Problemas de planificación y secuenciación determinística: modelización y técnicas de resolución

Algoritmos originales permiten resolver algunos de los problemas de planificación y secuenciación desde el punto de vista determinístico. Los distintos problemas son clasificados desde el punto de vista de la complejidad computaciona

An inventory system with time-dependent demand and partial backordering under return on inventory investment maximization

Producción CientíficaIn this article, we study an inventory system for items that have a power demand pattern and where shortages are allowed. We suppose that only a fixed proportion of demand during the stock-out period is backordered. The decision variables are the inventory cycle and the ratio between the initial stock and the total quantity demanded throughout the inventory cycle. The objective is to maximize the Return on Inventory Investment (ROII) defined as the ratio of the profit per unit time over the average inventory cost. After analyzing the objective function, the optimal global solutions for all the possible cases of the inventory problem are determined. These optimal policies that maximize the ROII are, in general, different from those that minimize the total inventory cost per unit time. Finally, a numerical sensitivity analysis of the optimal inventory policy with respect to the system input parameters and some useful managerial insights derived from the results are presented.Ministerio de Ciencia, Innovación y Universidades - Fondo Europeo de Desarrollo Regional (project MTM2017-84150-P

Profitability index maximization in an inventory model with a price- and stock-dependent demand rate in a power-form

Producción CientíficaThis paper presents the optimal policy for an inventory model where the demand rate potentially depends on both selling price and stock level. The goal is the maximization of the profitability index, defined as the ratio income/expense. A numerical algorithm is proposed to calculate the optimal selling price. The optimal values for the depletion time, the cycle time, the maximum profitability index, and the lot size are evaluated from the selling price. The solution shows that the inventory must be replenished when the stock is depleted, i.e., the depletion time is always equal to the cycle time. The optimal policy is obtained with a suitable balance between ordering cost and holding cost. A condition that ensures the profitability of the financial investment in the inventory is established from the initial parameters. Profitability thresholds for several parameters, including the scale and the non-centrality parameters, keeping all the others fixed, are evaluated. The model with an isoelastic price-dependent demand is solved as a particular case. In this last model, all the optimal values are given in a closed form, and a sensitivity analysis is performed for several parameters, including the scale parameter. The results are illustrated with numerical examples.Ministerio de Ciencia, Innovación y Universidades y Fondo Europeo de Desarrollo Regional (FEDER) - (project MTM2017-84150-P

Optimal policy for multi-item systems with stochastic demands, backlogged shortages and limited storage capacity

Producción CientíficaIn this paper, an inventory model for multiple products with stochastic demands is developed. The scheduling period or inventory cycle is known and prescribed. Demands are independent random variables and they follow power patterns throughout the inventory cycle. For each product, an aggregate cycle demand is realized first and then the demand is released to the inventory system gradually according to power patterns within a cycle. These demand patterns express different ways of drawing units from inventory and can be a good approach to modelling customer demands in inventory systems. Shortages are allowed and they are fully backlogged. It is assumed that the warehouse where the items are stored has a limited capacity. For this inventory system, we determine the inventory policy that maximizes the expected profit per unit time. An efficient algorithmic approach is proposed to calculate the optimal inventory levels at the beginning of the inventory cycle and to obtain the maximum expected profit per unit time. This inventory model is applicable to on-line sales of a wide variety of products. In this type of sales, customers do not receive the products at the time of purchase, but sellers deliver goods a few days later. Also, this model can be used to represent inventories of products for in-shop sales when the withdrawal of items from the inventory is not at the purchasing time, but occurs in a period after the sale of the products. This inventory model extends various inventory systems studied by other authors. Numerical examples are introduced to illustrate the theoretical results presented in this work.Ministerio de Ciencia, Innovación y Universidades - Fondo Europeo de Desarrollo Regional (project MTM2017-84150-P

Optimization of an inventory system with partial backlogging from a financial investment perspective

Producción CientíficaIn some real inventory systems, item sales can be adjusted to a stable demand rate along the inventory cycle.For instance, home appliances, electrical products, lounge furniture, home water supply, etc., are items with astable demand rate. In this work, we analyze an inventory system for an item of this type, where the demandrate is constant. Shortages are allowed, and it is assumed that a fraction of demand during the stock-outperiod is backlogged. It is supposed that the shortage costs (backorder cost and lost sales cost) have an affinestructure: a fixed cost plus a linear cost that depends on the period of time where shortages exist. In thispaper, instead of the maximization of the profit per unit time, or the minimization of the average inventorycost per unit time, the objective is the maximization of the return on inventory investment, which is a quotientdefined as the average profit divided by the average inventory cost. The optimal inventory policy is obtainedin a closed form under this new perspective. Moreover, it is shown that the optimal policy that maximizes thereturn on inventory investment is, in general, different from the one that maximizes the profit per unit time. Inaddition, the new optimal perspective offers some advantages. The optimal inventory policy that maximizesthe return on investment does not depend on the unit selling price. Therefore, the inventory manager does notneed to change his/her inventory policy if this price changes. These advantages are not usually present whenthe objective is the maximization of the profit per unit time. Numerical examples are provided to illustratethe theoretical results developed in this work. A sensitivity analysis of the optimal policy with respect to thesystem input parameters is also developed.Ministerio de Ciencia, Innovación y Universidades de España y cofinanciado por la Comunidad Europea en el marco del Fondo Europeo de Desarrollo Regional (Research Project MTM2017-84150-P

Excerpta Botanica Pharmaceutica

Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia, Assignatura: Botànica Farmacèutica, Curs: 2013-2014, Coordinadors: Carles Benedí i Joan SimonEl disseny de l’activitat ha estat a càrrec del Grup d’Innovació Docent de Botànica Aplicada a les Ciències Farmacèutiques (GIBAF), i s’emmarca en el Projecte d’Innovació Docent «Excerpta Botanica Pharmaceutica: creació de recursos docents en obert pels propis estudiants com a nova estratègia d’innovació docent» (codi 2014PID-UB/010) del Programa de Millora i Innovació Docent (PMID) de la Universitat de Barcelona.Amb el nom genèric d’Excerpta Botanica Pharmaceutica (extracte de Botànica Farmacèutica), agrupem els treballs (guies d’estudi) que han redactat de forma tutorizada els estudiants del grup T3 de l’assignatura Botànica Farmacèutica (curs 2013-14). Els objectius específics han estat: aprendre a utilitzar correctament la nomenclatura botànica en la denominació de les espècies, saber redactar ordenadament la descripció d’una espècie amb la terminologia botànica adequada, cercar utilitzar i integrar la informació botànica de referència i proposar-ne d’addicional comentades i fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica. Els objectius transversals han estat: estimular el compromís ètic (imatges incloses de llicència lliure), desenvolupar una capacitat de síntesi escrita i de tenir visions globals integradores (la monografia aportada), mantenir una pulcritud en el treball i compromís per la feina ben feta (responsabilitat en el futur material d'ús docent per als seus companys, dipòsit digital UB) i fomentar la apacitat autocrítica (la seva autoavaluació)

Didáctica de la Música Comtemporánea en los Conservatorios de Música

Resumen basado en el de la publicaciónSe incluye archivo con anexosLa formación en arte moderno, muy particularmente en música, resulta muy compleja tanto a nivel primario como secundario. La enseñanza musical se canaliza a través de enseñanzas de régimen general y de régimen especial, formación cultural y formación técnica. Pero en ningún caso la propia legislación apuesta por los valores actuales, sino por la tradición, obviando en buena medida la evolución acaecida en música en los últimos cien años y sus aportaciones. Las principales causas de esta desatención podrían relacionarse con la eficiencia y con la innovación. La actividad docente – en última instancia – viene determinada por el cumplimiento de unas programaciones de amplios contenidos, que requieren una atención muy continuada y que dificultan la ampliación de dichos contenidos con el mismo tiempo de atención. Además, la innovación en contenidos requiere innovación en metodología, así como ampliación de recursos y conocimientos. Aplicar la innovación en términos de eficiencia, requiere del docente un esfuerzo verdaderamente extraordinario de puesta al día en conocimiento de estilos, repertorio, material didáctico (normalmente de difícil acceso, y principalmente editados en el extranjero), grabaciones… y saber adecuarlo a las circunstancias. El proyecto de innovación “Didáctica de la música contemporánea en los conservatorios de música” realizado en el Conservatorio Profesional de Música, C.P.M. “Marcos Redondo" de Ciudad Real, pretende paliar ese déficit de formación en los profesores, que termina por incidir en los alumnos. El hecho de tratarse de un proyecto de innovación supone un incentivo importante para la actividad docente individual, así como para priorizar esta cuestión a nivel de Centro.Consejería de Educación, Cultura y Deportes de Castilla-La ManchaCastilla La ManchaES

Revolution: Museo de las estrellas un paseo por la fama : Hollywood

Convocatoria proyectos de innovación de Extremadura 2020/2021Se describe un proyecto llevado a cabo entre 13 centros educativos extremeños que consistió en desarrollar cinco unidades de trabajo gamificadas, cinco historias detectivescas con misterios por resolver, donde se ponían a prueba las habilidades de lógica, la capacidad de observación, de concentración y de atención de los alumnos. Los objetivos principales de la propuesta fueron: promover la puesta en práctica de proyectos intercentros; impulsar pedagogías activas; desarrollar la competencia digital a través del uso de las pedagogías emergentes lo que ha permitido llevar a cabo una enseñanza presencial, híbrida y virtual y atender a la diversidadExtremaduraES

Head and neck cancer surgery during the COVID-19 pandemic: An international, multicenter, observational cohort study

Background: The aims of this study were to provide data on the safety of head and neck cancer surgery currently being undertaken during the coronavirus disease 2019 (COVID-19) pandemic. Methods: This international, observational cohort study comprised 1137 consecutive patients with head and neck cancer undergoing primary surgery with curative intent in 26 countries. Factors associated with severe pulmonary complications in COVID-19–positive patients and infections in the surgical team were determined by univariate analysis. Results: Among the 1137 patients, the commonest sites were the oral cavity (38%) and the thyroid (21%). For oropharynx and larynx tumors, nonsurgical therapy was favored in most cases. There was evidence of surgical de-escalation of neck management and reconstruction. Overall 30-day mortality was 1.2%. Twenty-nine patients (3%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within 30 days of surgery; 13 of these patients (44.8%) developed severe respiratory complications, and 3.51 (10.3%) died. There were significant correlations with an advanced tumor stage and admission to critical care. Members of the surgical team tested positive within 30 days of surgery in 40 cases (3%). There were significant associations with operations in which the patients also tested positive for SARS-CoV-2 within 30 days, with a high community incidence of SARS-CoV-2, with screened patients, with oral tumor sites, and with tracheostomy. Conclusions: Head and neck cancer surgery in the COVID-19 era appears safe even when surgery is prolonged and complex. The overlap in COVID-19 between patients and members of the surgical team raises the suspicion of failures in cross-infection measures or the use of personal protective equipment. Lay Summary: Head and neck surgery is safe for patients during the coronavirus disease 2019 pandemic even when it is lengthy and complex. This is significant because concerns over patient safety raised in many guidelines appear not to be reflected by outcomes, even for those who have other serious illnesses or require complex reconstructions. Patients subjected to suboptimal or nonstandard treatments should be carefully followed up to optimize their cancer outcomes. The overlap between patients and surgeons testing positive for severe acute respiratory syndrome coronavirus 2 is notable and emphasizes the need for fastidious cross-infection controls and effective personal protective equipment