On the (non)existence of best low-rank approximations of generic IxJx2 arrays

Several conjectures and partial proofs have been formulated on the (non)existence of a best low-rank approximation of real-valued IxJx2 arrays. We analyze this problem using the Generalized Schur Decomposition and prove (non)existence of a best rank-R approximation for generic IxJx2 arrays, for all values of I,J,R. Moreover, for cases where a best rank-R approximation exists on a set of positive volume only, we provide easy-to-check necessary and sufficient conditions for the existence of a best rank-R approximation

A Century of Brickmaking at Berlin Junction: A History of the Alwine Brick Company

The Alwine family name had been associated with brickmaking in York and Adams Counties at least since the early 1850s, when Peter Samuel Alwine started his first brickyard on a farm in Paradise Township of York County.1 He learned the trade of brickmaking during his youth and by the age of seventeen had become a skilled artisan. He learned how to make bricks by working in the spring and summer months at a brickmaking operation in Peach Bottom Township, located in the southeastern corner of York County. He did not set up his own brickyard until later, and following his marriage to Catharine Dahlhammer in 1860, he moved his brickmaking facilities to the farm where they settled in Paradise Township, near the Borough of Berwick (now Abbottstown) in Adams County. During that time, Mr. Alwine also engaged for varying periods as a schoolteacher, country merchant, and farmer. Later, he established a brickyard at Spring Grove in York County, and eventually another at Berlin Junction, near New Oxford in Adams County. Over the years, he attained a reputation as a man of considerable learning and sound business judgment. After his death, in 1895, his sons William and Lewis Alwine continued the business under the name Alwine Brothers Brickyard, and later William’s son Charles Emory Alwine would become president of the firm. Following Charles Alwine’s retirement, and three generations of Alwine leadership, ownership of the company was transferred in 1978 to the Glen-Gery Corporation of Reading. This article chronicles the history of the Alwine Brick Company from its beginnings to its final years, including more than a century at Berlin Junction, Adams County, Pennsylvania. [excerpt

The marginated pool

The pulmonary circulation harbors a large intravascular reservoir of leukocytes refered to as the Marginated Pool. This marginated pool is balanced by propeling and retaining forces acting on leukocytes during their passage through the pulmonary circulation. The present paper discusses these factors and their underlying mechanisms. Copyright (C) 2002 S. Karger AG, Basel

Drought impacts and related risk management by smallholder farmers in developing countries: evidence from Awash River Basin, Ethiopia

Climate risk studies have largely neglected household coping and adaptation strategies. In this paper we analyze drought impacts, drought risk management, and resulting drought resilience in Awash River Basin of Ethiopia based on socio-economic data collected from 43 randomly selected Peasant Associations. We find that severe drought periods have led to a significant depression of crop yields and to widespread death of livestock in the past. Drought periods have drastically increased the proportion of food insecure households and lengthened the duration of food insecurity in the area. Since, with climate change, drought periods are predicted to become more frequent in this region in the future, the problem of food insecurity is likely to become even more severe. Ex-ante adaptation strategies are widely practised in Awash River Basin and include the storage of crop residues as fodder for livestock, the rearing of drought tolerant livestock, mixed cropping, the use of short duration crop varieties, and the adoption of soil and water conservation practices. Ex-post coping strategies utilized to manage the consequences of drought include the sale of assets and the reliance on consumption loans and support offered by informal networks. Therefore, suitable policies are urgently needed to strengthen farmers’ capacity to adapt to and cope with drought. Training farmers in the production and conservation of livestock fodder as well as in soil and water conservation practices appear to be key policy options relevant in the area. Moreover, improving farmers’ access to climate related information, especially drought forecasts, could improve the timely adoption of effective adaptation measures.drought, drought risk management, Ethiopia, Environmental Economics and Policy, Production Economics, O13, Q12,

The aim remains: Monetary union

No doubt the monetary measures taken by the Government of the Federal Republic on May 10 have caused quite a stir. The question is: Can the European economic and monetary union still be achieved, in spite of the German measures