Setting the Processing Parameters in Injection Molding through Multiple Criteria Optimization: A Case Study

Abstract-In this work, a case study involving statistical characterization and multiple criteria optimization on injection molding is presented. This case study is the first application of a method previously described in the literature involving Data Envelopment Analysis geared towards setting design and process variables to meet several performance measures

Optimal Cement Mixtures Containing Mineral Admixtures under Multiple and Conflicting Criteria

In modern construction industry, fabrication of sustainable concrete has turned the decision-making process into a challenging endeavor. One alternative is using fly ash and nanostructured silica as cement replacements. In these modern mixtures, proper concrete bulk density, percentage of voids, and compressive strength normally cannot be optimized individually. Hereby, a decision-making strategy on the replacement of those components is presented while taking into account those three performance measurements. The relationships among those components upon concrete fabrication required a design of experiments of mixtures to characterize those mineral admixtures. This approach integrates different objective functions that are in conflict and obtains the best compromise mixtures for the performance measures being considered. This optimization strategy permitted to recommend the combined use of fly ash and nanosilica to improve the concrete properties at its early age

3D Printed hydroponic system

Hydroponic systems have been around for many years and there is a large variety of designs. This project approaches the design of a stackable hydroponic system for domestic use aiming for high yield. The 3-D printed prototype consisted of cylindrical elements each with three entries for seeding. These elements can be stacked up and rotated around one another providing configuration flexibility. In addition, the cap of our system is a half cylindrical element. A preliminary test included the use of Rockwool to grow coriander for 14 days. Being a prototype, it is still necessary to optimize the design, fine-tune its operation beyond its initial feasibility to both, maximize yield and minimize cost, which implies compromising on these two conflicting objectives.Los sistemas hidropónicos existen desde hace ya varios años en una amplia variedad de diseños y configuraciones. El proyecto que aquí se describe comprende el diseño de un sistema hidropónico modular apilable para uso doméstico, con miras a que sea uno con alta productividad. Una impresora 3D se utilizó para desarrollar el prototipo que consta de elementos cilíndricos, cada uno con tres receptáculos. A los elementos cilíndricos apilables se les puede rotar con respecto de su eje, añadiendo así mayor flexibilidad de configuración. Convenientemente, la tapa del sistema está formada por medio elemento cilíndrico. Para la prueba preliminar que aquí se describe, se depositaron semillas de cilantro por un período de 14 días en Rockwool. En su fase prototípica, se determinó la factibilidad del sistema, aunque se reconoce que es aún necesario optimizar el diseño y afinar su operación. Esto implicará conciliar dos objetivos en conflicto: maximizar la productividad del sistema y minimizar su costo total

Balance de 25 años de jurisprudencia de la Corte Constitucional

La Corte Constitucional de Colombia ha tenido un importante impacto en la vida social, cultural y política del país, a tal punto que, desde su creación, la jurisprudencia de este tribunal se ha convertido en un referente mundial acerca de las diversas materias sobre las que se ha pronunciado . Este libro presenta un balance de la jurisprudencia que durante sus primeros veinticinco años la Corte ha expedido. Con este fin, el magistrado Luis Guillermo Guerrero Pérez y los magistrados auxiliares Miguel Polo Rosero y Claudia Escobar García recogen los trabajos de expertos nacionales e internacionales, funcionarios del Estado y Miembros de la sociedad civil que se presentaron en el XII Encuentro de la Jurisdicción Constitucional, realizado en la ciudad de San Juan de Pasto entre el 27 y el 30 de septiembre de 2017. En ese encuentro, se ratificó que la Corte Constitucional tiene la tarea de velar por la integridad de los compromisos de la Constitución. Los capítulos que conforman este libro ofrecen una mirada multidisciplinaria sobre la eficacia y el impacto de las decisiones de la Corte, específicamente en lo que tiene que ver con la democracia y la participación, el sistema de salud, el sistema pensional, el medio ambiente y el fenómeno discriminatorio con la relación al género y a la condición de discapacidad en Colombia.Bogot

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Agrupamiento de datos para la solución del problema de optimización multicriterio

En la industria de la manufactura la gran mayoría de las veces se buscan satisfacer objetivos múltiples que, en general, muestran diferentes grados de conflicto entre ellos. La importancia de la solución efectiva de este tipo de problemas es evidente. Por esta razón, en este trabajo se presenta el estudio de diferentes esquemas para el agrupamiento de datos, que hacen más eficiente el uso de Análisis envolvente de datos (AED) para resolver problemas reales de optimización de criterios múltiples. Los resultados de este estudio apuntan favorablemente a la adopción de los esquemas de agrupamiento en aplicaciones reales

Toma de decisiones en la vida diaria bajo dos criterios cuantificables

En la vida diaria existen situaciones en las que tomar una decisión se complica debido a la presencia de conflicto entre múltiples criterios de desempeño