Spatial pattern of tree diversity and evenness across forest types in Majella National Park,Italy

Background： Estimation of tree diversity at broader scale is important for conservation planning. Tree diversity should be measured and understood in terms of diversity and evenness, two integral components to describe the structure of a biological community. Variation of the tree diversity and evenness with elevation, topographic relief, aspect, terrain shape, slope, soil nutrient, solar radiation etc. are well documented. Methods： Present study explores the variation of tree diversity （measured as Shannon diversity and evenness indices） of Majella National Park, italy with five available forest types namely evergreen oak woods, deciduous oak woods, blacWaleppo pine stands, hop-hornbeam forest and beech forest, using satellite, environmental and field data. Results： Hop-hornbeam forest was found to be most diverse and even while evergreen Oak woods was the lowest diverse and even. Diversity and evenness of forest types were concurrent to each other i.e. forest type which was more diverse was also more even. As a broad pattern, majority portion of the study area belonged to medium diversity and high evenness class. Conclusions： Satellite images and other GIS data proved useful tools in monitoring variation of tree diversity and evenness across various forest types. Present study findings may have implications in prioritizing conservation zones of high tree diversity at Majella.

STUDY ON THE METHOD FOR EFFECTIVELY QUICK DETECTING THE EVENNESS OF A KNITTED FABRIC

In this paper,the relations between the parameters of stitch structure and the needle penetra-tion force,and the method by using the needle penetration force detected to evaluate the looplength and evenness of knitted fabric indirectly are analysed and discussed.A microcomputer system with a needle sensor and author’s program are used as a pick up setcombined with a data analysis system,for sampling and analysing the needle penetration forcedata.A lot of experimental research work has been done for knitted fabric of some kinds of knittedstitch and loop length.As a summary of this study,some conclusions can be drawn from the linearregression between the needle penetration force and the loop length.Then,the size and evenness ofthe loop length of knitted fabric can be indicated indirectly by detecting the value and variance ofneedle penetration force.It offers an effective method to detect and evaluate the evenness of knit-ted fabric with an efficiently high speed.

Research on Evenness of Woollen Cashmere Yarn

Parameters influencing the evenness of the woollen cashmere yarn were analyzed, and fifty batches of yams with fineness of 38.5 tex were used to study the quality control parameters in relation to the evenness. Through statistical analysis, the models of yarn evenness were built. Moreover, the relationship between the evenness of spinning yarn and roving yarn was also investigated. The results showed that a positive correlation existed between them, and the mount of thin place per kilometer was the most important factor which could influence the evenness of woollen cashmere yam. The influence of the amount of neps and thick place on the yam evenness was indistinctive. The conclusions obtained would be helpful to improve the precontrol ability on yarn evenness.

Morphology and PDE based inspection method of yarn evenness

In yarn evenness inspection based on image processing,due to serious noise,morphological method can not separate yarn from the blackboard entirely.In order to solve this problem,this paper proposes a denosing method that combines morphology with the image decomposition based on partial differential equation(PDE).Before denosing automatical skew detection is introduced to avoid the calculation error caused by image tilting.The experimental results show that the hairiness can be removed completely,and the characteristics of yarn can be reserved.The inspection result is well coincided with visual assessment.

Approaches for a 3D assessment of pavement evenness data based on 3D vehicle models

Pavements are 3D in their shape. They can be captured in three dimensions by modern road mapping equipment which allows for the assessment of pavement evenness in a more holistic way as opposed to current practice which divides into longitudinal and transversal evenness. It makes sense to use 3D vehicle models to simulate the effects of 3D surface data on certain functional criteria like pavement loading, cargo loading and driving comfort. In order to evaluate the three criteria mentioned two vehicle models have been created： a passenger car used to assess driving comfort and a truck-semitrailer submodel used to assess pavement and cargo loading. The vehicle models and their application to 3D surface data are presented. The results are well in line with existing single-track （planar） models. Their advantage over existing 1D/2D models is demonstrated by the example of driving comfort evaluation. Existing ＂geometric＂ limit values for the assessment of longi- tudinal evenness in terms of the power spectral density could be used to establish corre- sponding limit values for the dynamic response, i.e. driving comfort, pavement loading and cargo loading. The limit values are well in line with existing limit values based on planar vehicle models. They can be used as guidelines for the proposal of future limit values. The investigations show that the use of 3D vehicle models is an appropriate and meaningful way of assessing 3D evenness data gathered by modern road mapping systems.

早青与晚青乌龙茶的挥发性成分差异

为探明鲜叶不同采摘时段对乌龙茶香气化学特征的影响,本研究将铁观音早青与晚青按传统工艺加工成乌龙茶,运用气相色谱-质谱法分析鲜叶和乌龙茶的挥发性成分,比较早青茶与晚青茶中挥发性成分的差异。结果表明,晚青茶所含挥发性组分总量比早青茶少28.3%,醇类化合物的含量及占比均处优势,尤其是异植醇和反-橙花叔醇。挥发性成分在鲜叶与乌龙茶中的组成特征差异较大,醇类和酸类化合物在鲜叶中的占比相近,但在乌龙茶中二者差异较大;早青与晚青包含56种共有挥发性成分,比其乌龙茶的共有成分多4种,但在鲜叶与乌龙茶共有42种成分中十六烷酸、二氢猕猴桃内酯、反-橙花叔醇、异植醇等受加工工艺的影响明显,且变化幅度较大。可见晚青与早青中挥发性成分的分布特征相异,晚青茶优于早青茶且清香突出。

Spatio-temporal evolution analysis of landscape pattern and habitat quality in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 based on InVEST model

Habitat quality is an important indicator for evaluating the quality of ecosystem.The Qinghai Province section of the Yellow River Basin plays an important role in the ecological protection of the upper reaches of the Yellow River Basin.To comprehensively analysis the alterations of habitat quality in the Qinghai Province section of the Yellow River Basin,this study utilized the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to calculate the habitat quality index and analyze the spatio-temporal variation characteristics of habitat quality in the study area from 2000 to 2022,and calculated seven landscape pattern indices(number of patches,patch density,largest patch index(LPI),landscape shape index(LSI),contagion index(CONTAG),Shannon diversity index,and Shannon evenness index)to research the variation of landscape pattern in the study area.The results showed that the number of patches,patch density,LPI,LSI,Shannon diversity index,and Shannon evenness index increased from 2000 to 2022,while the CONTAG decreased,indicating that the landscape pattern in the Qinghai Province section of the Yellow River Basin changed in the direction of distribution fragmentation,shape complexity,and heterogeneity.The average value of the habitat quality index in the Qinghai Province section of the Yellow River Basin from 2000 to 2022 was 0.90.Based on the value of habitat quality index,we divided the level of habitat quality into five categories:lower(0.00-0.20),low(0.20-0.40),moderate(0.40-0.60),high(0.60-0.80),and higher(0.80-1.00).Most areas were at the higher habitat quality level.The lower habitat quality patches were mainly distributed in Longyang Gorge and Yellow River-Huangshui River Valley.From 2000 to 2022,the habitat quality in most areas was stable;the increase areas were mainly distributed in Guinan County,while the decrease areas were mainly distributed in Xining City,Maqen County,Xinghai County,Qumarleb County,and Darlag County.To show the extent of habitat quality variation,we calculated Sen index.The results showed that the higher habitat quality area had a decrease trending,while other categories had an increasing tendency,and the decreasing was faster than increasing.The research results provide scientific guidance for promoting ecological protection and high-quality development in the Qinghai Province section of the Yellow River Basin.

基于优化奇偶重构法的光伏阵列自适应重构技术设计

对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,重构效果差的缺点。所提出的方法将光伏阵列分为自由重构模块和固定重构模块,根据不同的阴影情况调整连接方式,确定最佳的连接关系,并与Arrow So Du ku,Zig-zag,OEC三种方法进行仿真实验对比,仿真结果表明,经过OOEC重构后的光伏阵列输出功率明显提高,光伏阵列的PU输出特性曲线更加趋向于单峰,并且从失配损耗,功率提升百分比,性能比,均衡指数上看来,OOEC有着更好的性能。

成纱段摩擦应力对亚麻棉混纺纱线质量的影响

针对如何有效经济地提升亚麻棉混纺纱线质量问题,提出了物理集聚纱体表面有害毛羽的方法。通过在成纱段设计和安装旋转式沟槽专件,对纱体施加摩擦应力,增强对纤维的控制力,达到提升纱线质量的目的。理论模型分析可知,摩擦应力的介入导致纱线的捻度传递出现梯度差异,随着摩擦应力的增加,梯度差异增加。在摩擦力和扭转力的协同作用下,纱体表面纤维被捕捉和加捻,达到集聚纤维须条的目的,从而减少毛羽。实验结果证实:随着摩擦应力的增加,纱线毛羽降低的幅度越高,有害毛羽最多可降低35.5%。然而,过大的摩擦应力会恶化条干,最高为1.6%。其中粗节上升7.3%,棉结上升4.8%,而强力没有明显变化。通过计算优化施加的摩擦应力,协同捻度差效应,达到提升纱线质量的目的。

基于弱化算子的黑龙江省人口老龄化灰色预测

近年来,黑龙江省人口老龄化率高于全国,老龄人口规模持续上升,对医疗保障体系、劳动力资源结构以及养老服务体系等产生影响,因此,研究黑龙江省人口老龄化的预测问题具有十分重要的现实意义。针对黑龙江省人口老龄化的灰色特性,提出一种结合一阶弱化算子优化的均值GM(1,1)预测模型,对黑龙江省老龄人口发展趋势进行预报。以2006—2021年间的黑龙江省老龄人口原始数据为样本,构建基于一阶弱化算子均值GM(1,1)的黑龙江省人口老龄化预测模型,并与基于均值GM(1,1)的黑龙江省人口老龄化预测模型精度进行对比分析。结果表明:黑龙江省老龄人口的一阶弱化算子均值GM(1,1)预测模型精度高于传统的均值GM(1,1)模型,说明一阶弱化算子的均值GM(1,1)模型能够提高黑龙江省老龄人口预报精度。

项群理论视角下高校体育课程思政建设的实证研究

该研究在项群理论启示之下,对高校体育课程项目的运动规律和内在联系进行研究,结合高校体育课程思政的建设现状,在二者融合发展建设可行性分析的基础上,以德育属性为依据,将高校体育课程项目进行同属项群分类,并进行不同体育项群的思政育人内涵的深入挖掘,从教学目标设定、教学内容融合、教学方法选择、教学评价方式4个维度提出高校体育课程思政推进路径。

“功在国家,利在自己”:新中国初期的保本保值储蓄

1950年3月,国家统一财经工作之后,物价趋稳,人民币币值进一步稳定。为消除民众对物价能否长期稳定的顾虑,国家银行在折实储蓄的基础上开办了保本保值储蓄。保本保值储蓄的适宜举办,对民众来说,改善了生活,增强了储蓄兴趣,初步建立了储蓄习惯;对于国家来说,聚集了社会闲散资金,支援了新中国国家建设。同时,保本保值储蓄的实施,为货币储蓄奠定了基础,也扩大了人民政府的政治影响,体现了新制度的优越性。

简单的深邃:罗伯特·弗罗斯特的《雪夜林边逗留》

罗伯特·弗罗斯特认为“诗歌以喜悦开篇,以智慧作结”。当喜悦在诗歌中遇见智慧时,诗人强烈的情感和深邃的思想往往显得貌似简单,或许这就是弗罗斯特所谓“情感发现了思想而思想又找到了文字”的时候。弗罗斯特的《雪夜林边逗留》一诗发表于1923年3月7日,一百多年来,它不仅脍炙人口,而且早已成为全世界英美诗歌教学与研究者所津津乐道的不朽诗篇。本文从这首弗罗斯特自己“最喜爱的诗”及其“隐秘性愉悦”、意象化遣词造句、“一位提喻诗人”、“一年中最黑暗的夜晚”、“躲避困惑的片刻清净”等视角重读此诗,进而阐释弗罗斯特“简单的深邃”这一诗歌创作特点。

奇偶相干态信号场下的量子关联和纠缠

为了实现两原子之间的非经典关联,借助于电磁诱导光透明(electromagnetically induced optical transparency,EIT)机制,利用量子态的映射技术,研究原子系综内两原子的量子关联和纠缠。结果表明:分别通过测量扰动刻画的量子关联和并发度刻画的量子纠缠,发现它们都能够被绝热地生成,但是,随着平均光子数的增加,二者的演变完全不同。随着平均光子数的增加,无论信号场是奇数相干态还是偶数相干态,它们都有利于量子关联的生成。对于奇相干态信号场,量子纠缠随着光子数的增加而逐渐减小;对于偶相干态信号场,量子纠缠却经历了一个先增加后减小的过程。系综内原子个数的增加,使得原子间的退相干加剧,从而导致量子关联和纠缠都被削弱。

Pell方程组x^(2)-40y^(2)=1与y^(2)-Dz^(2)=9的公解

设D=2p_(1)⋯p_(s)(1≤s≤4),其中p_(1),⋯,p_(s)是互不相同的奇素数。主要利用奇偶分析、同余、递归序列以及Pell方程解的性质等初等方法,对Pell方程组x^(2)-40y^(2)=1与y^(2)-Dz^(2)=9的公解进行研究。得出当D≠2×7×103时,该方程组仅有平凡解(x,y,z)=(±19,±3,0);当D=2×7×103时,除了平凡解(x,y,z)=(±19,±3,0)外,还有非平凡解(x,y,z)=(±27379,±4329,±114)。研究结果丰富了这类Pell方程组整数解的研究内容。

等氮条件下施用不同有机肥对玉米田大型土壤动物种群的影响

为从土壤动物角度研究土壤改良和耕地质量提升,探究等氮条件下不同有机肥和化肥配施对玉米田大型土壤动物的影响,试验设定猪粪(处理3)、羊粪(处理4)、菌渣(处理5)、易腐垃圾(处理6)有机肥、化肥(处理2)和空白(处理1)共6个处理,对不同施肥处理不同土层的土壤环境及大型土壤动物的分布情况开展调查,并对其大型土壤动物多样性进行了分析。结果表明,在玉米田土壤中共捕获到膜翅目、蜘蛛目、半翅目和弹尾目等10个类群的大型动物,以膜翅目和蜘蛛目为优势类群。各处理组的Shannon-Wiener多样性指数从高到低依次为处理6、处理3、处理4、处理5、处理2和处理1。其中,易腐垃圾有机肥处理的Shannon-Wiener多样性指数和均匀度指数最高,猪粪有机肥处理次之。4种有机肥处理的Shannon-Wiener多样性指数均比纯化肥和空白处理高,可见有机肥料的施用增加了土壤含水量,提高了有机质及全氮含量,有利于土壤动物群落数量和多样性增加,有利于农业可持续发展。

“拼死吃河豚”的饮食史意义

中国人食用河豚的庶民“拼死吃河豚”、士人“值得一死”试河豚、市民普及吃河豚历史三阶段性的观点;庶民一直是历史上河豚食用者的主体族群,兼有活命原始义和享受美味伴生义的两重意义。社会精英阶层的染指河豚基本不属于果腹需求,初期时段则主要是心理好奇、情感刺激和个性张扬需求,美味安慰是后期发展,并因之促成了市民普及吃河豚历史发展。对中国人食河豚中毒、防毒、解毒历史记录做了深入分析,指出症结历史局限的社会原因。

基于改进型双模分数阶重复控制器的高速磁悬浮电机谐波电流抑制

主动磁悬浮轴承系统的转子不平衡和传感器跳动会使系统产生谐波电流,从而导致谐波振动。重复控制器能同时抑制同频和倍频谐波,但传统重复控制器必须确保控制系统的采样频率与实际转频之比为整数,极大地限制了其适用性。为解决此问题,设计了一种改进型双模分数阶重复控制器。采用拉格朗日插值法将分数阶变为整数,解决了重复控制的非整数延迟问题;通过双支路独立地消除奇偶次谐波,第1次、2次、3次、4次和5次谐波分别降低了87.9%、61.3%、86.9%、36.9%和85.3%。仿真和试验结果验证了改进型重复控制器对谐波电流抑制的精确性和有效性。

纱线条干均匀度检测技术的研究进展

纱线条干均匀度是评估纱线质量和质地的重要指标,对纺织品质量、性能以及加工工艺有着重要影响,因此准确快速地测定条干均匀度在纺织工业中具有重要意义。通过回顾国内外相关文献,综合讨论了电容式、光电式和图像处理3种条干均匀度检测技术,并对各自的研究进展进行了详细阐述。重点讨论了条干均匀度检测技术的准确度、评价指标和技术要领等,分析了影响条干均匀度检测技术发展的相关因素,并从理论依据、研究方法和应用评价等角度讨论了条干均匀度检测技术目前存在的问题,为纺织工业中的条干均匀度检测提供一定参考,从而促进纺织行业的工业生产和技术进步。

基于两平晶三面互检的折射率均匀性测量方法

结合奇偶函数理论,提出了一种基于两平晶三面干涉测量平晶折射率均匀性的方法。该方法通过两块平晶3个表面之间的组合测量,对折射率均匀性引入的误差进行分部求解,生成4个随机波面作为初始3个表面面形和折射率均匀性误差,对其中的均匀性误差复原,结果与初始值仅相差0.6×10-6,残差与平晶表面面形的低频信息无关,仅取决于折射率均匀性本身的旋转不变项。在100 mm口径Zygo干涉仪上完成了两平晶折射率均匀性检测实验。同时通过三平晶透射法对同一块平晶的折射率均匀性进行检测,将两种方法的测量结果进行对比。结果表明两平晶方法获得的折射率均匀性结果与透射法获得的折射率均匀性波面形状相同,指标结果仅相差0.2×10-6,波面偏差峰谷值相差3 nm。分析了影响评估精度的误差项,旋转角度误差与对准误差的影响在实验精度条件下,均方根偏差均小于1 nm。实验结果表明所提出的两平晶三面互检方法能够有效地对平晶的折射率均匀性进行测量。