检索结果-南通市图书馆

A global comparison of V_(p),V_(s),and V_(p)/V_(s) structures of the mantle lithosphere beneath major cratons

Science China Earth Sciences 2023年第3期66卷 492-504页

作者： ehsan barzgar Fenglin NIU Shunping PEI State Key Laboratory of Petroleum Resources and Prospecting Unconventional Petroleum Research InstituteChina University of PetroleumBeijing 102249China Department of Earth Environmental and Planetary SciencesRice UniversityHouston 77005TexasUSA State Key Laboratory of Tibetan Plateau Earth System and Resources Environment Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Cratons formed due to the specific melting regime of the primitive mantle with elevated mantle temperature during ***,each craton has undergone a distinct evolution history,and some have lost their *** investigate to what degree cratons in comparison with one another have been modified from their analogous initial form,we employed Sn-Pn differential(PSn) traveltimes to derive Vp/Vsratio,which is thought to be related to Mg# of the *** assessed Pn,Sn,and PSn data using three datasets based on epicentral distance:(1) 2°–12°,(2) 2°–7°,and(3) 7°–12°.The results suggest that most cratons show comparable seismic properties with high velocities and low Vp/Vsratio,implying a highly depleted uppermost mantle that resembles the original residue from the partial melt extraction of the primitive mantle during the ***,the Eastern North China Craton(ENCC) displays the lowest P-and S-wave velocities,and noticeable high Vp/Vsratios in all datasets,implying a systematic difference with other *** observation suggests a scenario of total removal of the depleted Archean mantle lithosphere beneath the *** contrast,the Ordos Block located at the western part of the North China Craton(WNCC) shows velocities and Vp/Vsratio comparable with those of the typical cratons,suggesting that it has still maintained its Archean mantle *** Wyoming Craton has a high Vp/Vsratio similar to that of the ENCC and a high Pwave velocity comparable to that of the typical *** features suggest that the Archean mantle lithosphere has been significantly modified rather than totally removed and replaced by a younger fertile *** Indian Craton presents a low Vp/Vsratio and comparatively high velocities at shallow parts of the mantle lithosphere but a high Vp/Vsratio at deeper parts similar to that of the ENCC,suggesting a partial modification of the Indian Craton at deeper parts.

关键词： Craton Craton modification Mantle lithosphere North China Craton Wyoming Craton Indian Craton Vp/Vs ratio Seismic velocity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reservoirs Patterns and Key Controlling Factors of the Lenghu Oil & Gas Field in the Qaidam Basin, Northwestern China

引用

Journal of Earth Science 2021年第4期32卷 1011-1021页

作者： Wengang He ehsan barzgar Weiping Feng Liang Huang College of Engineering and Technology Zunyi Normal UniversityZunyi 563006China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China CNPC Logging International Beijing 102206China

The Lenghu area is one of the most crucial tectonic belts for oil and gas exploration in the Qaidam ***,reservoir distribution and the factors controlling petroleum accumulation in this area have not been studied in *** this paper,the structural characteristics and controlling factors of oil and gas accumulation in the Lenghu belt are investigated based on seismic profiles combined with drilling logs and microphotographs *** indicate that the Lenghu belt has thick source rocks and has preserved hydrocarbon generation ***,structural characteristics and lithology are the key factors controlling the reservoir *** production of oil and gas layers are mainly distributed in high structural points and weak stress *** fracture zones and the weak stress zones are the potential places for the distribution of oil and gas reservoirs.

关键词： Lenghu belt reservoir patterns controlling factor potential distribution zones

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deformation, Stratigraphy, Structures and Shortening of the Zagros Fold-Thrust Belt in Southwest Iran Analysis by Restoration

引用

Acta Geologica Sinica(English Edition) 2015年第1期89卷 105-120页

作者： ehsan barzgar Iraj ABDOLLAHIE FARD Rasoul HAMIDZADEH MOGHADAM Emadoddin ABDOLLAHIE KHALILI Aboozar GARAV Department of Mining Engineering Sahand University of Technology (SUT) Department of Petroleum Engineering Amirkabir University of Technology Department of Drilling Engineering Gubkin Russian State University of Oil and Gas

A structural cross-section constructed across the Zagros Fold-Thrust Belt covering the Abadan Plain, Dezful Embayment, and Izeh Zone applied 2D and 3D seismic data, well data, surface and subsurface geological maps, satellite images and field reconnaissance. Besides validation and modification of the cross-section, restoration allows better understanding of the geology, structural style and stratigraphy of the Zagros basin. In the area of interest, the Hormuz basal decollement and the Gachsaran detachment play the most significant roles in the structural style and deformation of the Zagros belt. More complexity is associated with interval decollements such as Triassic evaporites, Albian shales and Eocene marls. A variety of lithotectonic units and detachment surfaces confound any estimation of shortening, which generally decreases with increasing depth. Deformation completely differs in the Abadan Plain, Dezful Embayment and Izeh Zone because of different sedimentation histories and tectonic evolution; gentle and young structures can be interpreted as pre-collisional structures of the Dezful Embayment before the Late Cretaceous. After the Late Cretaceous, the Mountain Front Fault is the main control of sedimentation and deformation in the Zagros Basin, and this completely characterizes fold style and geometry within the Dezful Embayment and the Izeh Zone.

关键词： structural geology tectonics fold and thrust style restoration Iran

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantization and Event-Triggered Policy Design for Encrypted Networked Control

引用

IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 946-955页

作者： Yongxia Shi ehsan Nekouei the Department of Electrical Engineering City University of Hong KongHong KongChina

This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered *** to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before *** is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is *** handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the ***,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is *** doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be ***,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop ***,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results.

关键词： Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improving the Surface Roughness of Dental Implant Fixture by Considering the Size,Angle and Spraying Pressure of Sandblast Particles

引用

Journal of Bionic Engineering 2024年第1期21卷 303-324页

作者： ehsan Anbarzadeh Bijan Mohammadi School of Mechanical Engineering Iran University of Science and TechnologyTehranIran

In this study,different conditions of sandblasting on dental implant fixtures were investigated to achieve the best sandblasting conditions.18 different sandblasting conditions(Using 152 implant fixture samples)were examined,including parameters such as particle size,particle blasting pressure,and particle blasting *** surface treatment of the samples was performed using the SLA+Anodizing *** testing was performed for each of the 18 different states,and the average surface roughness of each of these was compared with each ***,a bone layer was placed on the sample with the closest average surface roughness to the standard and the least amount of aluminum oxide on its surface among the 18 different states,to confirm the accuracy and quality of the desired surface roughness by examining the bone formation process and *** results showed that state No.4(sandblast particle size:75µm,spraying pressure of sandblast particles:4 bar,sandblast particle spraying angle:30 degrees),which was prepared using the SLA+Anodizing method and had a surface roughness of 1.989µm(The percentage of Al_(2)O_(3)on the surface=6%),had the best sandblasting conditions and showed 95%cell viability and accelerated the treatment and bone formation process for about a *** simulation results,using Abaqus software,indicated that the stress distribution on the surface of the implant fixture in contact with the bone surface has increased by approximately 4.3%for state *** will help prevent loosening of the dental implant fixture over time.

关键词： Dental implants Surface treatment Sandblast Surface roughness Osseointegration

来源：

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

Bearing capacity of circular footings on multi-layered sand-waste tire shreds reinforced with geogrids

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1085-1094页

作者： Mahmoud Ghazavi ehsan Khosroshahi Faculty of Civil Engineering K.N.Toosi University of TechnologyTehranIran

The presence of waste tires poses an environmental challenge as they occupy a significant amount of land and are expensive to dispose in ***,reusing waste tires can address this issue when waste tires are used in geotechnical *** determine the viability of this approach,laboratoryscale tests were conducted to investigate load-bearing capacity of circular footings on sand-tire shred(STS)mixtures with shredded waste tire contents of 5%e15%by weight and three different widths of *** investigation focused on analyzing the thickness of layers composed of STS mixtures,the soil cap,and the impact of geogrids on bearing *** results indicate that a specific mixture of sand and tire shreds provides the highest footing-bearing *** addition,the optimal shred content and size were found to be 10%by weight and 2 cm×10 cm,***,for a given tire shred width,a particular length provides the largest bearing *** results agree well with that of previous research conducted by the first author and his colleagues in direct shear and California bearing ratio(CBR)*** primary finding of this research is that the use of two-layered STS mixtures reinforced by geogrids significantly enhances the bearing capacity.

关键词： Geogrid Sand Waste tire shred Bearing capacity Waste tire shred optimization Tire shred aspect ratio

来源：

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

Unveiling the potential impact of vitamin C in postoperative spinal pain

引用

中华神经外科杂志(英文) 2024年第3期10卷 1-6页

作者： Ranjbari Fatemeh Alimohammadi ehsan Clinical Research Development Center Taleghani and Imam Ali Hospital Kermanshah University of Medical Sciences Kermanshah Iran Department of Neurosurgery Kermanshah University of Medical Sciences Kermanshah Iran

Background Spinal surgery is a common procedure associated with significant postoperative pain, and identifying effective interventions to manage this pain is crucial for optimizing patient outcomes. This review assesses the existing literature to determine the overall impact of vitamin C supplementation on spinal postoperative *** Vitamin C could be considered a potentially beneficial adjunctive therapy for managing spinal postoperative pain, but its routine use requires further investigation.

关键词： Vitamin C Ascorbic acid Spinal surgery Postoperative pain Review article Background

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

引用

China Ocean Engineering 2024年第3期38卷 439-452页

作者： ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Predictive active control of building structures using LQR and artificial intelligence

引用

Earthquake Engineering and Engineering Vibration 2024年第2期23卷 489-502页

作者： Nirmal S.Mehta Vishisht Bhaiya K.A.Patel ehsan Noroozinejad Farsangi Department of Civil Engineering SVNIT SuratGujarat 395007India Urban Transformations Research Centre Western Sydney UniversityNSWAustralia

This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response *** on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the *** responses are determined by numerically analyzing the governing equation of motion using the state-space *** training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting *** study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage ***,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled *** trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage *** on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using ***,the LQRNN algorithm can replace conventional LQR control with the use of an active control system.

关键词： active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor resilience

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs

引用

Nano-Micro Letters 2024年第3期16卷 313-332页

作者： Mohsen Esmaeili ehsan Akbari Kyle George Gelareh Rezvan Nader Taheri‑Qazvini Monirosadat Sadati Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA TA Instruments Waters LLCNew CastleDE 19720USA Biomedical Engineering Program University of South CarolinaColumbiaSC 29208USA

Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living *** study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate *** designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed *** employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate *** techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow ***,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting *** insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral *** biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.

关键词： Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing Rheology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：