Java手机地图服务系统研究与实现

基于位置的服务（LBS）是指为移动设备的用户提供一系列个性化的与位置相关的服务。在分析了JSR-179规范的基础上,详细讨论了基于JSR-179规范的J2ME手机应用开发架构,并给出了J2ME手机地图服务系统的实现方法及相关程序代码。系统的实现为用户移动地、快速地提供地理信息获取支持。     

基于J2EE与ArcIMS的WebGIS构建研究与实践

设计了一个WebGIS应用系统的框架,构建了基于ArcIMS的空间信息服务体系,设计了基于非空间数据的业务逻辑计算的ＥＪＢ组件。     

IPCC emission scenarios: How did critiques affect their quality and relevance 1990–2022?

Long-term global emission scenarios enable the analysis of future climate change, impacts, and response strategies by providing insight into possible future developments and linking these different climate research elements. Such scenarios play a crucial role in the climate change literature informing the Intergovernmental Panel on Climate Change’s (IPCC) Assessment Reports (ARs) and support policymakers. This article reviews the evolution of emission scenarios, since 1990, by focusing on scenario critiques and responses as published in the literature. We focus on the issues raised in the critiques and the possible impact on scenario development. The critique (280) focuses on four areas: 1) key scenario assumptions (40%), 2) the emissions range covered by the scenarios and missing scenarios (25%), 3) methodological issues (24%), and 4) the policy relevance and handling of uncertainty (11%). Scenario critiques have become increasingly influential since 2000. Some areas of critique have decreased or become less prominent (probability, development process, convergence assumptions, and economic metrics). Other areas have become more dominant over time (e.g., policy relevance & implications of scenarios, transparency, Negative Emissions Technologies (NETs) assumptions, missing scenarios). Several changes have been made in developing scenarios and their content that respond to the critique.