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This paper proposes a new method to improve re performance of intra-field interpolation which is the mos~ important element of deinterlacing method. Traditional edge- based methods were poor at determining accurate edge iirection which decides interpolation performance. The 7roposed method decides the direction and slope of edge based on locally adaptive-thresholded binary image to mprove efficiency and accuracy, and it also increased the ~orizontal size of search window to 15 for better direction ietermination at gentle slope. Compared to traditional edge- based methods, interpolation based on binary image, which is ,`enerated using the proposed method, leads to great erformance improvement. With computer simulations for a ~`ariety of images, this paper shows the new approach is much ~etter than traditional methods.. [ABSTRACT FROM AUTHOR]

This paper presents an implementation of an ~daptive beamformer in a hands-free unit. The proposec~ ~daptive beamformer suppresses stationary noise an~ nterference sound. The adaptive beamformer and acoustic `cho canceller were implemented in a compact hands-free mit with a low-cost DSP. Experimental results demonstrate he noise reduction performance of the hands-free unit'. [ABSTRACT FROM AUTHOR]

Simple moving average (SMA) is a well-known forecasting method. It is easy to understand and interpret and easy to use, but it does not have an appropriate length selection mechanism and does not have an underlying statistical model. In this paper, we show two statistical models underlying SMA and demonstrate that the automatic selection of the optimal length of the model can easily be done using this finding. We then evaluate the proposed model on a real data-set and compare its performance with other popular simple forecasting methods. We find that SMA performs better both in terms of point forecasts and prediction intervals in cases of normal and cumulative values. [ABSTRACT FROM AUTHOR]

This paper considers the influence of cross-diffusion on semi-arid ecosystems based on simplified Hardenberg's reaction diffusion model. In the square region, we analyze the properties of this model and give the relaxation time correspond to the system to prejudge the approximate time of this system stabilization process. The numerical results are constant with the theory very well. [ABSTRACT FROM AUTHOR]

In this paper, an application of the Picard's iterative method for finding the solution of two phase Stefan problem is presented. In the proposed method an iterative connection is formulated, which allows to determine the temperature distribution in considered domain. Another unknown function, describing position of the moving interface, is approximated with the aid of linear combination of some base functions. Coefficients of this combination are determined by minimizing a properly constructed functional. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm for checking and enforcing passivity of behavioral reduced-order macromodels of linear time-invariant systems, whose frequency-domain (scattering) responses depend on external parameters. Such models, which are typically extracted from sampled input–output responses obtained from numerical solution of first-principle physical models, usually expressed as partial differential equations, prove extremely useful in design flows since they allow optimization, what-if or sensitivity analyses, and design centering. Starting from an implicit parameterization of both poles and residues of the model, as resulting from well-known model identification schemes based on the generalized Sanathanan–Koerner iteration, we construct a parameter-dependent skew-Hamiltonian/Hamiltonian matrix pencil. The iterative extraction of purely imaginary eigenvalues of the pencil, combined with an adaptive sampling scheme in the parameter space, is able to identify all regions in the frequency-parameter plane where local passivity violations occur. Then, a singular value perturbation scheme is set up to iteratively correct the model coefficients, until all local passivity violations are eliminated. The final result is a corrected model, which is uniformly passive throughout the parameter range. Several numerical examples demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper attempts to quantify the effects of contaminants on electrical contact resistance. Based on an idealized model, simple and explicit scaling laws for the electrical contact resistance with dissimilar materials are constructed. The model assumes arbitrary resistivity ratios and aspect ratios in the current channels and their contact region, for both Cartesian and cylindrical geometries. The scaling laws have been favorably tested in several limits, and in sample calculations using a numerical simulation code. From the scaling laws and a survey of the huge parameter space, some general conclusions are drawn on the parametric dependence of the contact resistance on the geometry and on the electrical resistivity in different regions. [ABSTRACT FROM AUTHOR]

The paper presents the mathematical model and numerical example to simulate flow through the turbocharger of supercharged Diesel engine MB 836Db. The computer programe which use the Phoenics software procedures, personal subroutines and functions, permits to simulate the unsteady flow in case of the geometry considered. The paper presents some numerical results, as in 3D graphics. [ABSTRACT FROM AUTHOR]

In this paper, we present a parallel cloth simulation with an efficient collision detection algorithm for interactive AR applications. In the first step of the proposed method, a set of sphere colliders is automatically defined for the 3D moving object colliding with a cloth model for the effective collision detection even on low-end devices. In the second step, the collision detection and handling between a set of sphere colliders and a cloth model are performed in parallel. We propose an efficient collision handling method based on a sphere to prevent the penetration of cloth into the object which can be happened due to the low mesh resolution of the cloth model. The proposed method was implemented as a plugin for Unity which is widely used for the real-time game development. Comparative experimental tests with the cloth object basically provided by Unity was performed in order to analyze the performance of the proposed method. As a result, we confirmed that the proposed method can reduce the cumbersome work to manually build colliders on a 3D model, and can effectively express more accurate and plausible behavior of the cloth that collides with the object. [ABSTRACT FROM AUTHOR]

This paper suggests an estimation method for ship's hydrodynamic coefficients, which is based on the system identification method that calculates an optimum value in a mathematical way. For the purpose of modelling existing ships, this study collects real ship sea trial data as benchmarks. Prior to the optimization, a sensitivity analysis is carried out for easy and effective optimization. The simulation results using optimized coefficients agree well with corresponding benchmarks. Following this, with various trim and draught conditions, this study suggests new estimation formulas that concern all trim and draught conditions. Simulation results applying the estimation formulas are satisfactory in regard to a corresponding benchmark, compared to a result obtained by using an existing regression formula. [ABSTRACT FROM AUTHOR]

This paper confronts the numerical simulation of steady flows of fluid layers through channels of varying bed and width. The fluid consists of two immiscible fluid layers with constant density, and it is assumed to be of a one-dimensional shallow flow. The governing equation is a coupled system of two-layer shallow water models. In this paper, we apply a direct extension of the momentum conserving scheme previously used for solving the one layer shallow water equations. Computations of various steady-state solutions are used to demonstrate the performance of the proposed numerical scheme. Under the influence of a given flow rate, the numerical steady interface is generated in a channel topography with a hump. The results obtained confirm the analytic steady interface of the two-layer rigid-lid model. Furthermore, the same scheme was used with an additional artificial damping to simulate the maximal exchange flow in channels of varying width. The numerical steady interface agreed well with the analytical steady solutions. [ABSTRACT FROM AUTHOR]

The optimizing design for enhancement of the micro performance of manipulator based on analytical models is investigated in this paper. By utilizing the established uncanonical linear homogeneous equations, the quasi-static analytical model of the micro-manipulator is built, and the theoretical calculation results are tested by FEA simulations. To provide a theoretical basis for a micro-manipulator being used in high-precision engineering applications, this paper investigates the modal property based on the analytical model. Based on the finite element method, with multipoint constraint equations, the model is built and the results have a good match with the simulation. The following parametric influences studied show that the influences of other objectives on one objective are complicated. Consequently, the multi-objective optimization by the derived analytical models is carried out to find out the optimal solutions of the manipulator. Besides the inner relationships among these design objectives during the optimization process are discussed. [ABSTRACT FROM AUTHOR]

This paper presents simulation methodology that combines a local nonmatching grid with a discrete fracture model. Designed for 2D and 3D multiphase flow simulations in standard simulators, the method handles matrix-matrix, fracture-fracture, and matrix-fracture connections in the context of an unstructured, local nonmatching grid. The grid is generated at the fracture intersections, enabling accurate modeling of small control volumes between connecting fractures. Grids are obtained simply by redistributing the volume of small control volumes surrounding the small control volumes, making the method computationally efficient. A unified method to calculate the interblock transmissibility is used for both matching and nonmatching mesh. An unstructured finite-volume graph-based reservoir simulator with a two-point flux approximation reads the new grid by making a simple modification to the graph of connections between the control volumes. The method requires no special treatment of fracture-fracture or matrix-fracture transmissibility calculations and has the flexibility to simulate any flow problem efficiently. Several 2D and 3D numerical examples demonstrate the method's performance and accuracy. Both simple and complex fracture configurations are presented with various levels of geologic and fluid complexity. The numerical results are in good agreement with those of a reference solution obtained on a finely structured grid. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to investigate the propulsive performance of the hollow rotating detonation engine (RDE) with a Laval nozzle. Three-dimensional simulations are carried out with a one-step Arrhenius chemistry model. The Laval nozzle is found to improve the propulsive performance of hollow RDE in all respects. The thrust and fuel-based specific impulse are increased up to 12.60 kN and 7484.40 s, respectively, from 6.46 kN and 6720.48 s. Meanwhile, the total mass flow rate increases from 3.63 kg/s to 6.68 kg/s. Overall, the Laval nozzle significantly improves the propulsive performance of the hollow RDE and makes it a promising model among detonation engines. [ABSTRACT FROM AUTHOR]

In this paper, on the basis of the micropolar (Cosserat) continua approach, a constitutive model for simulation of granular material (e.g., sand) response in the elastoplastic range has been presented. Numerical analyses on strain localization in this type of material are carried out in the last part of this paper. The influence of the evolution of the internal length-scale micropolar parameters on the formation of strain localization is investigated. [ABSTRACT FROM AUTHOR]

In this paper, we used a 3-D discrete-element model, Grains3D, which allows the simulation of unsteady granular flows of monodisperse soft spherical particles in a common situation (i.e., down a rectangular channel). A series of numerical dam-break experiments was performed to predict the behavior of granular columns that propagate down a rough horizontal surface from different initial conditions (varying the initial aspect ratio). Numerical results were compared to those obtained experimentally by Lajeunesse et al. (Phys Fluids 17:103302, ) from a similar configuration. Runout distance, temporal flow evolution, deposit morphology and internal flow structures of similar laboratory experiments were quantitatively reproduced as well as prediction of empirical and theoretical scaling laws. This paper highlights that such fully 3-D simulations of soft-spheres can remarkably capture dam-break collapses performed in a rectangular channel. Moreover, Grains3D can provide a complete physical description of such complex unsteady systems which will be the topic of future on-going studies. [ABSTRACT FROM AUTHOR]

This paper presents a composite programmable graph grammar model of the three dimensional self-adaptive hp Finite Element Method (hp-FEM) algorithms. The computational mesh composed of hexahedral finite elements is represented by a composite graph. The operations performed over the mesh are expressed by composite graph grammar productions. The three dimensional model is based on the extension of the two dimensional model for rectangular finite elements. This paper is concluded with numerical examples, presenting the generation of the optimal mesh for simulation of the Step-and-Flash Imprint Lithography (SFIL), the modern patterning process. [ABSTRACT FROM AUTHOR]

Fluid bulk modulus is a fluid property that has been studied extensively over the past years. The numerical value of this property depends on the operating conditions, the amount of entrained air, and the way compression is applied and to some extent, the mathematical form it is defined. However, some confusion over what is the most appropriate value to use in simulation and design studies exists. Many significant studies on experimental techniques to measure this property have been proposed but in some instances the actual operating conditions are not well defined or assume a form which may not be consistent with the actual operating conditions. The objective of this paper is to first define some of the more common definitions of bulk modulus and then present a summary of the literature that is based on fluid bulk modulus. Where appropriate, some comments on some of the confusion over definitions will be expanded upon. The pressure and temperature range over which these bulk modulus measurements can be made is dependent on the design of the test apparatus. But generally the pressure range is from the atmospheric pressure to 690 MPa and the temperature range is from - 40 to 270 °C. A companion paper will present a comparison of some of the models that have come out of this literature review. [ABSTRACT FROM AUTHOR]

In this paper, we consider a generalized fast marching method (GFMM) as a numerical method to compute dislocation dynamics. The dynamics of a dislocation hypersurface in ℝN (with N = 2 for physical applications) is given by its normal velocity which is a nonlocal function of the whole shape of the hypersurface itself. For this dynamics, we show a convergence result of the (IFMM as the mesh size goes to zero. We also provide some numerical simulations in dimension N=2. [ABSTRACT FROM AUTHOR]

This paper proposes a new approach for solving generation scheduling and ramp rate constrained unit commitment (GSRCUC) considering spinning reserve uncertainty. In order to handle reserve uncertainty the estimated probability that spinning reserve might be called and delivered is taken into account. A combinatorial genetic algorithm and lambda iteration method is applied to solve such problem. The proposed methodology is implemented to a 10-unit base problem and a 26-unit IEEE reliability test system. The performance of GSRCU model associated with the impact of spinning reserve requirement (SRR) probability is studied in this paper. Numerical results show a significant improvement in the solutions of a cost-based unit commitment in comparison with the other studies. [ABSTRACT FROM AUTHOR]

This paper begins with presenting a mathematical model for contaminant transport in the fractured vuggy porous media of a species of contaminant (PCP). Two phases are numerically simulated for a process of contaminant and clean water infiltrated in the fractured vuggy porous media by coupling mixed finite element (MFE) method and finite volume method (FVM), both of which are locally conservative, to approximate the model. A hybrid mixed finite element (HMFE) method is applied to approximate the velocity field for the model. The convection and diffusion terms are approached by FVM and the standard MFE, respectively. The pressure distribution and temporary evolution of the concentration profiles are obtained for two phases. The average effluent concentration on the outflow boundary is obtained at different time and shows some different features from the matrix porous media. The temporal multiscale phenomena of the effluent concentration on the outlet are observed. The results show how the different distribution of the vugs and the fractures impacts on the contaminant transport and the effluent concentration on the outlet. This paper sheds light on certain features of karstic groundwater are obtained. [ABSTRACT FROM AUTHOR]

In this paper, a demonstrative technological implementation of a shipboard 2.15-MVA generation system is described, along with its modeling, numeric simulation, and some factory tests. The system, named Naval Package (NP), is part of a demonstrative program commissioned by Italian Navy for preliminary evaluations of medium-voltage dc supply technologies aimed at equipping its future vessels. The NP is made by a dual-star alternator, whose two stator three-phase windings feed two full-bridge diode rectifiers, respectively. The alternator (rated speed 6300 r/min) is designed to be moved by a 22 000-r/min gas turbine through a gearbox. This paper will present NP innovative issues, with reference to design solutions, operative requirements, dynamic modeling under normal and faulty conditions, and some factory tests. [ABSTRACT FROM AUTHOR]

This paper presents the control system based on the so-called repetitive control for a five-level flying-capacitor dynamic voltage restorer (DVR). This DVR multilevel topology is suitable for medium-voltage applications and operated by the control scheme developed in this paper. It is able to mitigate power-quality disturbances, such as voltage sags, harmonic voltages, and voltage imbalances simultaneously within a bandwidth. The control structure has been divided into three subsystems; the first one improves the transient response of the filter used to eliminate the modulation high-frequency harmonics, the second one deals with the load voltage; and the third is charged with maintaining balanced voltages in the flying capacitors. The well-developed graphical facilities available in PSCADIEMTDC are used to carry out all modelling aspects of the repetitive controller and test system. Simulation results show that the control approach performs very effectively and yields excellent voltage regulation. [ABSTRACT FROM AUTHOR]

This paper presents a scheme to reduce the on-die voltage noise that occurs due a buffer switching event. Both output and input buffer switch events are addressed. A generic power delivery network (PDN) model with parasitic inductance is assumed. A change in current (di/dt) across the inductor is considered the primary cause of the voltage noise. On-die decoupling capacitance is traditionally added to the power delivery network to address this problem and to limit the droop. The method described in the paper shows a principally different approach. The maximum di/dt is managed to reduce the voltage noise. It is proposed to send to a buffer a current waveform from an external supply or to recycle charge from a locally charged capacitance when the di/dt occurs, thus substantially reducing the on-die voltage noise. Alternatively, at a given acceptable level of voltage noise the on-die capacitance can be reduced, providing significantly lower product cost. This paper provides theoretical and modeling background of the pro. posed schemes and includes simulation results on several performance characteristics. [ABSTRACT FROM AUTHOR]

To meet the requirement of exploring a new generation of CNC systems based on STEP-NC, NURBS interpolation has been studied. In contrast to existing NURBS interpolation based on the Taylor’s expansion, this paper proposes a new method for NURBS interpolation which is based on exponential smoothing forecasting. The new method is very simple; it decreases the computational load observably, and speed and precision control are also achieved. This paper presents relative formulas and main computational processes, including speed and precision control, computation of real-time mapping, computation of real-time track, etc. The simulation results indicate that the method is feasible and has high-precision and better real-time performance, which is sufficient for the STEP-NC system. [ABSTRACT FROM AUTHOR]

The response of a structure to medium-frequency vibrations is highly dependent on several phenomena. One of these, the behavior of joints between substructures, is essential because it controls the distribution of the power injected into the structure and governs most of the dissipative effects. This paper introduces a new method for the identification of joint parameters from experimental vibration data, inspired by previous works on finite element model updating using the error in the constitutive relation. Since such numerical techniques are not suitable for the medium-frequency range, in which the finite element mesh must be refined, our work uses the numerical framework of the variational theory of complex rays, which is a Trefftz approach entirely dedicated to the calculation of medium-frequency vibrations at very low cost. The main scope of this paper is the presentation of the formulation and its validation against actual and numerically-simulated experimental results. [ABSTRACT FROM AUTHOR]

In a simulation-based planning and control framework, timely monitoring, analysis, and control is important not to disrupt a dynamically changing system. To meet this temporal requirement, a dynamic-data-driven adaptive multi-scale simulation (DDDAMS) paradigm was proposed earlier, where the fidelity of a complex simulation model adapts to available computational resources by incorporating dynamic data into the executing model, which then steers the measurement process for selective data update. In this work, a sequential Monte Carlo method (sequential Bayesian inference technique) is proposed and embedded into the simulation to enable its ideal fidelity selection given massive datasets under the DDDAMS framework. As dynamic information becomes available, the proposed method makes efficient inferences to determine the sources of abnormality in the system (a shop floor in this paper). A parallelisation framework is also discussed to further reduce the number of data accesses while maintaining the accuracy of parameter estimates. A prototype DDDAMS involving the proposed algorithm has been implemented successfully for preventive maintenance scheduling and part routing scheduling in a semiconductor manufacturing supply chain, reducing the average waiting time of batches and increasing the machine utilisation significantly. [ABSTRACT FROM AUTHOR]

In a companion paper, experimental evidence was elaborated to confirm that in particular circumstances the performance of level-furrow irrigation can exceed that of level-basin irrigation. The application of a single furrow simulation model to an irrigation event in a level-furrow field resulted in large estimation errors. To overcome them, the development and validation of a numerical model of level-furrow irrigation is reported in this work. The model is based on the interconnection of a number of one-dimensional channels. The individual channels are connected using confluence or bifurcation points. Furrow infiltration is modelled through a Kostiakov infiltration equation including the furrow discharge as an independent variable. The proposed model is validated using the experimental level furrow evaluation presented in the companion paper. Finally, the model is applied to explore the conditions in which level furrow irrigation can outperform level basin irrigation. The proposed model stands as a valuable tool in the design and management of level furrow irrigation systems. [ABSTRACT FROM AUTHOR]

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Numerical models for vibro-acoustic analyses of complex mechanical systems are becoming more and more popular, in particular in the field of virtual product development. Therefore, reliable, comprehensive, and validated modeling methodologies remain crucial. However, system characteristics such as elasticities of the drive train components and nonlinear characteristics can lead to complex, and costly numerical models with a huge number of degrees of freedom. This may raise not only the need for novel and reasonable modeling strategies, but also exacerbates validation process, due to the wide scope in terms of operating conditions. In practice, structure-borne noise signals, for example, from accelerometers, are often used for the validation of mechanical systems. By choice of a sufficient number of measurement points, the interpretation becomes more complex. A lot of vibration response curves then need to be compared and interpreted over a wide operating range. In general, the interpretation focuses on deviations in quality and quantity. In this paper, to overcome these mentioned challenges, a validation methodology is proposed allowing a fast and transparent check of a number of captured signals. Therefore, it is shown how the original information can be reduced in a meaningful manner, making it possible to run a fast and accurate validation. The method is demonstrated on a real application with high mechanical complexity and it is shown that the chosen parameters are reliable. [ABSTRACT FROM AUTHOR]

Measurement data obtained from Weigh-in-Motion systems support protection of road pavements from the adverse phenomenon of vehicle overloading. For this protection to be effective, WIM systems must be accurate and obtain a certificate of metrological legalization. Unfortunately there is no legal standard for accuracy assessment of Weigh-in-Motion (WIM) systems. Due to the international range of road transport, it is necessary to standardize methods and criteria applied for assessing such systems' accuracy. In our paper we present two methods of determining accuracy of WIM systems. Both are based on the population of weighing errors determined experimentally during system testing. The first method is called a reliability characteristic and was developed by the authors. The second method is based on determining boundaries of the tolerance interval for weighing errors. Properties of both methods were assessed on the basis of simulation studies as well as experimental results obtained from a 16-sensor WIM system. [ABSTRACT FROM AUTHOR]

This paper gives a detailed description of an algorithm for the solution of a specialized Linear Programming model, to be called the Machine Loading model. It is a generalization of the Transportation Problem, in that weighting factors are applied to the individual elements which form the row and column sums. For the Machine Loading model, the simplex method reduces to a specialized algorithm which generalizes the stepping stone method of the Transportation Problem [2], [3]. With the resulting generalized stepping stone method, it becomes practicable to solve many large-scale problems for which the direct application of the simplex method would be impracticable. The present paper is restricted to a discussion of the following topics: (I) the general characteristics of the model and its topological features; (ii) a detailed solution algorithm, including a consideration of degenerate cases and the use of a computer; (iii) a more restrictive capacitated model and the corresponding modifications to the solution algorithm; and (iv) the complete illustrative solution of a numerical example. The purpose is to aid interested readers in gaining familiarity with the algorithm and facility in the solution of numerical problems. No derivations or proofs will be included. [ABSTRACT FROM AUTHOR]

This paper investigates the increase in the response speed and stability of artificial intelligence systems that control dynamic technical objects. The problem of calculating the optimal time of switching an artificial intelligence system between software classes by the criterion of the rigidity degree of the model of a control object is considered. The solution of this problem is proposed for the general case of the control object dynamics when the rigidity of the mathematical model can significantly change during functioning and it is necessary to dynamically determine the moment of transition from standard methods of numerical integration to specialized numerical methods intended for calculating rigid dynamic models. [ABSTRACT FROM AUTHOR]

Determination of forces acting on planing hulls in maneuvering has been turned into an interesting problem during the last decade. Different methods, based on mathematical or empirical approaches, are elicited to compute hydrodynamic forces and moments acting on the boat in different simplified conditions, such as steady yawed or heeled conditions. Modeling of different conditions and combining them with each other may lead to initiate a final simulation model for 6DOF motion of planing boats in calm water. These simple modeling approaches, in other words, can be considered as basics of a final 6DOF model. The current article address hydrodynamic modeling of yawed motion for hard-chine planing boats in calm water. The current research paper is primarily focused on the determination of horizontal force and yaw moment acting on the boat as it moves forward in a steady yawed condition. The derivation approach is based on mathematical formulation of 2D1T theory and added mass variation in longitudinal direction. Virtual mass of a wedge in horizontal direction is analytically found and then the final force and moments are computed using extension of sectional forces, acted on wedge section of the boat, over entire wetted length of the vessel. The precision of the proposed model is verified by comparing the computational values against previous experimental data. An improvement for the model has been considered to conquer some of the drawbacks reported by previous researchers. The comparison exhibits an improvement of the model; the increase in added mass which was previously discussed by previous researchers can be seen. Also, it is observed that in the case that the wetted length of the boat is small, the transom reduction works well and leads to an accurate prediction of sway force. Finally, it is viewed that the computed yaw moments are in a fair agreement with previous experimental data. [ABSTRACT FROM AUTHOR]

This paper proposes a varying-coefficient single-index measurement error model, which consists of measurement error in the index covariates. We combine the simulation-extrapolation technique, the local linear regression and the weighted least-squares method to estimate the unknowns of the current model, and develop the asymptotic properties of the resulting estimators under some conditions. A simulation study is conducted to evaluate the proposed methodology, and a real example is also studied to illustrate our given methodology. [ABSTRACT FROM AUTHOR]

The engineering translation of the aquatic animal propulsion systems and its appropriate application to marine vehicles help them to achieve movement with less power and hence resulting in the CO2 emission reduction. In this paper, the design of a robotic fish with pectoral and caudal fins, which operates at subsurface, is considered. The robofish body shape and fin geometrical parameters are also important with regard to the resistance and power aspects. Numerical studies are conducted with the robotic fish to determine its resistance in the bare hull and also for the case fitted with fins. Experimental studies carried out on a remotely operated surface ship with thunniform mode of fish propulsion, which operates at subsurface, are considered. Model tests are performed to analyse the propulsive performance of fishtail propulsion for the remotely operated surface ship in bollard pull condition and in self-propulsion mode. [ABSTRACT FROM AUTHOR]

Lane changing is one of the most common maneuvers on motorways. Although macroscopic traffic models are well known for their suitability to describe fast moving crowded traffic, most of these models are generally developed in a one-dimensional framework; henceforth lane-changing behavior is either not explicitly modeled or is explicitly forbidden. In this paper, we propose a macroscopic model which accounts for lane-changing behavior on motorways, based on a two-dimensional extension of the Aw and Rascle [SIAM J. Appl. Math., 60 (2000), pp. 916-938] and Zhang [Transport. Res. B-Meth., 36 (2002), pp. 275-290] macroscopic model for traffic flow. Under conditions when lane-changing maneuvers are no longer possible, the model"relaxes" to the onedimensional Aw-Rascle-Zhang model. Following the same approach as in [SIAM J. Appl. Math., 63 (2002), pp. 259-278], we derive the two-dimensional macroscopic model through scaling of time discretization of a microscopic follow-the-leader model with driving direction. We provide a detailed analysis of the space-time discretization of the proposed macroscopic model as well as an approximation of the solution to the associated Riemann problem. Furthermore, we illustrate some promising features of the proposed model through some numerical experiments. [ABSTRACT FROM AUTHOR]

Generalizations of the point-optimal panel unit root tests of Moon, Perron and Phillips (MPP) are developed to cover cases of serially correlated errors. The resulting statistics involve two modifications relative to those of MPP: (a) the error variance is replaced by the long-run variance; (b) centring of the statistic is adjusted to correct for second-order bias effects induced by the correlation between the error and lagged dependent variable. [ABSTRACT FROM AUTHOR]