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Self-adapting extraction of matrix mineral bulk modulus and verification of fluid substitution 被引量:5
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作者 林凯 熊晓军 +4 位作者 杨晓 贺振华 曹俊兴 张玺华 王萍 《Applied Geophysics》 SCIE CSCD 2011年第2期110-116,176,共8页
Gassmann's equations are commonly used for predicting seismic wave velocity in rock physics research.However the input matrix mineral bulk modulus parameters are not accurate,which greatly influences the prediction r... Gassmann's equations are commonly used for predicting seismic wave velocity in rock physics research.However the input matrix mineral bulk modulus parameters are not accurate,which greatly influences the prediction reliability.In this paper,combining the Russell fluid factor with the Gassman-Biot-Geertsma equation and introducing the dry-rock Poisson's ratio,we propose an effective matrix mineral bulk modulus extraction method.This method can adaptively invert the equivalent matrix mineral bulk modulus to apply the Gassmann equation to fluid substitution of complex carbonate reservoirs and increase the fluid prediction reliability.The verification of the actual material fluid substitution also shows that this method is reliable,efficient,and adaptable. 展开更多
关键词 self-adapting matrix mineral bulk modulus fluid substitution dry rock Poisson's ratio
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Low-velocity Impact Damage Analysis of Composite Laminates Using Self-adapting Delamination Element Method 被引量:1
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作者 王立朋 燕瑛 +1 位作者 吴大方 吴浩 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第4期313-319,共7页
On the basis ofa 2D 4-node Mindlin shell element method, a novel self-adapting delamination finite element method is presented, which is developed to model the delamination damage of composite laminates. In the method... On the basis ofa 2D 4-node Mindlin shell element method, a novel self-adapting delamination finite element method is presented, which is developed to model the delamination damage of composite laminates. In the method, the sublaminate elements are generated automatically when the delamination damage occurs or extends. Thus, the complex process and state of delamination damage can be simulated practically with high efficiency for both analysis and modeling. Based on the self-adapting delamination method, linear dynamic finite element damage analysis is performed to simulate the low-velocity impact damage process of three types of mixed woven composite laminates. Taking the frictional force among sublaminations during delaminating and the transverse normal stress into account, the analytical results are consistent with those of the experimental data. 展开更多
关键词 self-adapting delamination element method low-velocity impact DELAMINATION composite laminate
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Self-adapting control parameters modifieddifferential evolution for trajectoryplanning of manipulators 被引量:12
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作者 Lianghong WU Yaonan WANG Shaowu ZHOU 《控制理论与应用(英文版)》 EI 2007年第4期365-373,共9页
Control parameters of original differential evolution (DE) are kept fixed throughout the entire evolutionary process. However, it is not an easy task to properly set control parameters in DE for different optiinizat... Control parameters of original differential evolution (DE) are kept fixed throughout the entire evolutionary process. However, it is not an easy task to properly set control parameters in DE for different optiinization problems. According to the relative position of two different individual vectors selected to generate a difference vector in the searching place, a self-adapting strategy for the scale factor F of the difference vector is proposed. In terms of the convergence status of the target vector in the current population, a self-adapting crossover probability constant CR strategy is proposed. Therefore, good target vectors have a lower CFI while worse target vectors have a large CFI. At the same time, the mutation operator is modified to improve the convergence speed. The performance of these proposed approaches are studied with the use of some benchmark problems and applied to the trajectory planning of a three-joint redundant manipulator. Finally, the experiment results show that the proposed approaches can greatly improve robustness and convergence speed. 展开更多
关键词 self-adapting control parameters Differential evolution Redundant manipulator Trajectory planning
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Determination of Feature Line Equation for Self-adapting Incremental Press Bending 被引量:4
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作者 JinsongLIU ShihongZHANG +5 位作者 YuansongZENG ZhiqiangLI WeiWU ZhongtangWANG YiXU LimeiREN 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第6期739-742,共4页
The basie idea and method about determination of the feature line equations and how to apply them to the numerical control of the press bending of panei skins were introduced. Research indicates that it is feasible to... The basie idea and method about determination of the feature line equations and how to apply them to the numerical control of the press bending of panei skins were introduced. Research indicates that it is feasible to realize the self adapting incremental press bending by adopting the feature line equation. The feature line equation, which is based on the database of the status of practical processes, can be adjusted in time, and the forming precision can be improved. It is important to correctly select and reasonably predict the feature line equations to enhance the accuracy of the incremental press bending based on the feature line database and algorithm. The determination of the feature line equation settles necessary data foundation for further research on the database of self-adapting incremental press bending, and it supplies a new clue for the development of self-adapting incremental press bending. 展开更多
关键词 self-adapting IncrementaI press bending Feature line equation Panei skin
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A protein-enabled protective film with functions of self-adapting and anion-anchoring for stabilizing lithium-metal batteries 被引量:2
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作者 Chenxu Wang Xuewei Fu +2 位作者 Shengnan Lin Jin Liu Wei-Hong Zhong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期485-495,I0013,共12页
Practical implementations of rechargeable lithium(Li)metal batteries have long been plagued by multiple problems of Li anode,such as Li dendrite growth,large volume change,low Coulombic efficiency.Here,we report a pro... Practical implementations of rechargeable lithium(Li)metal batteries have long been plagued by multiple problems of Li anode,such as Li dendrite growth,large volume change,low Coulombic efficiency.Here,we report a protein-enabled film that can provide effective protection for Li metal.The protective film with an integrated design of high flexibility,strong adhesion and high Li-ion transference number(0.80)is fabricated by incorporating denatured zein(corn protein)with polyethylene oxide(PEO)acting as an age nt for sustaining the denatured protein chains against refolding via the intermolecular interactions between them.Thus,a conformable zein-enabled protective film(zein@PEO)with simultaneous en hancement in flexibility,modulus and adhesion strength is gen erated to offer both functi ons of self-adapting and anion-anchoring abilities.The results show that the zein@PEO film is able to accommodate the volume change,reduce the side reactions,and homogenize the ion deposition.Benefiting from these significant properties/fu nctions,the Li/Cu cell with the zein@PEO film delivers prolonged cycle life for over 500 hours with stable performance.Paired with LiMn_(2)O_(4) cathode,the capacity,cycle stability and rate performance of the cell are remarkably improved as well,demonstrati ng the effectiveness in stabilizing Li metal batteries. 展开更多
关键词 ZEIN self-adapting FLEXIBILITY Lithium metal Lithium dendrite
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Weighted Self-Adaptive Threshold Wavelets for Interpolation Point Selection Used in Interconnect MOR 被引量:1
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作者 Xinsheng Wang Mingyan Yu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第1期39-45,共7页
As process technology development,model order reduction( MOR) has been regarded as a useful tool in analysis of on-chip interconnects. We propose a weighted self-adaptive threshold wavelet interpolation MOR method on ... As process technology development,model order reduction( MOR) has been regarded as a useful tool in analysis of on-chip interconnects. We propose a weighted self-adaptive threshold wavelet interpolation MOR method on account of Krylov subspace techniques. The interpolation points are selected by Haar wavelet using weighted self-adaptive threshold methods dynamically. Through the analyses of different types of circuits in very large scale integration( VLSI),the results show that the method proposed in this paper can be more accurate and efficient than Krylov subspace method of multi-shift expansion point using Haar wavelet that are no weighted self-adaptive threshold application in interest frequency range,and more accurate than Krylov subspace method of multi-shift expansion point based on the uniform interpolation point. 展开更多
关键词 INTERCONNECT model order reduction HAAR wavelet transform WEIGHTED threshold multi-shift ARNOLDI circuit synthesis
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In-situ interfacial passivation and self-adaptability synergistically stabilizing all-solid-state lithium metal batteries 被引量:1
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作者 Huanhui Chen Xing Cao +6 位作者 Moujie Huang Xiangzhong Ren Yubin Zhao Liang Yu Ya Liu Liubiao Zhong Yejun Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期282-292,I0007,共12页
The function of solid electrolytes and the composition of solid electrolyte interphase(SEI)are highly significant for inhibiting the growth of Li dendrites.Herein,we report an in-situ interfacial passivation combined ... The function of solid electrolytes and the composition of solid electrolyte interphase(SEI)are highly significant for inhibiting the growth of Li dendrites.Herein,we report an in-situ interfacial passivation combined with self-adaptability strategy to reinforce Li_(0.33)La_(0.557)TiO_(3)(LLTO)-based solid-state batteries.Specifically,a functional SEI enriched with LiF/Li_(3)PO_(4) is formed by in-situ electrochemical conversion,which is greatly beneficial to improving interface compatibility and enhancing ion transport.While the polarized dielectric BaTiO_(3)-polyamic acid(BTO-PAA,BP)film greatly improves the Li-ion transport kinetics and homogenizes the Li deposition.As expected,the resulting electrolyte offers considerable ionic conductivity at room temperature(4.3 x 10~(-4)S cm^(-1))and appreciable electrochemical decomposition voltage(5.23 V)after electrochemical passivation.For Li-LiFePO_(4) batteries,it shows a high specific capacity of 153 mA h g^(-1)at 0.2C after 100 cycles and a long-term durability of 115 mA h g^(-1)at 1.0 C after 800 cycles.Additionally,a stable Li plating/stripping can be achieved for more than 900 h at 0.5 mA cm^(-2).The stabilization mechanisms are elucidated by ex-situ XRD,ex-situ XPS,and ex-situ FTIR techniques,and the corresponding results reveal that the interfacial passivation combined with polarization effect is an effective strategy for improving the electrochemical performance.The present study provides a deeper insight into the dynamic adjustment of electrode-electrolyte interfacial for solid-state lithium batteries. 展开更多
关键词 Solid-state lithium batteries Composite solid electrolyte In-situ polymerization Interfacial passivation layer self-adaptability
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A New Self-Adapting Admission Control Algorithm for Differential Service in Web Clusters
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作者 LIUAn-feng CHENZhi-gang LONGGuo-ping 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期749-754,共6页
A new admission control algorithm considering the network self-similar access characteristics is proposed. Taking advantage of the mathematical model of the network traffic admission control which can effectively over... A new admission control algorithm considering the network self-similar access characteristics is proposed. Taking advantage of the mathematical model of the network traffic admission control which can effectively overcome the self-similar characteristics of the network requests, through the scheduling of the differential service qucue based on priority while at the same time taking into account various factors including access characteristics of requests, load information, etc, smoothness of the admission control is ensured by the algorithm proposed in this paper. We design a non-linear self-adapting control algorithm by introducing an exponential admission function, thus overcomes the negative aspects introduced by static threshold parameters. Simulation results show that the scheme proposed in this paper can effectively improve the resource utilization of the clusters, while at the same time protecting the service with high priority. Our simulation results also show that this algorithm can improve system stability and reliability too. Key words Web cluster - admission control - differential service - self-similar - self-adapting CLC number TP 393 Foundation item: Supported by the National Natural Science Foundation of China (10375024) and the Hunan Natural Science Foundation of China(03JJY4054)Biography: LIU An-feng(1971-), male, Ph. D candidate, majoring in network computing, Web QoS. 展开更多
关键词 Web cluster admission control differential service SELF-SIMILAR self-adapting
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Self-adapting Scalable Differential Evolution Algorithm
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作者 刘荣辉 郑建国 《Journal of Donghua University(English Edition)》 EI CAS 2011年第4期384-390,共7页
Differential evolution(DE) demonstrates good convergence performance,but it is difficult to choose trial vector generation strategies and associated control parameter values.An improved method,self-adapting scalable D... Differential evolution(DE) demonstrates good convergence performance,but it is difficult to choose trial vector generation strategies and associated control parameter values.An improved method,self-adapting scalable DE(SSDE) algorithm,is proposed.Trial vector generation strategies and crossover probability are respectively self-adapted by two operators in this algorithm.Meanwhile,to enhance the convergence rate,vectors selected randomly with the optimal fitness values are introduced to guide searching direction.Benchmark problems are used to verify this algorithm.Compared with other well-known DE algorithms,experiment results indicate that this algorithm is better than other DE algorithms in terms of convergence rate and quality of optimization. 展开更多
关键词 differential evolution (DE) SCALABLE self-adapting parameter control function optimization
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Speed aware self-adapting and reconfigurable routing mechanism in MANET
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作者 Zhang Qinjuan Wu Muqing Zhen Yan 《High Technology Letters》 EI CAS 2012年第3期321-325,共5页
A self-adapting and reconfigurable routing mechanism is proposed according to the average moving speed of the nodes in mobile ad hoc network (MANET). This mechanism is based on the perception of moving speed and a p... A self-adapting and reconfigurable routing mechanism is proposed according to the average moving speed of the nodes in mobile ad hoc network (MANET). This mechanism is based on the perception of moving speed and a predesigned selection metric to choose the optimal routing protocol. The routing evaluation and selection metric is derived by OPNET simulations. AODV and OLSR are used as the example to show the process of this mechanism with the moving speed varying. The routing protocol can be configured without central configuration and human management. Besides, the overhead of the mechanism is reasonable and doesnot affect the quality of service (QoS) of the traffic in the network. Results show that the optimal routing protocol can be configured adaptively according to the speed so that better performance than end-to-end delay and packet delivery ratio. a specific protocol can be obtained in terms of 展开更多
关键词 speed aware self-adapting RECONFIGURATION mobile ad hoc network (MANET)
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Bidirectional rotating direct-current triboelectric nanogenerator with self-adaptive mechanical switching for harvesting reciprocating motion
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作者 Donghan Lee Joonmin Chae +6 位作者 Sumin Cho Jong Woo Kim Awais Ahmad Mohammad Rezaul Karim Moonwoo La Sung Jea Park Dongwhi Choi 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期324-335,共12页
Amid the growing interest in triboelectric nanogenerators(TENGs)as novel energy-harvesting devices,several studies have focused on direct current(DC)TENGs to generate a stable DC output for operating electronic device... Amid the growing interest in triboelectric nanogenerators(TENGs)as novel energy-harvesting devices,several studies have focused on direct current(DC)TENGs to generate a stable DC output for operating electronic devices.However,owing to the working mechanisms of conventional DC TENGs,generating a stable DC output from reciprocating motion remains a challenge.Accordingly,we propose a bidirectional rotating DC TENG(BiR-TENG),which can generate DC outputs,regardless of the direction of rotation,from reciprocating motions.The distinct design of the BiR-TENG enables the mechanical rectification of the alternating current output into a rotational-direction-dependent DC output.Furthermore,it allows the conversion of the rotational-direction-dependent DC output into a unidirectional DC output by adapting the configurations depending on the rotational direction.Owing to these tailored design strategies and subsequent optimizations,the BiR-TENG could generate an effective unidirectional DC output.Applications of the BiR-TENG for the reciprocating motions of swinging doors and waves were demonstrated by harnessing this output.This study demonstrates the potential of the BiR-TENG design strategy as an effective and versatile solution for energy harvesting from reciprocating motions,highlighting the suitability of DC outputs as an energy source for electronic devices. 展开更多
关键词 direct-current triboelectric nanogenerator mechanical rectification self-adaptive mechanical design harvesting reciprocation motion
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Ultrafast Response and Threshold Adjustable Intelligent Thermoelectric Systems for Next‑Generation Self‑Powered Remote IoT Fire Warning
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作者 Zhaofu Ding Gang Li +5 位作者 Yejun Wang Chunyu Du Zhenqiang Ye Lirong Liang Long‑Cheng Tang Guangming Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期413-428,共16页
Fire warning is vital to human life,economy and ecology.However,the development of effective warning systems faces great challenges of fast response,adjustable threshold and remote detecting.Here,we propose an intelli... Fire warning is vital to human life,economy and ecology.However,the development of effective warning systems faces great challenges of fast response,adjustable threshold and remote detecting.Here,we propose an intelligent self-powered remote IoT fire warning system,by employing single-walled carbon nanotube/titanium carbide thermoelectric composite films.The flexible films,prepared by a convenient solution mixing,display p-type characteristic with excellent high-temperature stability,flame retardancy and TE(power factor of 239.7±15.8μW m^(-1) K^(-2))performances.The comprehensive morphology and structural analyses shed light on the underlying mechanisms.And the assembled TE devices(TEDs)exhibit fast fire warning with adjustable warning threshold voltages(1–10 mV).Excitingly,an ultrafast fire warning response time of~0.1 s at 1 mV threshold voltage is achieved,rivaling many state-of-the-art systems.Furthermore,TE fire warning systems reveal outstanding stability after 50 repeated cycles and desired durability even undergoing 180 days of air exposure.Finally,a TED-based wireless intelligent fire warning system has been developed by coupling an amplifier,analogto-digital converter and Bluetooth module.By combining TE characteristics,high-temperature stability and flame retardancy with wireless IoT signal transmission,TE-based hybrid system developed here is promising for next-generation self-powered remote IoT fire warning applications. 展开更多
关键词 THERMOELECTRIC SELF-POWERED IoT fire warning Ultrafast response threshold adjustable
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Mixed Self-adapting GA Optimal Scheduling Algorithm for a Multiple Resource Job-shop
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作者 LI Shu-juan LI Yan LIU Zhi-gang 《International Journal of Plant Engineering and Management》 2007年第3期160-170,共11页
With an aim at the job-shop scheduling problem of multiple resource constraints, this paper presents mixed self-adapting Genetic Algorithm ( GA ) , and establishes a job-shop optimal scheduling model of multiple res... With an aim at the job-shop scheduling problem of multiple resource constraints, this paper presents mixed self-adapting Genetic Algorithm ( GA ) , and establishes a job-shop optimal scheduling model of multiple resource constraints based on the effect of priority scheduling rules in the heuristic algorithm upon the scheduling target. New coding regulations or rules are designed. The sinusoidal function is adopted as the self-adapting factor, thus making cross probability and variable probability automatically change with group adaptability in such a way as to overcome the shortcoming in the heuristic algorithm and common GA, so that the operation efficiency is improved. The results from real example simulation and comparison with other algorithms indicate that the mixed self-adapting GA algorithm can well solve the job-shop optimal scheduling problem under the constraints of various kinds of production resources such as machine-tools and cutting tools. 展开更多
关键词 heuristic rule mixed self-adapting GA multiple resource constraint optimal scheduling
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Vector Dominance with Threshold Searchable Encryption (VDTSE) for the Internet of Things
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作者 Jingjing Nie Zhenhua Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4763-4779,共17页
The Internet of Medical Things(IoMT)is an application of the Internet of Things(IoT)in the medical field.It is a cutting-edge technique that connects medical sensors and their applications to healthcare systems,which ... The Internet of Medical Things(IoMT)is an application of the Internet of Things(IoT)in the medical field.It is a cutting-edge technique that connects medical sensors and their applications to healthcare systems,which is essential in smart healthcare.However,Personal Health Records(PHRs)are normally kept in public cloud servers controlled by IoMT service providers,so privacy and security incidents may be frequent.Fortunately,Searchable Encryption(SE),which can be used to execute queries on encrypted data,can address the issue above.Nevertheless,most existing SE schemes cannot solve the vector dominance threshold problem.In response to this,we present a SE scheme called Vector Dominance with Threshold Searchable Encryption(VDTSE)in this study.We use a Lagrangian polynomial technique and convert the vector dominance threshold problem into a constraint that the number of two equal-length vectors’corresponding bits excluding wildcards is not less than a threshold t.Then,we solve the problem using the proposed technique modified in Hidden Vector Encryption(HVE).This technique makes the trapdoor size linear to the number of attributes and thus much smaller than that of other similar SE schemes.A rigorous experimental analysis of a specific application for privacy-preserving diabetes demonstrates the feasibility of the proposed VDTSE scheme. 展开更多
关键词 Internet of Things(IoT) Internet of Medical Things(IoMT) vector dominance with threshold searchable encryption(VDTSE) threshold comparison electronic healthcare
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Chalcogenide Ovonic Threshold Switching Selector
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作者 Zihao Zhao Sergiu Clima +4 位作者 Daniele Garbin Robin Degraeve Geoffrey Pourtois Zhitang Song Min Zhu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期1-40,共40页
Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimen... Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimensional phase change memory,stands out as one of the most promising candidates.The Optane with cross-point architecture is constructed through layering a storage element and a selector known as the ovonic threshold switch(OTS).The OTS device,which employs chalcogenide film,has thereby gathered increased attention in recent years.In this paper,we begin by providing a brief introduction to the discovery process of the OTS phenomenon.Subsequently,we summarize the key elec-trical parameters of OTS devices and delve into recent explorations of OTS materials,which are categorized as Se-based,Te-based,and S-based material systems.Furthermore,we discuss various models for the OTS switching mechanism,including field-induced nucleation model,as well as several carrier injection models.Additionally,we review the progress and innovations in OTS mechanism research.Finally,we highlight the successful application of OTS devices in three-dimensional high-density memory and offer insights into their promising performance and extensive prospects in emerging applications,such as self-selecting memory and neuromorphic computing. 展开更多
关键词 Non-volatile memory Ovonic threshold switch(OTS) CHALCOGENIDE SELECTOR
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Fractal model of spontaneous imbibition in low-permeability reservoirs coupled with heterogeneity of pore seepage channels and threshold pressure
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作者 Ming-Sheng Zuo Hao Chen +3 位作者 Xi-Liang Liu Hai-Peng Liu Yi Wu Xin-Yu Qi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1002-1017,共16页
Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability reservoirs.Due to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability res... Spontaneous imbibition(SI)is an important mechanism for enhancing oil recovery in low-permeability reservoirs.Due to the strong heterogeneity,and the non-Darcy flow,the construction of SI model for lowpermeability reservoirs is extremely challenging.Commonly,traditional SI models based on single or averaged capillary tortuosity ignore the influence of heterogeneity of pore seepage channels and the threshold pressure(TP)on imbibition.Therefore,in this work,based on capillary model and fractal theory,a mathematical model of characterizing SI considering heterogeneity of pore seepage channels is established.On this basis,the threshold pressure was introduced to determine the pore radius at which the wetted phase can displace oil.The proposed new SI model was verified by imbibition experimental data.The study shows that for weakly heterogeneous cores with permeability of 0-1 m D,the traditional SI model can characterize the imbibition process relatively accurately,and the new imbibition model can increase the coefficient of determination by 1.05 times.However,traditional model has serious deviations in predicting the imbibition recovery for cores with permeability of 10-50 m D.The new SI model coupling with heterogeneity of pore seepage channels and threshold pressure effectively solves this problem,and the determination coefficient is increased from 0.344 to 0.922,which is increased by2.68 times.For low-permeability reservoirs,the production of the oil in transitional pores(0.01-0.1μm)and mesopores(0.1-1μm)significantly affects the imbibition recovery,as the research shows that when the heterogeneity of pore seepage channels is ignored,the oil recovery in transitional pores and mesopores decreases by 7.54%and 4.26%,respectively.Sensitivity analysis shows that increasing interfacial tension,decreasing contact angle,oil-water viscosity ratio and threshold pressure will increase imbibition recovery.In addition,there are critical values for the influence of these factors on the imbibition recovery,which provides theoretical support for surfactant optimization. 展开更多
关键词 Spontaneous imbibition Low-permeability reservoir Fractal model threshold pressure Capillary tube
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A study of the soil water potential threshold values to trigger irrigation of ‘Shimizu Hakuto’ peach at pivotal fruit developmental stages
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作者 Yusui Lou Yuepeng Han +4 位作者 Yubin Miao Hongquan Shang Zhongwei Lv Lei Wang Shiping Wang 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期376-386,共11页
Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established man... Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit. 展开更多
关键词 PEACH Soil water potential Irrigation threshold Fruit expansion PHOTOSYNTHESIS
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Epidemic threshold influenced by non-pharmaceutical interventions in residential university environments
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作者 卢泽超 赵生妹 +1 位作者 束华中 巩龙延 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期551-556,共6页
The control of highly contagious disease spreading in campuses is a critical challenge.In residential universities,students attend classes according to a curriculum schedule,and mainly pack into classrooms,dining hall... The control of highly contagious disease spreading in campuses is a critical challenge.In residential universities,students attend classes according to a curriculum schedule,and mainly pack into classrooms,dining halls and dorms.They move from one place to another.To simulate such environments,we propose an agent-based susceptible–infected–recovered model with time-varying heterogeneous contact networks.In close environments,maintaining physical distancing is the most widely recommended and encouraged non-pharmaceutical intervention.It can be easily realized by using larger classrooms,adopting staggered dining hours,decreasing the number of students per dorm and so on.Their real-world influence remains uncertain.With numerical simulations,we obtain epidemic thresholds.The effect of such countermeasures on reducing the number of disease cases is also quantitatively evaluated. 展开更多
关键词 epidemic threshold susceptible-infected-recovered model non-pharmaceutical interventions time-varying heterogeneous contact networks
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Novel damage constitutive models and new quantitative identification method for stress thresholds of rocks under uniaxial compression
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作者 DU Kun YI Yang +3 位作者 LUO Xin-yao LIU Kai LI Peng WANG Shao-feng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2658-2675,共18页
Four key stress thresholds exist in the compression process of rocks,i.e.,crack closure stress(σ_(cc)),crack initiation stress(σ_(ci)),crack damage stress(σ_(cd))and compressive strength(σ_(c)).The quantitative id... Four key stress thresholds exist in the compression process of rocks,i.e.,crack closure stress(σ_(cc)),crack initiation stress(σ_(ci)),crack damage stress(σ_(cd))and compressive strength(σ_(c)).The quantitative identifications of the first three stress thresholds are of great significance for characterizing the microcrack growth and damage evolution of rocks under compression.In this paper,a new method based on damage constitutive model is proposed to quantitatively measure the stress thresholds of rocks.Firstly,two different damage constitutive models were constructed based on acoustic emission(AE)counts and Weibull distribution function considering the compaction stages of the rock and the bearing capacity of the damage element.Then,the accumulative AE counts method(ACLM),AE count rate method(CRM)and constitutive model method(CMM)were introduced to determine the stress thresholds of rocks.Finally,the stress thresholds of 9 different rocks were identified by ACLM,CRM,and CMM.The results show that the theoretical stress−strain curves obtained from the two damage constitutive models are in good agreement with that of the experimental data,and the differences between the two damage constitutive models mainly come from the evolutionary differences of the damage variables.The results of the stress thresholds identified by the CMM are in good agreement with those identified by the AE methods,i.e.,ACLM and CRM.Therefore,the proposed CMM can be used to determine the stress thresholds of rocks. 展开更多
关键词 stress threshold acoustic emission damage constitutive model damage element quantitative method
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CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening
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作者 Seo Yeon K. Orite Bryn Higuchi +1 位作者 Hyo-Chun Yoon Lana H. Gimber 《Open Journal of Radiology》 2024年第2期92-101,共10页
Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone min... Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies. 展开更多
关键词 OSTEOPOROSIS Bone Mineral Attenuation CT threshold
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