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Based on the aerodynamic loads and dynamic performances of trains, this study aims to investigate the effect of crosswinds and raindrops on intercity trains operating on viaducts to ensure the safe operation of intercity railways in metropolitan areas.

An approach coupled with the Euler multiphase model as well as the standard k-ɛ turbulence model is used to investigate the coupled flow feature surrounding trains and viaducts, including airflow and raindrops, and the numerical results are validated with those of the wind tunnel test. Additionally, the train’s dynamic response and the operating safety region in different crosswind speeds and rainfall is investigated based on train’s aerodynamic loads and the train wheel–rail dynamics simulation.

The aerodynamic loads of trains at varying running speeds exhibit an increasing trend as the increase of wind speed and rainfall intensity. The motion of raindrop particles demonstrates a significant similarity with the airflow in wind and rain environments, as a result of the dominance of airflow and the supplementary impacts of droplets. As the train’s operating speed ranged between 120 and 200 km/h and within a rainfall range of 20–100 mm/h, the safe operating region of trains decreased by 0.56%–7.03%, compared with the no-rain condition (0 mm/h).

The impact of crosswind speeds and rainfall on the train’s aerodynamic safety is studied, including the flow feature of crosswind and different particle-sized raindrops around the train and viaduct, aerodynamic loads coefficients suffered by the intercity train as well as the operating safety region of intercity trains on the viaduct.

In this paper, an approximate analytical approach is developed for the determination of natural longitudinal frequencies of a cantilever-cracked beam based on the Lagrange inversion theorem.

The crack is modeled by an equivalent axial spring with stiffness according to Castigliano's theorem. Thus, an implicit frequency equation corresponding to cantilever-cracked bar is obtained. The resulting equation is solved using the Lagrange inversion theorem.

Effect of different crack depths and crack positions on natural frequencies of the cracked beam is analyzed. It is shown that an increase in the crack depth ratio produces a decrease in the fundamental longitudinal natural frequency of a cracked bar. Furthermore, approximate analytical results are compared with those obtained numerically as well as from experimental tests.

A new approximate analytical expression of a fundamental longitudinal frequency, as a function of crack depth and crack location, is obtained.

The purpose of this paper is to introduce a new numerical approach for studying a cantilever bar having a transverse crack. The crack is modeled by an elastic longitudinal spring with a stiffness K according to Castiglione’s theorem.

The bar is excited by different longitudinal impulse forces. The considered problem based on the differential equation of motion is solved by the method of characteristics (MOC) after splitting the second-order motion equation into two first-order equivalent equations.

In this study, effects of the crack size and crack’s position on the reflected waves from the crack are investigated. The results indicate that the presence of the crack in the cantilever bar generates additional waves caused by the reflection of the incident wave by the crack.

A numerical approach developed in this paper is used for detecting the extent of the damage in cracked bars by the measurement of the difference between the dynamic response of an uncracked bar and a cracked bar.

Polymeric coatings and packaging are often used to enhance the temperature sensitivity of fiber Bragg grating temperature sensors. The high thermal expansion coefficient of the polymer enhances the thermal sensitivity by improving the wavelength shift due to thermal expansion. The adhesion of the polymeric coatings to the silica based optical fiber plays an important role in the wavelength response characteristics of fiber Bragg gratings with respect to temperature. Experiments are done to qualitatively analyze the influence of adhesion. Three‐dimensional finite element simulations have been carried out. Spring elements are used to interconnect the nodes of the meshed models of optical fiber and coating. The effect of adhesion is studied as a function of spring stiffness.

IT is sale to say that in no branch of applied science have the difficulties been greater or the process of development more rapid than in aeronautics. By far the largest factor in the triumph of the aeroplane has been the improved internal combustion engine, a class of prime mover which, generating a maximum of power for a minimum of weight from concentrated fuel, is to‐day such an outstanding engineering achievement as to arouse one's curiosity regarding its origin and development.

This paper aims to carry out assembly variation analysis for mechanisms with compliant joints by considering deformations induced by manufactured deviations. Such an analysis procedure extends the application area of direct linearization method (DLM) to compliant mechanisms and also illustrates the dimensional interaction within multi-loop compliant structures.

By applying DLM to both geometrical equations and Lagrange’s equations of the second kind, an analytical deviation modeling method for mechanisms with compliant joints are proposed and further used for statistical assembly variation analysis. The precision of this method is verified by comparing it with finite element simulation and traditional DLM.

A new modeling method is proposed to represent kinematic relationships between joint deformations and parts/components deviations. Based on a case evaluation, the computational efficiency is improved greatly while the modeling accuracy is maintained at more than 94% rate comparing with the benchmark finite element simulation.

The Equilibrium Equations of Incremental Forces derived from Lagrange’s equations are proposed to quantitatively represent the relationships between manufactured deviations and assembly deformations. The present method extends the application area of DLM to compliant structures, such as automobile suspension systems and some Micro-Electro-Mechanical-Systems.

While there has been increasing interest in the impact of courtmandated education finance reform on school district efficiency, research on the subject is scant. Taking advantage of New Jersey Supreme Court cases that have altered the way in which state school aid is distributed, this paper examines the effect of changes in the education finance system on school district efficiency. Building on existing literature on public sector efficiency, a longitudinal data analysis based on two-stage DEA models reveals that courtmandated increases in state aid to a limited number of poor school districts decreased the districts' efficiency. Though these results should be interpreted with some caution, in particular, the limitation of DEA as an efficiency measure, they imply that, as with any policy, policy makers and courts should be aware of how policy changes affect local government behavior and that it is necessary to evaluate policy outcome taking into account both resources and performance.

The purpose of this paper is to address the determination of crack location and depth of multiple transverse cracks by monitoring natural frequency and its prediction using Artificial Neural Networks (ANN). An alternative to the existing NDTs is suggested.

Modal analysis is performed to extract the natural frequency. Analysis is performed for two cases of cracks. In first case, both cracks are perpendicular to axis. In second case, both cracks are inclined to vertical plane and also inclined with each other. Finite element method (FEM) is performed using ANSYSTM software which is theoretical basis. Experimentation is performed using Fast Fourier Transform (FFT) analyzer on simply supported stepped rotor shaft and cantilever circular beam with two cracks each.

The results of FEM and experimentation are validated and are in good agreement. The error in crack detection by FEM is in the range of 3-15 percent while 5-20 percent by experimentation. The database obtained by modal analysis is used to train the network of ANN which predicts crack characteristics. Validity of method is investigated by comparing the predictions of ANN with FEM and experimentation. The results are in good agreement with error of 7-16 percent between ANN and FEM while 9-21 percent between ANN and experimental analysis.

It envisages that the method is capable. It is an effective as well as an alternate method of fault detection in beam/rotating element to the existing methods.

The Beyond Budgeting movement has argued that traditional budgets failed to contribute to the management of tensions associated with the increasing complexity of business models. The literature has reported a range of budgeting practices developed to address these problems, which the authors refer to collectively as “non-traditional (NT) budgets.” The purpose of this paper is to consider how the design and use of a NT budgeting system facilitates the management of multiple organizational tensions.

The study reports the findings of an in-depth case study on three business units (BUs) of the French chemical giant SSB, a company that implemented a NT budget inspired by the Beyond Budgeting Round Table model.

The authors provide detailed empirical insights into the design and use of a NT budgeting system and analyze the manner in which the new system exposes organizational tensions across multiple axes.

It is a limitation of the study that only three of SSB 21 BU’s which implemented the NT budget project were examined in depth. This limitation is mitigated to some extent by the review of audit reports in respect of the implementation of the NT budget in a total of 15 BU’s.

The study contributes a means of analyzing NT budgets in terms of the different types of organizational tensions generated, which should be of use to both researchers and practitioners in researching, designing, and evaluating NT budgets.

This study provides detailed empirical insights into the design and use of a NT budgeting system and evidence of the success of this system in exposing organizational tensions across multiple axes. The study illustrates how productive tensions can be generated through the analysis of discrepancies between alternative views of organizational performance.

Purpose – Studies suggest that children's experiences during first grade help establish educational trajectories that eventually shape their life chances. Research also indicates that student attentiveness in the classroom is integral to learning and later academic achievement, with low-income students of color running a greater risk of “attentional difficulties.”

Methodology – Joining these two bodies of work, I map the social conditions that shape attentiveness in the first-grade classrooms of “at-risk” students. Using ethnographic data collected over three school years, I examine how children actively construct attentiveness during their everyday interactions at school.

Findings – First graders sustain attention but often onto their own auto-involvements and mutual engagements, focal concerns teachers consider “distractions.” By learning the moment-by-moment variations of what to pay attention to and how “attentiveness” looks, children navigate the social ropes of schooling. Young students apply these lessons to self and peers, regulating attentiveness and socializing one another to the norms of their classroom. They are also resourceful actors who skillfully use their understandings of attentiveness to maneuver around the strict order of the day. Schoolchildren multitask, conceal other focal concerns, and give the impression of attentiveness, all of which influence what behaviors get detected as “(in)attentive.”