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211.
Zahra?Sharafi Naeimehossadat?AsmarianEmail author Saeed?Hoorang Amin?Mousavi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(10):2943-2950
Stomach cancer is the second most common cancer in Iranian men and the fourth most common cancer in Iranian women. The incidence rate of this cancer in Iranian men is almost 2.5 times that in women. The objective of this study was to investigate the trend of stomach cancer incidence rate in Iran in an 8-year time period (2003–2010) and also update the incidence estimates of stomach cancer. Data from a total number of 41,830 patients diagnosed with stomach cancer according to the International Classification of Diseases (C16) in 2003–2010 were analyzed. We used Bayesian spatial and Bayesian spatio-temporal models to study the relative risk and trend of stomach cancer incidence rate in Iran. Out of 41,830 stomach cancer registered patients, 72% were male. The average smoothed SIRs were 0.79, 0.82 and 0.78 for the general, female and male population, respectively. This shows a nearly stable incidence rate. The northwest of Iran had the highest incidence rate of stomach cancer. The trend of this rate was declining to the lowest rate in the southeast of the country. The estimated values of coefficient of the trend term for general, female and male population in this model were 0.0085, ? 0.018 and 0.0041, which indicate almost a stable fixed trend. The map of temporal trends also showed that although the incidence rate of this cancer is to some extent stable, in general, in the central and in the east of the country the incidence relative risk has increased over time. The prevalence of Helicobacter pylori infection, Lower socioeconomic status and Iodine deficiency were speculated to be relevant factors for the high incidence rates of stomach cancer in the northwest of Iran. Preventive measures in the north and northwest of Iran could have an effect on controlling this cancer in these areas. 相似文献
212.
Fatemeh?KarandishEmail author Seyed?Saeed?Mousavi Hossein?Tabari 《Stochastic Environmental Research and Risk Assessment (SERRA)》2017,31(8):2121-2146
Global greenhouse gases increase could be a threat to sustainable agriculture since it might affect both green water and air temperature. Using the outputs of 15 general circulation models (GCMs) under three SRES scenarios of A1B, A2 and B1, the projected annual and seasonal precipitation (P) and cardinal temperatures (T) were analyzed for five climatic zones in Iran. In addition, the probable effects of climate change on cereal production were studied using AquaCrop model. Data obtained from the GCMs were downscaled using LARS-WG for 52 synoptic stations up to 2100. An uncertainty analysis was done for the projected P and T associated to GCMs and SRES scenarios. Based on station observations, LARS-WG was capable enough for simulating both P and T for all the climatic zones. The majority of GCMs as well as the median of the ensemble for each scenario project positive P and T changes. In all the climatic zones, wet seasons have a higher P increase than dry seasons, with the highest increase (27.9–83.3%) corresponding to hyper-arid and arid regions. A few GCMs project a P reduction mainly in Mediterranean and hyper-humid climatic regions. The highest increase (11.2–44.5%) in minimum T occurred in Mediterranean climatic regions followed by semi-arid regions in which a concurrent increase in maximum T (2.9–14.6%) occurred. The largest uncertainty in P and cardinal T projection occurred in rainy seasons as well as in hyper-humid regions. The AquaCrop simulation results revealed that the increased cardinal T under global warming will cause 0–28.5% increase in cereal water requirement as well as 0–15% reduction in crop yield leading to 0–30% reduction in water use efficiency in 95% of the country. 相似文献
213.
Chatrsimab Zahra Alesheikh Ali Asghar Voosoghi Behzad Behzadi Saeed Modiri Mehdi 《Doklady Earth Sciences》2020,494(1):718-725
Doklady Earth Sciences - Land subsidence, as a dangerous environmental issue, causes serious damages to farms and urban infrastructure. In this regards, this research was conducted with aimed to... 相似文献
214.
Mohammad Saeed SEIF Ebrahim JAHANBAKHSH Roozbeh PANAHI Mohammad Hossein KARIMI 《中国海洋工程》2009,23(3):517-528
High speed planing hulls have complex hydrodynamic behaviors. The trim angle and drafts are very sensitive to speed and location of the center of gravity. Therefore, motion simulation for such vessels needs a strong coupling between rigid body motions and hydrodynamic analysis. In addition, free surface should be predicted with good accuracy for each time step. In this paper, velocity and pressure fields are coupled by use of the fractional step method. On the basis of integration of the two-phase viscous f... 相似文献
215.
A numerical simulation algorithm based on the finite volume discretisation is presented for analyzing ship motions. The algorithm employs a fractional step method to deal with the coupling between the pressure and velocity fields. The free surface capturing is fulfilled by using a volume of fluid method in which the interface between the liquid (water) and gas (air) phases are computed by solving a scalar transport equation for the volume fraction of the liquid phase. The computed velocity field is employed to evaluate the acting forces and moments on the vessel. Using the strategy of boundary-fitted body-attached mesh and calculating all six degrees-of-freedom of motion in each time step, time history of ship motions including displacements, velocities and accelerations are evaluated.To verify the proposed algorithm, a series of verification tests are conducted. First, a two-dimensional asymmetrical wedge slamming is simulated as a simple type of a common case for high-speed vessels. Then, the steady-state forward motion of a high-speed planing catamaran is investigated. Results of both test cases show good agreement with experimental data. It is concluded that the proposed algorithm can be a promising strategy for both performance prediction and design of high-speed vessels. 相似文献