2,885 research outputs found
Miriam Levin, neice of Dr. Friedrich Foerster, with her husband Dr. J. Levin Portraits Couples
No full textPhotograph found in book donated to LBI library by Alex Natan (AR 11349)Dr. Friedrich Foerster saved the life of (Alex Natan?) at Budzyn (near Kraśnik, Poland)Digital Imag
Miriam Levin, neice of Dr. Friedrich Foerster, with her husband Dr. J. Levin Portraits Couples
No full textPhotograph found in book donated to LBI library by Alex Natan (AR 11349)Dr. Friedrich Foerster saved the life of (Alex Natan?) at Budzyn (near Kraśnik, Poland)Digital Imag
Spectral Sparsification in the Semi-Streaming Setting
No full textLet G be a graph with n vertices and m edges. A sparsifier of G is a sparse graph on the same vertex set approximating in some natural way. It allows us to say useful things about while considering much fewer than m edges. The strongest commonly-used notion of sparsification is spectral sparsification; H is a spectral sparsifier of G if the quadratic forms induced by the Laplacians of G and H approximate one another well. This notion is strictly stronger than the earlier concept of combinatorial sparsification.
In this paper, we consider a semi-streaming setting, where we have only ~O(n) storage space, and we thus cannot keep all of G. In this case, maintaining a sparsifier instead gives us a useful approximation to G, allowing us to answer certain questions about the original graph without storing all of it. In this paper, we introduce an algorithm for constructing a spectral sparsifier of G with O(n log n/epsilon^2) edges (where epsilon is a parameter measuring the quality of the sparsifier), taking ~O(m) time and requiring only one pass over G. In addition, our algorithm has the property that it maintains at all times a valid sparsifier for the subgraph of G that we have received.
Our algorithm is natural and conceptually simple. As we read edges of we add them to the sparsifier . Whenever gets too big, we resparsify it in time. Adding edges to a graph changes the structure of its sparsifier's restriction to the already existing edges. It would thus seem that the above procedure would cause errors to compound each time that we resparsify, and that we should need to either retain significantly more information or reexamine previously discarded edges in order to construct the new sparsifier. However, we show how to use the information contained in to perform this resparsification using only the edges retained by earlier steps in nearly linear time
Improved Spectral Sparsification and Numerical Algorithms for SDD Matrices
No full textWe present three spectral sparsification algorithms that, on input a graph G with n vertices and m edges, return a graph H with n vertices and O(n log n/epsilon^2) edges that provides a strong approximation of G. Namely, for all vectors x and any epsilon>0, we have (1-epsilon) x^T L_G x n log^5 n and runs in tilde{O}(m log_{m/ n log^5 n} n time. In the range where m>n^{1+r} for some constant r this becomes softO(m). The improved sparsification algorithms are employed to accelerate linear system solvers and algorithms for computing fundamental eigenvectors of dense SDD matrices
sj-docx-1-jvb-10.1177_0145482X231169294 - Supplemental material for An Innovative Interprofessional Course in Ophthalmology and Low Vision for Occupational Therapy Students
No full textSupplemental material, sj-docx-1-jvb-10.1177_0145482X231169294 for An Innovative Interprofessional Course in Ophthalmology and Low Vision for Occupational Therapy Students by Alison Bell, Lucas Bonafede, Arlene Lorch, Melanie Snitzer, Scott A. Edmonds, and Alex V. Levin in Journal of Visual Impairment & Blindness</p
Sustaining volcanism in central Kamchatka
No full textFlux-induced melting in the mantle wedge acts as the driving mechanism of arc volcanism in subduction zone environments. The primary control on the geographical position of arc volcanic centers is the depth of the subducting plate beneath the overriding plate. Globally, the average depth to the subducting plate beneath volcanic arcs is estimated at ~100km. Volcanoes of the Central Kamchatka Depression in Eastern Russia comprise the most active volcanic arc system in the world with the depth of the subducting Pacific plate beneath the arc estimated at 180-200km, greatly in excess of the global average. In my research I attempt to describe the special tectonic circumstances that explain the deviation of the subduction depth constraint on arc volcanism in Central Kamchatka. In my study I rely on geophysical and geochemical data and petrological modeling to propose a new geodynamic model to explain voluminous volcanic activity in Central Kamchatka. In the initial stage of the study I conducted a geophysical investigation using receiver function methodology to map and describe the contact of the subducting Juan de Fuca Plate in the well-instrumented Cascadia subduction zone. I calculated and compiled a database of receiver function profiles from stations along the extent of the Cascadia forearc and mapped a low velocity anisotropic zone proposed to be serpentinized material along the forearc axis. In the second stage of my study I applied a similar methodology to describe the sub-crustal structure of Central Kamchatka. Results of this effort suggested presence of a low-velocity zone in the upper mantle separate from the subducting Pacific plate. I proceeded to investigate the tectonic origin of this feature in the final stage of my dissertation work with the use of receiver function migration, geochemical analysis and petrological modeling. I was able to further constrain the position of the low velocity anomaly and derive geochemical and petrological evidence linking the anomaly to a second source of melting driving volcanism of the Central Kamchatka arc.Ph. D.Includes bibliographical referencesby Alex Nikuli
"The Consolidated Assistance Program, Reforming Welfare by Synchronizing Public Assistance Benefits"
No full textLevin-Waldman examines the structure of existing welfare programs and concludes that the current array of benefits could be synchronized and consolidated to create a new system that would provide economic incentives to work. He suggests combining elements of the earned income tax credit (EITC) and current welfare programs into one program, a consolidated assistance program (CAP). Levin-Waldman argues that a program composed of an assistance component (with one set of benefits for working parents and a different set for nonworking parents) and a child support component could be designed to assure minimal subsistence to those unable to work while providing incentives for those on welfare to work without, in effect, penalizing them for getting off welfare. Such a program would reform welfare more expeditiously than a plan that would simply expand the EITC or put a time limit on welfare benefits. Moreover, such a plan would not necessarily add to the national budget deficit.
Development of the Zimbabwe family planning program
No full textFamily planning was introduced in Zimbabwe as a voluntary movement in the 1950s. Volunteers formed a Family Planning Association in the mid-1960s. The government became interested in family planning in the late 1960s after analysis of the 1961 population census. It gave the Family Planning Association an annual grant, allowed contraceptives to be available through Ministry of Health facilities, and allowed nonmedical personnel to initiate and resupply family planning clients with condoms and pills. But before Zimbabwe achieved independence in 1980, family planning was viewed with great suspicion by the black majority, so the program's effectiveness was limited to the urban few. A new era began after independence. The new government took over theFamily Planning Association and changed its outlook completely. Through government and international donor support, the family planning program was restructured and expanded. The number of family planning personnel more than doubled in some units. More service delivery points were set up - particularly in rural areas. And the information, education, and communication and evaluation and research units were established. Through a World Bank-assisted project (with grant funding from Norway and Denmark), the Ministry of Health began strengthening its family planning capabilities. These efforts helped increase the contraceptive prevalence rate from about 14 percent in 1982 to 43 percent in 1988. But the program's growth is beginning to stall. More effort and resources are needed if the program is to grow or even maintain its present status. Particularly important are the following: designing innovative strategies to reach hard-to-reach populations; giving more emphasis to information, education, and communication, especially for men and youths, using multimedia; involving other sectors in the delivery of family planning services; broadening the mix of contraceptive methods (especially promoting long-term and permanent methods); making use of alternative family planning delivery systems, such as the use of depot holders, volunteers, and government extension workers; establishing a national population policy; and considering cost recovery and other measures for self-sustainment and program growth.Agricultural Knowledge&Information Systems,ICT Policy and Strategies,Gender and Health,Health Monitoring&Evaluation,Adolescent Health
Head of Schmarya Levin (1867-1935) 20th century
No full textThe sitter was a Russian-born writer and Zionist. Signed and numbered 2/25 in lower left.Mrs. Zeno Darmstadter, New York.Digital imageDr. Schmarya Levin (1867-1935) was a well-known author and Zionist leader
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