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Journal of Sustainable Business and Economics 2024年第2期7卷 69-75页

作者： Zhang Hui alireza mohammadi Faculty Of Creative Industries City University MalaysiaMalaysia City Graduate School City University MalaysiaMalaysia

This paper examines how the adoption of cloud computing affects the relationship between the technical and environmental capabilities of small and medium-sized enterprises(SMEs)in the tourism industry in Henan Province,China,thereby promoting the stable and sustainable development of the tourism industry,combining the laws of tourism market development,vigorously constructing a smart tourism project,guiding tourism cloud service providers to strengthen the cooperation and contact with the market’s tourism enterprises,introducing and utilizing cloud computing technology,optimizing and improving the functions of various tourism services of the enterprises,and enhancing the processing and analysis of enterprise-related data to provide tourism *** the processing and analysis of enterprise-related data to provide tourism information,and further study the adoption of cloud computing and its impact on small and medium-sized enterprises(SMEs)in terms of technology and business environment knowledge,so as to make the best enterprise management decisions and realize the overall enhancement of the enterprise’s tourism brand value.

关键词： SMEs Cloud Computing Technology Adoption Performance Henan Hotels

Numerical and experimental study of twin-fluid two-phase internal-mixing atomizer to develop maximum entropy method

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Chinese Journal of Aeronautics 2020年第9期33卷 2281-2294页

作者： alireza mohammadi Fathollah OMMI Department of Mechanical Engineering.Tarbiat Modares University Tehran 14115-111Iran

This paper presents an analytical, numerical, and experimental study on atomization characteristics and droplet distribution of a twin-fluid two-phase internal mixing atomizer to develop a Maximum Entropy Method(MEM). A two-phase Eulerian-Lagrangian method is utilized for atomization modeling of the inside and outside atomizer. In order to modify energy and momentum sources in the MEM, parametric studies are performed, and experimental tests are carried out to verify the results by applying the shadowgraph method. An advanced test stand is developed to prepare a wide range of changes in atomization characteristics and mixing ratios. A high degree of consistency is found between numerical results from the developed MEM and experimental tests with different gas-phase pressures and liquid flow rates. The droplet diameter and velocity distribution are reviewed based on various Weber numbers, sources of energy, and momentum. Turbulence modeling assists to estimate the breakup length and time scale precisely in the developed MEM, and distribution ranges with mean values are achieved. With reference to a strong correlation between upstream turbulence flow and the developed MEM verified by experimental tests, an ideal droplet size and velocity distribution prediction is observed.

关键词： Atomization Droplet distribution Internal-mixing atomizer Maximum entropy method Shadowgraph technique Test stand

Measuring COVID-19 vaccination coverage: an enhanced age-adjusted two-step foating catchment area model

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Infectious Diseases of Poverty 2021年第5期10卷 84-84页

作者： alireza mohammadi Abolfazl Mollalo Robert Bergquist Behzad Kiani 不详 Department of Medical Informatics School of MedicineMashhad University of Medical SciencesMashhadIran

Background:There are only limited studies on access to COVID-19 vaccines and identifying the most appropriate health centres for performing vaccination in metropolitan *** study aimed to measure potential spatial access to COVID-19 vaccination centres in Mashhad,the second-most populous city in ***:The 2021 age structure of the urban census tracts was integrated into the enhanced two-step foating catchment area model to improve *** model was developed based on three diferent access scenarios:only public hospitals,only public healthcare centres and both(either hospitals or healthcare centres)as potential vaccination *** weighted decision-matrix and analytic hierarchy process,based on four criteria(*** area,accessibility index,capacity of vaccination centres and distance to main roads),were used to choose potential vaccination centres looking for the highest suitability for *** Moran’s index(GMI)was used to measure the spatial autocorrelation of the accessibility index in diferent scenarios and the proposed ***:There were 26 public hospitals and 271 public healthcare centres in the study *** the exclusive use of public healthcare centres for vaccination can provide the highest accessibility in the eastern and north-eastern parts of the study area,our fndings indicate that including both public hospitals and public healthcare centres provide high accessibility to vaccination in central urban ***,a combination of public hospitals and public healthcare centres is recommended for efcient vaccination *** value of GMI for the proposed model(accessibility to selected vaccination centres)was calculated as 0.53(Z=162.42,P<0.01).Both GMI and Z-score values decreased in the proposed model,suggesting an enhancement in accessibility to COVID-19 vaccination ***:The periphery and poor areas of the city had the least access to COVID-19 vaccination *** spatia

关键词： COVID-19 Spatial accessibility Spatial inequality Two-step foating catchment area Vaccination coverage Iran

A UNIFYING FRAMEWORK FOR ANALYSIS AND DESIGN OF EXTREMUM SEEKING CONTROLLERS

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A UNIFYING FRAMEWORK FOR ANALYSIS AND DESIGN OF EXTREMUM SEE...

High-risk spatiotemporal patterns of cutaneous leishmaniasis:a nationwide study in Iran from 2011 to 2020

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作者： Dragan Nei Chris Manzie alireza mohammadi Will Moase the Department of Electrical and Electronic Engineering The University of Melbourne Parkville 3010 Victoria Australia the Department of Mechanical Engineering The University of Melbourne Parkville 3010 Victoria Australia

We summarize a unifying design approach to continuous-time extremum seeking that was recently reported by the authors. This approach is based on a feedback control paradigm that was to the best of our knowledge explicitly summarized for the first time in this form in our recent work. This paradigm covers some existing extremum seeking schemes, provides a direct link to off-line optimization and can be used as a unifying framework for design of novel extremum seeking schemes. Moreover, we show that other extremum seeking problem formulations can be interpreted using this unifying viewpoint. We believe that this unifying view will be invaluable to systematically design and analyze extremum seeking controllers in various settings.

关键词： Optimization extremum seeking convergence stability adaptive control.

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Infectious Diseases of Poverty 2023年第3期12卷 93-93页

作者： Neda Firouraghi Robert Bergquist Munazza Fatima alireza mohammadi Davidson H.Hamer Mohammad Reza Shirzadi Behzad Kiani Department of Medical Informatics School of MedicineMashhad University of Medical SciencesMashhadIran Ingerod BrastadSweden Formerly with the UNICEF/UNDP/World Bank/WHO Special Program for Research and Training in Tropical Diseases World Health OrganizationGenevaSwitzerland Department of Geography The Islamia University of BahawalpurBahawalpurPunjabPakistan Department of Geography and Urban Planning Faculty of Social SciencesUniversity of Mohaghegh ArdabiliArdabilIran Department of Global Health Boston University School of Public HealthBostonMAUSA Section of Infectious Diseases Department of MedicineBoston University School of MedicineBostonMAUSA Center for Disease Control and Prevention(CDC) Iran Ministry of Health&Medical EducationTehranIran Centre de Recherche en SantéPublique Universitéde Montréal7101Avenue du ParcMontréalCanada

Background Cutaneous leishmaniasis(CL)is a wide-reaching infection of major public health *** is one of the six most endemic countries in the *** study aims to provide a spatiotemporal visualization of CL cases in Iran at the county level from 2011 to 2020,detecting high-risk zones,while also noting the movement of high-risk *** On the basis of clinical observations and parasitological tests,data of 154,378 diagnosed patients were obtained from the Iran Ministry of Health and Medical *** spatial scan statistics,we investigated the disease’s purely temporal,purely spatial,spatial variation in temporal trends and spatiotemporal *** P=0.05 level,the null hypothesis was rejected in every *** In general,the number of new CL cases decreased over the course of the 9-year research *** 2011 to 2020,a regular seasonal pattern,with peaks in the fall and troughs in the spring,was *** period of September–February of 2014–2015 was found to hold the highest risk in terms of CL incidence rate in the whole country[relative risk(RR)=2.24,P<0.001)].In terms of location,six signifcant high-risk CL clusters covering 40.6%of the total area of the country were observed,with the RR ranging from 1.87 to *** addition,spatial variation in the temporal trend analysis found 11 clusters as potential high-risk areas that highlighted certain regions with an increasing ***,fve space-time clusters were *** geographical displacement and spread of the disease followed a moving pattern over the 9-year study period afecting many regions of the *** Our study has revealed signifcant regional,temporal,and spatiotemporal patterns of CL distribution in *** the years,there have been multiple shifts in spatiotemporal clusters,encompassing many diferent parts of the country from 2011 to *** results reveal the formation of clusters across counties that cover certain parts of provinces

关键词： Cutaneous leishmaniasis Spatial epidemiology Geographical Information Systems Spatiotemporal analysis SaTScan Spatial scan statistics Neglected tropical diseases Spatiotemporal clustering Iran

Design, synthesis, and nanoengineered modification of spherical graphene surface by layered double hydroxide (LDH) for removal of As (Ⅲ) from aqueous solutions

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Chinese Journal of Chemical Engineering 2023年第1期53卷 374-380页

作者： Najma Kamali Jahan B.Ghasemi Ghodsi mohammadi Ziarani Sahar Moradian alireza Badiei School of Chemistry College of ScienceUniversity of TehranTehranIran Department of Organic Chemistry Faculty of ChemistryAlzahra UniversityVanak SquareTehranIran

In this study, new nano spherical graphene modified with LDH(Layered Double Hydroxide) was prepared and used to remove As(Ⅲ) ion from aqueous solutions. At first, graphene oxide was synthesized from graphite using a well-known Hammer method. The obtained graphene oxide solution was sprayed in octanol solution under different temperatures and sprayed speed as influenced variables. The structure and physical characterization of synthesized spherical graphene oxide were determined by various techniques,including FT-IR, N_(2) adsorption–desorption, SEM, TEM, and EDX. In the next step, the hydrothermal method was applied to deposition LDH on the spherical graphene oxide. The synthesized spherical graphene modified by LDH was used to remove As(Ⅲ) as a toxic heavy metal ion. The effect of influenced variables including p H, contact time, amount of sorbent, and type eluent studied and the optimum values were as 8, 30, 50, and HCl(0.5 mol·L^(-1)), respectively. After optimization, the studied sorbent was shown a high adsorption capacity(149.3 mg·g^(-1)). The adsorption mechanism and kinetic models exhibited good agreement with the Langmuir isotherm and pseudo-second-order trends, respectively. Besides, the synthesized product was tested for seven times without significant loss in its sorption efficiency.

关键词： Graphene-based spherical adsorbent Layered double hydroxide(LDH) Adsorption Spray-assisted deep-frying

Aminobenzenesulfonamide functionalized SBA-15 nanoporous molecular sieve: A new and promising adsorbent for preconcentration of lead and copper ions

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Journal of Environmental Sciences 2012年第7期24卷 1347-1354页

作者： Leila Hajiaghababaei Babak Ghasemi alireza Badiei Hassan Goldooz Mohammad Reza Ganjali Ghodsi mohammadi Ziarani Department of Chemistry Islamic Azad UniversityShahre Rey Branch School of Chemistry College of ScienceUniversity of Tehran Center of Excellence in Electrochemistry Faculty of ChemistryUniversity of Tehran Department of Chemistry Alzahra University

A rapid method for the extraction and monitoring of nanogram level of Pbz＋ and Cuz＋ ions using uniform silanized mesopor （SBA-15） functionalized with aminobenzenesulfonamide groups and flame atomic absorption spectrometry （FAAS） is presented. Aminobenzenesulfonamide functionalized SBA-15 was synthesized according to procedure in the literature and the presence of organic groups in the silica framework was demonstrated by FT-IR spectra. The functionalized product showed the BET surface area 110 mZ/g and pore diameter 5. l nm, based on adsorption-desorption of N2 at 77 K. The effect of several variables such as （amount of adsorbent, stirring time, pH and presence of other ions in the medium） has been studied. Lead and copper were completely extracted at pH greater than 3 after stirring for 10 min. The maximum capacity of the adsorbent was found to be 191.3 ＋ 1.4 and 155.0 ＋ 1.0 ~xg of lead and copper ions/mg functionalized SBA-15, respectively. The preconcentration factor of the method was found to be 200. The detection limit of the technique was 3.4 and 0.4 ng/mL for Pb2＋ and Cuz＋, respectively. The applications of this methodology for real samples were examined by various water type, black tea and pepper samples.

关键词： aminobenzenesulfonamide functionalized SBA-15 preconcentration Pb2+ and Cu2+ions

Refractive surgery: the most cost-saving technique in refractive errors correction

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International Journal of Ophthalmology(English edition) 2018年第6期11卷 1013-1019页

作者： Seyed-Farzad mohammadi Cyrus Alinia Maryam Tavakkoli alireza Lashay Hormoz Chams Eye Research Center Farabi Eye Hospital Tehran University of Medical Sciences Department of Public Health School of Public Health Urmia University of Medical Sciences Hormoz Chams Research Chair in Public Health Ophthalmology Farabi Eye Center of Excellence Tehran University of Medical Sciences Department of Health Management and Economics School of Public Health Tehran University of Medical Sciences

AIM： To compare the lifetime and annual economic burden of spectacles, contact lenses, and refractive surgery in correction of refractive ***： This is a cross-sectional study with convenience sampling which 120 patients were interviewed in a tertiary referral hospital in the Iranian health care system. The bottom-up based cost of illness approach was estimated using a face-to-face interview to assess the direct and indirect cost of different refractive errors correction of any correction technologies. RESULTS： Correction with spectacle imposes a total direct cost of US dollar （US$） 342.5 （±8.41） per year and US$9373.5 （±230.1） per lifetime to each patient. These figures for the contact lenses were obtained US$198.3 （±0.12） and US$5203.1 （±256.3） and for refractive surgery were obtained US$19.1 （±1.2） and US$568.1 （±64.6）, respectively. Overall, based on age-adjusted prevalence rates, astigmatism had the highest share of refractive errors economic burden with a lifetime direct cost of slightly less than US$5.49 billion, while hyperopia and myopia imposed less than US$5.24 and 4.2 billion on patients, respectively. The annually imposed cost on each individual Iranian patient with refractive errors is US$308.5. CONCLUSION： Based on 18mo post refractive surgery course observation, which is generalized to whole life, refractive surgery significantly imposed much less cost compared with spectacles and contact lenses. Refractive errors among Iranians result in considerable economic burden. Using the refractive surgery instead of other two correction methods has the ability to reduce this economic loss in the future.

关键词： refractive error economic burden refractive surgery spectacle contact lenses

Wavelet-based iterative data enhancement for implementation in purification of modal frequency for extremely noisy ambient vibration tests in Shiraz-Iran

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Frontiers of Structural and Civil Engineering 2020年第2期14卷 446-472页

作者： Hassan YOUSEFI alireza TAGHAVI KANI Iradj MAHMOUDZADEH KANI Soheil mohammadiA High Performance Computing Lab Schoo of Civil EngineeringFaculy of EngineeringUniversity of TehranTehranIran School of Civil Engineering Faculty of EngineeringUniversity of TehranTehranIran

The main purpose of the present study is to enhance high-level noisy data by a wavelet-based iterative filtering algorithm for identification of natural frequencies during ambient wind vibrational tests on a petrochemical process *** of denoising methods fail to filter such noise *** the signal-to-noise ratio and the peak signal-to-noise ratio are ***-based one-step and variational-based filtering methods fail to denoise properly with thresholds obtained by theoretical or empirical *** to the fact that it is impossible to completely denoise such high-level noisy data,the enhancing approach is used to improve the data quality,which is the main novelty from the application point of view *** this iterative method,a simple computational approach is proposed to estimate the dynamic threshold ***,different thresholds can be obtained for different recorded signals in one ambient *** is in contrast to commonly used approaches recommending one global threshold estimated mainly by an empirical *** the enhancements,modal frequencies are directly detected by the cross wavelet transform(XWT),the spectral power density and autocorrelation of wavelet *** frequencies are then compared with those of an undamaged-model,simulated by the finite element method.

关键词： ambient vibration test high level noise iterative signal enhancement wavelet cross and autocorrelation of wavelets

Highly selective production of phenol from benzene over mesoporous silica-supported chromium catalyst:Role of response surface methodology in optimization of operating variables

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Chinese Journal of Catalysis 2015年第11期36卷 2020-2029页

作者： Milad Jourshabani alireza Badiei Negar Lashgari Ghodsi mohammadi Ziarani 德黑兰大学理学院化学学院德黑兰大学纳米科学和纳米技术研究中心纳米生物医药杰出研究中心 Alzahra大学理学院化学系

A Cr/SBA-16 catalyst was prepared using Cr（NO3）3 as a precursor and mesoporous silica SBA-16 as a support via a simple impregnation method. The catalyst was characterized using wide-angle X-ray diffraction （XRD）, low-angle XRD, N2 adsorption-desorption, transmission electron microscopy, and ultraviolet-visible spectroscopy. The catalyst activity was investigated in the direct bydroxylation of benzene to phenol using H2O2 as the oxidant. Various operating variables, namely reaction temperature, reaction time, amount of H2O2, and catalyst dosage, were optimized using central composite design combined with response surface methodology （RSM）. The results showed that the correla- tion between the independent parameters and phenol yield was represented by a second-order polynomial model. The high correlation coefficient （R2）, i.e., 0.985, showed that the data predicted using RSM were in good agreement with the experimental results. The optimization results also showed that high selectivity for phenol was achieved at the optimized values of the operating variables： reaction temperature 324 K, reaction time 8 h, H2O2 content 3.28 mL, and catalyst dosage 0.09 g. This study showed that RSM was a reliable method for optimizing process variables for benzene hydroxylation to phenol.

关键词： Mesoporous silica Chromium/SBA-16 catalyst Benzene hydroxylation Phenol Response surface methodology