一个新奇的无条件安全的量子密码分发协议

提出了一个基于纠缠交换理论犤2～4犦的量子密钥分发协议。安全性分析证明此QKD协议是无条件安全,而且十分有效。     

Composition of the surface waxes from bell pepper and eggplant

Surface waxes from the skins of bell pepper (Capsicum annuum) and eggplant (Solanum melongena) were rinsed with tert-butylmethyl ether (TBME). The wax components were separated into two fractions by elution from a small silica gel column with toluene/hexane (2+1) followed by methanol. They were identified by GC/MS and quantitatively determined by GC/FID. For 12 bell pepper cultivars, fraction 1 made up 39% of the total and contained mainly n-alkanes C₂₀–C₃₅ (with C₃₁ dominating), iso-alkanes C₂₅–C₃₅, and some aldehydes. The 61% of fraction 2 consisted of 15 triterpenes, namely - and -amyrin, lupeol, glutinol, 3-friedelanol, friedelin, taraxerol, taraxasterol, -amyrin, germanicol, multiflorenol, -taraxasterol, isomultiflorenol, isobauerenol and bauerenol, as well as n-alkanoic acids C₁₆–C₃₂, 2-hydroxy-alkanoic acids C₂₀–C₂₆ and traces of n-alkanols and phytosterols (campesterol, stigmasterol and -sitosterol). For the three eggplant cultivars, 77% of fraction 1 was obtained with (in decreasing order) n-alkanes C₂₃–C₃₆, anteiso-alkanes C₂₉–C₃₆, iso-alkanes C₂₇–C₃₅, and some aldehydes. In the 23% of fraction 2, the n-alkanoic acids C₁₆–C₃₂ predominated compared with the 2-hydroxy-alkanoic acids C₂₂–C₂₆, the n-alkanols C₂₄–C₂₉, triterpenols (- and -amyrin, lupeol, germanicol) and sterols (stigmasterol and -sitosterol).     

Software project management audits

This paper shows how project audits can be used to uncover project strengths and weaknesses. Three audits are described and findings of the audit teams are summarized. Audits helped identify organizational problems, lacking management discipline, and software testing approaches useful to other projects. The issue of product sales versus disciplined project management was faced in all three audits. How this issue was handled is discussed and related to the success or lack of it for each project.     

Pectin methylesterase catalyzed firming effects on low temperature blanched vegetables

The effect of low temperature blanching on firmness of eight vegetables was studied. Preheating vegetables at low temperatures prior to a conventional blanch resulted in firmer products. Temperature and time had significant effects on texture, with temperature the most influential. Under optimal conditions, firmness improvements in preheated vegetables as compared to blanched controls were: Bok choy—3.0 × (65 °C, 45 min); Chinese cabbage—1.8 × (55 °C, 45 min); cabbage—1.6 × (65 °C, 15 min); green bell peppers—1.36 × (70 °C, 15 min); sugar snap peas—1.7 × (65 °C, 30 min); carrots—2.1 × (60 °C, 15 min) and broccoli—2.9 × (60 °C, 15 min). Thermal stability and optimal temperature for pectin methylesterase in homogenates from these vegetables were also analyzed. The relationship between optimum preheating conditions for textural integrity and pectin methylesterase activity is discussed.     

用分组神经网络识别手写体数字

用神经网络识别手写体数字,大多数采用的是单个的神经网络结构.本文给出一个基于特征输入的手写体数字识别的分组神经网络结构,它是一个混合网络(Hybrid System).实验的结果表明,同只采用单个神经网络结构的方法相比,分组网络具有更好的识别结果.     

关于有限群的超可解性

本文证明了定理1 设G为群,则W_∞(G)=SI(G) 定理2 设G为群,N■G,若G/N超可解且N的素数阶元均属于W_∞(G),则G超还解的充要条件是G与T_(2q)无关。     

基于量子克隆的二面体群隐含子群问题量子算法的研究

基于最短向量问题的格公钥密码体制是典型的抗量子计算密码体制。格的唯一最短向量问题可转化为二面体群的隐含子群问题。有效地求解二面体群的隐含子群问题可攻破基于格的唯一最短向量问题的公钥密码体制。Kuperberg提出了二面体群隐含子群问题的半指数级量子算法。通过研究Kuperberg量子算法,利用概率量子克隆,文中提出了二面体群隐含子群问题的多项式时间量子算法。     

2~4p阶群的类型(Ⅰ)——p为奇素数,且Sylow子群正规

本文用群论的理论和方法研究2~4p阶群的分类。给出了Sylow子群正规时所有2~4p群的定义关系。     

二端口电网络元件体系研究

用群论研究了二端口电网络元件体系中各元件集合的群关系.结果表明,二端口电网络元件集合之间存在子群与陪集关系,并且证明了构成陪集集合的元件能生成构成子群集合的元件,从而确定了二端口有源回转器和二端口反照器是二端口电网络的基本元件.