A CyberGIS Integration and Computation Framework for High‐Resolution Continental‐Scale Flood Inundation Mapping

We present a Digital Elevation Model‐based hydrologic analysis methodology for continental flood inundation mapping (CFIM), implemented as a cyberGIS scientific workflow in which a 1/3rd arc‐second (10 m) height above nearest drainage (HAND) raster data for the conterminous United States (CONUS) was computed and employed for subsequent inundation mapping. A cyberGIS framework was developed to enable spatiotemporal integration and scalable computing of the entire inundation mapping process on a hybrid supercomputing architecture. The first 1/3rd arc‐second CONUS HAND raster dataset was computed in 1.5 days on the cyberGIS Resourcing Open Geospatial Education and Research supercomputer. The inundation mapping process developed in our exploratory study couples HAND with National Water Model forecast data to enable near real‐time inundation forecasts for CONUS. The computational performance of HAND and the inundation mapping process were profiled to gain insights into the computational characteristics in high‐performance parallel computing scenarios. The establishment of the CFIM computational framework has broad and significant research implications that may lead to further development and improvement of flood inundation mapping methodologies.     

取样及样品前处理对制革废水中总铬的影响

通过利用火焰原子吸收分光光度法测定制革企业不同工艺流程产生废水的总铬,考察不同量具及取样量、不同消解方法和样品保存期限对测定结果的影响。结果表明水样中悬浮物造成的取样不均匀性导致测定结果差异明显,不同消解方法测定制革废水总铬,检测数据具有可比性,固定剂的加入能够使得水样检测数据保持稳定。     

土地人口承载力计算方法综述

随着人们对土地人口承载力的日益关注,国内外涌现出大量关于土地人口承载力的研究方法。文章将土地人口承载力的计算方法归纳为两大类：生产潜力推算法和直接计算法,并进一步总结了包含在这两大类中的多种计算方法;通过图表的方式比较分析了这些方法的适用范围、优点及局限性;指出了当前土地人口承载力研究中存在的一些问题;对其今后研究的发展趋势做了进一步的展望,最后,提出了深化研究的几点建议,即加强土地人口承载力的过程研究、预警研究、多因子要素研究和各类型区研究。     

关于中国在用汽车排污控制的若干问题--柴油车部分

文章结合《点燃式发动机汽车排气污染物排放限值及测量方法（双怠速法及简易工况法）》（GB18285—2005）修订中的重大问题阐述中国在用汽油车排气烟度控制方面的新要求。主要包括：增加高怠速排污检测、对电喷汽车增加过量空气系数（λ）的限定、新规定了国1以来的在用汽油车双怠速排放限值、双燃料车要对两种燃料分别检测、对简易工况检测法作了规定、制定简易工况检测法排放限值的基本原则和方法、供地方参考的排放限值等。     

浅谈室内环境污染问题

介绍中国室内环境污染问题的现状、治理室内环境污染的法律依据和室内空气质量标准,阐述了室内环境中的主要污染物(甲醛、苯、挥发性有机化合物等)对人体健康产生的危害,分析了室内环境污染物的主要来源,并从增强人们的环保意识、防止室内环境污染、正确理解环保产品等方面提出了建议和对策,归纳了室内环境污染后的治理方法和治理效果,其中治理方法包括感觉脱臭法、化学反应法、吸附法和生物法。这对提高人们认识室内环境污染对人体健康的影响以及降低污染所造成的危害具有重要意义。     

Numerical Simulation of Interaction of the Heavy Gas Cloud with the Atmospheric Surface Layer

The numerical time-dependent three-dimensional model [Kovalets, I.V. and Maderich, V.S.: 2001, Int. J. Fluid Mech. Res. 30, 410–429] of the heavy gas dispersion in the atmospheric boundary layer has been improved by parameterizing momentum and heat fluxes on the surface of Earth using Monin–Obukhov similarity theory. Three parameterizations of heat exchange with the surface of Earth were considered: (A) formula of Yaglom A.M. and Kader B.A. [1974, J. Fluid Mech. 62, 601–623] for forced convection, (B) interpolation formula for mixed convection and (C) similarity relationship for mixed convection [Kader, B.A. and Yaglom, A.M.: 1990, J. Fluid Mech. 212, 637–662]. Two case studies were considered. In the first study based on experiment of Zhu et al., J. Hazard Mater 62, 161–186], the interaction of an isothermal heavy gas plume with an atmospheric surface layer was simulated. It was found that stable stratification in the cloud essentially suppresses the turbulence in the plume, reducing the turbulent momentum flux by a factor of down to 1/5 in comparison with the undisturbed value. This reduction essentially influences velocities in the atmospheric boundary layer above the cloud, increasing the mean velocity by a factor of up to 1.3 in comparison with the undisturbed value. A simulation of cold heavy gas dispersion was carried out in the second case based on field experiment BURRO 8. It was shown that both forced and free convections under moderate wind speeds significantly influence the plume. The relative rms and bias errors of prediction the plume’s height were σ_H ≈ 30% and ɛ_H = − 10%, respectively, for parameterization B, while for A and C the errors were σ_H ≈ 80% and ɛ_H ≈ − 65%. It is therefore advised to use the simple parameterization B in dense gas dispersion models.     

Solving multidimensional bioeconomic problems with singular-perturbation reduction methods: Application to managing pest resistance to pesticidal crops

We investigate the application of ‘singular-perturbation’ reduction methods from the dynamical-systems literature to solve continuous-time multidimensional bioeconomic models resulting from integrating economics with increasingly complex biological structures. These methods reduce multidimensional solution space to the lower-dimensional subspace confining long-term dynamics. They arise naturally in problems with state variables evolving on widely disparate time scales. In particular, we demonstrate how the methods reduce the solution space of a linear-control specification—characterized by two state variables adjusting at widely disparate rates—to a single differential equation in the slow variable. All other system variables are determined by algebraic equations. We apply singular-perturbation methods to investigate the optimal management of pest resistance to pesticidal crops. The pest population evolves on a fast-time scale, while the population's genetic composition evolves on a slow-time scale. In comparison with past work, we can more fully characterize the continuous-time dynamics associated with a complex genetic specification.     

危险化学品泄漏入海区域风险评估方法研究

我国的危险化学品区域风险评估研究工作起步较晚,针对危险化学品泄漏入海的方法研究较少。现有区域风险评估方法中评估对象多为单一风险因素,存在着未全面考虑研究区域内其他风险源和敏感资源等综合影响的不足。在结合国内外研究进展现状的基础上,强化与相关技术方法的衔接,建立了综合考虑危险化学品危险性和区域风险承受力等因素的危险化学品泄漏入海区域风险评估方法工作,并选择天津市XX企业开展方法案例应用。本研究能够为科学合理划分危险化学品泄漏区域海洋环境风险等级提供技术支撑,为开展危险化学品泄漏入海风险防范和修复评估等工作提供决策依据。