ◽  
Wave Forcing ◽  
Circulation Patterns ◽  
Wave Conditions ◽  
Nearshore Currents ◽  
Set Up

We present field measurements of nearshore currents at a high-energy mesotidal beach with the presence of a 500-m headland and a submerged reef. Small changes in wave forcing and tide elevation were found to largely impact circulation patterns. In particular, under 4-m oblique wave conditions, our measurements indicate the presence of an intense low-frequency fluctuating deflection rip flowing against the headland and extending well beyond the surf zone. An XBeach model is further set up to hindcast such flow patterns.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/EiqnjBIkWJE

scholarly journals Assessment of maternal birth satisfaction and intra-partum experiences among the women of rural areas of Tamil Nadu- a cross sectional study

2021 ◽  
Vol 8 (12) ◽  
pp. 6006
Author(s):  
Janakiram Marimuthu ◽  
A. Arul Murugan
Keyword(s):  
Health Care ◽  
Rural Areas ◽  
Tamil Nadu ◽  
Post Partum ◽  
Cross Sectional Study ◽  
Maternal Satisfaction ◽  
Sectional Study ◽  
Cross Sectional ◽  
Birth Satisfaction ◽  
Set Up

Background: Childbirth, though a physiological process, has been associated with multiple risks and stress on the women, even before the time of conception till the post-partum. Every woman around the world has a right to receive respectful maternity care. Birth satisfaction and respectful maternal care has direct impact on percentage of institutional deliveries. There is paucity of studies conducted among the women of rural Tamil Nadu regarding birth satisfaction and intrapartum experiences.Methods: A cross-sectional study was conducted in primary health center area, red hills among the post-partum women attending the immunization OPD at 6, 10 and 14th week after delivery during the months of March to June 2018. By simple random sampling technique 195 subjects were included. A semi-structured questionnaire was administered to collect the data. Ethical clearance was obtained from our Institutional Ethics Committee. Data was entered in MS Excel and analysis was done using SPSS Software version 23.Results: The study shows the importance of maternal satisfaction and intrapartum experiences of women in rural areas. It concluded that the overall satisfaction was 85.5%. The transport facility available at the health care set up which satisfied the mothers was around 91.4%. The interaction of health care providers with mothers during delivery was around 64.5%. Cleanliness and comfort of the delivery area was around 64%. Equality of care provided at the health care set up was around 83%.Conclusions: Reasons for delivery visit, duration of labour, and mode of delivery are independent predictors of maternal satisfaction.

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