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The aim of this study is to improve hydrocarbon reservoir estimation by combining the deterministic and probabilistic approaches in an improved volumetric model with the objective of reducing geological uncertainties and achieving better reserve estimations. The case study was made in the Rio Del Rey basin of Cameroon. To achieve this goal, a mathematical model was built using the volumetric expression of the stock tank original oil in place (STOIIP), the Raymer–Hunt expression of porosity and transit time, and the Simandoux model modified by the Schlumberger expression of water saturation. The application and validation of the proposed model were made through Interactive Petrophysics, Petrel software, and Monte Carlo simulation on Minitab Workspace. The results obtained by a deterministic approach on the investigated area of 2000 m2 give a total estimated quantity of oil in place of 11897.67 MMbbl, a total estimated quantity of gas in place of 27.79 Bcf, a total estimated quantity of recoverable oil of 3606.28 MMbbl, and a total estimated quantity of recoverable gas of 19.52 Bcf. The probabilistic approach permitted to obtain an estimated quantity of oil in place of 150194141.45 MMbbl. In this study, it appears that the net value added is $288,898,222. This therefore confirms the accuracy of the model and the profitability of the project. [ABSTRACT FROM AUTHOR]

The most common type of natural disaster is a landslide which impact millions of people and costing tens of thousands of lives and billions of dollars in damage every year. Earthquakes have the potential to trigger landslides of varying sizes in mountainous regions, endangering the residential communities situated at the base of the mountains. The earthquake impact on the slope stability during the subsequent rains is not considerable in certain regions where the earthquake impact is not high enough to produce major soil movement. However, in some Landslide prone regions, the stability of slopes that are impacted by subsequent rains is significantly influenced by massive fissures on the surface of the slopes that are generated by earthquake shaking. The coupling effect of these two factors can significantly reduce the stability and safety of slopes, leading to catastrophic consequences. This paper reviewed the response of slopes under the combined influence of rain and seismic loading. This critical review highlights the importance of integrating rainfall and earthquake parameters simultaneously in slope deformation studies. In addition to slope stability analysis, slope deformation analysis should also receive equal attention. Future directions of this research should be focused on developing robust models and algorithms to simulate and assess slope failures caused by earthquakes and heavy rainfall in light of technological advancements, improvement of computational efficiency. [ABSTRACT FROM AUTHOR]

A primary objective for the sustainable development of the maritime sector is to transition toward carbon-neutral fuels, with the aim to reduce emissions from maritime transportation. Ammonia emerges as a promising contender for hydrogen storage, offering the potential for CO2-free energy systems in the future. Notably, ammonia presents advantageous attributes for hydrogen storage, such as its high volumetric hydrogen density, low storage pressure requirements, and long-term stability. However, it is important to acknowledge that ammonia also poses challenges due to its toxicity, flammability, and corrosive nature, presenting more serious safety concerns that need to be addressed compared with other alternative fuels. This study sought to explore the dispersion characteristics of leaked gas during truck-to-ship ammonia bunkering, providing insights into the establishment of appropriate safety zones to minimize the potential hazards associated with this process. The research encompassed parametric studies conducted under various operational and environmental conditions, including different bunkering conditions, gas leak rates, wind speeds, and ammonia toxic doses. EFFECTS, which is commercial software for consequence analysis, was utilized to analyze specific scenarios. The focus was on a hypothetical ammonia bunkering truck of 37,000 L refueling an 8973 deadweight tonnage (DWT) service vessel with a tank capacity of 7500 m3 in the area of Mokpo Port, South Korea. The study's findings underscore that the ammonia leak rate, ambient temperature, and wind characteristics significantly impacted the determination of safety zones. Additionally, the bunkering conditions, leak hole size, and surrounding traffic also played influential roles. This study revealed that bunkering in winter resulted in a larger safety zone compared with bunkering in summer. The lethality dose of ammonia was affected by the leak hole size, time for dispersion, and the amount of ammonia released. These observed variations imply that ammonia truck-to-ship bunkering should be undertaken with carefully chosen suitable safety criteria, thereby significantly altering the scope of safety zones. Consequently, the risk assessment method outlined in this paper is expected to assist in determining the appropriate extent of safety zones and provide practical insights for port authorities and flag states contributing to the future sustainable development of the maritime industry. [ABSTRACT FROM AUTHOR]

In mountainous areas, snow avalanches could be triggered by the shaking produced by earthquakes. The forces induced by the earthquake can cause an irregular increase of shear strength load down the slope, for the presence of complex surface and buried morphologies. Topographic irregularities generate maximum effects of waves amplification linked to wavelengths comparable to the horizontal dimension of the topographic feature. For this reason, the selected time-histories represent an appropriate input for the two-dimensional numerical response analyses when a dynamic phenomenon produce the resonant motion of a whole mountain. This represents an important earthquake-induced hazard in snow-covered mountain areas with high probability of seismic events. Some valleys are located in regions with scare ground motion data and investments on infrastructures are not always accompanied by adequate protection against earthquake-induced avalanches. The paper points out a simple deterministic approach for selecting a set of real accelerograms applied to a real case of Siella Mountain (Central Italy) where a large avalanche destroying a tourist facility of Rigopiano resort on 18 January 2017. The selected time histories were used as input for the two-dimensional numerical model of the subsoil to evaluate the topographic seismic amplification in ridge and compare it with the results of other authors. These methods suggest that morphology-related inertial effects should be considered as an overload action on snow layers when controlling multi-hazard studies and spatial planning. [ABSTRACT FROM AUTHOR]

Road agencies commonly face high level complexity of comprehensive pavement maintenance scheduling complications. This could be due to uncertainty of some parameters that substance in the predicting models. Disregarding this uncertainty of such parameters in the road maintenance scheduling problems may lead to imprecise solutions and unreliable road conditions. Frequently time series data that have a hierarchical structure are used for predicting road surface or pavement structure distresses models. However, further realistic and accurate predicted models are those consider supplementary inconsistency between time series data with utilising a predictive approach that imposes knowledge of the input parameters. The purpose of this study is to test this theory by comparing the predictions of models developed using two approaches and their accuracies in utilising the same data. These approaches are the traditional regression model (TRM) with only one level of heterogeneity approach and the hierarchical regression model (HRM) with many levels of heterogeneities approach. A Metro North Western (MNW) urban road network in Victoria (Australia) was considered as the case study for this study investigation where covering the condition of approximately 305 Km of asphalt surfaced pavements. By considering the structure of time series data, the study revealed that more accurate models could predict the pavement behaviour, the deterioration rate, and significantly influenced parameters. In addition, the study highlighted that it is essential to deliberate and process the hierarchical structure of datasets to consider the observed and unobserved heterogeneities in time series data for developing any pavement performance model using either deterministic or probabilistic prediction approaches. Multiple simulation scenarios have been performed for both approaches and the HRM approach shows more reasonable outputs. For predicted deterministic SIR models, road intervention (SIR ≥ 20) are triggered at age 12.5 when using TRM approach and at age 10.5 when using HRM approach. For predicted probabilistic SIR models, the surface condition of a section with SIR weighted average condition values of 2 is triggered at age 17.5 when using TRM approach and at age 10.5 when using HRM approach. This also refers to earlier maintenance scheduling is required when using the later approach because it deals confidentially with each road sections time series data. In that regard, ignoring the uncertainty in time series data of such factors in the road surfacing maintenance scheduling problems may lead to suboptimal solutions and unstable pavement conditions. [ABSTRACT FROM AUTHOR]

Designing perfect anomalous reflectors is crucial for achieving many metasurface-based applications, but available design approaches for the cases of extremely large bending angles either require unrealistic gain–loss materials or rely on brute-force optimizations lacking physical guidance. Here, we propose a deterministic approach to design passive metasurfaces that can reflect impinging light to arbitrary nonspecular directions with almost 100% efficiencies. With both incident and out-going far-field waves given, we can retrieve the surface-impedance profile of the target metadevice by matching boundary conditions with all allowed near-field modes added self-consistently and then construct the metadevices deterministically based on passive meta-atoms exhibiting local responses. We design/fabricate two proof-of-concept microwave metadevices and experimentally demonstrate that the first one achieves anomalous reflection to a 70° angle with efficiency ∼98%, and the second one can generate multiple reflected beams with desired bending angles and power allocations. Our findings pave the way for realizing high-efficiency wave-control metadevices with desired functionalities.

In this study, breeding objective traits were identified, and alternative breeding schemes were simulated and evaluated for two goat populations. The traits were as follows: body size, twinning ability and kidding interval (KI) for Arab goats and body size, twinning ability and mothering ability for Oromo goats. The selection criteria were six-month weight (6mw, kg), litter size at birth (LSB), litter size at weaning (LSW) and KI (days). The schemes were as follows: (1) Scheme 1: 2 years of buck use and 10% selection proportion, (2) Scheme 2: 2 years of buck use and 15% selection proportion, (3) Scheme 3: 3 years of buck use and 10% selection proportion, and (4) Scheme 4: 3 years of buck use and 15% selection proportion. The predicted annual genetic gain (PAGG) for 6mw ranged from 0.29 to 0.32 kg for Arab goats while it varied from 0.34 to 0.38 kg for Oromo goats. On the contrary, the PAGGs for LSB and LSW for both populations were considerably small regardless of the different schemes. The economic return (Euro/doe) ranged from 0.99 to 1.15 for Arab goats and from 0.60 to 0.70 for Oromo goats. SCM2 is recommended over other schemes.

In this paper, we are interested in the numerical aspects of the class of generalized Riccati difference equations which are involved in linear quadratic (LQ) stochastic difference games. More specifically, we address the problem of the numerical computation of the stabilizing solutions for this class of nonlinear difference equations. We propose an iterative deterministic algorithm for the computation of such a global solution. The performances of the proposed algorithm are illustrated with some numerical examples. [ABSTRACT FROM AUTHOR]

Despite being convenient and practical, current nanomedicine (NM) release kinetic models remain unscalable, non-specific and less descriptive of the underlying physicochemical determinants. However, a deterministic mathematical modelling could overcome these limitations. In this study, we develop a model, based on a system of two differential equations (accounting for nanoparticle (NP) degradation and then drug release from degraded NM), which enable us to estimate per capita rate constant α (#NP degraded/hr) and β (Drug Amount Released/NP), the net effect of the nanomedicine (NE factor ɣ= α.β) and the controlled release index (φ, ratio of drug release to NP degradation). The model analysis conducted with tenofovir loaded hyaluronidase sensitive NM clearly shows the α factor significantly increased with triggering stimuli due to its enzymatic action on its substrate (hyaluronic acid). However, the β factor remained relatively unchanged, due to intrinsic physicochemical properties of the drug as limiting factor. The application of the solutions of this model clearly enabled us to effectively screen among various nanoformulations and identified the best hyaluronidase-sensitive NM formulation, exhibiting the highest ratio (3.7-fold increase compared to no enzyme). The φ value confirmed the controlled release and stimuli sensitivity of the nanosystem. Moreover, the computed drug release rate (dM/dt) is consistent with other existing mathematical models (under valid assumption). The key advantages of this approach are i) relevancy to underlying physicochemical and biochemical process, ii) versatility and application to various NM kinetics, and iii) prediction of temporo-spatial distribution of the drug loaded NP that could potentially improve in-vitro/in vivo correlation study. This unique approach is applicable for a more specific and more meaningful/physicochemically relevant description of bioactive agents release from NM or NP for various applications.

Liquefaction-induced damage has been observed in several moderate to large earthquakes. Intensive efforts have been made to understand the liquefaction mechanism and develop procedures for analyzing the liquefaction potential at a particular site. In the present study, we aimed to evaluate liquefaction potential of Kolkata City, located between latitudes 22°20′ N–23°00′ N and longitudes 88°04′ E–88°33′ E, based on Standard Penetration Test (SPT) N values. The deterministic approaches as per Idriss and Boulanger [Soil liquefaction during earthquakes, Monograph (MNO)-12, Earthquake Engineering Research Institute, 2008] and IS 1893: Part 1 (Criteria for earthquake resistant design of structures—part 1: General provisions and buildings, Bureau of Indian Standards, 1893) have been used to determine the liquefaction potential of the city. The detailed soil data from 500 boreholes located across 75 locations of the city are analyzed at various depths below the ground surface for varying earthquake moment magnitudes (Mw) of 6.5, 7, 7.5 and 8 at peak horizontal ground surface acceleration (amax) of 0.24 g. The evaluation is carried out in terms of factor of safety against liquefaction (FSL). Hazard zonation maps and contour maps are also developed in the present study using ArcGIS 10.5 (ArcGIS Desktop Release 10. Environmental Systems Research Institute, California, 2016). It is observed that with the increase in depth, liquefaction potential decreases but increases with the increase in the magnitude of the earthquake. Conclusively, the two approaches yielded different factor of safety (FSL) values for the same soil data with the IS 1893: Part 1 (IS: Part 1, Criteria for earthquake resistant design of structures—part 1: General provisions and buildings, Bureau of Indian Standards, 1893) method giving higher values of FSL compared to the Idriss and Boulanger [Soil liquefaction during earthquakes, Monograph (MNO)-12, Earthquake Engineering Research Institute, 2008] method, indicating less risk of liquefaction. [ABSTRACT FROM AUTHOR]

This paper introduces an innovative numerical scheme that may accurately quantify the parameter and response distributions with minimal computational costs, with specific applications to the numerical computation of multiphase flows under various fluid conditions. The probabilistic approach of uncertainty quantification, e.g., the Monte Carlo simulation, although known to be effective in estimating the parameter/response distribution for highly nonlinear problems, is usually not applicable to multi-physics and multi-scale integrated systems due to its high computational cost. The objective of this study is first, to reduce the computing demand for complex physical system calculations and, at the same time, to accurately predict actual probability distributions by developing a higher order deterministic approach to uncertainty quantification. To achieve this, instead of executing simulation codes multiple times to estimate the probability distribution, the first to fourth moments of the probability density function are derived directly by employing a second order Taylor expansion form of the responses along with Bayesian statistics. This characterizes the parameter and response distributions computed by inverse and forward uncertainty quantification based on their mean value, mode, covariance, skewness, and kurtosis. The parameter distribution is estimated by the numerically calculated higher moments of the parameters with a posteriori probability density function being derived by Bayesian inference. The parameter distribution is then mapped into the second order approximated response function to compute the characteristics of the response distribution through both analytical calculation and numerical approximation of the moments of the responses. The proposed approach is numerically demonstrated through simulations of two benchmark problems: MIT pressurizer and FEBA tests. The prediction of the responses is improved by inverse uncertainty quantification as numerical calculations with the a posteriori model parameters are in better agreement with the measured data over a wide range of transient periods. Additionally, the response distribution estimated by the proposed approach of forward uncertainty quantification accurately predicts the distribution computed by the Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

In this study, breeding objective traits were identified, and alternative breeding schemes were simulated and evaluated for two goat populations. The traits were as follows: body size, twinning ability and kidding interval (KI) for Arab goats and body size, twinning ability and mothering ability for Oromo goats. The selection criteria were six-month weight (6mw, kg), litter size at birth (LSB), litter size at weaning (LSW) and KI (days). The schemes were as follows: (1) Scheme 1: 2 years of buck use and 10% selection proportion, (2) Scheme 2: 2 years of buck use and 15% selection proportion, (3) Scheme 3: 3 years of buck use and 10% selection proportion, and (4) Scheme 4: 3 years of buck use and 15% selection proportion. The predicted annual genetic gain (PAGG) for 6mw ranged from 0.29 to 0.32 kg for Arab goats while it varied from 0.34 to 0.38 kg for Oromo goats. On the contrary, the PAGGs for LSB and LSW for both populations were considerably small regardless of the different schemes. The economic return (Euro/doe) ranged from 0.99 to 1.15 for Arab goats and from 0.60 to 0.70 for Oromo goats. SCM2 is recommended over other schemes. [ABSTRACT FROM AUTHOR]

Indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) is an ideal immunoassay method for large-scale screenings to detect mycotoxin contaminants. However, the matrix effect of complicated samples has always been challenging when performing immunoassays, as it leads to false-positive or negative results. In this study, convenient QuEChERS technology combined with optimizing the dilution solvent was ingeniously used to eliminate interference from the sample matrix to greatly improve the detection accuracy, and reliable ic-ELISAs for the two official tolerance levels of 60 and 500 μg/kg were developed to screen zearalenone (ZEN) in edible and medical coix seeds without any further correction. Then, the 122 batches of coix seeds were determined, and the positive rate was up to 97.54%. The contaminated distribution was further analyzed, and risk assessment was subsequently performed for its edible and medical purposes. The findings indicated that consumption of coix seeds with higher ZEN contamination levels may cause adverse health effects for both medical and edible consumption in the adult population; even under the condition of average contamination level, ZEN from coix seeds was the more prominent contributor to the total risk compared to other sources when used as food; thus, effective prevention and control should be an essential topic in the future. [ABSTRACT FROM AUTHOR]

Heat Exchanger Network (HEN) synthesis is primarily formulated as a mixed integer non-linear programming (MINLP) problem based on method of stage-wise superstructure (SWS). Approaches to obtain an optimal HEN configuration can adopt deterministic algorithms. But, as a large scale problem, it is difficult to solve due to the complexities arisen from nonlinearities of SWS. To overcome the model nonlinearities, stochastic algorithms and meta-heuristic approaches have been proposed in the literature to tackle the problem. However, it reaches a near-optimal HEN configuration from a series of stochastic solutions, which are obtained by the execution of many computational procedures with extensive time resource, and a global optimum will not be guaranteed from only randomly generated results. In this paper, an enhanced SWS approach is proposed, in which new temperature and heat duty constraints are updated to reduce the redundant combinations and avoid conflicted calculation of non-isothermal mixing energy balance. The present model is also extended to allow flexible stream splitting for practical applications. Then, a deterministic-based global solver (GAMS/BARON) is applied in solving three case studies. The results show that the proposed approach can provide cost-efficient HEN solutions with lower TAC than using existing stochastic and deterministic algorithms.

In this paper, we are interested in the numerical aspects of the class of generalized Riccati difference equations which are involved in linear quadratic (LQ) stochastic difference games. More specifically, we address the problem of the numerical computation of the stabilizing solutions for this class of nonlinear difference equations. We propose an iterative deterministic algorithm for the computation of such a global solution. The performances of the proposed algorithm are illustrated with some numerical examples.

Aluminium outfitting is widely used in offshore platforms owing to its anti-corrosion ability and its light weight. However, various standards exist (ISO, NORSOK and EN) for the design of handrails used in offshore platforms, and different suppliers have different criteria. This causes great confusion for designers. Moreover, the design load required by the standards is not clearly defined or is uncertain. Thus, many offshore projects reference previous project details or are conservatively designed without additional clarification. In this study, all of the codes and standards were reviewed and analysed through prior studies, and data on variable factors that directly and indirectly affect the handrails applied to offshore platforms were analysed. A total of 50 handrail design load scenarios were proposed through deterministic and probabilistic approaches. To verify the proposed new handrail design load selection scenario, structural analysis was performed using SACS (offshore structural analysis software). This new proposal through deterministic and probabilistic approaches is expected to improve safety by clarifying the purpose of the handrails. Furthermore, the acceptance criteria for probabilistic scenarios for handrails suggest considering the frequency of handrail use and the design life of offshore platforms to prevent excessive design. This study is expected to prevent trial and error in handrail design while maintaining overall worker safety by applying a loading scenario suitable for the project environment to enable optimal handrail design.

Rock slope projects are often available with insufficient investigation data for rock properties due to involvement of high costs, manual efforts, geological complexities, etc., in testing. Support estimation performed by traditional approaches for slope failure mitigation could be highly inaccurate due to inaccuracies in the estimated statistics of properties. This article describes a computationally efficient re-sampling stochastic framework to overcome this issue by coupling the Advanced Re-Sampling Reliability Approach (ARRA) with deterministic and Target Reliability Approach (TRA) to estimate the required support for rock-slides mitigation with limited data. The proposed methodology was demonstrated for the support design to mitigate two massive rockslides along a rockslide-prone highway, i.e., Rishikesh-Badrinath National Highway (NH-58) in India. It was concluded that the limited data invokes uncertainties in the statistical parameters (mean and standard deviation) and distributions of properties. Support estimated using traditional approaches with the inaccurate statistics of input properties can result in inaccurate support estimates in the presence of insufficient data. Proposed methodology couples ARRA with traditional methods and evaluates the final support design by quantifying the uncertainty in the reliability index induced by the statistical uncertainties of input properties statistics. This improves the overall accuracy, efficiency, and the designer's confidence in the estimated support. [ABSTRACT FROM AUTHOR]

Deterministic approaches have recently been developed for accurate computation in stochastic computing (SC). They, however, suffer a long operation time. Fortunately, for applications that do not require completely accurate processing results, such as image processing, the time can significantly be reduced due to the better progressive precision in the bit-streams generated by these approaches. That means a computation can be terminated in time when its output accuracy is acceptable. Due to the fast convergence property of low-discrepancy sequences, we propose three deterministic Halton sequence (DHS)-based stochastic number generators (SNGs) for the first time by using, respectively, prime length, rotation, and clock division for accelerating computation in SC. Experimental results show that the proposed designs are more efficient than their counterparts. For multiplication, the proposed DHS-based designs perform up to $32\times $ faster than prior designs for a mean error of 0.1%. The speedup reaches $128\times $ for an edge detection algorithm. Three stochastic circuits are then designed by using the proposed DHS-based SNGs for the Bernsen binarization algorithm, which lead to more accurate results than existing designs at the same bit-stream length. Finally, the proposed designs show an excellent fault-tolerance against bit flipping errors. [ABSTRACT FROM AUTHOR]

As all countries around the world, Saudi Arabia has been affected by the spread of covid-19 that started in a Chinese city by the end of December 2019. The impact of spread can be evaluated in different levels, loss of life as the country has already recorded more than 7500 deaths, the impacts on Saudi economy, schooling systems and many others sectors that have been impacted. The main aim of this work is to provide a statistical and deterministic analysis on the spread of covid-19 within the Kingdom of Saudi Arabia. Statistical investigation on collected data were performed, including fitting of data using some statistical distributions, seven days moving average for deaths, recovered and infected. Additionally, a simple SIR mathematical model based on the concept of piecewise modeling, where the model is defined within interval with the aim to capture the crossover displaying by the spread within the kingdom of Saudi Arabia.

The study is aimed to investigate earthquake hazard zoning in Boroujerd with emphasis on urban development based on Deh Cheshmeh earthquake. The study area is located in the Zagros and Sanandaj zones in Sirjan tectonically and has a relatively high seismic activity. To study seismicity and seismic hazard analysis within a range of 200 km, the deterministic and probabilistic methods and Zare's updated reduction relationship and Norouzi relationship have been used. In this study, raw catalogs from reputable databases such as ISC and USGS were used, and Gardner and Knopoff (1974) methods were used to eliminate dependent earthquakes. Seismic parameters were completed through using the method provided by Kiko and were the basis for analysis. The results showed that the maximum horizontal accelerations obtained in the deterministic approach were 0.23, 0.18, and 0.17 g, respectively, which were related to the High Zagros Fault (H.Z.F), Nahavand fault, and Doroud fault, respectively. Also, the maximum vertical accelerations obtained in the deterministic approach were 0.11, 0.09, and 0.08 g, respectively, which were related to the High Zagros (H.Z.F), Nahavand fault, and Doroud fault, respectively. Also, in the probabilistic approach and at the DBE design level, the maximum horizontal and vertical accelerations were 0.30 and 0.14 g, respectively, and at the OBE design level, the above components were 0.22 and 0.10 g, respectively. By using the results of this research that is gained through the possible method of maximum horizontal acceleration 0.3 and in deterministic method 0.23g, 0.13 and 0.34 decrease can be seen in base shear. [ABSTRACT FROM AUTHOR]

The Bayesian inversion method is a stochastic approach based on the Bayesian theory. With the development of sampling algorithms and computer technologies, the Bayesian inversion method has been widely used in geophysical inversion problems. In this study, we conduct inversion experiments using crosshole seismic travel-time data to examine the characteristics and performance of the stochastic Bayesian inversion based on the Markov chain Monte Carlo sampling scheme and the traditional deterministic inversion with Tikhonov regularization. Velocity structures with two different spatial variations are considered, one with a chessboard pattern and the other with an interface mimicking the Mohorovičić discontinuity (Moho). Inversions are carried out with different scenarios of model discretization and source–receiver configurations. Results show that the Bayesian method yields more robust single-model estimations than the deterministic method, with smaller model errors. In addition, the Bayesian method provides the posterior probabilistic distribution function of the model space, which can help us evaluate the quality of the inversion result.

Indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) is an ideal immunoassay method for large-scale screenings to detect mycotoxin contaminants. However, the matrix effect of complicated samples has always been challenging when performing immunoassays, as it leads to false-positive or negative results. In this study, convenient QuEChERS technology combined with optimizing the dilution solvent was ingeniously used to eliminate interference from the sample matrix to greatly improve the detection accuracy, and reliable ic-ELISAs for the two official tolerance levels of 60 and 500 μg/kg were developed to screen zearalenone (ZEN) in edible and medical coix seeds without any further correction. Then, the 122 batches of coix seeds were determined, and the positive rate was up to 97.54%. The contaminated distribution was further analyzed, and risk assessment was subsequently performed for its edible and medical purposes. The findings indicated that consumption of coix seeds with higher ZEN contamination levels may cause adverse health effects for both medical and edible consumption in the adult population; even under the condition of average contamination level, ZEN from coix seeds was the more prominent contributor to the total risk compared to other sources when used as food; thus, effective prevention and control should be an essential topic in the future.

The Iranian Plateau has been subjected to destructive earthquakes throughout its history. Reliable assessment of the seismic hazard in this earthquake-prone region is therefore essential. Our study focuses on estimating the maximum earthquake magnitude as one of the main parameters of seismic hazard analysis. We implemented two quantitative approaches, namely, probabilistic and deterministic. The probabilistic method allows combining the historical (i.e. incomplete) and the instrumental parts of a catalogue with different levels of completeness and considers the uncertainties in earthquake magnitude determination. In this study, we used a unified, declustered, and complete catalogue of earthquakes in Iran, covering the period from the fourth century BC to 2019. We calculated the maximum possible magnitudes for hundreds of grid points by using the seismicity data in a 200-km radial region around each grid point. The maximum possible earthquake was observed to vary between 6.0 and 8.2, and the highest values were found in the Alborz-Azarbayejan seismotectonic province, Kopeh-Dagh, central east Iran, Makran, and the southeast Zagros. The lowest mmax values were found in the Persian Gulf, Arabian Platform, Esfahan-Sirjan region, and the Dasht-e-Kavir Desert in central Iran. As a second part to this study, we calculated the maximum credible earthquakes for 1103 identified major faults by using five empirical magnitude-scaling relationships. Our results were consistent with both the observed earthquakes and the seismic potential of the various seismogenic zones of Iran. The study results can be used in future seismic hazard analyses and have fundamental implications for mitigating seismic risk in Iran. [ABSTRACT FROM AUTHOR]

Adding noise to a system can 'improve' its dynamic behaviour, for example, it can increase its response or signal-to-noise ratio. The corresponding phenomenon, called stochastic resonance, has found numerous applications in physics, neuroscience, biology, medicine and mechanics. Replacing stochastic excitations with high-frequency ones was shown to be a viable approach to analysing several linear and nonlinear dynamic systems. For these systems, the influence of the stochastic and high-frequency excitations appears to be qualitatively similar. The present paper concerns the discussion of the applicability of this 'deterministic' approach to stochastic systems. First, the conventional nonlinear bi-stable system is briefly revisited. Then dynamical systems with multiplicative noise are considered and the validity of replacing stochastic excitations with deterministic ones for such systems is discussed. Finally, we study oscillatory systems with nonlinear damping and analyse the effects of stochastic and deterministic excitations on such systems. This article is part of the theme issue 'Vibrational and stochastic resonance in driven nonlinear systems (part 1)'. [ABSTRACT FROM AUTHOR]

The article studies the technique of synthesis of random sequence filters with unknown prior statistical information about the parameters of signal and noises. The synthesis uses only current measurements and a limited amount of empirical information, which leads to the necessity of using a deterministic approach based on the least squares method. In order to obtain a recursive filtering algorithm, it is proposed to extend the structure of the method loss function by including in loss function an additional term that defines the estimate extrapolation for the next measurement period. The optimal current estimate is based on both measurement results and extrapolated values. The extrapolation function is selected based on the desired class of synthesized filter. The paper considers a variant of polynomial extrapolation, taking into account previous estimates and measurements. The use of only previous estimates leads to the structure of the filter with feedback, while the use of only the previous measurements forms a transversal filter. Mathematical modeling was carried out and on particular example and the loss of filtering accuracy by not taking into account a priori statistical information was estimated.

Frequency synchronization in single-carrier frequency division multiple access (SC-FDMA) uplink system is a challenging task due to the presence of different carrier frequency offsets (CFOs) for different users. In this paper, we propose a blind CFOs estimation algorithm for SC-FDMA uplink system by oversampling method in the presence of frequency selective fading channel. A cost function is derived which minimizes the power of the off-diagonal elements of a signal covariance matrix while estimating the correct CFOs. The off-diagonal elements are nothing but inter-carrier interference and multiple-access interference introduced in the presence of multiple CFOs. A complete mathematical model has been presented for multiple CFOs estimation under multiple access scenarios. The proposed CFOs estimation method does not require channel-state information which results in lower computational complexity. The higher iteration complexity of grid search algorithm has been further reduced by a deterministic approach. We also derive the Cramer-Rao bound for CFO estimation. The simulation results show that the proposed CFOs estimation method outperforms the existing subspace theory-based methods, specifically in the low signal-to-noise ratio region.

When single-phase three-level neutral-point-clamped (NPC) converters operate, there are two main control objectives that need to be met for correct operation. First, the ac source current must be controlled to be sinusoidal. Second, the dc capacitor voltages must be balanced. In original model predictive control (MPC) methods for NPC converters, an optimization process involving an empirical weighting factor design is required to meet both of these objectives simultaneously. This study proposes an MPC approach developed for single-phase three-level NPC converters to meet these objectives using a single reference voltage consisting of a difference-mode term and a common-mode term in each phase. The difference-mode term and the common-mode term are responsible for sinusoidal ac source current synthesis and dc capacitor voltage balancing, respectively. Then, a single cost function compares the adjusted reference voltage with possible voltage candidates to select an optimal switching state, resulting in the smallest cost function value. Different from the conventional MPC method, the proposed approach avoids the selection of weighting factors and the attendance of various control objectives. Thanks to the deterministic approach, the proposed MPC method is straightforward to implement and maintain fast transient performance while guaranteeing the control objectives. Finally, the effectiveness and feasibility of the proposed approach for single-phase three-level NPC are verified through comprehensive experimental results. [ABSTRACT FROM AUTHOR]

The Iranian plateau is located in the high seismicity belt. Earthquake can inflict severe loss of life and property, especially when they occur in densely populated areas. Therefore, seismic hazard evaluation is very essential to prevent the harmful effects. The region of the study is located in the northwest of Iran, between 43°-50° E longitude and 35.5°-40.5° N latitude. This city which is located in the center of East Azerbaijan province, has been ruined by terrible earthquakes, which is due to the presence of active faults in the region. Seismic hazard assessment similar to other seismology researches is very complicated due to the effect of different parameters in an earthquake occurring with uncertainty. The amount of uncertainty should be considered in a rational way. The fuzzy method is a suitable method that is used as a decision-making method for solving problems and modeling uncertainties and ambiguities. We used a fuzzy inference system, as the practice is based on uncertainty estimation of seismic hazard for Tabriz region. Peak ground Acceleration value is estimated for fuzzy Logic System in deterministic method 0.55g which is obtained from a seismic source with a Mmax=8.0 at a distance of 36.98 km of Tabriz city. The contour map of the peak ground acceleration throughout Tabriz city can help in urban planning. [ABSTRACT FROM AUTHOR]

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During the service life of the orthotropic steel bridges (OSBs), fatigue damage accumulations could impact the safety and reliability of the bridges in their lifecycles. Fatigue damage evaluations of bridge weldments for the OSBs have been performed by many researchers for different loading scenarios and environmental conditions. During an extreme flooding event after many years of scour effects on bridge foundation, the foundation might fail and trigger the failure of the entire bridge. Many researchers have evaluated the effects of scour on the modal frequencies to monitor the depth of the foundation scour. For different dynamic characteristics of the bridges considering different soil and foundation conditions, it is not clear how the local stresses at the weld joints might be affected. In the present study, fatigue damage assessments of the bridge weld joints for the OSBs are conducted with the consideration of foundation scour of the bridges. First, a short span OSB is modeled in multiple length scales to balance computational costs and accuracy. The bridge welds are simulated in detail to capture the possible dynamic effects at these local structural details under different vehicle loadings. Soil springs are applied for the pile foundation, and the scour is simulated by releasing the soil springs. Using the hotspot stress method and the effective notch stress method, the revised equivalent stress ranges at the toe-deck crack, deck panel crack, floor beam crack, trough web crack, and root-deck crack are calculated. Based on the accumulated fatigue damages, reliability assessments of these cracks at different scenarios are performed. The fatigue life of the OSB is controlled by the cracks initiated at the floor beam-to-deck joints and the floor beam-to-rib joints. Considering foundation scour, the fatigue life of the weld joints is reduced by 22% at the maximum. The deterministic approach proposed in the specification is also used to predict the fatigue life of the weld joints. By introducing the effects of foundation scour, the fatigue life of the OSBs can be estimated more accurately. [ABSTRACT FROM AUTHOR]

This study presents a probabilistic approach to calculate locational marginal price (LMP) at distributed generation (DG) buses in an electric power distribution system to ensure that the network operates at reduced active power losses (APLs). The proportional nucleolus theory‐based iterative method is proposed as a deterministic approach to compute LMP based on APLs. Uncertainties in load and market price were captured by using a 2m+1 scheme of the point estimation method. To compute the contribution of the reactive and active power of the DG on the APL of the network, loss sensitivity factors have been developed. The proposed method provides an active power price in terms of LMP and reactive power price to each DG as per its contribution to loss reduction. To verify the performance of the proposed method, it was implemented on the Taiwan Power Company distribution system. The proposed method can be utilised by a distribution company to operate the network at reduced APL and improve the benefit of DG owners. [ABSTRACT FROM AUTHOR]

[Display omitted] • The use of probabilistic approach enhances safety and accuracy in flood studies. • Deterministic approach even with a climate factor underestimates flood magnitude. • The principal source of uncertainty is precipitation that involves RCP, PDF and CM. • PDF is the main source of precipitation uncertainty, while RCP has the least impact. This study presents an assessment of the uncertainty associated with 100-year flood maps under three scenarios: present, RCP4.5, and RCP8.5. Through intensive Monte Carlo simulations, the study focuses on evaluating the uncertainty introduced by key model input parameter, namely the roughness coefficient, runoff coefficient, and precipitation intensity. Notably, the precipitation intensity incorporates multiple sources of uncertainty, including RCP scenario, climate model, and probability distribution function. To analyze the uncertainties, a surrogate hydrodynamic/hydrologic model based on a physical 2D model is employed. The findings of this study challenge the traditional use of deterministic flood maps and climate factors, highlighting the necessity of employing probabilistic approaches for the development of accurate and secure flood maps. Moreover, the research findings indicate that the primary source of uncertainty in precipitation is the selection of the probability distribution, followed by the choice of climate model, and to a lesser extent, the specific RCP scenario. [ABSTRACT FROM AUTHOR]

Seismic design of an embankment dam is a vital step in the design procedure of this important infrastructure. Deterministic approaches such as quasi-static and Newmark method have been employed to evaluate slope stability of embankment dams. However, the variables required for a slope stability analysis, e.g. soil strength, pore pressure and loading parameters involve uncertainties which cannot be handled in the traditional deterministic methods. As an alternative, reliability analysis might be conducted to assess reliability indexes and the related failure probability of embankment dams. In this study, based on probability theories, a reliability analysis is performed to evaluate the seismic stability of an embankment dam (i.e., Gotvand dam) constructed in Iran. The probability of failure under seismic loading is considered for different sources of uncertainties involved in the problem, including uncertainty of loading, and the friction angle of core material as a strength parameter. Employing some statistical parameters, dynamic analysis is performed to determine the influence of friction angle variation on seismic slope stability. Significant pore pressure may build-up during cyclic loading, especially, when mixed clay (mixed clay and gravel) constitutes the dam core. Also, an undrained behavior of core materials has a great importance. Therefore, to estimate the effect of pore pressure build-up during seismic loading, two types of core materials (pure clay and mixed clay) are considered in this research. The results of dynamic analysis by finite element method are used to obtain the critical surface and acceleration in the embankment. Then, Newmark approach is employed to calculate the permanent displacement of the dam. Finally, reliability analysis is conducted and seismic performance of Gotvand dam during the earthquakes is investigated. [ABSTRACT FROM AUTHOR]