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63.
Typical random codes (TRCs) in a communication scenario of source coding with side information in the decoder is the main subject of this work. We study the semi-deterministic code ensemble, which is a certain variant of the ordinary random binning code ensemble. In this code ensemble, the relatively small type classes of the source are deterministically partitioned into the available bins in a one-to-one manner. As a consequence, the error probability decreases dramatically. The random binning error exponent and the error exponent of the TRCs are derived and proved to be equal to one another in a few important special cases. We show that the performance under optimal decoding can be attained also by certain universal decoders, e.g., the stochastic likelihood decoder with an empirical entropy metric. Moreover, we discuss the trade-offs between the error exponent and the excess-rate exponent for the typical random semi-deterministic code and characterize its optimal rate function. We show that for any pair of correlated information sources, both error and excess-rate probabilities exponential vanish when the blocklength tends to infinity. 相似文献
64.
The synthesis of two oligomers, of a bifunctional diketopiperazine scaffold DKP-1, formally derived from the cyclization of l-aspartic acid and (S)-2,3-diaminopropionic acid, is reported. A trimeric and a tetrameric structure were prepared by solution-phase peptide synthesis (Boc strategy). Conformational analysis of these derivatives was carried out by a combination of 1H NMR spectroscopy, CD spectroscopy, and molecular modeling, and revealed the formation of β-bend ribbon involving 10-membered H-bonded rings and a reverse turn of the growing peptide chain. 相似文献
65.
Umberto M. Battisti Marina M. Carrozzo Carlo Parenti Luigino Troisi 《Tetrahedron letters》2010,51(33):4433-4436
A simple and efficient synthetic path for N-1 or N-2 alkyl-substituted 2-aminobenzenesulfonamides was developed based on regioselective reduction with NaBH3CN in different solvents. 相似文献
66.
Umberto Casellato Rodolfo Graziani Giuseppe Maccarrone Angel J. di Bilio 《Journal of chemical crystallography》1986,16(5):695-702
cis-Diaquabis(2,2-bipyridyl)chromium(III) nitrate crystallizes in the mono-clinic system, space groupP21/c, witha=16.102(6),b=10.792(5),c=15.076(6) Å,=112.90(5)°, andZ=4. The saltlike structure was determined from X-ray crystallography and refined toR=7.5% for 3342 observed reflections. The Cr atom is octahedrally surrounded by twocis water molecules and by two chelated 2,2-bypiridyl ligands forming two nearly orthogonal planes. Selected bond distances are: Cr-O, 2.00(1) and 1.98(1) Å, Cr-N, 2.04 Å (mean). 相似文献
67.
Rosa IL Filho PC Neri CR Serra OA de Figueiredo AT Varela JA Longo E 《Journal of fluorescence》2011,21(4):1575-1583
This work reports on the synthesis and characterization of a new complex of Eu3+ with the 3-hydroxypicolinamide ligand (Hhpa). Here we present an approach for obtaining bis[2-carbamoyl(κO)pyridin-3-olato(κO’)]
lanthanide complexes, which were characterized through elemental analysis, thermal analysis, infrared and photoluminescence
spectroscopies (emission, excitation, luminescence lifetimes, quantum efficiencies, Judd-Ofelt parameters and quantum yields).
Although hpa can act as a bidentate ligand in different conformations, the results attest for the occurrence of a unique coordination
site of low symmetry for the Eu3+ ions, in which two anionic hpa ligands coordinate the cations through an O/O chelating system. The phosphorescence of the
synthesized gadolinium complex provides the energy of the triplet state, which is determined to be at 20,830 cm-1 over the ground state. This makes the Hhpa ligand very adequate for sensitizing the Eu3+ luminescence, which leads to a very efficient antenna effect and opens a wide range of applications for the complex in light
emitting organic-inorganic devices. 相似文献
68.
We study the totally asymmetric simple exclusion process (TASEP) on complex networks, as a paradigmatic model for transport subject to excluded volume interactions. Building on TASEP phenomenology on a single segment and borrowing ideas from random networks we investigate the effect of connectivity on transport. In particular, we argue that the presence of disorder in the topology of vertices crucially modifies the transport features of a network: irregular networks involve homogeneous segments and have a bimodal distribution of edge densities, whereas regular networks are dominated by shocks leading to a unimodal density distribution. The proposed numerical approach of solving for mean-field transport on networks provides a general framework for studying TASEP on large networks, and is expected to generalize to other transport processes. 相似文献
69.
P. M. Ossi F. Neri N. Santo S. Trusso 《Applied Physics A: Materials Science & Processing》2011,104(3):829-837
Silver and gold thin films were deposited by pulsed laser ablation in a controlled Ar atmosphere at pressures between 10 and
100 Pa. Different morphologies, ranging from isolated nanoparticle arrays up to nanostructured thin films were observed. Fast
imaging of the plasma allowed deducing the expansion dynamics of the ablated plume. Plasma velocity and volume were used together
with the measured average ablated mass per pulse as input parameters in a model to estimate the average size of nanoparticles
grown in the plume. The nanoparticle size is expected to decrease from 4 nm down to 1 nm with decreasing Ar pressure between
100 and 10 Pa: this was confirmed by transmission electron micrographs which indicate a reduced dispersion of particle size
over narrow size ranges. The production of substrates for surface enhanced Raman scattering whose performances critically
depend on nanoparticle size, shape, and structure is discussed. 相似文献
70.
Alberto Bolognesi Paolo DiGianvincenzo Umberto Giovanella Raniero Mendichi Alberto Giacometti Schieroni 《European Polymer Journal》2008,44(3):793-800
The control of the organization of polymeric films from the nano- to the meso-scale is an ongoing field and different approaches have been proposed by many authors with the aim to drive the organization and the morphology of the materials to optimize their properties. One of the driving force of the organization at the micrometric and submicrometric scale is the degree of interaction between different polymeric chains and many successful examples of ordered supramolecular organization based on nano and microphase separation have been reported by using block copolymers and polymer blends. In this work we report on a synthetic approach to prepare a copolymeric structure formed by polystyrene and 3,4-ethylenedioxythiophene (EDOT) oligomers with the aim of preparing thin polymeric films exhibiting organized morphologies. 相似文献