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A numerical study of heat transfer enhancement due to the deformation of droplets at high Reynolds numbers is described. The two phase‐flow has been computed with a 3D DNS program using the volume‐of‐fluid method. The droplets are deformed because of the surrounding gas stream especially due to a sudden rise of flow velocity from zero to U_i. As the governing non‐dimensional parameter the Weber number of the droplets has been varied between 1.3 and 10.8 by assuming different surface tensions at Reynolds numbers between 360 and 853. The dynamical behavior of the droplets as a function of the Weber and the Ohnsorge number are in good agreement with experimental results from the literature. At the highest Reynolds number Re=853, a significant dependency of Nu on We has been found. The comparison of a Nusselt number computed with the real surface area with a Nusselt number computed with the spherical surface area shows that the heat transfer increases not only due to the droplet motion but also due to the larger surface area of the deformed droplet.

Commenting on the Mexican Revolution in 1938, Trotsky argued that the country might achieve “national independence,” understood as a break with dependency relations. Whether this might occur depended – Trotsky continued – on “international factors.” Though not engaging with Mexico, Antonio Gramsci made a similar theoretical point. It is hence from this perspective that this chapter analyses the Mexican Revolution, asking whether it led to a break in dependency relations and the attainment of “national independence” or what I refer to as “relative geopolitical autonomy.” Presenting a framework of analysis largely based on the work of Gramsci that highlights its continuity with the thought of Marx, the chapter will answer negatively to this question. The chapter starts from the idea that Porfirio Díaz’s regime was unable to adapt the economic structure (still pre-capitalist) to the complex superstructures (capitalist), that is, to realize an historic bloc. It would be this job that the emergent Mexican bourgeoisie sought to finish. However, the situation is complicated by the powerful emergence of social movements from below, constituted largely by landless peasants, and to a lesser extent, the industrial proletariat. I will therefore argue that the revolution has been both “passive” and “bounded.” The term passive revolution will be applied to the last phase of the revolution as the emerging bourgeoisie successfully coopted the demands of the popular masses thereby “passivizing” them. But crucially, the revolution was also “bounded” because international factors, and especially US influence, played a conditioning role throughout the revolutionary process. At the same time, it would be the very “passive” nature of the revolution that would contribute to the reproduction of relations of dependency. Hence the chapter concludes that the period Trotsky commented upon (the Cárdenas period) is the highest level of “independence” Mexico achieved, only to decrease again over the years.

In the coming decades, the aging of European population will continue at a rapid pace. The National Transfer Accounts (NTA) methodology breaks down the income and consumption by age to analyze the impact of population aging on economic sustainability and economy in general. This chapter uses fully comparable results of NTA for 25 European Union countries in 2010 to indicate the potential increase in dependency in the future given the current institutional setting. Next to the conventionally defined demographic dependency ratio, we add (1) the NTA dependency ratio using the age patterns of production and consumption in the market and (2) the National Time Transfer Accounts dependency ratio using age patterns of production and consumption originating from unpaid work that is mostly provided within the households. The authors show that imbalances will originate from the impact of population aging on market part of the economy. Further, some imbalances will also be coming from unpaid work but of much lesser extent.

The systems psychodynamic perspective was used to explore the functioning of a management team at one of the plants of a South African production company experiencing change. The focus was on the impact of social defenses on the leadership style being exercised. During a day long consultation session with the team a dynamic of control and dependency was observed. The transactional culture that can be regarded as “normal,” in this environment, actually became part of a defense strategy, resulting in dependency and a lack of authorization that limited the use of transformational leadership. A lack of clarity in terms of role and boundary definitions furthermore resulted in a struggle in terms of interrelatedness and a lack of interdependent functioning at a system's level.

Linking together four other articles in the journal, this commentary aims to discuss how and why national policy and its implementation in England have helped or hindered a reduction in dependency and increase in independence for people with a learning disability.

The paper is primarily a personal view, drawing on examples from policy, practice and research, written to be challenging and provocative about the current limitations of policy and its delivery mechanisms in the current political and economic climate.

The lack of a clear consensus about “prevention” in the learning disability sector and a failure to give sufficient time to effect cultural change that will help reduce dependency, allied to a set of system dynamics that militate against creative commissioning and the use of evidence, are collectively resulting in effective action to promote independence being limited to places that are characterised by creative thinking and effective leadership.

The paper argues for a fundamental change in the prevailing approach to commissioning and accountability in public services.

The purpose of this paper is to explore the reasons why customers often cannot or do not exit a negative service encounter (lock-in) and to discuss how this affects their well-being and coping responses. This contributes to the research on how negative service encounters emerge and evolve and how such encounters impact customer well-being and subsequent responses.

An inductive, exploratory approach was used. Interviews with 20 service customers yielded over 90 detailed lock-in experiences across 25 different services. A multi-step, iterative coding process was used with a mixture of coding techniques that stem from a grounded theory approach.

Four categories of factors that caused customers to endure a negative event were identified (physical lock-in, dependency on the service, social lock-in and psychological lock-in). Customers either experienced inner turmoil (if they perceived having the option to stay or leave) or felt captive; both impacted their well-being and coping strategies in different ways. Three characteristics of negative events that caused lock-in to persist over time were identified.

This is a qualitative study that aims to identify factors behind customer lock-in, reduced well-being and coping strategies across different types of service encounters. Future research may build on these themes to investigate lock-in during specific service encounters in greater depth.

This research provides insights regarding how service providers can anticipate lock-in situations. In addition, the findings point to several ways in which frontline employees can assist customers with the coping process, during lock-in.

Customer lock-in during a service encounter is a common, yet unexplored phenomenon. This research contributes to a better understanding of why customers endure negative events and how such perceptions are reflected in their experiences and behaviors.

The Edmund Edelman Children’s Court is a juvenile dependency courthouse in Los Angeles designed with bright murals, open play spaces, and modified courtrooms to be “child-sensitive” and “family-friendly.” Through a recounting of the political and cultural forces at play building up to its construction, I argue that the decisions to build a “child-sensitive” court confirm the carceral containment of the culpable black adult. This article represents an inquiry into the cultural logic of the court’s construction, revealing the relationship between raced constructions of innocence and guilt. This study draws from five months of fieldwork conducted in the Edelman Children’s Court.

The evaluation of the haptics of water taps and wear-related changes during usage usually involves time- and cost-intensive testing. The purpose of this paper is to abstract the tribo-system between technical ceramic disks of water tap mixer cartridges to the model level and study the tribological behavior.

The friction and wear behavior was studied by means of an alumina ball-on-original alumina disk setup at different temperatures as well as under dry conditions and under lubrication by different greases. Thereby, the frictional behavior was measured in situ, and the wear losses were analyzed by means of laser scanning microscopy.

It was shown that friction and wear can behave in a contrasting way, whereby one grease might lead to low friction, that is, an easy-going movability of the water tap, but to increased wear losses. The latter, in turn, is an indicator for the usability and service life, which cannot be explained from friction alone. Thereby, the viscosity of the base oil, the grease consistency and additives were identified as relevant grease formulation parameters to allow for fluid film (re-)formation and removal of wear particles.

To the authors’ best knowledge, this is the first approach to systematically analyze the friction and wear behavior of technical ceramic disks of water tap mixer cartridges in dependency on the temperature as well as the used lubricating grease. This approach is relevant for developing screening test strategies as well as for the selection of lubricants for water tap applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0334/

The curved and tribologically highly stressed surfaces of bearing components pose a major challenge for steel alloys or tribological resistant coatings like tetrahedral amorphous carbon (ta-C) coatings which in particular have an increased risk of delamination due to the significantly increased residual stresses. A possibility to prevent coating failure is the use of dopants while maintaining or even increasing tribological properties. This study aims to compare the tribological behavior of several doped diamond-like-carbon coatings with an undoped ta-C coating under varying slip conditions and Hertzian pressure up to 1800 MPa.

For this purpose, the tribological behavior was studied using of a ball-on-disc tribometer and a two-disc test rig under mixed/boundary conditions. The tests were conducted with coated specimens against uncoated 100Cr6 steel. Additionally, the influence of lubrication additives was studied due to the use of two fully formulated PAO-based oils, one without and one with molybdenum containing additives. The friction was measured in situ, and the wear was analyzed trough laser scanning microscopy and tactile measurement.

It was shown that the use of doped ta-C coatings exhibited a tendency for a more favorable tribological behavior compared to undoped ta-C coatings, with no general dependence on the lubricants used. The use of the most suitable coatings reduced the wear of the steel counter-body considerably.

To the best of the authors’ knowledge, this is the first approach of testing the tribological behavior of these doped ta-C coatings, developed for friction efficiency, in dependency on lubrication additives under the given load collective. The approach is relevant to determine whether the friction reduction and the wear inhibition of these coatings are suitable for higher contact pressures and load cycles.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0336/

Induction machines for traction applications are operated at working points of high ferromagnetic saturation. Depending on the working point, a broad spectrum of harmonic frequencies appears in the magnetic flux density of induction machines. Detailed loss analysis therefore requires local and temporal highly resolved nonlinear field computation. This loss analysis can be performed in the post processing of nonlinear transient finite element simulations of the magnetic circuit. However, it takes a large number of transient simulation time steps to build up the rotor flux of the machine.

In this paper, hybrid simulation approaches that couple static FEA, transient FEA and analytic formulations to significantly decrease the number of simulation time steps to calculate the magnetic field in steady state are discussed, analyzed and compared.

The proposed hybrid simulation approaches drastically decrease the simulation time by shortening the transient build-up of the rotor flux. Depending on the maximum error of the rotor flux linkage amplitude compared to the steady state value, a reduction of simulation time steps in the range of 55.5 to 98 per cent is found.

The presented hybrid simulation approaches allow efficient performing of the transient FE magnetic field simulations of induction machines operated as traction drives.