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Highlights • First results of Canadian Nuclear Laboratories' new PT-HWR transient simulation toolset. • SALOME-based coupling of ARIANT (formerly known as CATHENA4) and NESTLE-C. • Results for a stylized 20% LBLOCA are presented. Abstract Canadian Nuclear Laboratories has developed a toolset of coupled reactor transient simulation codes for pressure tube heavy water reactors. This paper presents the first demonstration of the toolset's capabilities, using a hypothetical 20% reactor inlet header break (critical break) scenario. This scenario induces strong feedback between thermalhydraulic and reactor physics phenomena, owing to a positive coolant voiding coefficient. The scenario was simulated using the advanced thermalhydraulics code ARIANT and the reactor physics code NESTLE-C, coupled together using the SALOME platform. This paper summarizes recent advances in ARIANT, the coupling methodology, and the results of the transient simulation. [ABSTRACT FROM AUTHOR]

Highlights • Fault leads to reduction in motor's efficiency which increases its energy consumption and CO 2 emission. • As the fault propagates, these losses increase further and are generally ignored by the industries. • Efficiency monitoring based CBM has been proposed as a part of motor maintenance strategy. • Proposed strategy considers the faulty motor running loss for planning maintenance action. Abstract Induction motors are the major source of energy consumption in industries. Research work available on motor efficiency and energy consumption advocates the use of energy efficient motors to reduce the power consumption. However, these motors are also prone to faults which affects their operational efficiency. Over a period of time, the propagation of fault in the motor leads to the further drop in the efficiency which increases motor running loss. This loss is generally ignored by most of the researchers and managers and is a hidden cost borne by the industries. In this paper running of faulty induction motors and its associated financial losses have been addressed. It has been assumed that for a motor running at constant load, fault propagation leads to further drop in its efficiency. Three simulated scenarios: linear, exponential and quadratic drop in efficiency have been considered for estimation of running loss. An algorithm has also been proposed for planning maintenance actions based on operational losses due to faulty motor. This paper also highlights how efficiency and condition monitoring helps in reducing CO 2 emission. [ABSTRACT FROM AUTHOR]

Highlights • A parameterized SILs verification approach is proposed on baseline of IEC61508. • Fully correctness proving is done by implementing and comparing with IEC61508-6. • Parametric features facilitate model reuse in large-scale, complex systems. • PFH relies on the balance between CCF and the number of the redundancy channels. • Systems with static components can be simulated by this approach. Abstract The paper proposed an approach of verifying the Safety Integrity Level (SIL) for the high demand safety system. This approach is based on the Stochastic Petri Nets models and Monte Carlo simulation (SPN-MC) and follows the requirements of IEC61508, which is a commonly accepted standard in the domain of functional safety of programmable electronic and control engineering systems. The paper provides a comparative analysis of the SIL with the application of SPN-MC and the Reliability Block Diagram (RBD) method given by EN61508 to prove the correctness and feasibility of the SPN-MC approach. Additionally, a typical large scaled complex system was adopted to apply the novel approach, which is hard for classical analytical methods. [ABSTRACT FROM AUTHOR]

Highlights • Visual simulation of wind farms should include at least 30° variation in blade orientation. • Impact analysis can incorporate visibility data, and its effect on color contrast, through the extinction coefficient. • Use of the worst-case scenario in simulation and analysis can be moderated. Abstract The visual impact of wind turbines is a central issue in their public acceptance. New wind farm proposals are commonly subject to visual simulation and visual impact assessment. Guidelines for both these processes are already used in a number of jurisdictions and there is widespread interest in making simulation and impact assessments as meaningful as possible. To a large degree the guidelines for both processes tend to be based on worst-case (full-frontal) conditions. There are two quite good reasons for this. Firstly, the worst-case sets a boundary for visual impact. Secondly, we seldom know enough about how visibility or visual impact changes over time and what 'typical' conditions are like – or how the range of conditions is distributed. This paper argues that if we can address this knowledge gap, then we may also be able to take a more nuanced approach to simulation and analysis. It should be possible, using widespread atmospheric visibility data, to determine the temporal distribution of visual impacts at a particular location rather computing a single estimate. It may also be valid to create simulations of both worst-case and more typical conditions. This paper explores the key variables affecting visual impacts – visual magnitude and color difference – and how they may be monitored and analyzed efficiently and effectively. A wind farm in southern Victoria, Australia is used as the case study. Recommendations are made on how the approaches could be used more widely. [ABSTRACT FROM AUTHOR]

Abstract Terrestrial laser scanning is extensively adopted in the area of high-precision monitoring and three-dimensional measurement. Architectural structures today are increasingly complex and health monitoring plays an important role in guaranteeing their safety. Therefore, how reliability deformation monitoring can be improved is one of the key problems in the field of engineering. This paper combines the three-dimensional laser scanning technology and finite element method (FEM) to investigate the deformation mechanism of arched structures. Within this paper, we simulated arched structures using the FEM, which is consistent with the result of terrestrial laser scanner (TLS) measurement. We aimed at constructing an intelligent and efficient FEM model which can be extensively applied in the monitoring of many constructs, such as bridges and ancient architecture. The focus in this research lies mainly on deformation analysis, which is based on FEM model simulation with the calibration of TLS measurement. [ABSTRACT FROM AUTHOR]

A Physical Internet of hubs ('PI-hubs') is a network of logistics terminals that allow shipments to flow through, similar to the flow of Internet data packets. PI-hub networks are a recent proposal and their properties have not been studied in detail. In this paper we model PI-hub networks using the theory of queuing networks, particularly, Jackson queuing networks. Under certain assumptions, PI-hub networks behave like Jackson queuing networks, and thus analytical methods can be used to calculate important properties such as throughputs, processing times, traffic size etc. In this paper we analyse the performance characteristics (throughput, queue size) for each PI-hub and for the whole PI-hub network. [ABSTRACT FROM AUTHOR]

Highlights • This paper proposes equivalent models of active distribution networks (ADN). • Equivalent models allow TSOs to expand the system observability. • The proposed model is able to take into account the prior knowledge of an ADN. • The model can be easily adapted to different configurations of the ADN. • The approach is validated by a simulation study on a Benchmark MV Active Network. Abstract This paper proposes a methodology for the identification of equivalent models of active distribution networks. Due to the increasing installation of distributed generation plants, distribution networks are acquiring an "active" role in the management of the overall power system. In this context, equivalent modeling is becoming essential for allowing transmission system operators to expand the system observability and improve the interoperability with distribution system operators. The present paper proposes a nonlinear model and an identification procedure able to take into account the prior knowledge of a given active distribution network. The result is an equivalent model, which can be easily adapted for reproducing the dynamical behavior of the network with different configurations. The proposed approach is validated through a simulation study on a Benchmark Medium Voltage Active Network. [ABSTRACT FROM AUTHOR]

Highlights • Variable renewable energy integration diminishes synchronous inertia of power systems, resulting in vulnerable frequency instability. • Alternative options of fast frequency resources are required for secure and stable grid operation under high penetration of renewables. • This paper provides a critical review of potential sources of fast frequency reserves, and way forward to maintain secure and stable grid operation. Abstract The last few decades have seen renewable energy source (RES) integration growing at a rapid pace and this trend is likely to continue. The displacement of conventional synchronous plant, particularly at higher RES shares, is resulting in a 'lighter' system with low system inertia and reduced governor droop stiffness, leading to increased vulnerability to fast frequency stability. This paper presents a review of literature from the research and industry communities on possible sources of non-synchronous fast frequency reserve, considered as a potential solution to address diminishing synchronous reserve in RES integrated systems. The wide range of potential sources includes wind turbines, solar photovoltaic plant, energy storage, high voltage direct current (HVDC) systems, and demand response. The challenges and limitations associated with each approach are highlighted, and alternative strategies to maintain a minimum volume of security constrained fast frequency reserve are discussed based on the recent industry trends. [ABSTRACT FROM AUTHOR]

Highlights • Self-driving vehicles are conservative toward pedestrian traffic, negotiation is a solution to this problem. • A vehicle–pedestrian negotiation framework for interaction among multiple vehicles and pedestrians is proposed in this paper. • Negotiation model considers different risk-taking behaviors of pedestrians and demonstrates negotiation by self-driving vehicle with a mixed population of such pedestrians. • Simulation results show improved waiting times of vehicles and the overall throughput at intersections compared to the conservative behavior of self-driving vehicles. Abstract Negotiations among drivers and pedestrians are common on roads, but it is still challenging for a self-driving vehicle to negotiate for its right of way with other human road users, especially pedestrians. Currently, the self-driving vehicles are programmed for conservative behavior, yielding to approaching pedestrians. Consequently, the future urban traffic will slow down significantly. In this paper, a conceptual model of vehicle–pedestrian negotiation is proposed. This model allows individual decision making of multiple vehicles and pedestrians, extending a prior negotiation model for a single vehicle and a single pedestrian. The possible negotiation opportunities for vehicles are modeled considering different risk-taking behaviors of pedestrians. Simulation results show an overall improvement in the waiting time of vehicles and thus in the intersection throughput, compared to conservative vehicle behavior. The simulation results show also that the benefit of reduced waiting times for vehicles comes at the cost of some waiting time for pedestrians. However, the observed pedestrian waiting times in this model are not more than the generally accepted waiting times reported in empirical studies. [ABSTRACT FROM AUTHOR]

Highlights • Iterative transform simulation is proposed to reduce the computational complexity of image matching. • A geometric method to evaluate the homography matrix is proposed to filter out wrong matching results. • Superior performance in terms of speed while maintaining accuracy in matching oblique aerial images. Abstract This paper presents a fast and accurate method for matching oblique aerial image pairs. In order to achieve accurate matching results, we must consider viewpoint differences between the input images in addition to rotation and scaling. Existing methods that match aerial image pairs with viewpoint differences undergo heavy computation and have difficulty finding correspondences. In this paper, we propose a homography matrix evaluation method based on a geometric approach to increase the accuracy of image matching results. In addition, we achieve faster matching through an iterative transform simulation that reduces computational complexity. Experimental results show that the proposed method improves aerial image matching in terms of computational efficiency while achieving successful matching results. [ABSTRACT FROM AUTHOR]

Abstract The lifted sample-time approach has been extensively applied to analyze the behavior of a Networked Control System (NCS) under instances of packet-drop and/or variable communication latency (jitter) of varying durations. This paper combines the simplicity of the lifted sample-time approach in modeling an NCS under arbitrary but bounded instances of packet-drop and/or jitter with the proven L 2 induced norm based approach of controller design to realize an NCS which is capable of preserving the designed value of the norm under assumed conditions of packet-drop and/or jitter and hence a satisfactory time response under these conditions. The design methodology presented in this paper assumes a state feedback controller and uses a simple criterion based on a Linear Matrix Inequality (LMI). The methodology is validated using credible offline and real-time simulations. Highlights • Lifted sample-time approach for NCS is used. • Stability and time response is analyzed using MSFC to control the plant over network under jitter and packet-drop. • LMI based methodology to analyze the stability and controller design for NCS has been proposed. • The LMI formulations use a disturbance attenuation level as a specification for the lifting system. • The methodology has been demonstrated with credible offline and real-time simulations. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a speed sensorless control scheme named as finite control set-model predictive current control (FCS-MPCC) using a modified fictitious ohmic quantity (R) based model reference adaptive system (MRAS) for grid-connected doubly-fed induction machine (DFIM) drive. The variables of the reference model of this speed sensorless scheme (R-MRAS) are represented in stationary reference frame while those for the adaptive model are denoted in synchronously rotating reference frame. The sensorless formulation thus obtained is completely independent of any stator/rotor resistance terms. The scheme is also devoid of any stator/rotor flux estimation. Moreover, the intuitiveness of FCS-MPCC brings in additional flexibility in comparison to the conventional control techniques like field oriented control (FOC) and direct torque control (DTC). The overall scheme demonstrates faster execution time than FOC/DTC based control of DFIM drive. The proposed control algorithm is simulated and tested for limited speed range application in MATLAB/Simulink. The validation of simulation results are further done by experimentation on a dSPACE-1103 based DFIM laboratory setup. Highlights • In this paper, MRAS based sensorless speed estimation of DFIM drive by FCS-MPCC is reported. • The estimation scheme insensitive to the changes in machine parameters. • The overall scheme demonstrates faster execution time than FOC/DTC based control of DFIM drive. [ABSTRACT FROM AUTHOR]

Highlights • The paper proposes a fast and accurate method for the angle of attack calculation. • This method could be used during the simulations without extensive post-processing. • The estimated lift and drag are very useful for understanding the power coefficient. • This method may be applied to analyse a variable pitch VAWT for design optimisation. Abstract The Angle of Attack (AOA) of the Vertical Axis Wind Turbines (VAWTs) blades has a dominant role in the generation of the aerodynamic forces and the power generation of the turbine. However, there is a significant uncertainty in determining the blade AOAs during operation due to the very complex flow structures and this limits the turbine design optimization. The paper proposes a fast and accurate method for the calculation of the constantly changing AOA based on the velocity flow field data at two reference points upstream the turbine blades. The new method could be used to calculate and store the AOA data during the CFD simulations without the need for extensive post-processing for efficient turbine aerodynamic analysis and optimisation. Several single reference-points and pair of reference-points criteria are used to select the most appropriate locations of the two reference points to calculate the AOA and It is found that using the flow data from the two reference points at the locations 0.5 aerofoil chord length upstream and 1 chord away from each side of the aerofoil can give most accurate estimation across a range of tested AOAs. Based on the proposed AOA estimation method, the performance of a fixed pitch and the sinusoidal variable pitch VAWT configurations are analysed and compared with each other. The analysis illustrates how the sinusoidal variable pitch configuration could enhance the overall performance of the turbine by maintaining more favourable AOAs, and lift and drag distributions. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we consider reaction–diffusion model with modified Leslie–Gower and Holling-type II functional response and by varying simultaneously three model parameters, our model exhibits different types of complex dynamics. This allowed us to delimit several bifurcation surfaces with higher codimension corresponding to: Turing, Turing-Transcritical, Turing–Bogdanov–Taken, Turing–Hopf–Andronov, Turing-Saddle–node. Moreover by varying at least three bifurcation parameters, we show that small variations in the ratio of the diffusion coefficients can significantly alter bifurcation structure. Finally, the paper ends with the emergence of spatio-temporal patterns via numerical simulations. These simultaneous parameter variations leaded to spatio-temporal local and global bifurcations which are always catastrophic. Our results give new insights about how simultaneous changes in environmental and life history parameters drive different distribution dynamics of predator–prey populations. This only underscores the importance of including global bifurcations in the analysis of food chain models. Such results can be used to improve ecological decision-making on species conservation. Highlights • We found five types of bifurcations in our model. • We have characterized the parameters that can lead to these bifurcations. • We characterized the complex domains of parameter space delimiting the different types of dynamics. • We have determined by simulation the types of dynamics corresponding to these instabilities. [ABSTRACT FROM AUTHOR]

Abstract The paper presents a quantitative modeling for delineating alteration zones in hypogene zone of Miduk porphyry copper deposit (SE Iran) based on drill core data. The main goal of this study is applying Sequential Gaussian Simulation (SGS) and Concentration-Volume (C-V) fractal model based on Cu grades to separate different alteration zones. In this study, 10 realizations were generated using the SGS modeling and C-V log-log plots were created for them to determine Cu threshold values which delineate alteration zones. Correlation derived from log ratio matrix, which was used to compare between geological and C-V fractal results, shows that Cu values less than 0.575% from simulation number 9 (sim 9) has more overlapped voxels with phyllic alteration zone by overall accuracy (OA) of 0.75. Furthermore, the comparison revealed that sim 9 with Cu values between 0.575% and 0.933% and OA of 0.88 can determine propylitic alteration. Spatial correlation between the potassic alteration zone resulted from 3D geological modeling and high concentration zones for the C-V fractal model shows that the alteration zone has Cu values between 0.955% and 1.380% (sims 2, 3 and 4) with OA of 0.71. Finally, based on correlation between classes in the geological and the fractal models of hypogene zone, this research resulted that potassic alteration, which is the richest zone, has a strong overlap with sims 2, 3 and 4 while phyllic and propylitic alterations, with lower grades, have an appropriate overlap with sim 9. Highlights • The paper presents a quantitative modeling for delineating alteration zones. • SGS and C-V fractal modeling were applied on Cu grades to separate different alteration zones. • Logratio matrix was applied to calculate spatial correlations between C-V fractal and geological models of alteration zones. [ABSTRACT FROM AUTHOR]

Highlights • A reduced-order FEHD model approach. • Computational savings while keeping accuracy compared to traditional EHD and TD. • Harmonic modeling and simulation of a stand-alone PV-battery-supercapacitor hybrid system. • FEHD subsystems involving distinct integration time-steps (slow or fast dynamics). • Verification of the proposed approach via PSCAD/EMTDC software tool. Abstract Simulation of stand-alone photovoltaic (PV) systems requires mathematical models that permit to reproduce systems' dynamics closely to actual components. Such accuracy helps engineers to evaluate power quality issues, e.g., harmonic transient analysis and total harmonic distortion, and to design control algorithms to fulfill the applicable connection codes. This paper proposes a model, aimed at harmonic transient simulation, of a stand-alone PV system that involves a battery-supercapacitor hybrid energy storage system. The proposed model is based on a recently introduced harmonic domain modeling technique, i.e., flexible extended harmonic domain (FEHD). This paper demonstrates that the proposed FEHD-based model keeps accuracy of harmonics dynamics while diminishing computational burden compared to time-domain and conventional extended harmonic domain based models. Two case studies, involving the aforementioned hybrid PV system, are presented and validated against the PSCAD/EMTDC simulation tool. [ABSTRACT FROM AUTHOR]

Highlights • The paper presents a PMU-based autoreclosing method. • The paper presents a comprehensive auto-reclosing method for all fault types. • The proposed method can enhance the reliability of distribution systems. • Effects of thermal stress and stability indices are investigated before reclosing. • The proposed method has been evaluated using real-time HIL simulation method. Abstract This paper presents an adaptive auto reclosing scheme (AARS), applicable to active distribution systems, which are equipped with Phasor Measurement Units (PMUs). The scheme differentiates between temporary and permanent faults by taking into account the operational conditions of the network when determining the reclosing dead time. The performance of the proposed scheme is assessed through a real-time hardware-in-the-loop (HIL) simulation test setup. [ABSTRACT FROM AUTHOR]

Abstract The article shows Generalized Interpolation Material Point Method numerical simulation of the Sainte Monique landslide. The simulation uses a strain-rate dependent Tresca constitutive model, extended with strain softening behaviour for structured clays. First, the paper replicates fall cone tests to validate the constitutive model and to select the material parameters. Afterwards, the paper shows the Sainte Monique landslide simulation which additionally considers shear band thickness to reduce the mesh-dependence. The results suggest that the strain-rate affects the prediction of the run-out distances and leads to the landslide acceleration-deceleration cycles (reported in, e.g. Corominas et al., 2005; Wang et al., 2010). [ABSTRACT FROM AUTHOR]

Abstract Mode I crack propagation in prestressed concrete sleepers B70 is simulated by a fracture mechanics approach. The plastic damage model, which takes the non-linear behavior of concrete into account, is utilized to calculate crack length and crack mouth opening displacement (CMOD). Numerical data from prestressed concrete sleepers B70 under three-point bending load are compared with those of the proposed fracture mechanics model. In this study, fracture mechanics parameters of prestressed concrete sleepers are investigated. Sleepers with the length of initiation crack of 5 to 45 mm (with 10 mm steps) and the width of initiation crack of 2 to 8 mm (with 2 mm steps) are analyzed. Sleeper cracks are created in the notch and both of its sides. These analyses confirm that the structural behavior of prestressed concrete sleepers can be predicted by a simple fracture mechanics model provided that the related material properties like KIC, crack length and CMOD, are known. Highlights • Fracture mechanics of pre-stressed concrete sleeper B70 is studied with numerical analysis. • We model B70 sleeper which have 5 crack initiation lengths and 4 crack initiation width in center of sleepers. • Force-Crack length and Force-CMOD diagrams are measured for notched sleeper models in center and sides of sleepers and compared together. • This paper follows sleeper B70 paper "F. Rezaei, S.M. Farnam, Fracture mechanics analysis of pre-stressed concrete sleepers via investigating crack initiation length, Eng. Fail. Anal, 58 (2015) 267–280". [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Systemic and systematic risk analysis and modelling. • Logic-based Artificial Intelligence to face increasing complexity of systems. • Risk Curve, Risk Spectrum (new), and Critical Functions List as practical tools. • Systemic and systematic verification of the efficacy of solutions to reduce risks. • Risk-based decision making as evolution of the opportunity-based approach. Abstract Making decisions in complex systems and for complex phenomena is a challenging task to accomplish. As complexity and uncertainty increase, the use of scenarios to exploring that uncertainty becomes essential to support decision makers. Yet, the increasing complexity of and interrelatedness amongst systems/phenomena is imposing to the risk analysis world a paradigm shift from traditional, "paper and pencil" approaches toward simulation-based approaches, not least because the cognitive demand required to envisage all the possible alternatives the system/phenomenon might unfold is too high to manage for the human mind. The paper presents how the Holistic Risk Analysis and Modelling (HoRAM) method allows, on the one hand, to holistically account for the Human, the Technological and the Organisational (HTO) elements of the system/phenomenon being analysed and, on the other hand, thanks to the use of artificial logic, to create complete partitions of sizes that are unthinkable to achieve with traditional, paper and pencil methods. The paper also explains how the method allows to systemically and systematically account for the consequences scenarios might generate, thus allowing to include in the decision both the possibility of the unwanted outcomes and the associated effort needed to make them less likely or less severe. Finally, it explains how the scenarios can be managed at different level of abstraction to deriving the well-known risk curve, the newly defined risk spectrum, and the critical functions list, which are all necessary tools to better discriminating which alternative to pursue and where exactly investing the (always limited and scarse) resources to reduce the risk. [ABSTRACT FROM AUTHOR]

Highlights • This paper constructs a bi-level programming model, the plan of no investment is incorporated and the capital recovery factor is introduced. • An efficient and effective simulated annealing algorithm is proposed and applied for solving the model. • A large-scale China railroad system, which is one of the largest railway networks in the world, is used to test our method. Abstract This paper proposes a bi-level programming model for the multi-classification-yard location (MCYL) problem. The upper-level is intended to find an optimal establishment or improvement strategy for candidate nodes with a budget constraint, which is involved with the selection of potential yard locations and the determination of yard size and capacity. The lower-level aims to obtain the least costly plan of railcar reclassification considering yard classification capacity and tracks, on the basis of the strategy given by the upper-level. A simulated annealing (SA) algorithm is then applied to solve the MCYL problem of a large-scale China railway network. [ABSTRACT FROM AUTHOR]

Highlights • An inverse heat transfer model linked to Bayesian statistics is presented. • This model is used to identify the conductivity and volumetric heat capacity. • In situ measurements are used by the inverse model. • The proposed model can use shorter time series than the standard ISO 9869. • The proposed model produces more accurate and robust results compared to the standard. Abstract Non-destructive thermal diagnosis is necessary for identification and quantification of structural defects and verification of construction performances. In this paper, we test different inverse heat transfer models to identify the thermal conductivity of a building's wall in its environment. The approaches proposed and used in this paper rely only on non-intrusive measurements: inside and outside wall surface temperatures and heat flow through the wall. First, a Bayesian statistical dynamic inference method, which has the advantage to quantify the unknown parameter and its credible interval, is presented. This method considers the uncertainties of the measured temperature and heat flow data and of the unknown thermal properties. Markov chain Monte Carlo (MCMC) algorithm is used to explore the posterior distribution. Then, the average and the dynamic procedures ISO 9869 (I. 9869-1, 2014) are introduced. Finally, the probabilistic distributions of the unknown parameters are presented and compared to the standard results. The impact of experimental conditions (average indoor-to-outdoor temperature) and the measurements length on the accuracy of the results are discussed. The relationship between the number of iterations of the MCMC , time series length, shape of the prior distribution and accuracy are studied as well as the simulation time to run the inverse models. The Bayesian approach gives the most accurate results and has the advantage of considering several unknowns (conductivity and volumetric heat capacity), which is not the case for the studied standard. The Bayesian method needs much shorter time series than the ISO standard and produces robust results at all times of year, including when the average indoor-to-outdoor temperature difference was low. [ABSTRACT FROM AUTHOR]

Abstract In recent years, more and more existing building has an ever increasing requirement of retrofit, which has been developed from individual measure to combination package of multiple measures. It has become the challenging task for screening building multiple energy retrofit measures package (BMERMP). In this paper, a stepwise screening methodology for BMERMP is proposed considering economic and risk aspects, which integrates Life-Cycle Cost (LCC) and Monte Carlo (MC) analysis. First of all, this paper puts forward a calculation reference table for energy saving retrofit potential. In addition, this paper also uses unit energy saving incremental cost (UESIC) to screen technology and suggests economic internal rate of return（EIRR）as cost-benefit analysis index of BMERMP. Furthermore, the authors propose the concept of Value-at-Risk (VaR) as an effective measure to control the risk. The VaR for EIRR is determined by risk variation and can be obtained through MC simulation. Meanwhile, the study takes a commercial building for example, this building comprises 19 measures in initial BMERMP by energy diagnosis and the VaR of initial BMERMP is 97.6%, which has a high risk. According to the ranking of UESIC value, when 4 high cost technologies are reduced, the VaR can be reduced to 0.07%, then the economy of BMERMP is feasible and the risk is controllable. This paper provides a new perspective for the decision maker to select BMERMP. Highlights • A stepwise screening methodology to select building multiple energy retrofit measures package (BMERMTP) is proposed. • The screening methodology integrate Life-Cycle Costing(LCC) and Monte Carlo(MC) analysis. • Cost-benefit analysis for BMERMTP adopt the economic benefits of energy retrofits in the economic period. • Present the concept of Value-at-Risk (VaR) as an effective measure to control the risk for BMERMTP. • It suggests calculation table for building energy-saving retrofit potential. [ABSTRACT FROM AUTHOR]

Abstract In recent years, the application of imaging satellites has entered a completely new stage, with the new demands such as rapid response to emergency events, observation of large-scale regional targets and multivariate data fusion, the multi-autonomous satellite constellation has been proposed. This paper first designs the structure of multi-autonomous satellite constellation, and a centralized-distributed structure is proposed. This structure could improve the dynamic response capacity of the whole constellation. Then, this paper adds adapted filtering mechanism to single autonomous satellite online scheduling algorithm to enhance its performance. This article also pays more attention on task allocation strategies of the master satellite in constellation, and ten different task allocation strategies based on five dimensions are analyzed by simulation experiments. At last, this paper extracts several characteristic features of the regular observation targets and designs a selector based on support vector machine (SVM). This selector could select an appropriate strategy according to the features of each experiment scenario. [ABSTRACT FROM AUTHOR]

-->Graphical abstract Highlights • Conceptual design of a biorefinery, simulation and economic evaluation. • High-value biochemicals boost the profitability. • Novel esterification processes by heterogeneous catalysis and reactive extraction. • Pure glycerol co-product drops significantly the price of biodiesel. • Energy saving of 77% by pyrolysis using mechanical vapour recompression. Abstract The paper presents the conceptual design of a castor oil biorefinery. Castor oil contains over 90% ricinoleic acid (12-hydroxy-9-octadecenoic) triglyceride, a versatile functional molecule. Fatty methyl ricinoleic ester (FAMRE) is the key building block. This can be valorised as biodiesel, but more profitable is making biochemicals, namely high-value polyamides. The goal is the conceptual design, simulation and economic analysis of a biorefinery processing 80 ktpy castor oil, equally shared between biodiesel and biochemicals. The process synthesis work is based on research papers and patents, supported by simulation with Aspen Plus™. The biorefinery involves three plants: transesterification, pyrolysis and amination. Two innovative technologies are developed for transesterification, by heterogeneous catalysis in variable-time PFR and by homogeneous catalysis in reactive-extraction device. The reactors are simulated by employing detailed kinetics such that the ester composition fulfils the specifications set by the quality norms for biodiesel. Both methods result in compact and low energy processes, but the first delivers more valuable high-purity glycerol. FAMRE pyrolysis supplies heptanal, a valuable intermediate for specialities, and methyl undecenoate, converted further to ω-aminoundecanoic acid. Energy saving of 77% is achieved by employing mechanical vapour recompression. The amination is complex as chemistry and processing, involving aqueous solutions and solids. The economic analysis estimates capital costs and minimum product prices for 20% ROI. The performance and contribution of each process is highlighted. The bottleneck in design is the amination plant, capital-intensive and handling large amounts of process water. This stage makes necessary high equipment and energy costs but delivers a high-value monomer that boost the profitability. The result is that at equal throughput the biochemicals bring 2.5 times more revenues than biodiesel. By a synergy effect, high-value biochemicals sustain the profitability of commodity biodiesel, which in turn offers a broader market and secures stable revenues for farmers. [ABSTRACT FROM AUTHOR]

Abstract This paper provides an overview and tutorial on the key behaviors of mechanical friction in both the time and frequency domains to understand friction effects on precision motion control systems, and presents implications of this behavior for high-precision applications. Friction behaves differently depending on the operating regime. In the steady sliding regime, friction is a function of the relative velocity of two objects sliding against each other, and characterized by static, Coulomb and viscous terms. We observe more complex frictional behaviors as the velocity and displacement are near zero, which is the pre-sliding regime. Friction in this regime depends on the displacement of objects in contact, acting as a nonlinear hysteretic spring. In this paper, we focus on the time- and frequency-domain phenomena caused by the nonlinear hysteretic elasticity of such pre-sliding friction. Frictional microdynamic behaviors in each domain are experimentally studied with a servomotor system testbed and using the Generalized Maxwell-Slip (GMS) friction model. Friction model identification methods based on experimental observations are also discussed in both the time- and frequency-domains. We also present structures for accurate time-domain simulation of friction. Highlights • Coulomb model, widely used to compensate friction, creates regenerative errors. • Understanding friction micro-dynamics is critical in high-precision motion systems. • Pre-sliding friction acts as a nonlinear hysteretic spring, deteriorating accuracy. • Frictional hysteresis and resonances are demonstrated in simulation and experiment. • Time- and frequency-domain parameter identification methods allow model fidelity. [ABSTRACT FROM AUTHOR]

Abstract The piezoelectrically-actuated inertial stick-slip device (PAISSD) is widely used in the field of nanotechnology because of its high resolution and theoretically unlimited displacement. However, it suffers from such problems as a small driving force and low velocity. In this paper, an optimized driving waveform is proposed to increase the velocity. The optimized driving waveform includes a second order driving waveform, the step response of the waveform, and a buffer waveform that can effectively improve the velocity. First, the driving waveform optimization is proposed and a kinematic model of inertial stick-slip driving is established. Then the effects of various waveform parameters on PAISSD performance are determined and optimal parameters are selected via simulation. Finally, the kinematic model is validated and the effectiveness of the driving waveform optimization is demonstrated experimentally. We achieve higher velocities and larger single-step displacements than those provided by the traditional driving waveform, a sawtooth wave. Results show that the waveform optimization-driven single-step displacement and velocity are remarkably effective. Highlights • The driving waveform is optimized and analyzed based on the principle of inertial stick-slip driving in this paper. • The kinematic model of single-step displacement and velocity is established and is validated. • The single-step displacement and the velocity have been raised 2.1 times and 1.5 times. [ABSTRACT FROM AUTHOR]

Abstract Computer controlled ultra-precision polishing (CCUP) is widely used for high-precision surface finish processing with high form accuracy and good surface finish. CCUP is a deterministic material removal process based on the surface error-profile and the removal characteristic of the polishing tool. Material removal profile is often used to characterize the material removed in polishing process. Deviation phenomenon is a newly detected feature of the material removal profile which may contribute to the non-negligible form error of the polished surface. In this paper, the material removal model is established on the basis of Preston equation to obtain a better understanding of the characteristics of material removal in surface polishing. Firstly, contact stress model is established using Hertz contact theory. Then, relative velocity in the contact area is analyzed using geometric methods which can directly reflect the difference of the velocity of points in the contact area. Finally, single factor analysis and Taguchi method are used to investigate the influence of polishing parameters on the deviation feature of material removal profile and to provide a way for parameter optimization. The simulation and experiment results indicate that the proposed method can describe the deviation features well and parameter optimization strategies are provided in the conclusions. Highlights • The relative velocity model is established using geometric method taking the deformation of the polishing tool into consideration. • Newly defined index is used to evaluate the deviation characteristics of the material removal profile. • This paper provides a basis for parameter optimization strategies for uniform material removal in CCUP. [ABSTRACT FROM AUTHOR]

Abstract Solar aided (coal-fired) power generation (SAPG) system has been proved to be an efficient way to utilize the solar energy for power generation. Due to the instability of the solar radiation, a SAPG system generally operates under transient working conditions. In this paper, performance simulation sub-models of main components in a SAPG plant are established based on the lumped parameter assumption. A 330 MW SAPG power plant as a case study is simulated. The variations of the performances, main parameters of the plant with the solar field heat output and the dynamic responses under a typical day are analyzed. The results show that when the heat output of the solar field changes from 0 kJ/h to 2.13 × 108 kJ/h, the coal saving rate will increase to 6.4%, and the solar power generation share (the proportion of the power from the solar energy to the total power from the SAPG plant) will increase to 7.74%. During the analysis process, in order to optimize the solar field, the concept of the solar field equivalent efficiency (SFEE) is proposed and the optimal velocity of heat transfer fluid (HTF) in absorber tube is obtained. Highlights • The transient model of a solar aided power generation (SAPG) system is developed. • The concept of solar field equivalent efficiency (SFEE) is proposed in this paper. • The optimal velocity of heat transfer fluid in the absorb tube is obtained. • Performances of SAPG system with different solar field heat output are revealed. • The dynamic responses of the SAPG system under a typical day are analyzed. [ABSTRACT FROM AUTHOR]

This paper proposes a novel simultaneous control interface and protection scheme for DC microgrids (DCµG) interconnected systems, although the interconnections could be possible via two power electronic systems such as DC/DC converter. Each DCµG presented in this paper is supplied by AC grid as well as battery bank unit, distributed generation (DG) unit and AC load unit. The proposed control interface is based on a developed suitable small signal model for each DCµG that provides proper power flow control and cancellation of interactions between DCµG. Also, the presented protection scheme for fast fault detection in DC link is based on fuzzy inference system (FIS), so that faults could be detected as quickly as possible in few milliseconds. In fact, the aim of this paper is simultaneous protection and control interface for DC multi microgrids, so that the performance of the controller and protection system is separate, yet integrated together. As such, DC multi microgrid performance under different events, such as change in active power of DGs and short circuit is not in trouble and disorder. Simulation results indicate the remarkable effectiveness of the proposed control interface and protection scheme for DCµG interconnected systems. For validation of the capability and feasibility of FIS fault detection scheme, simulated network and protection algorithm are implemented in laboratory-scale. The implementation results demonstrate that FIS protection scheme can swiftly detect faults within a few milliseconds. [ABSTRACT FROM AUTHOR]

Highlights • Measurement of water content of oil-water flows using dual-frequency microwave. • A dual frequency correction algorithm was proposed. • Deep neural network predicts complex nonlinear mixture permittivity. Abstract This paper presents a microwave dual frequency correction algorithm to measure the water content of the oil-water two-phase flows, which can eliminate the influence of conductivity and obtain the water content. Subsequently, based on the advantages of dual-frequency this paper proposes a deep neural network model to predict complex nonlinear relationship between the mixture permittivity and water content. In order to avoid falling into a local optimal solution, the adaptive moment estimation algorithm is used to replace the gradient descent method. The experimental results are applied to estimate the performance of the discussed deep neural network algorithm. [ABSTRACT FROM AUTHOR]

Abstract In this paper, both switches open/short circuit faults diagnosis and a fault tolerant diagram of a photovoltaic (PV) fed Three-Level Boost DC-DC Converter (TLBDC) are addressed. Diodes voltages are used to detect open or short circuit faults. These voltages are also used to ensure voltage balance control of the TLBDC. Hence, the number of sensors would be the same as the number of sensors used in a conventional TLBDC controller scheme. The proposed method identifies and locates the faulty switch easily. The TLBDC is reconfigured where the ensured input power and output voltage remain unchanged. This is achieved by adding only one extra power switch to the TLBDC topology. Simulation and experimental results confirm the effectiveness of the proposed fault diagnosis method and the TLBDC fault tolerant scheme. Highlights • This paper studies a fault detection method and tolerant strategy for three-level boost DC-DC converter. • The strategy is a low cost option and uses the same sensors number as used for normal operation. • After reconfiguration, the input power and output voltage are the same as in the post fault. • The results show the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

Abstract PID controllers are still widely practiced in the industrial systems. In the literature, many publications can be found considering PID controller design for unstable processes. However, owing to the structural limitations of PID controllers, generally, good closed loop performance cannot be achieved with a PID for controlling unstable processes and usually a step response with a high overshoot and oscillation is obtained. On the other hand, PI–PD controllers are proved to give very satisfactory closed loop performances for unstable processes. The paper presents a simple design method to tune parameters of a PI–PD controller for the control of the unstable processes with time delay. The proposed method is based on plotting the stability boundary locus, which is a locus dependent on the parameters of the controller and frequency, in the parameter plane. The method uses a new concept named centroid of the convex stability region. Simulation examples and an experimental application are given to illustrate the superiority of the proposed method over some existing ones. Highlights • The paper represents a novel method for PI–PD control of the unstable systems. • The proposed method uses a new concept named centroid of convex stability region. • Ability of being extended to uncertain plants of the proposed method by means of Kharitonov theorem is an important advantage. [ABSTRACT FROM AUTHOR]

Mould growth on building materials is a complex phenomenon involving various causes environmental conditions including temperature and relative humidity, nutrients, exposure time. Environmental conditions and nutrient are closely related to physical properties of building materials. Thus, the appropriate selection of building materials is very important for prevention of adverse health effects due to mould growth. The aim of this study is to determine the influence of the hygric properties of interior finishing materials on the mould growth. This paper presents the results of mould growth risk evaluation with variation of hygric properties of interior finishing materials using hygrothermal and bio-hygrothermal simulation approaches. An experimental study was conducted to characterize the hygric properties of wallpapers which are used mainly as interior finishing material in residential buildings. Six types of wallpapers and two type of hygric properties (water vapour transmission property and moisture storage function) were selected for the study. WUFI Plus was selected for a whole building hygrothermal simulation. The results from the hygrothermal simulation were used for the assessment of mould growth risk using a biohygrothermal calculation model, WUFI-Bio. The simulation results show the clear correlation between the mould growth rates and the hygric properties of wallpapers. [ABSTRACT FROM AUTHOR]

Highlights • To our knowledge this is the first journal paper to include in-depth thematic analysis of expert interviews regarding the use of building performance simulation in Australia, with a particular focus on lower quality office buildings. • In this paper, the typical simulation and upgrade process operating in practice in Australia is compared with a previously outlined optimal strategy, and a 'Revised Systematic Approach' to sustainable building retrofits is proposed. • The thematic analysis of interview responses identified many of the drivers and barriers influencing the user of building simulation tools. • Several practices employed by practitioners that are likely to greatly increase the uncertainty associated with simulation results were identified. • The lack of reliable and accurate data was highlighted as a key issue facing this sector, and the implications of the uncertainty introduced by the necessary use of assumptions, particularly concerning innovative financing initiatives, is discussed. Abstract Building Performance Simulation (BPS) has become an important tool in the upgrading of the existing commercial building stock. It allows a user to predict energy savings from upgrades, and thereby optimise the energy, financial or other benefits of an energy efficiency upgrade. The current paper presents the findings from a qualitative investigation into the use of BPS in the Australian commercial building retrofitting industry. The interviews had a particular focus on challenges for lower quality (known as secondary grade or mid-tier) office buildings. Twelve semi-structured interviews were undertaken with stakeholders in the building energy retrofitting industry, including consultants, government administrators and building managers. Thematic analysis of the interview data revealed numerous challenges for BPS users, primarily related to the lack of reliable, accessible data regarding building operations and energy use in Australia. The poor data availability encouraged the use of simulation to inform decisions but required the modeller to use assumptions and heuristics to develop the model. This, in turn, necessitated a reliance on the expert knowledge of the simulation user, and made the interrogation of a building model by a third party problematic. [ABSTRACT FROM AUTHOR]

Highlights • Constitutive equations for a vertical rod bundle are reviewed. • Dependence of distribution parameter on flow conditions is discussed. • 1D momentum equation by considering void fraction distribution is discussed. • Effect of channel size on interfacial area concentration is discussed. Abstract In view of the quality assurance of two-phase flow simulations, CSAU (Code Scalability, Applicability, and Uncertainty) methodology and code V & V (Verification and Validation) have been proposed. The estimation of simulation uncertainty is indispensable in using best-estimate computational codes. A key of successful two-phase flow simulations is to use the state-of-the-art constitutive equations to close the mathematical system used in two-phase flow analyses. The advanced constitutive equations should be developed based on “physics” behind phenomena and should consider scaling parameters which enable their application beyond test conditions used for a code validation. Two-phase flow simulations in a rod bundle is important in various industrial apparatuses such as heat exchangers and nuclear reactors. Constitutive equations for two-phase flows in a vertical rod bundles have been advanced in recent five years. In view of this, this paper provides a comprehensive review of most advanced constitutive equations for two-phase flow analyses in a vertical rod bundle. The constitutive equations of two-phase flow parameters reviewed in this paper are flow regime map, void fraction, void fraction covariance and relative velocity covariance, interfacial area concentration and wall friction. In addition, an exact formulation of one-dimensional momentum equation in two-fluid model considering void fraction distribution is discussed. [ABSTRACT FROM AUTHOR]

Abstract Immersive Virtual Reality-based collaborative BIM 4D simulation can offer a unique, supportive environment for conducting constructability analysis meetings in the construction industry. While many research works have addressed various aspects of VR-based 4D simulation, there is still no comprehensive and neutral framework to help both practitioners and experts to identify the main challenges to address. This paper proposes four main complementary steps with which to define the VR environment, to develop the 4D model, to prepare and transfer the model in the VR system and to conduct constructability analysis meeting. In the current state of the framework, the 4D-based constructability analysis is more about the collaborative use of 4D rather than the collaborative generation and interaction with the 4D model. Each step of the framework is supported by appropriate methods and tools. A collaborative personas-based case study helps to evaluate the framework and to show how it can be used. Compared to recent related works, the proposed framework is more structured and comprehensive, providing a structured approach using concepts from multiple scientific areas. Highlights • The article proposes to support constructability analysis meetings with immersive VR-based collaborative 4D simulation. • The framework presents a detailed process for passing a 4D simulation from Navisworks into an immersive VR environment. • It uses collaboration personas theories to describe the definition of the practitioners' needs and the VR environment. • The paper presents innovative metamodels to support the use of the proposed framework. [ABSTRACT FROM AUTHOR]

Abstract The control-oriented modeling and real-time simulation method for a dual-mode scramjet combustor has been conducted in this paper. The 1-D unsteady model coupled with isolator shock train model and oblique shock wave modification can treat variable area, fuel addition, combustion heat release, variable specific heat, inflow air vitiation component, wall friction and mixing efficiency. Combustion is simplified into mass and heat addition process. So this paper discusses heat release distribution obtaining method which can be applied in scramjet combustor 1-D flowfield simulation in detail. It is fit for certain scramjet combustor configuration and acceptable over a wide range of inflow conditions. By mixed programming of C and Matlab, the code of model solving is capsuled into S-Function which can be used in SIMULINK. The control-oriented model is built on SIMULINK platform. When the model runs in a single-core 3.6 GHz Intel Core i7-4790 processor, computation time-consuming is found to require 5–10 ms within a control period. The computing speed indicates very promising, because model is compact enough to run in real time, and it can be used as an embedded model in control system research. This model can also be used to analyze unsteady and steady flowfield characteristic. The safety boundary codetermined by unstart and over-temperature is conducted using this model. Highlights • Control-oriented 1-D unsteady model was presented for dual-mode scramjet combustor. • By mixed programming, real-time model was built on SIMULINK platform. • The heat release distribution obtaining method was discussed and explained. • The unsteady, steady flowfield process and safety boundary were analyzed. [ABSTRACT FROM AUTHOR]

Abstract On-Orbit Servicing (OOS) is becoming more extensively discussed in research and commercial developments. The key point of servicing relies on the relation between two systems, the Servicer executing the tasks and the Client being serviced. With the increase of interest in OOS applications, the exploration of the Client-Servicer relationship in different scenarios becomes a necessary step in servicing implementation. Exploring such a relationship involves translating the information available about OOS into useful inputs for spacecraft design, a challenging task due to the variety of applications and possible interactions between both sides. Then, different modelling and simulation techniques can be used to model and to explore the interaction of such complex systems for different scenarios of servicing. This paper presents an agent-based framework to explore the relations of Servicer and Client for applications of On-Orbit Servicing. To do so, the case for a hypothetical satellite operator is explored, under a specific set of requirements and conditions for different servicing solutions. First, the Agent Based Modelling and Simulation (ABMS) is established based on a specific set of rules, definition metrics and operation characteristics relating Servicer and Client. Then, the basic assumptions of Client, Servicer and servicing operations are discussed and the initial simulation parameters are defined. The ABMS is used to simulate OOS for a fleet of geostationary communication satellites for the cases of Lifetime Extension , Refuel and Rescue and Recover. In the end, the ABMS outputs are used to explore the design aspects of the Servicer and Client satellites at systems level. The results highlight the advantages of having this type of framework for early assessment of OOS under different types of context for both Servicer and Client. The paper concludes with directions of how the framework can be used to explore more complex and realistic scenarios of OOS, and assess their potential benefits. Highlights • Framework to explore the Servicer-Client relationship in On-Orbit Servicing. • Concurrent approach of Client and Servicer points of view is necessary. • Systems' technical and financial metrics build a more solid analysis of servicing. • Consideration of different servicing applications and capabilities. • Parameters to assist during the decision making process towards servicing. [ABSTRACT FROM AUTHOR]

Abstract The cured in place pipe (CIPP) liner technology is to install flexible polymeric liners with thermosetting resin inside existing pipelines. Compared with traditional methods of pipeline retrofits, CIPP provides an economic and environmentally friendly alternative for pipeline rehabilitation. However, the lack of proper constitutive models of the push-on joints and the CIPP-liner reinforced joints remains a critical deficiency in current numerical simulations of buried segmental pipelines. This paper presents new constitutive models of ductile iron (DI) push-on joints, before and after reinforced with one type of the CIPP liners, commonly used in pipeline retrofits. The proposed models were calibrated from the full-scale quasi-static tests performed on water-pressurized DI pipelines with push-on joints. These new joint models, considering strength degradation and energy dissipation of the joint, well characterizes the longitudinal behavior of the push-on joint and the liner-strengthened joints under repetitive axial loading, which primarily represents the expansion and contraction effects of the joints due to thermal effects or seismic waves traveling along the buried pipelines. Moreover, this paper also provides a rational procedure for evaluating the seismic performance of buried pipeline with different push-on joints. The proposed numerical procedure could be generally applied to quantify the seismic performance of buried straight pipelines incorporating the proposed joint models under seismic wave propagation. Numerical results indicate that the CIPP liner can significantly improve the seismic performance of the push-on joints subjected earthquake induced transient ground deformations. Highlights • Hysteretic joint models were developed to capture the axial response of ductile iron push-on joints before and after retrofit with the CIPP liner. • A numerical procedure is proposed for assess the seismic performance of straight buried pipelines subjected to seismic loadings. • CIPP liner can effectively improve the seismic performance of the segmental pipelines with push-on joints subjected seismic wave propagation. [ABSTRACT FROM AUTHOR]

Highlights • Set-up of a physics-based model to predict the performance curves of pumps as turbines. • The model is calibrated on experimental data from four centrifugal pumps taken from literature. • The predicted performance curves are physically consistent over the entire range of operation. • Model prediction error is acceptable, compared to other methods available in literature. • The physics-based model is powerful and reliable to estimate PAT complete performance curves. Abstract This paper presents the development of a physics-based simulation model, aimed at predicting the performance curves of pumps as turbines (PATs) based on the performance curves of the respective pump. The simulation model implements the equations to be used for the estimation of head, power and efficiency for both direct and reverse operation. Model tuning on a given machine is performed by using loss coefficients and specific parameters identified by means of an optimization procedure, which is first applied to the considered pumps and subsequently to the same machine running in PAT mode. The simulation model is calibrated on data taken from literature, reporting both pump and PAT performance curves for head, power and efficiency over the entire range of operation. The performance data were acquired experimentally from four different centrifugal pumps, running in both pump and PAT mode and characterized by specific speed values in the range of 1.53–5.82. The accuracy of the predictions of the physics-based simulation model is quantitatively assessed against both pump and PAT experimental performance curves. Prediction consistency from a physical point of view is also evaluated. The results presented in this paper highlight that all the performance curves predicted by the simulation model are physically consistent over the entire range of operation. In general, the prediction error on the head of PATs is acceptable, while the accuracy of the prediction of PAT power, and thus of PAT efficiency, is more case-sensitive and usually higher. The relative deviation of model prediction with respect to the field data regarding head and power at the PAT best efficiency point always seems acceptable compared to the uncertainty of the original experimental data and to typical deviations of other methods available in literature. As a conclusion, the physics-based simulation model developed in this paper represents a powerful and reliable tool for estimating PAT performance curves over the entire range of operation based on pump characteristics. [ABSTRACT FROM AUTHOR]

Abstract This research paper is developed as a practical guide on preparedness against possible threats that are usually unconsidered or undermined in Egyptian conservation schemes and agendas. The unequivocal importance of the Karnak temple (KT) in Luxor, Egypt presented this monument as a major target for investigation. Reviews of recent conservation endeavors in the KT unveil a clear lack of awareness concerning preparedness against fast, sudden and unpredictable threats. The preparedness plan developed in this research paper for the KT tackles the relationship between sources of threats, past disaster incidents, inducible risks and the process of generating interventions to contain risks and minimize damages. Issues of scientific uncertainty are transcended for the greater aim of preparing a preparedness plan against possible and potentially harmful threats. [ABSTRACT FROM AUTHOR]

Abstract Mobile crowdsensing has become an efficient paradigm in which crowd workers are recruited to collect data by using their mobile smart phones. However, different workers may provide data with varied degrees of quality. Therefore, it is imperative to develop a reliable crowdsensing system that guarantees the quality of service (QoS) for each task. In this paper, we propose a Reputation-based Multi-Auditing algorithmic mechanism (RMA) by integrating Task-based Temporal Reputation mechanism (TTR) and Reputation-based PM truth inference algorithm (RPM). Further, Performance-Based Payments scheme (PBP) is adopted to promote truthful workers. Based on the past benefits, the behavior of a rational requester may vary over time. Particularly, reinforcement learning and (1- ϵ) accuracy algorithm are used to model the update policy of a requester's strategy. Both rational and irrational workers are considered in this paper. Depending on whether a worker can perceive the benefits of other workers, K-armed bandits and neighborhood learning mechanism are respectively adopted to model the update policy of rational workers. By using Lyapunov stability theory, it is qualitatively proved that the trustful provision of sensed data provides an unique stable evolutionary equilibrium for each rational worker in our proposed system. Finally, extensive simulations and real data experiments illustrate that the RMA mechanism has an outstanding performance on discovering truth and achieving profits. [ABSTRACT FROM AUTHOR]

Highlights • The asynchronous bipartite consensus for a group of agents with second-order dynamics is examined in this paper. • The properties of the product of infinite time-varying row-stochastic matrices from a noncompact set are explored to analyze this problem. • A sufficient condition that depends on switching topologies is established. Abstract The asynchronous bipartite consensus for a group of agents with second-order dynamics is examined in this paper, where the asynchrony means that the time instants when each agent receives the neighbors’ data information are completely independent of other agents’. The communication among the agents is described by a time-varying signed and structurally balanced digraph, which is equivalent to assuming that the agents can be divided into two groups without any common agents, in which the agents within the same group are cooperative and the agents between different groups are competitive. An asynchronous distributed control protocol is designed to implement the bipartite consensus. By using the product properties of row-stochastic matrices from a noncompact set, a sufficient condition can be established under a loose assumption that is the union of communication topologies related to any time intervals with given length has a spanning tree. Finally, a simulation instance is provided to verify the reachability of asynchronous bipartite consensus. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • This paper addresses the design of Kaibel and multi-sidestream column. • The multi-sidestream column is the most energy-efficient configuration. • The control structure of three distillation system is presented. Abstract Due to the conventional sequence has a disadvantage of high energy consumption, this paper proposes the optimal design and control of the Kaibel and multi-sidestream column for separating five-component hydrocarbon mixture. First, three processes are simulated by steady-state simulation. The three distillation structures are designed by minimizing the total annual cost (TAC) and the results show that the multi-sidestream column is the most energy-efficient configuration, with savings of 29.5% to the conventional sequence, and 12.2% to the Kaibel dividing wall column (KDWC). Second, the suitable control of three processes are designed. The temperature controller is used in multi-sidestream column and the component controller is used in KDWC. The results show that the response time towards disturbance of the KDWC is longer and the purity of the multi-sidestream column is not up to the requirement. Finally, aiming at the problem above, the control structures of KDWC and multi-sidestream column are optimized. Temperature controller is added in the KDWC instead of the component controller. Under the control of temperature, it can return to stable in a short time. A double temperature controller is added in multi-sidestream column based on defects of basic control structure. Its product purity can attain above the designed value. Compared to the multi-sidestream column process, the control structure of KDWC can handle feed disturbance more effectively, and the purity is closer to the design value. [ABSTRACT FROM AUTHOR]

Banyan network is a multistage communication architecture that route the input signal based on port address of receiver. The port address is recognized as a string. This paper illustrates the design of a novel single layer banyan network using QCA for nanocommunication. To design the proposed communication architecture, a new single layer 2-inputs and 2-outputs crossbar switch is proposed and implemented in QCA. Using this crossbar switch as a major building block, a 4x4, and 8x8 banyan networks have been achieved in this paper. The effect of stuck-at-fault at the control input is observed and excelled for fault free design of the crossbar switch. Similarly, the fault tolerant nature of the proposed banyan networks have been characterized by considering the stuck-at-fault effect at the control signals of crossbar switches within the architecture. The designs are evaluated considering device area, delay, and logic gates. Theoretical values have been matched up with the simulation results to verify design accuracy. [ABSTRACT FROM AUTHOR]

IEC61850 protocols aim to reduce the data management with a bandwidth that does not present any issues. Fast tripping protection schemes using IEC 61850 will lead to network flooding, high delay, and reduced network security. The study provides propagation characteristics of traveling wave with extra high-speed busbar protection in compliance with IEC 61850 technique. This paper analyzes the process bus and suggests two methods in order to achieve the intended fast protection with IEC 61850. The simulation of the suggested methods based on the OPNET Modeler has proven that these methods can solve the network flooding problem in Ethernet and band-limited channels such as WLAN. This study will pave the way for researchers to reuse the traveling waves for fast protection with IEC 61850. In this paper, the simulation results of the case study busbar protection using transient signal (traveling wave) based on IEC 61850 network system configurations using OPNET Modeler simulation software were presented and the influence of data rate, a number of MUs sharing process bus and delay characteristics of these system configurations were evaluated. [ABSTRACT FROM AUTHOR]

In probabilistic durability design of concrete structures in marine environment, the limit state is defined as the corrosion initiation of reinforced steel. However, the owner may more concern the cracking growth of concrete surface or the first repair time without maintenance, in that case, additional information on surface deterioration should be supplemented to eliminate owner’s concern. This paper employs the two-dimensional simulation method to predict the surface deterioration process for reinforced concrete structures exposed to aggressive chloride environment. The spatial variability of concrete cover ( c ), chloride diffusion coefficient ( D a 0 ) and other durability parameters are considered in the simulation, and the effect of batch-production of concrete is accounted for in the spatial variation modelling of c and D a 0 . Taking the Hong Kong-Zhuhai-Macau sea-link project as an example, the paper evaluates the durability performance of the immerged tube tunnel over the expected service life, and compares a range of durability design specifications with different target reliabilities and combinations of c and D a 0 , in terms of the probability & extent of surface damage. With three maintenance levels prescribed by surface damage grade at intervention, the paper compares the intervention time of different durability design specifications. The results provide a comparative tool to aid designers in selecting design specifications to achieve owner-concerned durability objective. [ABSTRACT FROM AUTHOR]

This paper investigates energy flow of Multi-Carrier Energy Systems using Point Estimate Method and Monte Carlo simulation considering uncertainties, which may happen in the Electrical, Natural Gas, and District Heating Networks all together. These uncertainties could occur from the probabilistic behavior of loads or unforeseen faults. An innovative probabilistic energy flow of Multi-Carrier Energy Systems based on Point Estimate Method has been presented in this paper. Results for two different case studies are investigated and compared against those achieved from the Monte Carlo simulation. The results prove that the presented point estimate schemes have precise results, smaller computational burden, and time, comparing than Monte Carlo simulation method. [ABSTRACT FROM AUTHOR]

The results of the research in the field of benzene, toluene, ethylbenzene and xylene isomers (BTEX) concentrations in exhaust gases of spark ignition engines under different operating conditions are presented in this paper. The aim of this paper is to gain a clearer insight into the impact of different engine working parameters on the concentrations of BTEX. The experimental investigation has been performed on the SCHENCK 230 W test stand with the controlled IC engine. The engine operating points have been chosen based on the results of a simulation and they are considered as the typical driving conditions according to the New European Driving Cycle. Concentration levels of BTEX compounds in exhaust gas mixtures have been determined by gas chromatography technique by using the combination of Supelcowax 10-Polyethylene glycol column and the PID detector. Based on the experimental research results, the emission model of BTEX compounds has been defined by the simulation of movement of a Fiat Punto Classic passenger car in accordance with the NEDC cycle. Using the results obtained within the simulation, the official statistics on the number of gasoline-powered cars on the territory of the Republic of Serbia and the European Commission data on the annual distance traveled by car, the amounts of BTEX compounds emitted annually per car have been estimated, as well as the emissions of the entire Serbian car fleet. [ABSTRACT FROM AUTHOR]