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1 – 10 of 148Y. Ichikawa, K. Kawamura, N. Fujii and Theramast Nattavut
Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely…
Abstract
Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely microinhomogeneous material are as follows: the microstructure is characterized in detail, the local distribution of material properties is identified by experiment or simulation, and the microscale characteristics are related to the macroscale behavior by a seamless manner. For characterizing a microstructure of bentonite, we introduce a conforcal laser scanning microscope (CLSM) together with SEM. By CLSM we can specify a 3D configuration under atmospheric condition. Properties of water‐saturated bentonite are mainly controlled by hydrated montmorillonite, which is the major clay mineral of bentonite. Smectite minerals including montmorillonite are extremely fine and poorly crystallized, so it is difficult to determine the properties by experiment. We inquire into the physicochemical properties by a molecular dynamics simulation method. Then, we develop a multiscale homogenization method to extend the microscopic characteristics to the macroscopic behavior. We show numerical examples of a diffusion problem.
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Sen Peng, Huiping Cui and Min Ji
The new campus of Tianjin University was designed, built and now operates following a green and sustainable concept. The campus’ eco-friendly water environment was formed by…
Abstract
The new campus of Tianjin University was designed, built and now operates following a green and sustainable concept. The campus’ eco-friendly water environment was formed by establishing a water recycling system. The campus is divided into three drainage sections based on the masterplan. Each drainage section adopts different methods of collecting, utilizing and discharging water according to specific conditions, aimed at achieving both high drainage capability and the efficient utilisation of rainwater. The campus was designed so runoff pollution is reduced through the utilisation of low-impact development methods, ensuring the quality of the recharge water. Through studying the fundamentals of treatment measures and models for simulating water quality, water circulation, constructed wetlands and pollution control of rain runoff, parameters for efficient water recycling could be mathematically forecast, ensuring that stakeholders can be continuously engaged in improving and preserving the water quality of landscaped water on campus. The overall system integrates a variety of measures being implemented into one cohesive entity, which contributes to establishing the sustainable and healthy water cycling system of the green campus.
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Wang Zhizhong, Han Chao, Guosheng Huang, Han Bin and Han Bin
The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient…
Abstract
Purpose
The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.
Design/methodology/approach
This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.
Findings
There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.
Originality/value
It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.
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Mohammad A. Hassanain, Ali K. Alnuaimi and Muizz O. Sanni-Anibire
This paper aims to present an assessment of user satisfaction of an innovative workplace design, otherwise known as flexible workplaces.
Abstract
Purpose
This paper aims to present an assessment of user satisfaction of an innovative workplace design, otherwise known as flexible workplaces.
Design/methodology/approach
The study first sought to establish the level of flexibility of the workplace through the identification of flexibility criteria presented in a checklist format. In total, 29 criteria were identified and subsequently assigned weights by ten professionals. These professionals further assessed a case study office building through a walkthrough exercise to determine its level of flexibility. Furthermore, a post occupancy evaluation (POE) was conducted to assess the level of users’ satisfaction with functional performance elements. Questionnaire surveys were administered to 142 users, with a 63 per cent response rate. The feedback was analyzed and presented using the mean satisfaction index approach.
Findings
The results showed that the total flexibility achieved by the facility is 67.63 per cent, which is considered to be “averagely flexible”. The POE results also showed that users were strongly dissatisfied (SD) with the “adequate number of enclosed offices,” which is one of the corner-stones of flexibility where open-plan offices are strongly encouraged. Users expressed dissatisfaction with other issues, while their overall satisfaction with the facility was noted.
Originality/value
This study is based on the premise that innovative workplace facilities will only fulfill its intended objectives if designers consider the satisfaction of its users. The study makes a specific contribution in the assessment of workplace flexibility and occupants’ satisfaction of flexible workplaces. This will be of significant value to facility managers, designers and space planners involved in the design and management of workplace facilities.
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Joel West and David Wood
Two key factors in the success of general-purpose computing platforms are the creation of a technical standards architecture and managing an ecosystem of third-party suppliers of…
Abstract
Two key factors in the success of general-purpose computing platforms are the creation of a technical standards architecture and managing an ecosystem of third-party suppliers of complementary products. Here, we examine Symbian Ltd., a startup firm that developed a strong technical architecture and broad range of third-party complements with its Symbian OS for smartphones. Symbian was shipped in nearly 450 million mobile phones from 2000 to 2010, making it the most popular smartphone platform during that period. However, its technical and market control of the platform were limited by its customers, particularly Nokia. From 2007 onward, Symbian lost market share and developer loyalty to the new iPhone and Android platforms, leading to the extinction of the company and eventually its platform. Together, this suggests lessons for the evolution of a complex ecosystem, and the impact of asymmetric dependencies and divided leadership upon ecosystem success.
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Keiko Ishii, Yukie Takemura, Naoko Ichikawa, Keiko Kunie and Ryohei Kida
This study aims to investigate the relationship between a nursing group’s organizational socialization (OS) and the organizational learning (OL) subprocesses of information…
Abstract
Purpose
This study aims to investigate the relationship between a nursing group’s organizational socialization (OS) and the organizational learning (OL) subprocesses of information acquisition, information distribution, information interpretation, information integration and organizational memory.
Design/methodology/approach
A cross-sectional study, with an anonymous self-report questionnaire, was conducted at two university hospitals in Japan. OL was measured using the scale for OL subprocesses, while OS was measured using the scale for learning about the external environment. The questionnaire was administered from August to October 2018. Among the 1,077 nurses recruited from 34 wards, data from 466 nurses from 24 wards were analyzed. To verify the influence of the group’s OS on each OL subprocess, two-level hierarchical linear modeling with fixed effects was performed. Individual nurses’ OS was analyzed using centering within clusters and the group’s OS was analyzed using each ward’s average OS score by performing grand mean centering.
Findings
Nursing groups’ OS was positively and significantly associated with information interpretation and information integration, but not with information acquisition, information distribution and organizational memory.
Originality/value
This study expands OS and OL research by focusing on the relationship between the degree of OS of an entire group and the OL subprocess. When the degree of homophily of value, rule, knowledge and behavior of the entire group increases, the information understanding and the formation of new explicit knowledge may also increase in the group.
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The aim of this paper is to identify the factors that influence the provision of sustainable and flexible office workplace in built‐facilities, and further, classify these factors…
Abstract
Purpose
The aim of this paper is to identify the factors that influence the provision of sustainable and flexible office workplace in built‐facilities, and further, classify these factors under several categories, where commonalities are shared.
Design/methodology/approach
The author has analyzed the published literature for the purpose of reviewing the origin of office workplace design and the reasons that promoted the development of flexible workplace in office‐based environments. A sum of 18 factors for facilitating the provision of the flexible workplace were identified. These factors were classified under four categories, including planning of the building, layout of the physical workplace, information technology networking, and building service systems.
Findings
The survey of literature has revealed that there is no comprehensive overview of factors that designers, developers, investors, facility managers, and planners can use to provide sustainable and flexible workplace facilities, where flexibility relates to the concept of the physical layout and functional opportunities of the workspace. Based on a study of the literature, 18 factors for facilitating the provision of the flexible workplace have been identified.
Originality/value
Designing a sustainable office work environment is as challenging a task today as ever. New ways of working have arisen and new technologies are being introduced into office work activities. This paper presents advice to designers, planners and real estate developers to consider the concept of designing flexible workplaces to meet the emergence of new technologies and the increase in business competition.
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Wei Zhang, Zhongmin Deng and Jingsheng Li
The purpose of this paper is to propose strategies for satellite cluster non‐coplanar orbit transfer to reduce fuel cost of formation maintenance and orbit maneuver.
Abstract
Purpose
The purpose of this paper is to propose strategies for satellite cluster non‐coplanar orbit transfer to reduce fuel cost of formation maintenance and orbit maneuver.
Design/methodology/approach
This research tries to use geometric method model to describe the relative motion of satellites in the cluster non‐coplanar orbit transfer, and genetic algorithm (GA) to optimize the proposed maneuver strategies.
Findings
Compared with the C‐W equations, the geometric method model is found to be more precise. Three strategies are proposed and optimized to maintain the relative orbit and a strategy of indefinite phase and non‐synchronous costs least fuel.
Practical implications
Geometric method model can be used to describe the relative motion of satellite cluster, especially on elliptical orbits considering the effects of perturbation, with a simple form and good accuracy. Fuel cost minimization is one of the most important issues in formation flight mission.
Originality/value
This paper provides dynamics analysis about formation non‐coplanar orbit transfer, which is involved in minor researches.
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Xue Xinhua, Zhang Wohua and Xingguo Yang
The paper aims to clarify the relationship between the micro-structures of porous media and the coefficient of permeability. Most materials involve different types of defects like…
Abstract
Purpose
The paper aims to clarify the relationship between the micro-structures of porous media and the coefficient of permeability. Most materials involve different types of defects like caves, pores and cracks, which are important characters of porous media and have a great influence on the physical properties of materials. To study the seepage mechanical characteristics of damaged porous media, the constitutive model of porous media dealing with coupled modeling of pores damage and its impact on permeability property of a deforming media was studied in this paper.
Design/methodology/approach
The paper opted for an exploratory study using the approach of continuum damage mechanics (CDM).
Findings
The paper provides some new insights on the fluid dynamics of porous media. The dynamic evolution model of permeability coefficient established in this paper can be used to model the fluid flow problems in damaged porous media. Moreover, the modified Darcy's law developed in this paper is considered to be an extension of the Darcy's law for fluid flow and seepage in a porous medium.
Research limitations/implications
Owing to the limitations of time, conditions, funds, etc., the research results should be subject to multifaceted experiments before their innovative significance can be fully verified.
Practical implications
The paper includes implications for the development of fluid dynamics of porous media.
Originality/value
This paper fulfils an identified need to study the relationship between the micro-structures of porous media and the coefficient of permeability.
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