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51.
Iain Hay 《The Professional geographer》2016,68(1):159-165
Although journal editing is central to scholarly enterprise, helping to maintain academic standards and shape disciplines, it is frequently discouraged within the academic assemblages that depend on it. Following recent contributions by geographers to discussions on academic service such as book editing and reviewing, this article explores some ironies and paradoxes of journal editing. It first discusses the challenges of journal editing as well as its problematic place in “academic capitalism.” It then examines professional and personal rewards of journal editing. Despite strong disincentives, journal editing offers valuable opportunities for self-development and deepening professional networks, as well as for refining the discipline. 相似文献
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Ramón Piedrafita Rubén Béjar Rubén Blasco Alvaro Marco F. Javier Zarazaga-Soria 《International Journal of Digital Earth》2018,11(8):761-782
In the current world, it is easy to listen that everybody and everything is connected. Over this connected world, the concept of location-based services has grown in order to provide digital services in everyplace and at every time. Nevertheless, this is not 100% true because the connection is not guaranteed for many people and in many places. These are the Degraded Communications Environments (DCE), environments where the availability of high-speed communications is not guaranteed in at least the 75% of the time. This paper works over the experience of a previous work in developing light protocols that do not need broadband for communication. This work provides an extension of these protocols for the inclusion of mobile devices as elements of the communication process and a set of libraries to allow the development of applications in DCE. The work done has involved the development of two frameworks: an Android framework that makes the incorporation of Android devices easier and a server-based framework that provides the server side for the development of the referred applications. A use case that uses these two frameworks has been developed. Finally, all technology developed is available throw a public Git repository. 相似文献
54.
Erik H. Schmidt Budhendra L. Bhaduri Nicholas Nagle Bruce A. Ralston 《地理信息系统科学与遥感》2018,55(6):860-879
For many researchers, government agencies, and emergency responders, access to the geospatial data of US electric power infrastructure is invaluable for analysis, planning, and disaster recovery. Historically, however, access to high quality geospatial energy data has been limited to few agencies because of commercial licenses restrictions, and those resources which are widely accessible have been of poor quality, particularly with respect to reliability. Recent efforts to develop a highly reliable and publicly accessible alternative to the existing datasets were met with numerous challenges – not the least of which was filling the gaps in power transmission line voltage ratings. To address the line voltage rating problem, we developed and tested a basic methodology that fuses knowledge and techniques from power systems, geography, and machine learning domains. Specifically, we identified predictors of nominal voltage that could be extracted from aerial imagery and developed a tree-based classifier to classify nominal line voltage ratings. Overall, we found that line support height, support span, and conductor spacing are the best predictors of voltage ratings, and that the classifier built with these predictors had a reliable predictive accuracy (that is, within one voltage class for four out of the five classes sampled). We applied our approach to a study area in Minnesota. 相似文献
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中国对外开放口岸布局研究 总被引:11,自引:0,他引:11
本文共分五个部分。1、口岸分类及功能:按口岸的重要性及管理层次分类;按口岸性质及运输方式分类;按口岸所处地带及对外职能分类。2、口岸的基本结构:包括对外运输系统、对外贸易系统、监督检查系统、服务系统和综合管理系统。3、口岸布局与区域开发。4、中国口岸布局四大地域系统:沿海沿江沿边口岸开放地域系统和内陆(沿路)口岸开放地域系统。5、关于改善开放口岸体系的建议:口岸设置要为外向型经济服务,结合国际大通道建设开辟新口岸,大力发展航空网设置新航空港口岸,沿江内陆区口岸类型要多样化,完善现有开放口岸系统。 相似文献
57.
D. S. Young 《Geotechnical and Geological Engineering》1986,4(1):3-13
Summary An example of the generalized probabilistic approach to slope analysis is given through a case study on an iron ore mine. A step by step engineering procedure is described, so that a practical application can be made to other structures under different field conditions. 相似文献
58.
Summary An overview of economics and design consideration for explosive overburden casting is given and the criteria for the successful application of this technique are discussed. These criteria are: blast design, economic considerations and environmental considerations. Explosive overburden casting may effect considerable cost savings if the market for increased production is available. However, if a fixed sales constraint exists the economic benefits of explosive overburden casting may be marginal and an extensive economic analysis is warranted. 相似文献
59.
The dynamic response of offshore wind turbines is affected by the properties of the foundation and the subsoil. The aim of this paper is to evaluate the dynamic soil–structure interaction of suction caissons for offshore wind turbines. The investigations include evaluation of the vertical and coupled sliding–rocking vibrations, influence of the foundation geometry and examination on the properties of the surrounding soil. The soil is simplified as a homogenous linear viscoelastic material and the dynamic stiffness of the suction caisson is expressed in terms of dimensionless frequency‐dependent coefficients corresponding to different degrees of freedom. The dynamic stiffness coefficients for the skirted foundation are evaluated using a three‐dimensional coupled boundary element/finite element model. Comparisons with known analytical and numerical solutions indicate that the static and dynamic behaviours of the foundation are predicted accurately using the applied model. The analysis has been carried out for different combinations of the skirt length, Poisson's ratio of the subsoil and the ratio of the soil stiffness to the skirt stiffness. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
60.
开放式地理信息系统(OpenGIS)与互操作技术分析 总被引:8,自引:0,他引:8
地理信息系统技术在取得巨大发展的同时,其孤立性、封闭性的缺陷越来越不适合现代信息社会的要求,开放式地理信息系统(OpenGIS)规范和互操作技术的提出,不仅为数据共享提供了崭新的思路,而且将GIS带入了开放的时代,从而使得各个系统间实现不同类型地理数据和地理处理方法的透明访问成为可能。本文主要就OpenGIS规范和互操作技术作了一些探讨,最后结合我国的实际情况,分析了OpenGIS在我国的应用现状与未来展望。 相似文献