一个实用的高速公路大气扩散模式

在高斯线源扩散模式的基础上，建立了一个适合高速公路大气污染源扩散特点的模式，并以沈阳环城高速公路环境影响评价中的应用为例，说明该模式的实用性和优越性．在建立该模式的过程中，应用了国外关于公路扩散试验的成果来确定和修正模式中的扩散参数．     

利用数学模式计算非离子氨浓度

根据我国颁布的《地面水环境质量标准非离子氨换算方法》，用Ｆｏｘｐｒｏ语言编程计算非离子氨浓度，提高监测数据处理率，减少计算误差．通过实例计算，程序运行正常，结果正确．     

工业生态系统的工业共生原理探讨

提出了共生单元，共生模式、共生环境构成工业共生的3要素。介绍了工业共生的质参量兼容原理，共生能量生成原理、系统进化原理。阐述了工业共生模式的4种类型：共栖，互利型工业共生。寄生型工业共生，附生型（异生型）工业共生，混合型工业共生。分析了工业共生的优势。     

多通管塑挤胀形关键技术的研究

多通管是工业上应用量大面广的一种基础件,但其传统的制造工艺目前还只限于铸造、焊接和机加工等,从经济或技术的角度讲都显得比较落后.此文讨论了利用聚氨酯橡胶棒为胀形介质,采用塑挤胀形的复合工艺把无缝管坯一次成形为成品的加工方法,分析了多通管塑挤胀形的过程,讨论了冲头作用于管坯的压力、聚氨酯橡胶棒产生的内压和平衡缸应提供的背压三者间应具备的合理的关系.以使变形区处于最有利于变形的强烈的三向压应力和合适的偏应力状态,获得尽可能长的支管.     

Determination and prediction of sediment yields from recession of the Holderness Coast, NE England

The rapidly eroding cliffs and foreshore of the Holderness Coast represent one of the largest sources of sediment discharging in the southern North Sea. For effective coastal management it is important to understand the sediment sources, transport pathways and depositional sinks. The sediment budget is regarded as one of the key information needs for sustainable planning and management. In order to quantify the sediment yield from recession of the Holderness Coast, digital photogrammetry has been used, together with nearshore bathymetric survey data, to produce a single DTM for a length of over 52 km of coastline. Other data including geological sections, sediment lithology, recession rates and the location of coastal defences have been added to the DTM to create a GIS for the Holderness Coast. The GIS has been used to predict the volume and nature of the sediment yield assuming that historical recession rates continue. The GIS can also be used to predict future yields using assumptions of accelerated recession or the implications of arrested retreat due to construction of defences.     

南岳森林群落生物多样性研究(Ⅵ)上封寺森林群落植物物种相对多度分布格局

本文应用几何级数分布、分割线段、对数级数分布和对数正态分布等4种模型研究了南岳上封寺森林群落植物物种相对多度的分布格局。结果表明,几何级数分布模型适宜拟合乔木层和草本层,而不适宜于灌木层;分割线段模型适宜于乔木层,其中,多度一频度模型还适于草本层;对数级数分布模型完全适宜于拟合任何层次;对数正态分布模型仅适宜于拟合乔木层。此外,α-指数值介于季雨林-稀树草原之间。     

Obtaining Environmental Favourability Functions from Logistic Regression

Logistic regression is a statistical tool widely used for predicting species’ potential distributions starting from presence/absence data and a set of independent variables. However, logistic regression equations compute probability values based not only on the values of the predictor variables but also on the relative proportion of presences and absences in the dataset, which does not adequately describe the environmental favourability for or against species presence. A few strategies have been used to circumvent this, but they usually imply an alteration of the original data or the discarding of potentially valuable information. We propose a way to obtain from logistic regression an environmental favourability function whose results are not affected by an uneven proportion of presences and absences. We tested the method on the distribution of virtual species in an imaginary territory. The favourability models yielded similar values regardless of the variation in the presence/absence ratio. We also illustrate with the example of the Pyrenean desman’s (Galemys pyrenaicus) distribution in Spain. The favourability model yielded more realistic potential distribution maps than the logistic regression model. Favourability values can be regarded as the degree of membership of the fuzzy set of sites whose environmental conditions are favourable to the species, which enables applying the rules of fuzzy logic to distribution modelling. They also allow for direct comparisons between models for species with different presence/absence ratios in the study area. This makes them more useful to estimate the conservation value of areas, to design ecological corridors, or to select appropriate areas for species reintroductions. Received: June 2005 / Revised: July 2005     

污水处理厂内毒物归宿模型的参数估计及应用

在建立城市污水处理厂毒物归宿模型的基础上，继续探讨了固液相吸附分配系数Ｋｐ，生物降解速率系数Ｋｂ，挥发及吹脱速率系数ＫｖＫｓｔ等模型参数的估计方法，并就模型的检验，模拟及其在风险评价中的应用作了案例研究。     

水质信息系统与水环境承载能力模式的研究

水环境承载能力是可持续发展理论的重要体现，它具有很强的动态、空间时空、水量水质兼顾、补偿等特性。建立水质信息系统基础平台，科学地利用和调控水环境承载能力，实现水环境保护目标。对水环境承载能力调控与水质信息系统模式的建立进行了研究分析，并结合我国实情提出了建模总体框架。     

Evaluation of the Community Multiscale Air Quality (CMAQ) model version 4.5: Sensitivities impacting model performance: Part I—Ozone

This study examines ozone (O₃) predictions from the Community Multiscale Air Quality (CMAQ) model version 4.5 and discusses potential factors influencing the model results. Daily maximum 8-h average O₃ levels are largely underpredicted when observed O₃ levels are above 85 ppb and overpredicted when they are below 35 ppb. Using a clustering approach, model performance was examined separately for several different synoptic regimes. Under the most common synoptic conditions of a typical summertime Bermuda High setup, the model showed good overall performance for O₃, while associations have been identified here between other, less frequent, synoptic regimes and the O₃ overprediction and underprediction biases. A sensitivity test between the CB-IV and CB05 chemical mechanisms showed that predictions of daily maximum 8-h average O₃ using CB05 were on average 7.3% higher than those using CB-IV. Boundary condition (BC) sensitivity tests show that the overprediction biases at low O₃ levels are more sensitive to the BC O₃ levels near the surface than BC concentrations aloft. These sensitivity tests also show the model performance for O₃ improved when using the global GEOS-CHEM BCs instead of default profiles. Simulations using the newest version of the CMAQ model (v4.6) showed a small improvement in O₃ predictions, particularly when vertical layers were not collapsed. Collectively, the results suggest that key synoptic weather patterns play a leading role in the prediction biases, and more detailed study of these episodes are needed to identify further modeling improvements.