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Best Linear Unbiased Estimators of Location and Scale Ranked Set Parameters under Moving Extremes Sampling Design

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 222-231页

作者： Yan-fei DONG wang-xue chen Min-yu XIE Department of Mathematics and Statistics Jishou UniversityJishou 416000China Department of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

In the current paper,the best linear unbiased estimators(BLUEs)of location and scale parameters from location-scale family will be respectively proposed in cases when one parameter is known and when both are unknown under moving extremes ranked set sampling(MERSS).Explicit mathematical expressions of these estimators and their variances are *** relative efficiencies with respect to the minimum variance unbiased estimators(MVUEs)under simple random sampling(SRS)are compared for the cases of some usual *** numerical results show that the BLUEs under MERSS are significantly more efficient than the MVUEs under SRS.

关键词： location-scale parameters best linear unbiased estimator moving extremes ranked set sampling

Maximum Likelihood Estimator of the Location Parameter under Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 101-108页

作者： wang-xue chen Chun-xian LONG Rui YANG Dong-sen YAO Department of Mathematics and Statistics Jishou UniversityJishou 416000China

Cost effective sampling design is a problem of major concern in some experiments especially when the measurement of the characteristic of interest is costly or painful or time *** the current paper,a modification of ranked set sampling(RSS)called moving extremes RSS(MERSS)is considered for the estimation of the location parameter for location family.A maximum likelihood estimator(MLE)of the location parameter for this family is studied and its properties are *** prove that the MLE is an equivariant estimator under location *** order to give more insight into the performance of MERSS with respect to(w.r.t.)simple random sampling(SRS),the asymptotic efficiency of the MLE using MERSS *** using SRS is computed for some usual location *** relative results show that the MLE using MERSS can be real competitors to the MLE using SRS.

关键词： ranked set sampling moving extremes ranked set sampling maximum Likelihood estimator equivariant estimator fisher information number

Exponential-Poisson Parameters Estimation in Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年

作者： Meng chen wang-xue chen Rui YANG Ya-wen ZHOU Department of Mathematics and Statistics Jishou University

In this article, the maximum likelihood estimators (MLEs) of the scale and shape parameters βandλfrom the Exponential-Poisson distribution will be considered in moving extremes ranked set sampling(MERSS). These MLEs will be compared in terms of asymptotic efficiencies. The numerical results show that these MLEs in MERSS can be real competitors against those in simple random sampling.

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Synthesis and characterization of arsenate antimonic acid AAAc(1 : 1)

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Journal of Central South University of Technology 2005年第z1期12卷 76-81页

作者： wang xue-wen chen Qi-yuan YIN Zhou-lan ZHANG Ping-min wang Yu-wen School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Central South University Changsha 410083 China Chemistry Department Jinggangshan Normal College Ji''an 343009 China

The AAAc(1 : 1) was synthesized in water by As2O3 and Sb2O3 with molar ratio of 1 : 1: AAAc(1 : 1)was characterized by Raman, IR, TG/DTG, DSC, XPS and XRD. The results show that there are four peaks to vsof As-OH, As-O-Sb, Sb-OH and Sb-O-Sb in Raman spectra of AAAc(1 : 1) at 100 - 1 000 cm-1. The solution of AAAc(1 : 1) was also titrated with KOH solution. The titration results show that AAAc(1 : 1) is a hexabasic acid with dissociation constants of k1 = 3.62 × 10-2 , k2 = 3.05 × 10-3 , k3 = 6. 43 × 10-6 , k4 = 9. 78 × 10-8 ,k5 = 1.32 × 10-11 , k6 =3.87 × 10-12. AAAc(1 : 1) has a good solubility and stability in water, its solid obtained by free volatilizing water from its solution under air at ambient temperature is amorphous. Chemical and thermal analyture of AsO ( OH )2-OH-Sb ( OH )4-O-Sb ( OH )4-OH-AsO ( OH )2 or As ( OH )3-O-Sb(OH)4-O-Sb(OH)4-O-As(OH)3 (isomerism) through experimental determination and geometry optimization.

关键词： arsenic acid antimonic acid arsenate antimonic acid

Betaine accumulation and the change of betaine-aldehyde dehydrogenase activity in barley seedlings under KCl and NaCl stress

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Journal of Environmental Sciences 1999年第4期11卷 415-418,442页

作者： YI Yan-jun XU cheng-shui ZHAO Bo-sheng LIU Jia-yao wang xue-chen Department of Biology Qufu Normal UniversityQufu 273165China Department of Biology Zibo CollegeZibo 255013China College of Biology Chinese Agricultural Universi tyBeijing 100094China

The changes in growth status, ion contents, betaine levels and betaine\|aldehyde dehydrogenase (BADH) activity in seedlings of nonhalophyte barley treated with different concentrations of NaCl and KCl were studied. Results showed that the inhibition of growth in barley seedlings increased as enhancing NaCl and KCl for 96h and NaCl inhibitory degree was higher than that of KCl. The K\++ content of barley seedlings in NaCl was lower than the control, while the Na\++ content was higher, the levels of Na\++ fell in the seedlings treated with KCl, but K\++ levels rose, and K\++ content was higher than that of Na\++. The betaine levels of barley shoots rose with the increase in both external salt concentration and treatment time. Higher BADH activity was observed in low\|salt concentration but lower slightly in high\|salt concentration.

关键词： betaine betaine-aldehyde dehydrogenase(BADH) activity NaCl KCl barley

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解决约束平面偏移问题的机械臂闭环标定

浙江大学学报（工学版） 2018年第11期52卷 2110-2119页

作者：王晨学平雪良徐超江南大学机械工程学院江苏省食品先进制造装备技术重点实验室江苏无锡214122

基于平面约束的工业机械臂闭环标定,拟合平面与实际约束平面之间存在一定偏差,直接影响标定精度.针对此问题提出消除偏差的方法及误差模型.建立平面坐标系,得到约束平面的准确方程,通过接触式测量头对约束平面进行测量,在平面坐标系中... 详细信息

基于平面约束的工业机械臂闭环标定,拟合平面与实际约束平面之间存在一定偏差,直接影响标定精度.针对此问题提出消除偏差的方法及误差模型.建立平面坐标系,得到约束平面的准确方程,通过接触式测量头对约束平面进行测量,在平面坐标系中描述测量点的位置;建立最小完整连续运动学模型,从而减少冗余参数的影响;利用双目视觉定位约束平面并规划理论测量点位置,实现自动化测量;通过改进的最小二乘法对参数误差进行辨识.实验结果表明,修正运动学参数后,机械臂绝对位置精度由1.234 mm提高到0.405 mm.该方法成本低、精度高、效率高,且简化了误差模型,适用于工业机械臂的现场标定,为机械臂生产厂家实现批量化标定及后期设备维护提供了思路.

关键词：工业机械臂平面约束平面偏移闭环标定双目视觉

A General Method for QTL Mapping in Multiple Related Populations Derived from Multiple Parents

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Rice science 2009年第1期16卷 45-50页

作者： AO Yan HU Zhi-qiu TANG Zai-xiang wang xue-feng XU chen-wu Jiangsu Provincial Key Laboratory of Crop Genetics ＆ Physiology Yangzhou University Yangzhou 225009 China

It＇s well known that incorporating some existing populations derived from multiple parents may improve QTL mapping and QTL-based breeding programs. However, no general maximum likelihood method has been available for this strategy. Based on the QTL mapping in multiple related populations derived from two parents, a maximum likelihood estimation method was proposed, which can incorporate several populations derived from three or more parents and also can be used to handle different mating designs. Taking a circle design as an example, we conducted simulation studies to study the effect of QTL heritability and sample size upon the proposed method. The results showed that under the same heritability, enhanced power of QTL detection and more precise and accurate estimation of parameters could be obtained when three F2 populations were jointly analyzed, compared with the joint analysis of any two F2 populations. Higher heritability, especially with larger sample sizes, would increase the ability of QTL detection and improve the estimation of parameters. Potential advantages of the method are as follows： firstly, the existing results of QTL mapping in single population can be compared and integrated with each other with the proposed method, therefore the ability of QTL detection and precision of QTL mapping can be improved. Secondly, owing to multiple alleles in multiple parents, the method can exploit gene resource more adequately, which will lay an important genetic groundwork for plant improvement.

关键词： related population quantitative trait locus gene mapping maximum likelihood estimation

Existence and Characteristics of Tonoplast-bound Protein Kinase in the Tip Cell of Maize Root

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Acta Botanica Sinica 2002年第6期44卷 661-666页

作者：陈硕陈珈王学臣中国农业大学生物学院

For understanding the function of tonoplast protein in plant cell signal pathway, we have identified an integral protein kinase activity from the highly purified tonoplast isolated from maize ( Zea mays L.) root by a new nonradioactive method in which a color labeled peptide was used as substrate. The protein kinase was Ca 2+ _dependent and CaM and phosphatidylserine_independent, like the calmodulin_like domain protein kinase (CDPK) in many plants. The optimal pH value and Ca 2+ concentration were 6.5 and 10 μmol/L, respectively. According to the optimal pH value and the effect of detergent, it could be inferred that the active site of this protein kinase is oriented toward the cytoplasm. Zn 2+ had no obvious effect on its activity, indicating that this protein kinase has no zinc_finger domain that exists in some mammalian protein kinases. At the same time, when tonoplast proteins were prephosphorylated in the presence of Ca 2+ and ATP, both the ATP_hydrolysis and the proton_transport activity of vacuolar H +_ATPase were stimulated. This stimulation could be reversed by an alkaline_phosphatase. These results indicate that a Ca 2+ _dependent protein kinase was located in the tonoplast, and a Ca 2+ _dependent phosphorylation, probably caused by this kinase, activated the vacuolar H +_ATPase activity. These results are helpful for further research on the function of CDPK in the course of signal transduction in plants.

关键词： protein kinase phosphorylation H +_ATPase tonoplast maize

Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-Lin Xiong Ji-Rong Mao Shuang-Nan Zhang wang-chen xue Chao Zheng Jia-Cong Liu Zhen Zhang Xi-Lu wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai Xin-Qiao Li Wen-Xi Peng Wen-Jun Tan chen-Wei wang Xiang-Yang Wen Yue wang Shuo Xiao Fan Zhang Peng Zhang Shi-Jie Zheng Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line