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91.
“水蚯蚓-微生物共生系统”细观机理模型(T-FCASM)建立及校验 总被引:2,自引:2,他引:0
基于浙江省诸暨市菲达宏宇污水处理厂新型氧化沟工艺的现场长期观察和试验研究,提出“水蚯蚓-微生物共生系统”的新技术原理,获得了“水蚯蚓-微生物共生系统”中污染物输入量与输出量随时间的动态变化规律,并建立了水蚯蚓作用的传递函数,从而实现水蚯蚓在污水处理和污泥降解过程中对污染物去除作用的模拟.以全耦合活性污泥模型(FCASM3)为基础平台,结合水蚯蚓作用的传递函数,最终建立了污水厂“水蚯蚓-微生物共生系统”细观机理模型(T-FCASM).利用对该污水处理厂常规水质指标测定和进水模型组分分析等试验结果,完成了对“水蚯蚓-微生物共生系统”细观机理模型(T-FCASM)的校验工作.动态模拟结果表明:T-FCASM实现了对回流污泥浓度的准确模拟;同时该模型能够对污水处理厂生物去除有机物及脱氮过程进行较准确的模拟,而对生物除磷过程的模拟,由于该污水处理厂低磷进水的原因,与实测值存在一定的偏差. 相似文献
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Coral reefs are highly dynamic and productive marine ecosystems, providing habitat and refuge for an enormous number of species
including fish, invertebrates and algae. With increased anthropogenic pressures and global climate change, many coral reefs
are rapidly declining. Currently, there is limited knowledge on condition and community assemblage composition of shallow
fringing coral reefs along the south-eastern coast of Queensland, Australia. With increased demand to determine existence
of coastal fringing reefs by National Regional Management groups, a rapid cost effective method to determine reef composition
and condition was required. The aim of this study was to determine the benthic structure and extent of two small coastal fringing
reefs (Hummock Hill Reef and Stringers Reef) along the Southern Great Barrier Reef. Reef substrate assessments were carried
out using a rapid assessment technique and a Point Intercept Method (PIM). The data were analysed and classified using a Geographic
Information System (GIS). Percent substrate cover was calculated using a visual basic image analysis program. The Point intercept
method showed higher accuracy over the rapid assessment technique (up to 15–40% difference) and was thus deemed a more suitable
classification tool for reefs with high structural complexity and heterogeneity. This study focused on piloting a rapid, cost
effective Point Intercept Technique using random point count methodology to document coral benthic habitat and extent over
a commonly used rapid assessment method as a tool for reef coastal management and conservation. The two techniques were compared
and substrate classification success, limitations and errors were discussed. 相似文献
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96.
External drift kriging of NOx concentrations with dispersion model output in a reduced air quality monitoring network 总被引:1,自引:0,他引:1
Jan van de Kassteele Alfred Stein Arnold L. M. Dekkers Guus J. M. Velders 《Environmental and Ecological Statistics》2009,16(3):321-339
In the mid nineteen eighties the Dutch NOx air quality monitoring network was reduced from 73 to 32 rural and city background stations, leading to higher spatial uncertainties.
In this study, several other sources of information are being used to help reduce uncertainties in parameter estimation and
spatial mapping. For parameter estimation, we used Bayesian inference. For mapping, we used kriging with external drift (KED)
including secondary information from a dispersion model. The methods were applied to atmospheric NOx concentrations on rural and urban scales. We compared Bayesian estimation with restricted maximum likelihood estimation and
KED with universal kriging. As a reference we also included ordinary least squares (OLS). Comparison of several parameter
estimation and spatial interpolation methods was done by cross-validation. Bayesian analysis resulted in an error reduction
of 10 to 20% as compared to restricted maximum likelihood, whereas KED resulted in an error reduction of 50% as compared to
universal kriging. Where observations were sparse, the predictions were substantially improved by inclusion of the dispersion
model output and by using available prior information. No major improvement was observed as compared to OLS, the cause presumably
being that much good information is contained in the dispersion model output, so that no additional spatial residual random
field is required to explain the data. In all, we conclude that reduction in the monitoring network could be compensated by
modern geostatistical methods, and that a traditional simple statistical model is of an almost equal quality.
相似文献
Jan van de KassteeleEmail: |
97.
Validation of MODIS aerosol retrievals and evaluation of potential cloud contamination in East Asia 总被引:10,自引:0,他引:10
MODIS aerosol retrievals onboard Terra/Aqua and ground truth data obtained from AERONET(Aerosol Robtic Network) solar direct radiance measurements are collocated to evaluate the quality of the former in East Asia. AERONET stations in East Asia are separated into two groups according to their locations and the preliminary validation results for each station. The validation results showed that the accuracy of MODIS aerosol retrievals in East Asia is a little worse than that obtained in other regions such as Eastern U.S., Western Europe, Brazil and so on. The primary reason is due to the improper aerosol model used in MODIS aerosol retrieval algorithm, so it is of significance to characterize aerosol properties properly according to long term ground-based remote sensing or other relevant in situ observations in order to improve MODIS retrievals in East Asia. Cloud contamination is proved to be one of large errors, which is demonstrated by the significant relation between MODIS aerosol retrievals versus cloud fraction, as well as notable improvement of linear relation between satellite and ground aerosol data after potential cloud contamination screened. Hence, it is suggested that more stringent clear sky condition be set in use of MODIS aerosol data. It should be pointed out that the improvement might be offset by other error sources in some cases because of complex relation between different errors. Large seasonal variation of surface reflection and uncertainties associated with it result in large intercepts and random error in MODIS aerosol retrievals in northern inland of East Asia. It remains to be a big problem to retrieve aerosols accurately in inland characterized by relatively larger surface reflection than the requirement in MODIS aerosol retrieval algorithm. 相似文献
98.
Thriving is defined as the psychological state in which individuals experience both a sense of vitality and learning. We developed and validated a measure of the construct of thriving at work. Additionally, we theoretically refined the construct by linking it to key outcomes, such as job performance, and by examining its contextual embeddedness. In Study 1, we conducted second‐order confirmatory factor analyses in two samples, demonstrating initial support for the two‐dimensional structure of thriving. We provided evidence for the convergent and discriminant validity of thriving in relation to theoretically related constructs, such as positive and negative affects, learning and performance goal orientations, proactive personality, and core self‐evaluations. In Study 2, across two different samples, we further assessed construct validity by establishing a relationship between thriving and career development initiative, burnout, health, and individual job performance, explaining significant variance beyond traditional attitudinal predictors, such as job satisfaction and organizational commitment. Finally, in Study 3, we focused on understanding the contextual embeddedness of thriving. We found differences in reports of thriving across two points in time, when substantial changes are occurring in peoples' work lives and across contexts (i.e., work and non‐work). Implications for theory and practice, as well as directions for future research, are discussed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
99.
依据现有指南和规范,在分析方法标准验证实验和报告中,常常分别评估准确度和精密度。这容易导致以加标回收率表示的准确度数据缺乏良好精密度支持的现象。基于ISO 11352原理,首次提出在不增加实验室分析人员工作量的情况下,利用自上而下技术评估方法测量不确定度,即同时考虑准确度与精密度作为一个综合性指标评估方法性能。这是标准制修订时落实测量不确定度条文一条操作性强的技术路线。利用改进后的加标回收率计算结果评估方法准确度。5组方法验证实测数据表明,用测量不确定度这一综合性指标评估方法性能比分别用准确度和精密度指标更符合实际情况。他可引导实验室分析人员在设计和处理方法验证数据时,更加重视方法精密度。在修订HJ 168—2010时,建议增加测量不确定度这一综合性指标评估方法性能。 相似文献
100.