检索结果-南通市图书馆

China Ocean Engineering 2017年第3期31卷 378-388页

作者： Ali aminfar Alireza MOJTAHEDI Hamid AHMADI mohammad hossain aminfar Civil Engineering Department Islamic Azad UniversityTabriz Branch Faculty of Civil Engineering University of Tabriz

Among numerous offshore structures used in oil extraction, jacket platforms are still the most favorable ones in shallow waters. In such structures, log piles are used to pin the substructure of the platform to the seabed. The pile＇s geometrical and geotechnical properties are considered as the main parameters in designing these structures. In this study, ANSYS was used as the FE modeling software to study the geometrical and geotechnical properties of the offshore piles and their effects on supporting jacket platforms. For this purpose, the FE analysis has been done to provide the preliminary data for the fuzzy-logic post-process. The resulting data were implemented to create Fuzzy Inference System （FIS） classifications. The resultant data of the sensitivity analysis suggested that the orientation degree is the main factor in the pile＇s geometrical behavior because piles which had the optimal operational degree of about 5° arc more sustained. Finally, the results showed that the related fuzzified data supported the FE model and provided an insight for extended offshore pile designs.

关键词： pile soil FEM offshore jacket platform pile-soil interaction, ^-logic fuzzification

Normal faulting and its role in the drainage divide migration in the Karιncalιdag region,Menderes Massif,Western Türkiye

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2025年第1期22卷 312-323页

作者： TOPAL Savaş IRFAN mohammad Pamukkale University Department of Geological EngineeringKınıklıCampusDenizli 20160Türkiye University of Kashmir Department of Earth SciencesSrinagar 190006India

Drainage divide migration refers to the shifting boundaries between adjacent drainage basins over time,driven by processes such as tectonic uplift,differential erosion,stream capture,and lithological *** phenomenon has a significant impact on water flow patterns and basin extents,serving as an indicator of the landscape's response to active tectonic *** of the key drivers of divide migration is asymmetric uplift,which causes divides to shift from areas of lower uplift to regions experiencing higher *** divides are inherently dynamic,evolving over time as drainage networks develop and adjust to changing *** study focuses on the migration of the main drainage divide along Karιncalιda?,located between Bozdo?an and *** employs geomorphic analyses using metrics such as the normalized steepness index(ksn),Chi(χ),and Gilbert *** main divide is categorized into four segments(D1–D4),with the Karacasu Fault,situated along the mountain's north-eastern boundary,identified as the primary factor influencing divide *** factors include the relatively low elevation of Karιncalιda?,uniform lithology,and consistent rainfall patterns across the *** results indicate that the main divide is currently stable,suggesting a balance between uplift and ***,higherχvalues in the D4 segment suggest that future erosion may dominate,potentially causing the divide to migrate toward the Bozdo?an *** findings highlight the dynamic nature of drainage divides and the complex interplay of tectonic,erosional,and lithological processes that shape their *** monitoring and advanced geomorphic analysis are essential for understanding the long-term stability of the divide and its response to future tectonic activity and erosional modifications.

关键词： Drainage divide migration Gilbert metrics Karıncalıdağ Karacasu Fault

Geochemical analysis of organic matter associated with gold in ore deposits:A study of Kazakhstan and Hungary

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2025年第1期44卷 23-35页

作者： Medet Junussov Asif mohammad Sotirios Longinos School of Mining and Geosciences Nazarbayev University010000AstanaKazakhstan

This study comprises the relationship between organic matter(OM)and gold occurrence using two distinctive ore deposits of the Bakyrchik gold-sulfide deposit(Kazakhstan)and Western Mecsek uranium ore deposit(Hungary).The two ore deposits are identified as organicrich sedimentary formations linked to the Variscan gold cycle *** OM is essential because it can act as a carrier for gold,influencing its distribution and behavior within the *** the nature and distribution of OM can provide insights into the processes of gold deposition and help optimize exploration and extraction strategies in mining *** primary objective is to characterize OM by identifying its elemental composition,thermal maturity,functional groups,and soluble fractions;and extract gold from OM using a two-step sequential extraction method(hydrogen peroxide and aqua regia)combined with geochemical *** and experimental results from samples of both ore deposits indicate the presence of finely disseminated solid bitumen and reworked vitrinite,originating from thermally matured(RmcRo%—3.76 in Bakyrchik;Ro%—2.25 in W-Mecsek)terrigenous high *** deposits exhibit extremely low extractable bitumen yield and TOC(0.34%in Bakyrchik;0.25 wt%in W-Mecsek),characterized by an aromatic carboxylic acid organic structure and a composition rich in sulfur-containing(1.17%in Bakyrchik;5.81%in W-Mecsek)aromatic *** occurrence and enrichment within OM were confi rmed through the sequential extraction method employing ICP-OES and LA-ICP-MS *** sequentially extracted gold content from OM reached up to 3 ppm in Bakyrchik and up to 3.28 ppm in Western Mecsek,accompanied by Ag(ranging from 0.01 to 0.32 ppm).Higher concentrations of Au(4 ppm)and Ag(27 ppm)were extracted from residue materials,which are likely associated with sulfide *** presence of gold in OM was further validated using *** bonding within OM struc

关键词： Bakyrchik Western Mecsek Solid bitumen Reworked vitrinite Gold

Bi-directional interaction of joint shear strength in non-seismically designed corner RC beam-column connections under seismic loading

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2025年第1期24卷 135-153页

作者： mohammad Amir Najafgholipour Negin Ahmadi rad Akanshu Sharma Department of Civil and Environmental Engineering Shiraz University of TechnologyShiraz ***Iran Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907-2050USA

Non-seismically designed(NSD)beam-column joints are susceptible to joint shear failure under seismic *** significant research is available on the seismic behavior of such joints of planar frames,the information on the seismic behavior of joints of space frames(3D joints)is *** 3D joints are subjected to bi-directional excitation,which results in an interaction between the shear strength obtained for the joint in the two orthogonal directions *** bi-directional seismic behavior of corner reinforced concrete(RC)joints is the focus of this ***,a detailed finite element(FE)model using the FE software Abaqus,is developed and validated using the test results from the *** validated modeling procedure is used to conduct a parametric study to investigate the influence of different parameters such as concrete strength,dimensions of main and transverse beams framing into the joint,presence or absence of a slab,axial load ratio and loading direction on the seismic behavior of *** subjecting the models to different combinations of loads on the beams along perpendicular directions,the interaction of the joint shear strength in two orthogonal directions is *** comparison of the interaction curves of the joints obtained from the numerical study with a quadratic(circular)interaction curve indicates that in a majority of cases,the quadratic interaction model can represent the strength interaction diagrams of RC beam to column connections with governing joint shear failure reasonably well.

关键词： beam-column joints joint shear failure bidirectional loading interaction curve finite element study

Promising effects of Persian shallot extract on the serum markers and blood pressure of patients with metabolic syndrome:a double-blinded randomized controlled trial

在线全文

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2025年第1期45卷 100-106页

作者： Neda Naimipoor Zahra Bagheri-Hosseinabadi mohammad Reza Hajizadeh Mitra Abbasifard mohammad Reza Mirzaei Akram Ghadiri Anari Maryam mohammad-Sadeghipour Mehdi Mahmoodi Department of Clinical Biochemistry School of MedicineRafsanjan University of Medical Sciences Department of Internal Medicine School of MedicineAli-Ibn Abi-Talib HospitalRafsanjan University of Medical Sciences Molecular Medicine Research Center Research Institute of Basic Medical SciencesRafsanjan University of Medical Sciences Diabetes Research Center Shahid Sadoughi University of Medical Sciences Department of Clinical Biochemistry Afzalipour School of MedicineKerman University of Medical Sciences Physiology Research Center Institute of NeuropharmacologyKerman University of Medical Sciences

OBJECTIVE: To evaluate the effect of Persian shallot extract on the serum markers and blood pressure of patients with metabolic syndrome(MetS). METHODS: Fifty patients with Met S diagnosis were randomly assigned to the intervention(Persian shallot extract) and the control(placebo) group. Both groups received treatment for three months. Before the study and at the end of the study, 5 mL peripheral blood was taken from each patient. The measured factors included total antioxidant capacity(TAC), superoxide dismutase enzyme(SOD), malondialdehyde, oxidized low-density lipoprotein(Ox-LDL), apolipoprotein H(Apo-H), fasting blood glucose(FBS), total cholesterol, triglycerides, high-density lipoprotein(HDL), LDL, and systolic and diastolic blood pressure. RESULTS: At baseline, the evaluated parameters were not significantly different between the intervention and control groups. At the end of the study, the mean serum levels of malondialdehyde and ox-LDL were significantly lower in the intervention group. The mean FBS, cholesterol, triglycerides, and LDL were significantly lower in the intervention group. The mean TAC and HDL were significantly higher in the intervention group(P < 0.05). Moreover, the intervention group significantly reduced systolic and diastolic blood pressure. No other significant association was observed. CONCLUSION: Persian shallot extract has several beneficial effects in Met S patients, including optimizing oxidative balance, reducing blood pressure, fasting blood sugar, and blood lipid profile.

关键词： antioxidants medicine, Persian metabolic syndrome shallots

Influences of Financial Development and Energy Price on Renewable Energy:An Italian Case

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Energy Engineering 2025年第2期122卷 493-514页

作者： Asif Raihan mohammad Ridwan Mahdi Salehi Grzegorz Zimon Institute of Climate Change National University of MalaysiaBangi43600SelangorMalaysia Department of Economics Noakhali Science and Technology UniversityNoakhali3814Bangladesh Department of Economics and Administrative Sciences Ferdowsi University of MashhadMashhad***Iran Department of Finance Banking and AccountancyFaculty of ManagementRzeszow University of TechnologyRzeszow35-505Poland

Global climate change has created substantial difficulties in the areas of sustainability,development,and environmental conservation due to the widespread dependence on fossil fuels for energy ***,the promotion of renewable energy programs has the potential to significantly expedite endeavors aimed at tackling climate ***,it is essential to conduct a thorough analysis that considers the financial aspects to fully understand the main hurdles that are preventing the advancement of renewable energy *** is a leading country in the worldwide deployment of renewable *** objective of this research is to assess the impact of financial growth,economic progress,and energy expenses on Italy’s adoption of renewable energy *** employing the Auto-Regressive Distributed Lag(ARDL)technique,we analyzed annual data spanning from1990 to *** revealed that a 1%increase in financial and economic development would boost renewable energy consumption in the long run by 0.29%and 0.48%,***,a 1%increase in energy prices might reduce consumption of renewable energy by 0.05%in the long *** study’s primary significance lies in furnishing actionable strategies for Italy to augment green finance for renewable energy,fostering sustained social and economic ***,the analytical insights gleaned from this research offer valuable insights for energy-importing nations worldwide.

关键词： Renewable energy financial development economic growth energy prices sustainable development

Best Linear Controllers for Decentralized Linear Quadratic Systems

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 Systems Science & Complexity 2025年第01期 210-237页

作者： AFSHARI mohammad MAHAJAN Aditya Institute for Robotics and Intelligent Machines Georgia Institute of Technology Department of Electrical and Computer Engineering McGill University

In this paper, the authors revisit decentralized control of linear quadratic(LQ) *** of imposing an assumption that the process and observation noises are Gaussian, the authors assume that the controllers are restricted to be linear. The authors show that the multiple decentralized control models, the form of the best linear controllers is identical to the optimal controllers obtained under the Gaussian noise assumption. The main contribution of the paper is the solution ***, optimal controllers for decentralized LQ systems are identified using dynamic programming, maximum principle, or spectral decomposition. The authors present an alternative approach which is based by combining elementary building blocks from linear systems, namely, completion of squares, state splitting, static reduction, orthogonal projection,(conditional) independence of state processes, and decentralized estimation.

关键词：

Rainfall-induced wind erosion in soils stabilized with alkali-activated waste materials

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 465-480页

作者： Alireza Komaei Abbas Soroush Seyed mohammad Fattahi Hesam Ghanbari Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehran159163431Iran

This study evaluates the efficacy of sustainable erosion control using slag-based alkali-activated cement crusts under varying rainfall and wind conditions. The rainfall intensities ranged from 30 mm/h to 120 mm/h, with durations ranging from 15 min to 90 min, and crust slopes of ∼2° (gentle) and 30° (steep). Wind tunnel experiments were conducted at wind velocities of 14 m/s, 21 m/s, and 28 m/s to investigate post-rainfall wind erodibility, along with changes in crust strength and microstructure analysis. The findings show the development of hydrated cementitious phases in alkali-activated material, which form around and between the particles during the alkaline activation process. Alkali-activated cement crusts significantly reduced erosion caused by rainfall and subsequent wind by several orders of magnitude. At the highest rainfall intensity of 120 mm/h, rainfall erosion was measured to be 1654.81 kg/m2 for untreated samples and 0.89 kg/m2 for treated samples, demonstrating a substantial 99.95% reduction in erosion due to the treatment. Similarly, at the highest wind speed tested, wind erosion was 122.75 kg/m2 for untreated samples and 0.095 kg/m2 for treated samples, indicating a significant 99.92% reduction in erosion due to the formation of an alkali-activated cement crust on the soil surface. However, exposure of the samples to 120 mm/h rainfall for 90 min resulted in a 5.2-fold increase in wind erosion compared to pre-rainfall conditions. Similarly, penetrometer results indicated a 37%–54% reduction in post-rainfall surface strength.

关键词： Rainfall erosion Alkali-activated material Wind erosion Crust formation

Noncommutativity and its role in constant-roll inflation models with non-minimal coupling constrained by swampland conjectures

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

Chinese Physics C 2025年第02期 241-258页

作者： Saeed Noori Gashti mohammad Reza Alipour mohammad Ali S.Afshar Jafar Sadeghi School of Physics Damghan University Department of Physics Faculty of Basic SciencesUniversity of Mazandaran

In this paper, using Hamiltonian formalism, we obtain solutions for constant-roll inflation according to the noncommutativity and the non-minimal coupling field of the Lagrangian. We consider three different types of couplings: power-law, exponential, and logarithmic. Subsequently, by plotting some figures, we study the effects of these coupling in constant-roll inflation with noncommutative parameters. We identify and specify the permissible regions of each case of the swampland conjecture and determine the best model. We find that the exponential, logarithmic, and power-law couplings with θ>0 ar results in both cases, some of which are compatible and some incompatible with the dS swampland ***,θ>0 is more compatible than θ<0, and the consistency value in the second boundary condition is much higher than in the first. The order of better compatibility of couplings with the swampland conjecture is ranked as follows: exponential non-minimal coupling, logarithmic non-minimal coupling, and power-law non-minimal coupling. For each type of coupling, we calculate the values of the scalar spectral index n s and the tensor-to-scalar ratio r for two different potentials and compare them with the observational data from Planck 2018. We also determine the range of the free parameters(a, b, q)model consistent with the conjecture. We find that the model satisfies the FRDSSC for all types of couplings and both potentials, with some constraints on the parameters.

关键词：

Retinal capillary density among healthy Egyptian and South Asian students:an optical coherence tomography angiography study

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2025年第1期18卷 111-116页

作者： Abdussalam M Abdullatif Alimulhaq mohammad Moamnlhaq Tamer A.Macky Noha Ahmed Edris Department of Ophthalmology Kasr ElAini HospitalCairo UniversityCairo 1141Egypt

AIM:To compare the macular and optic nerve perfusion and vascular architecture using optical coherence tomography angiography(OCTA)in normal eyes of Egyptian(Caucasians)and South Asian(Asians)***:Cross-sectional analytical OCTA study performed on 90 eyes of South Asian(n=45)and Egyptians(n=45)were *** participants underwent bestcorrected visual acuity test,slit lamp,and fundus *** images;macular 6×6 mm^(2) grid and optic nerve 4.5×4.5 mm^(2) grid were used to examine the parafoveal and peripapillary regions,***:The mean capillary vessel density(CVD)in macular sectors among South Asians and Egyptians participants were(50.31%±2.53%,51.2%±5.93%)and(49.71%±3.6%,51.94%±4.79%)in superficial(SCP)and deep capillary plexuses(DCP),respectively(P>0.05).Mean CVD in both groups was higher in DCP compared to SCP in all sectors but was not significant(P>0.05).Mean foveal CVD increases with an increase in central retinal thickness in both SCP and DCP(P<0.001),among both *** area of the foveal avascular zone(FAZ)was 0.28±0.09 and 0.27±0.08 mm2 in South Asian and Egyptians,*** area decreases with an increase in the thickness and foveal CVD(P<0.001).Mean CVD in the peripapillary area was 48.23%±5.78% in South Asian and 49.52%±2.38% in Egyptian *** mean retinal nerve fiber layer thickness was found to be higher in the nasal quadrant among South Asian females than the Egyptian females(P<0.05).CONCLUSION:No significant racial disparity is found in this *** findings are helpful for assessing and improving the normative data on the differences in South Asian and Egyptian populations.

关键词： South Asian Egyptian optical coherence tomography angiography macular perfusion peripapillary vessel flow density