Mobile ad hoc networks rely on cooperation to perform essential network mechanisms such as routing. Therefore, network performance depends to a great extent on giving participating nodes an incentive for cooperation. The level of trust among nodes is the most frequently used parameter for promoting cooperation in distributed systems. There are different models for representing trust, each of which is suited to a particular context and leads to different procedures for computing and propagating trust. The goal of this study is to analyze the most representative approaches for mobile ad hoc networks. It aims to obtain a qualitative comparison of the modeling approaches, according to the three basic components of a trust model: information gathering, information scoring and ranking, and action execution.
The paper identifies the different tasks required by a trust system and compares the way they are implemented when the system model itself is based on information theory, social networks, cluster concept, graph theory and game theory. It also provides a common nomenclature for the models. The study concentrates exclusively on the trust models themselves, without taking into account other aspects of the original articles that are beyond the scope of this analysis.
The study identifies the main components that a trust model must provide, and compares the way they are implemented. It finds that the lack of unity in the different proposed approaches makes it difficult to conduct an objective comparison. Finally, it also notices that most of the models do not properly manage node reintegration.
The best of our knowledge, the study is the first that uses information scoring and ranking as classification key. According to this key, approaches can be classified as based on information theory, clusters and social network theory, and cooperative and non‐cooperative game theory. It also provides a common nomenclature for all of them. Finally, the main contribution of the paper is to provide an analysis of the most representative approaches and present a novel qualitative comparison.
The contribution of the present case lies in the critical view that every business actor should exercise – be it general manager, middle management, supervisor or…
The contribution of the present case lies in the critical view that every business actor should exercise – be it general manager, middle management, supervisor or executive – when building a strong organizational culture in corrupt political environments.
The purpose of this case study is to explore the dilemma in which Marcelo Odebrecht, once CEO of Odebrecht, found/determined whether to continue with the business model established by the founders of Odebrecht or take a new path for the organization. After exploring the corrupt acts of Odebrecht and the scope of Operation Lava Jato, the reader can reflect on the importance of organizational culture (according to the three levels proposed by Schein) in the face of the emergence of corruption. By generating discussions about organizational culture, business ethics, political culture and corruption, the organizational culture of Odebrecht is problematized in relation to its real behavior.
Complexity academic level
Students of administration, business and international business undergraduates and graduates, as well as members of senior management in companies in the infrastructure sector. Also, given the plurality of possible readings, it is recommended that the case also be used in courses or specializations in organizational psychology, organizational sociology or organizational anthropology.
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CSS 5: International Business.
The risks of highly presidential and personalist systems.
The main significance of the summit series has been to give a reading of US relations with Latin America. As such, US President Donald Trump’s last-minute decision to…
The purpose of this paper is to provide a selected bibliography of recent resources on library instruction and information literacy.
The paper identifies and annotates periodical articles, monographs, and audiovisual material, in the area of library instruction and information literacy.
The paper provides information about each source, discusses the characteristics of current scholarship, and describes sources that contain unique scholarly contributions and quality reproductions.
The information in the paper may be used by librarians and interested parties as a quick reference to literature on library instruction and information literacy.
The purpose of this paper is to analyse the gender wage differential at different points of the wage distribution. It investigates the existence of glass ceilings and…
The purpose of this paper is to analyse the gender wage differential at different points of the wage distribution. It investigates the existence of glass ceilings and sticky floors in the Mauritian labour market. There is no previous empirical work studying gender inequality in the labour market for the small island economy of Mauritius.
To investigate whether wage differentials are higher at the top or bottom ends of the wage distribution, the authors examine the wage disparities across different quantiles of the wage distribution. The gender wage disparities are assessed using quantile regression and decomposition techniques at the 10th, 25th, 50th, 75th and 90th quantiles. Survey data from the Continuous Multi-Purpose Household Survey from 2006 to 2013 is used.
The results reveal that sticky floors are more pronounced than glass ceilings over the years. Further, for the years 2008, 2010 and 2012, it is noted that at the 75th quantiles, the gender wage differentials started to rise showing glass ceiling effects. The combination of both sticky floors and glass ceilings are characterised by the unexplained factors providing evidence for gender discrimination in the Mauritian labour market.
This is the first study analysing the glass ceilings or sticky floors in the Mauritian labour market. Though the research is limited to Mauritius, the latter being a small island economy can serve as a case study for other island economies and also for the African continent.
Previous research studies have testified that safety culture positively affects safety performance. However, the progression by which safety culture affects safety…
Previous research studies have testified that safety culture positively affects safety performance. However, the progression by which safety culture affects safety performance has not yet been examined. Also, how safety culture affects the overall safety performance at different levels of the organization is yet to be explored. In order to address this issue, the purpose of this paper is to study the effect of multilevel safety culture upon safety performance over time.
A conceptual causal-loop diagram is constructed using the group model building approach to establish the relationship between safety culture components (e.g. psychological, behavioral and situational) and the factors associated with safety performance (e.g. risk level, safety behavior, unsafe conditions, unsafe acts and incident rate). Considering the dynamic nature and intricacy of the safety management system, the system dynamics approach has been employed to develop the model.
The results indicate that the safety culture at the tactical level (middle management) and operational level is much more effective than strategic level (top management) in ameliorating the safety performance of the organization.
The scope of this study is limited to the effect of multilevel safety culture on safety performance. The focus is on the dynamics of personal, behavioral and situational factors of top management, middle management and workers to reinforce the safety performance of the organization. Future research can be protracted to build other models of safety.
First and foremost, the findings summarized in this paper can be implemented by organizations to achieve the total safety culture to upgrade safety performance.
This paper presents the holistic view of multilevel safety culture in an organization’s hierarchy. It shows how multilevel level safety culture in an organization interacts with the safety management system to enhance the safety performance of the organization.