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Abstract: This paper investigates the skiving and cutting stock problem (SCSP) encountered in the paper and plastic film industries, in which a set of nonstandard reels generated from previous cutting processes are used to produce finished rolls through the skiving and cutting process. First, reels are skived together lengthwise to form a reel‐pyramid (a polygon), and then the reel‐pyramid is cut into finished rolls of small widths. Depending on if a reel can be divided lengthwise into subreels to form the reel‐pyramid, the problem can be classified into divisible SCSP (DSCSP) and indivisible SCSP (ISCSP). In this paper, two integer programming (IP) models are proposed for DSCSP and ISCSP, respectively. A sequential value correction procedure combined with the two IP models (SVCTIP) is developed to solve the two SCSPs. The effectiveness of the SVCTIP is demonstrated through extensive computational tests. [ABSTRACT FROM AUTHOR]

Abstract: Strains, computed by the finite element method, are evaluated and compared to an experimentally determined strain field. The analyzed low-density paper has been designed to ensure bond–breakage as the dominating damage mechanism and the paper material is approximately in-plane isotropic. An optical non-contact displacement measuring system has been used in fracture tests to determine the strain field in the crack-tip region of a pre-fabricated crack. Additionally, acoustic emission monitored tensile tests have been conducted to determine onset and evolution of damage processes and thereby enabling calibration of required constitutive parameters. The results suggest that the investigated paper material can tolerate significantly higher strains than what is predicted by a classic elastic–plastic J 2-flow theory. Immediately before onset of the final fracture (i.e., localization), the experimental measured normal strain in the near-tip region is around 60% higher than the computed strain when using exclusively an elastic–plastic theory for the corresponding load while the strain computed utilizing a non-local damage theory is of the same order of magnitude as the experimentally measured strain. Hence, it seems essential to include a non-local continuum theory to describe strains in the near-tip region quantitatively correct for paper materials. It is demonstrated that path independence of the well-known J-integral does not prevail for this class of material models. Only for the special situation of a homogenous damage field in the crack-tip region may the stress and strain fields be described by the well-known HRR-solutions. [Copyright &y& Elsevier]

ABSTRACT The next-generation seismic imaging algorithms will consider multiple scattering as indispensable information, being referred to as Full-Wavefield Migration. In addition, these algorithms will also include autonomous velocity updating in the migration process, being referred to as Joint Migration Inversion. Full-Wavefield Migration and Joint Migration Inversion address the industrial needs to improve images of very complex reservoirs as well as the industrial ambition to produce these images in a more automatic manner (automation in seismic processing). In this vision paper on seismic imaging, Full-Wavefield Migration and Joint Migration Inversion are formulated in terms of a closed-loop estimation algorithm that can be physically explained by an iterative double focusing process (full-wavefield common-focus-point technology). A critical module in this formulation is forward modelling, allowing feedback from migrated output to unmigrated input (closing the loop). For this purpose, a full-wavefield modelling module has been developed, which utilizes an operator description of complex geology. The full-wavefield modelling module is pre-eminently suited to function in the feedback path of a closed-loop migration algorithm. 'The Future of Seismic Imaging' is presented as a coherent trilogy, proposing the migration framework of the future in three consecutive parts. In Part I, it was shown that the proposed full-wavefield modelling module algorithm differs fundamentally from finite-difference modelling because velocities and densities need not be provided. Instead, an operator description of the subsurface is used. In addition, the concept of reverse modelling was introduced. In Part II, it is shown how the theory of Primary Wavefield Migration can be extended to Full-Wavefield Migration by correcting for angle-dependent transmission effects and by utilizing multiple scattering. The potential of the Full-Wavefield Migration algorithm is illustrated with numerical examples. A multidirectional migration strategy is proposed that navigates the Full-Wavefield Migration algorithm through the seismic data cube in different directions. [ABSTRACT FROM AUTHOR]

ABSTRACT The next generation seismic imaging algorithms will consider multiple scattering as indispensable information, referred to as Full Wavefield Migration. In addition, these algorithms will also include autonomous velocity updating in the migration process, referred to as Joint Migration Inversion. Full wavefield migration and joint migration inversion address the industrial needs of improving images of very complex reservoirs as well as the industry ambition of producing these images in a more automatic manner ('automation in seismic processing'). In this vision paper on seismic imaging, full wavefield migration and joint migration inversion are formulated in terms of a closed-loop, estimation algorithm that can be physically explained by an iterative double focusing process (full wavefield Common-Focus-Point technology). A critical module in this formulation is forward modelling, allowing feedback from migrated output to unmigrated input ('closing the loop'). For this purpose a full wavefield modelling module has been developed that utilizes an operator description of complex geology. Full wavefield modelling module is pre-eminently suited to function in the feedback path of a closed-loop migration algorithm. 'The Future of Seismic Imaging' is presented as a coherent trilogy, proposing in three consecutive parts the migration framework of the future. In part I it was shown that the proposed full wavefield modelling module algorithm differs fundamentally from finite difference modelling, as velocities and densities need not be provided. Instead, full wavefield modelling module uses an operator description of the subsurface. In Part II it was shown how the theory of Primary Wavefield Migration can be extended to Full Wavefield Migration by correcting for elastic transmission effects and by utilizing multiple scattering. In Part III it is shown how the full wavefield migration technology can be extended to Joint Migration Inversion, allowing full wavefield migration of blended data without knowledge of the velocity. Velocities are part of the joint migration inversion output, being obtained by an operator-driven parametric inversion process. The potential of the proposed joint migration inversion algorithm is illustrated with numerical examples. [ABSTRACT FROM AUTHOR]

Predictive computer simulation of the temperature field control system of an induction heated object encounters difficulties associated with the nonlinearity of system on the one hand, and the time of calculation on the other hand, during numerical analysis of the magneto-thermal field of the object, especially in 3D. The paper presents a methodology for the fast simulation of temperature field for a completed induction heating system of calender rolls. The method of 3D calculations of rotating calender rolls with a moving web of wet paper can be connected easily with a simulation of the temperature field controller, for simulation of complex control systems. [ABSTRACT FROM AUTHOR]

As a propulsor with a good application prospect, the flapping foil has been a hot research topic in the past decade. Although the research results of flapping foils have been very abundant, the performance-influencing mechanism of flapping foils is still not perfect, and the research considering three-dimensional (3D) effects for engineering applications is still very limited. Based on the above considerations, a systematic and parametric analysis of a small aspect ratio flapping foil is conducted to correlate the influencing factors including angle of attack (AoA) characteristics and wake vortex on the propulsive efficiency. Three-dimensional numerical analyses of full-active and semi-active flapping foils are carried out in this paper, in which the former focuses on different heave amplitudes and pitch amplitudes, and the latter concentrates on different spring stiffnesses. The analysis covers the full range of advance coefficient, which starts around 0 and ends at a thrust drop of 0. Firstly, the influence of the maximum AoA (αmax) on the efficiency and thrust coefficient of these two kinds of flapping foils is analyzed. The results show that for the small aspect ratio flapping foil in this paper, regardless of the full-active or semi-active form, the peak efficiency as high as 75% for both generally appears around αmax = 0.2 rad, while the peak thrust coefficient of 0.5 occurs near αmax = 0.3 rad. Then, by analyzing the wake flow field, it is found that the lower efficiency of larger αmax working points is mainly due to the larger vortex dissipation loss, while the lower efficiency of smaller αmax working points is mainly due to the larger friction loss of the foil surface. Furthermore, the plumpness of different AoA curves is compared and analyzed. It was found that, unlike the results of full-active flapping foils, the shape of the AoA curve of semi-active flapping foils with different spring stiffnesses is similar, and the relationship with efficiency is not strictly corresponding. This study is expected to provide guidance on both academics and industries in relevant fields. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents and comments on the main experimental and numerical techniques in the considered paper. Several inaccuracies and problems in methodology are described, for example, description of the failure time and description of the dynamic tensile strength of glass (critical curve). The process of wave propagation reflection and interaction together with geometrical dispersion in bars is shown to present some disadvantages in analysis. [Copyright &y& Elsevier]

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It is our great pleasure and honor to present this special issue ofHeat Transfer Engineeringto highlight some of the research works presented at the ASME-ATI-UIT 2015 Conference on Thermal Energy Systems: Production, Storage, Utilization, and the Environment that took place on May 17–20, 2015, in Napoli, Italy. The conference was organized under the auspices of the American Society of Mechanical Engineers (ASME), Associazione Termotecnica Italiana (ATI), and Unione Italiana di Termofluidodinamica (UIT). [ABSTRACT FROM PUBLISHER]

Abstract: The high fidelity generalized method of cells (HFGMC) has been originally developed by as a micromechanical method for periodic multi-phase composite media. A computational implementation of the HFGMC equations has been proposed by to enhance numerical efficiency, still with direct reference to the HFGMC formulation. Later, the same computational implementation is recast as a new method called “finite volume direct averaging micromechanics” (FVDAM), starting by . The current discussion paper has two aims. The first is to show that the FVDAM is not a new method and that it has the same assumptions and identical governing equations as those originally derived by the HFGMC. The only difference is in the solution procedure where intermediate dependent variables, in the form of average displacements at the interfaces, are used instead of directly solving for the unknown micro-variables; the coefficients of the displacement polynomials. Thus, renaming the HFGMC micromodel to FVDAM has not been justified. In fact, () have shown that the same reduction of variables can be achieved by a simple static condensation carried out at the global system of equations instead of introducing intermediate variables. The second aim of this paper is to address misrepresentations in a recent discussion paper by the FVDAM authors claiming, in part, that the HFGMC method using parametric geometry of the subcells should follow their formulation (termed parametric FVDAM). We show that the latter is limited to an incomplete quadratic expansion of the displacement and an approximation in the form of a priori constant Jacobian of the parametric mapping. However, the HFGMC with arbitrary cell geometry, (), has been formulated in a direct and general manner, i.e. retaining the full quadratic expansion of the displacement together with the complete Jacobian. Thus, the parametric FVDAM is a special case of the parametric HFGMC, i.e. when the Jacobian is sampled and evaluated only at one point, namely the origin of the parametric coordinate system. The intended new contribution of to refined micromechanics and progressive damage has been completely ignored by the FVDAM-discussion paper. Therefore, in order to maintain scientific clarity, it is strongly advocated to preserve the original name of the HFGMC method, regardless of the different computational implementations used for solving the governing equations for both orthogonal and parametric geometries of the subcells. [Copyright &y& Elsevier]

Data from natural sources show counter-intuitive distribution patterns for the leading digits to the left of the decimal point and the digit 1 is observed more frequently than all other numbers. This pattern, which was first described by Newcomb and later confirmed by Benford, is used in financial and tax auditing to detect fraud. Deviations from the pattern indicate possible falsifications. Anesthesiology journals are affected not only by ghostwriting and plagiarism but also by counterfeiting. In the present study 20 publications in anesthesiology known to be falsified by an author were investigated for irregularities with respect to Benford's law using the χ-test and the Z-test. In the 20 retracted publications an average first-digit frequency of 243.1 (standard deviation SD ±118.2, range: 30-592) and an average second-digit frequency of 132.3 (SD ±72.2, range: 15-383) were found. The observed distribution of the first and second digits to the left of the decimal point differed significantly (p< 0.01) from the expected distribution described by Benford. Only the observed absolute frequencies for digits 3, 4 and 5 did not differ significantly from the expected values. In an analysis of each paper 17 out of 20 studies differed significantly from the expected value for the first digit and 18 out of 20 studies varied significantly from the expected value of the second digit. Only one paper did not vary significantly from expected values for the digits to the left of the decimal. For comparison, a meta-analysis using complex mathematical procedures was chosen as a control. The analysis showed a first-digit distribution consistent with the Benford distribution. Thus, the method used in the present study seems to be sensitive for detecting fraud. Additional statements of specificity cannot yet be made as this requires further analysis of data that is definitely not falsified. Future studies exploring conformity might help prevent falsified studies from being published. [ABSTRACT FROM AUTHOR]

The current researches on soil-pile interaction under combined action of axial and lateral loads are mainly focused on the short or middle-long piles in a homogeneous soil. The practice for design of piles subjected to both axial and lateral loads commonly considers the two loads separately. In this paper, a super-long pile group in stratified soils under both vertical and lateral loads and the pile-soil interaction with the pile cap in contact with ground are all simulated together by a three-dimensional nonlinear numerical model. The influence of lateral loading on the vertical pile stresses and bending moments is analyzed. In addition, the effect of vertical loading on the lateral pile response is also investigated. On the other hand, given the fact that the super-long pile group is relatively insufficient in resisting a large lateral load, the pile in shallow depth is sleeved to reduce the horizontal displacement. Using the sleeve, the lateral load is transferred onto the deeper soil mass. The results show that the sleeved super-long pile group proposed in this paper can reduce the horizontal displacement significantly and is feasible in practical applications. [ABSTRACT FROM AUTHOR]

Abstract: We present a model for the laminated composite plate problem based on the Reissner–Mindlin model and first-order lamination theory. The weak problem based on this model is solved with the finite element method using stabilized MITC (mixed interpolation of tensorial components) finite elements. Detailed a priori estimates are given for the mixed finite element formulation of the problem. Explicit bounds for the continuity and coercivity constants of the coupling terms are presented, thus refining earlier results. Furthermore, we present an application of the theory to the paper cockling problem and investigate the effect of boundary conditions on the small-scale deformation of the solution numerically. [Copyright &y& Elsevier]

• Multiple evaluation methodologies used in retinal vessel segmentation identified. • Published scores in 100 papers categorized by the methodology they are based on. • The scores are numerically adjusted to eliminate the biases for comparability. • A new baseline ranking of segmentation techniques provided. • The comparison of incomparable scores is an ongoing phenomenon in the literature. [Display omitted] In the last 15 years, the segmentation of vessels in retinal images has become an intensively researched problem in medical imaging, with hundreds of algorithms published. One of the de facto benchmarking data sets of vessel segmentation techniques is the DRIVE data set. Since DRIVE contains a predefined split of training and test images, the published performance results of the various segmentation techniques should provide a reliable ranking of the algorithms. Including more than 100 papers in the study, we performed a detailed numerical analysis of the coherence of the published performance scores. We found inconsistencies in the reported scores related to the use of the field of view (FoV), which has a significant impact on the performance scores. We attempted to eliminate the biases using numerical techniques to provide a more realistic picture of the state of the art. Based on the results, we have formulated several findings, most notably: despite the well-defined test set of DRIVE, most rankings in published papers are based on non-comparable figures; in contrast to the near-perfect accuracy scores reported in the literature, the highest accuracy score achieved to date is 0.9582 in the FoV region, which is 1% higher than that of human annotators. The methods we have developed for identifying and eliminating the evaluation biases can be easily applied to other domains where similar problems may arise. [ABSTRACT FROM AUTHOR]

Honeycomb paper core stretching is an important process in paper core manufacture because the performance and the quality of paperboard are greatly enhanced when the honeycomb hole is stretched to a regular hexagon structure. In view of the above, first the finite element method is used to compare the mechanical performances of honeycomb paperboards of different aperture ratios, and the aperture ratio, which has an important influence on the performance of the honeycomb paper, is explained. Next, a paper core stretching simulation is carried out by means of the dynamic software; thus the variation trend of the stretching force, the stretching speed, and the lateral shrinkage needed in paper core manufacture of different specifications can be obtained. This research can provide useful instruction in the actual manufacture of honeycomb paper core. [ABSTRACT FROM AUTHOR]

Abstract  A web is continuous, flexible materials such as paper, plastic film, metal foil, textiles, etc. Web wrinkle is a problem which plagues the process industries. Most webs are very thin and prone to buckle or wrinkle. The effects of wrinkling can range from compromised product quality to down time of a processing operation, leading to less profitability in the manufacturing operation. The web wrinkles which will be treated in this paper are those that can be affected by roller misalignment and friction characteristics between web and roller. In this paper, observation method is presented for paper-web wrinkling and the prediction model of wrinkling is proposed with experimental verifications. [ABSTRACT FROM AUTHOR]

Abstract: Comment on the paper “A class of methods based on non-polynomial spline functions for the solution of a special fourth-order boundary-value problems with engineering applications” in Applied Mathematics and Computation 174 (2006) 1169–1180. The paper considered a class of two-point boundary-value problems of the form where f(x) and g(x) are continuous on [a, b], and A i and B i (i =1,2) are finite real constants. Here we correct some mistake in derivation of non-polynomial spline, boundary formulas, truncation errors, convergence analysis and computational experiments. [Copyright &y& Elsevier]

Abstract: The present study was performed to explore a new approach to systematization of the management of paper-based clinical pathways by developing a new system requiring little capital investment. A new system was developed and incorporated into an existing network at a hospital with a paper-based clinical pathway management system. The effectiveness of this new system was examined by comparing the management efficiency of clinical pathways before and after its introduction, and by comparison of the new system with other such systems currently in place at other medical institutions with regard to efficiency. In addition, the acceptability of the system for other medical institutions was examined by providing free access to the software on the Internet. The development costs of the new system were low. Although the new system has been in place for more than 3 years, no problems have yet been encountered in either the existing network system or in the management system itself. The new system allows the processing of statistics and analysis of circulation or variance automatically, neither of which were possible in the original paper-based system. We provided open access to the system as free software on the Internet, and it has since been downloaded by many medical institutions and enterprises in Japan. This system is very useful for institutions where it is difficult to introduce expensive new systems for systematic management of clinical pathways, such as electronic medical records, because of problems regarding capital or system management, and it may also be useful in other countries. [Copyright &y& Elsevier]

Abstract: In this paper we will establish some new oscillation criteria for the second-order retarded differential equation of the formThe results obtained essentially improve and extend those of Džurina and Stavroulakis [Oscillation criteria for second-order delay differential equations, Appl. Math. Comput., 140 (2003) 445–453]. An open problem is proposed at the end of this paper. [Copyright &y& Elsevier]

Abstract: A model, using the finite element method (FEM), was developed for the analysis of the time and humidity-dependent stresses of paper webs at offset printing press conditions. The offset press was simplified to a flat thin moving web and its unit process steps were described by combinations of prescribed displacements, tractions and moisture ratios. Based on previous modelling and experimental findings, a convective hygro-viscoelastic model of the paper web was derived. The constitutive law and some of the boundary conditions were implemented as user-defined subroutines into commercial FEM software in a displacement-based framework. Some simulation examples were used to study the applicability of the proposed formulation in the analysis of web-fed offset printing at stationary conditions. The numerical stationary solutions converged rapidly and the model was robust for the investigated conditions. Incorporating effects from moisture, the numerical results show web tension profiles along the analysed model press comparable to those found by others from full-scale newsprint printing press trials. Effects of altered levels of the peripheral velocities of rollers, friction, web velocity, moisture and web properties on in-plane stresses and strains are presented. In order to exemplify the practical use of the model for runnability investigations, different analysed quantities obtained from the numerical solutions were related to web tension, web widening, misregister in multi-colour printing, sheet size analysis, conditions for web stability and traction conditions at drag rollers. [Copyright &y& Elsevier]

Abstract: The fundamentals of a new radiation model are described in this paper. The spatial and angular dependence of the radiation intensity are split in such a way that the radiation intensity is approximated by a linear combination of basis functions dependent only on the angular direction. The coefficients of the approximation are functions of the spatial coordinates. The spatial discretization is performed using the finite volume method and the angular discretization is based on the finite element method. This means that the basis functions are defined according to the criteria used in the finite element method. The step scheme was employed in the spatial discretization and bilinear basis functions were chosen for the angular discretization. The method may be applied to both grey and non-grey media, non-scattering and scattering media, simple and complex geometries. However, it is still in an early stage of development, and therefore it is applied in this paper to simple one-dimensional problems of radiative transfer in enclosures with grey, emitting-absorbing and scattering media. The results obtained show that the method gives good results for several benchmark problems with available analytical solutions, and converges to the exact solution as the grid is refined and the number of terms in the approximation increases. [Copyright &y& Elsevier]

Some errors exist in the above paper. [ABSTRACT FROM AUTHOR]

We show abstract versions for Banach couples of several limiting compact interpolation theorems established by Edmunds and Opic for couples of [ABSTRACT FROM AUTHOR]

The aim of this Authors’ Reply is to examine critically certain assertions by Logo in a Discussion and in two conference papers about a publication by Rozvany and Maute on a reliability based benchmark example [ABSTRACT FROM AUTHOR]