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Smart contracts are written in high-level programming languages, compiled into Ethereum Virtual Machine (EVM) bytecode, deployed onto blockchain systems and called with the corresponding address by transactions. The deployed smart contracts are immutable, even if there are bugs or vulnerabilities. Therefore, it is critical to verify smart contracts before deployment. This paper aims to help developers effectively and efficiently locate potential defects in smart contracts.

GethReplayer, a smart contract testing method based on transaction replay, is proposed. It constructs a parallel transaction execution environment with two virtual machines to compare the execution results. It uses the real existing transaction data on Ethereum and the source code of the tested smart contacts as inputs, conditionally substitutes the bytecode of the tested smart contract input into the testing EVM, and then monitors the environmental information to check the correctness of the contract.

Experiments verified that the proposed method is effective in smart contract testing. Virtual environmental information has a significant effect on the success of transaction replay, which is the basis for the performance of the method. The efficiency of error locating was approximately 14 times faster with the proposed method than without. In addition, the proposed method supports gas consumption analysis.

This paper addresses the difficulty that developers encounter in testing smart contracts before deployment and focuses on helping develop smart contracts with as few defects as possible. GethReplayer is expected to be an alternative solution for smart contract testing and provide inspiration for further research.

This paper discussed quantifying architect, engineer and contractor (AEC) professionals' cross-work culture productivity by comparing between Malaysian and United Kingdom (UK) projects during industrialized building project delivery. This study addressed the second part of a mixed method research design study.

This study hypothesized that with understanding of cultural work knowledge between professionals during design phase coupled with competent technological support, productivity can be improved. It utilized Cognitive Organizational Theory (COT) protocols to test conceptual models in SimVision®. Organizational structure, project intensity, and statistical validations parameters were performed to obtain the reliability and generalization of the result.

This study found that with Building Information Modeling (BIM) technology intervention, the handling of exception, coordination and decision-making time could be improved, resulting in better project performances. The result also indicated that in choosing organizational fit, national culture factor needed to be considered; otherwise, organizational change would be unacceptable. By changing the operational process from intensive to reciprocal task intensity with BIM technology intervention, the effect on productivity would be similar to changing hierarchical organizational structure to flatter organizational structure.

Project discrepancies issues are limitedly discussed due to companies' confidentiality. The paper only focuses on understanding the effects of human factors during the integrated project delivery phase.

The findings could support developing countries' professionals to collaborate effectively with developed countries' professionals.

The development of the project's cultural knowledge experimentations will provide guidance to teams involved in international projects from developed and developing countries in pursuing joint ventures in project deliveries in either country successfully.

The role of construction industry in harnessing human and material resources of a nation cannot be overemphasised; hence, the emergence of the requirement of leadership. This study aims to assess the usage of factors of transactional leadership style (TSLS) by the project managers (PMs) in the Nigeria construction industry.

A survey research design approach with questionnaire as an instrument of gathering data was adopted. Out of 1,233 questionnaires distributed, data from 975 received with acceptable feedback were analysed using both descriptive and inferential statistics.

This study revealed the following factors under active management by exception as the TSLS factors often employed by PMs in Nigeria. These factors are the three frequently used factors: they are: “always give clear and final instructions to be implemented in the project”; “always observed the progress of the project, assessed risk and took precaution to avoid mistakes in the project”; and “always closely monitor performance for errors needing correction”. This study concludes that it is imperative for PMs in the study area to adopt and incorporate these factors to ensure continuous successful delivery of construction projects.

Therefore, it is hoped that the findings of this research will help the construction industry managers to address the age-long but unrecognised leadership problem confronting the sector, thereby boosting project delivery.

The findings establish the appropriateness or otherwise of adoption of factors of transactional leadership, either in part or a whole.

Given the importance of teacher leadership in influencing, motivating and inspiring student learning engagement and associated learning outcomes, a robust instrument to assess this construct is critical. Although there are some teacher leadership instruments available in existing literature, efforts to adapt robust psychometric instruments to measure teachers' leadership practices in Ethiopian higher education institutions have been limited. Therefore, this study attempted to address this gap by adapting the Teacher Leadership Scale (TLS) based on the Multifactor Leadership Questionnaire (MLQ-5X) and validating its psychometric properties for use in higher education settings.

Using a cross-sectional design, the study involved 409 undergraduate university students who were randomly selected from public universities. Factor analytic methodologies, including exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), were used to analyze the data collected.

The result confirmed a set of 36 items arranged in nine factors, which have a theoretically supported factor structure, excellent model fit and robust evidence for validity, and reliability and measurement invariance. These results demonstrate that the scale is a strong psychometric tool for measuring the leadership profile and practice of higher education teachers.

It can be concluded that the TLS can assist stakeholders in several ways. Researchers can benefit from the scale to measure teachers' leadership practices and predict their influence on student learning outcomes. In addition, the scale can help practitioners and policymakers collect relevant data to rethink teacher professional development initiatives, leadership training programs and other practices aimed at improving teacher leadership effectiveness.

The purpose of this paper is to describe the mediating effects of transformational and transactional leadership styles on the relationship between organizational ethics and workplace incivility.

The study employed cross-sectional survey design. Data were obtained from 209 employees from the telecommunication sector. The structural equation model was employed as the analytical tool to test the hypotheses of the study.

Organizational ethics was negatively related to workplace incivility. Both transformational and transactional leadership styles mediated the relationship between organizational ethics and workplace incivility.

Human resource developers and managers can employ, appraise, train and develop managers who can ethically demonstrate transactional, and transformational leadership behaviors to deal with workplace incivilities.

The paper makes an important contribution to the existing organizational literature by establishing the relevance of transformational and transactional leadership styles as mediators of the nexus between organizational ethics and workplace incivility in the telecommunication sector.

This study investigated the asymmetric effects of changes in policy uncertainty on real sector variables in Brazil, China, India and South Africa.

The study used the nonlinear autoregressive distributed lag (NARDL) modeling framework.

The results showed that both in the long run and short run, rising uncertainty not only increases consumer prices significantly in these economies, but also impedes aggregate and sectoral output growths, and deters investment, employment and private consumption. Contrary to economic expectation, the results also showed that in the long run, declining uncertainty impedes aggregate and sectoral output growths in these economies, and significantly hinders employment in South Africa and Brazil. This suggests that in the long run, economic agents in these economies somewhat behave as if uncertainty is rising. The authors also found significant asymmetric effects in the response of real sector variables to uncertainty both in the long run and short run, which justifies the choice of NARDL framework for this study.

The sample is limited to Brazil, India, China and South Africa. While Brazil, India and China are three of the most prominent large emerging market economies, South Africa is the largest emerging market economy in Africa.

To lessen the adverse effects of policy uncertainty observed in the results, there is need for sound institutions and policy regimes that can promote predictable policy responses in these economies so that policy neither serves as a source of uncertainty nor as a channel through which the effects of other shocks are transmitted.

Apart from using the NARDL framework to capture the asymmetric effects of policy uncertainty, this study also accounted for the sectoral effects of uncertainty in emerging markets.

The current study’s goal is to investigate how lean, agile, resilient and sustainable human resource management (LARS HRM) affects green innovation and environmental performance, both directly and indirectly.

Partial least squares-structural equation modeling (PLS-SEM) was used to analyze the data based on a sample of 273 Tunisian businesses in the industrial and service sectors that were certified ISO 9001.

With the exception of AHRM–GPdtI, the results show that the mainstream advanced theory on direct effects was verified. With regard to indirect effects, everything of the literature that was presented was accepted, with the exception of the relationship between AHRM–GPdtI–EP, AHRM–GPssI–EP and RHRM–GPdtI–EP.

This research is distinctive in that it aims to incorporate every LARGS paradigm within the HRM field. By taking green innovation into consideration, it closes the current gaps on the direct and indirect effects of LARS HRM on environmental performance. Our study is unique in that it incorporates large, industry-operating, certified ISO 9001 firms with those in the service sector, with the goal of achieving greater generalization of results.

This study aims to examine the factors of the vegan lifestyle on the travel experience. Special emphasis was placed on difficulties during travel and influencing factors for destination choice.

The vegan lifestyle has emerged as a growing market. The dietary reference is well-known, but the impact of the vegan lifestyle on tourism has received less attention. Earlier researchers have cited motivations of ethics, the environment and health as key. An online survey was conducted within the target group of vegans to provide more understanding of vegan tourism.

A few participants stated that they refused to visit countries due to too high meat consumption or due to long flight distances. Nature was named as the most decisive factor for choosing a travel destination among the respondents. Problems that might arise were mainly the general lack of awareness about veganism, as well as the confusion between vegetarianism and veganism in the destinations. Most respondents indicated that these problems were generally prepared for during the pre-planning process.

Research on vegan tourism is a relatively unexplored niche topic, the study used related topics adapted to a vegan tourism context.

Enhanced education about veganism among tourism service providers would be desirable to counteract such problems in the future and make the travel experience more carefree for vegans.

There has been little research in the field of vegan tourism, thus, this study provides valuable information on the needs and challenges of this growing market.

The purpose of this research is to identify and investigate some natural dyes with halochromic properties for potential use as food spoilage indicators to reduce waste and curve the negative effects of food borne diseases.

Exactly 10 potential dye-yielding plants were selected based on their colour (mostly purple, red, maroon and pink). Solvent extraction was used to extract the dyes and pH differential method was used to determine the concentrations of anthocyanin in the extracted dyes. Different concentrations of hydrochloric acid and sodium hydroxide (0.1 M, 1 M and 2 M) in drops and in excess as acidic and basic solution, respectively, were used to test the halochromicity of the extracted dyes. Methyl red (a synthetic dye) was used as a reference standard/control. The pH of the dyes was recorded before and after addition of both NaOH and HCl solutions.

Five out of the 10 dyes extracted (labelled as dye A–E for Ti plant (green Cordyline fruticosa), coleus (Coleus blumei), paper flower (Bougainvillea glabra), painted nettle (Palisandra coleus) and purple heart (Setcresea purpurea), respectively, were found to be halochromic (even at low doses) by changing its colour when exposed to both acidic and basic solutions. While other dyes labelled F–J for red acalypha (Acalypha wilkesiana), golden shower (Cassia fistula), golden dew drop (Duranta repens), wild sage (Lantana camara var Aculeata) and pink oleander (Apocynaceae Nerium oleander), respectively, were either completely insensitive to the solutions in drops, slightly sensitive at high doses or the colour change is insignificant. Although some dyes were found to be more sensitive than others but in most cases, the colour changes in halochromic dyes were more stable in acidic conditions than in basic making it more sensitive to the basic than the acidic solution with the exception of dye A and E (to some extent) which was sensitive to both acidic and basic solution. The anthocyanin contents of dye A–J were found to be between the range of 2.28–10.35 mg/l with dye E having the lowest and dye J with the highest anthocyanin concentration, respectively. The initial pH of all the dyes falls within the range of 4.8–7.3 with most found within the acidic range.

Halochromic dye research studies are still at the infancy stage in developing world despite the vast available and abundant potential natural halochromic dye-yielding plants. The study explored this area of research and gives an opportunity for the development of smart packaging for pH-sensitive foods using natural dyes as an alternative to conventional synthetic dyes to reduce cost and also curve the negative effect of synthetic dyes as well as food borne diseases.

In this vein, this paper aims to provide empirical evidence on the following questions: Which expansion strategies offer better operational and economic performance? What effects does performance-related diversification have? How do other factors such as size, quality, service offered, location or seasonality interact with performance.

In this paper, the analysis of the effects of growth strategies and hotel attributes on performance is carried out with a sample of 255 hotels that operate internationally. Using panel data and quantile regression, this study evaluates the effect of expansion and diversification on the hotels’ performance.

From these findings, it appears that the equity strategy (own hotels) outperforms non-equity strategies (hotels under rental, franchise and management contract) at the operational level. However, the economic return of the property, both adjusted and unadjusted to risk, is lower under the property ownership strategy than under the franchise and management strategies because, in general, it requires a higher investment. Regarding diversification, the growth strategy based on related diversification in food and beverage services has a negative impact on performance, calling into question the synergies between the two businesses. However, an exception to this effect is seen among those hotels, mainly those in the Caribbean, that opt to provide all-inclusive services, since these hotels achieve better occupancy rates and more stable results.

This study has not taken into account the effect of hotel property revaluation on the performance of the ownership strategy, as there is no information on the historical average revaluation at the level of each individual hotel. This study has also been unable to include information regarding the level of competition and seasonality of sales.

This paper considers a wide number of factors that can influence the performance of hotels. Second, this is the only paper that studies the impact of growth strategies from the point of view of the hotel chain. Also, the sample considered uses data at the individual level on hotels and this research analyses not only operational performance but also economic performance.