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Medicine and Health Sciences

Selected Works

Selected Works

1991

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Reconstruction And Future Trends Of The Aids Epidemic In The United States, Ron Brookmeyer Nov 1991

Reconstruction And Future Trends Of The Aids Epidemic In The United States, Ron Brookmeyer

Ron Brookmeyer

There has been considerable uncertainty in estimates of past and current human immunodeficiency virus (HIV) infection rates in the United States. Statistical estimates of historical infection rates can be obtained from acquired immunodeficiency syndrome (AIDS) incidence data and the incubation period. However, this approach is subject to a number of sources of uncertainty and two other approaches, epidemic models of HIV transmission and surveys of HIV prevalence, are used to corroborate and refine the statistical estimates. Analyses suggest the HIV infection rate in the United States grew rapidly in the early 1980s, peaked in the mid-1980s, and subsequently declined markedly. …

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Madagascar: Island Of Ghosts, Nat Quansah Sep 1991

Madagascar: Island Of Ghosts, Nat Quansah

Nat Quansah

No abstract provided.

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Solving Ill-Posed Problems With Artificial Neural Networks, Arun D. Kulkarni Dec 1990

Solving Ill-Posed Problems With Artificial Neural Networks, Arun D. Kulkarni

Arun Kulkarni

With many physical problems, measurement of spectral distribution, cosmic radiation, aerial and satellite imaging indirect sensing/recording devices are used. In many of these cases, the recording systems can be modeled by a Fredholm integral equation of the first kind. An inversion of the kernel representing a system, in the presence of noise, is an ill-posed problem. The direct inversion often yields an unacceptable solution. In this paper, we suggest an artificial neural network (ANN) architecture to solve certain kinds of ill-posed problems. The weights in the model are initialized using eigen-vectors and eigen-values of the kernel matrix that characterize the …

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