郑州市城市环境建设可持续发展初探

文章通过对郑州市城市环境问题及城市建设发展概况的分析，认为城市发展与环境建设是相辅相成的，并探讨了保证城市环境建设可持续发展的对策，切实做好总体规划，加强水资源管理，注重绿化效果，提高清洁能源的使用率等。     

北京市二手房价格时空演变特征

城市住宅价格时空格局及演变特征是衡量城市房地产市场发展均衡性的重要指标。针对海量的互联网实时房产数据,本文构建了一种长时序时空大数据挖掘方法。首先,利用挂牌数据和成交数据,进行了泛在网络地产数据的可用性验证;其次,提出了“混合像元”的多尺度栅格模型,以构建基于栅格系统的房产统计特征描述,形成了多源网络房产数据融合方法;然后分别采用莫兰指数和地理探测器分析房价的空间自相关性和分异性,并基于P-Bshade和邻近栅格时空插值算法解决了稀疏房产数据的融合与插值问题,构建了长时序房地产时空栅格数据库;最后,以北京六环范围内为研究区域,通过栅格区划算法进行了二手房价格时空演变格局的挖掘分析。     

月球交会对接VLBI差分时延研究

中国探月3期任务中,月球交会对接技术是任务成功的重要保障.利用嫦娥3号(CE03)绕月飞行的VLBI (Very Long Baseline Interferometry)时延数据,模拟仿真绕月交会对接过程中,同波束VLBI观测模式下,差分群时延的变化情况.仿真结果显示,在远程导引段,轨道器和上升组合体轨道距离保持100 km,持续半小时,差分群时延很好地反映了两者的轨道信息,可以用于定轨定位;自主控制段,上升组合体靠近轨道器,在轨道距离从5 km减小到20 m过程中,上升组合体加速追赶轨道器时,差分群时延快速趋近于0,上升组合体减速远离轨道器时,差分群时延绝对值快速变大.最后,利用嫦娥3号奔月段同时发射两个DOR (Differential One-Ranging)信号的VLBI时延数据,计算差分相时延,初步展示了月球交会对接过程中同波束VLBI差分相时延的误差情况.     

流星暴的航天定义

定义ZHR^*以每小时穿过1000平方公里天顶截面的，能在铝质表面打出直径不小于1厘米的弹坑的流星体数，作为流星群对航天安全威胁强度的定量标志，给出了从ZHR到ZHR^*的换算公式．用ZHR^*取代ZHR来评价20世纪90年代以来的一些强流星雨，发现1998年的贾可比尼(天龙座)流星雨对航天安全来说，是比公认的1999、2001、2002年3次狮子座流星暴强数倍的更强流星暴．     

基于DTW与K-means算法的河北场雨及雨型分区特征研究

深入挖掘气象站点的观测降雨数据,研究区域降雨的雨型规律,对于洪涝灾害预警和减灾措施制订有重要意义.本文基于河北省2005-2017年3189个站点逐小时降雨观测数据,进行"场雨"的划定,进而提取历史上各场雨的累积雨量、时长指标.采用数据挖掘技术中的DTW相似性算法进行场雨雨型的自动归类,将场雨分成Ⅰ-Ⅶ共7种雨型,包括...     

全域规划视角城市轨道交通与其他交通方式衔接研究进展

采用文献梳理法对中国知网刊载以城市轨道交通为主题期刊文献进行分析,发现国内研究集中在:(1)轨道交通与常规公交、慢行交通体系、出租车、私家车、大型机场等间的换乘组织与连接规划;(2)城市轨道交通网络内部的换乘与衔接,及轨道交通站点空间组织等领域研究;(3)国内研究聚焦在各式交通方式衔接规划及城市路网为主的硬件建设等,但较少关注各类群体出行行为模式及其对交通方式换乘规划影响等.最后展望了中国大城市进入老龄化社会需要关注的轨道换乘研究方向.     

协同多时相波谱特征的不透水面信息级联提取

不透水面作为反应城市表征变化和区域城镇化的重要技术指标,其位置、图斑大小、空间分布等信息在地表水热循环和能量平衡等领域被广泛需求。传统方法大都基于单一时相信息提取不透水面,而忽略多时相所蕴含的丰富信息。因此,本文提出多时相信息融合的不透水面级联提取方法,利用Landsat-8 OLI遥感影像分析归一化植被指数（Normalized Difference Vegetation Index, NDVI）、改进的归一化水体指数（Modified Normalized Difference Water Index, MNDWI）和归一化建筑指数（Normalized Difference Building Index, NDBI）年内时序变化特点和典型地物间多时相波谱曲线的协同特征,并归纳不透水面多时相变化规律;再根据先验知识所获取的有效地表信息,进行多时相分级提取不透水面信息。此外,基于实地考察数据和同期2 m GF-1遥感影像屏幕数字化生成30 m不透水面图斑,进行精度验证、分析和对比单时相、四季相及多时相3种时序情况下的提取精度。结果表明：单时相提取不透水面总精度最低,四季相提取精度优于单时相,而多时相提取精度最高（精度可达93.66%,Kappa系数为0.81）。本方法在偏远城镇不透水面的有效识别中显露潜在优势,可为不透水面提取方法融合时序波谱特征提供新思路。     

新疆河流年径流量对夏季0C层高度变化的响应

According to climate features and river runoff conditions, Xinjiang could be divided into three research areas: The Altay-Tacheng region, the Tianshan Mountain region and the northern slope of the Kunlun Mountains. Utilizing daily observations from 12 sounding stations and the annual runoff dataset from 34 hydrographical stations in Xinjiang for the period 1960-2002, the variance of the summertime 0℃ level height and the changing trends of river runoff are analyzed both qualitatively and quantitatively, through trend contrast of curves processed by a 5-point smoothing procedure and linear correlation. The variance of the summertime 0℃ level height in Xinjiang correlates well with that of the annual river runoff,especially since the early 1990s, but it differs from region to region, with both the average height of the 0℃ level and runoff quantity significantly increasing over time in the Altay-Tacheng and Tianshan Mountain regions but decreasing on the northern slope of the Kunlun Mountains. The correlation holds for the whole of Xinjiang as well as the three individual regions, with a 0.01 significance level. This indicates that in recent years, climate change in Xinjiang has affected not only the surface layer but also the upper levels of the atmosphere, and this raising and lowering of the summertime 0℃ level has a direct impact on the warming and wetting process in Xinjiang and the amount of river runoff. Warming due to climate change increases the height of the 0℃ level, but also speeds up, ice-snow melting in mountain regions, which in turn increases river runoff, leading to a season of plentiful water instead of the more normal low flow period.     

THERMAL EFFECTS OF BUILDING′S EXTERNAL SURFACES IN CITY——Characteristics of Heat Flux into and out of External Wall Surfaces

1INTRODUCTIONWiththerecentmodernizationandurbanizationofChi-na,urbanareashavegreatlyincreased, andgiantbuild-ings,especiallythosetallerthan100m,havebeendomi-nantincities,whichhave resultedinthegreatincreaseintheproportionofbuilding'sexternalsurfacetototalurbanarea.Thedifferencesofthermalpropertiesmain-lyinducedbysolarradiationbetweenbuilding'sexter-nalsurfacesareobviousfordifferentexposures,whichcaninevitablyinfluencethedistributionsofairtempera-turenearby,eventheverticaldistributionsofurb…     

A discussion on the distribution of international container junction ports in northern China

1 The Raising of the Problem 1.1 The development of the international container traffic At the end of the 1930s, the developed countries began to develop container traffic, following the first one established on land which prevailed marine transport after expansion in the 1970s and the 1980s. Then many junction ports had special container berths constructed throughout the world and all main transportation lines were containerized. With the development of the world trade and increase of the pr…