烟气脱硝反应器计算流体力学模拟研究

SCR烟气脱硝系统中的流场与喷氨格栅设计,是影响系统主要技术指标的关键环节,采用计算流体动力学模拟方法建立计算模型,对某企业的锅炉烟气脱硝反应器进行模拟研究和工程设计,实践证明,该计算流体动力学模型能够满足烟气脱硝工程设计的精度要求,计算结果对工程设计具有较好的指导意义,对同类工程也具有一定的参考价值。     

旅游规划中的创意景观设计——以崇州市鸿乐仙境创意景观工程设计为例

出色的景观设计是乡村旅游规划中的重要产品之一.以崇州市鸿乐仙境创意景观工程设计为例,提出了一种基于环境要素体系的创意景观工程设计方法和程序.     

QuickBird影像融合最佳波段选择及不同融合方法质量评价研究

分析了QuickBird多光谱遥感影像各个波段的光谱特征,并进行了定量评价。根据信息量的大小和波段相关性得到最佳波段组合,在最佳组合波段下利用遥感影像处理软件ERDAS9.2选择或利用建模模块建立不同的影像融合模型对QuikBird多光谱数据与全色遥感影像进行融合,按照定性及定量指标对融合前后的遥感影像进行色彩、分辨率及信息量评价,得到QuikBird影像数据最佳融合方法。     

晋江垃圾焚烧发电综合处理厂工程实例

本文论述了晋江市垃圾焚烧发电综合处理厂的工程设计与建设的工艺特点。     

广东某城市污水处理厂CASS工艺设计

根据广东省某城市污水处理厂工程设计实例,介绍了该工程设计采用的比氏沉砂池的特点,以及CASS工艺设计参数的选用。     

工程设计资质标准

根据《建筑工程勘察设计管理条例》和《建设工程勘察设计资质管理规定》，建设部于2007年3月29日发布了《工程设计资质标准》（建市[2007]86号）。原《关于颁发工程勘察资质分级标准和工程设计资质分级标准的通知》（建设[2001]22号）中“工程设计资质分级标准”同时废止。其他有关规定与《工程设计资质标准》不符的，以该标准为准。《工程召研资质标准》现摘录如下：[编者按]     

基于信息量的ALI影像最佳波段选择及融合研究

分析了EO-1 ALI多光谱遥感影像各个波段的信息特征,根据信息量大小和波段间的相关性,联合偏度—峰度指数JSKF,提出针对ALI图像新的最佳波段组合方法。在最佳波段组合下对ALI多光谱数据与全色数据分别进行IHS、HPF、PCA和Wavelet变换融合,从信息量角度出发,按照定量指标对融合前后的遥感影像进行评价,并对融合前后影像进行分类应用。     

我国垃圾焚烧发电的发展前景

本文通过对垃圾处理方法的论述,阐明垃圾焚烧发电的可能性和必要性,并根据国外调研的资料及垃圾发电工程设计的经验,对我国垃圾焚烧发电厂建设提出了建议。     

基于PD的无阀滤池工程设计参数化系统

将参数化设计(PD)应用到无阀滤池工程设计参数化系统的开发中,分析了其参数化设计过程及其优点。通过参数化设计,将无阀滤池工程设计过程的效率提高了大约80%,同时设计过程更加人性化和智能化。     

某高速数据解调终端分系统的可靠性定量设计

可靠性与产品的其它特性一样,是工程设计的一项重要参数。电子行业的可靠性数据指出：设计原因是产品不可靠的最重要的原因。本文针对某高速数据解调终端分系统特别高的可靠性要求,分析了一种比较复杂的可靠性模型,并从理论上给出了完整的可靠性设计方法和预计结果,解决了困扰类似电子系统可靠性定量设计的问题。     

一种具有谐振特性的左手材料结构设计与仿真

文章提出了一种具有谐振特性的左手材料结构单元。该结构基于谐振型左手材料理论设计,使用CST电磁仿真软件,分析了该材料结构的谐振特性,并进一步提取出该材料的等效介电常数、等效磁导率和波矢量。结果表明,在4个结构单元条件下,该结构在X波段10.89-11.49GHz范围内出现由谐振特性产生的通带,其中在10.89-11.31GHz内出现右手传输通带以及在11.31-11.49GHz内出现谐振型左手通带。该结构的带通特性,或可在X波段范围内微波器件领域获得广泛应用。     

一种应用于双单元MIMO天线的电磁带隙结构设计与仿真

设计了一种应用于工作频率为2.6GHz的双单元多输入多输出（MIMO）天线的新型电磁带隙结构（EBG）。本文基于传统的蘑菇状结构,将贴片改进为螺旋状,调整偏移了过孔圆柱位置,并采用了电磁带隙结构单元的整体倒“T”形状布局。过孔的位置以及结构单元的间隔基于HFSS电磁仿真软件进行了优化,使新的结构在对天线系统传输特性影响很低的情况下更好的减小两个天线单元之间的耦合干扰。     

LAKE WATER QUALITY ASSESSMENT FROM LANDSAT THEMATIC MAPPER DATA USING NEURAL NETWORK: AN APPROACH TO OPTIMAL BAND COMBINATION SELECTION1

Abstract: The concern about water quality in inland water bodies such as lakes and reservoirs has been increasing. Owing to the complexity associated with field collection of water quality samples and subsequent laboratory analyses, scientists and researchers have employed remote sensing techniques for water quality information retrieval. Due to the limitations of linear regression methods, many researchers have employed the artificial neural network (ANN) technique to decorrelate satellite data in order to assess water quality. In this paper, we propose a method that establishes the output sensitivity toward changes in the individual input reflectance channels while modeling water quality from remote sensing data collected by Landsat thematic mapper (TM). From the sensitivity, a hypothesis about the importance of each band can be made and used as a guideline to select appropriate input variables (band combination) for ANN models based on the principle of parsimony for water quality retrieval. The approach is illustrated through a case study of Beaver Reservoir in Arkansas, USA. The results of the case study are highly promising and validate the input selection procedure outlined in this paper. The results indicate that this approach could significantly reduce the effort and computational time required to develop an ANN water quality model.     

宽带随机振动试验条件的加速因子

研究基于疲劳损伤等效的宽带随机振动试验条件的加速因子。首先回顾了基于窄带模型的随机振动试验条件的加速因子表达式,然后应用随机振动疲劳损伤的频域估计方法——基于窄带模型的修正方法（WL方法、α0.75方法和TB方法等）,得到了宽带随机振动试验条件加速因子计算的通用表达式。数值模拟分析表明,基于窄带模型的加速因子表达式对于比例载荷的宽带随机振动也是适用的,而对于非比例载荷,则需要应用文中提出的通用表达式才可以获得宽带随机振动的加速因子。     

Optimal power flow model incorporating wind,solar, and bundled solar-thermal power in the restructured Indian power system

A new optimal power flow model for wind, solar, and solar-thermal bundled power scheduling and dispatch is proposed, incorporating the deviation incentive/penalty charges for renewable energy introduced in India. The multiobjective function is solved using the flower pollination algorithm; the scheme is successfully tested on the IEEE 30-bus and Indian utility 30-bus systems. The forecasting error constraints introduced in renewable energy scheduling and dispatch are demonstrated to be beneficial in several aspects. Solar-thermal bundling is shown to create win-win situations for thermal and solar generators. The effectiveness of the flower pollination algorithm in solving optimal power flow models is proved.     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.