Effect of spatial pattern on nutrient reduction in the Liaohe Delta

The effect of spatial pattern on the nutrient reduction is investigated based on the spatial simulation model developed for the study area of the Liaohe Delta, China. Four scenarios are designed to test the effect of different landscape components on the nutrient reduction in the reed marsh: Canal density, reed area size, reed area shrinking pattern, and pumping station position. Based on a spatial model designed for the study area, the nutrient reduction in each case of these scenarios is simulated. The results indicate that each factor brings less than 10% change in the total nutrient reduction rate. More canals will not help much to improve nutrient reduction. Smaller areas are more efficient than larger ones. The shrinkage pattern is better than others in keeping a higher nutrient reduction rate. It is also more efficient to keep the pumping station near the border of the area to be irrigated. These conclusions provide theoretical supports to strategy makers for local land use planning, and contribute to the understanding of the relationship between landscape patterns and functions.

Study on cumulative effects of different cultivation patterns on wetland soil environment

Cumulative effects on wetland soils under different cultivation patterns were analyzed in the experimental fields of the Ecological Experimental Station of Mire-wetlands in Sanjiang Plain. The results suggested that the paddy field combined with the glebe to act on the soil environment. Under the combination of natural and anthropological factors, the cultivation of the paddy field and the glebe obviously related with different kinds of fertility factors of soil. The remarkable relation among organic matter, total nitrogen and available nitrogen reflected the fertilization of the soil at some extent.

Tunable acoustic radiation pattern assisted by effective impedance boundary

The acoustic wave propagation from a two-dimensional subwavelength slit surrounded by metal plates decorated with Helmholtz resonators （HRs） is investigated both numerically and experimentally in this work. Owing to the presence of HRs, the effective impedance of metal surface boundary can be manipulated. By optimizing the distribution of HRs, the asymmetric effective impedance boundary will be obtained, which contributes to generating tunable acoustic radiation pattern such as directional acoustic beaming. These dipole-like radiation patterns have high radiation efficiency, no finger- print of sidelobes, and a wide tunable range of the radiation pattern directivity angle which can be steered by the spatial displacements of HRs.

Pattern-Prototype Effects of Processing Familiar Metonymy in Sentential Context

This study conducted an eye-tracking experiment on processing different patterns of Chinese familiar metonymy in sentential contexts.It analyzes five eye-tracking measures concerning the processing of metonymy.The results indicate that different patterns of metonymy experience different processing processes under a sentential-context condition,and results in prototype effects.The main finding is that Spatial Part&Whole metonymy is more prototypical than other three patterns of metonymy,i.e.,Container and Contained,Location and Located,Entity and Adjacent Entity,and that the effect of metonymy pattern on the processing is stable and observable.It concludes that contextual information facilitates the processing of non-prototypical metonymy,but restrain the processing of prototypical metonymy.

The effect of different irrigation patterns on rice yield and water consumption

The ecological and physiological water require-ment of rice and rice yield was studied underthree irrigation patterns, which were A: moistirrigation, remains 70-90% of saturated soilwater content except 3-4 cm deep water layerin tillering stage in paddy; B: flood irrigation,remains 4-5 cm deep water layer except 80%relative water content in the late tillering stage

Influencing Factors and Urbanization Effects of the Spatial Pattern of Floating Population in Anhui Province

Based on the population census data,this paper analyzed the influencing factors and urbanization effects of the floating population in Anhui Province using ArcGIS spatial analysis,factor analysis,multiple liner regression,and spatial autocorrelation,and reached the following conclusions:① From 2000 to 2010,the floating population in Anhui Province was concentrated in cities dotted the Huai River and the Yangtze River,and Hefei City absorbed the most inter-provincial floating population and intra-provincial floating population.② The overall economic strength had the greatest impact on attracting floating population,while the income level factor has less impact on attracting floating population.The overall economic strength and the strength of science,education,culture,and health of prefecture-level cities in Anhui Province were more attractive to the intra-provincial floating population and less attractive to the inter-provincial floating population.③ Population mobility promoted urbanization.Large cities could attract more migrants from counties.The urban population system in Anhui Province was generally developing towards the concentration of large cities,while the proportion of the county population in the total population was decreased.

具有避难效应和非局部被捕食效应的捕食系统斑图形态研究

具有避难效应的捕食–食饵反应扩散模型是一类重要的种群动力学模型,其斑图形态为研究种群数量时空分布提供关键信息。建立了一个具有避难效应和非局部被捕食效应的Leslie-Gower捕食–食饵反应扩散模型。首先,通过线性稳定性分析和Turing失稳分析分别推导出正平衡点局部稳定及Turing失稳的条件。其次,通过数值模拟分别展示了食饵斑图形态随非局部被捕食效应和避难效应变化而演化的情况。最后,通过分析捕食者和食饵种群空间平均密度与非局部被捕食效应和避难效应参数的变化关系,研究表明:食饵种群数量随着非局部效应的增强而增大,捕食者种群数量随着非局部效应的增强而减少,说明非局部被捕食效应在促进食饵密度增长的同时,抑制捕食者种群的增长;捕食者和食饵种群的数量均随避难效应的增强而增大,说明较强避难效应对食饵种群具有庇护作用,并能促进捕食者和食饵种群持续共存。结论有助于人们更好地从数学层面理解非局部效应和避难效应对捕食者和食饵种群斑图形态影响的规律。

流通数字化赋能全国统一大市场建设的机理与效应研究

建设全国统一大市场是加快构建新发展格局的基础支撑和内在要求。本文聚焦流通数字化发展对全国统一大市场建设的影响,实证检验流通数字化赋能全国统一大市场建设的传导机制和异质特征。研究发现,流通数字化发展能够显著促进全国统一大市场建设,且该研究结论具有较强的稳健性。机制检验结果表明,流通数字化发展能够通过加快创新要素流动、扩大企业规模、释放消费潜力等途径促进全国统一大市场建设。异质性检验结果表明,在基础设施水平、城镇化率和人口集聚程度较高地区,流通数字化对全国统一大市场建设的促进作用较为明显。进一步研究发现,流通数字化与统一大市场之间存在基于基础设施、城镇化率和人口集聚水平的门槛效应。本文研究结论为我国进一步加快流通产业的数字化转型、破除区域间要素流动壁垒、推进统一大市场建设提供了经验证据。

Long-term effects of pattern scan laser pan-retinal photocoagulation on diabetic retinopathy in Chinese patients: a retrospective study

●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of 29 patients(53 eyes)with severe non-proliferative DR(SNPDR)or proliferative DR(PDR)who received PRP and follow-up at our hospital from 2008 to 2013.Sixteen patients(29 eyes)received PASCAL PRP and 13 patients(24 eyes)received 100-ms conventional laser PRP.●RESULTS:After long-term follow-up(mean,min-max days:719.8,290-1666 for PASCAL PRP vs 743.5,240-1348 for conventional PRP,P=0.569),patients receiving PASCAL PRP required fewer photocoagulation sessions than the conventional PRP group(2.6±1.0 vs 3.9±0.9,P<0.01).Best corrected visual acuity(BCVA)was reduced slightly in PASCAL PRP group while reduced significantly in conventional PRP group.At last visit,24 eyes in the PASCAL group(88.9%)and 21 eyes in the conventional group(91.7%)were improved or stable.Two eyes in PASCAL PRP group(7.4%)and 3 eyes in the conventional PRP group(12.5%)developed vitreous hemorrhage or vitreous fibrovascular proliferation.●CONCLUSION:PASCAL PRP is as effective and may be more conducive to maintaining visual acuity with less treatment sessions for DR treatment compared to conventional laser PRP.

东营凹陷利津北带砂砾岩体储层测井评价

东营凹陷利津北带砂砾岩体储层矿物组分复杂,物性参数解释精度低,油、干层界限难以界定。基于测井、录井、试采、分析化验等资料,采用交会图版识别和雷达图形模式识别岩性方法,较好地区分了砂砾岩体岩性。在岩性识别、含油产状分析、试采资料分析基础上,分别建立了砾岩类和碳酸盐岩类有效储层的物性和电性下限。结合试采资料,建立了利津北带砂砾岩体有效储层分级解释图版与评价标准。分别建立了砾岩类和碳酸盐岩类储层孔隙度和渗透率参数模型,为利津北带复杂砂砾岩体储层提供定量评价方法。该研究成果在利津北带砂砾岩体投产井中得到了应用验证,效果良好。

基于印花效果的四色经提花面料产品研发

为研发具有印花效果的四色经提花面料新产品,对产品的花稿设计、纱线配置和编织工艺3方面内容进行了研究与实践。通过设计合适的花稿图案,选用5.56tex/36f的加捻涤纶低弹色纱,色彩分别为红、蓝、黄、黑4种颜色的纱线作为经纱,8.33tex/72f的白色或黑色涤纶色纱作为纬纱,运用重经组织结构使这4种不同颜色经纱形成不同的浮长,利用经纱混色配置的方式实现花稿图案的丰富色彩,研发出色彩丰富且立体感强、面密度轻、环保性能好、具有印花效果的轻薄型提花面料。

新冠疫情以来中国的出生人口波动解析

持续三年的新冠疫情对全球人口变动产生明显的影响,包括非常规的生育减少、死亡增加和迁移的迟滞。由于疫情传播的严重程度、疫情的疾病负担、疫情传播与控制对社会经济的影响程度、民众的健康风险认知以及受疫情影响的持续时间不同,一些国家的出生人口出现了模式不同的波动。近年来中国出生人口数的加速下降和波动,是新冠疫情带来的推迟效应与中国出生人口数下降大趋势叠加的结果,未来两年可能有一定数量的补偿性生育,但仍将延续初婚和生育推迟的基本趋势。

中国旅游产业链发展格局演变及空间效应研究

产业链现代化是建设现代化产业体系及助推中国式现代化进程的重要抓手,全面揭示旅游产业链发展现状及其影响因素对于提升旅游产业链现代化水平具有实际意义。该文以2001-2019年中国30个省域为研究对象,构建涵盖旅游供需链、企业链、空间链、价值链的旅游产业链发展水平评价指标体系,利用核密度估计、Dagum基尼系数及其分解、探索性空间数据分析等方法对中国旅游产业链发展的时序演变规律、空间差异特征及空间关联格局进行分析,并运用空间杜宾模型探讨影响中国旅游产业链发展的主要因素及其空间效应。研究发现:(1)中国旅游产业链发展水平呈平稳提升态势,表现出由东部地区向中部、东北及西部地区递减的分布态势。(2)中国旅游产业链发展的总体区域差异呈波动缩小趋势,区域间差异是其主要来源,且东部与西部地区旅游产业链发展的区域间差异最大;东部地区旅游产业链发展的区域内差异最大,西部、东北地区次之,中部地区最小。(3)中国旅游产业链发展具有空间相关性和空间集聚特征,供给、需求、创新、政策等层面因素是影响中国旅游产业链发展的主要因素。其中,旅游资源禀赋、旅游人力资本、互联网、产业融合发展与对外开放水平有利于推进本地区旅游产业链发展,旅游需求总量、旅游需求结构与对外开放水平能通过正向空间溢出效应带动邻近地区旅游产业链发展。

重大突发事件冲击下农业企业组织韧性的触发与塑造

农业企业组织韧性的触发与塑造是持续稳固农业基本盘、破局不确定性困境的重要途径,应以追求韧性诱发与生成的共轭为建设农业强国的价值考量。立足“资源-能力-关系”理论框架,运用定性比较分析方法(fsQCA)探讨农业企业组织韧性的多重触发因素及不同因素组态对农业企业组织韧性的塑造机制。研究表明:财务资源、政府补助、企业创新能力、员工薪酬激励和企业社会责任无法单独触发农业企业组织韧性;资源-关系双驱动型、资源-能力-关系共创型及能力-关系协同型是农业企业组织韧性塑造的三种构型。在重大突发事件冲击下,农业企业应“刚柔并济”落实激励机制与风险共担机制,以“人和”为底层逻辑、专项支持政策为破局基石健全保障机制,助推企业逆势成长。

开挖宽度对异形基坑L形转角区支护结构变形影响研究

为研究不同开挖宽度对基坑L形转角区支护结构变形规律的影响,基于滨州市某异形深基坑工程项目的现场实测数据,分析了基坑开挖过程中L形转角区阴阳角位置处支护结构变形规律的差异性;建立了不同基坑宽深比(B/H,B和H分别为基坑宽度和深度)的L形转角基坑模型,研究了不同宽深比条件下转角位置处阴阳角相互作用条件下支护桩水平变形的空间分布规律,进一步明确基坑L形转角区支护桩不同深度处水平变形受影响范围。结果表明:当B/H<1.0时,阳角侧支护桩浅部水平变形受转角效应影响的范围随B/H的增加呈现出明显减小的趋势,其值近似满足2.4H-B;当B/H>1.0时,阳角侧支护桩浅部水平变形受转角效应影响的范围约为1.5H;坑内底部支护桩水平变形受基坑宽深比影响不明显,受转角效应影响的范围约为0.6H;当B/H<1.0时阴角侧支护桩浅部水平变形受影响范围约为1.6H,当B/H>1.0时其水平变形受影响范围约为0.6H+B;坑内开挖底面位置处阴角侧支护桩水平变形受影响范围约为0.6H+B,受宽深比变化影响不明显。

高校英语思辨能力培养模式构建及反拨效应探析

高校英语教育中思辨能力的培养是中国高等教育的核心目标之一,评价标准、测试体系等因素影响着高校英语教育思辨能力的培养。培养语言技能和思辨能力俱佳的英语人才,必须从英语教育管理层面、教师层面和学生层面等不同环节入手,以全方位、多维度地培养学生的思辨能力。思辨能力必然对师生的语言交际能力产生一定的反拨效应,重视培养大学生的思辨能力是培养复合型外语人才的必由之路。

促进各民族交往交流交融有形有感有效——读《图案与仪式:融合发展中的云南多民族文化》

时空意识是各民族文化和精神的基本符号,要理解一个民族的文化,首先要从时空观念入手;而一个民族的时空观念往往与其民族的图案或各种仪式展演有关。《图案与仪式:融合发展中的云南多民族文化》正是从云南各少数民族的时空意识入手,通过自己的“看”与“听”精心绘制了各民族共同筑就的“七彩云南”的空间之美。

基于混合用地模式识别的济南市老城区典型片区绿色空间降温效应分析

城市绿色空间可以通过生态系统服务调节功能有效缓解城市热岛效应,降低高温健康胁迫风险。城市中心城区特别是老城区建成环境具有高度异质性,复杂建成环境中绿色空间的降温效应,特别是混合用地模式中绿色空间的降温强度、阈值、形状等还需进一步明晰。在厘清城市热环境影响因素和绿色空间降温机制基础上,构建了“冷热岛分析提取-混合用地模式聚类识别-混合用地模式热效应分析-典型绿色空间降温效应分析”的研究框架。针对当前城市绿地指标失实、结构失衡、功能失调等现实问题,选择济南市老城区典型片区进行实证研究,重点分析了中层建筑混合用地模式中绿色空间的降温强度、降温面积阈值、形状及植被覆盖度等,总结了具有高降温效能的绿色空间模式,为促进城市健康人居环境发展提供借鉴。

隧道斜向超前系统锚杆支护效果及承载规律

为研究渝昆高铁斜向超前系统锚杆支护体系的力学特性,在乐业隧道开展了斜向超前系统锚杆现场试验,结合有限差分数值模拟,基于支护应力场的概念,实现斜向超前系统锚杆有效支护范围的定量描述,采用多指标(隧道位移差、围岩塑性区、围岩最小主应力)对斜向超前系统锚杆的支护效果进行定量评价。通过分析锚杆轴力、钢拱架轴力的分布特征,确定斜向超前支护体系的承载规律,并与现场试验结果进行验证和对比分析。结果表明:1)隧道开挖后,锚杆支护会形成支护应力场,即在开挖面附近形成了最大主应力增大区,而最大主应力的增大提高了岩体抵抗变形的能力;2)随着掌子面空间效应的减弱,斜向锚杆需要承担的围岩荷载逐渐增大,其有效支护的范围也逐渐增大;3)在掌子面附近,斜向锚杆支护提高了围岩的自承载能力,降低了拱顶、拱肩和拱腰处钢拱架的轴力,改善了钢拱架的受力特征。

导流洞复合式出口消能体型的研究与应用

狭窄河谷中高水头、大流量、复杂地质条件的工程前期导流工程面临高速水流泄洪问题,对消能体型要求较高。基于水工物理模型试验对某水利枢纽导流洞出口消能体型进行优化探索,先后提出右岸导向、洞线偏移、左岸分流、强迫消能+左岸分流4种布置方案,通过对水流流态、流速和冲刷特性等水力参数进行测定和比选,最终推荐强迫消能+左岸分流的复合式消能体型,并对推荐体型对大小流量工况的适应性进行导流全过程试验分析。结果表明:复合式消能体型在各工况下消能效率较高,围堰及左岸近岸流速明显降低,分散水流能有效封堵回流,水面波动强度减弱,主流顺利归槽,冲淤情况良好,保护左岸免受冲刷。该复合式消能体型能够满足工程消能及安全稳定要求,可为具有类似特点的导流洞工程的出口设计提供参考。