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The present work investigates the energy performance analysis of a heptad‐based multiple‐stage evaporator (MSE) under steady and transient conditions, integrated with different energy reduction schemes (such as steam split, feed split, and feed preheater). The steady‐state analysis was performed to optimize the steam economy subjected to the developed steady‐state energy models as the equality constraints. The simulated optimization is a maximization problem and is solved by Interior‐Point Optimizer and Gray Wolf Optimizer on two different platforms, GAMS and MATLAB, respectively. Further, transient and stability analyses were performed by developing and representing the nonlinear dynamic energy models to the state‐space representation using linearization. [ABSTRACT FROM AUTHOR]

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]

How to monitor the freshness of packaged food, the safety of sealed medicine, or the other substances in sealed space wirelessly and environment‐friendly has become an urgent problem in recent years. After summarizing the theory of the LC sensor, a design of a paper‐based resonator (30 mm × 30 mm × 0.15 mm) consisting of a finger capacitor is proposed in this paper. The sensor is embedded inside the package by adhering it to the package's inner wall. Its response is remotely detected through a readout coil. This paper establishes a circuit simulation model and an electromagnetic simulation model to verify the feasibility of the design. Compared with the real object and the theoretical simulation model, the difference between the results only within 1 MHz, which verifies the correctness of the theory. Additionally, the measured results indicate that the resonant frequency of the resonator shifted from 102.441 MHz to 88.195 MHz, after dropping water on the sensor. Besides, the simple fabrication technology and inexpensive sensor material ensure a low cost, thus making this technology economically viable. [ABSTRACT FROM AUTHOR]

This paper aims to develop a construction and operation cost model of wastewater treatment for the paper industry in China and explores the main factors that determine these costs. Previous models mainly involved factors relating to the treatment scale and efficiency of treatment facilities for deriving the cost function. We considered the factors more comprehensively by adding a regional variable to represent the economic development level, a corporate ownership factor to represent the plant characteristics, a subsector variable to capture pollutant characteristics, and a detailed-classification technology variable. We applied a unique data set from a national pollution source census for the model simulation. The major findings include the following: (l) Wastewater treatment costs in the paper industry are determined by scale, technology, degree of treatment, ownership, and regional factors; (2) Wastewater treatment costs show a large decreasing scale effect; (3) The current level of pollutant discharge fees is far lower than the marginal treatment costs for meeting the wastewater discharge standard. Key implications are as follows: (l) Cost characteristics and impact factors should be fully recognized when planning or making policies relating to wastewater treatment projects or technology development; (2) There is potential to reduce treatment costs by centralizing wastewater treatment via industrial parks; (3) Wastewater discharge fee rates should be increased; (4) Energy efficient technology should become the future focus of wastewater treatment. [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: In this paper, we address some computational challenges arising in complex simulation-based design optimization problems. High computational cost, black-box formulation and stochasticity are some of the challenges related to optimization of design problems involving the simulation of complex mathematical models. Solving becomes even more challenging in case of multiple conflicting objectives that must be optimized simultaneously. In such cases, application of multiobjective optimization methods is necessary in order to gain an understanding of which design offers the best possible trade-off. We apply a three-stage solution process to meet the challenges mentioned above. As our case study, we consider the integrated design and control problem in paper mill design where the aim is to decrease the investment cost and enhance the quality of paper on the design level and, at the same time, guarantee the smooth performance of the production system on the operational level. In the first stage of the three-stage solution process, a set of solutions involving different trade-offs is generated with a method suited for computationally expensive multiobjective optimization problems using parallel computing. Then, based on the generated solutions an approximation method is applied to create a computationally inexpensive surrogate problem for the design problem and the surrogate problem is solved in the second stage with an interactive multiobjective optimization method. This stage involves a decision maker and her/his preferences to find the most preferred solution to the surrogate problem. In the third stage, the solution best corresponding that of stage two is found for the original problem. [Copyright &y& Elsevier]

Highlights: [•] Estimation of GHG emission and energy consumption in wastewater treatment plants. [•] On-site and off-site emissions of carbon dioxide, methane, and nitrous oxide. [•] Higher GHG emission in anaerobic and hybrid plants due to higher CH4 generation. [•] Recovery and use of biogas satisfy the energy demands of treatment systems. [•] Higher off-site than on-site GHG emissions due to the use of fuel and material. [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]

This paper aims to investigate the impact of moisture on mechanical properties of insulation paper. According to the molecular modeling approach proposed by Theodorou, the amorphous cellulose models of insulation paper with different moisture contents were built up to calculate mechanical parameters and hydrogen bond networks. And relevant conclusions could be drawn through further analysis on these calculation results: water molecules can destroy hydrogen bond network between the neighboring cellulose molecules, which might be responsible for the significant decrease of Young's modulus and other mechanical parameters, while no appreciable effect of intramolecular hydrogen bonds on mechanical properties was detected. Thus tensile tests were also carried out to study the moisture influence on the Young's modulus, by which the result of the simulation was approved. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to analyze and quantify the environmental impacts associated with the production of testliner paper using 100 % recovered paper as fiber raw material, by applying the life cycle assessment principles. A simulation of advanced sorting technology was done to prepare and use batches of raw materials with different levels of contaminants. Comparative studies of environmental impact assessment were focused on the quality of recovered paper, which is decisively influenced by the efficiency of the sorting process. The particularity of the study is that so far it is the only one that analyzes the environmental impact generated by recovered paper quality. Methods: To analyze the environmental impacts in the scenarios, life cycle assessment methodology was considered. Potential environmental impacts were assessed by using the CML , Dec.07 method developed by the Centre for Environmental Science from the University of Leiden. Results and discussion: In this study, acidification potential, abiotic resources depletion potential, eutrophication potential, global warming potential, photochemical ozone creation potential, and human toxicity potential were the impact categories analyzed. Considering that the system boundaries refer only to the paper mill that was obtained, all unitary processes involved in the manufacturing of product system influence in varying proportions the impact categories chosen for evaluation. A higher concentration of contaminants leads to a higher amount of energy and water used, and thus, a significant amount of waste and emissions generated. Simulations performed have highlighted the importance of sorting technology that influences the quality of raw material that will be used. Conclusions: Utilization of recovered paper batches with a low quality contributes to an increased environmental impact associated with the testliner paper manufacturing stage. A low quality of recovered paper will influence energy consumption in different modules of the system (recycled fiber pulp preparation, paper machine, and wastewater treatment), the volume of waste generated, and consequently the emissions released both in air and water. [ABSTRACT FROM AUTHOR]

In pulp and paper the modelling and simulation of the pulp production processes was the first major application. Since then several other applications have been realised though papermaking has never been on the lead concerning the use of computer-based modelling and simulation. The complex nature of the materials is one of the most demanding challenges and the biggest hurdle for any electronic description of the papermaking process or paper itself. So other industries took the lead and it is now for the paper industry to learn from these industries what can be done with the help of computers to control or optimise processes or to design new grades. The application of results gained with the use of modelling and simulation techniques in pulp and paper manufacturing processes has helped the industry to, for example, reduce emissions and increase the productivity and cost-efficiency of the processes. Still there are many important tasks open. A better understanding of the mechanisms of the processes and their control loops has to be achieved in order to further improve the paper quality, stabilise the wet-end chemistry, and enhance the runnability. Important features to be developed are new process designs, efficient process monitoring and systems that offer decision support during operation. In this paper a review of the state of the art on modelling and simulation in the pulp and paper industry is presented as well as further research needs. [ABSTRACT FROM AUTHOR]

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]

Paper curls in printers should be prevented since they cause paper jams and degradation of printing quality. Moisture transport due to high temperature in the fuser nip of a printer is one of main reasons for paper curls. In order to predict and control the paper curls, it is therefore essential to understand the mechanisms of heat and moisture transport in paper. In this paper, we derived a coupled heat and moisture transport model and applied it to the situation where a paper sheet moves between two rollers having different temperatures in a fuser nip. A series of simulations were carried out with varying parameters related to the characteristics of printer paper, the environment, and paper/environment interfaces. The simulation results provided a deep understanding of the moisture transport mechanisms and identified several key variables affecting changes of moisture profiles as a function of time. The time-dependent moisture contents data will be fed into a mechanical model to obtain the quantitative amount of the nip curl. [ABSTRACT FROM AUTHOR]

Abstract: Compared to traditional steel metering blades commonly used in paper coating operations, ‘soft-tip’ metering blades have received considerably less attention. The research presented herein concerns computationally detailing the characteristics of deformation and deflection in soft-tipped blades under the influence of coating colour flow. Multiphysics simulations were conducted to assess the interrelationships between deflection, deformation, blade length and material properties. Localised plastic deformation in the soft-tip material may be manipulated by adjusting the material properties and geometries of the tip material alongside variables such as; the free blade length, the speed and the properties of the incoming coating. Design of soft-tip materials with respect to these factors may make it easier to achieve a desired blade tip and hence, coating characteristic. [Copyright &y& Elsevier]

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]

Abstract  A skew of a paper transferred by rubber rollers in printers is simulated by FEM software. Effects of an imbalance of preload, an imbalance distribution of coefficient of friction and a front tension on the paper skew are investigated and how to determine the skew direction are shown. A simulation model is composed of a feed roller, a preload roller and a paper. The feed roller is rotated forcibly by a certain degree at every calculation step and a deformation, displacement and strain of the paper and rollers are calculated. A series of calculation results is shown as a motion simulation. The results show that the paper skews to the smaller preload side, to the smaller coefficient of friction side, or to the opposite side of the front tension. Further, effects of a skew prevention guide plate is simulated. [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]

The increasing costs associated with water supply and the disposal of wastewater has stimulated industries to seek more efficient water management systems. Mathematical modelling and simulation can be a very valuable tool for the study of the multiple alternatives available whilst assessing optimum solutions for water management in industry. This study introduces a new steady state model library able to reproduce industrial water circuits. It has been implemented in a novel software framework for the representation, simulation and optimization of industrial water networks. A water circuit representing a paper mill has been modelled and simulated showing the capability to reproduce real case studies. Alternative scenarios for the water network have also been tested to assess the capability of the models to optimize water circuits minimizing total cost. [ABSTRACT FROM AUTHOR]

The article discusses about the Data and Code Availability Policy. It states that it is the policy of the American Economic Association to publish papers only when the data and code used in the analysis. For the econometric, simulation, and experimental papers, the replication materials must include the dataset, description for access and the programs used to create any final and analysis datasets from raw data.

The article discusses the study which develops a dynamic modular paper machine simulator package. It has been noted that computer simulation can be a valuable tool for the optimization of paper production processes, designing wastewater closure strategies and the visualization of a complicated process. It shows that by structuring the simulator as a set of modular blocks, a variety of configurations can be modeled by assembling the blocks in different ways. In addition, researchers have recommended that the simulator package can help in developing simple models for the simulation of complex dynamic systems.

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]

The article reports on the significance of Jacobian module for advanced pulp and paper simulation and control. As stated, the module empowers automatic bumps on the manipulated variables to compute process gains at different operating points. It also allows the control system designer to assess loop interactions in a multivariable control system by calculating the Relative Gain Array (RGA) matrix, of which the Jacobian is an essential part. In addition, the Jacobian dynamically linked modules (DLM) and requires the user to determine a number of variables in the flow sheet drawing interface and the Jacobian module will calculate some other variables during simulation.

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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]

• Robust functional form contains true parameters far more often than popular models. • Matches/outperforms widely used regression and Neural Network models. • Finds appropriate balance between Model Fit, Inference and Prediction (MIPs). • Introduces new large-sample DGP test; can use to improve A.I. models. • For MIS field finds Popularity Parameter to be important for predicting citations. This article introduces a versatile functional form for Generalized Linear Models (GLMs) through a simple, yet effective, transformation of the current framework. The models are applied through a new hierarchical bayesian estimation procedure for logistic regression to highly-cited papers in the Management Information Systems (MIS) field. The results are uniformly better, in regards to model fit and inference for in-sample and out-of-sample data, for simulation studies and real-world data applications, requiring very little time to convergence to true population parameters. In simulation studies, I show that the method contains the true parameters nearly three times as often as widely used existing GLMs, and does so while having confidence intervals that are 54.50% smaller, while requiring around two-thirds the number of MCMC iterations as existing bayesian methods. In Scientometric applications the methodology is shown to be highly robust with predictive/classification accuracy, either equaling or exceeding existing methods for identifying highly-cited articles including Artificial Neural Networks (ANN). Thus, the method is shown to be robust to the amount of asymmetry (or symmetry) of the probability of success (or failure) and robust to unbalanced samples and varying Data Generating Processes. Further, the methodology is equivalent to current methods if the data support them and is therefore complementary to existing methods, without loss of interpretability of model parameters. For the MIS field it finds that Popularity Parameter (PP) of an article Keywords can predict whether a paper will be highly-cited (top 25% of highly-cited articles) between two to three years after publication and beyond. Furthermore, given the small number of iterations needed for convergence, the methodology can also be used as a baseline method in Big Data (BD) settings for both Artificial Intelligence (AI) and Machine Learning (ML) contexts as well. [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: Depending on unique operation characteristics for voltage applied on valve side winding of the converter transformers, it is extraordinarily significant to study the partial discharge (PD) behavior with oil-paper insulation under combined AC–DC voltage. Therefore, this paper investigated PD inception characteristics by pulse current methods with needle-plate electrode system under combined AC–DC voltage. Furthermore, 3D electric field distributions versus combined AC–DC voltage in different ratios were calculated by Finite Element Analysis (FEA). An experimental conclusion was drew that AC partial discharge inception voltage (PDIV) in pure oil would decrease linearly with the DC component increasing but the inception voltage with oil-paper insulation appeared to be independent of DC voltage and dependent of AC voltage. And 3D electric field distribution deduced from simulation provided a supplementary proof on the experimental results. Moreover, high speed photography was used to capture emitted light produced by discharge, estimate streamer velocity (1.8 km/s) and record streamer initiation and propagation process in oil gap. Previous studies have shown that the prebreakdown phenomena involving the generation and propagation of vapor channels through the oil could be divided into a three-stage process. [Copyright &y& Elsevier]

Abstract: Recycling activities have demonstrated a remarkable increase over the last decade due to the economic and environmental dimensions of sustainability. In particular, capacity planning in production facilities has become a strategic issue of key importance affecting the profitability of the recycling industry. By integrating the simulation discipline and the feedback control theory into a dynamic consideration of recycling networks, this paper proposes a System Dynamics (SD) model for strategic capacity planning in the recycling industry. The decision-making process is based on a balanced tradeoff between profit and capacity utilization for a single producer with closed-loop recycling activities. The SD model captures physical stocks and flows apparent in real-world recycling networks and includes the feedback mechanisms which regulate these flows. When used as an “experimental tool”, the model tests alternative capacity planning policies and demonstrates policy suggestions for the forward and reverse channels, which maximize profitability over a strategic planning horizon. This experimentation is illustrated by using data from a paper producer with recycling activities, as a real-world test case. Extensive simulation runs, investigate the efficiency of a wide range capacity acquisition decisions, using total company profit as the measure of performance. Although such an analysis may differ from one recycling network to another, it has been kept as generic as possible to facilitate its applicability to a wide-spectrum of real-world local, regional or global networks. [Copyright &y& Elsevier]

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]

A three-dimensional model of the steam ejector heat pump for the dryer section of the paper machine was developed by applying the Computational Fluid Dynamics (CFD) technique, which provided the pressure and velocity distributions of fluid flow in heat pump. The results indicated that the fluid velocity field in heat pump has an incomplete axially symmetrical distribution. The entrainment ratio of the heat pump initially increases rapidly with the increase of the ejected steam inlet pressure and then decreases after the inlet pressure exceeds one certain value. There exists a critical value for the mixed fluid pressure under the given operating conditions. The optimal ratio of the diameter of constant area mixing section to the steam nozzle throat diameter is about 3.4 and the optimal ratio of length to diameter of constant area mixing section L/D m is 6. An optimal divergence angle of diffuser was observed under different diffuser length. There is an optimized steam nozzle position under the given operating condition where the maximum of entrainment ratio was observed. The CFD technique is found to be an efficient alternative to predict the ejector performance and the conclusions of the research can provide a beneficial reference for structural optimization design of ejector. [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]

Abstract: Costa''s dirty paper coding (DPC) offers a good framework for precoding for transmission over additive Gaussian channels with additive states non-causally known at the transmitter but not at the receiver. In this paper, rate calculation, error probability analysis and code design for DPC are investigated from a practical point-of-view. Based on Monte-Carlo numerical integration and simulations, we first show that the gap to the full AWGN capacity can be partially bridged using some finite-dimensional lattices with good packing and quantizing properties. Then the difficult problem of codebook selection is addressed through some illustrative examples. Analysis sheds light on the dual roles of “packing” and “shaping” as well as on their inter-connection at finite-dimensional coding, by opposition to the asymptotic case (i.e., infinite dimension) where the two coding components are decoupled. [Copyright &y& Elsevier]

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]

Systems engineering activities in the concept and development phases have evolved continuously for decades. The deployment of digital thread, digital engineering, MBSE approaches, and modeling and simulation techniques have driven part of this evolution. Despite this trend, requirements are still largely textual and expressed in natural language, and requirements engineering activities are still often document‐based. However, model‐based requirements‐engineering approaches have emerged in recent years and have demonstrated significant benefits, including improved requirements quality, less ambiguity, and early and efficient verification and validation. The goal of this paper is to present the current outcomes and perspectives of setting up an Integrated Digital Requirements Engineering approach as developed within our company. This approach seeks to optimize usability and maximize benefits to support end‐to‐end V&V activities while fully integrating into MBSE workflows. [ABSTRACT FROM AUTHOR]

Highlights: [•] A dynamic model for longitudinal vibration assisted guillotining of paper is developed. [•] Empirical model of a stack of thin paper material is identified. [•] Novel measurement procedure for determining dynamic behavior for ultrasonic assisted cutting is developed. [•] Simulated cutting forces are in agreement with the experimentally recorded cutting forces. [Copyright &y& Elsevier]

Cellulose partially converted to dialcohol cellulose has been identified as a potential breakthrough material for the production of bio-based, complex, double-curved surfaces due to its extensive strain-at-break characteristics (reaching as great as 80% in tensile loading). Tensile testing of handsheets made from modified cellulose fibers was conducted from 50 to 90% relative humidity (RH) and from 23 to 150 °C. Strain-at-break of the handsheets ranged from 35 to 80% over this humidity and temperature range, which is significantly greater than typical cellulose-based materials. The combined effect of moisture and temperature was further investigated by dynamic mechanical thermal analysis, which was utilized to determine the glass-transition temperature of the handsheets as a function of relative humidity. Based on the tensile test results and verified by the three-dimensional (3-D) forming and simulation, a forming limit diagram (strain-based failure surface which describes and illustrates the formability of the material) for the handsheets was generated. This forming limit illustrates significant extent to which this bio-based material can be 3-D formed into advanced structures. Furthermore, temperature was identified as the best, quickest, and most controllable method of improving extensibility of this material during 3-D forming. [ABSTRACT FROM AUTHOR]

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 Activated Sludge Model No. 1 was chosen as the basis for model development and was modified to take into account the specific characteristics of pulp and paper effluents. The model was incorporated to the GPS–X simulation environment (Hydromantis, Hamilton, Ontario, Canada) to study operating deficiencies and nutrient transformations, particularly in relation to hulking. The results show that the process of ammonification is not significant at the studied mill and that the process of phosphatification (transformation of soluble organic phosphorus into orthophosphates) seems to be related to settling problems, as indicated by the sludge volume index. The phosphatification rate and the standard oxygen–transfer efficiency were found to decrease as the system entered a bulking state. Understanding the behavior of pulp and paper activated sludge can be improved by the incorporation of industry– specific processes and components to comprehensive models. These models then can be used to gain insight to the causes of bulking. Water Environ. Res., 82, 362 (2010). [ABSTRACT FROM AUTHOR]

The paper industry is a highly automated industry that includes many different production steps, in which a variety of machine components are used. In a paper machine, where the pulp is being transformed into paper, rotating components such as bearing-mounted rollers play an important part in driving the wire with the pulp through the process. In this type of industry with a serial layout, the failure of a single roller or bearing could lead to the stoppage of several production steps, with costly consequences as a result. To ensure and optimise asset availability, a condition-based maintenance (CBM) strategy could be implemented. However, CBM is dependent on an appropriate condition monitoring (CM) technique to detect a physical phenomenon that defines the state of critical components or systems. For the development of CM techniques, it is therefore important to understand and model the physical behaviour of the system in question. In this paper, the behaviour of a roller in a paper machine is analysed using the finite element method (FEM). The physical model was compared with vibration measurements collected from an online monitoring system and an experimental modal analysis. [ABSTRACT FROM AUTHOR]

By simulating the change process of the inventory of scientific papers according to a mathematical model of the publishing process, we find that publication delay would cause statistical error of the scientific paper output indicator, i.e. the quantity of published papers. Based on a simulation model and the average publication delay, we construct an optimization algorithm of the actual scientific paper output using a nonlinear least squares algorithm and validate its accuracy. To simplify the solution process, we propose an approximate algorithm of the actual scientific paper output indicator which would help science and technology managers practically deduce an approximation of the actual indicator. This has implications for strategy decision making and allocation of resources for science and technology research by policy makers. [ABSTRACT FROM AUTHOR]

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]

This paper explores applying the optical characterization methodologies in IEC 62679 and ISO 9241 to reflective e‐paper displays (EPDs). Measurements of specular and diffuse reflection properties are presented. Simulations and measurements show that EPDs fulfill the ISO requirements for minimum contrast ratio over a wide range of illumination conditions. [ABSTRACT FROM AUTHOR]