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This study evaluated pesticide exposure practices, and the potential health risks of drinking water and consuming fish from the cultivated wetlands of Ndop, Cameroon. Six hundred and twenty-six questionnaires were conveniently administered to farmers (≥ 26 years old) in a cross-sectional study to assess exposure practices and dietary risks. The Chi-square and Pearson correlation coefficients were used to establish relationships between variables. The PRIMET model was used to predict a worst-case dietary risk. The pesticide handling practices of 90% of farmers were inadequate. Chlorpyriphos, lambda-cyhalothrin, fipronil, and paraquat dichloride posed a possible dietary risk at recommended and applied doses, with chlorpyrifos having the highest exposure toxicity ratio (ETRdiet = 36.72). Paraquat dichloride, fipronil, and lambda-cyhalothrin posed a possible dietary risk at 26.3%, 58.3%, and 62.2% of their recommended concentrations, respectively. Remarkably, the dietary risk for cypermethrin was acceptable at 5.8 times its recommended dose (ETRdietR = 0.29). The significant positive correlation (p = 0.000) between PECfish and ETRdiet, suggests a possible health risk of consuming fish and drinking water harvested from the wetlands, thus the need for replacing pesticides posing possible risks at lower or recommended concentrations with less toxic alternatives and to train farmers on pesticide application practices. [ABSTRACT FROM AUTHOR]

The use of magnetic metasurfaces in Wireless Power Transfer systems is becoming a popular research topic: they have proven to be a valid approach to increase the performances (in terms of power transfer) and improve the overall EMC properties in terms of field emissions. In this contribution, the authors investigate the susceptibility of such systems in case of an impinging Electromagnetic Interference (that might also be intentional), evaluating different parameters for a selected set of the system's components. In particular, the worst‐case scenarios of voltage peak, energy and sharpness (where appliable) at the transmitting and receiving ports and at each capacitor of the metasurface are calculated. The results obtained for a specific system practically implemented in the lab, show that the metasurface does not necessarily decreases susceptibility towards EMI and it can be itself the most critical component. The identification of the key and critical parameters allows us to provide an insight on how metamaterials used as shielding devices should be properly designed. [ABSTRACT FROM AUTHOR]

Aim: To describe and compare the peak physical demands through the worst-case scenario method (WCS), according to different rolling average (RA) time epochs (i.e. 1 min, 3 min, and 5 min) and contextual variables in women soccer players. Methods: Using an observational-comparative study design, an elite women soccer team from the Spanish 1st league division was monitored during 27 matches. Nine WCS-dependent variables were assessed, including total distance (TD), high-speed running distance (HSR), sprint distance (SP), acceleration, and deceleration distance at different intensities by players position (i.e., central defenders [CD], wide defenders [WD], central midfielders [CM], wide midfielders [WM], forwards [F]), match half, location, and match outcome. Results: The 1-min RA showed the lowest variability (CV = 9.8–65.8%) for all nine dependent variables. The WD presented the highest TD (168 ± 15.71 m/min). Differences between positions were observed for: CM

This study analysed the periods in which the most demanding passages (MDP) of play occurred during professional soccer matches, considering different criterion variables and investigating the effect that the playing position had on the MDP-of-play occurrence for each criterion variable. The MDP of play were calculated based on five criterion variables: distance covered (DIS), sprinting distance (SPD), high-metabolic load distance (HMLD), and the total of high-intensity accelerations and decelerations (ACCHIGH and DECHIGH). The results showed that the first period of the match (0ʹ-15ʹ) was the interval with the highest frequency (i.e., the greatest % of cases) in which the players achieved the MDP of play for all the variables (DIS= 38.9%; SPD= 28.4%; HMLD= 37.7%; ACCHIGH= 54.3%; DECHIGH= 48.8%). The playing position had no significant effect on MDP-of-play occurrence in any variable (likelihood ratio, LR= 15.88–32.05; p > 0.05; effect size, ES= 0.01–0.04), except for the DIS covered (LR= 32.05; p= 0.04; ES= 0.05), in which the most frequent MDP for the full backs occurred within the second period of the match (15ʹ-30ʹ). In conclusion, the first periods of the matches usually elicited the MDP of play and these periods need to be trained to prevent injuries and optimize performance. [ABSTRACT FROM AUTHOR]

Catastrophic hyper-concentrated flow during the glacial lake outburst flood (GLOFs) and its far-reaching consequences on life, property and infrastructure are the foremost concern throughout the high mountain areas. The present investigation focuses on a potentially dangerous moraine-dammed proglacial lake in the Bhilangna Valley, central Himalaya, India, which has been expanding at an alarming rate during the last two decades. This lake has expanded from ~0.15 to ~0.35 km2 during 1999–2020 at the cost of loss in the associated glacier area by ~0.21 km2 during the same time period. We have tried to understand the possible trigger and simulated the worst-case outburst scenario and its impact on the settlements and infrastructure in the downstream valley. Two breaching scenarios: (1) overtopping and (2) piping which may be caused by the ice calving into the lake or through avalanches, have been generated, and a maximum possible discharge amount of ~4377 cumec has been estimated considering the lake depth as 30 m. The discharge can inundate an area of ~19 km2 along the river channel with a mean water depth of ~38 m and an average velocity of ~16 m/s. The MODIS-based land surface temperature analysis from 2002 to 2020 suggests that ~19% of the total area of the Bhilangna Basin has biennial surface temperature <0°C, indicating possible permafrost zone. Both the temperature analysis and the surface features surrounding the lake suggest the region to be dominated by permafrost. [ABSTRACT FROM AUTHOR]

Understanding the most demanding scenarios of basketball match-play can optimise training prescription. We established physical demand differences in total distance covered, distance covered at high-speed running, distance covered at high-intensity accelerations and decelerations, number of high-speed running actions and number of high-intensity accelerations comparing the traditional average method with the most demanding scenarios based on 1-minute rolling averages. Physical demand parameters were analysed from 21 elite basketball players according to playing position during a friendly game via local positioning system microtechnology. The results showed that players covered a total distance of 141.3 m·min−1 (p < 0.001; ES = 7.80) and 25.4 m·min−1 (p < 0.001; ES = 4.52) at high-speed running using rolling averages, compared to 66.3 and 3.2 m min−1, respectively, using the traditional average approach. These data represent a very large increase of 113.1% for total distance per minute and 686.4% for high-speed running distance per minute, 252% for the number of high-intensity accelerations and 290.5% for the number of high-intensity decelerations, respectively, demonstrating the relevance of this novel approach. In conclusion, this investigation indicated that the traditional average method underestimates peak physical demands over a 1-minute period during a basketball game. Thus, the average approach should be complemented by analysing the most demanding scenarios in order to have a better understanding of physical demands during basketball competition. [ABSTRACT FROM AUTHOR]

The objective of this article is to critically examine the regulatory framework associated with reclamation bonding mechanism in Indonesia. It suggests that the failure of the Indonesian reclamation bonding mechanism is due to a lack of regulatory clarity and the consequent weaknesses in law enforcement. In this context, this article reviews the existing literature on policy models pertaining to bonding mechanisms before arriving at the conclusion that the worst-case scenario described by Costanza and others (2015) represents the most apt remedy to improve Indonesia's reclamation bonding mechanism policy. Under a worst-case scenario bonding mechanism, the bond value is set up according to the costs associated with the most extensive probable environmental destruction. Such costs are over and above those associated with identified environmental damage. Companies intending to conduct mining activities are required to provide such a bond upfront, prior to commencing their exploration and operation–production. [ABSTRACT FROM AUTHOR]

The tolerance of machine parts working together is of great importance in terms of both functionality and cost. Especially, determining narrow tolerance ranges for machine parts produced by machining causes high cost increases. For this reason, it is desired to be able to assemble machine parts that will work with each other and to be produced with the widest possible tolerance range. In this study, an assembly system formed by combining standard machine elements on a shaft is analyzed. The manufacturers produce standard machine elements within a certain tolerance value range. In this direction, tolerances for a shaft were performed based on the tolerances of standard machine elements. This merging process started with the worst-case scenario and continued with Monte Carlo simulation to extend the tolerance range. As a result of the analysis, the tolerance value of ± 0.015 mm obtained in the worst-case scenario was expanded up to ± 0.27 mm with Monte Carlo simulation. In this way, it is possible to use a much wider tolerance range in the same mounting system and at the same time gain a benefit in cost. [ABSTRACT FROM AUTHOR]

The radiation environment in space is a complex mixture of particles of solar and galactic origin with a broad range of energies. In astronaut dose estimation, three sources must be considered: galactic cosmic radiation, trapped particles, and solar energetic particles (SEPs). The astronaut dose due to SEP exposure during a space mission is more difficult to estimate than the other components because the occurrence of a large solar particle event cannot be predicted by the current space weather research. Thus, several models have been proposed to estimate the worst-case scenario and/or the probability of the integral SEP fluence during a particular space mission, considering the confidence level, solar activity, and duration of the mission. In addition, recent investigations of the cosmogenic nuclide concentrations in tree rings and ice cores have revealed that the sun can cause solar particle events much larger than the largest event recorded in the modern solar observations. If such an extreme event occurs during a mission to deep space, astronauts may suffer from radiation doses in excess of the threshold value for some tissue reactions (0.5 Gy) and their career limit (0.6–1.2 Sv). This article reviews the recent progress made in space weather research that is useful for cosmic radiation dosimetry. [ABSTRACT FROM AUTHOR]

Container terminals play a critical role in maritime supply chains. However, they show vulnerabilities to severe weather events due to the sea-land interface locations. Previous severe weather risk analysis focused more on larger assessment units, such as regions and cities. Limited studies assessed severe weather risks on a smaller scale of seaports. This paper aims to propose a severe weather-induced container terminal loss estimation framework. Based on a container terminal operation simulation model, monthly average loss and single event-induced loss are obtained by using historical hazard records and terminal operation records as model inputs. By studying the Port of Shenzhen as the case study, we find that the fog events in March lead to the longest monthly port downtime and the highest monthly severe weather-induced economic losses in the studied port. The monthly average loss is estimated to be 30 million USD, accounting for 20% of the intact income. The worst-case scenario is found to be a red-signal typhoon attack which results in nearly 20% decrease in the month's income. The results provide useful references for various container terminal stakeholders in severe weather risk management. [ABSTRACT FROM AUTHOR]

The paper is a follow-up of the recent study on the assessment of discrete wind gust parameters impacting a flexible lightweight structure as a first step towards the evaluation of the worst-case scenario caused by strong wind gusts (JWEIA 231, 105207, 2022). The present study goes beyond by suggesting an optimization framework which allows to determine the worst-case scenario automatically. For this purpose, a stochastic response surface algorithm with a surrogate model based on radial basis functions is chosen. The algorithm relies on costly evaluations of the objective function, which consist of CPU-time intensive fully coupled fluid–structure interaction (FSI) high-fidelity simulations including the pre- and post-processing of the results. Besides the parallelization of the coupled FSI solver, a parallel version of the optimization algorithm allows to carry out several costly evaluations simultaneously. The Metric Stochastic Response Surface algorithm determines the worst case fast. Then, it continues to explore the optimization space to ensure that the global extremum is reached. A sensitivity study on relevant parameters of the optimization algorithm is conducted. Typically, for the present FSI setup, an optimization run takes one week with 6 evaluations in parallel to compute 100 different configurations. The worst case is found after about one third of the evaluations. The increase of parallel evaluations drastically reduces the wall-clock time, but the worst case is found later after half of the evaluations. This later finding is due to the parallel nature of the algorithm. Finally, the various sources of uncertainties that arise throughout the entire procedure are assessed and discussed. • Methodology to find the worst-case scenario of flexible structures under gust load. • Surrogate-based optimization algorithm to minimize costly FSI simulations. • High-fidelity fluid and structure modeling to capture transient effects. • Deterministic discrete gust model for a total control of its shape. • Application on a air-inflated flexible membrane in a turbulent boundary layer. [ABSTRACT FROM AUTHOR]

• Upper bound of field-induced overvoltage peak in power line network could be assessed both numerically and analytically. • Complex power line system could be equally represented by its coupling-dominate branch for assessing the overvoltage peak. • Specific segment lengths do not influence the predicted upper bound. • Relative orientation between adjacent line segments has strong impact on the upper bounds. This paper deals with the assessment of the maximal peak of the overvoltage induced in a power-line network due to the field-to-wire coupling from an external electromagnetic disturbance. A worst-case analysis is here combined with the transmission line model to find the terminal overvoltage, induce by radiated electromagnetic disturbances of constrained energy density and bandlimits. The approach was applied to canonic power line network topologies, from statistic viewpoint, it is demonstrated that dominant coupling can be ascribed to the branch containing the most twisted segments. Accordingly, efforts have been devoted to find analytical solution to overvoltage peak upper bound for the coupling-dominant zigzag branch. In this connection, both versatile implicit solution and approximated explicit expressions of the upper bound are formulated, which reveals the relations between the upper bound of zigzag branch and its segments, quantitively interpreting the effect of segment orientations and length. Finally, numerical simulations corroborate the model validity and suggest that the estimations of upper bound are sufficiently accurate for analyzing practical power line network. This proposed approach will be instructive for power system insulation coordination and protection design. [ABSTRACT FROM AUTHOR]

Seaports are critical infrastructure systems in the international economy. They are at the same time vulnerable to various types of natural and man-made catastrophes due to their special coastal and low-lying locations. Traditional catastrophe risk analyses focused more on regions, port cities, and port communities. Limited studies assessed catastrophe risks on ports as a specific system. This paper aims to develop a catastrophe-induced port loss estimation framework, based on a port operation simulation model, actual terminal records and historical hazard records. By using the typhoon hazard and the Port of Shenzhen as a case study, we find that (1) the worst-case scenario of a typhoon impact could cause a total loss of US$0.91 billion for a terminal with 16 berths; and (2) the annual predicted typhoon-induced loss for the same terminal for the next 5 years will reach approximately US$64 million, accounting for 19.7% of the terminal net profit in 2015. The results provide useful references for various port stakeholders in catastrophe risk assessment and mitigation. [ABSTRACT FROM AUTHOR]

We present results of calculations of the ultimate forces for the worst-case scenario, an important safety concern in hybrid magnets. They appear during a simultaneous and immediate burnout of some or all upper or lower resistive coil halves, or shorts between the coils in themid-plain. Because of their intensity, they have a dramatic impact on the mechanical layout of a hybrid magnet. An electromagnetic shield between insert and outsert, as it is the case for the Grenoble hybridmagnet, takes up part of these forces and reduces them considerably. It makes the calculation of the now time dependent forces rather complex. The ultimate forces have been calculated for two models: a) conservation of magnetic flux with instantaneous energy transfer from the shorted coils to the remaining parts, and b) conservation of energy of the whole hybrid system, including the power supplies, with energy transfer via mutual axial and radial coupling to the other coils. Only for case a) we find an instantaneous force of 6 MN between resistive magnet and its housing at t = 0. The maximum force between resistive magnet and shield appears, when the resistive power supply is switched off at t = 50/100 ms: it is 3.7 MN/4.4 MN for case a) against only 1.5 MN for b). The force on the superconducting magnet is reduced from 210 kN for a) to 130 kN for b). The results underline the usefulness of a shield between insert and outsert to reduce their electrodynamic interaction. They also confirm that the Grenoble hybrid magnet is well suited for inserts of much higher power levels. Our findings have also consequences for the layout of hybrid magnets without shield. [ABSTRACT FROM AUTHOR]

In this study, the authors propose a control structure for a class of linear time‐invariant (LTI) systems with Lipschitz non‐linearity and unknown time‐varying input delay. This scheme considers the worst‐case scenario in control design with truncated prediction feedback approach, and takes into account the information of the lower bound of delay in the stability analysis. A finite‐dimensional controller is constructed, requiring neither the non‐linear function nor the exact delay function. The truncated prediction deviation is minimised by employing the delay range, and then bounded by integral construction and related techniques. Within the framework of Lyapunov–Krasovskii functionals, sufficient delay–range‐dependent conditions are derived for the closed‐loop system to guarantee the global stability. Two numerical examples are given to validate the proposed control design. [ABSTRACT FROM AUTHOR]

The implementation of inappropriate land use planning has negative impact on environmental quality, threatens food, health and residential security, and can even lead to regional environmental disaster. In this paper, a worst-case scenario based methodology using the land use environmental tolerance index (LETI) was proposed to assess the impact of land use planning on the environment. The land use planning environmental impact assessment (LUPEA) of Lianyungang City was performed as a case study to demonstrate the novel methodology. The inappropriate land use planning of the study area was spatially identified, and adjustments for the land use planning scheme to minimize the adverse impacts were accordingly recommended. Results show that the land use planning layout of the study area is fundamentally rational as most of the planned production and living land parcels are located outside the worst-case scenario areas, but the small fraction of the parcels in the worst-case scenario areas indicates a need for an improved land use planning scheme. This methodology provides a new perspective to evaluate the impact of land use planning on the environment, especially for densely populated countries which still suffer food, health and residential security issues and thus require much attention to environmental safety. [ABSTRACT FROM AUTHOR]

Real-time hybrid simulation (RTHS) allows researchers to physically evaluate critical parts of a prototype structure at full scale in the laboratory while the rest is numerically modeled. The reliability of the RTHS experimental results however still remains unsolved in the presence of experimental errors even though a number of methods have been proposed based on the actuator tracking in the time domain. Frequency-domain evaluation indices (FEI) provide a novel and effective technique to evaluate the amplitude and phase errors of the actuator tracking. In this paper, the correlation between the reliability of RTHS results and the FEI indices is explored for the worst-case scenarios of single-degree-of-freedom (SDOF) linear elastic structures. The influence of natural frequency and damping ratio are considered through a suite of ground motions. The relationship between the FEI parameters and the error of RTHS replicating actual structural response is explored and a criterion based on worst-case scenarios is proposed for reliability assessment. Numerical simulations are conducted to demonstrate the effectiveness of the proposed reliability criterion. [ABSTRACT FROM AUTHOR]

The authors present new results regarding the analysis of voltage transients induced by switching capacitors in power delivery systems. Their approach is based on a systematic technique that facilitates the computation of initial conditions when the switch occurs. This set‐up permits an efficient parametric exploration that is suitable for accomplishing safe voltage peaks according to customer specifications. The authors discuss upper and lower bounds corresponding, respectively to (i) the worst‐case scenario in a lossless system, and (ii) the damped case with a shunt load and equivalent series resistances. Experimental measurements corroborate the underlying principles and results presented in this study. [ABSTRACT FROM AUTHOR]

We derive worst-case scenarios in a life insurance model in the case where the interest rate and the various transition intensities are mutually dependent. Examples of this dependence are that (a) surrender intensities and interest rates are high at the same time, (b) mortality intensities of a policyholder as active and disabled, respectively, are low at the same time, and (c) mortality intensities of the policyholders in a portfolio are low at the same time. The set from which the worst-case scenario is taken reflects the dependence structure and allows us to relate the worst-case scenario-based reserve, qualitatively, to a Value-at-Risk-based calculation of solvency capital requirements. This brings out perspectives for our results in relation to qualifying the standard formula of Solvency II or using a scenario-based approach in internal models. Our results are powerful for various applications and the techniques are non-standard in control theory, exactly because our worst-case scenario is deterministic and not adapted to the stochastic development of the portfolio. The formalistic results are exemplified in a series of numerical studies. [ABSTRACT FROM AUTHOR]

The paper is a step towards the evaluation of the worst-case scenario caused by strong wind gusts impacting civil engineering air-inflated lightweight structures. These extreme events with short durations but high strengths are responsible for short-term highly instantaneous loads endangering the structural integrity of the design. For this purpose, a generic test case is defined which includes a discrete wind gust model, the approaching turbulent boundary layer and a flexible structure exposed to the resulting fluid flow. The simulation framework relies on a partitioned coupled solver for fluid–structure interaction extended by two source-term formulations which allow to inject the wind gusts as well as the background turbulence. To save CPU time, a part of the investigations is conducted for the rigid case as a physical meta-model. The particularly critical cases found in this way were examined for the case of the flexible structure. Under varying system parameters such as the strength, length and position of the gust the following objective functions are evaluated: Force coefficients, maximal deflections and local inner stresses. The worst case occurs for maximal gust strength and length, when the gust hits the membrane at half height. Furthermore, the effect of the superposition of the discrete gust with background turbulence is analyzed for two scenarios. The gust is first superimposed to different inflow turbulences of the same intensity leading to non-negligible deviations of force coefficients and deflections. Second, the level of the turbulence intensity is successively increased up to a factor of five showing only a minor effect on the flexible structure not generating a new worst case. • Towards the worst-case scenario of material failure caused by discrete wind gusts. • Civil engineering application based on an air-inflated lightweight structure. • Simulation framework based on a partitioned coupled LES-solver for FSI. • Assessment of discrete wind gust parameters (strength, length, position). • Evaluation of force coefficients, maximal deflections and local inner stresses. [ABSTRACT FROM AUTHOR]

The decision-making on portfolio investment is fundamental in the financial market, but getting the optimal strategy is challenging due to high uncertainty and massive noise in the market. Deep Deterministic Policy Gradient (DDPG), proposed by Lillicrap et al. (2015), is a deep Reinforcement Learning (RL) algorithm that made remarkable achievements in the financial perspective. Although the applications of RL in financial trading are well-developed, it is surprising that most of the literature ignores the possible risk of rare occurrences of catastrophic events and the effect of the worst-case scenarios on trading decisions. In this paper, we first develop a novel deep RL algorithm, called Hierarchical DDPG, that combines the classical DDPG algorithm and the Hierarchical RL structure to control the risk of portfolio investment. Second, we adapt the distributional DDPG method for portfolio management problems, which aims to maximize the α - percentile expectation based on the distribution of future returns. A real world dataset is used to validate the performance of our proposed models. The experimental results show that our proposed models outperform the market and classical DDPG, and moreover, both approaches provide effective methods of constructing a risk-sensitive policy to protect investors from suffering a huge loss. • Risk-sensitive policies can avoid the effect of the crisis in the financial market. • The hierarchical deep learning algorithm is developed to control the portfolio risk. • The distributional learning method is proposed for risk-averse trading policies. • The study shows our proposed models effectively protect investors from a large loss. [ABSTRACT FROM AUTHOR]

In this paper, we establish several relations between convex order, variance order, and comonotonicity. In the first part, we extend Cheung (2008b) to show that when the marginal distributions are fixed, a sum with maximal variance is in fact a comonotonic sum. Thus the convex upper bound is achieved if and only if the marginal variables are comonotonic. Next, we study the situation where besides the marginal distributions; the variance of the sum is also fixed. Intuitively one expects that adding this information may lead to a bound that is sharper than the comonotonic upper bound. However, we show that such upper bound does not even exist. Nevertheless, we can still identify a special dependence structure known as upper comonotonicity, in which case the sum behaves like a convex largest sum in the upper tail. Finally, we investigate when the convex order is equivalent to the weaker variance order. Throughout this paper, interpretations and significance of the results in terms of portfolio risks will be emphasized. [ABSTRACT FROM AUTHOR]

Abstract: The 2006 dual Pingtung earthquake event and the 2004 South Asia tsunami highlighted the potential tsunami hazards from Manila trench. Manila trench is only about 100km away from Taiwan, therefore one shall punctuate the importance of thorough study on all possible tsunami scenarios for hazard mitigation. Based on the faults parameters issued by USGS and the seismic record from Global CMT, this study creates a hypothetical earthquake tsunami scenario caused by seismic motion at Manila trench. The magnitude of the earthquake is 9.35 (M w), the total length is 990km, and the maximum initial free-surface height is 9.3m. The initial displacement profile is provided in this paper. An open source code, COMCOT, is adopted to perform the simulation of the tsunami propagation, runup, and inundation around Taiwan. Nested grid system and moving boundary technique are adopted to study runup and inundation. The result shows that the maximum wave height is 11m in southern Taiwan. Serious flooding is observed in the southwest coast of Taiwan. Tsunami inundation is able to reach 8.5km inlandward. Due to the refraction effect, 8m wave height is noted in the northeast coast of Taiwan. The detailed tsunami behavior around Taiwan is described in the context. [Copyright &y& Elsevier]

Abstract: As a first step towards the development of inundation maps for the northwestern Indian Ocean, we simulated the near-field inundation of two large tsunami in the Makran subduction zone (MSZ). The tsunami scenarios were based on large historical earthquakes in the region. The first scenario included the rupture of about 500km of the plate boundary in the eastern MSZ, featuring a moment magnitude of Mw 8.6. The second scenario involved the full rupture of the plate boundary resulting from a Mw 9 earthquake. For each scenario, the distribution of tsunami wave height along the coastlines of the region is presented. Also, detailed runup modeling was performed at four main coastal cities in the region for the second scenario. To investigate the possible effect of splay fault branching on tsunami wave height, a hypothetical splay fault was modeled which showed that it can locally increase the maximum wave height by a factor of 2. Our results showed that the two tsunami scenarios produce a runup height of 12–18m and 24–30m, respectively. For the second scenario, the modeled inundation distance was between 1 and 5km. [Copyright &y& Elsevier]

Worst-case scenario optimization deals with the minimization of the maximum output in all scenarios of a problem, and it is usually formulated as a min-max problem. Employing nested evolutionary algorithms to solve the problem requires numerous function evaluations. This work proposes a differential evolution with an estimation of distribution algorithm. The algorithm has a nested form, where a differential evolution is applied for both the design and scenario space optimization. To reduce the computational cost, we estimate the distribution of the best worst solution for the best solutions found so far. The probabilistic model is used to sample part of the initial population of the scenario space differential evolution, using a priori knowledge of the previous generations. The method is compared with a state-of-the-art algorithm on both benchmark problems and an engineering application, and the related results are reported. [ABSTRACT FROM AUTHOR]

This article proposes the application of the maximum-entropy principle (MEP) to agency contracting (where a principal hires an agent to make decisions on their behalf) in situations where the principal and agent only have partial knowledge on the probability distribution of the output conditioned on the agent's actions. The paper characterizes the second-best agency contract from a maximum entropy distribution (MED) obtained from applying the MEP to the agency situation consistently with the information available. We show that, with the minimum shared information about the output distribution for the agency relationship to take place, the second-best compensation contract is (a monotone transformation of) an increasing affine function of output. With additional information on the output distribution, the second-best optimal contracts can be more complex. The second-best contracts obtained theoretically from the MEP cover many compensation schemes observed in real agency relationships. [ABSTRACT FROM AUTHOR]

Based on Markowitz mean-variance theoretical model (MV), the energy portfolio optimization problem has been extensively studied to obtain the optimal strategies of energy resource allocations and achieve the efficient usages and productions of energy. However, MV leads to the optimal energy portfolios infeasible without consideration of uncertainties. Meanwhile, dealing with the uncertain input parameters in the model, robust mean-variance model (RMV-worst) can overcome this shortcoming, but the optimal energy portfolio performances are considerably inferior. Therefore, contrary to RMV-worst, this paper analytically constructs an alternative robust portfolio model (RMV-best). Furthermore, from the energy stock market of China the data containing two motion cycles is divided into three movement statuses to verify the overall performances of the optimal energy portfolios. Finally, the comparison results add to the existing researches on energy portfolio optimization by: (i) RMV-best can validly improve the energy portfolio performances while ensuring the optimal energy portfolios feasible. (ii) The different movement statuses significantly influence on the energy portfolio performances, subsequently giving the favorable decisions of energy portfolios. (iii) The optimal energy portfolios of RMV-best are very reliable, as further indicates that RMV-best can bring about the convincing energy portfolios. • Best-case scenario robust model is built, improve energy portfolio performances. • The movement statuses of stock market influence on the energy portfolio selection. • The more favorable energy portfolios can be obtained for each movement status. • Wide application of RMV-worst is inefficient and undesirable for energy portfolio. • The optimal energy portfolios of RMV-best are reliable and profitable. [ABSTRACT FROM AUTHOR]