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Challenges for Japanese universities' technology licensing offices: What technology transfer in the United States can tell us
American universities have been transferring their technology to industry since before World War II. This technology is now developed with the more than 1 Billion in royalty payments, create hundreds of new start-up companies every year, and are the recipients of more than 3400 US patents. Most of the royalties are paid for biomedical and pharmaceutical ["bio" and "pharma"] research, with these funding companies usually insisting on and obtaining exclusive intellectual property [IP] rights. As a pure business model, this process is somewhat questionable for the universities, but the other benefits obtained by the universities and society more than compensate for the costs. This paper will address US technology transfer from the viewpoint of an industrial "customer" - IBM - and from the viewpoint of my consulting company that represents universities and companies in technology transfer. From this experience we will identify some challenges facing newly "privatized" Japanese universities and propose some suggestions to Japanese Technology Licensing Offices [TLO] for what we believe are "best practices" in technology transfer
Quantum Quenches in Free Field Theory: Universal Scaling at Any Rate
Quantum quenches display universal scaling in several regimes. For quenches
which start from a gapped phase and cross a critical point, with a rate slow
compared to the initial gap, many systems obey Kibble-Zurek scaling. More
recently, a different scaling behaviour has been shown to occur when the quench
rate is fast compared to all other physical scales, but still slow compared to
the UV cutoff. We investigate the passage from fast to slow quenches in scalar
and fermionic free field theories with time dependent masses for which the
dynamics can be solved exactly for all quench rates. We find that renormalized
one point functions smoothly cross over between the regimes.Comment: 40 pages; v2: a bit late, but it includes minor modifications to
match published versio
Smooth and fast versus instantaneous quenches in quantum field theory
We examine in detail the relationship between smooth fast quantum quenches,
characterized by a time scale , and {\em instantaneous quenches},
within the framework of exactly solvable mass quenches in free scalar field
theory. Our earlier studies \cite{dgm1,dgm2} highlighted that the two protocols
remain distinct in the limit because of the relation
of the quench rate to the UV cut-off, i.e., always holds
in the fast smooth quenches while for instantaneous
quenches. Here we study UV finite quantities like correlators at finite spatial
distances and the excess energy produced above the final ground state energy.
We show that at late times and large distances (compared to the quench time
scale) the smooth quench correlator approaches that for the instantaneous
quench. At early times, we find that for small spatial separation and small
, the correlator scales universally with , exactly as in
the scaling of renormalized one point functions found in earlier work. At
larger separation, the dependence on drops out. The excess energy
density is finite (for finite ) and scales in a universal fashion
for all . However, the scaling behaviour produces a divergent result in the
limit for , just as in an instantaneous
quench, where it is UV divergent for . We argue that similar results
hold for arbitrary interacting theories: the excess energy density produced is
expected to diverge for scaling dimensions .Comment: 52 pages; v2: minor modifications to match published versio
An exactly solvable quench protocol for integrable spin models
Quantum quenches in continuum field theory across critical points are known
to display different scaling behaviours in different regimes of the quench
rate. We extend these results to integrable lattice models such as the
transverse field Ising model on a one-dimensional chain and the Kitaev model on
a two-dimensional honeycomb lattice using a nonlinear quench protocol which
allows for exact analytical solutions of the dynamics. Our quench protocol
starts with a finite mass gap at early times and crosses a critical point or a
critical region, and we study the behaviour of one point functions of the
quenched operator at the critical point or in the critical region as a function
of the quench rate. For quench rates slow compared to the initial mass gap, we
find the expected Kibble-Zurek scaling. In contrast, for rates fast compared to
the mass gap, but slow compared to the inverse lattice spacing, we find scaling
behaviour similar to smooth fast continuum quenches. For quench rates of the
same order of the lattice scale, the one point function saturates as a function
of the rate, approaching the results of an abrupt quench. The presence of an
extended critical surface in the Kitaev model leads to a variety of scaling
exponents depending on the starting point and on the time where the operator is
measured. We discuss the role of the amplitude of the quench in determining the
extent of the slow (Kibble-Zurek) and fast quench regimes, and the onset of the
saturation.Comment: 54 pages, 13 figures; v2: added analytic argument for Kitaev mode
Synthesis of timed circuits using BDDs*
Journal ArticleThis paper presents a tool which synthesizes timed circuits from reduced state graphs. Using timing information to reduce state graphs can lead to significantly smaller and faster circuits. The tool uses implicit techniques (binary decision diagrams) to represent these graphs. This allows us to synthesize larger, more complex systems which may be intractable with an explicit representation. We are also able to create a parameterized family of solutions, facilitating technology mapping
New verification method for embedded systems
Journal ArticleAbstract-Verification of embedded systems is complicated by the fact that they are composed of digital hardware, analog sensors and actuators, and low level software. In order to verify the interaction of these heterogeneous components, it would be beneficial to have a single modeling formalism that is capable of representing all of these components. To address this need, this paper describes an extended labeled hybrid Petri net (LHPN) model that includes constructs for Boolean, discrete, and continuous variables as well as constructs to model timing. This paper also presents a method to verify these extended LHPNs. Finally, this paper presents a case study to illustrate the application of this model to the verification of a fault-tolerant temperature sensor
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