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Theory of truth degrees of propositions in the logic system Ln^＊

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Science in china(Series F) 2006年第4期49卷 471-483页

作者： li Jun1,2 & wang guojun1,3 1. institute of mathematics, shaanxi normal university, xi’an 710062, china 2. School of Sciences, Lanzhou university of Technology, Lanzhou 730050, china 3. Research Center for Science, xi’an Jiaotong university, xi’an 710049, china institute of mathematics Shaanxi Normal University Xi’an China School of Sciences Lanzhou University of Technology Lanzhou China Research Center for Science Xi’an Jiaotong University Xi’an China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

Status of aquatic organisms resources and their environments in Yangtze River system(2017-2021)⋆

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Aquaculture and Fisheries 2024年第5期9卷 833-850页

作者： Haile Yang li Shen Yongfeng He Huiwu Tian Lei Gao Jinming Wu Zhigang Mei Nian Wei lin wang Tingbing Zhu Feifei Hu Jinling Gong Hongchun Du xinbin Duan Huatang Deng Daoqun wang Fengyue Zhu Yunfeng li Fan Wu Huijun Ru Yan Zhang Junyi li Junlin Yang Yuntao Zhou Dongdong Fang Yinping wang Danqing lin Yanping Yang Peijie li Silei liu Jian Yang Ping Zhuang Sikai wang Tao Zhang Gang Yang Wenbo Yang lilai Yuan Kun Cao Shuo Xu Huiyuan liu Zhiqiang liang Chongrui wang Hong li xiping Yuan xin Yang Yilong Fu Yanping Zhang Haixin Zhang Zhiying Tao Sheng wang xiaoping Gao Binsong Jin Kemao li Guojie wang Shenglong Jian Yingqin li Chenjiang Xue Chunyun Lei Shaowei Xue Yi Sun Bin Zhu Ke Shao xingkun Hu Meihua xiong Jun Du Bin He Tao Yan Yingying Huang Yuanchao Zou Biwen xie yongming wang Bin li Fei liu Yaoyao Zhang Fei Fan Zhijian wang Jing Huang Haoran Gu Hailong Ge Yan Dan Yan li Shuqiao wang Chuang Zhang Lu Zhou Xue wang Sheng Zeng Yan xiang Xugang He Jianhui Qin Chengxing xia Jie Hou Yifu Shi lifang Gao Zhiqiang Zhu Hongbao Shen Yun Du Xuejun Duan Jiawu xiong Deguo Yang Shaoping liu Zhaohui Ni Hui Zhang Kai liu Feng Zhao Yingren li Jianwei wang Qiwei Wei Yangtze River Fisheries Research institute Chinese Academy of Fishery SciencesWuhan430223China institute of Hydrobiology Chinese Academy of SciencesWuhan430072China Fishery Resource and Environment Research Center Chinese Academy of Fishery SciencesBeijing100141China Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization Ministry of Agriculture and Rural AffairsFreshwater Fisheries Research CenterChinese Academy of Fishery SciencesWuxi214081China East china Sea Fisheries Research institute Chinese Academy of Fishery SciencesShanghai200090China institute of Fisheries Engineering Chinese Academy of Fishery SciencesBeijing100141China Hunan Fisheries Science institute Changsha410153China Jiangxi Fisheries Research institute Nanchang330039China Jiujiang Academy of Fishery Sciences Jiujiang332000China School of life Sciences Nanchang UniversityNanchang330031China Qinghai Provincial Fishery Technology Extension Center Xining810012China Yunnan Academy of Fishery Sciences Kunming650111China institute of Hydroecology Ministry of Water Resources and Chinese Academy of SciencesWuhan430079China Fisheries institute Sichuan Academy of Agricultural SciencesChengdu611731China School of life Sciences Neijiang Normal UniversityNeijiang641100China School of life Sciences Southwest UniversityChongqing400715China Chongqing Fishery Sciences Research institute Chongqing401120China Guizhou Fisheries Research institute Guiyang550025China College of Fisheries Huazhong Agricultural UniversityWuhan430072China Hubei Fisheries Science Research institute Wuhan430070China shaanxi Fisheries Research institute Xi’an710086China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan430077China Nanjing institute of Geography and limnology Chinese Academy of SciencesNanjing210008China Central South Inventory and Planning institute of State Forestry and Grassland Administration Changsha410014China

The Yangtze River is the mother river of *** promote the aquatic ecosystem protection of the great river,the Project of Yangtze Fisheries Resources and Environment Investigation(2017-2021)supported by the Ministry of Agriculture and Rural Affairs,*** carried out by 24 institutes and universities that located in the Yangtze River basin surveys the status of(1)fish species composition and spatial distribution,(2)current fish abundance,(3)endangered fishes,(4)Yangtze finless porpoise,(5)aquatic eco-environments,(6)water-level fluctuation areas,(7)capture fisheries and recreational fisheries of the Yangtze River mainstream and 10 of its main tributaries,including Yalong River,Heng River,Min River(including Dadu River),Chishui River,Tuo River,Jialing River,Wu River,Han River,Dongting Lake and Poyang *** results showed that there were 443 fish species(belonging to 163 genus,37 families,and 18 orders)before 2017,but only 323 fish species(including 15 new recorded exotic species)were recorded in the project of *** them,Cyprinus carpio,Carassius auratus,Hypophthalmichthys molitrix,Pelteobagrus fulvidraco,Coilia brachygnathus,Silurus asotus,Saurogobio dabryi,Ctenopharyngodon idellus,Pelteobagrus nitidus,Hemiculter leucisculus,Siniperca chuatsi,Coreius heterodon,Culter alburnus,Parabramis pekinensis,and Aristichthys nobilis were the dominant species across the whole Yangtze River *** is estimated that there were 886 million individuals weighing 124.8 million kg,merely equivalent to 27.3%of the resources in 1950s,30.9%of the resources in 1960s,or 58.7%of the resources in *** the new list of protected fishes that recorded in the Yangtze River system,only 15 of 29 were collected in this project of *** gladius has been affirmed to be Extinct by International Union for Conservation of Nature(IUCN).The wild individuals of Tenualosa reevesii and Luciobrama macrocephalus have disappeared for many years and maybe have been extinct

关键词： Fishes Yangtze finless porpoise Resources Aquatic ecosystem Fisheries Background investigation Yangtze river system

Theory of truth degrees of formulas in Lukasiewicz n-valued propositional logic and a limit theorem

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Science in china(Series F) 2005年第6期48卷 727-736页

作者： li Bijing wang guojun institute of mathematics Shaanxi Normal University Xi'an 710062 China Research Center for Science Xi'an Jiaotong University Xi'an 710049 China

The concept of truth degrees of formulas in Lukasiewicz n-valued propositional logic Ln is proposed. A limit theorem is obtained, which says that the truth function τ-n induced by truth degrees converges to the integrated truth function τ when n converges to infinite. Hence this limit theorem builds a bridge between the discrete valued Lukasiewicz logic and the continuous valued Lukasiewicz logic. Moreover, the results obtained in the present paper is a natural generalization of the corresponding results obtained in two-valued propositional logic.

关键词： Lukasiewicz n-valued propositional logic truth degree limit theorem integrated truth degree

喀斯特峰丛洼地3个建群树种“植物-凋落物-土壤”系统氮同位素特征

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贵州师范大学学报（自然科学版） 2024年第1期42卷 12-18页

作者：吴凤婵蔡国俊李安定张红玉张丽敏彭熙贵州科学院贵州省生物研究所贵州贵阳550009 湖南农业大学环境与生态学院湖南长沙410128 贵州科学院贵州省山地资源研究所贵州贵阳550001 贵州师范大学生命科学学院贵州贵阳550025

以喀斯特峰丛洼地3种常见次生林及其建群树种为研究对象,测定3种林分建群种的不同器官及凋落物、土壤的氮含量及氮同位素丰度值(δ^(15)N),探讨植物-凋落物-土壤氮含量及稳定氮同位素组成变化及内在联系。结果显示:3种次生林建群种植物... 详细信息

以喀斯特峰丛洼地3种常见次生林及其建群树种为研究对象,测定3种林分建群种的不同器官及凋落物、土壤的氮含量及氮同位素丰度值(δ^(15)N),探讨植物-凋落物-土壤氮含量及稳定氮同位素组成变化及内在联系。结果显示:3种次生林建群种植物中叶片氮含量最高,茎的氮含量最低,3种次生林建群树种叶片氮含量均显著高于掉落物和土壤氮含量,0~30 cm土壤氮含量显著高于30~90 cm土壤氮含量,土壤养分主要集中于表层土壤;白栎、栓皮栎和光皮桦器官中δ^(15)N变化范围分别为-2.82‰~14.94‰、-1.37‰~9.35‰和-4.39‰~26.06‰,3种建群种器官间氮同位素组成均表现出显著差异(P15)N差异显著,3种林分中0~30 cm土壤δ^(15)N均显著低于30~60 cm和60~90 cm的土壤,δ^(15)N可能是这些群落土壤氮循环过程中的敏感指标,光皮桦叶片氮含量略大于白栎和栓皮栎,光皮桦林土壤表层δ^(15)N大于白栎林和栓皮栎林,光皮桦可能比白栎和栓皮栎更为适应喀斯特生境。

关键词：氮同位素植物-凋落物-土壤生态策略适应机制喀斯特峰丛洼地

基于多时相Sentinel-2卫星影像的冬小麦面积提取

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杭州师范大学学报（自然科学版） 2024年第2期23卷 209-216页

作者：陈雨琪席瑞陈佳麒章健高国军刘海威盛莉王福民刘占宇杭州师范大学遥感与地球科学研究院浙江杭州311121 浙江大学计算机科学与技术学院浙江杭州310058 杭州市余杭区农业技术推广中心浙江杭州310023 浙江省农业科学院数字农业研究所浙江杭州310022 浙江大学农业遥感与信息技术应用研究所浙江杭州310058 浙江大学生物灾害空间信息技术研究实验室浙江杭州310058

及时准确地提取冬小麦种植信息,对开展冬小麦农情遥感监测具有重要的意义.以杭州市余杭区冬小麦越冬期(2021-12-04)、扬花期(2022-04-08)和乳熟期(2022-05-03)Sentinel-2遥感影像为数据源,分别采用最大似然法、支持向量机、归一化差值... 详细信息

及时准确地提取冬小麦种植信息,对开展冬小麦农情遥感监测具有重要的意义.以杭州市余杭区冬小麦越冬期(2021-12-04)、扬花期(2022-04-08)和乳熟期(2022-05-03)Sentinel-2遥感影像为数据源,分别采用最大似然法、支持向量机、归一化差值植被指数(normalized difference vegetation index,NDVI)相加和相减合成运算提取冬小麦种植面积.结合冬小麦地面调查数据与实测种植面积,对不同方法的提取结果进行精度评价.结果显示,利用越冬期影像NDVI阈值将常绿植被区(茶园、林地)掩膜处理,对非常绿植被区(建筑、水体、冬小麦)扬花期与乳熟期影像NDVI值进行和值运算,是提取余杭区冬小麦种植面积的最佳方法,面积精度为91.96%,说明基于多时相遥感影像结合植被物候特征与典型地物类型,能够实现冬小麦种植面积的高精度提取.

关键词：冬小麦 Sentinel-2卫星多时相遥感影像植被分类种植面积提取

Impact of COVID-19 lockdown on the optical properties and radiative effects of urban brown carbon aerosol

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Geoscience Frontiers 2022年第6期13卷 291-301页

作者： Yong Zhang Qiyuan wang Jie Tian Yu li Huikun liu Weikang Ran yongming Han AndréS.H.Prévot Junji Cao State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Guanzhong Plain Ecological Environment Change and Comprehensive Treatment National Observation and Research Station Xi’an 710061China xi’an institute for Innovative Earth Environment Research Xi’an 710061China university of Chinese Academy of Sciences Beijing 100049China Laboratory of Atmospheric Chemistry Paul Scherrer Institute(PSI)Villigen 5232Switzerland

Intensive measurements were conducted in xi’an,china before and during a COVID-19 lockdown period to investigate how changes in anthropogenic emissions affected the optical properties and radiative effects of brown carbon(BrC)*** contribution of BrC to total aerosol light absorption during the lockdown(13%-49%)was higher compared with the normal period(4%-29%).Mass absorption cross-sections(MACs)of specific organic aerosol(OA)factors were calculated from a ridge regression *** the primary OA(POA),coal combustion OA(CCOA)had the largest MACs at all tested wave-lengths during both periods due to high molecular-weight BrC chromophores;that was followed by biomass burning OA(BBOA)and hydrocarbon-like OA(HOA).For secondary OA(SOA),the MACs of the lessoxidized oxygenated OA(OOA)species(LO-OOA)atλ=370-590 nm were higher than those of more-oxidized OOA(MO-OOA)during both periods,presumably due to chromophore *** largest contributor to BrC absorption at the short wavelengths was CCOA during both periods,but BrC absorption by LO-OOA and MO-OOA became dominant at longer wavelengths during the *** estimated radiation forcing efficiency of BrC over 370-600 nm increased from 37.5 W·gduring the normal period to 50.2 W·gduring the lockdown,and that enhancement was mainly caused by higher MACs for both LO-OOA and *** study provides insights into the optical properties and radiative effects of source-specific BrC aerosol when pollution emissions are reduced.

关键词： COVID-19 Brown carbon Mass absorption cross-section Radiative effects

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赛前准备活动:实践导向的科学证据

西安体育学院学报 2022年第5期39卷 606-617,632页

作者：黎涌明李博王雄王欣欣刘瑞东上海体育学院竞技运动学院上海200438 国家体育总局体育科学研究所北京100061 福建师范大学体育科学学院福州350108 国家体育总局训练局北京100061 北京体育大学竞技体育学院北京100084

合理的赛前准备活动策略可以帮助运动员提升比赛成绩,但准备活动效果受诸多因素的影响。对赛前准备活动的方法与机制、构成因素及其影响、实操策略和特殊手段进行综述。体温升高是准备活动产生积极作用的主要生理机制,运动神经激活、能... 详细信息

合理的赛前准备活动策略可以帮助运动员提升比赛成绩,但准备活动效果受诸多因素的影响。对赛前准备活动的方法与机制、构成因素及其影响、实操策略和特殊手段进行综述。体温升高是准备活动产生积极作用的主要生理机制,运动神经激活、能量代谢系统动员和心理准备在准备活动中同样具有重要作用。强度和持续时间、过渡期的时长和措施、场间或轮间的二次准备活动共同影响着准备活动的效果。准备活动的方案设计可以分为提升、激活和灵活、增强3个阶段,制定和实施赛前准备活动策略时需要在遵循准备活动基本科学原理的基础上,考虑项目特点、运动员个体需求和比赛情境。未来需要更多真实比赛场景下不同准备活动方法和构成因素对后续比赛表现及其机制的研究。

关键词：主动准备活动被动准备活动二次准备活动后激活增强

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直觉模糊测度的计算树逻辑

计算机科学与探索 2017年第9期11卷 1523-1530页

作者：鱼先锋李超李永明商洛学院数学与计算机应用学院陕西商洛726000 陕西师范大学计算机科学学院西安710062

建立了直觉模糊Kripke结构(intuitionistic fuzzy Kripke structure,IFKS)模型,提出了基于直觉模糊Kripke结构的直觉模糊测度空间理论,阐述了IFKS的一系列性质。证明了任一路径转移的直觉模糊可达度(intuitionistic fuzzy probability,IFP)为初始状态的直觉模糊测度与各转移的IFP所取下确界,任一状态出发的所有路径上路径转移的IFP为所有路径可达度的上确界。给出了路径转移矩阵P及其传递闭包P^+的概念,给出了通过计算路径转移矩阵传递闭包,计算路径可达度的算法,并分析了算法的复杂度。提出了直觉模糊计算树逻辑(intuitionistic fuzzy computation tree logic,IFPCTL)理论,讨论了一组IFPCTL、可能测度计算树逻辑(possibilistic computation tree logic,PoCTL)和经典计算树逻辑(computation tree logic,CTL)公式的等价性。最后给出了一组等价的IFPCTL和PoCTL公式以及一组不等价的IFPCTL和CTL公式。

关键词：直觉模糊Kripke结构直觉模糊测度直觉模糊计算树逻辑模型检测

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人体运动的最大乳酸稳态:机制与影响

西安体育学院学报 2022年第4期39卷 485-493页

作者：李博章凌凌黎涌明福建师范大学体育科学学院福州350108 上海体育学院体育教育训练学院上海200438 上海财经大学体育教学部上海200433 国家体育总局体育科学研究所北京100061

人体能量代谢随运动强度的增加而改变,无氧阈被用以描述能量代谢由低强度向高强度转换过程中的临界强度。在众多无氧阈相关指标中,最大乳酸稳态(MLSS)常被当作评价无氧阈的金标准。最大乳酸稳态是持续运动中血乳酸相对稳定且可长时间维... 详细信息

人体能量代谢随运动强度的增加而改变,无氧阈被用以描述能量代谢由低强度向高强度转换过程中的临界强度。在众多无氧阈相关指标中,最大乳酸稳态(MLSS)常被当作评价无氧阈的金标准。最大乳酸稳态是持续运动中血乳酸相对稳定且可长时间维持的最高输出功率/速度(MLSSw)和血乳酸浓度(MLSSc)。MLSS的测试结果受运动方式、实验对象和测试方案等多个因素影响。人体运动的MLSS是乳酸产生、转运和利用综合作用的结果,乳酸穿梭学说解释了不同运动强度下人体的血乳酸反应和MLSS的生理学基础。对MLSS历史发展、生理机制和影响因素的梳理有助于更好地理解人体的能量代谢过程,更为准确地开展有氧能力的评价和制定耐力训练计划。

关键词：无氧阈乳酸阈最大乳酸稳态乳酸穿梭