Abstract The encounter of professors with cultural diversity has become a common experience in higher education institutions based on the policies of democratization of access to universities in Brazil in the first decades of the 21stcentury. This article presents “points of contact” with diversity in the context of an institution created under the guidelines of international South-South academic cooperation. Through the description of situations experienced in teaching activities, a reflection is sought on the processes of identity construction promoted by agencies associated with the formation of ethnic and national boundaries. Anthropology emerges as a mediator to this encounter in the record of the experience that articulates theory to the post-colonial situations found in teaching relationships, locating interdisciplinary problem-spaces, common values in the context of the administrative structures and a sensitive approach to the history shared by the Community of Portuguese Speaking Countries (CPLP).

Resumo O encontro de docentes com a diversidade cultural dos estudantes passou a ser uma experiência comum nas salas de aula a partir das políticas de democratização do acesso às universidades no Brasil nas primeiras décadas do século XXI. Este artigo apresenta “pontos de contato” com essa diversidade no contexto de uma instituição criada sob as orientações da cooperação internacional acadêmica Sul-Sul. Por meio da descrição de situações vividas em atividades docentes, procura-se uma reflexão sobre os processos de construção identitária promovidos por agenciamentos associados à formação de fronteiras étnicas e nacionais. A antropologia emerge como mediadora desse encontro no registro da vivência que articula teoria às situações pós-coloniais encontradas nas relações de ensino ao encontrar espaços-problema interdisciplinares, valores comuns no contexto de estruturas administrativas, bem como uma aproximação sensível com a história partilhada pela Comunidade dos Países de Língua Portuguesa (CPLP).

BACKGROUND: Egypt used to have one of the highest hepatitis C virus (HCV) infection prevalence rates worldwide, with an estimated HCV prevalence of around 4.5% to 6.7%. OBJECTIVES: To determine the HCV infection incidence rate amid Egyptian patients living with HIV. METHOD: A total of 460 HIV-positive patients were recruited in a retrospective cohort study from Imbaba Fever Hospital, Cairo, between January 2016 and March 2019. The patients had a negative baseline and at least one other HCV antibody test. Hepatitis C virus antibody testing was done by antibody sandwich third-generation enzyme-linked immunosorbent assay. The hepatitis C virus infection incidence rate among HIV-infected patients was calculated using the person-time incidence rate RESULTS: Two hundred and eighteen patients were finally included: 146 (31.7%) patients were excluded for having a positive baseline HCV Ab result and 96 patients were excluded for not having a follow-up HCV Ab test. Eighteen patients had HCV seroconversion (8.3%), achieving an incidence rate of 4.06 cases per 100 person-years (95% confidence interval: 3.87-4.24). Injection drug use (IDU) was the commonest risk factor among seroconverters, with an HCV incidence rate of 7.08 cases per 100 person-years. Injection drug use history was reported in 83.3% of the seroconverters and in only 47.2% of non-seroconverters; P = 0.005. CONCLUSION: Egyptian HIV-infected patients show a high incidence rate of HCV infection especially among those who have a history of IDU. Accordingly, attention should be paid for prevention, screening and timely treatment of HCV in patients infected with HIV What this study adds: The demonstration of a high HCV infection incidence rate among HIV-infected patients and shows the need for screening and prevention in this population.

ABSTRACT Objective: To describe the clinical-epidemiological characteristics and management of cerebral arteriovenous malformations (AVM) in patients treated at the Instituto Nacional de Salud del Niño San Borja (INSN-SB). Materials and methods: A retrospective and descriptive study conducted in patients with AVM treated at the INSN-SB between 2015 and 2017. Data was processed and analyzed using IBM SPSS Statistics statistical software version 22. The qualitative variables were expressed in absolute and relative frequencies. Results: Forty-one (41) AVM cases were identified, being more frequent in the age group between 6 and 12 years (56.10 %) and in females (65.90 %). Ruptured AVM occurred in 80.49 % of the patients and 92.70 % claimed that headache was the most frequent clinical manifestation. The anatomical areas with the highest occurrence of AVM were the frontal lobe (36.60 %) and the left cerebral hemisphere (51.20 %). Grade III AVM was the most common one (43.90 %) according to the Spetzler-Martin grading scale. The most frequently used treatment was embolization (39 %) and mortality accounted for 2.40 %. Conclusions: AVM most frequently occurred in females and patients between 6 and 12 years old. A little more than half of the patients had a ruptured AVM. Headache was the predominant symptom of this disease. Most patients showed grade III AVM according to the Spetzler-Martin grading scale. Embolization was the most frequently used surgical method and the mortality rate was low.

RESUMEN Objetivo: Describir las características clínico-epidemiológicas y el manejo de las malformaciones arteriovenosas cerebrales (MAVc) en pacientes atendidos en el Instituto Nacional de Salud del Niño San Borja (INSN-SB). Materiales y métodos: Estudio retrospectivo y descriptivo en pacientes con malformaciones arteriovenosas cerebrales atendidos en el Instituto Nacional de Salud del Niño San Borja entre 2015-2017. Los datos fueron procesados y analizados en el programa SPSS versión 22. Las variables cualitativas se expresaron en frecuencias absolutas y relativas. Resultados: Se identificaron 41 malformaciones arteriovenosas cerebrales. La mayoría se presentó en el grupo etario entre los 6 y 12 años (56,10 %) y en el sexo femenino (65,90 %). La ruptura de las malformaciones ocurrió en el 80,49 % de casos, y el 92,70 % de los pacientes tuvo cefalea como manifestación clínica predominante. Las localizaciones más frecuentes fueron el lóbulo frontal (36,60 %) y el hemisferio cerebral izquierdo (51,20 %). El grado más común de las malformaciones arteriovenosas cerebrales fue el III (43,90 %) de la clasificación de Spetzler-Martin. La embolización fue el tratamiento empleado con mayor frecuencia (39 %) y la mortalidad alcanzó el 2,40 %. Conclusiones: Los grupos que presentan malformaciones arteriovenosas cerebrales con mayor frecuencia son las mujeres y los pacientes entre 6 y 12 años. Un poco más de la mitad de los pacientes tuvieron ruptura de la lesión. La cefalea es el síntoma predominante y las malformaciones más frecuentes corresponden al grado III de la escala de Spetzler-Martin. La embolización es el método quirúrgico más empleado y la mortalidad fue baja.

RESUMO O enfrentamento da crise da Covid-19 ressaltou a importância do olhar crítico e sistêmico para a atuação empresarial para sustentabilidade. Este artigo tem como objetivo discutir a sustentabilidade, através das lentes teóricas de sustentabilidade “forte” e “fraca” e suas relações com os paradigmas econômicos; apresentar a teoria da resiliência como alternativa frente aos atuais desafios; e analisar, com base nos conceitos apresentados, indícios de como as organizações estão reagindo inicialmente, em suas atuações com sustentabilidade, à crise da Covid-19. Para tanto, foram realizadas entrevistas semiestruturadas com empresas que atuam no Brasil. Como resultado, indícios de realinhamento ao propósito inicial da empresa de criar valor para a sociedade coexistem com indícios de continuidade da aposta em soluções via mercado e da busca por crescimento infinito em um planeta com recursos limitados.

ABSTRACT Facing up to the COVID-19 crisis has emphasized the importance of taking a critical and systemic look at business action for sustainability. The aims of this article are: to discuss sustainability, through the theoretical lenses of ‘strong’ and ‘weak’ sustainability and its relationship with economic paradigms; to present the theory of resilience as an alternative to the current challenges; and, based on the concepts presented, to analyze the indications of how organizations are reacting to the crisis. To this end, semi-structured interviews were conducted with companies operating in Brazil. As a result it was found that signs of the realignment of the companies’ initial purpose of creating value for society coexist alongside signs of continued investment in market-based solutions and the search for infinite growth on a planet with limited resources.

RESUMEN El enfrentamiento de la crisis de COVID-19 enfatizó la importancia de una visión crítica y sistémica sobre la acción empresarial para la sostenibilidad. Este artículo tiene como objetivo discutir la sostenibilidad, a través de las lentes teóricas de la sostenibilidad ‘fuerte’ y ‘débil’ y sus relaciones con los paradigmas económicos, presentando la teoría de la resiliencia como una alternativa a los desafíos actuales y analizar, a partir de los conceptos presentados, los indicios de cómo las organizaciones están reaccionando a la crisis. Para ello, se realizaron entrevistas semiestructuradas con empresas que operan en Brasil. Como resultado, los signos de realineación con el propósito inicial de la empresa de crear valor para la sociedad coexisten con signos de inversión continua en soluciones basadas en el mercado y de búsqueda de un crecimiento infinito en un planeta con recursos limitados.

BACKGROUND: Knowledge of ear health and hearing loss is essential for early intervention and treatment, but the state of public knowledge of such in Jeddah, Saudi Arabia, remains unknown OBJECTIVES: To measure public knowledge of ear health and hearing loss METHOD: This cross-sectional study was conducted during August 2018 in Jeddah, Saudi Arabia. An electronic survey questionnaire was distributed to 2372 residents of various districts in Jeddah. The survey was created in 2013 by adopting previously published World Health Organization material, designed to assess knowledge and perception of ear health. All males and females aged 10 years or older living in Jeddah had the chance to participate in this study. A total of 2372 people participated. Percentages mean ± standard deviation, one-way analysis of variance (ANOVAs) and independent t-tests were applied to determine the significant difference. p-values of 0.05 or less were considered significant RESULTS: The overall mean number of correct responses on the survey's true/false questionnaire was 10.66 ± 1.92 out of 14. Female participants gave a higher mean number of correct answers than did male participants (10.73 ± 2.03 vs. 10.54 ± 2.03, respectively). Participants with a family history of hearing loss gave a higher mean number of correct answers compared with participants who reported a negative family history (10.89 ± 1.82 vs. 10.53 ± 1.97, respectively CONCLUSION: Overall awareness of ear health and hearing loss management is fair. However, the results indicate a need for more integrated educational materials to be made available both to the general population as well as to hearing loss individuals and their families

Abstract Objective: To examine the prevalence of congenital absence of permanent teeth other than third molar teeth in non-syndromic children in the Black Sea and Mediterranean Regions of Turkey, and the correlation between gender and distribution sites in the jaws. Material and Methods: Panoramic radiographs and clinical records of 9831 children (5025 girls, 4806 boys) in the Mediterranean Region and 11372 children (5540 girls, 5832 boys) in the Black Sea region were examined. All panoramic radiographs were evaluated by a dentist. The permanent tooth, which was not seen in radiography, was recorded as a congenitally missing tooth, and the fact that the tooth was not extracted was confirmed by treatment records. The data were statistically evaluated by Chi-Square and t-test Results: The prevalence of congenitally missing permanent teeth was 2.8% (3.52% in girls, 2.5% in boys) in the Mediterranean region and 1.63% (1.82% in girls and 1.45% in boys) in the Black Sea region. Congenitally missing permanent teeth were observed more in the maxilla compared to mandible. The teeth that most frequently have congenitally missing permanent teeth in the Mediterranean Region are mandibular second premolars, maxillary lateral incisors and maxillary second premolars, respectively. The teeth that most frequently have congenitally missing permanent teeth in the Black Sea region are mandibular second premolars, maxillary second premolars and maxillary lateral incisors, respectively. Most of the patients had one or two teeth missing, and the lack of three or more teeth was rare Conclusion: In this study, which is performed in different climatic characteristics of Black Sea and Mediterranean Regions, the frequency of congenitally missing teeth is similar.

Immunosensors based on impedance spectroscopy for diagnosing hepatitis C are reported where the sensing units were made with the antigenic peptide PPLLESWKDPDYVPPWHG (NS5A-1) derived from the NS5A protein of the hepatitis C virus (HCV) immobilized in layer-by-layer (LbL) films with silk fibroin (SF) and deposited on gold interdigitated electrodes. The electrical response of the sensing units varied upon immersion into solutions containing the antibody anti-HCV owing to the biomolecular recognition of NS5A-1. This was associated with morphological changes on the LbL films caused by adsorption of NS5A-1 and inferred from atomic force microscopy images. Buffer solutions with different anti-HCV concentrations down to 2 ng mL-1 could be clearly distinguished by analyzing the impedance spectroscopy data with a multidimensional projection technique. The specificity toward anti-HCV antibodies was confirmed in control experiments where no significant changes in the electrical response were measured by exposing the sensing units to solutions containing an anti-human immunodeficiency virus (HIV) antibody. The high sensitivity and selectivity of the units made with LbL films demonstrate the feasibility of measuring electrical impedance as an immunosensing strategy to detect hepatitis C.

RESUMO OBJETIVO: Avaliar a evolução da Incidência, mortalidade e custo das urgências abdominais não traumáticas atendidas nos serviços de emergência do Brasil durante o período de nove anos. MÉTODOS: Este trabalho utilizou informações do DataSus de 2008 a 2016, (http://www.tabnet.datasus.gov.br). Foram analisados número de internações, valor médio das internações (AIH), valor total das internações, dias de permanência hospitalar e taxa de mortalidade das seguintes doenças: apendicite aguda, colecistite aguda, pancreatite aguda, diverticulite aguda, úlcera gástrica e duodenal, e doença inflamatória intestinal. RESULTADOS: A doença que teve o maior crescimento do número de internações foi a doença diverticular do intestino, com o valor de 68,2%. Ao longo dos nove anos não houve grandes variações da média de permanência hospitalar, sendo que o maior aumento foi o da úlcera gástrica e duodenal, com crescimento de 15,9%. A taxa de mortalidade da doença por úlcera gástrica e duodenal teve um aumento de 95,63%, consideravelmente significante quando comparada com as outras doenças. Todas tiveram seus valores de AIH aumentados, porém, a que proporcionalmente teve o maior aumento nos últimos nove anos foi a úlcera gástrica e duodenal, com um acréscimo de 85,4%. CONCLUSÃO: As urgências abdominais de origem não traumática são de extrema prevalência, por isso a importância em ter dados atualizados e comparativos sobre a taxa de mortalidade, o número de internações e os custos gerados por essas doenças, para melhor planejamento dos serviços públicos de saúde.

SUMMARY OBJECTIVE: To evaluate the incidence, mortality and cost of non-traumatic abdominal emergencies treated in Brazilian emergency departments. METHODS: This paper used DataSus information from 2008 to 2016 (http://www.tabnet.datasus.gov.br). The number of hospitalizations, costs - AIH length of stay and mortality rates were described in acute appendicitis, acute cholecystitis, acute pancreatitis, acute diverticulitis, gastric and duodenal ulcer, and inflammatory intestinal disease. RESULTS: The disease that had the highest growth in hospitalization was diverticular bowel disease with an increase of 68.2%. For the period of nine years, there were no significant changes in the average length of hospital stay, with the highest increase in gastric and duodenal ulcer with a growth of 15.9%. The mortality rate of gastric and duodenal ulcer disease increased by 95.63%, which is significantly high when compared to the other diseases. All had their costs increased but the one that proportionally had the highest increase in the last nine years was the duodenal and gastric ulcer, with an increase of 85.4%. CONCLUSION: Non-traumatic abdominal emergencies are extremely prevalent. Hence, the importance of having updated and comparative data on the mortality rate, number of hospitalization and cost generated by these diseases to provide better healthcare services in public hospitals.

Resumen Las consecuencias de los desastres naturales en los últimos años han evidenciado la complejidad de esos eventos. Entre las decisiones importantes en situaciones de desastres están la localización de centros de auxilio, la distribución de productos y el dimensionamiento de flota. La ejecución de estas operaciones puede implicar objetivos contradictorios, principalmente, costos logísticos y costos por demanda insatisfecha. Por un lado, minimizar la demanda insatisfecha lleva a mayores costos logísticos. Por otro lado, minimizar los costos logísticos sin considerar la demanda insatisfecha implica un atendimiento ineficaz en las áreas afectadas. En este artículo es desarrollado un modelo biobjetivo de programación estocástica para el problema integrado de localización-distribución y dimensionamiento de flota. Se solucionan instancias basadas en el megadesastre de la región Serrana de Rio de Janeiro en 2011. Las soluciones del modelo biobjetivo son comparadas con una versión mono-objetivo del mismo, resaltando las ventajas y desventajas de cada modelo.

Abstract Consequences of natural disasters in recent years have shown the complexity of these situations. In disaster situations, the location of relief centers, the distribution of supplies and the fleet sizing are some of the most important decisions. In most cases the execution of this operations lead to contradictory objectives, mainly, logistic costs and unmet demand costs. On the one hand, minimize unmet demand implies higher logistics costs. On the other hand, minimize logistics costs without considering the unmet demand may lead with an inefficient attendance in the affected areas. In this paper, we propose a bi-objective stochastic programing model for the integrated problem of location-distribution and fleet sizing. We solve instances based on the mega disaster in the Mountain Region of Rio de Janeiro in 2011. We compare the solutions of a bi-objective model in respect to solutions of a mono-objective version, highlighting the advantages and disadvantages of each model.

Abstract This paper investigates the efficiency of traditional portfolio optimization models when the returns of financial assets are highly volatile, e.g., in financial crises periods. We also develop alternative optimization models that combine the mean absolute deviation (MAD) and the conditional value at risk (CVaR), attempting to mitigate inefficient, low return and/or high-risk, portfolios. Three methodologies for estimating the probability of the asset’s historical returns are also compared. By using historical data on the Brazilian stock market between 2004 and 2013, we analyze the efficiency of the proposed approaches. Our results show that the traditional models provide portfolios with higher returns, but our propose model are able to generate lower risk portfolios, which might be more attractive in volatile markets. In addition, we find that models that do not use equiprobable scenarios produce better results in terms of return and risk.

Resumo Um dos desafios para o planejamento da produção na indústria de nutrição animal consiste em determinar quanto produzir de cada produto em cada período, considerando que existem incertezas associadas às operações de setup, que os produtos são perecíveis e que a capacidade produtiva deve ser ajustada num ambiente de demanda estocástica caracterizada pela sazonalidade dos produtos e das matérias-primas. Este trabalho investiga um problema de planejamento agregado da produção em uma planta que produz suplementos para nutrição animal. Para lidar com esse problema, propôs-se uma extensão do problema clássico de dimensionamento de lotes com restrição de capacidade para incorporar decisões sobre vendas perdidas (lost sales) e as incertezas inerentes ao planejamento da produção: demandas, tempos de preparação e taxa de perecibilidade dos produtos. Para gerar soluções menos sensíveis às variações dos cenários, desenvolveu-se um modelo estocástico com aversão ao risco baseado numa medida de risco do tipo semidesvio absoluto. Analisando-se o valor esperado da informação perfeita e o valor da solução estocástica, confirmou-se o desempenho superior do modelo de programação estocástica no tratamento das incertezas. Além disso, os resultados indicaram que é possível reduzir significativamente a variabilidade dos custos de segundo estágio sem sacrificar demasiadamente o custo total esperado.

Abstract One of the greatest challenges of production planning in the animal nutrition industry is determining the amount of each product that should be produced during each period, given the perishability of the products, the manual execution of the setups and the need to adjust the production capacity in a stochastic demand environment that is characterized by the seasonality of the products and raw materials. This paper investigates an aggregate production planning problem in a plant that produces supplements for horses, cattle, pigs and poultry. To address this problem, we proposed an extension of the classical capacitated lot-sizing problem to incorporate decisions about lost sales and inherent uncertainties in production planning, such as demands, setup times and perishability. To generate solutions that are less sensitive to changes in scenarios, we also developed a risk-averse stochastic model with an absolute semi-deviation-based risk measure. An analysis of the expected value of perfect information and the value of the stochastic solution confirmed that the stochastic approach outperformed the deterministic approximations in handling uncertainty. Furthermore, the results indicated that it is possible to significantly reduce the variability of the second-stage costs without sacrificing the expected total cost.

RESUMOSão Paulo é o Estado no qual clones de seringueira (Hevea brasiliensisWilld. ex Adr. de Juss.) Muell. Arg. têm apresentado maior produtividade de borracha, no Brasil. O objetivo deste estudo foi avaliar a produção de borracha e o vigor de 14 clones de seringueira, implantados na região de Votuporanga, além de averiguar mudanças na tendência da correlação anual, para analisar a possibilidade de uma seleção precoce, com base nos caracteres estudados. Para isso, a produção de borracha, em gramas árvore-1sangria-1, foi avaliada, utilizando-se o sistema de sangria 1/2S d/4 5d/7 11m/y ET 2,5%. O período de avaliação da produção de borracha foi de oito anos. O vigor, também, foi analisado, medindo-se o perímetro do caule por 16 anos. Os clones IRCA 111 e PB 235 tiveram os melhores desempenhos de produção de borracha. Os clones IAC 15 e IAC 44 apresentaram os melhores resultados de vigor. As correlações genéticas e fenotípicas foram significativas e positivas entre todos os anos de produção. Para o vigor, a significância dos coeficientes de correlação genotípica e fenotípica diferiram na pré-sangria e na pós-sangria. Pelos valores de produção de borracha observados, os clones IRCA 111 e PB 235 são considerados favoráveis à recomendação em pequena escala para a região de Votuporanga. Com base nos resultados obtidos, é possível realizar uma seleção precoce para o caráter de produtividade, usando-se os dados obtidos no primeiro ano de avaliação. Por causa das diferenças observadas entre os períodos de pré-sangria e pós-sangria, não é aconselhável realizar uma seleção precoce no período de pré-sangria, visando ao caráter de vigor.

ABSTRACTClones of rubber-tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] have achieved the highest yields of rubber in the State of São Paulo, Brazil. The objective of this study was to evaluate the yield and vigor of 14 rubber-tree clones cultivated in the region of Votuporanga and determine changes in the trend of annual correlation to examine the possibility of an early selection based on the studied characters. The yield of rubber was evaluated in the 1/2S d/4 5d/7 11m/y ET 2,5% tapping system, for a period of eight years. Vigor was also examined by measuring the girth for 16 years. The clones IRCA 111 and PB 235 showed the best yield performance. The best results of vigor, was achieves by clones IAC 15 and IAC 44. Genetic and phenotypic correlations were significant and positive for all production years. The significance of the genotypic and phenotypic correlation coefficients of vigor differed in the pre and post-tapping periods. Considering the rubber production found, the clones IRCA 111 and PB 235 can be recommended for small scale cultivation in the region of Votuporanga. The results showed that is possible to make an early selection for yield character, using the data obtained in the first year of evaluation. Because of the differences found in pre and post-tapping, it is not advisable to make an early selection for vigor in the pre-tapping period.

Esse trabalho aborda um problema de planejamento da produção típico de empresas moveleiras de pequeno porte, em que as demandas e os tempos de preparação dos estágios gargalos são variáveis aleatórias que podem ser aproximadas por um conjunto discreto e finito de cenários ponderados pelas correspondentes probabilidades de ocorrência. O problema com múltiplos cenários é modelado via programação estocástica de dois estágios com recurso. Para controlar a variabilidade dos custos de segundo estágio é proposto um modelo de recurso restrito que gera, progressivamente, um conjunto de soluções menos sensíveis às variações dos cenários, conforme a variabilidade é restringida a uma tolerância dada. Experiências numéricas indicam que, em muitas situações, não é muito dispendioso assegurar soluções aversas ao risco com bons níveis de serviço.

This paper addresses a production planning problem that arises in small-scale furniture companies, where the demands and setup times of bottleneck operations are random variables that can be approximated by a discrete and finite number of scenarios that are weighted by their corresponding probabilities of occurrence. The problem is modeled under multiple scenarios via two-stage stochastic programming with recourse. To control the variability of the second-stage costs, we propose a restricted recourse model that generates a set of solutions that are less sensitive to the scenario changes because the variability is limited to a given tolerance. Numerical experiences indicate that, in some situations, risk-averse solutions with good service levels are not excessively expensive to obtain.

Otimizar problemas de planejamento da produção sob incertezas é um desafio, pois é preciso definir se existe alguma metodologia mais adequada para lidar com o tipo de incerteza do problema, se tal metodologia é computacionalmente tratável e quais as vantagens e desvantagens que as metodologias disponíveis na literatura podem trazer na análise do problema. Neste trabalho, são analisadas duas importantes metodologias para lidar com um problema de planejamento da produção sob incertezas: a programação estocástica de dois estágios e a otimização robusta. Ao passo que a programação estocástica é uma das técnicas mais tradicionalmente utilizadas em problemas de planejamento da produção sob incertezas, a mesma pode gerar modelos intratáveis se o número de cenários for muito grande. A otimização robusta surge como alternativa para superar a aparente limitação dos modelos de programação estocástica, mas ela pode ser muito conservadora, dependendo de como as incertezas são modeladas. As vantagens e desvantagens de cada metodologia são ilustradas com base num problema prático de planejamento da produção de empresas moveleiras e são comparadas em termos de função objetivo, nível de serviço e esforço computacional. Os resultados sugerem que ambas as técnicas são competitivas quando budgets de incerteza menos conservadores são utilizados no modelo de otimização robusta. Verificou-se também que o modelo equivalente robusto pode ser mais fácil de ser resolvido do que a versão estocástica, o que é especialmente importante quando a versão determinística já apresenta dificuldade de resolução.

Optimizing production planning problems under uncertainty is a challenge, because it is necessary to define whether there is a methodology more appropriate to deal with the type of uncertainty of the problem, whether such methodology is computationally tractable, and which advantages and disadvantages the approaches available in the literature can bring to the analysis of the problem. In this paper, we analyze two important methodologies to deal with uncertainties in a production planning problem: two-stage stochastic programming and robust optimization. Whereas stochastic programming is one of the techniques most traditionally used in production planning problems under uncertainty, such approach can generate intractable models when a very large number of scenarios is considered. Robust optimization arises as an alternative technique to overcome the potential drawback of stochastic programming models, but it can be overly conservative depending on how the uncertainties are modeled. This paper also discusses the advantages and disadvantages of each methodology based on a practical problem of production planning in the furniture industry. The comparison between both approaches is given in terms of objective function, service level, and computational effort. The overall results suggest that both techniques are competitive when less conservative budgets of uncertainty are used in the robust optimization model. It was also verified that the robust counterpart model can be more easily solved compared with the stochastic version model, which is especially important when the deterministic model is already difficult to solve.

Os últimos desastres naturais ocorridos no Brasil e no mundo evidenciaram as dificuldades das instituições em fazer uma gestão eficiente de todas as operações necessárias para mitigar a vulnerabilidade das comunidades afetadas. Tais dificuldades são também um reflexo da carência de estudos relacionados ao preparo e à resposta no planejamento de operações de desastres. Nesse contexto, o presente artigo investiga um modelo de otimização de localização-distribuição dentro do paradigma da programação estocástica de dois estágios para melhorar o planejamento das operações de desastres. As decisões de preparo de primeiro estágio estão associadas às localizações dos centros de auxílio, enquanto as decisões de resposta de segundo estágio determinam a distribuição de itens de sobrevivência dos depósitos aos centros de auxílio. O modelo proposto foi analisado com base no megadesastre na região Serrana do Rio de Janeiro em janeiro de 2011.

The recent natural disasters in Brazil and worldwide have highlighted the difficulties of the institutions in managing efficiently all the operations necessary to mitigate the vulnerability of the affected communities. Such difficulties are also a reflection of the lack of studies regarding preparedness and response in disaster operations planning. In this context, this paper investigates a location-distribution optimization model within the two-stage stochastic program paradigm for improving disaster operations planning. The first-stage preparedness decisions are related to the locations of the relief centers, whereas the second-stage response phase determines the distribution of the survival items from the depots to the relief centers. The proposed model was analyzed based on the megadisaster in the Mountain Region of Rio de Janeiro in January 2011.