Estudio de alternativas para la red de saneamiento de aguas residuales de la ciudad de San Benito, Nicaragua

[ES] El presente trabajo desarrolla el diseño de la red de saneamiento de aguas residuales en la ciudad de San Benito, en Nicaragua. Mediante el análisis de la población y el área de estudio como principales condicionantes, se plantean diferentes alternativas para la ubicación de la planta depuradora. Una vez definida la ubicación, se plantean dos posibles trazados para los principales colectores. La elección de la red a diseñar se realiza mediante el estudio de las alternativas, incluyendo la valoración técnica, ambiental y económica de los trazados principales de acuerdo con las normativas y criterios técnicos de aplicación en Nicaragua. El trabajo incluye los trabajos de topografía, geología, censo y encuestas; adicionalmente se recoge información climatológica del área de estudio y de la situación actual de los sistemas de abastecimiento y saneamiento, y se completa la caracterización urbanística de la ciudad. Por último, con la elección de la alternativa más adecuada se procede a diseñar la totalidad de la red de saneamiento, incluyendo la elaboración del presupuesto y los planos. El documento contendrá, al menos, los siguientes documentos. Memoria y anejos 1. Objeto y alcance 2. Antecedentes - Caracterización y descripción de la zona de estudio - Climatología - Caracterización y descripción urbanística - Delimitación del área de estudio - Evaluación física de la infraestructura existente - Situación del abastecimiento y saneamiento - Problemática actual 3. Topografía 4. Geología y geotecnia 5. Estudio y proyección de la población - Análisis de la tasa de crecimiento - Proyección de la población 6. Estudio de la demanda 7. Diagnóstico de la situación actual 8. Evaluación de las posibles ubicaciones de la PTAR 9. Estudio de las alternativas de la red de saneamiento - Evaluación técnica - Evaluación económica - Evaluación ambiental - Comparación y elección 10. Diseño de la red de saneamiento Presupuesto PlanosGórriz Redón, M. (2020). Estudio de alternativas para la red de saneamiento de aguas residuales de la ciudad de San Benito, Nicaragua. http://hdl.handle.net/10251/150544TFG

A spatio-temporal multinomial model of firearm death in Ecuador

This paper presents a statistical model based on a multinomial distribution with fixed and random effects, the latter effects being structured and non-structured in space and time. Inference is performed through a Bayesian framework. We are interested in analyzing violent deaths at the level of parroquia in Ecuador. Noting that most of the deaths are linked to firearms, and much less with knifes, we build a multinomial model to predict the probability of three different types of deaths as a close proxy to a violent death having had occurred. We provide a practical and realistic interpretation of the model putting this in the real crime context and scenario in Ecuador

Influence of glycerin and lecithin inclusion in the diet on liver characteristics and lipid fraction in the serum of brownegg laying hens at 55 week of age

The effects of the inclusion of raw glycerin (GLYC) and raw lecithin, in the diet (23 to 55 wk) on liver characteristics and various serum lipid fractions were studied in brown egg-laying hens at 55 wk of age. The control diets were based on corn, soybean meal, and 4% supplemental fat and contained 2,750 kcal AMEn/kg, 16.5% CP, and 0.73% digestible Lys. The diets were arranged as a 2 × 3 factorial with 2 levels of GLYC (0 and 7%) and 3 animal fat to lecithin ratios (4:0, 2:2, and 0:4%). Each treatment was replicated 8 times and the experimental unit was a cage with 10 hens. At 55 wk of age, 2 hens per cage replicate were randomly selected, weighed individually, and slaughtered by CO2 inhalation. Liver was immediately removed and weighed and the color recorded by spectrophotometry. In addition, blood samples from one bird per replicate were collected from the wing vein and the concentration of total cholesterol, low and high density lipoprotein cholesterol, and triglycerides were determined. The data were analyzed as a completely randomized design and the main effects of GLYC and lecithin content of the diet and the interactions were determined. No interactions between GLYC and lecithin content of the diets were detected for any of the variables studied. Liver characteristics and serum lipid traits were not affected by the inclusion of GLYC in the diet. The substitution of animal fat by lecithin, however, reduced the redness (a* 14.9 to 13.8) and yellowness (b* 8.60 to 7.20) values of the liver (P < 0.05) but did not affect the content of serum lipid fractions. It is concluded that the inclusion of GLYC and lecithin in the diet did not affect liver size or serum lipid fraction. However, the inclusion of lecithin reduced the a* and b* value of the live

Thermally modified (TM) beech wood: compression properties, fracture toughness and cohesive law in mode II obtained from the three-point end-notched flexure (3ENF) test

[EN] The fracture properties of thermally modified beech (Fagus sylvatica) wood (TMW) at 180 degrees and 200 degrees C were evaluated in mode II using the three-point end-notched flexure (3ENF) scheme assisted by three-dimensional (3D) stereovision equipment for obtaining displacements and strains. The compliance-based beam method (CBBM) provided the strain energy release rates (G(II)) of TMW and cohesive laws for both native wood (W) and TMW. Based on the CBBM and equivalent crack length approach (ECLA), G(II) was obtained directly from the force-deflection data. The thermal modification (TM) process reduced the compressive strength by 4.4% and increased the compressive elastic modulus by 38.3%, whereas G(II) was reduced substantially by 40.8% and 67.9% at TM180 degrees C and TM200 degrees C, respectively. TM also increased wood brittleness that was visible on the displacement slip reduction. The resulting mean cohesive models can be used for numerical analyses. The fracture properties of TMW have to be taken into consideration for constructional wood application, when cyclic loading may lead to microcracking and material fatigue.The authors would like to thank COST Action FP1407 (Funder Id: https://dx.doi.org/10.13039/501100000921), the European Commission for funding the InnoRenew CoE project under the Horizon2020 Widespread-Teaming program (grant agreement #739574), the Republic of Slovenia for providing support from the European Regional Development Funds, and the financial support provided by the Internal Grant Agency (IGA) of the Faculty of Forestry and Wood Technology, Mendel University in Brno (LDF_PSV_2016015).Sebera, V.; Redón-Santafé, M.; Brabec, M.; Decky, D.; Cermak, P.; Tippner, J.; Milch, J. (2019). Thermally modified (TM) beech wood: compression properties, fracture toughness and cohesive law in mode II obtained from the three-point end-notched flexure (3ENF) test. Holzforschung. 73(7):663-672. https://doi.org/10.1515/hf-2018-018866367273

Analysis and optimization of subcritical two-stage vapor injection heat pump systems

Two of the major problems of heat pump systems working in extreme conditions are the loss of efficiency of the system and the high compressor discharge temperatures. One possibility in order to overcome these issues is to perform the compression in two stages. In this frame the use of vapor injection two stage cycles represent an economic and effective solution. This study analyzes the influence of design parameters and injection conditions for two different configurations of two stage cycles, for four refrigerants (R407C, R290, R22 and R32). Design parameters, such as the displacement ratio, are optimized in terms of COP in ideal conditions for both injection systems. A deeper analysis taking into account the efficiencies of the compressor is done finding that two stage systems could reach improvements of 30% in terms of COP compared with one stage systems and that a bad design of this type of systems could represent a loss of improvement between 6% and 10%. Finally a method to control the system at any operating point in order to make it works in its optimum is done. From all the analysis, guidelines for the optimum design and control of such systems are obtained in terms of capacity, Coefficient of Performance (COP), seasonal performance factor and discharge temperature criteria.This work has been partially supported by the Spanish Ministerio de Economia y Competitividad through the project rsf. DPI 2011-26771-C02-01. The authors are grateful for the given support.Redon Climent, A.; Navarro Peris, E.; Pitarch, M.; Gonzálvez Maciá, J.; Corberán Salvador, JM. (2014). Analysis and optimization of subcritical two-stage vapor injection heat pump systems. Applied Energy. 124:231-240. doi:10.1016/j.apenergy.2014.02.066S23124012

IMPLEMENTATION OF A PHOTOVOLTAIC FLOATING COVER FOR IRRIGATION RESERVOIRS

[EN] The article presents the main features of a floating photovoltaic cover system (FPCS) for water irrigation reservoirs whose purpose is to reduce the evaporation of water while generating electrical power. The system consists of polyethylene floating modules which are able to adapt to varying reservoir water levels by means of tension bars and elastic fasteners. (C) 2013 Elsevier Ltd. All rights reserved.Redón-Santafé, M.; Ferrer-Gisbert, P.; Sánchez-Romero, F.; Torregrosa Soler, JB.; Ferran Gozalvez, JJ.; Ferrer Gisbert, CM. (2014). IMPLEMENTATION OF A PHOTOVOLTAIC FLOATING COVER FOR IRRIGATION RESERVOIRS. Journal of Cleaner Production. 66:568-570. doi:10.1016/j.jclepro.2013.11.006S5685706

Use of floating PV plants for coordinated operation with hydropower plants: Case study of the hydroelectric plants of the Sao Francisco River basin

[EN] In recent years, the Brazilian electricity sector has seen a considerable reduction in hydroelectric production and an increase in dependence on the complementation of thermoelectric power plants to meet the energy demand. This issue has led to an increase in greenhouse gas emissions, which has intensified climate change and modified rainfall regimes in several regions of the country, as well as increased the cost of energy. The use of floating PV plants in coordinated operation with hydroelectric plants can establish a mutual compensation between these sources and replace a large portion of the energy that comes from thermal sources, thereby reducing the dependence on thermoelectric energy for hydropower complementation. Thus, this paper presents a procedure for technically and economically sizing floating PV plants for coordinated operation with hydroelectric plants. A case study focused on the hydroelectric plants of the Sao Francisco River basin, where there has been intense droughts and increased dependence on thermoelectric energy for hydropower complementation. The results of the optimized design show that a PV panel tilt of approximately 3 degrees can generate energy at the lowest cost (from R $298.00/MWh to R$312.00/MWh, depending on the geographical location of the FLOATING PV platform on the reservoir). From an energy perspective, the average energy gain generated by the hydroelectric plant after adding the floating PV generation was 76%, whereas the capacity factor increased by 17.3% on average. In terms of equivalent inflow, the PV source has a seasonal profile that compliments the natural inflow of the river. Overall, the proposed coordinated operation could replace much of the thermoelectric generation in Brazil.The authors would like to thank the Brazilian National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq; in Portuguese) for granting a productivity in research scholarship to Prof. Regina Mambeli Barros (PQ2, Process number: 301986/2015-0) and Prof. Geraldo Lúcio Tiago Filho and to the Brazilian Coordination for the Improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Capes; in Portuguese) for granting the Master of Science scholarship to Naidion Motta Silvério and the Doctorate scholarship to Ivan Felipe da Silva dos Santos.Silverio, N.; Barros, R.; Tiago Filho, GL.; Redón-Santafé, M.; Silva Dos Santos, IF.; De Mello Valerio, VE. (2018). Use of floating PV plants for coordinated operation with hydropower plants: Case study of the hydroelectric plants of the Sao Francisco River basin. Energy Conversion and Management. 171:339-349. https://doi.org/10.1016/j.enconman.2018.05.095S33934917

Project and Design of a Special Agricultural Warehouse Developed in Phases in Valencia (Spain)

[EN] This article describes the developing phases to build warehouses for a Pomelo Company at Valencian County (East of Spain). The warehouses are remarkable because they did not have many intermediate columns. Spatial and lightweight solutions are adopted and described. In the Projects also natural ventilation and lighting have been considered with a successfully result. Erection conditions and Regulations have been taken also account. It has been an inspiration motive for other consultants.Ferrer Gisbert, CM.; Ferrer-Gisbert, P.; Ferran Gozalvez, JJ.; Redón-Santafé, M.; Torregrosa Soler, JB.; Sánchez-Romero, F. (2020). Project and Design of a Special Agricultural Warehouse Developed in Phases in Valencia (Spain). Current Trends in Civil & Structural Engineering. 5(5):1-8. https://doi.org/10.33552/CTCSE.2020.05.000623S185

A new photovoltaic floating cover system for water reservoirs

This paper describes a new photovoltaic floating cover system for water reservoirs developed jointly by the company CELEMIN ENERGY and the Universidad Politecnica de Valencia. The system consists of polyethylene floating modules which, with the use of tension producing elements and elastic fasteners, are able to adapt to varying reservoir water levels. A full-scale plant located near Alicante (Spain) was built in an agriculture reservoir to study the behaviour of the system. The top of the reservoir has a surface area of 4700 m(2) but only 7% of such area has been covered with the fixed solar system. The system also minimizes evaporation losses from water reservoirs. (C) 2013 Elsevier Ltd. All rights reserved.The English revision of this paper was funded by the Universidad Politecnica de Valencia, Spain.Ferrer Gisbert, CM.; Ferran Gozalvez, JJ.; Redón Santafé, M.; Ferrer-Gisbert, P.; Sánchez-Romero, F.; Torregrosa Soler, JB. (2013). A new photovoltaic floating cover system for water reservoirs. Renewable Energy. (60):63-70. doi:10.1016/j.renene.2013.04.007S63706