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Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

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Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui Su shu-fang Gong Qi-Zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

Submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) *** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization Cardinality constraint

Design and Implementation of Nonlinear Precoding for MIMO-SDMA Toward 6G Wireless

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China Communications 2024年第1期21卷 69-87页

作者： Chaowu Wu Yue Xiao shu fang Gang Wu National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we present a novel and robust nonlinear precoding(NLP)design and detection structure specifically tailored for multiple-input multipleoutput space division multiple access(MIMO-SDMA)systems toward 6G *** approach aims to effectively mitigate the impact of imperfect channel estimation by leveraging the channel fluctuation mean square error(MSE)for reconstructing a highly accurate precoding matrix at the ***,we introduce a simplified receiver structure that eliminates the need for equalization,resulting in reduced interference and notable enhancements in overall system *** conduct both computer simulations and experimental tests to validate the efficacy of our proposed *** results reveals that the proposed NLP scheme offers significant performance improvements,making it particularly well-suited for the forthcoming 6G wireless.

关键词： MIMO-SDMA nonlinear precoding Tomlinson-Harashima precoding(THP) vector perturbation(VP)

Photon counting technique as a potential tool in micro-defect detection of epoxy insulation pull rod in gas-insulated switchgears

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High Voltage 2024年第2期9卷 267-274页

作者： Xianhao Fan shu Niu Hanhua Luo Jizhong Liang fang Liu Wenqiang Li Weidong Liu Wensheng Gao Yulong Huang Chuanyang Li Jinliang he School of Electrical Engineering Tsinghua UniversityBeijingChina Electric Power Research Institute Shangxi Power Grid CorporationTaiyuanShanxiChina Shandong Taikai Electrical Insulation Co. Ltd.TaianShandongChina

The micro-defects in epoxy-based insulation materials generate a local high electric field which results in continuous degradation,seriously endangering the insulation system of gas-insulated switchgears.A highly sensitive detection technique is reported for micro-defects of insulation pull rods based on the photon counting(PC)*** re-sults demonstrated that for an epoxy-based insulation pull rod,the photons released during electroluminescence and ionisation at 2 kV,which is less than the partial discharge inception voltage,can be clearly *** findings presented a strong correlation between photon counts and defect *** has been conducted to elucidate the mechanism behind defect-induced PC,employing the amplification of ionising luminescence through electric field distortion induced by micro defects and the augmentation of electroluminescence through the aggregation of trap *** this regard,the authors verified that PC can serve as a potential tool in the detection of micro-insulation defects,which also has huge potential in online insulation condition monitoring.

关键词： technique. insulation defect

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光反馈双路自动控制声光调Q驱动器

光电子．激光 2008年第3期19卷 300-303页

作者：梁喆霍玉晶何淑芳清华大学电子工程系北京100084

提出了新型的光反馈双路自动控制声光调Q驱动器方案。它能够同步控制声光Q开关和LD抽运源的运转,实现根据测出的上一次Q开关打开至光脉冲产生间隔自动控制下一次调Q持续时间的功能,并具有10W以上的功率输出和15 ns(1个射频驱动振荡周期... 详细信息

提出了新型的光反馈双路自动控制声光调Q驱动器方案。它能够同步控制声光Q开关和LD抽运源的运转,实现根据测出的上一次Q开关打开至光脉冲产生间隔自动控制下一次调Q持续时间的功能,并具有10W以上的功率输出和15 ns(1个射频驱动振荡周期)内的声光Q开关响应时间的优良性能。可以在保持光脉冲性能、节省能源、高热稳定性的前提下,提升声光调Q全固态激光器在各种环境下的稳定性和易调节性。

关键词：声光调Q 全固态激光器光反馈自动控制双控驱动器

RNA viromes of Dermacentor nuttalli ticks reveal a novel uukuvirus in Qinghai Province,China

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Virologica Sinica 2024年第4期39卷 537-545页

作者： Yaohui fang Jun Wang Jianqing Sun Zhengyuan Su Shengyao Chen Jian Xiao Jun Ni Zhihong Hu Yubang he shu Shen Fei Deng Key Laboratory of Special Pathogens and Biosafety and National Virus Resource Center Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 101408China Qinghai Lake National Nature Reserve Administration Xining 810000China Hubei Jiangxia Laboratory Wuhan 430200China Xinjiang Key Laboratory of Vector-borne Infectious Diseases Urumqi830002China

Ticks are a major parasite on the Qınghai-Tibet Plateau,western China,and represent an economic burden to agriculture and animal *** research on tick-borne pathogens that threaten humans and animals,the viromes of dominant tick species in this area remain *** this study,we collected Dermacentor nuttalli ticks near Qınghai Lake and identified 13 viruses belonging to at least six families through metagenomic *** viruses were of high abundance in pools,including Xınjiang tick-associated virus 1(XJTAV1),and three novel viruses:Qınghai Lake virus 1,Qınghai Lake virus 2(QHLV1,and QHLV2,unclassified),and Qınghai Lake virus 3(QHLV3,genus Uukuvirus of family Phenuiviridae in order Bunyavirales),which lacks the M *** minimum infection rates of the four viruses in the tick groups were 8.2%,49.5%,6.2%,and 24.7%,respectively,suggesting the prevalence of these viruses in *** ticks.A putative M segment of QHLV3 was identified from the next-generation sequencing data and further characterized for its signal peptide cleavage site,N-glycosylation,and transmembrane ***,we probed the L,M,and S segments of other viruses from sequencing data of other tick pools by using the putative M segment sequence of *** revealing the viromes of *** ticks,this study enhances our understanding of tick-borne viral communities in highland *** putative M segment identified in a novel uukuvirus suggests that previously identified uukuviruses without M segments should have had the same genome organization as typical *** findings will facilitate virus discovery and our understanding of the phylogeny of tick-borne uukuviruses.

关键词： Dermacentor nuttalli Qınghai Province Virome Uukuvirus M segment

Dynamic Changes of Serum Leptin and Ghrelin and Their Correlation in Buffalos around Estrus

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Animal Husbandry and Feed Science 2010年第8期2卷 15-16页

作者： LI Gong-he NING shu-fang LEI Li QIN Guang-sheng he Bao-xiang JIANG he-sheng College of Animal Science and Technology Guangxi University Nanning 530005 China

[Objective] To understand variation and correlation of serum leptin and ghrelin in buffalos around estrus. [Method] From Day 14 before estrus to Day 22 after estrus, blood was collected from 23 Murrah buffalos in a Guangxi buffalo farm. Serum levels of leptin and ghrelin were determined by ELISA. [ Result] The serum levels of leptin and ghrelin increased steadily before estrus but changed greatly in estrus. They had significantly positive correlation （ P 〈 0, 01 ）. [ Conclusion] This study provides a new way for research about mechanism of nutritional and metabolic diseases in buffalos.

关键词： Buffalos Leptin Ghrelin Correlation

Reconceptualization of immune checkpoint inhibitor-associated gastritis

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World Journal of Gastroenterology 2024年第36期30卷 4031-4035页

作者： Ying-fang Deng Xian-shu Cui Liang Wang Department of Oncology Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina Department of Gastrointestinal Oncology Surgery Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina

In recent years,with the extensive application of immunotherapy in clinical practice,it has achieved encouraging therapeutic *** enhancing clinical efficacy,however,it can also cause autoimmune damage,triggering immunerelated adverse events(irAEs).Reports of immunotherapy-induced gastritis have been increasing annually,but due to its atypical clinical symptoms,early diagnosis poses a certain ***,it can lead to severe complications such as gastric bleeding,elevating the risk of adverse outcomes for solid tumor patients if immunotherapy is ***,gaining a thorough understanding of the pathogenesis,clinical manifestations,diagnostic criteria,and treatment of immune-related gastritis is of utmost importance for early identification,diagnosis,and ***,the treatment of immune-related gastritis should be personalized according to the specific condition of each *** patients with grade 2-3 irAEs,restarting immune checkpoint inhibitors(ICIs)therapy may be considered when symptoms subside to grade *** restarting ICIs therapy,it is often recommended to use different types of *** grade 4 irAEs,permanent discontinuation of the medication is necessary.

关键词： Programmed cell death receptor-1 Programmed cell death-ligand 1 Cytotoxic T lymphocyte-associated antigen 4 Immune-related adverse events Immune-related gastritis

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可主动控制的被动调Q激光器的研究

人工晶体学报 2008年第1期37卷 5-10页

作者：段玉生霍玉晶何书芳清华大学电机工程系北京100084 清华大学电子工程系北京100084

可主动控制的被动调Q激光器(Controllable Passively Q-switched Lasers,CPQL)是一种新型脉冲激光器,它兼具主动调Q与被动调Q的优点。CPQL激光器由置于调Q激光器腔内的饱和吸收体和控制LD组成,控制LD用来控制饱和吸收体的漂白程度。CPQ... 详细信息

可主动控制的被动调Q激光器(Controllable Passively Q-switched Lasers,CPQL)是一种新型脉冲激光器,它兼具主动调Q与被动调Q的优点。CPQL激光器由置于调Q激光器腔内的饱和吸收体和控制LD组成,控制LD用来控制饱和吸收体的漂白程度。CPQL激光器的输出特性,包括脉冲能量、脉冲宽度、脉冲的产生时刻以及频率,可以通过控制LD来控制。本文给出了CPQL的原理与实验结果,,与被动调Q激光器相比,可主动控制的被动调Q激光器的性能更高,将在很多领域中有重要的应用。

关键词：固体激光器被动调Q 饱和吸收

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： Zhi-Wei Shen shu-Feng Hu Chen Zeng Wei-Qing Kong Mei-fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree