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Develops a linear programming model for integrated production planning based on the practice of a major Canadian steel making company. Considers the entire planning activity in the company as an integrated process involving a number of closely related sub‐functions, such as raw material purchasing, semi‐finished product purchasing and production, and capacity allocation, as well as finished product production and distribution. The mathematical programming model takes into account production costs, product throughput rates, customer demands, sales prices and facility capacities for optimal production planning. Presents a numerical example based on realistic system structure and practical planning data to illustrate the model. Computation results and analysis show that the integrated methodology is a feasible and practical approach for steel production planning.

As the transition away from lead‐containing solders gathers momentum, isotropic conducting adhesives (ICAs) are being considered as possible replacements for conventional SnPb solder in a range of applications. Consequently, the reliability of ICA joints is under scrutiny. The purpose of this paper is to report the effect of printed circuit board (PCB) and component finishes on the reliability of ICA joints.

Previous work by the authors identified a suitable test regime to generate relevant reliability data. In the present work, those tests are employed to investigate whether the finishes on the components and/or PCBs have any effect on the reliability of the ICA joints after exposure to damp heat conditions.

The effect of different finishes is found to be very adhesive material dependent. Two adhesives are studied, and for one material the joint reliability is relatively unaffected by changes in component or PCB surface finish. However, for the second material, and components with a high‐tin content‐plated finish, the joints display a less stable resistance. The surface finish on the PCB is found to have a smaller effect on joint reliability than the component finish, with results dependent on adhesive material type. Performance with one material exhibited little difference in reliability irrespective of the PCB surface finish. For the second material, the joint reliability performance with components having the electroless nickel/immersion gold finish, is not as good as that with components having the immersion tin or silver finishes.

The paper shows that surface finish is an important factor in determining the conductivity of ICA joints during exposure to the 85°C/85%RH environment. Systems containing tin are more prone to lose conductivity and, conversely, noble metal systems are more immune to degradation. This is a major concern as the industry is showing many signs that the component termination of choice will be pure tin.

The purpose of this paper is to introduce a new class of surface finishes as an alternative to current final surface finishes.

This new finish utilises nanotechnology and is based on a new formulation of the “organic metal” (OM).

The final surface finish is an approximately 50 nm thin permanent layer, consisting of a complex between the OM and silver (Ag). Panels finished with OrmeSTAR™ Ultra show excellent solderability in spite of a low‐layer thickness and therefore offer significant advantages over existing surface finishes.

This new finish has proven to be a competitive alternative to current final finishes with excellent properties for soldering applications. The new nanotechnology can also significantly improve the environmental and economical consequences of solderable surface finishing.

The formulation of industrial finishes to protect and improve the appearance of mass‐produced articles has become an increasingly complicated technique with the growing range of materials flow available. In this article Mr. Macrae, after discussing surface preparation and application methods, describes the formulation and performances of stoving enamels, cold‐curing finishes and air‐drying finishes. He concludes that even with the number of resins available today there is still much room for improvement.

Three-dimensional (3D) printed parts usually have poor surface quality due to layer manufacturing’s “stair casing/stair-stepping”. So post-processing is typically needed to enhance its capabilities to be used in closed tolerance applications. This study aims to examine abrasive flow finishing for 3D printed polylactic acid (PLA) parts.

A new eco-friendly abrasive flow machining media (EFAFM) was developed, using paper pulp as a base material, waste vegetable oil as a liquid synthesizer and natural additives such as glycine to finish 3D printed parts. Characterization of the media was conducted through thermogravimetric analysis and Fourier transform infrared spectroscopy. PLA crescent prism parts were produced via fused deposition modelling (FDM) and finished using AFM, with experiments designed using central composite design (CCD). The impact of process parameters, including media viscosity, extrusion pressure, layer thickness and finishing time, on percentage improvement in surface roughness (%ΔRa) and material removal rate were analysed. Artificial neural network (ANN) and improved grey wolf optimizer (IGWO) were used for data modelling and optimization, respectively.

The abrasive media developed was effective for finishing FDM printed parts using AFM, with SEM images and 3D surface profile showing a significant improvement in surface topography. Optimal solutions were obtained using the ANN-IGWO approach. EFAFM was found to be a promising method for improving finishing quality on FDM 3D printed parts.

The present study is focused on finishing FDM printed crescent prism parts using AFM. Future research may be done on more complex shapes and could explore the impact of different materials, such as thermoplastics and composites for different applications. Also, implication of other techniques, such as chemical vapour smoothing, mechanical polishing may be explored.

In the biomedical field, the use of 3D printing has revolutionized the way in which medical devices, implants and prosthetics are designed and manufactured. The biodegradable and biocompatible properties of PLA make it an ideal material for use in biomedical applications, such as the fabrication of surgical guides, dental models and tissue engineering scaffolds. The ability to finish PLA 3D printed parts using AFM can improve their biocompatibility, making them more suitable for use in the human body. The improved surface quality of 3D printed parts can also facilitate their sterilization, which is critical in the biomedical field.

The use of eco-friendly abrasive flow finishing for 3D printed parts can have a positive impact on the environment by reducing waste and promoting sustainable manufacturing practices. Additionally, it can improve the quality and functionality of 3D printed products, leading to better performance and longer lifespans. This can have broader economic and societal benefits.

This AFM media constituents are paper pulp, waste vegetable oil, silicon carbide as abrasive and the mixture of “Aloe Barbadensis Mill” – “Cyamopsis Tetragonoloba” powder and glycine. This media was then used to finish 3D printed PLA crescent prism parts. The study also used an IGWO to optimize experimental data that had been modelled using an ANN.

This study aims to explore the incorporation of starch nanoparticles (SNPs) in cross-linking formulation of cotton fabrics to see their impact on fabric performance like tensile strength, dry wrinkle recovery angles, elongation at break, degree of whiteness and increase in weight as well as durability.

SNPs of size around 80-100 nm were successfully prepared from native maize starch by Nano precipitation technique and confirmed instrumentally by scanning electron microscope (SEM), transmittance electron microscope (TEM), Fourier transformer infrared (FTIR) spectroscopy and particle size analyzer. The latter were incorporated in cross-linking formulation of cotton fabrics encompassing different concentrations of citric acid and sodium hypophosphite at different curing time and temperature in 100 ml distilled water to a wet pickup of ca. 85 per cent. The fabric samples were dried for 3 min at 85°C and cured at specified temperatures for a specified time intervals in thermo fixing oven according to pad-dry-cure method.

FTIR spectra and SEM micrograph signified the chemical structure and surface morphology of cotton fabric before and after finishing in absence and presence of SNPs. Cotton fabric samples finished in presence of SNPs showed a higher tensile strength, elongation at break, comparable dry wrinkle recovery angles and degree of whiteness than that finished in their absence. On the other hand, the enhancement in the aforementioned performance reflects the positive impact of incorporation of SNPs in textile finishing especially with strength properties; which are one of the important requirements for industrial fabrics that can be used widely in heavy-duty applications.

SNPs with its booming effect with respect to biodegradability, reactivity and higher surface area can be used as a novel reinforcement permanent finish for cotton fabrics instead of more hazardous materials likes poly acrylate and monomeric compounds.

As SNPs biopolymers is one of the important reinforcement agents, so it was expected that it would minimize the great loss in strength properties during easy-care cotton finishing and improve the fabric performance.

The novelty addressed here is undertaken with a view to remediate some of the serious defects of easy-care cotton fabrics using poly carboxylic acids; especially with the great loss in strength properties by virtue of using SNPs as a permanent finish. Besides, to the authors’ knowledge, there is no published work so far concerning the use of SNPs as an innovative base for production of easy-care finished cotton textiles with high performance.

The purpose of this paper is to review the various pre-processing and post-processing approaches used to ameliorate the surface characteristics of fused deposition modelling (FDM)-based acrylonitrile butadiene styrene (ABS) prototypes. FDM being simple and versatile additive manufacturing technique has a calibre to comply with present need of tailor-made and cost-effective products with low cycle time. But the poor surface finish and dimensional accuracy are the primary hurdles ahead the implementation of FDM for rapid casting and tooling applications.

The consequences and scope of FDM pre-processing and post-processing parameters have been studied independently. The comprehensive study includes dominance, limitations, validity and reach of various techniques embraced to improve surface characteristics of ABS parts. The replicas of hip implant are fabricated by maintaining the optimum pre-processing parameters as reviewed, and a case study has been executed to evaluate the capability of vapour smoothing process to enhance surface finish.

The pre-processing techniques are quite deficient when different geometries are required to be manufactured within limited time and required range of surface finish and accuracy. The post-processing techniques of surface finishing, being effective disturbs the dimensional stability and mechanical strength of parts thus incapacitates them for specific applications. The major challenge for FDM is the development of precise, automatic and controlled mass finishing techniques with low cost and time.

The research assessed the feasibility of vapour smoothing technique for surface finishing which can make consistent castings of customized implants at low cost and shorter lead times.

The extensive research regarding surface finish and dimensional accuracy of FDM parts has been collected, and inferences made by study have been used to fabricate replicas to further examine advanced finishing technique of vapour smoothing.

This paper aims to assess the relationships amongst the tearing strength of fabrics after each chemical processing stage and after finishing of plain-woven cotton fabric. An effort has been made to study the effect of different finishing chemicals (tear improver) and their different concentrations on the high-density fabric tear strength and its sub-component with respect to the co-efficient of friction value of yarns for all the fabric samples. It also aims to establish a statistical model for prediction of tear strength with identified parameters as yarn–yarn friction co-efficient, yarn pullout force and single yarn strength.

In case of woven fabrics, it cannot be assumed that only yarn friction plays the role in deciding fabric-tearing strength. Whether the static or kinetic frictions need to be considered or the linear or capstan frictions have to be analyzed, to incorporate the results of friction analysis in the tearing behavior, need to be assessed. In the present work through a fabrication of yarn–yarn friction measurement, under a synchronized slow speed as that of actual fabric tearing (50 mm/min), has been carried out. After each wet processing stage, surface characteristics of yarns have been changed. Surface of yarns becomes smoother after finishing and rough after dyeing, which affects the co-efficient of friction of yarns, accordingly.

After each wet processing stage, the surface characteristics of yarns are changed. Surface structure of yarns becomes smooth after finishing and rough after dyeing, which affects the co-efficient of friction of yarns. For all the fabrics, the weft-way tearing strength is always higher than warp-way tearing strength. It is also observed that yarn pullout force is not the only responsible factor for tearing strength of such fabric. It is because of the combined action of yarn–yarn friction, yarn pullout force and single yarn strength for a given structure.

A more extensive investigation with respect to concentration as well as further variety of chemicals requires to be identified for the optimum concentration level for each chemical. A mathematical model based on the three parameters as yarn–yarn co-efficient of friction, yarn pullout force and yarn strength for all woven fabric structure to achieve optimum strength level has been established which could be further extended for each fabric structures.

The problem has been identified from the day-to-day exercise of the commercial textile industry. The whole of the sample preparations have been done in the industry by using commercial machines under standard industrial conditions. The findings have been discussed and suitably introduced in the industry.

The whole of this paper has been unique in idea origination, sample preparation and execution of tests. The findings are very important for the researchers as well as for textile industry.

The purpose of this paper is to identify, analyze and discuss floor finishes used in health-care facilities and their selection criteria in the form of advantages and disadvantages. The authors also identify the top three health-care floor finishes and selection criteria based on the literature review results. Although flooring materials have a considerable impact on the life-cycle cost and indoor environment of health-care facilities, what criteria may be used for such flooring choices is not thoroughly studied.

The authors performed a systematic review of the literature on certain flooring systems currently used in health-care facilities and the criteria applied for their selection. Peer-reviewed studies and articles published after Year 2000 consistent with the research design were included.

Sixteen different selection criteria that influence the choice of floor finishes in health-care facilities were determined and discussed. The results show that the top three-floor finish materials preferred in health-care facilities are sheet vinyl, rubber and carpet, and the top three selection criteria for floor finishes are indoor air quality, patient safety and infection control.

The results of this study will assist building owners, architects and interior designers with implementing an informed design decision-making process, particularly in relation to floor finish selection. The findings will also provide guidance to floor finish manufacturers to improve their products based on facility managers’ preferences.

Glutaraldehyde is chosen as a novel non-formaldehyde durable press finish for cotton fabrics in this investigation. The optimum technique conditions and influences of glutaraldehyde concentration and catalysts, pH value, and curing conditions for the properties of the finished fabric have been investigated in detail. The finished fabric achieves the best performance with a pH value in the range of 4 to 4.5 for the glutaraldehyde finishing bath, magnesium chloride as the catalyst, and curing conditions of 160oC for 3 minutes. In addition, in contrast to low formaldehyde resin and non-formaldehyde finishers sold in the market, the wrinkle recovery angle of the fabric finished with glutaraldehyde is better than that finished with FREEREZ NFR (DHDMI), but not as satisfactory as that finished with FREEREZ 880 (low formaldehyde 2D). However, its strength is greater than the fabric finished with FREEREZ 880, but less so than that finished with FREEREZ NFR.