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Metal laser-powder-bed-fusion using laser-beam parts are particularly susceptible to contamination due to particles attached to the surface. This may compromise so-called technical cleanliness (e.g. in NASA RPTSTD-8070, ASTM G93, ISO 14952 or ISO 16232), which is important for many 3D-printed components, such as implants or liquid rocket engines. The purpose of the presented comparative study is to show how cleanliness is improved by design and different surface treatment methods.

Convex and concave test parts were designed, built and surface-treated by combinations of media blasting, electroless nickel plating and electrochemical polishing. After cleaning and analysing the technical cleanliness according to ASTM and ISO standards, effects on particle contamination, appearance, mass and dimensional accuracy are presented.

Contamination reduction factors are introduced for different particle sizes and surface treatment methods. Surface treatments were more effective for concave design features, however, the initial and resulting absolute particle contamination was higher. Results further indicate that there are trade-offs between cleanliness and other objectives in design. Design guidelines are introduced to solve conflicts in design when requirements for cleanliness exist.

This paper recommends designing parts and corresponding process chains for manufacturing simultaneously. Incorporating post-processing characteristics into the design phase is both feasible and essential. In the experimental study, electroless nickel plating in combination with prior glass bead blasting resulted in the lowest total remaining particle contamination. This process applied for cleanliness is a novelty, as well as a comparison between the different surface treatment methods.

The research investigates the relationship between halal credence, awareness, certification, need for cognition (NC), effort, health consciousness, and satisfaction towards halal food (STHF). In addition, observe the influence of STHF on purchase intention explored. Finally, religiosity is examined as a moderator between STHF and halal purchase intention.

The data was collected from Muslim participants in Guangzhou and Shenzhen, China. A total of 476 respondents take part in this research. The data was collected from Muslims who eat food from halal food hotels. A purposive sampling technique is used to collect data from respondents. PLS-SEM is followed to test the proposed hypotheses.

The results reveal that halal credence, awareness, certification, effort, and health consciousness increase STHF. Conversely, NC does not influence STHF. Moreover, STHF significantly determines halal purchase intention. Finally, religiosity strengthens the positive association between STHF and purchase intention.

Food marketers and policy decision-makers can use research findings to enhance halal purchase intention. In China, Muslim customers usually search for halal food by putting in extra effort and seeing halal certification. They trust halal food because religiosity is their priority.

This initial research incorporates halal credence, halal awareness, certification, NC, effort, health consciousness, STHF, and religiosity to examine halal purchase intention using the theory of planned behavior (TPB).

Understanding the thermal performance of sandcrete hollow block walls in the tropic is very essential for occupants' well-being, productivity and efficiency, due to its widespread application in buildings in the study area. Lokoja, in Nigeria, lies in the warm humid zone with its attendant's high temperatures all year round. Thus, providing an acceptable walling material that will control the high indoor air temperature becomes imperative. This paper assessed sandcrete hollow blocks as a walling material used in Lokoja, to determine the thermal performances for effective thermal comfort of the residents.

It involves the construction of a habitable model building with the commonly available sandcrete hollow blocks in the area. One unit of Cryopak iMINI Temperature and Relative Humidity Data Logger called new generation intelligent iMINI with Serial Number and Product Code MX-CI-145–0009 and MX-HE-S-16-L was installed, to record the indoor air temperature and relative humidity data at an interval of one hour, for 12 months covering dry and wet seasons. The results of the recorded data were downloaded to an excel spread sheet for assessment and analysis throughout the seasons. The values were computed using the temperature–humidity index (THI) equation, with a view to determine the indoor thermal comfort level category.

The study revealed that sandcrete hollow block walls provide thermal discomfort of the indoor environment for both seasons, with attendant adverse effects in the comfort of the occupants. The paper concludes that proper orientation of buildings, planting of trees, use of low absorbing or reflective surface materials, application of cavity walls to receive insulation materials in between the hollow spaces provided, instead of the single walling as well as providing shading device elements, can improve users' comfort and also ameliorate the heat effect on the external surface of building transferred into the interior by conduction, radiation or convection within the area and in the tropics at large. Other thermally eco-friendly wall materials available in Lokoja includes timber, stabilized laterite–cement blocks, burnt bricks and earth-mud bricks which can be used to replace sandcrete hollow block walls. These alternative wall materials are used for construction of residential and office buildings by the colonial government of Sir Fredrick Lugard in the study area.

The application of sandcrete hollow blocks as a wall material is in vogue, not minding its thermal discomfort to the users and the environment; this is due to its availability and ease of production. The acceptability of this walling material requires holistic study to unravel the best way to reduce the thermal discomfort inherent in its application.

The author succeeded in revealing the thermal performance of sandcrete hollow blocks as walling material in Lokoja, the study area. It is a first attempt at understanding the performance for human comfort in the area. This will greatly assist the resident and other researchers to improve on the application of sandcrete hollow blocks as walling material towards ensuring that maximum indoor thermal comfort is achieved.

Transport is the main enabler of tourism, but also one of its main sources of environmental impact. This paradoxical condition is even more controversial if considering the reluctancy of policymakers to introduce traffic management strategies, as they fear possible drops in tourism demand. This chapter addresses the ‘tourism-traffic paradox’ as a wicked problem and explores adequate and efficient policy interventions to foster sustainable mobility in Alpine destinations, minimising rebound effects in tourism demand. The chapter is focussed on the exemplary case of the Dolomites World Heritage Site (WHS), as this Italian area has experienced a long-lasting process of evidence-informed decision-making in transport, with two pilot actions for traffic calming in 2017 and 2018. The main goal of those actions was to shift the modal choices of tourists, to optimise the traffic network use and to minimise environmental impacts. The policy interventions were rooted in a sustainability governance approach, that is, they were creating a government-led network of stakeholders, including several academic experts, involved in the transport planning and monitoring phase. Advantages and disadvantages of this government-led network to solve the tourism-traffic paradox are discussed in the chapter.

This paper explores the effects of land education on the practice of a White social studies teacher educator who wanted to teach about the ecological crisis.

The teacher educator used self-study methodology to analyze her experiences with local Indigenous leaders when she was a high school social studies teacher and currently as a social studies methods professor. Data sources included journals, field notes, course-related materials, and formal writings.

Through experiences, Indigenous leaders helped the teacher educator identify contrasting cultural paradigms to broaden her understanding of where she lives. This learning enabled the teacher educator to use the two paradigms in her teaching about place and the ecological crisis.

This research shows inner work that can position teacher educators to understand the value of Indigenous wisdom regarding place when teaching about the ecological crisis.

Transient response of continuous composite material (CCM) fin made of high thermally conductive composite material is presented. The continuously varying effective properties of composite material such as thermal conductivity, heat capacity and density have been modelled using the Mori-Tanaka homogenization theory and rule of mixture. Additionally, temperature dependency of thermal conductivity, heat generation (composite materials) and convection coefficient (fluid properties) have also been incorporated. Different base boundary conditions are addressed such as oscillating heat flow, oscillating temperature, step-changing heat flow and step-changing temperature. At the other boundary, the fin is assumed to have a convective tip.

Lattice Boltzmann method is implemented using an in-house source code for obtaining the numerical solution of typical non-linear heat balance equation of the aforementioned problem under various transient base boundary conditions.

The effects of various thermal parameters such as material diffusivity ratio and conductivity ratio, area ratio and Biot number on transient response of fin and temperature distribution of fins are studied and interpreted. The heat transfer rate and time for attainment of steady state temperature of metal matrix composite (MMC) fin are found to be proportionally dependent on their diffusivity ratio. Additionally for higher values of area ratio and biot number, MMC fins are reported to dissipate the heat more efficiently in comparision to homogeneous fins in terms of time required to attain the steady state and surface temperature.

Response of transient fin associated with advanced class of material can facilitates the practicing engineers for designing high-performance and/or miniaturized thermal management devices as used in electronic packaging industries.

Studies of composite fin consisting of laminating second layer of material over the first layer have been reported previously, however transient response of CCM fin fabricated by continuously varying the volume fraction of two materials along the fin length has not been reported till date. Such material finds its application in thermal management and electronic packaging industries. Results are plotted in form of a graph for different application-wise material combinations that have not been reported earlier, and it can be treated as design data.