169 research outputs found

    Review of fuzzy techniques in maritime shipping operations

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    A GRASP-Tabu Heuristic Approach to Territory Design for Pickup and Delivery Operations for Large-Scale Instances

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    Weaddressalogisticsdistrictingproblemfacedbyaparcelcompanywhoseoperationsconsistofpickingupanddeliveringpackages overaserviceregion.Thedistrictingprocessaimstofindapartitionoftheserviceregionintodeliveryandcollectionzonesthat may be served by a single vehicle that departs from a central depot. Criteria to be optimized are to balance workload content among the districts and to create districts of compact shape. A solution approach based on a hybrid procedure that combines elements of GRASP and Tabu Search (TS) is proposed to solve large-scale instances. Numerical experimentation is performed consideringdifferentinstancesizesandtypes.Resultsshowthattheproposedsolutionapproachisabletosolvelarge-scaleinstances inreasonablecomputationaltimeswithgoodqualityofthesolutionsobtained.Todeterminethequalityofthesolutions,resultsare comparedwithCPLEXsolutionsandwiththecurrentrealsolutiontohighlightthebenefitsoftheproposedapproach.Conclusions andrecommendationsforfurtherresearchareprovided

    A GRASP-Tabu Heuristic Approach to Territory Design for Pickup and Delivery Operations for Large-Scale Instances

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    We address a logistics districting problem faced by a parcel company whose operations consist of picking up and delivering packages over a service region. The districting process aims to find a partition of the service region into delivery and collection zones that may be served by a single vehicle that departs from a central depot. Criteria to be optimized are to balance workload content among the districts and to create districts of compact shape. A solution approach based on a hybrid procedure that combines elements of GRASP and Tabu Search (TS) is proposed to solve large-scale instances. Numerical experimentation is performed considering different instance sizes and types. Results show that the proposed solution approach is able to solve large-scale instances in reasonable computational times with good quality of the solutions obtained. To determine the quality of the solutions, results are compared with CPLEX solutions and with the current real solution to highlight the benefits of the proposed approach. Conclusions and recommendations for further research are provided

    Respuesta inmune post vacunación para la hepatitis B y tuberculosis en niños de 10 años. Consolación del Sur / Immune response after vaccination for hepatitis B and tuberculosis in children under 10, Consolación del Sur

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    En Cuba, el control de las enfermedades infecciosas constituye una de las estrategias priorizadas del Ministerio de Salud Pública, y en aquellas que para su prevención y erradicación existen vacunas con eficacia y calidad probada, de manera sistemática se orienta conocer su inmunogenicidad mediante estudios longitudinales e intervencionales. En este estudio se incluyeron la antihepatitis B y el BCG; ambas vacunas forman parte del Programa Nacional de Inmunización. Se evaluó la respuesta celular mediante método Inmunoenzimático (ELISA) para la antihepatitis B y observación de la huella para el BCG, a 498 niños de 10 años nacidos en el año 1994, pertenecientes al municipio Consolación del Sur, en la provincia de Pinar del Río, que habían recibido el esquema propuesto para ambas vacunas en la infancia. Se determinó que existió asociación en la respuesta inmune para ambas vacunas pasados 10 años de aplicadas. El normo peso al nacer tuvo un efecto protector para la respuesta inmune del BCG; sin embargo, para la antihepatitis B y el bajo peso al nacer se observó una alta significación estadística en aquellos que no alcanzaron valores de Seroprotección. No obstante, se comprobó la calidad de las vacunas estudiadas, evidenciado por la ausencia de marcadores de infección para ambas enfermedades. Palabras Clave: Enfermedades infecciosas/ epidemiología; bcg y antihepatitis b/ vacunas; respuesta inmune/ inmunología; programa nacional de inmunización/ prevención y control ABSTRACT Controlling infectious deseases constitutes one of the top priorities of the Ministry of Public Health in Cuba, and in those diseases that there is an efficient vaccine for prevention and complete elimination, knowing its immunogenicity is oriented by means of interventionist and lifetime research. In this study both, antihepatitis B and BCG were included, constituting also part of the National Program of Immunization. In this study, the cell response was evaluated by means of the inmunoenzimatic method (ELISA) for antihepatitis B, and the observation of scar or trace for BCG in 498 children born in 1994 and living in Consolación del Sur, Pinar del Río province, that had previously received a scheme for both vaccines during their chilhood. Associations in immune responses for both vaccines were determined after 10 years. Newborn with normal weight had a protection effect for BCG immune response, however, for antihepatitis B and low weight newborn, a high statistical significance was observed in those that did not get Seroprotection levels. Despite of this, the quality of the vaccines was proved, evidenced by the absence of infection markers for both diseases.Key Words: Infectious deseases/ epidemiology; bcg and antihepatitis b/ vaccines; immune response/ immunology; national program of immunization/ prevention and control

    Respuesta inmune post vacunación para la hepatitis B y tuberculosis en niños de 10 años. Consolación del Sur / Immune response after vaccination for hepatitis B and tuberculosis in children under 10, Consolación del Sur

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    En Cuba, el control de las enfermedades infecciosas constituye una de las estrategias priorizadas del Ministerio de Salud Pública, y en aquellas que para su prevención y erradicación existen vacunas con eficacia y calidad probada, de manera sistemática se orienta conocer su inmunogenicidad mediante estudios longitudinales e intervencionales. En este estudio se incluyeron la antihepatitis B y el BCG; ambas vacunas forman parte del Programa Nacional de Inmunización. Se evaluó la respuesta celular mediante método Inmunoenzimático (ELISA) para la antihepatitis B y observación de la huella para el BCG, a 498 niños de 10 años nacidos en el año 1994, pertenecientes al municipio Consolación del Sur, en la provincia de Pinar del Río, que habían recibido el esquema propuesto para ambas vacunas en la infancia. Se determinó que existió asociación en la respuesta inmune para ambas vacunas pasados 10 años de aplicadas. El normo peso al nacer tuvo un efecto protector para la respuesta inmune del BCG; sin embargo, para la antihepatitis B y el bajo peso al nacer se observó una alta significación estadística en aquellos que no alcanzaron valores de Seroprotección. No obstante, se comprobó la calidad de las vacunas estudiadas, evidenciado por la ausencia de marcadores de infección para ambas enfermedades. Palabras Clave: Enfermedades infecciosas/ epidemiología; bcg y antihepatitis b/ vacunas; respuesta inmune/ inmunología; programa nacional de inmunización/ prevención y control ABSTRACT Controlling infectious deseases constitutes one of the top priorities of the Ministry of Public Health in Cuba, and in those diseases that there is an efficient vaccine for prevention and complete elimination, knowing its immunogenicity is oriented by means of interventionist and lifetime research. In this study both, antihepatitis B and BCG were included, constituting also part of the National Program of Immunization. In this study, the cell response was evaluated by means of the inmunoenzimatic method (ELISA) for antihepatitis B, and the observation of scar or trace for BCG in 498 children born in 1994 and living in Consolación del Sur, Pinar del Río province, that had previously received a scheme for both vaccines during their chilhood. Associations in immune responses for both vaccines were determined after 10 years. Newborn with normal weight had a protection effect for BCG immune response, however, for antihepatitis B and low weight newborn, a high statistical significance was observed in those that did not get Seroprotection levels. Despite of this, the quality of the vaccines was proved, evidenced by the absence of infection markers for both diseases.Key Words: Infectious deseases/ epidemiology; bcg and antihepatitis b/ vaccines; immune response/ immunology; national program of immunization/ prevention and control

    Durabilidad de la respuesta inmune contra el VHB en niños y madres portadoras, Consolación del Sur / Duration of immune response against VHB in carrier children and mothers, Consolación del Sur

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    El Ministerio de Salud Pública de Cuba se ha propuesto la eliminación de la hepatitis viral tipo B para cumplir con este objetivo se lleva a cabo un Programa Nacional que comenzó en 1991 con la vacunación de los niños nacidos de madres portadoras de hepatitis B, y posteriormente se amplió a todos los recién nacidos a partir de 1992. Uno de los parámetros para evaluar la inmunogenicidad de una vacuna es la durabilidad de la respuesta post vacunal, que permite demostrar además la necesidad o no de una dosis de refuerzo. Tomando en consideración este tipo de estudio, se realizó la cuantificación de los niveles de títulos de anticuerpos contra el VHB (Anti-HBsAg) en niños de 10 años nacidos en el año 1994 pertenecientes a Centros Escolares del Municipio Consolación el Sur en la provincia de Pinar el Río, así como madres portadoras del VHB y sus hijos cuyos nacimientos ocurrieron en igual período. Las muestras serológicas se evaluaron mediante el método inmunoenzimático ( ELISA ) para el sistema HBsAg- anti HBsAg obtenido en el Departamento de Inmunología del Instituto Superior de Ciencias Médicas y utilizado en el Centro Nacional de Genética Médica. En aquellos individuos que resultaron negativos para el HBsAg y con títulos de Anti-HBsAg < 10 UI/L se les aplicó una dosis refuerzo evidenciándose respuesta secundaria de memoria en el 100% de los estudiados. Palabras clave: Salud pública, hepatitis b/prevención y control/inmunología / patología, Programas nacionales de salud, Anticuerpos / inmunología, Vacunas, Sangre. ABSTRACT The Ministry of Public Health in Cuba has set as one of its goals the total elimination of Hepatitis B, and to fulfill this objective, a national program is carried out which started with the vaccination program of children born from hepatitis B carrier mothers back in 1991, covering later all newborn babies in 1992. One of the parameters to evaluate immunogenicity in a vaccine is its post vaccine everlasting response that shows the need or not of a back up dose. Taking into consideration this research, a quantitation of antibody levels against Hepatitis B was done (Anti-HBsAg) in 10 year old children born in 1994, belonging to school centers in Consolacion del Sur, Pinar del Río province, as well as Hepatitis B carrier mothers and their children whose births occured in the same period. The serological samples were evaluated by means of the immunoenzimatic method (ELISA), obtained in the Higher Institute of Medical Sciences and used in the Department of Hepatitis B of the National Center of Medical Genetics. In those individuals who tested negative for HBsAg and with titles of Anti-HBsAg< 10UI/L, a booster was applied and the immunological memory response was evidenced in a 100% of the researched children. Key words: Public health, hepatitis b/prevention and control/immunology/pathology, national health programs, antibodies/immunology, vaccines, blood

    Semi-Huber quadratic function and comparative study of some MRFs for Bayesian image restoration

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    The present work introduces an alternative method to deal with digital image restoration into a Bayesian framework, particularly, the use of a new half-quadratic function is proposed which performance is satisfactory compared with respect to some other functions in existing literature. The bayesian methodology is based on the prior knowledge of some information that allows an efficient modelling of the image acquisition process. The edge preservation of objects into the image while smoothing noise is necessary in an adequate model. Thus, we use a convexity criteria given by a semi-Huber function to obtain adequate weighting of the cost functions (half-quadratic) to be minimized. The principal objective when using Bayesian methods based on the Markov Random Fields (MRF) in the context of image processing is to eliminate those effects caused by the excessive smoothness on the reconstruction process of image which are rich in contours or edges. A comparison between the new introduced scheme and other three existing schemes, for the cases of noise filtering and image deblurring, is presented. This collection of implemented methods is inspired of course on the use of MRFs such as the semi-Huber, the generalized Gaussian, the Welch, and Tukey potential functions with granularity control. The obtained results showed a satisfactory performance and the effectiveness of the proposed estimator with respect to other three estimators
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