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151.
W. M. Snyder 《Journal of the American Water Resources Association》1980,16(1):22-30
ABSTRACT: Sliding polynomials differ from other piecewise interpolation and smoothing methods in their functional continuity at the nodes. This functional continuity was used to establish optional spacing of nodes and optional boundary controls in data smoothing while still maintaining mathematically continuous rates or gradients. Cyclic as well as noncyclic data can be smoothed. Variance of the individual nodal values. derived through least-squares optimization, can be calculated using the rigorously determined weighting coefficients between data points and nodes. Such nodal variances are estimates of localized uncertainty in the data which complement the localization of smoothing through use of piecewise functions. Choice of controls in smoothing and calculation of variance have been incorporated in a computer program for user convenience. 相似文献
152.
A Multi-Channel Continuous Water Toxicity Monitoring System: Its Evaluation and Application to Water Discharged from a Power Plant 总被引:2,自引:0,他引:2
A multi-channel continuous water toxicity monitoring system was, after confirming the systems' performance, implemented to
samples of water discharged from power plants to detect and classify their toxicity using several recombinant bioluminescent
bacteria. Each channel of the system is composed of a series of two mini-bioreactors to enable a continuous operation, i.e.,
without system interruption due to highly toxic samples. A different recombinant bacterial strain was present in each channel:
DPD2540 (fabA::lux CDABE), DPD2794 (recA::luxCDABE), and TV1061 (grpE::luxCDABE), which are induced by cell membrane-, DNA-, and protein-damaging agents, respectively. GC2 (lac::luxCDABE) is a constitutive strain, whose bioluminescence is reduced by an increase in cellular toxicity. Phenol and mitomycin C (MMC)
were used for evaluating the system's performance to detect toxic chemicals. These samples were injected into the second mini-bioreactor
according to a step or bell-curve manner. The field samples used in this study were obtained from the water discharged from
two different power plants in Korea – from a nuclear power plant and a thermo-electronic power plant, and were injected into
the second mini-bioreactor to initiate the toxicity test. Each channel showed specific bioluminescent (BL) response profiles
due to the toxic compounds present in the water samples. Comparing the BL signals between the standard toxic chemical samples
and discharged water samples, the equivalent toxicity of the field water could be estimated. Finally, it was proved that this
novel continuous toxicity monitoring system can be used as an alternative tool for the quick monitoring and control of water
quality, as well as aid in the setting up of a new monitoring strategy to protect the source of tap water and in the prevention
of polluted water discharge. 相似文献
153.
154.
Tedesco M Bohlen WF Howard-Strobel MM Cohen DR Tebeau PA 《Environmental monitoring and assessment》2003,81(1-3):35-42
A network of five water quality monitoring stations has been established in Long Island Sound, measuring temperature, salinity, and dissolved oxygen since 1999. The stations are located in areas of extreme water quality degradation (western Long Island Sound) as well as in pristine areas (eastern Long Island Sound). The data from these stations are collected every 15 minutes and posted to the project web site in real time as provisional data. After subsequent quality assurance procedures, the data are archived to the project File Transfer Protocol (FSP) site for downloading by the user community. The network of stations is in part supported logistically by a number of partners, including state and local agencies, schools, and non-governmental organizations. Data from the monitoring programs of some of these partners are also published to the project website providing a more comprehensive and complete picture of the status of the Sound than can be provided independently. This repository of information is used by marine educators, resource managers, scientists, and the general public, each with a different end purpose. We use the data from two of the stations to show that these high frequency time series measurements can be used to complement and enhance other monitoring programs within the Sound, documenting in greater detail the occurrence and duration of hypoxic events. 相似文献
155.
连续流动分析在水质监测中的应用 总被引:6,自引:0,他引:6
连续流动分析技术具有分析速度快、准确度和精密度高、操作简单、通用性强、样品和试剂消耗量少等一系列优点。灵活运用连续流动分析技术可对大多数水性样品如水和废水、土壤(或固体废弃物)提取液、饮料等进行分析。本文中着重介绍了氨氮、硝酸盐氮/亚硝酸盐氮、挥发酚以及总氰化物等几个连续流动分析在水质监测中的应用实例。 相似文献
156.
王彤 《辽宁城乡环境科技》2005,25(5):9-10,56
在分析辽宁省生活垃圾产生量逐年增加、组份日益复杂、生活垃圾混合收集,处理设施建设滞后等现状及问题的基础上,提出了“十一五”期间要树立“垃圾是放错位置的资源”的概念,以“减量化、无害化、资源化”为原则,通过实施循环经济,将垃圾最大化利用,同时进一步提出了“十一五”期间辽宁省生活垃圾污染防治的管理与工程对策。 相似文献
157.
2003年陕西持续性暴雨成因分析 总被引:13,自引:8,他引:13
对2003年发生在陕西的持续性暴雨分析认为: 乌山阻高与副热带高压的配置及稳定少动为这次持续性暴雨提供了有利的背景条件.贝湖低压底部分裂出小槽引导的冷空气与副高西北侧暖湿气流在高原东侧一带反复交绥是暴雨的主要成因.高低空急流耦合使高层辐散区迭加在低层辐合区的上方而产生强烈的上升运动,为深对流的发展提供了条件,促进了暴雨时中尺度系统的生成和维持. 相似文献
158.
以研究业务持续管理相关的国际法规条款与PDCA持续改善架构,给出业务持续管理关键要素定义以其在PDCA架构中所担任的角色与位阶,进而制定企业业务持续管理的PDCA封闭式管理模型,并阐述企业典型业务持续管理各个要素的实行重点,为企业的业务风险管理提供可用的方法与可执行的建议。 相似文献
159.
采用有限元方法对三跨连续钢筋混凝土板局部受火和整体受火下的结构响应进行了数值模拟。结果表明,结构受火位置和受火范围不同时,产生的塑性区位置和范围不同,出现破坏铰的位置不同,但是经过模拟发现塑性区域都是在中间支座附近,破坏铰都是在负筋截断形成,因此结构的负筋长度对结构的耐火性能影响很大;结构在整体受火情况下由于整个结构绕塑性区的抬升作用,造成塑性区附近中跨的抬升,加温结束后整个中跨呈隆起形式,但是中跨局部受火时其中点始终产生向下的挠度,因此在局部受火与整体受火时结构的整体变形不同;在局部受火的时候,由于结构的整体作用使受火跨和未受火跨之间有很大程度的内力调整,这种内力重分布可以很好地提高结构的抗火性能,结构在局部受火的时候耐火性能比整体受火时好出很多。 相似文献
160.