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Article
Publication date: 14 June 2011

Lijie Ding, Yijia Cao, Guangzeng Wang and Meijun Liu

The purpose of this paper is to study the failures spread in complex power grids, and what topology of power grids is best for preventing or reducing blackouts.

Abstract

Purpose

The purpose of this paper is to study the failures spread in complex power grids, and what topology of power grids is best for preventing or reducing blackouts.

Design/methodology/approach

Based on the study of cascading failure models of complex power networks, an extended dynamical cascading failure model is proposed. Based on this model, two representatives of the complex power grids, the small‐world network and the scale‐free network, were simulated for line cascading failure. The power loss caused by cascading failures and the spreading speed of cascading failure are discussed.

Findings

Power loss caused by cascading failures in the small‐world network is much larger than that in the scale‐free network, and the speed of cascading failure propagation in the small‐world network is much faster than that in the scale‐free network.

Research limitations/implications

The establishment of the dynamical cascading failure model considering other protection devices needs further study.

Practical implications

The results of this study can be beneficial in system planning and upgrading.

Originality/value

An extended dynamical cascading failure model is proposed and cascading failures in different topology of power grid are discussed.

Details

Kybernetes, vol. 40 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 January 2005

H. Yao, J. Butterfield, S. Raghunathan, Jian Wang, R. Cooper and E. Benard

reverser considered in this paper uses the natural blockage concept, with only the fan duct flow being reversed. This paper focuses on the study of the aerodynamic performance of…

Abstract

reverser considered in this paper uses the natural blockage concept, with only the fan duct flow being reversed. This paper focuses on the study of the aerodynamic performance of the cascade within a cold stream thrust reverser. Aerodynamic simulations are carried out using realistic operating conditions, for idealized cascade models representing three design options. The aim of this work is to investigate whether the aerodynamic performance of the thrust reverser cascade has been improved while minimizing weight of the cascade. In addition, t1his is the first attempt of us to considering noise reduction during design of the thrust reverse. The numerical simulations show that despite a reduction in total reverse thrust for the weight reduced designs, the supersonic flow regime, which existed in the original design, was eliminated after changing vane configurations made with the 5% and 10% weight reductions. The aerodynamic performance around the cascade and in the fan duct within the thrust reverser has been improved. Moreover, the acoustic characteristics of the thrust reverser are improved too. The total reverse thrust is not significantly affected with the modified cascade.

Details

Multidiscipline Modeling in Materials and Structures, vol. 1 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Book part
Publication date: 7 June 2010

K.W.G. Rekha Nianthi and M.A.S. Jayakumara

Sri Lanka, as an island located near the southern tip of India and the Asian Continent and in the core area of the South Asian Monsoon has developed its own unique forms of…

Abstract

Sri Lanka, as an island located near the southern tip of India and the Asian Continent and in the core area of the South Asian Monsoon has developed its own unique forms of Hydraulic Civilization. Sri Lanka is covered with a network of thousands of man-made lakes and ponds, known locally as “tanks,” numbering more than 25,000. Some are in the functional mode and others still remaining abandoned type. Many are thousands of years old and almost all show a high degree of sophistication in their construction and design. Sri Lanka's tanks are fascinatingly distributed in the cascades of tanks one below the other conserving water and soil and most effectively, acting as buffers against droughts while giving due consideration to maintaining the ecosystem equilibrium.

Details

Water Communities
Type: Book
ISBN: 978-1-84950-699-1

Book part
Publication date: 22 August 2014

Rohit Setty

The focus and goal of this chapter is to systematically detail how the “cascade” system is organized and how it operates by coordinating current research. To do so, this chapter…

Abstract

The focus and goal of this chapter is to systematically detail how the “cascade” system is organized and how it operates by coordinating current research. To do so, this chapter first builds an understanding of the historical conditions that forged the “cascade” system, then turns to how the system operates – charting its affordances and limitations through others’ research – and then discusses what opportunities can be leveraged to support teachers’ work. In doing so, this chapter provides relevant information and documentation about the “cascade” system so that readers can understand how this system currently works and what is possible. Two interpretations are made from the analysis of current research. First, the “cascade” is overwrought with voices, and the participants overwhelmed; and second, the “cascade” fosters an untenable view of how people learn and what constitutes teaching. Increasingly, teachers and their education are being widely recognized as central to the fortunes of schoolchildren. In India, a significant amount of attention is being paid to teacher education more than ever before. For example, the recent 5-year planning and operations budget is being touted as the “Teacher Education Plan.” Thus, probing the existing system and its norms and practices is vital to ensuring this attention isn’t frittered away and is put toward helping teachers step up to the challenge of providing all students rich opportunities to learn.

Details

Annual Review of Comparative and International Education 2014
Type: Book
ISBN: 978-1-78350-453-4

Keywords

Article
Publication date: 4 April 2023

Chao Ren, Xiaoxing Liu and Ziyan Zhu

The purpose of this paper is to test the invulnerability of the guarantee network at the equilibrium point.

Abstract

Purpose

The purpose of this paper is to test the invulnerability of the guarantee network at the equilibrium point.

Design/methodology/approach

This paper introduces a tractable guarantee network model that captures the invulnerability of the network in terms of cascade-based attack. Furthermore, the equilibrium points are introduced for banks to determine loan origination.

Findings

The proposed approach not only develops equilibrium analysis as an extended perspective in the guarantee network, but also applies cascading failure method to construct the guarantee network. The equilibrium points are examined by simulating experiment. The invulnerability of the guarantee network is quantified by the survival of firms in the simulating progress.

Research limitations/implications

There is less study in equilibrium analysis of the guarantee network. Additionally, cascading failure model is expressed in the presented approach. Moreover, agent-based model can be extended in generating the guarantee network in the future study.

Originality/value

The approach of this paper presents a framework to analyze the equilibrium of the guarantee network. For this, the systemic risk of the whole guarantee network and each node's contribution are measured to predict the probability of default on cascading failure. Focusing on cascade failure process based on equilibrium point, the invulnerability of the guarantee network can be quantified.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 March 2005

Lynn Chmelir

To report and analyze transaction data over a four‐year period for patron‐initiated borrowing via the Cascade union catalog as well as transaction data for traditional ILL in a…

791

Abstract

Purpose

To report and analyze transaction data over a four‐year period for patron‐initiated borrowing via the Cascade union catalog as well as transaction data for traditional ILL in a consortium of six academic libraries in Washington State.

Design/methodology/approach

Transaction data for patron‐initiated borrowing via the Cascade union catalog were gathered from statistics produced by the Inn‐Reach software. Data for ILL were collected via a survey of libraries’ staff. Data for returnables and copies were analyzed at the consortium and institutional level.

Findings

In the third year of patron‐initiated borrowing, traditional ILL transactions for returnables had decreased 21 per cent consortium‐wide, the total number of transactions for returnables had increased 271.9 per cent, and the transactions for copies remained steady. Although the borrowing and lending patterns at the six libraries varied, each loaned and borrowed more returnables via patron‐initiated borrowing than via traditional ILL.

Research limitations/implications

This study describes activity at a single consortium of only six libraries. Since the Cascade libraries have now merged into a larger consortium, the Orbis Cascade Alliance, it would be interesting to collect and analyze new data from the larger group to see if patterns have changed.

Practical implications

The increased volume of returnables delivered to users in this consortium suggests that patron‐initiated borrowing is an effective method for resource sharing. Traditional ILL remains a necessary alternative for copies and books not available within the consortium.

Originality/value

This is the first study to examine consortium‐wide transaction data for both patron‐initiated borrowing and traditional interlibrary loan for a sustained period of time.

Details

Interlending & Document Supply, vol. 33 no. 1
Type: Research Article
ISSN: 0264-1615

Keywords

Article
Publication date: 13 June 2022

Wang Jianhong and Ricardo A. Ramirez-Mendoza

The purpose of this paper extends the authors’ previous contributions on aircraft system identification, such as open loop identification or closed loop identification, to cascade

Abstract

Purpose

The purpose of this paper extends the authors’ previous contributions on aircraft system identification, such as open loop identification or closed loop identification, to cascade system identification. Because the cascade system is one special network system, existing in lots of practical engineers, more unknown systems are needed to identify simultaneously within the statistical environment with the probabilistic noises. Consider this problem of cascade system identification, prediction error method is proposed to identify three unknown systems, which are parameterized by three unknown parameter vectors. Then the cascade system identification is transferred as one parameter identification problem, being solved by the online subgradient descent algorithm. Furthermore, the nonparametric estimation is proposed to consider the general case without any parameterized process. To make up the identification mission, model validation process is given to show the asymptotic interval of the identified parameter. Finally, simulation example confirms the proposed theoretical results.

Design/methodology/approach

Firstly, aircraft system identification is reviewed through the understanding about system identification and advances in control theory, then cascade system identification is introduced to be one special network system. Secondly, for the problem of cascade system identification, prediction error method and online subgradient decent algorithm are combined together to identify the cascade system with the parameterized systems. Thirdly from the point of more general completeness, another way is proposed to identify the nonparametric estimation, then model validation process is added to complete the whole identification mission.

Findings

This cascade system corresponds to one network system, existing in lots of practice, such as aircraft, ship and robot, so it is necessary to identify this cascade system, paving a way for latter network system identification. Parametric and nonparametric estimations are all studied within the statistical environment. Then research on bounded noise is an ongoing work.

Originality/value

To the best of the authors’ knowledge, research on aircraft system identification only concern on open loop and closed loop system identification, no any identification results about network system identification. This paper considers cascade system identification, being one special case on network system identification, so this paper paves a basic way for latter more advanced system identification and control theory.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 11 November 2014

Qihua Liu and Liyi Zhang

The purpose of this paper is to examine information cascades in the context of users’ e-book reading behavior and differentiate it from alternative factors that lead to herd…

Abstract

Purpose

The purpose of this paper is to examine information cascades in the context of users’ e-book reading behavior and differentiate it from alternative factors that lead to herd behavior, such as network externalities and word-of-mouth effects.

Design/methodology/approach

This paper constructed panel data using information concerning 226 e-books in 30 consecutive days from Sina.com’s reading channel (Book.Sina.com.cn) from October 2, 2013, to October 31, 2013 of the same year in China. A multinomial logit market-share model was employed.

Findings

E-books’ ranking has a significant impact on their market share, as predicted by informational cascades theory. Higher ranking e-books’ clicks will see a greater increase as a result of an increase in clicks ranking. Due to the information cascades effect, review volume had no impact on the market share of popular e-books. Total votes had a powerful impact on the market share of e-books, showing that once information cascade occurred, it could be enhanced by the increase in total votes. The total clicks of e-books had a significant impact on their market share, suggesting that online reading behavior would be influenced by network externalities.

Practical implications

As important information, the ranking or popularity of e-books should be carefully considered by online reading web sites, publishers, and authors. It is not enough for the authors and publishers of e-books to simply pay attention to the content. They should design their marketing strategies to allow network externalities and informational cascades to work for them, not against them. Online reading web sites should also focus on eliminating certain behavior, such as “brush clicks” and “brush votes,” in order to prevent an undesirable information cascade due to false information.

Originality/value

To the best of the knowledge, this is the first study to examine information cascades in the context of users’ e-book reading behavior. Moreover, this study can help other researchers by utilizing a large sample of daily data from one of the earliest online reading platforms in China.

Details

Library Hi Tech, vol. 32 no. 4
Type: Research Article
ISSN: 0737-8831

Keywords

Article
Publication date: 15 May 2017

Joohyun Kim, Ohsung Kwon and Duk Hee Lee

The purpose of this paper is to explore how hubs’ social influence on social network decisions can cause the behavior of information cascades in a market.

Abstract

Purpose

The purpose of this paper is to explore how hubs’ social influence on social network decisions can cause the behavior of information cascades in a market.

Design/methodology/approach

The authors establish understanding of the fundamental mechanism of information cascades through a computational simulation approach.

Findings

Eigenvector centrality, betweenness centrality, and PageRank are statistically correlated with the occurrence of information cascades among agents; the hubs’ incorrect decisions in the early diffusion stage can significantly cause misled shift cascades; and the bridge role of hubs is more influential than their pivotal position role in the process of misled shift cascades.

Originality/value

This implication can be extendable in the field of marketing, sequential voting, and technology, or innovation adoption.

Details

Management Decision, vol. 55 no. 4
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 12 March 2018

Oksana Doherty

The purpose of this paper is to review recent contributions to the theoretical and empirical literature on informational cascades.

Abstract

Purpose

The purpose of this paper is to review recent contributions to the theoretical and empirical literature on informational cascades.

Design/methodology/approach

This paper reviews and synthesises the existing literature, methodologies and evidence on informational cascades.

Findings

Many financial settings foster situations where informational cascades and herding are likely. Cascades remain mainly an area of experimental research, leaving the empirical evidence inconclusive. Existing measures have limitations that do not allow for a direct test of cascading behaviour. More accurate models and methods for empirical testing of informational cascades could provide more conclusive evidence on the matter.

Practical implications

Outlined findings have implications for designing policies and regulatory requirements, as well as for the design of collective decisions processes.

Originality/value

The paper reviews and critiques existing theory; it summarises the recent laboratory and empirical evidence and identifies issues for future research. Most of other theoretical work reviews informational cascades as a subsection of herding. This paper focusses on informational cascades specifically. It distinguishes between informational cascade and herding. The paper also reviews most recent empirical evidence on cascades, presents review and synthesis of the theoretical and empirical development on information cascades up to date, and reviews the model of informational cascades with model criticism.

Details

Review of Behavioral Finance, vol. 10 no. 1
Type: Research Article
ISSN: 1940-5979

Keywords

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