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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.

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.

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.

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.

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.

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.

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.

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.

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.

Informal dwellings describe makeshift lodgings made from temporary materials, such as plastic, corrugated iron, sheeting, packing cases, or wood. These units allow low-income groups to informally occupy land and create their habitable space in a phased manner. This article focuses on elements of the urban morphology, such as density, accessibility, and operating assortment of informally built areas in the southern region of Montenegro.

The author examines the urban morphologies of four urban areas, whose informality is traditionally viewed as markers of decline and despair. Using observations, questionnaires, and semi-structured interviews, the investigator maps dwellings in Ulcinj, Budva, Tivat, and Herceg Novi neighbourhoods. The researcher interrogated participants about land distribution during the construction of sheds, buildings' outline and orientation toward the street, and activities performed in their dwellings, such as living, working, and accommodating relatives and guests. This methodology tests the hypothesis, formulated as a deeper understanding of urban morphology for examining the interweaving of informally built settlements with the rest of the city.

A cartographic investigation is used to reframe customary rights of low-income populations to land inclusion and their place in the city. The results clearly show that the location and lifestyle are designed to obfuscate the vulnerable populations from the public view, disconnected from policymaking, and ignored by urban planning projects. However, the interviewees' destinations orientation away from the downtowns represents the possibility of reconfiguring existing urban planning practices. For creating alternative urbanisation, the orientation of less visible neighbourhoods presents a model for building regulations embedded in social forces and cultural habits of all social and ethnic groups.

This study did not address the implementation of social hosing policies and the logistical limitations of realising them by the local and national governments. During firework, the author encountered dwellers outside four studied low-income neighbourhoods in the south region of Montenegro. Mapping morphological elements of these generally small clusters of informal built units are left for future research. Future studies could examine how informality is performed in Montenegro by moderate and high-income groups as an assemblage of different power relationships and urban practices.

The argument is based on counter urbanism as the orientation and destination of less visible neighbourhoods for creating building regulations embedded in social forces and cultural habits of all social and ethnic groups. This study showed that the urban morphology of informality in the coastal cities of Montenegro lays the ground for alternative urban planning practices based on the different interconnection of districts. The outcome is a strong link between different social and ethical groups through self-building practices.

In coastal cities of Montenegro, Roma, Ashkali, and Egyptian live with other low-income groups in unsanitary settlements characterised by poor living conditions, low-quality illegally built housing, no plumbing or sewage systems, and overcrowded urban areas. Mapping morphological elements of less visible urban areas propose shifting from top-down urban planning policies to a participatory model of developing urban areas.

The assemblage of informally built urban areas legitimise place in the city that goes against the housing market's dominant logic and exceeds alternative logics of building production. This article outlined the urban morphologies of four urban areas for turning the image of informality away from decline and despair to lessons of urban interconnection. By creating different maps, the author presented a diverse orientation of four case studies based on density, accessibility, and operating assortment.

This paper aims to develop a method to improve the accuracy of tolerance analysis considering the spatial distribution characteristics of part surface morphology (SDCPSM) and local surface deformations (LSD) of planar mating surfaces during the assembly process.

First, this paper proposes a skin modeling method considering SDCPSM based on Non-Gaussian random field. Second, based on the skin model shapes, an improved boundary element method is adopted to solve LSD of nonideal planar mating surfaces, and the progressive contact method is adopted to obtain relative positioning deviation of mating surfaces. Finally, the case study is given to verify the proposed approach.

Through the case study, the results show that different SDCPSM have different influences on tolerance analysis, and LSD have nonnegligible and different influence on tolerance analysis considering different SDCPSM. In addition, the LSD have a greater influence on translational deviation along the z-axis than rotational deviation around the x- and y-axes.

The surface morphology with different spatial distribution characteristics leads to different contact behavior of planar mating surfaces, especially when considering the LSD of mating surfaces during the assembly process, which will have further influence on tolerance analysis. To address the above problem, this paper proposes a tolerance analysis method with skin modeling considering SDCPSM and LSD of mating surfaces, which can help to improve the accuracy of tolerance analysis.

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

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.

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.

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.

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

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.

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

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.

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.

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.

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.

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.

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.

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

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

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.

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.

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.