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Abstract

Details

Handbook of Microsimulation Modelling
Type: Book
ISBN: 978-1-78350-570-8

Article
Publication date: 14 October 2009

Pietro De Giovanni

The purpose of this paper is to investigate the state of the art in static and dynamic games (or inter‐firm relationships). This research area has changed significantly…

Abstract

Purpose

The purpose of this paper is to investigate the state of the art in static and dynamic games (or inter‐firm relationships). This research area has changed significantly over the last 25 years through the development of phenomena such as the supply chain and the progressive overcoming of monopolistic and oligopolistic frameworks. By exploring the state of the art in inter‐firm relationships, this paper aims to identify the most suitable research methods to be used by future research in this domain and to highlight the major areas under investigation.

Design/methodology/approach

This research adopts both qualitative and quantitative approaches. The qualitative approach describes the technical differences between static and dynamic methods and gives evidence of their appropriateness when applied to a game. Quantitative analysis transforms some of the information extracted from the qualitative analysis into categorical variables in order to obtain an indication of the major issues still to be addressed.

Findings

The resulting findings identify the extent of the use of static and dynamic modelling in previous research and how their use has changed over time, what resolution methods need to be applied when investigating inter‐firm relationship, what features influence this decision and what research areas still remain unexplored.

Originality/value

The existing literature on the modelling of static and dynamic games lacks an exhaustive review. Several contributions investigate the literature on inter‐firms relationships and review numerous issues, but focus only on static or dynamic modelling. This paper fills this gap by reviewing a number of theoretical papers.

Details

European Business Review, vol. 21 no. 6
Type: Research Article
ISSN: 0955-534X

Keywords

Article
Publication date: 19 January 2015

Chao Wang, Guofu Yin, Zhengyu Zhang, Shuiliang Wang, Tao Zhao, Yan Sun and Dangguo Yang

– The purpose of this paper is to introduce a novel method for developing static aeroelastic models based on rapid prototyping for wind tunnel testing.

Abstract

Purpose

The purpose of this paper is to introduce a novel method for developing static aeroelastic models based on rapid prototyping for wind tunnel testing.

Design/methodology/approach

A metal frame and resin covers are applied to a static aeroelastic wind tunnel model, which uses the difference of metal and resin to achieve desired stiffness distribution by the stiffness similarity principle. The metal frame is made by traditional machining, and resin covers are formed by stereolithgraphy. As demonstrated by wind tunnel testing and stiffness measurement, the novel method of design and fabrication of the static aeroelastic model based on stereolithgraphy is practical and feasible, and, compared with that of the traditional static elastic model, is prospective due to its lower costs and shorter period for its design and production, as well as avoiding additional stiffness caused by outer filler.

Findings

This method for developing static aeroelastic wind tunnel model with a metal frame and resin covers is feasible, especially for aeroelastic wind tunnel models with complex external aerodynamic shape, which could be accurately constructed based on rapid prototypes in a shorter time with a much lower cost. The developed static aeroelastic aircraft model with a high aspect ratio shows its stiffness distribution in agreement with the design goals, and it is kept in a good condition through the wind tunnel testing at a Mach number ranging from 0.4 to 0.65.

Research limitations/implications

The contact stiffness between the metal frame and resin covers is difficult to calculate accurately even by using finite element analysis; in addition, the manufacturing errors have some effects on the stiffness distribution of aeroelastic models, especially for small-size models.

Originality/value

The design, fabrication and ground testing of aircraft static aeroelastic models presented here provide accurate stiffness and shape stimulation in a cheaper and sooner way compared with that of traditional aeroelastic models. The ground stiffness measurement uses the photogrammetry, which can provide quick, and precise, evaluation of the actual stiffness distribution of a static aeroelastic model. This study, therefore, expands the applications of rapid prototyping on wind tunnel model fabrication, especially for the practical static aeroelastic wind tunnel tests.

Details

Rapid Prototyping Journal, vol. 21 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 31 May 2007

Rongrong Zhang and Yoshio Kanazaki

The purpose of this paper is to test static tradeoff against pecking order models of capital structure in Japanese firms.

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Abstract

Purpose

The purpose of this paper is to test static tradeoff against pecking order models of capital structure in Japanese firms.

Design/methodology/approach

The static tradeoff and pecking order models are tested on a sample of 1,325 non‐financial Japanese firms between 2002 and 2006.

Findings

Empirical results prove that both models can explain some part of the capital structure. The static tradeoff model shows that firm leverage is affected by several determinants, and the pecking order model displays similar movements between net debt retired and financial surplus. However, both models have shortcomings. The static tradeoff model fails to explain the negative correlation between profitability and firm leverage, and the pecking order model fails to explain the low deficit coefficient.

Originality/value

The paper, because of the inconsistent results in prior studies, tests static tradeoff against pecking order models, with the data of Japanese firms.

Details

International Journal of Accounting & Information Management, vol. 15 no. 2
Type: Research Article
ISSN: 1834-7649

Keywords

Article
Publication date: 24 July 2020

Lafaiet Silva, Nádia Félix Silva and Thierson Rosa

This study aims to analyze Kickstarter data along with social media data from a data mining perspective. Kickstarter is a crowdfunding financing plataform and is a form of…

Abstract

Purpose

This study aims to analyze Kickstarter data along with social media data from a data mining perspective. Kickstarter is a crowdfunding financing plataform and is a form of fundraising and is increasingly being adopted as a source for achieving the viability of projects. Despite its importance and adoption growth, the success rate of crowdfunding campaigns was 47% in 2017, and it has decreased over the years. A way of increasing the chances of success of campaigns would be to predict, by using machine learning techniques, if a campaign would be successful. By applying classification models, it is possible to estimate if whether or not a campaign will achieve success, and by applying regression models, the authors can forecast the amount of money to be funded.

Design/methodology/approach

The authors propose a solution in two phases, namely, launching and campaigning. As a result, models better suited for each point in time of a campaign life cycle.

Findings

The authors produced a static predictor capable of classifying the campaigns with an accuracy of 71%. The regression method for phase one achieved a 6.45 of root mean squared error. The dynamic classifier was able to achieve 85% of accuracy before 10% of campaign duration, the equivalent of 3 days, given a campaign with 30 days of length. At this same period time, it was able to achieve a forecasting performance of 2.5 of root mean squared error.

Originality/value

The authors carry out this research presenting the results with a set of real data from a crowdfunding platform. The results are discussed according to the existing literature. This provides a comprehensive review, detailing important research instructions for advancing this field of literature.

Details

International Journal of Web Information Systems, vol. 16 no. 4
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 4 January 2016

Dominik B. Schwinn

– The purpose of this paper is to present a methodology for the evaluation of transport aircraft fuselages constructed in a semi-monocoque design.

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Abstract

Purpose

The purpose of this paper is to present a methodology for the evaluation of transport aircraft fuselages constructed in a semi-monocoque design.

Design/methodology/approach

A fuselage barrel was computed statically and dynamically using finite element methods. Static analysis was conducted using a global/local approach in which the section loads of the global model were used as load introduction in the local model. Subsequently, a crash analysis was performed, and the results from both disciplines were evaluated by either an optimization or parameter variation algorithm.

Findings

The presented process chain has been developed for use in preliminary design stages to assess aircraft configurations with regard to statics and dynamics. Parameter variation and optimization were conducted, proving functionality of the methodology.

Research limitations/implications

In this early stage of methodology development only one exemplary static load case is considered and the fuselage design is limited to a constant section.

Practical implications

The presented process chain shows an approach to couple different disciplines to reduce the analysis time in aircraft preliminary design phase.

Originality/value

This methodology couples static design and crashworthiness aspects at an early design stage to avoid time- and cost-intensive redesign in subsequent detailed design stages. The process chain introduced in this paper uses a parameterized approach, making this methodology applicable for each fuselage in semi-monocoque design.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 88 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 7 August 2009

Grzegorz Drałus and Jerzy Świątek

The purpose of this paper is to present research in the area of the modeling of complex systems using feed‐forward neural network.

Abstract

Purpose

The purpose of this paper is to present research in the area of the modeling of complex systems using feed‐forward neural network.

Design/methodology/approach

Applications of multilayer neural networks with supervisor learning on the own simulator program wrote in Borland® Pascal Language. Series‐parallel identification method is applied. Tapped delay lines (TDL) in static neural networks for modeling of dynamic plants are used. Gradient and heuristic learning algorithms are applied. Three kinds of calibration of learning and testing data are used.

Findings

This paper illustrates that feed‐forward multilayer neural networks can model complex systems. Feed‐forward multilayer neural networks with TDL can be used to build global dynamic models of complex systems. It is possible to compare the quality both models.

Research limitations/implications

The learning and testing data from real systems to tune neuronal models require use of calibrating these data to range 0‐1.

Practical implications

The models quality depends on kind of calibration learning data from real system and depends on kind of learning algorithms.

Originality/value

The method and the learning algorithms discussed in the paper can be used to create global models of complex systems. The multilayer neural network with TDL can be used to model complex dynamic systems with low dynamics.

Details

Kybernetes, vol. 38 no. 7/8
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 11 May 2010

Jonathan B. Dressler and Jeffrey R. Stokes

This paper aims to identify factors that affect agricultural mortgage default and prepayment.

Abstract

Purpose

This paper aims to identify factors that affect agricultural mortgage default and prepayment.

Design/methodology/approach

Using a sample of farm credit system loans, prepayment and default are modeled as competing risks with potentially non‐stationary covariates using a statistical/econometric technique called survival snalysis (SA).

Findings

The analysis suggests that the primary drivers of prepayment and default are the rate of interest charged by the lender at origination and the borrower's current ratio at origination. Tests of the existence of a geographic effect indicate that despite bank management belief to the contrary, branches may not be homogeneous.

Research limitations/implications

This analysis would be improved if more data were available in an easily obtainable manner to control for unobserved heterogeneity. Unobserved heterogeneity or incomplete specification within a model can be problematic. Inferences among regression coefficients can be problematic in that the estimates have inflated variances and unreliable test statistics. In addition, more frequent measures of the time‐varying covariates could be obtained to improve upon the SA models presented above. Future analyses could also incorporate other sections of the agricultural credit association portfolio, as well as a comparison to variable rate notes. One other logical next step would be to obtain loan collateral values to obtain estimates of the exposure at default, and the loss given default, or the estimates needed for the advanced internal ratings based approach described in the Basel Accords.

Originality/value

This paper provides a method for lenders to measure and model mortgage termination, an important consideration for risk managers when determining capital adequacy described in the Basel Accords.

Details

Agricultural Finance Review, vol. 70 no. 1
Type: Research Article
ISSN: 0002-1466

Keywords

Article
Publication date: 23 January 2019

Tamás Nyitrai

The purpose of this paper is to enhance the predictive power of bankruptcy prediction models by taking the past values of firms’ financial ratios as benchmark. For this…

Abstract

Purpose

The purpose of this paper is to enhance the predictive power of bankruptcy prediction models by taking the past values of firms’ financial ratios as benchmark. For this purpose, the paper proposes an indicator variable expressing the time trends of financial ratios.

Design/methodology/approach

The proposed measure uses the minimum and the maximum of financial ratios from the previous period as benchmarks in order to give a more complete picture about the present financial performance of firms. The most popular classification methods of bankruptcy prediction were employed: discriminant analysis, logistic regression, decision trees. Sample specific results and conclusions were avoided by applying tenfold stratified cross-validation.

Findings

The empirical results suggest that the proposed measure can increase the predictive performance of bankruptcy prediction models compared to models based solely on static financial ratios. The results gave evidence for the fact that the firms’ past financial performance is a useful benchmark for evaluating the risk of future insolvency.

Originality/value

The proposed concept is completely new to the literature and practice of bankruptcy prediction. Similar concept has not been published to date. The suggested dynamization approach has three important advantages. It is easy to compute from time series of financial ratios. It is applicable within any classifier irrespective of its mathematical background. The performance of models can be enhanced without the necessity of giving up the interpretability of bankruptcy models, so the proposed measure may play very important role in the practice of credit scoring modeling as well.

Details

Benchmarking: An International Journal, vol. 26 no. 1
Type: Research Article
ISSN: 1463-5771

Keywords

Article
Publication date: 24 July 2009

Lars Bækgaard

The purpose of the paper is to obtain insight into, and provide practical advice for, event‐based conceptual modeling.

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Abstract

Purpose

The purpose of the paper is to obtain insight into, and provide practical advice for, event‐based conceptual modeling.

Design/methodology/approach

The paper analyzes a set of event concepts and uses the results to formulate a conceptual event model that is used to identify guidelines for creation of dynamic process models and static information models.

Findings

The paper characterizes events as short‐duration processes that have participants, consequences, and properties, and that may be modeled in terms of information structures. The conceptual event model is used to characterize a variety of event concepts and it is used to illustrate how events can be used to integrate dynamic modeling of processes and static modeling of information structures.

Originality/value

The results are unique in the sense that no other general event concept has been used to unify a similar broad variety of seemingly incompatible event concepts. The general event concept can be used to improve dynamic and static modeling.

Details

Business Process Management Journal, vol. 15 no. 4
Type: Research Article
ISSN: 1463-7154

Keywords

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