APPLICATION OF GREY MODEL TOWARD RUNOFF FORECASTING1

ABSTRACT: A reliable forecasting model is essential in real‐time flood forecasting for reducing natural damage. Efforts to develop a real‐time forecasting model over the past two decades have been numerous. This work applies the Grey model to forecast rainfall and runoff owing to the model's relative ability to predict the future using a small amount of historical data. Such a model significantly differs from the stochastic and deterministic models developed previously. Ten historical storm events from two catchment areas in northern Taiwan are selected to calibrate and verify the model. Results in this study demonstrate that the proposed models can reasonably forecast runoff one to four hours ahead, if the Grey error prediction method is further used to update the output of the model.     

Perfluorinated compounds in a coastal industrial area of Tianjin,China

Perfluorinated compounds (PFC) in water, sediment, soil, and biota from the coastal industrial area of Tianjin, China, were measured to provide baseline information and to determine possible sources and potential risk to wildlife. Perfluorooctanesulfonate (PFOS) was the predominant PFC with maximum concentrations of 10 ng/L in water, and 4.3, 9.4, and 240 ng/g dw in sediment, soil, and fish, respectively. Perfluorooctanoate (PFOA) concentration in water ranged from 3.0 to 12 ng/L. Perfluoroundecanoate (PFUnA) and Perfluorododecanoate (PFDoA) were detected in solid matrices, respectively, at concentrations of 相似文献   

Receptor-mediated in vitro bioassay for characterization of Ah-R-active compounds and activities in sediment from Korea

Sediment extracts of stream sediments, collected from inland areas of Lake Shihwa (LSI) and Masan Bay (MBI), were screened for their abilities to induce aryl hydrocarbon receptor (Ah-R) mediated gene expression in vitro. Cell viability assay was also performed to examine cytotoxic effects on the Ah-R-mediated activities of sediment samples. Over 80% (30 out of 36) of sediment raw extracts (REs) induced significant Ah-R-mediated activities in the H4IIE-luc cell bioassays. Ah-R-mediated activities of sediment REs from LSI locations (mean=58%-TCDD-max; n=21) were greater than those of sediment REs from MBI locations (mean=35%-TCDD-max; n=15), in general. Seven (mean+/-SD=100+/-14%-TCDD-max) of 21 sediment REs from LSI showed Ah-R-mediated activities comparable to that (set to, 100%-TCDD-max) elicited by 1240 pM TCDD. Whereas, in MBI, only two REs from M1 (93%-TCDD-max) and M9 (82%-TCDD-max) showed significantly great responses that comparable to maximum response of TCDD standard curve. Sample potencies relative to the TCDD standard (TCDD-EQs) were estimated based on full dose-response characteristics of REs and TCDD-EQs were found to be 14-868 pg TCDD/g, dw and 17-275 pg TCDD/g, dw, in LSI and MBI, respectively. A range of TCDD-EQ20-80 of samples, based on multiple estimates of relative potency (REP20-80), did not vary greatly (2-4-fold) in the H4IIE-luc bioassays, which indicated relatively low degree of uncertainties in point estimates of REP for sediment REs examined. Acid-treatment of REs samples improved quantitative biological responses of samples followed by decreases in cytotoxicity identified by MTT cell viability assays.     

Polychlorinated biphenyls,polycyclic aromatic hydrocarbons and alkylphenols in sediments from the Odra River and its tributaries,Poland

Concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), nonylphenol (NP) and octylphenol (OP) were measured in sediments collected during June–August 1998 along the Odra River and its tributaries (Warta, Obrzyca, Barycz, Kaczawa and Bóbr Rivers) in Poland. In addition, raw and treated sewage sludge collected from Gdańsk, Poland, were analyzed for the target compounds. Concentrations of PCBs in sediments varied widely, ranging from 2.7 to 412?ng/g, on a dry weight basis (dry wt). PAHs were the predominant compounds in sediments with concentrations ranging from 150 to 19?000?ng/g, dry wt. The distribution of concentrations of PAHs was more homogenous than that of PCBs. NP concentrations in sediments ranged from <1 to 762?ng/g, while that of OP from <1 to 9.8?ng/g, dry wt. Measured concentrations of target analytes in sediments of the Odra River and its tributaries were comparable to or greater than those reported for riverine sediments in other eastern European countries. Concentrations of total PCBs, PAHs and NP in raw and treated sewage sludge collected from a sewage treatment plant in Gdańsk, Poland, were in the ranges of 203–284, 11?720–13?880 and 6760–99?600?ng/g, dry wt, respectively. Primary treatment of sewage did not appear to reduce PCB or PAH concentrations, although NP and OP concentrations were much less in treated sludge than in raw sludge. This is one of a few studies that document concentrations of PCBs, PAHs and NP in sediments of the Odra River and its tributaries in Poland.     

Identification of sources contributing to Mid-Atlantic regional aerosol

Source types or source regions contributing to the concentration of atmospheric fine particles measured at Brigantine National Wildlife Refuge, NJ, were identified using a factor analysis model called Positive Matrix Factorization (PMF). Cluster analysis of backward air trajectories on days of high- and low-factor concentrations was used to link factors to potential source regions. Brigantine is a Class I visibility area with few local sources in the center of the eastern urban corridor and is therefore a good location to study Mid-Atlantic regional aerosol. Sulfate (expressed as ammonium sulfate) was the most abundant species, accounting for 49% of annual average fine mass. Organic compounds (22%; expressed as 1.4 x organic carbon) and ammonium nitrate (10%) were the next abundant species. Some evidence herein suggests that secondary organic aerosol formation is an important contributor to summertime regional aerosol. Nine factors were identified that contributed to PM2.5 mass concentrations: coal combustion factors (66%, summer and winter), sea salt factors (9%, fresh and aged), motor vehicle/mixed combustion (8%), diesel/Zn-Pb (6%), incinerator/industrial (5%), oil combustion (4%), and soil (2%). The aged sea salt concentrations were highest in springtime, when the land breeze-sea breeze cycle is strongest. Comparison of backward air trajectories of high- and low-concentration days suggests that Brigantine is surrounded by sources of oil combustion, motor vehicle/mixed combustion, and waste incinerator/industrial emissions that together account for 17% of PM2.5 mass. The diesel/Zn-Pb factor was associated with sources north and west of Brigantine. Coal combustion factors were associated with coal-fired power plants west and southwest of the site. Particulate carbon was associated not only with oil combustion, motor vehicle/mixed combustion, waste incinerator/industrial, and diesel/Pb-Zn, but also with the coal combustion factors, perhaps through common transport.     

46,XY,dup(10q) in direct CVS preparation and mosaic 48,XXXY,dup(10q) in CVS long-term culture and fetal tissue

Chorionic villus sampling (CVS) was performed on a 40-year-old woman at 9 1/2 menstrual weeks because of advanced maternal age. The direct preparation showed 46,XY,dup(10)(q11.2q23.2). CVS long-term culture and fetal tissue revealed a rare additional abnormality: 48,XXXY,dup(10)(q11.2q23.2). This abnormality represented the major cell line (>85 per cent in 691 cells) in an (XY)/XXY/XXXY/(XXXXY) mosaic (all cell lines presumably bearing the dup(10q); the presence of XY and XXXXY cell lines is uncertain). To our knowledge, this is the first report of trisomy 10q11-q23 and of prenatally detected 48,XXXY in chorionic villi. The mosaic could have resulted from early post-zygotic non-disjunctions in a 46,XY,dup(10q) or 47,XXY,dup(10q) zygote. The results from DNA studies of four polymorphisms, mapped to Xp and Xq, support this theory. The literature on prenatally detected cases with sex chromosome tetrasomy and pentasomy and those with additional autosomal abnormalities is reviewed. The reported case underlines the problem of false-negative findings when only direct CVS preparations are karyotyped.     

OPTIMAL MANAGEMENT OF A REGIONAL AQUIFER IN EASTERN SAUDI ARABIA1

ABSTRACT: This paper describes the formulation and application of a ground-water hydraulic management model to determine the optimal development and operating policies of a regional aquifer in the Eastern Province of Saudi Arabia. The hydraulic response of the aquifer system is represented by a simulation model that is linked to an optimization management model using response functions. Yearly optimal ground-water extraction rates over a planning horizon of 15 years are determined for four scenarios, each reflecting alternative ground-water development policies. The results are presented in the form of tradeoff curves, relating drawdowns to optimal pumpage, which may enhance the decisionmaker's ability to select the best development policy from a set of alternatives. The results illustrate how various optimal management schemes can be devised to increase the total withdrawal from the aquifer while preventing excessive de-watering.     

Removal of heavy metals using waste eggshell

The removal capacity of toxic heavy metals by the reused eggshell was studied.As a pretreatment process for the preparation of reused material from waste eggshell,calcination was performed in the furnace at 800℃for 2 h after crushing the dried waste eggshell.Calcination behavior,qualitative and quantitative elemental information,mineral type and surface characteristics before and after calcination of eggshell were examined by thermal gravimetric analysis(TGA),X-ray fluorescence (XRF),X-ray diffraction(XRD) and scanning electron microscopy(SEM),respectively.After calcination,the major inorganic composition was identified as Ca(lime, 99.63%)and K,P and Sr were identified as minor components.When calcined eggshell was applied in the treatment of synthetic wastewater containing heavy metals,a complete removal of Cd as well as above 99% removal of Cr was observed after 10 min. Although the natural eggshell had some removal capacity of Cd and Cr,a complete removal was not accomplished even after 60 min due to quite slower removal rate.However,in contrast to Cd and Cr,an efficient removal of Pb was observed with the natural eggshell rather than the calcined eggshell.From the application of the calcined eggshell in the treatment of real electroplating wastewater, the calcined eggshell showed a promising removal capacity of heavy metal ions as well as had a good neutralization capacity in the treatment of strong acidic wastewater.     

Application of the “Climafor” baseline to determine leakage: the case of Scolel Té

The acceptance of forestry-based project activities to mitigate greenhouse gases emissions has been subjected to a number of methodological questions to be answered, of which the most challenging are baseline establishment and identification of and measuring leakage. Here we pose hypotheses for and quantify leakage of the Scolel Té project in Chiapas, Mexico. In this project small-scale farmers are implementing forestry, agroforestry, and forest conservation activities, with carbon sequestration as one of the goals. The main leakage monitoring domain is defined as the area owned by the participating farmers or communities outside the area where the specific project activities take place. The null-hypothesis (no leakage) is that non-project land owned by the farmer or community will experience the same carbon stock changes as predicted by the regional baseline, specifically developed for the project. First we assessed the most likely causes and sources of leakage that may occur in the project. From this analysis, one type of leakage seems to be important, i.e., activity shifting. Second we estimated the leakage of a sample of participating farmers and communities. Actual land use was then compared with expected land use derived from the baseline. The Plan Vivo of each participant, complemented with readily available tools to identify the main sources and drivers of leakage are used to develop simple leakage assessment procedures, as demonstrated in this paper. Negative leakage was estimated to be negligible in this study. Incorporating these procedures already in the project planning stage will reduce the uncertainties related to the actual carbon mitigation potential of any forestry project.

Assessment of potential benefits of traffic and urban mobility reductions during COVID-19 lockdowns: dose-response calculations for material corrosions on built cultural heritage

Environmental Science and Pollution Research - Air pollution, particularly in urban areas, puts human health in danger and has adverse impacts on the built environment. It can accelerate the...