The observed AGN in M87 is extremely quiescent compared to expectations based upon simple estimates for the mass accretion rate. We examine the possibility that the nal stages of accretion are advection dominated by comparing current observational constraints on the ux from the M87 core to the predictions of an advection dominated accretion ow (ADAF) model. We nd that the observed self-absorbed...

COSY 5.0 is a new computer code for the design of corpuscular optical systems based on the principle of transfer matrices . The particle optical calculations include all image aberrations through fifth order. COSY 5.0 uses canonical coordinates and exploits the symplectic condition to increase the speed of computation. COSY 5.0 contains a library for the computation of matrix elements of all co...

Association for Artificial Intelligence (AAAI) is the largest and most important meeting of AI theoreticians and practitioners in the United States This year, the conference was held in Seattle, Wash, and paid attendance was just under 5100 Last year’s Philadelphia conference drew 5400 The drop in attendance was primarily the result of competition with the International /oint Conference on Arti...

A new temporal logic and interpretation are suggested which have features from linear temporallogic, branching time temporal logic, and partial order temporaJ logic. The new logic can describe properties essential to the specification and correctness proofs of distributed algorithms such as those for global snapshots. It is alsp appropriate for the justification of proof rules and giving tempor...