Integrated assessment and modelling: Overview and synthesis of salient dimensions

Integrated assessment and its inherent platform, integrated modelling, present an opportunity to synthesize diverse knowledge, data, methods and perspectives into an overarching framework to address complex environmental problems. However to be successful for assessment or decision making purposes, all salient dimensions of integrated modelling must be addressed with respect to its purpose and context. The key dimensions include: issues of concern; management options and governance arrangements; stakeholders; natural systems; human systems; spatial scales; temporal scales; disciplines; methods, models, tools and data; and sources and types of uncertainty. This paper aims to shed light on these ten dimensions, and how integration of the dimensions fits in the four main phases in the integrated assessment process: scoping, problem framing and formulation, assessing options, and communicating findings. We provide examples of participatory processes and modelling tools that can be used to achieve integration.     

基于多智能体的集成维护系统建模

在归纳集成维护系统特性的基础上，阐述了集成维护系统建模的必要性，通过对结构化、面向对象和多智能体3种建模思想的分析比较，选择多智能体系统思想作为理论指导，结合Tropes方法研究构建了集成维护系统的模型，为系统设计、实施与维护提供了指导模板。     

A minimally invasive model data passing interface for integrating legacy environmental system models

This paper presents the Model Data Passing Interface (MODPI). The approach provides fine-grained, multidirectional feedbacks between legacy environmental system models through read and write access to relevant model data during simulation using a bidirectional, event-based, publish-subscribe system with a message broker. MODPI only requires commented directives in the original code and an XML linkage file with an optional custom data conversion module. Automated code generation, compilation, and execution reduce the programming burden on the modeler. Case study results indicated that MODPI required less code modifications within each model code base both before and after automated code generation, outperforming a baseline subroutine approach. Performance overhead for MODPI was minimal for the use case, offering speedup in some cases through parallel execution. MODPI is much less invasive than other techniques, potentially encouraging adoption by the modeling community in addition to maintainability and reusability of integrated model code.     

飞行／推进综合控制系统设计与仿真

飞机飞行控制系统与推进系统间有很强的耦合作用,单独设计和发动机控制系统已不能满足需要。该文在单4独研究外部干扰对飞行性能和发动机性能的影响的基础上,根据他们相互的关系,建立了飞行／推进系统一体化数学模型,并在此基础上进行了综合控制设计,对所建的模型进行了仿真,结果表明飞机飞行状态和发动机的工作确实有很强的耦合,同时本文所设计的飞行／推进综合控制系统具有优良的性能。     

A framework for integrated assessment of food production economics in South Asia under climate change

Agriculture is a sector vulnerable to climate change. The potential decline of crop yields from this vulnerability has important policy implications for food security in South Asia. In this study an integrated assessment modelling framework is proposed to link a global economic model with global climate models via an econometric model of crop productivity. It is then used to examine the impact of climate change on food security in individual South Asian countries by exploring the interaction between climate-induced productivity change and changes in food production and food prices. The results of our simulations suggest that unfavourable climate change can reduce food production significantly from the historical trend and create upward pressure on food prices. This, in turn, will have serious adverse impacts on food security in the South Asian region.     

电站仿真建模一体化环境

ＧＮＥＴ是新开发的电厂仿真图形建模一体化环境。ＧＮＥＴ建模环境完全采用图形化用主发口，使建模人员能够通过友好，方便的图形界面和数据库、模块，模型程序进行数据和信息的联系，从而支持从建模型模型验证的全过程。大大地方便了仿真建模工作。     

A model-based integrated assessment of land degradation by water erosion in a valuable Spanish rangeland

This paper presents an integrated assessment model aimed at evaluating land degradation by water erosion in dehesa rangelands in the Iberian Peninsula. The model is built following the system dynamics approach. The degradation risk is likened to the probability of losing a certain amount of soil within a number of years, as estimated over a great number of stochastic simulations. Complementary indicators are the average times needed to lose different amounts of soil over the simulations. A group of exogenous factors are ranked in order of importance. These factors are mainly climatic and economic and potentially affect soil erosion. Calibration is carried out for a typical dehesa defined over 22 working units selected from 10 representative farms distributed throughout the Spanish region of Extremadura. The degradation risk turns out to be moderate. The importance of climatic factors on soil erosion considerably exceeds that of those linked to human activities.     

Climate simulations and projections with a super-parameterized climate model

The mean climate and its variability are analyzed in a suite of numerical experiments with a fully coupled general circulation model in which subgrid-scale moist convection is explicitly represented through embedded 2D cloud-system resolving models. Control simulations forced by the present day, fixed atmospheric carbon dioxide concentration are conducted using two horizontal resolutions and validated against observations and reanalyses. The mean state simulated by the higher resolution configuration has smaller biases. Climate variability also shows some sensitivity to resolution but not as uniform as in the case of mean state. The interannual and seasonal variability are better represented in the simulation at lower resolution whereas the subseasonal variability is more accurate in the higher resolution simulation. The equilibrium climate sensitivity of the model is estimated from a simulation forced by an abrupt quadrupling of the atmospheric carbon dioxide concentration. The equilibrium climate sensitivity temperature of the model is 2.77 °C, and this value is slightly smaller than the mean value (3.37 °C) of contemporary models using conventional representation of cloud processes. The climate change simulation forced by the representative concentration pathway 8.5 scenario projects an increase in the frequency of severe droughts over most of the North America.     

Identifying parametric controls and dependencies in integrated assessment models using global sensitivity analysis

Integrated assessment models for climate change (IAMs) couple representations of economic and natural systems to identify and evaluate strategies for managing the effects of global climate change. In this study we subject three policy scenarios from the globally-aggregated Dynamic Integrated model of Climate and the Economy IAM to a comprehensive global sensitivity analysis using Sobol' variance decomposition. We focus on cost metrics representing diversions of economic resources from global world production. Our study illustrates how the sensitivity ranking of model parameters differs for alternative cost metrics, over time, and for different emission control strategies. This study contributes a comprehensive illustration of the negative consequences associated with using a priori expert elicitations to reduce the set of parameters analyzed in IAM uncertainty analysis. The results also provide a strong argument for conducting comprehensive model diagnostics for IAMs that explicitly account for the parameter interactions between the coupled natural and economic system components.     

Climate and human development impacts on municipal water demand: A spatially-explicit global modeling framework

Municipal water systems provide crucial services for human well-being, and will undergo a major transformation this century following global technological, socioeconomic and environmental changes. Future demand scenarios integrating these drivers over multi-decadal planning horizons are needed to develop effective adaptation strategies. This paper presents a new long-term scenario modeling framework that projects future daily municipal water demand at a 1/8° global spatial resolution. The methodology incorporates improved representations of important demand drivers such as urbanization and climate change. The framework is applied across multiple future socioeconomic and climate scenarios to explore municipal water demand uncertainties over the 21st century. The scenario analysis reveals that achieving a low-carbon development pathway can potentially reduce global municipal water demands in 2060 by 2–4%, although the timing and scale of impacts vary significantly with geographic location.     

A system dynamics model to support the management of artisanal dredge fisheries in the south coast of Portugal

This paper presents a management model developed to promote the sustainability of artisanal fisheries, considering socioeconomic and environmental dimensions. The management of artisanal fisheries faces many challenges, including the lack of appropriate tools to support policy makers and stakeholders in the decision‐making process. The model presented in this study is based on system dynamics and allows the simulation of the behavior of the artisanal dredge fishery on the south coast of Portugal, including four main species and two fleets. Two scenarios were simulated to assess the impact of regulatory measures on the system sustainability: scenario 1 simulated a permanent reduction of fishing effort, returning an improvement of biologic and economic sustainability; scenario 2 simulated the closure of one species for a period of one year to allow its recovery. It was found that although the revenue of fisheries decreases in that year, the system is able to return to the average levels of revenue three years after the closure. The study aimed to guide decision makers in the selection of the most appropriate measures toward the preservation of marine ecosystems and socioeconomic stability of fishing communities. The developed system dynamics model, combining available data with knowledge of fisheries experts, proved to be a useful scientific tool to identify management policies and organizational structures leading to greater success. This technique can be applied to the study of other fishery systems worldwide.     

Integrated torque vectoring and power management framework for electric vehicles

An integrated vehicle control framework is presented, which uses torque vectoring across independently driven wheels for control. The approach is general in nature, but is particularly well suited for electric vehicles due to increased control bandwidth. The novel algorithm optimizes wheel torque outputs in real time, constraining against power management, traction control, chassis configuration, actuator limits, and fault-case limitations. The structure is modular, and designed to adapt for differing vehicles with minimal re-tuning. Simulation and experimental results are provided for a modified electric SUV platform, under a range of dynamic maneuvers in 4WD, FWD, and RWD modes.     

基于系统动力学的对虾养殖品质风险应用

针对目前南美白对虾养殖环节存在的溯源点不清晰、养殖过程监管薄弱、品质评价不健全等品质风险问题,以 HACCP 为基准,结合国内外在养殖环节关键影响要素研究现状,对养殖环节建模,利用判断树的方法初选品质风险控制的关键控制点,然后结合 Vensim 软件建立南美白对虾养殖品质风险动力学模型,从而确定关键控制点的核心影响因素。仿真结果表明：南美白对虾养殖品质风险动力学模型能动态仿真五类影响要素对于幼虾品质和成活率的变化关系,从而反映品质风险动态变化情况。由此为南美白对虾溯源管理信息系统中溯源点的选取和养殖过程的实时监控和过程品质动态评价提供理论参考。     

基于横向调度的服务备件物流系统动力学模型与仿真

服务备件物流是一个复杂稳定的系统。从系统动力学的角度分析服务备件物流系统,建立了考虑横向调度和纵向紧急运输情况下,包含一个备件中心仓库和两个备件基层仓库组成的系统动力学模型,检验了其合理性。通过仿真得出以下结论：产品停产期前后,服务备件库存波动加剧,是备件库存管理的敏感期;产品生命周期越短、产品使用年限越长,服务备件库存波动越明显,其库存管理难度越大;各基层仓库服务对象越平均,其协作能力越强,服务备件中心仓库储存库存量越少。     

Selecting among five common modelling approaches for integrated environmental assessment and management

The design and implementation of effective environmental policies need to be informed by a holistic understanding of the system processes (biophysical, social and economic), their complex interactions, and how they respond to various changes. Models, integrating different system processes into a unified framework, are seen as useful tools to help analyse alternatives with stakeholders, assess their outcomes, and communicate results in a transparent way. This paper reviews five common approaches or model types that have the capacity to integrate knowledge by developing models that can accommodate multiple issues, values, scales and uncertainty considerations, as well as facilitate stakeholder engagement. The approaches considered are: systems dynamics, Bayesian networks, coupled component models, agent-based models and knowledge-based models (also referred to as expert systems). We start by discussing several considerations in model development, such as the purpose of model building, the availability of qualitative versus quantitative data for model specification, the level of spatio-temporal detail required, and treatment of uncertainty. These considerations and a review of applications are then used to develop a framework that aims to assist modellers and model users in the choice of an appropriate modelling approach for their integrated assessment applications and that enables more effective learning in interdisciplinary settings.     

综合导航显控台综合检测系统设计

综合导航显控台是船舶综合导航系统的核心导航设备,文章针对综合导航显控台设计了综合导航显控台综合检测系统,给出了综合检测系统的结构模型,在充分研究VxWorks操作系统的基础上提出了综合检测系统检测软件的功能设计与结构设计思路.本系统已经应用到实践,能够很好的完成对综合导航显控台的系统检测及故障点定位.     

基于智能优化控制的磨矿过程综合自动化系统

本文首先概述了磨矿的工艺过程和控制要求,然后从系统结构与功能、智能优化控制策略等方面详细描述了磨矿过程综合自动化系统,最后谈到该系统的实施及应用效果。     

一体化闸门自动测控系统设计

一体化闸门自动测控系统是针对小型闸站的现状及特点,研制的集信息采集、自动控制、通讯与网络、视频监视等功能为一体的新型设备。系统采用自主研发的开放式网络化信息控制平台,基于x86构架和工业现场总线技术,实现闸门自动控制功能的固化设计;采用SOFTPRO软件开发平台,可根据用户不同需求实现闸站控制系统的个性化定制。设计的一体化闸门自动测控系统能够适应闸站恶劣的运行环境,具有功能完备、可扩充性强、具有友好的人机界面、可靠性高、安装和维修方便、经济实用等优点,满足水资源监控与调度的需求。     

Hybrid modeling and simulation for complementing Lifecycle Assessment

This paper presents a new complementary lifecycle assessment (LCA) approach to address several limitations of the standard LCA methodology. An integrated approach of agent-based modeling, system dynamics and discrete event simulation was adopted to complement the standard LCA methodology. A hybrid simulation model was developed as a proof-of-concept system, then it was validated using a case study of bottled water and alternative drink products. The model was based on the assumption that parameters and relationships were constant regardless of local uniqueness. The research demonstrates that the hybrid modeling and simulation method can address several limitations of the standard LCA. Also, it is also proven that the method has a potential to address social and economic aspects.     

基于系统动力学模型的物元相关网研究

在可拓学相关分析理论中,关键在于确定相关基元的函数关系。然而,在具体领域中运用的时候,相关函数的确定往往是比较困难的,也就局限了相关网方法的使用。文章以物元为研究对象,对物元的相关网进行了研究,提出了相关网的动力学模型建模方法以及一种在相关函数未知的情况下,基于系统动力学模型的物元相关函数近似构造方法。该方法的原理是通过基础数据的收集和分析,在依据相关网建立的动力学模型中按照固定的步骤进行模拟分析,得出物元的近似相关函数。在此基础上,相关分析的进行就变得简单、可模拟。案例分析的结果表明,该方法能够有效模拟和近似构造相关物元之间的函数关系,为相关网方法在具体领域中的运用奠定了一定的基础。