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The purpose of this paper is to investigate straw modification by chemical degradation generated by two forms of pretreatment, using citric acid in an autoclave and urea solution with sodium hydroxide at low temperature.

The material was digested and compared in biodigester reactors lined with natural straw, straw pretreated with citric acid, straw pretreated with urea and NaOH, and straw subjected to both the pretreatments. The amount of straw has been delimited to 0, 2.5, 5, 7.5 and 10 percent v/v, and used 20 percent v/v inoculum in all reactors, consisting of 30 percent v/v poultry litter and 70 percent swine wastewater (SW). The experiment was conducted in an incubator kept in mesophilic conditions (35°C).

The results indicate significant change in the studied material, with degradation of lignin as well as hemicellulose and cellulose exposed to further hydrolysis. Spectrophotometric methods were used for monitoring degradation. These methods were efficient in monitoring changes caused by the treatments. When the proposed pretreatments are applied to sugarcane straw, there is a significant gain in biogas production (L g VSR⁻¹). The most appropriate rates for higher methane production in the pretreatments are 2.5 and 5 percent straw-SW. The best results for the anaerobic digestion of sugarcane straw were obtained by pretreating it with citric acid.

This paper shows a new use for the sugarcane straw waste after being pretreated with acid or base for the coproduction of biogas.

This paper aims to explore whether formal, non-formal, and informal learning experiences contribute to developing sustainable development competencies (SDCs) among students in a Principles of Responsible Management Education (PRME) signatory business school.

An online survey based on the students’ learning experiences and a questionnaire on sustainability competencies already validated in the literature were given to a sample of 274 bachelor students at a PRME signatory business school. Nominal variables representing students’ categories were created to test a set of hypotheses developed according to the literature. Because the data was not normally distributed, non-parametric independent-samples Mann–Whitney U test was conducted, and descriptive statistics was used to help the analysis.

The results suggest that a hybrid format with a combination of formal, non-formal and informal learning experiences is essential to maximising the development of SDCs and raising students’ sustainability literacy.

This study is one of the first attempts to understand the importance of a hybrid approach in developing sustainable competencies (SDCs). Future studies could adopt longitudinal analysis to check the development of these competencies over time, assess students from different PRME signatory schools or comparing students to those in non-signatory business schools.

This study provides insight into how business schools could address challenges in developing sustainable competencies through redirecting their educational systems by balancing formal, informal and non-formal learning approaches to educate future responsible leaders.

This research provides evidence on how a hybrid learning approach could maximise the development of sustainable development competencies and, therefore, generating insights for educational policies.

The purpose of this paper is to analyze the aftermath of business failure (BF) by addressing: how the individual progressed and developed new ventures, how individuals changed business behaviors and practices in light of a failure, and what was the effect of previous failure on the individual’s decisions to embark on subsequent ventures.

The authors resort to qualitative methods to understand the aftermath of BF from a retrospective point of a successful entrepreneur. Specifically, the authors undertook semi-structured interviews to six entrepreneurs, three from the north of Europe and three from the south and use interpretative phenomenological analysis.

The authors found that previous failure impacted individuals strongly, being shaped by the individual’s experience and age, and their perception of blame for the failure. An array of moderator costs was identified, ranging from antecedents to institutions that were present in the individual’s lives. The outcomes are directly relatable to the failed experience by the individual. The authors also found that the failure had a significant effect on the individual’s career path.

While predicting the failure of healthy firms or the discovery of the main determinants that lead to such an event have received increasingly more attention in the last two decades, the focus on the consequences of BF is still lagging behind. The present study fills this gap by analyzing the aftermath of BF.

This study aims to investigate the existence of delimitations more suited to the emergence of generations in Brazil, and to assess generational perceptions on constructs of the work environment and their influences on organizational commitment.

The perceptions of 102,540 respondents employed by 394 organizations were classified into nine constructs. The methodology used entailed an initial confirmatory factorial analysis, which was undertaken to investigate the validity of the proposed measurement model. Regression analyses were applied to test the relationship between work environment and commitment.

The results highlight that the Baby Boomer generation attributed more value to the meaning of work and corporate social responsibility. Meaning of work, learning and development were given a high level of importance in the results for Generation X. Generation Y values learning and development, relationships with co-workers and Work-life balance more than the other two generations.

This research is classified as a cross-sectional study that does not allow us to substantiate whether differences between the groups were caused by influence of generations or the age of respondents. Therefore, nationwide surveys capable of offsetting the age effect on generational differences are still necessary. Another constraint is related to the fact that only data from the survey that annually elects the “Best Companies to Work for in Brazil” were used for undertaking this study. Moreover, because all variables were collected simultaneously from the same source, the authors recognize that the results could have problems related to common method biases.

The authors believe that the identification of critical dimensions of workers’ perception regarding the work environment equips human resources professionals with the ability to implement policies and practices that align people management with the differing desires of each generation, effectively ensuring commitment from these professionals.

This study may contribute to researchers by highlighting the need for temporal outlines suited to the Brazilian reality, which might also inspire further research on the country’s generations, even associating them with other themes, such as values, personality and professional motivation.

As the main contributions, the authors have sought to highlight that generational differences may be related to specific periods in each country’s historical context. The authors also show the determining factors influencing each generation’s affective commitment and justify each of their choices.

The purpose of this paper is to provide a management tool to maximise the effective time-to-market of a portfolio given the competitive monitoring activities.

From the constant monitoring of competition and market needs, it is proposed to define a time-to-need, time when the market may consume the product under development and competitor will not provide a solution before. This time-to-need is proposed to be defined by an expert committee in a periodical meeting of the portfolio. Once it is identified the time-to-need and the time-to-market (project management), it is possible to manage resources in order to maximise the portfolio outputs.

The application of the mentioned approach in an automotive industry showed improvements on number of launched new products per year (double) and on number of patented product launched (four times more).

This approach applies on projects of medium to long term (more than two years) because the resource management can consume set up time. The presented results in this work were based in a single case, which can limit the expected results of the application of this methodology.

This approach enables a constant alignment among experts and a better deployment of resources.

This work provides a practical tool to promote better resource allocation in a portfolio. It can also be an enabler of innovation projects once it finds resources potential to fund the more front end work.

In this work, the paper aims to demonstrate the feasibility of plastic optical fiber (POF) based accelerometers for the structural health monitoring (SHM) of civil engineering structures based on measurements of their dynamic response, namely to estimate natural frequencies. These sensors use POFs, combining the advantages of the optical technology with the robustness of this particular kind of fiber. The POF sensor output is directly compared with the signal from an electrical sensor, demonstrating the potential use of such sensors in structural monitoring applications.

Within this work, the paper demonstrates the feasibility of using a low-cost acceleration system based on a POF accelerometer on the dynamic monitoring of a civil engineering structure, aiming its natural frequency evaluation, which is a primary parameter to be used in SHM methods and numerical models calibration.

A low-cost POF-based accelerometer was used in the characterization of a civil engineering structural component, located in a building at the University of Aveiro Campus, being used to estimate its natural frequency with a relative error of 0.36 percent, comparatively to the value estimated recurring to a calibrated electronic sensor.

Optical fiber sensors take advantage of the fibers properties, such as immunity to electromagnetic interference and electrical isolation. They are very attractive for use in hostile environments, like submerse environments or flammable atmospheres where electrical currents might pose a hazard. The advantages of POF itself should also be considered, like resistance to hash environments, robustness, flexibility, low-cost interrogation units and high numeric aperture (lower cost components). The paper demonstrates the feasibility of using a low-cost acceleration system based on a POF accelerometer on the dynamic monitoring of a civil engineering structure, aiming its natural frequency evaluation.

The paper aims to identify the prevailing values of the public sector in Brazil, based on the tri-axial model. The study proposes to capture the dynamics between different values axes of Brazilian public sector as well as to detect cultural differences between genders, level of commitment, and nature of work. An additional contribution is expected in understanding Brazilian values at public sector as a necessary approach to obtain a new order of public administration based on efficiency.

The paper opted for an exploratory study developed within the scope of a larger study aiming to understand the meaning of values in different cultures with an exclusive focus on the public sectors. Using a pre-validated questionnaire, 137 respondents, who work on Brazilian public sector, participated in the survey. A frequency analysis was conducted for various demographic variables. Descriptive statistics were used to understand the profile of the respondents in Brazil's survey. We have used the criteria recommended to all countries that participated in the study.

This empirical work demonstrate that the methodology based on the tri-axial model was able to capture the dynamics between different values axes of Brazilian public sector as well as to detect cultural differences between genders, level of commitment and nature of work. The dominant values perceived in almost every analysis, belong to pragmatic-economic axis such as professionalism, teamwork, adventure, knowledge, and challenge. This strong orientation to pragmatism is consistent with the needs of the Brazilian public sector to have a more entrepreneurial vision and focus on optimization the use of the financial resources.

Because of the chosen sample approach, the research results may lack generalizability.

The paper includes implications for a management based on values as a model to obtain efficiency at public sector in Brazil

This research is part of an international project interesting in investigating values within different countries and cultures. It provides data from a country that belongs to an emergent group of world economy such as BRICs and has different scenery compared to traditional actors of global business.

The purpose of this paper is to use PAM-CRASH, a finite element analysis solver, to assess the performance of a mass production vehicle cross car beam (CCB) under an overlap frontal crash scenario (crashworthiness). Simulation results were reviewed according to what is plausible to register regarding some critical points displacements and, moreover, to identify its stress concentrations zones. Furthermore, it was also computed the CCB modal analysis (noise, vibration and harshness (NVH) assessment) in order to examine if its natural modes are within with the original equipment manufacturer (OEM) design targets.

The available data at the beginning of the present study consisted of the structure CAD file and performance requirements stated by the OEM for NVH. No technical information was available concerning crashworthiness. Taking into account these limitations, it was decided to adapt the requirements for other mass production cars of the same category, as regards dynamic loading. A dynamic explicit code finite element analysis was performed throughout the CCB structure simulating the 120e−3 s crash event. For the modal analysis, there were some necessary modifications to the explicit finite element model in order to perform the analysis in implicit code. In addition, the car body in white stiffness was assigned at the boundaries. These stiffness values are withdrawn from the points where the CCB is attached to the car body’s sheet metal components.

Although the unavailability of published results for this particular CCB model prevents a comparison of the present results, the trends and order of magnitude of the crash simulation results are within the expectations for this type of product. Concerning modal analysis, the steering column first natural frequency has a percent deviation from the design lower bound value of 5.09 percent when local body stiffness is considered and of 1.94 percent with fixed boundary conditions. The other requirement of the NVH assessment regarding a 5 Hz minimum interval between first vehicle CCB mode and the first mode of the steering column was indeed achieved with both boundary configurations.

This study is a further confirmation of the interest of numerical modeling as a first step before actual experimental testing, saving time and money in an automotive industry that has seen an enormous increase of the demand for new car models in the last decade.