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On Periodic Oscillation and Its Period of a Circadian Rhythm Model
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作者 Miao Feng Chen Zhang 《Communications on Applied Mathematics and Computation》 2022年第3期1131-1157,共27页
We theoretically study periodic oscillation and its period of a circadian rhythm model of Neurospora and provide the conditions for the existence of such a periodic oscillation by the theory of competitive dynamical s... We theoretically study periodic oscillation and its period of a circadian rhythm model of Neurospora and provide the conditions for the existence of such a periodic oscillation by the theory of competitive dynamical systems.To present the exact expression of the unique equilibrium in terms of parameters of system,we divide them into eleven classes for the Hill coefficient n=1 or n=2,among seven classes of which nontrivial periodic oscillations exist.Numerical simulations are made among the seven classes and the models with the Hill coefficient n=3 or n=4 to reveal the influence of parameter variation on periodic oscillations and their periods.The results show that their periods of the periodic oscillations are approximately 21.5 h,which coincides with the known experiment result observed in constant darkness. 展开更多
关键词 rhythm model Km-type competition system Periodic oscillation PERIOD
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Classification and Visualization of Surrounding Rock Mass Stability Based on Multi-Dimensional Cloud Model
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作者 Liming Xue Wenlong Shen +2 位作者 Zhixue Zheng Jiming Chen Hongtao Liu 《Energy Engineering》 EI 2021年第6期1799-1810,共12页
The classification of the stability of surrounding rock is an uncertain system with multiple indices.The Multidimensional Cloud Model provides an advanced solution through the use of an improved model of One-dimension... The classification of the stability of surrounding rock is an uncertain system with multiple indices.The Multidimensional Cloud Model provides an advanced solution through the use of an improved model of One-dimensional Cloud Model.Setting each index as a one-dimensional attribute,the Multi-dimensional Cloud Model can set the digital characteristics of each index according to the cloud theory.The Multi-dimensional cloud generator can calculate the certainty of each grade,and then determine the stability levels of the surrounding rock according to the principle of maximum certainty.Using this model to 5 coal mine roadway surrounding rock examples and comparing the results with those of One-dimensional and Two-dimensional Cloud Models,we find that the Multi-dimensional Cloud Model can provide a more accurate solution.Since the classification results of the Multidimensional Cloud Model are difficult to be presented intuitively and visually,we reduce the Multi-dimensional Cloud Model to One-dimensional and Two-dimensional Cloud Models in order to visualize the results achieved by the Multi-dimensional Cloud Model.This approach provides a more accurate and intuitive method for the classification of the surrounding rock stability,and it can also be applied to other types of classification problems. 展开更多
关键词 multi-dimensional cloud model surrounding rock stability UNCERTAIN VISUALIZATION
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亚热带森林小麂的空间分布及活动节律的区域性差异 被引量:1
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作者 马钲焱 李佳琦 +6 位作者 万雅琼 李言阔 单继红 王振宇 邵瑞清 张超 李笑颖 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第2期222-232,共11页
小麂(Muntiacus reevesi)是偶蹄目鹿科麂属动物,在我国种群数量丰富,分布广泛,但关于小麂在不同区域的空间分布及活动节律的差异性研究相对较少。为掌握小麂的活动节律及其影响因素,2018年3月至2019年2月利用红外相机技术对江西省桃红... 小麂(Muntiacus reevesi)是偶蹄目鹿科麂属动物,在我国种群数量丰富,分布广泛,但关于小麂在不同区域的空间分布及活动节律的差异性研究相对较少。为掌握小麂的活动节律及其影响因素,2018年3月至2019年2月利用红外相机技术对江西省桃红岭梅花鹿国家级自然保护区、九岭山国家级自然保护区和齐云山国家级自然保护区的小麂进行了监测,每个保护区的红外相机数量均为60台,相机工作日分别为9692、9659、14582 d,小麂的独立有效照片数分别为603、665、1032张,并运用单季节占域模型估算了各地区小麂的占域率和探测率,分析了海拔、坡度、植被覆盖度以及距水源地距离等环境变量对小麂活动规律以及分布范围的影响。结果表明,桃红岭保护区和九岭山保护区的小麂偏好于海拔较低、坡度较小、植被指数较低、距水源地距离较近的区域;齐云山保护区的小麂偏好于海拔较高、坡度较大、植被指数较高、距水源地距离较近的区域。小麂为明显的晨昏性动物,日活动高峰出现在06:00—08:00和17:00—19:00。其日活动节律在齐云山存在显著季节差异,桃红岭保护区和九岭山保护区则无显著季节差异,各保护区之间的年活动节律不存在显著差异。该研究结果有助于进一步了解小麂的活动节律模式及其季节性变化,进一步了解小麂在自然状态下的生态习性,为这一物种的保护和管理提供数据支撑。 展开更多
关键词 小麂 占域模型 红外相机 活动节律
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唐家河国家级自然保护区同域分布六种偶蹄类动物的活动节律与空间利用
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作者 韩一敏 肖梅 +7 位作者 何梦楠 李明富 侯蓉 吴鹏程 何芳 谌利民 胡杰 陈鹏 《兽类学报》 CAS CSCD 北大核心 2024年第5期598-610,共13页
了解群落中具有相似生态位的同域分布物种的时空分布是群落生态学研究的主要内容之一。本研究于2021年1—12月在四川唐家河国家级自然保护区境内应用红外相机技术进行大中型哺乳动物的监测,共布设红外相机82台,总相机工作日为18710 d。... 了解群落中具有相似生态位的同域分布物种的时空分布是群落生态学研究的主要内容之一。本研究于2021年1—12月在四川唐家河国家级自然保护区境内应用红外相机技术进行大中型哺乳动物的监测,共布设红外相机82台,总相机工作日为18710 d。采用核密度估计法(Kernel density estimation)和占域模型(Occupancy model)分析冷季和暖季该保护区内6种偶蹄类的时空分布。研究结果表明:(1)毛冠鹿(Elaphodus cephalophus)和小麂(Muntiacus reevesi)在冷季和暖季的日活动节律高度重叠(△≥0.80),中华扭角羚(Budorcas tibetana)、中华斑羚(Naemorhedus griseus)、中华鬣羚(Capricornis milneedwardsii)和野猪(Sus scrofa)为中度重叠(△值为0.50~0.80);(2)毛冠鹿、小麂、中华扭角羚、中华斑羚和野猪的日活动模式均为双峰型,且都具有晨昏习性,中华鬣羚偏夜行性,日活动模式为多峰型;(3)在冷季,中华扭角羚的占域率最高(0.70),在暖季,中华斑羚的占域率最高(0.96),中华鬣羚在冷季和暖季的占域率均最低,分别是0.18和0.19;(4)海拔、坡度、坡向、距水源地距离及距道路距离是影响这6种偶蹄类空间分布的重要因子。研究显示,唐家河国家级自然保护区内6种偶蹄类动物的活动节律与空间利用在冷季和暖季具有一定的差异性。本研究结果初步揭示了不同季节偶蹄类动物的时空分布特征及影响因素,为今后该区域制定针对性的保护管理措施提供科学依据。 展开更多
关键词 红外相机 偶蹄类动物 季节性 活动节律 空间利用 占域模型
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面部三维生理特征点在睡眠剥夺中的疲劳检测
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作者 李敬强 房秋 +1 位作者 樊天辰 马龙 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第9期2753-2762,共10页
睡眠不足、生理节律紊乱是导致交通运输岗位人员疲劳的重要因素,随着值勤“刷脸”技术的兴起,及时识别岗位人员疲劳状态是安全风险防范关口前移的必要举措。为深入探索面部疲劳的三维变化,通过30 h睡眠剥夺实验,基于主成分分析(PCA)法... 睡眠不足、生理节律紊乱是导致交通运输岗位人员疲劳的重要因素,随着值勤“刷脸”技术的兴起,及时识别岗位人员疲劳状态是安全风险防范关口前移的必要举措。为深入探索面部疲劳的三维变化,通过30 h睡眠剥夺实验,基于主成分分析(PCA)法融合面部双侧曲率特征,提出皱纹严重程度指数(WSI),结合主观疲劳评估、精神运动警觉度测试和客观心率(HR)监测方法,综合判断受试者的面部疲劳程度。结果表明:在睡眠剥夺条件下,WSI变化和疲劳的波动特征明显,整体呈逐渐升高趋势;30 h实验数据显示,WSI变化和主观疲劳指数、反应时的波动趋势有较强相关性(P<0.01)和HR的波动趋势有一定的关联性(P<0.05)。基于WSI指数将疲劳划分为4个等级,从三维生理特征的角度验证面部疲劳静态检测的可行性,研究结果为疲劳快速检测技术提供了新思路。 展开更多
关键词 面部特征 疲劳检测 睡眠剥夺 三维建模 昼夜节律
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电磁感应驱动下闭环呼吸控制系统中的混合节律及其动力学分析
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作者 陈雪丽 夏露源 +1 位作者 王智慧 段利霞 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第18期54-68,共15页
Pre-Botzinger复合体是哺乳类动物呼吸节律起源的关键部位.外周化学感受器可通过监测血液中氧气和二氧化碳浓度的变化,显著影响呼吸节律.本文基于pre-Botzinger复合体神经元,同时考虑运动池、肺容积、肺氧、血氧以及化学感受器等因素,... Pre-Botzinger复合体是哺乳类动物呼吸节律起源的关键部位.外周化学感受器可通过监测血液中氧气和二氧化碳浓度的变化,显著影响呼吸节律.本文基于pre-Botzinger复合体神经元,同时考虑运动池、肺容积、肺氧、血氧以及化学感受器等因素,建立了电磁感应驱动的闭环呼吸控制模型.研究发现,在不同电磁感应驱动下,系统的缺氧反应受到磁流反馈系数的控制.通过分岔分析和数值模拟,揭示了磁流反馈系数对呼吸节律的恢复能力具有显著影响,并阐明了产生不同缺氧反应的动力学机制.此外,研究发现在电磁感应驱动下,闭环系统中混合簇放电节律能够自动恢复的条件为缺氧扰动前后的分岔结构完全相同;而当缺氧扰动前后的分岔结构不同,系统中混合簇放电节律则不能自动恢复.对于较轻电磁感应驱动下不能自动恢复的情形,适当增大磁流反馈系数能使系统自动恢复,这与Hopf分岔、极限环的鞍结分岔密切相关.本研究有助于理解呼吸中枢与外周化学感受反馈的相互作用对呼吸节律的影响以及外部感应对缺氧反应的控制作用. 展开更多
关键词 呼吸节律 闭环呼吸控制模型 分岔分析 电磁感应
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基于潮汐理论模型的护理干预联合垂直律动训练对输尿管结石钬激光碎石术患者的作用
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作者 常梦琦 孟亚雯 +3 位作者 聂云 刘岩 吕翠礼 马伟明 《护理实践与研究》 2024年第8期1254-1259,共6页
目的分析输尿管结石钬激光碎石患者在围术期开展基于潮汐理论模型的护理干预联合垂直律动训练的临床效果,探讨基于潮汐理论模型的护理干预联合垂直律动训练对碎石术患者尿动力学指标的影响。方法选取2020年1月—2023年1月徐州市中心医... 目的分析输尿管结石钬激光碎石患者在围术期开展基于潮汐理论模型的护理干预联合垂直律动训练的临床效果,探讨基于潮汐理论模型的护理干预联合垂直律动训练对碎石术患者尿动力学指标的影响。方法选取2020年1月—2023年1月徐州市中心医院泌尿外科收治的80例输尿管结石患者为研究对象,按组间基本资料具有可比性的原则分成对照组和观察组,各40例。对照组实施常规围术期护理,观察组实施基于潮汐理论模型护理干预联合垂直律动训练。比较两组患者的情绪状态、尿动力学指标、并发症、自护能力等。结果护理干预前两组患者抑郁自评量表(SDS)评分、焦虑自评量表评分(SAS)比较差异无统计学意义(P>0.05),护理干预后观察组患者SDS评分、SAS评分均低于对照组,差异有统计学意义(P<0.05)。护理干预前两组患者最大尿流率、残余尿量比较差异无统计学意义(P>0.05),护理干预后观察组患者最大尿流率高于对照组,而残余尿量低于对照组,差异有统计学意义(P<0.05)。观察组患者并发症发生率低于对照组,差异有统计学意义(P<0.05)。护理干预前两组患者的自我护理能力测定量表(ESCA)评分比较差异无统计学意义(P>0.05),护理干预后观察组患者的ESCA评分高于对照组,差异有统计学意义(P<0.05)。结论基于潮汐理论模型的护理干预联合垂直律动训练可有效调节输尿管结石钬激光碎石患者的情绪状态,提高自我护理能力,从而有利于改善其尿动力学指标,降低术后并发症风险。 展开更多
关键词 输尿管结石 钬激光碎石术 潮汐理论模型 垂直律动训练 尿动力学
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基于合金和温度模型的自动精炼技术
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作者 张华 《河北冶金》 2024年第9期44-50,共7页
LF精炼是钢水处理过程的重要工序,唐山中厚板公司精炼部分环节由操作工人工完成,操作工凭借经验控制精炼生产,容易产生较大的人为误差,既增加工作量,又影响质量稳定性。为消除人为误差,提高钢水质量稳定性,同时满足生产节奏的需求,对LF... LF精炼是钢水处理过程的重要工序,唐山中厚板公司精炼部分环节由操作工人工完成,操作工凭借经验控制精炼生产,容易产生较大的人为误差,既增加工作量,又影响质量稳定性。为消除人为误差,提高钢水质量稳定性,同时满足生产节奏的需求,对LF精炼冶炼流程进行了研究,设计出了一套自动冶炼系统。按照业务逻辑和技术逻辑该系统分为冶金工艺流程、辅料计算模型、合金加料模型、冶金温度模型,并对每个模块应用冶金热力学、冶金动力学、数学建模技术和人工智能大数据技术作为理论依据和实现方法,最后有机串联协同这些模块,满足紧张的生产节奏,实现LF精炼的全自动化智能化生产,进而降低成本,提高钢水质量。系统上线后,推动了LF炉钢水冶炼自动化、操作流程化、标准化,且随着LF精炼冶炼流程的不断优化,钢水稳定性稳步提升,实现了精炼工序所有环节的自动控制,钢水精炼终点成分和温度命中率有效提高。 展开更多
关键词 合金加料 温度模型 自动精炼 生产节奏 智能化 成分模型
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加热炉炉温优化设定模型的研究与应用
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作者 李小新 《智慧工厂》 2024年第1期60-64,共5页
加热炉炉温设定模型是在遵循加热炉操作规程基础上且满足板坏加热质量和工厂整体生产节奏,根据板坏在炉内的升温情况,结合板坏的加热工艺及专家经验,对加热炉各段炉温进行优化设定。这对板坏加热工艺制度的执行,减轻加热炉烧火工劳动强... 加热炉炉温设定模型是在遵循加热炉操作规程基础上且满足板坏加热质量和工厂整体生产节奏,根据板坏在炉内的升温情况,结合板坏的加热工艺及专家经验,对加热炉各段炉温进行优化设定。这对板坏加热工艺制度的执行,减轻加热炉烧火工劳动强度,减少产品质量的波动,都有不可替代的提升作用。炉温设定模型包括模型优化计算和专家经验调整。 展开更多
关键词 加热炉 生产节奏 工艺制度 模型优化计算 炉温设定 专家经验
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Sedimentary characteristics and depositional model of a Paleocene-Eocene salt lake in the Jiangling Depression,China 被引量:10
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作者 余小灿 王春连 +6 位作者 刘成林 张招崇 徐海明 黄华 谢腾骁 李皓楠 刘锦磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1426-1435,共10页
We studied the sedimentary characteristics of a Paleocene-Eocene salt lake in the Jiangling Depression through field core observation,thin section identification,scanning electron microscopy,and X-ray diffraction anal... We studied the sedimentary characteristics of a Paleocene-Eocene salt lake in the Jiangling Depression through field core observation,thin section identification,scanning electron microscopy,and X-ray diffraction analysis.On the basis of sedimentary characteristics we have summarized the petrological and mineralogical characteristics of the salt lake and proposed 9 types of grade IV salt rhythms.The deposition shows a desalting to salting order of halite-argillaceous-mudstone-mud dolostonemud anhydrock-glauberite-halite.The relationship among grade IV rhythms,water salinity and climate fluctuations was analyzed.Based on the analysis of the relationship between boron content and mudstone color and by combining the mineralogy and sedimentary environment characteristics,we propose that the early and late Paleocene Shashi Formation in the Jiangling Depression was a paleolacustrine depositional environment with a high salt content,which is a representation of the shallow water salt lake depositional model.The middle Paleocene Shashi Formation and the early Eocene Xingouzui Formation were salt and brackish sedimentary environments with low salt content in a deep paleolake,which represents a deep salt lake depositional model. 展开更多
关键词 Paleocene-Eocene salt lake salt rhythm depositional model Jiangling Depression
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A MULTISCALE MECHANICAL MODEL FOR MATERIALS BASED ON VIRTUAL INTERNAL BOND THEORY 被引量:6
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作者 Zhang Zhennan Ge Xiurun Li Yonghe 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第3期196-202,共7页
Only two macroscopic parameters are needed to describe the mechanical properties of linear elastic solids, i.e. the Poisson's ratio and Young's modulus. Correspondingly, there should be two microscopic parameters to... Only two macroscopic parameters are needed to describe the mechanical properties of linear elastic solids, i.e. the Poisson's ratio and Young's modulus. Correspondingly, there should be two microscopic parameters to determine the mechanical properties of material if the macroscopic mechanical properties of linear elastic solids are derived from the microscopic level. Enlightened by this idea, a multiscale mechanical model for material, the virtual multi-dimensional internal bonds (VMIB) model, is proposed by incorporating a shear bond into the virtual internal bond (VIB) model. By this modification, the VMIB model associates the macro mechanical properties of material with the microscopic mechanical properties of discrete structure and the corresponding relationship between micro and macro parameters is derived. The tensor quality of the energy density function, which contains coordinate vector, is mathematically proved. From the point of view of VMIB, the macroscopic nonlinear behaviors of material could be attributed to the evolution of virtual bond distribution density induced by the imposed deformation. With this theoretical hypothesis, as an application example, a uniaxial compressive failure of brittle material is simulated. Good agreement between the experimental results and the simulated ones is found. 展开更多
关键词 virtual multi-dimensional internal bond material property dimensionality multiscale modeling molecular dynamics virtual internal bond
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Multi-dimensional database design and implementation of dam safety monitoring system 被引量:1
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作者 Zhao Erfeng Wang Yachao +2 位作者 Jiang Yufeng Zhang Lei Yu Hong 《Water Science and Engineering》 EI CAS 2008年第3期112-120,共9页
To improve the effectiveness of dam safety monitoring database systems, the development process of a multi-dimensional conceptual data model was analyzed and a logic design wasachieved in multi-dimensional database mo... To improve the effectiveness of dam safety monitoring database systems, the development process of a multi-dimensional conceptual data model was analyzed and a logic design wasachieved in multi-dimensional database mode. The optimal data model was confirmed by identifying data objects, defining relations and reviewing entities. The conversion of relations among entities to external keys and entities and physical attributes to tables and fields was interpreted completely. On this basis, a multi-dimensional database that reflects the management and analysis of a dam safety monitoring system on monitoring data information has been established, for which factual tables and dimensional tables have been designed. Finally, based on service design and user interface design, the dam safety monitoring system has been developed with Delphi as the development tool. This development project shows that the multi-dimensional database can simplify the development process and minimize hidden dangers in the database structure design. It is superior to other dam safety monitoring system development models and can provide a new research direction for system developers. 展开更多
关键词 dam safety multi-dimensional database conceptual data model database mode monitoring system
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QoS Routing Algorithm with Multi-Dimensions for Overlay Networks 被引量:1
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作者 戴慧珺 曲桦 赵季红 《China Communications》 SCIE CSCD 2013年第10期167-176,共10页
Overlay networks have emerged as a useful approach to providing a general framework for new applications and services that are to be implemented without significantly changing the IP-layer network infrastructure.Overl... Overlay networks have emerged as a useful approach to providing a general framework for new applications and services that are to be implemented without significantly changing the IP-layer network infrastructure.Overlay routing has been used as an alternative to the default best effort Internet routing for the absence of end-to-end Quality of Service(QoS). While the former has recently been investigated, the conflict of QoS restraints and resource optimization remains unsolved. Recent studies have shown that overlay paths can give better latency, loss rate and TCP throughput. In this paper, a multi-dimensional QoS objective model based on the analysis of multiple QoS constraints has been presented, and a routing algorithm to optimise the overlay resource of its nodes and links is then proposed.In fact, the algorithm obtained multiple QoS values using probability theory to achieve the routing according to the multi-dimensional QoS objective vector of the QoS objective model. Simulation results reveals that the algorithm works better than other existing algorithms in balancing the network resources, and applications with stringent QoS requirements could be run. 展开更多
关键词 OVERLAYS QoS routing multi-di- mensional QoS objective model multi-dimensional QoS objective vector
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Least squares fitting of coordinate parameters model
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作者 YU Sheng-wen~(1), DONG Jun~(2), WANG Ai-min~(3) (1. Shandong University of Science and Technology, Tai’an 271019, China 2. Bao’an Coal Mine of Huaning Group, Hua’ning, Tai’an 271000, China 3. The Plan Bureau of Laiwu, Laiwu 272000, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期197-199,共3页
This paper starts with untime-diversification of the time-diversification deformation model and gives displacement distribution model of untime-diversification and simplifies further the study of deformation model. Th... This paper starts with untime-diversification of the time-diversification deformation model and gives displacement distribution model of untime-diversification and simplifies further the study of deformation model. The paper discusses the problem of least squares fitting of coordinate parameters model—parameters of deformation model. During discussion, the basic means of cubic B splines and two steps of multidimensional disorder datum fitting are adopted which can make fitting function calculated mostly approximate coordinate parameters model and it can make calculation easier. 展开更多
关键词 COORDINATE parameter model least SQUARES FITTING two STEPS of multi-dimensionAL disorder data curve FITTING
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MULTI-DIMENSIONAL MARKOV CHAIN–BASED ANALYSIS OF CONFLICT PROBABILITY FOR SPECTRUM RESOURCE SHARING
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作者 张轶 喻莉 张利维 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期207-215,共9页
In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimens... In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimensional Markov chain model is developed to analyze the performance of the proposed scheme. Meanwhile, performance metrics are derived. Numerical results show that the proposed scheme can effectively reduce the forced termination probability, blocking probability and spectrum utilization. 展开更多
关键词 multi-dimensional Markov chain model independent Poisson process negative exponential distribution forced termination probability blocking probability
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Research and implementation on multi-dimension trust evaluation method with web service
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作者 Mao Hongyan Qi Zhengwei 《High Technology Letters》 EI CAS 2011年第3期252-258,共7页
Integrating with practical e-commerce application, this paper introduces a novel multi-dimension evaluation method to depict and calculate the trust values. The multi-dimension evaluation metrics include functional an... Integrating with practical e-commerce application, this paper introduces a novel multi-dimension evaluation method to depict and calculate the trust values. The multi-dimension evaluation metrics include functional and nonfunctional properties and corresponding weights. The continuous measurement values and the Markov chain mechanism are adopted to compute the trust value and detect the malicious behaviors. The current evaluation has larger influence factor on the next transaction behavior. A trust model is implemented with web service which consists of publication, filtrating, calculating and storage center. It is easily extended and the user only defines each property and its weights according to specific requirements, then the trust values are got. In order to conveniently manage and avoid the dead-lock, some constraint rules are proposed. The results show that the method based on multi-dimension can reflect objectively the dynamic change of trust values. 展开更多
关键词 multi-dimension measurement trusting model Markov chain mechanism web service
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Application of PPE Model in Land Adaptability Appraisal in Small Basin Based on RAGA
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作者 ZHOU Jiang-hong LEI Ting-wu WANG Yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期155-159,共5页
The paper applies multi-dimension to lower technology-projection pursuit evaluation model in the conservation of water and soil discipline domain, optimizes the projection direction using the improved acceleration gen... The paper applies multi-dimension to lower technology-projection pursuit evaluation model in the conservation of water and soil discipline domain, optimizes the projection direction using the improved acceleration genetic algorithms, transforms the multi-dimensional data target to lower sub-space, and values soil adaptability of Dongdagou basin in Keshan County by searching the optimal projection direction and the projection function data. The paper provides a new notion and method for the conservation of water and soil in small basin. 展开更多
关键词 from multi-dimensional to lower technology projection pursuit evaluation model small basin land adaptability appraisal
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THE CONDENSATION OF THE BEAUTY ON THEMODELLING OF THE ART OF FASHION PERFORMANCE
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作者 皇甫菊含 《苏州大学学报(工科版)》 CAS 1993年第S2期54-60,共7页
To embody the pattern and sytle of costume is the key purpose of fashion performance.But the modelling is an important link of fashion performance. About how to fully expressthe pattern and style of costume through ex... To embody the pattern and sytle of costume is the key purpose of fashion performance.But the modelling is an important link of fashion performance. About how to fully expressthe pattern and style of costume through external form and inner entiment of the modelling.this paper pointed out three factors such as point and surface. idea and rhythm and expound-ed and proved that the three factors are unseparate organism. 展开更多
关键词 expound IMAGINATION EMOTION rhythm FASHION BEAUTY MUSICAL modelling pointed subtle
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模型与数据双驱动的失眠脑电alpha节律研究 被引量:1
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作者 李强 潘敏 成波 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第3期359-366,共8页
失眠是一种典型的睡眠障碍,以入睡困难、睡眠深度或频度过短、早醒及睡眠时间不足等为主要特征。临床上一些失眠患者在快速眼动(REM)睡眠期会出现明显的脑电alpha节律活动增强现象,但发生这一现象的内在机制尚不清楚。基于此,从计算神... 失眠是一种典型的睡眠障碍,以入睡困难、睡眠深度或频度过短、早醒及睡眠时间不足等为主要特征。临床上一些失眠患者在快速眼动(REM)睡眠期会出现明显的脑电alpha节律活动增强现象,但发生这一现象的内在机制尚不清楚。基于此,从计算神经科学的角度出发,结合Liley神经计算模型与临床失眠脑电数据,探索失眠患者在REM期典型放电节律的发生机制。首先,设计一种基于马尔可夫蒙特卡洛的Liley模型关键参数的自动选择与估计方法;其次,结合失眠患者脑电数据,确定影响alpha节律发放的模型关键参数,并据此给出失眠患者REM期脑电alpha节律活动增强的机制假设:抑制性突触活动强度的降低会诱导alpha节律活动的增强。所获结果对于改善失眠患者的睡眠质量并控制病情发展具有一定的指导作用和临床价值。 展开更多
关键词 失眠 脑电alpha节律 Liley模型 关键参数
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鄂西南日本柳杉人工林单木生长规律与模型研究 被引量:1
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作者 周鸣惊 唐志强 +4 位作者 来羽 杨佳伟 戴薛 李健 张家来 《湖南林业科技》 2023年第1期31-38,共8页
为分析鄂西南日本柳杉(Cryptomeria japonica)人工林的生长过程,以石板岭林场39年生日本柳杉人工林为研究对象,选取12株标准木进行树干解析,采用Logistic、Richards、Schumacher等6种经验生长模型拟合了生长过程。结果表明:日本柳杉在... 为分析鄂西南日本柳杉(Cryptomeria japonica)人工林的生长过程,以石板岭林场39年生日本柳杉人工林为研究对象,选取12株标准木进行树干解析,采用Logistic、Richards、Schumacher等6种经验生长模型拟合了生长过程。结果表明:日本柳杉在鄂西南适应性强,39年生日本柳杉胸径、树高、材积总生长量分别为23.2 cm、18.9 m、0.383 9 m3;其速生期在第6—第24年,树高、胸径平均生长量峰值均在第24年;胸高形数0.55~6.32,呈反“J”形,第12年后胸高形数趋于稳定;胸径、树高、材积的最佳生长方程均为理查德方程;材积连年生长量始终高于平均生长量,林分未达到数量成熟。 展开更多
关键词 日本柳杉 生长规律 生长模型 数量成熟 鄂西南
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