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Article
Publication date: 17 November 2021

G.K.T. Weerasekara, Archchana Shandraseharan, B.A.K.S. Perera and Vijitha Disaratna

The morphology of a building describes its outline and influences its architectural aesthetics and the cost directly. However, the literature on the impact of morphology

Abstract

Purpose

The morphology of a building describes its outline and influences its architectural aesthetics and the cost directly. However, the literature on the impact of morphology on the aesthetics and cost of urban detached residential buildings is scarce. Thus, this study is significant because its aim was to identify the critical building morphology factors and the relationship that each of them maintains with the cost and aesthetics of urban detached residential buildings.

Design/methodology/approach

The multi-method qualitative approach was used to collect the required empirical data through interviews and case studies and to identify the effect of the morphology factors on the aesthetics and construction cost of urban residences in Sri Lanka, respectively. The collected data were analyzed using manual content analysis and descriptive statistics.

Findings

The study findings revealed that the morphology factors such as the roof and circulation spaces, open spaces and voids have a high impact on both the building cost and aesthetics. These findings will assist building designers in making effective design decisions on building costs and aesthetics so that a successful design outcome satisfying both the clients and design team could be obtained.

Originality/value

Although morphology has an impact on the cost and aesthetic of buildings, literature on the subject is scarce. Thus, this study is significant in that it aimed at identifying the significant building morphology factors in urban detached residential buildings and identifying their relationship with the cost and aesthetic of those buildings.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 August 2002

J.G. Lee, F. Guo, K.N. Subramanian and J.P. Lucas

The influence of the thermal reflow profile on the formation and resultant morphology of the intermetallic layer that developed at the Ni particle reinforcements within an…

Abstract

The influence of the thermal reflow profile on the formation and resultant morphology of the intermetallic layer that developed at the Ni particle reinforcements within an eutectic Sn‐Ag composite solder matrix was investigated. The composite solder was fabricated by mechanically dispersing 15 vol% Ni particles into eutectic Sn‐3.5Ag solder paste. Two distinct intermetallic compound (IMC) morphological microstructures were observed around the Ni reinforcements. IMC morphological microstructure apparently varied depending on the amount of heat input and differences in heating rates used in the reflow profile. A “sunflower” IMC morphology was typically noted when the total amount of heat input was small. However, with sufficient heat input, a faceted “blocky” IMC morphology was consistently achieved. Multiple‐reflow thermal profiling experiments were conducted to measure and compare the amount of heat input necessary to change the sunflower IMC morphology around Ni particle reinforcements to the blocky morphology.

Details

Soldering & Surface Mount Technology, vol. 14 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 10 April 2019

Qingchao Sun, Xiaokai Mu, Bo Yuan, Jiawen Xu and Wei Sun

This paper aims to distinguish the relationship between the morphology characteristics of different scales and the contact performance of the mating surfaces. Also, an…

Abstract

Purpose

This paper aims to distinguish the relationship between the morphology characteristics of different scales and the contact performance of the mating surfaces. Also, an integrated method of the spectrum analysis and the wavelet transform is used to separate the morphology characteristics of the actual machined parts.

Design/methodology/approach

First, a three-dimensional (3D) surface profilometer is used to obtain the surface morphology data of the actual machined parts. Second, the morphology characteristics of different scales are realized by the wavelet analysis and the power spectral density. Third, the reverse modeling engineering is used to construct the 3D contact models for the macroscopic characteristics. Finally, the finite element method is used to analyze the contact stiffness and the contact area of the 3D contact model.

Findings

The contact area and the nominal contact pressure Pn have a nonlinear relationship in the whole compression process for the 3D contact model. The percentage of the total contact area of the macro-scale mating surface is about 70 per cent when the contact pressure Pn is in the range of 0-100 MPa, and the elastic contact area accounts for the vast majority. Meanwhile, when the contact pressure Pn is less than 10MPa, the influence factor (the relative error of contact stiffness) is larger than 50 per cent, so the surface macro-scale morphology has a weakening effect on the normal contact stiffness of the mating surfaces.

Originality/value

This paper provides an effective method for the multi-scale separation of the surface morphology and then lays a certain theoretical foundation for improving the surface quality of parts and the morphology design.

Details

Engineering Computations, vol. 36 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 16 January 2018

Peng Yao, Xiaoyan Li, Fengyang Jin and Yang Li

This paper aims to analyze the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints in electronic packaging.

Abstract

Purpose

This paper aims to analyze the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints in electronic packaging.

Design/methodology/approach

Because of the infeasibility of analyzing the morphology transformation intuitively, a novel equivalent method is used. The morphology transformation on the Cu3Sn grains, during the formation of full Cu3Sn solder joints, is regarded as equivalent to the morphology transformation on the Cu3Sn grains derived from the Cu/Sn structures with different Sn thickness.

Findings

During soldering, the Cu3Sn grains first grew in the fine equiaxial shape in a ripening process until the critical size. Under the critical size, the Cu3Sn grains were changed from the equiaxial shape to the columnar shape. Moreover, the columnar Cu3Sn grains could be divided into different clusters with different growth directions. With the proceeding of soldering, the columnar Cu3Sn grains continued to grow in a feather of the width growing at a greater extent than the length. With the growth of the columnar Cu3Sn grains, adjacent Cu3Sn grains, within each cluster, merged with each other. Next, the merged columnar Cu3Sn grains, within each cluster, continued to merge with each other. Finally, the columnar Cu3Sn grains, within each cluster, merged into one coarse columnar Cu3Sn grain with the formation of full Cu3Sn solder joints. The detailed mechanism, for the very interesting morphology transformation, has been proposed.

Originality/value

Few researchers focused on the morphology transformation of interfacial phases during the formation of full intermetallic compounds joints. To bridge the research gap, the morphology transformation on the Cu3Sn grains during the formation of full Cu3Sn solder joints has been studied for the first time.

Details

Soldering & Surface Mount Technology, vol. 30 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 17 July 2009

J. Ajith Kumar and L.S. Ganesh

The purpose of this paper is to present and describe a morphology of the research literature on knowledge transfer in organizations.

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Abstract

Purpose

The purpose of this paper is to present and describe a morphology of the research literature on knowledge transfer in organizations.

Design/methodology/approach

This morphology, which is a comprehensive framework characterizing the knowledge transfer literature in terms of dimensions and options, was developed by an extensive scanning of the pertinent literature.

Findings

Eight dimensions were found suitable to characterize the knowledge transfer research literature. Corresponding to each dimension, two to six options were found.

Research limitations/implications

The morphology demonstrates the extensiveness and variety of knowledge transfer research. To academics, the morphology can serve as a map of the knowledge transfer territory. Using the morphology, researchers can easily assess how an existing study fits in with the entire body of knowledge transfer research. Secondly, they can discern areas that have received less attention in comparison to others and thus identify gaps they may wish to address in a new study. KM practitioners can use the morphology to assess their knowledge transfer strategies in terms of the dimensions it currently has/lacks, and take appropriate decisions.

Originality/value

To the best of the authors' knowledge, a morphological approach has not been attempted so far to characterize KM research literature. The approach used can be applied to other areas of management as well, for similar purposes.

Details

Journal of Knowledge Management, vol. 13 no. 4
Type: Research Article
ISSN: 1367-3270

Keywords

Article
Publication date: 1 December 2017

Sahar Hassan Imam

Relating development control regulations to urban morphology analysis concepts is essential to deal with incremental change in existing contexts, relating urban morphology

Abstract

Relating development control regulations to urban morphology analysis concepts is essential to deal with incremental change in existing contexts, relating urban morphology analysis to intangible factors of change such as land economics, human needs, politics and ideologies, helps protecting character and value of contexts from unguided change controlled by waves of political decisions, change of densities and land values. The first part of the paper discusses different approaches to urban morphology analysis, the need to development control regulations to protect character and value, the incremental nature of urban change, and urban morphology's non physical aspects effect on urban change. The second part of the paper reviews two case studies in France and Egypt to assess development control regulations in each case, how it affected urban change and area character, and examines whether urban morphology analysis was part of Development control regulations or not. It concludes with the evaluation of the second case, and the development of a frame work linking non physical factors affecting incremental change with morphological studies, showing the need to relate development control regulations to morphological analysis of town's form and non physical variables affecting form change to guide positively incremental change.

Details

Open House International, vol. 42 no. 4
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 2 February 2015

Wei Liu, Rong An, Chunqing Wang and Yanhong Tian

The purpose of this paper is to investigate the effect of typical morphologies of Au-Sn IMCs (intermetallic compounds) at the interfaces of solder and pads on shear…

Abstract

Purpose

The purpose of this paper is to investigate the effect of typical morphologies of Au-Sn IMCs (intermetallic compounds) at the interfaces of solder and pads on shear properties of laser reflowed micro-solder joints.

Design/methodology/approach

Sn-2.0Ag-0.75Cu-3.0Bi (SnAgCuBi) solder balls (120 μm in diameter), pads with 0.1, 0.5, 0.9 or 4.0 μm thickness of Au surface finish, and different laser input energies were utilized to fabricate micro-solder joints with Au-Sn IMCs having different typical morphologies. The joints were performed by a shear test through a DAGE bond test system. Fracture surfaces of the joints were analyzed by scanning electron microscopy and energy-dispersive X-ray spectrometry to identify fracture modes and locations.

Findings

Morphologies of Au-Sn IMCs would affect shear properties of the joints remarkably. When needle-like AuSn4 IMCs formed at the interfaces of solder and pads, almost entire surfaces presented the manner of ductile fracture. Moreover, shear forces of this kind of solder joints were higher than those of joints without Au-Sn IMCs or with a nearly continuous/continuous Au-Sn IMCs layer. The reason was that the shear performance of the solder joints with needle-like AuSn4 IMCs was enhanced by an interlocking effect between solder and needle-like AuSn4 IMCs. As a nearly continuous or continuous Au-Sn IMCs layer formed, the fracture surfaces presented more character of brittle than ductile fracture. However, if an Au layer still remained under Au-Sn IMCs, the shear performance of the joints would be enhanced.

Originality/value

The results in this study can be used to optimize microstructures and shear properties of laser reflowed micro-solder joints.

Details

Soldering & Surface Mount Technology, vol. 27 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 13 March 2017

Xiulin Xu, Xing Lu, Zuoxiang Qin and Dalong Yang

This paper aims to study the friction layer and tribological property of polyimide (PI)–matrix composites under different friction speeds.

Abstract

Purpose

This paper aims to study the friction layer and tribological property of polyimide (PI)–matrix composites under different friction speeds.

Design/methodology/approach

Friction tests were conducted under friction speeds ranging from 20-120 km/h and pressure of 0.57 MPa by a pin-on-disk tribometer.

Findings

The results indicate that the friction coefficient decreases with the increasing of the friction speed. Under different friction speeds, the structure of the friction layer and debris are different, which affects the actual tribological performance of the composites. At low friction speed, the morphology of the friction layer is mainly particulate. The higher level of clenching action between the friction pair leads to a high friction coefficient, and the morphology of the particles in the particulate zone and the wear debris are mostly equiaxial particles. At high friction speed, the morphology of the friction layer is mainly a compact zone. The reduction of the surface roughness leads to a low friction coefficient. The debris collected on the counter surface at high friction speeds are mostly big sheets, and the morphology of the particles in the particulate zone is mostly rod-like. Controlling the conditions of the disk and the pin can reveal the influence of friction speed on the friction layer. The wear mechanisms at different friction speeds are also discussed.

Originality/value

By controlling the conditions of the disk and the pin to reveal the influence of friction speed on the friction layer, and the evolutions of the friction layer, wear debris were carefully inspected with the aim of demonstrating the relationship between friction speed and wear mechanism of PI–matrix composites.

Details

Industrial Lubrication and Tribology, vol. 69 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 5 April 2022

Yuquan Ni, Nannan Sun, Guixiang Zhu, Shujie Liu, Jun Liu and Guangneng Dong

This paper aims to study different morphology Cu6Sn5 effect on Babbitt alloy tribological properties.

Abstract

Purpose

This paper aims to study different morphology Cu6Sn5 effect on Babbitt alloy tribological properties.

Design/methodology/approach

Different morphology Cu6Sn5 of Babbitt was conducted by different cooling modes. Bare Babbitt was marked by Babbitt-0, Babbitt modified by first cooling mode (marked by Babbitt-1) and Babbitt modified by second cooling mode (marked by Babbitt-2). The microstructure and microhardness of specimens were tested. Then, tribological properties of Babbitt-0, Babbitt-1 and Babbitt-2 were performed by reciprocating mode under lubricated condition.

Findings

The results showed that shape Cu6Sn5 of Babbitt was changed from mixed needle and star-like shape to short rod-like or granular shape. The microhardness of Babbitt-1 was highest than that of Babbitt-0 and Babbitt-2. Compared with Babbitt-0 and Babbitt-2, tribological properties of Babbitt-1 were better under lubricated condition due to short rod-like and sparse distribution of Cu6Sn5. Moreover, the simulation result of strain and stress of Babbitt-1 was lowest than that of Babbitt-0 and Babbitt-2.

Originality/value

Different morphology (shape and distributed) of Cu6Sn5 was obtained by different cooling modes. Modulated different forms of Cu6Sn5 around SnSb was beneficial to improve Babbitt alloy tribological properties.

Details

Industrial Lubrication and Tribology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 2 December 2019

Yun Liu, Weiyuan Yu, Xuemin Sun and Fengfeng Wang

This paper aims to investigate the effect of ultrasonic vibration (USV) on the evolution of intermetallic compounds (IMCs), grain morphology and shear strength of soldered…

Abstract

Purpose

This paper aims to investigate the effect of ultrasonic vibration (USV) on the evolution of intermetallic compounds (IMCs), grain morphology and shear strength of soldered Ni/Sn/Ni samples.

Design/methodology/approach

The Ni/Sn/Ni joints were obtained through ultrasonic-assisted soldering. The formation of IMCs, their composition, grain morphology and the fractured-surface microstructures from shear tests were characterized using scanning electron microscopy and energy-dispersive x-ray spectroscopy.

Findings

Without USV, a planar interfacial Ni3Sn4 layer was formed at the Ni/Sn interface, and a few Ni3Sn4 grains were distributed in the soldered joint. The morphology of these grains was needle-shaped. With USV, several grooves were formed at the interfacial Ni3Sn4 layer due to ultrasonic cavitation. Some deepened grooves led to “neck” connections at the roots of the Ni3Sn4 grains, which accelerated the strong detachment of Ni3Sn4 from the substrate. In addition, two types of Ni3Sn4 grains, needle-shaped and granular-shaped, were observed at the interface. Furthermore, the shear strength increased with longer USV time, which was attributed to the thinning of the interfacial IMC layers and dispersion strengthening from the Ni3Sn4 particles distributed evenly in the joint.

Originality/value

The novelty of the paper is the detailed study of the effect of USV on the morphology, size changes of interfacial IMC and joint strength. This provides guidance for the application of ultrasonic-assisted soldering in electronics packaging.

Details

Soldering & Surface Mount Technology, vol. 32 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

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