σ-LFSR序列极小多项式性质研究

σ-线性反馈移位寄存器(σ-LFSR)是基于字设计的,在安全性和效率上达到较好折衷的一种反馈移位寄存器.σ-LFSR输出序列的特征多项式为有限域上的矩阵多项式.该文利用有限域上矩阵多项式环的代数结构,给出了σ-LFSR输出序列极小多项式唯一的充分必要条件.     

本原σ-LFSR序列的迹表示及其应用

σ-LFSR是一基于字的LFSR模型,它的设计充分利用了现代CPU特点,可很好地应用于设计适合快速软件实现的序列密码算法中。而在实际应用中,本原σ-LFSR序列具有最核心的作用。该文分析了本原σ-LFSR序列的产生条件,利用其迭代关系式和有限域的迹函数,给出了它的具体表达式,从而得到本原σ-LFSR序列的迹表示;其次由本原σ-LFSR序列的迹表示,给出了一个σ-LFSR序列为本原的充要条件。它们为进一步研究本原σ-LFSR序列提供了新的工具。     

σ-LFSR序列极小多项式性质研究

σ-线性反馈移位寄存器(σ-LFSR)是基于字设计的,在安全性和效率上达到较好折衷的一种反馈移位寄存器。σ-LFSR输出序列的特征多项式为有限域上的矩阵多项式。该文利用有限域上矩阵多项式环的代数结构,给出了σ-LFSR输出序列极小多项式唯一的充分必要条件。     

本原σ-LFSR序列距离向量的计算

证明了本原σ-线性反馈移位寄存器(σ-LFSR)序列距离向量的计算与有限域上离散对数的计算等价,同时给出一个本原σ-LFSR序列距离向量的计算方法。还给出一类特殊本原σ-LFSR序列距离向量的计算方法,该方法将有限域上离散对数的计算转化到其子域上离散对数的计算,复杂度显著降低。     

本原a-LFSR序列的迹表示及其应用

-LFSR是一基于字的LFSR模型,它的设计充分利用了现代CPU特点,可很好地应用于设计适合快速软件实现的序列密码算法中.而在实际应用中,本原-LFSR序列具有最核心的作用.该文分析了本原-LFSR序列的产生条件,利用其迭代关系式和有限域的迹函数,给出了它的具体表达式,从而得到本原-LFSR序列的迹表示;其次由本原-LFSR序列的迹表示,给出了一个-LFSR序列为本原的充要条件.它们为进一步研究本原-LFSR序列提供了新的工具.     

基于距离向量的本原σ-LFSR序列研究

距离向量是本原σ-LFSR序列的重要参数,但目前关于距离向量的研究还很少。该文基于距离向量,首先证明了m=2时采样猜想是正确的,然后对本原σ-LFSR的采样性质进行了研究,最后给出了Z本原σ-LFSR序列和本原σ-LFSR序列新的构造方法。     

本原σ-LFSR序列的线性复杂度研究

线性复杂度是衡量密钥流序列安全性的重要参数。该文考察了有限域上n级本原σ-LFSR序列的线性复杂度性质。首先得到了它的上下界并证明了界是紧致的,然后利用序列的根表示给出了计算本原σ-LFSR序列线性复杂度的方法。     

基于LFSR高次剩余问题构造公钥密码体制的研究

该文对用线性反馈移位寄存器(LFSR)构造公钥密码体制做了进一步的研究,定义了LFSR的高次(非)剩余问题,基于新的困难问题探讨了构造一种加解密不同于GH的密码原型,并给出了具体的加解密过程,证明了它的可行性;在此基础上,进一步把该体制改进为概率加密体制,克服了GH加密确定性的缺点,同时对体制的安全性和效率做了初步分析,具有单向性和语意安全性,最后证明了该体制的单向性等价于LFSR高次剩余问题,语意安全性等价于LFSR判断高次剩余问题。     

基于随机性测试的SNOW 2.0算法部件分析与改进

SNOW族算法是目前序列密码算法设计的一个主流方向。针对SNOW族算法现有的安全漏洞,该文以最具代表性的SNOW 2.0算法为研究对象,采用随机性测试方法对其多个域上模加、非线性S盒以及线性反馈移位寄存器(LFSR)3个核心部件进行分析,提出基于随机S盒和高性能LFSR等部件改进的多套改进方案,有效提升SNOW族算法的安全性和实现性能。     

基于全体圈个数为4的LFSR构造de Bruijn序列的研究

为了提高并圈法的构造效率,拓宽并圈法的应用深度,从圈结构中圈个数的角度,提出了基于全体圈个数为4的LFSR构造de Bruijn序列的方法。基于LFSR的级联特征,确定了一类级联型的反馈移位寄存器的圈结构,并据此给出了圈个数为4的n级LFSR的精确个数,以及基于全体圈个数为4的n级LFSR构造n级de Bruijn序列的全部数目。     

电源纹波对放大器频率稳定度的影响

本文定量地分析了晶体管高频调谐放大器中直流稳压电源的纹波给放大器输出信号增添的相位起伏。并在此基础上建立了对应于这种相位起伏的以时畴阿仑方差2y()表征的频率稳定度的计算公式。     

Fluctuations of the laser characteristics and the effect of theindex-coupling component in the gain-coupled DFB laser

The normalized oscillation frequency δL and threshold gain αL of gain-coupled distributed feedback (DFB) lasers with an AR/AR (symmetric) structure vary significantly with a variation in the corrugation phase at the facets when the facet reflectivity |r| is large, even though the spatial-hole-burning-corrected yield is 100%. For example, the standard deviation for the δL, σ(δL), increases from 0.018 to 0.40 when |r| is increased from 0.03 to 0.30. The magnitude of σ(δL) and σ(αL) are small, however, for the gain-coupled, index-coupled, and complex-coupled DFB lasers when the |r| is kept small. For the HR/AR (asymmetric) structure, these two values are more than an order of magnitude larger than those for the AR/AR structure, except for the σ(αL) for the index-coupled laser, even though yields of each of these lasers are relatively large. In the AR/AR structure, the contamination by the index-coupling and gain-coupling components always degrades the device characteristics because of the difference in the phase shifter and when the amount of contamination is small this degradation is particularly severe for the index-coupled laser. Several properties of the index-coupled laser with the HR/AR structure can be improved, however, by introducing the gain-coupling component     

A binary analog to the entropy-power inequality

Let {X_n}, {Y_n} be independent stationary binary random sequences with entropy H( X), H(Y), respectively. Let h(ζ)=-ζlogζ-(1-ζ)log(1-ζ), 0⩽ζ⩽1/2, be the binary entropy function and let σ(X)=h^-1 (H(X)), σ(Y)=h^-1 (H(Y)). Let z_n=X_n⊕Y_n , where ⊕ denotes modulo-2 addition. The following analog of the entropy-power inequality provides a lower bound on H(Z ), the entropy of {Z_n}: σ(Z)⩾σ(X)*σ(Y), where σ(Z)=h^-1 (H(Z)), and α*β=α(1-β)+β(1-α). When {Y _n} are independent identically distributed, this reduces to Mrs. Gerber's Lemma from A.D. Wyner and J. Ziv (1973)     

Self‐assembled Cationic Peptide Nanoparticles Capable of Inducing Efficient Gene Expression In Vitro

In this study, cationic and amphiphilic oligopeptides, (A)₁₂(H)₅(K)₁₀ (AK27) and (A)₁₂(H)₅(K)₁₅ (AK32), were designed and tested as a nonviral gene vector. The oligopeptides had critical micelle concentrations (CMC) of 0.9 and 1.1 mg mL^?1 respectively, indicating that they were able to self‐assemble into core–shell nanoparticles at concentrations above the CMC value, which was confirmed by electron microscopy. The nanoparticles were cubic and had an effective diameter of 700–900 nm, as well as a zeta potential of 18 to 20 mV. The formation of nanoparticles increased the local concentration of cationic charge in the solution, leading to improved DNA binding ability and better protection from enzymatic degradation compared to the control peptide (H)₅(K)₁₀ (HK15) without a hydrophobic block. The smallest effective diameters of AK27–DNA and AK32–DNA complexes were 442 and 332 nm, respectively, and the highest zeta potentials were 7.8 and 18.2 mV, respectively. In comparison, HK15 formed much larger DNA complexes with a nearly neutral zeta potential. Cytotoxicity tests showed that HEK293, HepG2, and 4T1 cell lines had viabilities of more than 80% after incubation with AK27 and AK32 peptides, which was much higher than that obtained from polyethyleneimine (PEI) incubation. Furthermore, an increased length of lysine block, and the presence of the hydrophobic block did not show any significant increase in cytotoxicity. More importantly, AK27 and AK32–DNA complexes induced much higher luciferase expression efficiency than KH15 in all three cell lines tested. AK32 with a longer lysine block led to more efficient gene expression than AK27. In addition, the gene‐expression levels mediated by AK32 nanoparticles were comparable to those provided by PEI, especially in HepG2 and 4T1 cell lines. These cationic nanoparticles made from biodegradable and biocompatible peptides may provide a promising carrier for gene delivery.     

Solution processed single-emissive-layer white organic light-emitting diodes based on fluorene host: Balanced consideration for color quality and electroluminescent efficiency

Cost-effective fabrication of white organic light-emitting diodes (WOLED) is meaningful toward commercial application of environment-friendly solid-state lighting sources. Electroluminescent efficiency and color quality are two opposite performance characteristics facing solution processed WOLEDs requiring balanced consideration. Herein, a recently synthesized molecule of 4,4’-(9,9’-(1,3-phenylene)bis(9H-fluorene-9,9-diyl))bis(N,N-diphenylaniline) (DTPAFB) is introduced as a host material for solution processed all-phosphor WOLEDs, embracing four well-known molecules which are blue iridium (III) bis(2-(4,6-difluorophenyl)pyridinato-N,C²)(picolinate) (FIrpic), green iridium (III) bis[2-(2-pyridinyl-N)phenyl-C](2,4-pentanedionato-O²,O⁴) [Ir(ppy)₂(acac)], and orange iridium (III) bis(2-phenyl-benzothiazole-C²,N)(acetylacetonate) [Ir(bt)₂(acac)] plus a home-made red phosphor of iridium (III) tris(1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine) [Ir(MPCPPZ)₃]. Illumination quality white light with high brightness, high efficiency, suitable correlated color temperature (CCT), high color-rendering index (CRI), and stable electroluminescent (EL) emission is obtained. A stable white emission with a CRI over 70, Commission Internationale de L'Eclairage (CIE) of (0.37, 0.42), and high EL efficiency of 19.6 lm W⁻¹ at high luminance of 2000 cd m⁻² for blue/orange complementary color WOLEDs is demonstrated. The optimized red/green/blue three primary color WOLEDs show improved CRI up to 81, moderate high efficiency of 25.8 cd A⁻¹, 14.4 lm W⁻¹, and EQE of 13.9%. Furthermore, the red/green/blue/orange four primary color WOLEDs show the optional balance between color quality and EL efficiency with high CRI of around 81–83 and medium CCT of 3755–3929 K which is warm and soft to human eyes. At an illumination relevant luminance of 1000 cd m⁻², the total power efficiency reaches 33.6 lm W⁻¹, and still remains 30.2 lm W⁻¹ at 3000 cd m⁻², approaching the efficiency of state-of-the-art fluorescent-tube (40–70 lm W⁻¹), potentially suitable as an environment-friendly solid-state lighting source. This work indicates that developing high performance host materials and highly efficient phosphors and carefully combining them with common phosphors is an effective way toward high performance WOLEDs.     

Highly efficient near-infrared emission from binuclear cyclo-metalated platinum complexes bridged with 5-(4-octyloxyphenyl)-1,3,4-oxadiazole-2-thiol in PLEDs

A novel near-infrared-emitting binuclear platinum complex of (piq)₂Pt₂(μ-C₈OXT)₂ was synthesized and characterized, in which piq is 1-phenylisoquinolinato and C₈OXT is a bridging ancillary ligand of 5-(4-octyloxyphenyl)-1,3,4-oxadiazole)-2-thiol. Its optophysical, electrochemical and electroluminescent characteristics were primary studied. This binuclear platinum complex exhibited an intense UV absorption at about 493 nm from the metal–metal-to-ligand charge transfer transition and a bright near-infrared emission at 721 nm in chloromethane. Using (piq)₂Pt₂(μ-C₈OXT)₂ as a single dopant, its single-emissive-layer polymer light-emitting devices presented a high-efficiency near-infrared emission peaked at 702 nm with the maximum external quantum efficiency of 6.3% at 7.6 mA cm^?2. This work provides an efficient approach to realize high-efficiency near-infrared emission by binuclear platinum complexes.