Inside the whale: the structure and dynamics of the isolated Cetus dwarf spheroidal     

G. F. Lewis  R. A. Ibata  S. C. Chapman  A. McConnachie  M. J. Irwin  E. Tolstoy  N. R. Tanvir 《Monthly notices of the Royal Astronomical Society》2007,375(4):1364-1370

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Heterogeneous data management and modeling for the gravimetric geoid model: a review study in Pakistan     

Sadiq  Muhammad  Ahmad  Zulfiqar 《Arabian Journal of Geosciences》2015,8(4):2247-2263

Arabian Journal of Geosciences - The gravimetric geoid model can be used as vertical reference in surveying and other related technologies. It is being developed by NESCOM in collaboration with the...  相似文献   

Evaluating water reuse applications under uncertainty: generalized intuitionistic fuzzy-based approach     

Qian?PanEmail author  Gyan?Chhipi-Shrestha  Deyun?Zhou  Kun?Zhang  Kasun?Hewage  Rehan?Sadiq 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(4):1099-1111

Water reuse is a viable option to increase urban water supply, especially under new realities of climate change and increasing anthropogenic activities. A sustainable water reuse application should be cost-effective and have acceptable health risk to consumers. Water reuse application evaluation is complex because data acquisitions are usually associated with the problems of uncertainty, hesitancy, and parameterization. In this paper, a generalized intuitionistic fuzzy soft set (GIFSS)-based decision support framework is proposed to provide an effective approach to describe uncertainty and hesitancy in an intuitionistic fuzzy number. In addition, the modified measures of comparison and similarity are proposed to compare water reuse applications. Then, the proposed framework is applied to the City of Penticton (British Columbia, Canada) to evaluate seven water reuse applications. The evaluation results show that the applications of garden flower watering and public parks watering are the most preferred alternatives, which are consistent with the existing practice in the city. Furthermore, the results are highly affected by the generalized parameter and the weights of evaluation criteria. Both the comparison measure-based and similarity measure-based evaluations within the same GIFSS-based framework produce consistent results, indicating an applicable and efficient methodology.  相似文献   

Impacts of Water Quality on the Spatiotemporal Susceptibility of Water Distribution Systems     

Md Maruf Mortula  Tarig A. Ali  Rehan Sadiq  AlaEldin Idris  Asam Al Mulla 《洁净——土壤、空气、水》2019,47(5)

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Synergies of THESEUS with the large facilities of the 2030s and guest observer opportunities     

Rosati  P.  Basa  S.  Blain  A. W.  Bozzo  E.  Branchesi  M.  Christensen  L.  Ferrara  A.  Gomboc  A.  O’Brien  P. T.  Osborne  J. P.  Rossi  A.  Schüssler  F.  Spurio  M.  Stergioulas  N.  Stratta  G.  Amati  L.  Casewell  S.  Ciolfi  R.  Ghirlanda  G.  Grimm  S.  Guetta  D.  Harms  J.  Le Floc’h  E.  Longo  F.  Maggiore  M.  Mereghetti  S.  Oganesyan  G.  Salvaterra  R.  Tanvir  N. R.  Turriziani  S.  Vergani  S. D.  Balman  S.  Caruana  J.  Erkut  M. H.  Guidorzi  G.  Frontera  F.  Martin-Carrillo  A.  Paltani  S.  Porquet  D.  Sergijenko  O. 《Experimental Astronomy》2021,52(3):407-437

Experimental Astronomy - The proposed THESEUS mission will vastly expand the capabilities to monitor the high-energy sky. It will specifically exploit large samples of gamma-ray bursts to probe the...  相似文献   

Investigating evidential reasoning for the interpretation of microbial water quality in a distribution network   总被引：1，自引：1，他引：1  

Rehan Sadiq  Homayoun Najjaran  Yehuda Kleiner 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,21(1):63-73

Total coliforms are used as indicators for evaluating microbial water quality in distribution networks. However, total coliform provides only a weak “evidence” of possible fecal contamination because pathogens are subset of total coliform and therefore their presence in drinking water is not necessarily associated with fecal contamination. Heterotrophic plate counts are also commonly used to evaluate microbial water quality in the distribution networks, but they cover even a wider range of organisms. As a result, both of these indicators can provide incomplete and highly uncertain bodies of evidence when used individually. In this paper, it is shown that combing these two sources of information by an appropriate data fusion technique can provide improved insight into microbial water quality within distribution networks. Approximate reasoning methods like fuzzy logic and probabilistic reasoning are commonly used for data fusion where knowledge is uncertain (i.e., ambiguous, incomplete, and/or vague). Traditional probabilistic frameworks like Bayesian analysis, reasons through conditioning based on prior probabilities (which are hardly ever available). The Dempster–Shafer (DS) theory generalizes the Bayesian analysis without requiring prior probabilities. The DS theory can efficiently deal with the difficulties related to the interpretation of overall water quality where the redundancy of information is routinely observed and the credibility of available data continuously changes. In this paper, the DS rule of combination and its modifications including Yager’s modified rule, Dubois–Prade disjunctive rule and Dezert–Smarandache rule are described using an example of microbial water quality in a distribution network.  相似文献   

Risk-based environmental decision-making using fuzzy analytic hierarchy process (F-AHP)   总被引：1，自引：4，他引：1  

Solomon Tesfamariam  Rehan Sadiq 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,21(1):35-50

Environmental risk management is an integral part of risk analyses. The selection of different mitigating or preventive alternatives often involve competing and conflicting criteria, which requires sophisticated multi-criteria decision-making (MCDM) methods. Analytic hierarchy process (AHP) is one of the most commonly used MCDM methods, which integrates subjective and personal preferences in performing analyses. AHP works on a premise that decision-making of complex problems can be handled by structuring the complex problem into a simple and comprehensible hierarchical structure. However, AHP involves human subjectivity, which introduces vagueness type uncertainty and necessitates the use of decision-making under uncertainty. In this paper, vagueness type uncertainty is considered using fuzzy-based techniques. The traditional AHP is modified to fuzzy AHP using fuzzy arithmetic operations. The concept of risk attitude and associated confidence of a decision maker on the estimates of pairwise comparisons are also discussed. The methodology of the proposed technique is built on a hypothetical example and its efficacy is demonstrated through an application dealing with the selection of drilling fluid/mud for offshore oil and gas operations.  相似文献   

The early- and late-time spectral and temporal evolution of GRB 050716     

E. Rol  J. P. Osborne  K. L. Page  K. E. McGowan  A. P. Beardmore  P. T. O'Brien  A. J. Levan  D. Bersier  C. Guidorzi  F. Marshall  A. S. Fruchter  N. R. Tanvir  A. Monfardini  A. Gomboc  S. Barthelmy  N. P. Bannister 《Monthly notices of the Royal Astronomical Society》2007,374(3):1078-1084

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Life cycle greenhouse gas footprint of shale gas: a probabilistic approach   总被引：1，自引：1，他引：0  

Anjuman Shahriar  Rehan Sadiq  Solomon Tesfamariam 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(8):2185-2204

With the increase in natural gas (NG) production in recent years, primarily from shale gas, some sources, including the US Environmental Protection Agency (EPA), have suggested that upstream methane emissions are increasing. Much of the recent controversy has centered on emissions during well drilling, testing, and completion even though emissions downstream of the wellhead are also of concern. The study critically assessed the current state of knowledge about the life cycle GHG footprint of NG, analyzed the assumptions, data and analysis methodologies used in the existing literature. This study comprehensively analyzed the emission of methane from different stage of the life of well for conventional and unconventional NG using the EPA’s revised 2011 estimates as well as other existing literature and publicly available government data. The study proposed a probabilistic model to estimate the range of total GHG footprint of NG with varying probabilities. Through the bottom up approach starting from the well construction to the delivery of NG to the small user and using Monte Carlo simulation, the study identified the critical sources of fugitive emissions from the NG. As expected, emissions from well completion and periodic emissions (e.g. liquid unloading in the case of onshore conventional wells and workovers in the case of unconventional wells) are significant contributors to the overall GHG footprint of NG, and possess large opportunity for reduction. Finally the application of probabilistic model is demonstrated through a case study using the data from the Montney and Horn River shale gas basins in the Northern British Columbia to estimate the range of total GHG footprint of shale gas with varying probabilities. The study found that the GHG footprint of Montney and Horn River wells are much smaller than that of Barnett shale (which is representative of US shale gas) due to strict flaring regulations followed in BC. The study also undercuts the outcome of Howarth et al. (Clim Chang Lett 106:679–690, 2011), which states that the GHG footprint of shale gas is at least 20 % greater than coal.  相似文献   

Seasonal ensemble generator for radar rainfall using copula and autoregressive model     

Qiang Dai  Dawei Han  Lu Zhuo  Jun Zhang  Tanvir Islam  Prashant K. Srivastava 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(1):27-38

Uncertainty analysis of radar rainfall enables stakeholders and users have a clear knowledge of the possible uncertainty associated with the rainfall products. Long-term empirical modeling of the relationship between radar and gauge measurements is an efficient and practical method to describe the radar rainfall uncertainty. However, complicated variation of synoptic conditions makes the radar-rainfall uncertainty model based on historical data hard to extend in the future state. A promising solution is to integrate synoptic regimes with the empirical model and explore the impact of individual synoptic regimes on radar rainfall uncertainty. This study is an attempt to introduce season, one of the most important synoptic factor, into the radar rainfall uncertainty model and proposes a seasonal ensemble generator for radar rainfall using copula and autoregressive model. We firstly analyze the histograms of rainfall-weighted temperature, the radar-gauge relationships, and Box and Whisker plots in different seasons and conclude that the radar rainfall uncertainty has strong seasonal dependence. Then a seasonal ensemble generator is designed and implemented in a UK catchment under a temperate maritime climate, which can fully model marginal distribution, spatial dependence, temporal dependence and seasonal dependence of radar rainfall uncertainty. To test its performance, 12 typical rainfall events (4 for each season) are chosen to generate ensemble rainfall values. In each time step, 500 ensemble members are produced and the values of 5th to 95th percentiles are used to derive the uncertainty bands. Except several outliers, the uncertainty bands encompass the observed gauge rainfall quite well. The parameters of the ensemble generator vary considerably for each season, indicating the seasonal ensemble generator reflects the impact of seasons on radar rainfall uncertainty. This study is an attempt to simultaneously consider four key features of radar rainfall uncertainty and future study will investigate their impacts on the outputs of hydrological models with radar rainfall as input or initial conditions.  相似文献