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Application of Time-Tracking Platform in the Reperfusion Treatment of Patients with Acute Ischemic Stroke in Primary Hospitals
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作者 Yaojie Cai Yan Chen +1 位作者 Feng Fu Yuping He 《Journal of Biosciences and Medicines》 2024年第7期230-238,共9页
Objective To explore the application effect of time tracking platform in improving the reperfusion treatment of patients with acute ischemic stroke in primary hospitals. Methods and Results Patients with acute ischemi... Objective To explore the application effect of time tracking platform in improving the reperfusion treatment of patients with acute ischemic stroke in primary hospitals. Methods and Results Patients with acute ischemic stroke who carried out emergency intravenous thrombolysis and arterial thrombectomy in our hospital in 2021, 2022 and 2023 were selected. The time tracking mode was implemented, and the patients were recorded at each time node of the hospital and the whole-process digital management was conducted. Compared the mean DNT (Door to Needle Time) of intravenous thrombolysis in emergency stroke patients in 2021, 2022 and 2023, the total number of hospital cases within 4.5 h of onset, the total number of thrombolysis cases within 4.5 h of onset, the number of intravenous thrombolysis in 60 minutes of acute ischemic stroke, and the number of thrombolysis cases. The results show that from 2021 to 2023 our emergency stroke patients with intravenous thrombolysis average DNT shortened year by year, to the hospital within 4.5 h after the onset of the difference is statistically significant (all P < 0.05) conclusion through the application of stroke time tracking platform, is beneficial to shorten the treatment time of each link, can effectively reduce the hospital time delay, improve the rate of thrombolysis, improve the reperfusion of stroke centers in primary hospitals. 展开更多
关键词 time-Tracking Platform Acute Ischemic Stroke THROMBOLYSIS THROMBECTOMY
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Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响
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作者 蔡冰红 谢晓俊 《智慧健康》 2024年第11期42-44,共3页
目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培... 目的探讨Time-lapse培养与桌面台式培养箱胚胎培养对胚胎发育的影响。方法选取2021年3月—2023年3月在本院生殖中心行IVF-ET/ICSI-ET治疗的613个周期的胚胎发育数据,随机分配胚胎培养方式。分为对照组与研究组,其中对照组为桌面台式培养箱方式(360个周期),研究组为Time-lapse培养与桌面台式培养箱方式(253个周期),统计两组胚胎发育质量。结果研究组中正常受精数、可移植胚胎数、形成囊胚数、优质胚胎数、高评分囊胚数、受精率、冷冻胚胎率、胚囊形成率、优质胚胎率、高评分囊胚率高于对照组,组间差异有统计学意义(P<0.05)。结论Time-lapse培养与桌面台式培养箱胚胎培养方式优于桌面台式培养箱方式,可为胚胎培养提供适宜的环境、温度、湿度等,有助于胚胎发育,具有较强的实用性和推广性,值得推广应用。 展开更多
关键词 time-lapse培养 桌面台式培养箱 胚胎培养 胚胎发育
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A Note on an Order Level Inventory Model with Varying Two-Phased Demand and Time-Proportional Deterioration
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作者 Sephali Mohanty Trailokyanath Singh +1 位作者 Sudhansu Sekhar Routary Chinmayee Naik 《American Journal of Operations Research》 2024年第1期59-73,共15页
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th... The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out. 展开更多
关键词 Deteriorating Items EOQ (Economic Order Quantity) INVENTORY time-Proportional Deterioration Two-Phased Demand
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Thermomechanical Dynamics (TMD) and Bifurcation-Integration Solutions in Nonlinear Differential Equations with Time-Dependent Coefficients
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第5期1733-1743,共11页
The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple ba... The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple back-and-forth motion develops into water drinking motion. The solution to a drinking bird equation of motion manifests itself the transition from thermodynamic equilibrium to nonequilibrium irreversible states. The independent solution signifying a nonequilibrium thermal state seems to be constructed as if two independent bifurcation solutions are synthesized, and so, the solution is tentatively termed as the bifurcation-integration solution. The bifurcation-integration solution expresses the transition from mechanical and thermodynamic equilibrium to a nonequilibrium irreversible state, which is explicitly shown by the nonlinear differential equation with time-dependent coefficients (NDE-TC). The analysis established a new theoretical approach to nonequilibrium irreversible states, thermomechanical dynamics (TMD). The TMD method enables one to obtain thermodynamically consistent and time-dependent progresses of thermodynamic quantities, by employing the bifurcation-integration solutions of NDE-TC. We hope that the basic properties of bifurcation-integration solutions will be studied and investigated further in mathematics, physics, chemistry and nonlinear sciences in general. 展开更多
关键词 The Nonlinear Differential Equation with time-Dependent Coefficients The Bifurcation-Integration Solution Nonequilibrium Irreversible States Thermomechanical Dynamics (TMD)
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Research on the Damping Mechanism of Time-Delay Coupled Negative Stiffness Dynamic Absorber in Nonlinear Vibration Damping System
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作者 Weikai Wang Yanying Zhao +2 位作者 Qiqi Li Hao Wu Liuqing Yang 《Open Journal of Applied Sciences》 2024年第4期818-832,共15页
A study was conducted on the effect of time delay and structural parameters on the vibration reduction of a time delayed coupled negative stiffness dynamic absorber in nonlinear vibration reduction systems. Taking dyn... A study was conducted on the effect of time delay and structural parameters on the vibration reduction of a time delayed coupled negative stiffness dynamic absorber in nonlinear vibration reduction systems. Taking dynamic absorbers with different structural and control parameters as examples, the effects of third-order nonlinear coefficients, time-delay control parameters, and negative stiffness coefficients on reducing the replication of the main system were discussed. The nonlinear dynamic absorber has a very good vibration reduction effect at the resonance point of the main system and a nearby area, and when 1 increases to a certain level, the stable region of the system continues to increase. The amplitude curve of the main system of a nonlinear dynamic absorber will generate Hop bifurcation and saddle node bifurcation in the region far from the resonance point, resulting in almost periodic motion and jumping phenomena in the system. For nonlinear dynamic absorbers with determined structural parameters, time-delay feedback control can be adopted to control the amplitude of the main system. For different negative stiffness coefficients, there exists a minimum damping point for the amplitude of the main system under the determined system structural parameters and time-delay feedback control parameters. 展开更多
关键词 Time Delay NONLINEAR Dynamic Vibration Absorber
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Gesture Recognition Based on Time-of-Flight Sensor and Residual Neural Network
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作者 Yuqian Ma Zitong Fang +4 位作者 Wen Jiang Chang Su Yuankun Zhang Junyu Wu Zhengjie Wang 《Journal of Computer and Communications》 2024年第6期103-114,共12页
With the advancement of technology and the increase in user demands, gesture recognition played a pivotal role in the field of human-computer interaction. Among various sensing devices, Time-of-Flight (ToF) sensors we... With the advancement of technology and the increase in user demands, gesture recognition played a pivotal role in the field of human-computer interaction. Among various sensing devices, Time-of-Flight (ToF) sensors were widely applied due to their low cost. This paper explored the implementation of a human hand posture recognition system using ToF sensors and residual neural networks. Firstly, this paper reviewed the typical applications of human hand recognition. Secondly, this paper designed a hand gesture recognition system using a ToF sensor VL53L5. Subsequently, data preprocessing was conducted, followed by training the constructed residual neural network. Then, the recognition results were analyzed, indicating that gesture recognition based on the residual neural network achieved an accuracy of 98.5% in a 5-class classification scenario. Finally, the paper discussed existing issues and future research directions. 展开更多
关键词 Hand Posture Recognition Human-Computer Interaction Deep Learning Gesture Datasets Real-Time Processing
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Momentum Eigensolutions of Feinberg-Horodecki Equation with Time-Dependent Screened Kratzer-Hellmann Potential 被引量:1
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作者 Mahmoud Farout Sameer M. Ikhdair 《Journal of Applied Mathematics and Physics》 2020年第7期1207-1221,共15页
We obtain an approximate value of the quantized momentum eigenvalues, <em>P<sub>n</sub></em>, together with the space-like coherent eigenvectors for the space-like counterpart of the Schr<sp... We obtain an approximate value of the quantized momentum eigenvalues, <em>P<sub>n</sub></em>, together with the space-like coherent eigenvectors for the space-like counterpart of the Schr<span style="white-space:nowrap;">&#246;</span>dinger equation, the Feinberg-Horodecki equation, with a screened Kratzer-Hellmann potential which is constructed by the temporal counterpart of the spatial form of this potential. In addition, we got exact eigenvalues of the momentum and the eigenstates by solving Feinberg-Horodecki equation with Kratzer potential. The present work is illustrated with three special cases of the screened Kratzer-Hellman potential: the time-dependent screened Kratzer potential, time-dependent Hellmann potential and, the time-dependent screened Coulomb potential. 展开更多
关键词 Coherent States Feinberg-Horodecki Equation time-Dependent Screened Kratzer-Hellmann Potential time-Dependent Kratzer Potential time-Dependent Yukawa Potential time-Dependent Hellmann Potential time-Dependent Coulomb Potential
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Time-of-Flight透散射介质成像技术综述 被引量:1
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作者 王霞 张艺馨 +1 位作者 赵雨薇 金伟其 《红外与激光工程》 EI CSCD 北大核心 2023年第2期370-381,共12页
Time-of-Flight (ToF)成像是利用光在目标和相机之间的飞行时间来获取场景的深度信息,具有体积小、成本低、实时成像等优势。在散射环境中,由于散射介质对光的散射作用,ToF成像受到多径干扰的影响,深度测量误差较大,限制了ToF相机在散... Time-of-Flight (ToF)成像是利用光在目标和相机之间的飞行时间来获取场景的深度信息,具有体积小、成本低、实时成像等优势。在散射环境中,由于散射介质对光的散射作用,ToF成像受到多径干扰的影响,深度测量误差较大,限制了ToF相机在散射场景中的应用。ToF透散射介质成像技术是校正因散射光引起的多径干扰效应,从传感器接收到的混叠信号中分离出目标分量,实现散射场景中的深度信息恢复,其在雾天自动驾驶、水下勘测、生物医学等领域具有广阔的应用前景。依据ToF成像系统的不同,详细介绍了PL-ToF和CW-ToF成像的基本原理,阐述和分析了散射场景中ToF稳态成像和瞬态成像的机理和特点,分别回顾和总结了ToF稳态成像和瞬态成像的透散射介质成像研究现状,并介绍了ToF透散射介质成像的应用前景,最后依据现有ToF透散射介质成像技术的优缺点,对未来发展趋势进行了展望。 展开更多
关键词 成像系统 透散射介质成像 time-of-Flight相机 稳态成像 瞬态成像
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Partial Time-Varying Coefficient Regression and Autoregressive Mixed Model
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作者 Hui Li Zhiqiang Cao 《Open Journal of Statistics》 2023年第4期514-533,共20页
Regression and autoregressive mixed models are classical models used to analyze the relationship between time series response variable and other covariates. The coefficients in traditional regression and autoregressiv... Regression and autoregressive mixed models are classical models used to analyze the relationship between time series response variable and other covariates. The coefficients in traditional regression and autoregressive mixed models are constants. However, for complicated data, the coefficients of covariates may change with time. In this article, we propose a kind of partial time-varying coefficient regression and autoregressive mixed model and obtain the local weighted least-square estimators of coefficient functions by the local polynomial technique. The asymptotic normality properties of estimators are derived under regularity conditions, and simulation studies are conducted to empirically examine the finite-sample performances of the proposed estimators. Finally, we use real data about Lake Shasta inflow to illustrate the application of the proposed model. 展开更多
关键词 Regression and Autoregressive Time Series Partial time-Varying Coefficient Local Polynomial
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Partial Time-Varying Coefficient Regression and Autoregressive Mixed Model
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作者 Hui Li Zhiqiang Cao 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期514-533,共20页
Regression and autoregressive mixed models are classical models used to analyze the relationship between time series response variable and other covariates. The coefficients in traditional regression and autoregressiv... Regression and autoregressive mixed models are classical models used to analyze the relationship between time series response variable and other covariates. The coefficients in traditional regression and autoregressive mixed models are constants. However, for complicated data, the coefficients of covariates may change with time. In this article, we propose a kind of partial time-varying coefficient regression and autoregressive mixed model and obtain the local weighted least-square estimators of coefficient functions by the local polynomial technique. The asymptotic normality properties of estimators are derived under regularity conditions, and simulation studies are conducted to empirically examine the finite-sample performances of the proposed estimators. Finally, we use real data about Lake Shasta inflow to illustrate the application of the proposed model. 展开更多
关键词 Regression and Autoregressive Time Series Partial time-Varying Coefficient Local Polynomial
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Blowup of Solutions to the Non-Isentropic Compressible Euler Equations with Time-Dependent Damping and Vacuum
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作者 Yuping Feng Huimin Yu Wanfang Shen 《Journal of Applied Mathematics and Physics》 2023年第7期1881-1894,共14页
This paper mainly studies the blowup phenomenon of solutions to the compressible Euler equations with general time-dependent damping for non-isentropic fluids in two and three space dimensions. When the initial data i... This paper mainly studies the blowup phenomenon of solutions to the compressible Euler equations with general time-dependent damping for non-isentropic fluids in two and three space dimensions. When the initial data is assumed to be radially symmetric and the initial density contains vacuum, we obtain that classical solution, especially the density, will blow up on finite time. The results also reveal that damping can really delay the singularity formation. 展开更多
关键词 Compressible Euler Equations BLOWUP General time-Dependent Damping VACUUM
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Extra Time Dimension: Deriving Relativistic Space-Time Transformations, Kinematics, and Example of Dimensional Compactification Using Time-Dependent Non-Relativistic Quantum Mechanics
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作者 Sajjad Zahir 《Journal of Modern Physics》 2023年第10期1333-1354,共22页
We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are d... We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are derived, leading to a new expression for the speed limit. Extending the ideas of Einstein’s Theory of Special Relativity, concepts of five-velocity and five-momenta are introduced. We get a new formula for the rest energy of a massive object. Based on a non-relativistic limit, a two-time dependent Schrödinger-like equation for infinite square-well potential is developed and solved. The extra time dimension is compactified on a closed loop topology with a period matching the Planck time. It generates interference of additional quantum states with an ultra-small period of oscillation. Some cosmological implications of the concept of four-dimensional versus five-dimensional masses are briefly discussed, too. 展开更多
关键词 Two-Time Physics Special Theory of Relativity Kaluza-Klein Theory time-Dependent Schrödinger Equation COMPACTIFICATION
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Effects of Physical Parameters and Time-Delay Coefficients on the Amplitude and Frequency Bandwidth of Saturation Controller for a Beam Vibration
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作者 Qiqi Li Yanying Zhao +1 位作者 Jiacai Zhou Weikai Wang 《Open Journal of Applied Sciences》 2023年第11期2186-2197,共12页
In this paper, the influence of physical parameters on the width of saturated control frequency band and the influence of time delay parameters on the stability of saturated control system are studied. The analytical ... In this paper, the influence of physical parameters on the width of saturated control frequency band and the influence of time delay parameters on the stability of saturated control system are studied. The analytical solution of the motion equation of the system when the main resonance and the 1:2 internal resonance occur simultaneously is obtained by multiple scale method, experimentally measured natural frequencies of nonlinear beams. The effects of excitation amplitude, delay feedback coefficients and nonlinear coefficients on saturation control are investigated. The results of the study show that the bandwidth of the saturation control can be increased by increasing the value of the external excitation, the nonlinear coefficients enhance the nonlinear phenomena of the system. 展开更多
关键词 time-DELAY Nonlinear Saturation Controller BANDWIDTH
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Parametric adaptive time-frequency representation based on time-sheared Gabor atoms 被引量:2
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作者 Ma Shiwei Zhu Xiaojin Chen Guanghua Wang Jian Cao Jialin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期1-7,共7页
A localized parametric time-sheared Gabor atom is derived by convolving a linear frequency modulated factor, modulating in frequency and translating in time to a dilated Gaussian function, which is the generalization ... A localized parametric time-sheared Gabor atom is derived by convolving a linear frequency modulated factor, modulating in frequency and translating in time to a dilated Gaussian function, which is the generalization of Gabor atom and is more delicate for matching most of the signals encountered in practice, especially for those having frequency dispersion characteristics. The time-frequency distribution of this atom concentrates in its time center and frequency center along energy curve, with the curve being oblique to a certain extent along the time axis. A novel parametric adaptive time-frequency distribution based on a set of the derived atoms is then proposed using a adaptive signal subspace decomposition method in frequency domain, which is non-negative time-frequency energy distribution and free of cross-term interference for multicomponent signals. The results of numerical simulation manifest the effectiveness of the approach in time-frequency representation and signal de-noising processing. 展开更多
关键词 time-frequency analysis Gabor atom time-shear Adaptive signal decomposition time-frequency distribution.
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Time-lapse技术联合一步法培养对胚胎发育及妊娠结局的影响 被引量:3
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作者 朱霞 邹薇 +3 位作者 李慧珍 吴卫丰 马明男 马天仲 《生殖医学杂志》 CAS 2023年第1期48-54,共7页
目的比较时差成像(Time-lapse imaging TLI)系统培养与常规低氧培养的胚胎发育情况和妊娠结局的差异。方法回顾性分析2020年12月至2022年5月在广东医科大学附属医院生殖中心接受体外受精或卵胞浆内单精子注射-胚胎移植(IVF/ICSI-ET)治... 目的比较时差成像(Time-lapse imaging TLI)系统培养与常规低氧培养的胚胎发育情况和妊娠结局的差异。方法回顾性分析2020年12月至2022年5月在广东医科大学附属医院生殖中心接受体外受精或卵胞浆内单精子注射-胚胎移植(IVF/ICSI-ET)治疗的年轻患者(20≤年龄≤35岁)的临床资料,根据胚胎培养方式分为TLI系统培养组(TLI组,n=254)和常规培养组(常规组,n=317),比较两组患者间基本资料及胚胎发育情况;再根据胚胎移植类型分为D3卵裂期胚胎移植(TLI组127例,常规组127例)和D5囊胚移植(TLI组99例,常规组143例)亚组,分别统计不同胚胎移植类型下两种培养方式的临床妊娠结局差异。结果两组患者的基本资料比较均无显著性差异(P>0.05);常规组的成熟卵母细胞率(87.2%vs.85.5%)、总受精率(77.1%vs.73.1%)、2PN卵裂数[9(6.0,13.5)vs.9(6.0,12.0)]、优胚率(38.7%vs.36.1%)均显著高于TLI组(P<0.05);两组患者间的优胚数、囊胚数、MⅡ卵母细胞数、受精总数、2PN数、卵裂总数、囊胚形成率、2PN率、2PN卵裂率、卵裂胚胎利用率的差异均无统计学意义(P>0.05)。D3卵裂期胚胎移植中,常规组的移植胚胎数显著高于TLI组[(1.80±0.11)vs.(1.68±0.47),P<0.05],两种培养方式组间胚胎着床数、种植率、HCG阳性率、临床妊娠率及双胎妊娠率均无显著性差异(P>0.05),但常规组双胎率稍高于TLI组(33.8%vs.20.3%,P>0.05);D5囊胚移植中,两种培养方式组间胚胎着床数、种植率、临床妊娠率均无显著性差异(P>0.05),但TLI组临床妊娠率稍高于常规组(65.7%vs.55.9%,P>0.05)。结论常规培养方式由于其经济、简便,是目前大多数中心的常用有效培养方法;针对年轻不孕妇女,TLI培养可能有效挑选更有种植潜力的胚胎,可能有助于提高种植率、保证妊娠率,且单胚胎移植有效减少多胎妊娠。 展开更多
关键词 时差成像 胚胎移植 多胎妊娠 妊娠结局
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Viscoacoustic prestack reverse time migration based onthe optimal time-space domain high-order finite-difference method 被引量:7
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作者 赵岩 刘洋 任志明 《Applied Geophysics》 SCIE CSCD 2014年第1期50-62,116,共14页
Prestack reverse time migration (RTM) is an accurate imaging method ofsubsurface media. The viscoacoustic prestack RTM is of practical significance because itconsiders the viscosity of the subsurface media. One of t... Prestack reverse time migration (RTM) is an accurate imaging method ofsubsurface media. The viscoacoustic prestack RTM is of practical significance because itconsiders the viscosity of the subsurface media. One of the steps of RTM is solving thewave equation and extrapolating the wave field forward and backward; therefore, solvingaccurately and efficiently the wave equation affects the imaging results and the efficiencyof RTM. In this study, we use the optimal time-space domain dispersion high-order finite-difference (FD) method to solve the viscoacoustic wave equation. Dispersion analysis andnumerical simulations show that the optimal time-space domain FD method is more accurateand suppresses the numerical dispersion. We use hybrid absorbing boundary conditions tohandle the boundary reflection. We also use source-normalized cross-correlation imagingconditions for migration and apply Laplace filtering to remove the low-frequency noise.Numerical modeling suggests that the viscoacoustic wave equation RTM has higher imagingresolution than the acoustic wave equation RTM when the viscosity of the subsurface isconsidered. In addition, for the wave field extrapolation, we use the adaptive variable-lengthFD operator to calculate the spatial derivatives and improve the computational efficiencywithout compromising the accuracy of the numerical solution. 展开更多
关键词 REVERSE time migration Viscoacoustic Optimization Adaptive time-spacedomain FINITE-DIFFERENCE
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Time-to-Count技术测量辐射强度的原理 被引量:16
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作者 刘志强 马红光 +2 位作者 马文彦 王国华 刘登和 《核电子学与探测技术》 CAS CSCD 北大核心 2006年第1期41-44,125,共5页
GM管广泛应用于辐射测量,由于传统的测量方法受到GM管死时间的影响,其测量精度不高。介绍了没有死时间影响,可以提高测量精度的T im e-to-Coun t技术的测量方法,并从理论上论证了采用该方法的数学原理,在此基础上,提出对辐射强度的新估... GM管广泛应用于辐射测量,由于传统的测量方法受到GM管死时间的影响,其测量精度不高。介绍了没有死时间影响,可以提高测量精度的T im e-to-Coun t技术的测量方法,并从理论上论证了采用该方法的数学原理,在此基础上,提出对辐射强度的新估计式,并证明该估计是无偏的渐近最优的,是形式中最优的。并通过计算机仿真证明了该方法的正确性。 展开更多
关键词 GM管 time-to-Count 原理 估计
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一种新的GM计数管Time-To-Count测量方法 被引量:14
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作者 邵晖 谈伟飞 +1 位作者 范江兵 赵家凯 《核电子学与探测技术》 CAS CSCD 北大核心 2002年第3期211-214,共4页
主要介绍了目前最新的 GM计数管 Time- To- Count测量方法的基本原理及其工作模型 ,对测量方法的基本特点进行了探讨 ,通过方案设计加以实现并给出了试验结果。
关键词 GM计数管 time-To-Count测量方法 原理 电离辐射
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Time-to-Count方法扩展GM计数管量程的实验研究 被引量:8
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作者 龚军军 邵贝贝 +1 位作者 夏文明 陈君军 《原子能科学技术》 EI CAS CSCD 北大核心 2013年第4期674-678,共5页
GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉... GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉控高压驱动、时间间隔测量等进行了讨论。在国防科技工业电离辐射一级计量站的校准试验数据表明,试验装置采用单支G1220计数管,量程可扩展至5个数量级,全量程范围线性优于10%。 展开更多
关键词 量程扩展 time-to-Count方法 脉控高压驱动 时间间隔测量
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二化螟滞育生物钟蛋白TIME-EA4基因的克隆及时空和温度诱导表达分析 被引量:9
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作者 鲁艳辉 赵燕燕 +3 位作者 张发成 郑许松 朱平阳 吕仲贤 《昆虫学报》 CAS CSCD 北大核心 2016年第4期392-401,共10页
【目的】生物测时蛋白TIME-EA4是昆虫特有的一种滞育生物钟蛋白。本文旨在克隆二化螟Chilo suppressalis TIME-EA4基因,研究其在二化螟不同发育时期和不同组织中的时空表达模式及在不同田间种群和不同温度诱导下的滞育和非滞育种群中的... 【目的】生物测时蛋白TIME-EA4是昆虫特有的一种滞育生物钟蛋白。本文旨在克隆二化螟Chilo suppressalis TIME-EA4基因,研究其在二化螟不同发育时期和不同组织中的时空表达模式及在不同田间种群和不同温度诱导下的滞育和非滞育种群中的表达水平。【方法】通过RACE技术克隆二化螟TIME-EA4基因全长c DNA序列,利用荧光定量PCR的方法检测TIME-EA4基因在二化螟不同发育时期、6龄幼虫不同组织中的表达模式,及在不同季节采集的田间种群和不同温度处理1h后的滞育和非滞育种群6龄幼虫中的表达量变化。【结果】从二化螟中克隆获得TIME-EA4的c DNA序列(Gen Bank登录号:KU356855),全长821 bp,开放阅读框516 bp,编码172个氨基酸;TIME-EA4基因在二化螟不同发育时期和不同组织中均有表达,且在早期蛹、雌雄成虫以及6龄幼虫的头部、脂肪体和中肠中表达水平较高,同时在滞育幼虫组织中的表达高于非滞育幼虫。此外,TIME-EA4基因在滞育种群中的表达量是非滞育种群的3倍左右,同时在非滞育种群中,该基因的表达明显受10℃及以下低温的诱导,且在10℃时表达量最高,而在滞育种群中该基因的表达受温度影响不明显。【结论】结果说明TIME-EA4基因与二化螟的抗低温胁迫以及低温滞育相关。本研究为TIME-EA4在农业害虫滞育的分子作用机制研究奠定了基础。 展开更多
关键词 二化螟 滞育 温度诱导 生物测时蛋白 time-EA4
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