包含缺省的Z规约演化:一种可操作的方法

对于软件系统的需求工程,需求演化至关重要。目前,对此问题已有不少基于逻辑的解决方法。但我们认为,它们并没有提供足够丰富的元逻辑,来全面地刻画这个问题的各个方面。本文基于开放逻辑和 Brewka 缺省理论,提出了 Z 规约演化的一种可操作的方法,使之能刻画该问题的各个方面。并通过一个案例研究,证明其有效性。国家重点基础研究发展规划(973)项

Isospectral Molecule

[中文文摘]本文根据HG的约化、变形和交替烃的图形方法,建立了一种研究分子同谱性质的有效图解法。应用图解法可以直观、简便地判断同谱分子,并能直接找出一个HG的同谱点和无约束点,构造出共轭分子的同谱图。这种图形方法又使Herndon等人提出的判断同谱点和无约束点方法得到群理论根据。[英文文摘]Based upon the reduction and transformation of Huckel graph and the graphical method of AH, an effetive diagrammatic method for the study of the cospectral properties of conjugated molecules is established in this paper. The application of this graphical method gives a judgment for the study of isospectral molecules in a simple and direct manner, and provides a direct method for the determination of isospectral points and unrestricted points on Huckel graph, and consequently, provides a method for construct the isospectral graphy of the conjugated molecules.Moreover,this graphical method provides a group theoretical interpretation of Herndon's criteria for the isospectral points and unrestrieted points

Graphical Methods of the MO Theory of AH

[中文文摘]本文把交替烃分子轨道成对定理推广到类二色图的约化HG,从而统一了二元均杂共轭体系与其等共轭体系的分子轨道计算,并利用有星标图形和无星标图形,提出交替烃分子轨道图解法,进一步简化了交替烃的HMO计算。[英文文摘]In this article we extend the pairing theorem of the MO theory of AH to the bicolorable reduced Huckel graph, and also unify the MO calculations of the conjugated system composed of alternating groups and that of its corresponding isoconjugate system. In addition, fay the usse of starred and unstarrcd graph, a graphical method of the MO method of AH is proposed, and HMO calculations of AH can be further simplified

Graphical Method of π-Electron Energy Spectrum with Conjugation in Straight Chain Molecule oS Polymer

[中文文摘]对于直链共轭高聚物分子π电子能谱的HMO计算,本文根据一个近似的计算模型,即把这类分子看作具有C_∝轴对称性的共轭体系,使之可利用C_K铀对称性约化共轭体系的Huckel图形(HG),从而迅速、直观地计算一些典型直链共轭高聚物分子的π电子能谱。[英文文摘]Based Upon an approximate mode for the HMO calculations of π-electron energy spectrum with conjugation in straight, chain molecule of polymer, these conjugated molecules may be considered as a conjugated system with C∞ rotation symmetry, and then, by the use of the C∞ rotation symmetry for the reduction of the HuCkel graph, the π-electron energy spectrum of the conjugated polymer can be calculated readily and directly

基于交互式马尔可夫链的模型检验

研究了基于交互式马尔可夫链(IMC)的模型检验,IMC是集功能描述和性能刻画为一体的并发系统模型,模型检验是一种自动功能验证与性能评价技术。文中提出的模型检验算法结合了传统的功能验证与性能评价的功能,并且与现有的算法相一致。实验分析表明,该算法具有较高的性能,适用于大型复杂系统的验证和评价

Synthesis and Antibacterial Activity of Trans-but-2-enedioic Acid Bis-aromatic Alcohol Ester

本文合成了一系列的反丁烯二酸芳香醇(苄醇、苯乙醇、苯丙醇、邻溴苄醇)酯,所得产物的NMR、FTIR表征结果与理论预测一致。用光电比浊法研究其抑菌活性,反丁烯二酸芳香醇酯表现出较强的抑菌活性,随着芳香醇的链长的增加对四种细菌的抑制作用也增强,芳香醇卤代后,与反丁烯二酸所生成的二酯的抑菌作用也得到加强。反丁烯二酸芳香醇酯有望成为高效抑菌剂。A series of trans-but-2-enedioic acid bis-aromatic alcohol ester have been firstly synthesized by direct reaction of trans-but-2-enedioic acid with aromatic alcohol. The products were characterized with 1H NMR and FTIR. All the characterization data are consistent with the theoretic compositions and structures. The antibacterial activities against Bacillus subitilis,Mycococcus tetragenus Krasil' nikov,Staphylococcus aureus and Escherichia coli were tested by the method of phototurbidometry. All of the derivatives showed strong antibacterial activity against bacteria tested. The antibacterial activities of the derivatives were more effective with longer chain of the aromatic alcohol and halogenated with halide. It showed that the derivatives are potent and promising antibacterial agents

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

We present a measurement of the integrated luminosity e+e- of collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm = 3.773 GeV. The integrated luminosities of the datasets taken from December 2021 to June 2022, from November 2022 to June 2023, and from October 2023 to February 2024 were determined to be 4.995±0.019 fb-1, 8.157±0.031 fb-1, and 4.191±0.016 fb-1, respectively, by analyzing large angle Bhabha scattering events. The uncertainties are dominated by systematic effects, and the statistical uncertainties are negligible. Our results provide essential input for future analyses and precision measurements