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Any computing architecture cannot be designed with complete confidentiality. As a result, at any point, it may leak the information. So, it is important to decide leakage threshold in any computing architecture. To prevent leakage more than the predefined threshold, quantitative analysis is helpful. This paper aims to provide a method to quantify information leakage in service-oriented architecture (SOA)-based Web services.

To visualize the dynamic binding of SOA components, first, the orchestration of components is modeled. The modeling helps to information-theoretically quantify information leakage in SOA-based Web services. Then, the paper considers the non-interference policy in a global way to quantify information leakage. It considers not only variables which interfere with security sensitive content but also other architectural parameters to quantify leakage in Web services. To illustrate the attacker’s ability, a strong threat model has been proposed in the paper.

The paper finds that information leakage can be quantified in SOA-based Web services by considering parameters that interfere with security sensitive content and information theory. A hypothetical case study scenario of flight ticket booking Web services has been considered in the present paper in which leakage of 18.89 per cent information is calculated.

The paper shows that it is practically possible to quantify information leakage in SOA-based Web services. While modeling the SOA-based Web services, it will be of help to architects to identify parameters which may cause the leakage of secret contents.

The purpose of this paper is to characterise the effects of mission and performance parameters on the design space of low observable subsonic unmanned combat aerial vehicles (UCAVs) operating in typical Hi-Lo-Hi ground strike missions.

Conceptual design methodologies appropriate to low observable, tailless UCAVs have been integrated into a multidisciplinary aircraft design environment, GENUS, developed at Cranfield University’s aircraft design group. A basic Hi-Lo-Hi mission is designed and a baseline configuration is established through the GENUS framework. Subsequently, an evolutionary optimiser and a robust gradient-based optimiser are used to obtain convergent design solutions for various leading edge sweep angles, mission ranges, cruise Mach numbers and other operational constraints.

The results indicate that performance constraints, specifically in the form of specific excess power (SEP), have a large influence on the overall sizing of subsonic tailless UCAVs. This requirement drives the engine sizing, which represents a considerable proportion of the empty and gross mass of the vehicle. Cruise Mach number studies show that no significant advantages exist for operating at low speeds while maintaining performance requirements consistent with combat missions. There is a drastic increase in the vehicle’s mass and thrust requirements for flight speeds above Mach 0.8, with low sweep configurations showing a more pronounced effect. Increases in the range are not overly dependent on the leading edge sweep angle. Top-level radar cross section (RCS) results also favour configurations with higher leading edge sweep angles, especially from the nose-on aspect. Finally, research and development costs are shown to be directly linked to engine size.

This research shows the use of an integrated aircraft design environment that incorporates aerodynamics, performance, packaging and low observability aspects into the optimisation loop. Through this methodology, this study supports the efforts towards characterising and establishing alternate visions of the future of aerial warfare through the use of low cost, survivable unmanned platforms in network-centric cooperative tasks.

Modern fighter aircraft using active electronically scanned array (AESA) fire control radars are able to detect and track targets at long ranges, in the order of 50 nautical miles or more. Low observable or stealth technology has contested the radar capabilities, reducing detection/tracking ranges roughly to one-third (or even less, for fighter aircraft radar). Hence, infrared search and track (IRST) systems have been reconsidered as an alternative to the radar. This study aims to explore and compare the capabilities and limitations of these two technologies, AESA radars and IRST systems, as well as their synergy through sensor fusion.

The AESA radar range is calculated with the help of the radar equation under certain assumptions, taking into account heat dissipation requirements, using the F-16 fighter as a case study. Concerning the IRST sensor, a new model is proposed for the estimation of the detection range, based on the emitted infrared radiation caused by aerodynamic heating.

The maximum detection range provided by an AESA radar could be restricted because of the increased waste heat which is produced and the relevant constraints concerning the cooling capacity of the carrying aircraft. On the other hand, IRST systems exhibit certain advantages over radars against low observable threats. IRST could be combined with a datalink with the help of data fusion, offering weapons-quality track.

An original approach is provided for the IRST detection range estimation. The AESA/IRST comparison offers valuable insight, while it allows for more efficient planning, at the military acquisition phase, as well as at the tactical level.

Using asymmetric impact–performance analysis for examining an asymmetric relationship between user satisfaction and website features, the present research aims to identify features of high priority for quality improvement. For doing so, the current research was conducted in the context of the E-learning website of the most prestigious university in Iran, namely, the University of Tehran.

The main question was which of the three groups of basic, performance and excitement factors has the required dimensions of the quality of the website based on the model WebQual 4.0 by considering Kano’s user satisfaction model and impact–performance analysis. This is a descriptive survey, applied and cross-sectional study. The study population included Tehran University’s students who enrolled in virtual courses in the academic year 2020–2021 from which a sample of 457 students was selected. The data collection tool was the questionnaire of Webqual 4.0, as well as a researcher-made questionnaire to measure end-user satisfaction.

Using structural equation modeling and multiple regression, the findings showed that the customer’s overall satisfaction with the mentioned website is primarily affected by the feature interaction with services, including the two structures of trust and empathy, and then the dimensions of usability and quality of information. Examining the Webqual 0.4 dimensions indicated that the website usability dimension is a part of the high-performance excitement factors group, the information quality dimension is a part of the high-performance basic factors group and the website interaction dimension is in the low-performance basic factors group.

The research is highly innovative taking the theoretical model of Kano and methodological investigation of asymmetric impact–performance analysis into consideration alongside the WebQual 4.0 as a fundamental model for website assessment. Moreover, the research was conducted on an E-learning website, which is unique and a necessity amid the COVID-19 pandemic.

This paper tests for a positive, a negative and a nonlinear relationship between the share of ownership controlled by firm managers and the management decision to invest in research and development (R&D). Likewise, it examines whether or not institutional investors induce corporate managers with ownership stakes to spend on R&D.

It examines a sample of the United Kingdom (UK) Financial Times Stock Exchange (FTSE) all-shares firms over a longitudinal period from 2009 to 2018. The R&D is measured by the natural logarithm of a firm's R&D spending and a firm's R&D expenditure scaled by its total assets at the end of the year. The results are estimated using the year/industry fixed effects as well as the firm fixed effects.

The results show a positive effect on R&D spending at a lower level of managerial ownership, and a negative impact at a higher managerial ownership level. The findings jointly suggest an inverse U-shaped nonlinear relationship between ownership by firm managers and management decisions on R&D spending. The results also demonstrate that the effect of institutional investors' ownership on R&D spending decisions is observable only at a lower level of managerial ownership and disappears at a higher level.

The results shed the light on the role of managerial ownership in promoting firm innovation. They suggest an optimal level of equity ownership by corporate managers that maximizes R&D spending, implying that firms can effectively manage their R&D spending by restructuring their managerial ownership to maintain an appropriate level of managerial ownership to align managerial interests with shareholder interests by either increasing it to the optimal level or decreasing it when it becomes above this level. The findings also support the limited degree of monitoring and the long-term perspective offered by institutional investors in the UK

The study provides new evidence on the non-monotonic effect of the share of ownership controlled by firm managers on R&D spending decisions. It also expands the growing body of literature and contributes to the debate on the effectiveness of institutional investors in the UK.

Purpose – Research has shown that employers often disfavor racial minorities − particularly African Americans − even when whites and minorities present comparable resumes when applying for jobs. Extant studies have been hard pressed to distinguish between taste-based discrimination where employers' racial animus is the key motivation for their poor treatment of minorities and variants of statistical discrimination where there is no assumption at all of racial animus on the part of the employer. This chapter proposes a test of these theories by observing whether employers use employee referrals as a “cheap” source of information to help assess applicant quality.Methodology/approach – Unique quantitative data encompassing the entire pool of 987 candidates interviewed by one company in the western United States during a 13-month period are used to test our arguments.Findings – We find that employers in this setting are making use of the cheap information available to them: Consistent with statistical discrimination theory, minority referrals are more likely to receive a job offer than non-referred minority applicants, and are not disfavored relative to referred whites.Originality/value of the chapter – Both statistical and taste-based theories of discrimination propose similar observable outcomes (lower rates of disfavored minority hiring). While different mental processes are being invoked by taste-based and statistical discrimination theories, the theories are extremely difficult to distinguish in terms of observable behaviors. Especially for the purpose of designing legal remedies and labor market policies to ameliorate the disparate treatment of minority groups, differentiating between these theories is a high priority.

This chapter examines the evolution of the number of days spent on sick leave following the 2011 reform which halved the maximum sick benefit provided by statutory health insurance in Hungary. This policy change sharply decreased benefits for a large group of high earners, while leaving the incentive to claim sickness benefits unchanged for lower earners, providing us with a “quasi-experimental” setup to identify the incentives effect of sickness benefits. We use a difference-in-differences type methodology to evaluate the short-term effect of the reform. We rely on high-quality administrative data and analyze a sample comprised of prime-age male employees with high earnings and stable employment. Our results show that the number of days spent on sick leave fell substantially for those experiencing the full halving of benefits. Estimating the response of the number of sick days with respect to the fall in potential sickness benefits, we find a significant elasticity of −0.45.

The purpose of this paper is to investigate website quality in rural firms in four countries, by using Gonzalez and Palacios's Web Assessment Index (WAI). There is an assertion in the literature that quality is lower amongst rural firms than urban firms, and lower amongst small firms than large firms. The disadvantages of lack of access to skills and economic peripherality in rural areas are attributed to this. Concurrently, there is reason to surmise that the websites of firms in transition economies may be higher quality than those in market economies. The paper aims to explore websites in distinct rural regions to investigate if variation occurs.

To evaluate website quality the WAI was applied to a sample of 60 rural firms representing 15 each in Scotland, New Zealand, Southern Russia and Hunan Province in China. Analysis of the categorical data was performed using a variety of established methods.

The WAI is of use in terms of website quality management. Additionally, comparisons between the quality of websites in the sample of small rural firms with those of large firms in previous studies support the contention that large firms generally have better quality websites. Results also illustrate that there are some differences in website quality between rural small businesses in the different locations. In particular, small rural firms in Hunan Province in China had websites of observable better quality than those elsewhere. The authors conclude that skills, knowledge and infrastructure have a bearing on the sophistication of small firms' websites.

Implications include that variation in the rural economy by region prevails as the rural economy is not, as often implied, a homogeneous concept.

There are implications in terms of exploring the effects of regulation, culture and infrastructure on rural small to medium-sized enterprises (SMEs). The internet may indeed contribute to rural economies, but only insofar as it is facilitated by infrastructure and access to skills, and by culture and perceived usefulness by business owners.

The paper contributes to the understanding of rural entrepreneurship as a heterogeneous concept by comparing practice in four distinct rural regions. It also adds weight to the emerging identification of exogenous factors as being at least as much a factor in determining the use of ICT in rural SMEs as endogenous motivations, skills and resources.

BTR Material Systems and Courtaulds Aerospace have won a second competitive contract for further development of “multi‐spectral, low‐observable materials and techniques”, following the successful completion of the previous feasibility study of RAM (radar absorbent material) which would also incorporate required IR (infrared) functions.