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31.
Carlos Ariel Gil-Barrera Raymundo Santana Carrillo Guo-Hua Sun Shi-Hai Dong 《Entropy (Basel, Switzerland)》2022,24(5)
In this work, we study the quantum information entropies for two different types of hyperbolic single potential wells. We first study the behaviors of the moving particle subject to two different hyperbolic potential wells through focusing on their wave functions. The shapes of these hyperbolic potentials are similar, but we notice that their momentum entropy densities change along with the width of each potential and the magnitude of position entropy density decreases when the momentum entropy magnitude increases. On the other hand, we illustrate the behaviors of their position and momentum entropy densities. Finally, we show the variation of position and momentum entropies and with the change of the potential well depth u and verify that their sum still satisfies the BBM inequality relation. 相似文献
32.
In this study, a novel concept of picture fuzzy threshold graph (PFTG) is introduced. It has been shown that PFTGs are free from alternating 4-cycle and it can be constructed by repeatedly adding a dominating or an isolated node. Several properties about PFTGs are discussed and obtained the results that every picture fuzzy graph (PFG) is equivalent to a PFTG under certain conditions. Also, the underlying crisp graph (UCG) of PFTG is a split graph (SG), and conversely, a given SG can be applied to constitute a PFTG. A PFTG can be decomposed in a unique way and it generates three distinct fuzzy threshold graphs (FTGs). Furthermore, two important parameters i.e., picture fuzzy (PF) threshold dimension (TD) and PF partition number (PN) of PFGs are defined. Several properties on TD and PN have also been discussed. Lastly, an application of these developed results are presented in controlling medicine resources. 相似文献
33.
Aiming at classifying the polarities over aspects, aspect-based sentiment analysis (ABSA) is a fine-grained task of sentiment analysis. The vector representations of current models are generally constrained to real values. Based on mathematical formulations of quantum theory, quantum language models have drawn increasing attention. Words in such models can be projected as physical particles in quantum systems, and naturally represented by representation-rich complex-valued vectors in a Hilbert Space, rather than real-valued ones. In this paper, the Hilbert Space representation for ABSA models is investigated and the complexification of three strong real-valued baselines are constructed. Experimental results demonstrate the effectiveness of complexification and the outperformance of our complex-valued models, illustrating that the complex-valued embedding can carry additional information beyond the real embedding. Especially, a complex-valued RoBERTa model outperforms or approaches the previous state-of-the-art on three standard benchmarking datasets. 相似文献
34.
In this review paper, we first introduce the basic concept of quantum computer-resistant cryptography, which is the cornerstone of security technology for the network of a new era. Then, we will describe the positioning of mathematical cryptography and quantum cryptography, that are currently being researched and developed. Quantum cryptography includes QKD and quantum stream cipher, but we point out that the latter is expected as the core technology of next-generation communication systems. Various ideas have been proposed for QKD quantum cryptography, but most of them use a single-photon or similar signal. Then, although such technologies are applicable to special situations, these methods still have several difficulties to provide functions that surpass conventional technologies for social systems in the real environment. Thus, the quantum stream cipher has come to be expected as one promising countermeasure, which artificially creates quantum properties using special modulation techniques based on the macroscopic coherent state. In addition, it has the possibility to provide superior security performance than one-time pad cipher. Finally, we introduce detailed research activity aimed at putting the quantum stream cipher into practical use in social network technology. 相似文献
35.
Twin-field quantum key distribution (TF-QKD) has attracted considerable attention because it can exceed the basic rate-distance limit without quantum repeaters. Its variant protocol, sending or not-sending quantum key distribution (SNS-QKD), not only fixes the security vulnerability of TF-QKD, but also can tolerate large misalignment errors. However, the current SNS-QKD protocol is based on the active decoy-state method, which may lead to side channel information leakage when multiple light intensities are modulated in practice. In this work, we propose a passive decoy-state SNS-QKD protocol to further enhance the security of SNS-QKD. Numerical simulation results show that the protocol not only improves the security in source, but also retains the advantages of tolerating large misalignment errors. Therefore, it may provide further guidance for the practical application of SNS-QKD. 相似文献
36.
桑蚕种良卵率是蚕种质量检验的重要指标,控制样本间卵粒数的偏差是保证良卵率准确性的关键。通过对桑蚕卵粒重的调查分析,得出其分布服从正态分布。若从一批蚕种中抽取1g卵作为样本,则来自同一总体的2个样本的卵粒数之差不超过16粒,其置信概率为95%;当置信概率取99%时,两个样本的卵粒数之差不超过21粒。文章为蚕业生产提供了一种实用的克卵粒数偏差控制方法。 相似文献
37.
对给定的简单图$H_1,H_2,\ldots,H_c$, 我们将使完全图$K_n$的任意边分解$\{G_i\}^c_{i=1}$都存在至少一个$G_i$有子图同构于$H_i$的最小正整数$n$称为多染色拉姆齐数 $R(H_1,H_2,\ldots,$ $H_c)$. 对正整数$m,n_1,n_2,\ldots,n_c$, 令$\Sigma=\sum_{i=1}^{c}(n_i-1)$. 在文献中,我们已经获得了$R(K_{1,n_1},\ldots,K_{1,n_c},P_m)$ 的一些界和精确值.Wang推测若$\Sigma\not\equiv 0\pmod{m-1}$且$\Sigma+1\ge (m-3)^2$, 则有$R(K_{1,n_1},\ldots, K_{1,n_c}, P_m)=\Sigma+m-1.$ 本文中, 我们给出了一个新的下界并给出$R(K_{1,n_1},\ldots,K_{1,n_c},P_m)$在$m\leq\Sigma$, $\Sigma\equiv k\pmod{m-1}$且$2\leq k \leq m-2$情况下的部分精确值. 这些结果部分证实了Wang的猜想. 相似文献
38.
By using difference schemes, orthogonal partitions and a replacement method, some new methods to construct pure quantum error-correcting codes are provided from orthogonal arrays. As an application of these methods, we construct several infinite series of quantum error-correcting codes including some optimal ones. Compared with the existing binary quantum codes, more new codes can be constructed, which have a lower number of terms (i.e., the number of computational basis states) for each of their basis states. 相似文献
39.
As a key factor leading to the pressure-dependent R1-line-shift reversal and R1-state lifetime, at 10 K, the pressure-dependent variation of mixing-degree of |t22(3T1)e4T2〉
and |t232
E〉base-wavefunctions in the wavefunction of R1 state of
LLGG:Cr3+ has been calculated and analyzed. From this, the physical origin of the pressure-dependent R1-line-shift reversal has been revealed. Furthermore, by using
the pressure-dependent values of the
sum of all square mixing-coefficients
of |t22(3T1)e4T2〉in the wavefunction of R1 state, the lifetimes of R1 state
of LLGG:Cr3+ at various pressures have been calculated, which
are in good agreement with observed results. The quantum anticrossing
effect between
t232E and t22(3T1)e4T2
levels due to both spin-orbital interaction and electron-phonon interaction is remarkable, which is related to the admixture of
|t22(3T1)e4T2〉and |t232
E〉as well as the low-high crystal-field transition. 相似文献
40.
In this paper, a quantum secure direct communication protocol using ensembles with the same density matrix is proposed. The two communication parties can realize the message transmission using this method through a quantum channel, each bit of information can be transmitted using an ensemble and read out through global measurement.The eavesdropping behavior can be detected through the channel diagnoses. 相似文献