Assessment of climate change vulnerability of farm households in Pyapon District, a delta region in Myanmar

Sea level rise causes saltwater intrusion and flooding of agricultural land and ultimately threatens the livelihoods of farm households in the delta region of Myanmar. Empirical research on the effects of climate change on the delta's agriculture and an assessment of the vulnerability are becoming necessary. This study explores the vulnerability of farm households to sea level rise using two methods: the Livelihood Vulnerability Index (LVI), which is comprised of 37 indicators, and the Socioeconomic Vulnerability Index (SeVI), which contains 35 indicators. Interviews with 178 farmers were conducted in Bogale, Pyapon and Dedaye Townships in Pyapon District. In addition, 7 focus group discussions were performed, with at least 2 discussions in each Township. Both methods identify Bogale to be the most vulnerable Township, followed by Dedaye and Pyapon Townships. Following the LVI approach, Bogale Township has the highest sensitivity to climate effects and the highest exposure to natural hazards, but also a higher adaptive capacity than the other townships. In contrast using the SeVI approach, Bogale was found to have the highest sensitivity and exposure to natural hazards but the lowest adaptive capacity score. The study found that the climate change adaptation measures taken by the farmers are important to limit vulnerable to the adverse effects of climate change and thus promotion of the adaptive capacity of farmers is important for the delta region of Myanmar

Failure analysis of the fasten system of wheels used in mining pickup trucks

Regardless of their specific applications, all the vehicles used in mining operations are subjected to severe working conditions that reduce in a considerable amount, their active in-service life. In this work, the causes that promote failure of the fasten system and subsequent ejection of the wheels of passenger pickup trucks used in open-pit mines are analysed. By means of scanning electron microscopy, optical microscopy analyses and hardness tests, it was found that failure of the fasten system is characterised by a series of synergetic steps that include, the plastic deformation of the lug nuts caused by deficient tightening practices, fatigue and plastic deformation of the bolts. When combined, these phenomena leaded to the formation of cracks that propagated in the radial direction of these elements. The reasons that promote the development of this kind of failure are presented and discussed in this investigation. © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Análisis predictivo de las perspectivas de uso de identificadores por radiofrecuencia (rfid) en el Ecuador

RFID (Identificación por Radiofrecuencia) es un sistema inalámbrico basado en la emisión de ondas de radio frecuencia para transmitir y capturar datos. La tecnología está basada en etiquetas formadas por un microchip y un circuito impreso en forma de antena que emiten una serie de dígitos llamados EPC (código electrónico de producto). Esté código puede ser rastreado a largas distancias hasta un repositorio de información, lo que permite que a más de identificar el producto se conozca más información sobre el mismo. Los RFIDs mejoran procesos en la cadena de distribución de muchas empresas. Actualmente grandes compañías están aplicando RFID en sus procesos permitiéndoles resultados favorables. El presente artículo muestra una breve descripción de la tecnología RFID, su estado actual y sus diferentes aplicaciones en diversas empresas a nivel mundial. Finalmente, plantearemos perspectivas del uso y aplicación de RFID en el mercado ecuatoriano, basándonos en estudios realizados con una muestra de empresas del sector de distribución tecnológica y proyectos que se estén planificando en nuestro país.RFID (Radio Frequency Identification) is a wireless system based on the emission of radio frequency waves to transmit and capture data. The technology is based on labels consist of a microchip and a printed circuit board in the form of antenna that emit a series of digits called EPC (Electronic Product Code). The code can be traced over long distances up to a repository of information, which allows more than identify the product, knowing more about them. The RFIDs improve processes in the distribution chain of many businesses. Currently, large companies are implementing RFID in their processes allowing favorable results. This paper presents a brief overview of RFID technology, its current state and its various applications in a variety of companies worldwide. Finally, raise prospects of the use and application of RFID in the Ecuadorian market, based on studies conducted with a sample of companies in the distribution sector technology and projects that are being planned in our country

Nematic Films and Radially Anisotropic Delaunay Surfaces

We develop a theory of axisymmetric surfaces minimizing a combination of surface tension and nematic elastic energies which may be suitable for describing simple film and bubble shapes. As a function of the elastic constant and the applied tension on the bubbles, we find the analogues of the unduloid, sphere, and nodoid in addition to other new surfaces.Comment: 15 pages, 18 figure

The arrow- debreu's model is a static model

This article, which tomis part of a wider study, presents the Arrow-Debreu's model, analyzing some of its theoretical limitations. Its main objective is to show that the model is static and that dynamic considerations can not be inferred from it. Besides, it shows that most misinterpretations of the model arise from considering it a dynamic modeloEn este artículo, parte de un estudio más amplio, de hace una presentación del modelo Arrow-Debreu y se analizan algunas de sus limitaciones teóricas. Su objetivo principal es mostrar que el modelo es estático y que no pueden derivarse consideraciones dinámicas de él. Además, se muestra que las principales malas interpretaciones del modelo surgen al considerársele un modelo dinámico

El modelo arrow-debreu es un modelo estático

En este artículo, parte de un estudio más amplio, de hace una presentación del modelo Arrow-Debreu y se analizan algunas de sus limitaciones teóricas. Su objetivo principal es mostrar que el modelo es estático y que no pueden derivarse consideraciones dinámicas de él. Además, se muestra que las principales malas interpretaciones del modelo surgen al considerársele un modelo dinámico.This article, which tomis part of a wider study, presents the Arrow-Debreu's model, analyzing some of its theoretical limitations. Its main objective is to show that the model is static and that dynamic considerations can not be inferred from it. Besides, it shows that most misinterpretations of the model arise from considering it a dynamic model

El modelo de generaciones traslapadas como modelo monetario

En este artículo se presenta el modelo básico de generaciones translapadas de intercambio puroy se introduce el modelo OLG monetario. Se examinan la condiciones que garantizan la existencia de equilibrios bajo expectativas racionales y sus características de optimalidad, y se describen las tendencias actuales en la literatura reciente sobre los desarrollos del modelo OLG cómo modelo monetario.This article introduces the basic overlapping generations model (OLG) of pure exchange and the OLG model with fiat money. It examines conditions under what rational expectations equilibria do exist, and studies the properties of optimality of those equilibria. Furthermore, it describes the recent tendencies in the economic literature about the developments of the OLG model as a monetary modelo

Evaluating the RCCI operating range limits in a high compression ratio medium-duty diesel engine fueled with biodiesel and ethanol

[EN] This work investigates the load limits of reactivity controlled compression ignition combustion, a dual-fuel concept which combines port fuel injection of low-reactivity fuels with direct injection of diesel fuel, in a medium-duty diesel engine. The experiments were conducted in a single-cylinder diesel engine derived from the multi-cylinder production engine. In this sense, the stock turbocharger and exhaust gas recirculation systems were replaced by an external compressor and dedicated low-pressure exhaust gas recirculation loop, respectively. Additionally, a port fuel injector was installed in the intake manifold to allow gasoline injection. First, this article presents some results highlighting the effect of the exhaust gas recirculation rate, gasoline fraction, diesel start of injection, diesel injection strategy and intake temperature on the emissions, performance and combustion development in a representative operating condition: 1200r/min and 6.5bar indicated mean effective pressure (25% load). Later, with the aim of showing the reactivity controlled compression ignition potential, the best results in terms of performance and emissions at 25% load are compared against the multi-cylinder diesel engine from 950 to 2200r/min. Reactivity controlled compression ignition engine tests were developed taking into account limitations in nitrogen oxides (NOx) and soot emissions, in-cylinder pressure and maximum pressure rise rate. Finally, keeping the same constraints for testing, the load limits of reactivity controlled compression ignition concept are evaluated for all the engine speeds. Results suggest that reactivity controlled compression ignition allows fulfilling EURO VI limits for NOx and soot emissions without using selective catalytic reduction and diesel particulate filter aftertreatment systems at 25% load at all the engines speeds, providing better indicated efficiency than conventional diesel operation in most operating points. In addition, the maximum engine load that ensured the aforementioned constraints was around 35% for all the engine speeds, with a maximum indicated mean effective pressure of 8.8bar at 2200r/min. In this case, a strong reduction in carbon monoxide (CO) and unburned hydrocarbon (HC) emissions compared to the cases of 25% load was achieved at all the engine speeds.Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Balloul, I.; Pradel, G. (2017). Evaluating the RCCI operating range limits in a high compression ratio medium-duty diesel engine fueled with biodiesel and ethanol. International Journal of Engine Research. 18(1-2):66-80. https://doi.org/10.1177/1468087416678500S6680181-2Yao, M., Zheng, Z., & Liu, H. (2009). Progress and recent trends in homogeneous charge compression ignition (HCCI) engines. Progress in Energy and Combustion Science, 35(5), 398-437. doi:10.1016/j.pecs.2009.05.001Maurya, R. K., & Agarwal, A. K. (2011). Experimental study of combustion and emission characteristics of ethanol fuelled port injected homogeneous charge compression ignition (HCCI) combustion engine. Applied Energy, 88(4), 1169-1180. doi:10.1016/j.apenergy.2010.09.015Cerit, M., & Soyhan, H. S. (2013). Thermal analysis of a combustion chamber surrounded by deposits in an HCCI engine. Applied Thermal Engineering, 50(1), 81-88. doi:10.1016/j.applthermaleng.2012.06.004Singh, A. P., & Agarwal, A. K. (2012). Combustion characteristics of diesel HCCI engine: An experimental investigation using external mixture formation technique. Applied Energy, 99, 116-125. doi:10.1016/j.apenergy.2012.03.060Maurya, R. K., & Agarwal, A. K. (2011). Experimental investigation on the effect of intake air temperature and air–fuel ratio on cycle-to-cycle variations of HCCI combustion and performance parameters. Applied Energy, 88(4), 1153-1163. doi:10.1016/j.apenergy.2010.09.027Liu, H., Yao, M., Zhang, B., & Zheng, Z. (2008). Effects of Inlet Pressure and Octane Numbers on Combustion and Emissions of a Homogeneous Charge Compression Ignition (HCCI) Engine. Energy & Fuels, 22(4), 2207-2215. doi:10.1021/ef800197bBenajes, J., García, A., Domenech, V., & Durrett, R. (2013). An investigation of partially premixed compression ignition combustion using gasoline and spark assistance. Applied Thermal Engineering, 52(2), 468-477. doi:10.1016/j.applthermaleng.2012.12.025Benajes, J., Tormos, B., Garcia, A., & Monsalve-Serrano, J. (2014). Impact of Spark Assistance and Multiple Injections on Gasoline PPC Light Load. SAE International Journal of Engines, 7(4), 1875-1887. doi:10.4271/2014-01-2669Pastor, J. V., García-Oliver, J. M., García, A., Micó, C., & Durrett, R. (2013). A spectroscopy study of gasoline partially premixed compression ignition spark assisted combustion. Applied Energy, 104, 568-575. doi:10.1016/j.apenergy.2012.11.030Benajes, J., Molina, S., García, A., Monsalve-Serrano, J., & Durrett, R. (2014). Conceptual model description of the double injection strategy applied to the gasoline partially premixed compression ignition combustion concept with spark assistance. Applied Energy, 129, 1-9. doi:10.1016/j.apenergy.2014.04.093Benajes, J., Molina, S., García, A., Monsalve-Serrano, J., & Durrett, R. (2014). Performance and engine-out emissions evaluation of the double injection strategy applied to the gasoline partially premixed compression ignition spark assisted combustion concept. Applied Energy, 134, 90-101. doi:10.1016/j.apenergy.2014.08.008Kokjohn, S. L., Hanson, R. M., Splitter, D. A., & Reitz, R. D. (2009). Experiments and Modeling of Dual-Fuel HCCI and PCCI Combustion Using In-Cylinder Fuel Blending. SAE International Journal of Engines, 2(2), 24-39. doi:10.4271/2009-01-2647Klos, D., Janecek, D., & Kokjohn, S. (2015). Investigation of the Combustion Instability-NOx Tradeoff in a Dual Fuel Reactivity Controlled Compression Ignition (RCCI) Engine. SAE International Journal of Engines, 8(2), 821-830. doi:10.4271/2015-01-0841Kokjohn, S. L., Musculus, M. P. B., & Reitz, R. D. (2015). Evaluating temperature and fuel stratification for heat-release rate control in a reactivity-controlled compression-ignition engine using optical diagnostics and chemical kinetics modeling. Combustion and Flame, 162(6), 2729-2742. doi:10.1016/j.combustflame.2015.04.009Kokjohn, S., Reitz, R. D., Splitter, D., & Musculus, M. (2012). Investigation of Fuel Reactivity Stratification for Controlling PCI Heat-Release Rates Using High-Speed Chemiluminescence Imaging and Fuel Tracer Fluorescence. SAE International Journal of Engines, 5(2), 248-269. doi:10.4271/2012-01-0375Kokjohn, S. L., Hanson, R. M., Splitter, D. A., & Reitz, R. D. (2011). Fuel reactivity controlled compression ignition (RCCI): a pathway to controlled high-efficiency clean combustion. International Journal of Engine Research, 12(3), 209-226. doi:10.1177/1468087411401548Desantes, J. M., Benajes, J., García, A., & Monsalve-Serrano, J. (2014). The role of the in-cylinder gas temperature and oxygen concentration over low load reactivity controlled compression ignition combustion efficiency. Energy, 78, 854-868. doi:10.1016/j.energy.2014.10.080Dempsey, A. B., Walker, N. R., & Reitz, R. D. (2013). Effect of Piston Bowl Geometry on Dual Fuel Reactivity Controlled Compression Ignition (RCCI) in a Light-Duty Engine Operated with Gasoline/Diesel and Methanol/Diesel. SAE International Journal of Engines, 6(1), 78-100. doi:10.4271/2013-01-0264Benajes, J., García, A., Pastor, J. M., & Monsalve-Serrano, J. (2016). Effects of piston bowl geometry on Reactivity Controlled Compression Ignition heat transfer and combustion losses at different engine loads. Energy, 98, 64-77. doi:10.1016/j.energy.2016.01.014Benajes, J., Pastor, J. V., García, A., & Monsalve-Serrano, J. (2015). An experimental investigation on the influence of piston bowl geometry on RCCI performance and emissions in a heavy-duty engine. Energy Conversion and Management, 103, 1019-1030. doi:10.1016/j.enconman.2015.07.047Pearson, R. J., & Turner, J. W. G. (2014). The role of alternative and renewable liquid fuels in environmentally sustainable transport. Alternative Fuels and Advanced Vehicle Technologies for Improved Environmental Performance, 19-51. doi:10.1533/9780857097422.1.19Benajes, J., Molina, S., García, A., & Monsalve-Serrano, J. (2015). Effects of low reactivity fuel characteristics and blending ratio on low load RCCI (reactivity controlled compression ignition) performance and emissions in a heavy-duty diesel engine. Energy, 90, 1261-1271. doi:10.1016/j.energy.2015.06.088Benajes, J., Molina, S., García, A., & Monsalve-Serrano, J. (2015). Effects of direct injection timing and blending ratio on RCCI combustion with different low reactivity fuels. Energy Conversion and Management, 99, 193-209. doi:10.1016/j.enconman.2015.04.046Benajes, J., Pastor, J. V., García, A., & Monsalve-Serrano, J. (2015). The potential of RCCI concept to meet EURO VI NOx limitation and ultra-low soot emissions in a heavy-duty engine over the whole engine map. Fuel, 159, 952-961. doi:10.1016/j.fuel.2015.07.064Payri, R., Climent, H., Salvador, F. J., & Favennec, A. G. (2004). Diesel Injection System Modelling. Methodology and Application for a First-generation Common Rail System. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 218(1), 81-91. doi:10.1243/095440704322829191Payri, R., Salvador, F. J., Martí-Aldaraví, P., & Martínez-López, J. (2012). Using one-dimensional modeling to analyse the influence of the use of biodiesels on the dynamic behavior of solenoid-operated injectors in common rail systems: Detailed injection system model. Energy Conversion and Management, 54(1), 90-99. doi:10.1016/j.enconman.2011.10.004Payri, R., García, A., Domenech, V., Durrett, R., & Plazas, A. H. (2012). An experimental study of gasoline effects on injection rate, momentum flux and spray characteristics using a common rail diesel injection system. Fuel, 97, 390-399. doi:10.1016/j.fuel.2011.11.065Desantes, J. M., Payri, R., Pastor, J. M., & Gimeno, J. (2005). EXPERIMENTAL CHARACTERIZATION OF INTERNAL NOZZLE FLOW AND DIESEL SPRAY BEHAVIOR. PART I: NONEVAPORATIVE CONDITIONS. Atomization and Sprays, 15(5), 489-516. doi:10.1615/atomizspr.v15.i5.20Desantes, J. M., Pastor, J. V., Payri, R., & Pastor, J. M. (2005). EXPERIMENTAL CHARACTERIZATION OF INTERNAL NOZZLE FLOW AND DIESEL SPRAY BEHAVIOR. PART II: EVAPORATIVE CONDITIONS. Atomization and Sprays, 15(5), 517-544. doi:10.1615/atomizspr.v15.i5.30Payri, F., Olmeda, P., Martín, J., & García, A. (2011). A complete 0D thermodynamic predictive model for direct injection diesel engines. Applied Energy, 88(12), 4632-4641. doi:10.1016/j.apenergy.2011.06.005Payri, F., Olmeda, P., Martin, J., & Carreño, R. (2014). A New Tool to Perform Global Energy Balances in DI Diesel Engines. SAE International Journal of Engines, 7(1), 43-59. doi:10.4271/2014-01-0665Ma, S., Zheng, Z., Liu, H., Zhang, Q., & Yao, M. (2013). Experimental investigation of the effects of diesel injection strategy on gasoline/diesel dual-fuel combustion. Applied Energy, 109, 202-212. doi:10.1016/j.apenergy.2013.04.01