1,885 research outputs found
Shortest Unique Substring Query Revisited
We revisit the problem of finding shortest unique substring (SUS) proposed
recently by [6]. We propose an optimal time and space algorithm that can
find an SUS for every location of a string of size . Our algorithm
significantly improves the time complexity needed by [6]. We also
support finding all the SUSes covering every location, whereas the solution in
[6] can find only one SUS for every location. Further, our solution is simpler
and easier to implement and can also be more space efficient in practice, since
we only use the inverse suffix array and longest common prefix array of the
string, while the algorithm in [6] uses the suffix tree of the string and other
auxiliary data structures. Our theoretical results are validated by an
empirical study that shows our algorithm is much faster and more space-saving
than the one in [6]
An FBAR Circulator
This letter presents the experimental demonstration of a film bulk acoustic
resonator (FBAR) circulator at 2.5 GHz. The circulator is based on
spatio-temporal modulation of the series resonant frequency of FBARs using
varactors and exhibits a large isolation of 76 dB at 2.5 GHz. The FBAR chip
(0.25 mm2) consists of three identical FBARs connected in wye configuration.
The FBAR0s quality factor (Q) of 1250 and piezoelectric coupling coefficient kt
2 of 3% relaxes the modulation requirements, achieving non-reciprocity with
small modulationto- RF frequency ratio bettter than 1:800 (3 MHz:2.5 GHz)
Two-sided matching via balanced exchange: Tuition and worker exchanges
We introduce a new matching model to mimic two-sided exchange programs such as tuition and worker exchange, in which each firm has to avoid being a net-exporter of workers. These exchanges use decentralized markets, making it difficult to achieve a balance between exports and imports. We show that stable equilibria discourage net-exporting firms from exchange. We introduce the two-sided top-trading-cycles mechanism that is balanced-efficient, worker-strategy-proof, acceptable, and individually rational, and respects priority bylaws regarding worker eligibility. We prove that it is the unique mechanism fulfilling these objectives. Moreover, it encourages exchange, since full participation is the dominant strategy for firms
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