An approach to estimate tree height using PolInSAR data constructed by the Sentinel-1 dual-pol SAR data and RVoG model

We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is unavailable.The S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were obtained.The proposed approach was first verified in simulation with satisfactory results.It was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,USA.According to local observations and forest descriptions,the range of estimated tree heights was overall reasonable.Comparing the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is possible.For instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be explored.Also,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season.

Comparison of two statistical methods for handling missing values of quantitative data in Bayesian N-of-1 trials: a simulation study

Background:Missing data are frequently occurred in clinical studies.Due to the development of precision medicine,there is an increased interest in N-of-1 trial.Bayesian models are one of main statistical methods for analyzing the data of N-of-1 trials.This simulation study aimed to compare two statistical methods for handling missing values of quantitative data in Bayesian N-of-1 trials.Methods:The simulated data of N-of-1 trials with different coefficients of autocorrelation,effect sizes and missing ratios are obtained by SAS 9.1 system.The missing values are filled with mean filling and regression filling respectively in the condition of different coefficients of autocorrelation,effect sizes and missing ratios by SPSS 25.0 software.Bayesian models are built to estimate the posterior means by Winbugs 14 software.Results:When the missing ratio is relatively small,e.g.5%,missing values have relatively little effect on the results.Therapeutic effects may be underestimated when the coefficient of autocorrelation increases and no filling is used.However,it may be overestimated when mean or regression filling is used,and the results after mean filling are closer to the actual effect than regression filling.In the case of moderate missing ratio,the estimated effect after mean filling is closer to the actual effect compared to regression filling.When a large missing ratio(20%)occurs,data missing can lead to significantly underestimate the effect.In this case,the estimated effect after regression filling is closer to the actual effect compared to mean filling.Conclusion:Data missing can affect the estimated therapeutic effects using Bayesian models in N-of-1 trials.The present study suggests that mean filling can be used under situation of missing ratio≤10%.Otherwise,regression filling may be preferable.

ENVISAT-1卫星测高数据编辑标准的研究

介绍了环境卫星(ENVISAT-1)的基本情况及其主要技术参数,在借鉴其他卫星测高数据编辑标准和大量统计基础上,制定了ENVISAT-1卫星的数据编辑标准,包括冰标志和S波段异常的确定,并给出了各改正项合理的限值。

Envisat-1双极化雷达数据建模及应用

根据欧空局Envisat-1卫星上ASAR传感器的系统参数和双极化特点,利用AIEM模型模拟,建立了裸露地表同极化后向散射模型和粗糙度参数计算模型。前者把同极化总后向散射系数表达成入射角和两个地表参数(土壤水分和粗糙度)的函数;后者给出了用双极化雷达数据计算粗糙度的方法。把这两个模型结合,用于土壤水分反演,分别用模拟数据和实测数据验证,良好的结果证明了这两个模型的可靠性和实用性。双极化后向散射模型的建立,将为以后PALSAR(日本)和RADARSAT-2(加拿大)多极化雷达数据的应用打下基础。

2.5Gb/s Monolithic IC of Clock Recovery,Data Decision,and 1∶4 Demultiplexer

A high integrated monolithic IC, with functions of clock recovery, data decision, and 1 ： 4 demultiplexer,is implemented in 0.25μm CMOS process for 2.5Gb/s fiber-optic communications. The recovered and frequency divided 625MHz clock has a phase noise of -106.26dBc/Hz at 100kHz offset in response to a 2.5Gb/s PRBS input data （2^31-1）. The 2.5Gb/s PRBS data are demultiplexed to four 625Mb/s data. The 0.97mm× 0.97mm IC consumes 550mW under a single 3.3V power supply （not including output buffers）.

Oracle10gRAC下“军卫一号”数据库升级和OracleDataGuard部署

目的:将"军卫一号"操作系统从32位Windows 2000升级为64位Windows 2003,Oracle数据库从8.17升级为10g(64位)。解决服务器负载过重及并发用户连接数过多导致数据库无法连接的问题。方法:在升级测试的基础下,完成数据迁移,建立RAC,部署Data Guard。结果:实现数据库升级,系统运行速度大大提高,使"军卫一号"数据库达到高效和高可用。结论:将数据库从32位Oracle8.17升级为64位Oracle10g RAC是一个投入低、效益高的方法。

基于1+X证书的高职院校人才培养模式与证书考核工作探究——以“工业数据采集与边缘服务”(中级)等级证书为例

以“工业数据采集与边缘服务”职业技能等级(中级)证书人才培养及考核为切入点,根据实际岗位需求,深入分析中级证书考核标准,提出模块化融合型人才培养模式,并结合专业课程开发、考核站点建设的经验,在强化模拟训练基础上,建立标准化培训与考核流程,切实提高学生专业实践能力和1+X中级证书考证通过率。

1+X证书制度下大数据与会计专业建设探究

高职院校作为高等职业教育和1+X证书制度试点的主要阵地,应积极探索1+X证书制度实施的路径,重构大数据与会计专业课程体系,优化专业人才培养方案,创新人才培养和职业技能培训模式,加强师资队伍建设,加强校企合作,实现精准育人和高水平育人。

Development and Integration of a Data Acquisition System for SST-1 Phase-1 Plasma Diagnostics

Long pulse （of the order of 1000 s or more） SST-1 tokamak experiments demand a data acquisition system that is capable of acquiring data from various diagnostics channels without losing useful data （and hence physics information） while avoiding unnecessary generation of a large volume data. SST-1 Phase-1 tokamak operation has been envisaged with data acquisition of several essential diagnostics channels. These channels demand data acquisition at a sampling rate ranging from 1 kilo samples per second （KSPS） to 1 mega samples per second （MSPS）. Considering the technical characteristics and requirements of the diagnostics, a data acquisition system based on PXI and CAMAC has been developed for SST-1 plasma diagnostics. Both these data acquisition systems are scalable. Present data acquisition needs involving slow plasma diagnostics are catered by the PXI based data acquisition system. On the other hand, CAMAC data acquisition hardware meets all requirements of the SST-1 Phase-1 fast plasma diagnostics channels. A graphical user interface for both data acquisition systems （PXI and CAMAC） has been developed using LabVIEW application development software. The collected data on the local hard disk are directly streaming to the central server through a dedicated network for post-shot data analysis. This paper describes the development and integration of the data acquisition system for SST-1 Phase-1 plasma diagnostics. The integrated testing of the developed data acquisition system has been performed using SST-1 central control and diagnostics signal conditioning units. In the absence of plasma shots, the integrated testing of the data acquisition system for the initial diagnostics of SST-1 Phase-1 operation has been performed with simulated physical signals. The primary engineering objective of this integrated testing is to validate the performance of the developed data acquisition system under simulated conditions close to that of actual tokamak operation. The data acquisition is synchronized with a clock and trigger provided by the central timing system.

全息血管硬度分析技术评价不同病程1型糖尿病患儿颈动脉弹性功能

目的应用全息血管硬度分析技术评价1型糖尿病(T1DM)患儿颈动脉弹性功能与糖尿病病程和血糖控制情况的相关性。资料与方法前瞻性收集2019年9月—2021年11月河南省胸科医院儿科、河南省人民医院儿科、河南省儿童医院内分泌遗传代谢科已确诊的T1DM患儿75例,按照T1DM患儿病程分为长病程组(病程≥5年)30例,短病程组(病程<5年)45例;同时收集年龄、性别相匹配的正常对照组30例。用全息血管硬度分析技术测量颈总动脉血管收缩期直径、血管位移、脉搏波传导速度(PWV)和硬度系数、颈总动脉内-中膜厚度;同期收集血糖及血脂指标,比较3组间各参数的差异。结果长病程组、短病程组空腹血糖、糖化血红蛋白和内-中膜厚度均高于对照组,差异有统计学意义(P均<0.05);3组PWV、硬度系数、血管位移差异有统计学意义(F=22.854、16.811,H=33.214,P均<0.001)。病程与PWV、硬度系数具有相关性(r=0.621、0.517,P<0.001);糖化血红蛋白与PWV具有相关性(r=0.562,P<0.001)。结论T1DM患儿早期即可出现颈动脉弹性减退,高血糖持续时间越长,动脉弹性受损程度越重。全息血管硬度分析技术是一种简单有效且无创的动脉弹性评估方法,为临床提供诊疗依据。

大数据时代高职院校会计专业“1+X”课证融合实施路径研究

“1+X”证书制度是提高人才培养质量的重要举措,开启了职业院校人才培养新模式。随着大数据、云计算等人工智能新技术在会计领域的推广应用,企业对财会人员的职业素养提出了更高的要求。高职院校可以从改革专业人才培养模式、构建课证融通的课程体系、建设高水平职业技能教师团队和推进校企深度合作等方面探索会计专业高质量发展和人才培养新路径。

Asymptotic inference for AR(1) panel data

A general asymptotic theory is given for the panel data AR(1) model with time series independent in different cross sections. The theory covers the cases of stationary process, local to unity process, unit root process, mildly integrated, mildly explosive and explosive processes. It is assumed that the cross-sectional dimension and time-series dimension are respectively N and T. The results in this paper illustrate that whichever the process is, with an appropriate regularization, the least squares estimator of the autoregressive coefficient converges in distribution to a normal distribution with rate at least O(N-1/3). Since the variance is the key to characterize the normal distribution, it is important to discuss the variance of the least squares estimator. We will show that when the autoregressive coefficient ρ satisfies |ρ| < 1, the variance declines at the rate O((NT)-1), while the rate changes to O(N^(-1) T^(-2)) when ρ = 1 and O(N^(-1)ρ^(-2 T+4)) when |ρ| > 1. ρ = 1 is the critical point where the convergence rate changes radically. The transition process is studied by assuming ρ depending on T and going to 1. An interesting phenomenon discovered in this paper is that, in the explosive case, the least squares estimator of the autoregressive coefficient has a standard normal limiting distribution in the panel data case while it may not has a limiting distribution in the univariate time series case.

The 1st International Conference on Datadriven Knowledge Discovery:When Data Science Meets Information Science.June 19–22,2016,Beijing·China

The 1st International Conference on Data-driven Knowledge Discovery： When Data Science Meets Information Science took place at the National Science Library （NSL）, Chinese Academy of Sciences （CAS） in Beijing from June 19 till June 22, 2016. The Conference was opened by NSL Director Xiangyang Huang, who placed the event within the goals of the Library, and lauded the spirit of intemational collaboration in the area of data science and knowledge discovery. The whole event was an encouraging success with over 370 registered participants and highly enlightening presentations. The Conference was organized by the Journal of Data andlnformation Science （JDIS） to bring the Joumal to the attention of an international and local audience.

Scientific data and their release of Chang'E-1 and Chang'E-2

The Chang'E-1 and Chang'E-2 missions have successfully obtained a huge amount of lunar scientific data, through the seven onboard instruments including a CCD stereo camera, a laser altimeter, an interference imaging spectrometer, an X-ray spectrometer, a microwave radiometer, a high-energy particle detector and a solar-wind ion detector. Most of the Chang'E data are now publicly available to the science community, and this article serves as an official guide on how these data are classified and organized, and how they can be retrieved from http://159.226.88.59:7779/CE1OutENGWeb/. This article also presents the detailed specifications of various instruments and gives examples of research progress made based on these instruments.

3D motion and geometric information system of single-antenna radar based on incomplete 1D range data

A 3D motion and geometric information system of single-antenna radar is proposed,which can be supported by spotlight synthetic aperture radar（SAR） system and inverse SAR（ISAR） system involving relative 3D motion of the rigid target.In this system,applying the geometry invariance of the rigid target,the unknown 3D shape and motion of the radar target can be reconstructed from the 1D range data of some scatterers extracted from the high-resolution range image.Compared with the current 1D-to-3D algorithm,in the proposed algorithm,the requirement of the 1D range data is expanded to incomplete formation involving large angular motion of the target and hence,the quantity of the scatterers and the abundance of 3D motion are enriched.Furthermore,with the three selected affine coordinates fixed,the multi-solution problem of the reconstruction is solved and the technique of nonlinear optimization can be successfully utilized in the system.Two simulations are implemented which verify the higher robustness of the system and the better performance of the 3D reconstruction for the radar target with unknown relative motion.

“1+X”证书制度下《商务数据分析》课程改革探索——以柳州职业技术学院电子商务专业为例

在电子商务领域,商务数据蕴藏着巨大商机,数据分析已是电子商务从业人员不可或缺的一项重要技能。本文首先明确《商务数据分析》的课程目标与定位,提出《商务数据分析》教学中存在的问题,其次针对问题进行相应的改革探索,最后总结改革实施取得的成果及今后的反思与改进。

EXISTENCE OF POSITIVE SOLUTIONS FOR A CLASS OF PARABOLIC EQUATIONS WITH NATURAL GROWTH TERMS AND L^1 DATA

We study a class of nonlinear parabolic equations of the type：δb（u）/δt-div（a（x,t,u）△u）＋y（u）｜△u｜^2=f,where the right hand side belongs to L^1（Q）, b is a strictly increasing C^1-function and -div（a（x, t, u）△u） is a Leray-Lions operator. The function g is just assumed to be continuous on R and to satisfy a sign condition. Without any additional growth assumption on u, we prove the existence of a renormalized solution.

An adaptive physics-informed deep learning method for pore pressure prediction using seismic data

Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the great potential to deal with pore pressure prediction.However,most of the traditional deep learning models are less efficient to address generalization problems.To fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic data.Specifically,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss function.Through machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure prediction.The CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and Bowers methods is also proposed to build machine-learnable labels for solving the problem of few labels.To validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization ability.The adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data.

Case studies of ERS-1 altimeter data applicating in China Sea

The impact of ERS-1 altimeter significant wave height on analysis of wave field and wave pre- dictions is tested through analysis of selected cases. Application of the altimeter data may modifg initial tield and thus 24-hour prediction of significant wave height. However the variations in initial wave field almost make no effect on 48-hour predictions.

An Investigation of the Impact of Installation of Cd-Lined Irradiation Channel in NIRR-1 on Core Physics Data for ENAA

Prior to the installation of the Cd-liner in one of the large outer irradiation channels of NIRR-1, a Monte Carlo simulation was performed using MCNP5 version 1.4 code. This was done to investigate the effect of installation of Cd-liner in either an inner or outer irradiation channel on reactor physics parameters. Data obtained indicate that the core excess reactivity in both inner and outer irradiations channels is reduced by 3.60 ± 0.07 mk and 0.64 ± 0.06 mk, respectively. Considering the fact that NIRR-1 has a cold core excess reactivity of 3.77 mk, results obtained show that installation of the 1 mm thick Cd-sheet in one of the large outer irradiation channels would have no significant impact on the core physics data. After installation of a 1 mm Cd sheath in a large outer irradiation channel, the neutron flux distribution and the stability in the irradiation channels were monitored by foil activation method. Results indicate that the uniformity of neutron flux distribution in the irradiation channel is preserved and the neutron flux data were found to be comparable with the data obtained before the installation.