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In this paper the authors review the recent numerical techniques proposed to solve the forward and inverse problems concerning the electromagnetic casting and electromagnetic levitation techniques of the metallurgical industry. In addition, the authors present a new topology optimization method to solve the inverse axisymmetric electromagnetic levitation problem.

The proposed method is based on an exact second-order topological expansion of a Kohn–Vogelius-like functional specially devised for this problem.

Through some examples the authors show that it can find suitable solutions efficiently.

The new method completes the set of efficient methods available to solve the inverse electromagnetic casting and the inverse axisymmetric electromagnetic levitation problems.

A new way of solving the steady‐state coupled radiative‐conductive problem in semi‐transparent media is proposed. An angular discretization technique is applied in order to express the radiative transfer equation (RTE) in an inhomogeneous system of linear differential equations associated with Dirichlet boundary conditions. The system is solved by a direct method, after diagonalizing the characteristic matrix of the medium. The RTE is coupled with the nonlinear heat conduction equation. A simulation of a real semi‐transparent medium composed of silica fibers is illustrated. Comparison with results of other methods validates the new model. Moreover, the general scheme is easy to code and fast. The algorithm proved to be robust and stable.

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is presented. Emphasis is placed on a new understanding of the key elements (for example, tapes, bumps, inner lead bonding, testing and burn‐in on tape‐with‐chip, encapsulation, outer lead bonding, thermal management, reliability and rework) of this rapidly moving technology.

This paper aims to discuss the electromagnetic scattering characteristics of the afterbody model with two drag plates.

The plane shape of the drag plate model is designed as a rectangle. High-precision unstructured grid technology is used to treat the target surface. A calculation method based on multiple tracking and dynamic scattering module is presented to calculate the radar cross section (RCS).

The results show that under the given observation conditions, the RCS and surface scattering characteristics of a single drag plate change with the increase of the opening angle, which makes the forward RCS of the afterbody model change more than 8.43 dBm2. The opening of two resistance plates at different fixed angles has little effect on the peak value and position of the RCS of the afterbody model. The dynamic deflection of the two drag plates can bring 16.78 dBm2 fluctuations to the forward RCS of the afterbody model, and more than 25.59 dBm2 fluctuations to the side RCS.

The installation positions of the drag plate on the aircraft are various, so the method in this paper can provide reference and support for RCS analysis of the speed brake at other positions.

The presented calculation method is of engineering value to analyze the electromagnetic scattering characteristics of the drag plate.

The purpose of this study is to design a plasmonic structure that can be used simultaneously as a heater and a refractive index sensor applicable for heating and sensing cycles of lab-on-chip (LOC).

The authors report on the full optical method applicable in the heating and sensing cycles of LOC based on the plasmonic nanostructure. The novelty of this proposed structure is due to the fact that a structure simultaneously acts as a heater and a sensor.

In terms of the performance of the proposed structure as an analyte detection sensor, in addition to the real-time measurement, there is no need to labeling the sample. In terms of the performance of the proposed structure as a plasmonic heater, the uniformity and speed of the heating and cooling cycles have been greatly improved. Also, there is no need for experts and laboratory conditions; therefore, our proposed method can meet the conditions of point of care testing.

The authors confirm that this work is original and has not been published elsewhere nor it is currently under consideration for publication elsewhere.

Plastic pollution is a widespread problem around the world. However, the problem is more severe and ever increasing in developing countries. The literature suggests that the majority of the work and the solutions that have been proposed to address plastic littering have been undertaken in developed countries. Thus, there is a need to explore the problem in developing countries to better understand the issue and to develop context-specific solutions. We explored the norms perspective using ‘The Focus Theory of Normative Conduct’, individual ethical position and place attachment factors. Interviews were conducted in Pakistan with 16 people who were recently at a beach at which there was a large amount of plastic litter. Results showed that people are influenced by the pro-littering social norms of their friends and neighbours. However, people with strong anti-littering personal norms are not influenced by pro-littering social norms. We also found that people have varying moral position, and their lack of attachment with the public place also influences their littering behaviour. Moreover, people believe that other people litter due to lack of education and awareness, lack of garbage bins and a general level of carelessness. Future research needs to focus on activating an individual's idealist moral position and an individuals' attachment with the place to enhance the activation of anti-littering personal norms which will help reduce littering behaviour. Further still, government needs to set up campaigns at public places to create awareness among people about the impact of littering, and government also needs to improve the effectiveness and efficiency of waste management. Businesses can also play a role by providing waste bins which may be used as a source of promoting their support for reducing litter.

The goal of this paper is to give a comprehensive and short review on how to compute the first- and second-order topological derivatives and potentially higher-order topological derivatives for partial differential equation (PDE) constrained shape functionals.

The authors employ the adjoint and averaged adjoint variable within the Lagrangian framework and compare three different adjoint-based methods to compute higher-order topological derivatives. To illustrate the methodology proposed in this paper, the authors then apply the methods to a linear elasticity model.

The authors compute the first- and second-order topological derivatives of the linear elasticity model for various shape functionals in dimension two and three using Amstutz' method, the averaged adjoint method and Delfour's method.

In contrast to other contributions regarding this subject, the authors not only compute the first- and second-order topological derivatives, but additionally give some insight on various methods and compare their applicability and efficiency with respect to the underlying problem formulation.

This paper provides a self-contained introduction to the mathematical aspects of the topological derivative.

Full justifications are given on simple model problems following a modern approach based on the averaged adjoint state technique. Extensions are discussed in relation with the literature on the field.

Closed expressions of topological derivatives are obtained and commented.

Several cases are covered in a unified and didactic presentation. Some elements of proof are novel.

The purpose of this research is to empirically test the role of psychological contract breach in explaining the relationship between leadership style and procedural justice, burnout and psychological distress. This study provides important insights for police agencies who seek to positively impact, through the actions of their leaders, on both performance and psychological health of their officers. Drawing from the study findings, key recommendations for police leadership development programs are made.

The current study with a large sample of Australian police (N = 1763), explores the relationship between leader-member exchange (LMX) leadership style and two sets of outcomes. The first is procedural justice, an important job performance outcome related to police practice. The second outcome includes two measures of psychological health, specifically burnout and psychological distress. Psychological contract breach (PCB) is investigated in the current research as a potential mediator in the relationship between leadership and (a) job performance and (b) psychological health.

Using mediated regression analyses, high LMX leadership is associated with lower PCB, higher procedural justice and reduced psychological health impairment amongst staff. The relationship between LMX and procedural justice was fully mediated by PCB, meaning that PCB explains the relationship between LMX and procedural justice. Partial mediation was found for both psychological health outcomes. As such, leadership style has a direct relationship with psychological health, and is partly explained by PCB.

Very little research has considered the role of PCB in explaining how leadership style is related to job performance and psychological health outcomes in policing. To our knowledge, this is the first study that has empirically examined whether leadership style makes it more likely that a police officer will perceive PCB. And further, whether this breach is associated with reduced job performance (i.e. less procedural justice) and poorer psychological health (i.e. increased burnout and psychological distress).

Automated body condition scoring (BCS) through extraction of information from digital images has been demonstrated to be feasible; and commercial technologies are being developed. The primary objective of this research was to identify the factors that influence the potential profitability of investing in an automated BCS system.

An expert opinion survey was conducted to provide estimates for potential improvements associated with technology adoption. A stochastic simulation model of a dairy system, designed to assist dairy producers with investment decisions for precision dairy farming technologies was utilized to perform a net present value (NPV) analysis. Benefits of technology adoption were estimated through assessment of the impact of BCS on the incidence of ketosis, milk fever, and metritis, conception rate at first service, and energy efficiency.

Improvements in reproductive performance had the largest influence on revenues followed by energy efficiency and then by disease reduction. The impact of disease reduction was less than anticipated because the ideal BCS indicated by experts resulted in a simulated increase in the proportion of cows with BCS at calving 3.50. The estimates for disease risks and conception rates, obtained from literature, however, suggested that this increase would result in increased disease incidence. Stochastic variables that had the most influence on NPV were: variable cost increases after technology adoption; the odds ratios for ketosis and milk fever incidence and conception rates at first service associated with varying BCS ranges; uncertainty of the impact of ketosis, milk fever, and metritis on days open, unrealized milk, veterinary costs, labor, and discarded milk; and the change in the percentage of cows with BCS at calving 3.25 before and after technology adoption. The deterministic inputs impacting NPV were herd size, management level, and level of milk production. Investment in this technology may be profitable but results were very herd‐specific. A simulation modeling a deterministic 25 percent decrease in the percentage of cows with BCS at calving ≤3.25 demonstrated a positive NPV in 86.6 percent of 1,000 iterations.

This investment decision can be analyzed with input of herd‐specific values using this model.