scholarly journals Uncertainty Assessment: Reservoir Inflow Forecasting with Ensemble Precipitation Forecasts and HEC-HMS

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Sheng-Chi Yang ◽  
Tsun-Hua Yang
Keyword(s):  
Lead Time ◽  
Hydrological Model ◽  
Extreme Event ◽  
Uncertainty Assessment ◽  
Individual Member ◽  
Weather Model ◽  
Inflow Forecasting ◽  
Shihmen Reservoir ◽  
Reservoir Inflow ◽  
The Impact

During an extreme event, having accurate inflow forecasting with enough lead time helps reservoir operators decrease the impact of floods downstream. Furthermore, being able to efficiently operate reservoirs could help maximize flood protection while saving water for drier times of the year. This study combines ensemble quantitative precipitation forecasts and a hydrological model to provide a 3-day reservoir inflow in the Shihmen Reservoir, Taiwan. A total of six historical typhoons were used for model calibration, validation, and application. An understanding of cascaded uncertainties from the numerical weather model through the hydrological model is necessary for a better use for forecasting. This study thus conducted an assessment of forecast uncertainty on magnitude and timing of peak and cumulative inflows. It found that using the ensemble-mean had less uncertainty than randomly selecting individual member. The inflow forecasts with shorter length of cumulative time had a higher uncertainty. The results showed that using the ensemble precipitation forecasts with the hydrological model would have the advantage of extra lead time and serve as a valuable reference for operating reservoirs.

scholarly journals A physically-based parsimonious hydrological model for flash floods in Mediterranean catchments

2011 ◽  
Vol 11 (9) ◽  
pp. 2567-2582 ◽  
Author(s):  
H. Roux ◽  
D. Labat ◽  
P.-A. Garambois ◽  
M.-M. Maubourguet ◽  
J. Chorda ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Soil Properties ◽  
Overland Flow ◽  
Hydrological Model ◽  
Extreme Event ◽  
Model Parameters ◽  
Peak Time ◽  
Efficiency Coefficient ◽  
Soil Saturation ◽  
The Impact

Abstract. A spatially distributed hydrological model, dedicated to flood simulation, is developed on the basis of physical process representation (infiltration, overland flow, channel routing). Estimation of model parameters requires data concerning topography, soil properties, vegetation and land use. Four parameters are calibrated for the entire catchment using one flood event. Model sensitivity to individual parameters is assessed using Monte-Carlo simulations. Results of this sensitivity analysis with a criterion based on the Nash efficiency coefficient and the error of peak time and runoff are used to calibrate the model. This procedure is tested on the Gardon d'Anduze catchment, located in the Mediterranean zone of southern France. A first validation is conducted using three flood events with different hydrometeorological characteristics. This sensitivity analysis along with validation tests illustrates the predictive capability of the model and points out the possible improvements on the model's structure and parameterization for flash flood forecasting, especially in ungauged basins. Concerning the model structure, results show that water transfer through the subsurface zone also contributes to the hydrograph response to an extreme event, especially during the recession period. Maps of soil saturation emphasize the impact of rainfall and soil properties variability on these dynamics. Adding a subsurface flow component in the simulation also greatly impacts the spatial distribution of soil saturation and shows the importance of the drainage network. Measures of such distributed variables would help discriminating between different possible model structures.

scholarly journals Propagation of hydro-meteorological uncertainty in a model cascade framework to inundation prediction

2015 ◽  
Vol 19 (7) ◽  
pp. 2981-2998 ◽  
Author(s):  
J. P. Rodríguez-Rincón ◽  
A. Pedrozo-Acuña ◽  
J. A. Breña-Naranjo
Keyword(s):  
Hydrodynamic Model ◽  
Hydrological Model ◽  
Extreme Event ◽  
Weather Prediction ◽  
Uncertainty Assessment ◽  
Distributed Hydrological Model ◽  
Flood Prediction ◽  
Meteorological Model ◽  
Ensemble Technique ◽  
Rainfall Prediction

Abstract. This investigation aims to study the propagation of meteorological uncertainty within a cascade modelling approach to flood prediction. The methodology was comprised of a numerical weather prediction (NWP) model, a distributed rainfall–runoff model and a 2-D hydrodynamic model. The uncertainty evaluation was carried out at the meteorological and hydrological levels of the model chain, which enabled the investigation of how errors that originated in the rainfall prediction interact at a catchment level and propagate to an estimated inundation area and depth. For this, a hindcast scenario is utilised removing non-behavioural ensemble members at each stage, based on the fit with observed data. At the hydrodynamic level, an uncertainty assessment was not incorporated; instead, the model was setup following guidelines for the best possible representation of the case study. The selected extreme event corresponds to a flood that took place in the southeast of Mexico during November 2009, for which field data (e.g. rain gauges; discharge) and satellite imagery were available. Uncertainty in the meteorological model was estimated by means of a multi-physics ensemble technique, which is designed to represent errors from our limited knowledge of the processes generating precipitation. In the hydrological model, a multi-response validation was implemented through the definition of six sets of plausible parameters from past flood events. Precipitation fields from the meteorological model were employed as input in a distributed hydrological model, and resulting flood hydrographs were used as forcing conditions in the 2-D hydrodynamic model. The evolution of skill within the model cascade shows a complex aggregation of errors between models, suggesting that in valley-filling events hydro-meteorological uncertainty has a larger effect on inundation depths than that observed in estimated flood inundation extents.

AFRICA’S RENAISSANCE AND POTENTIAL IN THE LEATHER SECTOR WITH REFLECTION TO THE GLOBAL PERFORMANCE

2015 ◽  
Vol 2 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Mwinyihija M.
Keyword(s):  
Value Chain ◽  
Small And Medium Enterprises ◽  
Middle Level ◽  
Individual Member ◽  
Socioeconomic Indicators ◽  
Value Add ◽  
Medium Enterprises ◽  
The Impact ◽  
Productivity And Competitiveness ◽  
Critical Aspects

Africa’s renaissance is inevitable and rapidly emerging as a reality in tandem with the continent’s continued exploration of its natural resources in a more sustained way than previously done. Currently, the clarion call is to value add, avoid plundering and involve its population through the SME’s to adapt modern methods of entrepreneurship. During the study, critical aspects that are envisaged to trigger the growth and development of Africa, included the entry of major countries of the continent into the global emerging markets such as MINT (Mexico, Indonesia, Nigeria and Turkey) and BRICS (Brazil, Russia, India, China and South Africa). For the leather sector, certain socioeconomic indicators such as the youthful participation in the value chain, ownership status, literacy levels and acquired experiences are all contributing to a vibrant sector. It was observed that these indicators if well aligned with individual member states of African Union Commission and structured than productivity and competitiveness of leather products will be attained. As such, ease of either foreign direct investment, local recapitalization and development of the SME’s could become feasible. Indeed, with the emergence of over 300 million youth at middle level income level is construed to start building on the impact of the continents purchasing power. Therefore, Africa needs to respond by address on development of ICT, develop affordable financial support to provide stimulus packages to SME’s (Small and Medium Enterprises) to transform, improve on inter and intra trade to optimize on unexplored synergies and enhance mobility of persons with in Africa as preamble to Africa’s renaissance.

The ROLE OF CHINA-PAK ECONOMIC CORRIDOR (CPEC) IN LOGISTIC SYSTEM OF PAKISTAN’S AND CHINA’S

2019 ◽  
Vol 6 (1) ◽  
pp. 48-50
Author(s):  
Ikram Uddin
Keyword(s):  
Persian Gulf ◽  
Lead Time ◽  
Fiber Optic ◽  
Delivery Time ◽  
Fiber Optic Cable ◽  
Total Cost ◽  
Economic Complexity ◽  
Shipping Cost ◽  
The Impact

This study will explain the impact of China-Pak Economic Corridor (CPEC) on logistic system of China and Pakistan. This project is estimated investment of US $90 billion, CPEC project is consists of various sub-projects including energy, road, railway and fiber optic cable but major portion will be spent on energy. This project will start from Kashgar port of china to Gwadar port of Pakistan. Transportation is sub-function of logistic that consists of 44% total cost of logistic system and 20% total cost of production of manufacturing and mainly shipping cost and transit/delivery time are critical for logistic system. According to OEC (The Observing Economic Complexity) currently, china is importing crude oil which 13.4% from Persian Gulf. CPEC will china for lead time that will be reduced from 45 days to 10 days and distance from 2500km to 1300km. This new route will help to china for less transit/deliver time and shipping cost in terms of logistic of china. Pakistan’s transportation will also improve through road, railway and fiber optic cabal projects from Karachi-Peshawar it will have speed 160km per hour and with help of pipeline between Gwadar to Nawabshah gas will be transported from Iran. According to (www.cpec.inf.com) Pakistan logistic industry will grow by US $30.77 billion in the end of 2020.

A Streamflow and Water Level Forecasting Model for the Ganges, Brahmaputra, and Meghna Rivers with Requisite Simplicity

2018 ◽  
Vol 19 (1) ◽  
pp. 201-225 ◽  
Author(s):  
Wahid Palash ◽  
Yudan Jiang ◽  
Ali S. Akanda ◽  
David L. Small ◽  
Amin Nozari ◽  
...  
Keyword(s):  
Water Level ◽  
Lead Time ◽  
Large Scale ◽  
Predictive Ability ◽  
Large River ◽  
Modeling Framework ◽  
Forecasting Accuracy ◽  
Weather Model ◽  
And Performance ◽  
The Ganges

A forecasting lead time of 5–10 days is desired to increase the flood response and preparedness for large river basins. Large uncertainty in observed and forecasted rainfall appears to be a key bottleneck in providing reliable flood forecasting. Significant efforts continue to be devoted to developing mechanistic hydrological models and statistical and satellite-driven methods to increase the forecasting lead time without exploring the functional utility of these complicated methods. This paper examines the utility of a data-based modeling framework with requisite simplicity that identifies key variables and processes and develops ways to track their evolution and performance. Findings suggest that models with requisite simplicity—relying on flow persistence, aggregated upstream rainfall, and travel time—can provide reliable flood forecasts comparable to relatively more complicated methods for up to 10 days lead time for the Ganges, Brahmaputra, and upper Meghna (GBM) gauging locations inside Bangladesh. Forecasting accuracy improves further by including weather-model-generated forecasted rainfall into the forecasting scheme. The use of water level in the model provides equally good forecasting accuracy for these rivers. The findings of the study also suggest that large-scale rainfall patterns captured by the satellites or weather models and their “predictive ability” of future rainfall are useful in a data-driven model to obtain skillful flood forecasts up to 10 days for the GBM basins. Ease of operationalization and reliable forecasting accuracy of the proposed framework is of particular importance for large rivers, where access to upstream gauge-measured rainfall and flow data are limited, and detailed modeling approaches are operationally prohibitive and functionally ineffective.

Numerical Study of Corrugated Metal Panels Subjected to Windborne Debris Impacts

2014 ◽  
Vol 626 ◽  
pp. 109-114
Author(s):  
Wen Su Chen ◽  
Hong Hao ◽  
Hao Du
Keyword(s):  
Extreme Event ◽  
Numerical Study ◽  
Numerical Models ◽  
Economic Loss ◽  
Wind Loading ◽  
Windborne Debris ◽  
Study Laboratory ◽  
The Impact ◽  
Metal Panels ◽  
Corrugated Metal

Hurricane, typhoon and cyclone take place more and more often around the world with changing climate. Such nature disasters cause tremendous economic loss and casualty. Various kinds of windborne debris such as compact-like, plate-like and rod-like objects driven by hurricane usually imposes localized impact loading on the structure envelopes such as cladding, wall or roof, etc. The dominant opening in the envelope might cause serious damage to the structures, even collapse. To withstand the impact of such extreme event, the requirements on panel capacity to resist windborne debris impact has been presented in the Australian Wind Loading Code (2011) [1]. Corrugated metal panels are widely used as building envelop. In a previous study, laboratory tests have been carried out to investigate the performance of corrugated metal panels subjected to a 4kg wooden projectile by considering various impact locations, impact velocities and boundary conditions. In this study, numerical models were developed to simulate the responses of the corrugated metal panels subjected to wooden debris impacts by using commercial software LS-DYNA. The predicted data from the numerical simulations were compared with the experimental results. The validated numerical model can be used to conduct intensive numerical simulation to study the failure probabilities of corrugated structural panels subjected to windborne debris impacts.

scholarly journals AB1174 TRACKING THE EFFECTS ON A CLINICAL SERVICE OF INTRODUCING ULTRASOUND FOR DIAGNOSIS OF GIANT CELL ARTERITIS: DESIGN OF A SERVICE EVALUATION USING LEAN METHODOLOGY

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1877.2-1878
Author(s):  
S. Mackie ◽  
A. Barr ◽  
A. Cracknell ◽  
S. Farrell ◽  
J. Parvin ◽  
...  
Keyword(s):  
Lead Time ◽  
Axillary Artery ◽  
Care Pathway ◽  
Temporal Artery ◽  
Service Evaluation ◽  
Significant Shift ◽  
Temporal Artery Biopsy ◽  
Prednisolone Dose ◽  
Patient Feedback ◽  
The Impact

Background:In our large, multi-site hospital, patients with suspected GCA are started promptly on high-dose prednisolone but until 2019, patients waited for temporal artery biopsy (TAB) until the GCA diagnosis could be confirmed (“GCA”) or refuted (“not-GCA”). Reports of the impact of introducing temporal and axillary artery ultrasound (TAUS) have mainly come from smaller hospitals. Agreement between TAUS and TAB has been reported by others with a Cohen’s kappa of 0.35 [1] and 0.40 [2]. We used Lean methodology to identify metrics across 5 key domains: delivery, quality, service, morale and cost.Objectives:To design metrics for a service evaluation to measure impact of introducing TAUS, and to test their feasibility of measurement within routine care.Methods:Our primary driver was time from presenting to our service to diagnostic confirmation (lead time). Pathway mapping, value stream mapping and a driver diagram identified key ideas for improvement.We chose to measure: Delivery (mean lead time for each month), Quality (proportion of patients with GCA and positive TAB/TAUS; total (cumulative) prednisolone dose in patients with not-GCA, Service (patient feedback), Morale (staff feedback) and Cost (number of patients; cost of tests per patient; overall costs). We plotted these by month on run charts and defined a significant shift as 6 consecutive monthly values below baseline median. Cohen’s kappa was calculated using GraphPad QuickCalcs.Results:Routine TAUS for suspected GCA was introduced from January 2019, alongside a multidisciplinary team monthly meeting. TAUS was done a median of 2.5 days from referral. Agreement between TAB and TAUS results was good (Table 1). The run chart showed a significant shift in our Delivery (median lead time fell from 28.7 days to 21 days after introduction of ultrasound) and both Quality metrics (proportion of GCA with positive TAB/TAUS increased from 29% to 69%; total prednisolone dose for not-GCA fell from 1.335g to 0.846g).Table 1.Concordance between temporal and axillary artery ultrasound (TAUS) and temporal artery biopsy (TAB) in scans performed through 2019. Cohen’s weighted kappa 0.59 (including equivocal results as separate category).TAUS positiveTAUS negativeTAUS equivocalTAB positive1411TAB negative5275TAB equivocal030Within Costs, average per-patient costs of TAB/TAUS declined from £1004/patient to £792/patient, but total referrals for TAB/TAUS increased from 6/month to 10/month, increasing overall costs. Staff and patient feedback (Service, Morale) revealed that further improvements to the care pathway were needed to manage the additional complexity.Conclusion:Lean methodology identified multiple metrics for evaluating the impact of TAUS on our service. Introducing TAUS improved Delivery and Quality, but measuring Costs, Morale and Service helped identify unintended consequences. Concordance between TAUS and TAB was good. We plan to continue to improve and monitor the care pathway based on our multi-stakeholder feedback.References:[1]Luqmani et al., HTA 2016[2]Mukhtyar et al., Clin Rheum 2019Disclosure of Interests:Sarah Mackie Grant/research support from: Roche (attendance of EULAR 2019; co-applicant on research grant), Consultant of: Sanofi, Roche/Chugai (monies paid to my institution not to me), Andrew Barr: None declared, Alison Cracknell: None declared, Shannon Farrell: None declared, Jimmy Parvin: None declared, Ajay Patil: None declared, Ian Simmons: None declared, Kate Smith Grant/research support from: Medical education grants from Sanofi and Biogen, Speakers bureau: Novartis, Andrea Sweeting: None declared, Max Troxler: None declared, Tara Webster: None declared, Richard Wakefield Speakers bureau: Novartis, Janssen, GE

IMPACT OF EDUCATIONAL ATTAINMENT ON WORKERS’ INCOMES

2021 ◽  
Vol 562 (1) ◽  
pp. 18-23
Author(s):  
Władysław Bogdan Sztyber
Keyword(s):  
Higher Education ◽  
European Union ◽  
Secondary Education ◽  
Income Level ◽  
Individual Member ◽  
The European Union ◽  
Member States ◽  
Level Of Education ◽  
The Impact ◽  
Oecd Data

The article presents the impact of the level of education of employees on their income in various terms. One of them is a study based on the OECD data from 2004–2005, which shows the differentiation of incomes of employees with different levels of education on the basis of the relative differentiation between them, assuming the income level of employees with upper secondary education as 100 and referring to it respectively the income level of employees with higher education and the level of income of employees with lower secondary education. The article then presents a more elaborate study of the impact of the level of education of employees on their incomes in the European Union, included in the Report “The European Higher Education Area in 2015”. This survey shows the impact of the education level of employees on the median of their gross annual income in the European Union and in the individual Member States. The article also compares the income differentiation depending on the level of education, based on the OECD data for 2004–2005, with the results of surveys on European Union Member States in 2010 and 2013.

scholarly journals The importance of hydrological uncertainty assessment methods in climate change impact studies

2014 ◽  
Vol 18 (8) ◽  
pp. 3301-3317 ◽  
Author(s):  
M. Honti ◽  
A. Scheidegger ◽  
C. Stamm
Keyword(s):  
Climate Change ◽  
Climate Change Impact ◽  
Hydrological Model ◽  
Uncertainty Assessment ◽  
Assessment Method ◽  
Calibration Data ◽  
Relative Importance ◽  
Impact Studies ◽  
Uncertainty Sources ◽  
Change Impact

Abstract. Climate change impact assessments have become more and more popular in hydrology since the middle 1980s with a recent boost after the publication of the IPCC AR4 report. From hundreds of impact studies a quasi-standard methodology has emerged, to a large extent shaped by the growing public demand for predicting how water resources management or flood protection should change in the coming decades. The "standard" workflow relies on a model cascade from global circulation model (GCM) predictions for selected IPCC scenarios to future catchment hydrology. Uncertainty is present at each level and propagates through the model cascade. There is an emerging consensus between many studies on the relative importance of the different uncertainty sources. The prevailing perception is that GCM uncertainty dominates hydrological impact studies. Our hypothesis was that the relative importance of climatic and hydrologic uncertainty is (among other factors) heavily influenced by the uncertainty assessment method. To test this we carried out a climate change impact assessment and estimated the relative importance of the uncertainty sources. The study was performed on two small catchments in the Swiss Plateau with a lumped conceptual rainfall runoff model. In the climatic part we applied the standard ensemble approach to quantify uncertainty but in hydrology we used formal Bayesian uncertainty assessment with two different likelihood functions. One was a time series error model that was able to deal with the complicated statistical properties of hydrological model residuals. The second was an approximate likelihood function for the flow quantiles. The results showed that the expected climatic impact on flow quantiles was small compared to prediction uncertainty. The choice of uncertainty assessment method actually determined what sources of uncertainty could be identified at all. This demonstrated that one could arrive at rather different conclusions about the causes behind predictive uncertainty for the same hydrological model and calibration data when considering different objective functions for calibration.

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