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Analytical models for evaluating buoyancy-driven ventilation due to stack effect in a shaft considering heat transfer from shaft interior boundaries 被引量:1
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作者 YANG Dong LI Bai—zhan +1 位作者 DU Tao LI Nan 《Journal of Central South University》 SCIE EI CAS 2012年第3期651-656,共6页
Stack effect is a dominant driving force for building natural ventilation.Analytical models were developed for the evaluation of stack effect in a shaft,accounting for the heat transfer from shaft interior boundaries.... Stack effect is a dominant driving force for building natural ventilation.Analytical models were developed for the evaluation of stack effect in a shaft,accounting for the heat transfer from shaft interior boundaries.Both the conditions with constant heat flux from boundaries to the airflow and the ones with constant boundary temperature were considered.The prediction capabilities of these analytical models were evaluated by using large eddy simulation(LES)for a hypothetical shaft.The results show that there are fairly good agreements between the predictions of the analytical models and the LES predictions in mass flow rate,vertical temperatures profile and pressure difference as well.Both the results of analytical models and LES show that the neutral plane could locate higher than one half of the shaft height when the upper opening area is identical with the lower opening area.Further,it is also shown that the analytical models perform better than KLOTE's model does in the mass flow rate prediction. 展开更多
关键词 stack effect theoretical analysis large eddy simulation vertical temperature distribution heat transfer
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A simple plume model induced by stack effect in a vertical shaft
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作者 Zhang Jingyan Lu Weizhen Huo Ran 《Engineering Sciences》 EI 2009年第3期35-40,共6页
After comparing the mechanism of tilted plume under stack effect with that of spill plume,the tilted plume model induced by stack effect in a vertical shaft is developed simply based on the theoretical results and a s... After comparing the mechanism of tilted plume under stack effect with that of spill plume,the tilted plume model induced by stack effect in a vertical shaft is developed simply based on the theoretical results and a series of full-scale tests. It is shown that the two sides of plume are symmetrical and have an accordant regulation that the plume radius has a linear relation to the height z. The profile of fire plume under stack effect is similar to the windblown flame in wind tunnel,and the range of flame deflection angle is about from 50 to 60 degree. 展开更多
关键词 stack effect tilted plume profile plume radius flame deflection angle air-entrainment
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Study on Stack Effect of Stairwell by Numerical Model of Leakage Flow through Gap of Door
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作者 Jung-Yup Kim Ji-Seok Kim 《Open Journal of Fluid Dynamics》 2013年第4期241-247,共7页
Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an anal... Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an analysis of the stack effect, analysis methods on the leakage flow through gap of interior door shall be formulated. Until now, studies related to the gap leakage flow in buildings have mainly analyzed flow field and pressure in the buildings one-dimensionally using pressure difference-leakage flowrate relations of Orifice Equation and a network numerical analysis algorithm that as- sumes each compartment in the buildings as a single point. In this study, the Momentum Loss Model which enables pressure drop to be proportional to the flow velocity through the gap of door in computational domain of 3-dimensional numerical analysis was proposed to reflect the gap flow phenomenon effectively in 3-dimensional numerical analysis. Using the proposed model, 3-dimensional numerical analysis of the stack effect on the stairs in buildings was performed, and the effects of separation door and lobby between stair and accommodation on the stack effect were investigated. 展开更多
关键词 stack effect LEAKAGE Flow GAP of DOOR MOMENTUM Loss Model Separation DOOR NUMERICAL Analysis
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Leakage Current Estimation of CMOS Circuit with Stack Effect 被引量:3
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作者 Yong-JunXu Zu-YingLuo +2 位作者 Xiao-WeiLi Li-JianLi Xian-LongHong 《Journal of Computer Science & Technology》 SCIE EI CSCD 2004年第5期708-717,共10页
Leakage current of CMOS circuit increases dramatically with the technologyscaling down and has become a critical issue of high performance system. Subthreshold, gate andreverse biased junction band-to-band tunneling (... Leakage current of CMOS circuit increases dramatically with the technologyscaling down and has become a critical issue of high performance system. Subthreshold, gate andreverse biased junction band-to-band tunneling (BTBT) leakages are considered three maindeterminants of total leakage current. Up to now, how to accurately estimate leakage current oflarge-scale circuits within endurable time remains unsolved, even though accurate leakage modelshave been widely discussed. In this paper, the authors first dip into the stack effect of CMOStechnology and propose a new simple gate-level leakage current model. Then, a table-lookup basedtotal leakage current simulator is built up according to the model. To validate the simulator,accurate leakage current is simulated at circuit level using popular simulator HSPICE forcomparison. Some further studies such as maximum leakage current estimation, minimum leakage currentgeneration and a high-level average leakage current macromodel are introduced in detail.Experiments on ISCAS85 and ISCAS89 benchmarks demonstrate that the two proposed leakage currentestimation methods are very accurate and efficient. 展开更多
关键词 computer-aided design leakage current estimation stack effect MACROMODELING propagation of signal probability
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Basal-plane stacking-fault energies of Mg alloys: A first-principles study of metallic alloying effects 被引量:9
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作者 Qing Dong Zhe Luo +6 位作者 Hong Zhu Leyun Wang Tao Ying Zhaohui Jin Dejiang Li Wenjiang Ding Xiaoqin Zeng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第10期1773-1780,共8页
Generalized stacking-fault energies (GSFEs) of basal-plane stacking faults 11 and 12 in Mg alloys have been studied based on first-principles calculations, where 43 alloying elements were considered. It is found tha... Generalized stacking-fault energies (GSFEs) of basal-plane stacking faults 11 and 12 in Mg alloys have been studied based on first-principles calculations, where 43 alloying elements were considered. It is found that the most contributing features of alloying elements to GSFEs are bulk modulus, equilibrium volume, binding energy, atomic radius and ionization energy. Both bulk modulus and ionization energy exhibit positive relationships with GSFEs, and the others show opposite relationships. Multiple regressions have been performed to offer a quantitative prediction for basal-plane GSFEs in Mg-X systems. GSFEs, alloying effects of elements and the prediction model established within this work may provide guidelines for new Mg alloys design with better ductility. 展开更多
关键词 First-principles calculations Magnesium alloys stacking-fault energy Alloying effect
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STUDY ON THE STABILITY AND STACKING INTERACTION EFFECT OF THE TERNARY M(Ⅱ)(ATP)AND PYRIDINE-LIKE LIGANDS
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作者 Bin SONG Jie ZHANG Fu Hai WU Liang Nian JI Biotechnology Research Center,Chemistry Department Zhongshan University,Guangzhou 510275 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1097-1100,共4页
The stabilities of the complexes of three pyridine-like ligands with M(II)(ATP)^(2-) and M(II)(M=Ni,Co)were studied by spectrophotometry and by comparing the stability constants of the ternary complexes with these of ... The stabilities of the complexes of three pyridine-like ligands with M(II)(ATP)^(2-) and M(II)(M=Ni,Co)were studied by spectrophotometry and by comparing the stability constants of the ternary complexes with these of the binary complexes.A stacking interaction between the pyridine ring and the purine ring of ATP is indicated.The general existence of the stacking interaction encourages us to interpret the antitumor mechanism of a new class of antitumor drugs. 展开更多
关键词 ATP)AND PYRIDINE-LIKE LIGANDS STUDY ON THE STABILITY AND stackING INTERACTION effect OF THE TERNARY M
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Synergistic Effect of Alloying Atoms on Intrinsic Stacking-Fault Energy in Austenitic Steels 被引量:1
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作者 Ling-Hong Liu Tou-Wen Fan +3 位作者 Cui-Lan Wu Pan Xie Ding-Wang Yuan Jiang-Hua Chen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第3期272-279,共8页
Intrinsic stacking-fault energy is a critical parameter influencing the various mechanical performances of aus- tenitic steels with high Mn concentrations. However, quantitative calculations of the stacking-fault ener... Intrinsic stacking-fault energy is a critical parameter influencing the various mechanical performances of aus- tenitic steels with high Mn concentrations. However, quantitative calculations of the stacking-fault energy (SFE) of the face-centered cubic (fcc) Fe, including the changes in concentrations and geometrical distribution of alloying atoms, cannot be obtained by using previous computation models. On the basis of the interaction energy model, we evaluated the effects of a single alloying atom (i.e., Mn, A1, Si, C and N), as well as its aggregates, including the Mn-X dimer and Mn2-X trimer (X = A1, Si, C and N) on the SFE of the fcc Fe via first-principle calculations. Given low concentrations (〈10 wt%) of alloying atoms, dimers and trimers, theoretical calculations reveal the following: (1) Alloying atom Mn causes a decrease in the SFE, whereas A1, Si, C and N significantly increase the SFE; (2) combination with other alloying atoms to form the Mn-X dimer (X = A1, Si, C and N) exerts an effect on SFE that, to a certain extent, is close to that of the corresponding single X atom; (3) the interaction between Mnz-X and the stacking fault is stronger than that of the corresponding single X atom, inducing a significant increase in the SFE of fcc Fe. The theoretical results we obtained demonstrate that the increase in SFE in high-Mn steel originates from the synergistic effect of Mn and other trace alloy atoms. 展开更多
关键词 stacking-fault energy Synergism First-principle calculation Austenitic steel Alloying effect
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Oxygen Scavenging Effect of LaLuO_3/TiN Gate Stack in High-Mobility Si/SiGe/SOI Quantum-Well Transistors
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作者 冯锦锋 刘畅 +1 位作者 俞文杰 彭颖红 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期108-110,共3页
Higher-s dielectric LaLuO3, deposited by molecular beam deposition, with TiN as gate stack is integrated into high-mobility Si/SiGe/SOI quantum-well p-type metal-oxide-semiconduetor field effect transistors. Threshold... Higher-s dielectric LaLuO3, deposited by molecular beam deposition, with TiN as gate stack is integrated into high-mobility Si/SiGe/SOI quantum-well p-type metal-oxide-semiconduetor field effect transistors. Threshold voltage shift and capacitance equivalent thickness shrink are observed, resulting from oxygen scavenging effect in LaLuO3 with ti-rich TiN after high temperature annealing. The mechanism of oxygen scavenging and its potential for resistive memory applications are analyzed and discussed. 展开更多
关键词 SOI SiGe TIN Oxygen Scavenging effect of LaLuO3/TiN Gate stack in High-Mobility Si/SiGe/SOI Quantum-Well Transistors of in Gate
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Stacked lateral double-diffused metal–oxide–semiconductor field effect transistor with enhanced depletion effect by surface substrate
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作者 Qi Li Zhao-Yang Zhang +3 位作者 Hai-Ou Li Tang-You Sun Yong-He Chen Yuan Zuo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第3期328-332,共5页
A stacked lateral double-diffused metal–oxide–semiconductor field-effect transistor(LDMOS) with enhanced depletion effect by surface substrate is proposed(ST-LDMOS), which is compatible with the traditional CMOS pro... A stacked lateral double-diffused metal–oxide–semiconductor field-effect transistor(LDMOS) with enhanced depletion effect by surface substrate is proposed(ST-LDMOS), which is compatible with the traditional CMOS processes. The new stacked structure is characterized by double substrates and surface dielectric trenches(SDT). The drift region is separated by the P-buried layer to form two vertically parallel devices. The doping concentration of the drift region is increased benefiting from the enhanced auxiliary depletion effect of the double substrates, leading to a lower specific on-resistance(Ron,sp). Multiple electric field peaks appear at the corners of the SDT, which improves the lateral electric field distribution and the breakdown voltage(BV). Compared to a conventional LDMOS(C-LDMOS), the BV in the ST-LDMOS increases from 259 V to 459 V, an improvement of 77.22%. The Ron,sp decreases from 39.62 m?·cm^2 to 23.24 m?·cm^2 and the Baliga's figure of merit(FOM) of is 9.07 MW/cm^2. 展开更多
关键词 double substrates SURFACE dielectric TRENCH stacked LATERAL double-diffused metal–oxide– SEMICONDUCTOR field-effect transistor(ST-LDMOS) breakdown voltage
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Predicting air pressure in drainage stack of high-rise building 被引量:1
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作者 E. S. W. WONG 李应林 朱祚金 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第3期351-362,共12页
It is necessary to understand the features of air pressure in a drainage stack of a high-rise building for properly designing and operating a drainage system. This paper presents a mathematical model for predicting th... It is necessary to understand the features of air pressure in a drainage stack of a high-rise building for properly designing and operating a drainage system. This paper presents a mathematical model for predicting the stack performance. A step function is used to describe the effect of the air entrainment caused by the water discharged from branch pipes. An additional source term is introduced to reflect the gas-liquid interphase interaction (GLII) and stack base effect. The drainage stack is divided into upper and base parts. The air pressure in the upper part is predicted by a total variation diminishing (TVD) scheme, while in the base part, it is predicted by a characteristic line method (CLM). The predicted results are compared with the data measured in a real-scale high- rise test building. It is found that the additional source term in the present model is effective. It intensively influences the air pressure distribution in the stack. The air pressure is also sensitive to the velocity-adjusting parameter (VAP), the branch pipe air entrainment, and the conditions on the stack bottom. 展开更多
关键词 air pressure in drainage stack characteristic line method stack base effect interphase interaction
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An Improved SOI CMOS Technology Based Circuit Technique for Effective Reduction of Standby Subthreshold Leakage 被引量:1
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作者 Manish Kumar Md. Anwar Hussain Sajal K. Paul 《Circuits and Systems》 2013年第6期431-437,共7页
Silicon-on-insulator (SOI) CMOS technology is a very attractive option for implementing digital integrated circuits for low power applications. This paper presents migration of standby subthreshold leakage control tec... Silicon-on-insulator (SOI) CMOS technology is a very attractive option for implementing digital integrated circuits for low power applications. This paper presents migration of standby subthreshold leakage control technique from a bulk CMOS to SOI CMOS technology. An improved SOI CMOS technology based circuit technique for effective reduction of standby subthreshold leakage power dissipation is proposed in this paper. The proposed technique is validated through design and simulation of a one-bit full adder circuit at a temperature of 27℃, supply voltage, VDD of 0.90 V in 120 nm SOI CMOS technology. Existing standby subthreshold leakage control techniques in CMOS bulk technology are compared with the proposed technique in SOI CMOS technology. Both the proposed and existing techniques are also implemented in SOI CMOS technology and compared. Reduction in standby subthreshold leakage power dissipation by reduction factors of 54x and 45x foraone-bit full adder circuit was achieved using our proposed SOI CMOS technology based circuit technique in comparison with existing techniques such as MTCMOS technique and SCCMOS technique respectively in CMOS bulk technology. Dynamic power dissipation was also reduced significantly by using this proposed SOI CMOS technology based circuit technique. Standby subthreshold leakage power dissipation and dynamic power dissipation were also reduced significantly using the proposed circuit technique in comparison with other existing techniques, when all circuit techniques were implemented in SOI CMOS technology. All simulations were performed using Microwindver 3.1 EDA tool. 展开更多
关键词 STANDBY SUBTHRESHOLD LEAKAGE SOI Technology Low Power MULTI-THRESHOLD VOLTAGE stack effect Reverse Gate VOLTAGE
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Mechanism of floating body effect mitigation via cutting off source injection in a fully-depleted silicon-on-insulator technology 被引量:2
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作者 黄鹏程 陈书明 陈建军 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期283-289,共7页
In this paper, the effect of floating body effect (FBE) on a single event transient generation mechanism in fully depleted (FD) silicon-on-insulator (SOI) technology is investigated using three-dimensional techn... In this paper, the effect of floating body effect (FBE) on a single event transient generation mechanism in fully depleted (FD) silicon-on-insulator (SOI) technology is investigated using three-dimensional technology computer-aided design (3D- TCAD) numerical simulation. The results indicate that the main SET generation mechanism is not carder drift/diffusion but floating body effect (FBE) whether for positive or negative channel metal oxide semiconductor (PMOS or NMOS). Two stacking layout designs mitigating FBE are investigated as well, and the results indicate that the in-line stacking (IS) layout can mitigate FBE completely and is area penalty saving compared with the conventional stacking layout. 展开更多
关键词 floating body effect in-line stacking SILICON-ON-INSULATOR source injection
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基于改进Stacking集成学习方法的武器装备体系作战效能预测 被引量:7
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作者 李驰运 缪建明 沈丙振 《兵工学报》 EI CAS CSCD 北大核心 2023年第11期3455-3464,共10页
作战效能预测对武器装备体系从建设、生产到实战的全过程都具有重要意义。在Stacking集成学习模型的基础上,优化模型对数据的交叉验证方式,针对原有模型次级学习器输入向量较为稀疏的问题,为次级学习层的输入增加多项式特征和经主成分... 作战效能预测对武器装备体系从建设、生产到实战的全过程都具有重要意义。在Stacking集成学习模型的基础上,优化模型对数据的交叉验证方式,针对原有模型次级学习器输入向量较为稀疏的问题,为次级学习层的输入增加多项式特征和经主成分分析法降维后的各项作战仿真数据指标(原始数据),形成一种改进Stacking集成学习模型的装备体系作战效能预测方法。以合成营攻占某一阵地的作战效能预测为例,验证该方法的有效性。 展开更多
关键词 武器装备体系 stacking集成学习 机器学习 作战效能预测 要点夺控
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基于红外焦平面读出电路应用的多层stack电容设计及SPICE模型研究
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作者 叶伟 戴佼容 +1 位作者 刘斯扬 孙伟锋 《航空兵器》 2014年第4期49-53,共5页
基于0.5μm CMOS工艺设计并制备了一种应用于红外焦平面读出电路的多层堆叠(stack)电容结构,测试结果表明,相比单一形式电容,stack电容的单位面积值增大两倍以上,因而能够有效地提升红外焦平面读出电路的电荷存储能力。此外,本文还为设... 基于0.5μm CMOS工艺设计并制备了一种应用于红外焦平面读出电路的多层堆叠(stack)电容结构,测试结果表明,相比单一形式电容,stack电容的单位面积值增大两倍以上,因而能够有效地提升红外焦平面读出电路的电荷存储能力。此外,本文还为设计的多层stack电容建立了一套描述其电学特性的SPICE模型,模型均方根误差在2%以内,因此可以准确描述stack电容的电学特性,满足了红外焦平面读出电路的仿真设计要求。 展开更多
关键词 红外焦平面读出电路 stack电容 SPICE模型 BSIM3 V3模型 边缘效应
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Study on two-dimensional analytical models for symmetrical gate stack dual gate strained silicon MOSFETs 被引量:1
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作者 李劲 刘红侠 +2 位作者 李斌 曹磊 袁博 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期492-498,共7页
Based on the exact resultant solution of two-dimensional Poisson's equation, the novel two-dimensional models, which include surface potential, threshold voltage, subthreshold current and subthreshold swing, have bee... Based on the exact resultant solution of two-dimensional Poisson's equation, the novel two-dimensional models, which include surface potential, threshold voltage, subthreshold current and subthreshold swing, have been developed for gate stack symmetrical double-gate strained-Si MOSFETs. The models are verified by numerical simulation. Besides offering the physical insight into device physics, the model provides the basic designing guidance of further immunity of short channel effect of complementary metal-oxide-semiconductor (CMOS)-based device in a nanoscale regime. 展开更多
关键词 STRAINED-SI gate stack double-gate MOSFETs short channel effect the drain-inducedbarrier-lowering
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A two-dimensional analytical modeling for channel potential and threshold voltage of short channel triple material symmetrical gate Stack(TMGS) DG-MOSFET
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作者 Shweta Tripathi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第10期518-524,共7页
In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along wit... In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along with triple material gate having different work functions and symmetrical gate stack structure, showcases substantial betterment in quashing short channel effects to a good extent. The device functioning amends in terms of improved exemption to threshold voltage roll-off, thereby suppressing the short channel effects. The encroachments of respective device arguments on the threshold voltage of the proposed structure are examined in detail. The significant outcomes are compared with the numerical simulation data obtained by using 2D ATLAS;device simulator to affirm and formalize the proposed device structure. 展开更多
关键词 triple material symmetrical gate stack(TMGS) DG MOSFET gate stack short channel effect drain induced barrier lowering threshold voltage
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THE FAILURE MECHANISM OF REVERSE SHAPE MEMORYEFFECT IN A Cu-BASE ALLOY
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作者 C.M Li G.X. Dong +1 位作者 S.T- Dai and D. Y Chen (Tsinghua University Beijing 100084, China)J Yin and D.X. Hu (Shanghai No.5 Steel Works, Shanghai 200940, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第3期203-205,共3页
The interior structural evolution accompanying reverse shape memory effect (RSMEin a Cu-Zn-Al alloy was studied by means of transmission electron microscopy. It was found that RSME is closely related to bainitic trans... The interior structural evolution accompanying reverse shape memory effect (RSMEin a Cu-Zn-Al alloy was studied by means of transmission electron microscopy. It was found that RSME is closely related to bainitic transformation in this alloy during the isothermal reaction at moderate temperatures. At a given temperature and a certain external constraint stress, the shape memory effect depends mainly on the aging time.During the early stage, the shape memory effect enhances with the increase of reactiotn time. Then it will decrease gradually apon further aging. If the alloy is overaged, the stacking faults of bainite will disappear gradually by the motion of partial dislocations through which long range diffusion of solute atoms takes place, giving rise to the deterioration of RSME. When all the bainite transforms to α phase, RSME will lose completely. 展开更多
关键词 reverse shape memory effect Cu-base alloy stacking fault BAINITE
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层错能对中锰钢包辛格效应的影响
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作者 冯毅 蔡志辉 +2 位作者 王辉 黄光杰 马鸣图 《机械工程材料》 北大核心 2025年第7期58-63,共6页
通过调整碳、锰和铝含量获得层错能分别为16,63 mJ·m^(-2)的2种中锰钢,采用1次拉-压加载试验研究了不同加载工况(拉伸/压缩应变分别为4%/8%,6%/10%,8%/12%)下层错能对包辛格效应的影响。结果表明:不同加载工况下,较大层错能中锰钢... 通过调整碳、锰和铝含量获得层错能分别为16,63 mJ·m^(-2)的2种中锰钢,采用1次拉-压加载试验研究了不同加载工况(拉伸/压缩应变分别为4%/8%,6%/10%,8%/12%)下层错能对包辛格效应的影响。结果表明:不同加载工况下,较大层错能中锰钢的压缩屈服强度降低比率(拉压屈服强度差与拉伸屈服强度之比)和包辛格应力参数(最大应力与压缩屈服强度差的绝对值与最大应力之比)均较小,包辛格比(最大应力与压缩屈服强度差的绝对值和最大应力与拉伸屈服强度差的绝对值之比)较大,背应力较小,相间塑性应变不兼容水平较低,包辛格效应较弱;随着拉伸/压缩应变增加,较小层错能中锰钢的包辛格效应增强,较大层错能中锰钢的包辛格效应几乎不变,对应变不敏感。 展开更多
关键词 中锰钢 包辛格效应 背应力 层错能 相间应力
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基于电磁超声的铁质文物特征提取方法研究
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作者 姚恩涛 路璐 +1 位作者 石玉 王平 《测控技术》 2025年第2期18-25,共8页
传统文物鉴定通常凭借个人经验,从文物材质、外观等方面着手,对文物真伪进行鉴定,该方法存在一定的局限性。针对铁质文物,根据材料的磁致伸缩特性取决于材料的微观结构的特点,利用具有磁致伸缩效应的电磁超声检测其特征参数,提出了一种... 传统文物鉴定通常凭借个人经验,从文物材质、外观等方面着手,对文物真伪进行鉴定,该方法存在一定的局限性。针对铁质文物,根据材料的磁致伸缩特性取决于材料的微观结构的特点,利用具有磁致伸缩效应的电磁超声检测其特征参数,提出了一种铁质文物的特征参数提取方法;利用电磁超声信号幅值随偏置磁场强度变化曲线,通过堆叠稀疏自编码器提取该曲线的特征参数用于文物的特征表达,并使用支持向量机(Support Vector Machine, SVM)分类算法进行辨识。采用该方法对3个不同的样件进行了实验验证,检测准确率达到93.3%,表明该方法对铁质文物的鉴定具有可行性。 展开更多
关键词 电磁超声 铁质文物 堆叠稀疏自编码器 磁致伸缩效应
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地震岩石物理建模技术在储层“甜点”预测中的应用--以南海某油田古近系储层为例
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作者 李春雷 《石油地质与工程》 2025年第4期18-26,共9页
针对特殊岩性组分导致的致密砂岩储层"甜点"预测难题,以南海某油田古近系储层为研究对象,开展钙质、凝灰质成分复合影响下的储层“甜点”预测技术研究。首先基于微分等效介质理论构建多矿物岩石物理模型,通过正演模拟获取研... 针对特殊岩性组分导致的致密砂岩储层"甜点"预测难题,以南海某油田古近系储层为研究对象,开展钙质、凝灰质成分复合影响下的储层“甜点”预测技术研究。首先基于微分等效介质理论构建多矿物岩石物理模型,通过正演模拟获取研究区探井的纵波速度、横波速度以及密度响应特征;再系统分析纵波阻抗、横波阻抗、密度、纵横波速度比及泊松比等弹性参数与泥质含量、钙质含量、凝灰质含量及孔隙度的多维响应关系,建立基于弹性参数交会分析的复杂岩性解释模板;最后结合叠前同时反演技术,实现钙质砂岩、凝灰质砂岩等致密储层与优质储层的三维空间刻画。经实践应用证实预测结果与验证井吻合率较高。研究结果表明,基于地震岩石物理的弹性参数敏感性分析可有效厘清复杂岩性储层的岩性、物性、岩石物理响应机制,可为致密砂岩甜点预测提供可靠的技术路径。 展开更多
关键词 岩石物理模型 岩石物理 致密砂岩 微分等效介质模型 叠前同时反演
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