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Steiner Tree Based Optimal Resource Caching Scheme in Fog Computing 被引量:11
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作者 SU Jingtao LIN Fuhong +1 位作者 ZHOU Xianwei Lü Xing 《China Communications》 SCIE CSCD 2015年第8期161-168,共8页
Fog Computing is a new platform that can serve mobile devices in the local area. In Fog Computing, the resources need to be shared or cached in the widely deployed Fog clusters. In this paper, we propose a Steiner tre... Fog Computing is a new platform that can serve mobile devices in the local area. In Fog Computing, the resources need to be shared or cached in the widely deployed Fog clusters. In this paper, we propose a Steiner tree based caching scheme, in which the Fog servers, when caching resources, first produce a Steiner tree to minimize the total path weight(or cost) such that the cost of resource caching using this tree could be minimized. Then we give a running illustration to show how the Fog Computing works and we compare the traditional shortest path scheme with the proposed one. The outcome shows that the Steiner tree based scheme could work more efficiently. 展开更多
关键词 steiner tree resource caching fogcomputing ARCHITECTURE
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Investigation of Ancient and Large Tree Resources in Green Spaces of Urban Parks: A Case Study of Yunqizhujing Park in Hangzhou, China 被引量:5
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作者 CHU Jiamiao LAI Shuifang +1 位作者 ZHONG Tailin LI Yuan 《Journal of Landscape Research》 2012年第10期51-54,共4页
Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environmen... Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environment and enriching urban humanistic and natural landscapes, and they were also important contents of urban garden works symbolizing urban parks. A case study was carried out Yunqizhujing Park to study conservation of ancient and large trees in park green spaces of Hangzhou City, solutions to current problems were proposed, and constructive suggestions were given for the conservation of ancient and large trees in urban park green spaces. 展开更多
关键词 PARK green SPACES ANCIENT and LARGE valuable tree resourceS Current situation Problems Solutions
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Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides
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作者 Boyao Chen Kaili Liu +5 位作者 Chunsheng Wang Junjie Guo Junkun Lu Lin Chen Zhigang Zhao Jie Zeng 《Forest Ecosystems》 SCIE CSCD 2024年第4期469-479,共11页
Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species plantations.However,the responses of tree allometry to resource utilisation within the framework of inter... Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species plantations.However,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly understood.Taking into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya var.langbianensis(WC+nFN)in southern China.Six years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of B.alnoides were investigated under each treatment.Allometric variations and their relationships with space competition and nutrient-related factors were analyzed.The results showed a consistent effect of space competition on the height-diameter relationship of B.alnoides in mixtures with FN or nFN.The tree height growth of B.alnoides was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with FN.The symbiotic relationship between ectomycorrhizal fungi and B.alnoides was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal fungi.Furthermore,high space competition significantly decreased the water use efficiency(WUE)of B.alnoides,and its N use efficiency(NUE)was much lower in the FN mixtures.Structural equation modeling further demonstrated that the stem allometry of B.alnoides was affected by its NUE and WUE via changes in its height growth,and crown allometry was influenced by the mycorrhizal symbiotic relationship.Our findings provide new insights into the mechanisms driving tree allometric responses to above-and belowground resource competition and complementarity in mixed-species plantations,which are instructive for the establishment of mixed-species plantations. 展开更多
关键词 Allometric relationship resources competition and complementarity Mixed-species forest tree-fungal symbiotic relationship N_2-fixing tree species resource utilisation strategies
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Labetalol versus Hydralazine in the Management of Severe Pre-Eclampsia at Tertiary Hospitals in a Low-Resource Setting: A Randomised Controlled Trial
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作者 Uzoma Otutoaja Adeyemo Olabisi Timothy +7 位作者 Emmanuel Olumide Adewara Olufunmilayo Victoria Adebara Augustine Adebayo Adeniyi Babatunde Sunday Awoyinka Raymond Akujuobi Okere Idowu Oluseyi Adebara Adewumi Bakare Mojisola Olumide Ayankunle 《Open Journal of Obstetrics and Gynecology》 2023年第6期1058-1067,共10页
Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and ... Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and safety profile of intravenous labetalol and hydralazine in the control hypertension in severe pre-eclampsia. Materials and Methods: One hundred patients who presented with severe pre-eclampsia were randomized into two study groups. The fifty patients in each arm of the study received either intravenous labetalol or intravenous hydralazine for the control of blood pressure. Results: The mean age of the labetalol subjects was 28.6 ± 5.47 years while that of their hydralazine counterparts was 29.12 ± 5.77 years. The majority of respondents in both groups were primigravidae (76% vs. 78%) (P = 0.813). The number of doses of drug needed to significantly lower the mean systolic blood pressure was slightly lower in the labetalol group (2 doses) compared to the hydralazine group (5 doses) (t = 0.803<sup>Y</sup>, P = 0.977). The incidence of headaches which were the commonest complaints was comparable in both groups 8% and 10% of respondents respectively (P > 0.05). Conclusion: Although both intravenous labetalol and hydralazine are useful in patients with severe pre-eclampsia, the response to labetalol was better with comparable side effects. 展开更多
关键词 Blood Pressure HYDRALAZINE LABETALOL Low-resource Setting Severe Pre-Eclampsia side Effects
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Construction of Forest and Grass Industry Economic Belt Using Land Resources in Road Side Slope 被引量:1
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作者 Zhaohua ZHU Qingwang LAI +2 位作者 Guogang XU Guoliang CHI Xiaorong CHEN 《Asian Agricultural Research》 2017年第7期70-75,79,共7页
The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape.... The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape. In the design of target plant community and configuration plants,it is required to select as far as possible plants that can blossom and bear fruit or pods. Then seeds of these plants can be harvested,processed and sold,and applied for other projects,so as to develop into a complete forest and grass seed industry chain. This not only reasonably utilizes land resources,but also provides a new approach to the problem of insufficient fine forest seed sources in China. This paper discussed the use of land resources in road side slope and forest and grass seed selection and breeding technology,and elaborated the industrialized development paths for forest and grass seed industries in road side slope. Finally,it arrived at following recommendations.( i) The construction of forest and grass industry economic belt using land resources in road side slope can realize maximum land value. Building a road can help people there get rich,and the type of land and water cultivates its type of forest and grass.( ii) It can make up for the losses incurred from construction of expressway and high-speed rail or destroying forest land,and it can increase farmers' income.( iii) It can increase the supply of domestic seeds,reduce seed import,save foreign exchange,and partly solve the problem of insufficient supply of forest and grass seeds.( iv) It is able to form a complete forest and grass seed industry economic cycle chain,increase employment,and provide new approaches for enriching and benefiting farmers. 展开更多
关键词 Road side slope Land resources Forest and grass species Forest and grass seed industry economic belt
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Analysis of Cooperation between Wind Power and Load Side Resources
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作者 Xiaorui Guo Ke Wang Yaping Li 《Engineering(科研)》 2013年第9期51-55,共5页
Development of the intermittent energy is greatly promoted by change in energy, while consumption of large-scale intermittent energy is becoming a problem. With the development of smart grid technology, controllabilit... Development of the intermittent energy is greatly promoted by change in energy, while consumption of large-scale intermittent energy is becoming a problem. With the development of smart grid technology, controllability of load side resources is becoming more and more important. Based on the wave characteristics of wind power, this paper indicates that wind energy has continuous output characteristics on the hour-time scale. Through analysis on loads characteristic of industry, public facility and resident, this paper gets comprehensive response of load side resources. Considering characteristics of wind power output, combined with different load side resources and DR program, this paper suggests cooperation between wind power and load side resources on different time scales. 展开更多
关键词 WIND Power FLUCTUATION Characteristic Load side resourceS COOPERATION Adjustment Features
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Research on Optimized Allocation of English Teaching Resources Based on Network Cloud Platform
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作者 LIU Yajuan 《International English Education Research》 2018年第1期73-76,共4页
The allocation of resources in English teaching can improve the ability of resource sharing, in order to optimize the allocation of resources, so as to improve the performance of English teaching, and promote the cons... The allocation of resources in English teaching can improve the ability of resource sharing, in order to optimize the allocation of resources, so as to improve the performance of English teaching, and promote the construction of English teaching resources database, a method of optimizing the allocation of English teaching resources is proposed based on network cloud platform. Text semantic key words conceptual decision tree model is constructed for massive English teaching resources allocation, semantic information conversion method is used to compute key semantic features of English Teaching resources, the concept convergence point of English Teaching resource allocation is formed in semantic model. According to the set between the upper and lower relationship, a decision tree model of English Teaching semantic subject words is constructed, semantic conversion and information extraction are realized. English teaching resources optimization allocation simulation is taken in the cloud platform, simulation results show that the scheduling performance of English teaching resources is better, and the adaptive allocation ability of English teaching resources is stronger, and the resource utilization rate is higher. 展开更多
关键词 Network cloud platform English teaching resources Allocation: Decision tree model
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Studies on modeling for regional enterprise dynamic alliance manufacturing resource
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作者 WANG Sheng-jia GAN Yi PENG Bin 《通讯和计算机(中英文版)》 2009年第6期41-46,共6页
关键词 企业动态联盟 资源配置 计算方法 企业管理
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基于5G行业虚拟专网的海量可调节用户侧资源互动方案
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作者 李彬 林驿轩 +2 位作者 张鑫 文华杰 祝俊龙 《内蒙古电力技术》 2024年第5期23-27,共5页
为满足新型电力系统建设的需要,应对电力行业用户侧资源的不断扩张和结构变化,需要用户侧资源在互动时具有广连接、低时延的特点。基于上述问题,对当前用户侧可调节资源的需求进行了分析,结合5G行业虚拟专网的优势,给出了5G行业虚拟专... 为满足新型电力系统建设的需要,应对电力行业用户侧资源的不断扩张和结构变化,需要用户侧资源在互动时具有广连接、低时延的特点。基于上述问题,对当前用户侧可调节资源的需求进行了分析,结合5G行业虚拟专网的优势,给出了5G行业虚拟专网应用于用户侧资源互动领域的可行性,提出了基于5G虚拟专网的资源互动方案,通过虚拟专网配合柔性网络切片技术,实现对海量可调节用户侧资源的分区管理,从而支撑低时延、高质量和高安全性的可调节用户侧资源互动。 展开更多
关键词 5G 行业虚拟专网 用户侧可调节资源 海量资源互动
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考虑综合性能最优的非短视快速天基雷达多目标跟踪资源调度算法
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作者 王增福 杨广宇 金术玲 《雷达学报(中英文)》 EI CSCD 北大核心 2024年第1期253-269,共17页
合理有效的资源调度是天基雷达效能得以充分发挥的关键。针对天基雷达多目标跟踪资源调度问题,建立了综合考虑目标威胁度、跟踪精度与低截获概率(LPI)的代价函数;考虑目标的不确定、天基平台约束以及长远期期望代价,建立了多约束下的基... 合理有效的资源调度是天基雷达效能得以充分发挥的关键。针对天基雷达多目标跟踪资源调度问题,建立了综合考虑目标威胁度、跟踪精度与低截获概率(LPI)的代价函数;考虑目标的不确定、天基平台约束以及长远期期望代价,建立了多约束下的基于部分可观测的马尔可夫决策过程(POMDP)的资源调度模型;采用拉格朗日松弛法将多约束下的多目标跟踪资源调度问题转换分解为多个无约束的子问题;针对连续状态空间、连续动作空间及连续观测空间引起的维数灾难问题,采用基于蒙特卡罗树搜索(MCTS)的在线POMDP算法—POMCPOW算法进行求解,最终提出了一种综合多指标性能的非短视快速天基雷达多目标跟踪资源调度算法。仿真表明,与已有调度算法相比,所提算法资源分配更合理,系统性能更优。 展开更多
关键词 天基雷达 资源调度 多目标跟踪 部分可观测的马尔可夫决策过程 蒙特卡罗树搜索(MCTS)
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云南省古核桃资源现状研究
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作者 刘鹏程 唐文静 马方莲 《林业调查规划》 2024年第5期180-184,共5页
2017—2019年对云南省古树名木资源进行普查。结果显示,全省古核桃资源共计4765株,隶属3属4种。其中:单株古核桃2881株;古树群共21个,面积151.05 hm^(2),株数1884株。一级古树71株,占总株数的1.49%;二级古树243株,占5.10%;三级古树4451... 2017—2019年对云南省古树名木资源进行普查。结果显示,全省古核桃资源共计4765株,隶属3属4种。其中:单株古核桃2881株;古树群共21个,面积151.05 hm^(2),株数1884株。一级古树71株,占总株数的1.49%;二级古树243株,占5.10%;三级古树4451株,占93.43%。全省除西双版纳州外,其余15个州(市)、88个县(市、区)均有核桃古树分布,其中,被世界自然保护联盟列为“极危(CR)”物种的国家二级保护植物喙核桃古树25株,均分布在文山州。 展开更多
关键词 古核桃资源 单株古树 古树群 资源现状 云南省
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基于决策树的图书馆文献资源智能检索方法
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作者 宋亭 《自动化技术与应用》 2024年第4期63-66,共4页
当前图书馆文献资源类型存在差异,检索过程中排序效果差,提出一种基于决策树的图书馆文献资源智能检索方法。智能检索中需要图书馆文献资源库去除噪声,获取有效数据,使用Skip-gram模型进行文字类资源特征提取,利用卷积神经网络作为图像... 当前图书馆文献资源类型存在差异,检索过程中排序效果差,提出一种基于决策树的图书馆文献资源智能检索方法。智能检索中需要图书馆文献资源库去除噪声,获取有效数据,使用Skip-gram模型进行文字类资源特征提取,利用卷积神经网络作为图像文献资源的特征提取工具,提取过程采用Dropout机制随机断开部分网络连接,利用决策树从无规则次序数据库中推理出分类规则,计算属性与图书馆文献类型之间相关性,完成智能检索。测试结果表明:所提方法在不同数据集下的资源排序质量均优于传统检索方法。 展开更多
关键词 决策树 资源智能检索 并行计算 文献资源 资源数据库
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需求侧资源互动数字化技术发展及转型思考
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作者 李彬 耿龙妹 +4 位作者 周颖 陈宋宋 吴一敌 孙冲 马笑天 《电力信息与通信技术》 2024年第4期30-37,共8页
随着数字化技术发展及新型负荷管理系统加快建设,对需求侧可调节能力的需求越来越大,而需求侧资源数量巨大、分散较广,涉及到的终端和系统数量众多且调度难度大。为明确驱动需求侧资源互动发展的需求,文章分别从技术因素、业务因素、经... 随着数字化技术发展及新型负荷管理系统加快建设,对需求侧可调节能力的需求越来越大,而需求侧资源数量巨大、分散较广,涉及到的终端和系统数量众多且调度难度大。为明确驱动需求侧资源互动发展的需求,文章分别从技术因素、业务因素、经济因素3个方面,分析了需求侧互动领域发展的相关驱动因素。在此基础上,分别从云边协同、大模型、区块链、数字孪生等方面,分析了新型数字化技术在电力需求侧资源互动领域融合应用存在的问题及相关解决思路,从而更好地支撑需求侧资源互动业务的发展。 展开更多
关键词 需求侧资源 数字化转型 云边协同 区块链 数字孪生 多产业联动
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基于赛博孪生的天空地智能网络架构与资源分配
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作者 冯旭 秦鹏 武雪 《中国电子科学研究院学报》 2024年第5期455-460,共6页
随着海量移动和物联终端用户及其应用的爆发式涌现,迅速增加的网络流量对基于现有互联网架构设计的网络带来了严峻挑战。特别是对于空天网络,由于资源稀缺、时空分布不均,资源部署与需求不匹配,网络性能亟需优化提升。为解决以上问题,... 随着海量移动和物联终端用户及其应用的爆发式涌现,迅速增加的网络流量对基于现有互联网架构设计的网络带来了严峻挑战。特别是对于空天网络,由于资源稀缺、时空分布不均,资源部署与需求不匹配,网络性能亟需优化提升。为解决以上问题,本文构建了基于赛博孪生的天空地智能网络体系架构。该架构通过软件定义网络和资源虚拟化将物理资源抽象为虚拟资源,并采用边缘云技术将赛博孪生内生于网络边缘侧,使得网络更加灵活、具有更强的扩展性、更高的安全性。同时,本文利用匹配理论将资源分配问题转化为多参数、多玩家的匹配博弈问题,通过构建匹配模型并求解效用函数,提出了高效稳定的三边匹配算法,实现了资源分配的整体性能最优。仿真结果表明,本文方法可有效提升网络性能,实现资源的高效分配。 展开更多
关键词 赛博孪生 天空地智能网络 资源分配 三边匹配
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天水市秦州区古树资源现状分析
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作者 阮国杰 廖永峰 《甘肃林业科技》 2024年第1期66-70,共5页
应用基于移动GIS的古树名木调查APP,对天水市秦州区古树进行了调查。结果表明,秦州区现有古树479株,分属于24科31属42种。在数量特征上,柏科Cupressaceae明显占优势,株数为220株,占总数的46%;其次是豆科Leguminosae和蔷薇科Rosaceae,其... 应用基于移动GIS的古树名木调查APP,对天水市秦州区古树进行了调查。结果表明,秦州区现有古树479株,分属于24科31属42种。在数量特征上,柏科Cupressaceae明显占优势,株数为220株,占总数的46%;其次是豆科Leguminosae和蔷薇科Rosaceae,其株数分别为137株、51株,占比分别为29%、11%。在结构特征上,树高、冠幅、胸围分别集中在6.0~27.0 m、5.5~31.0 m、81~650 cm。在年龄特征上,秦州区有一级古树186株,占比39%;二级古株90棵,占比19%;三级古树203株,占比42%。秦州区生长正常的古树有51株,占比11%;生长衰弱的古树有336株,占比70%;濒危的古树有92株,占总株数的19%;未发现死亡古树。古树生长环境良好的有187株,占比39%;中等163株,占比34%;差的有129株,占比27%。综上所述,天水市秦州区古树资源较丰富,但衰弱株数量占比明显高于正常株,加强古树保护和改善古树生长环境仍然是今后的一项重点工作。 展开更多
关键词 天水市秦州区 古树 生长状况 资源分布
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常宁市古树资源调查与特征分析
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作者 陈政 祁惠 +2 位作者 彭媛媛 敬美香 王毅 《绿色科技》 2024年第17期121-126,共6页
古树是活的文物和自然的珍贵遗产,具有独特的文化价值、历史价值以及生态价值。以常宁市现存的古树资源为对象,结合实地调查数据,分别应用数据统计分析方法和ArcGIS,重点选取古树的种类特征、结构特征(胸径、树高、冠幅)、树龄与树木生... 古树是活的文物和自然的珍贵遗产,具有独特的文化价值、历史价值以及生态价值。以常宁市现存的古树资源为对象,结合实地调查数据,分别应用数据统计分析方法和ArcGIS,重点选取古树的种类特征、结构特征(胸径、树高、冠幅)、树龄与树木生长结构之间的相关性、树龄特征及其权属特征和空间分布特征6个方面进行分析。结果表明:常宁市现有古树共513株,隶属23科40属54种,其中优势种为樟树和枫香树;在结构特征方面,常宁市古树从总体上的树高、胸径和冠幅等分析均符合正态分布;古树树龄与胸径的相关性最大,且呈正相关性;在常宁市480株具有明确产权的古树中,集体产权的古树的数量最多,个人产权的古树数量为其次,国有产权的古树最少;常宁市的古树分布密集度存在明显的差异,总体上含2个高密度区和4个次密度区。常宁市的古树资源物种多样性丰富。 展开更多
关键词 古树资源调查 古树特征 常宁市
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湖北省林木种质资源保存区划研究 被引量:2
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作者 汪建亚 杨春惠 +1 位作者 吴昊 汪明 《湖北大学学报(自然科学版)》 CAS 2024年第3期330-338,共9页
林木种质资源是林业的战略资源,是生物多样性和林木育种创新的基础。本研究根据湖北省林木种质资源第二次普查数据对湖北省林木种质资源保存区划进行系统研究,结果将湖北省划分为5个林木种质资源保存区,即鄂西北山地丘陵保存区、鄂西南... 林木种质资源是林业的战略资源,是生物多样性和林木育种创新的基础。本研究根据湖北省林木种质资源第二次普查数据对湖北省林木种质资源保存区划进行系统研究,结果将湖北省划分为5个林木种质资源保存区,即鄂西北山地丘陵保存区、鄂西南山地保存区、鄂东北低山丘陵保存区、江汉平原保存区和鄂东南低山丘陵保存区,并对各区林木种质资源概况、珍稀濒危树种、常见栽培树种及需加强保护的树种资源等进行分区布局研究,同时对各区的资源保存方式给予系统建议。该区划为湖北省制定今后一段时期的林木种质资源保护利用方案、规划决策等提供科学依据,对促进我省建立不同区域的林业生态经济具有积极作用。 展开更多
关键词 林木种质资源 区划 珍稀濒危树种
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高速列车侧墙结构的决策树隔声预测模型 被引量:1
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作者 许子研 王瑞乾 +2 位作者 张学飞 任林旸 钱日成 《应用声学》 CSCD 北大核心 2024年第4期923-930,共8页
为实现对高速列车侧墙复合结构快速、精准的隔声预测,基于已有的前期大量实测数据,构建了高速列车侧墙复合结构隔声样本数据库,并提出了一种基于决策树算法的隔声预测模型,建立了结构的隔声量与材料参数之间的映射关系。首先,介绍了原... 为实现对高速列车侧墙复合结构快速、精准的隔声预测,基于已有的前期大量实测数据,构建了高速列车侧墙复合结构隔声样本数据库,并提出了一种基于决策树算法的隔声预测模型,建立了结构的隔声量与材料参数之间的映射关系。首先,介绍了原始实测样本的来源,并进行了材料组成分析、整理和归类;接着,对影响侧墙复合结构隔声性能的主要因素进行分析,开展了显著特征的筛选;最后,基于机器学习中的决策树算法对模型进行了训练和验证,并与传统有限元-统计能量分析预测方法进行了对比。结果表明:相较于传统有限元-统计能量分析模型,该决策树学习模型对高速列车侧墙复合结构隔声特性的预测准确度和预测效率均显著提高。随着将来更多样本的加入,模型还可以被进一步改进和完善,具有较大的工程实用意义和推广潜力。 展开更多
关键词 高速列车 侧墙结构 隔声预测 决策树
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郑州市中心城区古树资源特征分析及保护对策 被引量:1
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作者 唐蒲霞 刘畅 +3 位作者 王冬梦 刘艺平 雷雅凯 孔德政 《林业调查规划》 2024年第2期132-139,共8页
基于2018年郑州市古树普查数据及实地调研数据,利用Excel、ArcGIS、SPSS等软件对郑州市中心城区古树资源现状及保护现状进行分析。调查结果显示,郑州市中心城区古树共222株,属于17科26属27种,其中一级古树数量最多,三级古树数量最少,树... 基于2018年郑州市古树普查数据及实地调研数据,利用Excel、ArcGIS、SPSS等软件对郑州市中心城区古树资源现状及保护现状进行分析。调查结果显示,郑州市中心城区古树共222株,属于17科26属27种,其中一级古树数量最多,三级古树数量最少,树龄结构稳定,生长态势良好;古树资源呈聚集状态,并多分布于生态环境良好的地区;古树生长主要受环境、土壤、市政建设、养护、病虫害、人为损害等影响;古树保护中存在保护措施粗放、保护力度不够、专业队伍缺失、财政保护资金不足、古树保护宣传力度弱等问题。以期为城市中的古树名木的调查统计和保护提供了数据依据及具有科学性和实施性的策略。 展开更多
关键词 中心城区 古树资源调查 生长势 保护对策
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电子废弃物资源化回收冶炼炉渣危险特性研究 被引量:3
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作者 谢继道 周俊 +1 位作者 付红 张彩香 《有色金属(冶炼部分)》 CAS 北大核心 2024年第1期138-142,共5页
废电路板有色金属资源化回收利用过程中,会产生大量冶炼炉渣。针对《国家危险废物名录》(2021年版)实施后有色金属资源化回收冶炼炉渣的下一步安全处置方式、危险特性不明等问题,选取国内某典型电子危险废物治理企业富氧侧吹冶炼炉渣为... 废电路板有色金属资源化回收利用过程中,会产生大量冶炼炉渣。针对《国家危险废物名录》(2021年版)实施后有色金属资源化回收冶炼炉渣的下一步安全处置方式、危险特性不明等问题,选取国内某典型电子危险废物治理企业富氧侧吹冶炼炉渣为研究对象,通过采集100个样品进行元素种类和腐蚀性、毒性特性测试,得出该冶炼炉渣不具有危险废物鉴别标准规定的危险特性,可按照一般工业固体废物进行管理的结论。该结论有助于冶炼炉渣的危险特性判断和环境监管,也为冶炼炉渣类无害化处理和资源化利用提供了技术指导。 展开更多
关键词 危险废物鉴别 电子废弃物 资源化回收 富氧侧吹冶炼
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