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141.
《International Journal of Digital Earth》2013,6(9):727-749
Disaster management and in particular disaster response phase are highly time-sensitive and dynamic processes, demanding that real-time information reaches disaster responders prior making critical decisions. During the last decade, disaster management has been widely enabled through utilizing spatial data sourcing and related technologies in the whole process of collection, access, and usage of disaster information. Currently, there are unique challenges that cannot be met without incorporating in situ sensing as an emerging technology for sourcing and managing disaster information. These include (1) high temporal and spatial resolution of information, (2) broad range of disaster data, and (3) automated operations. Incorporating in situ sensing into the disaster management process can potentially address such challenges by providing data that support all of these requirements. Following an examination of current concepts and methods for integrating multisourced sensors, a framework of the requirements for integrating in situ sensors for disaster management, is suggested. Based on this framework and its components, an evaluation of the methods is developed and applied. The results highlight that information integration of multisourced sensors is a major challenge and has not yet adequately addressed for sensor data enablement of disaster management. 相似文献
142.
保护性耕作改善东北农田黑土土壤生物多样性及其生态功能 总被引:2,自引:0,他引:2
保护性耕作是攻克黑土地保护和利用的核心技术之一。研究立足中国科学院黑土区农业生态重点试验室保护性耕作长期定位试验基地,系统梳理总结了农田黑土土壤生物多样性对保护性耕作的响应特征。与传统耕作相比,保护性耕作显著增加各生物类群(微生物、线虫、跳虫、螨类及蚯蚓)的物种丰富度(1%~8%)、数量(25%~57%)和生物量(30%~50%),提高食物网网状结构的复杂性及各营养级间的连通性(14%~32%),促进土壤生物在固土蓄水、土壤碳固存、氮素高效利用以及稳定作物产量四方面生态功能的可持续性发挥。研究结果表明,实施保护性耕作可有效利用土壤生物的功能潜力,实现东北黑土区农田生态系统的健康发展、服务国家粮食安全产业带建设和现代农业发展。 相似文献
143.
黄海鱼类食物网的研究 总被引:80,自引:1,他引:80
于1985年3月—1986年10月和1988年5月间,对黄海海域40科69属80种鱼的食性及其相互关系进行了较系统地调查、分析。结果表明:1.黄海鱼类饵料分为4个生态类型;2.黄海鱼类摄食有明显的季节变化;3.黄海鱼类基本属于第二—第四营养级;4.日本鳀、脊尾褐虾、太平洋磷虾等优势饵料生物在黄海鱼类食物网中起着举足轻重的作用;5.黄海多数鱼类间的食物竞争关系基本是协调的。 相似文献
144.
David Forrest 《The Cartographic journal》2013,50(3):213-214
In recent years, the concepts of usability, user experience, and user-centricity have gained in interest. Digital applications, developed in line with criteria related to these approaches, ask for a deeper understanding of users and their requirements. But, even though there is a wide range of methods available, the creation of user-centric applications with good usability and user experience still poses great challenges for developers. This is also true for web maps, i.e. web map applications, which today are ubiquitous on the Internet. They have evolved into an important information and communication tool and address users who do not possess any specific knowledge of Geoinformatics (GI) or Cartography. Despite the efforts made to meet the requirements and preferences of laymen, these users still often face problems when dealing with web map applications. This refers to aspects of design, content, and functionality. Here, participatory design, which is well-known in the field of Software and Web Engineering, might provide a suitable means. By engaging users directly and actively in the application development process, developers are able to gain a profound understanding of the users and their needs. However, there are several open questions regarding the use of participatory design for designing and implementing web map applications: What does the use of participatory design in web map development processes look like in detail? How and to what degree can users be involved in the development processes? Which added values exist? These questions are addressed by the project YouthMap 5020, whose main goal it was to create a prototype youth-centric web map for the Austrian city of Salzburg (zip code 5020). Applying the approach of participatory design, about 120 teenage pupils from several local schools were involved in all kinds of tasks related to the phases of generating the youth-centric Salzburg web city map. Experience and knowledge gained thereby allowed elaborating recommendations generally useful for generating youth-centric web map applications. 相似文献
145.
146.
Abstract Limitations of the current land records systems in Belize, Central America, led leaders of the Ministry of Natural Resources to initiate this feasibility study for a computer-aided land information system (LIS). Land records in Belize have been based on the British Torrens land tenure system, which maintains five sets of records along with informative maps. One paper file is maintained for each title application and records are continually circulated between seven locations throughout the country, resulting in up to 3 years to complete the process of title registration. A LIS will permit quick access to land records and eliminate most of the current problems, and will merge with a geographic information system being developed for Belize. 相似文献
147.
148.
Aengus McCullough Philip James Stuart Barr 《International journal of geographical information science》2013,27(10):1939-1957
The geospatial sensor web is set to revolutionise real-time geospatial applications by making up-to-date spatially and temporally referenced data relating to real-world phenomena ubiquitously available. The uptake of sensor web technologies is largely being driven by the recent introduction of the OpenGIS Sensor Web Enablement framework, a standardisation initiative that defines a set of web service interfaces and encodings to task and query geospatial sensors in near real time. However, live geospatial sensors are capable of producing vast quantities of data over a short time period, which presents a large, fluctuating and ongoing processing requirement that is difficult to adequately provide with the necessary computational resources. Grid computing appears to offer a promising solution to this problem but its usage thus far has primarily been restricted to processing static as opposed to real-time data sets. A new approach is presented in this work whereby geospatial data streams are processed on grid computing resources. This is achieved by submitting ongoing processing jobs to the grid that continually poll sensor data repositories using relevant OpenGIS standards. To evaluate this approach a road-traffic monitoring application was developed to process streams of GPS observations from a fleet of vehicles. Specifically, a Bayesian map-matching algorithm is performed that matches each GPS observation to a link on the road network. The results show that over 90% of observations were matched correctly and that the adopted approach is capable of achieving timely results for a linear time geoprocessing operation performed every 60 seconds. However, testing in a production grid environment highlighted some scalability and efficiency problems. Open Geospatial Consortium (OGC) data services were found to present an IO bottleneck and the adopted job submission method was found to be inefficient. Consequently, a number of recommendations are made regarding the grid job-scheduling mechanism, shortcomings in the OGC Web Processing Service specification and IO bottlenecks in OGC data services. 相似文献
149.
150.