Search

To enhance the quality and efficiency of computer-enabled generation of papers for Test for English Majors Band 8 (TEM-8), a paper generation model supported by sparrow search algorithm-genetic algorithm was studied. First, a simplified test paper generation mathematical model was set up after analyzing and studying types and characteristics of TEM-8 tasks. In the model, quantity, type, difficulty, discrimination degree, scores, exposure, and answering time of test questions were taken into consideration. To enhance the optimizing effect of the genetic algorithm for searching test questions, the traditional genetic algorithm was improved by introducing the sparrow search algorithm into the model to achieve a better crossover rate, variance rate, optimization precision, and speed of the genetic algorithm. A new sparrow search-genetic algorithm (SSA-GA) was designed, and the optimizing effect of SSA-GA was verified to be ideal through optimizing six standard test functions. Then, SSA-GA was applied to conduct experimentation with test paper generation, and comparison with traditional genetic algorithms was also made. The values of best and average fitness of SSA-GA were better than those of the traditional genetic algorithm (GA) in the paper generation. Exposure rate and success rate in TEM-8 paper generation of SSA-GA were higher than those of traditional GA in TEM-8 paper generation. Results showed that the studied SSA-GA could implement test paper generation with higher speed and better quality. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study is to model and to simulate the thermal and electrical efficiencies of the cogeneration plant of a paper mill. The final purpose is the benefits optimization by adjusting production to the amount of energy to be sold. It is necessary to know it because the sale price goes down when the actual production of electrical energy does not match the scheduled power. [Copyright &y& Elsevier]

The influence of nonuniform aging has not been considered in the prediction of the frequency domain spectroscopy (FDS) of the transformer oil-paper insulation (OPI) when using the finite element method (FEM). Given this issue, the modified simulation model was constructed based on the XY model and FEM. In the current work, the dielectric response property of the pressboards with different aging conditions in the modified model was characterized by its dielectric response parameters measured in the lab. Then the modified simulation model constructed in a 3-D system would be applied to study the effect of both nonuniform aging and the axial geometry on the FDS of OPI. Finally, the feasibility of the proposed models was verified by comparing the measured FDS and the predicted FDS. This article is expected to provide a model for predicting the FDS of the transformer OPI including the effect of nonuniform aging. [ABSTRACT FROM AUTHOR]

Abstract: Through sampling reed in Shuangtai estuary wetland in April, 2009 and simulation test in Shenyang Agricultural University, we analyze the removal efficiency of Cu, Zn, Pb and Cd during different growth period of reed and distribution of them in various parts of reed. The results show that the removal efficiency is best in jointing stage, the removal of Pb largest with 21% increase and 30% in sprout and exhibition leaf period, the removal of Zn largest with 53% and 29% increase in jointing stage and the maturity period, the removal of Cd largest with 40% increase in the different growing season. The absorption amount of Cu, Zn, Pb and Cd in roots of reed reaches maximum during the growth, followed by in stems and in leaves. Absorptive capacity in the whole plant for Cu, Zn, Pb and Cd exists extremely significant difference (p <0.01). The order is Pb>Zn>Cu>Cd. The absorption in root is higher than in stems and in leaves (p <0.05), but Zn and Cd absorption amount has no significant differences in stems and leaves (p >0.05). [Copyright &y& Elsevier]

Drying of a coated paper is modeled and simulated. The paper sheet is assumed to form three zones, and each zone has its own drying mechanism. Coupling of energy and mass balances must be used in order to solve differential equations. The simulations are carried out in various drying conditions i.e., only hot air drying, only radiant drying, and mixed hot air-radiant drying. Also the effect of one side and two side assumption on evaporation is studied. Effect of venting air speed and radiant heat source presence and its distance from the drying surface on the drying of a coated paper has been studied. It is found that both distance and venting air speed are inversely related to drying in mixed hot air-radiant drying. Both surfaces participate in evaporation however, during the last time of drying, no difference between the upper and the bottom surfaces exist. [ABSTRACT FROM AUTHOR]

Quantifying the impact of a scholarly paper is of great significance, yet the effect of geographical distance of cited papers has not been explored. In this paper, we examine 30,596 papers published in Physical Review C, and identify the relationship between citations and geographical distances between author affiliations. Subsequently, a relative citation weight is applied to assess the impact of a scholarly paper. A higher-order weighted quantum PageRank algorithm is also developed to address the behavior of multiple step citation flow. Capturing the citation dynamics with higher-order dependencies reveals the actual impact of papers, including necessary self-citations that are sometimes excluded in prior studies. Quantum PageRank is utilized in this paper to help differentiating nodes whose PageRank values are identical. [ABSTRACT FROM AUTHOR]

In this paper, polysiloxane is used to modify insulation paper cellulose, and molecular dynamics methods are used to evaluate the glass transition temperature and mechanical properties of the paper before and after the modification. Analysis of the static mechanical performance of the model shows that, with increasing temperature, the elastic modulus of both the modified and unmodified cellulose models decreases gradually. However, the elastic modulus of the modified model is greater than that of the unmodified model. Using the specific volume method and calculation of the mean square displacement of the models, the glass transition temperature of the modified cellulose model is found to be 48 K higher than that of the unmodified model. Finally, the changes in the mechanical properties and glass transition temperature of the model are analyzed by energy and free volume theory. The glass transition temperatures of the unmodified and modified cellulose models are approximately 400 K and 450 K, respectively. These results are consistent with the conclusions obtained from the specific volume method and the calculation of the mean square displacement. It can be concluded that the modification of insulation paper cellulose with polysiloxane will effectively improve its thermal stability. [ABSTRACT FROM AUTHOR]

In recent years the print industry has been facing constant and increasing competition from the double onslaught of the Internet and the proliferation of television channels. In order to survive as a viable industry, print enterprises must streamline and exploit up-to-date economizing measures. A key cost element in the print industry is paper, representing between 20% and 30% of total printing expenditures. Thus, any improvement in the operational efficiency of paper reel management has the potential of yielding considerable cost savings. It is in this context that we analyze the effect of enhancing the available paper reel supply chain information through the use of semi passive Radio Frequency IDentification (RFID) technology. Focusing on the printing house, we develop both simulation models and formulas that forecast savings from having better information. Thereafter we implemented the system and compared the forecasts to actual savings. Using standard economic evaluation techniques we unequivocally show the economic imperative of introducing semi passive RFID technology. Even though this study was carried out in a specific printing house, we argue that its implications are far wider, affecting other industries. [ABSTRACT FROM AUTHOR]

In this paper, we propose the model of ink fixing on paper with watermarks: properties of positive watermark areas are similar to high-calender paper and properties of areas beyond positive watermark and areas of negative watermark are similar to paper of machine smoothness. It causes difference of ink pigment and binding agent penetration into paper. Colorimetric evaluation of the difference between area of positive watermark and beyond it for offset printed paper with watermark shows the essential distinction: the value of colour shift ΔE* is 6,5-20,0 and it depends on ink thickness. The technique of preparing paper cross sections is developed relying on microtome cuts. The light microscopic study of paper cross sections demonstrate a big difference of ink penetration depth in zone of positive watermark (9-16 μm) and beyond this zone (22-40 μm). Therefore, through experiments conducted by employing colorimetry as well as microscopic study of printed paper with watermarks cross sections, we prove the feasibility of the proposed model. [ABSTRACT FROM AUTHOR]

Understanding the effects of water absorption on the geometry of a paper sheet is important for inkjet printing applications, since internal moisture content differences may cause unacceptable out-of-plane deformations. The present work focuses on moisture-induced deformations due to a moisture content that is uniform over the thickness of the sheet. Large enough in-plane differences will cause the sheet to buckle, leading to a wavy pattern at the edges of the sheet. Two approaches are utilized to study this for levels of moisture content up to and including the threshold for buckling. An analytical approach, based on geometrically nonlinear plate theory (von Kármán theory), and a numerical one, using commercially available finite element software, are presented. As a first reference problem an isotropic circular plate, wetted uniformly at its center, is solved both analytically and numerically for the in-plane stress distribution, the buckling threshold, and the resulting buckling mode. Secondly, the same is done for an orthotropic rectangular plate, wetted at its edges. Here, in the analytical approach a Rayleigh–Ritz analysis is employed to approximate the buckling threshold. The latter is also calculated by numerical means. The results show that the methods provide results consistent with each other. [ABSTRACT FROM AUTHOR]

Much literature exists for rock-paper-scissors (RPS) game. It is well known in a single habitat that spatial models are more stable than well-mixed population. However, the mechanism of spatial stabilization has been unclear. In the present article, we study multilayer model of RPS game in a patchy environment; respective patches are set as lattices. The predation probability of one of three species is assumed to be reduced as a parameter. Simulations on two-layer system reveal the opposite result to those on a single-habitat system. Namely, the well-mixed population becomes stable. In contrast, extinction occurs by random migration in spatially-explicit model, when the reduced predation probability is below a certain critical value. The extinction in spatial model is found to be caused by the collapse of a kind of swarm intelligence (SI). In RPS system, large swarms of each species are automatically protected from its predator. Such a self-organized protection is one of the simplest examples of SI. We also discuss some serious problems for random migration. • Spatial pattern of rock, paper and scissors are studied in patchy environment. • A distinct point of the present paper is to set lattices as respective patches. • We illustrate that biodiversity is sustained by a kind of "swarm intelligence". • Large swarms of each species are automatically protected from its predator. [ABSTRACT FROM AUTHOR]

Copyright of Technical Journal / Tehnički Glasnik is the property of Polytechnic of Varazdin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposed a simulation method for the charge transport in single-layer oil-paper insulation. The method of transient upstream finite-element method (FEM) is derived in order to calculate the time variation of charge densities in medium. The numerical simulation of charge transport in the single-layer oil-paper insulation is realized by applying the transient upstream FEM to the transport equations of bipolar charges. With reasonable microparameter, the charge transport in an experimental object is simulated. The simulation results are consistent with the experimental data. A bent model of oil-paper insulation is analyzed to study the charge distribution under the actual condition. This paper provides an exploratory research to the simulation of charge phenomenon in oil-paper, and has guiding significance to the design of oil-paper insulation. [ABSTRACT FROM AUTHOR]

In this research, a security paper based on frequency selective structure technologies was designed and fabricated using selective wave reflection characteristics to prevent the offline leakage of confidential documents. Document leakage detection systems using security papers detect security papers using transceiving antenna gates. For the application of such systems, the structure must be designed with excellent reflection performance and stability at the angle of incidence. For this purpose, a loop and patch-type frequency selective structure based on a four-legged element structure was designed to have X-band frequency reflection characteristics. This design was based on optimized variables and was realized through the screen printing method using silver ink on A4 paper. It was verified that both the design and simulation results matched well. To verify its actual applicability, a detector module operable at 10 GHz was manufactured to observe both the security paper detection range in relation to distance with a signal strength of −10 dBm and the detection area in relation to the number of times that the security paper had been folded. [ABSTRACT FROM AUTHOR]

Abstract: A wide range of mathematical models for multiple effect evaporators in process industry including paper industry are well reported in the literature but not so extensive work on the dynamic behavior of MEE system is available in the literature. In the present study dynamic behavior of multi-effect evaporator system of a paper industry is obtained by disturbing the feed flow rate, feed concentration, live steam temperature and feed temperature. For this purpose an unsteady-state model for the multi-effect evaporator system is developed. Each effect in the process is represented by a number of variables which are related by the energy and material balance equations for the feed, product and vapor flow. A generalized mathematical model which could be applied to any number of effects and all kinds of feeding arrangements like forward feed, backward feed, mixed feed and spilt feed in the MEE system with simple modifications was finally obtained. Finally model for mixed feed sextuple effect falling film evaporators system was solved using MATLAB. For the steady state and dynamic simulation the ‘fsolve’ and ‘ode45’ solvers in MATLAB source code is used respectively. [Copyright &y& Elsevier]

The characterization and modeling of the out-of-plane behavior of fiber-based materials is essential for understanding their mechanical properties and improving their performance in various applications, especially in the forming process. Despite this, research on paper and paperboard has mainly focused on its in-plane behavior rather than its out-of-plane behavior. However, for accurate material characterization and modeling, it is critical to consider the out-of-plane behavior. In particular, delamination occurs during forming processes such as creasing, folding, and deep drawing. In this study, three material models for paperboard are presented: a single all-material continuum model and two composite models using different cohesion methods. The two composite models decouple in-plane and out-of-plane behavior and consist of continuum models describing the behavior of individual layers and cohesive interface models connecting the layers. Material characterization experiments are performed to derive the model parameters and verify the models. The models are validated using three-point bending and bulge tests and show good agreement. A case study is also conducted on the application of the three models in the simulation of a deep drawing process with respect to wrinkle formation. By comparing the simulation results of wrinkle formation in the deep drawing process, the composite models, especially the cohesive interface composite model, show greater accuracy in replicating the experimental results, indicating that a single continuum model can also be used to represent wrinkles. [ABSTRACT FROM AUTHOR]

Aim of this study was to simulate the water sensitive paper (WSP) behavior for estimate the unitary spray deposition on the target at varying spray features and target coverage. WSP images were produced assuming some simplifying hypotheses: spherical drops and circular stains randomly placed on the images. Sprays were described in terms of probability distribution function (PDF) of drop size (log-normal and Rosin-Rammler), coefficient of variation of diameters (CV), arithmetic mean diameter (AMD), and volume median diameter (VMD). The results from the simulations showed that the overlap between stains was independent of spray features: when the percentage of covered surface of WSP images ranged from 4.7% up to 61.6%, the overlap between stains ranged from 0.3% up to 33.4%. On the contrary, unitary deposit (volume per square centimeter, L\cm2) and particle density (number of distinct partice per square centimeter, particles/cm2) could be obtained from the percentage of covered surface if CV, AMD, VMD and PDF were known. However, assuming as spray parameter the VMD, the drop size distribution had almost no effect on the unitary deposit: with the same percentage of covered surface, the Rosin-Rammler PDF provided an estimate of the unitary deposit higher than log-normal distribution between 5% and 7% only. [ABSTRACT FROM AUTHOR]

We consider a two-dimensional model of three species in rock-paper-scissors competition and study the self-organisation of the population into fascinating spiraling patterns. Within our individual-based metapopulation formulation, the population composition changes due to cyclic dominance (dominance-removal and dominance-replacement), mutations, and pair-exchange of neighboring individuals. Here, we study the influence of mobility on the emerging patterns and investigate when the pair-exchange rate is responsible for spiral waves to become elusive in stochastic lattice simulations. In particular, we show that the spiral waves predicted by the system's deterministic partial equations are found in lattice simulations only within a finite range of the mobility rate. We also report that in the absence of mutations and dominance-replacement, the resulting spiraling patterns are subject to convective instability and far-field breakup at low mobility rate. Possible applications of these resolution and far-field breakup phenomena are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Capillary pressures in a carbon paper gas diffusion layer (GDL) having hydrophilic and hydrophobic pores of a polymer electrolyte membrane fuel cell (PEMFC) are investigated by both lattice Boltzmann simulations and experimental measurements. The simulated and measured capillary pressures as a function of water saturation for water drainage and imbibition processes in the GDL are presented and compared. It is shown that the pore-scale simulated drainage and imbibition capillary pressure curves are in good agreement with that obtained by experiment, both indicating the coexistence of hydrophilic and hydrophobic properties in the polytetrafluoroethylene (PTFE) treated carbon paper GDLs. The fitted capillary pressure curves, obtained from this paper, can provide more accurate predictions of the capillary pressure in carbon paper GDLs with non-uniform porosity and wettability than the standard Leverett–Udell relationship which was obtained for soil with more uniform porosity and wettability. [Copyright &y& Elsevier]

The article presents information on various papers discussed at the conference title "The Conference on Empirical Research in Accounting." The author states that scholar Carl Nelson made an attempt to link all research to empiricism and explains that all research had to have an empirical base. He says that Nelson found that the proper order is not that all research has to be empirical but rather that research has to be tested. The article states that it has become a well-known precept in science that one can not ever prove anything by observation.

Abstract: This study investigated the effects of bending curvature of simulated e-paper displays (−10cm, plane and 10cm) and ambient illuminance (50, 500, 6000 and 12,000lx) on the visual performance of young and elderly users for simulated electronic-paper displays. In total, 24 people comprising 12 young and 12 elderly users participated in this study. Young users demonstrated significantly enhanced visual performance using the simulated electrophoretic ink (E ink) e-paper display with ambient illuminance set at 50 and 500lx; however, participants did not demonstrate significantly different visual performance using the 2 simulated e-paper displays with ambient illuminance set at 6000 and 12,000lx. The bending curvature did not exhibit significant effects on the visual performance of young participants under various ambient illuminances. The elderly participants exhibited significantly enhanced visual performance using the simulated E ink e-paper display only when ambient illuminance was set at 50lx; however, participants did not exhibit significantly different visual performance using the two simulated e-paper displays with ambient illuminance set at other levels. Elderly users exhibited significantly enhanced visual performance when the bending curvature was set at 10cm, with ambient illuminance set at 50lx. Elderly users also demonstrated significantly enhanced visual performance under bending curvature settings of 10cm and plane, with ambient illuminance set at 500lx. However, the bending curvature of the simulated e-paper did not exhibit significant effects on the visual performance of elderly participants under ambient illuminance settings of 6000 and 12,000lx. [Copyright &y& Elsevier]

The Paper River is a classroom simulation designed to examine a negative externality generated by a productive process that elicits a Coasian solution. Previous experiments designed by Hazlett (1995), Nugent (1993, 1997), and Bergstrom and Miller (1997, 179–99) focus on how pollution emission rights can be efficiently allocated by the market through property rights. Although these experiments touch on property rights in demonstrating how emission rights are a more efficient means of reducing pollution than government imposed limits, they do not address Coase's Theorem directly. Classroom experiments that demonstrate Coase's Theorem include those by Delemeester and Neral (1995, 115–19) and Stodder (1996). In these activities, students imagine they are either the creator or recipient of a hypothetical externality. Although this approach is useful for conveying Coase's Theorem, it does not give students the opportunity to generate and experience the externality directly. In the Paper River, students create and experience an externality first hand and then conceptualize a correction procedure that is consistent with Coase's Theorem. The unique nature of this simulation allows students to be involved directly in the externality. In addition, it simulates an actual environmental problem, which will enable students to identify more easily other examples of externalities that affect our society, such as endangered species, destruction of the rainforests, and preservation of natural habitats. [ABSTRACT FROM AUTHOR]

We describe a method for characterization of the microstructure of a paper, in terms of the statistical distribution of the effective radii and lengths of the channels between the paper''s fibers, and the average coordination numbers that characterize the connectivity of such channels, both in the main planes of the paper and in the transverse direction perpendicular to these planes. The microstructure of the paper is then represented by a three-dimensional network of interconnected flow channels between the fibers. The geometrical characteristics of the channels, such as their effective radii and lengths, are selected from the statistical distributions obtained by the characterization method, as are the two average coordination numbers. Extensive computer simulations are carried out to compute the effective permeability tensor of the paper, and to investigate the effect of the various microstructural parameters on the tensor. These simulations indicate that the two average coordination numbers, as well as the spatial distribution of the fibers and their length, strongly influence the flow properties of a paper. [Copyright &y& Elsevier]

Modelica is a simulation language that is able to model systems from many different fields of scientific and engineering contexts, which can coexist in individual models. Modelica Standard Library is an open‐source library that contains many ready‐to‐use open‐source models built in Modelica language but does not have any code to determine transmission line parameters from its geometry, thus limiting its usability for power system studies. This paper first describes important issues arising when modelling power transmission lines, then presents how they can be solved using Modelica code. Readers of this paper will, therefore, be able to model power lines from the geometry of conductors using any of the existing (some freely available) Modelica‐capable simulation tools. [ABSTRACT FROM AUTHOR]

This study examined whether pilots operating a flight simulator completed digital or paper flight checklists more accurately after receiving postflight graphic and verbal feedback. The dependent variable was the number of checklist items completed correctly per flight. Following treatment, checklist completion with paper and digital checklists increased from 38% and 39%, respectively, to nearly 100% and remained close to 100% after feedback and praise for improvement were withdrawn. Performance was maintained at or near 100% during follow-up probes. [ABSTRACT FROM AUTHOR]

Abstract: Two categories of mathematical models were compared for the simulation of consolidation of paper coating structures, that is for the packing of pigments on a paper substrate under dewatering conditions. The first category uses probabilistic methods, relying on a random number generator to either determine the initial position of the pigments or their motion. The second category uses deterministic methods based on force balances. In this work, two probabilistic models and two deterministic models are described and their respective advantages and drawbacks are critically reviewed. Simulation results obtained using three of these methods are compared for the case of monodisperse and bidisperse spherical suspensions. Porosity calculations of the numerical packings obtained with the (deterministic) discrete element method (DEM) and two probabilistic methods, the Monte-Carlo (MCD) and the steepest descent (SDD) deposition methods, are compared with experimental data from the literature. These calculations reveal significant differences in the pore volume obtained with these three models. An analysis based on the bridging and relaxation phenomena that prevail in the flow of such particulate systems provide an explanation for these differences and show the strong potential of the discrete element method. The choice of the simulation method depends on the objective of the simulations. DEM will provide more accurate predictions of macroscopic quantities such as the porosity or the roughness, but requires very long computational times. MCD or SDD will only provide qualitative trends, but is computationally far less intense. A combination of strategies might be appropriate, using MCD (or SDD) to provide guidelines and DEM to enhance the results predicted by MCD. [Copyright &y& Elsevier]

The number of Printed Circuit Board (PCB) layers is continually increasing with the increase in data transmission rates, and the Signal Integrity (SI) of high-speed digital systems cannot be ignored. Introducing Vertical Interconnect Accesses (VIAs) in PCBs can realize the electrical connection between the top layer and the inner layers, however, VIAs represent one of the most important reasons for discontinuity between the PCBs and package. In this paper, a new optimization scheme for a differential VIA stub is proposed, with 3D full-wave numerical simulation used for modeling and simulation. Results show that this scheme optimizes the return loss and insertion loss while making the signal eye diagram more ideal, which can improve the transmission effect of high-speed signals. [ABSTRACT FROM AUTHOR]

In silico clinical trials (ISCTs) are an emerging method in modeling and simulation where medical interventions are evaluated using computational models of patients. ISCTs have the potential to provide cost-effective, time-efficient, and ethically favorable alternatives for evaluating the safety and effectiveness of medical devices. However, ensuring the credibility of ISCT results is a significant challenge. This paper aims to identify unique considerations for assessing the credibility of ISCTs and proposes an ISCT credibility assessment workflow based on recently published model assessment frameworks. First, we review various ISCTs described in the literature, carefully selected to showcase the range of methodological options available. These studies cover a wide variety of devices, reasons for conducting ISCTs, patient model generation approaches including subject-specific versus 'synthetic' virtual patients, complexity levels of devices and patient models, incorporation of clinician or clinical outcome models, and methods for integrating ISCT results with real-world clinical trials. We next discuss how verification, validation, and uncertainty quantification apply to ISCTs, considering the range of ISCT approaches identified. Based on our analysis, we then present a hierarchical workflow for assessing ISCT credibility, using a general credibility assessment framework recently published by the FDA's Center for Devices and Radiological Health. Overall, this work aims to promote standardization in ISCTs and contribute to the wider adoption and acceptance of ISCTs as a reliable tool for evaluating medical devices. Author summary: A new method for evaluating a medical device is an in silico clinical trial, where the device performance is tested using computational models representing a cohort of patients. Demonstrating that in silico clinical trials are reliable is clearly of paramount importance. However, little information is available on how to ensure this. In this paper we present a workflow for evaluating an in silico clinical trial. This workflow was developed by considering a wide-ranging sample of previously published in silico clinical trials, together with a detailed assessment of how specific model evaluation activities apply to in silico clinical trials. [ABSTRACT FROM AUTHOR]

The pinhole plate is a key component of the point diffraction interferometer (PDI). The reasonable improvement and simulation of this device would enhance the application of point diffraction interferometry technology during the measurement of wavefronts. The traditional point diffraction interferometry measurement method is easily disturbed by environmental noise, making it difficult to obtain high-precision dynamic measurements. This paper introduces a four-step phase-shift PDI that can be employed in a common optical path. By using the principle of the finite-difference time-domain method (FDTD), a simulation model of the orthogonal polarization point diffraction pinhole plate (OP-PDPP) structure is established. The results show that when Cr is used as the film material in the pinhole plate, the parameters include a film thickness of 150 nm, a pinhole diameter of 2 μm, a wire grid period of 150 nm, and a wire grid width of 100 nm; in addition, the comprehensive extinction ratio of the pinhole plate is the greatest and the diffraction wavefront error is the smallest. Finally, the constructed experimental system is used to test the wavefront of a flat sample with a 25.4 mm aperture, and the test results are compared with those of the ZYGO interferometer. The difference in the peak-to-valley (PV) value between the OP-PDI and the ZYGO interferometer measurement is 0.0028λ, with an RMS value difference of 0.0011λ; this verifies the feasibility of the scheme proposed in this paper. The experimental results show that the proposed OP-PDPP is an effective tool for high-precision dynamic measurement. [ABSTRACT FROM AUTHOR]

This paper deals with a low-cost method for the assembly of flexible substrate antennas and UHF RF identification silicon (Si) chips. Such a method exploits a magnetic coupling mechanism, thus not requiring for galvanic contacts between the Si chip and antenna itself. The magnetic coupling is established by a planar transformer, the primary and secondary windings of which are implemented on flexible substrate and Si chip, respectively. As a result, the Si chip can be assembled on the antenna with a mere placing and gluing process. First, the idea has been validated by theory. Electromagnetic simulations of a square heterogeneous transformer (1.0-mm side) show a maximum available power gain (MAG) of -0.4 dB at 868 MHz. In addition, the heterogeneous transformer is also quite tolerant with respect to misalignment between primary and secondary. An offset error of 150 \mu\ m reduces the MAG to -0.5 dB. A sub-optimal matching strategy, exploiting a simple on-chip capacitor, is then developed for antennas with 50-\Omega input impedances. Finally, the idea has been experimentally validated exploiting printed circuit board (PCB) prototypes. A PCB transformer (1.5-mm side) and a transformer rectifier (two-diode Dickson multiplier) have been fabricated and tested. Measurements indicates a MAG of -0.3 dB at 868 MHz for the transformer and the capability of the developed rectifier to supply a 220-\k\Omega load at 1.5 V with a -2-dBm input power. [ABSTRACT FROM AUTHOR]

Paper is a stochastic network of fibres, water and additives, and in that sense it may be envisaged as a composite material. Since fibres are much longer than the thickness of the paper sheet, the network is planar and almost two-dimensional. The two-dimensional structure governs many paper properties but the three-dimensional porous structure is also important. Insight into the structural changes that take place when paper is compressed in the paper machine may be gained by modelling and simulation of its viscoelastoplastic behaviour. The present work describes a mathematical model based on the cellular solids theory, characterising the nonlinear rheologic behaviour of the material. This approach results in an unsteady state problem and the resulting set of ODEs is solved by means of the DLSODES subroutine, which uses an integrator based in the Gear method. Experiments were conducted on a laboratory-scale dynamic press in order to validate the mechanical model. [Copyright &y& Elsevier]

A. V. Hill's 1938 paper ‘The heat of shortening and the dynamic constants of muscle’ is an enduring classic, presenting detailed methods, meticulous experiments, and the model of muscle contraction that now bears Hill's name. Pairing a simulation based on Hill's model with a reading of his paper allows students to follow his thought process to discover key principles of muscle physiology and gain insight into how to develop quantitative models of physiological processes. In this article, the experience of the author using this approach in a graduate biomedical engineering course is outlined, along with suggestions for adapting this approach to other audiences. [ABSTRACT FROM AUTHOR]

Extensive computer simulations have been carried out to model imbibition of a coating fluid into a paper. The microstructure of the paper''s pore space is represented by a network of interconnected channels or pore throats that are formed between the paper''s fibers. The geometrical characteristics of the channels, such as their effective radius and length, as well as their connectivity, are selected from the experimental data presented in Part II of this series. The imbibition process that we simulate is the result of forcing the coating fluid into the pore space by applying a time-dependent flow-driven pressure distribution to the external surface of the paper, or is driven only by capillary forces. The dynamic pressure distribution is representative of a high-speed coating process. The simulations indicate that the connectivity of the pore throats, the anisotropic structure of the paper''s pore space, and the dynamic pressure distribution all have a strong influence on imbibition of a coating fluid into a paper''s pore space and, hence, on the quality of the coating. [Copyright &y& Elsevier]

The vibration analysis of large and complex structures such as ships is difficult, because a vibrating ship hull (or its components) exhibits quite different vibration characteristics. Technological developments offer new concepts, definitions and comprehensive studies in the ship vibration field. The aim of this paper (bibliography) is to list references to papers, conferences, and proceedings dealing with ship vibrations that were published between January 2000 and April 2003. It contains 64 bibliographic references. The following types of ship vibrations are included: sea conditions, structural analysis, machine components, ship propulsive system, ship machines and special studies. Moreover, basic and brief information (reference, publication type, simulation models, utilizing methods and/or models, examined subject and/or problem) about grouped references has been given in the tables. So, this review paper not only lists references to papers at the millennium, but also helps researchers in their studies on ship vibration to find the necessary references quickly and practically. [ABSTRACT FROM AUTHOR]

This article presents information on the Leading Edge Paper Products, a complex management simulation created in Great Britain in 1990 by a team at the Cambridge Management Centres, now a part of consulting firm ASK Europe PLC and recently updated and introduced to North America. The objectives of the participants within this business leadership simulation are to make sense of large amounts of information about a fictional business, to create possible solutions to the issues found in the data, to share and seek relevant information, issues, and ideas with other participants, to create corporate strategies and prioritize actions, to influence and lead other participants, and to prepare and give a preliminary strategic plan for the company. The simulation requires a room set-up that simulates a business office, with office spaces for all participants. This can be done in a large meeting room, using tables as desks.

Research on collaborative manufacturing process modelling and simulation is of great significance in improving production efficiency and product quality, reducing costs, promoting collaborative work, and supporting decision-making. However, current studies have not offered the optimal costs of node enterprises participating in collaborative manufacturing, and ignored the impact of demand uncertainty of suppliers, manufacturers and customers on costs and economic benefits. Therefore, this paper aimed to study the collaborative manufacturing process modelling and simulation of production cost and economic benefit accounting analysis. First, this paper summarized three cost types, conducted cost accounting for the collaborative manufacturing process, and analysed its economic benefits. Second, based on the basic timed automata (TA) model, this paper used a timed input/output automata with port labels (Lp-TIOA) for modelling test cases of the simulation system. Finally, the experimental results verified the effectiveness of the constructed simulation model. [ABSTRACT FROM AUTHOR]

This article discusses the 2017 ACM SIGARCH/IEEE-CS TCCA Influential ISCA Paper Award, which was given to the 2002 ISCA paper, “Drowsy Caches: Simple Techniques for Reducing Leakage Power.” [ABSTRACT FROM AUTHOR]

Modular robots carry the unique advantage of changing their shape according to different tasks and environments. In order to study the lightweight and flexible combination characteristics of modular robots, this paper presents a two-degree-of-freedom pluggable modular robot and its simulation method, named SnackBot. SnackBot is composed of several independently operating modules. Each module contains a control unit, a micro battery, and two DC motors that drive the module joints. In order to predict robot actions and monitor the state of the robot, the simulation model of SnackBot is built and a virtual environment is established in Ignition Gazebo. The virtual robot and physical robot are synchronously controlled in the environment of the Robot Operating System 2 (ROS2). Finally, experimental results verify the feasibility of the SnackBot. [ABSTRACT FROM AUTHOR]

Virtual reality software has evolved to create ever more realistic virtual environments. Sophisticated virtual education laboratory experiments are now possible. Some educators and researchers question the value of hands-on laboratories relative to virtual laboratories. Researchers have investigated students' acceptance of virtual laboratories and the relative effectiveness of virtual laboratories compared to traditional hands-on laboratories. Research results indicated that students' attitudes toward virtual laboratory experiments are positive, and researchers found virtual laboratory experiments to be as effective as or more effective than traditional hands-on laboratories. However, researchers have not measured simulated laboratory effectiveness for all standard education laboratory goals. Simulated laboratory technology will be part of science education, but how to introduce laboratory simulations and the appropriate role for simulated laboratories remains a subject of debate. Are virtual laboratory experiments acceptable substitutes for hands-on laboratories in secondary education? To explore this question, laboratory goals and effectiveness criteria must be defined and measured for secondary education. This paper explores the goals and effectiveness of virtual and hands-on education laboratories. This paper also outlines the arguments for and against the replacement of traditional hands-on labs with simulated laboratories in secondary science education and makes a case for using laboratory simulations to supplement rather than replace traditional hands-on laboratories. [ABSTRACT FROM AUTHOR]

Abstract: We study the deviations for the results of the properties of a hard-sphere gas near the walls of a micro/nano channel using the hybrid MD–MC simulation method compared to the pure MD and MC results. Our model for the micro channel consists of two parallel infinite plates situated at distance L apart from each other, and of gas molecules confined between these two walls. We study the dependence of the deviations for higher densities, considering different lengths of the different simulation domains in the hybrid MD–MC method. We find that when density is increased, the deviations in the pure MC results are increasing compared to pure MD results. The deviations in the hybrid simulation results are decreasing and are very small when increasing the width of the solid–gas interface. The deviations of the pure MC simulation results from the pure MD simulation results for the number density are found to be around 0.9%, when the reduced density and the width of the channel , where λ is the mean free path. When the hybrid method is used, the deviations are decreasing with a factor from two to three, and are between 0.32%–0.42%. For more dense gas (), the deviations of the MC simulation results for the number density are found to be 1.71%, and the deviations of the hybrid MD–MC simulation results between 0.246% and 0.6977%. We discuss how these deviations in case of a dense gas () depend on the width of the interface, and we study it for the case when the MD domain is 10% and MC domain is 90% from the simulation domain, and also for the case when the MD domain is 50% and MC domain 50% from the whole simulation domain. For more dilute gas, the MC, MD and hybrid MC–MD simulations are in very good agreement and the deviations are negligible. [Copyright &y& Elsevier]

Presents an introduction to the June 2005 issue of the journal "Simulation & Gaming."

The article presents a study which examines the accuracy of iron pipe corrosion as a simulation model for a water supply network. The study conducts test rig experiments for the water treatment plants (WTP) of Riga City in Latvia to measure the average corrosion rates. Results show positive correlation for underground source water between corrosion rate on pipe wall inner surface and the flow velocity.

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]

An inverse transport modeling approach based on the concepts of sequential importance resampling and parallel computing is presented to reconstruct altitude-resolved time series of volcanic emissions, which often can not be obtained directly with current measurement techniques. A new inverse modeling and simulation system, which implements the inversion approach with the Lagrangian transport model Massive-Parallel Trajectory Calculations (MPTRAC) is developed to provide reliable transport simulations of volcanic sulfur dioxide (SO2). In the inverse modeling system MPTRAC is used to perform two types of simulations, i. e., large-scale ensemble simulations for the reconstruction of volcanic emissions and final transport simulations. The transport simulations are based on wind fields of the ERA-Interim meteorological reanalysis of the European Centre for Medium Range Weather Forecasts. The reconstruction of altitude-dependent SO2 emission time series is also based on Atmospheric Infrared Sounder (AIRS) satellite observations. A case study for the eruption of the Nabro volcano, Eritrea, in June 2011, with complex emission patterns, is considered for method validation. Meteosat Visible and InfraRed Imager (MVIRI) near-real-time imagery data are used to validate the temporal development of the reconstructed emissions. Furthermore, the altitude distributions of the emission time series are compared with top and bottom altitude measurements of aerosol layers obtained by the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) satellite instruments. The final transport simulations provide detailed spatial and temporal information on the SO2 distributions of the Nabro eruption. The SO2 column densities from the simulations are in good qualitative agreement with the AIRS observations. Our new inverse modeling and simulation system is expected to become a useful tool to also study other volcanic eruption events. [ABSTRACT FROM AUTHOR]

For the control of the outlet flow rate of a constant-flow water-saving device under different water pressures, this study developed and implemented a custom User-Defined Function (UDF) program to simulate the dynamic motion of the water-saving valve within the Fluent environment. This simulation realistically represents the valve's behavior under varying water pressures, thereby accurately predicting the valve opening height to comply with national regulatory standards. Firstly, a dynamic grid transient CFD simulation model of the water-saving valve was established using a Fluent UDF program written in C language. The parameters of the elastic elements in the water-saving device flow control system were designed to achieve control of the outlet flow rate. Then, the benchmarking analysis of the aforementioned simulation model was completed based on the flow rate test results of the water-saving device. Finally, the relationship between physical quantities and flow field distribution characteristics of the water-saving valve was analyzed under three different water pressures specified in the national standard. Based on the optimization calculations, the valve opening heights under three different water pressures were obtained, ensuring that the outlet flow rates meet the regulatory standards set by the national authorities. Compared with traditional methods that rely solely on steady-state simulations or empirical data, the method proposed in this paper represents a significant advancement. [ABSTRACT FROM AUTHOR]

As the demand for miniaturization of thermal management systems for electronic devices rises, numerous researchers are dedicating their efforts to the study of single-phase forced convective heat transfer (FCHT) within nanoscale channels. However, investigating FCHT in nanochannels (FCHT-NC) using experimental and theoretical methods is challenging. Alternately, molecular dynamics (MD) simulations have emerged as a unique and powerful technique in recent years. This paper presents a comprehensive review of the application of the MD simulation method in the study of FCHT-NC. Firstly, the current paper reviews various simulation techniques and models, along with their associated primary parameters employed in FCHT-NC, through a detailed and systematic literature survey and critical analysis. Evaluating the current methods and discussing their limitations provide helpful guidelines for future studies. Furthermore, based on the existing literature in the MD simulation, this review outlines all influencing parameters on the performance of FCHT-NC, covering their effects and discussing underlying mechanisms. Finally, key challenges and future research directions are summarized in this review, thereby providing essential support for researchers seeking to apply the MD simulation method to investigate FCHT-NC. [ABSTRACT FROM AUTHOR]

Under the condition of grid voltage imbalance, the circulation of the bridge arm inside the modular multilevel converter (MMC) increases significantly, which leads to the aggravation of the distortion of the bridge arm current, and, thus, increases the system loss and reduces the power quality. To address this problem, this paper analyzes the mechanism of circulating current generation and proposes a circulating current suppression strategy based on a reduced-order generalized integrator (ROGI), which firstly uses the ROGI system to separate the second-harmonic positive- and negative-sequence components in the circulating current from the DC, and then converts the rotating coordinates of the circulating current's second octave component into the DC to be fed into the proportional–integral quasi-resonance (PIR) controller for suppression. A simulation model of a 23-level MMC inverter is built in MATLAB/Simulink, and the control strategy proposed in this paper is compared with the classical proportional–integral (PI) control in simulation experiments. The simulation results show that the amplitude of the circulating current fluctuation of the classical PI control is reduced from 90 A to 22 A, and the harmonic distortion rate of the bridge arm current is reduced from 32.56% to 5.57%; the amplitude of the circulating current fluctuation of the control strategy proposed in this paper is reduced from 90 A to 5.7 A, and the harmonic distortion rate of the bridge arm current is reduced from 20.2% to 1.13%, which verifies the effectiveness of the pro-posed control strategy. [ABSTRACT FROM AUTHOR]

This paper uses big data technology to extract the electromechanical fault characteristics of metro vehicles and analyze the current situation under different fault conditions to ensure the operation quality and safety of metro operations. It also establishes a simulation model to simulate the current waveform of metro vehicles under different fault conditions and analyze the fault phenomenon. The simulation test results show that: (1) The current waveform of a single transistor with the hard fault is compared with the simulated current waveform under a normal state. The upper part of the A phase current waveform is lost when T1 fails. When T2 fails, the current waveform in the lower half of the C phase current is lost. When T3 fails, the upper half of the B phase current waveform is lost. (2) The current waveform in the hard fault's upper and lower bridge arms will have phase loss. In the T25 fault, the C phase current is completely lost. In the T14 fault, the phase A current waveform is completely lost. In the T36 fault, the phase B current is completely lost. (3) The current waveform of a single transistor with a soft fault is complete, but the overall current amplitude is reduced. When a T1 fails, the A phase current tends to rise first and then fall. Compared to normal, the amplitude of the current decreases, and the peak decreases slightly. (4) The current values of phase B and phase C of the two transistors on the same bridge above and below the soft fault are mostly the same. The phase A current output value decreases in both the positive and negative half cycles. This paper aims to improve the monitoring ability of the monitoring system of electromechanical equipment of metro vehicles, which plays a specific role in maintaining the safety of subway operations and improving the quality of subway operations. [ABSTRACT FROM AUTHOR]

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