توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱NON–PRISMATIC EFFECT ON THE SCATTERING OF SH–WAVES IN 3–D CANYONS
نویسنده(ها): ، ، ،
اطلاعات انتشار: پنجمین کنفرانس بین المللی زلزله شناسی و مهندسی زلزله، سال
تعداد صفحات: ۱۱
The scattering of seismic waves by topographic irregularities can amplify ground motion and intensify damages such as the activation of landslides and rock failures during earthquakes. The scattering of waves by topographies in canyons causes spatial variation of the earthquake ground motion which should be considered in the analysis and design of large structures located at these sites. It is common for topographic effects of canyons to be analyzed using 2–D models that assume the canyons to be prismatic. In order to investigate non–prismatic effect of 3–D canyon on the scattering of SH–waves two cases are analyzed. First case is the canyon with semi–circular cross section widening toward both ends and the second one is the canyon narrowing toward ends. The analysis uses an extended 3–D multi–domain boundary element method. A comparison of results for prismatic and non–prismatic canyons shows that the non–prismatic canyon could strongly affect the amplification and the variation of ground motion along the canyon. The significance of these effects depends on the pattern of cross–section variation along the canyon length, as well as the incident wave direction. It is shown that non–prismatic effect for the canyon widening toward ends amplifies the topographic effect in respect to the prismatic solution. As arch dam sites resemble this type of canyons, the latter might have a high impact on he seismic loads for the dam. However the canyon narrowing toward ends de–amplify the topographic amplification. Thus it is concluded that for non–prismatic canyons a 3–D solution is essential in order to get an accurate perspective of the phenomena of topography.<\div>

۲PCBs removal from transformer oil by solvent extraction
نویسنده(ها): ، ،
اطلاعات انتشار: بیستمین کنفرانس بین المللی برق، سال
تعداد صفحات: ۶
Extraction and destruction of Polychlorinated Biphenyls (PCBs) as a major persistent organic pollutants (POPs) compound, has been attracted many environmental research activities. Mostly, this compound had been produced for use in electrical equipment, especially as transformer oil. PCBs problem has caused to quarantine an enormous volume of such expensive oil. This study has been directed towards the development of a cost – effective technology for removing PCBs from contaminated transformer oils to methanol, so that oil remains usable. PCBs extraction by
methanol has two benefits: 1– easy destruction by Pd\Fe catalyst in aqueous solutions. 2– oil’s usefulness without necessary to apply additional processes. In this research, PCBs extraction data and its equilibrium behavior in oil – methanol phases have been presented. Extraction effects on oil characteristics and results have been inspected. L2000–Dexil analyzer as a choice for PCBs analysis among standard approaches, has restrictions in methanol. To solving this problem, a new method has been introduced to analyze PCBs in methanol solutions.<\div>

۳Crosslink Density of Epoxy Cured Acrylic Resins at Different Temperatures
نویسنده(ها): ، ، ،
اطلاعات انتشار: دهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۱۰
Crosslink density (XLD) is one of the important structural parameters characterizing a crosslinked polymer. Physical and mechanical properties of crosslinked polymer are significantly influenced by variation in the magnitude of XLD. In the present work, a carboxyl functional acrylic resin was crosslinked with different epoxy resins. Their films were immersed in methyl ethyl ketone and the increase in dimensions of the swollen films under equilibrium swelling conditions was used to calculate crosslink density by using the Flory–Rehner equation. Results demonstrated
that the crosslink density increased by increasing in crosslinker content and cure temperature but it decreased by increasing the molecular weight of crosslinker. It was also found that the curing reactions were going to completion at 170oC and 40 min when the carboxyl\epoxy ratio was 1:1. The mentioned conditions are important from a commercial point of view.<\div>

۴A numerical study of the aspiration efficiency of a thin–walled sampler in subisokinetic sampling
نویسنده(ها): ، ،
اطلاعات انتشار: دهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۸
In this paper the efficiency of a subisokinetic thin–walled sampling tube facing the moving air is investigated with three–dimensional numerical model. Continuity and Navier–Stokes equations are solved to find the flow field around and inside of the sampler probe. Momentum equations are discretized using the control volume approach.
Governing equations for particles’ motion are solved in a lagrangian reference frame. Having the particles’ paths, aspiration efficiency of the sampler is determined. Three particle sizes, characterized by aerodynamic diameter of 13, 34 and 89.5 µm, were considered. Then, in order to validate the numerical results, present work is compared with the previous experimental and numerical works. The previous numerical works for prediction of the sampling efficiency were not accurate at high values of velocity ratios. The results of this work show that the viscous effects play an important role on modeling of the sampler performance and the aspiration efficiency is affected by the gravitational effects.<\div>

۵Implementation of fast motion estimation algorithms and comparison with full search method in H.264
نویسنده(ها): ، ،
اطلاعات انتشار: پانزدهیمن کنفرانس مهندسی برق ایران، سال
تعداد صفحات: ۶
In this paper, Three motion estimation algorithms for H.264 standard have been implemented and performance and some features of these three have been tested. These algorithms are full search and two fast search method. Finally some parameters such as bit rate, speed up and PSNR for different value of QP have been compared. Implementation has been performed in Matlab software.<\div>

۶NUMERICAL SIMULATION OF PARTICLE–SURFACE INTERA CTION IN A TURBULENT CHANNEL FLOW
نویسنده(ها): ، ،
اطلاعات انتشار: سیزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۱۰
This study presents a computational model for Lagrangian simulation of particle transport, dispersion, deposition and rebounding in a turbulent channel flow. An empirical mean velocity profile for the fluid velocity and experimental data for turbulent intensities are used for the current case. The instantaneous fluctuating velocities are simulated as continuous Gaussian random fields. The particle equation of motion takes into account the Stokes drag, the Saffman lift, the Brownian, and the gravitational forces. The Brownian diffusion is simulated as a white noise process. Starting with an initially uniform concentration near the wall an ensemble of particle trajectories is generated and statistically analyzed. Several simulations for deposition of aerosol particles of various sizes are performed and the corresponding deposition velocities are evaluated. The effect of particle rebound from surface on particle deposition velocity is also taken into consideration. The computational model predictions for particle deposition velocity are compared with the existing experimental data and earlier simulation results and favorable agreements are observed.<\div>

۷Slab Method and Experimental Analysis of Indentation Forging of Tubes
نویسنده(ها): ، ،
اطلاعات انتشار: سیزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۷
In this paper, Generalized slab method (GSMA) is used to study the indentation forging of thick walled tubes. Axisymmetric slab model is developed to study the effects of various parameters such as lubrication and thickness of tube on the loads required for feeding the tool inside the tube. Various mandrel geometries are considered. Experiments are carried out to verify the model and reasonable agreement between experimental and analytical results is observed.<\div>

۸VIBRATION OF FILAMENT WOUND LAMINATED CIRCULAR CYLINDRICAL SHELLS WITH ORTHOGONAL STIFFENERS
نویسنده(ها): ،
اطلاعات انتشار: پانزدهمین کنفرانس سالانه مهندسی مکانیک، سال
تعداد صفحات: ۸
In this paper, the vibration analysis of simply supported cross–ply laminated cylindrical shells with discrete axial and circumferential stiffeners is presented. The classical shell theory based on Love–Kirchhoff hypothesis with the first order shear deformation is compared in order to have better estimating on vibrating response of laminated shells. The energy procedure is applied to obtain the dynamic characteristics of structures. The effects of geometry of shell, stiffeners and laminate stacking sequences on natural frequencies and vibration mode shapes are examined.<\div>

۹Multi–Features and Multi–Stages RBF Neural Network Classifier with Fuzzy Integral in Face Recognition
نویسنده(ها): ،
اطلاعات انتشار: چهارمین کنفرانس ماشین بینایی و پردازش تصویر، سال
تعداد صفحات: ۷
This paper presents a high accuracy human face recognition system using multi–feature extractors and multi–stages classifiers (MFMC), which are fused together through fuzzy integral. The classifiers used in this paper are Radial Basis Function (RBF) neural network while feature vectors are generated by applying PZM, PCA and DCT to the face images separately. Each of the feature vectors are sent to an RBF neural network classifiers and the output of these classifiers are fused to obtain better recognition rate. Experimental results on the ORL and Yale
database yield excellent recognition rate.<\div>

۱۰Evaluation of fatty acids effects on apatite and iron oxides wettability and their prediction by fuzzy logic
نویسنده(ها): ، ،
اطلاعات انتشار: پنجمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۹
Determination of minerals wettability is essential in understanding the performance of flotation process. Contact angle measurement is an indicative of a mineral wettability. In the present study, the effects of two fatty acids based collectors, which are the most common collectors used in floating apatite from iron oxides, on wettability of apatite and iron oxide (magnetite) minerals in various experimental conditions is investigated. Nonlinear relationship among these parameters in contact angle change i.e. type and concentration of collector, pH, and the cations concentration are simulated as a MISO (multi input–single output) fuzzy model by means of the power of fuzzy logic technology in implementing and modeling the real world’s data. A good correlation had been perceived between experimental and model data.<\div>

۱۱A Comprehensive Comparison between Three Practical Topologies of the Load–Balancing Transformers
نویسنده(ها): ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی الکترونیک قدرت و سیستم های درایو، سال
تعداد صفحات: ۴
Load–balancing transformer is a three–phase transformer which has a pair of additional coupling winding in the secondary–side of each phase. One of the coupling windings from each phase is in series with that of the other phase and the set of these two windings is reversely paralleled with the secondary winding of the third phase. Under unbalanced condition, the unbalanced current flows through the coupling and secondary windings that each winding is fed from primary by using a separate phase. In this way, part of excess current of one phase is transferred to the other phases. In this paper based on the original load–balancing transformer, two new load–balancing transformers are presented. Two proposed and original load–balancing transformers are simulated with MATLAB and the results are discussed.<\div>

۱۲Density Functional Study of the I–V Characteristicsof the Ethane–dithiol (C2H4S2) Nano–Molecular Wire
نویسنده(ها): ،
اطلاعات انتشار: ششمین همایش سراسری علوم پایه، سال
تعداد صفحات: ۱۴
We report a first–principles study of electrical transport in a singlemolecular conductor consisting of a ethane–dithiol (C2H4S2) sandwichedbetween two Au (100) electrodes. We show that the current was increased byincreasing of the external voltage biases. The projected density of states(PDOS) and transmission coefficients (T(E)) under various external voltagebiases are analyzed, and it suggests that the variation of the coupling betweenthe molecule and the electrodes with external bias leads to the increase of thecurrent. Therefore, we propose that the most origin of electron transportmechanism in molecular devices is caused by the characteristics of both themolecule and the electrodes as well as their cooperation.Furthermore, the transport properties of the buthane–dithiol (C4H6S2)molecular wire is investigated, too. The results show that the buthane–dithiolmolecular wire has a lower conductivity than the ethane–dithiol ones at variousexternal biases thus, it is a better insulator device for the molecular electronicstechnology<\div>

۱۳Fatal and Non–Fatal Work Related Injuries Among Workers of Iranian Aluminum and Copper Industries Between 2003 and 2011
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۶
One–third of globally, injuries to the adults in the world were related to workers and work situations. The aim of the present study was determining of work–related injuries rate among workers at two main metal industries (aluminum and Cooper industries) and independent predictors of fatal work–related injuries among them. Present cross–sectional study was assessed fatal and not fatal work–related injuries among 11172 workers into two groups of Iranian metal industries between April 2003 and September 2011. Information was obtained from the electronic registry of work–related injuries to the health & environment office of Iranian Mines and mining Industries Development and Renovation Organization of the Iranian industrial ministry. Binary logistic regression was used for determining predictors of fatal work–related injuries. During the study period, 55 workers of metal companies had been dyed and mortality rate among study workers was 1.7% and 3282 work–related injuries were reported. Mortality rate in study workers had significant association with injury location (P≤0.00), worker''s age (P≤0.00) and not significant association with worker''s shift (P≥0.44), educational level (P≥0.46), injury type (P≥0.65) and work experience (P≤0.07). In linear regression model analysis only age of workers was independent mortality predictors among study workers. Based on our findings work–related injuries in mentioned industries in this study setting are high, and a comprehensive injury prevention program seems to be essential.

۱۴Musculoskeletal Disorders among Iranian Coal Miners at 2014
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۶
Some factors such as stooping posture and frequent kneeling in miners can increase prevalence of their musculoskeletal disorders Present study was performed for assessment of MSDs prevalence among Iranian coal miners and finds its relationships with some their characters including age, work experience and body mass index. Participants in the persent cross sectional study, were 505 coal miners which selected among Iranian coal miners by simple random method. Data of musculoskeletal disorders (MSDs) gathered by Standardized Nordic self–reporting questionnaire. Demographic and work related data were collected into the check list. Findings of persent study showed that 56.1% and 66.5% of study miners claimed one of the MSDs complaints during last week and in the last year respectively. Lumbar, Knee(s) and Back had most common MSDs prevalence at last week and year. MSDs prevalence had significant association with age (P≤0.02) and non–significant association with BMI (P≥0.8) of workers. MSDs in Iranian coal miners were happened in high rate. Ergonomic interventions strategies in the workplaces must be focussed for elimination of environmental hazards such as apposition at the time of work, manual handling of heavy loads.

۱۵Occupational Stress in Development Musculoskeletal Disorders Among Embassy Personnel of Foreign Countries in Iran at 2015
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۶
Concept of occupational stress and its relations with musculoskeletal disorders has been investigated for years. The present study was performed for determining the role of occupational stress in the development of musculoskeletal disorders (MSDs) among embassy personnel of foreign countries in Iran. Study population in the present cross sectional study was 200 embassy personnel of foreign countries in Tehran capital of the Islamic Republic of Iran. Study questionnaires (Nordic Questionnaire; The occupational stress scale) were distributed into participants and finally 161 questionnaires come back to the researchers (response rate: 80.5%). One week and one year period prevalence of musculoskeletal complaints of included embassy personnel were 59.6% and 75.2% respectively. Mean of occupational stress in embassy personnel with musculoskeletal disorders in recent week and year were significantly higher than embassy personnel without musculoskeletal disorders. Smoking and occupational stress score were independent predictor of musculoskeletal disorders. Occupational stress had an impact on development and persistence of WRMSDs among embassy personnel and next studies in this new field will suggest for more detecting actual causes of WRMSDs in these persons and other office workers.

۱۶Neck and Back Pain Prevalence in Workers of Iranian Steel industries at 2015
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۵
Work related musculoskeletal disorders (WMSDs) are considered as the main cause of occupational complications and disability in developing countries. In Iranian steel companies, workers commonly are directly involved in the production process and physical activities such as manual material handling and awkward postures. Present study was performed for assessment of neck and back pain prevalence among workers of four Iranian steel industries. Study participants in our cross sectional study, were randomly selected from workers of four Iranian steel industries. Data of neck and back pain were gathered by Nordic questionnaire. Logistic regression was used for controlling confounding variables and determining independent predictors of neck and back pain among study workers. Among study workers, prevalence of neck and back pain in a recent year were 18.40% and 13.90% respectively. Age (p≤0.02) and job experience (p≤0.00) had significant association with neck pain. Age, sex, BMI, and job duration were not known as an independent predictor of neck or back pain. Neck and back pain prevalence in steel industries were happened whit higher rate compared to most of other countries. Next studies will suggest for determining work related risk factors of WMSDs in workers and designing preventive strategies.

۱۷Role of Rice Farming in Development Risk of Musculoskeletal Disorders Among Rice Farmers: a Prospective Study in 2013
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۶
Farming as job, had some activities or work task such as strenuous physical tasks and high levels of manual labor in farming job, which can increase risk of MSDs among farmers. Present study with prospective design designed for assessment role of rice farming in developmental risk of MSDs among Iranian rice farmers. Present prospective study was performed on 75 rice farmers of Babol city in Iran and 75 participants without history of rice farming, during March 2013 until September 2013. At the beginning of the study, participants did not have any musculoskeletal complaints in each of their body parts. Study exposure in the present study was working in the rice farming workplace for one rice farming period which at least lasted for four months. Frequency of MSDs had been assessed by Nordic questionnaire at three follow–up points. We followed 75 rice farmers of Babol city as expose and compare them with 75 participants without history of rice farming. Within the six months follow–up, MSDs complaints in 38 (50.66%), 61 (81.33%) and 47 (63.51%) rice farmers had been reported respectively in upper limbs, spinal and lower limbs regions. In the present study, rice farming was reported as a risk factor for MSDs in the spinal region and lower limbs.

۱۸Quality of Life and Mental Health Status Among Iranian Blue Workers With Self–Reported Chronic Low Back at 2015
اطلاعات انتشار: Iranian Journal of health، سوم،شماره۱، Winter ۲۰۱۶، سال
تعداد صفحات: ۴
Musculoskeletal disorders such as low back pain can cause a wide spectrum of chronic complications such as quality of life and general health impairment. Mental health is a wide spectrum of concepts that which those such as anxiety, depression or even quality of life had challengeable impacts on work related characters such as worker productivity, absensism. Present study was performed for evaluation of low back pain prevalence and its association with general health and quality of life status among blue workers of Fars ABFA Company. In the present study we focused on low back pain among 451 blue workers and assessed their mental health status and quality of life status with general health questionnaire (GHQ–28) and short form questionnaire (SF–36) respectively. In comparison one–year prevalence of low back pain was 44.2%. Mean of SF36 (63.90 ± 17.39 vs. 79.42 ± 15.01; P≤0.001) and General health subdomains (58.29 ± 19.63vs. 69.84 ± 18.63; P≤0.001) for workers with low back pain were significantly lower than other workers. Findings of our study showed that low back pain had impact on mental health status and quality of life among workers and these changes must consider in the designing preventive program more than control of pain.

۱۹An ethno–medicinal study of medicinal plants used for the treatment of diabetes
اطلاعات انتشار: Journal of nephropathology، پنجم،شماره۱، Jan ۲۰۱۶، سال
تعداد صفحات: ۷
Background: Diabetes is the greatest public health problem and is considered as the silent epidemic of the 21st century. In Iran, there are approximately 1.5 million diabetic patients. Before the discovery of insulin, medicinal plants were widely used for the treatment of diabetes in Iran. Objectives: This study aimed to determine the indigenous plants used for the treatment of diabetes in Shiraz, southwest of Iran. Materials and Methods: Semi–structured direct interviews were conducted with 25 herbalists to identify medicinal plants used to treat diabetes. Questionnaires were included herbalist personal information, plant local name, growth season, plant parts used, preparation methods, and traditional therapies. Results: The interview data indicated that, 24 medicinal plants from 19 families are used for the treatment of diabetes in Shiraz. The families with most antidiabetic species were Compositae (13%), Rosaceae (13%) and Cucurbitaceae (8%). The most frequently used plant parts were fruits (38%) and the most common preparation method was decoction (62%). For 45% of reported plants, pharmaceutical studies approved antidiabetic effects in animal or humane model of diabetes. Results of this study showed that the plants recommended by Shirazian herbalists have potential antidiabetic effects. Conclusions: It is suggested that the ingredients of indigenous plants be studied to determine therapeutic effects and mechanism of action. If they were safe and effective, they can be refined and processed to produce natural drugs.

۲۰Rocking Rotation of a Rigid Disk Embedded in a Transversely Isotropic Half–Space
نویسنده(ها): ، ، ،
اطلاعات انتشار: Civil Engineerng Infrastructures Journal، دورهجدید،چهل و هفتم،شماره۱، Jun ۲۰۱۴، سال
تعداد صفحات: ۱۴
The asymmetric problem of rocking rotation of a circular rigid disk embedded in a finite depth of a transversely isotropic half–space is analytically addressed. The rigid disk is assumed to be in frictionless contact with the elastic half–space. By virtue of appropriate Green's functions, the mixed boundary value problem is written as a dual integral equation. Employing further mathematical techniques, the integral equation is reduced to a well–known Fredholm integral equation of the second kind. The results related to the contact stress distribution across the disk region and the equivalent rocking stiffness of the system are expressed in terms of the solution of the obtained Fredholm integral equation. When the rigid disk is located on the surface or at the remote boundary, the exact closed–form solutions are presented. For verification purposes, the limiting case of an isotropic half–space is considered and the results are verified with those available in the literature. The jump behavior in the results at the edge of the rigid disk for the case of an infinitesimal embedment is highlighted analytically for the first time. Selected numerical results are depicted for the contact stress distribution across the disk region, rocking stiffness of the system, normal stress, and displacement components along the radial axis. Moreover, effects of anisotropy on the rocking stiffness factor are discussed in detail.

۲۱The effect of salinity stress on Na+, K+ concentration, Na+\K+ ratio, electrolyte leakage and HKT expression profile in roots of Aeluropus littoralis
اطلاعات انتشار: Journal of Plant Molecular Breeding، سوم،شماره۲، ۲۰۱۵، سال
تعداد صفحات: ۱۰
Among abiotic stresses, salinity has been increasing over the time for many reasons like using chemical fertilizers, global warming and rising sea levels. Under salinity stress, the loss of water availability, toxicity of Na+ and ion imbalance directly reduces carbon fixation and biomass production in plants. K+ is a major agent that can counteract Na+ stresses, thus the potential of plants to tolerate salinity is strongly dependent on their potassium nutrition. HKTs (High–affinity K+ Transporters) are a family of transporters that mediate Na+–specific or Na+–K+ transport and play a key role in the regulation of ion homeostasis. In this study, we intended to focus on Electrolyte Leakage, ratio of K+\Na+, transcriptomic responses of a subclass two HKT in the roots of Aeluropus littoralis under salt stress. We investigated a noticeably different expression pattern over studied time points and found a snappy increase of AlHKT and rebalance of K+ concentration. It can be suggested that the early and high response of a Na+–K+ coupled transporter acted as a part of A. littoralis salt tolerance.

۲۲The responses of L–gulonolactone oxidase and HKT2;1 genes in Aeluropus littoralis’ shoots under high concentration of sodium chloride
اطلاعات انتشار: Journal of Plant Molecular Breeding، سوم،شماره۲، ۲۰۱۵، سال
تعداد صفحات: ۸
Salinity is one of the most important abiotic stresses that limit crop growth and production. Salt stress influences plants in two ways: by affecting ion toxicity and increasing osmotic stress. Ion homeostasis, the excretion of Na+ and using antioxidant systems are the major strategies of salt tolerance in plants. Na+ and K+ transporters with enzymes that are involved in detoxification of reactive oxygen species play key roles in salt tolerance in plants. The aim of this study was to investigate the responses of high affinity K+ transporter2;1 gene (HKT2;1) which is involved in regulation of ion homeostasis and L–gulonolactone oxidase (GLOase) which is involved in the ascorbic acid biosynthesis pathway, under different concentrations of NaCl over different time points in Aeluropus littoralis shoots. Results from Real Time PCR data showed that expressions of both genes were influenced by external and internal concentrations of Na+ and the internal K+ content. AlHKT2;1 was significantly upregulated by increasing Na+ concentration at all time points. Furthermore, its highest expression level in shoots occurred after 6 days in 300mM NaCl in shoots which was 25folds more than untreated shoots. AlGLOase expression levels increased 54 h after initiation of salt stress. These results indicate that AlHKT2;1 and AlGLOase respond to different salinity conditions and probably are part of the mechanisms involved in tolerance to high salt concentrations in A. littoralis.

۲۳Regional model presentation for peak discharge estimation in ungauged drainage basin using geomorphologic, Synyder, SCS and triangular models (case study: Kan drainage basin)
نویسنده(ها): ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Caspian Journal of Environmental Sciences، دهم،شماره۱، ۲۰۱۲، سال
تعداد صفحات: ۱۲
With regard to the importance of instantaneous peak discharge estimation for watershed management study, and due to the lack of and unqualified climatic and hydrologic data for estimation and measurement in countries such as Iran, researchers were obliged to establish a link between constant parameters (geomorphologic) and variables (hydrologic) to present models with minimum dependence on climatic and hydrologic data in hydrologic estimations. This research has made an effort to use synthetic unit hydrographs at the drainage basin of Kan (Soleghan River) and to compare these results with recorded peak discharge at the watershed outlet, in order to derive the best model. Comparison of study models using relative mean error (RME) and root of mean square error (RMSE) in the study drainage basin located in central Alborz watershed showed that RME for the Geomorphologic model was 17.99 and RMSE was 15.49, for Snyder RME was 59.66, and RMSE was 29.83, for SCS RME was 162.63 and RMSE was 76.002 and finally triangular RME was 165.82 and RMSE was 77.44. Therefore the best estimation belonged to the Geomorphologic model followed by the Snyder, SCS and Triangular models. Owing to the lack of recorded instantaneous peak discharges in the hydrometric station of the Kan drainage basin (11 events) at Kan–Soleghan, we are not able to derive an instantaneous peak discharge model. Hence by using factors in each of the studied models, other effective factors and 283 recorded events of daily peak discharges, the daily peak discharge model can be derived.
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