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The application of reduced order models (ROMs) in the aerodynamic/aeroelastic analysis of long-span bridges, unlike the aeronautical structures, has not been extensively studied. ROMs are computationally efficient techniques, which have been widely used for predicting unsteady aerodynamic response of airfoils and wings. This paper aims to discuss the application of a reduced order computational fluid dynamics (CFD) model based on the eigensystem realization algorithm (ERA) in the aeroelastic analysis of the Great Belt Bridge (GBB).

The aerodynamic impulse response of the GBB section is used to construct the aerodynamic ROM, and then the aerodynamic ROM is coupled with the reduced DOF model of the system to construct the aeroelastic ROM. Aerodynamic coefficients and flutter derivatives are evaluated and compared to those of the advanced discrete vortex method-based CFD code.

Results demonstrate reasonable prediction power and high computational efficiency of the technique that can serve for preliminary aeroelastic analysis and design of long-span bridges, optimization and control purposes.

The application of a system identification tool like ERA into the aeroelastic analysis of long-span bridges is performed for the first time in this work. Authors have developed their earlier work on the aerodynamic analysis of long-span bridges, published in the Journal of Bridge Engineering, by coupling the aerodynamic forces with reduced DOF of structural system. The high computational efficiency of the technique enables bridge designers to perform preliminary aeroelastic analysis of long-span bridges in less than a minute.

This paper aims to provide the results of investigations concerning an influence of the tyre with longitudinal grooves on the car body aerodynamics. It is considered as an important aspect affecting the vehicle aerodynamic drag.

To investigate a contribution of grooved tyres to the overall vehicle drag, three wind tunnel experimental campaigns were performed (two by Peugeot Société Anonyme Peugeot Citroen, one at the Lodz University of Technology). In parallel, computational fluid dynamics (CFD) simulations were conducted with the ANSYS CFX software to enable formulation of wider conclusions.

The research shows that optimised tread patterns can be derived on a single tyre via a CFD study in combination with a controlled experiment to deliver designs actively lowering the overall vehicle aerodynamic drag.

A reduction in the aerodynamic drag is one of ways to decrease vehicle fuel consumption. Alternatively, it can be translated into an increase in the maximum travel velocity and the maximum distance driven (key factor in electric vehicles), as well as in a reduction of CO₂ emissions. Finally, it can improve the vehicle driving and steering stability.

The tyre tread pattern analysis on isolated wheels provides an opportunity to cut costs of R&D and could be a step towards isolating aerodynamic properties of tyres, irrespective of the car body on which they are applied.

Addresses the question of how well the banking industry in Australia understands the needs of their business customers. It is based on a nationwide survey of chief executive officers of 2,500 business firms and 25 banks conducted during 1996. In the survey, both groups were asked to rank those factors they consider most important in the bank selection process. Overall, significant differences were found in six out of 15 factors. When the responses were analyzed on the basis of market segment served, we found that Australian bankers have missed the mark when it comes to the issues of competitive prices and service delivery. These results will no doubt have an impact on the marketing efforts of Australian banks as they move into the twentieth century. They should also be useful to firms currently operating in Australia or firms interested in doing so in the future.

In this study, a finite element model of a box-girder bridge along with the railway sub-track system is developed to predict the static behavior due to different combinations of the Indian railway system and free vibration responses resulting in different natural frequencies and their corresponding mode shapes.

The modeling and evaluation of the bridge and sub-track system were performed using non-closed form finite element method (FEM)-based ANSYS software.

From the analysis, the worst possible cases of deformation and stress due to different static load combinations were determined in the static analysis, while different natural frequencies were determined in the free vibrational analysis that can be used for further analysis because of the dynamic effect of the train vehicle.

The scope of the current investigation is confined to the structure's static and free vibration analysis. However, this study will help the designers obtain relevant information for further analysis of the dynamic behavior of the bridge model.

In static analysis, the maximum deformation of the bridge deck was found to be 10.70E-03m due to load combination 5, whereas the maximum natural frequency for free vibration analysis is found to be 4.7626 Hz.

The purpose of this article is to contribute to an understanding of how diverse groups of employees perceive their workplaces as learning environments, and to cast light on the learning processes of these diverse groups of employees.

This study was designed to examine employee perceptions of: the extent to which their managers create conditions in the work environments favourable to learning and enact behaviours in one‐on‐one settings that are likely to foster learning; and their sources and methods of learning. Data were gathered from 464 employees in 31 small manufacturing firms through self‐completion questionnaires and analysed using descriptive statistics and t‐tests.

Results for six demographic groups are presented to provide a comparative view of employee perceptions. The research found that the two comparison groups within three demographic variables (tenure, age, education) differed markedly in how they perceived their workplaces as learning environments. However, the various comparison groups seemed to agree that workmates and observational processes were central to learning.

The research reveals demographic variables that appear to be important in studies of employee learning in small firms. These variables are: tenure, education, and age. Future research should examine owner‐managers' perceptions of the workplace learning environments and employee learning processes.

Managers may need practical help in managing the learning of diverse groups of employees, and in understanding the potential differences in employee learning processes.

Departs from small business research practice by providing an employee perspective and examining informal learning processes, as opposed to training practices.

This study is a pioneer in the academic literature to investigate the relationship between Valentine’s Day and stock market returns of major economies around the world.

Specific control variables for Valentine's Day are introduced to eliminate the potential influence of other effects.

The findings indicate that stock returns are higher on the days when Valentine's Day is approaching than on other days for most cases, showing “the Valentine Effect” in the stock market.

Unlike other holiday effects in the previous literature, the Valentine's Day effect cannot be explained by many conventional theories, such as tax-loss selling and the inventory adjustment hypothesis.

Diffusion patterning is a dielectric patterning technology, which is used in the screen printed thick film technology for higher density multilayer circuits. This technology is suitable for producing lower cost multichip modules and requires a low additional investment in conventional thick film technology production lines. Comparisons of via resolution capability of diffusion patterning versus conventional thick film technology are described and discussed. Preliminary experimental results obtained with a test circuit showed that 200μm lines and 200μm vias could be achieved with acceptable yield and with minimal modification to standard production lines. The electronic circuit for the pressure sensor was designed and realised with the verified technology as a low‐cost ceramic multichip module. A few results of an investigation of some thick film materials, which comprise the “set” of pastes for diffusion patterning technology, are presented.

There appears to be no empirical-based method in the literature for estimating if an engineering change proposal (ECP) will occur or the dollar amount incurred. This paper aims to present an empirically based approach to address this shortfall.

Using the cost assessment data enterprise database, 533 contracts were randomly selected via a stratified sampling plan to build two regression models: one to predict the likelihood of a contract experiencing an ECP and the other to determine the expected median per cent increase in baseline contract cost if an ECP was likely. Both models adopted a stepwise approach. A validation set was placed aside prior to any model building.

Not every contract incurs an ECP; approximately 80 per cent of the contracts in the database did not have an ECP. The likelihood of an ECP and the additional amount incurred appears to be statistically independent of acquisition phase, branch of service, commodity, contract type or any other factor except for the basic contract amount and the number of contract line item numbers; both of these later variables equally affected the contract percentage increase because of an ECP. The combined model overall bested current anecdotal approaches to ECP withhold.

This paper both serves as a published reference point for ECP withholds in the archival forum and presents an empirically based method for determining per cent ECP withhold to use.

Organizational agility may be considered the integration of organizational processes, characteristics, and members with advanced technology. Agility enhances the organization’s ability to provide high quality products and services and is, therefore, crucial to organizational competitiveness. Integrates the production/operations, general management, and sociotechnical views to develop a model of organizational agility. Briefly reviews the literature in these fields and offers a model of agility based on suppliers, organizational members, and customers united through information technology. It is proposed that these connections rest on a foundation of leadership, organization culture, and employee reward systems that create a relationship between people and technology. These relationships include involving people in decision making, creating process and product quality by offering enriched jobs, training in technology, and providing a reward system which reinforces agility‐promoting efforts.

This paper presents an alternative approach to evaluating the overall efficiency and performance of Taiwanese container ports. Specifically, a parallel activity with series structure concept in the form of data envelopment analysis (MNDEA) is used to construct a model that applies to three different activities: harbor management, stevedoring and warehousing operations. We will further divide each activity into two process types, production processes and services processes. We will also adopt a Delphi survey approach and use the Analytic Network Process (ANP) to identify these processes’influence dependence and their degree of importance for the MNDEA model setting. An empirical application demonstrates the performance of Taiwanese container ports by using MNDEA with window analysis techniques via the directional distance functionThe results demonstrate that the application is effective in indicating and/or suggesting resource-adjustments, while considering which undesirable output levels and shared inputs were involved. The results also present directions for possible improvements in workplace efficiency.