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31.
We give generic constructions of several fundamental cryptographic primitives based on a new encryption primitive that combines circular security for bit encryption with the so-called reproducibility property (Bellare et al. in Public key cryptography—PKC 2003, vol. 2567, pp. 85–99, Springer, 2003). At the heart of our constructions is a novel technique which gives a way of de-randomizing reproducible public-key bit encryption schemes and also a way of reducing one-wayness conditions of a constructed trapdoor function family (TDF) to circular security of the base scheme. The main primitives that we build from our encryption primitive include k-wise one-way TDFs (Rosen and Segev in SIAM J Comput 39(7):3058–3088, 2010), chosen-ciphertext-attack-secure encryption and deterministic encryption. Our results demonstrate a new set of applications of circularly secure encryption beyond fully homomorphic encryption and symbolic soundness. Finally, we show the plausibility of our assumptions by showing that the decisional Diffie–Hellman-based circularly secure scheme of Boneh et al. (Advances in cryptology—CRYPTO 2008, vol. 5157, Springer, 2008) and the subgroup indistinguishability-based scheme of Brakerski and Goldwasser (Advances in cryptology—CRYPTO 2010, vol. 6223, pp. 1–20, Springer, 2010) are both reproducible.  相似文献   
32.

An eight-channel wavelength demultiplexer by cascading of ring resonators (RRs) in photonic crystal (PhC) structure is proposed in this paper. In designing of this demultiplexer, we used eight square-shaped PhC RRs with different refractive index (RI) of defect rods to generate a distinctive resonance wavelength. Each PhC RR has a specific resonance wavelength with tuning a variety of design parameters such as RI of a whole, defect and inner rods and radius of defect rods. In operating wavelength of λ0?=?1497 nm, the transmission power and quality factor (Q) of single RR are discovered as 96% and 1000, respectively. The average power transmission, channel spacing, crosstalk and full width at half maximum are found by finite difference time domain method to be about 96?±?1%, 2.25 nm, ??35 dB and 1.5 nm, respectively. Simulation outcomes demonstrate that the designed demultiplexer has a proper operation. The footprint of the designed device is about?~?115 μm2, which makes this device a promising for future photonic integrated circuits.

  相似文献   
33.
Antigens incorporated in subunit vaccines are typically poorly immunogenic, so a strong immunostimulant (adjuvant) and/or delivery system is required to boost immunogenicity. In this work, the various functional polymer nanostructures, that is, rods, worms, spheres, and tadpoles are used to develop potent peptide antigen delivery systems. The antigen PADRE-J8 (PJ8), derived from Group A Streptococcus (GAS) M-protein, is either physically mixed or chemically conjugated to polymeric nanoparticles of different shapes. The physical mixture of polymeric nanoparticles and antigen is more effective in inducing antibody production than their chemical conjugates. Moreover, rod-shaped polymeric nanoparticles in physical mixture with PJ8 elicited higher and more opsonic antibody titers than powerful complete Freund's adjuvant (CFA)-adjuvanted antigen. Herein, for the first time it is demonstrated that a) the block copolymer, in nanoparticle form, can act as an immune adjuvant, b) nanoparticle shape plays a crucial role in their immunogenicity, and c) antigen conjugation is not required, nor is antigen encapsulation or absorption.  相似文献   
34.
Telecommunication Systems - Interference is the main source of capacity limitation in wireless networks. In some medium access technologies in cellular networks, such as OFDMA, the allocation of...  相似文献   
35.
Wireless Networks - In order to satisfy the delay requirements of telecommunication systems, in this paper, we present a cooperative network with the short packet transmission in the Rayleigh...  相似文献   
36.
In this paper, a hybrid method is proposed for multi-channel electroencephalograms (EEG) signal compression. This new method takes advantage of two different compression techniques: fractal and wavelet-based coding. First, an effective decorrelation is performed through the principal component analysis of different channels to efficiently compress the multi-channel EEG data. Then, the decorrelated EEG signal is decomposed using wavelet packet transform (WPT). Finally, fractal encoding is applied to the low frequency coefficients of WPT, and a modified wavelet-based coding is used for coding the remaining high frequency coefficients. This new method provides improved compression results as compared to the wavelet and fractal compression methods.  相似文献   
37.
The S-transform presents arbitrary time series as localized invertible time–frequency spectra. This transformation improves the short-time Fourier transform and the wavelet transform by merging the multiresolution and frequency-dependent analysis properties of wavelet transform with the absolute phase retaining of Fourier transform. The generalized S-transform utilizes a combination of a Fourier transform kernel and a scalable-sliding window. The common S-transform applies a Gaussian window to provide appropriate time and frequency resolution and minimizes the product of these resolutions. However, the Gaussian S-transform is unable to obtain uniform time and frequency resolution for all frequency components. In this paper, a novel window based on the $t$ student distribution is proposed for the S-transform to achieve a more uniform resolution. Simulation results show that the S-transform with the proposed window provides in comparison with the Gaussian window a more uniform resolution for the entire time and frequency range. The result is suitable for applications such as spectrum sensing.  相似文献   
38.
All-d Heuslers are a category of novel compounds combining versatile functionalities such as caloric responses and spintronics with enhanced mechanical properties. Despite the promising transport properties (anomalous Hall (AHC) and anomalous Nernst (ANC) conductivities) shown in the conventional Co2XY Heuslers with p-d hybridization, the all-d Heuslers with only d-d hybridization open a new horizon to search for new candidates with outstanding transport properties. In this work, the AHC and ANC are evaluated for thermodynamically stable ferro/ferri-magnetic all-d-metal regular Heusler compounds based on high-throughput first-principles calculations. It is observed that quite a few materials exhibit giant AHCs and ANCs, such as cubic Re2TaMn with an AHC of 2011 S cm-1, and tetragonal Pt2CrRh with an AHC of 1966 S cm-1 and an ANC of 7.50 A m-1K-1. Comprehensive analysis on the electronic structure reveals that the high AHC can be attributed to the occurrence of the Weyl nodes or gapped nodal lines in the neighborhood of the Fermi level. The correlations between such transport properties and the number of valence electrons are also thoroughly investigated, which provides a practical guidance to tailor AHC and ANC via chemical doping for transverse thermoelectric applications.  相似文献   
39.
40.
Novel direct designs for 3-input exclusive-OR (XOR) function at transistor level are proposed in this article. These designs are appropriate for low-power and high-speed applications. The critical path of the presented designs consists of only two pass-transistors, which causes low propagation delay. Neither complementary inputs, nor V DD and ground exist in the basic structure of these designs. The proposed designs have low dynamic and short-circuit power consumptions and their internal nodes dissipate negligible leakage power, which leads to low average power consumption. Some effective approaches are presented for improving the performance, voltage levels, and the driving capability and lowering the number of transistors of the basic structure of the designs. All of the proposed designs and several classical and state-of-the-art 3-input XOR circuits are simulated in a realistic condition using HSPICE with 90 nm CMOS technology at six supply voltages, ranging from 1.3 V down to 0.8 V. The simulation results demonstrate that the proposed circuits are superior in terms of speed, power consumption and power-delay product (PDP) with respect to other designs.  相似文献   
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