检索结果-南通市图书馆

Journal of Magnesium and Alloys 2023年第8期11卷 2750-2762页

作者： Martin Wolff mohammad marvi-mashhadi Eshwara Nidadavolu Henrik Lüneburg Thomas Ebel Regine Willumeit-Römer Institute of Metallic Biomaterials at Helmholtz-Zentrum Hereon Max-Planck Str.1D-21502 GeesthachtGermany Institute of Material Systems Modeling Helmholtz-Zentrum HereonMax–Planck-Str.121502 GeesthachtGermany

In this study,a binder based 3D-printing technology *** Granular Fabrication(FGF)technique was used to produce interconnected and open porous Mg-6.3Gd bone scaffolds for compression test *** consolidation of the green parts(as printed scaffolds)was performed using solvent debinding in cyclohexane and subsequent conventional sintering in argon *** tests were performed on as sintered ***,a simulation strategy was developed for modeling the compression behavior of the sintered parts,utilizing the data from the experimental *** experimental compression test results and the simulation strategy for the compression behavior of the 3D-printed scaffolds demonstrated good agreement.

关键词： Magnesium Mg-6.3Gd Additive manufacturing Simulation FGF Biodegradable

A probabilistic model for assessing the reliability of wind farms in a power system

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第6期14卷 464-474页

作者： Mostafa HOSSEINPOUR Habib RAJABI mashhadi mohammad Ebrahim HAJIABAD Faculty of Engineering Department of Electrical EngineeringFerdowsi University of MashhadMashhadIran Center of Excellence on Soft Computing and Intelligent Information Processing Ferdowsi University of MashhadMashhadIran

Modeling the generation of a wind farm and its effect on power system reliability is a challenging task,largely due to the random behavior of the output *** this paper,we propose a new probabilistic model for assessing the reliability of wind farms in a power system at hierarchical level II(HLII),using a Monte Carlo *** proposed model shows the effect of correlation between wind and load on reliability *** can also be used for identifying the priority of various points of the network for installing new wind farms,to promote the reliability of the whole system.A simple grid at hierarchical level I(HLI) and a network in the north-eastern region of Iran are *** results showed that the correlation between wind and load significantly affects the reliability.

关键词： Wind farm Reliability Priority Probabilistic model

Texture evolution and mechanical anisotropy of an ultrafine/nano-grained pure copper tube processed via hydrostatic tube cyclic expansion extrusion

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2241-2251页

作者： Seyed Moien Faregh Ghader Faraji Mahmoud Mosavi mashhadi mohammad Eftekhari School of Mechanical Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Texture evolution and mechanical anisotropic behavior of an ultrafine-grained(UFG)pure copper tube processed by recently introduced method of hydrostatic tube cyclic expansion extrusion(HTCEE)was *** the UFG tube,different deformation behavior and a significant anisotropy in tensile properties were recorded along the longitudinal and peripheral *** HTCEE process increased the yield strength and the ultimate strength in the axial direction by 3.6 and 1.67 times,***,this process increased the yield strength and the ultimate strength in the peripheral direction by 1.15 and 1.12 times,*** ratio of ultimate tensile strength in the peripheral direction to that in the axial direction,as a criterion for mechanical anisotropy,are 1.7 and 1.16 for the as-annealed coarse-grained and the HTCEE processed UFG tube,*** results are indicative of a reducing effect of the HTCEE process on the mechanical ***,after HTCEE process,a low loss of ductility was observed in both directions,which is another advantage of HTCEE *** measurements revealed a slight increment of hardness values in the peripheral direction,which is in agreement with the trend of tensile *** analysis was conducted in order to determine the oriental distribution of the *** obtained{111}pole figures demonstrate the texture evolution and reaffirm the anisotropy observed in mechanical *** electron microscopy micrographs showed that different modes of fracture occurred after tensile testing in the two orthogonal directions.

关键词： severe plastic deformation ultrafine grained hydrostatic tube cyclic expansion extrusion anisotropy texture

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

在线全文

学校读者我要写书评

暂无评论

国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

The effect of time and type of stress moderators on yield and yield components of cotton on conventional and double‑cropping systems under saline conditions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Cotton Research 2021年第4期4卷 322-336页

作者： BORZOUYI Zeinab ARMIN mohammad marvi Hamid Department of Agronomy and Plant Breeding Sabzevar BranchIslamic Azad UniversitySabzevarIran

Background:Today,stress moderators are employed to mitigate crop loss due to the adverse effects of environmental *** current research aimed to investigate the impacts of time and stress moderator types on agro-physiological responses of cotton on conventional and double-cropping systems during 2017 and 2018 under saline conditions.A split-plot factorial experiment was carried out in a randomized complete block design with three *** system[conventional(recommended planting date)and double-cropping systems(sowing after harvest of wheat)]were considered as the main plots,and stress moderator type at four levels[water control,2 mmol·L^(-1) Salicylic acid(SA),100 mmol·L^(-1) Glycine betaine(GB),and 100μmol·L^(-1) sodium nitroprusside(SNP)]and application time(flowering and flowering+bolling stages)were regarded as ***:Plant height,reproductive branch number,the number of bolls,10-boll weight,1000-seed weight,biological yield,seed cotton yield,lint yield,chlorophyll a,chlorophyll b,carotenoids,total chlorophyll,sodium,potassium,and proline content were less in double-cropping system comparing with conventional *** with the stress moderators alleviated soil salinity effects on yield,yield components,and biochemical traits of *** spraying led to maximum plant height,branch number,the number of bolls per plant,10-boll weight and seed cotton *** spraying yielded the highest 1000-seed weight,biological yield,lint percentage and lint *** highest chlorophyll a,chlorophyll b,carotenoids,and total chlorophyll content resulted from SNP ***,yield components,and biochemical traits did not respond to the stress moderator types in double-cropping ***,the highest chlorophyll a,carotenoids,proline content,the number of bolls per plant,and seed cotton yield resulted from SNP spraying in conventional *** statistically significant differences were observed between spraying with SNP and SA in

关键词： Cotton Glycine betaine Salicylic acid Salinity Sodium nitroprusside Sowing date

Determining structural variation in a managed mixed stand in an old-growth forest, northern Iran

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2019年第5期30卷 1859-1871页

作者： Mohsen Javanmiri Pour mohammad Reza marvi Mohadjer Vahid Etemad Meghdad Jourgholami Department of Forestry Faculty of Natural ResourcesUniversity of Tehran

Numerous approaches have been developed to quantify forest structure modules.A variety has measured each as part of stand *** study was carried out in managed mixed stands in northern *** objective was to quantify stand structure and its variation before and after tree marking through the Gini index and structural triangle method.A full sampling inventory was taken in 2004 and 2014 at the beginning and end of a period,before and after tree marking operations in five *** results indicate that the Gini index was 39.5,62.2,43.0,82.0 and 74.0%forⅠ,Ⅱ,Ⅲ,ⅣandⅤstands ***,approximate structural diameters were determined as a large category forⅠ,Ⅱ,ⅢandⅤstands while standⅡhad an intermediate-large class pre-tree marking to an intermediate-small class post-tree *** paired t-test results were not significant for tree numbers and growing stock changes for all species,and for beech,hornbeam,and velvet maple before and after tree harvesting in the whole ***,the Gini index and the structural triangle method can be used for natural stand modeling,structural diversity designation,and for management practices in nature-oriented forestry strategies.

关键词： Gini index Growing stock Mixed stand Structure changes Structural triangle method

Barrier-Certified Learning-Enabled Safe Control Design for Systems Operating in Uncertain Environments

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 437-449页

作者： Zahra marvi Bahare Kiumarsi IEEE Department of Electrical and Computer Engineering Michigan State UniversityMI 48824 USA

This paper presents learning-enabled barriercertified safe controllers for systems that operate in a shared environment for which multiple systems with uncertain dynamics and behaviors *** is,safety constraints are imposed by not only the ego system’s own physical limitations but also other systems operating *** the model of the external agent is required to impose control barrier functions(CBFs)as safety constraints,a safety-aware loss function is defined and minimized to learn the uncertain and unknown behavior of external *** specifically,the loss function is defined based on barrier function error,instead of the system model error,and is minimized for both current samples as well as past samples stored in the memory to assure a fast and generalizable learning algorithm for approximating the safe *** proposed model learning and CBF are then integrated together to form a learning-enabled zeroing CBF(L-ZCBF),which employs the approximated trajectory information of the external agents provided by the learned model but shrinks the safety boundary in case of an imminent safety violation using instantaneous sensory *** is shown that the proposed L-ZCBF assures the safety guarantees during learning and even in the face of inaccurate or simplified approximation of external agents,which is crucial in safety-critical applications in highly interactive *** efficacy of the proposed method is examined in a simulation of safe maneuver control of a vehicle in an urban area.

关键词： Control barrier functions(CBFs) experience replay learning safety-critical systems uncertainty

Burial and thermal maturity modeling of the Middle Cretaceous-Early Miocene petroleum system,Iranian sector of the Persian Gulf

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2015年第3期12卷 367-390页

作者： Zahra Sadat mashhadi Ahmad Reza Rabbani mohammad Reza Kamali Maryam Mirshahani Ahmad Khajehzadeh Petroleum Engineering Department Amirkabir University of Technology Research Institute of Petroleum Industry (RIPI)

The Cretaceous Kazhdumi and Gurpi forma- tions, Ahmadi Member of the Sarvak Formation, and Paleogene Pabdeh Formation are important source rock candidates of the Middle Cretaceous-Early Miocene pet- roleum system in the Persian Gulf. This study characterizes generation potential, type of organic matter, and thermal maturity of 262 cutting samples （marls and argillaceous limestones） from these rock units taken from 16 fields in the Iranian sector of the Persian Gulf. In addition, the burial and thermal histories of these source rocks were analyzed by one-dimensional basin modeling. Based on the total organic carbon and genetic potential values, fair hydro- carbon generation potential is suggested for the studied samples. Based on Tma~ and vitrinite reflectance values, the studied samples are thermally immature to mature for hydrocarbon generation. The generated models indicate that studied source rocks are immature in central wells. The Gurpi and Pabdeh formations are immature and the Ahmadi Member and Kazhdumi Formation are early mature in the western wells. The Pabdeh Formation is within the main oil window and other source rocks are at the late oil window in the eastern wells. The hydrocarbon expulsion from the source rocks began after deposition of related caprocks which ensures entrapment and preserva- tion of migrated hydrocarbon.

关键词： Persian Gulf. Kazhdumi Formation AhmadiMember Gurpi Formation Pabdeh Formation - MiddleCretaceous-Early Miocene petroleum system

Modeling functional brain connections in methamphetamine and opioid abusers

在线全文

学校读者我要写书评

暂无评论

Medicine in Novel Technology and Devices 2024年第1期21卷 88-96页

作者： Nasimeh marvi Javad Haddadnia mohammad Reza Fayyazi Bordbar Hakim Sabzevari University SabzevarIran Psychiatry and Behavioral Sciences Research Center Mashhad University of Medical SciencesMashhadIran

Substance abuse has become a significant problem *** primary purpose of this study was to model the functional brain connectivity in methamphetamines(Meth)and opioids(Op)groups in comparison with the healthy control(HC)*** data were recorded in Meth(n=8),Op(n=12),and HC groups(n=12)in a closed-eye resting *** NeuCube model based on a spiking neural network was used for EEG data's functional brain connectivity *** NeuCube model was evaluated quantitatively and qualitatively with model descriptive *** results showed the average value of the neuron's activation level,spikes emitted from neurons,and clustering coefficient as a communication parameter in the HC group decreased from 1154,1103,0.026 to 1036,981,0.020 in the Op group and to 511,468,0.009 in the Meth group,*** changes in indices were significant according to the ANOVA test with p〈*** decrease in indices was more significant in the Meth group than in the Op *** research findings showed that the abuse of Meth and Op causes damage to the brain's functional *** damage included shortening and limiting communication routes and decreased neurons'ability to generate membrane potential and emit inhibitory and excitatory *** were reported to be more severe in the Meth group than in the Op group.

关键词： Electroencephalogram Methamphetamines NeuCube model Opioids Spiking neural networks

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

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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