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The paper aims to provide an approach to actively decrease the radiation of acoustic noise in synchronous machines.

Splitting regular three‐phase windings of synchronous machines into two independent three‐phase systems allows for an active influence of the current waveform if both winding systems are mutually displaced against each other. The harmonics content of each phase‐current varies due to the mutual inductive coupling with participating currents of both systems. Therefore, the ensuing force‐density distribution on the stator teeth varies accordingly. Resulting structure dynamics and furthermore the radiation of relevant harmonics of the acoustic noise are based on the mechanical excitation of considered force‐density distributions.

Configurations of mutual displacement of phase windings of both winding systems with significant decrease of mechanical deformation and emitted acoustic noise are found. Simulation methods to entirely describe and prove the behavior described are developed.

The proposed approach is developed for a particular synchronous machine. Other machine types are conceivable for analysis in the same manner. Tools need to be adapted. Universal and reliable statements regarding acoustic behavior depend on the mechanical restraint of the machine and may therefore vary.

Active force‐density distribution is used for the noise reduction of alternators in vehicle applications. Additionally, wind‐power generators are considered for the application of split stator winding systems to actively counteract inhomogeneous force distributions on the rotor, evoked by stalling of the propeller blades during pole passing.

Active force‐density modification by stator winding modifications allows for the decrease of noise radiation of electrical machines with rotating‐field windings. Innovative simulation methods developed may now replace prototyping partially.

This paper aims to assess to what extent South American countries have integrated recommendations of the international agenda to address human mobility in the context of disasters and climate change in their national laws and policies.

This research sought to find the level of discussions around human mobility in disaster laws, NDCs and National Adaptation Plans (NAPs) by looking for a range of search terms connected to human mobility in the context of disasters and climate change, followed by the content analysis of these terms.

Some advances with regards to human mobility are already confirmed in the domestic level of South American countries through humanitarian visas to disaster displaced persons and the inclusion of the topic in the DRR, climate change laws, NAPs and INDCs/NDCs. But they have not developed specific strategies with regards to it. Hence, their advances still require that national norms and policies are harmonized with the international guidelines. This will enable to fill the protection gap of people in context of disasters and climate change.

The results assess the level of harmonization above-mentioned between international instruments with national policies on human mobility in the context of disasters and climate change in South America.

In this paper, two transform methods, the Fourier transform (FT) and the wavelet transform (WT) methods, are utilized to process moiré fringes for the strain analysis of electronic packaging. With the introduction of fringe carriers, those transform techniques need only one fringe pattern for each deformation state. The strain modulation to the carrier frequency can be subtracted by filtering as the pattern is transformed into spectrum domain by the fast‐FT processing, and the deformation field can thus be restored by the inverse FT transform after spectral shifting. The WT method expands the pattern information involved in the fringe carrier in both spatial domain and spectral domain to analyze the deformation distribution in this combined space. By changing the transform scales in the processing, the wavelet transform offers multi‐resolution analysis for the deformation field with high gradients.

This chapter analyzes the role of public libraries in providing access to information to Internally Displaced Persons (IDPs) in Nigeria. It examines some of the challenges experienced by the public library system in ensuring equitable access to information to such disadvantaged groups. It also looks at the concept of social exclusion in the context of public library services in Nigeria and how it can be tackled.

The study employed a survey method; data were collected through the administration of structured questionnaires to the study population.

Outcomes from the study point to a need for the development of a policy framework by the National Library of Nigeria and increased partnership between public libraries and other stakeholders in formulating more proactive strategies toward meeting the information needs of IDPs in the affected communities.

Implications from the findings of the study provide a basis by which more proactive measures can be taken toward intervention by public libraries and other stakeholders in the community.

Few studies on the public library in Nigeria have focused on addressing problems of disadvantaged groups in the society. This chapter has examined the fundamental role public libraries can play in confronting the social exclusion of IDPs and also provided useful insights to the nature of their information needs in their given context.

The purpose of this study is to investigate what resources recent refugees to the USA tap into and how collaborative expressive movements were experienced with regard to coping and resourcing, and to derive a theoretical model that would inform the use of dance/movement therapy and other holistic treatment modalities with refugees.

A total of 13 refugees overall participated in parts of this study. Ten of these refugees completed movement sessions and semi-structured in-person interviews. Constructivist grounded theory methods and descriptive statistics were used to analyze the data.

The findings suggest that refugees draw on a number of resources. The collaborative movement experiences seemed to have both a settling and mobilizing effect with the most important phenomenon of connection to the self or to another person. A grounded theory model, developed based on the findings, shows a dynamic interaction between the encountered categories.

The findings are preliminary and not transferrable because of limited size and potential researcher bias.

The findings contribute to an understanding of the resettlement and acculturation phase of refugees with potential implications and suggestions for current clinical practices and health services.

This study was original in its focus on understanding the role and the potential of body and expressive movement among refugees who have experienced trauma. Adherence to transformative paradigm principles invited participants to become co-researchers.

Uninterruptible Power Supply (UPS) systems are typically designed to provide power to computers for five to thirty minutes after all utility company power has failed. In addition to providing blackout and brownout protection, many UPS systems also protect against spikes, surges, sags, and noise, and some also offer many of the features found in power distribution units (PDUs). The major components or subsystems of a typical UPS system are detailed, and a sample bid specification is appended. Three sidebars discuss UPSs and air conditioning, the maintenance bypass switch (MBS), and literature for further reading.

This paper aims to focus on three-dimensional (3D) numerical simulation of a monitored urban underground road consisting of diaphragm walls supported by one row of temporary steel struts and a cover slab in the central area. In addition to the lateral wall displacements, the analysis focuses on the load development in the struts and the evolution of the total stresses at the soil–wall interface, and highlights the 3D effect on the behavior of the structure.

Computation by back-analysis has become an important contribution to the understanding of observed phenomena. In this context, this paper investigates a full 3D numerical back-analysis of diaphragm wall deformation using the finite difference code FLAC3D.

The instrumentation allows a deep understanding of the ground response and the soil-structure interaction phenomena. It also provides an opportunity to validate numerical models. Using a soil model with simple failure criteria, the wall displacements are strongly influenced by the soil deformation modulus. The strut stiffness considerably influences the wall behavior. The geometrical effects have a significant impact on the induced wall displacements.

In the present study, the main soil geotechnical characteristics were deduced from laboratory and in situ tests. However, Young’s modulus of the soil has been adjusted to take account of the unloading effect. In the same context, the non-linearity of the elastic characteristics of the steel struts has been taken into account by modeling the struts using their experimental stiffness instead of their theoretical rigidity.

High-pressure die casting is one of the manufacturing techniques used for the rational mass production of metal parts. Due to the high velocity of the molten metal during the injection phase, the die casting of aluminum is so complex and it is almost impossible to calculate these exact performances. Numerical simulation is an effective way to optimize the injection phase and minimize air entrapment that causes porosity defects in the metal. Generally, the filling phase of the molten metal in the shot sleeve is neglected in most scientific work. This phase is followed by a rest period to allow the escape of the resident air bubbles (gravity effect). The paper aims to discuss these issue.

It is relatively clear that the model described poses a great challenge for numerical implementation, especially for 3D geometries. The governing transport equations are solved numerically using the commercial CFD solver Fluent and the equations are discretized using a pressure-based finite volume method. The coupling pressure–velocity was solved by the PISO algorithm. The PISO algorithm takes relatively more CPU time per solver iteration, but it significantly decreases the number of iterations required for the convergence of the transient flow problems. Laminar flow inside air and molten metal was assumed. In order to describe the behavior of the molten metal, a VOF model has been activated. The model makes it possible to account for the moving boundary due to the variation of the shot sleeve volume caused by the plunger displacement. The scheme used in the discretization of momentum equation was the first-order upwind scheme, and the scheme used for the pressure was the PRESTO. The profile of the plunger velocity, boundary conditions change with time and the physical properties change with liquid fraction were used by implementation of a user-defined function. For the discretization of the domain, an unstructured mesh with triangular elements is used. After conducting mesh sensitivity study, a mesh having 53,813 triangular elements has been chosen for the present study. The convergence criterion was set equal to 10–4 for all parameters.

The results show that the rest and global filling times increase by 2.5 and 8.57 percent with decreasing the pouring velocity by 10 percent. In addition, the rest and global filling times decrease by 5.77 and 8.12 percent with increasing the pouring velocity by 10 percent.

After the filling phase, it is necessary to offer a rest period before the injection phase. However, the rest and global filling times increase by 2.5 and 8.57 percent with decreasing the pouring velocity by 10 percent. In addition, the rest and global filling times decrease by 5.77 and 8.12 percent with increasing the pouring velocity by 10 percent. Increasing the pouring velocity by 10 percent leads increasing of the molten metal velocity in the shot sleeve and requires a delay of time of the beginning of the faster plunger movement by 7–10.5 percent. On the other hand, Figure 12 shows that increasing the pouring velocity requires increasing of the plunger velocity during the injection phase, thus increasing the pouring velocity. In order to overcome this problem, it is necessary to reduce the injection velocity and prolong the period of the slower plunger movement.

The purpose of this paper is to develop an efficient numerical method to study the complex crack initiation and propagation in linear elastic multiphase composites.

A phase field method is developed to study the complex fracture behavior in multiphase composites. A damage threshold is introduced for referring crack initiation in the proposed method. The damage threshold is assigned as a material property so that different composite components possess different thresholds. In this manner, smooth transition from crack initiation to propagation is revealed.

The proposed method is used to investigate complex crack evolution in mesoscale cementitious composite, which consists of aggregates, matrix and void pores. From a mesoscale point of view, it is found that cracks prefer to evolve within the matrix phase. As a crack encounters an aggregate, it tends to bypass the aggregate and evolve along the interface. Cracks tend to avoid to penetrate through aggregates. Also, cracks tend to be attracted by void pores. From a mesoscale point of view, it is revealed that the elastic modulus and strength of concrete models are closely related to porosity.

A criterion with a damage threshold is introduced to the proposed method. The criterions with and without a damage threshold are compared with each other in details. The proposed method is proven to be a useful tool to study mechanical behavior and crack evolution of brittle multiphase composites.

Policy is key for effective displacement governance in times of crises and in response and recovery. Therefore, this study assessed if Australian climate, disaster and emergency management policies provide effective mechanisms for governing displacement crises and areas where current approaches could be improved.

This study assessed 18 national and state-level disaster, emergency and climate change management frameworks to determine if best practice displacement governance themes were reflected in policy documents. Deductive thematic analysis was undertaken using Braun and Clarke’s six-phase method.

Issues of displacement are reflected in policies analysed in this study. However, current policy frameworks need to be equipped to comprehensively address the housing requirements of displaced people or provide long-term initiatives. Approaches are focused on crisis management rather than pre-emptively planning for displacement response and recovery. Therefore, Australia has not exercised national responsibility for displaced people appropriately.

Disaster displacement is an under-researched area of Australian scholarship and disaster management policy and practice. Therefore, this paper has practical implications in so far as it draws attention to the issue of displacement in Australia. A limitation of this paper is that it only analysed policy frameworks specific to disasters. While broader engagement was outside the scope of this study, this limitation provides opportunities for further research from disciplinary perspectives of public housing and homelessness to examine displacement policy challenges in these fields. Furthermore, this study is limited to a theoretical inquiry into this topic through a desktop review of policy documents. While this is a necessary first step, empirical studies are required to determine accurate displacement rates, drivers and people’s experience of being displaced.

This research aims to inform policy by presenting recommendations for policy interventions for disaster displacement governance. Therefore, this research has practical implications as policy and disaster risk reduction (DRR) professionals can draw from the findings of this research when planning and initiating disaster response for displaced persons.

This research draws attention to an area of disaster management practice and policy that has not been adequately accounted for. Highlighting gaps in current policy can assist in developing targeted strategies and solutions for internally displaced people, which protect their rights and meet their needs.

Displacement is a growing climate change issue. This research aims to help address this problem by drawing attention to areas where Australian disaster management approaches fail to account for displaced populations. Therefore, this research has practical implications for addressing future issues of disaster injustice that may arise if displacement continues, unacknowledged in disaster management.