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The experimental modal analysis requires good knowledge of various engineering fields, such as mechanical vibrations, transducers used in vibration measurement, transducers and system calibration methods, data acquisition systems, digital signal processing and system identification. Test facilities constitute a key factor for improving the quality of the estimated modal model. This paper aims to describe the experimental facilities at the Institute of Aeronautics and Space (IAE) Modal Testing Laboratory in terms of associated instrumentation and data acquisition system, metrological aspects and computational resources. The discussion is completed with a practical application showing a ground vibration testing (GVT) of an unmanned aerial vehicle (UAV).

The experimental facilities were evaluated in a typical GVT, using three shakers in both vertical and horizontal excitations and 88 response measurement points. The global excitation method was used to excite all desired modes. The reliability of the experimental modal model was validated by an auto modal assurance criterion matrix for the measured modes of the structure.

The experimental facilities were successfully used for validating the dynamical characteristics of the UAV under testing.

The modal test facilities of the Modal Testing Laboratory at the IAE, the main research center of the Brazilian Air Force, are described in this paper.

This paper describes a free‐piston driven expansion tube and its instrumentation. The facility is used to generate rarefied flows at speeds of approximately 10 km/s. Although the flow in the tube itself is in the continuum regime, rarefied flow conditions are achieved by allowing the test gas to further expand as a free jet into the facility's test section. The test flow is surveyed to provide bar‐gauge pressure measurements. Numerical simulation is then used to describe more fully the test flow properties. The flows produced are suitable for the aerodynamic testing of small models at superorbital speeds and should provide data that are suitable for the calibration of Direct Simulation Monte‐Carlo codes.

Prior studies identified a need for further comparison of data-sharing practices across different disciplines and communities. Toward addressing this need, the purpose of this paper is to examine the data-sharing practices of the earthquake engineering (EE) community, which could help inform data-sharing policies in EE and provide different stakeholders of the EE community with suggestions regarding data management and curation.

This study conducted qualitative semi-structured interviews with 16 EE researchers to gain an understanding of which data might be shared, with whom, under what conditions and why; and their perceptions of data ownership.

This study identified 29 data-sharing factors categorized into five groups. Requirements from funding agencies and academic genealogy were frequent impacts on EE researchers’ data-sharing practices. EE researchers were uncertain of data ownership and their perceptions varied.

Based on the findings, this study provides funding agencies, research institutions, data repositories and other stakeholders of the EE community with suggestions, such as allowing researchers to adjust the timeframe they can withhold data based on project size and the amount of experimental data generated; expanding the types and states of data required to share; defining data ownership in grant requirements; integrating data sharing and curation into curriculum; and collaborating with library and information schools for curriculum development.

Construction work is due to start next month on Hanker Siddeley's first export Jason, ordered by the Dutch Reactor Centre near Amsterdam

The purpose of this study is to evaluate the effect of tabs having different corner geometries on the flow characteristics of a supersonic convergent–divergent (C-D) nozzle.

A circular C-D nozzle of Mach 2.0 was used, and the tabs were positioned at the exit of the nozzle in diametrically opposite directions. Three tabs having different corner geometry implemented in the experiments were rectangular tab with triangular top edge, triangular tab with a bell-shaped edge and tapered tab. The pressure profiles across the tabs and the centerline pressure decay along the jets were measured. The shadowgraph technique illustrated the waves present in the center of an oncoming jet. The nozzle pressure ratios (NPR) were varied from 4 to 8, in the steps of one, covering various overexpansion and under expansion levels at the exit of the nozzle.

The results showed tapered tabs act as a better mixing promoter than the other tabs used in the study. A reduction of 91.25% in core length for NPR 8 was observed for the tapered tabs. Subsequently, core length reductions generated by triangular tabs with a bell-shaped top edge were 87.5%, and those caused by rectangular tabs with a triangular top edge were 7.5%.

The research results could be used for designing combustion chambers and chemical reactors that require jets to enhance mixing levels.

The tabs having three different corners geometries, i.e. sharp or pointed, bell-shaped and straight edge has never been investigated before. The idea of only modifying corners is the innovative step of this research.

The purpose of this paper is to develop multi-physics computational model for the conventional gas metal arc welding (GMAW) joining process has been improved with respect to its predictive capabilities regarding the spatial distribution of the mechanical properties (strength, in particular) within the weld.

The improved GMAW process model is next applied to the case of butt-welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using filler-metal electrodes made of the same material. A critical assessment is conducted of the basic foundation of the model, including its five modules, each dedicated to handling a specific aspect of the GMAW process, i.e.: first, electro-dynamics of the welding-gun; second, radiation/convection controlled heat transfer from the electric arc to the workpiece and mass transfer from the filler-metal consumable electrode to the weld; third, prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; fourth, the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; and fifth, spatial distribution of the as-welded material mechanical properties.

The predictions of the improved GMAW process model pertaining to the spatial distribution of the material microstructure and properties within the MIL A46100 butt-weld are found to be consistent with general expectations and prior observations.

To explain microstructure/property relationships within different portions of the weld, advanced physical-metallurgy concepts and principles are identified, and their governing equations parameterized and applied within a post-processing data-reduction procedure.

The purpose of this research is to identify how the management of university institutes can be improved through adoption of an integrated performance measurement system based on the Balanced Scorecard.

Through building on literature studies and management best practice, formulation of the performance measurement system was explored. The Balanced Scorecard solution was then designed and implemented at a university institute. Benefits and outcomes are discussed through reflective analysis of the case study investigation.

The study identified how the development of scorecard reports that include economic and non‐economic measures can improve the operational management of a university institute through providing tangible benefits to stakeholders.

The scorecard was investigated at an industry‐supported university institute and so features of the scorecard design and implementation may be less relevant to other types of organisations.

This research paper provides details on how the scorecard has been modified to provide an accessible and durable measurement system. The paper includes specific guidance for practitioners who are considering implementing the scorecard.

The role of intellectual capital and soft measures as systemic determinants of performance is discussed and this is viewed in terms of university‐industry collaborations.

A comprehensive literature review underpins a two‐year research project involving strategy mapping, design and implementation of the Balanced Scorecard. Advice on modification of the scorecard and provision of representative data and information from reports serve to further the scorecard research agenda.

The purpose of this study is to explore the influence of an office canteen layout on operations, specifically on customer behaviour before checkout, waiting times, and congestion.

The current study was made in the context of discovery and exemplification. The sample was not randomly obtained: the method of recruitment was purposive and convenient. Two Dutch office canteens were selected based on their motivation to participate in the study. A small exploratory study aiming to report on current practices and to inform on possibilities for future research and intervention. With direct observations the behaviour, waiting times, and congestion of 47 customers were analyzed. Customer behaviour was reported qualitatively, waiting times and congestion were reported quantitatively.

Canteens where customers can move freely before checkout queue, allow them to move away from congestion towards food products and to have more favourable waiting times than customers in canteens with layouts requiring a strict order and line‐up for self‐service and checkout.

The results contribute to the managerial repertoire of facilities managers by illuminating latent positive influences of facility layout on operations, which can stimulate the design of better facilities.

This paper contributes to the understanding of how facilities are interwoven with operations. It also informs on possibilities for future research in this area, for instance, combining approaches that originate from facilities management and operations management. This may lead to future research to recommend specific designs or behaviour‐inducing layouts for increased operational enhancements.

This paper's aim is to determine whether shopping facilities in a waiting area influence customer behaviour and whether these behaviours positively influence their satisfaction and related sales of the displayed products.

The approach used was a field experiment. At two sites patient behaviours were directly observed before a reconstruction of waiting areas during two weeks; at both sites a two‐week follow‐up was performed after the reconstruction. The responses of patients were surveyed in a convenience sample in the same periods of weeks and the data on sales were collected with desk research.

In comparison with waiting areas that were almost empty, customers in a waiting area with shopping facilities had more interaction with the physical environment, experienced a shorter wait, were more satisfied with the prompt taking of orders, and spent more money.

Organizations seeking to positively influence patient behaviour during the wait should take into account the quality of facility design of waiting areas and, if well chosen, these facilities can also be used to positively influence satisfaction and sales.

This paper integrates theories from environmental psychology, marketing, and operations management in facility design to improve the properties of a waiting area, and by doing so, improve behaviour, satisfaction, and sales of customers. The study aims to inform marketers in the pharmacy shop sector allowing them to increase interaction with the shopping environment, improve customers' satisfaction, and raise customers' expenditures with facilities.

The purpose of this paper is to consider queuing systems where captive repeat customers select a service facility each period. Are people in such a distributed system, with limited information diffusion, able to approach optimal system performance? How are queues formed? How do people decide which queue to join based on past experience? The authors explore these questions, investigating the effect of information availability, as well as the effect of heterogeneous facility sizes, at the macro (system) and micro (individual performance) levels.

Experimental economics, using a queuing experiment.

The authors find little behavioural difference at the aggregate level, but observe significant variations at the individual level. This leads the authors to the conclusion that it is not sufficient to evaluate system performance by observing average customer allocation and sojourn times at the different facilities; one also needs to consider the individuals’ performance to understand how well the chosen design works. The authors also observe that better information diffusion does not necessarily improve system performance.

Evaluating system performance based on aggregate behaviour can be misleading; however, this is how many systems are evaluated in practice, when only aggregate performance measures are available. This can lead to suboptimal system designs.

There has been little theoretical or empirical work on queuing systems with captive repeat customers. This study contributes to the understanding of decision making in such systems, using laboratory experiments based on the cellular automata approach, but with all agents replaced by humans.