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Arbitrary-Order Fractance Approximation Circuits With High Order-Stability Characteristic and Wider Approximation Frequency Bandwidth

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1425-1436页

作者： Qiu-yan He Yi-Fei Pu bo Yu xiao Yuan College of Computer Science Sichuan UniversityChengdu 610065China College of Physics and Engineering Chengdu Normal UniversityChengdu 611130China College of Electronics and Information Engineering Sichuan UniversityChengdu 610065China

This paper discusses a novel rational approximation algorithm of arbitrary-order fractances,which has high orderstability characteristic and wider approximation frequency *** fractor has been exploited extensively in various scientific *** well-known shortcoming of the existing fractance approximation circuits,such as the oscillation phenomena,is still in great need of special research *** by this need,a novel algorithm with high orderstability characteristic and wider approximation frequency bandwidth is *** order to better understand the iterating process,the approximation principle of this algorithm is investigated at ***,features of the iterating function and frequency-domain characteristics of the impedance function calculated by this algorithm are researched,***,approximation performance comparisons have been made between the corresponding circuit and other types of fractance approximation ***,a fractance approximation circuit with the impedance function of negative2/3-order is *** high order-stability characteristic and wider approximation frequency bandwidth are fundamental important advantages,which make our proposed algorithm competitive in practical applications.

关键词： Fractal fractance fractional calculus fractional-order systems

基于网络药理学探讨口腔愈疡冲剂治疗口腔扁平苔藓分子作用机制

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江西中医药大学学报 2023年第1期35卷 78-81,85页

作者：王宗康肖艳波朱可可谭劲湖南中医药大学第一附属医院长沙410007

目的:探究中药复方口腔愈疡冲剂治疗口腔扁平苔藓(OLP)的作用机制,为进一步实验验证提供理论基础。方法:基于网络药理学方法,使用中药系统药理学数据库与分析平台(TCMSP)等多个数据库筛选口腔愈疡冲剂的有效成分和对应靶点;在OMIM和Gene... 详细信息

目的:探究中药复方口腔愈疡冲剂治疗口腔扁平苔藓(OLP)的作用机制,为进一步实验验证提供理论基础。方法:基于网络药理学方法,使用中药系统药理学数据库与分析平台(TCMSP)等多个数据库筛选口腔愈疡冲剂的有效成分和对应靶点;在OMIM和Gene Cards数据库筛选与口腔扁平苔藓相关的基因。通过Cytoscope 3.8.2和R软件构建网络图以及生物信息学分析。结果:筛选出口腔愈疡冲剂有效成分159个,口腔愈疡冲剂治疗OLP的作用靶点59个;山奈酚(kaempferol)、槲皮素(quercetin)、丹参酮(Tanshinone)、黄芩素(baicaleim)、鞣花酸(ellagic acid)、木犀草素(luteolin)、β-谷甾醇(beta-sitosterol)可能是口腔愈疡冲剂治疗OLP的主要活性成分。其作用于IL6、VEGFA、AKT1、EGF等靶点,参与细胞因子受体结合、信号受体激活剂活性、细胞因子活性等生物过程,通过Toll样受体信号通路、TNF信号通路、JAK-STAT信号通路、PI3K-Akt信号通路、Th17细胞分化信号通路等共同发挥治疗OLP的作用。结论:口腔愈疡冲剂可以通过多成分、多靶点、多渠道、协同作用于OLP,揭示了其治疗OLP的潜在有效成分和作用机制,为后续的研究提供了理论依据。

关键词：口腔愈疡冲剂口腔扁平苔藓网络药理学靶点通路

Epigenetics in the modern era of crop improvements

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Science China Life Sciences 2025年

作者： yan Xue xiaofeng Cao Xiangsong Chen Xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan xiaofeng Fang Lei Gong Zhizhong Gong xiaofeng Gu Chongsheng He Hang He Shengbo He Xinjian He yan He Yuehui He Guifang Jia Danhua Jiang Jianjun Jiang Jinsheng Lai Zhaobo Lang Chenlong Li Qing Li Xingwang Li Bao Liu Bing Liu xiao Luo Yijun Qi Weiqiang Qian Guodong Ren Qingxin Song Xianwei Song Zhixi Tian Jiawei Wang Yuan Wang Liang Wu Zhe Wu Rui Xia Jun xiao Lin Xu Zhengyi Xu Wenhao yan Hongchun yang Jixian Zhai Yijing Zhang Yusheng Zhao Xuehua Zhong Daoxiu Zhou Ming Zhou Yue Zhou bo Zhu Jiankang Zhu Qikun Liu College of Life Sciences Institute of Life Science and Green Development Hebei University Biotechnology Research Institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University Institute of Advanced Agricultural Sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National Institute of Biological Sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural Sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers Science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya Institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory Institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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A Survey on Deep Learning-based Fine-grained Object Classification and Semantic Segmentation

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International Journal of Automation and computing 2017年第2期14卷 119-135页

作者： bo Zhao Jiashi Feng xiao Wu Shuicheng yan School of Information Science and Technology Southwest Jiaotong University Department of Electrical and Computer Engineering National University of Singapore

The deep learning technology has shown impressive performance in various vision tasks such as image classification, object detection and semantic segmentation. In particular, recent advances of deep learning techniques bring encouraging performance to fine-grained image classification which aims to distinguish subordinate-level categories, such as bird species or dog breeds. This task is extremely challenging due to high intra-class and low inter-class variance. In this paper, we review four types of deep learning based fine-grained image classification approaches, including the general convolutional neural networks （CNNs）, part detection based, ensemble of networks based and visual attention based fine-grained image classification approaches. Besides, the deep learning based semantic segmentation approaches are also covered in this paper. The region proposal based and fully convolutional networks based approaches for semantic segmentation are introduced respectively.

关键词： Deep learning fine-grained image classification semantic segmentation convolutional neural network (CNN) recurrentneural network (RNN)

Rigid Biphenyl-contained Epoxy Resins with Improved Thermal Resistant Properties

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Chinese Journal of Polymer Science 2017年第11期35卷 1428-1435页

作者： xiao-yan Wei bo-xuan Zhao 尚亚卓程元荣 Key Laboratory for Advanced Materials School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai Wujing Optoelectronics Sci&Tech Co. Ltd Department of Materials Science Fudan University

Biphenyl-contained monomer of 1,4-bis[2-（3,4-epoxy cyclohexyl ethyl） dimethylsilyl] biphenyl （BP-SiH-EP） was prepared via hydrosilylation reaction of 1,4-bis（dimethylsilyl） biphenyl （BP-SiH） and 1,2-epoxy-4-vinylcyclohexane in the presence of Karstedt＇s catalyst. ^1H-NMR, 13C-NMR and FTIR were used to characterize the structure of the obtained monomer. BP-SiH-EP was then cured by methyl hexahydrophthalic anhydride （MeHHPA） with 1-cyanoethyl-2-ethyl-4- methylimidazole as an accelerator. The polymerization behavior was studied by DSC. The results of DMA measurement demonstrate that the cured BP-SiH-EP/MeHHPA can maintain high storage modulus （〉1 GPa） in a wide range of temperature up to 176 ℃. According to the damping factor curve of DMA, cured BP-SiH-EP/MeHHPA exhibits a high glass transition temperature （Tg） of 192 ℃, which is 20 ℃ higher than that of cured 1,4-bis[2-（3,4-epoxy cyclohexyl ethyl） dimethylsilyl] benzene （DEDSB）/MeHHPA. TGA results show that cured BP-SiH-EP/MeHHPA has good thermal stability （Tso/o = 339 ℃） due to the high heat-resistance of rigid biphenyl group. Moreover, the crosslinking density of cured BP-SiH-EP/MeHHPA should be lower than that of cured DEDSB/MeHHPA estimated from their chemical structures, which conflicts with the calculated results based on the rubber elasticity equation. The inconsistence indicates that the calculated crosslinking densities are not comparable, possibly owing to their differences in the rigidity of polymer chains and intermolecular interaction.

关键词： Epoxy resin Hydrosilylation Biphenyl group Thermal property Crosslinking density

基于数据挖掘技术的中医学隐性知识显性化分析

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中国实验方剂学杂志 2017年第10期23卷 221-226页

作者：范铁兵宁秋萍杨志旭顾东黎朱晓博燕嫱中国中医科学院北京100700 中国中医科学院西苑医院北京100091 中国农业大学北京100083

隐性知识是知识的核心,中医学隐性知识是中医学的重要组成部分。中医学隐性知识显性化是实现中医学知识有效交流与共享的必要条件,是促进中医学发展与创新的重要保障,但中医学隐性知识显性化过程会受诸多因素的影响。数据挖掘技术能够... 详细信息

隐性知识是知识的核心,中医学隐性知识是中医学的重要组成部分。中医学隐性知识显性化是实现中医学知识有效交流与共享的必要条件,是促进中医学发展与创新的重要保障,但中医学隐性知识显性化过程会受诸多因素的影响。数据挖掘技术能够从大量的、不完全的、模糊的、随机的实际应用数据中,提取隐含在其中的、事先未知的、潜在的、有用的信息和知识。基于数据挖掘技术提取隐性知识的优势,本文围绕关联规则分析、复杂系统熵聚类分析、决策树分析、因子分析、贝叶斯网络分析等数据挖掘技术支持下的中医学隐性知识显性化进行了研究。通过文献分析与整理,以具体数据挖掘技术为分类标准和主线,研究对象涉及单个医家、古代医学典籍及现代临床研究等,研究内容涉及中医病因病机、治则治法、辨证规律、方剂使用规律、药对组方规律及其相关性等多个层面的中医学隐性知识。结果表明,针对研究内容的特点,选取针对性的数据挖掘技术能够实现中医学隐性知识的显性化,这有利于拓展中医学隐性知识显性化的渠道,有利于提高中医学隐性知识显性化的程度,有利于最大限度的实现中医学隐性知识显性化与共享。基于数据挖掘技术在中医学隐性知识显性化过程中的积极作用,具有中医特色的数据挖掘传承平台应加以推广、整合与优化,促进中医学的传承与创新。

关键词：数据挖掘隐性知识显性化研究综述

Correlation Between Microstructure and Mechanical Properties of 2219-T8 Aluminum Alloy Joints by VPTIG Welding

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 438-446页

作者： Lan-Qiang Niu xiao-yan Li Liang Zhang xiao-bo Liang Mian Li College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

In this study, 2219-T87 aluminum alloys were butt welded by the double-pass tungsten inert gas arc welding process. And the softening behavior of fusion zone（FZ） and heat-affected zone（HAZ） was evaluated with the analysis of welding temperature field, grain size, alloying element distribution and precipitates evolution. Results show that the two FZs are almost the weakest regions in the joint, where the microhardness value is 76 and 78 HV, respectively. Microhardness of the HAZ generally grows along with increasing distance from fusion line except a valley value at the distance of about 4.5 mm. The mean grain size of two FZs is about 74.4 and 79.2 lm, whereas 41.5, 44.9 and 43.4 lm for the two measured HAZs and base metal（BM）, respectively. There is about 60.4% and 54.2% Cu consumed in the coarse whitish particles of FZs that have little strengthening effect, while the percentage is about 24.6% of BM that is almost the same as HAZ. A large number of strengthening phases h0 distribute dispersively in BM, whereas hardly any precipitates exist in FZ and HAZ adjacent to FZ. So the coarsening of grain size, reduction and segregation of alloying element content, and the precipitate evolution are regarded as the main causes of softening in FZ, while the precipitate evolution is the main factor of softening in HAZ.

关键词： 2219-T87 Aluminum alloy TIG welding Fusion zone Heat-affected zone Softening behavior

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发酵过程中溶氧浓度对D-核糖发酵的影响

微生物学通报 2004年第3期31卷 21-25页

作者：于志萍王昌禄顾晓波杨志岩天津科技大学食品科学与生物工程学院天津300222

通过固定不同溶氧浓度(DOT)对短小芽孢杆菌(Bacillus pumlus)进行分批发酵的过程参数变化的比较,发现发酵前期与后期对氧的需求不尽相同,探讨了氧代谢途径及溶氧浓度对核糖发酵的影响机理,并提出分阶段供氧模式。结果表明,发酵时间44h后... 详细信息

通过固定不同溶氧浓度(DOT)对短小芽孢杆菌(Bacillus pumlus)进行分批发酵的过程参数变化的比较,发现发酵前期与后期对氧的需求不尽相同,探讨了氧代谢途径及溶氧浓度对核糖发酵的影响机理,并提出分阶段供氧模式。结果表明,发酵时间44h后,整个发酵过程保持了较高的核糖产率和葡萄糖消耗率,最终核糖产量和细胞生成量分别提高了5.0％和18.8％。

关键词：溶氧浓度 D-核糖短小芽孢杆菌

Numerical evaluation of the effect of fracture network connectivity in naturally fractured shale based on FSD model

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Science China Earth Sciences 2016年第3期59卷 626-639页

作者： WANG Yu LI xiao ZHOU Run Qing ZHENG bo ZHANG bo WU yan Fang Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China

In this paper, the effect of pre-existing discrete fracture network(DFN) connectivity on hydraulic fracturing is numerically investigated in a rock mass subjected to in-situ stress. The simulation results show that DFN connectivity has a significant influence on the hydraulic fracture(HF) & DFN interaction and hydraulic fracturing effectiveness, which can be characterized by the total interaction area, stimulated DFN length, stimulated HF length, leak-off ratio, and stimulated total length. In addition, even at the same fluid injection rate, simulation models exhibit different responses that are strongly affected by the DFN connectivity. At a low injection rate, total interaction area decreases with increasing DFN connectivity; at a high injection rate, total interaction area increases with the increase of DFN connectivity. However, for any injection rate, the stimulated DFN length increases and stimulated HF length decreases with the increase of connectivity. Generally, this work shows that the DFN connectivity plays a crucial role in the interaction between hydraulic fractures, the pre-existing natural fractures and hydraulic fracturing effectiveness; in return, these three factors affect treating pressure, created microseismicity and corresponding stimulated volume. This work strongly relates to the production technology and the evaluation of hydraulic fracturing effectiveness. It is helpful for the optimization of hydraulic fracturing simulations in naturally fractured formations.

关键词： Hydraulic fracturing DFN Fracture network connectivity Numerical simulation