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Predicting the streamflow of rivers can have a significant economic impact, as this can help in agricultural water management and in providing protection from water shortages and possible flood damage. In this study, two statistical models have been used; Deseasonalized Autoregressive moving average model (DARMA) and Artificial Neural Network (ANN) to predict monthly streamflow which important for reservoir operation policy using different time scale, monthly and 1/3 monthly (ten-days) flow data for River Nile basin at five key stations. The streamflow series is deseasonalized at different time scale and then an appropriate nonseasonal stochastic DARMA (p, q) models are built by using the plots of Partial Auto Correlation Function (PACF) to determine the order (p) of DARMA model. Then the deseasonalized data for key stations are used as input to ANN models with lags equals to the order (p) of DARMA model. The performance of ANN and DARMA models are compared using statistical methods. The results show that the developed model (using 1/3 monthly (ten-days) and ANN) has the best performance to predict monthly streamflow at all key stations. The results also show that the relative error in the developed model result did not exceed 9% while in the traditional models reach to 68% in the flood months in the testing period. The result also indicates that ANN has considerable potential for river flow forecasting.  相似文献   
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The timing of deformation in the northern Zagros Folded Belt is poorly constrained because of the lack of an accurate absolute chronology of the syntectonic sedimentary sequences. The foreland basin infill in the northern part of the Fars arc is composed of supratidal sabkha deposits (Razak Fm), medium‐grained deltaic deposits (Agha Jari Fm) and coarse conglomerates of nearshore fan delta deposits at the base (Bakhtyari Fm, Bk1) and continental alluvial deposits at the top of the section (Bakhtyari Fm, Bk2). A magnetostratigraphic study was carried out in a composite section spanning about 1300 m on the northern flank of the Chahar–Makan syncline. Magnetostratigraphic correlation of the Razak Fm with chron C6n yields an age of 19.7 Ma at the base of the composite section. The transition to Agha Jari Fm is correlated with chron C5Cn, yielding an age of 16.6 Ma. The transition to the conglomerates of the Bakhtyari Fm (Bk1) correlates with the chron C5AD at approximately 14.8 Ma, which is considerably older than previously thought. The base of the Bakhtyari Fm growth strata, and thus the beginning of the deformation in northern Fars, is dated at 14–15 Ma. The topmost preserved Bakhtyari Fm (Bk1) is folded and unconformably overlain by Bakhtyari Fm (Bk2) conglomerates. This indicates that tectonic deformation in northern Zagros was already underway in the Middle Miocene.  相似文献   
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The status of medical facilities and personnel in the Kingdom of Saudi Arabia, at the end of the fourth five-year plan (1985–1990) was reviewed and analyzed regarding the standards of services and workload of health personnel for the different regions and urban/rural areas in the Kingdom. Innovative indices for the quantitative analysis of medical facilities were developed. The analysis of health facilities in Saudi Arabia shows that the Kingdom enjoys a high standard of medical facilities. However, there are maldistribution of clinical resources and personnel between regions and between urban/rural areas. Utilization of these indices for the reallocation of medical facilities and personnel to ensure even distribution of services for all inhabitants of the Kingdom was illustrated. In addition, indices give a guideline for the future planning and the rate of increase of these facilities that keeps the standard of medical services in the proper class desired with minimum resources wastage.  相似文献   
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Implementation of green management in sport complexes can ensure the continuous arrangement and assessment of activities from the environmental perspective and will end up in control and prevention of contaminants. Enghelab sport complex (ESC) in Iran is selected for this study due to its size and long-term activities. Due to the comprehensive plan of the aforesaid sports complex, numerous centers and departments were established in this site in order to materialize its envisioned sports, recreational and cultural objectives. The results of the questionnaires distributed amongst the members and the personnel of the complex revealed that approximately 50 % occupants were not acquainted with green management and only 30 % were faintly familiar with it. The personnel’s knowledge on green management was much better and about 64% of them were well acquainted with the related issues. Total amount of solid waste produced in the complex is about 547.5 tons/yr. in 2004; constituents are plastic (24.1 %), putrescible materials (45.9 %), glass (7.6 %), paper (19.3 %) and metal (3.1 %). According to the economic analysis conducted, the investment required for implementation of all the solid waste separation techniques amounts to us $ 11200. The result of present investigation is indicative of a medium level of optimization for energy and water consumption in ESC and there is a high potential to improve the efficiency of the system.  相似文献   
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A national satelite telecommunication model, which can be started by using Arabsat, was proposed to overcome the self-limiting geographical barrier and the maldistribution of clinical resources in the Kingdom. A national medical and phrmaceutical survey performed by the King Saud University showed an overwhelming acceptance of telemedicine (95.2%), telepharmaceutical (97%), telediagnosis (95.4%), urgent teleconsultation (for urgent operations) (74.5%) and for linking ambulance with hospitals (85.1%), continuing education via Arabsat (for physicians) (88.9%), medical technical staff (96.5%), pharmacists (75%) and public (91.5%), commercial marketing computer link for drug product and medical supply (92%) and centralizing Drug and Poison Information Centre (DPIC) (to provide information on drug interaction) (96%), drug substitution (92.5%) of novel and delivery systems (90.5%). Implementation of both telemedicine and telepharmaceutical services shall have an implication on improving the competency of medical staff, better health-care impact on citizen and better utilization of medical resources.  相似文献   
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In this paper, spatiotemporal variability of drought in Xilingol grassland during pasture growing season (from April to September) was investigated, using 52 years (1961–2012) of precipitation data recorded at 14 rain gauge stations in the study area. The Standardized Precipitation Index was used to compute the severity of drought. The Mann-Kendall test, the linear trend, and the sequential Mann-Kendall test were applied to standardized precipitation index (SPI) time series. The results indicate that drought has become increasingly serious on the region scale during pasture growing season, and the rate of SPI decreases ranged from ?0.112 to ?0.013 per decade. As for the MK test, most of the stations, the Z value range is from ?1.081 to ?0.005 and Kendall’s τ varies from ?0.104 to ?0.024. Meanwhile, drought is increased obviously from the northwest to the southeast region. Meanwhile, the occurrence probability of each severity class, times for reaching different drought class from any drought severity state, and residence times in each drought class have been obtained with Markov chain. Furthermore, the drought severities during pasture growing season in 2013–2016 are predicted depending on the weighted Markov chain. The results may provide a scientific basis for preventing and mitigating drought disaster.  相似文献   
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Journal of Seismology - In this study, seismic moment, moment magnitude, and the corner frequency of Iranian earthquakes were estimated using the Iran Strong Motion Network (ISMN) data. To estimate...  相似文献   
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