The Dimension of Subcode-Subfields of Shortened Generalized Reed Solomon Codes

Reed-Solomon (RS) codes are among the most ubiquitous codes due to their good parameters as well as efficient encoding and decoding procedures. However, RS codes suffer from having a fixed length. In many applications where the length is static, the appropriate length can be obtained by an RS code by shortening or puncturing. Generalized Reed-Solomon (GRS) codes are a generalization of RS codes, whose subfield-subcodes are extensively studied. In this paper we show that a particular class of GRS codes produces many subfield-subcodes with large dimension. An algorithm for searching through the codes is presented as well as a list of new codes obtained from this method

Subfield-Subcodes of Generalized Toric codes

We study subfield-subcodes of Generalized Toric (GT) codes over $\mathbb{F}_{p^s}$. These are the multidimensional analogues of BCH codes, which may be seen as subfield-subcodes of generalized Reed-Solomon codes. We identify polynomial generators for subfield-subcodes of GT codes which allows us to determine the dimensions and obtain bounds for the minimum distance. We give several examples of binary and ternary subfield-subcodes of GT codes that are the best known codes of a given dimension and length.Comment: Submitted to 2010 IEEE International Symposium on Information Theory (ISIT 2010

Effect of the hard magnetic inclusion on the macroscopic anisotropy of nanocrystalline magnetic-materials

It is shown that the presence of highly anisotropic magnetic precipitates in a soft multiphased matrix can produce a remarkable hardening, even when the volume fraction of the precipitates is small. The exchange coupling between the matrix and the precipitates is the relevant parameter. In particular, the simplified analysis we develop in this paper accounts for the magnetic hardening observed in very soft Fe-rich nanocrystals after annealing at higher temperatures

Universal angular magnetoresistance and spin torque in ferromagnetic/normal metal hybrids

The electrical resistance of ferromagnetic/normal-metal (F/N) heterostructures depends on the nature of the junctions which may be tunnel barriers, point contacts, or intermetallic interfaces. For all junction types, the resistance of disordered F/N/F perpendicular spin valves as a function of the angle between magnetization vectors is shown to obey a simple universal law. The spin-current induced magnetization torque can be measured by the angular magnetoresistance of these spin valves. The results are generalized to arbitrary magnetoelectronic circuits

From Digital to Analogue Magnetoelectronics: Theory of Transport in Non-Collinear Magnetic Nanostructures

Magnetoelectronics is mainly digital, i.e. governed by up and down magnetizations. In contrast, analogue magnetoelectronics makes use of phenomena occuring for non-collinear magnetization configurations. Here we review theories which have recently been applied to the transport in non-collinear magnetic nanostructures in two and multiterminal structures, viz. random matrix and circuit theory. Both are not valid for highly transparent systems in a resistive environment like perpendicular metallic spin valves. The solution to this problem is a renormalization of the conventional and spin-mixing conductance parameters.Comment: To be published in "Advance in Solid State Physics", edited by B. Kramer, Springer Verlag, Berlin, 200

Tracking Event Model

This note presents the LHCb Tracking Event Model. It discusses the requirements and motivations and the subsequent choices that lead to the final implementation. The event model classes and tools as in software versions Brunel v30r17, LHCb v21r12, Lbcom v5r9 and Rec v3r14 are described; these versions were used for the physics production of the 2006 data challenge (DC06)

Extra-EU Imports of Clothing and EU Preferential Trade Policies in the Post-Quota Era: The Position of Asian Suppliers in the Largest World Market for Clothing Imports

The European Union (EU) became the largest single market for clothing imports in 2007, surpassing the United States (US). This paper examines the competitive position of suppliers from developing Asia in the expanded EU clothing market relative to other non-EU suppliers, including those receiving preferences under the complex system of EU preferential trade programs. The paper finds that competitive Asian suppliers, led by the People's Republic of China (PRC), have performed well in the EU clothing market since quotas were eliminated under the Agreement on Textiles and Clothing (ATC) in 2005. It also examines price movements in imported clothing under the ATC (2004) and after quotas were abolished (2005), and then examines how the imposition of safeguards on the PRC (2006–2007) affected prices. The relative position of various groups of suppliers in terms of unit prices is then compared with the PRC and the world as a whole. Finally, time trends in price movements are examined for the PRC and from all suppliers. The findings indicate that the end of quotas on the PRC on 1 January 2008 should bring renewed downward pressure on prices in the EU clothing market, and will require other suppliers to become more efficient, else they lose market share

Price Dynamics in the US Market for Apparel Imports: Impact of Quota Elimination under the Agreement on Textiles and Clothing and Safeguard Restrictions on the People's Republic of China

C. Peter Timmer writes about the causes of high food prices, focusing on staple grains - rice in particular - and edible oils. He shows that although food prices have come down from the spikes of early 2008, they are likely to remain higher than they were in early 2007 for years to come. The paper explores the implications for policy and includes a technical appendix that provides the analytical framework of this analysis