A CLASS OF SEPARABILITY FLEXIBLE FUNCTIONAL FORMS

Quadratic flexible forms, such as the translog and generalized Leontief, are separability inflexible. That is, separability restrictions render them inflexible with regard to separable structures. A class functional forms is proposed that is flexible with regard to general production structures and remains flexible regarding weakly separable structures when separability restrictions are imposed, thus permitting tests of the separability hypothesis. Additionally, the restricted forms are parsimonious; that is they contain the minimum number of parameters with which flexibility can be achieved.Research Methods/ Statistical Methods,

Herdís & Ólína: The Poetry of Everyday Life

The twin sisters Herdís Andrésdóttir and Ólína Andrésdóttir were born on the island Flatey in Breiðafjörður, western Iceland, in 1858. Following the death of their father at sea three years later, the family was dispersed and the sisters did not see each other until half a century later, when they were reunited in Reykjavík. In the intervening years both sisters had become well known as capable verse-makers in the traditional style, but it had never, it seems, occurred to them to write any of their poems down, let alone publish them. They were encouraged by friends to do so, and in 1924 they brought out a collection of their verse, entitled simply Ljóðmæli (Poems). Their poetry was highly traditional both in its form, which principally made use of rímur and ballad metres, and in terms of its subject matter, dealing with nature, reflections on life’s joys and sorrows and so on. Ólína, like her cousin Theodóra Thoroddsen, also contributed to the revival of the þula, a form of poetry traditionally associated with children. The book sold well, and a second edition, with some additional poems, came out in 1930. A third edition was brought out in 1976, long after their deaths, containing much new material; this edition has since been reprinted twice. Critical reception was overwhelmingly favourable, both in the learned and more popular press. Though somewhat at odds with the literary establishment of the day, they nevertheless had several powerful supporters among the literary and intellectual élite, foremost among them professor Sigurður Nordal. Despite having been “world-famous in Iceland” in their old age, Herdís and Ólína are little known today, and their work – much of it very fine indeed – has yet to receive the scholarly attention it deserves

MIT LMFBR blanket research project. Quarterly progress report, July 1, 1975--September 30, 1975

Research progress on physics experiments and calculations for LMFBR breeding blankets is briefly reported. (JWR

Strong Pinning Enhancement in MgB2 Using Very Small Dy2O3 Additions

0.5 to 5.0 wt.% Dy2O3 was in-situ reacted with Mg + B to form pinned MgB2. While Tc remained largely unchanged, Jc was strongly enhanced. The best sample (only 0.5 wt.% Dy2O3) had a Jc of 6.5 x 10^5 A/cm^2 at 6K, 1T and 3.5 x 10^5 A/cm^2 at 20K, 1T, around a factor of 4 higher compared to the pure sample, and equivalent to hot-pressed or nano-Si added MgB2 at below 1T. Even distributions of nano-scale precipitates of DyB4 and MgO were observed within the grains. The room temperature resistivity decreased with Dy2O3 indicative of improved grain connectivity.Comment: 13 pages, 4 figures and 1 tabl

An assessment of internal blankets for gas-cooled fast reactors

Originally presented as first author's thesis (Ph. D.--Massachusetts Institute of Technology), 1980Includes bibliographical references (pages 338-346)Sponsored by General Atomic Compan

Fast Dynamic Graph Algorithms for Parameterized Problems

Fully dynamic graph is a data structure that (1) supports edge insertions and deletions and (2) answers problem specific queries. The time complexity of (1) and (2) are referred to as the update time and the query time respectively. There are many researches on dynamic graphs whose update time and query time are $o(|G|)$, that is, sublinear in the graph size. However, almost all such researches are for problems in P. In this paper, we investigate dynamic graphs for NP-hard problems exploiting the notion of fixed parameter tractability (FPT). We give dynamic graphs for Vertex Cover and Cluster Vertex Deletion parameterized by the solution size $k$. These dynamic graphs achieve almost the best possible update time $O(\mathrm{poly}(k)\log n)$ and the query time $O(f(\mathrm{poly}(k),k))$, where $f(n,k)$ is the time complexity of any static graph algorithm for the problems. We obtain these results by dynamically maintaining an approximate solution which can be used to construct a small problem kernel. Exploiting the dynamic graph for Cluster Vertex Deletion, as a corollary, we obtain a quasilinear-time (polynomial) kernelization algorithm for Cluster Vertex Deletion. Until now, only quadratic time kernelization algorithms are known for this problem. We also give a dynamic graph for Chromatic Number parameterized by the solution size of Cluster Vertex Deletion, and a dynamic graph for bounded-degree Feedback Vertex Set parameterized by the solution size. Assuming the parameter is a constant, each dynamic graph can be updated in $O(\log n)$ time and can compute a solution in $O(1)$ time. These results are obtained by another approach.Comment: SWAT 2014 to appea

Thin-Film Trilayer Manganate Junctions

Spin-dependent conductance across a manganate-barrier-manganate junction has recently been demonstrated. The junction is a La$_{0.67}$Sr$_{0.33}$MnO$_3$% -SrTiO$_3$-La$_{0.67}$ Sr$_{0.33}$MnO$_3$ trilayer device supporting current-perpendicular transport. Large magnetoresistance of up to a factor of five change was observed in these junctions at 4.2K in a relatively low field of the order of 100 Oe. Temperature and bias dependent studies revealed a complex junction interface structure whose materials physics has yet to be understood.Comment: 20 pages, 14 figures. To appear in Phil. Trans. R. Soc. Lond. A vol.356 (1998

Public Lands

A contribution by Howard J. Bromberg to the Encyclopedia of Global Resources

Range Queries on Uncertain Data

Given a set $P$ of $n$ uncertain points on the real line, each represented by its one-dimensional probability density function, we consider the problem of building data structures on $P$ to answer range queries of the following three types for any query interval $I$: (1) top-$1$ query: find the point in $P$ that lies in $I$ with the highest probability, (2) top-$k$ query: given any integer $k\leq n$ as part of the query, return the $k$ points in $P$ that lie in $I$ with the highest probabilities, and (3) threshold query: given any threshold $\tau$ as part of the query, return all points of $P$ that lie in $I$ with probabilities at least $\tau$. We present data structures for these range queries with linear or nearly linear space and efficient query time.Comment: 26 pages. A preliminary version of this paper appeared in ISAAC 2014. In this full version, we also present solutions to the most general case of the problem (i.e., the histogram bounded case), which were left as open problems in the preliminary versio