Estimate of Storm Induced Beach Erosion Through the ETS Approach

2008 ◽  
Author(s):  
Rosaria E. Musumeci ◽  
Carla Faraci ◽  
Felice Arena ◽  
Enrico Foti
Keyword(s):  
Return Period ◽  
Extreme Events ◽  
Coastal Erosion ◽  
Beach Erosion ◽  
Coastal Protection ◽  
Shoreline Retreat ◽  
Submerged Breakwater ◽  
The One

In the present paper the risk of beach erosion is evaluated by applying the Equivalent Triangular Storm (ETS). The selected case study is ‘La Plaja’ beach located in the South of Catania, Sicily. The proposed approach has shown that when the ETS model is applied, a shoreline retreat has been found which on average overestimates the one obtained by means of actual storm data of about 35%. The model has been applied for the determination of the return period of shoreline recession due to beach erosion during extreme events in order to recover risk maps, which can provide useful information in the planning of coastal interventions. Finally the model has been applied to predict the shoreline retreat in the presence of a submerged breakwater, confirming that the introduction of such coastal protection work strongly limits the risk of coastal erosion.

scholarly journals Analysis of Problems Related to the Calculation of Flood Frequency Using Rainfall-Runoff Models: A Case Study in Poland

2020 ◽  
Vol 12 (17) ◽  
pp. 7187
Author(s):  
Dariusz Młyński
Keyword(s):  
Sensitivity Analysis ◽  
Return Period ◽  
Maximum Flow ◽  
High Sensitivity ◽  
Flood Frequency ◽  
Rainfall Runoff ◽  
Model Quality ◽  
Retention Capacity

This work aimed to quantify how the different parameters of the Snyder model influence the errors in design flows. The study was conducted for the Kamienica Nowojowska catchment (Poland). The analysis was carried out according to the following stages: determination of design precipitation, determination of design hyetograph, sensitivity analysis of the Snyder model, and quality assessment of the Snyder model. Based on the conducted research, it was found that the Snyder model did not show high sensitivity to the assumed precipitation distribution. The parameters depending on the retention capacity of the catchment had much greater impact on the obtained flow values. The verification of the model quality showed a significant disproportion in the calculated maximum flow values with the assumed return period.

Determination Of The Optimal Guide Curve For A Reservoir, Case Study Copa Dam, Boyacá

2020 ◽  
Author(s):  
Felipe Sierra ◽  
Jorge Sanabria ◽  
Gerald Corzo ◽  
Germán Santos
Keyword(s):  
Hydrological Model ◽  
Irrigation District ◽  
Maximum Rainfall ◽  
Annual Series ◽  
Continuous Simulation ◽  
Hydrological System ◽  
Flow Through ◽  
The One

<p>Reservoir operation has been a task that always relate to integrated water resources concepts, the rules of such systems require to adapt to changes in the uses of water or in their prioritization. The storage body of La Copa reservoir, located in the upper Chicamocha river basin in Colombia was originally built with the objective of mitigating the floods over the upper Chicamocha valley. However, an irrigation district was latter established, with the objective of supplying water to farmers. This study presents the analysis and optimization of operational rules to minimize the likelihood of floods and shortages for the irrigation district. This is done by contemplating the uncertainty in the hydrological system.</p><p>A methodology is developed to obtain the optimal management and operation of the reservoir, aiming at reducing droughts and flood, which will end up in a regulated basins. A simulation model of the reservoir using the HEC-ResSim tool was used to aim at an optimal guide curve. The guide curve in this study is the base for operational decisions. A continuous simulation hydrological model using the HEC-HMS tool. The model was calibrated using annual series of daily flows as input into the reservoir model.  A two-dimensional hydrodynamic model using (HEC-RAS 2D) was used to test the results of regulation through the comparison of the simulations of the current and optimal regulation conditions.  Several guide curves were developed for the evaluation of the operation. Four of them among are selected and tested using the HEC-ResSim model through the quantification of the minimum and maximum volumes discharge failures. Finally, the guide curve with the least number of failures was selected as the one that provides the best system operation. The benefits of the selected guide curve were verified by the transit of the regulated hydrographs in the 2D hydraulic model. The simulation was carried out in the most period in terms of flows and maximum rainfall, from April 06 to May 15, 2011. The period between April 15 and 21 has the highest flow through the critical sector. On the other hand, unregulated conditions were evaluated using the flows of the hydrological model. It is found that the channel presents a notable improvement, in the simulation of April 15, through the discharges made in a controlled manner from the La Copa reservoir. The methodology presents a simple and practical way to obtain relative optimal operational rules for a multipurpose storage.</p>

scholarly journals Selection of Appropriate Coastal Protection Structure Using AHP Method

2020 ◽  
Vol 2 (1) ◽  
pp. 4
Author(s):  
Barbara Karleuša ◽  
Nino Krvavica ◽  
Igor Ružić
Keyword(s):  
Coastal Protection ◽  
Analysis Method ◽  
Ahp Method ◽  
Analytic Hierarchy ◽  
Submerged Breakwater ◽  
Criteria Importance ◽  
Hierarchy Process ◽  
North Western ◽  
Selection Of

The selection of an appropriate coastal protection structure using multi-criteria analysis method AHP (analytic hierarchy process) was presented by a case study of a beach reconstruction in the Kostanj Bay (north-western part of Croatia). The newly designed beach (about 300 m long) will be formed on the western part of the bay by the additional filling of the natural rocky coastline with gravel and building reinforced concrete seawalls towards the sea. The beach will be protected by a submerged breakwater. Five different alternatives were analysed and defined by a different design of the protective breakwater. The first alternative, without the submerged breakwater, was considered as the baseline alternative. An additional four alternatives were examined based on four criteria and five sub-criteria, which considered the technical, economic, social and environmental impacts. The sensitivity of the ranking for the considered alternatives was analysed using five criteria importance scenarios.

scholarly journals LAND USE AND MITIGATION EFFECTS ON BARRIER BEACH EROSION IN STORMS: CASE STUDY IN RHODE ISLAND

2018 ◽  
pp. 108
Author(s):  
Naser Al Naser ◽  
Annette Grilli ◽  
Stephan Grilli ◽  
Christopher Baxter ◽  
Aaron Bradshaw ◽  
...  
Keyword(s):  
Rhode Island ◽  
Coastal Erosion ◽  
Barrier Islands ◽  
Beach Erosion ◽  
Coastal Protection ◽  
State Agencies ◽  
Barrier Beach ◽  
The North ◽  
To Come ◽  
A Chain

Sea Level Rise (SLR) and storm intensification lead to re-evaluating inundation assessments along the North Atlantic US shoreline. A particular effort is devoted to assessing coastal community risk to “100-year storm” events in Rhode Island, US, using a chain of state-of-the-art storm surge, wave propagation, and coastal erosion 2D models. Damage risks imposed on infrastructures and services incited US federal and state agencies to come up with innovative engineering solutions to improve coastal resiliency while preserving natural coastal and marine environments. This study critically evaluates available design tools used to assess the performance of two types of Natural and Natural Based Features (NNBFs) for coastal protection: natural vegetated barrier islands and dunes reinforced with Geotextile Sand-filled Containers (GSCs), on urbanized barrier islands. Comparative analyses with field data identifies the capabilities and limitations of phase averaging and phase resolving hydro-morphodynamic models used for simulating bed level changes in dissipative beaches, during 3 Sallenger storm regimes. Recommendations are provided on modeling approaches for simulating effects of vegetation and using GSCs to limit coastal erosion.

scholarly journals Coastal Structures as Beach Erosion Control and Sea Level Rise Adaptation in Malaysia: A Review

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1741
Author(s):  
Ahmad Hadi Mohamed Rashidi ◽  
Mohamad Hidayat Jamal ◽  
Mohamad Zaki Hassan ◽  
Siti Salihah Mohd Sendek ◽  
Syazana Lyana Mohd Sopie ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Coastal Erosion ◽  
Management Strategies ◽  
Erosion Control ◽  
Beach Erosion ◽  
Coastal Protection ◽  
Sea Level Rise Adaptation ◽  
Erosion Protection ◽  
And Sea Level

The shoreline of Malaysia is exposed to threats of coastal erosion and a rise of sea level. The National Coastal Erosion Study, 2015 reported that 15% of an 8840 km shoreline is currently eroding, where one-third of those falls under the critical and significant categories that require structural protection. The Study of Sea Level Rise in Malaysia, 2017 presented a sea-level increase of 0.67–0.74 mm on average yearly. This study reviewed selected coastal protection structures along the shoreline of Malaysia as an erosion control and sea-level rise adaptation based on coastal management strategies. Hard structures such as rock revetment and breakwater are commonly used as erosion protection systems in the “hold the line” strategy. Increased platform level of seawalls and earth bunds, considered as an “adaptation” approach, are effective in erosion protection and are adaptive to sea-level rise. Mangrove replanting is suitable as a “limited intervention” approach in minimizing the long-term impact of both threats. However, offshore breakwater, groyne, and geotextile tubes are solely for protection purposes and are not as effective for sea-level rise adaptation. As the sea level is continuously increasing, their function as coastal protection will also become less effective. In summary, this comprehensive review on coastal protection in Malaysia will benefit the related agencies on the future assessment.

scholarly journals Determination of Submerged Breakwater Location for Coastal Protection in Panjang Island Waters Jepara

2019 ◽  
Vol 4 (5) ◽  
pp. 346-351 ◽  
Author(s):  
Denny Nugroho Sugianto ◽  
Purwanto Purwanto ◽  
Gentur Handoyo ◽  
Aulia Oktaviani ◽  
Kunarso Kunarso ◽  
...  
Keyword(s):  
Coastal Protection ◽  
Submerged Breakwater

scholarly journals LONG TERM BEACH EROSION: MORPHODYNAMIC CASE STUDY IN MONT-ROIG BEACH, SPAIN

2012 ◽  
Vol 1 (33) ◽  
pp. 68
Author(s):  
Jordi Galofré ◽  
Jordi Galofré ◽  
Dolores Ortiz ◽  
Raúl Medina
Keyword(s):  
Coastal Erosion ◽  
Numerical Models ◽  
Anthropogenic Impacts ◽  
Wave Climate ◽  
Sediment Supply ◽  
Beach Erosion ◽  
Classical Analysis ◽  
Morphological Aspects

Long term coastal erosion in beaches induced by long-shore sediment transport is an important aspect to be taken account in beach behavior. If anthropogenic impacts in coastal stretch (harbor, detached breakwaters, lack of sediments from streams and gullies, and urban pressure) interrupting long-shore currents and transport and decreasing sediment supply, the coastal equilibrium disappears. In this paper a case study is shown in order to analyze long term beach behavior in a coastal stretch affected by erosion. After a brief description of morphological aspects, causes and effects that have incidence on the case study area will be shown. General background and coastal works are detailed. The ideas based on a classical analysis of beach behavior are exposed and results obtained from bathymetric analysis and numerical models are showed. Morphology, wave climate, morphodynamics and sediment budget are evaluated and morphodynamic beach behavior is proposed. A diagnosis is made and mitigation proposal for coastal erosion will be proposed.

scholarly journals Multivariate return periods of sea storms for coastal erosion risk assessment

2012 ◽  
Vol 12 (8) ◽  
pp. 2699-2708 ◽  
Author(s):  
S. Corbella ◽  
D. D. Stretch
Keyword(s):  
Return Period ◽  
Coastal Erosion ◽  
Design Method ◽  
Return Periods ◽  
Current Form ◽  
Erosion Risk ◽  
Storm Characteristics ◽  
Relationship Of ◽  
The Relationship

Abstract. The erosion of a beach depends on various storm characteristics. Ideally, the risk associated with a storm would be described by a single multivariate return period that is also representative of the erosion risk, i.e. a 100 yr multivariate storm return period would cause a 100 yr erosion return period. Unfortunately, a specific probability level may be associated with numerous combinations of storm characteristics. These combinations, despite having the same multivariate probability, may cause very different erosion outcomes. This paper explores this ambiguity problem in the context of copula based multivariate return periods and using a case study at Durban on the east coast of South Africa. Simulations were used to correlate multivariate return periods of historical events to return periods of estimated storm induced erosion volumes. In addition, the relationship of the most-likely design event (Salvadori et al., 2011) to coastal erosion was investigated. It was found that the multivariate return periods for wave height and duration had the highest correlation to erosion return periods. The most-likely design event was found to be an inadequate design method in its current form. We explore the inclusion of conditions based on the physical realizability of wave events and the use of multivariate linear regression to relate storm parameters to erosion computed from a process based model. Establishing a link between storm statistics and erosion consequences can resolve the ambiguity between multivariate storm return periods and associated erosion return periods.

Two-Stage Procedure for the Quantitative Determination of Autoprothrombin III Concentration and Some Applications

1967 ◽  
Vol 18 (01/02) ◽  
pp. 198-210 ◽  
Author(s):  
Ronald S Reno ◽  
Walter H Seegers
Keyword(s):  
Prothrombin Time ◽  
Factor Vii ◽  
Two Stage ◽  
Pronounced Increase ◽  
One Stage ◽  
Assay Procedure ◽  
Bovine Plasma ◽  
The One ◽  
Autoprothrombin C

SummaryA two-stage assay procedure was developed for the determination of the autoprothrombin C titre which can be developed from prothrombin or autoprothrombin III containing solutions. The proenzyme is activated by Russell’s viper venom and the autoprothrombin C activity that appears is measured by its ability to shorten the partial thromboplastin time of bovine plasma.Using the assay, the autoprothrombin C titre was determined in the plasma of several species, as well as the percentage of it remaining in the serum from blood clotted in glass test tubes. Much autoprothrombin III remains in human serum. With sufficient thromboplastin it was completely utilized. Plasma from selected patients with coagulation disorders was assayed and only Stuart plasma was abnormal. In so-called factor VII, IX, and P.T.A. deficiency the autoprothrombin C titre and thrombin titre that could be developed was normal. In one case (prethrombin irregularity) practically no thrombin titre developed but the amount of autoprothrombin C which generated was in the normal range.Dogs were treated with Dicumarol and the autoprothrombin C titre that could be developed from their plasmas decreased until only traces could be detected. This coincided with a lowering of the thrombin titre that could be developed and a prolongation of the one-stage prothrombin time. While the Dicumarol was acting, the dogs were given an infusion of purified bovine prothrombin and the levels of autoprothrombin C, thrombin and one-stage prothrombin time were followed for several hours. The tests became normal immediately after the infusion and then went back to preinfusion levels over a period of 24 hrs.In other dogs the effect of Dicumarol was reversed by giving vitamin K1 intravenously. The effect of the vitamin was noticed as early as 20 min after administration.In response to vitamin K the most pronounced increase was with that portion of the prothrombin molecule which yields thrombin. The proportion of that protein with respect to the precursor of autoprothrombin C increased during the first hour and then started to go down and after 3 hrs was equal to the proportion normally found in plasma.

A novel method for the determination of linting propensity of paper

TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD
Keyword(s):  
Ash Content ◽  
The Novel ◽  
Offset Printing ◽  
Excellent Correlation ◽  
End Conditions ◽  
Bottom Side ◽  
Novel Method ◽  
Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

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