Prediction of Cross-Shore Beach Profile Evolution in the Vicinity of Seawalls

2011 ◽  
Author(s):  
Seyed Ahmad Lashteh-Neshaei ◽  
Mohammad Ali Lotfollahi-Yaghin ◽  
Morteza Biklaryan
Keyword(s):  
Present Model ◽  
Theoretical Models ◽  
Measured Data ◽  
Probability Density Functions ◽  
Density Functions ◽  
Beach Profile ◽  
Short Term ◽  
New Approach ◽  
Proposed Model ◽  
Measured Probability

Although there exist advanced models which predict to beach profile for natural beaches, the behavior of the beaches in front of seawalls still suffers from the lack of appropriate theoretical models and sufficient measured data. Following the results obtained from the measurements, a beach profile evolution model is developed, using the measured probability distribution of the near-bed horizontal velocities as input, to predict the short-term bed level changes in the vicinity of e partially reflective seawall. The present model introduces a new approach in which based on integrating the probability density functions of the near-bed horizontal velocities, the sediment displacements and consequently bed level changes are calculated in front of a partially reflective structure. The results obtained from the model and comparison with the experiments are promising and encouraging for further developments of the proposed model.

Probabilistic Optimal Design Using Successive Surrogate Probability Density Functions

1990 ◽  
Author(s):  
R. J. Eggert ◽  
R. W. Mayne
Keyword(s):  
Probability Density ◽  
Optimization Method ◽  
Probability Density Functions ◽  
Density Functions ◽  
Matching Method ◽  
Design Constraint ◽  
New Approach ◽  
Function Formulation ◽  
The Moment ◽  
Theoretical Considerations

Abstract Probabilistic optimization using the moment matching method and the simulation optimization method are discussed and compared to conventional deterministic optimization. A new approach based on successively approximating probability density functions, using recursive quadratic programming for the optimization process, is described. This approach incorporates the speed and robustness of analytical probability density functions and improves accuracy by considering simulation results. Theoretical considerations and an example problem illustrate the features of the approach. The paper closes with a discussion of an objective function formulation which includes the expected cost of design constraint failure.

An Approach to the Intermediate State of the Distributed Internal Fields on Muon Site

2019 ◽  
Vol 966 ◽  
pp. 476-482
Author(s):  
Muhamad Darwis Umar ◽  
Isao Watanabe
Keyword(s):  
Intermediate State ◽  
Muon Spin ◽  
Golden Rule ◽  
Probability Density Functions ◽  
Density Functions ◽  
New Approach ◽  
High Tc ◽  
Muon Site ◽  
Spin Depolarization ◽  
Superconducting Oxides

We show a new approach to provide anaysis functions of the muon-spin depolarization in order to describe the intermediate state between Gaussian and Lorentzian behavior. The Kubo Golden Rule (KGR) formula was used to mix the Gaussian and Lorentzian probability density functions. The result confirmed that the KGR formula can analytically explain the intermediate states. The current study suggests a new approach to investigate the so-called pseudogap state of high-Tc superconducting oxides.

Alternative Environmental Contours for Marine Structural Design: A Comparison Study

2014 ◽  
Author(s):  
Erik Vanem ◽  
Elzbieta M. Bitner-Gregersen
Keyword(s):  
Structural Design ◽  
Joint Distribution ◽  
Traditional Approach ◽  
Physical Space ◽  
Probability Density Functions ◽  
Density Functions ◽  
Comparison Study ◽  
New Approach ◽  
Contour Lines ◽  
Wind Sea

A new approach to estimating environmental contours has recently been proposed, where the contours are estimated in the original physical space by Monte Carlo simulations from the joint distribution directly rather than applying the Rosenblatt transformation. In this paper, the new and the traditional approach to estimating the contours are presented and the assumptions on which they are based are discussed. The different results given by these two methods are then compared in a number of case studies. Simultaneous probability density functions are fitted to the joint distribution of significant wave height and wave period for selected ocean locations and, for each area, environmental contours are estimated for both methods. The chosen locations are characterised by different wave climates. Thus, the practical consequences of the choice of approach are assessed. Particular attention is given to mixed sea systems, i.e. a combination of wind sea and swell. In these situations, the new approach for environmental contours may fail to identify realistic conditions along some parts of the contours while for other wave conditions the contours are quite similar. The paper also briefly discusses possible ways of amending the new approach to estimating the contours to obtain more realistic conditions all along the contour lines.

A New Approach to Probability in Engineering Design and Optimization

1984 ◽  
Vol 106 (1) ◽  
pp. 5-10 ◽  
Author(s):  
J. N. Siddall
Keyword(s):  
Probability Density ◽  
Engineering Design ◽  
Probability Distributions ◽  
Probability Density Functions ◽  
Density Functions ◽  
New Approach ◽  
Design And Optimization ◽  
Evolutionary Technique ◽  
Probability And Statistics

The anomalous position of probability and statistics in both mathematics and engineering is discussed, showing that there is little consensus on concepts and methods. For application in engineering design, probability is defined as strictly subjective in nature. It is argued that the use of classical methods of statistics to generate probability density functions by estimating parameters for assumed theoretical distributions should be used with caution, and that the use of confidence limits is not really meaningful in a design context. Preferred methods are described, and a new evolutionary technique for developing probability distributions of new random variables is proposed. Although Bayesian methods are commonly considered to be subjective, it is argued that, in the engineering sense, they are really not. A general formulation of the probabilistic optimization problem is described, including the role of subjective probability density functions.

scholarly journals EXTREMAL STATISTICS OF STORM SURGES BY TYPHOON

1984 ◽  
Vol 1 (19) ◽  
pp. 8
Author(s):  
Yoshito Tsuchiya ◽  
Yoshiaki Kawata
Keyword(s):  
Probability Density ◽  
Return Period ◽  
Storm Surges ◽  
Probability Density Functions ◽  
Density Functions ◽  
Tidal Variation ◽  
New Approach ◽  
Probability Of Occurrence ◽  
Typhoon Track ◽  
Tidal Data

The objective of this paper is to propose a new approach based on the direction of the typhoon track for determining the probability of occurrence of extremal tides due to storm surges, as well as their return period. The study includes the effects of periods in tidal data and of tidal variation stemming from extensive reclamation along coasts on the fitness of the extremal data to probability density functions. The method is justified by application to an analysis of the probability of occurrence of storm surges in Osaka bay.

scholarly journals UMA ALTERNATIVA PARA CARACTERIZAR O VALOR DA CONDUTIVIDADE HIDRÁULICA EM SOLO SATURADO

Irriga ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. 54-60
Author(s):  
Maria Vilma Tavares de Moura ◽  
Paulo Rodolfo Leopoldo ◽  
Sérgio Marques Júnior
Keyword(s):  
Hydraulic Conductivity ◽  
Spatial Variability ◽  
Probability Density ◽  
Data Distribution ◽  
Rio Grande ◽  
Measured Data ◽  
Probability Density Functions ◽  
Density Functions ◽  
E Mail ◽  
Soil Spatial Variability

UMA ALTERNATIVA PARA CARACTERIZAR O VALOR DA CONDUTIVIDADE HIDRÁULICA EM SOLO SATURADO   Maria Vilma Tavares de MouraSecretaria da Agricultura e Abastecimento do Estado do Rio Grande do Norte Br 101 - Km 0 – Lagoa Nova - Fone: (084) 2311212 CEP 57075-050  -   Natal-RNPaulo Rodolfo LeopoldoFCA/UNESP – Depto. Engenharia Rural Fone: (014)8213883; Fax: (014) 8213438 CEP 18603-970 - Botucatu-SPSérgio Marques JúniorDepto. Engenharia Rural - CCA/UFSC Rodovia Admar Gonzaga, Km 03 - Itacorubi CEP 88037-500 - Florianópolis-SC - Fone: (048) 2341013 e-mail: [email protected]   1 RESUMO   O objetivo do presente artigo é apresentar um estudo sobre a variabilidade espacial da condutividade hidráulica do solo estimada em meio saturado, apresentando alternativas para caracterização de seu valor em uma determinada porção do solo. A partir de uma série de dados, verificou-se a existência de não normalidade na distribuição, justificando a utilização de outras funções de densidade de probabilidade para o estudo. Nesta situação, a distribuição dos dados amostrados apresentou bom ajuste às funções de densidade gama incompleta e beta.   UNITERMOS: Condutividade hidráulica, variabilidade espacial do solo, funções de densidade de probabilidade.   MOURA, M.V.T., LEOPOLDO, P.R., MARQUES JÚNIOR, S.M.AN ALTERNATIVE TO CHARACTERIZE THE HYDRAULIC CONDUCTIVITY IN SATURATED SOIL   2 ABSTRACT   The aim of this paper was to study the spatial variability of soil saturated hydraulic conductivity, offering an strategy to characterize its value in a set of soil. It was observed the occurrence of non-normal distribution, justifying the use of probability density functions. In this study, measured data distribution showed good fitting with incomplete gamma and beta distribution.    KEYWORDS: Hydraulic conductivity, soil spatial variability, probability density functions.

Uncertainties in Predictions by System Thermal-Hydraulic Codes: The CASUALIDAD Method

2014 ◽  
Author(s):  
A. Petruzzi ◽  
F. D’Auria
Keyword(s):  
Measured Data ◽  
Probability Density Functions ◽  
Density Functions ◽  
Uncertain Parameters ◽  
Adjoint Sensitivity ◽  
The Third ◽  
Model Predictions ◽  
Industrial Level ◽  
Sensitivity And Uncertainty Analysis ◽  
Selection Of

The present paper deals with the description of the salient features of three independent approaches for estimating uncertainties associated with predictions of complex system codes. The 1st approach is the “standard” one and the most used at the industrial level: it is based upon the selection of input uncertain parameters, on assigning related ranges of variations and, possibly, PDF (Probability Density Functions) and on performing a suitable number of code runs to get the combined effect of variation on the results. In the 2nd approach the uncertainty derives from the comparison between relevant measured data and results of corresponding code calculations. The 3rd approach is based on the Bayesian inference technique and on the availability of experimental data by which computer model predictions can be improved and the ranges of variation of (in theory) ‘all’ input parameters can be characterized. More details are provided in respect with the third approach that has been named CASUALIDAD (Code with the capability of Adjoint Sensitivity and Uncertainty AnaLysis by Internal Data ADjustment and assimilation).

NEARLY EXACT OPTION PRICE SIMULATION USING CHARACTERISTIC FUNCTIONS

2012 ◽  
Vol 15 (07) ◽  
pp. 1250047 ◽  
Author(s):  
CAROLE BERNARD ◽  
ZHENYU CUI ◽  
DON MCLEISH
Keyword(s):  
Characteristic Function ◽  
Probability Density ◽  
Option Price ◽  
Probability Density Functions ◽  
Heston Model ◽  
Characteristic Functions ◽  
Density Functions ◽  
New Approach ◽  
Black Scholes ◽  
Unbiased Estimates

This paper presents a new approach to perform a nearly unbiased simulation using inversion of the characteristic function. As an application we are able to give unbiased estimates of the price of forward starting options in the Heston model and of continuously monitored Parisian options in the Black-Scholes framework. This method of simulation can be applied to problems for which the characteristic functions are easily evaluated but the corresponding probability density functions are complicated.

Alternative Environmental Contours for Marine Structural Design—A Comparison Study1

2015 ◽  
Vol 137 (5) ◽  
Author(s):  
Erik Vanem ◽  
Elzbieta M. Bitner-Gregersen
Keyword(s):  
Monte Carlo ◽  
Structural Design ◽  
Significant Wave Height ◽  
Joint Distribution ◽  
Traditional Approach ◽  
Physical Space ◽  
Probability Density Functions ◽  
Density Functions ◽  
New Approach ◽  
Rosenblatt Transformation

A new approach to estimate environmental contours in the original physical space by direct Monte Carlo simulations rather than applying the Rosenblatt transformation has recently been proposed. In this paper, the new and the traditional approach to estimating the contours are presented and the assumptions on which they are based are discussed. The different results given by these two methods are then compared in a number of case studies. Simultaneous probability density functions are fitted to the joint distribution of significant wave height and wave period for selected ocean locations and environmental contours are estimated for both methods. Thus, the practical consequences of the choice of approach are assessed. Particular attention is given to mixed sea systems. In these situations, the two approaches to environmental contours may be very different while for other wave conditions the contours are similar.

scholarly journals Detecting Nuisance Calls over Internet Telephony Using Caller Reputation

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 353
Author(s):  
Ibrahim Tariq Javed ◽  
Khalifa Toumi ◽  
Fares Alharbi ◽  
Tiziana Margaria ◽  
Noel Crespi
Keyword(s):  
Security Risk ◽  
False Detection ◽  
Short Term ◽  
New Approach ◽  
Call Duration ◽  
Internet Telephony ◽  
Proposed Model ◽  
Different Types ◽  
Reputation Model

Internet telephony permit callers to manage self-asserted profiles without any subscription contract nor identification proof. These cost-free services have attracted many telemarketers and spammers who generate unsolicited nuisance calls. Upon detection, they simply rejoin the network with a new identity to continue their malicious activities. Nuisance calls are highly disruptive when compared to email and social spam. They not only include annoying telemarketing calls but also contain scam and voice phishing which involves security risk for subscribers. Therefore, it remains a major challenge for Internet telephony providers to detect and avoid nuisance calls efficiently. In this paper, we present a new approach that uses caller reputation to detect different kinds of nuisance calls generated in the network. The reputation is computed in a hybrid manner by extracting information from call data records and using recommendations from reliable communicating participants. The behavior of the caller is assessed by extracting call features such as call-rate, call duration, and call density. Long term and short term reputations are computed to quickly detect the changing behavior of callers. Furthermore, our approach involves an efficient mechanism to combat whitewashing attacks performed by malicious callers to continue generating nuisance calls in the network. We conduct simulations to compute the performance of our proposed model. The experiments conclude that the proposed reputation model is an effective method to detect different types of nuisance calls while avoiding false detection of legitimate calls.

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