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This paper aims to present the verification process conducted to assess the functional correctness of the voting system. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) is the most important research institution in Argentina. It depends directly from Argentina’s President but its internal authorities are elected by around 8,000 research across the country. During 2011, the CONICET developed a Web voting system to replace the traditional mail-based process. In 2012 and 2014, CONICET conducted two Web election with no complaints from candidates and voters. Before moving the system into production, CONICET asked the authors to conduct a functional and security assessment of it.

This process is the result of integrating formal, semi-formal and informal verification activities from formal proof to code inspection and model-based testing.

Given the resources and time available, a reasonable level of confidence on the correctness of the application could be transmitted to senior management.

A formal specification of the requirements must be developed.

Formal methods and semi-formal activities are seldom applied to Web applications.

The power and size of five cointegration tests, the ADF‐, Zˆ_α‐, ECM‐, SW‐, and JJ‐statistics, are evaluated in some large‐scale Monte Carlo simulations, when the underlying system is subjected to regime shifts. Following the suggestion by Gregory and Hansen, selects the minimum value for the shift‐corrected statistics evaluated over a set of tentative break points for the regime shifts. The performance of these statistics is compared to the corresponding ordinary statistics in conditions of regime shifts. The results show that no test uniformly outperforms the others in terms of power in the parameter space we have used.

The purpose of this paper was twofold: first, to determine if rotating bending could be used as an effective way of determining the fatigue behaviour of laser-sintered nylon, and second, to examine whether the fatigue behaviour of laser-sintered PA12 showed any significant anisotropy.

Specimens were measured to obtain dimensional accuracy, density and surface roughness levels. Then, uniaxial tensile and rotating-bending fatigue tests were performed. A purpose-built test-jig has been used to subject hourglass-shaped specimens to reversed bending at two frequencies: 50 and 30 Hz. Additionally, thermal and microstructural analyses were performed to understand the underlying mechanisms of failure.

The experiments suggest PA12 specimens will fail in fatigue following the conventional fatigue mechanisms observed in previous research with ductile polymers. Although high-frequency loading caused a heat build-up in the specimen, temperatures stabilised between 20 and 30°C, suggesting that rotating-bending fatigue at frequencies of up to 50 Hz is a valid way of determining the fatigue behaviour of laser-sintered PA12 specimens. Stresses below 20 MPa led to fatigue lives above 1 million cycles. Some anisotropic behaviour was observed in the fatigue test results, with specimens made orientated with the Z axis showing the lowest fatigue lives on average, but an endurance limit of approximately 15 MPa seems to be common for all specimens regardless of their build orientation.

The observed endurance limit of 15 MPa did not depend significantly on the orientation at which a part was built – meaning that it may be possible to guarantee a service life for a part which does not depend on part orientation within a build. Clearly, good-quality control will also be required to ensure performance, but this has important implications for the design of laser-sintered PA12 parts for realistic service conditions.

To our knowledge, this is the first paper to present rotating-bending fatigue data for laser-sintered PA12 parts, and the first to identify an endurance limit which is independent of part orientation.

This paper aims to investigate the effect of post-processing techniques on dimensional accuracy of laser sintering (LS) of Nylon and Alumide^® and fused deposition modelling (FDM) of acrylonitrile butadiene styrene (ABS) materials.

Additive manufacturing (AM) of test pieces using LS of Nylon and Alumide^® powders, as well as the FDM of ABS materials, were first conducted. Next, post-processing of the test pieces involved tumbling, shot peening, hand finishing, spray painting, CNC machining and chemical treatment. Touch probe scanning of the test pieces was undertaken to assess the dimensional deviation, followed by statistical analysis using Chi-square and Z-tests.

The deviation ranges of the original built parts with those being subjected to tumbling, shot peening, hand finishing, spray painting, CNC machining or chemical treatment were found to be different. Despite the rounding of sharp corners and the removal of small protrusions, the dimensional accuracy of relatively wide surfaces of Nylon or Alumide^® test pieces were not significantly affected by the tumbling or shot peening processes. The immersion of ABS test pieces into an acetone bath produced excellent dimensional accuracy.

Only Nylon PA2200 and Alumide^® processed through LS and ABS P400 processed through FDM were investigated. Future work could also examine other materials and using parts produced with other AM processes.

The service bureaus that produce prototypes and end-use functional parts through AM will be able to apply the findings of this investigation.

This research has outlined the differences of post-processing techniques such as tumbling, shot peening, hand finishing, spray painting, CNC machining and chemical treatment. The paper discusses the advantages and disadvantages of each of those methods and suggests that the immersion of ABS test pieces into an acetone bath produced excellent dimensional accuracy.

The purpose of this paper is to test the weak-form efficiency of listed European football stocks in the sample period 2012–2020.

Three powerful tests for randomness are performed, that is, autocorrelation of returns analysis via the Ljung and Box (1978) test, variance ratio test by Lo and MacKinlay (1988) and runs test (Wald and Wolfowitz, 1940).

Results are mixed. Autocorrelation analysis and variance ratio test reject the random walk hypothesis and are, therefore, in line with the findings of Ferreira et al. (2017). In contrast, the runs test only leads to rejection of the random walk hypothesis for five out of 20 football stocks. Interestingly, this applies to shares with the lowest trading volume.

The market for stakes in football clubs can be expected to continue to grow in the future. Thus, the issue whether the price signals derived from listed football clubs are reliable inputs when negotiating the price for a football club stake in a private transaction is of increasing importance.

This study complements, and partly challenges, the results of Ferreira et al. (2017), the only other study in this field, by applying other methods and analyzing a more recent sample period.

The existence of weak‐form efficiency in the equity markets of the three main Central European transition economies (the Czech Republic, Hungary, and Poland) is examined for the period July 1995 through September 2000, using weekly Investable and Comprehensive indexes developed by the International Finance Corporation. Several different approaches are used. Univariate and multivariate tests provide some evidence that stock prices in these exchanges exhibit a random walk, which constitutes evidence for weakform efficiency. This differs in some cases from studies using data for the initial years of these markets. The variance ratio test (VR) of Lo and MacKinlay (1988) yields somewhat mixed results concerning the random‐walk properties of the indexes. A modelcomparison test compares forecasts from a NAÏVE model with ARIMA and GARCH alternatives. Results from the model‐comparison approach are consistent in rejecting the random‐walk hypothesis for the three Central European equity markets.

The adoption of the ISO 9001 Quality Management Systems Standard has proven to be a persistent and growing phenomenon in services and manufacturing, yet to date little research has been done that can indicate how far improved business performance can be attributed to it rather than counter‐intuitive causes. The paper aims to examine the evidence for the causal links between quality management system certification and improved performance in the empirical literature.

A method is proposed for testing how far performance improvement can be attributed to quality management system certification and how far attribution to other causes applies. This method is illustrated on a longitudinal study and then utilised to interpret the findings of other longitudinal studies.

It is concluded that although there is some evidence to indicate that quality management system certification has some causal influence on business performance, there is also evidence for the existence of a substantial mechanism whereby better performing firms self‐select to adopt certification. Possible causes for this mechanism are discussed.

The existence of a self‐select mechanism has profound implications for interpreting business performance achievements associated with quality management system certification because the benefits found may well be inflated by its presence. The authors suggest that richer theory is needed that can incorporate bi‐directional influences and new research is needed to explore the underlying causes of adoption selection effects.

The paper provides researchers with a method for testing and discussing causation influences on results. It provides evidence that a substantial part of the association found in the research on quality management system certification and business benefits may be due to counterintuitive causes.

This paper investigates how individuals determine their tax morale levels and tax compliance decisions. Using a questionnaire survey and a multivariate tests procedure, the paper revealed that tax evasion is morally acceptable in Jordan under some circumstances, indeed there could be an affirmative duty to evade taxes since the government is perceived to be highly corrupted. The findings also show that while the extent of the governmental corruption has a positive (negative) effect on tax non-compliance (tax morale), the efficient expenditure of governmental tax revenues has a negative (positive) impact on tax non-compliance (tax morale). The individuals’ tax non-compliance decisions are likewise positively affected by the tax rates and by the taxation system’s being perceived as unjust, but decline with the increase of audit rates and the subsequent penalty rates. The degree and effectiveness of these determinants are dependent on the individual’s level of risk aversion, financial constraints and the surrounding referent groups. The results also confirm that individual factors play a significant role in determining the level of tax morale. Overall, the tax morale level and the compliance decision of an individual are greatly influenced by gender, age, educational level, occupational status and religious background.

With computer technology fast becoming the engine that drives productivity, IT systems have become more pervasive in the daily operations of many businesses. Large, as well as small, businesses in the USA now rely heavily on IT systems to function effectively and efficiently. However, past studies have shown CEOs do not always understand how reliant their business is on IT systems. To the authors’ knowledge, no research has not yet examined if financial markets understand how IT affects the performance of businesses. The paper aims to discuss these issues.

In this study, the authors utilize the event study method to examine how financial markets interpret weaknesses in businesses IT systems. The authors examine this in the context of the Sarbanes-Oxley Act – Section 404 requirements and utilize the internal reporting requirement in the annual financial statement filing with the Securities Exchange Commission as a proxy to evaluate how the financial markets interpret IT weaknesses.

Using an event study, the authors show that the market does not necessarily understand and respond to the effects of IT weaknesses on overall financial performance of firms and thus challenge the efficient market hypothesis theory.

A second contribution is methodological in nature. IS researchers thus far have been using limited market benchmarks, statistical tests, and event windows in their respective event studies of market performance. This study shows shortcomings of that approach and the necessity of expanding usage of available event analysis tools. The authors show that using more than one market benchmark and statistical test across multiple time frames uncovers the effects that using a single benchmark and test over a single window would have overlooked.