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The purpose of this paper is to develop accurate model and simulation of mechanical power transmission within roller‐screw electromechanical actuators with special attention to friction, compliance and inertia effects. Also, to propose non‐intrusive experiments for the identification of model parameters with an integrator or system‐oriented view.

At system design level, the actuation models need to reproduce with confidence the energy losses and the main dynamic effects. The adopted modelling methodology is based on non‐intrusive measurements taken on a standard actuator test‐bench. The actuator model is first structured with respect to the bond‐graph formalism that allows a clear identification of the considered effects and associated causalities for model implementation. Various approaches are then combined, mixing blocked or moving load, position or torque control and time or frequency domains analysis. The friction representation model is suggested using a step‐by‐step approach that covers a wide domain of operation. The model is validated under varying torque and speed conditions.

A structured model is introduced with support of the bond‐graph formalism. Combining blocked/moving load and time/frequency domain experiments allows the development of progressive model identification. An advanced friction representation model is proposed including the effects of speed, transmitted force, quadrant of operation and roller‐screw preload.

Mechanical transmission energy losses and dynamics are modelled in a system‐oriented view without massive need to confidential design parameters. Not only speed but also load and operation quadrant effects are reproduced by the proposed friction model. The non‐intrusive experimental procedure is made consistent with use of a standard actuator test‐bench.

This paper aims to propose preliminary design models of actuator housing that enable various geometries to be compared without requiring detailed knowledge of the actuator components. Aerospace actuation systems are currently tending to become more electrical and fluid free. Methodologies and models already exist for designing the mechanical and electrical components, but the actuator housing design is still sketchy.

The approach is dedicated to linear actuators, the most common in aerospace. With special attention paid to mechanical resistance to the vibratory environment, simplified geometries are proposed to facilitate the generation of an equivalent formal development. The vibratory environment imposes the sizing of the actuator housing. Depending on the expected level of details and to vibration boundary conditions, three levels of modeling have been realized.

This paper shows that the vibrations induced by aircraft environment are not design drivers for conventional hydraulic actuators but can be an issue for new electromechanical actuators. The weight of the latter can be optimized through a judicious choice of the diameter of the housing.

This approach is applied to a comparison of six standard designs of linear actuator geometries after validation of the consistency of the different models. Early conclusions can be drawn and may lead to design perspectives for the definition of actuator architecture and the optimization of the design.

This paper has demonstrated the importance of the vibratory environment in the design of linear actuator housing, especially for electro-mechanical actuators with important strokes. Developed analytical models can be used for the overall design and optimization of these new aerospace actuators.

To develop structured guidelines for the synthesis of dynamic force simulators that are required for the testing of high speed aerospace actuators. To provide realistic and proven solutions at both test bench hardware and control design levels.

The state of the art in control design applied to load simulators in mainly based on complex controllers and does not take into account practical considerations. The objective of the present work is to provide generic preliminary design rules to ensure that the test bench architectures (frame, power transmission and control) and the components specifications are consistent with the targeted performance. Once selected the appropriate power transmission architecture, a linear approach is used as a foundation to generate design rules. Then, preliminary design is achieved thanks to the introduction, as early as possible, of the unavoidable technological defects.

A step‐by‐step methodology allows the designer to select the controller architecture and to specify components with special care to their consistency with the required dynamic performance. The linear then practical approach generates key rules that can be used in the very early phase of the test bench design.

Practical considerations on the components static and dynamic limitations are introduced progressively to make the natural test bench performance as consistent as possible with the performance requirements. Consequently, the controller becomes simpler to design and robust.

Disaster management agencies are mandated to reduce risk for the populations that they serve. Yet, inequities in how they function may result in their activities creating disaster risk, particularly for already vulnerable and marginalized populations. In this article, how disaster management agencies create disaster risk for vulnerable and marginalized groups is examined, seeking to show the ways existing policies affect communities, and provide recommendations on policy and future research.

The authors undertook a systematic review of the US disaster management agency, Federal Emergency Management Agency (FEMA), examining its programs through a lens of equity to understand how they shape disaster risk.

Despite a growing commitment to equity within FEMA, procedural, distributive, and contextual inequities result in interventions that perpetuate and amplify disaster risk for vulnerable and marginalized populations. Some of these inequities could be remediated by shifting toward a more bottom-up approach to disaster management, such as community-based disaster risk reduction approaches.

Disaster management agencies and other organizations can use the results of this study to better understand how to devise interventions in ways that limit risk creation for vulnerable populations, including through community-based approaches.

This study is the first to examine disaster risk creation from an organizational perspective, and the first to focus explicitly on how disaster management agencies can shape risk creation. This helps understand the linkages between disaster risk creation, equity and organizations.

As part of the V.10 F programme financed by Service Technique de la Production Aeronautique (STPA), AEROSPATIALE and DASSAULT — BREGUET have joined forces to produce a single Falcon 10 wing entirely made of carbon fibre. This wing has just been sent from the AEROSPATIALE Company's Nantes factory to the Toulouse Aernautic Testing Centre. A second wing will also be built, but this time, by DASSAULT‐BREGUET Biarritz plant. The two wings will be used for static fatigue testing. The programme calls for another pair of wings, one to be made by each of the same firms. They will later be mounted to a Falcon 10 for flight testing.

The current work reviews all retailing articles published in four prominent retailing journals – Journal of Retailing, Journal of Retailing and Consumer Services, International Journal of Retail & Distribution Management, and International Review of Retail, Distribution and Consumer Research – in the 2009-2015 period, picking up where Runyan and Hyun (2009) left off. The purpose of this paper is to identify leading authors and institutions in retailing research based on overall impact.

Content analysis/literature review/descriptive research.

In total, 1,392 articles were published during this time period, and through a procedure of weights and adjustments for author count, journal impact, journal quality, and journal publishing opportunity, the findings reveal that research collaboration is highly prevalent, as evidenced by the high number of multi-authored papers and cross-university/international partnerships. Additionally, some authors and institutions remain influential, while others have emerged as highly influential in the last seven years. This shows the dynamic nature of the field and the need to remain active in quality publishing.

Scholars must understand that several factors influence impact judgments, which cannot be assessed using raw counts alone. Journal quality, impact, and publishing opportunity as well as author counts are important elements to consider.

These reviews are vital to the field in that they provide status updates on scholarship, so these reviews should be done periodically. Additionally, the findings in this paper provide a more holistic understanding of research impact and permit better assessment for scholars and administrators.

Some of Henryk Grossman's contributions to Marxist economic theory are familiar. Ignorance and misinformation about his life has accompanied and sometimes underpinned widespread criticism of his account of economic crises and neglect of his other work. Grossman's life and work before he moved to Frankfurt am Main in 1925 and wrote his best known publications are therefore outlined, highlighting his deep and active involvement in the Jewish social democratic movement in Galicia before and in the Polish Communist movement after the First World War.