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| 1 | Temporal-spatial subspaces modern combination method for 2D-DOA estimation in MIMO radar显示文摘A 2D-direction of arrival estimation(DOAE) for multiinput and multi-output(MIMO) radar using improved multiple temporal-spatial subspaces in estimating signal parameters via rotational invariance techniques method(TS-ESPRIT) is introduced. In order to realize the improved TS-ESPRIT, the proposed algorithm divides the planar array into multiple uniform sub-planar arrays with common reference point to get a unified phase shifts measurement point for all sub-arrays. The TS-ESPRIT is applied to each sub-array separately, and in the same time with the others to realize the parallelly temporal and spatial processing, so that it reduces the non-linearity effect of model and decreases the computational time. Then, the time difference of arrival(TDOA)technique is applied to combine the multiple sub-arrays in order to form the improved TS-ESPRIT. It is found that the proposed method achieves high accuracy at a low signal to noise ratio(SNR)with low computational complexity, leading to enhancement of the estimators performance. | Youssef Fayad Caiyun Wang Qunsheng Cao | 2017 | Journal of Systems Engineering and Electronics2017，28，4： | 7 |
| 2 | ADMISSIBILITY OF LINEAR ESTIMATES OF REGRESSION COEFFICIENT UNDER MATRIX LOSS FUNCTION显示文摘We consider the linear model (1) where V>0 and X are known, n≥p; β∈R^p, and 0<σ~2<∞ are unknown. Consider the problem of estimating Sβ which is linear estimable. Prof. C. R. Rao has given the necessary and sufficient condition that LY is admissible for Sβ within | 吴启光 | 1983 | Chinese Science Bulletin1983，28，2： | 6 |
| 3 | A general additive-multiplicative rates model for recurrent event data显示文摘In this article, we propose a general additive-multiplicative rates model for recurrent event data. The proposed model includes the additive rates and multiplicative rates models as special cases. For the inference on the model parameters, estimating equation approaches are developed, and asymptotic properties of the proposed estimators are established through modern empirical process theory. In addition, an illustration with multiple-infection data from a clinic study on chronic granulomatous disease is provided. | DAI JiaJia SUN LiuQuan YANG ZhenHai | 2009 | Science China Mathematics2009，52，10： | 5 |
| 4 | DISCUSSION ON THEORY OF DETERMINATION OF AQUIFER PARAMETERS FROM WELL TIDES显示文摘The theory of estimating the aquifer parameters by using the tidal water level data in the well in conjunction with barometric data in situ has been presented in Ref. [1] and then developed in Refs. [2] and (3)However, it was negated in principle in Ref. (4)In this article the subject will be discussed and the derived formulas compared with the relative formulas already mentioned. | 杜品仁 | 1988 | Chinese Science Bulletin1988，33，8： | 4 |
| 5 | CONSISTENT NONPARAMETRIC ESTIMATION OF ERROR DISTRIBUTIONS IN LINEAR MODEL'显示文摘For the linear model y_i=x_iθ+e_i, i=1, 2,…, let the error sequence {e_i}_i=1 be iidr.v.’s, with unknown density f(x). In this paper,a nonparametric estimation method based onthe residuals is proposed for estimating f(x) and the consistency of the estimators is obtained. | 柴根象 李竹渝 田红 | 1991 | Acta Mathematicae Applicatae Sinica1991，7，3： | 4 |
| 6 | Risk and size estimation of debris flow caused by storm rainfall in mountain regions显示文摘Debris flow is a common disaster in mountain regions. The valley slope, storm rainfall and amassed sand-rock materials in a watershed may influence the types of debris flow. The bursting of debris flow is not a pure random event. Field investigations show the periodicity of its burst, but no directive evidence has been found yet. A risk definition of debris flow is proposed here based upon the accumulation and the starting conditions of loose material in channel. According to this definition, the risk of debris flow is of quasi-periodicity. A formula of risk estimation is derived. Analysis of relative factors reveals the relationship between frequency and size of debris flow. For a debris flow creek, the longer the time interval between two occurrences of debris flows is, the bigger the bursting event will be. | CHENG Genwei Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China | 2003 | Science China(Technological Sciences)2003，46，z1： | 3 |
| 7 | NEW GROUP-CONTRIBUTION CORRELATIONS FOR ESTIMATION OF CRITICAL PROPERTIES显示文摘New correlations based on group-contribution method for estimating critical properties have been proposed with con-tribution values of 67 groups.The new correlations have been examined by extensive comparison of the values calculatedwith the experimental data of 275 substanees.The average percent deviations of estimation of T_c,P_c and V_c are respective-ly 0.76,2.73 and 2.50 which are lower than those estimated by the Lydersen method and the Ambrose method chosenfor eomparision. | 马沛生 徐明 许文 张建侯 | 1990 | Chinese Journal of Chemical Engineering1990，，2： | 3 |
| 8 | Local asymptotic behavior of regression splines for marginal semiparametric models with longitudinal data显示文摘In this paper, we study the local asymptotic behavior of the regression spline estimator in the framework of marginal semiparametric model. Similarly to Zhu, Fung and He (2008), we give explicit expression for the asymptotic bias of regression spline estimator for nonparametric function f. Our results also show that the asymptotic bias of the regression spline estimator does not depend on the working covariance matrix, which distinguishes the regression splines from the smoothing splines and the seemingly unrelated kernel. To understand the local bias result of the regression spline estimator, we show that the regression spline estimator can be obtained iteratively by applying the standard weighted least squares regression spline estimator to pseudo-observations. At each iteration, the bias of the estimator is unchanged and only the variance is updated. | QIN GuoYou ZHU ZhongYi | 2009 | Science China Mathematics2009，52，9： | 2 |
| 9 | Beamforming of random line array显示文摘In order to solve the problem of the sensor location uncertaintyfor a towed line array,the sample matrix of the signal and time-spacecurve equations of the simulated array shape are presented in this paper.Average beampatterns of randomized processing are given too.The quan-titative results of array shape variation and distortion losses are obtainedfrom the comparison between the computer simulation and the experimen-tal results.In addition,a model for estimating array shape is offered.Anexperiment on dynamical beamforming is carried out.The results showthat SNR improvement of about 4dB may be obtained by dynamic com-pensation for a small array when the distortion is medial and the towspeed is low. | SHAN Bingyi(Hangzhou Applied Acoustics Institute Hangzhou 311400) | 1992 | Chinese Journal of Acoustics1992，11，2： | 2 |
| 10 | Predictive value of neutrophil-to-lymphocyte ratio and other inflammatory indicators in estimating clinical severity of coronavirus disease显示文摘Dear editor,The recent outbreak of coronavirus disease(COVID-19)has become a major public health issue caused by 2019 novel coronavirus(2019-nCoV).[1]Severe COVID-19 patients may reveal a dysregulated immune response that allows the development of v iral hyperinfl ammation.[2]In the fight against COVID-19,inflammatory parameters towards illness severity should be identified to improve the prognosis of patients.In this study,we aimed to assess the discriminative ability of several infl ammation indicators in severe COVID-19 infection. | Guang-qing Yu Qing Zhang Run-chang Wang Shi-qin Jiang | 2021 | World Journal of Emergency Medicine2021，12，1： | 2 |
| 11 | Application of Monte-Carlo statistical experiments in design of ocean engineering - Estimating the parameters, models and probabilities显示文摘Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long- term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms. | Liu Defu, Shi Jiangang and Zhou Zhigang Department of Ocean Engineering and Naval Architecture, Tianjin University. Tianjin, China Business & Project Division China Offshore Industrial Corporation (COIC).No. 10 Beixiaojie,Yuetan,BeijingsChina | 1990 | Acta Oceanologica Sinica1990，9，4： | 2 |
| 12 | 调和级数的奇妙特性显示文摘本文通过两个命题研究了将调和级数去掉分母含有的某类数字后所得级数的收敛性,并给出其和的误差估计式。调和级数,子级数,级数和。 | 朱辉 | 1997 | 渤海大学学报(自然科学版)1997，22，1： | 1 |
| 13 | THREE METHODS FOR ESTIMATING TURBULENT STRESS AND DRAG COEFFICIENT IN TIDAL CURRENTS OF THE HANGZHOU BAY显示文摘In this paper, we employed three metbods for measuring and estimating the turbulent stress and the results obtained were in good agreement with each other. The first method is a direct application of the momentum equations; the second one is based on the integration of momentum equations over an area, by which an overall estimate of the stress term for the area can be obtained; while the third one makes use of the energy equation and from which the estimate of the drag coefficient is deduced. | 方国洪 李身铎 曹德明 | 1987 | Chinese Science Bulletin1987，32，4： | 1 |
| 14 | DISPERSED PHASE HOLDUP AND DROP SIZE DISTRIBUTION IN A ROTATING PERFORATED DISK CONTACTOR显示文摘Hydrodynamic characteristics of rotating perforated disk contactor(RPDC)were studied with emulsionwater system.The emulsion was dispcrsed in water and its holdup was measured.The effects of columndimensions and operating conditions on holdup and characteristic velocity were studied.By using the methodof dimensional analysis,the authors obtained two experimental correlations for estimating holdup and characteristic velocity respectively.Drop size distribution was studied photographically.The experimental results showedthat drop size distribuiion could be described by upper-limit log-normal distribution. | 冯毓如 裘元焘 时钧 | 1991 | Chinese Journal of Chemical Engineering1991，，1： | 1 |
| 15 | Some Preliminary Results on Pilot Study of Global Change in China显示文摘On the basis of existing data and research results the changes of life supporting environment in China in the history are briefly described. The differences between regional climate variations and climate jump are the very important features and phenomena in estimating the trend of environmental evolution in the future. Finally, it is pointed out that sensitive zone is an ideal place to study global change. Many evidences show that the response of environmental elements in the sensitive zones to global change events is very obvious, so that much attention should be paid to the study of sensitive zone. | 陈泮勤 严中伟 | 1993 | Advances in Atmospheric Sciences1993，10，2： | 1 |
| 16 | On a General Class of Semiparametric Hazards Regression Models for Recurrent Gap Times显示文摘In the article,we investigate a general class of semiparametric hazards regression models for recurrent gap times.The general class includes the proportional hazards model,the accelerated failure time model and the accelerated hazards models as special cases.The model is flexible in modelling recurrent gap times since a covariate effect is identified as having two separate components,namely a time-scale change on hazard progression and a relative hazards ratio.In order to infer the model parameters,the procedure is proposed based on estimating equations.The asymptotic properties of the proposed estimators are established and the finite sample properties are investigated via simulation studies.In addition,a lack of fit test is presented to assess the adequacy of the model and an application of data from a bladder cancer study is reported for illustration. | Qin JIANG Hui ZHAO Hong QIN | 2019 | Acta Mathematicae Applicatae Sinica2019，35，3： | 1 |
| 17 | Estimating Canopy Nitrogen Contents of an Apple Tree Using Hyperspectral Remote Sensing显示文摘Estimating an apple tree canopy nitrogen contents using hyperspectral techniques is important in theoretical and realistic significance for fertilization and management.Taking 80 Fuji apple trees at the early fruiting stage as the research objects,the hyperspectral characteristics of the apple canopy were analyzed systematically.The apple canopy hyperspectral and the canopy nitrogen contents were measured respectively.The canopy hyperspectral characteristics under different nitrogen contents were analyzed and selected the sensitive wave bands.The apple canopy nitrogen content monitoring models were established by using multiple regression method,robust regression and BP neural network method.The results showed that the canopy hyperspectral reflectance had obvious differences under different nitrogen contents.The sensitive bands concentrate on 724~1136 nm.Estimation models based on hyperspectral indices are not ideal.Models based on robust regression(M regression)and BP neural network are better than multiple statistical model,and the accuracy of the BP neural network monitoring model is the best.The results of the study provide a certain reference for estimating apple nutrition using hyperspectral technology. | Xicun ZHU Lulu GAO Xianyi FANG Gengxing ZHAO Ling WANG | 2016 | 遥感科学(中英文版)2016，4，2： | 1 |
| 18 | Empirical likelihood for balanced ranked-set sampled data显示文摘Ranked-set sampling(RSS) often provides more efficient inference than simple random sampling(SRS).In this article,we propose a systematic nonparametric technique,RSS-EL,for hypoth-esis testing and interval estimation with balanced RSS data using empirical likelihood(EL).We detail the approach for interval estimation and hypothesis testing in one-sample and two-sample problems and general estimating equations.In all three cases,RSS is shown to provide more efficient inference than SRS of the same size.Moreover,the RSS-EL method does not require any easily violated assumptions needed by existing rank-based nonparametric methods for RSS data,such as perfect ranking,identical ranking scheme in two groups,and location shift between two population distributions.The merit of the RSS-EL method is also demonstrated through simulation studies. | LIU TianQing LIN Nan ZHANG BaoXue | 2009 | Science China Mathematics2009，52，6： | 1 |
| 19 | Significance of tumor-infiltrating immunocytes for predicting prognosis of hepatitis B virus-related hepatocellular carcinoma显示文摘BACKGROUND Hepatitis B virus (HBV) has been recognized as a leading cause of hepatocellular carcinoma (HCC). Numerous reports suggest that immune infiltration can predict the prognosis of HCC. Nonetheless, no creditable markers for prognosis of HBV-related HCC have been established by systematically assessing the immune-related markers based on tumor transcriptomes. AIM To establish an immune-related marker based on the cell compositions of immune infiltrate obtained based on tumor transcriptomes, so as to enhance the prediction accuracy of HBV-related HCC prognosis. METHODS RNA expression patterns as well as the relevant clinical data of HCC patients were obtained from The Cancer Genome Atlas. Twenty-two immunocyte fraction types were estimated by cell type identification by estimating relative subsets of RNA transcripts. Subsequently, the least absolute shrinkage and selection operator (LASSO) Cox regression model was employed to construct an immunoscore based on the immunocyte fraction types. Afterwards, the receiver operating characteristic (ROC) curve, Kaplan-Meier, and multivariate Cox analyses were performed. Additionally, a nomogram for prognosis that integrated the immunoscore as well as the clinical features was established. Meanwhile, the correlation of immunoscore with immune genes was also detected, and gene set enrichment analysis (GSEA) of the immunoscore was conducted. RESULTS A total of 22 immunocyte fraction types were predicted and compared among the tumor as well as non-tumor samples. An immunoscore was constructed through adopting the LASSO model, which contained eight immunocyte fraction types. Meanwhile, the areas under the ROC curves for the immunoscore biomarker prognostic model were 0.971, 0.912, and 0.975 for 1-, 3-, and 5-year overall survival (OS), respectively. Difference in OS between the high-immunoscore group and the low-immunoscore group was statistically significant [hazard ratio (HR)= 66.007, 95% confidence interval (CI): 8.361-521.105;P < 0.0001]. Moreover, multivariable analysis showed that the immunoscore was an independent factor for predicting the prognosis (HR = 2.997, 95%CI: 1.737-5.170). A nomogram was established, and the C-index was 0.757 (95%CI: 0.648-0.866). The immunoscore showed a significant negative correlation with the expression of PD-1 (P = 0.024), PD-L1 (P = 0.026), PD-L2 (P = 0.029), and CD27 (P = 0.033). Eight pathways were confirmed by GSEA. CONCLUSION The established immunoscore can potentially serve as a candidate marker to estimate the OS for HBV-related HCC cases. | Qi-Feng Chen Wang Li Pei-Hong Wu Lu-Jun Shen Zi-Lin Huang | 2019 | World Journal of Gastroenterology2019，25，35： | 1 |
| 20 | Shock Compression of Matter From Low Density to Relativistic Density显示文摘Shock-waves with strong gradients in pressure and density are often used to compress matter. Usually, temperature increases when the material is compressed and the temperature becomes | HE Yi-guang | 2008 | Annual Report of China Institute of Atomic Energy2008，，1： | 0 |
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