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On Levine–O'Sullivan's Sequence and Its Conjecture

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Acta Mathematica Sinica,English Series 2016年第8期32卷 961-966页

作者： jia Yuan HU wen peng ZHANG School of Mathematics Northwest University

Let ql = 1, and qn be the largest value of （k ＋ 1）（n - qk） for all integers 1 ≤ k≤ n - 1 with n ≥ 2. The sequence Q -- {q1, q2, q3,...} is called Levine-O＇Sullivan sequence. In this paper, we use the combinational and analysis skill and the mathematical induction to study the asymptotic properties of qn, and give an interesting asymptotic formula for it. This solved a conjecture proposed by Professor Chen Yonggao.

关键词： Levine-O'Sullivan sequence sum-free sequences estimate conjecture

Lignin derived porous carbon with favorable mesoporous contributions for highly efficient ionic liquid-based supercapacitors

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Chinese Chemical Letters 2023年第10期34卷 293-297页

作者： jia Liu Xiu-wen Mei Feng peng Beijing Key Laboratory of Lignocellulosic Chemistry MOE Engineering Research Center of Forestry Biomass Materials and BioenergyBeijing Forestry UniversityBeijing 100083China

Lignin and its derivatives hold great potential in developing high performance porous carbon materials for supercapacitors due to the versatile features of high carbon content, abundant multifunctional groups,low cost, and environmental benefits. Unfortunately, their derived porous carbon generally has the features of unfavorable microporous-dominated morphologies and low specific surface area(SSA) attributed from the highly-branched structure of lignin, which are hardly suitable for the supercapacitors with ionic liquid(IL) electrolyte, leading to poor energy density and rate capability. Herein, porous carbon materials with desirable mesoporous contributions from sodium lignosulphonate are designed via a facile template method. Such rich mesoporisity carbon materials not only possess with three-dimensional interconnected network, large SSA, as well as favorable pore size distribution for accelerated ion and electron mass transfer, but also feature low heteroatom content for high electrochemical stability. Consequently, the optimal electrode exhibits a high capacitance of 166 F/g at 0.5 A/g, superior rate performance(59 Wh/kg at 59 kW/kg), as well as impressive cycle life with good capacitance retention of 93.1% in EMIBF4 electrolytes. The present work opens a new avenue to design porous carbon materials with high mesopore properties from lignin for effective compatibility with IL electrolyte in high-performance supercapacitors.

关键词： Lignin Porous carbon Favorable mesoporous contributions Low heteroatom content Supercapacitors

腹股沟疝无张力修补术后医院感染的病原菌分布特征与耐药性分析

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中华医院感染学杂志 2017年第5期27卷 1101-1104页

作者：高春玲刘晓慧朱文嘉彭二娟闫保功平顶山市第一人民医院普外三科河南平顶山467000

目的调查医院腹股沟疝无张力修补术后患者医院感染病原菌种类,分析病原菌的分布及耐药性,为临床该类手术感染的早期预防和术后治疗方案提供策略。方法收集2014年6月~2016年6月在医院行腹股沟疝无张力修补术患者800例,对术后感染患者采... 详细信息

目的调查医院腹股沟疝无张力修补术后患者医院感染病原菌种类,分析病原菌的分布及耐药性,为临床该类手术感染的早期预防和术后治疗方案提供策略。方法收集2014年6月~2016年6月在医院行腹股沟疝无张力修补术患者800例,对术后感染患者采集感染部位分泌物进行细菌培养和耐药性分析。结果 800例腹股沟疝无张力修补术患者共发生术后医院感染35例,感染率为4.38%,感染部位有切口感染、泌尿系统感染以及呼吸系统感染。35例医院感染患者脓液培养获得病原菌69株,革兰阳性菌43株,占62.32%,革兰阴性菌25株,占36.23%。金黄色葡萄球菌、肺炎链球菌、表皮葡萄球菌对青霉素和磺胺甲恶唑/甲氧苄啶耐药性高,铜绿假单胞菌对头孢他啶、亚胺培南和阿米卡星均有较高的敏感性,耐药率均较低;鲍曼不动杆菌对临床常用的抗菌药物均表现出高度的耐药性;肺炎克雷伯菌及大肠埃希菌对头孢他啶、亚胺培南、磺胺甲恶唑/甲氧苄啶以及氨苄西林均敏感,耐药率均较低。结论医院腹股沟疝无张力修补术后患者医院感染病原菌感染以革兰阳性菌等为主,病原菌对不同抗菌药物表现出不同耐药性,耐药情况有普遍加强的趋势,该类临床手术应在治疗前予以联合抗菌用药,术后有针对性的及时调整,预防术后医院感染的发生。

关键词：腹股沟疝无张力修补术术后感染病原菌耐药性

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基于隐性句逗号识别的汉语长句机器翻译

外语学刊 2025年第1期 39-46页

作者：冯文贺李熳佳张文娟广东外语外贸大学外国语言学及应用语言学研究中心语言工程与计算实验室广州510420 广州理工学院计算机科学与工程学院广州510420

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个... 详细信息

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个隐性句逗数据集,实现基于预训练模型的隐性句逗识别方法,其中性能最好的Hierarchical BERT作为后续应用模型。进而,实现基于隐性句逗识别的汉英机器翻译方法。在新闻和文学公开翻译测试语料上基于预训练机器翻译模型的实验表明,对于汉语长句的英译,本文方法相比基准翻译的BLEU值整体有所提高,而且在相对稳健机器翻译模型上,呈现为句子越长本文方法效果越明显。

关键词：机器翻译长句翻译隐性句逗号汉语长句逗号识别句内标点

A strategy to obtain a high-density and high-strength zirconia ceramic via ceramic injection molding by the modification of oleic acid

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 718-725页

作者： jia-xin wen Tian-bin Zhu Zhi-peng Xie wen-bin Cao Wei Liu School of Materials Science and Engineering University of Science and Technology Beijing Sate Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University School of Electromechanical Engineering Guangdong University of Technology

Despite its unique high efficiency and good environmental compatibility, the water-soluble binder system still encounters problems achieving a desired sintered part via ceramic injection molding because of the poor compatibility and the powder-binder segregation between ceramic powders and binders. The objective of this study was to obtain a sintered part with excellent properties by introducing a small quantity of oleic acid to the surface of zirconia powders before the mixing process. As opposed to many previous investigations that focused only on the rheological behavior and modification mechanism, the sintering behavior and densification process were systematically investigated in this study. With the modified powders, debound parts with a more homogeneous and smaller pore size distribution were fabricated. Also, a higher density and greater flexural strength were achieved in the sintered parts fabricated using the modified powders.

关键词： ceramic materials zirconia injection molding oleic acid sintering

The Generic Uniqueness and Well-Posedness of NashEquilibria for Stable Population Games

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Journal of the Operations Research Society of China 2021年第2期9卷 455-464页

作者： wen-Sheng jia Xiao-Ling Qiu Ding-Tao peng School of Mathematics and Statistics Guizhou UniversityGuiyang 550025China Key Laboratory of Games Decision Making and Control Systems Guiyang 550025China

This paper aims at studying a new kind of stable population games introduced by *** and *** in *** first construct a complete distance space M consisting of stable population games and show that most of stable population games have unique Nash equilibrium point that according to Baire’s category *** implies that every stable population game that possesses more than one Nash equilibrium can be approached arbitrarily by a sequence of the stable population game each of which has a unique Nash ***,we construct a bounded rationality function and deduce some results on the generic well-posedness implying Tikhonov well-posedness and Hadamard well-posedness for stable population games.

关键词： Stable population games Generic uniqueness Generic well-posedness Bounded rationality

Weakly- and Semi-Supervised Fast Region-Based CNN for Object Detection

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Journal of Computer Science & Technology 2019年第6期34卷 1269-1278页

作者： Xing-Gang Wang jia-Si Wang peng Tang wen-Yu Liu School of Electronic Information and Communications Huazhong University of Science and Technology Wuhan 430074China

Learning an effective object detector with little supervision is an essential but challenging problem in computer vision applications. In this paper, we consider the problem of learning a deep convolutional neural network (CNN) based object detector using weakly-supervised and semi-supervised information in the framework of fast region-based CNN (Fast R-CNN). The target is to obtain an object detector as accurate as the fully-supervised Fast R-CNN, but it requires less image annotation effort. To solve this problem, we use weakly-supervised training images (i.e., only the image-level annotation is given) and a few proportions of fully-supervised training images (i.e., the bounding box level annotation is given), that is a weakly-and semi-supervised (WASS) object detection setting. The proposed solution is termed as WASS R-CNN, in which there are two main components. At first, a weakly-supervised R-CNN is firstly trained;after that semi-supervised data are used for finetuning the weakly-supervised detector. We perform object detection experiments on the PASCAL VOC 2007 dataset. The proposed WASS R-CNN achieves more than 85% of a fully-supervised Fast R-CNN's performance (measured using mean average precision) with only 10%of fully-supervised annotations together with weak supervision for all training images. The results show that the proposed learning framework can significantly reduce the labeling efforts for obtaining reliable object detectors.

关键词： object detection weakly-supervised learning semi-supervised learning fast region-based convolutional neural network (Fast R-CNN)

Covalent organic frameworks derived hollow structured N-doped noble carbon for asymmetric-electrolyte Zn-air battery

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Science China Chemistry 2019年第3期62卷 385-392页

作者： Pingwei Cai Xinxin peng Junheng Huang Jingchun jia Xiang Hu Zhenhai wen CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Science

We report a relatively low-temperature molten salt strategy to prepare hollow structured N-doped noble carbon(h-NNC) with highly desirable features of ultra-large surface area(1957 m^2 g^(-1)) and high graphitization, endowing the h-NNC with high activity toward catalysis of oxygen reduction reaction in acidic medium. The h-NNC is applied as cathode catalyst of an asymmetrical-electrolyte Zn-air battery, which exhibits an open circuit voltage of 2.11 V, a power density up to 270 mW cm^(-2),and an energy density of 1279 W h kg^(-1), behaving advantages over the conventional Zn-air batteries.

关键词： noble carbon oxygen reduction reaction asymmetric-electrolyte Zn-air battery energy density

Optimizing luminescence sensitivity and moisture stability of porous coordination frameworks by varying ligand side groups

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Science China Chemistry 2019年第3期62卷 341-346页

作者： jia-wen Ye Xu-Yu Li Hao-Long Zhou Jie-peng Zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry Sun Yat-Sen University

Hydrophobic ethyl, butyl or hexyl groups were introduced into the dicarboxylate ligand in the fluorescent porous coordination framework [Zn_2(fda)_2(bpy)](LMOF-202, H_2fda=9H-fluorene-2,7-dicarboxylic acid, bpy=4,4′-bipyridine) for improving water stability and tuning oxygen sensitivity. The long hexyl groups gave satisfactory water stability but its oxygen sensitivity is low(70.8% fluorescence quenched at 1 bar O_2(1 bar=105 Pa)). In contrast, the shorter side groups gave high oxygen sensitivity(93.9% fluorescence quenched at 1 bar O_2) and low water stability. The derivation of the Stern-Volmer curves of the O_2 luminescence quenching data from the linear form can be used for detecting trace impurities in the luminescent framework, being much more sensitive than conventional methods such as powder X-ray diffraction. Mixing the ethyl and hexyl groups in the solid-solution manner brought high oxygen sensitivity(96.4% fluorescence quenched at 1 bar O_2) and high water stability simultaneously in the same coordination framework.

关键词： metal-organic framework water stability oxygen fluorescence sensor