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贝叶斯程序分析

电子学报 2024年第4期52卷 1155-1172页

作者：张昕王冠成吴宜谦陈逸凡李天驰张羿凡熊英飞高可信软件技术教育部重点实验室(北京大学) 北京100871 北京大学计算机学院北京100871

程序分析在软件开发和维护中发挥着关键作用.然而,传统基于逻辑的程序分析方法在处理现代复杂、大规模和动态特性丰富的软件系统时往往效果有限,其根源在于软件系统中的不确定性.研究人员针对具体的程序分析问题提出了一系列新的技术,... 详细信息

程序分析在软件开发和维护中发挥着关键作用.然而,传统基于逻辑的程序分析方法在处理现代复杂、大规模和动态特性丰富的软件系统时往往效果有限,其根源在于软件系统中的不确定性.研究人员针对具体的程序分析问题提出了一系列新的技术,其特征是在传统逻辑分析的基础上结合概率信息来捕获软件系统中的不确定性.通过总结和抽象这些已有工作,本文提出了贝叶斯程序分析框架,其核心思想是结合程序分析和贝叶斯统计推断,通过建模和更新关于程序的概率分布来推断有关程序行为的信息.贝叶斯程序分析采用概率逻辑编程来同时处理概率信息和逻辑信息,用统一的方式捕获了现有的多项不同工作,也能泛化到程序缺陷定位和差异调试等非传统程序静态分析任务上.本文给出了贝叶斯程序分析框架的定义,展示了该框架在程序分析和相关领域的应用,并展望了未来发展方向.

关键词：程序分析逻辑编程概率逻辑编程贝叶斯网络贝叶斯推断

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利用振动幅值进行滚动轴承外滚道故障定位

机械设计与制造 2024年第3期 40-42,47页

作者：高淑芝任玉龙李天池张义民沈阳化工大学装备可靠性研究所辽宁沈阳110142 沈阳化工大学信息工程学院辽宁沈阳110142

滚动轴承在机械传动中占有十分重要的地位,其运行状况直接影响着机械的运行效率。因此,对滚动轴承故障的研究具有十分重要的理论意义和现实意义。该文章在故障诊断的基础上提出一种故障定位的新方法。该方法利用三个振动传感器采集滚动... 详细信息

滚动轴承在机械传动中占有十分重要的地位,其运行状况直接影响着机械的运行效率。因此,对滚动轴承故障的研究具有十分重要的理论意义和现实意义。该文章在故障诊断的基础上提出一种故障定位的新方法。该方法利用三个振动传感器采集滚动轴承运行过程中的振动信号,然后利用相关分析法与EMD算法对其进行去干扰处理,提取振动信号的幅值,并计算其衰减量。利用三个传感器采集到的三处振动信号衰减量来分析计算故障的准确位置。该方法简单,提取特征值少,定位精度高。且该方法不仅能准确定位滚动轴承外滚道单点故障,而且可同时定位出多个故障点。这在以往的定位方法中是很难实现的。

关键词：相关分析法 EMD 三角定位法故障定位

Investigation of the possible source for the solar energetic particle event on 2017 September 10

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Research in Astronomy and Astrophysics 2018年第7期18卷 1-10页

作者： Ming-Xian Zhao Gui-Ming Le Yu-tian chi Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China School of Computer Science Anhui University of TechnologyMa'anshan 243032China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

According to the solar proton data observed by Geostationary Operational Environmental Satellites （GOES）, ground-based neutron monitors on Earth and near-relativistic electron data measured by the ACE spacecraft, the onset times of protons with different energies and near-relativistic electrons have been estimated and compared with the time of solar soft and hard X-ray and radio burst data. The results show that first arriving relativistic and non-relativistic protons and electrons may have been accelerated by the concurrent flare. The results also suggest that release times of protons with different energies may be different, and the protons with lower energy may have been released earlier than those with higher energy. Some protons accelerated by concurrent flares may be further accelerated by the shock driven by the associated CME.

关键词： Sun coronal mass ejections (CMEs) - Sun flares - Sun particle emission

Review of Methods of Image Segmentation Based on Quantum Mechanics

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Journal of Electronic Science and Technology 2018年第3期16卷 241-250页

作者： tian-chi Zhang Jing Zhang Jian-Pei Zhang He Wang the College of Computer Science and Technology Harbin Engineering UniversityHarbin 150001 the Department of Computer Science and Technology Institute of TechnologyShantou UniversityShantou 515063 the School of Information Science and Engineering University of JinanJinan 250022

The quantum theory application is a hot research area in recent years, especially the theory of quantum mechanics. In this paper, we focus on the research of image segmentation based on quantum mechanics. Firstly,the theory of quantum mechanics is introduced; afterwards, a review of image segmentation methods based on quantum mechanics is presented; and finally, the characteristics about the quantum mechanics applied to image processing are concluded. Two main research topics are discussed in this paper. One is to emphasize that quantum mechanics can be applied in different research areas, such as image segmentation, and the second is to conclude some methods in image segmentation and give some suggestions for possible novel methods by applying quantum mechanics theory. As a summary, this is a review paper which presents some methods based on the feasible theory in quantum mechanics aiming at achieving a better performance in image segmentation.

关键词： Image segmentation quantum entangle quantum mechanics

Excellent Compatibilization Effect of a Dual Reactive Compatibilizer on the Immiscible MVQ/PP Blends

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chinese Journal of Polymer Science 2023年第7期41卷 1133-1141页

作者： Han-Bin Wang Hong-chi tian Shi-Jia Zhang Bing Yu Nan-Ying Ning Ming tian Li-Qun Zhang Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials Beijing University of Chemical TechnologyBeijing100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing100029China Shandong Dawn Polymer Material Co. Ltd.Longkou265700China

Methyl vinyl silicone rubber (MVQ)/polypropylene (PP) thermoplastic vulcanizate (TPV) combines the good melt processability, recyclability and sealing performance as well as biosafety, stain and fluid resistance, and thus it is especially suitable in bio-safety areas and wearable electronic devices, etc. Nevertheless, the compatibility between MVQ and PP phases is poor. A big challenge on the compatibilization of MVQ/PP blends is that neither MVQ nor PP contains any reactive groups. In this study, a dual reactive compatibilizer composed of ethylenemethyl acrylate-glycidyl methacrylate terpolymer (EMA-co-GMA) and maleic anhydride grafted polypropylene (PP-g-MAH) was designed for the compatibilization of MVQ/PP blends. During melt blending, a copolymer compatibilizer at the MVQ/PP interface can be formed because of the in situ reaction between EMA-co-GMA and PP-g-MAH. The thermodynamic predict of its compatibilization effect through calculating the spreading coefficient of the in situ formed copolymer indicates that it can well compatibilize MVQ/PP blends. The experimental results show that under the GMA/MAH molar ratio of 0.5/1, the interface thickness largely increase from 102 nm for non-compatibilized blend to 406 nm, and the average size of MVQ dispersed phase largely decreases from 2.3 µm to 0.36 µm, the Tg of the two phases shifts toward each other, the mixing torque and mechanical properties of the blend are increased, all indicating its good compatibilization effect. This study provides a good compatibilizing method for immiscible MVQ/PP blends with no reactive groups in both components for the preparation of high performance MVQ/PP TPVs.

关键词： Methyl vinyl silicone rubber(MVQ) Polypropylene(PP) Immiscible polymer blends Reactive compatibilization

Site-directed RNA editing(SDRE):Off-target effects and their countermeasures

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Journal of Genetics and Genomics 2019年第11期46卷 531-535页

作者： Shaoshuai Mao Yajing Liu Shisheng Huang Xingxu Huang tian chi School of Life Sciences and Technology ShanghaiTech UniversityShanghai201210China CAS Center for Excellence in Molecular Cell Science Shanghai Institute of Biochemistry and Cell BiologyChinese Academy of SciencesShanghai200031China University of chinese Academy of Sciences Beijing100049China Department of Immunobiology Yale University School of MedicineNew HavenCT 06520USA

Site-directed RNA editing(SDRE)is invaluable to basic research and clinical applications and has emerged as a new frontier in genome *** past few years have witnessed a surge of interest in SDRE,with SDRE tools emerging at a breathtaking ***,off-target effects of SDRE remain a tough problem,which constitutes a major hurdle to their clinical *** we discuss the diverse strategies for combating off-target editing,drawing lessons from the published studies as well as our ongoing ***,SDRE is still at its infancy,with significant challenges and exciting opportunities ahead.

关键词： Gene editing RNA editing Cas13 Off-target Specificity

Magnetization reversal behavior and first-order reversal curve diagrams in high-coercivity Zr-doped α-Fe/Nd_(2)Fe_(14)B nanocomposite alloys

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Rare Metals 2021年第5期40卷 1232-1238页

作者： tian-chi Ji Min-Xiang Pan Hong-Liang Ge Qiong Wu Peng-Yue Zhang Magnetism Key Laboratory of Zhejiang Province China Jiliang UniversityHangzhou 310018China

In the present work,the magnetization reversal behavior for the melt spinning(Nd_(0.8)Ce_(0.2))_(2)Fe_(12)Co_(2-x)Zr_(x)B(x=0,0.5)permanent alloys with high coercivity was investigated by analyzing the hysteresis curves and the recoil *** to the Zr-free alloy,the Zr-doped sample obtains higher magnetic properties:coercivity of H_(cj)=650.5 kA·m^(-1),squareness of H_(k)/H_(cj)=0.76 and maximum energy product of(BH)_(max)=131.0 kJ·m^(-3).The first-order reversal curves(FORCs)analysis was taken to identify optimal conditions of exchange coupling for the Zr-free and Zr-doped *** coercivity mechanism of theα-Fe/Nd_(2)Fe_(14)B nanocomposite alloys was analyzed by the angular dependence of the coercive field as measured for the Zr-doped *** results show that the magnetic reverse process of the Zr-doped sample can be explained by the pinning model.

关键词： Magnetization reversal Coercivity mechanism First-order reversal curve(FORC) Nanocomposite

葡萄CYP707A基因家族的鉴定及对果实成熟的功能验证

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生物技术通报 2024年第2期40卷 160-171页

作者：龚丽丽余花杨杰陈天池赵双滢吴月燕上海海洋大学水产与生命学院上海200120 浙江万里学院宁波315100

【目的】CYP707A是细胞色素P450家族的亚家族成员,所编码的ABA8'-羟化酶是ABA分解代谢的关键酶,对植物生长发育起着重要作用。鉴定葡萄CYP707A基因家族,可为进一步研究葡萄果实成熟机理和生物育种技术提供理论依据。【方法】利用生物学... 详细信息

【目的】CYP707A是细胞色素P450家族的亚家族成员,所编码的ABA8'-羟化酶是ABA分解代谢的关键酶,对植物生长发育起着重要作用。鉴定葡萄CYP707A基因家族,可为进一步研究葡萄果实成熟机理和生物育种技术提供理论依据。【方法】利用生物学信息方法分析葡萄中CYP707A家族基因的基因结构、蛋白基序、染色体定位、共线性、系统进化关系及启动子区顺式作用元件等,并利用RT-q PCR分析VvCYP707A基因在葡萄不同品种(早熟和中熟)的时空表达模式、组织表达模式以及对外源ABA处理的响应模式,并利用果实瞬时表达技术对Vitvi07g01751进行功能验证。【结果】葡萄基因组鉴定出5个VvCYP707As基因,分布于5条染色体,其中Vitvi02g01269、Vitvi07g01751和Vitvi18g00792为片段复制基因。CYP707A基因家族高度保守,其中,基因结构和蛋白基序相似,亚细胞定位均位于内质网;VvCYP707A启动子区域富含与生长发育和激素响应相关的顺式作用元件,均含有ABA激素响应元件;通过RT-qPCR检测基因的表达模式发现,VvCYP707A基因具有时空特异性和组织特异性,主要在果实的幼果期与膨大期和茎、叶组织中高表达,其中Vitvi07g01751基因在早熟品种‘甬早红’膨大期果实中特异性高表达,且在两个品种间的表达模式一致,随着果实的成熟其表达先升高后降低。外源ABA处理下VvCYP707A分为两种表达模式,在浆果肉中外源ABA可诱导5个VvCYP707A基因高表达,在浆果皮中会显著抑制VvCYP707A基因的表达;在葡萄果实中瞬时表达Vitvi07g01751,葡萄的糖度积累缓慢,显著增加编码ABA的受体VvPYL4基因表达量,推测了Vitvi07g01751介导ABA调控葡萄果实成熟的机制。【结论】研究结果揭示了葡萄Vitvi07g01751在果实成熟中起着重要作用。

关键词：葡萄 CYP707A基因全基因组鉴定生物信息学果实成熟脱落酸 PYL基因

Comparative lipidomic analysis of S. cerevisiae cells during industrial bioethanol fermentation

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Frontiers of Chemical Science and Engineering 2012年第4期6卷 461-469页

作者： Bin QIAO Hong-chi tian Ying-Jin YUAN Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Variations in the composition and level of phospholipids （PLs） in yeast cells during industrial ethanol fermentation processes were analyzed. A comparative lipidomic method was used to investigate the changes in total cellular PLs during continuous and fed-batch/batch processes. The phospholipid metabolism in yeast changed during both processes, mainly due to the presence of longchain poly unsaturated fatty acids （PUFA） that contained phosphatidyglycerol （PG）, phosphatidylethanolamine （PE） and phosphatidylserine （PS）. The complexity of the media affected the growth of the yeast and the membrane composition. Yeast incorporated lots of exogenous saturated and PUFAs from the feedstock during the fermentations. During the continuous fermentation, there was an increase in PLs with shorter chains as the fermentation progressed and early in process there were more longchains. During the fed-batch/batch process, the PG species increased as the fermentation progressed. This is probably due to an inositol deficiency in the earlier part of the fermentation.

关键词： lipidomics systems biology phospholipids,stirred-tank saccharomyces cerevisiae biorefinery engi-neering