Synthesized Poisson and renewal model and its application in seismic hazard analysis

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ArcObjects在昆山土地利用更新调查中的应用

ArcObjects是形成ArcGIS的基础，是具有GIS功能和可编程接口的软件组件集合。昆山土地利用更新调查的数据处理和建库过程中，通过ArcObjects的底层GIS功能，为数据处理的正确性和高效性提供了保证。     

知识经济与中国城市更新

知识经济是人类社会发展的最新阶段，新的经济形态必将对我国的城市发展和城市更新起到深远的影响。我国目前仍处于工业化进程的中期阶段，但知识经济的影响已经不容忽视。为了我国城市在未来更能适应知识经济的要求，作者对我国现阶段的城市更新提出了若干建议。     

Sensitivity of seismic hazard evaluations to uncertainties determined from seismic source characterization

The sensitivity and overall uncertainty in peak ground acceleration (PGA)estimates have been calculated for the city of Tabriz, northwestern Iran byusing a specific randomized blocks design. Eight seismic hazard models andparameters with randomly selected uncertainties at two levels have beenconsidered and then a linear model between predicted PGA at a givenprobability level and the uncertainties has been performed. The inputmodels and parameters are those related to the attenuation, magnituderupture-length and recurrence relationships with their uncertainties.Application of this procedure to the studied area indicates that effects ofthe simultaneous variation of all eight input models and parameters on thesensitivity of the seismic hazard can be investigated with a decreasingnumber of computations for all possible combinations at a fixed annualprobability. The results show that the choice of a mathematical model ofthe source mechanism, attenuation relationships and the definition ofseismic parameters are most critical in estimating the sensitivity of seismichazard evaluation, in particular at low levels of probability of exceedance.The overall uncertainty in the expected PGA for an annual probability of0.0021 (10% exceedence in 50 yr) is expressed by a coefficient ofvariation (CV) of about 34% at 68% confidence level for a distance ofabout 5km from the field of the major faults. The CV will decrease withincreasing site-source distance and remains constant, CV = 15%, fordistances larger than 15 km. Finally, treating alternative models on theoverall uncertainty are investigated by additional outliers in input decision.     

城市企业社区用地更新潜力分析框架与应用

用地更新潜力分析是践行集约利用空间与城市更新、可持续性城市建设的重要基础,对认识城市土地利用、居住空间转型与治理意义重大,包括面积更新潜力与集约利用潜力。从社区土地面积、空间集约利用和两者关联性3个维度出发,采用企业社区兴趣点、兴趣面数据与建筑基底数据,以及景观格局指数、区位熵、重要性—绩效分析等方法,构建城市企业社区用地更新潜力分析框架,探究用地更新潜力特征,以西安市为案例进行验证。结果表明：① 企业社区总更新潜力933.56 hm²,平均面积1.63 hm²。小型企业社区（0.07~1.18 hm²）居多（62.87%）,面积更新潜力较小（19.42%）,相对集聚于内部市区,桃园路、土门、长乐中路等街道。面积大的数量少,分散在外围市区,洪庆、纺织城、鱼化寨等街道;② 绝大多数企业社区（93.01%）在立体空间上有集约利用潜力,整体呈东西两头稍高、内城中间低的略“U”型分异,以及南部向中北部地区近线性增加趋势;③ 集约利用潜力大的企业社区（A型）占20.63%,平均楼层高度3.31层,以土门、桃园路、纺织城、韩森寨等街道为主。集约利用潜力较大的企业社区（B型）占55.94%,平均5.24层,小集聚、大分散,长乐中路、纺织城、电子城、桃园路等街道分布多;④ 面积更新潜力与集约利用潜力大的高—高型企业社区占13.46%（77个）,主要在中心城区外围,纺织城、电子城、枣园、韩森寨等街道;面积更新潜力小集约利用潜力大的低—高型企业社区占30.07%（172个）,土门、纺织城、桃园路、电子城等街道为主;需要重点关注高—高型和低—高型企业社区更新改造与未来发展建设。应用过程与分析框架匹配,结果与现实较吻合,体现方法架构的逻辑性。研究有助于深化内城居住空间演替理论、新城市主义与城市更新理论。     

卫星遥感影像与航空遥感影像的对比分析

本文对卫星遥感和航空遥感进行对比,并选取同一区域同时期同一比例尺的卫星遥感影像和航空遥感影像的DOM,进行土地利用地类的判译识别,通过对比分析,探讨了利用高精度卫星遥感影像进行土地利用更新的可行性。     

城市更新对房地产市场的时空影响效应:基于杭州市的实证研究

以杭州市为例,采用双重差分法研究城市更新对房地产市场的时空影响效应。研究结果发现： 城市更新在不同阶段对周边住宅价格产生的影响效应不同,项目建设和运营期分别对周边房价产生28.6%和32.0%的推升作用; 城市更新对周边住房价格的影响在空间上存在显著差异,对城市边缘区的提升作用比核心区高23.0%; 城市更新对周边房价影响随着距离增加显著降低,距离城市更新项目中心2.0 km以内、2.0~3.5 km范围对房价的推升作用分别为41.9%、24.9%和9.1%。最后建议政府完善房地产市场微观调控,建立完善长效机制。     

城市基础空间数据基准的统一和更新

对城市基础地理信息数据库的数据源——空间位置数据的基准统一和更新方法进行了探讨,提出七参数转换和平面相似变换是实现空间位置数据的基准统一和更新的实用方法,并通过算例证明了该方法的正确性。     

Earthquake Hazard in Italy, 2001–2030

The study computes time-dependant earthquake probabilities on the basis of seismicity data mainly deriving from historic records. It provides a methodological approach useful for those countries where the scarcity of instrumental data and/or paleoseismological evidences requires that historical information shall be stressed. Thus, the conditional probability that damaging earthquakes (M ≥ 6) may occur in Italy in the next 30 years is shown, and the potential for the main worldwide known Italian cities with a cultural heritage is outlined. Earthquake probabilities are computed referring to the application of renewal processes, where the periodicity is analytically modelled by means of the Brownian Passage Time function; an estimate of the dispersion (i.e., uncertainty) introduced on probabilities is provided making use of Monte Carlo simulations. The computed probabilities refer to seismic source zones deriving from the spatial clustering of the historically documented seismicity. The computation of probabilities based on the interaction of earthquakes occurring in nearby zones, has been also attempted for a test area to explore the influence exerted by the stress transfer effect. The main findings of this study are that (1) seismic source zones in Southern Italy are the most prone to experience damaging earthquakes in the next 30-years, with conditional probabilities a large as 10%; and (2) the influence exerted by the earthquake interaction in increasing such probabilities, doesn’t seem to be relevant, because the mean recurrence times of large earthquakes (above the threshold magnitude of six chosen in this study) are in general much longer than the time shortening produced by the stress transfer.     

Stochastic characteristics of sedimentation in evaporite basins: Potassium strata of Solikamsk deposit

The mode of alternation of halopelite, rock salt, and sylvinite beds in the Solikamsk deposit may be expressed in terms of Markov chains where each state is the lithologic composition of the bed. Both ² and likelihood tests confirm the similarity of the Markov model with the actual geologic sections and suggest that evaporite sedimentation can be modeled by a renewal process.