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基于测试向量中不确定位的漏电流优化技术 被引量:4
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作者 王伟 韩银和 +1 位作者 李晓维 张佑生 《电子学报》 EI CAS CSCD 北大核心 2006年第2期282-286,共5页
众所周知,CMO S电路测试时由漏电流引起的漏电流功耗在测试功耗中处于重要地位.降低测试时的漏电流对于延长需要周期性自测试的便携式系统电池寿命、提高测试的可靠性和降低测试成本都至关重要.文章首先分析了漏电流的组成,和与之相关... 众所周知,CMO S电路测试时由漏电流引起的漏电流功耗在测试功耗中处于重要地位.降低测试时的漏电流对于延长需要周期性自测试的便携式系统电池寿命、提高测试的可靠性和降低测试成本都至关重要.文章首先分析了漏电流的组成,和与之相关的晶体管的堆栈效应.然后,我们提出了一种基于测试向量中不确定位(X位)、使用遗传算法优化集成电路测试时漏电流的方法.实验结果证明在组合电路和时序电路测试中该方法能够在不影响故障覆盖率的条件下,有效优化测试时电路的漏电流. 展开更多
关键词 漏电流 不确定位 遗传算法
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Semi-analytical solution for mechanical analysis of tunnels crossing strike-slip fault zone considering nonuniform fault displacement and uncertain fault plane position
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作者 YANG Heng-hong WANG Ming-nian +1 位作者 YU Li ZHANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2116-2136,共21页
The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-e... The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-earthquake observations indicate that the displacement near the fault zone is typically nonuniform,and the fault plane position is uncertain.In this study,we first established a series of improved governing equations to analyze the mechanical response of tunnels under strike-slip fault dislocation.The proposed methodology incorporated key factors such as nonuniform fault displacement and uncertain fault plane position into the governing equations,thereby significantly enhancing the applicability range and accuracy of the model.In contrast to previous analytical models,the maximum computational error has decreased from 57.1%to 1.1%.Subsequently,we conducted a rigorous validation of the proposed methodology by undertaking a comparative analysis with a 3D finite element numerical model,and the results from both approaches exhibited a high degree of qualitative and quantitative agreement with a maximum error of 9.9%.Finally,the proposed methodology was utilized to perform a parametric analysis to explore the effects of various parameters,such as fault displacement,fault zone width,fault zone strength,the ratio of maximum fault displacement of the hanging wall to the footwall,and fault plane position,on the response of tunnels subjected to strike-slip fault dislocation.The findings indicate a progressive increase in the peak internal forces of the tunnel with the rise in fault displacement and fault zone strength.Conversely,an augmentation in fault zone width is found to contribute to a decrease in the peak internal forces.For example,for a fault zone width of 10 m,the peak values of bending moment,shear force,and axial force are approximately 46.9%,102.4%,and 28.7% higher,respectively,compared to those observed for a fault zone width of 50 m.Furthermore,the position of the peak internal forces is influenced by variations in the ratio of maximum fault displacement of the hanging wall to footwall and the fault plane location,while the peak values of shear force and axial force always align with the fault plane.The maximum peak internal forces are observed when the footwall exclusively bears the entirety of the fault displacement,corresponding to a ratio of 0:1.The peak values of bending moment,shear force,and axial force for the ratio of 0:1 amount to approximately 123.8%,148.6%,and 111.1% of those for the ratio of 0.5:0.5,respectively. 展开更多
关键词 strike-slip fault tunnel engineering semi-analytical solution fault zone width nonuniform fault displacement uncertain fault plane position
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DMM测量数据的有效位和不确定性
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作者 王绍文 《电子测试》 2002年第1期117-118,共2页
电子工程计算用的基本电学参数,几乎可用数字多用表测出.无论被测量是电压或电流,都是无限可分的量或称模拟量.而数字表显示出的结果都是数字,需要经过模/数变换和量化后显示出来.无论显示位数多少,仪表本身都有不确定性存在,它与测量... 电子工程计算用的基本电学参数,几乎可用数字多用表测出.无论被测量是电压或电流,都是无限可分的量或称模拟量.而数字表显示出的结果都是数字,需要经过模/数变换和量化后显示出来.无论显示位数多少,仪表本身都有不确定性存在,它与测量结果的准确性有重要关系. 展开更多
关键词 数字多用表 有效位 不确定位 电气测量仪表
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SoC测试中低成本、低功耗的芯核包装方法 被引量:4
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作者 王伟 韩银和 +2 位作者 胡瑜 李晓维 张佑生 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2006年第9期1397-1402,共6页
提出一种SoC测试中新颖的并行芯核包装方法(parallel core wrapper design,pCWD),该包装方法利用扫描切片重叠这一特点,通过缩短包装扫描链长度来减少测试功耗和测试时间.为了进一步减少测试时间,还提出了一种测试向量扫描切片划分和赋... 提出一种SoC测试中新颖的并行芯核包装方法(parallel core wrapper design,pCWD),该包装方法利用扫描切片重叠这一特点,通过缩短包装扫描链长度来减少测试功耗和测试时间.为了进一步减少测试时间,还提出了一种测试向量扫描切片划分和赋值算法.实验结果表明,针对ITC 2002基准SoC集中d695芯片,应用并行包装方法和测试向量切片划分及赋值算法,能够减少50%的测试时间及95%的测试功耗. 展开更多
关键词 SOC测试 芯核包装电路 不确定位 扫描切片
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基于位运算的固件代码变量区间分析法 被引量:1
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作者 谢晓东 李清宝 +2 位作者 王炜 牛小鹏 赵远 《计算机科学》 CSCD 北大核心 2013年第1期107-111,共5页
变量区间分析是程序代码数据流分析的重要部分。固件反汇编代码存在字节运算和位运算两类运算,当变量取值范围较大时,依次迭代法不能高效地分析经位运算后的结果的取值区间。提出一种快速位运算方法,即根据变量取值区间范围,先将变量转... 变量区间分析是程序代码数据流分析的重要部分。固件反汇编代码存在字节运算和位运算两类运算,当变量取值范围较大时,依次迭代法不能高效地分析经位运算后的结果的取值区间。提出一种快速位运算方法,即根据变量取值区间范围,先将变量转化为不确定位形式再进行位运算;提出一种区间生成算法,即把不确定位形式转化为区间来实现字节运算。实验结果表明,该基于位运算的固件代码变量区间分析方法在程序变量取值范围较大时效率远远高于依次迭代法,而且在各种变量取值区间范围内所需时间稳定,并随着区间范围的增大,其有略微下降趋势。 展开更多
关键词 固件代码 区间分析 不确定位 位运算
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An interacting multiple model-based two-stage Kalman filter for vehicle positioning 被引量:2
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作者 徐启敏 李旭 +1 位作者 李斌 宋向辉 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期177-181,共5页
To address the problem that a general augmented state Kalman filter or a two-stage Kalman filter cannot achieve satisfactory positioning performance when facing uncertain noise of the micro-electro-mechanical system(... To address the problem that a general augmented state Kalman filter or a two-stage Kalman filter cannot achieve satisfactory positioning performance when facing uncertain noise of the micro-electro-mechanical system(MEMS) inertial sensors, a novel interacting multiple model-based two-stage Kalman filter(IMM-TSKF) is proposed to adapt to the uncertain inertial sensor noise. Three bias filters are developed based on different noise characteristics to cover a wide range of noise levels. Then, an accurate estimation of biases is calculated by the interacting multiple model algorithm to correct the bias-free filter. Thus, the vehicle positioning system can achieve good performance when suffering from uncertain inertial sensor noise. The experimental results indicate that the average position error of the proposed IMMTSKF is 25% lower than that of the general TSKF. 展开更多
关键词 interacting multiple model(IMM) two-stage filter uncertain noise vehicle positioning
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An Efficient Test Data Compression Technique Based on Codes
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作者 方建平 郝跃 +1 位作者 刘红侠 李康 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第11期2062-2068,共7页
This paper presents a new test data compression/decompression method for SoC testing,called hybrid run length codes. The method makes a full analysis of the factors which influence test parameters:compression ratio,t... This paper presents a new test data compression/decompression method for SoC testing,called hybrid run length codes. The method makes a full analysis of the factors which influence test parameters:compression ratio,test application time, and area overhead. To improve the compression ratio, the new method is based on variable-to-variable run length codes,and a novel algorithm is proposed to reorder the test vectors and fill the unspecified bits in the pre-processing step. With a novel on-chip decoder, low test application time and low area overhead are obtained by hybrid run length codes. Finally, an experimental comparison on ISCAS 89 benchmark circuits validates the proposed method 展开更多
关键词 test data compression unspecified bits assignment system-on-a-chip test hybrid run-length codes
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Verified Solution for a Statically Determinate Truss Structure with Uncertain Node Locations 被引量:1
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作者 Andrew P. Smith Jurgen Garloff Horst Werkle 《Journal of Civil Engineering and Architecture》 2010年第11期1-10,共10页
We consider a statically determinate structural truss problem where all of the physical model parameters are uncertain: not just the material values and applied loads, but also the positions of the nodes are assumed ... We consider a statically determinate structural truss problem where all of the physical model parameters are uncertain: not just the material values and applied loads, but also the positions of the nodes are assumed to be inexact but bounded and are represented by intervals. Such uncertainty may typically arise from imprecision during the process of manufacturing or construction, or round-off errors. In this case the application of the finite element method results in a system of linear equations with numerous interval parameters which cannot be solved conventionally. Applying a suitable variable substitution, an iteration method for the solution of a parametric system of linear equations is firstly employed to obtain initial bounds on the node displacements. Thereafter, an interval tightening (pruning) technique is applied, firstly on the element forces and secondly on the node displacements, in order to obtain tight guaranteed enclosures for the interval solutions for the forces and displacements. 展开更多
关键词 Truss systems finite element method uncertain parameters interval arithmetic.
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Clearance Effects in Parallel Manipulators: Position Error Discontinuities and Inertial Effects Influence 被引量:1
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作者 Oscar Altuzarra Jokin Aginaga +1 位作者 Charles Pinto Xabier Iriarte 《Journal of Mechanics Engineering and Automation》 2012年第1期41-51,共11页
Clearances at joints cause an uncertainty in the actual posture of the end-effector of any mechanism. This uncertainty relays on the clearance dimension and the way these clearances are taken up by the mechanism under... Clearances at joints cause an uncertainty in the actual posture of the end-effector of any mechanism. This uncertainty relays on the clearance dimension and the way these clearances are taken up by the mechanism under the load and the inertial effects at every instant. As a matter of fact, the actual measure of the pose error is often replaced by an uncertainty measure. However, a side effect of the existence of clearances is that they can cause sudden changes in the posture of the mechanism as a motion is performed. Such discontinuities in the position produce task defects and impacts. In this work a tool to determine the pose error due to clearances is presented together with a discontinuity analysis. In addition, effects of mass distribution and inertial effects on such discontinuities are expounded, taking a 3-PRS robot as example. 展开更多
关键词 Parallel manipulator CLEARANCE position error discontinuity.
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Effects of Uncertainties in the Position and Orientation of Both the Transmitter and Receivers on Marine Controlled-Source Electromagnetic Data 被引量:3
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作者 XU Zhenhuan LIU Ying LI Yuguo 《Journal of Ocean University of China》 SCIE CAS 2016年第1期83-92,共10页
Simulation and interpretation of marine controlled-source electromagnetic(CSEM) data often approximate the transmitter source as an ideal horizontal electric dipole(HED) and assume that the receivers are located on a ... Simulation and interpretation of marine controlled-source electromagnetic(CSEM) data often approximate the transmitter source as an ideal horizontal electric dipole(HED) and assume that the receivers are located on a flat seabed.Actually,however,the transmitter dipole source will be rotated,tilted and deviated from the survey profile due to ocean currents.And free-fall receivers may be also rotated to some arbitrary horizontal orientation and located on sloping seafloor.In this paper,we investigate the effects of uncertainties in the transmitter tilt,transmitter rotation and transmitter deviation from the survey profile as well as in the receiver's location and orientation on marine CSEM data.The model study shows that the uncertainties of all position and orientation parameters of both the transmitter and receivers can propagate into observed data uncertainties,but to a different extent.In interpreting marine data,field data uncertainties caused by the position and orientation uncertainties of both the transmitter and receivers need to be taken into account. 展开更多
关键词 electromagnetic uncertainty in position and orientations data certainty marine CSEM
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Effect of Uncertainty of Grid DEM on TOPMODEL:Evaluation and Analysis 被引量:1
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作者 WANG Peifa DU Jinkang +1 位作者 FENG Xuezhi KANG Guoding 《Chinese Geographical Science》 SCIE CSCD 2006年第4期320-326,共7页
TOPMODEL,a semi-distributed hydrological model,has been widely used.In the process of simulation of the model,Digital Elevation Model(DEM) is used to provide the input data,such as topographic index and distance to th... TOPMODEL,a semi-distributed hydrological model,has been widely used.In the process of simulation of the model,Digital Elevation Model(DEM) is used to provide the input data,such as topographic index and distance to the drainage outlet;thus DEM plays an important role in TOPMODEL.This study aims at examining the impacts of DEM uncertainty on the simulation results of TOPMODEL.In this paper,the effects were evaluated mainly from quantitative and qualitative aspects.Firstly,DEM uncertainty was simulated by using the Monte Carlo method,and for every DEM realization,the topographic index and distance to the drainage outlet were extracted.Secondly,the obtained topographic index and the distance to the drainage outlet were input to the TOPMODEL to simulate seven rain-storm-flood events,and four evaluation indices,such as Nash and Sutcliffe efficiency criterion(EFF),sum of squared residuals over all time steps(SSE),sum of squared log residuals over all time steps(SLE) and sum of absolute errors over all time steps(SAE) were recorded.Thirdly,these four evaluation indices were analyzed in statistical manner(minimum,maximum,range,standard deviation and mean value),and effect of DEM uncertainty on TOPMODEL was quantitatively analyzed.Finally,the simulated hydrographs from TOPMODEL using the original DEM and realizations of DEM were qualitatively evaluated under each flood cases.Results show that the effect of DEM uncertainty on TOPMODEL is inconsiderable and could be ignored in the model’s application.This can be explained by:1) TOPMODEL is not sensitive to the distribution of topographic index and distance to the drainage outlet;2) the distri-bution of topographic index and distance to the drainage outlet are slightly affected by DEM uncertainty. 展开更多
关键词 DEM uncertainty TOPMODEL Monte Carlo simulation Jiaokou watershed
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Reducing Uncertainty in Subdivision Optimization 被引量:1
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作者 Romanas Puisa Nikolaos Tsakalakis Dracos Vassalos 《Journal of Shipping and Ocean Engineering》 2012年第1期18-27,共10页
Design of watertight subdivision inherently involves its optimization with the objective to increase the index "A" above its minimum required value. In view of a big popularity of probabilistic search methods such a... Design of watertight subdivision inherently involves its optimization with the objective to increase the index "A" above its minimum required value. In view of a big popularity of probabilistic search methods such as genetic algorithms, this task is intrinsically time consuming. Thus, even when an optimal subdivision layout (i.e. topology) is determined, it can be found that the optimal bulkhead positions can be a great challenge time-wise, often forcing designers to satisfy with suboptimal solutions. The fundamental reason why this happens is that the nature of the optimized function (e.g., index "A" as a function of bulkhead positions) is unknown and hence it has no effect upon the choice of optimization strategy, which therefore reflects subjective but not factual preferences. In this paper we study the nature of functional dependency between the subdivision index and bulkhead positions, as a simplest case, and indicate pertinent optimization strategies that consequently reduce the optimization time. In our study we use a cruise ship model to demonstrate the application results of our findings. 展开更多
关键词 Damage stability OPTIMIZATION watertight subdivision index "A" logistic regression cruise ship APPROXIMATION surrogate function.
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Improving performance of open-pit mine production scheduling problem under grade uncertainty by hybrid algorithms
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作者 Kamyar TOLOUEI Ehsan MOOSAVI +2 位作者 Amir Hossein BANGIAN TABRIZI Peyman AFZAL Abbas AGHAJANI BAZZAZI 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2479-2493,共15页
One of the surface mining methods is open-pit mining,by which a pit is dug to extract ore or waste downwards from the earth’s surface.In the mining industry,one of the most significant difficulties is long-term produ... One of the surface mining methods is open-pit mining,by which a pit is dug to extract ore or waste downwards from the earth’s surface.In the mining industry,one of the most significant difficulties is long-term production scheduling(LTPS)of the open-pit mines.Deterministic and uncertainty-based approaches are identified as the main strategies,which have been widely used to cope with this problem.Within the last few years,many researchers have highly considered a new computational type,which is less costly,i.e.,meta-heuristic methods,so as to solve the mine design and production scheduling problem.Although the optimality of the final solution cannot be guaranteed,they are able to produce sufficiently good solutions with relatively less computational costs.In the present paper,two hybrid models between augmented Lagrangian relaxation(ALR)and a particle swarm optimization(PSO)and ALR and bat algorithm(BA)are suggested so that the LTPS problem is solved under the condition of grade uncertainty.It is suggested to carry out the ALR method on the LTPS problem to improve its performance and accelerate the convergence.Moreover,the Lagrangian coefficients are updated by using PSO and BA.The presented models have been compared with the outcomes of the ALR-genetic algorithm,the ALR-traditional sub-gradient method,and the conventional method without using the Lagrangian approach.The results indicated that the ALR is considered a more efficient approach which can solve a large-scale problem and make a valid solution.Hence,it is more effectual than the conventional method.Furthermore,the time and cost of computation are diminished by the proposed hybrid strategies.The CPU time using the ALR-BA method is about 7.4%higher than the ALR-PSO approach. 展开更多
关键词 open-pit mine long-term production scheduling grade uncertainty augmented Lagrangian relaxation particle swarm optimization algorithm bat algorithm
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A Breakthrough of Primary Structure in Indeterminate Analysi--Irregular Force Method and Irregular Displacement Method
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作者 Ren Song 《Journal of Civil Engineering and Architecture》 2010年第12期47-55,共9页
As the strict limitation of primary structure in traditional force method and displacement method in indeterminate analysis may lead to complicated high-order linear equations, a breakthrough of the limitation, i.e., ... As the strict limitation of primary structure in traditional force method and displacement method in indeterminate analysis may lead to complicated high-order linear equations, a breakthrough of the limitation, i.e., the application of irregular force method and irregular displacement method, would be introduced in this paper to ease the difficulty of hand computations. By using hyperstatic primary structures and partly chained primary structures, the primary structures of force method and displacement method are reformed, and the order of the system is decreased. The technique is explained through examples. The significance of the new method is summarized. 展开更多
关键词 assistant diagram irregular force method hyperstatic primary structure irregular displacement method partly chained primary structure.
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Dynamic Friction Control Using Dynamic Structured RFNN and Friction Parameter Estimator
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作者 Seong-ik HAN Kwon-soon LEE +2 位作者 Dae-yeon YEO Sang-ok HAN Kyung-wan KOO 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期191-194,共4页
A nonlinear dynamic friction control is dealt with using dynamic friction observer and intelligent cantrol. The adaptive dynamic friction obsrver based on the LuGre friction is proposed to estimate the friction parame... A nonlinear dynamic friction control is dealt with using dynamic friction observer and intelligent cantrol. The adaptive dynamic friction obsrver based on the LuGre friction is proposed to estimate the friction parameters and a directly friction state variable The dynamic structured Fuzzy Neural Network (RFNN) is designed to give additional robustness to the cantrol system under the presence of the friction model uncertainty. A proposed composite cantrol scheme is applied to the position tracking control of the servo systen. The performances of the proposed friction observer and the friction controller are demonstrated by simulation. 展开更多
关键词 LuGre friction model adaptive friction observer dynamic structured RFNN servo system control
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Effect of the span of Australian GPS coordinate time series in establishing an optimal noise model 被引量:10
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作者 JIANG WeiPing ZHOU XiaoHui 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第4期523-539,共17页
The span of coordinate time series affects the determination of an optimal noise model. We analyzed position data recorded for 10 continuous Global Positioning System (GPS) sites from 1998.0 to mid-2009 on the Austr... The span of coordinate time series affects the determination of an optimal noise model. We analyzed position data recorded for 10 continuous Global Positioning System (GPS) sites from 1998.0 to mid-2009 on the Australian Plate to estimate the best noise model and thereafter obtain the true uncertainties of the velocity, employing the maximum likelihood estimation (MLE) method. MLE was employed to analyze the data in four ways. In the first two analyses, the noise was assumed to be a combination of flicker noise and white noise for the raw time series and spatially filtered time series. In the final two analyses, the spectral indices and amplitudes were simultaneously estimated for a power law noise plus white noise model for the raw time series and spatially filtered time series. We conclude that the noise model of GPS time series in Australia can be best described as the combination of flicker noise and white noise. Velocity uncertainties fall below -0.2 mm/yr when the time span exceeds -9.5 years. A comparison of noise amplitudes and maximum likelihood estimation values between the raw and spatially filtered time series suggests that traditional spatial filtering to remove common-mode errors might not be applicable to the raw time series of this region. 展开更多
关键词 Australian Plate Global Positioning System time series noise model maximum likelihood estimation
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Constructing confidence intervals of extreme rainfall quantiles using Bayesian,bootstrap,and profile likelihood approaches 被引量:4
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作者 CHEN Si LI YaXing +1 位作者 SHIN JiYae KIM TaeWoong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第4期573-585,共13页
Hydrological risk is highly dependent on the occurrence of extreme rainfalls.This fact has led to a wide range of studies on the estimation and uncertainty analysis of the extremes.In most cases,confidence intervals(C... Hydrological risk is highly dependent on the occurrence of extreme rainfalls.This fact has led to a wide range of studies on the estimation and uncertainty analysis of the extremes.In most cases,confidence intervals(CIs)are constructed to represent the uncertainty of the estimates.Since the accuracy of CIs depends on the asymptotic normality of the data and is questionable with limited observations in practice,a Bayesian highest posterior density(HPD)interval,bootstrap percentile interval,and profile likelihood(PL)interval have been introduced to analyze the uncertainty that does not depend on the normality assumption.However,comparison studies to investigate their performances in terms of the accuracy and uncertainty of the estimates are scarce.In addition,the strengths,weakness,and conditions necessary for performing each method also must be investigated.Accordingly,in this study,test experiments with simulations from varying parent distributions and different sample sizes were conducted.Then,applications to the annual maximum rainfall(AMR)time series data in South Korea were performed.Five districts with 38-year(1973–2010)AMR observations were fitted by the three aforementioned methods in the application.From both the experimental and application results,the Bayesian method is found to provide the lowest uncertainty of the design level while the PL estimates generally have the highest accuracy but also the largest uncertainty.The bootstrap estimates are usually inferior to the other two methods,but can perform adequately when the distribution model is not heavy-tailed and the sample size is large.The distribution tail behavior and the sample size are clearly found to affect the estimation accuracy and uncertainty.This study presents a comparative result,which can help researchers make decisions in the context of assessing extreme rainfall uncertainties. 展开更多
关键词 BAYESIAN BOOTSTRAP profile likelihood confidence interval frequency analysis
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Isotope effect of the phonons mean free path in graphene by micro-Raman measurement 被引量:1
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作者 ZHANG CanKun LI QiongYu +6 位作者 TIAN Bo HUANG ZhiYi LIN WeiYi LI HongYang HE DaHai ZHOU YingHui CAI WeiWei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第10期1817-1821,共5页
The isotope labeled graphene was synthesized in the concentration of 13 C carbon atom in 1%, 25%, 50%, 75% and 99%. The isotope effect on the phonon behavior in graphene was investigated based on the micro-Raman analy... The isotope labeled graphene was synthesized in the concentration of 13 C carbon atom in 1%, 25%, 50%, 75% and 99%. The isotope effect on the phonon behavior in graphene was investigated based on the micro-Raman analysis of 13 C isotope labeled graphene samples. We found that the phonon scattering is affected by the isotopic carbon atom as a point defect. Based on the experiment results, the Klemens-Callaway model and uncertainty principle were used to obtain the mean free path of the G and D phonons. The results agree with the thermal conductivity measurement by non-contact optical method and with other theoretical calculations. 展开更多
关键词 GRAPHENE isotope effect PHONON mean free path
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Uncertainty and Certainty Relations for Successive Projective Measurements of a Qubit in Terms of Tsallis' Entropies
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作者 Alexey E.Rastegin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第6期687-694,共8页
We study uncertainty and certainty relations for two successive measurements of two-dimensional observables. Uncertainties in successive measurement are considered within the following two scenarios. In the first scen... We study uncertainty and certainty relations for two successive measurements of two-dimensional observables. Uncertainties in successive measurement are considered within the following two scenarios. In the first scenario, the second measurement is performed on the quantum state generated affer the first measurement with completely erased information. In the second scenario, the second measurement is performed on the post-first- tioned on the actual measurement outcome. Induced entropies. For two successive projective t state condiquantum uncertainties are characterized by means of the Tsallis t of a qubit, we obtain minimal and maximal values of related entropic measures of induced uncertainties. Some conclusions found in the second scenario are extended to arbitrary finite dimensionality. In particular, a connection with mutual unbiasedness is emphasized. 展开更多
关键词 successive measurements Tsallis entropy uncertainty principle PURITY
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