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This paper investigates whether an outcome-based school aid formula could improve fiscal and outcome equity significantly more than a typical aid formula would. When…
Abstract
This paper investigates whether an outcome-based school aid formula could improve fiscal and outcome equity significantly more than a typical aid formula would. When outcome-based formula is applied to foundation aid, fiscal and outcome equity deteriorates compared to Ohio's recent aid formula. However, when it is applied to power-equalizing aid, the latter improves fiscal and outcome equity more significantly than both foundation aid and Ohio's recent aid formula do. This paper further shows how to apply them to real-world cases. The lessons from this paper can be easily applied to similar grant systems with standardized test scores.
Marilyn Fernandez and Laura Nichols
Proclaims that in recent years there has been considerable research examining the benefits of social connectedness for a variety of outcomes, such as health and general…
Abstract
Proclaims that in recent years there has been considerable research examining the benefits of social connectedness for a variety of outcomes, such as health and general well being. Argues, while bonding capital is beneficial to the self‐interest of the individual or small group, bridging capital is what is necessary to build a collective identity as a nation. Concludes that because people have varying access, with regard to formal organizations, their ability to use social capital for their benefit, and the benefit of their communities, may be of short‐term duration.
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Wessie W.S. Ling, Gail Taylor and M.T. Lo
Bridge lines represent a way for designers to expand their business, because typically designer merchandise is supplied to a limited number of stores. With bridge lines…
Abstract
Bridge lines represent a way for designers to expand their business, because typically designer merchandise is supplied to a limited number of stores. With bridge lines, the prices are lower and the line can be supplied to more stores. The bridge line market has been rapidly evolving in recent years. Retailers are paying close attention to this sector, particularly in the light of the stagnant demand for more expensive designer ready‐to‐wear collections. Despite the general economic recession, the culture of wearing fashion in the 1990s has paved the way to the growth of bridge lines.
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Robert C. Guyer and Jeffrey A. Laman
Limited funding to maintain and preserve short‐line railroad (SLRR) bridge infrastructure requires that important priority decisions be made on an annual basis. The…
Abstract
Purpose
Limited funding to maintain and preserve short‐line railroad (SLRR) bridge infrastructure requires that important priority decisions be made on an annual basis. The compartmentalized, dispersed, and diverse nature of many SLRR owners and operators is such that there is a need for a coordinated and centralized effort to evaluate the state‐wide system as a whole, to ensure the most effective overall resource allocation and also identify assets that either outperform predictions or consume disproportionate levels of resources for maintenance and operation, allowing for review of design and construction practices. The purpose of this paper is to examine the state of the art for railroad bridge population management and resource allocation decisions and to develop a state‐wide SLRR bridge prioritization methodology, to be used as a tool by a state agency to assist in allocating limited public funding for bridge maintenance, rehabilitation and replacement activities.
Design/methodology/approach
A literature review examining the state of the art of railroad bridge population management and resource allocation decisions was conducted, which provided the foundation for the development of a bridge prioritization algorithm. A state‐wide survey was conducted to develop a bridge database. A detailed evaluation of a statistically significant sample of bridges was conducted, to determine the structural and maintenance needs and preservation status of sub‐populations. The research team developed methodologies, applicable to the entire population, to develop a ranking of bridge preservation candidates.
Findings
A risk‐based prioritization algorithm is proposed to assign a relative risk score to each bridge in the population. The algorithm provides a management tool for making more effective maintenance and preservation decisions. Additionally, the bridge database allows managers to examine sub‐populations according to structural parameters to evaluate performance.
Originality/value
The revisable, modular framework of the prioritization algorithm provides a simple, effective and versatile tool for asset management and evaluation. The present proposal of this new prioritization methodology for SLRR bridges is a valuable tool for agencies faced with making rational decisions with limited information. Such a methodology does not currently exist in the literature and is of significant interest to short‐line owners/operators and state transportation agencies.
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Mohammad Hadi Hafezi, N. Nik Abdullah, José F.O. Correia and Abílio M.P. De Jesus
Fatigue crack growth models based on elastic‐plastic stress‐strain histories at the crack tip region and strain‐life damage models have been proposed. The UniGrow model…
Abstract
Purpose
Fatigue crack growth models based on elastic‐plastic stress‐strain histories at the crack tip region and strain‐life damage models have been proposed. The UniGrow model fits this particular class of fatigue crack propagation models. The residual stresses developed at the crack tip play a central role in these models, since they are applied to assess the actual crack driving force. This paper aims to assess the performance of the UniGrow model based on available experimental constant amplitude crack propagation data, derived for several metallic materials from representative Portuguese bridges. It also aims to discuss key issues in fatigue crack growth prediction, using the UniGrow model, in particular the residual stress computation and the suitability of fatigue damage rules.
Design/methodology/approach
The UniGrow model is assessed using data derived by the authors for materials from Portuguese riveted metallic bridges. Strain‐life data, from fatigue tests on smooth specimens, are used to propose a convenient fatigue damage model. Predicted crack growth rates are compared with experimental crack propagation data obtained by authors using fatigue tests on compact tension specimens. Since the UniGrow model is a residual stress‐based propagation model, elastoplastic finite element analysis is proposed for comparison with the analytical approach implemented in the original UniGrow model.
Findings
The use of the Smith‐Watson‐Topper damage parameter overestimates the stress R‐ratio effects on crack propagation rates, mainly if the material shows crack propagation rates with small to moderate sensitivity to stress R‐ratio, which is the case of the materials under investigation in this paper. Alternatively, the application of the Coffin‐Manson damage law leads to consistent fatigue crack growth predictions for the investigated range of positive stress R‐ratios. The stress R‐ratios effects may be solely attributed to the residual stresses. Their estimation, using an analytical approach, may lead to inconsistent results, which is demonstrated by an alternative elastoplastic finite element analysis.
Originality/value
Contributions for more accurate predictions of fatigue crack propagation rates, for several stress ratios, using a strain‐based approach is proposed. This approach is valuable since it may be used to reduce the time consuming and costly fatigue crack propagation tests. Furthermore, the proposed approach shows potential for an unified crack initiation and propagation approach.
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Yuji Sugitani, Yoshihiro Kanjo and Masatoshi Murayama
Describes the use of welding robots for making bridge panels. The systemuses a total of 14 sets of High Speed Rotating Arc welding robots andnewly‐developed arc sensor…
Abstract
Describes the use of welding robots for making bridge panels. The system uses a total of 14 sets of High Speed Rotating Arc welding robots and newly‐developed arc sensor techniques are used with both joint end and bead end sensors. A teaching‐less direct CADCAM system was developed to control the robots. The welding robot system is now in commercial operation with welding efficiencies that are twice those possible with conventional processes.
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Ming-Yi Liu, Li-Chin Lin and Pao-Hsii Wang
The purpose of this paper is to provide a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of…
Abstract
Purpose
The purpose of this paper is to provide a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure.
Design/methodology/approach
Based on the smooth and convergent bridge shapes obtained by the initial shape analysis, the one-element cable system (OECS) and multi-element cable system (MECS) models of the symmetric harp cable-stayed bridge are developed to verify the applicability of the analytical model and numerical formulation from the field observations in the authors’ previous work. For this purpose, the modal analyses of the two finite element models are conducted to calculate the natural frequency and normalized mode shape of the individual modes of the bridge. The modal coupling assessment is also performed to obtain the generalized mass ratios among the structural components for each mode of the bridge.
Findings
The findings indicate that the coupled modes are attributed to the frequency loci veering and mode localization when the “pure” deck-tower frequency and the “pure” stay cable frequency approach one another, implying that the mode shapes of such coupled modes are simply different from those of the deck-tower system or stay cables alone. The distribution of the generalized mass ratios between the deck-tower system and stay cables are useful indices for quantitatively assessing the degree of coupling for each mode. For each identical group of stay cables in the MECS model, the local modes with similar natural frequencies and normalized mode shapes consist of the participation of one or more stay cables. These results are demonstrated to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges.
Originality/value
It is important to investigate the deck-stay interaction with the appropriate initial shape of a cable-stayed bridge. This is because such initial shape not only reasonably provides the geometric configuration as well as the prestress distribution of the bridge under the weight of the deck-tower system and the pretension forces in the stay cables, but also definitely ensures the satisfaction of the relations for the equilibrium conditions, boundary conditions and architectural design requirements. However, few researchers have studied the deck-stay interaction considering the initial shape effect. The objective of this paper is to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure. The modal coupling assessment is also performed for quantitatively assessing the degree of coupling for each mode of the bridge.
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Roger V. Patulny and Gunnar Lind Haase Svendsen
The purpose of this paper is to show that numerous studies have advanced social capital research over the past decade. Most studies have accepted the theoretical…
Abstract
Purpose
The purpose of this paper is to show that numerous studies have advanced social capital research over the past decade. Most studies have accepted the theoretical distinction between bonding and bridging social capital networks. Many, however, tend to agglomerate empirical research under the one catch‐all social capital concept, rather than classifying it according to the bonding/bridging distinction. Furthermore, most studies make little distinction on the basis of methodology, between qualitative and quantitative approaches to investigating social capital. These omissions need to be addressed.
Design/methodology/approach
This paper reviews definitions and applications of bridging and bonding social capital, classifies empirical studies according to each network type, and produces a further breakdown according to methodological approach.
Findings
The result is a four‐part “grid” of social capital research, encompassing bonding and bridging, and quantitative and qualitative aspects. This paper finds that most qualitative research examines non‐excludable and excludable goods and is relevant to bonding social capital, whilst most quantitative analysis looks at civic networks and norms of trust, and relates to bridging social capital.
Research limitations/implications
Results advance the task of clarifying and measuring social capital.
Practical implications
Further development of the bridging/bonding social capital conceptual pair should allow for a more precise measurement of a community, or region.
Originality/value
No review paper to date captures the above empirical and methodological “grid” clearly.
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Kazuaki Miyamoto, Surya Raj Acharya, Mohammed Abdul Aziz, Jean-Michel Cusset, Tien Fang Fwa, Haluk Gerçek, Ali S. Huzayyin, Bruce James, Hirokazu Kato, Hanh Dam Le, Sungwon Lee, Francisco J. Martinez, Dominique Mignot, Kazuaki Miyamoto, Janos Monigl, Antonio N. Musso, Fumihiko Nakamura, Jean-Pierre Nicolas, Omar Osman, Antonio Páez, Rodrigo Quijada, Wolfgang Schade, Yordphol Tanaboriboon, Micheal A. P. Taylor, Karl N. Vergel, Zhongzhen Yang and Rocco Zito