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Differentiation of Four Pairs of Isomers by Comparing Their Relative Abundances of Fragment Ions

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Chemical Research in Chinese Universities 2010年第1期26卷 27-32页

作者： SUN Ming-qian LU Jian-qiu zhang Hong-gui zhang qun-shu XIAO Nan Rui-yun School of Chinese Materia Medica Beijing University of Chinese Medicine Beijing 100102 P R. China Developing Center of Science and Technique Beijing University of Chinese Medicine BeoTng 100029 P. R. China Pharmaceutical University of Shenyang Shenyang 110016 P R. China

Based on the LC-ESI/MSn technique, the four pairs of isomers of psoralen and isopsoralen, imperatorin and isoimperatorin, neohesperidin and hesperidin, naringin and narirutin were distinguished mainly by comparison of the relative abundances of their major fragment ions. Because of the effect of the hydrogen on the C8 of psoralen, the intensity of the fragment ion formed by the loss of CO2 was relatively increased. By comparing the abundance of the product ions formed by the loss of CO and 2CO, the isomers of psoralen and isopsoralen could be distinguished. This method can also be used to distinguish the isomers of imperatorin and isoimperatorin. Because of the different con- nected position between glucose and rhamnose, in the mass spectrum of neohesperidin, the relative abundances of ions at m/z 489 and 343 generated by the ring-cross cleavage of glycan were more than 10%, while in the mass spec- trum of hesperidin, they were all less than 1%. This approach can also be used to distinguish the isomers ofnaringin and narirutin. Although the fragmentation pathways were similar, according to the tiny difference of structure, the change of relative intensity of main fragment ions could be observed and it could be used to distinguish some isomers more accurately and quickly.

关键词： LC-MSn Relative abundance Isomer Product ion Generation opportunity

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改进卷积神经网络的语音情感识别方法

应用科学学报 2018年第5期36卷 837-844页

作者：曾润华张树群暨南大学信息科学技术学院广州510632

研究了基于卷积神经网络的语音情感识别算法,改进了传统卷积神经网络训练过程中的卷积核权值的更新算法,使卷积核权值的更新算法与迭代次数有关联;同时为了增加情感语音之间的特征差异性,将语音信号经过预处理后得到的梅尔频率倒谱系数... 详细信息

研究了基于卷积神经网络的语音情感识别算法,改进了传统卷积神经网络训练过程中的卷积核权值的更新算法,使卷积核权值的更新算法与迭代次数有关联;同时为了增加情感语音之间的特征差异性,将语音信号经过预处理后得到的梅尔频率倒谱系数特征数据矩阵进行变换,提高卷积神经网络的表达能力.实验表明,改进后的语音情感识别算法的错误识别率比传统算法的错误识别率约减少7%.

关键词：语音情感识别卷积神经网络梅尔频率倒谱系数识别率

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改进约束鸡群算法在神经网络的应用

计算机工程与科学 2018年第12期40卷 2252-2257页

作者：张莹杰张树群暨南大学信息科学技术学院广东广州510632

针对基本鸡群优化算法CSO存在收敛速度慢、易陷入局部最优等问题,提出一种改进约束鸡群算法ICCSO,改进了基本鸡群算法的边界约束处理机制,提高了算法的收敛速度和全局搜索能力。以标准测试函数和BP神经网络为例进行数值仿真,仿真结果表... 详细信息

针对基本鸡群优化算法CSO存在收敛速度慢、易陷入局部最优等问题,提出一种改进约束鸡群算法ICCSO,改进了基本鸡群算法的边界约束处理机制,提高了算法的收敛速度和全局搜索能力。以标准测试函数和BP神经网络为例进行数值仿真,仿真结果表明了所提出的改进约束鸡群优化算法的合理性及有效性。

关键词：鸡群算法 BP神经网络进化机制约束函数

孕中、晚期阴道超声测量宫颈长度对预测早产的临床价值

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生殖与避孕 2011年第6期31卷 426-429页

作者：张祎舒群上海市长宁区妇幼保健院上海200051

目的:研究孕中、晚期经阴道超声测量宫颈长度对预测早产的临床价值。方法:回顾性分析无任何严重合并症或并发症的单胎头位初产妇241例(A组),包括早产55例(A1组)、足月产186例(A2组),在孕中期14￣15+6周及23￣24+6周分别行阴道超声测量... 详细信息

目的:研究孕中、晚期经阴道超声测量宫颈长度对预测早产的临床价值。方法:回顾性分析无任何严重合并症或并发症的单胎头位初产妇241例(A组),包括早产55例(A1组)、足月产186例(A2组),在孕中期14￣15+6周及23￣24+6周分别行阴道超声测量宫颈长度;另选择同期住院的先兆早产孕妇63例(孕28￣34+6周)(B组)行阴道超声测量宫颈长度。所有对象均于初次产检时取阴道分泌物进行生殖道感染的筛查,分析宫颈长度变化、生殖道感染与早产的关系。结果:①A1组与A2组孕中期不同孕周的宫颈长度组间比较无显著差异(P>0.05),孕23￣24+6周的宫颈长度明显长于孕14￣15+6周的(P0.05),但1周后复测宫颈长度的21例中,12例早产者(C1组)宫颈长度的缩短明显大于足月产的9例(C2组),两者间比较有显著性差异(P<0.05)。②A1组的支原体感染率显著高于A2组(P<0.05);A1组合并2种或以上感染者高于B组,组间比较亦有显著性差异(P<0.05)。结论:阴道超声动态检测宫颈可预测早产,但孕中期超声测量宫颈长度对正常孕妇预测早产的意义不大;对先兆早产孕妇发生早产有一定的预测价值。对孕期出现生殖道感染的孕妇尤其是支原体感染或同时存在2种或以上感染者更应加以重视,预防早产。

关键词：孕中、晚期阴道超声宫颈长度生殖道感染早产预测

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私有化与公有化之间的博弈——重读《李顺大造屋》兼及对新时期农村题材小说的反思

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石河子大学学报（哲学社会科学版） 2013年第1期27卷 81-88页

作者：张书群石河子大学文学艺术学院新疆石河子832003

作为新时期农村小说的一个重要起点,《李顺大造屋》折射出私有化与公有化之间的博弈与纠葛。基于此,该文通过重读文本,重新认识其在当代文学史中的地位,并对中国当代近三十年来的农村历史做更深入的社会学考察,探究私有化与公有化之间... 详细信息

作为新时期农村小说的一个重要起点,《李顺大造屋》折射出私有化与公有化之间的博弈与纠葛。基于此,该文通过重读文本,重新认识其在当代文学史中的地位,并对中国当代近三十年来的农村历史做更深入的社会学考察,探究私有化与公有化之间的复杂纠葛,进而对以《李顺大造屋》为代表的新时期农村题材小说存在的合法性问题进行探讨与反思。

关键词：《李顺大造屋》新时期农村小说私有化公有化博弈

一种新的移动Ad Hoc网络随机密钥分发机制

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计算机工程与科学 2007年第5期29卷 8-10页

作者：崔国华张群书华中科技大学计算机科学与技术学院湖北武汉430074

移动Ad Hoc网络是一种无需固定通信基础设施、拓扑结构动态变化的无线网络,所以传统的密钥管理机制不能应用于Ad Hoc网络。本文在分析文献[1]中所提出的无线网络随机密钥分发机制的基础上提出了一个改进的基于环形通信的密钥分发协议,... 详细信息

移动Ad Hoc网络是一种无需固定通信基础设施、拓扑结构动态变化的无线网络,所以传统的密钥管理机制不能应用于Ad Hoc网络。本文在分析文献[1]中所提出的无线网络随机密钥分发机制的基础上提出了一个改进的基于环形通信的密钥分发协议,并对该协议进行了安全性和性能上的分析。在建立结点之间的安全信道时,该协议引入环状的合作结点集,不仅能够保证安全性和鲁棒性,而且大大降低了通信量。

关键词：移动自组网密钥管理密钥分发

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

MixerKT:A Knowledge Tracing Model Based on Pure MLP Architecture

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Computers, Materials & Continua 2025年第1期82卷 485-498页

作者： Jun Wang Mingjie Wang Zijie Li Ken Chen Jiatian Mei shu zhang Key Laboratory of Education Informatization for Nationalities Ministry of EducationYunnan Normal UniversityKunming650000China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming650000China

In the field of intelligent education,the integration of artificial intelligence,especially deep learning technologies,has garnered significant *** tracing(KT)plays a pivotal role in this field by predicting students’future performance through the analysis of historical interaction data,thereby assisting educators in evaluating knowledgemastery and tailoring instructional *** knowledge tracingmethods,largely based on Recurrent Neural Networks(RNNs)and Transformer models,primarily focus on capturing long-term interaction patterns in sequential ***,these models may neglect crucial short-term dynamics and other relevant *** paper introduces a novel approach to knowledge tracing by leveraging a pure Multilayer Perceptron(MLP)*** proposeMixerKT,a knowledge tracing model based on theHyperMixer framework,which uniquely integrates global and localMixer feature *** architecture enables more effective extraction of both long-terminteraction trends and recent learning behaviors,addressing limitations in currentmodels thatmay overlook these key *** evaluations on twowidely-used datasets,ASSIS Tments2009 and Algebra2005,demonstrate that MixerKT consistently outperforms several state-of-the-art models,including DKT,SAKT,and Separated Self-Attentive Neural Knowledge Tracing(SAINT).Specifically,MixerKT achieves higher prediction accuracy,highlighting its effectiveness in capturing the nuances of learners’knowledge *** results indicate that our model provides a more comprehensive representation of student learning patterns,enhancing the ability to predict future performance with greater precision.

关键词： Knowledge tracing multilayer perceptron channel mixer sequence mixer

根植故土情系家园——论黄春明小说中的地理书写与文学体验

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石河子大学学报（哲学社会科学版） 2008年第3期22卷 59-62页

作者：张书群石河子大学文学艺术学院新疆石河子832003

在台湾文坛,黄春明凭着对故乡的深爱,以饱蘸感情的笔触,把自己的童年经历、生命体验和对故乡的地理书写融为一体,形象地描绘出一幅美仑美奂的"宜兰乡土风貌图",既写出故乡的"常",又写出故乡的"变"。该文即从宜兰地理风貌与田园风光、时... 详细信息

在台湾文坛,黄春明凭着对故乡的深爱,以饱蘸感情的笔触,把自己的童年经历、生命体验和对故乡的地理书写融为一体,形象地描绘出一幅美仑美奂的"宜兰乡土风貌图",既写出故乡的"常",又写出故乡的"变"。该文即从宜兰地理风貌与田园风光、时代变迁的理性观照以及乡土语言的合理运用几个方面,对黄春明小说中凸显出的地域色彩与文学体验进行深入探讨和研究。

关键词：黄春明宜兰地理书写文学体验