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地球系统科学综述 总被引:14,自引:0,他引:14
首先从人类面临全球性的重大问题、地球系统的全球化和地球系统科学的关系与传统地球科学三个方面介绍了地球系统科学提出的背景,阐述了地球系统科学国内外研究现状.然后,详细介绍了地球系统科学的概念与研究方法,主要包括研究思路、基本概念、地球系统过程、全球——区域信息获取、海量信息处理和分析及地球系统模型等.第三,构建了地球系统科学理论基础.主要包括:地球系统的连续动态系统、离散动态系统、地球系统的随机性、地球系统的自组织和地球系统的简单巨系统与复杂巨系统,重点介绍了地球系统科学子系统与各圈层相互作用的动力学模型与效应.第四,概述了地球系统的数字表达一数字地球和地球系统科学是可持续发展战略科学基础.最后,简述了中国开展地球系统科学研究的方向和面临的主要科学问题。 相似文献
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本文首先简要介绍了地震现场建筑物安全性鉴定辅助决策系统的定义、用途及发展现状,并阐释了将其应用于地震现场中的作用、方法及意义。此外,还介绍了此辅助系统的功能和设计分析及该系统的层次结构,重点介绍了该系统的计算模型及其理论根据以及模型算法分析。深入研究了辅助系统的功能、业务流程和总体设计,讨论了系统的需求、数据的采集与管理、模型计算、结果输出、查询、统计和分析等功能,并简要介绍了辅助系统的界面设计方法及界面框图,同时对系统的进一步扩展提出了看法。 相似文献
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飞信服务在地震软件系统中的集成和应用 总被引:1,自引:1,他引:0
通过研究飞信服务在Linux系统中的应用,部署一套基于Linux系统的短消息通知平台,同时根据上海市地震局现有应用系统,分析了局内网络监控系统、OA数据库备份系统、值班系统在用户使用过程中的预警提示的欠缺,提出了一种通过飞信服务解决问题的新方法,即将短消息通知平台集成于上述应用系统中,最终实现了台站设备故障短信告警,值班短信通知及OA数据库自动备份短信通知。 相似文献
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提出了一种自复位浮置物隔震系统,该系统采用双层正交导轨隔离水平地震,并通过预拉弹簧绳实现自复位。考虑系统摩擦与弹簧绳刚度,建立了自复位浮置物隔震系统的理论模型,完成了不同工况下的隔震系统振动台试验,结果表明输入地震波的加速度峰值越高,隔震系统的隔震率也会相应提升。在输入地震波加速度峰值为0.15、0.2、0.4、0.62 g时,隔震系统平均隔震率分别为50%、58%、75%、82%。在相同峰值的地震波及楼面波地震动输入下,隔震系统均具有良好的隔震效果且能够实现系统自复位。最后建立了浮置物隔震支座-浮置物体系的有限元模型,验证了隔震系统理论模型的有效性。 相似文献
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该系统提供了航空红外遥感资料的袢时采集和传输,为及时开展地震野外调查工作提供了一个有力的手段。该系统由红外传感器系统、机载站图像和数据实时处理系统、机载站通信系统、转发站通信系统、地面站接收系统、地面站图像和数据实时处理系统组成。 相似文献
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Y. Zhu Y. P. Li G. H. Huang L. Guo 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(3):693-704
In recent years, water shortages and unreliable water supplies have been considered as major barriers to agricultural irrigation water management in China, which are threatening human health, impairing prospects for agriculture and jeopardizing survival of ecosystems. Therefore, effective and efficient risk assessment of agricultural irrigation water management is desired. In this study, an inexact full-infinite two-stage stochastic programming (IFTSP) method is developed. It incorporates the concepts of interval-parameter programming and full-infinite programming within a two-stage stochastic programming framework. IFTSP can explicitly address uncertainties presented as crisp intervals, probability distributions and functional intervals. The developed model is then applied to Zhangweinan river basin for demonstrating its applicability. Results from the case study indicate that compromise solutions have been obtained. They provide the desired agricultural irrigation water-supply schemes, which are related to a variety of tradeoffs between conflicting economic benefits and associated penalties attributed to the violation of predefined policies. The solutions can be used for generating decision alternatives and thus help decision makers to identify desired agricultural irrigation targets with maximized system benefit and minimized system-failure risk. Decision makers can adjust the existing agricultural irrigation patterns, and coordinate the conflict interactions among economic benefit, system efficiency, and agricultural irrigation under uncertainty. 相似文献
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Derek Karssenberg 《水文研究》2002,16(14):2751-2766
An evaluation is made of the suitability of programming languages for hydrological modellers to create distributed, process‐based hydrological models. Both system programming languages and high‐level environmental modelling languages are evaluated based on a list of requirements for the optimal programming language for such models. This is illustrated with a case study, implemented using the PCRaster environmental modelling language to create a distributed, process‐based hydrological model based on the concepts of KINEROS‐EUROSEM. The main conclusion is that system programming languages are not ideal for hydrologists who are not computer programmers because the level of thinking of these languages is too strongly related to specialized computer science. A higher level environmental modelling language is better in the sense that it operates at the conceptual level of the hydrologist. This is because it contains operators that identify hydrological processes that operate on hydrological entities, such as two‐dimensional maps, three‐dimensional blocks and time‐series. The case study illustrates the advantages of using an environmental modelling language as compared with system programming languages in fulfilling requirements on the level of thinking applied in the language, the reusability of the program code, the lack of technical details in the program, a short model development time and learnability. The study shows that environmental modelling languages are equally good as system programming languages in minimizing programming errors, but are worse in generic application and performance. It is expected that environmental modelling languages will be used in future mainly for development of new models that can be tailored to modelling aims and the field data available. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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In this study, an inexact fuzzy-chance-constrained two-stage mixed-integer linear programming (IFCTIP) approach is developed for flood diversion planning under multiple uncertainties. A concept of the distribution with fuzzy boundary interval probability is defined to address multiple uncertainties expressed as integration of intervals, fuzzy sets and probability distributions. IFCTIP integrates the inexact programming, two-stage stochastic programming, integer programming and fuzzy-stochastic programming within a general optimization framework. IFCTIP incorporates the pre-regulated water-diversion policies directly into its optimization process to analyze various policy scenarios; each scenario has different economic penalty when the promised targets are violated. More importantly, it can facilitate dynamic programming for decisions of capacity-expansion planning under fuzzy-stochastic conditions. IFCTIP is applied to a flood management system. Solutions from IFCTIP provide desired flood diversion plans with a minimized system cost and a maximized safety level. The results indicate that reasonable solutions are generated for objective function values and decision variables, thus a number of decision alternatives can be generated under different levels of flood flows. 相似文献
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《Advances in water resources》2002,25(6):677-687
Several successful applications of optimal control theory (OCT) based on the Pontryagin's minimum principle have been recorded in literature. These applications were focused on optimizing the operating policy of multi-reservoir systems. In this study, the performance of OCT algorithm in designing multi-reservoir system is investigated. Three deterministic optimization models based on the OCT were developed to design the best storage strategies in a multi-reservoir system to supply water. Multi-objective programming methods were implemented in the three models in order to consider the two non-commensurate objectives of minimizing cost and water deficit. The applications of these models to a multi-reservoir system were compared to an existing dynamic programming model. The result of this study showed that in all cases, the developed OCT models presented sub-optimal solution in designing multi-reservoir systems. 相似文献
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Inexact fuzzy two-stage programming for water resources management in an environment of fuzziness and randomness 总被引:1,自引:1,他引:0
Qing Hu Guohe Huang Zhenfang Liu Yurui Fan Wei Li 《Stochastic Environmental Research and Risk Assessment (SERRA)》2012,26(2):261-280
A standard lower-side attainment values based inexact fuzzy two-stage programming (SLA-IFTSP) approach is proposed for supporting
multi-water resources management under multi-uncertainties. The method improves upon the existing inexact two-stage stochastic
programming by the introduction of a standard average lower-side attainment values based fuzzy linear programming. Multi-uncertainties
such as intervals, probabilistic and/or possibilistic distributions and their combinations in water resources management can
be directly communicated into the water allocation process. The risk of infeasibility caused by the random water availabilities
can be analyzed by imposing economic penalties when the designed water allocations would not be satisfied after the occurrence
of random seasonal flows. Based on the standard average lower-side attainment index, the fuzzy random relationships representing
various subjective judgments in the model can be transformed into corresponding deterministic ones without additional constraints,
and thus guarantee a higher computational efficiency. A hypothetical case regarding two-source water resources management
is adopted for demonstrating its applicability. Reasonable solutions have been generated. They provide desired water allocations
with maximized system benefit under different water availability levels. The solutions of intervals with different probabilities
can be used for generating decision alternatives. Comparisons between the solutions from SLA-IFTSP and those from ITSP are
also undertaken. They show that SLA-IFTSP can generate more reasonable water allocation patterns with higher net system benefits
than ITSP. 相似文献
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C. Xu Y. P. Li G. H. Huang Y. Zhou 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(6):1613-1627
In this study, a fuzzy-queue (FQ)-based inexact stochastic quadratic programming (SQP) method is developed through coupling FQ technique with inexact SQP. FQ-SQP improves upon the existing stochastic programming methods by considering the effects of queuing phenomenon during the water resources allocation process. FQ-SQP cannot only handle uncertainties expressed as interval values, random variables, and fuzzy sets, but also tackle nonlinearity in the objective function; more importantly, it can reflect the effects of FQ on water resources allocation and system benefit. The FQ-SQP model is applied to a case study of planning water resources management, where FM/FM/1 (fuzzy exponential interarrival time, fuzzy exponential service time, and one server) queue is incorporated within the SQP modeling framework. Based on α-cut analysis technique, interval solutions with fuzzy arrival and service rates have been generated, which result in different water resources allocation patterns as well as changed waiting water amounts and system benefits. Results indicate that consideration of queuing problem impacts on water resources allocation can provide more useful information for decision makers and gain in-depth insights into the effects of queuing problems for water resources allocation. 相似文献
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ISMISIP: an inexact stochastic mixed integer linear semi-infinite programming approach for solid waste management and planning under uncertainty 总被引:2,自引:1,他引:1
P. Guo G. H. Huang L. He 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(6):759-775
An inexact stochastic mixed integer linear semi-infinite programming (ISMISIP) model is developed for municipal solid waste
(MSW) management under uncertainty. By incorporating stochastic programming (SP), integer programming and interval semi-infinite
programming (ISIP) within a general waste management problem, the model can simultaneously handle programming problems with
coefficients expressed as probability distribution functions, intervals and functional intervals. Compared with those inexact
programming models without introducing functional interval coefficients, the ISMISIP model has the following advantages that:
(1) since parameters are represented as functional intervals, the parameter’s dynamic feature (i.e., the constraint should
be satisfied under all possible levels within its range) can be reflected, and (2) it is applicable to practical problems
as the solution method does not generate more complicated intermediate models (He and Huang, Technical Report, 2004; He et al. J Air Waste Manage Assoc, 2007). Moreover, the ISMISIP model is proposed upon the previous inexact mixed integer linear semi-infinite programming (IMISIP)
model by assuming capacities of the landfill, WTE and composting facilities to be stochastic. Thus it has the improved capabilities
in (1) identifying schemes regarding to the waste allocation and facility expansions with a minimized system cost and (2)
addressing tradeoffs among environmental, economic and system reliability level. 相似文献
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An interval-parameter multi-stage stochastic programming model for water resources management under uncertainty 总被引:1,自引:0,他引:1
In this study, an interval-parameter multi-stage stochastic linear programming (IMSLP) method has been developed for water resources decision making under uncertainty. The IMSLP is a hybrid methodology of inexact optimization and multi-stage stochastic programming. It has three major advantages in comparison to the other optimization techniques. Firstly, it extends upon the existing multi-stage stochastic programming method by allowing uncertainties expressed as probability density functions and discrete intervals to be effectively incorporated within the optimization framework. Secondly, penalties are exercised with recourse against any infeasibility, which permits in-depth analyses of various policy scenarios that are associated with different levels of economic consequences when the promised water-allocation targets are violated. Thirdly, it cannot only handle uncertainties through constructing a set of scenarios that is representative for the universe of possible outcomes, but also reflect dynamic features of the system conditions through transactions at discrete points in time over the planning horizon. The developed IMSLP method is applied to a hypothetical case study of water resources management. The results are helpful for water resources managers in not only making decisions of water allocation but also gaining insight into the tradeoffs between environmental and economic objectives. 相似文献
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An inexact double-sided fuzzy chance-constrained programming (IDFCCP) method was developed in this study and applied to an agricultural effluent control management problem. IDFCCP was formulated through incorporating interval linear programming (ILP) into a double-sided fuzzy chance-constrained programming (DFCCP) framework, and could be used to deal with uncertainties expressed as not only possibility distributions associated with both left- and right-hand-side components of constraints but also discrete intervals in the objective function. The study results indicated that IDFCCP allowed violation of system constraints at specified confidence levels, where each confidence level consisted of two reliability scenarios. This could lead to model solutions with high system benefits under acceptable risk magnitudes. Furthermore, the introduction of ILP allowed uncertain information presented as discrete intervals to be communicated into the optimization process, such that a variety of decision alternatives can be generated by adjusting the decision-variable values within their intervals. The proposed model could help decision makers establish various production patterns with cost-effective water quality management schemes under complex uncertainties, and gain in-depth insights into the trade-offs between system economy and reliability. 相似文献