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Article
Publication date: 1 December 2004

Sanjay Rawat, V.P. Gulati and Arun K. Pujari

This paper discusses a new similarity measure for the anomaly‐based intrusion detection scheme using sequences of system calls. With the increasing frequency of new…

Abstract

This paper discusses a new similarity measure for the anomaly‐based intrusion detection scheme using sequences of system calls. With the increasing frequency of new attacks, it is getting difficult to update the signatures database for misuse‐based intrusion detection system (IDS). While anomaly‐based IDS has a very important role to play, the high rate of false positives remains a cause for concern. Defines a similarity measure that considers the number of similar system calls, frequencies of system calls and ordering‐of‐system calls made by the processes to calculate the similarity between the processes. Proposes the use of Kendall Tau distance to calculate the similarity in terms of ordering of system calls in the process. The k nearest neighbor (kNN) classifier is used to categorize a process as either normal or abnormal. The experimental results, performed on 1998 DARPA data, are very promising and show that the proposed scheme results in a high detection rate and low rate of false positives.

Details

Information Management & Computer Security, vol. 12 no. 5
Type: Research Article
ISSN: 0968-5227

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Article
Publication date: 16 December 2019

Francisco-Javier Granados-Ortiz, Joaquin Ortega-Casanova and Choi-Hong Lai

Impinging jets have been widely studied, and the addition of swirl has been found to be beneficial to heat transfer. As there is no literature on Reynolds-averaged Navier…

Abstract

Purpose

Impinging jets have been widely studied, and the addition of swirl has been found to be beneficial to heat transfer. As there is no literature on Reynolds-averaged Navier Stokes equations (RANS) nor experimental data of swirling jet flows generated by a rotating pipe, the purpose of this study is to fill such gap by providing results on the performance of this type of design.

Design/methodology/approach

As the flow has a different behaviour at different parts of the design, the same turbulent model cannot be used for the full domain. To overcome this complexity, the simulation is split into two coupled stages. This is an alternative to use the costly Reynold stress model (RSM) for the rotating pipe simulation and the SST k-ω model for the impingement.

Findings

The addition of swirl by means of a rotating pipe with a swirl intensity ranging from 0 up to 0.5 affects the velocity profiles, but has no remarkable effect on the spreading angle. The heat transfer is increased with respect to a non-swirling flow only at short nozzle-to-plate distances H/D < 6, where H is the distance and D is the diameter of the pipe. For the impinging zone, the highest average heat transfer is achieved at H/D = 5 with swirl intensity S = 0.5. This is the highest swirl studied in this work.

Research limitations/implications

High-fidelity simulations or experimental analysis may provide reliable data for higher swirl intensities, which are not covered in this work.

Practical implications

This two-step approach and the data provided is of interest to other related investigations (e.g. using arrays of jets or other surfaces than flat plates).

Originality/value

This paper is the first of its kind RANS simulation of the heat transfer from a flat plate to a swirling impinging jet flow issuing from a rotating pipe. An extensive study of these computational fluid dynamics (CFD) simulations has been carried out with the emphasis of splitting the large domain into two parts to facilitate the use of different turbulent models and periodic boundary conditions for the flow confined in the pipe.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 21 March 2016

Jorge Gonzalez Prada, Aitor Cazon, Josu Carda and Ander Aseguinolaza

This paper aims to focus on the design, analysis and additive manufacturing (AM) with two different technologies of an accelerator pedal for the Formula Student 2014…

Abstract

Purpose

This paper aims to focus on the design, analysis and additive manufacturing (AM) with two different technologies of an accelerator pedal for the Formula Student 2014 edition to reduce the weight of the original pedal in aluminium and maintain a reasonable level of performance.

Design/methodology/approach

The new and the original accelerator pedals were modelled in a computer-aided design application, and three finite element simulations were performed for each manufacturing technology to evaluate three different driving scenarios. Later on, two physical prototypes were manufactured using two AM technologies: poly-jet and fused deposition modelling (FDM). With these physical prototypes, static tests were carried out to verify the computational simulations and to determine the fracture load, while dynamic tests, based on an input signal from a real racing scenario, were performed to ensure their technical viability.

Findings

Simulations with poly-jet and FDM printing material show that the new design presents a maximum deformation of 4.8 and 4.09 mm, respectively, under a nominal load of 150N. The results of the static tests with the poly-jet physical prototype showed a maximum displacement of 4.05 mm under a nominal load of 150N, while the ultimate load before fracture was 450N. The FDM prototype reached 3.98 mm under 150N and the ultimate load was 350N. Dynamic tests showed that both pedals were able to withstand four Formula Student “Endurance” events without failure.

Originality/value

This paper states that AM approach is a feasible and economically affordable solution in comparison to exiting solutions with metallic alloys and composite materials when designing and manufacturing accelerator pedal arms for Formula Student competition cars. According to these results, the present research argues that, from a technical point of view, the AM pedals stand at a reasonable level of performance in displacements and stresses. This study suggests that AM pedals could be a viable option that must be considered in professional competitive automobiles.

Details

Rapid Prototyping Journal, vol. 22 no. 2
Type: Research Article
ISSN: 1355-2546

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Book part
Publication date: 19 September 2014

Fabio Zambuto, M. V. Shyam Kumar and Jonathan P. O’Brien

We propose that in addition to its resources and capabilities, a firm’s capital structure and financial health will act as an important determinant of its attractiveness…

Abstract

We propose that in addition to its resources and capabilities, a firm’s capital structure and financial health will act as an important determinant of its attractiveness as an alliance partner. Alliances with leveraged firms are prone to unplanned termination due to financial distress, which puts at risk the value embedded in the collaboration. As a result, ceteris paribus, highly leveraged firms will be viewed as less desirable partners in the market for interfirm collaboration when compared to low leverage firms. In support of this proposition, we find that when forming an alliance firms tend to partner with other firms with similar levels of leverage: low-leverage firms partner with other low-leverage firms while high-leverage firms partner with other high-leverage firms, as well as with lower quality ones. Furthermore, we show that alliances with highly leveraged firms are more likely to involve equity participation as a form of ex post protection, especially when they involve partners with relatively lower leverage. Finally, we show that leverage is negatively related to the intensity of alliance activity, suggesting that firms also maintain lower leverage in their capital structure in order to attract potential partners. Overall our results imply that financial policies regarding capital structure have an important role to play in alliancing activity.

Details

Finance and Strategy
Type: Book
ISBN: 978-1-78350-493-0

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Article
Publication date: 1 April 2014

Fariss Terry Mousa and Jaideep Chowdhury

The slack-innovation relationship has interested scholars for years. The authors aim to delve into the impact of financial slack on firm innovation by replicating a…

Abstract

Purpose

The slack-innovation relationship has interested scholars for years. The authors aim to delve into the impact of financial slack on firm innovation by replicating a classic study arguing that this relationship has an inverse U-shape.

Design/methodology/approach

The sample consists of all US firms that were publicly traded between 1993 and 2011. The authors employ the standard econometrics methodology of panel regression with firm-fixed effect and time-fixed effect to estimate the regression equation of firm innovation on financial slack.

Findings

The authors find that the relationship between financial slack and R&D investments is similar to that suggested by earlier authors, thus enhancing the generalizability of this important finding in management research. The authors also find that this relationship holds even during economic downturns.

Originality/value

The authors replicate Nohria and Gulati's classic study by considering the impact of slack on innovation. The authors also move away from survey data, as used by Nohria and Gulati. The authors utilize actual firm-level data for a large sample of US publicly traded firms from 1993 to 2011, thus enhancing the generalizability of these findings.

Details

American Journal of Business, vol. 29 no. 1
Type: Research Article
ISSN: 1935-5181

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Book part
Publication date: 19 September 2014

Johannes M. Drees

Extant research posits that mergers and acquisition (M&As) do not create value. Still many firms adopt expansion strategies such as alliances, joint ventures (JVs), and…

Abstract

Extant research posits that mergers and acquisition (M&As) do not create value. Still many firms adopt expansion strategies such as alliances, joint ventures (JVs), and M&As to grow and enhance their performance. Through performing a meta-analysis on 204 papers that assess the relationship between the three most prevalent expansion strategies formed by firms, alliances, JVs, and M&As and their different substantive and symbolic performance effects, this study contributes in two ways. First, it becomes clear that alliances and M&As enhance a firm’s substantive performance, while no positive performance effect is observed for JVs. In turn, all three expansion strategies boost a firm’s symbolic performance in terms of its legitimacy and status. Second, a distinction between their effects on a firm’s substantive performance in terms of their market-based and accounting-based performance shows that alliances and M&As both positively contribute to a firm’s accounting-based performance, while only the former spurs a firm’s market-based returns. This indicates that M&As have more long-term accounting-based performance effects compared to alliances and JVs, which suggests that in the long-term firms do best by expanding through M&As.

Details

Advances in Mergers and Acquisitions
Type: Book
ISBN: 978-1-78350-970-6

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Article
Publication date: 1 October 2003

Dennis M. Garvis, R. Duane Ireland and Shaker A. Zahra

Increasingly, companies are using alliances and joint ventures to pursue entrepreneurial opportunities. These collaborations are voluntary arrangements between two or more…

Abstract

Increasingly, companies are using alliances and joint ventures to pursue entrepreneurial opportunities. These collaborations are voluntary arrangements between two or more firms that exchange, share, bundle, and create resources in pursuit of entrepreneurial opportunities. This paper proposes that the innovativeness and risk characteristics of these entrepreneurial collaborations significantly influence the outcomes that partner firms realize. Furthermore, interfirm trust works to moderate the effects of these characteristics and allows partners to effectively manage these arrangements. Using data from a sample of alliances and joint ventures engaged in new product development in the telecommunications, medical, and electronics industries, we empirically test the effects of these characteristics on partner satisfaction and partnership success.

Details

Management Research: Journal of the Iberoamerican Academy of Management, vol. 1 no. 3
Type: Research Article
ISSN: 1536-5433

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Book part
Publication date: 27 August 2014

Leonid Bakman and Amalya L. Oliver

The chapter presents a theoretical framework that deals with the basic question of how networks and industries coevolve. We draw upon the structural and relational…

Abstract

The chapter presents a theoretical framework that deals with the basic question of how networks and industries coevolve. We draw upon the structural and relational perspectives of networks to theorize about changes occurring in interfirm networks over time and the coevolutionary linkage of these changes to the industry life cycle. We further extend the widely accepted industry life cycle model by claiming that industry-specific evolutionary patterns impact the structure of the network’s relations, which in turn lead to diversification in the sources of innovation and to variation in the patterns of industrial evolution.

Details

Understanding the Relationship Between Networks and Technology, Creativity and Innovation
Type: Book
ISBN: 978-1-78190-489-3

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Article
Publication date: 11 June 2021

Ahmad Y. Bashir, Noreen Moloney, Musaab E. Elzain, Isabelle Delaunois, Ali Sheikhi, Patrick O'Donnell, Colum P. Dunne, Brendan D. Kelly and Gautam Gulati

This study aims to review international literature systematically to estimate the prevalence of homelessness among incarcerated persons at the time of imprisonment and the…

Abstract

Purpose

This study aims to review international literature systematically to estimate the prevalence of homelessness among incarcerated persons at the time of imprisonment and the time of discharge.

Design/methodology/approach

A systematic review methodology was used to identify quantitative observational studies that looked at the prevalence of homelessness at the time of imprisonment, or up to 30 days prior to that point (initial homelessness), and at the time of discharge from prisons. Studies reported in English from inception to 11 September 2019 were searched for using eight databases (PsycInfo, Medline, Embase, CINAHL, PsycArticles, Scopus, Web of Science and the Campbell Collaboration), in addition to grey literature. Studies were screened independently by three researchers. Results of studies meeting inclusion criteria were meta-analysed using a random effects model to generate pooled prevalence data.

Findings

A total of 18 out of 2,131 studies met the inclusion criteria. All studies originated from the USA, Canada, UK, Ireland or Australia. The estimated prevalence of initial homelessness was 23.41% and at time of discharge was 29.94%. Substantial heterogeneity was observed among studies.

Originality/value

People in prisons are over twenty times more likely to be homeless than those in the general population. This is likely attributable to a range of health and social factors. Studies in this analysis suggest higher rates of homelessness in minority populations and among those with mental illnesses and neurodevelopmental disorders. While there was significant heterogeneity among studies, the results highlight the global burden of this issue and a clear necessity for targeted interventions to address homelessness in this population.

Details

International Journal of Prisoner Health, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1744-9200

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Article
Publication date: 11 March 2004

Tao Gao

This paper delves into the mechanism of the contingency framework for foreign entry mode decisions and identifies two essential tasks that jointly determine the outcome of…

Abstract

This paper delves into the mechanism of the contingency framework for foreign entry mode decisions and identifies two essential tasks that jointly determine the outcome of the entry mode decision. It then recognizes a critical weakness in previous research pertaining to the comparison of entry modes along a key decision criterion, the degree of control. Existing studies generally treat equity involvement as the only source of entrant control, while largely ignoring non‐equity sources of control (i.e., bargaining power and trust). Non‐equity sources of control, when underutilized, amount to missed opportunities, increased resource commitments, and heightened risk exposures in foreign markets. Drawing from a pluralism perspective in transaction and relationship governance, the author presents a more integrative method for the ranking of entry modes along the degree of control. The central message is that companies entering foreign markets should make an earnest effort to identify trust and bargaining power situations and fully utilize their control potential in making entry mode decisions.

Details

Multinational Business Review, vol. 12 no. 1
Type: Research Article
ISSN: 1525-383X

Keywords

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