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The purpose of this study is to determine the possibility of an accurate assessment of the spatial distribution of material properties such as conductivities or impedances from boundary measurements when the governing partial differential equation is a Laplacian.

A series of numerical experiments were carefully performed. The results were analyzed and compared.

The results to date show that while the optimization procedure is able to obtain spatial distributions of the conductivity k that reduce the cost function significantly, the resulting conductivity k is still significantly different from the target (or real) distribution sought. While the normal fluxes recovered are very close to the prescribed ones, the tangential fluxes can differ considerably.

At this point, it is not clear why rigorous mathematical proofs yield results of convergence and uniqueness, while in practice, accurate distributions of the conductivity k seem to be elusive. One possible explanation is that the spatial influence of conductivities decreases exponentially with distance. Thus, many different conductivities inside a domain could give rise to very similar (infinitely close) boundary measurements.

This implies that the estimation of field conductivities (or generally field data) from boundary data is far more difficult than previously assumed when the governing partial differential equation in the domain is a Laplacian. This has consequences for material parameter assessments (e.g. for routine maintenance checks of structures), electrical impedance tomography, and many other applications.

This is the first time such a finding has been reported in this context.

Electrical capacitance tomography (ECT) and electrical resistance tomography (ERT) are promising techniques for multiphase flow measurement due to their high speed, low cost, non-invasive and visualization features. There are two major difficulties in image reconstruction for ECT and ERT: the “soft-field”effect, and the ill-posedness of the inverse problem, which includes two problems: under-determined problem and the solution is not stable, i.e. is very sensitive to measurement errors and noise. This paper aims to summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide reference for further research and application.

In the past 10 years, various image reconstruction algorithms have been developed to deal with these problems, including in the field of industrial multi-phase flow measurement and biological medical diagnosis.

This paper reviews existing image reconstruction algorithms and the new algorithms proposed by the authors for electrical capacitance tomography and electrical resistance tomography in multi-phase flow measurement and biological medical diagnosis.

The authors systematically summarize and evaluate various reconstruction algorithms which have been studied and developed in the word for many years and to provide valuable reference for practical applications.

Despite the amount of attention given to social cohesion, divisions within many societies are becoming wider due to various factors including religious and far-right extremism and economic austerity. Given its “wickedness”, social cohesion has been researched from various dimensions. However, to develop an effective solution-based programme, these multi-facets need to be brought together for a clearer way forward. This paper aims to bring together multiple disciplines to propose a way forward in the social cohesion discourse in the following two ways: by developing a common conceptualisation of social cohesion and identifying an effective approach to operationalise social cohesion.

This research adopted a critical qualitative research approach and used three expert discussion forums consisting of academics and practitioners from multiple disciplines.

The research identifies contact theory and participatory approaches as providing an effective way forward for social cohesion. Social cohesion is conceptualised in the form of factors needed to build a cohesive society and outcomes of a cohesive society. Using the social marketing approach of down- mid- and up-stream strategies and interventions, this research proposes a bottom-up approach to addressing the wicked problem of social cohesion.

Social cohesion has been discussed by various academics and practitioners from multiple disciplines. This paper developed a common conceptualisation of social cohesion based on a review of multi-disciplinary literature combined with discussions with experts from academia and practice. Relating this to the down-, up- and mid-stream social marketing, and this paper also identified the participatory approach, based on contact theory, as an effective way in which social marketers can achieve downstream social marketing objectives.

Slowly, and driven by a growing recognition of the impact of organised crime on developing countries, as well as the allure developing countries represent to criminal groups, development agencies have begun to engage with the problem of criminality. As a new actor in this area though, the linkage between development actors and other stakeholders – particularly those at the security end of the spectrum – is mired by a series of tensions. The explicit connection between crime and development in the Sustainable Development Goals increases the incentive, and urgency, for development actors to work through these tensions. However, the response often replicates the focus of security actors, such as building the capacity of law enforcement agencies to arrest criminals and seize illicit goods. This approach neglects the specific value that development offers in the response to organised crime. This chapter will map out the tensions that exist between security and development actors, and their impact on the response to organised crime. It will then consider what development can contribute to the response, drawing on examples from Libya and Mexico.

The purpose of this paper is to help project management (PM) game designers and educators in simulating complexity in PM games and in assessing the effect of simulated project complexity levels on students’ learning experience. To achieve this aim, the authors attempt to design and evaluate two computer-based project crashing games (PCGs) with different complexity levels, namely project crashing game (PCG) and program crashing game (PgCG).

A literature review is conducted to identify serious games design principles. These principles are then manifested in the design of PCG and PgCG. The latter is a more complex version of the first. Students’ reaction after playing both games are then analyzed quantitatively.

The authors discover that students’ learning experience is affected by how complex the simulated project is. The more complex the project is (i.e. as in the PgCG), the more realistic the game is perceived. Nevertheless, the authors also discover that the less complex game (PCG) offers significant value to students, particularly to teach basic PM principles to those with minimum or no practical experience. This game is perceived as better in increasing students’ learning confidence as its content is perceived as more relevant to their existing knowledge.

The authors adopt a project complexity perspective when designing and evaluating the games.

Many neo-Weberians adopt the state’s authority-monopolizing aim as their theoretical expectation. Through a case study of the Peruvian state and Lima’s squatter settlements, I provide evidence in support of the opposite contention: that states may unintentionally produce non-state extractive-coercive organizations. During the mid- to late-twentieth century, Lima’s population grew rapidly. Since they had few economic resources, the new urban poor requisitioned public lands and set up dozens of squatter settlements in the city’s periphery. Other researchers have identified several novel political phenomena stemming from such urban conditions. I focus here on the impact of the state. Using secondary and primary data, I examine three periods during which the state applied distinct settlement policies and one in which it did not apply a settlement policy, from 1948 to 1980. I find that when it applied each of the settlement policies, the state produced non-state political authorities – neighborhood elites – who extracted resources from squatters and tried to control neighborhood turf even against state encroachment, and that the state’s non-involvement did not produce them.

In 2017, the CPA exam added task-based simulations that require candidates to demonstrate analytical, critical thinking, and problem-solving skills. In addition, there has been an evolution in training and learning from face-to-face, synchronistic, group study, to online, asynchronistic, and independent study. These changes suggest the need to reexamine the effectiveness of CPA exam candidates’ study methods. In this study, the authors analyze the degree of use and effectiveness of various study methods (e.g., instructor-led study programs, self-study review courses, flashcards, study notes, and practice problems). Based on a survey of candidates taking the CPA exam in 2018 and 2019, the authors find that the most effective method of study is practicing problems. Opposite the results of some extant research, using an instructor-led study program does not appear to increase the likelihood of passing. Because this is the only study to examine a variety of CPA exam study methods since the 2017 exam changes, its results serve as a benchmark for researchers interested in investigating future changes in study habits.