The Role of Relative Price Volatility in the Efficiency of Investment Allocation

This paper estimates the impact of relative price volatility on sector-level investment allocation using a panel of 65 countries with data for 26 manufacturing industries over the period 1985-2003. Results indicate that volatility distorts efficient investment allocation in that investment is not necessarily devoted to relatively more productive sectors, especially in emerging market economies that are highly exposed and may lack the necessary institutions to deal with it successfully. This is evidence in support of theories suggesting that relative price volatility provides incentives for entrepreneurs to adopt more “malleable” but less productive production technologies, enabling them to accommodate more easily abrupt and frequent changes in relative prices, but at the cost of using less productive technologies.Sector-level TFP, Relative price volatility, Investment allocation, Financial crises, Emerging markets, Malleable technologies

Extended Hamiltonian systems in multisymplectic field theories

We consider Hamiltonian systems in first-order multisymplectic field theories. We review the properties of Hamiltonian systems in the so-called restricted multimomentum bundle, including the variational principle which leads to the Hamiltonian field equations. In an analogous way to how these systems are defined in the so-called extended (symplectic) formulation of non-autonomous mechanics, we introduce Hamiltonian systems in the extended multimomentum bundle. The geometric properties of these systems are studied, the Hamiltonian equations are analyzed using integrable multivector fields, the corresponding variational principle is also stated, and the relation between the extended and the restricted Hamiltonian systems is established. All these properties are also adapted to certain kinds of submanifolds of the multimomentum bundles in order to cover the case of almost-regular field theories.Comment: 36 pp. The introduction and the abstract have been rewritten. New references are added and some little mistakes are corrected. The title has been slightly modifie

Building micro-soccer-balls with evaporating colloidal fakir drops

Evaporation-driven particle self-assembly can be used to generate three-dimensional microstructures. We present a new method to create these colloidal microstructures, in which we can control the amount of particles and their packing fraction. To this end, we evaporate colloidal dispersion droplets on a special type of superhydrophobic micro-structured surface, on which the droplet re- mains in Cassie-Baxter state during the entire evaporative process. The remainders of the droplet consist of a massive spherical cluster of the microspheres, with diameters ranging from a few tens up to several hundreds of microns. We present scaling arguments to show how the final particle packing fraction of these balls depends on the dynamics of the droplet evaporation.Comment: Manuscript Submitted to Physical Review Letters, 29th February 201

Updating all shortest paths in dynamic graphs with edge insertions.

El presente trabajo de investigación propone el diseño e implementación de un nuevo algoritmo para actualización de APSP en grafos dinámicos con inserción de arcos en grandes volúmenes de datos, con base a ideas preliminares desarrolladas en el grupo LAMIC de la Universidad Distrital. Los algoritmos clásicos tales como Dijsktra o Floyd-Warshall, requieren mucho tiempo en calcular el APSP cada vez que un grafo dinámico se actualiza. El algoritmo propuesto, actualiza las distancias con base en cálculos obtenidos con previas configuraciones de la estructura del grafo. Así mismo se propone una nueva variante del algoritmo que no solo compute la distancia, sino el camino como tal (secuencia de nodos que une cada nodo con los demás).Many activities of modern day living operate on the basis of graph structures that change over time (e.g. social networks, city traffic navigation, disease transmission paths). Hence, the problem of dynamically maintaining properties of such structures after modifying one of its edges (or links), specially for large-scale graphs, has received a great amount of attention in recent years. We address the particular case of updating all-pairs shortest distances upon \emph{incremental} changes, i.e. re-computing shortest distances among all the nodes of a graph when a new or smaller shortcut between two nodes arises. We build upon the naive algorithm that visits all pairs of nodes comparing if the new shortcut shortens the distances, and propose a simple variation that instead chooses pairs of source and target nodes, only from the \emph{affected} shortest paths. The new algorithm works with an optimal data structure, constant query time and worst-case $O(n^2)$ update cost, although our results on synthetic datasets hints at its practicality when compared with state-of-the-art approaches

Calidad de sentencias de primera y segunda instancia sobre el delito de robo agravado, en el expediente N° 01825-2016-0-1801-JR-PE-09, del distrito judicial de Lima – Lima, 2021.

La investigación tuvo como problema: ¿Cuál es la calidad de las sentencias de primera y segunda instancia, sobre el delito de robo agravado, según los parámetros normativos, doctrinarios y jurisprudenciales pertinentes, EN EL EXPEDIENTE N° 01825- 2016-0-1801-JR-PE-09, “DEL DISTRITO JUDICIAL DE LIMA – LIMA, 2021?; el objetivo fue: determinar la calidad de las sentencias en estudio. Es de tipo, cuantitativo cualitativo, nivel exploratorio descriptivo, y diseño no experimental, retrospectivo y transversal. La unidad de análisis fue un expediente judicial, seleccionado mediante muestreo por conveniencia; para recolectar los datos se utilizaron las técnicas de la observación y el análisis de contenido; y como instrumento una lista de cotejo, validado mediante juicio de expertos. Los resultados revelaron que la calidad de la parte expositiva, considerativa y resolutiva, pertenecientes a: la sentencia de primera instancia fue de rango: muy alta, muy alta y muy alta; y de la sentencia de segunda instancia: muy alta, muy alta y muy alta. Se concluyó, que la calidad de las sentencias de primera y de segunda instancia, fueron de rango muy alta y muy alta, respectivamenteTesi

Solution Properties Of Polyol Ester Lubricants Designed For Use With R-32 And Related Low GWP Refrigerant Blends

Since the Montreal and Kyoto protocols mandated the phase-out of refrigerants which deplete the ozone layer and have high global warming potential, respectively, there has been an extensive global initiative to identify suitable environmentally sustainable alternatives. Replacement of CFCs and HCFCs with HFCs has successfully addressed the objectives of the Montreal protocol. However, most HFCs used today are not acceptable for the long term because they have GWPs greater than 1,000. Low GWP refrigerants that are, or will be, considered as replacements for HFCs include R32, hydrocarbons such as R290, carbon dioxide (R744), and hydroflouro olefins such as HFO1234yf and HFO1234ze(E).It has already been determined that in many cases new lubricants will be required for these refrigerants to ensure long term compressor reliability and the best possible system performance. The primary issue that must be addressed is the unacceptable high mutual solubility of the refrigerant and lubricant at high lubricant concentrations. The first consequence of this high solubility is the excessive reduction of viscosity that affects proper lubrication of the compressor and components, sealing of clearances between low and high pressure sides of the compressor. The second is a significant change in the steady state amount of oil in the circulation stream in the system, which can impact the heat transfer performance in both the evaporator and condenser.Another potential minor issue is refrigerant flash evaporation at discharge creating excessive foaming and noise. This paper describes details of a method used to measure the thermophysical properties of refrigerant lubricant mixtures. The general methods for data acquisition and processing, along with creation of Daniel charts were in accord with those developed by Chris Seeton. The results of measurements involving mixtures of traditional POEs with R-32 or R-410A shows that lubricant viscosities in the compressor at various conditions within the normal operating envelope decrease by as much as 25-54%. This illustrates the excessive lubricant viscosity dilution of R-32 relative to R-410A with traditional POs used today with HFCs refrigerants. The solution property measurement technique was also used to develop a class of advanced ester POE lubricants optimized for R-32 to eliminates the viscosity dilution problem. Significant energy savings can be achieved through proper optimization of lubricant/refrigerant solution properties to provide the best balance of lubrication in the compressor while maintaining excellent heat transfer in the refrigeration cycle

Solution Properties Of Polyol Ester Lubricants Designed For Use With R-32 And Related Low GWP Refrigerant Blends

Since the Montreal and Kyoto protocols mandated the phase-out of refrigerants which deplete the ozone layer and have high global warming potential, respectively, there has been an extensive global initiative to identify suitable environmentally sustainable alternatives. Replacement of CFCs and HCFCs with HFCs has successfully addressed the objectives of the Montreal protocol. However, most HFCs used today are not acceptable for the long term because they have GWPs greater than 1,000. Low GWP refrigerants that are, or will be, considered as replacements for HFCs include R32, hydrocarbons such as R290, carbon dioxide (R744), and hydroflouro olefins such as HFO1234yf and HFO1234ze(E).It has already been determined that in many cases new lubricants will be required for these refrigerants to ensure long term compressor reliability and the best possible system performance. The primary issue that must be addressed is the unacceptable high mutual solubility of the refrigerant and lubricant at high lubricant concentrations. The first consequence of this high solubility is the excessive reduction of viscosity that affects proper lubrication of the compressor and components, sealing of clearances between low and high pressure sides of the compressor. The second is a significant change in the steady state amount of oil in the circulation stream in the system, which can impact the heat transfer performance in both the evaporator and condenser.Another potential minor issue is refrigerant flash evaporation at discharge creating excessive foaming and noise. This paper describes details of a method used to measure the thermophysical properties of refrigerant lubricant mixtures. The general methods for data acquisition and processing, along with creation of Daniel charts were in accord with those developed by Chris Seeton. The results of measurements involving mixtures of traditional POEs with R-32 or R-410A shows that lubricant viscosities in the compressor at various conditions within the normal operating envelope decrease by as much as 25-54%. This illustrates the excessive lubricant viscosity dilution of R-32 relative to R-410A with traditional POs used today with HFCs refrigerants. The solution property measurement technique was also used to develop a class of advanced ester POE lubricants optimized for R-32 to eliminates the viscosity dilution problem. Significant energy savings can be achieved through proper optimization of lubricant/refrigerant solution properties to provide the best balance of lubrication in the compressor while maintaining excellent heat transfer in the refrigeration cycle

Comparative Study of Energy Savings for Various Control Strategies in the Tunnel Lighting System

Tunnel lighting is the most significant component in total energy consumption in the whole infrastructure. Hence, various lighting control strategies based on light-emitting diode (LED) technology have been investigated to conserve energy by decreasing luminaires’ operating time. In this study, four kinds of tunnel lighting control strategies and the development of their associated technologies are evaluated: no-control low-consumption lamps (LCL), time-scheduling control strategy (TSCS), daylight adaptation control strategy (DACS), and intelligent control strategy (ICS). This work investigates the relationship between initial investment and electrical costs as a function of tunnel length (L) and daily traffic volume (N) for the four control strategies. The analysis was performed using 100-day data collected in eleven Chinese tunnels. The tunnel length (L) ranged from 600 m to 3300 m and the daily traffic volume (N) ranged from 700 to 2500. The results showed that initial investment costs increase with L for all control strategies. Also, the electricity costs for the LCL, TSCS, and DACS strategies increased linearly with L, whereas the electricity cost for the ICS strategy has an exponential growth with L and N. The results showed that for a lifetime equal to or shorter than 218 days, the LCL strategy offered the best economical solution; whereas for a lifetime longer than 955 days, the ICS strategy offered the best economical solution. For a lifetime between 218 and 955 days, the most suitable strategy varies with tunnel length and traffic volume. This study’s results can guide the decision-making process during the tunnel lighting system’s design stage.Zhejiang Provincial Natural Science Foundation of China - LQ21E080005National Natural Science Foundation of China - 61701069 and 61971248Major Science and Technology Special Project in Jiangbei District, Ningbo City - 201901A0

Reglas de combinación de los efectos de las tres componentes de terremotos y respuesta crítica

La precisión de las reglas de combinación del 30% y SRSS, y la orientación crítica de las componentes de terremotos se estudian en este trabajo. Se analizan modelos estructurales complejos que representan edificios de baja y mediana altura. Se realiza un análisis estadístico de la precisión de las reglas de combinación aplicadas a parámetros de respuesta individuales y múltiples. El efecto de la correlación entre las componentes de los terremotos en dicha precisión también se estudia. Finalmente, se realizan análisis con varios ángulos de incidencia de las componentes con la finalidad de encontrar la orientación crítica. Los resultados muestran que las reglas subestiman la carga axial en columnas, pero sobreestiman razonablemente los cortantes de entrepiso. Ambas reglas son más conservadoras cuando los modelos se excitan por las tres componentes. Los efectos individuales pueden estar altamente correlacionados, incluso para componentes principales no correlacionadas. Las reglas no siempre son precisas para valores pequeños de coeficientes de correlación, y valores altos de éstos no siempre están relacionados a una estimación imprecisa de la respuesta combinada. La precisión de las reglas de combinación depende del grado de correlación de las componentes, del parámetro de respuesta, de la localización del elemento considerado y del nivel de deformación estructural

Globalización y transformación política y económica de México.

This article aims to analyze the key elements of Mexico's economic transformation in the current process of globalization. For this, it has been structured in three sections. First a brief summary is made about the process of Import Substitution Industrialization in Mexico. Second, it will be analyzed the transition period of economic policy (1982-1993) that would play a significant role in Mexico's structural change. Finally, with the information obtained, some conclusions will be presented.El presente artículo pretende analizar los elementos clave de la transformación económica de México en el actual proceso de globalización. Para ello se ha estructurado de la siguiente manera en tres secciones. Primero se hace un recorrido breve sobre el proceso de Industrialización por Sustitución de Importaciones en México. Segundo, se analiza el periodo de transición de política económica (1982-1993) que tendría un papel significativo en el cambio estructural de México. Por último, con la información obtenida se plantearan algunas conclusiones