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This paper traces the evolution of objective measurement of textile hand and comfort from Pierce through modern methodology and approaches. Special emphasis is given to discuss the contribution of the Kawabata Evaluation System (KES) towards advancing the state of objective measurement. Laboratory case studies are used to show how data generated by the KES and other instruments can be integrated into a comprehensive approach that attempts to explain human comfort response to garment wear in terms of fabric mechanical, surface and heat and moisture transfer properties.

The purpose of this paper is to examine several calibration techniques that have been developed to determine the discrete element method (DEM) parameters for slow and rapid unconfined flow of granular conical pile formation. This paper also aims to discuss some of the methods currently employed to scale particle properties to reduce computational resources and time to solve large DEM models.

DEM models have been calibrated against simple bench‐scale experimental results to examine the validity of selected parameters for the contact, material and mechanical models to simulate the dynamic and static behaviour of cohesionless polyethylene pellets. Methods to determine quantifiable single particle parameters such as static friction and the coefficient of restitution have been highlighted. Numerical and experimental granular pile formation has been investigated using different slumping and pouring techniques to examine the dependency of the type of flow mechanism on the DEM parameters.

The proposed methods can provide cost effective and simple techniques to determine suitable input parameters for DEM models. Rolling friction and particle shape representation has shown to have a significant influence on the bulk flow characteristics via a sensitivity analysis and needs to be accessed based on the environmental conditions.

This paper describes several effective known and novel methodologies to characterise granular materials that are needed to accurately model granular flow using the DEM to provide valuable quantitative data. For the DEM to be a viable predictive tool in industrial applications which often contain huge quantities of particles with random particle shapes and irregular properties, quick and validated techniques to “tune” DEM models are necessary.

The purpose of this paper is to present a latest update on halogen‐free base materials that are lead‐free compatible and have enhanced electrical properties.

Numerous halogen‐free flame retardants are screened in laboratory conditions for a wide arrange of properties. Once suitable candidates are found, they are compounded and processed into copper‐clad laminates and a wide variety of properties are tested.

Several formulations are found that are lead‐free compatible and that has enhanced electrical properties. Surprisingly, some thermal properties are found to be superior to traditionally halogenated laminates.

The research here only presents the halogen‐free properties of a bare, unpopulated printed wiring board with no build up of inner layers and devoid of solder mask. Further work needs to be done on full circuit assemblies to properly evaluate the impact of removing halogens from interconnecting packages.

The paper details the material property differences between various halogen‐free materials as compared to halogenated materials. A method to model composite properties is also discussed.

Metal‐based powder systems for selective laser sintering applications provide flexibility in the part geometry and promise a high quality profile regarding their material technologies characteristic. In this field of application, materials have to fulfil high demands on their properties already in the conceptual phase of development. For the integration of selective laser sintered parts into the development process, determining their properties using material engineering methods is absolutely essential. This paper concerns with the methods of material analysis, the particular material properties of sintered metals and finally with the description of the properties of the powder systems EOS DirectSteel 20 and 3D Laser Form ST100 in comparison to conventional materials used in automotive engines and power trains.

The purpose of this paper is to characterize the material properties of carbon fiber polyamide composite (CFPC) used in a 3D rapid prototyping process based upon selective laser sintering (SLS) and demonstrate that the SLS process introduces a bias in the micro‐fiber orientation such that the CFPC solid is an orthotropic structural material.

Material coupons for tensile tests from each of the orthogonal planes are created using the SLS process. After tensile testing, the coupons are examined under scanning electron microscopy to verify the micro‐fiber orientation bias. A complex 3D structure developed utilizing the CFPC material is subjected to modal testing to extract the natural frequencies. These frequencies are compared to predictive numerical analysis results from computer‐aided engineering (CAE) software to validate the coupon test results.

This paper proves that the CFPC solid material is orthotropic after the SLS process and that the process itself creates bias in the micro‐fiber orientation. Predictions of natural frequencies from CAE software for a complex 3D structure created from CFPC are within 2 percent of the actual natural frequencies determined during modal testing.

The paper has determined the tensile material characteristics of solid CFPC correcting the original material data sheet information which lists the solid CFPC as isotropic with much stronger tensile characteristics. It has also provided evidence of the bias that SLS introduces to embedded micro‐fibers during the rapid‐prototyping process.

The paper deals with experimental work on determining the material characteristics of a relatively new composite material for which very little test data exists in literature. In particular, an original contribution is demonstration of the micro‐fiber orientation bias introduced by the SLS process.

The purpose of this paper is to present an introductory overview of graphene, its properties and potential for use in interconnection applications.

This short paper has been written to provide those working on interconnect applications in the PCB and semiconductor sectors with an introductory overview of graphene and its properties. This has been achieved through a review of the published literature.

Graphene has unique properties that make it of interest for potential use in interconnection applications and, in the last few years, some workers have begun to demonstrate the possibilities for this novel material.

This is a short introductory paper and only gives a limited overview of graphene, its properties and applications. It is based on information published in the literature and, while some examples are cited, it does not represent a comprehensive review.

The paper seeks to give an overview of what graphene is and how its unique properties offer potential for interconnection related applications. References provide the opportunity to investigate the properties of this material in more detail.

Investigations over new types of materials as a potential power source for different types of devices were raised dramatically in the last few years. It is connected especially with global needs and that most of the devices in our world need electricity to work. In this paper, an investigation on magnetoelectric effect in the magnetostrictive-piezoelectric composite material is presented.

An author's research setup for investigation of magnetoelectric effect in the developed novel material was prepared. The new composite material was made of magnetostrictive particles of Terfenol-D and lead zirconium titanate (PZT) material.

Obtained results show that changes in an electric voltage output from the prepared material are highly dependent on the changes in external magnetic field. It was found out that rate of changes of magnetic field around composite material is one of the most important factors which has influence on the magnetoelectric effect. Taking into account the obtained results, it was proven that prepared hybrid material shows magnetoelectric effect in the case of work in alternating magnetic field.

This phenomenon might be used in a field of energy harvesting as potential power source for devices with low power consumption. Moreover, this new material gives an opportunity to be used as an additional gauge for determination of deformation or crack propagation in the samples during fatigue tests.

TURBINE disks of jet propulsion units operate under conditions of considerable complexity for which steam turbine practice and experience afford little assistance in matters of calculation and design.

The purpose of this paper is to study the effects of water immersion‐freeze‐thaw treatment on the physical properties, flexural strength (FS) and morphology of wood‐polypropylene composites containing pigments.

Wood‐polypropylene composites containing brown, green and grey pigments were compounded in a conical twin‐screw extruder. A composite manufactured without any pigment addition was used as a reference. The amount of pelletized wood, polypropylene and coupling agent (MAPP) was kept constant. The moisture content, thickness swelling (TS), FS and surface colour of the composites were measured before and after water immersion‐freeze‐thaw cycling. Scanning electron microscopy (SEM) was used to study the morphology of the composites.

FS and dimensional stability were reduced after exposure to water immersion‐freeze‐thaw cycling for all composites. The surface properties (colour and roughness) of the composites also changed after exposure to water immersion‐freeze‐thaw cycling. The degree of change depended on the presence of pigment and the type of polypropylene (neat or recycled), however.

This study is a part of an ongoing study on weathering of wood‐polymer composites (WPC) containing different additives. The results of this study were obtained from accelerated laboratory experiments.

Inorganic pigments are widely used as additives in plastics, because they have an excellent UV absorption, good IR‐reflective properties and heat stability. The research revealed that metal‐containing pigments had an effect on degradation in quality of wood‐polypropylene composites exposed to water immersion‐freeze‐thaw cyclic treatment. The addition of metal‐containing pigments to composite formulation resulted in a higher susceptibility of wood‐polypropylene composites to water absorption, and as a consequence to a higher drop of FS compared to composites made without pigment. The polymer matrix plays an important role in the protection of WPC against weathering.

This paper will help in understanding possible problems in the durability of wood‐polypropylene composites compounded with metal‐based pigments when they are exposed to water immersion‐freeze‐thaw cyclic treatment.

To cover the main contributions and developments in solar thermal collectors through focusing on materials, heat transfer characteristics and manufacturing challenges.

A range of published papers and internet research including research work on various solar thermal collectors (flat plate, evacuated tubes, and heat pipe tube) were used. Evaluation of solar collectors performance is critiqued to aid solar technologies make the transition into a specific dominant solar collector. The sources are sorted into sections: finding an academic job, general advice, teaching, research and publishing, tenure and organizations.

Provides information about types of solar thermal collectors, indicating what can be added by using evacuated tube collectors instead of flat plate collectors and what can be added by using heat pipe collectors instead of evacuated tubes.

Focusing only on three types of solar thermal collectors (flat plate, evacuated tubes, and heat pipe tube).

Useful source of information for consultancy and impartial advice for graduate students planning to do research in solar thermal technologies.

This paper fulfils identified information about materials and heat transfer properties of materials and manufacturing challenges of these three solar thermal collectors.