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141.
Abstract

Abstract A flood forecasting system is a crucial component in flood mitigation. For certain important large-scale reservoirs, cooperation and communication among federal, state, and local stakeholders are required when heavy flood events are encountered. The Web-based environment is emerging as a very important development and delivery platform for real-time flood forecasting systems. In this paper, the findings of a case study are presented of the development of a Web-based flood forecasting system for reservoirs using Java 2 platform Enterprise Edition (J2EE). J2EE of Sun Microsystems is chosen as the development solution for the Web-based flood forecasting system, Weblogic 6.0 of BEA as the container provider, and JBuilder 7.0 of Borland as the development tool. One of the key objectives in this project is to establish a collaborative platform for flood forecasting via Web technology in order to render hydrological models and data available to stakeholders and experts involved and thus offer an efficient medium for transferring and sharing information, knowledge and experiences among them. Compared with general Web-based query systems and traditional flood forecasting systems, the Web-based flood forecasting system is more focused on the on-line analysis of model-based forecasting of floods and provides opportunities for improving the transfer of information and knowledge from the hydrological scientists and managers to decision makers. Finally, a prototype system is used to demonstrate the system application.  相似文献   
142.
高分辨率遥感对地观测为我们从空间与时间2个维度客观反演地表格局—过程提供了有效的技术支撑。本文遵循时空协同的研究思路,基于高分辨率遥感影像,开展了农业遥感领域2个典型的问题研究:① 提出了一种基于影像视觉特征的耕地分区分层提取方法,该方法在利用DEM数据进行分区的基础上,根据不同区域内耕地所呈现的几何特征和纹理特征差异,分别设计了不同的耕地提取模型;② 构建了一种地块尺度的作物生长参数反演方法,方法以地块为基本单元,在空间、时间及属性组合约束下进行作物理化参数反演。本研究以贵州省安顺市西秀区和广西扶绥县耕地提取进行了耕地地块提取示范,以扶绥县进行了基于耕地地块和中空间分辨率时间序列遥感数据的甘蔗叶面积指数反演。其中,对于安顺市西秀区的耕地地块提取结果而言,形态精度(IoU)大于0.7的地块超过60%,规则耕地、梯田以及林草地等的类型精度均超过了80%;对于扶绥县甘蔗叶面积指数反演的结果而言,其结果可以较为精确地反映出基地甘蔗与非基地甘蔗的差异,基地甘蔗在品质上要优于非基地甘蔗。西南山地区的耕地形态提取/类型判别和地块甘蔗叶面积指数应用验证均证明了方法的可行性。结果表明,协同使用多源高分辨率数据是实现精准农业遥感研究的有效途径。  相似文献   
143.
信息技术的快速发展使身份认证机制的安全性得到越来越广泛的关注.但现有的身份认证机制存在着隐私泄露等风险,这就要求设计出更加可靠的身份认证机制.本文利用区块链的去中心化、不可篡改等特性,设计出基于区块链的多方协作安全身份认证机制.在实现可靠身份认证的同时,保证信息的权威性,在一定程度上减少数据冗余,并提高身份认证效率,保证全面且准确的身份认证.最后实现支持多个数据服务商对身份信息进行加密签名,保护数据隐私,以及多方共享数据的身份认证系统.  相似文献   
144.
针对农用拖拉机智能化程度低,以及现有的人工智能水平尚无法完全实现自主驾驶控制拖拉机等问题,本文设计一种基于人机协作的拖拉机驾驶机器人.拖拉机驾驶机器人可以对拖拉机进行快速、无损、智能化升级,其结构由转向控制机械手、换挡机械手、旋耕机升降控制机械手和踏板控制机械腿等组成.通过研究人机协作的控制方法,提出了人机协作介入准则和基于转向电机电流反馈扭矩检测的人机协作模式切换方法,研制了原理样机验证拖拉机驾驶机器人的可行性和人机协作控制策略的有效性,对促进精准农业,提高现代农业智能化装备水平具有重要的现实意义.  相似文献   
145.
Arpad Cseh 《Climate Policy》2019,19(2):139-146
The global and long-term nature of climate change conflicts with the self-interest and short-term dominated priorities of decision-makers. Climate change mitigation makes sense at the global level, but not at the level of the individual decision-maker. This conflict has been and remains the main obstacle to effective global cooperation and mitigation. This paper proposes a framework that aligns climate action with short-term self-interest through results-based payments to governments. Its key components are: determining an emission benchmark for each country as well as a price for carbon saving; paying countries annually for reducing emissions below their respective benchmark; a new international fund to finance these annual payments by borrowing capital from private investors; and repaying borrowings in the long-term through payments made by countries to the fund based on a pre-determined allocation mechanism. This framework would offer important benefits over an approach focused on allocating climate action or a carbon budget among countries. These include the improved prospect of reaching an effective climate agreement and delivering fast and dramatic mitigation thanks to stronger political commitment, the transformation of short-term self-interest from an obstacle into a driver of climate action, and the additional financing created. The paper also proposes a pilot scheme focusing on hydrofluorocarbon emissions with a considerably lower financing requirement. This offers the possibility of an alternative financing mechanism, and thus a faster and more straightforward implementation path. Short-term financial incentives offered to governments could turn policy action from a burden into an opportunity from their perspective unlocking a huge potential for timely mitigation.

Key policy insights

  • A new international framework that offers short-term, results-based payments to governments to promote mitigation action could lead to much more effective global mitigation and international cooperation.

  • The financing of such an approach could be solved through a novel financing structure, backed by the long-term commitments of participating countries and thus aligning the timeframe of the financial costs of mitigation with its climate benefits.

  • The effectiveness of results-based payments and the concept behind this new approach could be proven through a pilot scheme focusing on hydrofluorocarbon emissions.

  相似文献   
146.
《The Journal of geography》2012,111(5):202-215
Abstract

Short-term international field study is an attractive alternative for many students to traditional, longer-term study abroad programs. We present a discussion of critical planning, administrative, and curricular elements related to the development and implementation of such courses. In doing so, we share a number of checklists and planning tools that other instructors may find helpful in the context of developing their own international field studies courses. In addition, we provide representative examples and experiences from two short-term international courses taught by the authors in the Geography Department at Shippensburg University.  相似文献   
147.
《The Journal of geography》2012,111(5):216-219
Abstract

The Geographical Association (GA) is an international association of over 10,000 geography educators headquartered in Sheffield, England. The National Council for Geographic Education (NCGE) and the GA have similar goals. The GA's annual conferences provide an excellent opportunity to begin geography education partnerships between the NCGE and the GA. Operating exhibits and teaching workshops on geographic information systems at the last three Geographical Association conferences at universities in England afforded the opportunity to network with teachers and pave the way for future collaboration.  相似文献   
148.
国际河流公平合理利用原则:回顾、反思与消解   总被引:1,自引:0,他引:1  
公平合理利用原则是国际水法的一项基本原则,它的适用对保护国际河流水资源及协调国际河流水资源利用冲突具有重要的意义。但伴随全球淡水资源日益匮乏,水资源利用冲突频发,公平合理利用原则的局限性也日益凸显。要摆脱公平合理利用原则难以具体运用于实践的困境,一方面需在国际法律文件中对"公平合理利用"进一步界定和完善,另一方面,需结合实际情况缔结国际河流水资源公平合理利用条约并设置相应的配套措施,以保障国际河流水资源公平合理利用原则得以真正实现。  相似文献   
149.
 从气候变化的角度看,2007年是具有里程碑意义的一年。无论从科学领域的最新研究成果,还是到人们的切身感受,或者到国际社会讨论的焦点问题以及应对气候变化的具体行动,2007年都将当之无愧地成为"气候变化年"。  相似文献   
150.
李萍阳 《气象》2010,36(2):136-141
第18届国际生物气象会议于2008年9月22—26日在日本东京举行。通过简要介绍了这次会议的情况,概括了近年来生物气象研究的进展与动向。从ICB2008各会场的交流内容和讨论可以看出,未来生物气象研究关注的重点问题主要包括以下六个方面:(1)人类生物气象学领域的热浪与健康预警系统、医疗气象、室外工作热环境评价及医疗天气预报研究与应用。(2)城市气候特征与评价及减缓措施研究。(3)气候变化对极端天气、气候事件的影响。(4)气候变化对农业的影响。(5)动物对气象条件和气候变化的响应。(6)污染物跨国输送与国际环境合作研究。加强我国的生物气象研究是应对气候变化影响、以人为本、构建和谐社会的需要,可以为社会可持续发展提供科学依据和咨询建议。  相似文献   
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