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This paper aims to increase the knowledge of the run-in process of lubricated contacts in hydraulical pumps. When performing EHL simulations of tribological contacts, the surface influence needs to be taken into account. This experimental measurement wants to investigate the amount of change of the flow factors in the first hour of run of tribological contacts.

An experimental test bench is used to run-in several samples. After several minutes of running, samples are removed and the surface structure is captured using a digital microscope. With the measured data, flow factors are calculated.

The findings were clear that flow factors are highly direction-dependent, especially shear flow factors in radial directions experience almost no change. Overall, influence of the surface structure of up to 30% compared to a flat surface can be registered.

This paper helps to choose application-oriented values for the simulation of tribological contacts.

The purpose of this paper is to show these effects in an abstracted micro gap test bench. Because of stronger emission laws, the ambition to raise the rail pressure in common-rail systems from the current 2500 bar to 3000 bar is a given. The pressure increase will allow fine atomization of fuel and therefore more efficient combustion. But within the technical system of the high-pressure pump, stronger thermal stresses of the piston–cylinder contact are expected. A pressure drop from such a high level causes high temperature gradients due to energy dissipation.

For a detailed examination, the critical piston–cylinder contact has been investigated in an abstracted test bench with a flat parallel gap and an equivalent thermo-elastohydrodynamic simulation model.

The simulation results show good accordance to the measurements of pressures, temperatures and leakages for pressures up to 3000 bar. Comparison with elastohydrodynamic lubrication results outlines the need to consider temperature and pressure effects viscosity and solid deformation for the simulation and design of tribological contacts at high pressures.

This paper describes a simulation method with high accuracy to investigate tribological contacts considering temperature effects on solid structures and the fluid film. The thermo-elastohydrodynamic lubrication simulation method is valid not only for piston–cylinder contacts in high-pressure pumps but also for journal bearings in combustion engines.

People around the world are not sufficiently capable or willing to engage in retirement planning. New technological tools have been proposed as a promising solution to foster involvement and consequently encourage retirement planning. This paper aims to test whether an interactive online pension planner can improve participants’ behaviour, behavioural intentions, attitude, knowledge and perceived ease of use, usefulness and enjoyment.

In collaboration with a company specialised in technologically advanced pension planners, three different versions of an online pension planner were created. The control condition only allowed participants to check their pension situation and the composition of future retirement income. In the medium interactivity level, participants could choose to modify certain variables affecting their pension income, on top of the features from the control. The highly interactive planner additionally included an interactive budget tool and showed whether the accumulated pension income was sufficient to cover the desired spending. Data were collected with the help of an online panel (N = 285).

This paper finds a positive effect of interactivity on behaviour within the planner, that is, the number of clicked options, as well as on participants’ intention to check their personal pension situation in the upcoming three to six months. Moreover, this paper finds gender differences: male participants prefer a high level of interactivity, while women prefer a medium level.

An interesting modification to the current research design would be to use personal, self-relevant data in the online pension planner. Moreover, conducting the study in a computer laboratory could increase concentration on the task, and hence involvement. Next to gender, there might be other factors that possibly influence the results. It would be interesting to investigate other measures of behaviour such as the time spent on the pension planner. Further research should also study the effects of other features that shape user’s perception of interactivity, which include human-to-human interactivity.

The results show that technological services, such as advanced online pension planners, can positively affect engagement with retirement planning. Thus, pension providers are encouraged to use interactive online pension planners. The results with respect to gender suggest tailoring pension planners to match specific preferences of recipients. New service technologies provide novel opportunities to cater to individual differences by, for example, integrating less interactive features for women than for men in a pension planner. Moreover, cognitive involvement should be stimulated by integrating relevant, interesting and valuable information.

Lack of engagement with retirement planning is an important challenge to Western societies. People who do not sufficiently search for information about their expected pension benefits may encounter significant pension gaps resulting in detrimental welfare effects at retirement. This problem is enhanced by the fact that increasingly, the risks and responsibility for retirement planning are being shifted towards pension plan participants themselves. Thus, finding ways to increase engagement with retirement planning by making use of advances in service technologies brings benefits to society.

First, this paper contributes to the customer engagement literature by studying how new technological interfaces improve user experiences, knowledge and engagement within the low involvement context of retirement planning. Second, this paper advances service research by zooming in on customer heterogeneity in using the technology-based online pension planner and studying the moderating effect of involvement and gender more closely. Third, this paper contributes to the financial services literature by studying how new service technologies can help to increase attitudes, knowledge and engagement with retirement planning.

In school improvement studies, randomized experiments are rare. A special problem is the assignment to the experimental and control groups, taking into account the different starting conditions at the schools in terms of school improvement competencies. The purpose of this paper is to take the example of an intervention study conducted in Baden-Württemberg, Germany, the extent to which the challenges involved with a quasi-experimental design were addressed is examined.

The intervention study was conducted with 54 math teachers (experimental group: n=29; control group: n=25) and their grade 7 and 8 classes (n=1,054) at 13 secondary schools. It aimed to increase teacher cooperation on teaching for promotion of students’ self-regulated learning. T-tests, Mann-Whitney tests, ANOVA, multilevel regression analyses were conducted.

At the beginning of the intervention, the teachers in the two groups did not differ significantly in prior cooperation on teaching processes and in attitudes toward cooperation. However, they differed in prior cooperation on school framework conditions and teaching processes. The intervention was effective in increasing teachers’ cooperation intensity on instruction, and teachers’ attitude toward binding cooperation. However, teaching processes did not change depending on experimental or control group.

Teacher cooperation practice was assessed only by teachers’ self-report. No indicators on the quality of the cooperation among teachers were included.

The paper discusses the challenges and limitations of conducting intervention studies on school improvement. Implications for further research are given.

This paper fulfils an identified need to study how quasi-experimental designs can be implemented in intervention studies on school improvement.

This study aims to conceptually propose and empirically validate a path perspective on the servitization process of manufacturing firms. It identifies a customer and an outcome path to servitization, sheds light on the pivotal role of digital technology usage for both value-creating paths and explores their financial and relational performance outcomes.

The authors use a mixed-method approach, combining a qualitative study with a cross-sectional survey in the USA, the UK and Germany.

Manufacturing firms choose between two generic paths to servitization, a customer and an outcome path. Digital technology usage is equally important for both value-creating paths. Progress on the outcome path has a positive effect on firms’ financial performance, whereas the customer path has an indirect effect only, fully mediated by firms’ relational performance. Customer tenure and customer’s open-mindedness are contingency variables in the digital technology usage – servitization path – firm performance framework.

A path perspective is useful to conceptualize the servitization processes in manufacturing industries. Future research should investigate the sequential choice of servitization paths and explore its drivers and performance outcomes.

To create and claim superior value for their customers, managers can choose between two servitization paths, leading to differential performance outcomes. While digital technology usage is key to progress on both paths, it is particularly effective for newly acquired customers on the customer path. Suppliers should target their value-creating service offerings at open-minded customer firms to reap their full performance potential.

Propose and empirically validate a path-perspective on servitization. Understand the pivotal importance of digital technology usage for both servitization paths.

The authors provide primary data on salt iodisation of processed foods in Germany, analyse reasons for food processors' use or non-use of iodisation and derive implications for public health.

Statistical evidence is presented on the use of iodised salt in bread and bakery products, meat and meat products and dairy products in the German grocery-retailing sector. Information is based on mobile data collection in a representative sample of grocery stores in four German cities. These data are analysed with logistic regression models. Additionally, an online survey of bakers and butchers is utilised to record and to explain the use of iodised salt in specialised food stores.

Salt was added in 69.3% of the 29,910 foods analysed in the market study. When salt was added, iodised salt was used in only 28.5% of the cases. According to the online survey, only 44% of the bakers and butchers used iodised salt, and the user share declined over time. Incomplete information from processors on the role of iodised salt for public health is contributing to the low and declining user share.

The authors combine different market research methods and elaborate that the recommendation by the German Federal Ministry of Food and Agriculture – “If salt, then iodised salt” – is implemented to a very limited extent by the food industry and specialised food stores. From the behaviour of food processors and their perceptions of salt iodisation, the authors gain new insights for policy and public health.