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Monitoring temporal variation of streamflow is necessary for many water resources management plans, yet, such practices are constrained by the absence or paucity of data in many rivers around the world. Using a permanent river in the north of Iran as a test site, a machine learning framework was proposed to model the streamflow data in the three periods of growing seasons based on tree-rings and vessel features of the Zelkova carpinifolia species. First, full-disc samples were taken from 30 trees near the river, and the samples went through preprocessing, cross-dating, standardization, and time series analysis. Two machine learning algorithms, namely random forest (RF) and extreme gradient boosting (XGB), were used to model the relationships between dendrochronology variables (tree-rings and vessel features in the three periods of growing seasons) and the corresponding streamflow rates. The performance of each model was evaluated using statistical coefficients (coefficient of determination (R-squared), Nash-Sutcliffe efficiency (NSE), and root-mean-square error (NRMSE)). Findings demonstrate that consideration should be given to the XGB model in streamflow modeling given its apparent enhanced performance (R-squared: 0.87; NSE: 0.81; and NRMSE: 0.43) over the RF model (R-squared: 0.82; NSE: 0.71; and NRMSE: 0.52). Further, the results showed that the models perform better in modeling the normal and low flows compared to extremely high flows. Finally, the tested models were used to reconstruct the temporal streamflow during the past decades (1970–1981).

In this work, We made fiber cement blocks by using the raw materials of Cement, Rice husk ash, Fine aggregate, Fibers of Chemical pulps (CP) and Thermomechanical pulps (TMP). The replacement amount were zero (control), 5, 10, 15, 20 and 25%. In total 36 cement blocks with dimensions of 15 * 15 * 15 cm were made. The properties of blocks which were measured include compressive strength, water absorption, density of before and after soaking. The data Statistically analysed by Spss software. Statistical analysis showed that the type of fibers had significant effect on both mechanical and physical properties at confidence level of 0.05. Based on the findings of this work, The CP fibers had better effects on the compressive strength of specimens than The TMP fibers approximately twofold. Increasing the replacement level of TMP fibers tends to reduce the compressive strength due to the low binding ability. The water absorption and density values of specimens contain fibers were lower than control. The fibers cause lighter weight, resistance to cracking and a degree of flexibility.

In this study, communication subsystem design of satellite constellation is performed based on inter-satellite-link idea. Three CubeSats are linked together as constellation form. To do this, orbit is intended in low earth and sun synchronous orbit in 600 Km altitude. Based on CubeSat design limitation and requirements, antenna is designed with deployable mechanism. S-band is considered for inter-satellite-link mission and X-band is selected for ground station data transfer. Link budget is calculated by considering losses for S & X-band. A high gain parabolic reflector antenna is designed and simulated as new idea. Finally, the simulation results show, satisfaction of requirements.

Precipitation forecasting plays a key role in natural resource management, agriculture management, and water requirement provision. Hence, dendroclimatology methods and artificial neural network (ANN) are used to estimate precipitation values in the past times. Moreover, a geographic information system (GIS) can be applied as a tool to demonstrate the spatial variation of precipitation. In this study, earlywood vessel features and tree-rings of Siberian elm species were used to simulate precipitation. The vessel features, the tree-ring extent, and the secondary data of climatologic station from the different sites were studied. At first, cross-dating and standardization of the tree-rings and vessels were performed. Then, time series analysis was done. In the next step, the relations between vessel chronologies and tree-rings with the precipitation were defined. The input parameters were selected tree-ring width and vessel features for the modeling, whereas precipitation of the growing season was selected as the output. The model or network was trained and verified by taking a case study of Fomanat plain (northern part of Iran). The results showed that the combinatory usage of vessel features and tree-rings extent in precipitation simulating can increase simulation capability. Further, different isohyets were generated using the simulated precipitation values, an interpolation technique in a GIS system. The results showed that the highest precipitation and the lowest precipitation have occurred in 1926 and 1986 during the last century.

The classification of roundwood is inextricably linked to the measurement of a particular single wood defect. The appearance, location, and number of defects are important in the quality evaluation...

Monitoring changes in groundwater storage is necessary for water resource management plans. The temporal records of spring discharge are restricted by the absence or paucity in many parts of the world. To address this shortcoming, various models and methods have been implemented to reconstruct past hydrologic data. In this study, temporal variations of spring discharge were reconstructed using tree-rings and earlywood vessel chronologies in an alluvial aquifer on the southern coast of the Caspian sea. The dendrochronological analysis was performed using both cross-sections and core samples of Zelkova carpinifolia (Pall.) K. Koch species, including tree-rings width and vessel features (vessels diameter, area, and perimeter) as proxy data. The distance between the sampling trees varied between 20 and 1000 m. An artificial neural network (ANN) was used to establish a relationship between the temporal dendrochronological records of Z. carpinifolia and corresponding discharge obtained from two alluvial springs in the vicinity of sampling trees. The ANN model was optimized and tested by comparing the recorded and predicted values in the training and testing stage of the modeling process. Results show the high performance of the ANN model in the training (R-squared = 0.98, MSE = 0.009) and test stage (R-squared = 0.81, MSE = 1.26). The results also indicated the higher correlation of springs discharge with vessel features (R = 0.76) compared to tree-rings (R = 0.59). Dendrohydrology works better for those springs with notable discharge changes during the growing seasons. Further, the combination of tree-ring width and vessel features as inputs in modeling will increase the model's performance. The tested model was applied to the dendrochronological records of past decades (1982 to 2001) to reconstruct the spring discharge data during the growing seasons for those years.

Dendrohydrogeology can be used to simulate historical groundwater depth, water table drawdown, groundwater recharge and piezometric lines. We simulated paleohydrogeologic conditions via tree-rings and vessel chronologies using an artificial neural network (ANN) in the alluvial aquifer of the Caspian southern coast of Iran during the past century. Tree-ring width, vessel features, secondary piezometric well data, and precipitation from different sites within the study area were evaluated. After cross-dating, standardization and time series analysis, the relationships between tree-rings and vessel chronologies with groundwater depth were defined and simulated. Additionally, paleohydrogeologic records during the past century were simulated. The results generally demonstrate that tree-ring width is a better index than vessel features. However, we obtained the most exact groundwater depth modeling results by using the combination of tree-rings and earlywood vessel diameter from periods of low precipitation and groundwater fluctuations and significant temperature fluctuations. We also found that dendrohydrogeology has more applicability in groundwater modeling in areas where groundwater depth fluctuates 10–20 m below ground surface (based on root depth and water access). Moreover, using the simulated groundwater depths, piezometric lines in 1927 and 2000 (the years with maximum natural recharge and maximum drawdown respectively) were extracted using an interpolation technique and Geographic Information System (GIS). Finally, we suggest applying dendrohydrogeology for paleohydrogeologic modeling in alluvial aquifers.

Climate change is currently one of the most important environmental issues. Dendrochronology is frequently used to identify the climatic changes most closely associated with changes in tree-ring extent. We applied dendroclimatology to determine the climate changes in the Roodbar region of Iran during the last four centuries. The climatic index of De Martonne (aridity index), annual precipitation, and annual mean temperature were simulated by using dendroclimatology (tree-rings) and an artificial neural network (ANN). Dendroclimatology studies were carried out with the use of the Cupressus sempervirens species. A multilayer perceptron network was adopted for the ANN. Tree-ring width was the input variable for the simulation, whereas annual precipitation, annual mean temperature, and the aridity index were the outputs. After the training process, the network was validated. The validated network and tree-rings were used to simulate changes in climatic factors during the last four centuries. The climatic factors simulated by using dendroclimatology can be used in drought studies and climate change evaluation. The results showed that in the last four centuries, the climate of the study area changed from semiarid to arid, and its annual precipitation decreased significantly. The significant changes in climate were found to occur in the mid-twentieth century.

Decayed wood samples were collected from naturally infected oak ( Quercus castaneifolia C.A.M.). Fruiting bodies of the basidiomycete white-rot fungus Pleurotus ostreatus were identified morphologically and confirmed with rDNA ITS sequencing. Cellulose and lignin compositions were determined and FT-IR spectroscopy was used to collect spectra from decayed and un-decayed wood samples. Histological aspects of decay were monitored by light microscopy. The results of the chemical analysis indicated that P . ostreatus decayed both cellulose and lignin in similar quantities. FT-IR analysis and microscopic images demonstrated that P . ostreatus exhibited simultaneous white-rot in naturally infected oak samples.

Summary Groundwater is the most important water resource in semi-arid and arid regions such as Iran. It is necessary to study groundwater level fluctuations to manage disasters (such as droughts) and water resources. Dendrochronology, which uses tree-rings to reconstruct past events such as hydrologic and climatologic events, can be used to evaluate groundwater level fluctuations. In this study, groundwater level fluctuations are simulated using dendrochronology (tree-rings) and an artificial neural network (ANN) for the period from 1912 to 2013. The present study was undertaken using the Quercus Castaneifolia species, which is present in an alluvial aquifer of the Caspian southern coasts, Iran. A multilayer percepetron (MLP) network was adopted for the ANN. Tree-ring diameter and precipitation were the input parameters for the study, and groundwater levels were the outputs. After the training process, the model was validated. The validated network and tree-rings were used to simulate groundwater level fluctuations during the past century. The results showed that an integration of dendrochronology and an ANN renders a high degree of accuracy and efficiency in the simulation of groundwater levels. The simulated groundwater levels by dendrochronology can be used for drought evaluation, drought period prediction and water resources management.

The impacts of white-rot fungi on altering wood chemistry have been studied mostly in vitro. However, in vivo approaches may enable better assessment of the nature of interactions between saprotrophic fungi and host tree in nature. Hence, decayed and sound wood samples were collected from a naturally infected tree (Carpinus betulus L.). Fruiting bodies of the white rot fungus Trametes versicolor grown on the same tree were identified using rDNA ITS sequencing. Chemical compositions (cellulose and lignin) of both sound and infected wood were studied. FT-IR spectroscopy was used to collect spectra of decayed and un-decayed wood samples. The results of chemical compositions indicated that T. versicolor reduced cellulose and lignin in similar quantities. Fungal activities in decayed wood causes serious decline in pH content. The amount of alcohol-benzene soluble extractives was severely decreased, while a remarkable increase was found in 1% sodium hydroxide soluble and hot water extractive contents in the decayed wood samples, respectively. FT-IR analyses demonstrated that T. versicolor causes simultaneous white rot in the hornbeam tree in vivo which is in line with in vitro experiments.

Rice stalk fiber and rice husk ash are agricultural by-products, which are available worldwide in large quantities. There is, however, no information about suitability of the rice stalk fiber and rice husk ash combination for the production of fiber-cement composites in the open literature. This paper presents a parametric experimental study, which investigates the potential use of rice stalk fiber (as reinforcement) and rice husk ash (as cement replacement) admixtures for producing a lightweight fiber-cement composite as a building material. Three levels of fibrous materials, namely 10, 25 and 40 wt% were mixed with 0, 10 and 20 wt% of rice husk ash. Effects of these variable parameters on the mechanical (modulus of rupture, modulus of elasticity and internal bond) and physical properties (water absorption and thickness swelling) of the samples were studied. The results showed the effect of high-level replacement of rice stalk fiber with rice husk ash does not exhibit a sudden brittle fracture even beyond the failure loads, indicating high energy absorption capacity of the composites. Based on the findings of this work, the water absorption and thickness swelling of the composites increased with the increasing rice stalk fiber content in the samples from 10 to 40 wt%. On the other hand, modulus of rupture and modulus of elasticity of the boards were enhanced with increase in the percentage of rice stalk fiber. Boards having 25 wt% rice stalk fiber exhibited the highest internal bond strength. However, addition of rice stalk fiber and rice husk ash reduced the internal bond strength. Moreover, boards made with rice stalk fiber had superior properties compared to boards made with a mixture of hardwood fibers.

Plant diversity plays key ecological roles in forest ecosystems, including influencing succession, resilience and nutrient cycling. This study was conducted to investigate the effect of livestock grazing and human uses on herbaceous species diversity. We surveyed 50 ha of protected area and 50 ha of unprotected area to evaluate herbaceous species diversity in oriental beech (Fagus orientalis Lipsky) forests in northern Iran. We calculated and compared three indices each of diversity and evenness, and species richness between the two areas. Herbaceous cover was higher in the unprotected area while leaf litter depth and tree canopy cover were higher in the protected area. The diversity indices, H (Shannon-Wiener index), N1 (McArthur index), N2 (Hill’s index), EQ (Modified Nee index), Evar (Smith-Wilson index), E5 (modified index of Hill) and R=S (species richness) and species richness R=S were greater in the protected area than in the unprotected area, suggesting that protection from grazing results in increased numbers of plants and species. The effect of land protection on plant diversity was more pronounced for evenness than for species richness and the positive correlation between diversity and evenness indices was higher than that between diversity and richness.

This work presents a parametric experimental study, which investigates the effects of partial replacement of Portland cement by wood fiber waste (WFW), rice husk ash (RHA), and limestone powder waste (LPW) for producing a lightweight concrete block as a building material. Some of the mechanical and physical properties of block materials having various levels of WFW, RHA, and LPW are studied. The compressive strength of the concrete blocks due to the filler effect decreased with increasing cement replacement. However, the results show the effect of 25 wt% replacement of RHA and LPW with Portland cement do not exhibit a sudden brittle fracture even beyond the failure loads, indicates high energy absorption capacity, reduce the unit weight dramatically. As expected, the increase of the RHA content induced the reduction of bulk density of the concrete blocks. Statistical analysis showed that the interactions of above-mentioned variable parameters were significant on both mechanical and physical properties at 5% confidence level. The optimum replacement level of WFW, LPW, and RHA was 25% by weight; this replacement percentage resulted in good physico-mechanical properties. Recycling of WSW, RHA, and LPW as promising raw material supplements appears to be viable solution not only to the environmental problem but also to the problem of the economic design of buildings.

Background: Despite the importance of post-exposure prophylaxis (PEP), studies conducted in Iran on PEP showed different findings and it is not well documented yet. Objectives: The current study aimed to evaluate the delayed time of PEP and associated factors in bitten people. Materials and Methods: This cross-sectional study was conducted on 397 subjects of animal bites in Khalilabad County, Northeast of Iran, from March 2012 to March 2013. The census method was employed to use the data on animal bites recorded in the rabies treatment center (RTC). Results: Overall, 93.4% of the subjects received PEP in less than 48 hours after exposure. Of the 397 subjects, 86.0% were male, 61.7% aged0- 30 years, and 64.7% lived in rural areas. The subjects were mainly bitten by domestic dogs (79.8%), most of the subjects (91.9%) were involved with superficial wounds, and the most common sites of the animal bite were legs (48.1%) and hands (40.6%). The bite incidents happened more frequently in spring (29.2%) followed by summer (26.7%). There was only significant difference in delayed PEP with respect to the type of biting animal (x2 = 30.8, P < 0.001). Conclusions: The rabies PEP is well monitored in the region and its delayed time depends on the type of biting animal especially domestic dogs. Considering the high proportion of stray and domestic dogs as a public health concern in the district, the educational programs and the rabies vaccinations of dogs is recommended in the community

Three-dimensional simulation of a multiphase flow is performed using the Eulerian-Eulerian finite volume method in order to evaluate the separation efficiency and velocity field of deoiling hydrocyclones. The solution is developed using a mass conservation-based algorithm (MCBA) with collocated grid arrangement. The mixture approach of the Reynolds stress model is also employed in order to capture features of turbulent multiphase swirling flow. The velocity field and separation efficiency of two different configurations of deoiling hydrocyclones are compared with available experimental data. The comparison shows that the separation efficiency can be predicted with high accuracy using computational fluid dynamics. The velocity fields are also in good agreement with available experimental velocity measurements. Special attention is drawn to swirl intensity in deoiling hydrocyclones and it is shown that the differences in velocity and volume fraction fields of different configurations are related to swirl distribution.

Dutch elm disease is the most common and destructive disease of the elm family. The pathogen of Ophiostoma novo-ulmi will systematically lead to the blockage of xylems and cavities, and will finally lead to the development of wilt symptoms. The present study aimed to compare the diameter size of vessels and the number of xylary rays in four species: Ulmus carpinifolia , Ulmus glabra , Zelkova carpinifolia and Celtis australis as important factors in host resistance to elm disease. To do this, some samples were randomly collected from 10 cm above the place of seedling’s inoculation. The test results showed that there was a significant difference at 1% probability level among the measured indicators in these four species, the maximum diameter of vessel and the maximum number of xylary rays belonged to U. carpinifolia . According to the results, Ulmus campestris was more sensitive towards Dutch elm disease as compared to the other three species, and C. australis had the greatest resistance to Dutch elm disease. Key words : Dutch elm disease, xylary rays, vessel, resistance.

This work assesses the effects of white rice husk ash (WRHA) as pozzolanic material, virgin kraft pulp (VKP), old corrugated container (OCC) and fibers derived from fiberboard (FFB) as reinforcing agents on some properties of blended cement composites. In the sample preparation, composites were manufactured using fiber-to-cement ratio of 25:75 by weight and 5% CaCl(2) as accelerator. Type II Portland cement was replaced by WRHA at 0%, 25% and 50% by weight of binder. A water-to-binder ratio of 0.55 was used for all blended cement paste mixes. For parametric study, compressive strength, water absorption and density of the composite samples were evaluated. Results showed that WRHA can be applied as a pozzolanic material to cement and also improved resistance to water absorption. However, increasing the replacement level of WRHA tends to reduce the compressive strength due to the low binding ability. The optimum replacement level of WRHA in mortar was 25% by weight of binder; this replacement percentage resulted in better compressive strengths and water absorption. OCC fiber is shown to be superior to VKF and FFB fibers in increasing the compressive strength, due to its superior strength properties. As expected, the increase of the WRHA content induced the reduction of bulk density of the cement composites. Statistical analysis showed that the interaction of above-mentioned variable parameters was significant on the mechanical and physical properties at 1% confidence level.