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1 – 10 of 17Alia Al-Ghosoun, Ashraf S. Osman and Mohammed Seaid
The purpose of this study is twofold: first, to derive a consistent model free-surface runup flow problems over deformable beds. The authors couple the nonlinear one-dimensional…
Abstract
Purpose
The purpose of this study is twofold: first, to derive a consistent model free-surface runup flow problems over deformable beds. The authors couple the nonlinear one-dimensional shallow water equations, including friction terms for the water free-surface and the two-dimensional second-order solid elastostatic equations for the bed deformation. Second, to develop a robust hybrid finite element/finite volume method for solving free-surface runup flow problems over deformable beds. The authors combine the finite volume for free-surface flows and the finite element method for bed elasticity.
Design/methodology/approach
The authors propose a new model for wave runup by static deformation on seabeds. The model consists of the depth-averaged shallow water system for the water free-surface coupled to the second-order elastostatic formulation for the bed deformation. At the interface between the water flow and the seabed, transfer conditions are implemented. Here, hydrostatic pressure and friction forces are considered for the elastostatic equations, whereas bathymetric forces are accounted for in the shallow water equations. As numerical solvers, the authors propose a well-balanced finite volume method for the flow system and a stabilized finite element method for elastostatics.
Findings
The developed coupled depth-averaged shallow water system and second-order solid elastostatic system is well suited for modeling wave runup by deformation on seabeds. The derived coupling conditions at the interface between the water flow and the bed topography resolve well the condition transfer between the two systems. The proposed hybrid finite volume element method is accurate and efficient for this class of models. The novel technique used for wet/dry treatment accurately captures the moving fronts in the computational domain without generating nonphysical oscillations. The presented numerical results demonstrate the high performance of the proposed methods.
Originality/value
Enhancing modeling and computations for wave runup problems is at an early stage in the literature, and it is a new and exciting area of research. To the best of our knowledge, solving wave runup problems by static deformation on seabeds using a hybrid finite volume element method is presented for the first time. The results of this research study, and the research methodologies, will have an important influence on a range of other scientists carrying out research in related fields.
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To provide data on the tsunami hazard of the Mediterranean region, to outline the Maltese Islands specific tsunami risks.
Abstract
Purpose
To provide data on the tsunami hazard of the Mediterranean region, to outline the Maltese Islands specific tsunami risks.
Design/methodology/approach
The physics of tsunami and the tsunami magnitude scales are first introduced. The Mediterranean tsunami characteristics are introduced by reference to sources (1962‐2003). Following this the Mediterranean tsunami vulnerability assessment is undertaken. This then narrows down to assessing the Maltese tsunami hazards with reference to various newspaper articles, with finally a risk assessment for Malta tsunami exposure calculated.
Findings
Considering the high loss of life occurring in the Indian Ocean catastrophic tsunami, tsunami awareness hazards are to be kept ongoing whilst Malta should form part of an expected European Tsunami Warning System.
Practical implications
Planning is to consider various options available including tsunami barriers, evacuation paths, buildings with vertical evacuation facilities. It would be more prudent to work with nature by moving all inessential structures further into the interior and to protect the shoreline with suitable vegetation.
Originality/value
Creates a Mediterranean/Maltese awareness to tsunami hazards/risks in a highly developed tourist region.
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Mario Ordaz, Mario Andrés Salgado-Gálvez, Benjamín Huerta, Juan Carlos Rodríguez and Carlos Avelar
The development of multi-hazard risk assessment frameworks has gained momentum in the recent past. Nevertheless, the common practice with openly available risk data sets, such as…
Abstract
Purpose
The development of multi-hazard risk assessment frameworks has gained momentum in the recent past. Nevertheless, the common practice with openly available risk data sets, such as the ones derived from the United Nations Office for Disaster Risk Reduction Global Risk Model, has been to assess risk individually for each peril and afterwards aggregate, when possible, the results. Although this approach is sufficient for perils that do not have any interaction between them, for the cases where such interaction exists, and losses can be assumed to occur simultaneously, there may be underestimation of losses. The paper aims to discuss these issues.
Design/methodology/approach
This paper summarizes a methodology to integrate simultaneous losses caused by earthquakes and tsunamis, with a peril-agnostic approach that can be expanded to other hazards. The methodology is applied in two relevant locations in Latin America, Acapulco (Mexico) and Callao (Peru), considering in each case building by building exposure databases with portfolios of different characteristics, where the results obtained with the proposed approach are compared against those obtained after the direct aggregation of individual losses.
Findings
The fully probabilistic risk assessment framework used herein is the same of the global risk model but applied at a much higher resolution level of the hazard and exposure data sets, showing its scalability characteristics and the opportunities to refine certain inputs to move forward into decision-making activities related to disaster risk management and reduction.
Originality/value
This paper applies for the first time the proposed methodology in a high-resolution multi-hazard risk assessment for earthquake and tsunami in two major coastal cities in Latin America.
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Udari Gunarathna, Chaminda Senarathna Bandara, Ranjith Dissanayake and Harsha Munasinghe
The lessons learned from the 2004 tsunami phenomenon fueled the government and other local authorities to strengthen the legitimate background to mitigate such devastation in…
Abstract
Purpose
The lessons learned from the 2004 tsunami phenomenon fueled the government and other local authorities to strengthen the legitimate background to mitigate such devastation in future events. This study aims to propose a standardized tsunami-resilient construction guideline for Sri Lanka by integrating existing local and international standards.
Design/methodology/approach
A comprehensive literature survey was carried out to undertake the study, with a wide-ranging content and thematic analysis of existing tsunami-resilient construction aspects in Sri Lanka. Integrating all existing guidelines with international standards, finally, a consolidated guideline with significant tsunami-resilient building aspects was proposed for stakeholders involved with the resilient built environment in tsunami-prone areas, particularly during the building construction in the coastal belt.
Findings
The existing tsunami-resilient guidelines in Sri Lanka follow similar aspects but in different dimensions. Compared to the international standards, few significant aspects create a gap in local guidelines. Thus, the findings demonstrated that the existing local guidelines must be modified and strengthened by mainstreaming into international practices.
Research limitations/implications
Existing guidelines are more concerned with structural aspects. Nevertheless, proper integration of local and international guidelines would be more favorable to minimizing existing local guidelines’ gaps. Further, a standardized tsunami-resilient building guideline would be a referring document for all stakeholders in tsunami-resilient constructions.
Practical implications
By aligning local guidelines with international standards, the reliability of the guidelines will be increased and direct the built environment to quality disaster-resilient constructions.
Social implications
Through a standardized guideline, the community can rely on tsunami-resilient construction in coastal cities.
Originality/value
The consolidated guideline further contains the essentials of city resilience in tsunamis and would be an excellent reference for relevant stakeholders than aligning with several guidelines.
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The purpose of this paper is to determine whether information produced in the takeover process or changes in firm characteristics after takeovers affect bidder liquidity.
Abstract
Purpose
The purpose of this paper is to determine whether information produced in the takeover process or changes in firm characteristics after takeovers affect bidder liquidity.
Design/methodology/approach
This paper compares the liquidity changes for bidders that complete their takeovers (successful bidders) and bidders that eventually withdraw their takeover attempts (unsuccessful bidders) to disentangle the information production hypothesis and the firm characteristics hypothesis. The authors use both media mentions and changes in the standard deviation of market model residuals to proxy for the information produced in the takeover process, intraday data to construct the liquidity measures, and regression analyses to examine the determinants of bidder liquidity changes.
Findings
This paper finds that unsuccessful bidders experience no less information production than successful bidders during the takeover process, but only successful bidders enjoy liquidity improvements. Once the authors control for the changes in firm characteristics, whether a takeover is successful or not no longer affects bidder liquidity. Moreover, information production reduces information asymmetry for successful Nasdaq bidders but not NYSE bidders. These findings collectively support the firm characteristics hypothesis but also suggest a role of information production on firms with higher information asymmetry.
Originality/value
This paper provides the direct evidence that the information produced in the takeover process does not lead to liquidity improvements of the bidders. It also supplements existing literature with a more comprehensive sample and sheds light on how acquisition withdrawals affect firms' liquidity.
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Frederick Davis, Thomas Walker and Linyi Zhou
Within the context of mergers and acquisitions, the purpose of this paper is to clarify the relationship between the deal initiator and various outcomes of the deal, particularly…
Abstract
Purpose
Within the context of mergers and acquisitions, the purpose of this paper is to clarify the relationship between the deal initiator and various outcomes of the deal, particularly in consideration of the cash position of the acquiring firm.
Design/methodology/approach
Using hand-collected deal initiation data from various filings on the Securities Exchange Commission EDGAR online database, this paper performs a series of event study analyses, multivariate analyses, a Heckman two-step estimation procedure, and an instrumental variable approach to examine merger outcomes.
Findings
This paper finds that many merger and acquisition (M&A) outcomes (target and acquirer announcement returns, acquirer long-run returns, premiums, and the method of payment) are significantly related to deal initiation, particularly in consideration of the cash position of the acquiring firm. Overall, evidence is seen as consistent with the theory that “lemons” selectively approach cash-rich acquirers, often to the acquirers’ detriment.
Originality/value
This paper finds that target-initiated deals are not necessarily associated with poorer transaction outcomes for targets as contemporaneous studies suggest, and presents the first empirical evidence of M&A outcomes related to the deal initiator which are dependent on the cash position of the acquiring firm.
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The increasing frequency and intensity of the extreme weather events could cause devastating consequences in tourism. Climate change–related extreme weather events and their…
Abstract
Purpose
The increasing frequency and intensity of the extreme weather events could cause devastating consequences in tourism. Climate change–related extreme weather events and their relation to tourism is an emerging field for education and research. The purpose of this study is to categorize the impact of climate change on tourist destinations with regard to extreme weather-related risks in outdoor recreation and tourism. Managerial implications for policymakers and stakeholders are discussed.
Design/methodology/approach
To outline the risks from climate change associated with tourism, this study uses the Prisma analysis for identification, screening, checking for eligibility and finding relevant literature for further categorization.
Findings
Based on a thoroughly examination of relevant literature, risks and threats posed by climate change could be categorized into following four areas: reduced experiential value in outdoor winter recreation; reduced value in beach scenery and comfort; land degradation and reduced biodiversity; and reduced value in personal safety and comfort in tourism. It also focuses on the significance of using big data applications in catastrophic disaster management and risk reduction. Recommendations with technology and data analytics to continuously improve the disaster management process in tourism education are provided based on findings of this study.
Originality/value
Primary contributions of this study include the following: providing a summarized overview of the risks associated with climate change in terms of tourist experiential value for educational implications; and revealing the role of data analytics in disaster management in the context of tourism and climate change for tourism education.
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A tax based on land value is in many ways ideal, but many economists dismiss it by assuming it could not raise enough revenue. Standard sources of data omit much of the potential…
Abstract
Purpose
A tax based on land value is in many ways ideal, but many economists dismiss it by assuming it could not raise enough revenue. Standard sources of data omit much of the potential tax base, and undervalue what they do measure. The purpose of this paper is to present more comprehensive and accurate measures of land rents and values, and several modes of raising revenues from them besides the conventional property tax.
Design/methodology/approach
The paper identifies 16 elements of land's taxable capacity that received authorities either trivialize or omit. These 16 elements come in four groups.
Findings
In Group A, Elements 1‐4 correct for the downward bias in standard sources. In Group B, Elements 5‐10 broaden the concepts of land and rent beyond the conventional narrow perception, while Elements 11‐12 estimate rents to be gained by abating other kinds of taxes. In Group C, Elements 13‐14 explain how using the land tax, since it has no excess burden, uncaps feasible tax rates. In Group D, Elements 15‐16 define some moot possibilities that may warrant further exploration.
Originality/value
This paper shows how previous estimates of rent and land values have been narrowly limited to a fraction of the whole, thus giving a false impression that the tax capacity is low. The paper adds 14 elements to the traditional narrow “single tax” base, plus two moot elements advanced for future consideration. Any one of these 16 elements indicates a much higher land tax base than economists commonly recognize today. Taken together they are overwhelming, and cast an entirely new light on this subject.
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Perumandla Karunakar and Snehashish Chakraverty
The purpose of this paper is to find the solution of classical nonlinear shallow-water wave (SWW) equations in particular to the tsunami wave propagation in crisp and interval…
Abstract
Purpose
The purpose of this paper is to find the solution of classical nonlinear shallow-water wave (SWW) equations in particular to the tsunami wave propagation in crisp and interval environment.
Design/methodology/approach
Homotopy perturbation method (HPM) has been used for handling crisp and uncertain differential equations governing SWW equations.
Findings
The wave height and depth-averaged velocity of a tsunami wave in crisp and interval cases have been obtained.
Originality/value
Present results by HPM are compared with the existing solution (in crisp case), and they are found to be in good agreement. Also, the residual error of the solutions is found for the convergence conformation and reliability of the present results.
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