This project aims to study the performance of two reinforcement machine learning algorithms, namely the Proximal Policy Optimization and Soft Actor Critic, in the simulation of autonomous sailboats ...and their response to different wind directions while avoiding obstacles detected by image analysis and following defined target check-points. Also, the effect of the imitation learning algorithms Behavioral Cloning and Generative Adversarial Imitation Learning combined with the first mentioned algorithms is studied. The proposed scenarios consist of areas filled with random static or moving obstacles and with the presence of favorable or crosswinds. The motivation for the project comes from the lack of studies of the mentioned algorithms in autonomous sailboats, issue which the current study tries to address. The Unity platform and ML-Agents machine learning toolkit are used for development and the methodology that guides the project can be similarly applied to other reinforcement learning problems. Through agent training, it is possible to compare the results and observe that the Proximal Policy Optimization obtains better performance within the proposed scenarios, both with and without the support of imitation learning algorithms.
The main strategy of interrupting Trypanossoma cruzi transmission is to control the vector populations. Studies of new agents with activity against these vectors have a priority interest. This study ...evaluated the insecticidal activity of the essential oil of Myrciaria floribunda against nymphs of R. prolixus. M. floribunda was collected in Jurubatiba Sandbank (southeastern Brazil). Leaves were extracted by hydrodistillation and the essential oil analyzed by mass spectrometry and flame ionization gas chromatography. The pure essential oil at various dilutions or purified 1,8-cineole was topically applied to R. prolixus. Sesquiterpenes were the main group detected followed by monoterpenes. M. floribunda essential oil, but not 1,8-cineole, significantly increased mortality and disrupted metamorphosis. Overaged nymphs and juvenoid-like insects were also observed. Our data indicate the special metabolites in the essential oil of M. floribunda as promising candidates for studying insecticidal activity and for use as environmentally friendly control compounds to Chagas disease vectors.
Debates regarding sustainable management have become notorious, significant and pertinent to contemporary society. This perspective is justified by the fact that modern management should address ...concerns of a fully aware audience regarding limits to be imposed on the use of natural/cultural resources and the negative impact of operations on the environment and on society and individuals. Undoubtedly, this assumption is even more important in industries where the power of socioenvironmental, cultural and economic transformation is increasingly latent, such as in the case of hotels. First, this article introduces a bibliometric analysis that exposes sustainable criteria verified in current management models, which allows for an identification among hotel companies for a predisposition for environmental and external social responsibility. Second, a primary contribution lies in structuring more holistic criteria, integrated in the internal/external hotel organizational background, in a manner that will enable organizations to help protect the environment as well as sociocultural, political and economic aspects of society.
•Criteria and strategic principles that legitimize the sustainable management.•Modern hotel sustainability is limited, mostly, to environmental dimension.•Sociocultural, economic and political criteria are important for sustainable hotels.•The article claims for an integrated and participative hotel management.
Numerous events over the last six decades have made it necessary to reformulate the economic development models proposed by capitalism. In this context, sustainability has emerged with the aim of ...balancing corporate interests with stakeholders’ needs. To facilitate this aim, organizations must build a productive management relationship with their stakeholders and thus understand the implications of their operations in all dimensions of sustainability. In this context, due to the potential negative environmental, cultural, and social impacts of tourism, hotels have a responsibility to act in a sustainable manner. Therefore, the objective of this research was to identify criteria against which hotels can measure their impacts. A quali-quantitative study was developed based on the following stages: (1) preparing a workshop that enabled the analysis of 66 possible criteria when designing sustainable hospitality; (2) understanding the degree of importance of each of these criteria based on a semistructured questionnaire applied to 177 professionals linked to the hotel market and academia; and (3) using software R to run a confirmatory factor analysis that validated 39 criteria distributed with regard to the following dimensions: environmental (11), social (10), cultural (4), economic (8), and political (6). We conclude that using these criteria will allow hotel managers to develop more holistic, systemic, integrated, and participatory strategies and to play an active role in building economically profitable, socially just, culturally compatible, and environmentally responsible societies.
•Hotel businesses should be protagonists of sustainable tourism development.•Criteria and strategic principles that legitimized sustainable management.•Environmental, sociocultural, economic and political criteria for a sustainable hotel.
Planning processes undergo unexpected changes with frequent re-planning, resulting in disconnection with business strategies, loss of coherence between planning horizons, and failure to achieve ...expected organizational results. The purpose of this paper is to identify the factors that cause changes, selecting the most critical ones, as well as their effects on planning processes. To achieve this objective, a systematic literature review and an empirical study in an oil and gas company were carried out. Five factors of greater influence on the processes were identified: organizational pressures, information inconsistencies, schedule changes, estimates and shared resources. In this study, the analysis of the "schedule changes" factor is presented, with its possible causes and their effects. Most respondents indicated that schedule changes is the factor of greatest impact in portfolio management, project management, and shared resources management, among the five studied ones, due to repriorizations, project insertion and exclusion, limitations of resources not considered in the portfolio, among others. This work presents an innovative look at a complex scenario that is the multi-project portfolio management with shared resources in the petroleum industry, being an important input for the organizations in promoting a more effective project management. Project managers and teams will be able to identify and treat possible factors present in their processes, obtaining better results in the implementation of new enterprises. Keywords: Portfolio; Projects; Shared Resources; Operations; Influencing Factors. Os processos de planejamento sofrem mudancas inesperadas, com replanejamentos frequentes, tendo como consequencias a desconexao com as estrategias empresariais, com os horizontes de planejamento e o nao atingimento dos resultados organizacionais esperados. A proposta deste trabalho e identificar os fatores de mudancas, selecionando os mais criticos, e seus efeitos nos processos de planejamento. Para isto, foi realizada uma revisao sistematica da literatura e um estudo empirico em uma empresa de oleo e gas, por meio de uma pesquisa de campo. Foram identificados cinco fatores de maior influencia: pressoes organizacionais, inconsistencias das informacoes, mudancas devidas a programacao, estimativas e compartilhamento. Neste estudo e apresentada a analise do fator "mudancas devidas a programacao", com as possiveis causas e efeitos, considerado, pela maioria dos respondentes, como o de maior impacto nos processos de gestao do portfolio, gerenciamento de projetos e gestao dos recursos compartilhados, devido a repriorizacoes, insercao e exclusao de projetos, cronogramas pouco representativos, limitacao de recursos nao considerada no portfolio, entre outros. O trabalho apresenta um olhar inovador sobre um cenario complexo que e a gestao de multiplos projetos com recursos compartilhados na industria do petroleo, sendo um importante insumo para as organizacoes na promocao de um gerenciamento de projetos mais efetivo. Espera-se que este estudo possa contribuir com gerentes e equipes de projetos na identificacao e tratamento de possiveis fatores presentes em seus processos, obtendo melhores resultados na implantacao de novos empreendimentos. Palavras-chave: Portfolio; Projetos; Recursos Compartilhados; Operacoes; Fatores Influenciadores.
Planning processes undergo unexpected changes with frequent re-planning, resulting in disconnection with business strategies, loss of coherence between planning horizons, and failure to achieve ...expected organizational results. The purpose of this paper is to identify the factors that cause changes, selecting the most critical ones, as well as their effects on planning processes. To achieve this objective, a systematic literature review and an empirical study in an oil and gas company were carried out. Five factors of greater influence on the processes were identified: organizational pressures, information inconsistencies, schedule changes, estimates and shared resources. In this study, the analysis of the "schedule changes" factor is presented, with its possible causes and their effects. Most respondents indicated that schedule changes is the factor of greatest impact in portfolio management, project management, and shared resources management, among the five studied ones, due to repriorizations, project insertion and exclusion, limitations of resources not considered in the portfolio, among others. This work presents an innovative look at a complex scenario that is the multi-project portfolio management with shared resources in the petroleum industry, being an important input for the organizations in promoting a more effective project management. Project managers and teams will be able to identify and treat possible factors present in their processes, obtaining better results in the implementation of new enterprises.
Gestões sustentáveis são influenciadas por fatores socioambientais, culturais e econômicos que repercutem, positiva ou negativamente, por meio dos impactos produzidos por suas relações com a ...sociedade e o meio ambiente. Justamente por isso, suas estratégias devem assumir preceitos interdisciplinares que supram as expectativas econômicas dos stakeholders e assumam responsabilidades coerentes no seu macroambiente. Assim, reconhece-se que tais gestões devem ser entendidas enquanto um emaranhado complexo e indissociável de responsabilidades socioculturais, políticas, econômicas e ambientais. Contudo, por meio de três estudos bibliométricos – pautados por pressupostos qualitativos – os autores apresentaram o comprometimento do segmento hoteleiro acerca dessa temática, notando-se: uma predileção por responsabilidades socioambientais; a opção pela não construção de uma gestão participativa. Contextualização essa que ratifica a ânsia por critérios que favoreçam a solidariedade intergeracional, permitindo atender à lógica econômica vigente e propor uma estrutura organizacional socialmente justa, economicamente rentável, culturalmente compatível e ambientalmente amigável.
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