论模糊综合评判在水质污染评价中的应用

本文讨论了水质污染评价中,模糊变换■三种数学模型的应用问题。这三种数学模型为:■当在模糊变换中使用了权重向量(?)时,应选用数学模型3。本文最后讨论了综合评价目的向量■的应用问题。     

建设工程施工合同中两种付款方式的比较

被誉为“建筑业血脉”的工程款支付是整个建设工程合同的核心,是建设工程顺利实施的基础,是许多问题解决的根源所在,同时也是引发合同纠纷的主要原因之一。所以,在建设工程施工合同中有必要根据工程项目的具体情况选择合适的工程款支付方式,往往会起到事半功倍的效果。     

基于目标可靠度的公路土质边坡设计方法研究

综合考虑了工程与经济因素，以工程总费用现值作为可靠性优化的目标函数，建立公路土质边坡可靠性设计的优化模型，从而确定了公路土质边坡的目标可靠度推荐值，并给出了基于目标可靠度的公路土质边坡设计方法。     

基于时空马尔可夫随机场模型的车辆跟踪算法研究

鲁棒的车辆跟踪是实现交通事件自动检测的重要前提,车辆跟踪中的车辆相互遮挡则是影响车辆跟踪结果的关键因素。针对这一难题,设计自适应的车辆跟踪算法,并依据交通图像序列的时空相关性,根据马尔可夫的基本理论和贝叶斯方法,应用MRF-MAP理论分析框架,并结合了彩色图像序列的纹理信息建立了图像序列的时空马尔可夫随机场模型。采用随机松弛算法中的Metropolis算法来求解时空马尔可夫随机场模型,对车辆跟踪得到的目标标号图进行优化,从而解决车辆跟踪中的遮挡问题。初步实验结果,跟踪不遮挡的车辆时达到的跟踪成功率为95%。遮挡情况时成功率也可达到83%。实验结果表明,该跟踪算法在不遮挡时效果非常理想,在遮挡情况下跟踪鲁棒性也较好。     

车辙的成因及控制指标

介绍了车辙的种类，分析了发生车辙的原因，阐述了车辙控制指标的计算以及车辙深度的控制标准，从而为公路建设者提供理论指导。     

Quo vadis source tracking? Towards a strategic framework for environmental monitoring of fecal pollution

Advances in microbial source tracking (MST) have largely been driven by the need to comply with water quality standards based on traditional indicator bacteria. Recently, a number of culture-independent, and library-independent methods based on polymerase chain reaction (PCR) have been gaining popularity among source trackers. However, only a limited number of these methods have been successfully used in field applications, primarily due to the fact that many of them are still being developed. In this critical outlook, we examine different viewpoints associated with the practical use of MST to identify critical research gaps, propose a priority-based timeline to address them, and outline emerging technologies that will likely impact the future of source tracking. We propose that it is necessary to consider each of these aspects in order to advance towards a unifying framework in source identification, so that fecal pollution monitoring can be reliably used for comprehensive environmental microbial monitoring, to develop risk assessment models, and to implement and validate adequate management practices.     

试论房地产项目成本目标的管理

对项目成本目标的确定进行了介绍,从合理安排工程周期、控制建安成本、控制材料及设备价格、合理安排建设资金等方面对项目目标成本的控制进行了阐述,并对合理利用税收政策的筹划方面进行了论述,以达到提高企业经济效益的目的。     

面向对象的编程方法在土力学计算中的应用

介绍面向对象的思想，利用实例说明如何在土力学计算程序的编制过程中，运用数据抽象的方法建立土的计算模型，并提出编程语言的选择，保证了实现的可能性。     

Relationships between Bacteroides 16S rRNA genetic markers and presence of bacterial enteric pathogens and conventional fecal indicators

Occurrence and prevalence of different bacterial enteric pathogens as well as their relationships with conventional (total and fecal coliforms) and alternative fecal indicators (host-specific Bacteroides 16S rRNA genetic markers) were investigated for various water samples taken from different sites with different degrees of fecal contamination. The results showed that a wide range of bacterial pathogens could be detected in both municipal wastewater treatment plant samples and in surface water samples. Logistic regression analysis revealed that total and human-specific Bacteroides 16S rRNA genetic markers showed significant predictive values for the presence of Escheriachia coli O-157, Salmonella, heat-labile enterotoxin (LT) of enterotoxigenic E. coli (ETEC), and heat-stable enterotoxin for human (STh) of ETEC. The probability of occurrence of these pathogenic bacteria became significantly high when the concentrations of human-specific and total Bacteroides 16S rRNA genetic markers exceeded 10(3) and 10(4) copies/100 mL. In contrast, Clostridium perfringens was detected at high frequency regardless of sampling sites and levels of Bacteroides 16S rRNA genetic markers. No genes related to Shigella spp., Staphylococcus aureus and Vibrio cholerae were detected in any samples analyzed in this study. Conventional indicator microorganisms had low levels of correlation with the presence of pathogens as compared with the alternative fecal indicators. These results suggested that real-time PCR-based measurement of alternative Bacteroides 16S rRNA genetic markers was a rapid and sensitive tool to identify host-specific fecal pollution and probably associated bacterial pathogens. However, since one fecal indicator might not represent the relative abundance of all pathogenic bacteria, viruses and protozoa, combined application of alternative indicators with conventional ones could provide more comprehensive pictures of fecal contamination, its source and association with pathogenic microorganisms.     

结构优化设计在双排桩支护结构中的研究和应用

阐述了结构优化设计的基本原理和步骤;以双排桩工程造价为目标函数,以位移及抗弯强度等为约束条件,建立了双排桩支护结构的优化设计数学模型;通过编程计算,实现了此类结构的优化设计.算例分析表明,该优化设计方法经济效益显著,可供此类工程设计中参考应用.