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Computer Modeling in Engineering & Sciences 2021年第11期129卷 927-951页

作者： mohammad fallah Hamed Nozari Department of Industrial Engineering Islamic Azad UniversityCentral Tehran BranchTehranIran

In this paper,a multi-objective sustainable biomass supply chain network under uncertainty is designed by neutrosophic programming *** this method,for each objective function of the problem,three functions of truth membership,non-determination and falsehood are *** programming method in this paper simultaneously seeks to optimize the total costs of the supply chain network,the amount of greenhouse gas emissions,the number of potential people hired and the time of product transfer along the supply chain *** achieve the stated objective functions,strategic decisions such as locating potential facilities and tactical decisions such as optimal product flow allocation and vehicle routing must be *** results of the implementation of neutrosophic programming method show the high efficiency of this method in achieving the optimal values of each objective ***,by examining the rate of uncertainty,it was observed that with increasing this rate,the total costs of supply chain network design,greenhouse gas emissions and product transfer times have increased,and in contrast,the potential employment rate of individuals has decreased.

关键词： Neutrosophic mathematical programming sustainable supply chain biomass supply chain neutrosophic set uncertainty

A Two-Stage Scenario-Based Robust Optimization Model and a Column-Row Generation Method for Integrated Aircraft Maintenance-Routing and Crew Rostering

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Computer Modeling in Engineering & Sciences 2024年第11期141卷 1275-1304页

作者： Khalilallah Memarzadeh Hamed Kazemipoor mohammad fallah Babak Farhang Moghaddam Department of Industrial Engineering Central Tehran BranchIslamic Azad UniversityTehran***Iran Institute for Management and Planning Studies Tehran***Iran

Motivated by a critical issue of airline planning process,this paper addresses a new two-stage scenario-based robust optimization in operational airline planning to cope with uncertainty and possible flight *** the route network scheme and generated flight timetables,aircraft maintenance routing and crew scheduling are critical factors in airline planning and operations cost *** study considers the simultaneous assignment of aircraft fleet and crew to the scheduled flight while satisfying a set of operational constraints,rules,and *** multiple locations for airline maintenance and crew bases,we solve the problem of integrated Aircraft Maintenance Routing and Crew Rostering(AMRCR)to achieve the minimum airline *** real challenge to the efficiency of the planning results is the possible disruptions in the initial scheduled *** to the fact that disruption scenarios are expressed discretely with a specified probability,and we provide adjustable decisions under disruption to deal with this disruption risk,we provide a Two-Stage Scenario-Based Robust Optimization(TSRO)*** this model,here-and-now or first-stage variables are the initial resource ***,to adapt itself to different disruption scenarios,the model considers some adjustable variables,such as the decision to cancel the flight in case of disruption,as wait-and-see or second-stage *** the complexity of integrated models,and the scenario-based decomposable structure of the TRSO model to solve it with better computational performance,we apply the column and row generation(CRG)method that iteratively considers the disruption *** numerical results confirm the applicability of the proposed TSRO model in providing the AMRCR problem with an integrated and robust solution with an acceptable level of computational *** evaluate the proposed TSRO model,which solves the AMRCR problem in an integrated an

关键词： Aircraft maintenance routing crew scheduling rostering uncertainty,scenario-based robust optimization column and row generation

Prevalence and risk factors of avian influenza H9N2 among backyard birds in Iran in 2015

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Asian Pacific Journal of Tropical Medicine 2019年第12期12卷 559-564页

作者： mohammad Hossein fallah Mehrabadi Arash Ghalyanchilangeroudi mohammad Hasan Rabiee Farshad Tehrani Razi Vaccine and Serum Research Institute Agricultural ResearchEducation and Extension Organization(AREEO)TehranIran Department of Microbiology and Immunology Faculty of Veterinary MedicineUniversity of TehranTehranIran Division of Epidemiology&Zoonosis Department of Food Hygiene&Quality ControlFaculty of Veterinary MedicineUniversity of TehranTehranIran Department of Health and Management of Poultry Diseases Iranian Veterinary OrganizationTehranIran

Objective: To investigate the prevalence and the risk factors of H9 N2 avian influenza among backyard birds in Iran between October and November 2015. Methods: In this study, a total of 15 500 blood samples and 2 884 cloacal swab samples of backyard birds were collected in villages of Iran between October and November 2015. Then, serum samples were examined with the hemagluttination inhibition test and cloacal swab samples were pooled together and examined by RT-PCR. The samples that had serological titer ≥ 4(log2) and villages that had at least one seropositive sample were considered ***: Out of 559 villages, 526(94.10%) were seropositive for the infection. Among 15 500 serum samples, 7 468(48.18%) samples were seropositive for the infection. The seroprevalence according to species was 54.02% among chickens, 17.59 % among ducks, 18.73% among turkeys, 84.21% among pigeons and 12.15% among ostriches, partridges and pheasants. Based on molecular test, 3.04% villages were positive. The seroprevalence in hot and humid area was less than that in cold and humid area(P<0.05).Conclusions: H9 N2 avian influenza has high seroprevalence among backyard birds of Iran. Therefore, preventive measures such as biosecurity Practices and monitoring should be applied to reduce the prevalence.

关键词： Influenza H9N2 Iran Backyard birds

The Effect of Variable Stator on Performance of a Highly Loaded Tandem Axial Flow Compressor Stage

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Journal of Thermal Science 2016年第3期25卷 223-230页

作者： Hamzeh Eshraghi Masoud Boroomand Abolghasem M.Tousi mohammad Toude fallah Ali mohammadi Department of Aerospace Engineering and Centre of excellence on computational aerospace engineering Amirkabir University of Technology Nanotechnology Research and Application Center Sabanci University

Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds. Considering the high aerodynamic load effects and structural concerns in the design process, it is possible to obtain higher pressure ratios compared to conventional compressors. However, it must be noted that imposing higher aerodynamic loads results in higher loss coemcients and deteriorates the overall performance. To avoid the loss increase, the boundary layer quality must be studied carefully over the blade suction surface. Employment of advanced shaped airfoils （like CDAs）, slotted blades or other boundary layer control methods has helped the de- signers to use higher aerodynamic loads on compressor blades. Tandem cascade is a passive boundary layer control method, which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads. In fact, the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade＇s suction side. Also, in compari- son to the single blade stators, tandem variable stators have more degrees of freedom, and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance. In the current study, a 3D design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage. Following, this design is numerically investigated using a CFD code and the stage characteristic map is reported. Also, the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed. To validate the CFD method, another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

关键词： Compressor Stage Highly Loaded Performance Characteristic Tandem Variable Stator

Low gradient ascites: A seven-year course review

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World Journal of Gastroenterology 2005年第15期11卷 2337-2339页

作者： Fariborz Mansour-Ghanaei Afshin Shafaghi Amir-Hossein Bagherzadeh mohammad-Sadegh fallah Gastrointestinal and Liver Diseases Research Center (GLDRC)

AIM: To study the patients with low gradient ascites in hospitals of Guilan Province (northern Iran).METHODS: Patients admitted in hospitals of Guilan Province with low gradient ascites from 1993 to 2000 were enrolled in the study. Serum and ascitic fluid albumin levels were determined by biochemical reactions. The serum-ascitic albumin gradient (SAAG) less than 1.1 g/dL was considered low. Statistical analysis was performed with SPSS 9.0software and P＜0.05 was considered statistically ***: Of the 148 patients enrolled in the study, 72(48.6%) were males and 76 (51.4%) were females with a mean age of 59.03±13.54 years. Tuberculous peritonitis was the most frequent cause of low gradient ascites in 68 (45.9%). Other most frequent causes were cancer in 62 (41.9%), nephrotic syndrome in 9 (6%), pancreatitis in 6 (4%). Peritoneal cancer was found in 22 (35%),ovarian and gastric cancers were found in 14 (22.5%)and 12 (19.3%), respectively. All of which were the causes of ascites. The mean SAAG was 0.68±0.19 g/dL. The mean serum and ascitic fluid albumin concentrations were higher in tuberculous patients (P＜0.006), but lactate dehydrogenase (LDH) level was higher in cancer patients (P＜0.0001). In peritoneal tuberculosis, mean ascitic glucose concentration was significantly lower than other patients (P＜0.0001).CONCLUSION: Tuberculosis should be considered in all patients with low gradient ascites especially in developing countries (like Iran), as the first cause of ascites. In the approach to patients with low gradient ascites, ascitic fluid glucose, and LDH level are useful indicators for decision making.

关键词： Ascites Tuberculosis Cancer Albumin

Synthesis and Characterization of Nano-sized Zinc Oxide Coating on Cellulosic Fibers： Photoactivity and Flame-retardancy Study

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Chinese Journal of Chemistry 2011年第6期29卷 1239-1245页

作者： fallah, Moafi Hadi fallah, Shojaie Abdollah Zanianchi, mohammad Ali Department of Chemistry Faculty of Science University of Guilan P.O. Box 1914 Rasht Iran

We have investigated the effect of zinc oxide as a photocatalyst and durable flame-retardant on cellulosic fibers. Zinc oxide nanocrystals were successfully synthesized and deposited onto cellulosic fibers using sol-gel process at low temperature. The samples were characterized by means of several techniques such as scanning electron microscopy, transmission electron microscopy, diffuse reflectance spectroscopy, X-ray diffraction and thermogra- vimetric analysis. The photocatalytic activity was tested by measuring the photodegradation of methylene blue under UV-Vis illumination. Moreover, flame-retardancy was tested by vertical flame spread test. The optimum add-on value for donating flame-retardancy onto cellulosic fabric was obtained to be in the range of 15.24 to 23.20 g of the ZnO per 100 g of fabric. Thermogravimetric analysis of pure and flame-retarded samples were accomplished and discussed. The results obtained are in agreement with Wall effect theory and Coating theory. The originality of this work on introducing photoactive flame-retarded fibers is highly valuable for industrial implementation.

关键词： cellulosic fiber flame-retardancy photocatalytic self-cleaning zinc oxide coating nanoparticle sol-gel processes

Impact of land-use management on nitrogen transformation in a mountain forest ecosystem in the north of Iran

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Journal of Forestry Research 2013年第1期24卷 115-119页

作者： Maryam Asadiyan Seyed mohammad Hojjati mohammad reza Pourmajidian Asghar fallah Sari Agricultural Sciences and Natural Resources University Sari-Iran.

Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in soil N dynamics. This study was conducted to determine the soil inorganic N concentrations and net N mineralization rate in four common types of land-uses in the mountain forest area in the north of Iran, namely arable land, pine plantation, ash plantation, and beech stand. The soil samples were taken from top mineral soil layer （5 cm） in each site randomly （n=6） during August- September 2010. Beech stand and ash plantation showed significantly higher total nitrogen compared with arable land and pine plantation, while extractable NH4 ＋-N concentration was significantly greater in Beech stand compare to arable soils （p〈0.05）. No significantly difference was found in Net N mineralization, net nitrification and net ammonification rates among different land-uses. Results showed that net N mineralization and ammonification were occurred just in the soil of Ash plantation during the incubation time. Our findings suggested that conversion of Hyrcanian forests areas to pine plantation and agricultural land can disrupt soil natural activities and affect extremely soil quality.

关键词： soil quality net N mineralization nitrogen dynamic land use Hyrcanian forest Alandan.

Estimation of aboveground tree carbon stock using SPOT-HRG data (a case study: Darabkola forests)

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Journal of Forestry Research 2017年第6期28卷 1172-1179页

作者： Masoumeh Fatholahi Asghar fallah Seyed mohammad Hojjati Siavash Kalbi Department of Natural Resource Sari University of Agricultural Sciences and Natural Resources SariMazandaran 48151 Iran

Forests are among the most important carbon sinks on earth. However, their complex structure and vast areas preclude accurate estimation of forest carbon *** sets from forest monitoring using advanced satellite imagery are now used in international policy *** sets enable tracking of emissions of COinto the atmosphere caused by deforestation and other types of land-use changes. The aim of this study is to determine the capability of SPOT-HRG Satellite data to estimate aboveground carbon stock in a district of Darabkola research and training forest, Iran. Preprocessing to eliminate or reduce geometric error and atmospheric error were performed on the images. Using cluster sampling, 165 sample plots were taken. Of 165 plots, 81 were in natural habitats, and 84 were in forest plantations. Following the collection of ground data, biomass and carbon stocks were quantified for the sample plots on a per hectare basis. Nonparametric regression models such as support vector regression were used for modeling purposes with different kernels including linear, sigmoid, polynomial, and radial basis *** results showed that a third-degree polynomial was the best model for the entire studied areas having an root mean square error, bias and accuracy, respectively, of 38.41,5.31, and 62.2; 42.77, 16.58, and 57.3% for the best polynomial for natural forest; and 44.71, 2.31, and 64.3%for afforestation. Overall, these results indicate that SPOTHRG satellite data and support vector machines are useful for estimating aboveground carbon stock.

关键词： Aboveground carbon stock Support vector machine SPOT-HRG Darabkola

Phenology and population dynamics of sand flies in a new focus of visceral leishmaniasis in Eastern Azarbaijan Province,North western of Iran

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Asian Pacific Journal of Tropical Medicine 2011年第8期4卷 604-609页

作者： Teimour Hazratian Yavar Rassi mohammad Ali Oshaghi mohammad Reza Yaghoobi-Ershadi Esmael fallah mohammad Reza Shirzadi Sina Rafizadeh Department of Medical Entomology and Vector Control School of Public HeallhTehran University of Medical SciencesTehranIran Department of Parasitology School of MedicineMedical Science/University of TabrizIran Zoonosis Department Ministry of Health& Medical Education Violence and Injury Prevention Safety Promotion Office Emergency Management CenterMinistry of Health & Medical Education

Objective:To investigate species composition,density,accumulated degree-day and diversity of sand flies during April to October 2010 in Azarshahr district,a new focus of visceral leishmaniasis in north western ***:Sand flies were collected using sticky traps biweekly and were stored in 96%*** specimens were mounted in Puri’s medium for species identification using valid keys of *** density was calculated by the formula: number of specimens/m of sticky traps and number of specimens/ number of ***-day was calculated as follows:(Maximum temperature + Minimum temperature)/2—Minimum *** indices of the collected sand flies within different villages were estimated by the Shannon- weaver formula(H’=sum form(i=1) to s Pi log_e Pi ).Results:Totally 5 557 specimens comprising 16 Species(14 Phlebotomus,and 2 Sergentomyia) were *** activity of the species extended from April to *** sand-flies in resting places were Phlebotomus papatasi, Phlebotomus sergenti and Phlebotomus *** monthly average density was 37.***.41.1, 40.23,30.38 and 30.67 for Almalodash,Jaragil,Segaiesh,Amirdizaj and Germezgol villages, *** degree-day from early January to late May was approximately 289 degree *** minimum threshold temperature for calculating of accumulated degree-day was 17.32℃.According on the Shannon-weaver(H’),diversity of sand flies within area study were estimated as 0.917,1.867,1.339,1.673,and 1.562 in Almalodash,Jaragil,Segaiesh,Amirdizaj and Germezgol villages,***:This study is the first detailed research in terms of species composition,density,accumulated degree-day and diversity of sand flies in an endemic focus of visceral leishamaniasis in Azarshahr *** population dynamics of sand flies in Azarshahr district were greatly affected by climatic *** to this study the highest activity of the collected sand fly species occurs at the ter

关键词： Sand fly Visceral leishmaniasis Diversity Degree day Density Iran

Analytical Study on the Rate of Sound Transmission Loss in Single Row Honeycomb Sandwich Panel Using a Numerical Method

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Sound & Vibration 2020年第2期54卷 127-137页

作者： Rohollah fallah Madvari mohammad Reza Monazzam Mohsen Niknam Sharak Mohsen Mosa Farkhani Student Research Committee Department of Occupational Health EngineeringSchool of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Department of Occupational Health Engineering School of Public HealthTehran University of Medical SciencesTehranIran Department of Mechanical Engineering University of BirjandBirjandIran

Honeycomb structures have recently,replaced with conventional homogeneous *** the fact that sandwich panels containing a honeycomb core are able to adjust geometric parameters,including internal angles,they are suitable for acoustic control *** main objective of this study was to obtain a transmission loss curve in a specific honeycomb frequency range along with same overall dimensions and *** this study,a finite element model(FEM)in ABAQUS software was used to simulate honeycomb panels,evaluate resonant frequencies,and for acoustic *** model was used to obtain acoustic pressure and then to calculate the sound transmission loss(STL)in MATLAB *** and acoustic analysis of panels were performed in the frequency range of 1 to 1000 *** models analyzed in this design includes 14-single row-honeycomb designs with angles of−45°,−30°,−15°,0°,+15°,+30°,+45°.The results showed that a-single row and−45°cell angle honeycomb panel in the frequency range of 1 to 1000 Hz had the highest STL as well as the highest number of frequency modes(90 mods).Furthermore,the panel had the highest STL regarding the area under the STL curve(dB∙Hz).The panels containing more frequency mods,have a higher transmission ***,the sound transmission loss is more sensitive to the cell angle variable(θ).In other studies,the STL was more sensitive to the number of honeycomb cells in the horizontal and vertical directions,as well as the angle of cells.

关键词： Finite element model honeycomb sound transmission loss