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In this paper, we consider a two color multi-drawing urn model. At each discrete time step, we draw uniformly at random a sample of m balls (m≥1) and note their color, they will be returned to the urn together with a random number of balls depending on the sample’s composition. The replacement rule is a 2 × 2 matrix depending on bounded discrete positive random variables. Using a stochastic approximation algorithm and martingales methods, we investigate the asymptotic behavior of the urn after many draws.

The purpose of this paper is to develop an original model and a solution procedure for solving jointly three main strategic fleet management problems (fleet composition, replacement and make-or-buy), taking into account interdependencies between them.

The three main strategic fleet management problems were analyzed in detail to identify interdependencies between them, mathematically modeled in terms of integer nonlinear programing (INLP) and solved using evolutionary based method of a solver compatible with a spreadsheet.

There are no optimization methods combining the analyzed problems, but it is possible to mathematically model them jointly and solve together using a solver compatible with a spreadsheet obtaining a solution/fleet management strategy answering the questions: Keep currently exploited vehicles in a fleet or remove them? If keep, how often to replace them? If remove then when? How many perspective/new vehicles, of what types, brand new or used ones and when should be put into a fleet? The relatively large scale instance of problem (50 vehicles) was solved based on a real-life data. The obtained results occurred to be better/cheaper by 10% than the two reference solutions – random and do-nothing ones.

The methodology of developing optimal fleet management strategy by solving jointly three main strategic fleet management problems is proposed allowing for the reduction of the fleet exploitation costs by adjusting fleet size, types of exploited vehicles and their exploitation periods.

The purpose of this paper is to debate on how to achieve, in countries that have invested in the North American model of the regulatory state, the greatest efficiency in creating norms for the organization of public and private activities in order to guarantee the autonomy and technical impartiality required for the proper functioning of regulatory agencies.

This paper describes the development of the legal framework regarding regulatory agencies in Brazil. The research was based on bibliographical data, media reports, and the Brazilian Supreme Court decisions.

The regulation dissemination through regulatory agencies in Brazil has given rise to a series of controversies concerning the limits of their performance and the extent of their technical discretion. According to the findings, it is concluded that these independent agencies should be guided by the following four pillars: (1) the legal rule of fixed-term in office; (2) the principle of lesser control intensity (deference) of the agency acts; (3) the prohibition of contingency of agencies’ budgetary resources; and (4) the prohibition of agency powers suppression. Otherwise, the institutional capacity of agencies will be diminished and their neutral action in technical matters will be compromised.

This paper shows how enhanced autonomy and technical impartiality can be useful for better regulatory governance in other countries, preventing them from suffering from the same problems that have occurred in Brazil.

The research approach is based on the concept that a failure event is rarely random and is often generated by a chain of previous events connected by a sort of domino effect. Thus, the purpose of this study is the optimal selection of the components to predictively maintain on the basis of their failure probability, under budget and time constraints.

Assets maintenance is a major challenge for any process industry. Thanks to the development of Big Data Analytics techniques and tools, data produced by such systems can be analyzed in order to predict their behavior. Considering the asset as a social system composed of several interacting components, in this work, a framework is developed to identify the relationships between component failures and to avoid them through the predictive replacement of critical ones: such relationships are identified through the Association Rule Mining (ARM), while their interaction is studied through the Social Network Analysis (SNA).

A case example of a process industry is presented to explain and test the proposed model and to discuss its applicability. The proposed framework provides an approach to expand upon previous work in the areas of prediction of fault events and monitoring strategy of critical components.

The novel combined adoption of ARM and SNA is proposed to identify the hidden interaction among events and to define the nature of such interactions and communities of nodes in order to analyze local and global paths and define the most influential entities.

This paper examines the relationship between marketing automation emergence and the marketers' use of heuristics in their decision-making processes. Heuristics play a role for the integration of human decision-making models and automation in augmentation processes, particularly in marketing where automation is widespread.

This study analyzes qualitative data about the impact of marketing automation on the scope of heuristics in decision-making models, and it is based on evidence collected from interviews with twenty-two experienced marketers.

Marketers make extensive use of heuristics to manage their tasks. While the adoption of new automatic marketing tools modify the task environment and field of use of traditional decision-making models, the adoption of heuristics rules with a different scope is essential to defining inputs, interpreting/evaluating outputs and control the marketing automation system.

The paper makes a contribution to research on the relationship between marketing automation and decision-making models. In particular, it proposes the results of in-depth interviews with senior decision makers to assess the impact of marketing automation on the scope of heuristics as decision-making models adopted by marketers.

Contract risk management has become a critical mission, as contract issues may lead to a loss of vast amounts of money to parties involved or cause project failure. This study sought to identify effective management strategies to mitigate construction contract issues that might emerge during construction.

A quantitative research approach was adopted for the study. Structured questionnaires made up of close-ended questions were distributed to construction professionals in South Africa via the SurveyMonkey platform. The data were then analysed using descriptive statistics.

The findings indicate that the critical sources of contract-related disputes are ambiguous definitions of the contract parties' scope of their rights and obligations, lack of precise arrangements regarding the calculation of contractual penalties for failure to meet the deadline, lack of detailed specification of the works and specific milestones, lack of provisions regulating changes to the project documentation during the construction stage, an excessive amount of contractual penalties on contractor's side and lack of provisions regarding the rules of performing additional and replacement works and their settlement. However, for these disputes to be effectively managed, strategies such as reduction uncertainties in project's phases, setting up contingency plans, construction guarantee, extension of time claims, payment guarantee, retention and escalation clause should be implemented by the parties involved.

Even though the empirical study focused on construction professionals in South Africa, the findings could be applied to other countries outside of South Africa.

To effectively manage and prevent contract disputes from averting project failures and losses to parties involved in the contract, construction professionals need to be aware of strategies that must be implemented before and during the project execution. If well implemented, these strategies will help a construction project be successful and experience fewer contractual disputes.

The study has identified the knowledge gap concerning suitable contract risk management strategies available for implementation to effectively prevent any contract parties from losing money, time and project failure.