Mapping fine‐scale urban housing prices by fusing remotely sensed imagery and social media data

The accurate mapping of urban housing prices at a fine scale is essential to policymaking and urban studies, such as adjusting economic factors and determining reasonable levels of residential subsidies. Previous studies focus mainly on housing price analysis at a macro scale, without fine‐scale study due to a lack of available data and effective models. By integrating a convolutional neural network for united mining (UMCNN) and random forest (RF), this study proposes an effective deep‐learning‐based framework for fusing multi‐source geospatial data, including high spatial resolution (HSR) remotely sensed imagery and several types of social media data, and maps urban housing prices at a very fine scale. With the collected housing price data from China's biggest online real estate market, we produced the spatial distribution of housing prices at a spatial resolution of 5 m in Shenzhen, China. By comparing with eight other multi‐source data mining techniques, the UMCNN obtained the highest housing price simulation accuracy (Pearson R = 0.922, OA = 85.82%). The results also demonstrated a complex spatial heterogeneity inside Shenzhen's housing price distribution. In future studies, we will work continuously on housing price policymaking and residential issues by including additional sources of spatial data.     

库车坳陷大北地区下白垩统巴什基奇克组储层成因地质分挝

塔里木盆地库车坳陷大北地区白垩系巴什基奇克组储层以细一中粒岩屑砂岩为主夹少量长石岩屑砂岩,杂基为铁泥质和泥质(2%～10%).胶结物以方解石(3%～15%)为主.粘土矿物以伊利石、绿泥石和伊/蒙混层为主,不含高岭石,伊/蒙混层中的蒙皂石含量一般为(15～20)%;主要孔隙组合为残余原生粒问孔-溶蚀孔-微孔隙,占储集空间总量的(50～90)%,其次为构造缝-溶蚀孔,主要的孔隙类型为溶蚀孔和裂缝,总体属于低孔低渗-特低孔特低渗储层.综合分析认为:阶段性的前陆构造逆冲推覆作用对沉积旋回性、水体盐度变化及物源区距离变化的控制至关重要;构造活跃期扇三角洲前缘环境中形成的差分选中-粗砂岩、近源快速堆积造成的高岩屑含量、干旱成湖导致的高碳酸盐胶结和早成岩期相对深埋-后期持续快速深埋压实作用,是特低孔特低渗储层的主要成因;而较优质储层足构造平缓期辫状河三角洲前缘环境中形成的分选好的中-细砂岩、早期表生溶蚀及弱碳酸盐胶结作用、早期构造破裂的复合作用及其叠加效应的结果.     

中国东部新生代玄武岩及其地幔包体的氧逸度

地幔环境的氧逸度与温度和压力一样,是控制许多地幔过程的一个重要参数。本文计算了中国东部几个具有代表性地区的玄武岩和尖晶石二辉橄榄岩的氧逸度,尖晶石二辉橄榄岩的氧逸度变化不大,均位于１ｏｇ（ｆｏ２）＝ｌｏｇ（ｆｏ２ＦＭＱ）＋０．０左右,而各地区玄武岩的氧逸度却变化很大,其平均值从尚志地区的ｌｏｇ（ｆｏ２ＦＭＱ＋０．６到长白山地区的ｌｏｇ（ｆｏ２ＦＭＱ）＋３．３左右（其中东北地区钾质玄武岩的氧逸度比除尚志以外其它地区的低）,并且总体具有比地幔橄榄岩高得多的氧逸度。推测钾质玄武岩和尚志地区破性玄武岩的氧逸度比中国东部其它地区玄武岩的氧逸度低的可能原因是,前二个地区的玄武岩来源于更深部的（金云母）石榴石二辉橄榄岩,而其它地区的玄武岩来源于略浅部的尖晶石二辉橄榄岩。     

Fracture plane control in rock blasting

ＩＮＴＲＯＤＵＣＴＩＯＮＴｕｎｎｅｌｅｘｃａｖａｔｉｏｎｂｙｂｌａｓｔｉｎｇｍｅｔｈｏｄｉｎｈａｒｄｒｏｃｋｉｓｕｓｕａｌｙａｃｃｏｍｐｌｉｓｈｅｄｗｉｔｈａｄｒｉｌａｎｄｂｌａｓｔｐｒｏｃｅｄｕｒｅｗｈｅｒｅａｂｏｒｅｈｏｌｅｉｓｄｒｉｌｅｄｉｎｔ...     

地下水对工程和环境的作用

地下水对上程建设和地质环境的作用与影响日趋显著,人们认识日益深化。实践表明,这类问题不完伞是纯水文地质问题。实质上,它是介乎于水文地质与工程地质之间,暂定名为工程水文地质学。专门进行在工程建设和环境地质中由于地下水作用而产生的各类工程地质问题或水文地质问题。为充分阐明问题,本文从水与岩土相互作用、基坑排水与潜蚀流沙、地基沉降与黄土湿陷、道路冻害与隧道涌水、矿抗突水与竖井破坏、坝基渗漏与稳定、坝基抗滑稳定以及与地下水有关的地质灾害问题等方面,进行了举例阐述,初步论证了重要性、问题和某些实质。目的在于,向人们揭示一个值得研究的方向,并给予充分的重视。     

Energy flux partitioning and evapotranspiration in a sub‐alpine spruce forest ecosystem

In this study, we examined the year 2011 characteristics of energy flux partitioning and evapotranspiration of a sub‐alpine spruce forest underlain by permafrost on the Qinghai–Tibet Plateau (QPT). Energy balance closure on a half‐hourly basis was H + λE = 0.81 × (R_n ? G ? S) + 3.48 (W m^?2) (r² = 0.83, n = 14938), where H, λE, R_n, G and S are the sensible heat, latent heat, net radiation, soil heat and air‐column heat storage fluxes, respectively. Maximum H was higher than maximum λE, and H dominated the energy budget at midday during the whole year, even in summer time. However, the rainfall events significantly affected energy flux partitioning and evapotranspiration. The mean value of evaporative fraction (Λ = λE/(λE + H)) during the growth period on zero precipitation days and non‐zero precipitation days was 0.40 and 0.61, respectively. The mean daily evapotranspiration of this sub‐alpine forest during summer time was 2.56 mm day^?1. The annual evapotranspiration and sublimation was 417 ± 8 mm year^?1, which was very similar to the annual precipitation of 428 mm. Sublimation accounted for 7.1% (30 ± 2 mm year^?1) of annual evapotranspiration and sublimation, indicating that the sublimation is not negligible in the annual water balance in sub‐alpine forests on the QPT. The low values of the Priestley–Taylor coefficient (α) and the very low value of the decoupling coefficient (Ω) during most of the growing season suggested low soil water content and conservative water loss in this sub‐alpine forest. Copyright © 2013 John Wiley & Sons, Ltd.     

地磁匹配特征量的选择

论文旨在选择合适的地磁特征量用于匹配制导.从地磁匹配的实际要求出发,提出了选择匹配特征量时应重点考虑的几个因素,通过理论分析初步拟定了选取准则,并针对特定区域,依据IGRF(International Geomagnetic Reference Field)和WMM(World Magnetic Model)计算出的地磁数据,结合选取准则进行了综合分析,给出了初选结果,对地磁匹配基准图的制备、实时图的获取、匹配算法的研究,以及地磁场资源应用于其他领域的相关研究有一定的借鉴意义.     

六安地区BBVS-60与KS-2000宽带地震计系统性能分析

通过对六安地区BBVS-60与KS-2000地震计系统记录台基噪声功率谱密度计算,和正弦标定数据处理,尤其通过对仪器系统记录地震震相分析,比较两种类型宽频带地震计系统的性能差异,为台站地震记录震相分析与仪器维护提供技术支持.     

塔里木河下游退化荒漠河岸林地上植被与土壤种子库关系初探

以塔里木河下游为研究区,选择退化程度不同的4个典型断面19个样地,利用种子萌发法进行了两年的种子库土壤萌发实验,试图就生态严重退化区的土壤种子库与地上植被的关系以及退化程度的差异对种子库特征的影响开展针对性的研究。结果显示: ①塔里木河下游土壤种子库的基本特征是:种子库密度小、物种种类组成较单一、物种的多样性低和地上植被与种子库的相似性较低;②随退化程度的加剧,土壤种子库密度明显下降、表层种子库比例升高、一年生草本占优势逐渐向多年生草本和灌木转变、地上植被与土壤种子库物种组成上差异显著;③退化过程中种子库多样性的变化比地上植被变化要迟缓,但是在植被退化演替的末期,土壤种子库的物种多样性指数衰减的幅度又明显快于地上植被的衰减幅度;④受干旱环境和严重退化的双重影响塔里木河下游土壤种子库与地上植被的关系表现出退化演替末期共有物种数的减少和相似性明显递减的特点。