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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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Ileal collision tumor associated with gastrointestinal bleeding: A case report and review of literature
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作者 Yu-Qi Wu Hong-Yan Wang +3 位作者 Mu-Min Shao Lin Xu Xiao-Yan Jiang Shao-Ju Guo 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期628-634,共7页
BACKGROUND Collision tumors involving the small intestine,specifically the combination of a hamartomatous tumor and a lipoma,are extremely rare.To our knowledge,no previous case report has described a collision tumor ... BACKGROUND Collision tumors involving the small intestine,specifically the combination of a hamartomatous tumor and a lipoma,are extremely rare.To our knowledge,no previous case report has described a collision tumor composed of two benign tumors of different origins in the small intestine.CASE SUMMARY Here,we present the case of an 82-year-old woman who presented with hemorrhagic shock and was found to have a mass measuring approximately 50 mm×32 mm×30 mm in the terminal ileum.Based on computed tomography scan findings,the mass was initially suspected to be a lipoma.A subsequent colonoscopy revealed a pedunculated submucosal elevation consisting of two distinct parts with a visible demarcation line.A biopsy of the upper portion suggested a juvenile polyp(JP).Owing to the patient’s advanced age,multiple comorbidities,and poor surgical tolerance,a modified endoscopic submucosal dissection was performed.Histopathological examination of the excised mucosal mass revealed a lipoma at the base and a JP at the top,demonstrating evidence of rupture and associated bleeding.The patient’s overall health remained satisfactory,with no recurrence of hematochezia during the six-month follow-up period.CONCLUSION This case report provides new evidence for the understanding of gastrointestinal collision tumors,emphasizing their diverse clinical presentations and histopathological characteristics.It also offers diagnostic and therapeutic insights as well as an approach for managing benign collision tumors. 展开更多
关键词 collision tumor Gastrointestinal bleeding Hamartomatous tumor LIPOMA modified endoscopic submucosal dissection Case report
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Localization in modified polar representation: hybrid measurements and closed-form solution
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作者 CONG Xunchao SUN Yimao +2 位作者 YANG Yanbing ZHANG Lei CHEN Liangyin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期575-588,共14页
Classical localization methods use Cartesian or Polar coordinates, which require a priori range information to determine whether to estimate position or to only find bearings. The modified polar representation (MPR) u... Classical localization methods use Cartesian or Polar coordinates, which require a priori range information to determine whether to estimate position or to only find bearings. The modified polar representation (MPR) unifies near-field and farfield models, alleviating the thresholding effect. Current localization methods in MPR based on the angle of arrival (AOA) and time difference of arrival (TDOA) measurements resort to semidefinite relaxation (SDR) and Gauss-Newton iteration, which are computationally complex and face the possible diverge problem. This paper formulates a pseudo linear equation between the measurements and the unknown MPR position,which leads to a closed-form solution for the hybrid TDOA-AOA localization problem, namely hybrid constrained optimization(HCO). HCO attains Cramér-Rao bound (CRB)-level accuracy for mild Gaussian noise. Compared with the existing closed-form solutions for the hybrid TDOA-AOA case, HCO provides comparable performance to the hybrid generalized trust region subproblem (HGTRS) solution and is better than the hybrid successive unconstrained minimization (HSUM) solution in large noise region. Its computational complexity is lower than that of HGTRS. Simulations validate the performance of HCO achieves the CRB that the maximum likelihood estimator (MLE) attains if the noise is small, but the MLE deviates from CRB earlier. 展开更多
关键词 LOCALIZATION modified polar representation time difference of arrival(TDOA) angle of arrival(AOA) closed-form solution
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Coulomb Force, Charge, and Electric Properties under Collision Space-Time
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2023年第3期686-704,共19页
We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated... We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated how to make it compatible with electric properties such as charge and the Coulomb force. The aim of this paper is to show how electric properties can be reformulated to make it consistent with collision space-time. It is shown that we need to incorporate the Planck scale into the electric constants to do so. This is also fully possible from a practical point of view, as it has recently been shown how to measure the Planck length independent of other constants and without the need for dimensional analysis. 展开更多
关键词 Coulomb’s Law Elementary Charge Planck Charge Electric Units collision Space-time
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一种估测运动目标Time-to-Collision的方法 被引量:2
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作者 李俊 张桂林 《数据采集与处理》 CSCD 1998年第3期236-240,共5页
提出了一种直接从图象序列中估测运动目标到被攻击物体的撞击时间的方法,建立了目标运动的象面模型,并设计了一种利用多子区相关跟踪器和最小二乘估计方法估测撞击时间的方案。计算机仿真实验结果证明了该方案的可行性。
关键词 计算机视觉 景象匹配 撞击时间 导弹 惯性制导
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ON COLLISION LOCAL TIME OF TWO INDEPENDENT FRACTIONAL ORNSTEIN-UHLENBECK PROCESSES 被引量:2
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作者 郭精军 李楚进 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期316-328,共13页
In this article, we study the existence of collision local time of two indepen- dent d-dimensional fractional Ornstein-Uhlenbeck processes X+^H1 and Xt^H2 with different parameters Hi ∈ (0, 1),i = 1, 2. Under the ... In this article, we study the existence of collision local time of two indepen- dent d-dimensional fractional Ornstein-Uhlenbeck processes X+^H1 and Xt^H2 with different parameters Hi ∈ (0, 1),i = 1, 2. Under the canonical framework of white noise analysis, we characterize the collision local time as a Hida distribution and obtain its' chaos expansion. Key words Collision local time; fractional Ornstein-Uhlenbeck processes; generalized white noise functionals; choas expansion 展开更多
关键词 collision local time fractional Ornstein-Uhlenbeck processes generalized white noise functionals choas expansion
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Effect of relaxation time on the squeezed correlations of bosons for evolving sources in relativistic heavy-ion collisions 被引量:1
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作者 Wei-Ning Zhang Peng-Zhi Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第2期87-92,共6页
The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the... The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the system.In this study,we investigated the effect of relaxation time on the SBBC function.We propose a method for calculating the SBBC function with relaxation-time approximation for evolving sources.SBBC functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic model.We found that the relaxation time reduces the amplitudes of the SBBC functions.This becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps. 展开更多
关键词 Relaxation time Squeezed back-to-back correlation Evolving source Relativistic heavy-ion collisions
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A modified Tikhonov regularization method for a Cauchy problem of a time fractional diffusion equation 被引量:1
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作者 CHENG Xiao-liang YUAN Le-le LIANG Ke-wei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第3期284-308,共25页
In this paper,we consider a Cauchy problem of the time fractional diffusion equation(TFDE)in x∈[0,L].This problem is ubiquitous in science and engineering applications.The illposedness of the Cauchy problem is explai... In this paper,we consider a Cauchy problem of the time fractional diffusion equation(TFDE)in x∈[0,L].This problem is ubiquitous in science and engineering applications.The illposedness of the Cauchy problem is explained by its solution in frequency domain.Furthermore,the problem is formulated into a minimization problem with a modified Tikhonov regularization method.The gradient of the regularization functional based on an adjoint problem is deduced and the standard conjugate gradient method is presented for solving the minimization problem.The error estimates for the regularized solutions are obtained under Hp norm priori bound assumptions.Finally,numerical examples illustrate the effectiveness of the proposed method. 展开更多
关键词 CAUCHY problem time-fractional diffusion equation a modified Tikhonov REGULARIZATION METHOD CONJUGATE gradient METHOD error estimates
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Particle-particle Correlation and Emission Time for ^(40)Ar+^(197)Au Collisions at 25MeV/u
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作者 He Zhiyong Duan Limin +7 位作者 Li Zuyu Jin Genming Luo Qingzheng Wu Heyu Zhang Baoguo Wen Wanxin Qi Yujin Dang Bingrong and Dai Guangxi 《IMP & HIRFL Annual Report》 1994年第0期8-9,共2页
Particle-particle Correlation and Emission Time for^(40)Ar+^(197)Au Collisions at 25MeV/u¥HeZhiyong;DuanLimin... Particle-particle Correlation and Emission Time for^(40)Ar+^(197)Au Collisions at 25MeV/u¥HeZhiyong;DuanLimin;LiZuyu;JinGenmin... 展开更多
关键词 CORRELATION AU collisionS AR EMISSION MeV PARTICLE time and at
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P-V Criticality of a Modified BTZ Black Hole in 2 + 1 Dimensional Intrinsic Time Quantum Gravity
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作者 A. S. Kubeka 《Journal of Modern Physics》 2019年第3期294-301,共8页
Intrinsic time quantum geometrodynamics is a formulation of quantum gravity naturally adapted to 3 + 1 dimensions. In this paper we construct its analogous 2 + 1 formulation, taking note of the mathematical structures... Intrinsic time quantum geometrodynamics is a formulation of quantum gravity naturally adapted to 3 + 1 dimensions. In this paper we construct its analogous 2 + 1 formulation, taking note of the mathematical structures which are preserved. We apply the resulting construction to convert the BTZ black hole metric to ITQG framework. We then modify the BTZ black hole in order to investigate the existence of the P-V criticality in ITQG theory. 展开更多
关键词 INTRINSIC time QUANTUM Geometrodynamics modified BTZ BLACK HOLE 2 + 1 QUANTUM Gravity BLACK HOLE P-V CRITICALITY Van der Waals Fluid Liquid-Gas Phase Transition
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Real Time Collision Detection Using Depth Texturing Spheres
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作者 WANG Ji~1 ZHAI Zhengjun~1 CAI Xiaobin~2 (1.College of Computer Science,Northwestern Polytechnical University,Xi’an 710072,China, 2.Committee of Science and Technology,China Aviation Industry Corporation I,Beijing 100022,China) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期1093-1096,共4页
In this paper,we present a novel collision detection algorithm to real time detect the collisions of objects.We gen- erate sphere textures of objects,and use programmable graphics hardware to mapping texture and check... In this paper,we present a novel collision detection algorithm to real time detect the collisions of objects.We gen- erate sphere textures of objects,and use programmable graphics hardware to mapping texture and check the depth of different ob- jects to detect the collision.We have implemented the algorithm and compared it with CULLIDE.The result shows that our algo- rithm is more effective than CULLIDE and has fixed executive time to suit for real-time applications. 展开更多
关键词 collision detection DEPTH texture real-time PROGRAMMABLE GRAPHICS hardware
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The Exact Solution of the Space-Time Fractional Modified Kdv-Zakharov-Kuznetsov Equation
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作者 Qiuyan Jin Tiecheng Xia Jinbo Wang 《Journal of Applied Mathematics and Physics》 2017年第4期844-852,共9页
In this paper, we get many new analytical solutions of the space-time nonlinear fractional modified KDV-Zakharov Kuznetsov (mKDV-ZK) equation by means of a new approach namely method of undetermined coefficients based... In this paper, we get many new analytical solutions of the space-time nonlinear fractional modified KDV-Zakharov Kuznetsov (mKDV-ZK) equation by means of a new approach namely method of undetermined coefficients based on a fractional complex transform. These solutions have physics meanings in natural sciences. This method can be used to other nonlinear fractional differential equations. 展开更多
关键词 Analytical Solutions the SPACE-time FRACTIONAL modified KDV-ZK EQUATION Nonlinear FRACTIONAL Differential EQUATION modified Riemann-Liouville Derivative
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Establishment of a Real-time Fluorescent Quantitative PCR Assay for Detection of Genetically Modified Maize Line MON88017
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作者 Jun SONG Dong WANG 《Agricultural Biotechnology》 CAS 2017年第1期15-19,22,共6页
In order to improve the standardized technical systems of quantitative analyses for genetically modified organisms (GMOs) and products, ensure bio-safety and reduce ecological risk in China, a real-time fluorescent ... In order to improve the standardized technical systems of quantitative analyses for genetically modified organisms (GMOs) and products, ensure bio-safety and reduce ecological risk in China, a real-time fluorescent quantitative PCR assay was established for detection of genetically modified maize line MON88017. The established method was evaluated based on the specificity, sensitivity, accuracy and measurement uncertainty. The results showed that the established method had strong specificity in detection of genetically modified maize line MON88017. 1.50% MON88017 sample was detected with 29 replica- tions. The average measured value ( 1. 541% ) was close to the actual value ( 1.50% ) and the relative deviation was 2.70%. The variation coefficient of the measured value was 0.110 g ; the recovery was 100.00% and the measurement uncertainty was 0. 096. The limit of detection for genetically modified maize line MON88017 with the established method was 5 copies at the 97.5% confidence level. Thus, the real-time fluorescent quantitative PCR assay established in this study exhibited high specificity, accuracy and sensitivity, which could provide technical support for the safety supervision of genetically modified organ- isms and products in China. 展开更多
关键词 Genetically modified maize Real-time fluorescent quantitative PCR SPECIFICITY Sensitivity ACCURACY Measurement uncertainty
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Advances in the Identification of Genetically Modified Rice with Real-time PCR and Multiplex PCR
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作者 Juan QIU 《Agricultural Biotechnology》 CAS 2017年第3期23-25,29,共4页
In recent years, food security and safety have attracted increasing attention due to the worldwide research and development of genetically modified (GM) rice, and the controversy over the commercialization of GM ric... In recent years, food security and safety have attracted increasing attention due to the worldwide research and development of genetically modified (GM) rice, and the controversy over the commercialization of GM rice. And the identification of GM rice is of great significance. Therefore, in the present study, the po- tential problems in the identification of GM rice with PCR were analyzed both at a technical level and from a theoretical perspective. In addition, PCR detection on the transgenic elements: promoter, terminator, internal reference gene and target gene was discussed, respectively. The possible solutions were proposed based on the principles of plant virology and genetic engineering. 展开更多
关键词 Genetically modified (GM) rice Qualitative detection PROMOTER TERMINATOR Bt gene Multiplex PCR Real-time PCR
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Multivariable Fuzzy Predictive Control Based on the Modified CPN Model
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作者 郑怀林 陈维南 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期108-113,共6页
Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competiti... Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competitive output manner which results in its local representation property. While studying on line, only a few parameters need to be regulated. So the model has the merits of fast learning and on line self organizing modeling. The control algorithm is simple, adaptive and useful in multivariable and time delay systems. Applying the algorithm in a paper making system, simulation shows its good effect. 展开更多
关键词 modified CPN model fuzzy predictive control MULTIVARIABLE time delay systems
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空时分数阶simplified modified Camassa-Holm方程的新精确解 被引量:1
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作者 黄春 《六盘水师范学院学报》 2020年第6期41-45,共5页
借助分数阶复变换,将分数阶偏微分方程转化为常微分方程,然后应用首次积分法,得到空时分数阶simpli⁃fied modified Camassa-Holm方程的新精确解,其中包括孤立波解、周期波解、有理函数解,丰富其精确解解系。
关键词 首次积分法 空时分数阶simplified modified Camassa-Holm方程 精确解
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Modified consecutive modal pushover procedure for seismic investigation of one-way asymmetric-plan tall buildings 被引量:4
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作者 Faramarz Khoshnoudian Mahdi Kiani 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第2期221-232,共12页
The effects of higher modes and torsion have a significant impact on the seismic responses of asymmetric-plan tall buildings. A consecutive modal pushover (CMP) procedure is one of the pushover methods that have been ... The effects of higher modes and torsion have a significant impact on the seismic responses of asymmetric-plan tall buildings. A consecutive modal pushover (CMP) procedure is one of the pushover methods that have been developed to consider these effects. The aim of this paper is to modify the (CMP) analysis procedure to estimate the seismic demands of one-way asymmetric-plan tall buildings with dual systems. An analysis of 10-, 15- and 20-story asymmetric-plan buildings is carried out, and the results from the modified consecutive modal pushover (MCMP) procedure are compared with those obtained from the modal pushover analysis (MPA) procedure and the nonlinear time history analysis (NLTHA). The MCMP estimates of the seismic demands of one-way asymmetric-plan buildings demonstrate a reasonable accuracy, compared to the results obtained from the NLTHA. Furthermore, the accuracy of the MCMP procedure in the prediction of plastic hinge rotations is better than the MPA procedure. The new pushover procedure is also more accurate than the FEMA load distribution and the MPA procedure. 展开更多
关键词 modified consecutive modal pushover seismic demands nonlinear time history analysis asymmetric-plan tall buildings TORSION
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The final collision of the CAOB:Constraint from the zircon U-Pb dating of the Linxi Formation,Inner Mongolia 被引量:22
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作者 Jie Han Jian-Bo Zhou +1 位作者 Bin Wang Jia-Lin Cao 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第2期211-225,共15页
The Linxi Formation occupies an extensive area in the eastern Inner Mongolia in the Central Asian Orogenic Belt (CAOB). The Linxi Formation is composed of slate, siltstone, sandstone and plant, lamellibranch microfo... The Linxi Formation occupies an extensive area in the eastern Inner Mongolia in the Central Asian Orogenic Belt (CAOB). The Linxi Formation is composed of slate, siltstone, sandstone and plant, lamellibranch microfossils in the associated strata. Major and trace element data (including REE) for sandstones from the formation indicate that these rocks have a greywacke protolith and have been deposited during a strong tectonic activity. LA-ICPMS U-Pb dating of detrital zircons yield ages of 1801 to 238 Ma for four samples from the Linxi Formation. 425-585 Ma, together with the ~500 Ma age for the metamorphism event previously determined for Northeast China, indicates that their provenance is the metamorphic rocks of Pan-African age that have a tectonic affinity to NE China. A few older zircons with U-Pb ages at 1689-1801 Ma, 1307 1414 Ma, 593-978 Ma are also present, revealing the Neoproterozoic history of NE China. The youngest population shows a peak at ca. 252 Ma, suggesting that the main deposition of the Linxi Formation was at late Permain. Moreover, the ca. 250 Ma zircon grains of all four samples yield weighted mean ^206pb/^238U ages of 250 ± 3 Ma, 248 ± 3 Ma, 249 ± 3 Ma, and 250 ± 2 Ma, respectively. These ages, together with the youngest zircon age in the sample ZJB-28 (ca. 238 Ma), suggest that the deposition of the Linxi Formation extended to the early Triassic. Combining with previous results, we suggest that the final collision of the Central Asian Orogenic Belt (CAOB) in the southern of Linxi Formation, which located in the Solonker-Xra Moron-Changchun suture, and the timing for final collision should be at early Triassic. 展开更多
关键词 Linxi formation LA-ICPMS U-Pb dating Solonker Xra Moron Changchun suture Final collision timing Early Triassic Central Asian Orogenic Belt
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The Calculation of Collision Risk on Air-Routes Based on Variable Nominal Separation
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作者 曲玉玲 韩松臣 《Journal of Southwest Jiaotong University(English Edition)》 2010年第4期271-277,共7页
In this paper,a new method to calculate collision risk of air-routes,based on variable nominal separation,is proposed. The collision risk model of air-routes,based on the time variable and initial time interval variab... In this paper,a new method to calculate collision risk of air-routes,based on variable nominal separation,is proposed. The collision risk model of air-routes,based on the time variable and initial time interval variable,is given. Because the distance and the collision probability vary with time when the nominal relative speed between aircraft is not zero for a fixed initial time interval,the distance,the variable nominal separation,and the collision probability at any time can be expressed as functions of time and initial time interval. By the probabilistic theory,a model for calculating collision risk is acquired based on initial time interval distribution,flow rates,and the proportion of aircraft type. From the results of calculations,the collision risk can be characterized by the model when the nominal separation changes with time. As well the roles of parameters can be shown more readily. 展开更多
关键词 collision risk model Initial time interval Variable nominal separation
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Modified Maximum Likelihood Estimation in Autoregressive Processes with Generalized Exponential Innovations
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作者 Bernardo Lagos-álvarez Guillermo Ferreira Emilio Porcu 《Open Journal of Statistics》 2014年第8期620-629,共10页
We consider a time series following a simple linear regression with first-order autoregressive errors belonging to the class of heavy-tailed distributions. The proposed model provides a useful generalization of the sy... We consider a time series following a simple linear regression with first-order autoregressive errors belonging to the class of heavy-tailed distributions. The proposed model provides a useful generalization of the symmetrical linear regression models with independent error, since the error distribution covers both correlated innovations following a Generalized Exponential distribution. Furthermore, we derive the modified maximum likelihood (MML) estimators as an efficient alternative for estimating model parameters. Finally, we investigate the asymptotic properties of the proposed estimators. Our findings are also illustrated through a simulation study. 展开更多
关键词 AUTOREGRESSIVE time Series Model MAXIMUM LIKELIHOOD modified MAXIMUM LIKELIHOOD Least SQUARES Generalized EXPONENTIAL
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