6,382 research outputs found
Improved Inner Approximation for Aggregating Power Flexibility in Active Distribution Networks and its Applications
Concise and reliable modeling for aggregating power flexibility of
distributed energy resources in active distribution networks (ADNs) is a
crucial technique for coordinating transmission and distribution networks. Our
recent research has successfully derived an explicit expression for the exact
aggregation model (EAM) of power flexibility at the substation level under
linearized distribution network constraints. The EAM, however, is impractical
for decision-making purposes due to its exponential complexity. In this paper,
we propose an inner approximation method for aggregating flexibility in ADNs
that utilizes the properties of the EAM to improve performance. Specifically,
the geometric prototype of the inner approximation model is defined according
to a subset of the coefficient vector set of the EAM, which enhances the
accuracy. On the other hand, the computation efficiency of the inner
approximation is also significantly improved by exploiting the regularity of
coefficient vectors in the EAM in the parameter calculation process. The inner
approximated flexibility model of ADNs is further incorporated into the
security-constrained unit commitment problem as an application. Numerical
simulations verify the effectiveness of the proposed method.Comment: 10 page
Decoy State Quantum Key Distribution With Modified Coherent State
To beat PNS attack, decoy state quantum key distribution (QKD) based on
coherent state has been studied widely. We present a decoy state QKD protocol
with modified coherent state (MCS). By destruction quantum interference, MCS
with fewer multi-photon events can be get, which may improve key bit rate and
security distance of QKD. Through numerical simulation, we show about 2-dB
increment on security distance for BB84 protocol.Comment: 4 pages, 4 figure
(3S,12R,20S,24R)-20,24-Epoxydammarane-3,12,25-triol
In the title molecule, C30H52O4, the three six-membered rings are in chair conformations, the cyclopentane ring is in an envelope form and the tetrahydrofuran ring has a conformation intermediate between half-chair and sofa. In the crystal, molecules are linked by intermolecular O—H⋯O hydrogen bonds into helical chains along [100]. Two intramolecular O—H⋯O hydrogen bonds are also present. One C atom of the tetrahydrofuran ring and its attached H atoms are equally disordered over two sets of sites
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