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Introducing an effective coherence function to generate non-uniform ground motion on topographic site using time-domain boundary element method

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 89-100页

作者： Mohsen Isari reza Tarinejad Faculty of Civil Engineering University of TabrizTabrizEast Azerbaijan ProvinceIran

In this study,a comprehensive parametric analysis was performed on non-uniform excitation of V-shaped topography using the boundary element method in time *** this purpose,wave scattering analysis was carried out on a topography subjected to the SV-wave for different predominant frequencies and shape *** on the numerical results,new coherence and time delay functions are proposed to generate non-uniform ground motion for topographic *** efficiency and accuracy of the proposed functions for real engineering problems are indicated by comparison with observations reported in previous literature.

关键词： site effect time delay boundary element method amplification coherence function

Gravity-driven powder flow and the influence of external vibration on flow characteristics

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Particuology 2024年第5期88卷 201-209页

作者： Muhammad Shahid ansari Ratna Kumar Annabattula Sathyan Subbiah Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036India

The controlled and homogeneous flow of dry granular powders through hoppers is essential for applications,namely,packaging of food grains,fertilizers and additive manufacturing processes such as directed energy deposition for better product *** of the major issues encountered in the granular flows through hoppers is flow stagnation due to the well-known arching ***-assisted granular flow through hoppers is one of the mechanisms used for better mass flow *** this work,the influence of external mechanical vibration on the powder flow is investigated experimentally and using discrete element ***,the mass flow rate through the hopper increases with an increase in vibration amplitude and then decreases,signifying the existence of an optimal amplitude of *** DEM simulations explained the underlying mechanisms for the existence of an optimal amplitude of vibration corresponding to the maximum mass flow rate.A range of vibration amplitudes from 0 mm to 3.5 mm is used to study the flow behaviour;the maximum flow of around 33 g/s to 35 g/s is observed for 0.75 mm to 1.25 mm vibration amplitude for the hopper-particle combination studied in this *** work also reports the influence of vibration frequency,hopper,and particle dimension on the flow *** research facilitates the effective use of mechanical vibration to enhance powder flow that can further be extended to non-spherical and multi-material particles.

关键词： Discrete element method Flow rate Granular flow Path tracking Vibration intensity

Effect of methane content and the oscillating electric field between electrodes on atmospheric Ar/methane plasma jet and DLC coating deposition

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Plasma Science and Technology 2020年第8期22卷 76-89页

作者： reza SAFARI Farshad SOHBATZADEH Department of Atomic and Molecular Physics Faculty of Basic SciencesUniversity of MazandaranBabolsar 47416Iran

In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DLC)film deposition have been *** of RF atmospheric Ar/methane plasma jet such as active species density,length,electron temperature,appearance and ionization process of argon/methane plasma jet are changed due to the changing of methane flow content and electric field vector and its *** increasing methane flow,the formation of C2 hydrocarbon and CH band content is decreased because injected electrical energy to a mixture of Ar/methane gases is insufficient to stabilize the ionization process of methane gas and the electrical-chemical reaction rate is *** shortening the gas gap between two electrodes,electric field strength and its gradient are increased leading to more energy injection to the ***-chemical reactions are strengthened leading to increasing the CH band *** phenomena introduce the Ar/methane plasma jet in different modes causing to deposit the DLC film with different structures and *** using quartz glass and alumina ceramic as dielectric barriers tubes,RF atmospheric pressure Ar/methane plasma jet has been used to deposit DLC coating in different *** methane content and shortening the gas gap leads to decreasing sp3 bonded content and the quality of the deposited film.

关键词： RF atmospheric plasma methane flow electric field

Stochastic price based coordinated operation planning of energy storage system and conventional power plant

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1020-1032页

作者： Mohammad reza SHEIBANI Gholam reza YOUSEFI Mohammad Amin LATIFY Department of Electrical and Computer Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran

A generation company(GENCO)which has a conventional power plant(CPP)intends to add an energy storage system(ESS)beside the CPP to increase its flexibility and *** this purpose,a new model is proposed for coordinated operation planning of the CPP and ESS in energy and spinning reserve markets in the presence of a bilateral *** proposed model is based on the stochastic price based unit commitment(PBUC)and price based storage commitment(PBSC).The uncertainties of the energy and spinning reserve prices and delivery requests in the spinning reserve market are modeled via scenarios based upon historical *** proposed model maximizes the profitability of the ESS beside the CPP and encourages the GENCO to invest the *** technology options to use beside the CPP are determined by economic *** results show that utilization of ESSs improves the technical operation of CPPs,as well as GENCOs’profitability.

关键词： Energy storage system Conventional power plant Operation planning Price based unit commitment

Helicobacter pylori Bab A in adaptation for gastric colonization

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World Journal of Gastroenterology 2017年第23期23卷 4158-4169页

作者： Shamshul ansari Yoshio Yamaoka Department of Environmental and Preventive Medicine Oita University Faculty of Medicine Department of Medicine-Gastroenterology Baylor College of Medicine

Helicobacter pylori(H. pylori) as a causative agent of gastric complications, is well adapted for the colonization of gastric mucosa. Although the infectious process depends on several factors, the adhesion to the gastric mucosa is the first and important step. Among several outer membrane proteins, Bab A is one of the significant protein involving in many inflammatory processes in addition to its role in the attachment for the persistent colonization. We performed a Pub Med search using the key words: "bab A ", "pylori", "gastric complications", "homologous recombination", "slipped strand mispairing"; a total of 249 articles were displayed. Of these we mainly focused on articles with the full text in English and published between 2005 and 2016. H. pylori Bab A is involved in binding with receptors; however, its synthesis is regulated by phase variation. In this review we confirm that H. pylori bab A can be modulated at the molecular and functional levels to adapt to the stress within the gastro-intestinal tract.

关键词： BabA Gastric complications Helicobacter pylori Homologous recombination Slipped strand mispairing

Prediction of spatial land use changes based on LCM in a GIS environment for Desert Wetlands-A case study: Meighan Wetland,Iran

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International Soil and Water Conservation Research 2019年第1期7卷 64-70页

作者： Amir ansari Mohammad H.Golabi Department of Environmental Sciences Faculty of Agriculture and Natural ResourcesArak UniversityArak 38156-8-8349Iran College of Natural and Applied Sciences University of Guam MangilaoGuam 96923United States

Meighan Wetland and its surroundings have undergone many changes in recent *** study aims to monitor and predict land use changes using the land change model (LCM) module in the Meighan *** Sat images of years 2000,2007 and 2015 were used to produce digital land use *** images were classified into seven classes including;Salt lake,Agriculture,Rangeland,Manmade,Wastewater,Wetland and Mine *** LCM module in Idrisi GIS software was used to analyze the land use changes for predicting the land uses status in 2015,based on artificial neural network (ANN) and Markov Chain *** ANN was trained with various influencing factors including;distance from road,distance from manmade areas,distance from land changed edge,distance from stream,elevation and *** results indicated that 1663.88 ha of the rangeland cover and 715.68 ha of the salt lake cover have been degraded during the 2000-2015 ***,the wetland,mine,wastewater and manmade degradation are increased to 724 ha,335 ha,37 ha and 270 ha in comparison to initial land ***,the result shows that rangeland and salt lake areas will decrease in the year 2030 compare to 2015,while,wetland,mine and manmade land changes may increase.

关键词： LCM Prediction Meighan wetland Land use changes Artificial Neural Network

Quantification by allometric equations of carbon sequestered by Tectona grandis in different agroforestry systems

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Journal of Forestry Research 2013年第4期24卷 699-702页

作者： Avinash Jain S.A.ansari Tropical Forest Research Institute

Non destructive methods for quantification of carbon seques- tration in tropical trees are inadequately developed. We described a stan- dardized method for estimating carbon stock in teak （Tectona grandis Linn. F.）. We developed linear allometric equations using girth at breast height （GBH）, height and age to quantify above ground biomass （AGB）. We used AGB to estimate carbon stock for teak trees of different age groups （1.5, 3.5, 7.5, 13.5, 18.5 and 23.5 years）. The regression equation with GBH, y = 3.174x - 21.27, r2=0.898 （p 〈0.01）, was found precise and convenient due to the difficulty in determination of height and age in dense natural forests of teak. The equation was evaluated in teak agroforestry systems that included Triticum aestivum （wheat）, Cicer arietinum （gram）, Withania somnifera （ashwagandha）,

关键词： Tectona grandis agroforestry system allometric equation carbon sequestration above ground biomass

Using Ecosystem Service Modeler (ESM) for Ecological Quality, rarity and Risk Assessment of the wild goat habitat, in the Haftad-Gholleh protected area

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International Soil and Water Conservation Research 2019年第4期7卷 346-353页

作者： Amir ansari Mohammad H.Golabi Department of Environmental Sciences Faculty of Agriculture and Natural ResourcesArak UniversityArak38156-8-8349Iran College of Natural and Applied Sciences University of GuamMangilaoGuam96923USA

In recent years,the destruction of habitats has reduced the wild goat population in the Haftad-Gholleh protected *** wild goat (Capra aegagrus) is known as symbol of biodiversity of Markazi *** a field study conducted between 2007 and 2017,the number of wild goats were surveyed and threat to their habitat were determined as the population and the ecological conditions as well as their movements in the Haftad-Gholleh were *** image of year 2018 was used to produce digital land use maps for this *** Quality,Rarity and Risk Assessment was performed with ESM,HQR and HRA *** images were classified into three classes including;Agriculture-livestock,Rangeland,and Residential *** results indicated that 75% of the casualties of the wild goat by Peste des Petits Ruminants disease were from the Chekab Valley and 25% from the Sibak *** 80% of deaths among the population of wild goats were observed in the month of ***,there are two important mountainous and plains habitats in the Haftad-Gholleh *** the biggest threats and more devastating stressors in the region were to villagers,agricultural-livestock and roads ***,among the stressors,the agriculture-livestock caused more deaths in the mountainous habitat of the wild ***,there is an urgent need for habitat conservation of the existing population of the wild goat in Haftad-Gholleh area.

关键词： Haftad-gholleh Wild goat (Capra aegagrus) Wildlife disease Habitat quality and rarity Habitat risk assessment

Gardaneh Salavat porphyry copper system: Is it about metal endowment or fertility of the porphyritic intrusion?

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Acta Geochimica 2022年第3期41卷 496-514页

作者： Seyyed reza Mashhadi Department of Geoscience Aarhus UniversityHøeghGuldbergs Gade 28000 Aarhus CDenmark

Gardaneh Salavat porphyry copper system is located in the northwest of Iran. It comprises a quartz diorite to diorite porphyritic intrusion that created extensive alteration haloes in the host rocks. Despite all technical considerations, the exploration activities did not yield to ore discovery. As the matter of fact, all of the geological,geophysical, and geochemical characteristics of a porphyry Cu-Au deposit exist but there is no economic mineralization. Detailed examinations suggest that the only reasonable explanation can be related to the infertility or low metal endowment of the porphyritic intrusion. The reasons include(1) anomalous ranges of Cu, Au, and Mo rather than economic ore grades,(2) weakly development of potassic alteration,(3) probably sulfur saturation of magma that occurred before intrusion emplacement in the host rocks, and(4) probably low metal endowment in the regional scale and the lack of known porphyry copper deposits in close neighborhoods. It is tried to test the proposed hypothesis with the introduced fertility indicators based on major and trace element geochemistry. However,current fertility indicators could not prove or reject the proposed hypothesis for Gardaneh Salavat porphyritic intrusion because of the high-K calc-alkaline to shoshonitic nature of the intrusive rocks together with the unavailability of relatively fresh/unaltered samples. This case study is notable to examine because(1) it shows that characterization of fertile from barren intrusions seems to be as important as vectoring towards concealed porphyry copper deposits, especially while dealing with deep exploration targets that are associated with high financial risks, and(2) it highlights the inefficiencies and uncertainties in introduced magma fertility indicators for porphyry copper intrusions. As a result, it is of high importance to conduct an overarching investigation on other possible fertility indicators as a fundamental need for the future of the exploration

关键词： Porphyry Copper Fertility Metal endowment Barren intrusion