Compilation of Published Estimates of Annual Geocenter Motions Using Space Geodesy

The definition of the term "geocenter motion" depends on the adopted origin of the reference frame. Common reference frames used in Space Geodesy include: the center of mass of the whole Earth (CM), the center of mass of the Solid Earth without mass load (CE), and the center of figure of the outer surface of the Solid Earth (CF). There are two established definitions of the term geocenter: one, the vector offset of CF relative to CM and, two, the reverse, the vector offset of CM relative to CF. Obviously, their amplitude is the same and their phase differs by 180 deg. Following Dong et al. [2003], we label the first X(sub CF, sup CM) and the second X(sup CF, sup CM) (i.e., the superscript represents the frame, the subscript represents any point in the frame)

Structural Economic Model for Ecuador: a Dollar-ized and Oil-ized

El trabajo desarrolla un Modelo Estructural con las principales características macroeconómicas de la economía ecuatoriana. Modela los principales canales de transmisión de una economía pequeña, abierta y dolarizada, altamente dependiente de la producción de petróleo y las remesas del exterior. Se estima por métodos bayesianos para el período 2001-2010. El modelo permite analizar los principales riesgos que afectan el desempeño macroeconómico, incluyendo los shocks externos. También se subraya el efecto de la política fiscal así como el papel independiente y significativo del valor agregado petrolero en la economía doméstica.The paper develops a Structural Model with the main macroeconomic features of the Ecuadorian economy. It models the main transmission channels of a small open and dollarized economy, highly dependent on oil production and foreign remittances. It is estimated by Bayesian methodsfor the period 2001- 2010. The framework highlights the main risks affecting the macroeconomic performance, including the importance of international shocks. It also underscores the importance of the fiscal policies and the independent and significant role of the oil value added in the domestic economy.Facultad de Ciencias Económica

Risky Banking: Optimal Loan Quantity and Portfolio Quality Choices

In this paper we construct a model of a "risky bank". The bank faces excess demand in the loan market, can sort loan applicants by an observable measure of quality, and faces a small but positive probability of default on its loan portfolio. The bank uses two policies to allocate credit: - Tighten restrictions on loan quality - Limit the number of loans of a given quality We show that the level of default risk and other structural conditions have important e®ects on the market for loanable funds and the bank's optimal policies (loan rates, deposit rates, and lending standards). The structural conditions that we examine are monitoring costs, returns on alternative investments, firms' minimum funding requirements, and the level of the reserve requirement. The model provides insight into several stylized facts observed in loan markets, especially in developing countries.Facultad de Ciencias Económica

Risky Banking: Optimal Loan Quantity and Portfolio Quality Choices

In this paper we construct a model of a "risky bank". The bank faces excess demand in the loan market, can sort loan applicants by an observable measure of quality, and faces a small but positive probability of default on its loan portfolio. The bank uses two policies to allocate credit: - Tighten restrictions on loan quality - Limit the number of loans of a given quality We show that the level of default risk and other structural conditions have important e®ects on the market for loanable funds and the bank's optimal policies (loan rates, deposit rates, and lending standards). The structural conditions that we examine are monitoring costs, returns on alternative investments, firms' minimum funding requirements, and the level of the reserve requirement. The model provides insight into several stylized facts observed in loan markets, especially in developing countries.Facultad de Ciencias Económica

Nutrient uptake in a stream affected by hydropower plants: comparison between stream channels and diversion canals

12 páginas, 3 figuras, 4 tablas.Small hydropower plants divert part of the water from wide and physically complex stream channels with active hyporheic areas to narrow and hydraulically simple concrete canals, and thus, might affect nutrient dynamics. We compared nutrient uptake in diversion canals and in stream channels in the Leitzaran Stream (Basque Country, northern Spain). We predicted that simple morphology in diversion canals will result in lower nutrient uptake in canals than in stream channels. Periphytic chlorophyll and biomass did not differ significantly between reach types. Water was significantly deeper and faster in canals than in stream channels, but the transient storage zone did not differ significantly between reach types. There were no significant differences between uptake length for neither phosphate nor ammonium between reach types. Uptake length in both stream channels and diversion canals decreased with discharge, in a pattern similar to that previously described for pristine rivers across the world. Uptake velocity and uptake rate for phosphate did not differ signifi- cantly between reach types, but in the case of ammonium both retention metrics were significantly larger in the diversion canals. Results suggest that although hydropower schemes have minor effects on nutrient retention, these depend on the proportion of flow diverted.This research has been funded by the Spanish Department of Science and Technology, the University of the Basque Country, and the European Regional Development Fund, through projects 9/UPV00118.310-14476/ 2002 and BOS2003-04466.Peer reviewe

A Novel Approach to CubeSat Flight Software Development Using Robot Operating System (ROS)

The large-scale development and deployment of small satellite systems in the modern aerospace sector motivates the parallel development of new flight software and avionics systems to meet the demands of modern spaceflight operations. Robot Operating System (ROS) provides an open-sourced and modular software framework that can be adapted for space-faring purposes in addition to the standard robotics operations that it is intended for. At the University of Florida’s Advanced Autonomous Multiple Spacecraft (ADAMUS) Laboratory, this framework, serving as the first flight-ready implementation of ROS in spacecraft flight software architecture, will be used in two upcoming CubeSat missions: (1) The Drag De-Orbit Device (D3) mission and (2) the PAssive Thermal Coating Observatory Operating in Low earth orbit (PATCOOL) mission. These missions will serve to validate the reusability of this software and the core functionality contained within, supporting tasks such as data link transmission, command processing, GNC (guidance, navigation & control), avionics system health diagnostics and soft/hard reboot instantiation. These capabilities draw upon the foundations of ROS in which tasks are handled by software modules that communicate through a language-agnostic messaging system resulting in an efficient multiprocessing architecture. Improvements and design considerations are also proposed in addition to suggestions for possible future use-cases of ROS in spaceflight software design

Ozeano Artikoko bankisaren beherakada: behaketak berrikusten, kausa fisikoak ulertzen eta etorkizuneko aldaketak iragartzen

Ozeano Artikoa bankisa mehe batez estalita dago. Bankisa klima polarra taxutzen duen faktore garrantzitsuetako bat da, eta eragina izan dezake klima-sistema globalean ere. Garrantzi hori dela eta, beharrezkoa da Artikoko bankisa horren egoerari begiratzea eta hura ulertzea eta aurreikustea. Behaketek argi eta garbi erakutsi dute izotzaren hedadura eta lodiera murrizten ari direla eta izotz iraunkorra zena aldikako izotz ari dela bilakatzen. Inolako zalantza-izpirik gabe, Artikoko bankisa gainbehera nabarian dago. Bankisaren gainbehera hori ulertzeko, aldaketa horien kausa izan litezkeen prozesu termodinamiko eta dinamiko giltzarriak aztertu behar dira. Prozesuon artean daude, besteak beste, faktore fisikoak (adibidez, epeltzeko joerak), atmosferako eta ozeanoko zirkulazioan gertatutako aldaketak, ozeanoaren gainazalera iristen den eguzki-erradiazio handiagoa eta horri lotutako izotz-albedoaren berrelikadura. Gaur egungo ereduek aurreikusten dute mende hau amaitu baino lehen Ozeano Artikoa izotzik gabe geratuko dela udako urtze-garaiaren bukaeran. Behaketek, baina, erakusten dute bankisaren beherakada ez dela ereduek iragarritako abiaduran gertatzen ari, azkarrago baizik, eta agerian uzten dute ereduak hobetzeko premia. Artikoko bankisaren gainbeherak ondorio garrantzitsuak ditu Artikoko eta Lurreko klima-sistemetan, eta, gainera, gero eta erronka handiagoak ezartzen ditu alor sozioekonomikoan, politikoan eta ekologikoan

Una metodología para la mejora del proceso de roscado con macho en fundiciones de alta resistencia

184 p.En el método planteado se tienen en cuenta los machos de corte mejores para roscar fundiciones de alta resistencia Austempered Ductile Iron(ADI) en condiciones industriales, en geometría, tipo de recubrimiento PVD y preparaciones superficiales del filo de corte. Se analizan los factores de la máquina fresadora que intervienen al roscar como son el montaje de la herramienta, la sincronización del movimiento del cabezal y la cinemática.También se tienen en cuenta las propiedades y caracterización de las fundiciones ADI, para comprender su maquinabilidad.Se aborda el conjunto de factores que intervienen, la herramienta, el proceso y el material a roscar

El principio de proporcionalidad, la incitación al odio y la libertad de expresión en la reciente Jurisprudencia del Tribunal Europeo de Derechos Humanoslos Casos Stomakhin c. Rusia, Williamson c. Alemania y Pastörs c. Alemania

El objetivo del presente artículo es presentar la reciente evolución del Tribunal Europeo de Derechos Humanos en la aplicación del principio de proporcionalidad en cuestiones referidas a la libertad de expresión y su límite en la prohibición de la incitación al odio, en los casos Stomakhin c. Rusia, Williamson c. Alemania, Pastörs c. Alemania. Se analiza el modo concreto en el que los jueces del TEDH realizan su propia ponderación aplicando el test de proporcionalidad, mostrando que incluso cuando el TEDH respeta el principio de subsidiariedad y el margen de apreciación de los Estados contratantes del Convenio, realiza su propia valoración sobre el razonamiento que los tribunales nacionales han llevado a cabo. Se resalta la particular toma de posición del TEDH ante los hechos presentados por las partes, especialmente cuando se refieren a fenómenos históricos. The objective of this article is to present the recent evolution of the European Court of Human Rights in the application of the principle of proportionality in matters related to freedom of expression and its limit in the prohibition of hate speech, in the cases Stomakhin v. Russia, Williamson v. Germany and Pastors v. Germany. The concrete way in which the judges of the ECHR make their own weighing applying the proportionality test is analysed, showing that even when the ECHR respects the principle of subsidiarity and the margin of appreciation of the Contracting States of the Convention, it makes its own assessment about the reasoning that the national courts have carried out. The particular position that the ECHR has to take facing the facts presented by the parties is highlighted too, especially when they refer to historical phenomena

Network structure and fragmentation of the Argentinean interbank markets

This paper studies the network structure and fragmentation of the Argentinean interbank market. The unsecured (CALL) and secured (REPO) markets are examined, applying complex network analysis. Results indicate that although the secured market has fewer participants, its nodes are more densely connected than the ones in the unsecured market. The interrelationships in the unsecured market are less stable, making its structure more volatile and vulnerable to negative shocks. The analysis identifies two hidden underlying subnetworks within the REPO market: one based on the transactions collateralized by Treasury bonds (REPO-T) and the other based on the operations collateralized by Central Bank (CB) securities (REPO-CB). The changes in monetary policy stance and monetary conditions seem to have a substantially smaller effect in the former submarket than in the latter one. The connectivity levels within the REPO-T market and its structure remain relatively unaffected by the (occasionally pronounced) swings in the other market segment. Hence, the REPO market shows signs of fragmentation in its inner structure, according to the type of collateral asset involved in the transactions, so the average REPO interest rate reflects the interplay between these two partially fragmented submarkets. The REPO market´s mixed structure entails one of the main sources of differentiation with respect to the CALL market.Fil: Elosegui, Pedro Luis. Banco Central de la República Argentina; ArgentinaFil: Forte, Federico. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Departamento de Economía; Argentina. Banco BBVA Argentina; ArgentinaFil: Montes Rojas, Gabriel Victorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Interdisciplinario de Economía Política de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Económicas. Instituto Interdisciplinario de Economía Política de Buenos Aires; Argentin