توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Bernoulli polynomials of the second kind and their identities arising from umbral calculus
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۱۰
In this paper, we study the Bernoulli polynomials of the second kind with umbral calculus viewpoint and derive various identities involving those polynomials by using umbral calculus.

۲Lagrangians of the (2 + 1)–dimensional KP equation with variable coefficients and cross terms
نویسنده(ها): ، ، ، ، ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۳
Zhang constructed a Lagrangian for the (2 + 1)–dimensional KP equation with variable coefficients and cross terms [L. H. Zhang, Appl. Math. Comput., 219 (2013), 4865–4879]. This paper suggests a simple method to construct a needed Lagrangian using the semi–inverse by introducing a simple auxiliary function, the presented method is simpler than Zhang’s method to construct a Lagrangian.

۳On the multilevel nonlinear problem and its convergence algorithms
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۱۴
In this paper, applying the geometrical knowledge of Hilbert spaces, we investigate and analyze a system of multilevel split fixed point problems (MSFP). New split solution algorithms are introduced and strong convergence theorems for (MSFP) are established. At the end of this paper, as an application of our results, we investigate and analyze a system of multilevel split variational inclusion problems (MSVIP) and some strong convergence solution for (MSVIP) are obtained. These results obtained by this paper improve and develop some known ones in the literature.

۴Monotone projection algorithms for various nonlinear problems in Hilbert spaces
نویسنده(ها): ، ، ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۱۰
In this paper, a monotone projection algorithm is investigated for solving common solutions of a fixed point problem of an asymptotically strict pseudocontraction, an equilibrium problem and a zero problem of the sum of two monotone mappings. Strong convergence theorems are established in the framework of real Hilbert spaces.

۵The dynamics and solution of some difference equations
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۱۲
In this paper, we study solution and periodic nature of the following difference equationsxn+1 = xn−1xn−5 xn−3(±1±xn−1xn−5) , n = 0,1,..., where the initial conditions x−5, x−4, x−3, x−2, x−1, x0 are arbitrary positive real numbers. we studied the equilibrium points of the given equation. Some qualitative properties such as the global stability, and the periodic character of the solutions in each case have been studied. We presented some numerical examples by using random initial values and the coefficients of each case. Some figures have been given to explain the behavior of the obtained solutions by using MATLAB to confirm the obtained results. c2016 All rights reserved.

۶Full state hybrid projective synchronization of variable–order fractional chaotic\hyperchaotic systems with nonlinear external disturbances and unknown parameters
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۱۳
The full state hybrid projective synchronization (FSHPS) definition for variable–order fractional chaotic\hyperchaotic systems with nonlinear external disturbances and unknown parameters is firstly presented. Then by introducing a compensator and a nonlinear controller, the FSHPS scheme is generated to eliminate the influence of nonlinear external disturbances effectively. Moreover, the parameters are estimated validly. Based on these control methods, appropriate parameters and controller to achieve FSHPS for the variable–order fractional chaotic\hyperchaotic systems are chosen impactfully. Simulations of variable–order fractional Chen and Lu¨ system and fractional order hyperchaotic Lorenz system in the sense of FSHPS are performed and results show the effectiveness of our method.

۷ositive solutions for m–point boundary value problem
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۹
In this paper, we study the existence of positive solutions for the following nonlinear m–point boundary value problem for an increasing homeomorphism and homomorphism with sign changing nonlinearity: (φ(u0))0 + a(t)f(t,u(t)) = 0, 0 t 1, u0(0) = m−2 P i=1 aiu0(ξi), u(1) = k P i=1 biu(ξi)− s Pi =k+1 biu(ξi)− m−2 Pi =s+1 biu0(ξi), where φ : R −→ R is an increasing homeomorphism and homomorphism and φ(0) = 0. The nonlinear term f may change sign. As an application, an example to demonstrate our results has given. The conclusions in this paper essentially extend and improve the known results.

۸Inverse problems for a nonlocal wave equation with an involution perturbation
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۹
Two inverse problems for the wave equation with involution are considered. Results on existence and uniqueness of solutions of these problems are presented.

۹Difference–genetic co–evolutionary algorithm for nonlinear mixed integer programming problems
نویسنده(ها): ، ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۲۴
In this paper, the difference genetic co–evolutionary algorithm (D–GCE) is proposed for the mixed integer programming problems. First, the mixed integer programming problem with constrains converted to unconstrained bi–objective optimization problems. Secondly, selection mechanism combines the Pareto dominance and superiority of feasible solution methods to choose the excellent individual as the next generation. Final, differential evolution algorithm and genetic algorithm handle the continuous part and discrete part, respectively. Numerical experiments on 24 test functions have shown that the new approach is efficient. The comparison results among the D–GCE and other evolutionary algorithms indicate that the proposed D–GCE algorithm is competitive with and in some cases superior to, other existing algorithms in terms of the quality, efficiency, convergence rate, and robustness of the final solution.

۱۰Local conjugacy theorems for C1 operators between Banach manifolds
نویسنده(ها): ، ،
اطلاعات انتشار: Journal of Nonlinear Sciences and Applications، نهم،شماره۳، ۲۰۱۶، سال
تعداد صفحات: ۸
In this paper, by the generalized inverse theory of bounded linear operators, the local conjugacy theorem for C1 operators between Banach manifolds is established. According to this theorem, the conditions which can be used to make sure that a C1 operator can be linearized are provided. Local conjugacy theorems for nonlinear Fredholm operators, nonlinear semi–Fredholm operators and finite rank operators are introduced. c2016 All rights reserved.

۱۱Contemporary and sub–fossil house mice (Mus musculus Linnaeus, 1758) (Rodentia: Muridae) from Iran
نویسنده(ها): ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: Iranian journal of animal biosystematics، ششم،شماره۲، ۲۰۱۰، سال
تعداد صفحات: ۱۰
The house mouse (Mus musculus) is a polytypic species, with its geographic distribution largely the result of human migrations during the Late Glacial and Holocene. This study used geometric morphometry (GM) on upper and lower molars to discriminate among the three subspecies of the house mouse present in Iran. Moreover cranial remains of this species were uncovered on several archaeological sites of the Iranian Plateau. The GM results were applied to sub–fossil lower molars from Isfahan (Qaleh Bozi), Kordestan (Kani Mikaiil), Qazvin (Zagheh), and Jiroft (Konar Sandal). The present–day Iranian populations that have been previously separated into three subspecies (M. musculus musculus, M. musculus domesticus, and pro–castaneus type) by molecular studies can also be distinguished by dental geometric morphometrics. These subspecies are distinguished by variation in the shape of the first and second upper molar (M1\, M2\) and the first lower molar (M\1). Comparison of these results to the Late Glacial\Early Holocene material from the above mentioned fossil bearing localities shows marked similarity with the extant house mouse of the southeastern Iranian Plateau, the pro–castaneus type.

۱۲Karyologic study of three species of Calomyscus (Rodentia: Calomyscidae) from Iran
نویسنده(ها): ، ، ، ،
اطلاعات انتشار: Iranian journal of animal biosystematics، ششم،شماره۲، ۲۰۱۰، سال
تعداد صفحات: ۶
The genus Calomyscus has long been considered monotypic and represented by the species C. bailwardi. Finally in the most recent revision, eight geographic species were recognized: C. bailwardi, C. baluchi, C. elburzensis, C. grandis, C. hotsoni, C. mystax, C. tsolovi, and C. urartensis. Since the taxonomic status of this genus remains somewhat controversial, karyological analysis may provide important information for evaluating the systematic position of Calomyscus. So far, within the range of the genus Calomyscus several distinct karyotypes have been identified. The karyotype of C. hotsoni has been undocumented until now but its karyotype recorded in this study from vicinity of type locality, Sistan va Baluchistan Province in the south eastern of Iran that was different with the karyotype of another species in this genus. Furthermore, three new karyotypes of Calomyscus were studied by conventional staining technique from Khorasan and Yazd Provinces of Iran that represent chromosomal variations in this genus. Chromosome studies show that Calomyscus specimens from Yazd Province should be belong to C. elburzensis. But more karyological, molecular and morphological studies would be necessary for confirming this decision.

۱۳First record of Zarudny’s Jird, Meriones zarudnyi Heptner, 1937 (Rodentia: Muridae) in Shirvan, Northeast Iran (Text in Persian)
نویسنده(ها): ، ، ، ، ،
اطلاعات انتشار: Iranian journal of animal biosystematics، ششم،شماره۲، ۲۰۱۰، سال
تعداد صفحات: ۱۱
Among the rodent specimens deposited in the collections of Rodentology Research Department at Ferdowsi University of Mashhad، one specimen of Zarudny’s Jird was found which has been collected from Shirvan، in Northern Khorasan Province، Iran. This species is a new record for the fauna of Iran. The species Meriones zarudnyi Heptner، 1937 was recorded for the first time from Kushka in Turkmenistan (Fig.1A) and is distributed in the arid steppes of northern Afghanistan and southern Turkmenistan (Musser & Carleton، 2005). Meriones zarudnyi is endemic in the Badkhiz region of southern Turkmenistan (semi–arid highland habitats)، but has not been reported in the Iranian Plateau. Meriones zarudnyi was considered a race of M. crassus by Ellerman & Morrison–Scotte (1966). Kuznetsov (1965) tentatively treated it as a distinct species، while Lay (1972)، based on additional evidence from Afghanistan، emphasized that it was distinct from both M. crassus and M. tristrami. The presence of this species in Afghanistan was confirmed by Hassinger (1973) who stated that M. zarudnyi is restricted to Turkmenistan and Afghanistan. The studied specimen collected from the Shirvan confirmed that this species is widely distributed towards W of Turkmenistan and NE of Iran. The diagnostic characters of M. zarudnyi are ambiguous and overlap with those of other species of Meriones; its distinction from other Meriones species is difficult and a detailed study of external and cranial morphology of this species might be appropriate. This species differs from M. tristrami in having a hairy hind foot. The underbelly is white; the upper part of the tail light gray and its lower part yellowish; the tail is longer than the head and body; the tuft of the tail is well developed as in M. persicus، and its proximal part is off–white in both the upper and lower areas and the extremity short، dark brown to maroon dark yellow. The sole of the hind foot is partially covered with fur and the heel is bare. Claws are yellow and its upper part is a mixture of brown and chestnut color with a tendency towards a dark sand–like color. The auditory bulla is remarkably similar to M. persicus، but its posterior edges are flattened (Fig. 1B). The auditory meatus lacks a curtain، is flat with the anterior edge of the meatus slightly curved; the suprameatal triangle is large، isosceles، and closed. Suprameatal space is large with an upper empty half. The upper part of the suprameatal triangle is equal to the lower suprameatal process. Zygomatic plate is rectilinear (Vinogradov & Argyrupola، 1968). Material examined: Zoological Museum، Ferdowsi University of Mashhad (ZMFUM–2288) (Skull، skin and tissue)، adult male، Shirvan (37° 36΄N، 57° 42΄E، 1089 m)، Northern Khorasan Province، Iran، 2011، leg. A. Mahmoodi. Morphometric data of material examined is given in Table 1.

۱۴Improving Competitive Advantage with Environmental Infrastructure Sharing: A Case Study of China–Singapore Suzhou Industrial Park
نویسنده(ها): ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، چهارم،شماره۴، Autumn۲۰۱۰، سال
تعداد صفحات: ۸
As one way to approach industrial symbiosis, environmental infrastructure sharing is principally concerned with providing an integrated environmental utility system for clustered firms. It is based on the assumption that environmental infrastructure sharing can improve the regional competitive advantage by reducing overall cost and improving environmental performance. In order to verify the assumption, the research examines the cost–effectiveness of wastewater treatment system of China–Singapore Suzhou Industrial Park between the isolated model and sharing one. The results show that the sharing mode can greatly reduce the overall cost and furthermore provide competitive advantage comparing to the isolated one. In addition, it also improves the overall environmental performance and enforces the cooperation among clustered companies, which creates a good integrated image and attracts more and more excellent enterprises to join in.

۱۵Equilibrium and Kinetic Studies on Sorption of Malachite Green using Hydrilla Verticillata Biomass
نویسنده(ها): ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، چهارم،شماره۴، Autumn۲۰۱۰، سال
تعداد صفحات: ۸
In the present study, Hydrilla verticillata biomass was investigated as a novel biosorbent for the uptake of basic dye malachite green from its aqueous solution. Kinetic and equilibrium studies were carried out in batch process. Batch adsorption experiments were conducted to study the effect of pH, temperature, sorbent dosage, initial dye concentration, and contact time for the removal malachite green dye. The dye uptake was maximum for the initial pH of 8, temperature of 30oC, sorbent dosage of 0.55g, initial dye concentration 200mg\l and contact time – 150 min. The kinetic studies were well modeled using pseudo first order and second order with isotherm studies.

۱۶Trihalomethanes Concentration in Different Components of WaterTreatment Plant and Water Distribution System in the North of Iran
نویسنده(ها): ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، چهارم،شماره۴، Autumn۲۰۱۰، سال
تعداد صفحات: ۶
Since the surface water is one of the main potable water resources, the usage of chlorine as a disinfectant has increased. Consequently the production rate of disinfection by–products (DBPs) such as Trihalomethane (THM) compounds has grown dramatically. In this paper the THMS concentration changes in the Sangar Water Treatment Plant (SWTP) and Rasht Water Distribution System (RWDS) is presented. The duration of these monitoring tasks were 6 months in 2007 and samples were collected every 2 weeks. Water samples were collected from five locations at SWTP and RWDS. Some independent variables including Total Organic Carbon (TOC), pH, temperature, and residual chlorine were measured by Pearson method to find a relation between THMS formation and these variables. In the case of TOC, Pearson method showed a correlation of r = 0.8096 for SWTP and r = 0.3696 for RWDS between THM formation and TOC. Also the relationship for SWTP was r = 0.239 and r = 0.2336 for RWDS between THM formation and temperature. Correlation between THM formation and pH, Pearson method showed r = 0.4658 for SWTP and r = 0.3232 for RWDS. In the case of residual chlorine, Pearson method showed a relationship of r = 0.7354 for SWTP and r = 0.5623 for RWDS. Results proved a direct relation between THMS concentration and distance of chlorination injection points. The results showed that in SWTP, 42.7 percent of THM compounds were removed after sedimentation and filtration.

۱۷A Genotoxicological Study in Persian Gulf on Rock Oyster (Soccostrea cucullata) using Micronuclei and RAPID Assays
نویسنده(ها): ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، پنجم،شماره۲، Spring ۲۰۱۱، سال
تعداد صفحات: ۶
Both micronuclei (MN) and binuclei (BN) as well as RAPD (Random Amplifying Polymorphism of DNA) assays are newly biomarkers which are well–introduced in toxic injury and related genotoxicity studies in bivalve, fishes and even humans. However, there is no record of such studies in Iranian Persian Gulf coast line so far. For this propose, we analyzed frequency of MN and RAPD patterns in gill cells of rock oyster (soccostrea cucullata) (n=30) collected from two area including Dayer (as reference area) and Mahshahr which was already shown oil contaminant are relatively high in this area owing to be oil vessel terminal. Our results showed micronuclei frequency is significantly higher in rock oysters of Mahshahr than Dayer area (p0.05). Binuclei cells were also observed in some individuals of Mahshahr. Besides, RAPD analysis indicated less diversity in polluted area individuals. The results of this study suggest that MN and RAPD analyses can be easily considered as a useful tool for assessment of diverse pollution on aquatic organism in coastal area of Persian Gulf.

۱۸Impact of a Mixed Industrial and Domestic Wastewater Effluent on the Southern Coastal Sediments of Sfax (Tunisia) in the Mediterranean Sea
نویسنده(ها): ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، پنجم،شماره۳، Summer ۲۰۱۱، سال
تعداد صفحات: ۱۴
Concentrations of Zn, Cu, Cr, Cd, Pb and Fe in surface marine sediments of the southern coast of Sfax were studied in order to understand current metal contamination at the outlet of a mixed industrial and domestic wastewater effluent discharged into the seawater since 1953. We found that heavy metal concentrations (mg\kg dry weight) in surface marine sediments varied from 42 to 391 for Zn, 15 to 44 for Cu, 44 to 137 for Cr, 6 to 56 for Cd, 19 to 59 for Pb and 52344 to 54543 for Fe. The computed metal enrichment factors (EF) in the sediments showed that EF of Zn ranged from 0.49 to 9.13, EF of Cu from 0.35 to 3.04, EF of Cr from 0.3 to 3.05, EF of Cd from 0.63 to 9.37 and EF of Pb from 0.43 to 3. All heavy metals were characterized by maxima EF values greater than 1.5, indicating a considerable metallic pollution of the study area. The PCA analysis revealed two distinct groups: (i) the first group (G1) is representative of Fe selected as natural tracer and (ii) the second group (G2) is articulated around Zn, Cu, Cr, Cd and Pb. These metals which did not show any correlations with Fe of the first group imply a significantly impact of the selected wastewater effluent. The calculation of the geoaccumulation index (Igeo) showed that all analyzed metals (except for Fe) can be considered as moderate to extreme pollutants. The microbial analysis of seawater samples and also of both water and sediment samples collected from the Sfax solar saltern (placed at the vicinity of the outlet of the selected effluent) showed that no indicator germs of contamination (total coliforms, faecal coliforms and faecal streptococci) were detected.

۱۹Improved Analytical Extraction and Clean–up Techniques for the Determination of PAHs in Contaminated Soil Samples
نویسنده(ها): ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، پنجم،شماره۳، Summer ۲۰۱۱، سال
تعداد صفحات: ۱۰
Development and optimisation of fast, efficient, quantitative, economic and environmentally friendly analytical extraction techniques for the extraction clean up, and pre–concentration in the quantification of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in contaminated soils have been carried out. Three different extraction methods (Soxhlet, ultra sonication and mechanical shaking) were investigated on a low–level PAH soil certified reference material (CRM131–100) and the results were compared to determine the technique with the highest extraction efficiency. The clean up and pre–concentration procedures were optimized using both the conventional method (i.e. column packing with silica gel) as well as the solid phase extraction (SPE). Chromatographic conditions for the separation of PAHs using High Performance Liquid Chromatography (HPLC) using UV–DAD and fluorimetric detection with programmed excitation and emission wavelengths were also optimized. Six different extraction solvents: acetone, cyclohexane, 2– propanol, methanol, acetonitrile and dichloromethane, were tested to select the most suitable solvent for the extraction of the 16 PAHs from the certified soil reference material. Acetonitrile, dichloromethane and tetrahydrofuran were also tested as eluants for the optimisation of SPE clean up. The optimized ultrasonic extraction procedure utilizing four 15 minutes extraction cycles at 50 ºC and SPE clean up with tetrahydrofuran: acetonitrile (1:1) and subsequent separation by gradient reversed phase HPLC with fluorimetric detection extracted the PAHs from the certified reference material with recoveries ranging from 63.6 % to over 100 % .

۲۰Assessment of Ecological integrity in a landscape context using the Miankale peninsula of Northern Iran
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، ششم،شماره۲، Spring ۲۰۱۲، سال
تعداد صفحات: ۸
Identification of rapid degradation of ecological resources requires effective environmental monitoring including ecological integrity assessment .Our first aim is to analyze ecological integrity in a landscape context while developing a method to assess integrity in spite of a dearth of historical data. We used a Spatial–Temporal Reference Framework for land cover maps for assessing ecological integrity change, emphasizing changes in patch types and configuration. Land cover is used as a surrogate for habitat. Habitat condition is the main point of this research in assessing ecological integrity. Our second aim is to recognize, through a case study of the above, the ecological integrity of the Miankale peninsula of Miankale Biosphere Reserve on Iran’s Caspian Sea coast in the east latitude of 53 ،24 ،50ً and north altitude of 36 ،56 ،45ً . Land cover data were obtained from Landsat TM5 of 1985 and compared with current condition images from Landsat TM5 of 2010. Landscape metrics show that Minakale’s natural semi–dense shrub lands are fragmented; with the number of patches increasing and average patch area decreasing. This implies a fall in habitat available to its dependent bird species. In conclusion, considering birds’ habitat and its aggregation as a measure of integrity, landscape metrics show ecological integrity of Miankale has decreased and signals of habitat loss have appeared in study area. More detailed analysis in ecosystem scale is suggested as the complementary research to find the best indicator for assessing the integrity of the ecosystem.

۲۱Accumulation of PAHs,Me–PAHs, PCBs and totalMercury in sediments andMarine Species in CoastalAreas ofDakar, Senegal: Contamination level and impact
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، نهم،شماره۲، Spring ۲۰۱۵، سال
تعداد صفحات: ۱۴
Persistent Organic Pollutants (POPs) have widely aroused public concern due to their ubiquity, environmental persistence, long–range transportability, bioaccumulation capacities and potentially adverse effects on living organisms. Dakar is located in the industrial zone of Senegal (80% of industrial activities) and inhabits 25% of Senegalese population leading to an ideal sink of these persistent organic pollutants. In the present paper, Polychlorinated Biphenyls (PCBs) and polycyclicAromatic Hydrocarbons (PAHs) were analyzed in sediments and marine organisms. The contamination level of PAHs,Me–PAHs and PCBs in surface sediment and aquatic organisms (one macroalgae, two invertebrate species, four fish species and macroalgae) were determined. The concentration levels in the sediment were detected from 2 to 636 μg\kg dw for Σ16PAHs, from 3 to 3 μg\kgdw for Σ18Me–PAHs and from 4 to 333 μg\kg dw for Σ28PCBs for the selected stations in Dakar costal area. PAHs concentrations determined in edible tissues were lower than sediment samples. Tilapia species present the highest mean levels of PAHs and Me–PAHs at 92 ± 54 and 183 ± 39 μg\kg dw respectively. For PCBs, the highest level was determined in Perna perna species (up to 1228 μg\kg dw) and the lowest level was found in Penaeus kerathurus species. At the base of the food chain, Ulvalactula species displayed low PCB concentrations detected at 7 ± 6 μg\kg dw. The totalmercury concentration was also reported in this paper in order to complete the background of pollution degree and to study the potential processes of biomagnification and\or bioaccumulation of contaminants in marine food chain. Mercury concentration were detected in the sediment ranging from 5 to 95 μg\kg dw. For marine species, considering all organisms, the mean concentration of mercury varies between 5 and 442 μg\kg dw. Pyrogenic process was the predominant source of PAHs contamination in our sampling sites. Based on Sediments Quality Guidelines (ERM–ERL\TEL–PEL approaches) rare biological adverse effects of total mercury, PCBs and PAHs on aquatic ecosystems were expected in Dakar coastal area. Finally, in the context of human health, the edible marine species qualities obtained from three stations of Dakar coastal areas have been also evaluated. Based on the European Union legislation, the selected species present good quality for human consumption based on PCBs, PAHs and mercury.

۲۲GroundwaterTreatment using the Fenton process: Changes in Natural OrganicMatterCharacteristics andArsenic Removal
نویسنده(ها): ، ، ، ، ، ، ، ، ، ، ، ، ،
اطلاعات انتشار: International Journal Of Environmental Research، نهم،شماره۲، Spring ۲۰۱۵، سال
تعداد صفحات: ۸
This work investigates the use of Fenton’s process (pH 5.5 and 6; 0.10–0.50 mM Fe(II); molar ratios Fe(II) to H2O2 of 1:5–1:20) combined with flocculation for the treatment of groundwater which is rich in natural organic matter (NOM) (10.6±0.37 mg C\L) and arsenic (110±6.7 μg\L). Changes to the character of the residual NOM fractions were followed, as well as the removal efficiencies of NOM and arsenic. Under optimal reaction conditions at pH 5.5, 55% of theDissolvedOrganic Carbon (DOC) was removed, whilst removals of specific disinfection by–product precursors of trihalomethanes (THM), haloacetic acids (HAA) and haloacetonitriles (HAN) were 80%, 75% and 98%, respectively. Total arsenic concentrations were reduced to below 5 μg\L under all investigated experimental conditions. After the Fenton treatment, the percentage of the hydrophobic NOMfraction (humic acid and fulvic acid fraction) decreased, and the percentage of the hydrophilic fraction (acidic and non–acidic fractions) increased. The hydrophilic fraction, which was the most abundant in the treated water, was also the most reactive fraction towards THM and HAA formation, whereas the residual fulvic acid fraction contributed the most to the formation of HAN.

۲۳Determination of Stability Domains for Nonlinear Dynamical Systems Using the Weighted Residuals Method
نویسنده(ها): ، ، ،
اطلاعات انتشار: Civil Engineerng Infrastructures Journal، چهل و ششم،شماره۱، Jan ۲۰۱۳، سال
تعداد صفحات: ۲۴
Finding a suitable estimation of stability domain around stable equilibrium points is an important issue in the study of nonlinear dynamical systems. This paper intends to apply a set of analytical–numerical methods to estimate the region of attraction for autonomous nonlinear systems. In mechanical and structural engineering, autonomous systems could be found in large deformation problems or control of structures. In order to have an appropriate estimation of stability domain, some suitable Lyapunov functions are calculated by satisfying the modified Zubov''s partial differential equation in a finite area around the asymptotically stable equilibrium point. To achieve this, the techniques of Collocation, Galerkin, Least squares, Moments and Sub–domain are applied. Furthermore, a number of numerical examples are solved by the suggested techniques and Zubov''s construction procedure. In most cases, the proposed approaches compared with Zubov’s scheme give a better estimation stability domain.

۲۴An Enhanced HL–RF Method for the Computation of Structural Failure Probability Based On Relaxed Approach
نویسنده(ها): ، ، ،
اطلاعات انتشار: Civil Engineerng Infrastructures Journal، چهل و ششم،شماره۱، Jan ۲۰۱۳، سال
تعداد صفحات: ۱۲
The computation of structural failure probability is vital importance in the reliability analysis and may be carried out on the basis of the first–order reliability method using various mathematical iterative approaches such as Hasofer–Lind and Rackwitz–Fiessler (HL–RF). This method may not converge in complicated problems and nonlinear limit state functions, which usually shows itself in the form of periodic, bifurcation and chaos solution. In this paper, the HL–RF method has been improved based on the relaxed method to overcome these numerical instabilities. An appropriate relaxed coefficient has been defined, ranging between 0 and 1, to enhance the HL–RF method. This coefficient can be computed using the information from the new and previous iterations of the HL–RF algorithm based on second–order fitting. Capability, robustness and efficiency of the proposed algorithm have been studied by results of several examples compared to the HL–RF. Results illustrated that the proposed method is more efficient and robust in the computation of the failure probability compared to the HL–RF method.

۲۵Automatic Calibration of HEC–HMS Model Using Multi–Objective Fuzzy Optimal Models
نویسنده(ها): ، ، ،
اطلاعات انتشار: Civil Engineerng Infrastructures Journal، دورهجدید،چهل و هفتم،شماره۱، Jun ۲۰۱۴، سال
تعداد صفحات: ۱۲
Estimation of parameters of a hydrologic model is undertaken using a procedure called “calibration” in order to obtain predictions as close as possible to observed values. This study aimed to use the particle swarm optimization (PSO) algorithm for automatic calibration of the HEC–HMS hydrologic model, which includes a library of different event–based models for simulating the rainfall–runoff process. Since a flood hydrograph has different characteristics such as time to peak, peak discharge and total runoff volume, the calibration process is addressed using a single–objective or multi–objective optimization model. In this context, the fuzzy set theory can be used to combine different objective functions and convert the multi–objective model to a single–objective one. In this research, the Tamar basin, a sub–basin of the Golestan–Dam Basin in north of Iran, was selected as the case study with four reliable measured flood events. The first three events were used for calibration and the fourth one for verification. As most of the models built in the HEC–HMS software were event–based, the concept of recalibration of parameters related to a basin initial condition was also introduced. The comparison of results obtained from the single and multi–objective scenarios showed the efficiency of the proposed HMS–PSO simulation–optimization approach in the multi–objective calibration of event–based hydrologic models.
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