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The purpose of this paper is to study the influence of friction phenomenon generated by a disc brake on the dynamic behaviour of a one-stage spur gear.

A theoretical model is proposed and is based on both theories of Coulomb and Dahl in order to analyse the influence of disc brake friction phenomenon on the dynamic behaviour of one-stage spur gear transmission.

The influence of brake friction on the dynamic behaviour of the transmission is investigated using the proposed model and leads to observe higher vibration levels when the braking is occurring as well as the emergence of significant efforts at the gear teeth.

A new numerical model based on the implicit numerical integration technique of Newmark coupled with Newton-Raphson method is proposed to study the influence of friction phenomenon of a disc brake on the dynamic behaviour of one-stage spur gear.

This paper deals with coupled electromagnetic, hydrodynamic and mechanical motion phenomena in magnetorheological fluid devices. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. In order to include non‐linearity, the Newton‐Raphson process has been adopted. A prototype of an electromagnetic brake has been built at the Poznań University of Technology. The method has been successfully adapted to the analysis of this brake. The results of the analysis are presented.

This paper deals with coupled electromagnetic, hydrodynamic and mechanical motion phenomena in magnetorheological fluid brakes. The governing equations of these phenomena are presented. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. A computer program based on this algorithm was used to simulate the transients in a prototype of magnetorheological brake. The results of the calculations and measurements are presented.

Deals with coupled electromagnetic, hydrodynamic, thermodynamic and mechanical motion phenomena in magnetorheological fluid brake. Presents the governing equations of these phenomena. The numerical implementation of the mathematical model is based on the finite element method and a step‐by‐step algorithm. In order to include non‐linearity, the Newton‐Raphson process has been adopted. The method has been successfully adapted to the analysis of the coupled phenomena in the magnetorheological fluid brake. Present the results of the analysis and measurements.

The purpose of this paper is to elaborate upon the mathematical model of coupled electromagnetic, fluid dynamic and motion phenomena that will allow for investigation of the magnetic hysteresis influence on the axial symmetry magnetorheological fluid (MRF) clutch operation.

To solve the partial differential equations describing magnetic vector and fluid velocity potential distributions in axial symmetry MRF electromechanical transducers the finite‐element methods have been applied. To solve model equations in the time domain, the time stepping method have been adopted. To introduce magnetic hysteresis phenomenon to presented approach the Jiles‐Atherton model have been applied. The physical properties of MRFs have been modeled by means of the Bingham model. Owing to high nonlinearity of the considered problem to solve obtained matrix equations systems the iterative Newton‐Raphson combined with the block over relaxation method have been applied.

The proposed model of coupled phenomena and the elaborated algorithm for solving the nonlinear model equations can be successfully applied in the analysis of transients in the MRF transducers taking fluid dynamics and magnetic hysteresis into account. Comparison of the measured and calculated clutch characteristics proves the model accuracy. Moreover, it has been shown that the residual magnetic flux density of the ferromagnetic core has significant impact on both to yield stresses forming in MRFs as well as the torque in disengagement clutch operation.

Development of the method for analysis of transients electromagnetic and fluid flow phenomena in MRF transducers taking magnetic hysteresis, electric circuits and motion into account. The presented approach is universal and can be successfully applied in other types of MRF electromechanical transducers such as clutch, brakes, rotary and linear dampers.

This study aims to investigate disclosure of asbestos-related liabilities in corporate accounts and counter-accounts to examine whether and how accounting contributes to corporate accountability for asbestos-contaminated products.

This study uses the Goffmanesque perspective on impression management to examine instances of concealed asbestos-related liabilities in corporate accounts vis-à-vis the revealing of such liabilities in counter-accounts.

The findings show counter-accounts provide significant information on liabilities originating from the exposure of employees and consumers to asbestos. By contrast, the malleability of accounting tools enables companies to eschew accounting disclosures. While the frontstage positive performance of companies served an impression management role, their backstage concealing actions enabled companies to cover up asbestos-related liabilities. These companies used three categories of mechanisms to avoid disclosure of asbestos-related liabilities: concealing via a “cloak of competence”, impression management via epistemic work and a silent strategy of concealment frontstage with strategic reorganisation backstage.

This study has policy relevance as regulators need to consider the limits of corporate disclosures as an accountability tool. The findings may also initiate academic and practitioner conversations about accounting standards for long-term liabilities.

This study highlights the strategies companies use both frontstage and backstage to avoid disclosing asbestos-related liabilities. Through analysis of accounts and counter-accounts, this study identifies the limits of accounting as an accountability tool regarding asbestos-induced diseases and deaths.

Although there is no likelihood of mankind running out of energy in the foreseeable future, the immediate danger—pressing for remedial action—is its shortage in the form we are traditionally accustomed to using. To combat this danger, governments of most industrial countries have embarked on a series of strategies. The main targets of most of these are the savings of wasted (rejected) energy, as for instance that wasted in space heating systems through insufficient insulation or in thermal cycles of machinery.

The purpose of this paper is to examine the relationship between management education, the performance of German engineering enterprises and the strategic knowledge status of the executives running those enterprises.

The paper is based upon the results of an online/posted self‐administered questionnaire conducted within Germany, augmented by micro case studies.

Findings suggest that the curricula in German Engineering Faculties fail to fully embrace business and management studies, in particular strategic management which has virtually no presence. Engineers dominate senior management positions within the German machinery and equipment sector yet they display limited knowledge of strategic management tools. There is also evidence that links performance with the application of management knowledge.

The study is limited to senior executives within German SMEs from the machinery and equipment sector. It is likely that the findings would be applicable throughout the German engineering industry; however, generalisability to other countries may be limited. Only a single year's performance (2007) was considered and this is also a limitation of the study. This was mitigated by a request that anomalies be noted, such as extraordinary write offs or a windfall profit, within the year in question, this was then taken into account during the analysis.

Based on the findings it is suggested that German faculties of engineering should enhance and expand management education, particularly strategic management, thus enhancing future performance potential within German SMEs.

This paper examines the level of management education attained by senior engineering executives with a key economic industrial sector in Germany, as such it is one of few such studies which investigates the link between management education and performance.

The 26th International Aerospace Show at Le Bourget will undoubtedly be the largest that has ever been held. Inevitably, at a time when the European industries are attempting to consolidate their positions and the United States industry is pushing hard to improve its own sales and technical standing throughout the world, there will be a highly competitive air about the whole Exhibition. At the same time, many companies will be emphasizing their international links—in terms of collaborative developments, licence production or sales. Organized by the French equivalent of the S.B.A.C. in Britain—the Union Syndicate des Industries Aeronautiques et Spatiales—this year's Salon will follow traditional lines in that each day of the Show will be devoted to a particular facet of aerospace activities thus: June 10 Press Preview; June 11 Official Inauguration by President de Gaulle; June 12 Philately; June 13 Light, Executive and Commercial Aviation; June 14 Space Activities; June 15 Electronics; June 16 Systems and Equipment; June 17 Rotor craft; June 18 French and Foreign Missions; June 19 International Air Display; and June 20 International Flying Display. The Russians will send a number of space exhibits as well as a selection of civil aircraft—including the world's largest helicopter. The British industry will be represented by approximately fifty companies as well as Ministry of Aviation, Ministry of Defence and S.B.A.C. presentations. This preview of the show is concerned solely with the British exhibits, beginning with the major airframe and engine industries.

Here is the long‐awaited fourth edition of Ralph De Sola's classic Abbreviations Dictionary. This updated edition of a work first published in 1958 is the largest, most complete compilation of its kind — a reference book far surpassing all others in the field. Mr. De Sola has expanded his work to include more than 130,000 definitions and entries — over 77,000 definitions, over 54,000 entries. The current edition offers abbreviations, acronyms, anonyms, contradictions, initials and nicknames, short forms and slang shortcuts, and signs and symbols covering disciplines which range from the arts to the advanced sciences and embrace all areas of human knowledge and activity.