Report on Cartographic and GIS Activity in the U.S. Fish and Wildlife Service

The U.S. Fish and Wildlife Service (FWS) is a federal agency whose mission is, working with others, to conserve fish and wildlife and their habitats for the continuing benefit of the American people. Under the management of fish and wildlife professionals, the National Wildlife Refuge System has become the world's premier network of wildlife habitats. The FWS is making use of modern cartographic methods and implementing Geographic Information Systems to more effectively manage the lands and resources entrusted to them.     

Integrating Sketch Maps with GIS to Explore Fear of Crime in the Urban Environment: A Review of the Past and Prospects for the Future

Understanding the spatial dimension of fear of crime in the urban environment is important to understanding behaviors in response to this concern. Making this connection between perception and action has long been a goal of scholars in the social and health sciences, though this complex relationship has yet to be fully elucidated. Specifically, in studies on fear of crime and its influence on behavior, a variety of definitions and methods have been employed. This situation has yielded insights, as well as inconsistencies. In the past decade, Geographic Information Systems (GIS) has been added to this methodological mix, though it too has contributed limited understanding of the environmental perception-behavior nexus. During this time, some scholars have integrated a traditional technique for accessing environmental perception, the sketch map, with this newer technology. This article provides a review and critical assessment of the way GIS has been used to understand fear of crime, specifically through the integration of sketch maps. This focus is framed by an overview of substantive and methodological concerns and concludes with a discussion of continued research needs. As behavioral responses to fear of crime are acknowledged to impact physical and mental health and overall well-being, in addition to the viability of neighborhoods, research in this area will continue apace. However, for integration of sketch maps in GIS to be a valuable methodological contributor to this line of inquiry, users of the approach must understand its complexities. This article outlines these issues so that they may be considered in future research and may improve the ability for this approach to yield new understanding of fear of crime.     

Conformance Testing for the Spatial Data Transfer Standard

The Spatial Oata Transfer Standard (SOTS) was approved as Federal Information Processing Standard (FIPS) 173, effective February 1993. Federal agencies and geographic information system vendors currently are developing SOTS encoding and decoding capabilities. A program is being developed to test encoders and decoders for conformance to the requirements of SOTS profiles. A series of test points will specify SOTS requirements that can be tested by software or by nonautomated methods. By certifying SOTS products, the conformance testing program will benefit both vendors and users of the SOTS.     

The Spatial Data Transfer Standard (FIPS 173): A Management Perspective

The Spatial Data Transfer Standard (SDTS) was approved by the Department of Commerce as Federal Information Processing Standard (FIPS) 173 on July 29, 1992. As a FIPS, the SDTS will serve as the national spatial data transfer mechanism for all federal agencies and will be available for use by state and local governments, the private sector, and research organizations. FIPS 173 will transfer digital spatial data sets between different computer systems, making data sharing practicable. This standard is of significant interest to users and producers of digital spatial data because of the potential for increased access to and sharing of spatial data, the reduction of information loss in data exchange, the elimination of the duplication of data acquisition, and the increase in the quality and integrity of spatial data. The success of FIPS 173 will depend on its acceptance by users of spatial data and by vendors of spatial information systems. Comprehensive workshops are being conducted, and the tools and procedures necessary to support FIPS 173 implementations are being developed. The U.S. Geological Survey, as the FIPS 173 maintenance authority, is committed to involving the spatial data community in various activities to promote acceptance of FIPS 173 and to providing case examples of prototype FIPS 173 implementations. Only by participating in these activities will the members of the spatial data community understand the role and impact of this standard.     

Explaining Map-reading Performance Efficiency: Gender,Memory, and Geographic Information

This paper explains the performance of a map-reading task that required subjects to locate a state on a map of the United States after being given the state's name. Response times and accuracy were hypothesized to be a function of differences among the decision makers and among the states. The cognitive science literature suggests that variation in performance can be explained by the interaction of biological and environmental variables. Individual differences in gender, working memory capacity, and brain lateralization were hypothesized to affect performance of the spatial task. Results indicated gender could be a more informative variable than sex. Subjects, who identified with both feminine and masculine characteristics, had the fastest mean response times. Subjects, who did not identify with feminine or masculine characteristics, had the most accurate responses. Subjects who combined higher verbal and spatial working memory capacities had both the fastest and most accurate performances. The results supported other studies indicating a non-linear relationship relating sex, brain lateralization, and accuracy. Covariates related to gravity model variables were also significantly related to performance.     

Opportunities for Use of the Spatial Data Transfer Standard at the State and Local Level

Dramatic changes in the way that spatial data have been collected and processed over that last 20 years is leading to a rethinking and restructuring on the most efficient ways to handle geographical information. These changes are taking place at the federal, state, and local governmental levels with great potential for the private sector as well. The formal adoption of the Spatial Data Transfer Standard (SDTS) as the federal database transfer standard for spatial databases signals a new era in this long chain of developments. It offers more flexible and efficient database transfers than earlier tools, and will become the workhorse for implementing the new National Spatial Data Infrastructure. It offers organizations a standard that will make possible and practical a much wider sharing of databases than is currently being done today. Use of the SDTS presents an opportunity to many organizations to share data more easily and reduce the duplication of expensive spatial database resources.     

Volunteered Geographic Information: A Bicycling Enthusiast Perspective

Mapping technologies have made considerable strides in recent decades. Global positioning systems (GPS), remote sensing satellites, Web-based mapping services, and geographic information systems (GIS) have facilitated the collection, distribution, analysis, and ultimately interaction with geospatial information. In particular, portable GPS have altered how individuals participate in mapping. Individuals can use GPS to collect tracings of their personal interactions with the environment. These interactions can then be uploaded to one of many available Web-based mapping services. Once uploaded, the geospatial data can be mapped and shared among the broader community of users. Such volunteered geographic information (VGI) exemplifies the conceptualization of an individual collecting, mapping, and sharing personal geographic information. This paper focuses on challenges surrounding VGI. To help place these challenges in a broader context, specialized Web services and GPS technologies developed for the bicycling community will serve as examples of the current status and future prospects of VGI.     

Interrogating Land Cover Categories: Metaphor and Method in Remote Sensing

The increasing sophistication of classification techniques used in land use and land cover analysis has not been matched by attention to the origin and effects of land cover categories. While classifications appear unproblematic and self-evident, they carry with them their own histories, meanings and effects, which remain largely unexamined. In an effort at such scrutiny, we examine the origins of land cover categories deployed in remote sensing and conclude that categories are theory-laden metaphors and occur epistemologically prior to any clustering algorithm, no matter how sophisticated. We describe the problematic effects that the imposition of classification systems in place of in situ knowledge of the landscape can have, especially in a colonial or post-colonial context. As an alternative to imposed classification, we propose and demonstrate an empirical technique based upon a growing body of work in participatory GIS. The method compares image classifications based on local and expert knowledge, using a case study from Rajasthan, India, concluding that differing metaphors of landscape lead to divergent measures of land cover.     

对美国2004年GPS新政策的初步看法

简要地回顾美国GPS政策发展历程之后，列出了2004年GPS新政策的要点，对这一政策作了初步评论。目的是提请更多的人参与分析，这对制订我国的政策是有益的。     

长沙市地籍测绘业务管理系统设计与开发

分析了长沙市国土资源局地籍测绘队的测绘业务需求,详细介绍了系统结构与数据组织方式,最后利用Visual Basic平台开发一套地籍测绘业务管理系统,该系统弥补了目前很多软件在打印宗地图和地籍调查表的缺陷,能够方便地生成包含多块面积的宗地图,以及打印电子地籍调查表。     

A new,high-resolution geoid for Canada and part of the U.S. by the 1D-FFT method

A new, high-resolution and high-precision geoid has been computed for the whole of Canada and part of the U.S., ranging from 35°N to about 90°N in latitude and 210°E to 320°E in longitude. The OSU91A geopotential model complete to degree and order 360 was combined with a 5 × 5 mean gravity anomaly grid and 1km × 1km topographical information to generate the geoid file. The remove-restore technique was adopted for the computation of terrain effects by Helmert's condensation reduction. The contribution of the local gravity data to the geoid was computed strictly by the 1D-FFT technique, which allows for the evaluation of the discrete spherical Stokes integral without any approximation, parallel by parallel. The indirect effects of up to second order were considered. The internal precision of the geoid, i.e. the contribution of the gravity data and the model coefficients noise, was also evaluated through error propagation by FFT. In a relative sense, these errors seem to agree quite well with the external errors and show clearly the weak areas of the geoid which are mostly due to insufficient gravity data coverage. Comparison of the gravimetric geoid with the GPS/levelling-derived geoidal heights of eight local GPS networks with a total of about 900 stations shows that the absolute agreement with respect to the GPS/levelling datum is generally better than 10 cm RMS and the relative agreement ranges, in most cases, from 4 to 1 ppm over short distances of about 20 to 100km, 1 to 0.5 ppm over distances of about 100 to 200 km, and 0.5 to 0.1 ppm for baselines of 200 to over 1000 km. Other existing geoids, such as UNB90, GEOID90 and GSD91, were also included in the comparison, showing that the new geoid achieves the best agreement with the GPS/levelling data.Presented at theIAG General Meeting, Beijing, P.R. China, Aug. 6–13, 1993     

美国国家天基PNT概况

简要介绍美国国家天基PNT推出背景、管理机构、相关政策和PNT体系结构及对GPS系统的影响和GPS的改进活动,并从PNT政策和GPS系统的安全两个角度分析了PNT的安全。     

Cartographic Software Capabilities and Data Requirements: Current Status and a Look toward the Future

In this article, we suggest that a universally accepted cartographic software program does not currently exist and has never existed, but mapping software capabilities are improving, and cartographers should be involved software developments for map making. We describe the current state of software development and explore what an ideal solution for the future would be. In a related vein, GIS and other data are not generally designed for cartography, but we are learning how they can be, and cartographers should also be involved in the modeling of GIS and other data used for map making.     

变更地籍调查及地籍管理信息系统建设的实践

土地是国家重要的资源,如何使用和管理好有限的土地资源,是各级政府和国土管理部门的重要职责。要管理和使用好国土资源,必须准确地查清现有土地的类型、面积、利用情况、使用者情况等方面的信息,并且能及时掌握其变更及历史沿革并展现出来。近年来随着城市建设的空前发展以及土地有偿使用法规的实施,地籍的变更日益频繁。对于如此数量巨大、来源多样、变更频繁的信息,传统的作业方式与管理模式已经越来越不能满足现代化土地管理的需要。因此,应用高新技术特别是信息技术和GIS技术,推进地籍管理和服务主流程的信息化,提高地籍工作的科学化和现代化水平势在必行。     

地籍测量绘图系统的研究与实践

结合实际介绍了地籍测量绘图系统的主要功能及应用。     

复合地块的拓扑类型计算与应用

按照简单地块的8种拓扑关系分类定义,计算简单地块的拓扑关系。将复合地块的外边界与空洞分离为m＋1个（m是空洞数）简单多边形,分别计算外边界之间、空洞之间、外边界与空洞之间的拓扑关系,并且按照不同的拓扑关系组合,计算复合地块的8种拓扑关系。