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This research establishes a suitable casting model for magnesium alloy wheel. The casting of the wheel is an element that must be considered in the design of the wheel. Casting is an important basic process and technology in the field of machinery which is widely used in production, transportation, national defense, social life and other aspects. Computer numerical simulation of the casting process can shorten the product manufacturing cycle, reduce product costs, reduce casting defects and ensure product quality. The casting material in this study is AZ91 magnesium alloy used for wheel lightweight.

Lightweight research of automobile is a significant trend, and people are paying attention to the lightweight design of automobiles. Higher requirement was proposed on design and casting performance of the wheel which is an important part of lightweighting vehicle. In order to achieve better quality, the parametric studies of alloy wheel and casting are necessary. This research designs a new model of automobile wheel, to ensure energy efficiency, the wheels must be as lightweight as possible, using magnesium alloy material for lightweight.

Analysis of casting process is a very complex issue. This research based on finite element theory and actual production, designed reasonable casting model, instant filling and solidification data were obtained. Aiming at reducing casting defects, process improvement of casting riser structure was designed. On the basis of the foundation, it has important guiding significance for actual foundry production.

This research establish a suitable casting model for magnesium alloy wheel. Aiming at reducing casting defects, process improvement of casting riser structure were designed.

The purpose of this research is to ascertain the feasibility of fabricating polymer optical fibers (POFs) based textile structures by knitting with Polymethylmethacrylate (PMMA) based optical fibers for textile sensor application. It has long been established that by using the principles of physics, POFs have the capability to function as sensors, detecting strain, temperature and other variables. However, POF applications such as strain and pressure sensing using knitting techniques has since not been very successful due to a number of reasons. Commercially available PMMA-based optical fibers tend to be fragile and susceptible to breakages when subjected to stress during the knitting processes. Also light transmitted within these fibers is prone to leakage due to the curvature that results when optical fibers are interlaced or interlooped within fabric structures.

Using Stoll’s multi-gauge CMS 350 HP knitting machine, five fabric structures namely, 1 × 4 float knit structure, tunnel inlay knit structure, 3:1 fleece fabric and 2:1 fleece fabric structure respectively were used to knit sensor samples. The samples were subsequently tested for length of illumination and sensitivity relative to applied pressure.

The results of this preliminary study establish that embedding plastic optical fibers into a knitted structure during the fabric formation process for soft strain sensor application possible. The best illumination performance was recorded for tunnel inlay structure which had an average of 94 cm course length of POF being illuminated. Sensor sensitivity experiments also establish that the relative spectral intensity of the fiber is sensitive to both light and pressure. Problems encountered and recommendations for further research have also been discussed and proffered.

Due to resource limitations, an innovative technique (use of precision weight set) was used to apply pressure to the sensors. Consequently, information regarding the extent of corresponding sensor deformation has not been used in this initial analysis.

Because the fundamental step toward finding a solution to any engineering problem is the acquisition of reliable data, and considering the fact that most of the popular technologies used for soft textile sensors are still bedeviled with the problem of signal instability and noise, the success of this application thus has the tendency to promote the wide spread adoption of POF sensors for smart apparel applications.

As far as research on soft strain sensors is concerned, to the best of the authors’ knowledge, this is the first study to have attempted to knit deformable sensors using commercially available POFs.

With the rapid increase in both household discretionary income and housing price, how to improve housing affordability is the vital challenge for China, especially for the northwestern region where the household income is lower than that in the eastern region. This paper aims to provide an insight into the housing affordability by analyzing the influence factors of purchasing standard housing in Lanzhou, which is the second largest city in Northwest China.

Price to income ratio (PIR) and housing affordability index (HAI) approaches were applied in this study to measure housing affordability for Lanzhou.

The results show that the PIR values for Lanzhou range from 6.02 to 7.23 between 2001 and 2008. The value exhibits an increasing trend before 2004 and a decreasing trend after 2004. The HAI values vary between 62.0 and 83.2 and are higher from 2001 to 2003 than those from 2004 to 2008. It was observed that the level of influence of the household discretionary income, housing price and the mortgage interest rate on these two values differs significantly in the different studied periods. This indicates that housing affordability in Lanzhou is lower than the acceptable level.

The paper establishes an understanding of the level of housing affordability in Northwest China, and provides the basis for the formulation of the new government's housing policy for this region.

The purpose of this paper is to study the tribology behavior of steel–steel contact under the lubrication of water-based drilling mud with different oleic acid-filled microcapsules as lubricant additives.

A ball-on-disc tribometer was used to evaluate the lubrication properties of the steel–steel contact. The wear tracks of the worn surfaces were observed by a scanning electron microscope.

Results show that the dependence of both friction and wear on the category of additives shares a consistent pattern. In contrast to oleic acid and empty microcapsules, oleic acid-filled microcapsules achieve the best tribological performance which is related to the lubricant effect of oleic acid and the isolation and rolling abilities of microcapsules.

This study provides a helpful method of encapsulated lubricant additives to prolong lubrication performance for steel–steel contact.

This study has applied microcapsules to improve the tribological properties of drilling mud.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0320/

Supplier selection for defence procurement is a crucial function of a Ministry of Defence. The Ministry spends huge amounts of money each year to procure a vast array of equipment, goods and services. The ongoing financial crisis demands less subjective and more cost-saving methods for selecting a supplier. The approach advocated in this article integrates Analytic Hierarchy Process (AHP) with Goal Programming (GP) in order to combine conflicting criteria to select the best suppliers and allocate optimum order quantities among them. This paper presents a model close to real-world situations. Findings demonstrate that cost savings is a feasible result along with a viable combination of conflicting criteria in the suppliers' selection area.

Against the backdrop of the contribution of design to the occurrence of occupational injuries and illnesses in construction, design for occupational safety and health (DfOSH) is increasingly becoming prominent in the construction sector. To ensure that design interventions are safe for construction workers to build and maintain, design firms need to have the appropriate organisational capability in respect of DfOSH. However, empirical insight regarding the attributes that constitute DfOSH organisational capability is lacking. The purpose of this paper, which trailblases the subject of DfOSH organisational capability in construction, is to address two key questions: what organisational attributes determine DfOSH capability? What is the relative priority of the capability attributes?

The study employed three iterations of expert focus group discussion and a subsequent three-round Delphi technique accompanied by the application of voting analytic hierarchy process.

The study revealed 18 capability attributes nested within six categories, namely: competence (the competence of organisation’s design staff); strategy (the consideration of DfOSH in organisation’s vision as well as the top management commitment); corporate experience (organisation’s experience in implementing DfOSH on projects); systems (systems, processes and procedures required for implementing DfOSH); infrastructure (physical, and information and communication technology resources); and collaboration (inter- and intra-organisational collaboration to implement DfOSH on projects). Whilst these categories and their nested attributes carry varying weights of importance, collectively, the competence-related attributes are the most important, followed by strategy.

The findings should enable design firms and other key industry stakeholders (such as the clients who appoint them) to understand designers’ DfOSH capability better. Additionally, design firms should be able to prioritise efforts/investment to enhance their DfOSH capability.

For construction organisations to be effective at implementing an integrated safety, health and environmental (SHE) management system, they require the right level of organisational capability. This capability includes the policies, systems and resources of the organisation. However, within the academic literature, it is unclear which organisational attributes of construction companies are important for implementing integrated SHE management. This study aims to explore the organisational attributes that determine integrated SHE management capability and their relative priorities.

The study used a literature review supported by expert verification and a subsequent three-round expert Delphi technique accompanied by applying the voting analytical hierarchy process.

The study identified 20 attributes grouped under five main thematic categories. These are strategy (the organisation’s vision and top management commitment); process (the organisation’s procedures and processes for SHE management); people (organisation’s human resources, their competence, roles, responsibilities and involvement in SHE management); resources (organisation’s physical and financial resources for SHE management) and information (SHE related documents, data, records and their communication across an organisation). While these thematic categories and the attributes within carry different weights of importance, the strategy-related attributes are the most important, followed by the people-related attributes.

The results of this study should enable construction companies and key industry stakeholders to understand construction companies’ capability to successfully implement an integrated SHE management system. Furthermore, construction companies should be able to prioritise efforts or investments to enhance their SHE management capability.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

The purpose of this paper is to develop a framework for route selection in multimodal transportation which can reduce cost, lead time, risk and CO₂ emission in multimodal transportation systems.

This research proposes the development of a framework for route selection in multimodal transportation that includes a six-phase framework to select an optimal multimodal transportation route. The first phase is to collect the data of each route and select the origin and destination. The second phase is to calculate time and cost of each route by using a multimodal transport cost-model. In the third phase, the CO₂ emissions are calculated based upon the 2006 guidelines of Intergovernmental Panel on Climate Change. The fourth phase proposes an integrated quantitative risk assessment, analytic hierarchy process (AHP) and data envelopment analysis methodology to evaluate the multimodal transportation risk. The fifth phase is to prioritize criteria by using the AHP which can be used in the objective function. The final phase is to calculate the optimal route by using the zero-one goal programming.

The aims of the model are to minimize transportation costs, transportation time, risk and CO₂ emission.

The approach has been tested on a realistic multimodal transportation service, originating from Bangkok in Thailand to a destination at Da Nang port in Vietnam. The results have shown that the approach can provide guidance in choosing the lowest cost route in accordance with other criteria, and to minimize the CO₂ emission effectively.

The contribution of this research lies in the development of a new decision support approach that is flexible and applicable to logistics service providers, in selecting multimodal transportation route under the multi-criteria in term of cost, time, risk and importantly the environmental impact.