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龚胜生  于颖 《地理研究》2006,25(6):1096-1106
历史人口迁移是历史时期区域人地关系演变的最直接的动力。通过对1211375年间湘阴县外来氏族移民过程与空间分布的分析,发现:他们无论是直接迁入还是辗转迁入,绝大多数都是为了土地和生存而来;67.2%的氏族祖籍江西,地缘上的亲和力和血缘上的凝聚力导致了氏族移民迁出地的邻近性和入居地的集聚性;69.6%的外来氏族在明代迁入,后唐同光年间,元末明初,明末清初为三个氏族移民高峰期;不同时期有着不同的氏族移民来源地,不同时期的氏族移民入居到不同的地理空间。随着时间的推移,湘阴县氏族移民入居地从丘陵平原向河湖滩地拓展的演变,反映了湘阴县域乃至整个洞庭湖区从丘陵到平原再到湖区的区域开发过程。  相似文献   
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ABSTRACT. Transplanting pilgrimage traditions, or the process of remaking the collective self in sacred places, requires new sacred places as worthy destinations. As people migrate from the lands where sacred places developed to those where such places may become only a distant memory, many communities attempt to recover their pilgrimage tradition by co‐opting sacred sites of host communities, maintaining links to their homeland, or re‐creating sacred sites in the lands of resettlement through replication, (re)recognition, creating movable rituals, celebrating sites of sacred embodiment, and ritual historicizing. Examples taken primarily from Catholic and Hindu experiences in the Western Hemisphere illustrate this preliminary typology. Transplanting pilgrimage traditions may be viewed as anchoring our individual, existential quests to fleeting ships of “collective selfhood.”  相似文献   
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对对流占优的三维溶质运移问题提出了分步广义迎风解法,首先利用N.N.Ya-nenko对水动力弥散方程分步求解的思想,将原来的一个定解问题分解为两个定解问题即对流定解问题和扩散定解问题,对对流定解问题采用广义迎风对偶单元均衡法求解,对扩散定解问题采用一般的Galerkin有限元法求解,不仅避免了用一般有限元法和有限差分法求解对流占优的地下水水质数学模型时常出现数值弥散和过量问题,而且避免了求节点速度这一步,节省运算步骤,对井点的浓度变化给出了更合适的求解方法。  相似文献   
5.
J. S. Mani 《Natural Hazards》2004,31(2):523-536
Chennai coast, right from the inception of Madras harbourin the year 1876, has been experiencinghostile conditions such as (i) coastal erosion, (ii) sandbar formation at the entrance to inlets, (iii) sea water ingression and (iv) change insea bed elevation, etc. In addition, construction of a new satellite harbour, about18 km north of Madras harbour has produced a negative impact on the delicatecoastal features such as (i) Pulicat lake, (ii) Ennore shoals, etc. Construction ofthis satellite harbour has led to the accumulation of sand south of the southbreakwater of the harbour and its accelerated growth is of concern to an inletlocated 2.6~km south of the harbour. `Coastal erosion', a perennial problemassociated with north Chennai sea front for the past 100 years has been addressedin this paper. The paper discusses on a long term solution and details of themethodologies to be adopted for effective management of the coast. Thesolution presented in this paper is based on numerical model study consideringthe nearshore currents and wave induced sediment transports.  相似文献   
6.
The Last Picture Show does not fall within the genre of the Western, yet the cinematic narrative mourns the loss of the iconic Westerner — a man — and the passing of his home places that constitute the Old West. This paper is concerned with the ways in which this man and his places are transformed along with the embryonic but inexorable emergence of the New West — and its attendant demand for recognition of hitherto unheard voices (e.g., women, Latinos) — that accompanied significant social, cultural and political shifts that were beginning to emerge within the country as a whole in the represented early 1950s. His represented sites of contestation are found within the frame of the small west Texas town of Anarene, created by Larry McMurtry's novel of the same name as the film, both of which reflect contexts of the era in which they were constructed — the mid 1960s to early 1970s. We suggest that the film shows a great sensitivity to the ways in which particular masculinities are constituted in specific places, to the tensions that arise from the changing nature and definitions of masculinity as they are linked to these places, and with his sense of nostalgia and loss that accompanies his inevitable decline. But there is no clear and empowered place for women in these new places, only a recontextualized form of a patriarchal order which is not relational and which still maintains essentialist assumptions of gender. The Old West has taken new shape, much to the chagrin of man, but it is hardly a New West, with its emerging and representative voices. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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台风“尤特”登陆后复杂路径的环境场特征   总被引:1,自引:0,他引:1  
台风"尤特"(1311)2013年8月13—19日登陆减弱后直达桂东北并停留打转,其后又转向西南移动,"尤特"残涡在广西境内生存活动了112 h,造成了大范围强降雨。使用常规与非常规观测资料,研究了"尤特"登陆后的环境场与其长生命期及复杂移动路径的关系。结果发现:"尤特"登陆北上阶段主要受大尺度环境场的引导气流主导,后因引导气流转向减弱,与变压梯度力近似达到平衡导致停留打转;南下弱冷空气卷入与西南气流辐合形成负变压槽,负变压槽中风向气旋性切变产生正涡度效应向"尤特"残涡输送,与西南气流充沛的水汽输送共同作用使"尤特"残涡得以长时间维持。弱冷空气卷入使中尺度变压场中的正变压加强,在变压梯度力与引导气流共同作用下,"尤特"残涡沿负变压槽向西南移动。  相似文献   
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以城市体系与水系的分形结构相似性为实例,探讨人文地理系统与自然地理系统的对称性及其破缺特征。首先建立城市人口—河流长度、城区面积—流域面积、 (某一级别的 )城市数目— (某一等级的 )河流数目等测度对应关系 ;然后证明基于中心地理论的Beckmann城镇等级—规模模型与 Horton水系构成第一、第二定律数理同构,关于城市人口—城区面积的异速生长关系模型与关于主河道长度—流域面积的几何测度关系模型以及 Horton水系构成的第二、第三定律数理同构 ;进而提出 :城市体系与水系分形结构的相似性实质上是自然—人文地理系统的对称性,只是这种对称关系存在一定程度的破缺,地理系统的演化目标之一似乎是要重建大自然的对称律。  相似文献   
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ABSTRACT

This paper presents a brief overview of the geospatial technologies developed and applied in Chang’e-3 and Chang’e-4 lunar rover missions. Photogrammetric mapping techniques were used to produce topographic products of the landing site with meter level resolution using orbital images before landing, and to produce centimeter-resolution topographic products in near real-time after landing. Visual positioning techniques were used to determine the locations of the two landers using descent images and orbital basemaps immediately after landing. During surface operations, visual-positioning-based rover localization was performed routinely at each waypoint using Navcam images. The topographic analysis and rover localization results directly supported waypoint-to-waypoint path planning, science target selection and scientific investigations. A GIS-based digital cartography system was also developed to support rover teleoperation.  相似文献   
10.
近31年登陆北上台风特征及其成因分析   总被引:1,自引:6,他引:1  
金荣花  高拴柱  顾华  刘震坤 《气象》2006,32(7):33-39
为探讨对我国产生严重影响的登陆北上台风的成因,利用1975—2005年台风资料及NCEP/NCAR逐日再分析等资料,分析了登陆北上台风的气候特征及其大尺度环流和物理量分布特征。结果发现,不仅西北太平洋副热带高压位置和强度变化对台风登陆北上起决定性作用,而且西风带系统和南亚高压活动有利于台风登陆后北折和持续北上也有不可忽视的影响。总结归纳台风登陆北上的预报着眼点,希望有助于提高此类台风的预报预警能力。  相似文献   
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