长三角区域一体化对城市碳排放的影响研究

长三角地区是中国高质量一体化发展的示范区,也是实现“双碳”目标的重要区域。在中国行政区经济向一体化经济转变的背景下,长三角区域一体化政策在降低行政壁垒,优化要素配置的同时,产生了怎样的碳排放效应?本文基于中国地级及以上城市的面板数据,以2010年《长江三角洲地区区域规划》的颁布视作一项准自然实验,运用双重差分（DID）模型,研究长三角区域一体化对城市碳排放的影响。在此基础上,采用中介效应模型,识别区域一体化碳排放效应的内在机理。结果表明：2010 年实施的长三角一体化政策显著降低了城市碳排放,并经过共同趋势检验、PSM-DID、安慰剂检验等稳健性检验依然成立;从动态效应来看,区域一体化政策的碳减排效应出现在政策实施后的第三年;从城市等级来看,区域一体化政策对高等级城市碳排放减少的促进作用大于一般城市;从作用机理来看,区域一体化政策通过促进产业结构的升级和城市技术水平的提高,显著降低了城市碳排放,而通过城市间经济联系的增强,在一定程度上增加了城市碳排放。因此,建议建立长三角城市间碳减排与绿色发展的互动合作机制,构建可监测、可操作的绿色发展评价指标体系,加大长三角城市绿色科技联合攻关力度,推动产业低碳化发展。     

区域一体化的理论概念及其发展

为了明确国际性区域经济合作的理论和实践对中国开展区域经济合作的参照性，本文对国际性区域合作的基本理论概念及其演变进行较为系统的总结和分析。首先阐述了用来描述在国家之间建立区域化、集团化合作关系的基本概念--“区域一体化”的理论内涵，然后概括分析了60年代以来，特别是冷战结束后，世界经济的区域化、集团化发展实践对“区域一体化”概念的传统理论界定的挑战，并对近年来有关世界范围内区域经济合作现象的理论概念的新发展进行了概括总结，在此基础上，提出澄清有关认识的必要性。     

地面点云处理系统集成研究与实现

地面点云数据后处理及软件研制是制约地面三维激光扫描技术进一步发展的关键因素。本文集成Oracle存储、PCL模块点云算法、OpenGL三维显示技术,初步研发了一套集点云存储、处理、显示、查询功能于一体的地面点云处理系统。通过RIEGL VZ-400扫描的雕像测试点云,验证了本文提出的三种技术集成开发地面点云处理系统的可行性和系统功能的稳健性。为进一步研究地面点云数据处理系统提供有益的参考。     

Simple computer code for estimating cosmic-ray shielding by oddly shaped objects

This paper describes computer code for estimating the effect on cosmogenic-nuclide production rates of arbitrarily shaped obstructions that partially or completely attenuate the cosmic ray flux incident on a sample site. This is potentially useful for cosmogenic-nuclide exposure dating of geometrically complex landforms. The code has been validated against analytical formulae applicable to objects with regular geometries. It has not yet been validated against empirical measurements of cosmogenic-nuclide concentrations in samples with the same exposure history but different shielding geometries.     

基于IFC标准的三维地质模型扩展研究

岩土工程信息化迫切需要加强大数据集成共享和多专业协同合作,BIM技术在工程建设领域的成功经验给我们以启示,可将BIM技术应用于岩土工程信息化建设,但是当前存在的主要问题是地质模型与BIM模型数据标准不统一。为了解决这个问题,提出了地质模型采用BIM数据标准IFC的思路。采用IFC实体扩展及属性集扩展模式,建立了面向三维地质模型的扩展模型IFC-3DGeoMdl。利用已有的IFC对象类型,派生相应的地质物理实体以及地质空间结构实体,给出地质物理实体的空间表达形式;利用IFC中已有的关系类,定义地质物理实体与空间结构实体的关系;进而,基于IFC中的属性表达方式,实现了地质对象的地层信息与物理力学参数等属性的扩展;最后,给出了创建该模型的具体实现过程,并利用实例验证了该模型的实际应用效果。结果表明,采用该模型,可有效实现岩土工程地质模型与BIM结构模型的集成,从而为深化岩土工程的结构设计、施工等提供有效的地质模型信息。     

兰州市城关区地理信息集成系统设计与实现

介绍了兰州市城关区地理信息集成系统的设计思路、数据构成、集成方法、关键技术和系统功能。系统的建成进一步提升了社区管理水平和基层工作人员的工作效率,极大地提高了城市管理的信息化水平。     

不动产统一登记的难点与对策—湖南澧县试点的经验总结

自湖南省开展不动产统一登记试点工作以来,澧县不动产统一登记已进入全面实施阶段。该文扼要叙述了澧县不动产统一登记的推进进程,分析了不动产统一登记的难点,并从总结试点经验入手,探析需要把握的组织机构、岗位设置、工作衔接、资料移交等工作要点,提出了湖南全面开展不动产登记工作的建议。     

Ad hoc matching of vectorial road networks

In integration of road maps modeled as road vector data, the main task is matching pairs of objects that represent, in different maps, the same segment of a real-world road. In an ad hoc integration, the matching is done for a specific need and, thus, is performed in real time, where only a limited preprocessing is possible. Usually, ad hoc integration is performed as part of some interaction with a user and, hence, the matching algorithm is required to complete its task in time that is short enough for human users to provide feedback to the application, that is, in no more than a few seconds. Such interaction is typical of services on the World Wide Web and to applications in car-navigation systems or in handheld devices.

Several algorithms were proposed in the past for matching road vector data; however, these algorithms are not efficient enough for ad hoc integration. This article presents algorithms for ad hoc integration of maps in which roads are represented as polylines. The main novelty of these algorithms is in using only the locations of the endpoints of the polylines rather than trying to match whole lines. The efficiency of the algorithms is shown both analytically and experimentally. In particular, these algorithms do not require the existence of a spatial index, and they are more efficient than an alternative approach based on using a grid index. Extensive experiments using various maps of three different cities show that our approach to matching road networks is efficient and accurate (i.e., it provides high recall and precision).

General Terms:Algorithms, Experimentation     

球函数分析中经向数值积分的改进方案

在全球气候场的球函数分析中,定积分∫＾ｎｏｑ（θ）ｓｉｎθｄθ的近似计算是重要的。本文基于几何分析给出了它的一个改进方案,对标准化缔化勒让德函数Ｐ＾ｍ,ｎ的模和正交性计算表明,它可以明显提高气候场球函数分析的精度。     

Practical Symplectic Methods with Time Transformation for the Few-Body Problem

The use of the extended phase space and time transformations for constructing efficient symplectic algorithms for the investigation of long term behavior of hierarchical few-body systems is discussed. Numerical experiments suggest that the time-transformed generalized leap-frog, combined with symplectic correctors, is one of the most efficient methods for such studies. Applications extend from perturbed two-body motion to hierarchical many-body systems with large eccentricities. This revised version was published online in July 2006 with corrections to the Cover Date.