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Brazil has been increasing its participation in the international trade market, mainly due to agricultural and forestry products, as in the case of soybeans and cellulose. This growth led to the expansion of the logistics infrastructure and its use. An important example of this trend is the port of São Luís, MA, in northern Brazil, which saw an increase in exports via rail (more than 200% growth in 6 years) and, consequently, an increase in the circulation of trains within its port complex.

This work proposes a mixed-integer linear programming model for the daily train scheduling problem at this port. All trains operated by VLI, a logistics company, are scheduled to minimize the departure times in order to improve the dwell time of freight train cars.

The railroad system in this Brazilian port consists of two classification yards, five terminals and a double-track railway for circulation. Different products such as grains, minerals, cellulose, and fuels are transported. The model also incorporates different operations at terminals and occupation restrictions due to maintenance and the physical flow of other third-party logistics companies. These features are modeled through a preprocessing step. In this phase, a series of auxiliary sets are defined to simplify constraints, circulation options are mapped, and the double-track is divided into segments based on the transit time with the objective to control track occupation.

This preprocess step also reduces the model complexity and, consequently, the computational time to solve it, as shown in the numerical tests using real-world operational data.

The main gains of the project were a reference train timetable for peak days, standardization of train crossing options, and a support tool for traffic adjustments with other rail operators.

This study analyses the factors that can influence the quality of service provided by the bus rapid transit (BRT) system in the state of Pernambuco. It is incipient, considering that the system was implemented in this state in 2014 to the World cup. In this context, the purpose of this paper is to identify the factors considered important for the services provided by this system and their impact on perceived quality.

The authors analyzed the data using exploratory factorial analysis, and linear and quantile regression techniques. Regarding the classification, this research is applied, exploratory, descriptive and in the form of a case study describing the situation experienced by the users of BRT in Pernambuco.

The results showed that it was possible to identify five factors that impact the level of satisfaction of the offered services: fluency in the provision of the service; staff training; physical conditions in the provision of the service; convenience/accessibility; and integration between transport lines.

With initial identification, factors 1, 3, 4 and 5 have been found to have an impact on overall service quality in a positive and statistically significant way. Factors 3 and 4 have a different impact with high- and low-quality standard perceived by users, and these should be the guiding elements by companies in establishing actions to improve the services offered.

This paper presents an algorithm that can elicitate (infer) all or any combination of elimination and choice expressing reality (ELECTRE) Tri-B parameters. For example, a decision maker can maintain the values for indifference, preference and veto thresholds, and the study’s algorithm can find the criteria weights, reference profiles and the lambda cutting level. The study’s approach is inspired by a machine learning ensemble technique, the random forest, and for that, the authors named the study’s approach as ELECTRE tree algorithm.

First, the authors generate a set of ELECTRE Tri-B models, where each model solves a random sample of criteria and alternates. Each sample is made with replacement, having at least two criteria and between 10% and 25% of alternates. Each model has its parameters optimized by a genetic algorithm (GA) that can use an ordered cluster or an assignment example as a reference to the optimization. Finally, after the optimization phase, two procedures can be performed; the first one will merge all models, finding in this way the elicitated parameters and in the second procedure, each alternate is classified (voted) by each separated model, and the majority vote decides the final class.

The authors have noted that concerning the voting procedure, nonlinear decision boundaries are generated and they can be suitable in analyzing problems of the same nature. In contrast, the merged model generates linear decision boundaries.

The elicitation of ELECTRE Tri-B parameters is made by an ensemble technique that is composed of a set of multicriteria models that are engaged in generating robust solutions.

The present research aims to evaluate the quality of services provided by the Basic Health Units (UBS) of the Unified Health System (SUS) located in the city of Recife, in the state of Pernambuco, Brazil, using the Kano model integrated with the dimensions of quality proposed by the service quality (SERVQUAL) model.

The research was classified as bibliographic, descriptive, quantitative and surveyable. A structured questionnaire based on the Kano Model integrated with the dimensions of quality proposed by the SERVQUAL model, applied online through Google Forms. The questionnaires were distributed on social networks, obtaining a non-probabilistic sample of 120 individuals, collected for convenience.

Through the analysis of the Kano Model, it was possible to observe that all the investigated attributes are classified as one-dimensional. Among the attributes that deserve to be highlighted are attributes “Clean and pleasant environment”, “Reliability and security of information”, “Knowledge of employees to perform services”, “Service performed in the promised time”, “Polite and kind staff in dealing with users” and “Effectiveness of the service provided” due to having the longest intervals when considering the satisfaction and dissatisfaction coefficients, above 1.575. These attributes must be considered as critical priorities when implementing improvements, since their presence considerably increases users' satisfaction, as well as their absence generates great dissatisfaction.

The research is original and justified by the potential use of a quality assessment tool in the public health service, especially primary care. It is noteworthy that there are few works that integrate the Kano and SERVQUAL models applied in the public health service and that this integration can contribute to the national and international literature, mainly in the identification and prioritization of areas for improvement.

The purpose of this paper is to establish the need and the importance of adopting a structured model to support the decisions by using a multicriteria focus to guide drawing up a methodological framework. In addition, this study considers the maturity level of the organization, and the importance of continuous improvement after implementing ISO 9001.

This study presents a scientific technical foundation of the qualifying and selection criteria of the consultancy and Accredited Certification Body (ACB) by using ISO standards, and the guidance document CB25, which is related to quality. Finally, a numeric application with realistic data is undertaken using the PROMETHEE II method, and the GAIA plan.

The development of this study provides a new insight into the importance for selecting consultancy, and certification services in order to implement quality management systems within organizations.

The current study is limited to the quality management services. If necessary to apply the same model to other areas, it is necessary looking for documents and regulations of this field. In addition, this model is focussed on a model for small or medium companies, which are still trying to achieve a higher position in the sector, and do not have experts in quality management.

The differential of this study is the foundation of the criteria for the proposed model. Other studies choose these criteria without any scientific basis. On the other hand, this study goes over many documents.

Ever since Mark Weiser coined the term “ubiquitous computing” (ubicomp) in 1988, there has been a general interest in proposing various solutions that would support his vision. However, attacks targeting devices and services of a ubicomp environment have demonstrated not only different privacy issues, but also a risk of endangering user’s life (e.g. by modifying medical sensor readings). Thus, the aim of this paper is to provide a comprehensive overview of security challenges of ubicomp environments and the corresponding countermeasures proposed over the past decade.

The results of this paper are based on a literature review method originally used in evidence-based medicine called systematic literature review (SLR), which identifies, filters, classifies and summarizes the findings.

Starting from the bibliometric results that clearly show an increasing interest in the topic of ubicomp security worldwide, the findings reveal specific types of attacks and vulnerabilities that have motivated the research over the past decade. This review describes most commonly proposed countermeasures – context-aware access control and authentication mechanisms, cryptographic protocols that account for device’s resource constraints, privacy-preserving mechanisms, and trust mechanisms for wireless ad hoc and sensor networks.

To the best of our knowledge, this is the first SLR on security challenges in ubicomp. The findings should serve as a reference to an extensive list of scientific contributions, as well as a guiding point for the researchers’ novel to the security research in ubicomp.

In this chapter, we outline the statistical consequences of neglecting structural breaks and regime switches in autoregressive and GARCH models and propose two strategies to approach the problem. The first strategy is to identify regimes of constant unconditional volatility using a change point detector and estimate a separate GARCH model on the resulting segments. The second approach is to use a multiple-regime GARCH model, such as the Flexible Coefficient GARCH (FCGARCH) specification, where the regime-switches are governed by an observable variable. We apply both alternatives to an array of financial time series and compare their forecast performance.

Although childless women comprise around 17% of women aged 65 and over in the US (Census Bureau, US, 2016) and up to 20% in other places in the world (Dykstra, 2009), the intersection of childlessness, female gender and old age has not been as widely explored as is necessary; older women have historically been and continue to be overlooked in feminist research compared to other groups of women (Browne, 1998; Ray, 1996; Twigg, 2004). Therefore, how childlessness affects identity and identity, childlessness in later life is not well understood. Our analysis considered: How do never-married, childless women identify themselves in terms of age? What are the key features of such an age identity? And, do these identities align with progress narratives or narratives of decline? For this chapter, interviews with 53 older women (22 African American, 31 White) aged 60 and over, who described themselves as never married and without biological children, were analysed. Questions were semi-structured and open-ended and covered background health information, a life story interview, questions about social networks, various forms of generativity and the sample’s views about the future. Overall, these women negotiated their age identity not necessarily in relation to others (e.g. child, spouse) but in relation to themselves as social actors with an orientation towards the future – what will tomorrow bring? These forward-thinking narratives point to a new and important way to consider progress narratives and to rethink trajectories of the experience of aging.