Boris Kogan

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In cardiac fibrillation, disorganized waves of electrical activity meander through the heart, and coherent contractile function is lost. We studied fibrillation in three stationary forms: in human chronic atrial fibrillation, in a stabilized form of canine ventricular fibrillation, and in fibrillation-like activity in thin sheets of canine and human(More)
this information age it is easy to store large amounts of data electronically, but the proliferation of documents available on the web, on corporate intranets, on newswires, and elsewhere has become overwhelming. Search engines only exacerbate this by making more and more documents available in a matter of a few keystrokes. For example, the NCBI PubMed(More)
A new approach is presented for managing distributed database systems in the face of communication failures and network partitions. It offers high availability and, at the same time, guarantees some meaningful correctness properties. The approach is based on the idea of fragments and agents. It does not require prompt and correct detection of partitions and(More)
In a multilevel secure database management system based on the <italic>replicated</italic> architecture, there is a separate database management system to manage data at or below each security level, and lower level data are replicated in all databases containing higher level data. In this paper, we address the open issue of concurrency control in such a(More)
The problem of implementing reliable broadcast in ARPA-like computer networks is studied. The environment is characterized by the absence of a n y multicast facility on the communications subnetwork level. Thus, broadcast has t o be implemented directly on hosts. A reliable broadcast protocol is presented a n d evaluated by several import a n t performance(More)