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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

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青钱柳扦插育苗试验

林业科技开发 2014年第5期28卷 124-127页

作者：李先民方升佐刘晶晶南京林业大学林学院南京210037

以青钱柳硬枝和嫩枝作为扦插材料,分别探讨了基质加温、ABT1和GGR6应用、基质和空气湿度控制、以及来自不同部位的插条等对扦插生根的影响。结果表明,基质加温可以显著提高青钱柳硬枝扦插生根率,经400mg/L ABT1+400 mg/L GGR6处理6 h后... 详细信息

以青钱柳硬枝和嫩枝作为扦插材料,分别探讨了基质加温、ABT1和GGR6应用、基质和空气湿度控制、以及来自不同部位的插条等对扦插生根的影响。结果表明,基质加温可以显著提高青钱柳硬枝扦插生根率,经400mg/L ABT1+400 mg/L GGR6处理6 h后,进行基质加温的扦插生根率达35.6%;不同的扦插基质湿度及扦插空气湿度对青钱柳插穗生根率影响显著,青钱柳夏季嫩枝扦插以空气湿度控制在70%左右和V草炭土∶V珍珠岩=1∶1基质、湿度控制在30%左右为佳。青钱柳属难生根树种,从生根率角度考虑,夏季嫩枝扦插选择枝条中上部剪制插穗为佳,硬枝扦插选择枝条基部剪制插穗为宜。

关键词：青钱柳插穗类型生根率环境因子促根剂

“双一流”建设背景下高校知识产权管理中的问题及举措——以南京林业大学为例

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江苏科技信息 2019年第30期36卷 33-35页

作者：崔光彩方升佐南京林业大学

在我国"双一流"建设从理论走向政策实践的背景下,各高校只有对"双一流"建设的意蕴进行深层次的分析,才能把握其本质,寻找正确的对策,提升自己的科研竞争力,而知识产权管理工作又是推动高校科技创新发展的重要手段。文章以南京林业大学为... 详细信息

在我国"双一流"建设从理论走向政策实践的背景下,各高校只有对"双一流"建设的意蕴进行深层次的分析,才能把握其本质,寻找正确的对策,提升自己的科研竞争力,而知识产权管理工作又是推动高校科技创新发展的重要手段。文章以南京林业大学为例,通过对知识产权管理工作中存在的不足与问题,以及近年来专利申请、授权转化情况的分析,探索应对措施,以期为知识产权管理体系的完善与管理水平的提高提供参考。

关键词：高校知识产权管理

On Hamiltonian Property of Cayley Digraphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 547-556页

作者： fang DUAN Qiong-xiang HUANG School of Mathematics Science Xinjiang Normal UniversityUrumqi 830017China College of Mathematics and Systems Science Xinjiang UniversityUrumqi 830017China

Let G be a finite group generated by S and C(G,S) the Cayley digraphs of G with connection set *** this paper,we give some sufficient conditions for the existence of hamiltonian circuit in C(G,S),where G=Zm×H is a semiproduct of Zmby a subgroup H of *** particular,if m is a prime,then the Cayley digraph of G has a hamiltonian circuit unless G=Zm×*** addition,we introduce a new digraph operation,called φ-semiproduct of Γ1by Γ2and denoted by Γ1×Γ_φΓ2,in terms of mapping φ:V(Γ2)→{1,-1}.Furthermore we prove that C(Zm,{a})×_φ C(H,S) is also a Cayley digraph if φ is a homomorphism from H to{1,-1} ≤ Zm~*,which produces some classes of Cayley digraphs that have hamiltonian circuits.

关键词： Cayley digraphs hamiltonian circuit external semidirect product

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青钱柳叶总黄酮超声辅助提取工艺优化

农业机械学报 2009年第2期40卷 130-134,75页

作者：冯宗帅吴彩娥方升佐杨万霞杨剑婷李婷婷南京林业大学森林资源与环境学院南京210037

为研究以乙醇为溶剂超声波辅助提取青钱柳叶总黄酮的工艺,在单因素试验的基础上,采用四因素二次回归正交旋转组合设计,以液料比、超声处理时间、超声功率、溶剂体积分数为考察因素,优选了超声波辅助提取青钱柳叶总黄酮的最佳工艺。结果... 详细信息

为研究以乙醇为溶剂超声波辅助提取青钱柳叶总黄酮的工艺,在单因素试验的基础上,采用四因素二次回归正交旋转组合设计,以液料比、超声处理时间、超声功率、溶剂体积分数为考察因素,优选了超声波辅助提取青钱柳叶总黄酮的最佳工艺。结果表明各因素对提取率的影响大小依次为:超声处理时间、溶剂体积分数、液料比、超声功率。最佳工艺条件为液料比55 mL/g,超声处理时间34 min,超声功率720 W,溶剂体积分数60%,在此最佳条件下,总黄酮的得率为86.63%,优化工艺稳定,提取率也较高,试验验证结果与模型预测值相符。

关键词：青钱柳叶总黄酮超声提取

Trudinger–Moser Inequalities on a Closed Riemann Surface with a Symmetric Conical Metric

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2263-2284页

作者： Yu fang Yun Yan YANG College of Teacher Education Quzhou UniversityQuzhou 324003P.R.China Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This is a continuation of our previous work(*** ***.,20,1295–1324,2020).Let(Σ,g)be a closed Riemann surface,where the metric g has conical singularities at finite *** G is a group whose elements are isometries acting on(Σ,g).Trudinger–Moser inequalities involving G are established via the method of blow-up analysis,and the corresponding extremals are also *** extends previous results of Chen(***.,1990),Iula–Manicini(Nonlinear Anal.,2017),and the authors(2020).

关键词： Trudinger-Moser inequality blow-up analysis conical singularity

Concept, configuration, and application of on-board nanogrids for use in electric vehicles

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Science China(Technological Sciences) 2024年第7期67卷 2053-2073页

作者： ZHAO Bing LI Yong WU fang WAN JiangHu CAI JiuQing YANG HaiTao LIU fang College of Electrical and Information Engineering Hunan UniversityChangsha 410082China Wuhan Second Ship Design and Research Institute Wuhan 430000China School of Automation Central South UniversityChangsha 410083China

Against the backdrop of increasingly serious climate change, researchers are attempting to extend macroscale carbon reduction research to smaller scales. With the rapid development and widespread application of electric vehicles(EVs), an effective approach for carbon reduction based on EVs has the potential to be developed. To coordinate and manage the EV platform in diverse application scenarios, the concept of an on-board nanogrid(OBNG), in which a nanogrid is combined with the EV, is proposed and defined, and the characteristics summarized. A configuration that includes a physical layer with the on-board hardware system;an information layer for logical control, energy management, and communication coordination;and an application layer that can cope with different working environments is proposed. A detailed introduction to the basic architecture and management mode of each layer is provided along with information concerning the relevant technologies for coordinated operation. New ideas and approaches to improve the existing performance are proposed, and finally, combined with a background of smart and low-carbon cities, major application scenarios are envisioned.

关键词： electric vehicle nanogrid energy management hybrid energy storage power electronics converter

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青钱柳胸径生长和木材密度的地理变异规律

南京林业大学学报（自然科学版） 2017年第4期41卷 1-5页

作者：孙戴妍尚旭岚洑香香方升佐南方现代林业协同创新中心南京林业大学林学院江苏南京210037

【目的】青钱柳是我国特有的单种属植物和具有开发利用前景的珍贵树种,通过探讨青钱柳胸径生长和木材基本密度的地理变异及径向变异规律,为青钱柳材用优良地理种源筛选提供依据。【方法】以天然分布的不同地理种源青钱柳为研究对象,选... 详细信息

【目的】青钱柳是我国特有的单种属植物和具有开发利用前景的珍贵树种,通过探讨青钱柳胸径生长和木材基本密度的地理变异及径向变异规律,为青钱柳材用优良地理种源筛选提供依据。【方法】以天然分布的不同地理种源青钱柳为研究对象,选择群落中的优势木和亚优势木,用生长锥在树高1.3 m(胸径位置)处同一方位钻取单株木芯,共计钻取木芯197条,测定22个地理种源各单株木芯的胸径部年轮生长量和木材基本密度。【结果】22个青钱柳地理种源的胸径生长存在极显著差异(P<0.01)。林龄为20年生时,22个青钱柳地理种源胸径平均生长量为18.6 cm,变幅在16.7~20.9 cm,总体呈现出从西北到东南生长量递增的趋势;青钱柳的胸径连年生长量在0.69~1.24 cm,随林木年龄递增,其连年生长量在波动中逐渐下降。不同地理种源青钱柳的平均木材基本密度存在极显著差异(P<0.001),22个地理种源青钱柳木材基本密度的平均值为0.470 g/cm^3,变幅在0.400~0.510 g/cm^3;不同生长年轮间平均基本密度存在显著差异,其木材的平均基本密度随生长年轮的递增呈现径向递增的趋势,但前18 a其木材基本密度不存在显著差异。相关分析表明,青钱柳胸径生长与木材基本密度间存在显著线性负相关(P<0.05)。【结论】不同地理种源青钱柳的胸径生长和木材基本密度存在显著差异,为青钱柳材用优良地理种源筛选提供了良好空间和可能性。

关键词：青钱柳木材基本密度地理种源生长年轮径向变异

Spatial-temporal patterns and evolution of carbon storage in China's terrestrial ecosystems from 1980 to 2020

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Science China Earth Sciences 2024年第10期67卷 3270-3287页

作者： Shaojian WANG Shijie ZHOU Chuanglin fang School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Analyzing the changes in carbon storage in terrestrial ecosystems caused by land use changes is a crucial part of exploring the carbon cycle. In addition, enhancing carbon storage in terrestrial ecosystems is an effective and environmentally friendly measure to sequester anthropogenic carbon emissions, which is significant for achieving carbon neutrality and curbing global climate change. This paper uses land use data and carbon density tables with the In VEST model to obtain a carbon storage distribution map of China. It further applies land use response elasticity coefficients, Theil index multi-stage nested decomposition, and spatial autocorrelation analysis to examine the spatial-temporal patterns, causes of changes, and evolution characteristics of carbon storage in terrestrial ecosystems from 1980 to 2020. The results show that the temporal changes in China's carbon storage generally present an inverted S-curve, with an initial rapid decline followed by a slower decrease. Spatially, it features high levels in the northeast, low levels in the northwest, and a uniform distribution in the central and southern *** disturbance of land use type changes on terrestrial ecosystem carbon storage has been effectively mitigated. The significant reduction in grassland area in the Southwest region is the main source of carbon storage loss during the study period, and the encroachment of construction land on arable land in large urban agglomerations is one of the important causes of carbon storage loss. The Theil index multi-stage nested decomposition results indicate that the overall difference in carbon storage in China has decreased, while differences among cities within provinces and among counties within cities have increased. The influence of natural factors on the distribution of carbon storage is weakening, whereas the impact of human activities is becoming more profound, enhancing its influence on the spatial distribution of carbon storage in China. From 198

关键词： Terrestrial ecosystem carbon storage Carbon density Land use change InVEST model Spatiotemporal pattern