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1.
Fault detection (FD) and diagnosis in industrial processes is essential to ensure process safety and maintain product quality. Partial least squares (PLS) has been used successfully in process monitoring because it can effectively deal with highly correlated process variables. However, the conventional PLS-based detection metrics, such as the Hotelling's T2 and the Q statistics are ill suited to detect small faults because they only use information from the most recent observations. Other univariate statistical monitoring methods, such as the exponentially weighted moving average (EWMA) control scheme, has shown better abilities to detect small faults. However, EWMA can only be used to monitor single variables. Therefore, the main objective of this paper is to combine the advantages of the univariate EWMA and PLS methods to enhance their performances and widen their applicability in practice. The performance of the proposed PLS-based EWMA FD method was compared with that of the conventional PLS FD method through two simulated examples, one using synthetic data and the other using simulated distillation column data. The simulation results clearly show the effectiveness of the proposed method over the conventional PLS, especially in the presence of faults with small magnitudes. 相似文献
2.
E. A. Snegin 《Russian Journal of Ecology》2005,36(1):33-40
The distribution pattern of the gastropod Bradybaena fruticum has been studied in a forest-steppe landscape. Analysis of the frequencies of polymorphic biochemical and conchological characters has yielded preliminary results on the characteristics of the species population structure whose formation was determined by a set of natural and anthropogenic factors.Translated from Ekologiya, No. 1, 2005, pp. 39–47.Original Russian Text Copyright © 2005 by Snegin. 相似文献
3.
赵玉萍 《环境监测管理与技术》2002,14(2):10-11
简述了小型餐饮服务业的特点,指出排污申报登记制度落实难、废水中各污染物排放量核定难及申报登记表设计欠合理是小型餐饮服务业在排污申报登记中存在的主要问题。提出,应加大宣传力度,进一步提高餐饮服务业业主以及广大公民的环保意识;制定较合理的排污量核算系数,修订申报内容;实行《排污申报登记注册证》制度,强化执法力度,以促进小型餐饮服务业全面实施排污申报登记制度。 相似文献
4.
5.
小型污水处理装置的应用与发展 总被引:11,自引:0,他引:11
简要论述了小型污水处理装置的作用,对目前市场上该类产品的应用现状进行了分析,并提出其发展方向。 相似文献
6.
WAHG Ren-zhong 《环境科学学报(英文版)》2002,14(1):20-26
Population demography, seed production, biomassallocation, net photosynthesis and transpiration of two Leymus chinensis divergence populations and between two years in Songnenplain, northeast China were compared. Strong differences betweenthe dry 1997 and moist 1998 occurred in vegetative shoot and sexualshoot densities, sexual differentiation and tiller densities, aswell as in the lengths of inflorescence, seed numbers perinflorescence, seed weights and biomass allocation in eachpopulation respectively (P<0.01). While strong differences betweenthe two populations occurred in vegetative shoot densities, sexualshoot densities, sexual differentiation and seed weights in eachyear (P<0.01). The differences between the two populations intiller densities and in biomass allocation to sexual shoots were significant (P<0.05). But there were no significant differences between the two populations in the lengths of inflorescence, seed numbers per inflorescence and biomass allocation to rhizomes and vegetative shoots (P>0.05). Excepting the transpiration rate in the early June, the differences between the two populations in net photosynthesis and transpiration rate of vegetative shoots and sexual shoots were strongly significant in the early June and July respectively (P<0.01). Relative stable variations in population demography and physiological traits between the two populations indicated that they are divergently in the Songnen Plain. 相似文献
7.
8.
The development and effective introduction of strategies designed to ensure the ecologically and economically sustainable utilization of coastal and marine resources is perhaps the major challenge for Small Island Developing States (SIDS). In response, the 1994 Barbados Programme of Action (BPoA) called upon the SIDS to implement appropriate coastal and marine strategies and, crucially, ensure that such strategies were integrated into sustainable national development plans (NDPs). This article examines the extent to which contemporary NDPs and donor support programmes have incorporated the fisheries sector — arguably the most important coastal/marine resource for many SIDS — into such documents. Applying an assessment methodology, originally developed to identify levels of environmental mainstreaming within World Bank country assistance strategies to NDPs and donor support programmes, we are able to identify those SIDS who have most effectively integrated the fisheries sector into such documents. Comparison with data indicating the importance of the sector to the national economy (in terms of generating foreign exchange, employment generation and/or supporting domestic protein consumption levels) enables us to pinpoint those countries with substantial fisheries sectors, but a correspondingly lower than expected degree of sectoral mainstreaming. We suggest that the January 2005 review of the BPoA offers an opportune moment for such countries to redress these omissions. 相似文献
9.
Doug P. Armstrong Elizabeth H. Parlato Barbara Egli Wendy J. Dimond Renske Kwikkel Åsa Berggren Mhairi McCready Kevin A. Parker John G. Ewen 《Conservation biology》2021,35(3):859-869
Inbreeding depression is an important long-term threat to reintroduced populations. However, the strength of inbreeding depression is difficult to estimate in wild populations because pedigree data are inevitably incomplete and because good data are needed on survival and reproduction. Predicting future population consequences is especially difficult because this also requires projecting future inbreeding levels and their impacts on long-term population dynamics, which are subject to many uncertainties. We illustrate how such projections can be derived through Bayesian state-space modeling methods based on a 26-year data set for North Island Robins (Petroica longipes) reintroduced to Tiritiri Matangi Island in 1992. We used pedigree data to model increases in the average inbreeding level (F ) over time based on kinship of possible breeding pairs and to estimate empirically Ne/N (effective/census population size). We used multiple imputation to model the unknown components of inbreeding coefficients, which allowed us to estimate effects of inbreeding on survival for all 1458 birds in the data set while modeling density dependence and environmental stochasticity. This modeling indicated that inbreeding reduced juvenile survival (1.83 lethal equivalents [SE 0.81]) and may have reduced subsequent adult survival (0.44 lethal equivalents [0.81]) but had no apparent effect on numbers of fledglings produced. Average inbreeding level increased to 0.10 (SE 0.001) as the population grew from 33 (0.3) to 160 (6) individuals over the 25 years, giving a ratio of 0.56 (0.01). Based on a model that also incorporated habitat regeneration, the population was projected to reach a maximum of 331–1144 birds (median 726) in 2130, then to begin a slow decline. Without inbreeding, the population would be expected stabilize at 887–1465 birds (median 1131). Such analysis, therefore, makes it possible to empirically derive the information needed for rational decisions about inbreeding management while accounting for multiple sources of uncertainty. 相似文献
10.
Local rural and indigenous communities have assumed increasing responsibility for conservation within and between areas buffering the impacts of agricultural or resource‐extraction zones and protected areas. Empowering local communities as central partners in conservation and climate‐change mitigation has allowed many people to gain access to land and citizenship rights but has provided limited improvements in access to social services and economic opportunities even as expectation about their role as environmental stewards grows. These expectations, however, are inconsistent with reality. We conducted multiple field studies in Brazil since the mid‐1980s to illustrate the discrepancies between conservation programs and local conditions and expectations. We suggest that public policies and conservation programs should not delegate responsibility for managing protected areas to local and indigenous communities without considering local needs and expectations and locals’ attitudes toward conservation. In other words, behavior that maintains or improves the environment should not be treated as traditional based on the expectations of outsiders. Framing local populations as traditional environmentalists creates contradictions and frustrations for local populations and for conservation professionals and policy makers. 相似文献