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The purpose of this study is to provide a micromixer for achieving effective mixing of two liquids. The mixing of two liquids is difficult to achieve in microfluidic chips because they cannot form turbulence at small dimensions and velocities.

In this paper, four kinds of passive micromixers based on splitting–recombination and chaotic convection are compared. First, a better E-shape mixing unit based on the previous F-shape mixing unit has been designed. Then, the E-shape mixing units are further combined to form three micromixers (i.e. E-mixer, SESM and FESM).

Finally, the mixing experimental results show that the mixing indexes of E-mixer, SESM and FESM are more than those of F-mixer when the Reynolds number range is from 0.5 to 100. And at Re = 15, the lowest mixing index of E-mixer is 71%, which is the highest of the four micromixers.

At Re = 80, the highest mixing index of F-mixer and E-mixer is 92 and 94 per cent, respectively, and then it begins to decrease. But the mixing index of SESM and FESM remains close to 100 per cent.

Eddy current testing (ECT) is widely used in the non-destructive evaluation of materials in different industries. In this paper, ECT has been used to detect the presence of cracks in boiler tubes. The most important feature in ECT is the way in which the eddy currents are induced and detected in the sample. The authors have tried to design a new sensor that is effective in detecting cracks in boiler tubes. The purpose of this paper is to study the response of this sensor to cracks of different depths and dimensions.

The designed eddy current sensor is equipped with an exciting and a sensing coil. An alternating current is passed through the exciting coil thus producing eddy currents. The sensing coil scans the outer surface of the boiler tube and looks for abrupt changes in output signals resulting from sharp discontinuities in structure.

The sensor designed can detect the position of the crack. The presence of crack is indicated by a reduction in the induced voltage in the sensing coil. The sensor is also used for characterisation of the cracks, and can distinguish between cracks of varying shape, size and depth. The sensitivity of the sensing coil to cracks is dependent on operating conditions, such as frequency and voltage of the excitation signal.

The new sensor designed is used to detect defects in boiler tubes in power plants. However, the operating conditions, such as excitation frequency and amplitude will vary with composition of the boiler tubes.

The new eddy current sensor designed for crack detection is an E-shaped core coil. The shape of the coil provides a high permeability path to the magnetic field lines, thus reducing the loss of the field produced. This helps in improving the sensitivity of the coil, and makes the detection system effective in detecting hairline cracks.

This paper aims to report the results of numerical analysis of turbulent fluid flow and forced-convection heat transfer in solar air channels with baffle-type attachments of various shapes. The effect of reconfiguring baffle geometry on the local and average heat transfer coefficients and pressure drop measurements in the whole domain investigated at constant surface temperature condition along the top and bottom channels’ walls is studied by comparing 15 forms of the baffle, which are simple (flat rectangular), triangular, trapezoidal, cascaded rectangular-triangular, diamond, arc, corrugated, +, S, V, double V (or W), Z, T, G and epsilon (or e)-shaped, with the Reynolds number changing from 12,000 to 32,000.

The baffled channel flow model is controlled by the Reynolds-averaged Navier–Stokes equations, besides the k-epsilon (or k-e) turbulence model and the energy equation. The finite volume method, by means of commercial computational fluid dynamics software FLUENT is used in this research work.

Over the range investigated, the Z-shaped baffle gives a higher thermal enhancement factor than with simple, triangular, trapezoidal, cascaded rectangular-triangular, diamond, arc, corrugated, +, S, V, W, T, G and e-shaped baffles by about 3.569-20.809; 3.696-20.127; 3.916-20.498; 1.834-12.154; 1.758-12.107; 7.272-23.333; 6.509-22.965; 8.917-26.463; 8.257-23.759; 5.513-18.960; 8.331-27.016; 7.520-26.592; 6.452-24.324; and 0.637-17.139 per cent, respectively. Thus, the baffle of Z-geometry is considered as the best modern model of obstacles to significantly improve the dynamic and thermal performance of the turbulent airflow within the solar channel.

This analysis reports an interesting strategy to enhance thermal transfer in solar air channels by use of attachments with various shapes

This paper aims to examine the direct and indirect effects of substitutes for leadership on performance outcomes.

A self‐report questionnaire was distributed to a sample of 177 Australian local council employees. The responses were analysed using ICLUST analysis and hierarchical multiple regression analysis.

The results indicated significant positive effects of some substitutes for leadership on performance outcomes. Furthermore, some substitutes for leadership moderated the effects of transactional leadership behaviours on performance outcomes, whereas another sub‐component of substitutes for leadership moderated the effects of social processes of leadership on performance outcomes. In addition, some substitutes for leadership partially mediated the relationship between transformational leadership and performance outcomes.

The cross‐sectional design of the study reduces the capacity to draw definitive causal inferences.

The current study supports the view that council leaders could have influenced the employees' attitudes, perceptions, and performance by indirectly shaping the environment in which the subordinates worked (i.e. shaping task and organisational characteristics). The study implies the need for leaders in the local councils to understand those substitutes for leadership that mediate the influence of transformational leadership (such as group and work design capacities) and how they can be managed to enhance employee performance outcomes.

This is one of the first Australian studies to comprehensively examine the influence of substitutes for leadership on performance outcomes.

In recent years, the use of high performing materials, and application of additive manufacturing technology for industrial production has witnessed a steady rise and its expanse is only to increase in the future. “Selective laser melting (SLM) technique” for an exotic nickel-titanium (NiTi) shape memory alloy (SMA) is expected to a great facilitator to research in this area. The purpose of this paper is to put forth the research direction of NiTi shape memory alloy by selective laser melting.

This review also summaries and skims out the information on process equipment, adopted methodologies/strategies, effects of process parameters on important responses e.g. microstructure and comprehensive functional and mechanical properties of SLM-NiTi. In particular, the functional characteristics (i.e. shape memory effects and super-elasticity behavior), process analysis and application status are discussed.

Current progresses and challenges in fabricating NiTi-SMA of SLM technology are presented.

This review is a useful tool for professional and researchers with an interest in the field of SLM of NiTi-SMA.

This review provides a comprehensive review of the publications related to the SLM techniques of NiTi-SMA while highlighting current challenges and methods of solving them.

This paper aims to explore human technology relations through the lens of sci-fi movies within the life cycle of the ETHICOMP conference series. Here, different perspectives on artificial intelligent agents, primarily in the shape of robots, but also including other kinds of intelligent systems, are explored. Hence, IT-ethical issues related to humans interactions with social robots and artificial intelligent agents are illustrated with reference to: Alex Proyas’ I, Robot; James Cameron’s Terminator; and the Wachowski brothers’ Matrix. All three movies present robots cast in the roles of moral agents capable of doing good or evil. Steven Spielberg’s Artificial Intelligence, A.I. gives rise to a discussion of the robot seen as a moral patient and furthermore reflects on possibilities for care and trust relations between robots and humans. Andrew Stanton’s Wall-E shapes a discussion of robots as altruistic machines in the role as facilitators of a flourishing society. Steven Spielberg’s Minority Report allows for a discussion of knowledge-discovering technology and the possibility for balancing data utility and data privacy.

Observations of themes in sci-fi movies within the life span of the ETHICOMP conference series are discussed with the purpose of illustrating ways in which science fiction reflects (science) faction. In that sense, science fiction does not express our worries for a distant future, but rather casts light over questions, which is of concern in the present time.

Human technology interactions are addressed and it is shown how sci-fi films highlight philosophical questions that puzzle us today, such as which kind of relationships can and ought to be formed with robots, and whether the roles they play as social actors demand that one ought to assign moral standing to them. The paper does not present firm answers but instead pays attention to the selection and framing of questions that deserve attention.

To relate sci-fi movies to topics raised during the past 20 years of the ETHICOMP conference series, seemed to be an appropriate way of celebrating the 20-year anniversary of the ETHICOMP conference series.

As stated in the United Nations Global Assessment Report 2022 Concept Note, decision-makers everywhere need data and statistics that are accurate, timely, sufficiently disaggregated, relevant, accessible and easy to use. The purpose of this paper is to demonstrate scalable and replicable methods to advance and integrate the use of earth observation (EO), specifically ongoing efforts within the Group on Earth Observations (GEO) Work Programme and the Committee on Earth Observation Satellites (CEOS) Work Plan, to support risk-informed decision-making, based on documented national and subnational needs and requirements.

Promotion of open data sharing and geospatial technology solutions at national and subnational scales encourages the accelerated implementation of successful EO applications. These solutions may also be linked to specific Sendai Framework for Disaster Risk Reduction (DRR) 2015–2030 Global Targets that provide trusted answers to risk-oriented decision frameworks, as well as critical synergies between the Sendai Framework and the 2030 Agenda for Sustainable Development. This paper provides examples of these efforts in the form of platforms and knowledge hubs that leverage latest developments in analysis ready data and support evidence-based DRR measures.

The climate crisis is forcing countries to face unprecedented frequency and severity of disasters. At the same time, there are growing demands to respond to policy at the national and international level. EOs offer insights and intelligence for evidence-based policy development and decision-making to support key aspects of the Sendai Framework. The GEO DRR Working Group and CEOS Working Group Disasters are ideally placed to help national government agencies, particularly national Sendai focal points to learn more about EOs and understand their role in supporting DRR.

The unique perspective of EOs provide unrealized value to decision-makers addressing DRR. This paper highlights tangible methods and practices that leverage free and open source EO insights that can benefit all DRR practitioners.

Food guides are graphic representations of food-based dietary guidelines that support national health policies and programming. They are visual aids simplifying complex nutritional messaging for the public. While pyramid and circle formats are the most common shapes in use worldwide, the dinner plate format is increasing in use due to its perceived effectiveness. However, research examining visual attributes of food guide graphics, and the dinner plate model specifically, is limited. The purpose of this paper is to systematically compare and analyse key visual attributes of plate food guide graphics (across multiple examples) to assess their potential for effective visual communication of nutrition messaging.

This study engages in a qualitative analysis of compositional elements of food guide graphics. Data collection and analysis are grounded in the methods of compositional interpretation, which includes a qualitative, descriptive approach to establishing a thematic survey of the data.

Unique visual attributes of the plate food guide (including image content, spatial organisation and expressive content) present challenges in the communication of key nutritional messaging regarding proportionality, moderation and overall usability.

A better understanding of the visual attributes of the plate food guide model will contribute to improved design and development of this key public health tool by researchers, educators and health practitioners. Additionally, the examination of visual attributes has implications for the study of food guide understanding and use.

This study highlights the need for critical visual skills in qualitative health research, and to address gaps in health education more broadly.

The paper aims to give the reader a consolidated state of art in the full‐wave modeling of passive interconnection systems using equivalent circuits and presents several advantageous techniques developed by the authors.

The paper presents the theory of generalized partial element equivalent circuit (PEEC) modeling in the frequency domain (FD) and time domain (TD) developed by the authors. The widely spread simplified approaches are derived from this general formulation and the most important issues (e.g. stability in the TD) are considered. The theoretical part is completed by a simulation example, which shows the efficiency of studied methods.

Novel approaches for co‐simulation of passive interconnections in their circuit environment.

The PEEC method is widely used in the practice of computational electromagnetics, e.g. by the authors in the practical electromagnetic compatibility simulation.

The paper is based on the original work of authors carried through over many years.