Prácticas de gestión tecnológica en la industria de la construcción: el caso de una empresa pública de ingeniería civil

En la actualidad, las empresas que quieren crecer tienen que desarrollar nuevos y mejores productos o servicios. Una forma de lograrlo es a través de la gestión tecnológica. En México existe un premio nacional que se otorga a las compañías que cuentan con sistemas eficientes de gestión que las hacen ser más competitivas. Dicho galardón lo han ganado organizaciones privadas en diversos sectores como los de telecomunicaciones, electrodomésticos y farmacéuticos. Sin embargo, las instituciones públicas y en particular las de la industria de la construcción no han recibido esa distinción. En un esfuerzo por determinar los niveles de uso y de importancia percibida de las "mejores prácticas" de gestión tecnológica en una empresa del gobierno dedicada a la ingeniería civil, se llevó a cabo una investigación. Los resultados revelan que aún existen oportunidades de mejora en el secto

Life-Cycle Cost of Bridges on Seismic Zones for Risk Management

In this paper the acceptable failure probability and the risk of important bridges, located on seismic zones, are calculated throughout the expected cost of failure consequences. Also, the bridge expected life-cycle cost is formulated in terms of the bridge seismic hazard and the potential consequences of failure. These consequences include aspects arising from the physical loss of the bridge to the human casualties and economical cost of the loss of service, which are estimated in monetary terms. Current codes do not explicitly deal with this issue and in practice subjective estimations from experience are considered for some general cases. Bridge reliability is an essential component of risk and in this paper is estimated in a simplified way and applied to the structural types given in the examples. Monte Carlo simulation techniques are used to explicitly account for the uncertainties. Initial and failure cost curves are determined for all possible seismic intensities and expected life-cycle costs conditional to these intensities are obtained. The unconditional expected lifecycle cost is calculated by convolution of the conditional costs by the occurrence probabilities of these intensities, which are obtained from the seismic hazard curve of the given site. The procedure is illustrated throughout three reinforced concrete bridges located 1 on the soft soil of Mexico City and the other two on other sites with less seismic activity and different traffic volumes. The results may be extended to get risk management policies for bridges and to improve the current Mexican codes and to enhance the practices on bridge design and maintenance on seismic zones

Manejo sustentable del sitio en proyectos de arquitectura; criterios y estrategias de diseño

El presente trabajo consta del estudio y revisión de estrategias de diseño sustentable para el manejo del sitio de proyectos de arquitectura y de cómo podemos aprovechar de una mejor manera el entorno para beneficiar tanto al proyecto arquitectónico como al contexto urbano. El trabajo consta particularmente de recomendaciones de diseño arquitectónico sustentable para hacer una mejor selección y planeación del sitio, así como una mejor orientación y ubicación del edificio en el sitio; también se proponen conceptos generales para el manejo y cuidado del paisaje del sitio del proyecto, respetando los recursos naturales del lugar como aprovechamiento de agua, energía, disminución de islas de calor, aprovechamiento de materiales de construcción y aprovechamiento de los recursos bióticos y abióticos del lugar.El presente trabajo consta del estudio y revisión de estrategias de diseño sustentable para el manejo del sitio de proyectos de arquitectura y de cómo podemos aprovechar de una mejor manera el entorno para beneficiar tanto al proyecto arquitectónico como al contexto urbano. El trabajo consta particularmente de recomendaciones de diseño arquitectónico sustentable para hacer una mejor selección y planeación del sitio, así como una mejor orientación y ubicación del edificio en el sitio; también se proponen conceptos generales para el manejo y cuidado del paisaje del sitio del proyecto, respetando los recursos naturales del lugar como aprovechamiento de agua, energía, disminución de islas de calor, aprovechamiento de materiales de construcción y aprovechamiento de los recursos bióticos y abióticos del lugar

Práctica de la Gestión de proyectos en la industria de la construcción: un caso en el Estado de México (parte II)

El sector de la construcción contribuye sustancialmente al desarrollo de un país en virtud de que genera la infraestructura requerida por la sociedad para mejorar su calidad de vida. Esto pone de manifiesto la necesidad de diseñar herramientas para que los profesionales del ramo puedan administrar adecuadamente sus proyectos. Los libros y artículos hasta ahora escritos reportan distintas técnicas teóricas, pero son pocos los casos de estudio en los que se ilustra la aplicación de ellas. Esta situación impide que los practicantes tengan ejemplos útiles que les ayuden a implementar nuevas ideas para mejorar los procesos internos de sus compañías. En un esfuerzo por generar conocimiento en este sentido, se ha llevado a cabo un estudio en una empresa del Estado de México, tomando un ejemplo un proyecto sanitario en el cual se aplicaron empíricamente algunas herramientas teóricas de la gestión de proyectos

Woody debris trapping phenomena evaluation in bridge piers: A Bayesian perspective

l artículo propone el uso de una red bayesiana y analiza sus ventajas y desventajas para realizar el diagnóstico y la propuesta de remediación en el caso de puentes sujetos a la acumulación de escombros de madera en la base de las pilas.A flood occurs when water and other materials such as woody debris overflow dry areas. If there is infrastructure present, woody fragments could be transported downstream and eventually trapped, leading to increments in the hydrodynamic forces over, say, a bridge. Moreover, local scour can be developed in the structure piers. The purpose of this research is to investigate the bridge pier scour phenomena induced by woody debris from a probabilistic point of view. A Non Parametric Bayesian Belief Network comprising seven nodes has consequently been developed. They are: water level, Froude number, blockage amount, drag force, scour depth, damage and overturning. Through both Monte Carlo Simulation and data from a real structure, the nodes’ non parametric probability distributions have been established, an area that has, to date, received very little attention in the literature. By combining the variables under study, it was possible to determine their interaction and dependencies, showing that the depth of the approaching flow is correlated with two nodes: damage and overturning. The results are useful for bridge managers willing to rank investments in maintenance actions within the industry, and to develop optimal risk based strategies for efficiently employing the scarce resources used to that end

Biomimicry: natural systems in situ analysis aimed to rain water harvesting

Population growth has put a considerable pressure upon Mexico’s water supply, diminishing it in some regions of the country. The study of Biomimicry has less than 15 years of study, as a discipline aimed to analyses and study natural systems to emulate its characteristics and translate them into designs that can solve needs in a sustainable way. Using the latter to solve the former, it can be said that a possible way to harvest water from the environment to help the water supply; is using as inspiration of the way in which some plants native from Mexico’s dry regions obtain water from the environment in an efficient manner. This is possible since these plants have evolved to extract water micro particles and keep them in their inner reservoirs.Water is a valuable natural resource for life, but the poor management is making it scarce. This lack of care has created a series of social and technical problems, including the difficulties to distribute it to individual homes, particularly in Mexico. In order to solve such problems, it is necessary to find alternatives for its harvesting, care, distribution and use; allowing to reduce social stress, as well as allowing for a better water stewardship. One option is using Biomimicry and design as tools to find innovative, sustainable solutions. The conclusions of this current research project show how two different Mexican plants of notable importance, in economic and even gastronomical terms, had been analyzed through the eyes of the Biomimicry in order to extrapolate possible solutions of water harvesting and distribution. The aim of this paper is to discuss the results of such analyses

Obtención de un índice de sustentabilidad aplicado a materiales de construcción

Este artículo aplica dos conceptos con la finalidad de obtener un índice de sustentabilidad para edificaciones. El primero se refiere al análisis del ciclo de vida de materiales de construcción, evaluado con parámetros como el calentamiento global, partículas cancerígenas y no cancerígenas, contaminantes del aire, eutrofización, ecotoxicidad, smog, el agotamiento de los recursos naturales, calidad del aire interior, y el agotamiento de la capa de ozono. El segundo concepto es la aplicación de Sistemas de Inferencia Borrosa (Fuzzy Inference Systems, FIS) el cual es un modelo que intenta emular el proceso de razonamiento de un experto en el área de construcciones y medio ambiente, a través del cual se calcula un índice sobre la sustentabilidad de los materiales utilizados en un edificio, que toma en cuenta el ciclo de vida de los mismos. Dichos materiales han sido previamente analizados mediante el programa computacional SimaPro, un software de evaluación de ciclo de vida que considera variables consensadas internacionalmente

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p<0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (<1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (<1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements