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1 – 10 of over 161000The purpose of this paper is to research the ecological properties of building materials used in some traditional buildings in Turkey and discuss the environmental benefits…
Abstract
Purpose
The purpose of this paper is to research the ecological properties of building materials used in some traditional buildings in Turkey and discuss the environmental benefits thereof.
Design/methodology/approach
Building materials used in some traditional buildings are investigated by a field study in the selected area. In this investigation, after the usage aims of the building materials are explained, the ecological properties and environmental benefits are discussed.
Findings
According to the results of the study, it is found that these materials being obtained from totally natural, local and renewable resources have source‐efficient and energy‐efficient features. They have significant ecological characteristics since they are easily recyclable and re‐usable, utilize agricultural wastes and do not produce any wastes.
Research limitations/implications
In almost every part of Turkey, there exist a large number of traditional buildings with ecological properties which were built at various times in history. However, it is impossible to give examples from each one of them in this study. Therefore, this study is designed to cover the buildings located at the rural area of province Kirklareli, Thrace zone. In further studies, it is possible to compare them with building samples from other region of Turkey and the World.
Originality/value
This study researches the ecological properties of building materials used in some traditional buildings. It is considered that these data would provide guidance for the building designs of today. In the rural areas where population increase rates are not so high, it is possible to use such materials for the buildings. A widespread use of these materials will prevent the environmental problems that arise out of buildings from getting higher in Turkey and in the world.
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Mario Chong, Juan G. Lazo Lazo, Maria Cristina Pereda and Juan Manuel Machuca De Pina
The purpose of this paper is to improve disaster management models, have an optimal distribution of assets, reduce human suffering in a crisis and find a good solution for…
Abstract
Purpose
The purpose of this paper is to improve disaster management models, have an optimal distribution of assets, reduce human suffering in a crisis and find a good solution for warehouse locations, distribution points, inventory levels and costs, considering the uncertainty of a wide range of variables, to serve as a support model for decision making in real situations.
Design/methodology/approach
A model is developed based on the recent models. It includes structured and non-structured data (historical knowledge) from a humanitarian perspective. This model considers the uncertainty in a landslide and flood area and it is applied in a representative Peruvian city.
Findings
The proposed model can be used to determine humanitarian aid supply and its distribution with uncertainty, regarding the affected population and its resilience. This model presents a different point of view from the efficiency of the logistics perspective, to identify the level of trust between all the stakeholders (public, private and academic). The finding provides a new insight in disaster management to cover the gap between applied research and human behavior in crisis.
Research limitations/implications
In this study the access of reliable information is limited.
Practical implications
This paper provides an operation model with uncertainty in a humanitarian crisis and a decision-making tool with some recommendation for further public policies.
Originality/value
This study presents a model for decision makers in a low-income zone and highlights the importance of preparedness in the humanitarian system. This paper expands the discussion of how the mathematical models and human behaviors interact with different perspectives in a humanitarian crisis.
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WEAR is one of the major ways by which a material part ceases to be useful, others are corrosion, obsolescence and breakage. It is the consequence of relative motion and in…
Abstract
WEAR is one of the major ways by which a material part ceases to be useful, others are corrosion, obsolescence and breakage. It is the consequence of relative motion and in industrial plant and equipment it has always been accepted as inevitable that it should lead to heavy expenditure for maintenance and replacement. Historically, wear is a well established fact, yet our knowledge of the technology is extremely limited. It has become a way of life that we compensate for wear when it no longer can be tolerated, yet need this be so? This article examines the problem, and primarily from the unlubricated point of view, describes the various types of wear and the way material selection or modification can be used to limit wear.
Xiong Liang, Bing Li, Xiaoyu Wu, Hongyan Shi, Kun Zeng and Yatao Wang
The purpose of this paper is to present a method for ultrasonically molding polymer powder in a micro plastic part mold. In the method, a printed circuit board (PCB) in which…
Abstract
Purpose
The purpose of this paper is to present a method for ultrasonically molding polymer powder in a micro plastic part mold. In the method, a printed circuit board (PCB) in which micro‐hole arrays are drilled is used as a micro cavity insert. With the utilization of ultrasonic vibration, the polymer powder, which is prefilled and compacted in a micro cavity, mutually generates great sliding friction heat so as to be rapidly plasticized and molded.
Design/methodology/approach
Micro carbide drill bits of which the diameters are 100.0 μm, 150.0 μm and 200.0 μm, respectively, are used for drilling the PCB to form a micro‐hole array insert. Next, two kinds of various ultra‐high molecule weight polyethylene (UHMW‐PE) powder with various grain diameters are directly filled into a charging barrel and a mold cavity with the micro‐hole array insert. Proper process parameters are set on ultrasonic plasticizing and molding equipment so that a molding test can be performed. The melt of UHMW‐PE can be rapidly filled into the cavity. Finally, micro‐column array plastic parts are successfully prepared.
Findings
The micro‐hole array PCB is a mold insert which is quite applicable for the ultrasonic molding of the powder in the mold. When a molding material is the coarse UHMW‐PE powder with the grain diameter of about 350 μm, the diameter replication rates of the micro‐column array plastic parts become good in order with the increased micro‐hole diameter of the PCB. When the fine UHMW‐PE powder with the grain diameter of about 80 μm is adopted, the diameter replication rates of the micro‐column array plastic parts become good in order with the decreased micro‐hole diameter of the PCB.
Originality/value
In this paper, the micro‐column array plastic parts with good replicability are successfully prepared by a technique for ultrasonically plasticizing and molding in the cavity. The technique can be applied to the fields of medical treatment, communication, optics, chemistry and so on, such as biological micro needle arrays, micro biological chips, optical memories, and micro chemical reaction chips.
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Pankaj V Katariya and Subrata Kumar Panda
The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate…
Abstract
Purpose
The purpose of this paper is to develop a general mathematical model for laminated curved structure of different geometries using higher-order shear deformation theory to evaluate in-plane and out of plane shear stress and strains correctly. Subsequently, the model has to be validated by comparing the responses with developed simulation model (ANSYS) as well as available published literature. It is also proposed to analyse thermal buckling load parameter of laminated structures using Green–Lagrange type non-linear strains for excess thermal distortion under uniform temperature loading.
Design/methodology/approach
Laminated structures known for their flexibility as compared to conventional material and the deformation behaviour are greatly affected due to combined thermal/aerodynamic environment. The vibration/buckling behaviour of shell structures are very different than that of the plate structures due to their curvature effect. To model the exact behaviour of laminated structures mathematically, a general mathematical model is developed for laminated shell geometries. The responses are evaluated numerically using a finite element model-based computer code developed in MATLAB environment. Subsequently, a simulation model has been developed in ANSYS using ANSYS parametric design language code to evaluate the responses.
Findings
Vibration and thermal buckling responses of laminated composite curved panels have been obtained based on proposed model through a customised computer code in MATLAB environment and ANSYS simulation model using ANSYS parametric design language code. The convergence behaviour are tested and compared with those available in published literature and ANSYS results. Finally, the investigation has been extended to examine the effect of different parameters (thickness ratios, curvature ratios, modular ratios, number of layers and support conditions) on the free vibration and thermal buckling responses of laminated curved structures.
Practical implications
The present paper intends to give sufficient amount of numerical experimentation, which may lead to help in designing of finished product made up of laminated composites. Most of the aerospace, space research and defence organisation intend to develop low cost and high durable products for real hazard conditions by taking combined loading and environmental conditions. Further, case studies might lead to a lighter design of the laminated composite panels used in high-performance systems, where the weight reduction is the major parameter, such as aerospace, space craft and missile structures.
Originality/value
In this analysis, the geometrical distortion due to temperature is being introduced through Green–Lagrange sense in the framework of higher-order shear deformation theory for different types of laminated shells (cylindrical/spherical/hyperboloid/elliptical). A simulation-based model is developed using ANSYS parametric design language in ANSYS environment for different geometries and loading condition and compared with the numerical model.
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Kati Kokko, Hanna Harjunpää, Anna‐Maija Haltia, Pekka Heino and Minna Kellomäki
The purpose of this paper is to study epoxy and parylene C‐coated samples. These coatings are used to protect the electronic devices from harsh environments. The effect of these…
Abstract
Purpose
The purpose of this paper is to study epoxy and parylene C‐coated samples. These coatings are used to protect the electronic devices from harsh environments. The effect of these conformal coatings on electronics reliability is considered.
Design/methodology/approach
Epoxy coating is applied using dip coating and parylene C is applied with the vapour deposition polymerisation method. Test chip used is joined using flip‐chip technology and an anisotropically conductive adhesive. Reliability of the test samples is evaluated in a constant humidity test, where test conditions are 85°C and 85%RH. The test lasts 4,000 h. Failure analysis is carried out by cross‐sectioning failed samples and using scanning electron microscopy for closer analysis.
Findings
The results show variation in the reliability of adhesive joints with different conformal coating materials. Failure analysis highlights explicit failure mechanisms. Adhesion testing is also carried out on the test samples after constant humidity testing. The results of these reliability tests indicate clearly that parylene C is a more reliable choice of conformal coating than epoxy.
Originality/value
The paper shows the influence of certain conformal coatings on the reliability of adhesive flip‐chip joints. In medical applications, reliability plays an important role.
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David Palousek, Martin Kocica, Libor Pantelejev, Lenka Klakurkova, Ladislav Celko, Daniel Koutny and Jozef Kaiser
Materials with a high thermal conductivity, such as Cu-alloys hold the most interest to the plastic moulding industry. Additive manufacturing (AM), especially selective laser…
Abstract
Purpose
Materials with a high thermal conductivity, such as Cu-alloys hold the most interest to the plastic moulding industry. Additive manufacturing (AM), especially selective laser melting (SLM) of metals, allows the production of parts with complicated internal cooling and increased production efficiency. The portfolio of alloys for metal AM is limited and still missing process parameters for the processing of copper alloys. This paper aims to preview the process parameters of high-strength alloy Cu7.2Ni1.8Si1Cr processed by SLM.
Design/methodology/approach
An experimental approach is adopted to investigate porosity and mechanical properties of SLM specimens and its comparison with standard material AMPCOLOY 944. Optimization of porosity was performed using line and cube specimens; mechanical properties and microstructure were evaluated by tensile testing and metallography.
Findings
Optimum processing parameters for fabrication of Cu-alloy specimens with a relative density of 99.95 per cent were identified, and no cracks were detected. Mechanical testing of SLM specimens showed the ultimate tensile strength, proof stress of 0.2 and elongation of 380, 545 MPa and 16.9 per cent. The alloy is suitable for laser AM, thanks to its processability at a relatively high laser scanning speeds and thus its promising price of part/costs ratio.
Research limitations/implications
The paper describes the initial state of research – the follow-up tests focussed on mechanical testing, fatigue and statistical evaluation need to be conducted. The process parameters are developed only for bulk geometry – optimal setup for lattice structures and thin walls has not been explored yet.
Practical implications
The research findings in this work could be used for production of 3D printed parts and after the tuning of additional parameters, e.g. for up- and down-skin zones, could be used for special application such as energy exchange.
Originality/value
This work produces the processing of new material suitable for laser AM. Cu7.2Ni1.8Si1Cr alloy could be the prospective material from the group of Cu alloys suitable for moulds manufacturing and thermal applications.
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Jaime Schwartz and Carol Byrd‐Bredbenner
The purpose of this study was to explore the usefulness of a simplified version of cognitive response analysis (CRA) as a formative evaluation tool for health education materials…
Abstract
Purpose
The purpose of this study was to explore the usefulness of a simplified version of cognitive response analysis (CRA) as a formative evaluation tool for health education materials developed for small, unfunded projects.
Design/methodology/approach
A group of women (n=15), aged between 25 and 50 years, provided cognitive responses (CRs) that communicated their ongoing thoughts after viewing each slide in a narrated, online slide presentation that focused on nutrient content claims. Participants were assigned in a systematic random fashion to one of three CRA variations. In all three variations, participants simultaneously saw a slide and heard its narration and then provided their CRs while still viewing the slide. In Variation 1, a researcher wrote participants' CRs on a log sheet (n=5). Variation 2 participants' audiotaped their CRs which were later transcribed by a researcher (n=5). Variation 3 participants wrote their CRs on a log sheet. To assess the quality and usefulness of the CRs generated by each variation, the researchers categorized each CR into content‐related categories.
Findings
The time and effort required by the researcher and participants for all three variations of collecting CRs was similar. However, transcribing the audiotaped CRs presented a greater time burden to the researcher. Analysis of variance revealed that Variation 3 generated significantly fewer CRs than the other two variations. In addition, CRs from those in Variation 3 tended to be shorter and less specific and were less useful in refining the presentation because they provided limited guidance on needed improvements. In contrast, the CRs generated by Variations 1 and 2 were judged to be more useful in identifying improvements that could optimize the value of the presentation.
Originality/value
The results suggest that a simplified version of CRA is a valuable, efficient, and low‐cost tool for formative evaluation of health education materials.
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The purpose of this study is to examine the influence of semantic fluency on consumers' aesthetic evaluation in graphic designs with text and the mediating effect of visual…
Abstract
Purpose
The purpose of this study is to examine the influence of semantic fluency on consumers' aesthetic evaluation in graphic designs with text and the mediating effect of visual complexity in this relationship.
Design/methodology/approach
The hypotheses are examined in three experiments. Experiments 1 and 2 both verify that Chinese consumers rated the designs with low (vs high) semantic fluency words as more beautiful, and Experiment 3 further confirmed this effect in non-Chinese speakers.
Findings
Confirmed by Chinese and non-Chinese consumers, high fluency text leads to lower perceived visual complexity and less aesthetic perception of the entire design.
Research limitations/implications
Findings enrich the theory of beauty standards and put forward challenges to the positive relationship between processing fluency and aesthetic pleasure. Findings are limited to the decorative function of text, and lack discussions on how designers should balance when the informational function of text is equally important.
Originality/value
This study is the first to discuss how designs with text influence consumers' aesthetic perception and provides meaningful guidelines of transnational marketing for fashion designers and enterprises.
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Leighton Jones, Xujun Luo, Algy Kazlauciunas and Long Lin
This paper aims to synthesise and evaluate the properties of a novel smart material consisting of a metal-free organic black pigment with a unique chromophore for bifunctional…
Abstract
Purpose
This paper aims to synthesise and evaluate the properties of a novel smart material consisting of a metal-free organic black pigment with a unique chromophore for bifunctional applications in optoelectronics.
Design/methodology/approach
A robust and highly efficient organic reaction, namely, a double [2 + 2] cycloaddition, was deployed to transform a rod-like structure for charge-transfer applications to a strongly conjugated light-absorbing molecule for both optical and electronic applications.
Findings
The synthesis and characterisation of an air-stable metal-free black pigment is reported, which contains an unconventional donor–acceptor panchromatic chromophore with an absorption window spanning 600 nm; the compound was synthetically converted from an organic semiconducting molecular rod and retains strong charge-transfer properties. The chromophore comprises tetracyanoquinodimethane adduct on either side of a dithienothiophenyl core, capped with hexyl thiophenes that ensure solubility in common organic solvents. Its propensity to form excellent thin films on different substrates such as glass and paper, with a total opacity in organic solvent, gives it the potential for wide-ranging applications in organic optoelectronics.
Research limitations/implications
The synthetic chemistry and fundamental properties are investigated in the present study, with more detailed treatments and analysis to be soon developed. One leading smart material is presented, with further derivatives under investigation.
Practical implications
The work presented shows the possibility of converting structures from one application to another with relative ease, but how they retain properties for both, using well-known and facile conditions.
Originality/value
The structures are novel and an enhanced air-stable organic panchromatic chromophore is reported for processing in common organic solvents.
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