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Simulation is a well-known technique for using computers to imitate or simulate the operations of various kinds of real-world facilities or processes. The facility or process of interest is usually called a system, and to study it scientifically, we often have to make a set of assumptions about how it works. These assumptions, which usually take the form of mathematical or logical relationships, constitute a model that is used to gain some understanding of how the corresponding system behaves, and the quality of these understandings essentially depends on the credibility of given assumptions or models, known as VV&A (verification, validation and accreditation). The main purpose of this paper is to present an in-depth theoretical review and analysis for the application of VV&A in large-scale simulations.

After summarizing the VV&A of related research studies, the standards, frameworks, techniques, methods and tools have been discussed according to the characteristics of large-scale simulations (such as crowd network simulations).

The contributions of this paper will be useful for both academics and practitioners for formulating VV&A in large-scale simulations (such as crowd network simulations).

This paper will help researchers to provide support of a recommendation for formulating VV&A in large-scale simulations (such as crowd network simulations).

This study proposes a Bayesian approach to analyze structural breaks and examines whether structural changes have occurred, at the onset of civil war, with respect to economic development and population during the period from 1945 to 1999.

In the Bayesian logit regression changepoint model, parameters of covariates are allowed to shift individually, regime transitions can move back and forth, and the model is applicable to cross-sectional, time-series data.

Contrary to popular belief that the causal process of civil war changed with the end of the Cold War, the empirical analysis shows that the regression relationships between civil war and economic development, as well as between civil war and population, remain quite stable during the study period.

This is the first to develop a Bayesian logit regression changepoint model and to apply it to studies of economic development and civil war.

The current study seeks to examine the impact of web marketing (through the company's website) on corporate social responsibility (CSR) and firms' performance across companies listed in the Muscat Stock Exchange (MSX), Oman.

This research analyses qualitative and exploratory data taken from companies' website, annual reports (the financial year 2019), Google search and CSR report from 69 out of total 117 listed companies in the MSX to analyze the impact of web marketing on CSR and firms' performance proxied by return of assets (ROA), return of equity (ROE) and Tobin's Q (TQ).

Web marketing on CSR positively affects firms' performance. Especially, the positive effect of web marketing on firms' performance is stronger for listed companies. Web marketing enhances financial performance proxied by ROA, ROE and TQ.

The research findings provide new insights that are able to enlighten governing bodies in Oman to make standardized compulsory CSR spending (say, 0.5% on profit after tax) by listed companies in MSX.

This research presents evidence that web marketing on CSR can increase firms' performance and brand image among stakeholders. This is the first study to examine the impact of web marketing on CSR and firms' performance using empirical data in Oman.

The purpose of this study is to verify how the carbon doping of the WC-Co cemented carbide (CC) affected their structure before their processing by hot isostatic pressing (HIP) technology.

The samples for this experiment were fabricated by selective laser melting technology (SLM) using a YAG fiber laser with a power of P = 40 W and a scanning speed of 83 mm/s. The subsequent carbon doping process was performed in a chamber furnace at 900 0 C for 1, 4 and 12 h. The HIP was performed at 1,390°C and pressures of 40 MPa, 80 MPa and 120 MPa. The changes induced in the structures were evaluated using X-ray diffraction and various microscopic methods.

X-ray diffraction analysis showed that the structure of the samples after SLM consisted of WC, W₂C, Co₄W₂C and Co phases. As a result of the increase in the carbon content in the structure of the samples, the transition carbide W₂C and structural phase Co₄W₂C decayed. Their decay was manifested by the coarsening of the minor alpha phase (WC), which occurred both during the carburizing process and during the subsequent processing using HIP. In the samples in which the structure was carburized prior to HIP, only the structural phases WC and Co were observed in most cases.

The results confirm that it is possible to increase the homogeneity of the CC structure and thus its applicability in practice by additional carburization of the sample structure with subsequent processing by HIP technology.

Occupational Safety and Health Administration (OSHA) of the U.S. government ensures that all health and safety regulations, protecting the workers, are enforced. OSHA officers conduct inspections and assess fines for non-compliance and regulatory violations. Literature discussion on the economic impact of OSHA inspections with COVID-19 related citations for the construction sector is lacking. This study aims to investigate the relationships between the number of COVID-19 cases, construction employment and OSHA citations and it further evaluates the total and monthly predicted cost impact of OSHA citations associated with COVID-19 violations.

An application of multiple regression analysis, a supervised machine learning linear regression model, based on K-fold cross validation sampling and a probabilistic risk-based cost estimate Monte Carlo simulation were utilized to evaluate the data. The data were collected from numerous websites including OSHA, Centers for Disease Control and the World Health Organization.

The results show that as the monthly construction employment increased, there was a decrease in OSHA citations. Conversely, the cost impact of OSHA citations had a positive relationship with the number of COVID-19 cases. In addition, the monthly cost impact of OSHA COVID-19 related citations along with the total cost impact of citations were predicted and analyzed.

The application of the two models on cost analysis provides a thorough comparison of predicted and overall cost impact, which can assist the contractors to better understand the possible cost ramifications. Based on the findings, it is suggested that the contractors include contingency fees within their contracts, hire safety managers to implement specific safety protocols related to COVID-19 and request a safety action plan when qualifying their subcontractors to avoid potential fines and citations.

The purpose of this study is observing the disclosure pattern of integrated reporting (IR) and investigating its relationship with a firm's operational, financial and market growth performance measured in the form of return on assets (ROA), return on equity (ROE) and market-to-book value ratio respectively in the voluntary disclosure regime of Bangladesh.

This research is quantitative, based on a pooled-OLS regression analysis of 20 firms listed under ten different nonfinancial industries of the Dhaka Stock Exchange (DSE) for three financial years from 2015–2016 to 2017–2018, with 60 firm-year observations. A manual content analysis based on a structured integrated reporting disclosure index (IRDIN) measures the extent of disclosure in the corporate annual reports. The practical model consists of the dependent variable IRDIN and the independent variables ROA, ROE and market-to-book value ratio. The natural logarithm of total assets and financial leverage are the two controlling variables used in the model.

The findings deduced from the empirical results indicate that the IRDIN is positively and significantly related to all three performance variables. Content analysis shows an increasing pattern of disclosure of the constructed index elements by the sample firms.

A Small sample size may deter the generalization of the research findings in other voluntary disclosure regimes. Self-constructed IRDIN index scores may be affected by subjective judgment while assessing the annual reports.

Capital market regulators can gain valuable insights regarding the suitability of implementing IR in Bangladesh as the results show a positive relationship of firm performance with the adoption of this revolutionary paradigm in corporate reporting.

This study adds value to the existing limited literature of IR disclosure and firm performance in Bangladesh by incorporating content analysis and regression analysis to understand how firms respond to the demand of value creation by the stakeholders in a voluntary disclosure regime. This study captures sample firms from all the nonfinancial industries of Bangladesh with a unique IR index, which is the first of its kind.

The purpose of this study is to analyse and discuss K-12 mathematics and technology teachers' perceptions on integrating programming in their teaching and learning activities, and perceptions on different programming tools.

The approach of a case study was used, with data collected from three instances of a professional development programming course for K-12 teachers in mathematics and technology.

The findings show that there are perceived challenges and opportunities with learning and integrating programming, and with different programming tools. Many teachers perceive programming as fun, but lack the time to learn and implement it, and view different programming tools as both complementary to each other and with individual opportunities and challenges.

The practical implication of the research is that it can provide guidance for teachers and other stakeholders that are in the process of integrating programming in K-12 education. Further, the research provides useful information on teachers' experiences on working with different programming tools.

The social implication of the research is that the overall aim of the nation-wide integration process might not succeed if the challenges identified in this study are not addressed, which could have negative effects on the development of students' digital competence.

The value of the research is that it identifies important challenges and opportunities for the integration of programming. That is, that many teachers perceive the different programming tools available as complimentary to each other, but are hesitating about what is expected of the integration. Findings could also be valuable for future course design of the teacher professional development.

The purpose of this paper is to investigate how public/private hybrid and ambiguous organizations played pivotal roles in a governmental programme of housing reconstruction following a major earthquake in central Italy in 2009. Venturing beyond the boundaries of institutional isomorphism and using a Foucauldian approach, the longitudinal analysis seeks to illuminate accounting and performance challenges and provide insights to the calculative techniques associated with evacuee housing.

In “act 1” this paper investigates the role of a consortium created during the recovery stage of the disaster to construct temporary housing. In “act 2” attention shifts to consortia established for the reconstruction of buildings in devastated communities. The total observation period is 11 years. 31 semi-structured interviews were conducted with 15 key-actors. A broad range of official documents was also consulted.

In the immediate aftermath of the earthquake a comprehensive reporting system was established to facilitate the construction of 19 new towns for 15,000 evacuees. The mix of accountants, engineers and architects who developed the system and a building prototype evidences the assembly of diverse calculative techniques by different experts and the de-territorialization of subject disciplines. During reconstruction technologies of government included the introduction of standardised systems and vocabularies that homogenised administrative procedures among diverse experts.

This paper provides academics and policymakers with insights to accounting, performance management and accountability in hybrid organizations in the largely unexplored realm of post-disaster evacuee housing. Further studies are needed to examine the politics of calculation in similar contexts.

This paper fills a gap in the literature by exploring the role played by individual experts working for hybrid organizations. Further, by exploring actual practices over an extended period of post-disaster recovery and reconstruction, the study highlights how experts intervened to solve problems at the meso-political level and at the micro-organizational level.

The purpose of this paper is to evaluate the influence of culture in terms of individualism and collectivism (I-C), store image and customer satisfaction, on purchase intention at supermarkets.

In order to carry out the descriptive and quantitative research, the authors applied 443 questionnaires to consumers in two Brazilian supermarket chains. The authors used structured equation modeling for data analysis.

Customers’ satisfaction and the evaluation of store image positively affect purchase intention; however, I-C did not show any effect. The cultural dimension slightly influenced the assessment of store image by only 2 percent. Store image positively affects consumer satisfaction.

This study used convenience sampling and omission of vertical and horizontal variations of I-C in data analyses. The authors suggested the use of probabilistic sampling and the inclusion of vertical and horizontal variations of I-C. The relationships investigated herein can still be analyzed in other contexts.

In order to increase satisfaction and purchase intention, it is necessary to prioritize aspects related to layout, service and products’ variety and quality. Still, managers should not worry about I-C, since it does not affect purchase intention.

The authors observed the relevance of the study after carrying out a literature review on the subject. There is a lack of studies that investigate the relationship between I-C, evaluation of store image, consumer satisfaction and purchase intention, either together or in the context of supermarkets.

Within critical-infrastructure industries, bow-tie analysis is an established way of eliciting requirements for safety and reliability concerns. Because of the ever-increasing digitalisation and coupling between the cyber and physical world, security has become an additional concern in these industries. The purpose of this paper is to evaluate how well bow-tie analysis performs in the context of security, and the study’s hypothesis is that the bow-tie notation has a suitable expressiveness for security and safety.

This study uses a formal, controlled quasi-experiment on two sample populations – security experts and security graduate students – working on the same case. As a basis for comparison, the authors used a similar experiment with misuse case analysis, a well-known technique for graphical security modelling.

The results show that the collective group of graduate students, inexperienced in security modelling, perform similarly as security experts in a well-defined scope and familiar target system/situation. The students showed great creativity, covering most of the same threats and consequences as the experts identified and discovering additional ones. One notable difference was that these naïve professionals tend to focus on preventive barriers, leading to requirements for risk mitigation or avoidance, while experienced professionals seem to balance this more with reactive barriers and requirements for incident management.

Our results are useful in areas where we need to evaluate safety and security concerns together, especially for domains that have experience in health, safety and environmental hazards, but now need to expand this with cybersecurity as well.