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The NIRVANA project is concerned with the development of a nonoscillatory, integrally reconstructed, volume‐averaged numerical advection scheme. The conservative, flux‐based finite‐volume algorithm is built on an explicit, single‐step, forward‐in‐time update of the cell‐average variable, without restrictions on the size of the time‐step. There are similarities with semi‐Lagrangian schemes; a major difference is the introduction of a discrete integral variable, guaranteeing conservation. The crucial step is the interpolation of this variable, which is used in the calculation of the fluxes; the (analytic) derivative of the interpolant then gives sub‐cell behaviour of the advected variable. In this paper, basic principles are described, using the simplest possible conditions: pure one‐dimensional advection at constant velocity on a uniform grid. Piecewise Nth‐degree polynomial interpolation of the discrete integral variable leads to an Nth‐order advection scheme, in both space and time. Nonoscillatory results correspond to convexity preservation in the integrated variable, leading naturally to a large‐Δt generalisation of the universal limited. More restrictive TVD constraints are also extended to large Δt. Automatic compressive enhancement of step‐like profiles can be achieved without exciting “stair‐casing”. One‐dimensional simulations are shown for a number of different interpolations. In particular, convexity‐limited cubic‐spline and higher‐order polynomial schemes give very sharp, nonoscillatory results at any Courant number, without clipping of extrema. Some practical generalisations are briefly discussed.

The purpose of this paper is to understand the emergence of digital reformatting as a technique for preserving information within the cultural heritage preservation community by reviewing historical trends in modern preservation research.

This paper analyzes secondary sources, reviews and historical texts to identify trends in the intellectual and technological histories of preservation research, beginning with the first applications of the scientific method to combating book decay in the early nineteenth to the emergence of digitization techniques in the late twentieth and early twenty-first centuries.

This paper identifies five major historical periods in the development of preservation knowledge: the early experimental era; era of microfilm experimentation; era of professionalization; era of digital library research; and the era of digital reformatting and mass digitization; and identifies three major trends in its development: empirical inquiry, standardization and centralization.

Findings reflect broad trends in the field of preservation, primarily in a United States context and are limited to the modern era of preservation research.

This paper's broad historical overview provides a reference for preservation professionals and students in library science or archives programs. Identifying historical trends enables practitioners to critically examine their own preservation techniques and make better decisions when adopting and using new preservation technologies.

This paper provides a unique perspective on the history of preservation knowledge that synthesizes existing historical research in order to identify periods and trends that enable a clearer understanding of digital reformatting in its historical emergence.

Auxetic structures are one type of mechanical meta-materials mainly used for energy absorption applications because of their unique negative Poisson’s ratio. This study is focused on numerical and experimental investigations of fused deposition modeling (FDM) fabricated re-entrant auxetic structures of acrylonitrile butadiene styrene (ABS) and poly-lactic acid (PLA) materials under compressive loading. Influence of geometric parameters, namely, re-entrant angle, height and arm-length on strength, stiffness and specific energy absorption (SEA) of auxetic structures under compressive loading. Optimization of significant parameters is also performed to maximize these responses and minimize weight and time of fabrication. Further, efforts have also been made to develop predictive models for strength, stiffness and SEA of auxetic structures.

A full factorial design of experiment is used for planning experiments. Auxetic structures of ABS and PLA are fabricated by FDM technique of additive manufacturing within the constrained range of geometric parameters. Analysis of variance is performed to identify the influence of geometric parameters on responses. To optimize the geometric parameters Gray relational analysis is used. Deformation of auxetic structures is studied under compressive loading. A numerical investigation is also performed by building nonlinear finite element models of auxetic structures.

From the analysis of results, it is found that re-entrant angle, height and arm-length with their interactions are significant parameters influencing responses, namely, strength, stiffness and SEA of the auxetic structures of ABS and PLA materials. Based on the analysis, statistical nonlinear quadratic models are developed to predict these responses. Optimal configurations of auxetic structure of ABS and PLA are determined to maximize strength, stiffness, SEA and minimize weight and time of fabrication. From the study of deformation of auxetic structures, it is found that ABS structures have higher energy absorption, whereas PLA structures have better stiffness. Results of finite element analysis (FEA) are found in good agreement with experimental results.

The present study is limited to re-entrant type of auxetic structures of ABS and PLA materials only under compressive loading. Also, results from the present study are valid within the selected range of geometric parameters. The findings of the present study are useful in maximizing strength, stiffness and SEA of auxetic structures that have wide applications in the automotive, aerospace, sports and marine sector.

No literature is available on studying the influence of geometric parameters, namely, re-entrant angle, height and arm-length of auxetic structure on strength, stiffness and SEA under compressive loading. Also, a comparative study of feedstock materials, namely, ABS and PLA, is also not reported. The present work attempts to fulfill the above research gaps.

The purpose of the work is development a novel of hydro-vibration technology for the formation of hats from fabrics, which will expand the functionalities of application of various fabrics.

The work is based on a novel technology of forming hats from different fabrics with the use of liquid-active working environment (LAWE). This hydro-vibration technology is characterized by high efficiency, productivity, manufacturability and potential opportunities when compared to existing technologies. This allows expanding its range of applications and increase functionality.

In the article, hydro-vibration technology is developed for the formation of hats from fabrics. As a result of the experiment, regression dependences of the shape stability coefficient on the formation factors having a close correlation were obtained. The performed optimization allowed determining the optimal values of technological parameters of the vibroforming process from fabrics: LAWE pressure 0.26 MPa, vibration frequency LAWE 4.3 Hz, forming time 74 s.

The use of developed hydro-vibration technology has great practical significance in the textile industry. This technology increases labor productivity and reduces the cost of production of hats due to its high efficiency. Increased efficiency is provided by the use of special equipment, methods and optimal parameters of the hats formation. With sufficient refinement, the developed technology can be applied to other technological processes.

Originality of the work is using liquid-actin working environment at vibroforming of heads of headdresses from fabrics. It is determined that the use of LAWE is effective in the formation of hats. To ensure maximum plasticization of textile fibers in the fabric of the part and increase the force field, it is developed a novel hydro-vibration technology of forming the heads of hats from fabrics.