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941.
网络地图人性化界面设计   总被引:10,自引:0,他引:10  
郑束蕾  陈毓芬 《测绘学院学报》2005,22(4):300-303,306
目前网络地图发展迅猛,但界面设计缺少理论指导,仍存在着许多问题.文中首先研究了网络地图的特点和界面内容,对目前网络地图界面设计中存在的突出问题进行归纳.接着提出了基于认知心理学理论的一般性网络地图界面设计原则.最后,对网络地图的用户层次进行分类,举例说明上述设计原则在人性化网络地图界面设计中的应用.  相似文献   
942.
As the Mississippi River plays a major role in fulfilling various water demands in North America, accurate prediction of river flow and sediment transport in the basin is crucial for undertaking both short‐term emergency measures and long‐term management efforts. To this effect, the present study investigates the predictability of river flow and suspended sediment transport in the basin. As most of the existing approaches that link water discharge, suspended sediment concentration and suspended sediment load possess certain limitations (absence of consensus on linkages), this study employs an approach that presents predictions of a variable based on history of the variable alone. The approach, based on non‐linear determinism, involves: (1) reconstruction of single‐dimensional series in multi‐dimensional phase‐space for representing the underlying dynamics; and (2) use of the local approximation technique for prediction. For implementation, river flow and suspended sediment transport variables observed at the St. Louis (Missouri) station are studied. Specifically, daily water discharge, suspended sediment concentration and suspended sediment load data are analysed for their predictability and range, by making predictions from one day to ten days ahead. The results lead to the following conclusions: (1) extremely good one‐day ahead predictions are possible for all the series; (2) prediction accuracy decreases with increasing lead time for all the series, but the decrease is much more significant for suspended sediment concentration and suspended sediment load; and (3) the number of mechanisms dominantly governing the dynamics is three for each of the series. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
943.
1 Introduction Chevkinite groups can be assigned to the chevkinite-(Ce) subgroup and perrierite-(Ce) subgroup in accord with the angle β : β ≈ 100o for the chevkinite subgroup and β ≈ 113o for the perrierite subgroup. Chevkinite-(Ce), polykovite-(Ce) and Maoniupingite (new mineral No. 017 of 2003) belong to the former subgroup, while renjeite and matsubaraite belong to the latter group. As strontio-chevkinite is a Sr-analogue of perrierite, usually the natural chevkinite-(Ce) group min…  相似文献   
944.
国外空间规划特点及其对我国的借鉴   总被引:1,自引:0,他引:1  
空间规划是社会经济、社会文化和生态政策的地理表达,因此受地域、历史文化、法律、政体的影响很大,各国的空间规划体系形成了各自的特点。本文首先有着悠久规划历史的英、美、日、德、法和欧盟的空间规划的特征及发展趋势进行了分析比较,在此基础上,剖析了我国空间规划存在的问题,指出国外空间规划经验对我国空间规划借鉴的七个方面。  相似文献   
945.
邹松柏  张剑清  刘会安 《测绘工程》2006,15(2):50-52,69
航空摄影测量内外业一体化成图过程中,如果采用单像加DEM的方法对数字判绘成果进行纠正,在地形起伏较大的复杂地貌区域遇到了很多的问题,当DEM存在较大误差时得到的纠正成果精度不好。阐述了单像加DEM进行纠正的原理,并对成果的误差进行了分析。介绍了双像立体后交—前交解求空间坐标的方法,并对双像立体与单像加DEM两种成图方法进行比较。  相似文献   
946.
947.
Ivan J. Townshend 《GeoJournal》2006,66(1-2):103-120
The privatization of urban space, as represented in the trend towards a wide variety of common interest developments and increasing prevalence of gated communities, is an international phenomenon. Recent research has not systematically explored the ways in which these types of developments are collectively re-shaping the public and private realms of the city at large. This empirical study of community areas in a Canadian city describes a number of historical private neighbourhood development trends and their convergence in space and time. Based on the empirical generalizations, a conceptual model is developed to illustrate how the trends may have combined to produce a new geography or ecology of space privatization within the city, one in which the older public city is being circumscribed and bounded by new territories of multi-tiered privatization.  相似文献   
948.
In the course of the last 50 years, the landscape in Israel has undergone major changes, due to accelerated urbanization following population growth. These processes had increased the pressure on the open land, especially in areas of urban expansion. Recognizing that Governments and local Municipalities had failed to stop the consequent loss of public open spaces, not only in Israel but worldwide, had lead recently many communities to adopt new solutions in the form of private open spaces. In this article we present a “step ahead of time”: a case of privately owned land, set aside as public green area during the 1920s in a neighborhood called “Ahuza Herbert Samuel” (Herbert Samuel, the first High Commissioner of Palestine under the British Mandate), located in the City of Haifa, in Northern Israel. The roots of this unique phenomenon during the 1920s could be linked to several sources of influence: Colonial town planning concepts, the emergence of garden cities and garden suburbs and most importantly to concepts brought in by the leaders of the immigrant community coming from Rumania. Photogrammetric and GIS analysis of this phenomenon had revealed that it had prevailed throughout 75 years of constant and massive increase in the demand for built-up areas in Israel in general and in Ahuza neighborhood in particular. The success in preserving these open areas gains current relevance in view of recent trends in the Western world of allocating privately owned green areas for public use.  相似文献   
949.
In Korea most of the old mine workings were worked with room and pillar method or sublevel caving method and today they possess great possibility of surface subsidence especially for shallow depth mines. In most of the cases, mine roadways, rooms and pillars are irregular in shape and information about the local geology is uncertain. For these reasons, it is difficult to standardize the estimating method of subsidence especially sinkhole type over abandoned mine area. This paper describes the application procedure for the fuzzy reasoning techniques to analyze the possibility of sinkhole occurrences over abandoned mines. This technique is implemented in software which can simplify the analysis procedure and present the possibility of sinkhole subsidence without having precise information about local geological/mining conditions. This technique has been applied to forecast sinkhole possibilities at Bonghwa site where a massive sinkhole has already been occurred.  相似文献   
950.
一种城市形态中的空间可视分析方法   总被引:4,自引:0,他引:4  
应申  李霖  王红  高玉荣  彭晓艳 《测绘学报》2006,35(4):385-389
空间可视分析是空间句法的重要依据,是进行城市空间形态分析的新方法。在视域的行为指导原理上,采用可视集中性的概念来进行可视分析,进而通过可视分析各参数的具体量化,包括视域面积、视线长度等,将其应用到具体的城市街道形态中,分析各参数量化大小的分布情况。研究城市形态中可视分析通过“视域法则”影响人的行为,从而潜在决定城市内有关行人等基础设施的布局情况,现实中的设施分布也证明了这种分析的正确性。以武汉市中南地区为分析实例,说明上述各过程,验证城市形态对空间设施分布的影响。  相似文献   
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