环首都地区城乡融合水平时空分异及乡村振兴路径

构建适于县域尺度的城乡融合评价指标体系,借助泰尔指数、ESDA方法分析1995—2018年间环首都地区县域尺度城乡融合水平时空分异特征,并划分出城乡融合发展类型区,提出差异化的乡村振兴路径。结果表明：（1）以2000年为拐点,环首都地区县域尺度城乡融合水平经历了先减后增的“U”型变化历程,整体趋势向好;城乡融合水平的区域差距先增后减,总体趋于缩小。北京及环京三市区域间的差异对总体城乡融合水平差异的贡献率略高于两类地区内部差异,环京三市内部差异是造成两类地区内部差异的主要原因;张家口市与保定市内部差异是影响环京三市城乡融合水平总体差异的主要原因,其中保定市内部差异占主导地位。（2）低水平融合区的数量波动减少,高水平融合区持续增加;城乡融合水平高、低值区的“核心—边缘”结构突出,且经历了“单组单核—多组多核—单组多核”的动态演变历程;城乡融合水平呈现显著的空间正相关性,集聚性先增后减;城乡融合热点区呈团簇状集聚在北京市域范围内,冷点区和次冷点区呈环形或带状布局在保定市中心城区外围,状态渐趋温和;城乡融合“冷热”空间格局与地理环境和社会经济发展背景联系紧密。（3）可将环首都地区划分为五类城乡融合区：城乡融合引领示范区、城乡融合先行发展区、城乡融合优化升级区、城乡融合转型提升区和城乡融合落后欠发达区,并根据各类型区特点,提出差异化的乡村振兴实施路径。     

青海省人口规模预测及人口发展对策研究

人口是社会的基础要素,人口规模及发展趋势预测对区域城市规划的制定和人口政策的调整具有重要的参考意义.综合运用灰色、阻滞增长、人口自然增长、回归分析四种数学模型对青海省2013--2030年人口规模及发展趋势进行预测,结果表明：未来青海省总人口将继续处于稳定增长状态,年平均人口增长率8.77‰,2020年青海省年末常住人口将达到621.11万人,2030年将达到676.25万人.针对青海省的省情和人口发展形势提出相应对策和建议.     

分布式光纤测温系统在公路隧道火灾探测中 响应特性研究

随着交通运输的快速发展,公路隧道火灾监测与报警越来越重要。目前分布式光纤测温系统已被广泛应用到隧道火灾的监测中,外界风速和隧道断面对火灾监测有一定的影响。该文通过FDS数值模拟和全尺寸实验模拟不同高度的公路隧道发生火灾时,分布式光纤测温系统的报警响应情况。结果表明：在外界风力作用下,传感器的报警位置发生显著偏移;随着隧道高度的增加,分布式光纤感温火灾探测系统报警响应时间延长,可能会不报警。     

渤海海域超大型船舶安全航速限定标准研究

为确保超大型船舶在渤海海域的航行安全,避免偏航和搁浅事故的发生,鉴于船舶安全航速限定标准的重要性,提出基于交通流要求(纵向)、航道尺度要求(横向)和富裕水深(UKC)要求(垂向)的船舶安全航速三维限定数学模型。研究在渤海海域通航条件下,以超大型油轮(VLCC)和散装船为代表船型的船舶在不同风流条件下的安全航速限定标准。结果表明,不同船舶的安全航速限定标准不同,该标准应考虑风流、航宽、水深等条件,并与船舶方形系数有直接关系。     

The Dual Model for Tourism Resource Productivity Improvement

Abstract

For natural resource science, resource productivity studying is an important subject. But researches on tourism resource productivity are limited. The most significant influencing factor on tourism resource productivity is the potential market scale of tourist locations, and second most important influencing factor is the resource endowment. Regional urban population is significantly correlated with region tourist numbers, being the decisive factor of region potential tour market scale. In tourism development, the dual model should be adopted: on one hand to enhance tour spot attractiveness, on the other hand to cultivate the potential market by improving urbanization level and other means. In the situation of tourism development fever spreading, the dual model for improving tourism productivity helps to avoid the “Great Leap Forward” which means that too rapid tourism construction divorces from actual market demand.     

绿洲规模扩张的资源环境与生态阈限

本文系统分析了绿洲规模扩张的资源、环境与生态阈限。干旱区绿洲规模的扩张在总体上要受到资源、环境与生态阈限的制约。在绿洲经济发展过程中 ,无视这些阈限的制约 ,就会出现绿洲规模扩张的无度化 ,并产生一系列环境、生态问题 ,导致绿洲人地关系的极度失调。因此 ,要摒弃绿洲可无限扩张的认识。绿洲规模调控或绿洲适度规模的研究 ,应以这些阈限为理论基础 ,绿洲可持续发展在客观上也需要对这些阈限的深刻揭示。     

Dynamics of species and species complexes as a field of research in historical ecology

Specific features of research on the dynamics of species and species complexes are considered on the basis of data on Late Cenozoic subfossil and fossil bone remains. Special attention is given to the objects to be reconstructed, the principles of their classification, and the concept concerning three scales of these dynamics: the actual, historical, and evolutionary scales. Published in Russian in Ekologiya, 2006, No. 6, pp. 452–456. The text was submitted by the author in English.     

地铁十字换乘车站全尺寸实验研究:Ⅱ.站台火灾

为了解在不同通风模式下地铁十字换乘车站站台火灾发展规律,通过在地铁十字换乘车站站台开展全尺寸火灾实验,分析了不同通风模式下站台层火灾的烟气扩散速率、沉降高度和扩散范围。研究结果表明:该类型车站站台火灾烟气扩散受到建筑结构和通风条件等因素的影响;在A线路站台层发生火灾时,站台断面面积沿烟气扩散方向的缩小有效抑制了烟气向远端扩散;站台机械通风能够有效降低烟气扩散速率,控制烟气扩散区域和沉降高度;在0.5 MW火灾规模下,A线路站台火灾对B线路影响不明显。     

SWAT‐LUT: A Desktop Graphical User Interface for Updating Land Use in SWAT

Long‐term simulations of agricultural watersheds have often been done assuming constant land use over time, but this is not a realistic assumption for many agricultural regions. This paper presents the soil and water assessment tool (SWAT)‐Landuse Update Tool (LUT), a standalone, user‐friendly desktop‐based tool for updating land use in the SWAT model that allows users to process multi‐year land use data. SWAT‐LUT is compatible with several SWAT model interfaces, provides users with several options to easily prepare and incorporate land use changes (LUCs) over a simulation period, and allows users to incorporate past or emerging land use categories. Incorporation of LUCs is expected to provide realistic model parameterization and scenario simulations. SWAT‐LUT is a public domain interface written in Python programming language. Two applications at the Fort Cobb Reservoir Experimental Watershed located in Oklahoma and pertinent results are provided to demonstrate its use. Incorporating LUCs related to implementation of recommended conservation practices over the years reduced discharge, evapotranspiration, sediment, total nitrogen, and total phosphorus loads by 59%, 9%, 68%, 53%, and 88%, respectively. The user’s manual is included in this article as Supporting Information. The SWAT‐LUT executable file and an example SWAT project with three land use rasters and the user’s manual are available at the United States Department of Agriculture‐Agricultural Research Service Grazinglands Research Laboratory website under Software. Editor’s note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series.