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This paper aims to address the influence of tribofilms and running-in on failures and friction of gears. The operation regime of gears is increasingly shifted to mixed and boundary lubrication, where high local pressures and temperatures occur at solid interactions in the gear contact. This results in strong tribofilm formation due to interactions of lubricant and its additives with the gear flanks and is related to changes of surface topography especially pronounced during running-in.

Experiments at a twin-disk and gear test rig were combined with chemical, structural and mechanical tribofilm characterization by surface analysis. Pitting lifetime, scuffing load carrying capacity and friction of ground spur gears were investigated for a mineral oil with different additives.

Experimental investigations showed a superordinate influence of tribofilms over surface roughness changes on damage and friction behavior of gears. Surface analysis of tribofilms provides explanatory approaches for friction behavior and load carrying capacity. A recommendation for the running-in of spur gears was derived.

Experimental methods and modern surface analysis were combined to study the influence of running-in and tribofilms on different failures and friction of spur gears.

Besides other approaches, fuel savings in automotive applications and energy savings, in general, also require high‐efficiency gearboxes. Different approaches are shown regarding how to further improve gearbox efficiency. This paper aims to address these issues.

The paper takes the following approach: theoretical and experimental investigations of bearing arrangements and gear design as well as lubricant type and lubricant supply to the components lead to efficiency optimisation.

No‐load losses can be reduced, especially at low temperatures and part‐load conditions when using low‐viscosity oils with a high viscosity index and low oil immersion depth or low spray oil supply of the components. Bearing systems can be optimised when using more efficient systems than cross‐loading arrangements with high preload. Low‐loss gears can contribute substantially to load‐dependent power loss reduction in the gear mesh. Low‐friction oils are available for further reduction of gear and bearing mesh losses. All in all, a reduction of the gearbox losses in an average of 50 per cent is technically feasible.

Results from different projects of the authors and from the literature are combined to quantitatively evaluate the potential of power loss reduction in gearboxes.

A failure mode called “flank breakage” is increasingly observed in cylindrical and bevel gears. Up to now, there was no calculation method available to determine the load‐carrying capacity related to flank breakage in bevel gears. Therefore, a research project was initiated to investigate the described failure mode in bevel gears and to develop a calculation method to predict the risk of flank breakage of such gears. The purpose of this paper is to describe this project.

The presented research project contained: determination of the decisive influence parameters in experimental investigations with bevel gears; development of a model to explain flank breakage in bevel gears; and development of a calculation method and design rules to avoid flank breakage.

In systematic tests, the influenced parameters of flank breakage were investigated. Besides the load torque, especially the case depth and the core hardness turned out as decisive parameters. A higher sulfur concentration in the material does not seem to be critical. The analysis of damage patterns of test and practical gears showed that the initiating crack always started below the surface in the region of the transition from case to core. For unidirectional loading, the crack propagates to the active flank on the one side and to the tooth root on the other side. On the basis of these findings, a local and a simplified calculation method were developed to estimate the risk of flank breakage.

With the described calculation method, it is now possible to evaluate running gears according to their risk of flank breakage and design new gears with a sufficient safety factor to avoid this failure.

The purpose of this paper is to make an attempt to evaluate the pitting load carrying capacity under increased thermal conditions. This is the basis for an estimated lifetime which is one of the most important parameters defining transmission reliability.

Recommendations related to pitting load carrying capacity calculation of case hardened gears running at high gear bulk temperatures are formulated. These factors are based on extensive experimental data, obtained in pitting tests with high oil injection temperatures, high oil sump temperatures or high operational gear bulk temperatures due to a lack of heat dissipation caused by minimised lubrication.

Testing of gear type C‐PT on FZG back‐to‐back test rig at high gear bulk temperatures by either heating up the lubricant or caused by a lack of heat dissipation as it appears with poor lubrication conditions resulted in a decrease of up to 30 per cent of the endurance strength in various investigations. This results in a reduction of the material strength due to tempering effects and high surface shear stress due to low oil film thicknesses caused by low operating oil viscosities.

The present calculation method in the standard DIN/ISO is not valid for high gear bulk temperatures. Nevertheless, the present calculation algorithms of the standards DIN/ISO are valid for low and moderate thermal operating conditions when using oil temperatures of up to 80 (90)°C in the case of a sufficient cooling oil supply to the gear mesh. With the presented modifications higher gear bulk temperatures (>120°C) can be taken into account.

This paper aims to add further evidence to adoption criteria for “revolutionary” business techniques.

Adoption criteria for business techniques with a high degree of novelty have been developed earlier. The case of exchange-traded funds supports the earlier findings. The methodology applied is explicative.

The analysis supports findings that an effective response to a problem, the availability of a controllable procedure, the means to apply the procedure easily and the hardware jointly explain adopting “revolutionary” business techniques.

The results of case studies, in general, do not permit induction. More research might identify additional adoption criteria or falsify the presently obtained results. Therefore, further research is invited.

Managers seeking or being introduced to new techniques in business administration might use the criteria outlined here for their evaluation.

The author believes this paper corroborates earlier findings on adopting “revolutionary” business techniques that draw on theoretically developed technologies.

The purpose of this paper is to assess the effectiveness of event-related sports sponsorship and ambushing activity using social media video advertising that aim to affect spectators’ implicit and explicit brand information processing.

A dual model of brand knowledge is used that considers the implicit and explicit information processing of marketing-induced brand messages. A web study was conducted prior to the 2014 FIFA World Cup. Each participant implicitly and explicitly evaluated either one sponsor brand or one ambush brand before and after watching the video advertisement (within-subject design). A Wilcoxon signed-rank test was used to evaluate each change of the pre-post testing scores.

Implicit and explicit brand associations as well as brand behavior were partially affected by the short contact with the advertisements of sponsor brands and ambush brands. In this regard, the implicit association measurements were more sensitive to reveal changes in the brand knowledge structure than their explicit counterparts. Furthermore, sponsorship advertising was slightly more effective than ambush advertising.

The current exploratory study evaluated for the first time the performance of event-related video advertisements that were originally released on social media of sponsor brands and ambush brands. The findings emphasize the necessary requirement of evaluating the implicit processing in addition to the explicit processing of sponsorship information to ensure a holistic evaluation of consumers’ memory with regard to the effectiveness of a sponsorship activity.

Increased business competition requires even more rapid and sophisticated information and data analysis. These requirements challenge performance management to effectively support the decision making process. Business analytics is an emerging field that can potentially extend the domain of performance management to provide an improved understanding of business dynamics and lead to a better decision making. The purpose of this positional paper is to introduce performance management analytics as a potential extension of performance management research and practice. The paper clarifies the possible application areas of business analytics and their advantages within the context of performance management.

The paper employs a literature based analysis and from this a conceptual argument is established. Finally, a business analytical model is presented to be used to undertake future research.

The paper clarifies the possible application areas of business analytics and their advantages within the context of organizational performance management.

The main implication is that the paper provides evidence of the use of business analytics for understanding organizational performance. Several insights are provided for management accounting research and education.

This paper examines the determinants of corporate dividend policy in Jordan. The study uses a firm‐level panel data set of all publicly traded firms on the Amman Stock Exchange between 1989 and 2000. The study develops eight research hypotheses, which are used to represent the main theories of corporate dividends. A general‐to‐specific modeling approach is used to choose between the competing hypotheses. The study examines the determinants of the amount of dividends using Tobit specifications. The results suggest that the proportion of stocks held by insiders and state ownership significantly affect the amount of dividends paid. Size, age, and profitability of the firm seem to be determinant factors of corporate dividend policy in Jordan. The findings provide strong support for the agency costs hypothesis and are broadly consistent with the pecking order hypothesis. The results provide no support for the signaling hypothesis.

This paper aims to investigate the scuffing load‐carrying capacity of three gear oils: a standard mineral lubricant containing extreme pressure and anti‐wear additives (M0) and two biodegradable saturated esters containing low toxicity additives (E1 and E2).

Four‐ball wear tests were performed, according to standard ASTM D4172. Results from the wear scar diameter and from ferrographic analysis of the test oil samples are presented and related to the lubricant properties. The physical, chemical and biodegradability properties of the lubricants are presented and compared.FZG gear scuffing tests were performed, according to standard DIN 51535, in order to evaluate the scuffing load‐carrying capacity of the two oils. Two reference tests were performed, A20/16.6/90 and A10/16.6/90.

Test results include scuffing load stage, maximum oil bath temperature, pinion weight loss and surface roughness measurement of the teeth flanks.

The paper provides information on the scuffing load‐carrying capacity of three gear oils.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.