检索结果-南通市图书馆

Chinese Journal of Aeronautics 2021年第4期34卷 293-305页

作者： hossein moradi PARI hossein BOLANDI Department of Electrical Engineering Iran University of Science and TechnologyTehran 009821Iran

This paper addresses the challenge of synchronized multiple spacecraft attitude reorientation in presence of pointing and boundary constraints with limited inter-spacecraft communication *** attitude pointing constraint among the fleet of spacecraft has also been modeled and considered during the attitude maneuvers toward the desired *** fling control structure that consists of decentralized path planners based on virtual structure approach joint with discrete time optimal local controller is designed to achieve the mission's *** to digital computing of spacecraft's onboard computer,local optimal controller based on discrete time prediction and correction algorithm has been *** time step of local optimal algorithm execution is designed so that the spacecraft track their desired attitudes with appropriate error *** convergence of the proposed architecture and stability of local controller's tracking error within appropriate upper bound are ***,a numerical simulation of a stereo imaging scenario is presented to verify the performance of the proposed architecture and the effectiveness of the algorithm.

关键词： Decentralized Discrete time Formation flying Optimal control Spacecraft Virtual structure approach

Evaluating and modeling the spatiotemporal pattern of regional-scale salinized land expansion in highly sensitive shoreline landscape of southeastern Iran

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2018年第6期10卷 946-958页

作者： Mohammad SHAFIEZADEH hossein moradi Sima FAKHERAN Department of Natural Resources Isfahan University of Technology

Taking an area of about 2.3×10~4 km~2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and 2015 were acquired as the main source of data. Radiometric, atmospheric and cutline blending methods were used to improve the quality of images and help better classify salinized land areas under the support vector machine method. A set of landscape metrics was also employed to detect the spatial pattern of salinized land expansion from 1986 to 2015. Four factors including distance to sea, distance to sea water channels, slope, and elevation were identified as the main contributing factors to land salinization. These factors were then integrated using the multi-criteria evaluation (MCE) procedure to generate land sensitivity map to salinization and also to calibrate the cellular-automata (CA) Markov chain (CA-Markov) model for simulation of salt-affected lands up to 2030, 2040 and 2050. The results of this study showed a dramatic dispersive expansion of salinized land from 7.7 % to 12.7% of the total study area from 1986 to 2015. The majority of areas prone to salinization and the highest sensitivity of land to salinization was found to be in the southeastern parts of the region. The result of the MCE-informed CA-Markov model revealed that 20.3% of the study area is likely to be converted to salinized lands by 2050. The findings of this research provided a view of the magnitude and direction of salinized land expansion in a past-to-future time period which should be considered in future land development strategies.

关键词： soil salinization remote sensing CA-Markov salt land expansion southeastern Iran

Introducing a new rock abrasivity index using a scaled down disc cutter

在线全文

学校读者我要写书评

暂无评论

Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第3期3卷 24-37页

作者： Maziar moradi Mohammad hossein Khosravi Jafar Khademi Hamidi Department of Civil and Environmental Engineering University of StrathclydeGlasgowG11XQUK Department of Mining Engineering Faculty of EngineeringUniversity of BirjandBirjand ***Iran

Rock abrasivity influences wear of cutting tools and consequently,performance of mechanized tunneling *** methods have been proposed to evaluate rock abrasivity in recent decades,each one has its own *** this paper,a new method is introduced to estimate wear of disc cutters based on rock cutting tests using scaled down discs(i.e.54 and 72 mm diameter).The discs are made of H13 steel,which is a common steel type in producing real-scale discs,with hardness of 32 and 54 *** small-scale linear rock cutting machine and a new abrasion test apparatus,namely University of Tehran abrasivity test machine,are utilized to perform the *** width of the worn discs is monitored and presented as the function of the accumulated test run to classify the rock *** tests show that by increasing the uniaxial compressive strength(UCS)of the rock samples,wear rate is doubled gradually that reveals the sensitivity of the test procedure to the main pa-rameters affecting the abrasivity of hard *** the rocks with the highest UCS,the normal wear stops after performing 5 to 10 rounds of the tests,and then,deformation of the disc tip is *** abrasivity indices are defined based on the abrasivity tests results and their correlations with Cerchar Abrasivity Index(CAI)and UCS are *** of the established correlations in this study with previous investigations dem-onstrates the sensitivity of the indices to the parameters affecting wear of the disc cutters and repeatability of the outputs obtained from abrasivity tests using scaled down *** of this study can be used to enhance the accuracy of rock abrasivity classifications.

关键词： Mechanized tunneling Rock cutting Rock abrasivity classification University of Tehran abrasivity test Wear

Molecular dynamic simulation of carbon dioxide,methane,and nitrogen adsorption on Faujasite zeolite

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2022年第3期35卷 70-76页

作者： Hojatollah moradi Hedayat Azizpour hossein Bahmanyar Mohammad Emamian Surface Phenomenon and Liquid-Liquid Extraction Research Lab School of Chemical EngineeringCollege of EngineeringUniversity of TehranTehranIran Fouman Faculty of Engineering College of EngineeringUniversity of TehranIran

Removing impurities such as carbon dioxide and nitrogen from natural gas is a technical challenge and one of the major concerns in natural gas treatment *** this study,adsorption of CH_(4),N_(2),and CO_(2)on the Faujasite(FAU)zeolite has been studied using molecular dynamics simulation at temperatures of 293,308,and 323 K and pressures up to 1 *** force field was used to model the interactions between zeolite and guest *** and atom-based summation methods were used for the calculation of electrostatic and van der Waals forces,*** results were modeled using Langmuir,Freundlich,Toth,and Sips adsorption *** isotherm for CO_(2),and Toth isotherm for CH_(4)and N_(2)pure compounds showed the best *** of adsorption for CH_(4),CO_(2),and N_(2)were calculated to be-15.48,-24.1,and-13.31 kJ·mol^(-1),respectively.A comparative study showed that the simulation model was successful in predicting the overall trend of the adsorption with acceptable accuracy.

关键词： Adsorption Molecular simulation Isotherms Zeolite

Adsorption of Folic Acid on the Single-walled Carbon Nanotubes: AIM and NBO Analyses via DFT

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2015年第8期34卷 1161-1169页

作者： Shahla Hamedani Shahram moradi hossein Aghaie Department of Chemistry Science and Research Branch Islamic Azad University Department of Chemistry Tehran North Branch Islamic Azad University

In the present work, the behavior of folic acid （FA） molecule adsorbed onto single-walled carbon nanotube （SWCNT） was examined using the DFT-B3LYP/6-31G＊ level. In order to obtain information about the binding features of SWCNT as adsorbent with FA molecule, several studies, including the structural and electronic parameters and also the Atoms in Molecules （AIM） analysis, were performed. It was observed that the FA molecule via hydrogen bond prefers to adsorb on SWCNT with adsorption energy of about -18.70 kcal/mol. The molecular orbitals （HOMO and LUMO）, natural bond orbital （NBO）,analysis, and density of states （DOS） plot indicated that a charge about 0.032 [ e [ is transferred from the FA molecule to the nanotube. After solvation energy calculations, it was found that the presence of a polar solvent causes an increase in FA adsorption on the single-walled carbon nanotube. Topological features such as electron energy density （Hc） and Laplacian of the electron density （V2p~） demonstrate partial covalent nature for H（ll6）...O（10） interaction in the FA/SWCNT complex. According to the calculated results, the single-walled carbon nanotubes are expected to be a potential efficient adsorbent for the adsorption of folic acid drug and also can be used as a suitable drug delivery vehicle within biological systems.

关键词： adsorption, carbon nanotube, folic acid, DFT, AIM

Fe(HSO_4)_3:An efficient,heterogeneous and reusable catalyst for the synthesis of 14-aryl- or alkyl-14H-dibenzo[a,j]xanthenes

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第12期19卷 1423-1426页

作者： hossein Eshghi Mehdi Bakavoli Hassanali moradi Department of Chemistry Ferdowsi University of MashhadMashhad 91775-1436Iran

Fe（HSO4）3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.

关键词： Heterogeneous catalyst Fe(HSO4)3 Xanthenes Naphthol Aldehydes

Ferric hydrogensulfate catalyzed aerobic oxidative coupling of 2-naphthols in water or under solvent free conditions

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第6期20卷 663-667页

作者： hossein Eshghi Mehdi Bakavoli Hassanali moradi Department of Chemistry Ferdowsi University of Mashhad P.O.Box 91775-1436

The symmetric oxidative coupling reactions of 2-naphthol derivatives with both ferric hydrogensulfate in water and silica ferric hydrogensulfate in solvent free conditions were carried out. The advantages of this green procedure are inexpensive catalyst or cocatalyst, reusability of catalyst, organic solvent-free procedures and simple workup.

关键词： Silica ferric hydrogensulfate Naphthol BINOL Solvent-free

Coupling system application in photocatalytic degradation of methylorange by TiO_2, TiO_2/SiO_2 and TiO_2/SiO_2/Ag

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2015年第12期34卷 851-858页

作者： hossein Ghasemi Mobtaker Seyed Javad Ahmadi Shahram moradi Dehaghi Taher Yousefi Nuclear Fuel Cycle Research School Nuclear Science and Technology Research Institute Faculty of Chemistry Tehran North Branch Islamic Azad University

Three different photocatalysts including TiO2, TiO2/SiO2 and TiO2/SiO2/Ag were synthesized via sol–gel growth method, in which colloidal silica was used as Si source, titanium tetra iso-propoxide (TTiP) as titanium source, Ag+ as dopant ion and hydroxypropyl cellulose (HPC) as dispersant. The purpose was to study the enhancement of photocatalytic activity of TiO2 by deposition on SiO2 colloids and also doping with Ag ion. The catalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR) and Brunauer–Emmett–Teller (BET) methods. It is confirmed that the major phase in all catalysts is anatase. Photocatalytic activity was studied in various conditions for degradation of methylorange (as a model pollutant) to evaluate the effect of some parameters on degradation efficiency. Studying the degradation process in various pH values reveals that the degradation is more efficient in acidic solution than alkaline condition. Coupling the photocatalytic process with some fields called electro-photochemical (EP), magnetic-photochemical (MP) and ultrasonic-photochemical (UP) was studied at two pH values which were compared with photochemical (P) alone. It is concluded that in most cases, the EP is the best coupled system and has the maximum efficiency. Liquid chromatography–mass spectrometry (LC–MS) analysis was used to check the complete decomposition of methylorange at the end of process.

关键词： Doping Electro-photochemical Magnetic-photochemical Ultrasonic-photochemical Sol–gel

A data-mining approach to biomarker identification from protein profiles using discrete stationary wavelet transform

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第11期9卷 863-870页

作者： Hussain MONTAZERY-KORDY Mohammad hossein MIRAN-BAYGI Mohammad Hassan moradi Department of Electrical and Computer Engineering Tarbiat Modares University Faculty of Biomedical Engineering Amir Kabir University of Technology

Objective: To develop a new bioinformatic tool based on a data-mining approach for extraction of the most infor- mative proteins that could be used to find the potential biomarkers for the detection of cancer. Methods: Two independent datasets from serum samples of 253 ovarian cancer and 167 breast cancer patients were used. The samples were examined by surface- enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS). The datasets were used to extract the informative proteins using a data-mining method in the discrete stationary wavelet transform domain. As a dimensionality re- duction procedure, the hard thresholding method was applied to reduce the number of wavelet coefficients. Also, a distance measure was used to select the most discriminative coefficients. To find the potential biomarkers using the selected wavelet coefficients, we applied the inverse discrete stationary wavelet transform combined with a two-sided t-test. Results: From the ovarian cancer dataset, a set of five proteins were detected as potential biomarkers that could be used to identify the cancer patients from the healthy cases with accuracy, sensitivity, and specificity of 100%. Also, from the breast cancer dataset, a set of eight proteins were found as the potential biomarkers that could separate the healthy cases from the cancer patients with accuracy of 98.26%, sensitivity of 100%, and specificity of 95.6%. Conclusion: The results have shown that the new bioinformatic tool can be used in combination with the high-throughput proteomic data such as SELDI-TOF MS to find the potential biomarkers with high discriminative power.

关键词： Proteomics Discrete stationary wavelet transform Data mining Feature selection Biomarker Cancer classification

Infestation and pathological lesions of some lymph nodes induced by Linguatula serrata nymphs in sheep slaughtered in Shahrekord Area(Southwest Iran)

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2015年第7期5卷 566-570页

作者： Hamidreza Azizi hossein Nourani Abdollah moradi Department of Pathobiology School of Veterinary Medicine Shahrekord University School of Veterinary Medicine Shahrekord University

Objective: To determine the infection rates of mesenteric and mediastinal lymph nodes in relation to Linguatula serrata(L. serrata) nymphs. Methods: In the present study, mesenteric and mediastinal lymph nodes of 200 sheep with different sex and age that were slaughtered in a Shahrekord slaughterhouse were collected. The lymph nodes were examined macroscopically and for histopathological examination, tissue samples were taken from the gross lesions processed routinely by paraffin method and stained with hematoxylin and eosin. Results: Out of 200 examined sheep, the mesenteric lymph nodes in 18 sheep(9%) and the mediastinal lymph nodes of 9 sheep(4.5%) were infected by L. serrata nymphs. The infection rate increased with age, but no significant difference was observed between males and females or the two types of lymph nodes(P > 0.01). Different nonspecific gross and macroscopic lesions were seen in infected lymph nodes. L. serrata nymph sections were observed in some histopathological slides. Conclusions: It is concluded that the sheep may play an important role in linguatulosis of final hosts and human beings in this region.

关键词： Linguatula serrata Lymph nodes Histopathological examination Pathology Sheep