Constructing an overall dynamical model for a system with changing design parameter properties

This study considers the identification problem for a class of non-linear parameter-varying systems associated with the following scenario: the system behaviour depends on some specifically prescribed parameter properties, which are adjustable. To understand the effect of the varying parameters, several different experiments, corresponding to different parameter properties, are carried out and different data sets are collected. The objective is to find, from the available data sets, a common parameter-dependent model structure that best fits the adjustable parameter properties for the underlying system. An efficient Common Model Structure Selection (CMSS) algorithm, called the Extended Forward Orthogonal Regression (EFOR) algorithm, is proposed to select such a common model structure. Two examples are presented to illustrate the application and the effectiveness of the new identification approach

Main Street, Marion, and Miscegenation: The Warren Harding Race Rumor and the Social Construction of Race and Marriage

In the final weeks of the 1920 presidential election campaign, an eccentric college professor from Ohio, William Estabrook Chancellor, distributed a series of leaflets across the Midwest that claimed the Republican candidate and future president, Warren G. Harding, was racially “impure.” Much has been written about Chancellor, his racist theories, which were based on the “scientific racism” of the time, and his relationship to the Democratic Party. What has not been examined, however, is how his allegations about Harding were connected broadly to the social construction of whiteness in America in the twentieth century. In this context, the Harding race rumor is not at all a marginal moment in the history of the twenty-ninth president. Rather, it helps to show that Warren Harding\u27s experience with the race dichotomy of the early twentieth century had much in common with that of other persons accused of mixed-race status at the time. Harding\u27s extended family members were put under severe risk of being discredited and disenfranchised in a nation where it only took a hint of white racial “impurity” to deprive a person of the privileges of whiteness. As such, there is ample reason to reconsider the ways we remember Warren Harding\u27s life and presidenc

Evaluating Precipitation Features and Rainfall Characteristics in a Multi-scale Modeling Framework

Cloud and precipitation systems over the tropics and subtropics are simulated with a multi-scale modeling framework (MMF) and compared against the TRMM radar precipitation features (RPFs) product. A methodology, in close analogy to the TRMM RPFs, is developed to analyze simulated cloud precipitating structures from the embedded two-dimensional cloud-resolving models (CRMs) within an MMF. Despite the two-dimensionality of the CRMs, the simulated RPFs population distribution, and horizontal and vertical structure are in good agreement with TRMM observations. However, some deficits are also found in the model simulations. The model tends to overestimate mean convective precipitation rates for RPFs with a size less than 100 km, contributing to the excessive precipitation biases in the warm pool and western Pacific, western and northern India Ocean, and eastern Pacific commonly found in most MMFs. For large features with a size greater than 150 km, both convective and stratiform rain rates are underestimated. The distribution of maximum radar echo top heights as a function of RPF size is well simulated except the model tends to underestimate the occurrence frequency of maximum heights greater than 15 km. The maximum echo top heights for convective cells embedded within large RPFs with a size greater than 150 km are also underestimated. The cyclic lateral boundary with a limited model domain generates artificial occurrences for RPFs with a size close to the model domain size, producing a significant contribution to the total rainfall due to their sizes. This cyclic lateral boundary effect can be easily identified and quantified in both probability and cumulative distribution functions of RPFs. The geophysical distribution of the population of the largest RPFs in the control experiment shows they are mainly located in the Subtropics but also partially contribute to the common MMF biases of excessive precipitation in the Tropics. Sensitivity experiments using CRMs with different domain sizes and different grid spacings show larger domains (higher resolution) tend to shift the RPFs distribution to large (small) sizes. The cyclic lateral boundary biases increase as CRM domain size decreases. The impacts of model horizontal and vertical resolution on simulated convective systems are also investigated

Assessment of the impact of the Economic Partnership Agreement between the ECOWAS countries and the European Union

The present study consists of eight sections. After the introduction, we present in the first section, the profile of the ACP-EU cooperation agreements from Lomé to Cotonou. We also show how a certain “grey areas” in the WTO rules on regional agreements can enable African countries to benefit more from the EPAs by taking advantage of greater flexibility. The next section presents some graphical data on Africa’s trade flows in general and on trade flows of ECOWAS in particular. The third section deals with the analytical framework in general equilibrium. It contains a presentation of the Global Trade Analysis Project (GTAP) model used for assessing the impact of different partnership agreement options. In the fourth section, we focus on the characteristics of African economies, which are drawn from the GTAP database and which play a key role in the operative interactions in this kind of liberalization. The fifth section deals with the analytical framework in partial equilibrium which is complementary to the general-equilibrium modelling. The assessments of the economic impacts of the EPAs for Africa, using the general-equilibrium model, are analysed in the sixth section, while those particularly concerning the ECOWAS countries, using the partial-equilibrium framework, are presented in the penultimate section. Finally, the last section comprises concluding remarks.EPA-European Union-Africa-Trade Policy

Assessment of the Impact of the Economic Partnership Agreement between the COMESA countries and the European Union

The purpose of this study, is to evaluate possible economic repercussions of the trade facet, in Economic Partnership Agreements (EPAs), currently being negotiated between countries of the Common Market in Eastern and Southern Africa (COMESA) and Member-States of European Union (EU). In so-doing, we have used two complementary models, the first one, based-on a general equilibrium approach, and the second, a partial equilibrium method. Indeed, multilateral trade agreements, will have implications trade activities, on the production of goods and factors, the price of consumer-goods, on the are of specialization of national economies, and their productive structure. Existing trade policy instruments also, will have direct and indirect effects on the market value of goods produced locally, or imported onto the markets of the COMESA sub-region.EPA-European Union-COMESA

Can Market Access Help African Agriculture?

This paper examines the implications for African economies of the possible outcomes from the ongoing agriculture negotiations in the Doha Round. The paper defines scenarios that capture key elements of the modalities negotiations and undertakes simulations using a global dynamic general equilibrium model to examine the impact of multilateral agricultural trade reforms on African economies. The scenarios vary in their level of ambition in the market access pillar through both the level of tariff cuts in the different tiers and the level of sensitive sectors defined both for developed and developing economies. Results show that ambitious coefficients in the market access pillar remain the best outcome for Africa. Even what might seem to be an insignificant definition of sensitive products for developed countries erodes potential benefits from deep tariff cuts for African countries. This suggests that utilizing sensitive products tariff lines by developed countries not only dampens the expected positive outcomes for agriculture negotiations in favour of Africa but could also actually wipe out such gains. The results further confirm findings of other studies showing that tariff cuts for agricultural goods yield higher gains than elimination of subsidies, and this applies mainly to net food importing developing countries. Thus, reduction of subsidies should go hand-in-hand with agricultural tariff reductions in order to ensure win-win outcomes.Agriculture in International Trade, Welfare Economics, Computable General Equilibrium, Models, Africa

Economic and Welfare Impacts of the EU-Africa Economic Partnership Agreements

Th is study examines the economic and social impacts of the trade liberalization aspects of the proposed Economic Partnership Agreements (EPAs) between the European Union (EU) and African countries. It provides a quantitative assessment of the likely implications of EPAs establishing Free Trade Areas (FTAs) between the EU and the various African Regional Economic Communities (RECs). Th e focus of the empirical analysis is on the trade liberalization component of the EPAs. In particular, the following questions are addressed. First, how will an EPA that includes reciprocal market access agreements between the EU and Africa impact on African countries’ GDPs, levels of employment and other macroeconomic aggregates? Second, what sectors in Africa are most likely to lose and what sectors gain with EPAs? Th ird, what are the welfare implications for African countries from the EPAs? Fourth, how will the formation of EPAs aff ect trade expansion through trade creation and trade diversion eff ects? Fifth, what are the potential fi scal implications of the EPAs? Th e main conclusions drawn from the results and the discussions are that full reciprocity will be very costly for Africa irrespective of how the issue is looked at. A focus on deepening integration with a view to enhancing intra-African trade would provide positive results. But it is the scenario that off ers unrestricted market access for Africa, which deals eff ectively with barriers associated with sensitive European products, that portends the largest gain for the continent. Even with reciprocity, a free trade area that includes sectors of export interest to Africa and one that deals with non-tariff barriers promises positive results for African countries.EPA- Africa- Europe

Insights into the origin of metazoan filopodia and microvilli.

Filopodia are fine actin-based cellular projections used for both environmental sensing and cell motility, and they are essential organelles for metazoan cells. In this study, we reconstruct the origin of metazoan filopodia and microvilli. We first report on the evolutionary assembly of the filopodial molecular toolkit and show that homologs of many metazoan filopodial components, including fascin and myosin X, were already present in the unicellular or colonial progenitors of metazoans. Furthermore, we find that the actin crosslinking protein fascin localizes to filopodia-like structures and microvilli in the choanoflagellate Salpingoeca rosetta. In addition, homologs of filopodial genes in the holozoan Capsaspora owczarzaki are upregulated in filopodia-bearing cells relative to those that lack them. Therefore, our findings suggest that proteins essential for metazoan filopodia and microvilli are functionally conserved in unicellular and colonial holozoans and that the last common ancestor of metazoans bore a complex and specific filopodial machinery

X-ray fluoresced high-Z (up to Z = 82) K-x-rays produced by LiNbO3 and LiTaO3 pyroelectric crystal electron accelerators

High-energy bremsstrahlung and K X-rays were used to produce nearly background-free K X-ray spectra of up to 87 keV (Pb) via X-ray fluorescence. The fluorescing radiation was produced by electron accelerators, consisting of heated and cooled cylindrical LiTaO3 and LiNbO3 crystals at mTorr pressures. The newly discovered process of gas amplification whereby the ambient gas pressure is optimized to maximize the electron energy was used to produce energetic electrons which when incident on a W/Bi target gave rise to a radiation field consisting of high-energy bremsstrahlung as well as W and Bi K X-rays. These photons were used to fluoresce Ta and Pb K X-rays.Comment: 6 pages, 6 figures, PD