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THE Deutsche Versuchsanstalt für Luft‐fahrt—known for short as the D.V.L.—at Berlin‐Adlershof, is the central establishment for aeronautical research in Germany. Hitherto the D.V.L. had as its special prerogative the testing of aircraft and aero‐engines for certificates of airworthiness. Since April 1, 1933, the Inspection Department has passed under the authority of the “Reichsamt für Flugsicherung” (Air Security Board), but it has not actually been separated from the D.V.L., continuing to have its premises at the D.V.L. establishment. (Further details of the Inspection Department are given later.)

A reconsideration of some Austrian work in public finance analysis that is based on a positive theory of the state and its relationship with the market economy is offered. The contributions of some prominent Austrian economists are considered, and how they relate to contemporary thinking in public finance. The two central paradigms of the tax state and entrepreneurship are explored.

Numerous metals can be processed using the additive manufacturing process laser-based powder bed fusion of metals (PBF-LB/M, ISO/ASTM 52900). The main advantages of additive manufacturing technologies are the high degree of design freedom and the cost-effective implementation of lightweight structures. This could be profitable for gears with increased power density, combining reduced mass with considerable material strength. Current research on additively manufactured gears is focused on developing lightweight structures but is seldom accompanied by simulations and even less by mechanical testing. There has been very little research into the mechanical and material properties of additively manufactured gears. The purpose of this study is to investigate the behavior of lightweight structures in additively manufactured gears under static loads.

This research identifies the static load-carrying capacity of helical gears with different lightweight structures produced by PBF-LB/M with the case hardening steel 16MnCr5. A static gear loading test rig with a maximum torque at the pinion of T₁ = 1200 Nm is used. Further focus is set on analyzing material properties such as the relative density, microstructure, hardness depth profile and chemical composition.

All additively manufactured gear variants show no failure or plastic deformation at the maximum test load. The shaft hub connection, the lightweight hub designs and the gearing itself are stable and intact regarding their form and function. The identified material characteristics are comparable to conventionally manufactured gears (wrought and machined), but also some particularities were observed.

This research demonstrates the mechanical strength of lightweight structures in gears. Future research needs to consider the dynamic load-carrying capacity of additively manufactured gears.

Of significance for patents information during the past decade or so have been the major changes in patents legislation, improvements to the publications of the principal patenting systems, and the transforming effects of computerized databases. The review covers these changes and outlines the current publication procedures of the European Patent Convention, Patent Cooperation Treaty, and the major national systems. The importance of the patent specification as a source of information, and developments during this period in its construction and bibliographic data are explained. Official and non‐official publications associated with the specification are covered. Particular emphasis is given to computer databases covering patents, since they now form a powerful, numerous and growing means of searching specifications in the majority of subject fields. Reference is made to efforts to increase general awareness of the value of patents as information and to improve their availability by schemes such as the UK's Patents Information Network.

This account aims to introduce contrasting perspectives on teaching and learning methods, and to detail the growth of new forms and vocabularies of access to learning. As we move towards the new millennium, the development of national, yet diversified, credit frameworks and systems will provide an essential underpinning for the organisational culture that will be needed to sustain the wellbeing and growth of the educational system. These new systems are already being incorporated into the practice of ‘virtual’ education. Lifelong learning has widespread support across the social and political spectrum and its importance can hardly be over‐stated as we seek to maintain competitiveness in a changing world. Increasing knowledge and understanding to serve both the needs of the economy and of individuals to play a major role in democratic life has become an agenda of necessity as well as desire. An open society requires open systems of knowledge. A prognosis for the future is submitted where the significance of part‐time modular and open flexible learning is evaluated in terms of a curriculum rooted in useful knowledge and competences, acquired at different sites of learning, including the workplace. It is argued that modular structures, using the potential offered by credit accumulation and transfer to different institutions with different missions, can transcend and transform the learning opportunities for students in a mass system of higher education which is rapidly becoming part of a global market economy and society. Continuous lifelong learning involving its key features of open access, recognition of learning wherever it takes place and the growth of new learning networks and partnerships, is at the conceptual heart of the development of the virtual university.

Bearings in field applications with high dynamic loading, e.g. wind energy plants, suffer from sudden failure initiated by subsurface material transformation, known as white etching cracks in a typical scale of μm, preferably around the maximum Hertzian stress zone. Despite many investigations in this field no precise knowledge about the root cause of those failures is available, due to the fact that failure under real service conditions of wind energy plants differs from what is known from test rig results in terms of contact loading, lubrication or dynamics. The purpose of this paper is to apply Barkhausen noise measurement to a full bearing test ring running under conditions of elastohydrodynamic lubrication (EHL) with high radial preload.

Full bearing tests are carried out by use of DGBB (Deep Grove Ball Bearings) with 6206 specification, material set constant as 100Cr6, martensitic hardening, 10‐12 percent maximum retained austenite and radial preload of 3500 MPa. Speed is set 9000 rpm, temperature is self setting at 80°C by test conditions. For tests, synthetic hydrocarbon base oil (Poly‐α‐Olefine) with a 1 percent amount of molydenum‐dithiophosphate (organic chain given as 2‐ethylhexyl) was used.

Non‐destructive fractal dimension analyses by use of Barkhausen noise measurements is of versatile value in terms of recording bearing manufacturing processes, but can also be part of non‐destructive condition monitoring of bearings in field applications, where predictive reactive maintenance is crucial for availability of the plant.

Barkhausen noise signal recording may also be valuable for case studies related to microstructure changes of steel under operation conditions. Bearings are exposed in plenty of conditions to phenomena such as straying currents, subsequently straying magnetic fields. Hardly anything is known about how microstructure of bearing steel is susceptible to such conditions. This will be part of further studies.

Results given in the paper show that sudden bearing failure, according to formation of subsurface material property changes might be driven by activities of dislocations. Since those activities start with sequences of stress field‐induced formation of domains, later by formation of low‐angle subgrains, and at least phase transformation, recording of the Barkhausen signal would lead to real predictive condition monitoring in applications where a highly dynamic loading of the contact, even with low nominal contact pressure leads to sudden failure induced by white etching.

The purpose of this paper is to provide a differentiated view of relationship‐specific proactive improvement of logistics service providers (LSPs) that distinguishes between the cost and performance and the effect that these two dimensions of innovation have on three distinct customer loyalty dimensions (retention, extension, and referrals).

A confirmatory empirical study was conducted based on social exchange theory and customer value theory. The survey responses from 298 firms were analysed using structural equation modelling and multi‐group analysis to test for direct effects and moderation.

Both dimensions of relationship‐specific proactive improvement by LSPs (cost and performance) are strong drivers of all three customer loyalty dimensions and, thus, are important to customer relationship management and relevant areas to be considered within innovation management. The effect on customer loyalty is moderated by the dynamism of the customer's market. Proactive cost improvements are more important under high dynamism, while proactive performance improvements, contrary to initial assumptions, are more important when dynamism is low.

Future studies should analyse other cultural settings, differentiate between functional and relationship value provided, consider other services, investigate how LSPs can facilitate proactive improvement and improve innovation management, and explore how customers can foster proactive improvement.

The currently low level of proactive improvement should be increased if LSPs want to enhance customer loyalty. In doing so, LSPs ought to consider the dynamism of their customers' markets.

The paper is the first to provide a differentiated view on the role of relationship‐specific proactive innovation that distinguishes between cost and performance improvements and illustrates their effects on three distinct customer loyalty dimensions.

Because of the major contribution of logistics to the greenhouse gas effect, logistics research has begun to address the topic of energy, but it has not yet targeted the role of energy within logistical decision-making processes. To facilitate such endeavors, the purpose of this paper is to explore the perceptions of energy which managers in logistics organizations portray.

This investigation is based on interviews with 17 managers. The findings are embedded in the theory of planned behavior (TPB) and stakeholder theory (SHT).

The study depicts initial insights on which energy-related perceptions exist, how they can be categorized into attitudes, subjective norms, and perceived behavioral controls (PBCs), and how different stakeholders seem to affect them.

This research suggests a tentative comprehensive conceptual framework that describes the role of energy in logistical decision-making processes. The findings on attitudes and subjective norms appear to be unspecific to the logistics domain, whereas some of the PBCs are presumably unique to the logistics context. Future logistics research should hence focus its efforts on the PBCs. Generalizability and completeness of the managerial perceptions must be validated by future research.

The findings help logistics organizations in scrutinizing managerial perspectives on energy and in developing awareness-raising measures.

The behavioral perspective applied in this study can complement extant, more technically oriented views. The conceptual framework that integrates the TPB and SHT may also be useful for organizational research beyond the logistics domain.