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The closing of Samir's Mohammedia refinery in August 2015 due to financial constraints has dramatically affected the fuel oil market in Morocco. In this paper, we assess the economic and environmental impacts of the disruption of Morocco's only refinery activities. We can isolate the oil refinery sector associated with Samir in a fully specified interregional input-output database, considering 20 industries in 12 Moroccan regions. We base our empirical strategy on the “hypothetical extraction” method, which serves as the methodological anchor to isolate the systemic measures of value-added and CO2 emissions related to the refinery activities in a typical year of operation. The overall impact of the shutdown is 4.4% of the country's output, with more substantial regional effects faced by Grand Casablanca-Settat, followed by its neighboring regions.

This study aims to assess the nature and the magnitude of the productive links of consumer operations made possible by the revenue generated by ride-hailing. We seek to map the interdependencies established between the consumption decisions of drivers that use the 99 app, a leading e-hailing provider, with other sectors and segments of the Brazilian economy. The dataset comprises operational information from 99 and an interregional input-output table for the Brazilian economy. In 2019, the intermediated trips only for 99 unfolded in more than 12 billion (BRL) added to the Brazilian GDP (equivalent to 0.18% of the total), each sector of the Brazilian economy being affected in different magnitudes. This study shows the degree of interdependence between these sectors and 99's business. In addition to the value added, indirect taxes were collected in the order of 1 billion (BRL), and 267.9 thousand jobs were generated.

O objetivo desta pesquisa foi identificar a relevância da consistência e da convergência contábil no nível de transparência dos municípios do Estado de Pernambuco. A amostra contou com os 184 municípios do Estado de Pernambuco. O ano analisado foi o de 2015. A análise revelou que é de 42%, em média, a transparência dos municípios pernambucanos em relação à gestão pública. Houve relação positiva e estatisticamente significativa para duas variáveis, o PIB e o tamanho da população, o que indica que, quanto maior for o PIB e a população, mais transparentes são na gestão pública serão os munícipios. Por fim, na ANACOR, os dois índices são independentes (não estão relacionados). Assim, podemos afirmar que não se regista uma relação entre o índice de transparência municipal e o índice de consistência e convergência contábil.

O estudo investigou a influência da satisfação e da reputação organizacional sobre a lealdade no contexto da economia compartilhada, articulando estes elementos com a teoria do comportamento planejado (TPB). Um modelo teórico-empírico foi testado por meio de técnicas multivariadas a partir dos dados obtidos através de uma survey com 231 usuários do Uber. Os resultados mostraram que as influências da satisfação e da reputação sobre a intenção comportamental de lealdade ao Uber são significantes se mediadas pela atitude em relação à plataforma; o controle comportamental percebido não é preditor da lealdade; e o efeito das normas subjetivas sobre a lealdade também ocorre somente quando moderado pela atitude.

The maintenance paradigm has evolved over the last few years and companies that want to remain competitive in the market need to provide condition-based maintenance (CBM). The diagnosis and prognosis of the health status of equipment, predictive maintenance (PdM), are fundamental strategies to perform informed maintenance, increasing the company’s profit. This article aims to present a diagnosis and prognosis methodology using a hidden Markov model (HMM) classifier to recognise the equipment status in real time and a deep neural network (DNN), specifically a gated recurrent unit (GRU), to determine this same status in a future of one week. The data collected by the sensors go through several phases, starting by cleaning them. After that, temporal windows are created in order to generate statistical features of the time domain to better understand the equipment’s behaviour. These features go through a normalisation to produce inputs for a feature extraction process, via a principal component analysis (PCA). After the dimensional reduction and obtaining new features with more information, a clustering is performed by the K-means algorithm, in order to group similar data. These clusters enter the HMM classifier as observable states. After training using the Baum–Welch algorithm, the Viterbi algorithm is used to find the best path of hidden states that represent the diagnosis of the equipment, containing three states: state 1—“State of Good Operation”; state 2—“Warning State”; state 3—“Failure State”. Once the equipment diagnosis is complete, the GRU model is used to predict the future, both of the observable states as well as the hidden states coming out from the HMM. Thus, through this network, it is possible to directly obtain the health states 7 days ahead, without the necessity to run the whole methodology from scratch.

Condition-Based Maintenance (CBM), based on sensors, can only be reliable if the data used to extract information are also reliable. Industrial metrology plays a major role in ensuring the quality of the data collected by the sensors. To guarantee that the values collected by the sensors are reliable, it is necessary to have metrological traceability made by successive calibrations from higher standards to the sensors used in the factories. To ensure the reliability of the data, a calibration strategy must be put in place. Usually, sensors are only calibrated on a periodic basis; so, they often go for calibration without it being necessary or collect data inaccurately. In addition, the sensors are checked often, increasing the need for manpower, and sensor errors are frequently overlooked when the redundant sensor has a drift in the same direction. It is necessary to acquire a calibration strategy based on the sensor condition. Through online monitoring of sensor calibration status (OLM), it is possible to perform calibrations only when it is really necessary. To reach this end, this paper aims to provide a strategy to classify the health status of the production equipment and of the reading equipment that uses the same dataset. A measurement signal from four sensors was simulated, for which Artificial Intelligence and Machine Learning with unsupervised algorithms were used. This paper demonstrates how, through the same dataset, it is possible to obtain distinct information. Because of this, we have a very important feature creation process, followed by Principal Component Analysis (PCA), K-means clustering, and classification based on Hidden Markov Models (HMM). Through three hidden states of the HMM, which represent the health states of the production equipment, we will first detect, through correlations, the features of its status. After that, an HMM filter is used to eliminate those errors from the original signal. Next, an equal methodology is conducted for each sensor individually and using statistical features in the time domain where we can obtain, through HMM, the failures of each sensor.

Resumo: Este artigo analisa a trajetória tecnológica do cultivo de camarão no Nordeste brasileiro e suas implicações ou limitações para a adoção de inovações sustentáveis ambientalmente. Desse modo, uma abrangente pesquisa empírica foi realizada, usando dados secundários e entrevistas semiestruturadas com vários agentes envolvidos no cultivo do camarão. Assim, foi possível identificar o perfil desse setor de atividade com base em sua trajetória de desenvolvimento desde o início de sua produção no Brasil. Os principais resultados do estudo apontam que a trajetória tecnológica dessa indústria revelou limitações, mas, também, algumas oportunidades para a geração de inovações sustentáveis, especialmente no estágio atual.

Purpose: To evaluate the fracture load and survival rate of weakened and non-weakened roots restored with different intracanal posts. Methods: Eighty teeth (16 mm) were prepared to a length of 10 mm with a custom drill. Fifty roots were weakened with a tapered diamond drill, and 30 roots were not. The specimens were embedded with acrylic resin up to 3 mm from the coronal aspect, and the periodontal ligament was simulated. The 50 weakened roots were restored with (n=10) CPC-gold (cast post and core made of gold alloy), CPC-Ni (cast post and core made of Ni-Cr alloy), FP (glass fiber posts), FP-W (glass fiber posts with a wider coronal diameter), and FP-CR (fiber posts relined with composite resin). The 30 nonweakened roots were restored with (n=10) CPC-gold, CPC-Ni, and FP. All of the posts were adhesively cemented. All of the specimens were mechanically cycled (37°C, 45°, 130 N, 2.2 Hz, and 1.5 million pulses) and evaluated after every 5 X 104 cycles to evaluate the presence of cracks as a primary outcome (event). The specimens that survived cycling were subjected to a fracture load test (load application on the palatal aspect at a 45° inclination). Failure mode was classified as favorable (above the simulated bone level) and catastrophic (below the simulated bone level). Survival rates were estimated using the Kaplan-Meier method. Fracture load data were analyzed using the Kruskal-Wallis test (α=0.05) for weakened roots, one-way analysis of variance, and Tukey test (p<0.05) for non-weakened roots, and Student f-test (p<0.05) compared nonweakened vs weakened roots for the same post system. Results: For the preliminary survival results, FP-W showed a higher survival rate when compared with CPC (gold/Ni). For the fracture load (N), the statistical analysis (p<0.0001) presented differences among the weakened groups: CPC-gold (541.4) = CPC-Ni (642.6) > FP (282.2) = FP-W (274.1) = FP-RC (216.6). No differences were observed for the groups that were nonweakened (majority of favorable failures): CPC-gold (459.3) = CPC-Ni (422.0) = FP (347.9). Weakened roots restored with CPC-gold promoted high values of load fracture and unfavorable failure rates. Conclusion: Cast post and cores or fiber posts can be used for restoring nonweakened roots. However, for weakened roots, a fiber post with a wider cervical emerging diameter appears to be a better alternative when compared with cast post and cores. [ABSTRACT FROM AUTHOR]

QUANDO, na Idade Média, passou a instrução das mãos do clero para as de propulsores escolares, o ensino nas escolas de língua vernácula tinha uma forma rudimentar e servia as classes da sociedade a que era destinado; [...]

The availability maximization is a goal for any organization because the equipment downtime implies high non-production costs and, additionally, the abnormal stopping and restarting usually imply loss of product’s quality. In this way, a method for predicting the equipment’s health state is vital to maintain the production flow as well as to plan maintenance intervention strategies. This paper presents a maintenance prediction approach based on sensing data managed by Hidden Markov Models (HMM). To do so, a diagnosis of drying presses in a pulp industry is used as case study, which is done based on data collected every minute for three years and ten months. This paper presents an approach to manage a multivariate analysis, in this case merging the values of sensors, and optimizing the observable states to insert into a HMM model, which permits to identify three hidden states that characterize the equipment’s health state: “Proper Function”, “Alert state”, and “Equipment Failure”. The research described in this paper demonstrates how an equipment health diagnosis can be made using the HMM, through the collection of observations from various sensors, without information of machine failures occurrences. The approach developed demonstrated to be robust, even the complexity of the system, having the potential to be generalized to any other type of equipment.

O artigo faz uma análise da forma de inserção da carcinicultura do Nordeste, em particular dos Arranjos Produtivos Locais - APLs de cultivo de camarão do estado do Ceará, em cadeias globais de produção, bem como sua estrutura de governança. Isto porque os sistemas de cultivo destes crustáceos se concentram no Nordeste, sendo, na atualidade, o Ceará o maior produtor do Brasil na forma cultivado, expressando, ao longo de suas bacias hidrográficas, dois APLs bem característicos (litorais leste e oeste), que estiveram intensamente inseridos em mercado internacional por meio de cadeias globais de produção. O estudo teve por base um levantamento de dados secundários e entrevistas junto aos gestores e proprietários das empresas e outros agentes dos APLs. As principais evidências da pesquisa apontam que a inserção das empresas dos APLs ainda ocorre de forma dependente dos grandes compradores internacionais e os benefícios gerados, em grande parte, são apropriados fora da esfera produtiva, influenciando as capacitações produtivas e inovativas dos produtores locais. A estrutura de coordenação é verticalizada, demonstrado certo grau de assimetria nas relações de poder entre diferentes segmentos de agentes, sendo os principais estágios da cadeia de valor, em parte, controlados por agentes externos aos arranjos.

Este artículo es un análisis de la trayectoria tecnológica del cultivo de camarón en el nor-deste de Brasil y sus implicaciones en el proceso de innovación más sostenible del segmento, lo que le permite rastrear su perfil en función de la evolución en el desarrollo desde su origen hasta la actualidad. Para su sistematización se ha utilizado una amplia investigación empírica utilizando datos secundarios y encuestas semiestructuradas con diversos agentes del sector productivo. Como resultado se observa que el progreso tecnológico revela limitaciones; sin embargo, también genera oportunidades para innovar de manera más sostenible, en especial en la fase actual de su trayectoria.

This paper presents a case study and a model to predict maintenance interventions based on condition monitoring of diesel engine oil in urban buses by accompanying the evolution of its degradation. Many times, under normal functioning conditions, the properties of the lubricants, based on the intervals that manufacturers recommend for its change, are within normal and safety conditions. Then, if the lubricants’ oil condition is adequately accompanied, until reaching the degradation limits, the intervals of oil replacement can be enlarged, meaning that the buses’ availability increases, as well as their corresponding production time. Based on this assumption, a mathematical model to follow and to manage the oil condition is presented, in order to predict the next intervention with the maximum time between them, which means the maximum availability.

A associação do maior número de artroplastias totais de joelho com a maior expectativa de vida da população tem levado a mais complicações de longo prazo, que se somam à baixa qualidade óssea dos pacientes mais idosos e culminam, muitas vezes, em fraturas periprotéticas. Este complexo problema ortopédico tem apresentação clínica muito variável, podendo acometer quaisquer dos ossos do joelho e levar a resultados desastrosos, em virtude de sua difícil solução. O seu tratamento exige do ortopedista amplo conhecimento tanto de técnicas de artroplastia como de osteossíntese, além de elaborado arsenal terapêutico como, por exemplo, acesso a banco de ossos.The increasing number of total knee arthroplasties, in combination with the population's longer life expectancy, has led to a greater number of long-term complications. These complications are also correlated with poor bone quality in the elderly and often result in periprosthetic fractures. This complex orthopedic problem has very diverse clinical presentation, possibly afflicting periprosthetic fracture may happen in any bone that constitutes the knee and, due to the difficulty of finding a solution, may lead to disastrous outcomes. The treatment demands broad knowledge from the orthopedic surgeon, not only regarding arthroplasty techniques, but also osteosynthesis, as well as an elaborate therapeutic including, for example, access to a bone bank.

Bancos de ossos são necessários para prover material biológico para uma série de procedimentos ortopédicos. A crescente necessidade de tecidos musculoesqueléticos para transplante é decorrente do desenvolvimento de novas técnicas cirúrgicas e fez com que diversos serviços se dispusessem a ter sua própria fonte de tecidos para transplante. Para aumentar a segurança dos tecidos transplantados, normas foram impostas pelo governo para o funcionamento dos bancos, o que limitou o número de instituições autorizadas. O bom desempenho de um banco de ossos depende de um rígido controle de todas as etapas, passando pela formação de equipes bem treinadas para captação, pela seleção de doadores, pela realização de diversos exames nos tecidos captados e pelo controle rigoroso das técnicas de processamento utilizadas. A associação desses fatores faz com que a abrangência do uso e do número de pacientes receptores seja ampliada, a contaminação de tecidos seja de incidência estatisticamente desprezível e haja rastreabilidade entre doadores e receptores. Este trabalho descreve as considerações técnicas quanto ao funcionamento de um banco, uso de enxertos e aplicações ortopédicas, bem como aspectos éticos e principais obstáculos enfrentados.Bone banks are necessary to provide biological material for a series of orthopedic procedures. The growing need for musculoskeletal tissues for transplantation is due to the development of new surgical techniques, and has made it so that a variety of services were willing to have their own source of tissue for transplantation. To increase the safety of transplanted tissues, standards for the operation of banks were imposed by the government, which limited the number of authorized institutions. The good performance of a bone bank depends on strict control of all stages, from the formation of well-trained teams for capturing, for donor selection, for conducting various tests on the tissues obtained, and by the strict control of the processing techniques used. The combination of these factors makes it so that the scope of use and the number of recipient patients increases, the incidence of tissue contamination is statistically insignificant, and that there is traceability between donors and receptors. This paper describes the technical considerations regarding the functioning of a bank, use of grafts and orthopedic applications, as well as ethical aspects and the main obstacles encountered.

Este artigo é unha análise da traxectoria tecnolóxica do cultivo de camarón no nordeste do Brasil e as súas implicacións no proceso de innovación máis sostible do segmento, o que lle permite rastrexar o seu perfil en función da evolución no desenvolvemento desde a súa orixe ata a actualida-de. Para a súa sistematización utilizouse unha ampla investigación empírica utilizando datos secun-darios e enquisas semiestruturadas con diversos axentes do sector produtivo. Como resultado obsér-vase que o progreso tecnolóxico revela limitacións; porén, tamén xera oportunidades para innovar de maneira máis sostible, en especial na fase actual da súa traxectoria.

O sistema produtivo e inovativo do cultivo de camarão na região Nordeste do Brasil apresenta características específicas e com diferentes tipos de interação e de cooperação entre os agentes envolvidos. Este artigo objetiva analisar a dinâmica deste sistema a partir das relações entre as instituições presentes, a sua forma de organização, o regime tecnológico e as principais fontes de informações para os processos de aprendizado e geração de inovações. Observa-se que parte das inovações tecnológicas adotadas pelas grandes empresas é resultante de spin-offs das universidades e centros de pesquisa, ao passo que as pequenas e médias empresas utilizam como principais fontes de inovação os fornecedores de insumos e os clientes/compradores.