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The most important advance in system design is the development of modeling and simulation methods to predict complex performance before prototypes are developed. New systems are developed in a spiraling approach; as more is learned about the system, design changes are proposed and evaluated. This approach allows the engineering team to “spin out” early versions of the system for preliminary evaluation, permitting changes to be made to the system design without incurring unacceptable cost. Because of the complexity of human performance, current modeling techniques provide only a first approximation. However, it has been demonstrated that even simple, inexpensive modeling approaches are useful in uncovering workload and performance problems related to developing systems (Barnes & Beevis, 2003). More important, these models can serve as the basis for operator simulation experiments that verify and also calibrate the original models. Furthermore, early field tests and system of systems demonstrations that can validate these results under actual conditions are becoming an increasingly significant part of the early design process. Fig. 1 illustrates this interdependence indicating a spiraling process throughout the design starting with simple predictive methods and progressing to more expensive validation methods. These iterations should continue until most of the soldier's variance is accounted for, and before any formal soldier testing is conducted. Fig. 1 presents the ideal combination of techniques; not all systems can be evaluated this thoroughly but more cost-effective modeling and simulation tools combined with realistic field exercises should make this approach more the norm as future unmanned systems are developed (Barnes & Beevis, 2003). In the remainder of this chapter, several case studies are presented to illustrate how the techniques in Fig. 1 have been applied in UAV programs.

The term rancid is used to describe either objectionable odours or tastes in many food products. In this article P.J. Barnes PhD and T. Galliard DSc, FRSC, FIFST outline the causes, methods of measurement and ways of preventing rancidity in foods.

We conduct an experiment to examine the occurrence of the bystander effect on willingness to report a fraudulent act. Specifically, we investigate the impact of evidence strength on managers’ decisions to blow the whistle in the presence and absence of other employees who have knowledge of the wrongdoing. Results indicate that when there is strong evidence indicating a fraudulent act, individuals with sole knowledge are more likely to report than when others are aware of the fraudulent act (the bystander effect). However, the bystander effect is not found when evidence of fraud is weak. Further, a mediated moderation analysis indicates that perceived personal responsibility to report mediates the relation between others’ awareness of the questionable act and reporting likelihood, suggesting that the bystander effect is driven by diffusion of responsibility. Our results have implications for all types of organizations that wish to mitigate the detrimental effect of fraud. Specifically, training or incentives may be necessary to overcome the bystander effect in an organization.

This chapter explores a set of principles that underpin ensuring that the learning needs of all students are addressed in next generation learning spaces. With increasingly diverse higher education environments and populations, higher education needs to move from seeing student diversity as problematic and deficit-based, to welcoming, celebrating and recognising diversity for the contributions it makes to enhancing the experience and learning outcomes for all students. The principles of Universal Design for Learning (CAST, 2011) provide a framework for high-quality university teaching and learning, as well as guidance on the multiple methods and means by which all students can be engaged and learn in ways that best suit their individual styles and needs. An inclusive approach is important pedagogically and applies to both the physical and virtual environments and spaces inhabited by students. When the design of physical environments does not incorporate universal design principles, the result is that some students can be locked out of participating in campus or university life or, for some, the energy required to participate can be substantial. With the digital education frontier expanding at an exponential rate, there is also a need to ensure that online and virtual environments are accessible for all. This chapter draws on the relevant research and the combined experience of the authors to explore an approach to inclusive practices in higher education next generation learning spaces and beyond.

Malnutrition is widespread and affects about one-third of humanity. Increasing production and consumption of vegetables is an obvious pathway to improve dietary diversity, nutrition and health. This chapter analyses how climate change is affecting vegetable production, with a special focus on the spread of insect pests and diseases. A thorough literature review was undertaken to assess current global vegetable production, the factors that affect the spread of diseases and insect pests, the implications caused by climate change, and how some of these constraints can be overcome. This study found that climate change combined with globalization, increased human mobility, and pathogen and vector evolution has increased the spread of invasive plant pathogens and other species with high fertility and dispersal. The ability to transfer genes from wild relatives into cultivated elite varieties accelerates the development of novel vegetable varieties. World Vegetable Center breeders have embarked on breeding for multiple disease resistance against a few important pathogens of global relevance and with large evolutionary potential, such as chili anthracnose and tomato bacterial wilt. The practical implications of this are that agronomic practices that enhance microbial diversity may suppress emerging plant pathogens through biological control. Grafting can effectively control soil-borne diseases and overcome abiotic stress. Biopesticides and natural enemies either alone or in combination can play a significant role in sustainable pathogen and insect pest management in vegetable production system. This chapter highlights the importance of integrated disease and pest management and the use of diverse production systems for enhanced resilience and sustainability of highly vulnerable, uniform cropping systems.

ALTHOUGH numerous papers and lectures presented to the Royal Aeronautical Society have mentioned the upward trend in turbine inlet gas temperatures, there has been no review of the status of blade cooling technology since 1956, when Ainley's classic paper ‘The High Temperature Turbo‐jet’ was published. Accordingly it is the aim of this paper to present such a review. Before doing so it is worth while to compare the engine situation today with what it was in 1956. At that time, much of the available experience in the U.K. on air cooled turbines was based on experimental units, designed for the express purpose of measuring blade temperatures under controlled conditions of cooling airflow and high gas temperature. These research turbines had also yielded some useful preliminary data on the aerodynamic effects of cooling air discharge and on thermal stress and creep problems. Some engine experience had been attained, mainly (in the U.K.) with engines such as the Avon, Conway and Tyne. Whereas many of the research turbine and cascade blades had fairly complex patterns of relatively small cooling passages, the blades which had been submitted to engine running usually had a few comparatively large passages. Rotating blades were made exclusively by forging and extrusion processes from wrought nickel‐base alloys. Some nozzle guide vanes were cast.

Inspired by the high-friction performance of the soft toe pads of tree frogs, this study aims to investigate the effect of elastic deformation on the lubrication properties of squeezing films inside soft tribocontacts with microstructured surface under wet conditions.

A one-dimensional hydrodynamic extrusion model was used to study the film lubrication characteristics of conformal contact. The lubrication characteristics of the extruded film, including load-carrying capacity, liquid flow and surface elastic deformation, were obtained through the simultaneously iterative solution of the fluid-governing and deformation equations.

The results show that the hydrodynamic pressure is approximating parabolically and symmetrically distributed in the contact area, and the peak value appears in the center of the extrusion surface. Elastic deformation increases the thickness of the liquid film, weakens the bearing capacity and homogenizes the liquid flow rate of inside soft friction contact. The magnitude of this effect greatly increases as the initial liquid film thickness decreases. Moreover, the elastic deformation directly affects the average film thickness of the extrusion contact. Narrow and shallow microchannels are found to result in a more prominent elastic deformation on the microstructured soft surface.

These results present a design for soft tribocontacts suitable for submerged or wet environments involving high friction, such as wiper blades, in situ flexible electrons and underwater robots.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2024-0049/

This chapter addresses adaptation to dynamic, novel and uncertain military environments. These environments require a shift from a maneuver warfare paradigm to an asymmetric world where shifting alliances, questionable civilian loyalties, opaque cultures, and the requirement to maintain peace one day and combat the next makes for a particularly confusing situation. This new warfare paradigm requires adaptation to an uncertain, complex environment.

The initial section discusses a general cognitive model of visualization called RAVENS and its importance for adaptation developed specifically to address complex military environments. RAVENS posits that humans are inherently flexible decision makers and situation awareness depends on the ability of humans to create narrative visualizations that capture the overall context of complex military environments. Using the framework as a guideline, we will examine two important visualization research programs whose purpose is to allow military operators to rapidly adapt to volatile situations. The first program investigates cognitive effects such as the framing bias and their possible interactions with a variety of display concepts during a series of missile defense simulations. The experimenters presented risk as a spatial representation of uncertainty and target value that emphasized either expected population lost or expected population saved. The second program investigated the feasibility of using visualizations generated from Scheherazade (a coevolutionary algorithm) to aid MI analysts in predicting emergent tactics of terrorist groups during urban operations. Finally, we discuss the value of these approaches for providing coherent narrative understanding as called for in the RAVENS model.

This article is an attempt to discuss pigments used in the paint, printing ink, plastics and rubber industries in a general way, prior to their more detailed description by specialists in the subsequent articles in this issue of the journal.