measures the electric properties of the formation,
Resistivity is measured as, R in Ohm-meter,
Resistivity is the inverse of conductivity,
The ability to conduct electric current depends upon:
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
DSD-INT 2017 Evaluating Storm Erosion with XBeach on beaches protected by sub...Deltares
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Presentation by Marissa Yates (Saint-Venant Hydraulics Laboratory & Cerema) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Coupling 3D models and earth observation to develop algae foreca...Deltares
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Presentation by Miguel Dionisio Pires, Deltares, The Netherlands, and Yi Hong, Ăcole des Ponts ParisTech, France, at the Delft3D - User Days (Day 3: Water quality and ecology), during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Delft3D FM - validation of hydrodynamics (1D,2D,3D) - van DamDeltares
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Presentation by Arthur van Dam, Deltares, Netherlands, at the Delft3D - User Days (Day 1: Hydrodynamics), during Delft Software Days - Edition 2017. Monday, 30 October 2017, Delft.
Seismic attributes are being used more and more often in the reservoir characterization and interpretation processes. The new software and computerâs development allows today to generate a large number of surface and volume attributes. They proved to be very useful for the facies and reservoir properties distribution in the geological models, helping to improve their quality in the areas between the wells and areas without wells. The seismic attributes can help to better understand the stratigraphic and structural features, the sedimentation processes, lithology variations, etc. By improving the static geological models, the dynamic models are also improved, helping to better understand the reservoirsâ behavior during exploitation. As a result, the estimation of the recoverable hydrocarbon volumes becomes more reliable and the development strategies will become more successful.
measures the electric properties of the formation,
Resistivity is measured as, R in Ohm-meter,
Resistivity is the inverse of conductivity,
The ability to conduct electric current depends upon:
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
DSD-INT 2017 Evaluating Storm Erosion with XBeach on beaches protected by sub...Deltares
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Presentation by Marissa Yates (Saint-Venant Hydraulics Laboratory & Cerema) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Coupling 3D models and earth observation to develop algae foreca...Deltares
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Presentation by Miguel Dionisio Pires, Deltares, The Netherlands, and Yi Hong, Ăcole des Ponts ParisTech, France, at the Delft3D - User Days (Day 3: Water quality and ecology), during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Delft3D FM - validation of hydrodynamics (1D,2D,3D) - van DamDeltares
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Presentation by Arthur van Dam, Deltares, Netherlands, at the Delft3D - User Days (Day 1: Hydrodynamics), during Delft Software Days - Edition 2017. Monday, 30 October 2017, Delft.
Seismic attributes are being used more and more often in the reservoir characterization and interpretation processes. The new software and computerâs development allows today to generate a large number of surface and volume attributes. They proved to be very useful for the facies and reservoir properties distribution in the geological models, helping to improve their quality in the areas between the wells and areas without wells. The seismic attributes can help to better understand the stratigraphic and structural features, the sedimentation processes, lithology variations, etc. By improving the static geological models, the dynamic models are also improved, helping to better understand the reservoirsâ behavior during exploitation. As a result, the estimation of the recoverable hydrocarbon volumes becomes more reliable and the development strategies will become more successful.
DSD-INT 2018 An Engineering Approach to construction of a Storm Surge Model f...Deltares
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Presentation by Edwin Elias, Deltares USA, Inc., USA, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
Itâs hard to get a highly Paid Job without any information & Skills. All the corporate culture needs prior experience. They donât want to waste their resources to the people who donât know. SO come to us, Get yourself trained by knowing the history of the field, business structure, your route of finding a place in one of the biggest job producing markets of the world with just a little effort to develop the skills. TSK- Training For skills and knowledge is the best institute in Rawalpindi Islamabad Pakistan for trainings and courses which leads you towards highly paid jobs. For more info visit www.trainingcourses.com.pk
DSD-INT 2017 Predicting evolution of bathymetry at Duck, NC - VeeramonyDeltares
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Presentation by Jay Veeramony, US Naval Research Laboratory, USA, at the Delft3D - User Days (Day 2: Sediment transport and morphology), during Delft Software Days - Edition 2017. Tuesday, 31 October 2017, Delft.
DSD-INT 2018 Characterizing the drivers of coral reef hydrodynamics at the Ro...Deltares
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Presentation by Camille Grimaldi, University of Western Australia, Australia, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
DSD-INT 2018 A Methodology Study for Model Build and Calibration of 2D Hydrod...Deltares
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Presentation by Edward Shen, Ove ARUP & Partners, Hong Kong, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
DSD-INT 2017 Coastal safety assessment of the Belgian coast with state-of-the...Deltares
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Presentation by Willem Bodde (Witteveen & Bos) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Friday, 3 November 2017, Delft.
The water shortage that has recently struck the Brazilian state of Minas Gerais has led the population and the public authorities to rethink water use in general, re-evaluating its use in the agriculture, industry and services sectors. The mining sector has been the primary focus of this re-evaluation, since it represents approximately 11% of the total water use in the state. One possibility for reducing water consumption by the mining sector would be the use of treated domestic sewage in mining processes.
A case study was conducted in the iron ore mines of the Rio das Velhas Watershed (RVW), which encompasses the principal iron ore producing region in the state of Minas Gerais (268 Mt.year-1). A literature review was performed on the different water quality demands and usages in mining sector (processing, transportation and spraying on roads), taking into account the possibility of use of treated domestic sewage for each process. Additionally, the main sewage treatment processes applied in RVW were also evaluated, and the respective physical and chemical parameters of the treated domestic effluents were studied. The eventual need for complementary treatment for the uses in ore mining, as well as the existing legislation on the use of effluents, were assessed.
DSD-INT 2017 Breaching of coastal defences under extreme storm surges - El S...Deltares
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Presentation by Saber El Sayed (Technische Universität Braunschweig) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Integrated morphological modelling by coupling XBeach with Delft...Deltares
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Presentation by Arjen Luijendijk (Deltares) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Contribution of IG waves to local runup and flooding Beach of Bi...Deltares
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Presentation by Denis Morichon (UniversitĂŠ Pau & Pays de lâAdour) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Friday, 3 November 2017, Delft.
DSD-INT 2017 Vegetated Flow Simulation using Delft3D for a Large-scale Outdoo...Deltares
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Presentation by Un Ji, Korea Institute of Civil Engineering and Building Technology (KICT), Korea, at the Delft3D - User Days (Day 1: Hydrodynamics), during Delft Software Days - Edition 2017. Monday, 30 October 2017, Delft.
DSD-INT 2018 An Engineering Approach to construction of a Storm Surge Model f...Deltares
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Presentation by Edwin Elias, Deltares USA, Inc., USA, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
Itâs hard to get a highly Paid Job without any information & Skills. All the corporate culture needs prior experience. They donât want to waste their resources to the people who donât know. SO come to us, Get yourself trained by knowing the history of the field, business structure, your route of finding a place in one of the biggest job producing markets of the world with just a little effort to develop the skills. TSK- Training For skills and knowledge is the best institute in Rawalpindi Islamabad Pakistan for trainings and courses which leads you towards highly paid jobs. For more info visit www.trainingcourses.com.pk
DSD-INT 2017 Predicting evolution of bathymetry at Duck, NC - VeeramonyDeltares
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Presentation by Jay Veeramony, US Naval Research Laboratory, USA, at the Delft3D - User Days (Day 2: Sediment transport and morphology), during Delft Software Days - Edition 2017. Tuesday, 31 October 2017, Delft.
DSD-INT 2018 Characterizing the drivers of coral reef hydrodynamics at the Ro...Deltares
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Presentation by Camille Grimaldi, University of Western Australia, Australia, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
DSD-INT 2018 A Methodology Study for Model Build and Calibration of 2D Hydrod...Deltares
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Presentation by Edward Shen, Ove ARUP & Partners, Hong Kong, at the Delft3D - User Days (Day 2: Hydrodynamics), during Delft Software Days - Edition 2018. Tuesday, 13 November 2018, Delft.
DSD-INT 2017 Coastal safety assessment of the Belgian coast with state-of-the...Deltares
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Presentation by Willem Bodde (Witteveen & Bos) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Friday, 3 November 2017, Delft.
The water shortage that has recently struck the Brazilian state of Minas Gerais has led the population and the public authorities to rethink water use in general, re-evaluating its use in the agriculture, industry and services sectors. The mining sector has been the primary focus of this re-evaluation, since it represents approximately 11% of the total water use in the state. One possibility for reducing water consumption by the mining sector would be the use of treated domestic sewage in mining processes.
A case study was conducted in the iron ore mines of the Rio das Velhas Watershed (RVW), which encompasses the principal iron ore producing region in the state of Minas Gerais (268 Mt.year-1). A literature review was performed on the different water quality demands and usages in mining sector (processing, transportation and spraying on roads), taking into account the possibility of use of treated domestic sewage for each process. Additionally, the main sewage treatment processes applied in RVW were also evaluated, and the respective physical and chemical parameters of the treated domestic effluents were studied. The eventual need for complementary treatment for the uses in ore mining, as well as the existing legislation on the use of effluents, were assessed.
DSD-INT 2017 Breaching of coastal defences under extreme storm surges - El S...Deltares
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Presentation by Saber El Sayed (Technische Universität Braunschweig) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Integrated morphological modelling by coupling XBeach with Delft...Deltares
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Presentation by Arjen Luijendijk (Deltares) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Wednesday, 1 November 2017, Delft.
DSD-INT 2017 Contribution of IG waves to local runup and flooding Beach of Bi...Deltares
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Presentation by Denis Morichon (UniversitĂŠ Pau & Pays de lâAdour) at the XBeach X (10th Year Anniversary) Conference, during Delft Software Days - Edition 2017. Friday, 3 November 2017, Delft.
DSD-INT 2017 Vegetated Flow Simulation using Delft3D for a Large-scale Outdoo...Deltares
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Presentation by Un Ji, Korea Institute of Civil Engineering and Building Technology (KICT), Korea, at the Delft3D - User Days (Day 1: Hydrodynamics), during Delft Software Days - Edition 2017. Monday, 30 October 2017, Delft.
Review on Hydrodynamic Modelling of Desalination Plants Brine Effluent Marine...IJAEMSJORNAL
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This paper presents a review on hydrodynamic modelling of desalination plants brine effluent marine outfalls. Brine effluent is a byproduct of desalination plants that must be safely discharged with little environmental impacts. Several researchers have been studying the behavior of brine effluent disposal to the sea using marine outfalls but due to its complex behavior yet it is not completely understood, where the international design standards and specifications are limited and there is no unified design approach for the marine outfalls. The dilution and dispersion ability of the ambient water body are discussed. The outfall inclination angle and current speed are also investigated.
The Effect of Geometry Parameters and Flow Characteristics on Erosion and Sed...Dr. Amarjeet Singh
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One of the most critical problems in the river
engineering field is scouring, sedimentation and morphology
of a river bed. In this paper, a finite volume method
FORTRAN code is provided and used. The code is able to
model the sedimentation. The flow and sediment were
modeled at the interception of the two channels. It is applied
an experimental model to evaluate the results. Regarding the
numerical model, the effects of geometry parameters such as
proportion of secondary channel to main channel width and
intersection angle and also hydraulic conditionals like
secondary to main channel discharge ratio and inlet flow
Froude number were studied on bed topographical and flow
pattern. The numerical results show that the maximum
height of bed increased to 32 percent as the discharge ratio
reaches to 51 percent, on average. It is observed that the
maximum height of sedimentation decreases by declining in
main channel to secondary channel Froude number ratio. On
the assessment of the channel width, velocity and final bed
height variations have changed by given trend, in all the
ratios. Also, increasing in the intersection angle accompanied
by decreasing in flow velocity variations along the channel.
The pattern of velocity and topographical bed variations are
also constant in any studied angles.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Experimental conceptualisation of the Flow Net system construction inside the...Dr.Costas Sachpazis
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ABSTRACT
By means of a drainage and seepage tank, an experimental flow net system inside the body of a homogeneous earth embankment dam model, formed from Leighton Buzzard Silica sand, was developed and studied in this experimental research paper.
Water flow through dams is one of the basic problems for geotechnical engineers. Seepage analysis in an important factor to be considered in the proper design of many civil engineering structures. Seepage can occur in both through the structure itself as the case of earth dams and under foundations of an engineering structure. Successful seepage analysis is achieved on the proper and accurate construction of a flow net.
Amongst the various existing methods of seepage analysis, the âFinite Element Methodâ and the method of âExperimental Flow Netsâ are the most widely used ones.
Construction of a flow net is mainly used for solving water flow problems through porous media where the geometry makes sometimes analytical solutions impractical. This method is usually used in soil mechanics, geotechnical or civil engineering as an initial check for problems of water flow under hydraulic structures like embankments or dams. As such, a grid obtained by drawing a series of equipotential lines and stream or flow lines is called a flow net. In this procedure the Laplace equation principles must be satisfied.
Hence, the construction of a flow net is an important tool in analysing two-dimensional irrotational flow problems and provides an approximate solution to the flow problem by following simple rules, as initially set out by Forchheimer, 1900, and later refined by Casagrande,1937. It can also be very useful tool even for problems with complex geometries, as proven in this experimental research paper.
The objectives of this experimental research paper are:
⢠To determine the position and shape of the flow line representing the uppermost free water surface inside the body of a dam by using a drainage and seepage tank,
⢠To conceptualise the flow lines system and to demonstrate that each flow line starts perpendicular to the upstream slope of the dam and that that slope is a boundary equipotential line,
⢠To construct an experimental flow net and subsequently to verify and analyse it by the FEA method,
⢠To calculate the rate of seepage through the dam body, and
⢠To summarise the calculations and experimental findings in a concise and readable format.
In order to achieve these objectives, an experimental flow net system inside the body of a homogeneous earth embankment dam model was formulated by using a drainage and seepage tank.
From the constructed flow net in the present experimental research paper, an attempt has been made to analyze, determine and present the following parameters:
ďź The pressure drop from one side of the embankment to the other,
ďź The seepage flow rate in each flow âchannelâ,
ďź The total seepage flow rate, and
ďź The pore pressure ratio, ru, for the embankment.
APPLICATION OF 1-D HEC-RAS MODEL IN DESIGN OF CHANNELSAM Publications
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Flood occurs at Surat city frequently due to sudden release of water from Ukai dam in river Tapi. At the
time of floods in river Tapi, Surat city and surrounding regions are most affected. The city has faced many floods
since long back. Major flood event occurred in the year 1883, 1884, 1942,1944,1945,1949, 1959, 1968, 1994, 1998,
2002, 2006, 2007 and 2012. The carrying capacity of river is approximately about 4.5 lakhs cusecs (12753 cumecs) at
present. In this, stability of a segment of lower reach approximately 6 km length of Tapi river between Weir cum
causeway and Sardar bridge is evaluated for its carrying capacity and stability in response to discharge and slopes
using HEC-RAS software for past flood data. The study reach consists of 24 cross-sections. The hydraulics model,
HEC-RAS is employed to evaluate flood conveyance performance and also uniform flow computation is carried out.
In the present study existing storm drains are not only marked but based on the HEC-RAS water surface elevation
computation for various flood discharges, need of flood gates on the storm drains are also assessed. The
recommendations are done based on this study either to increase height of bank or construct a retaining wall at
certain sections along the study reach. The present study also recommends installations of flood gates on all the storm
drain outlets which are without flood gates. The width of river in no case be encroached as sections are sensitive high
floods.
âLaboratory experiments on local scour process at wing wall bridge abutments were conducted for different hydraulic conditions and compared with measurements on local scour depths around vertical wall abutments, under the same flow and sediment transport conditions. The study reports an extensive experimental investigation performed in a laboratory flume in the Technological Educational Institute of Thessaly, whose findings are used to describe the effects of different hydraulic parameters on local scour depth variation in the vicinity of the constructions. Three different sizes of wing wall abutment's lengths, transverse to the flow direction, were used in order to investigate the impact of this parameter to local scour variation. The expected bed erosion and the maximum scour depth at the upstream edge of the wing wall abutments are satisfactorily simulated by the experimental procedure. All the experimental results are graphically presented and comparisons between clear-water scour depths around the vertical wall and the wing wall abutments show lower values of scour depths in the vicinity of the wing wall abutments, under the same hydraulic and sediment transport conditions and for the same abutment widths. The experimental data of clear-water scour conditions were used to determine an equation of maximum equilibrium scour depth through regression analysis. The estimated scour depths were in agreement with the experimental values for each abutment geometry.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
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The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83Ă10-07 at 9.04Ă10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
Diabetes is a rapidly and serious health problem in Pakistan. This chronic condition is associated with serious long-term complications, including higher risk of heart disease and stroke. Aggressive treatment of hypertension and hyperlipideamia can result in a substantial reduction in cardiovascular events in patients with diabetes 1. Consequently pharmacist-led diabetes cardiovascular risk (DCVR) clinics have been established in both primary and secondary care sites in NHS Lothian during the past five years. An audit of the pharmaceutical care delivery at the clinics was conducted in order to evaluate practice and to standardize the pharmacistsâ documentation of outcomes. Pharmaceutical care issues (PCI) and patient details were collected both prospectively and retrospectively from three DCVR clinics. The PCI`s were categorized according to a triangularised system consisting of multiple categories. These were âchecksâ, âchangesâ (âchange in drug therapy processâ and âchange in drug therapyâ), âdrug therapy problemsâ and âquality assurance descriptorsâ (âtimer perspectiveâ and âdegree of changeâ). A verified medication assessment tool (MAT) for patients with chronic cardiovascular disease was applied to the patients from one of the clinics. The tool was used to quantify PCI`s and pharmacist actions that were centered on implementing or enforcing clinical guideline standards. A database was developed to be used as an assessment tool and to standardize the documentation of achievement of outcomes. Feedback on the audit of the pharmaceutical care delivery and the database was received from the DCVR clinic pharmacist at a focus group meeting.
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
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Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
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A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
Micro RNA genes and their likely influence in rice (Oryza sativa L.) dynamic ...Open Access Research Paper
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Micro RNAs (miRNAs) are small non-coding RNAs molecules having approximately 18-25 nucleotides, they are present in both plants and animals genomes. MiRNAs have diverse spatial expression patterns and regulate various developmental metabolisms, stress responses and other physiological processes. The dynamic gene expression playing major roles in phenotypic differences in organisms are believed to be controlled by miRNAs. Mutations in regions of regulatory factors, such as miRNA genes or transcription factors (TF) necessitated by dynamic environmental factors or pathogen infections, have tremendous effects on structure and expression of genes. The resultant novel gene products presents potential explanations for constant evolving desirable traits that have long been bred using conventional means, biotechnology or genetic engineering. Rice grain quality, yield, disease tolerance, climate-resilience and palatability properties are not exceptional to miRN Asmutations effects. There are new insights courtesy of high-throughput sequencing and improved proteomic techniques that organismsâ complexity and adaptations are highly contributed by miRNAs containing regulatory networks. This article aims to expound on how rice miRNAs could be driving evolution of traits and highlight the latest miRNA research progress. Moreover, the review accentuates miRNAs grey areas to be addressed and gives recommendations for further studies.
WRIâs brand new âFood Service Playbook for Promoting Sustainable Food Choicesâ gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
A toolkit for identifying and measuring physical streams features from high resolution DEMs and digital image
1. G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
OGRS2014::OtaniemiCampus,AaltoUniversity,Espoo::10-12June2014
A toolkit for identifying andA toolkit for identifying and
measuring physical streams featuresmeasuring physical streams features
from high resolution DEMs andfrom high resolution DEMs and
digital imagedigital image
Authors: C. Cencetti
P. De Rosa
A. Fredduzzi
2. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The problem
â A river is a natural system characterized by continuous
changes (in space and in time).
â In most developed countries, over the past decades, the
morphology of most rivers have suffered huge changes, mainly
due to anthropic interventions.
From Surian & Rinaldi, 2003
The anthropic effects usually
cause a narrowing and incision
of channel leading to a change
of channel type.
Effects:
Change in hydrograph response â flooding
3. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The Challenge
â Stream restoration has emerged as a means to improve aquatic
systems by returning streams to their âpre-disturbed stateâ.
â So hydraulic work or any operation that affect the river should
not (or al least minimize) the disturb to the system.
â Became fundamental understand the âequilibrium stateâ of a
river.
â Fluvial geomorphologists are asked to answer the question: is the
river/channel in equilibrium or disequilibrium?
Fluvial experts use indices as sinuosity index, braiding index,
hydraulic discharge, bankfull limits to support their work
comparing this values over time.
4. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
How to compare this indices over time?
Which elevation is should use to
derive indices as braiding index
(number of channels), flow discharge .
??
Moreover what happens if we
want to compare such indices
over time remembering that the
cross section change in time.
A reference elevation
is required
5. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
In the morphological-sediment study of a water course is useful to define a level (and a
corresponding flow discharge) ârepresentativeâ (and responsible) about the shape and size
of river channel. â Formative discharge.
Bankfull discharge
For a river in equilibrium state the formative discharge is the bankfull discharge or better is the
discharge where streamflow spills onto the floodplain. [Leopold et al., 1964].
The flows effectively able to erode and shape
the channel are not the low discharge (they
flows through a channel) and not the highest
discharge as they are capable of eroding the
channel but they occur so infrequently. It is
reasoned, therefore, that exists a range of
intermediate discharges that do most of the
work of shaping the river channel and that
some summary value of these intermediate
flows represents the formative discharge of the
river (Wolman & Miller, 1960)
The formative discharge corresponds to a discharge with a return period between 1 and 3
years.
Bankfull elevation â bankfull discharge
6. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
formative discharge â bankfull discharge
Bankfull channel â Active channel
Thalweg
â Reconstructing streams to a pre-disturbed state is a difficult task as we know
the landscape never return to its condition before human-disturbance
â We rely on accurate determination of the modern bankfull channel geometry to
approach stream restoration projects.
Bankfull
limits
7. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The hub for all indices
#1: Bankfull discharge
Bankfull elevation
#2: Number of channels
#3: Bankfull width
#4: Hydraulic conveyance
The tool here presented is developed to extract such morphological feature
directly from an high resolution DEM (LiDAR)
#5: Polygon of channel limits
8. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
bankfull elevation
Bankfull location are identified on the following standard field
indicators:
â Break in bank slope corresponding with the active floodplain
â High-flow markers
⢠Limit of bank scour
⢠Roc k staining
⢠Sand/silt deposits
â Vegetation limits
â Bar tops
9. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
bankfull elevation
The bankfull definition becomes difficult to apply in riverbeds recently carved or still
in incision.
It may happen that the "active floodplain" is absent and the bankfull discharge could be
identified as a discharge where flow spills onto a âterraceâ.
This flow may be associated with return periods that excess the 1á3 years - does not
correspond to the formative discharge
The bankfull definition becomes difficult to apply in riverbeds recently carved or still
in incision.
It may happen that the "active floodplain" is absent and the bankfull discharge could be
identified as a discharge where flow spills onto a âterraceâ.
This flow may be associated with return periods that excess the 1á3 years - does not
correspond to the formative discharge
11. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The methodology
The idea behind the tool is based
exclusively on the bank/floodplain
slope break.
For each cross section, is graphed the
hydraulic depth as a function of flow
elevation.
The (local) maximum value of this
function indicates a the elevation where
water spills across the floodplain
(approach suggested by McKean
&Wright 2005 as variant of Williams
1978)
12. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The tool
The tool developed is able to:
â graph the hydraulic depth vs the elevation
â investigate such function to locate the local maxima and select the
first local max corresponding to the first break in slope.
13. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The tool
The tool developed is able to:
â graph the hydraulic depth vs the elevation
â investigate such function to locate the local maxima and select the
first local max corresponding to the first break in slope.
14. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The methodology â limitation
ISSUE:
1)We experienced that the
methodology work better in rivers
with floodplain and would be limited
in confined channels that miss
floodplains.
2)The method is less definitive in
channel with multiple terrace,
where could be tricky decide which
terrace and which plateaux in the
hydraulic depth function correspond
to the current bankfull elevation
A specific smoothing procedure
is required to find the
âsignificantâ local maxima
(remove noise)
15. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The QGIS plugin
The tool have been implemented as QGIS plugin ant it have two main steps:
1) Cross sections generation from river axis known longitudinal step and
width
2) Evaluation of bankfull elevation (following the proposed methodology) for
each cross section and deriving of all morphological features.
In tab âNumerical settingâ the user select the vertical steps and the minimum hydraulic depth.
1
2
16. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The numerical parameters
Vertical steps: it defines the number of
points in function.
+ High values are more sensitive for
small slope variations
- High computational time
Usually > 500
Minimum hydraulic depth: this setting is to filter
out local maxima below such value.
Usually: 0.5 m
17. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The spline smoothing procedure I
A smoothing procedure, based on splines function, is
required to remove local maxima not significant (ânoiseâ).
â Explore the range 0á1
for 100 smoothing
parameter (spar).
â To select the best âsparâ
parameter a k-fold cross
validation is used.
â For each âsparâ
parameter the mean
square error and the 1sd
is computed
Black dots represent
the mean square error
and the grey bar the
1sd
The spar selection
18. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
The spline smoothing procedure II
A smoothing procedure, based on splines function, is
required to remove local maxima not significant (ânoiseâ).
â spar parameter with
minimum error
â The corresponding 1sd
â The highest spar
parameter, just smaller
that 1sd, is selected
The spar parameter:
1)non significantly
different from the
minimum
2)Big enough to
smooth data and
remove noise
19. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Evaluation of bankfull elevation
we found the local
maxima looking for
the zero function of
1st and 2nd
derivative of spline
using the
newthon-rampson
method.
The figure shows howThe figure shows how
this approach is ablethis approach is able
to remove small localto remove small local
maxima for a bettermaxima for a better
identification ofidentification of
bankfull elevationbankfull elevation
No selectedNo selected
local maximalocal maxima
20. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Polygon limits for multiple channels
In case of multiple channel the
tool locate the polygon limits to
the channel with wet area max.
Channel limits
Banfull width
23. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
a
Case study: Paglia River â central Italy
Wandering river in a strong
disequilibrium state.
â Narrowing and incision
processes
â Change in channel
morphology from a
braided river to a
wandering
â The old active floodplain
works now as a
morphological terrace
â The active floodplain is
now inside the old
riverbed, before the
narrowing process started.
The blue line is the polygon output of the tool: refers to the
limits of the main channel related to the bankfull elevation.
25. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Local incongruence?
Local
incongruence (a)
between main
channel limits and
aerial photo does
not appear in the
shaded map.
There is a shift in
time between
LiDAR survey and
orthofoto date.
26. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Result: number of channels vs bankfull width
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
0
50
100
150
200
250
0
1
2
3
4
5
6
7
bankfull width channels
width(m)
#ofchannels
In a equilibrium
river # of channel
is proportional to
the bankfull width.
The proportion
looks altered.
The floodplain is
going to became a
terrace.
27. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
0
100
200
300
400
500
600
700
800
900
1000
0
50
100
150
200
250
300
wet area
Bankfull di-
scharge
m3/s
Area(m2)
Result: wet area and bankfull discharge
A good correlation between discharge and wet area.
1)For some cross section the proportion is altered (see 13á14 and 26á27) â low bed slope
2)Section 1 has very higher value of area â high discharge
Q =Ďâ Sâ âR j
29. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Result: discharge variation and water table
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
-2
0
2
4
6
8
10
12
14
16
130
135
140
145
150
155
maxWT
WT linear
egression
variation
As the discharge may be affected by global error, as the DTM LiDAR does not include
the under-water, we should be more interested in variation rather that the discharge
itself.
Potential pitfall
XS # 26 â Increasing of cross section area.
XS #1 â carved cross section.
30. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
Conclusions
â Advantages
â The tool/plugin is designed to be extremely simple to use (a DEM
input and two numerical parameters).
â The tool use a robust methodological approach.
â The bankfull limits are correctly located compared to aerial photo.
â Several parameters useful to evaluate the âstateâ of a river.
â Few tool that extract river morphological features exists already
implemented in a GIS environment
â Disadvantages
â The methodology base the location of bankfull limits only on the
slope/break in slope. Some other collateral indicators, from aerial
photo (?), using image classification procedure could/should be
inserted.
â The tool is less definitive for river that miss floodplain, or in strong
disequilibrium, or for braided rivers.
31. OGRS2014âOtaniemiCampus,AaltoUniversity,Espoo
G EOMORPHOLOGICAL FEATURES EXTRACTION FROM HIGH RESOLUTION DEM S
C.Cencetti, P.De Rosa, A.Fredduzzi.
THANKS FOR YOUR ATTENTIONTHANKS FOR YOUR ATTENTION
The authors acknowledge Luca Scrucca for the collaboration in theThe authors acknowledge Luca Scrucca for the collaboration in the
the statistical smoothing procedure.the statistical smoothing procedure.
Plugin available at:
https://github.com/pierluigiderosa/BankFullDetection