On the Accuracy Assessment of the Latest Releases of GOCE Satellite-Based Geopotential Models with EGM2008 and Terrestrial GPS/Levelling and Gravity Data over Egypt

The Global Geopotential Models (GGMs) of GOCE (Gravity Recovery and steady- state Ocean Circulation Explorer) differ globally as well as regionally in their accuracy and resolution based on the maximum degree and order (d/o) of the fully normalized spherical harmonic (SH) coefficients, which express each GGM. The main idea of this study is to compare the free-air gravity anomalies and quasi geoid heights determined from several recent GOCE-based GGMs with the corresponding ones from the Earth Gravitational Model 2008 (EGM2008) over Egypt on the one hand and with ground-based measurements on the other hand. The results regarding to the comparison of GOCE-based GGMs with terrestrial gravity and GPS/levelling data provide better improvement with respect to EGM2008. The 4th release GOCE-based GGM developed with the use of space-wise solution strategy (SPW_R4) approximates the gravity field well over the Egyptian region. The SPW_R4 model is accordingly suggested as a reference model for recovering the long wavelength (up to SH d/o 200) components of quasi geoid heights when modelling the gravimetric quasi-geoid over the Egypt. Finally, three types of transformation models: Four-, Five- and Seven-parameter transformations have been applied to reduce the data biases and to provide a better fitting of quasi geoid heights obtained from the studied GOCE-based GGMs to those from GPS/levelling data. These models reveal that the standard deviation of vertical datum over Egypt is at the level of about 32 cm.

A Model-free Approach to Fault Detection of Continuous-time Systems Based on Time Domain Data

In this paper, a model-free approach is presented to design an observer-based fault detection system of linear continuoustime systems based on input and output data in the time domain. The core of the approach is to directly identify parameters of the observer-based residual generator based on a numerically reliable data equation obtained by filtering and sampling the input and output signals.

Stellar spectra association rule mining method based on the weighted frequent pattern tree

Effective extraction of data association rules can provide a reliable basis for classification of stellar spectra. The concept of stellar spectrum weighted itemsets and stellar spectrum weighted association rules are introduced, and the weight of a single property in the stellar spectrum is determined by information entropy. On that basis, a method is presented to mine the association rules of a stellar spectrum based on the weighted frequent pattern tree. Important properties of the spectral line are highlighted using this method. At the same time, the waveform of the whole spectrum is taken into account. The experimental results show that the data association rules of a stellar spectrum mined with this method are consistent with the main features of stellar spectral types.

Data Transfer Over the Internet for Real Time Applications

Efficient real time data exchange over the Internet plays a crucial role in the successful application of web-based systems. In this paper, a data transfer mechanism over the Internet is proposed for real time web based applications. The mechanism incorporates the eXtensible Markup Language （XML） and Hierarchical Data Format （HDF） to provide a flexible and efficient data format. Heterogeneous transfer data is classified into light and heavy data, which are stored using XML and HDF respectively; the HDF data format is then mapped to Java Document Object Model （JDOM） objects in XML in the Java environment. These JDOM data objects are sent across computer networks with the support of the Java Remote Method Invocation （RMI） data transfer infrastructure. Client＇s defined data priority levels are implemented in RMI, which guides a server to transfer data objects at different priorities. A remote monitoring system for an industrial reactor process simulator is used as a case study to illustrate the proposed data transfer mechanism.

Image Processing on Geological Data in Vector Format and Multi-Source Spatial Data Fusion

The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper converts the vector data into 8 bit images according to their importance to mineralization each by programming. We can communicate the geological meaning with the raster images by this method. The paper also fuses geographical data and geochemical data with the programmed strata data. The result shows that image fusion can express different intensities effectively and visualize the structure characters in 2 dimensions. Furthermore, it also can produce optimized information from multi-source data and express them more directly.

Sources of China's Economic Growth:An Analysis Based on Nonparametric Accounting Method

This paper improves the slacks-based method for estimating inefficiency,derives the criteria for the selection of the weights of output and input inefficiencies in the objective function,and creates a new nonparametric method for accounting economic growth.Based on this method,the paper estimates the sources of China s economic growth from 1978 to 2013.Our findings suggest that factor input and especially capital is a major source of economic growth for China as a whole and its major regions,and that economic growth in recent years is increasingly dependent on capital.For a rather long period of time before 2005,China s northeast,central and western regions lagged behind the eastern region in terms of economic growth,and TFP and factor input are major reasons behind such regional growth disparities.Although other regions have narrowed their disparities with and even overtaken the eastern region in terms of economic growth,the key driver is the rapid increase in the contribution of factor input.Advanced technologies of eastern region should be utilized to promote TFP progress in other regions,which is vital to economic growth in these regions and China as a whole.

FoxBASE求解线性方程组

本文利用数据库与矩阵之间的相似性。

dBASEⅢ与外部接口间数据传递的通用方法

根据由dBASEⅢ数据库在计算机内部的存储形式,描述了数据库与外部接口间直接数据传递的通用方法,并提出了一种通用程序加以实现.

RELIABILITY ASSESSMENT OF ENTROPY METHOD FOR SYSTEM CONSISTED OF IDENTICAL EXPONENTIAL UNITS

The reliability assessment of unit-system near two levels is the mostimportant content in the reliability multi-level synthesis of complex systems. Introducing theinformation theory into system reliability assessment, using the addible characteristic ofinformation quantity and the principle of equivalence of information quantity, an entropy method ofdata information conversion is presented for the system consisted of identical exponential units.The basic conversion formulae of entropy method of unit test data are derived based on the principleof information quantity equivalence. The general models of entropy method synthesis assessment forsystem reliability approximate lower limits are established according to the fundamental principleof the unit reliability assessment. The applications of the entropy method are discussed by way ofpractical examples. Compared with the traditional methods, the entropy method is found to be validand practicable and the assessment results are very satisfactory.

High-resolution azimuth estimation algorithm based on data fusion method for the vector hydrophone vertical array

To aim at the problem that the horizontal directivity index of the vector hy- drophone vertical array is not higher than that of a vector hydrophone, the high-resolution azimuth estimation algorithm based on the data fusion method was presented. The proposed algorithnl first employs MUSIC algorithm to estimate the azimuth of each divided sub-band signal, and then the estimated azimuths of multiple hydrophones are processed by using the data fusion technique. The high-resolution estimated result is achieved finally by adopting the weighted histogram statistics method. The results of the simulation and sea trials indicated that the proposed algorithm has better azimuth estimation performance than MUSIC algorithm of a single vector hydrophone and the data fusion technique based on the acoustic energy flux method. The better performance is reflected in the aspects of the estimation precision, the probability of correct estimation, the capability to distinguish multi-objects and the inhibition of the noise sub-bands.

Outlier detection based on multi-dimensional clustering and local density

Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outlier. In this work, an effective outlier detection method based on multi-dimensional clustering and local density(ODBMCLD) is proposed. ODBMCLD firstly identifies the center objects by the local density peak of data objects, and clusters the whole dataset based on the center objects. Then, outlier objects belonging to different clusters will be marked as candidates of abnormal data. Finally, the top N points among these abnormal candidates are chosen as final anomaly objects with high outlier factors. The feasibility and effectiveness of the method are verified by experiments.

A simple data assimilation method for improving the MODIS LAI time-series data products based on the object analysis and gradient inverse weighted filter

A simple data assimilation method for improving estimation of moderate resolution imaging spectroradiometer （MODIS） leaf area index （LAI） time-series data products based on the gradient inverse weighted filter and object analysis is proposed. The properties and quality control （QC） of MODIS LAI data products are introduced. Also, the gradient inverse weighted filter and object analysis are analyzed. An experiment based on the simple data assimilation method is performed using MODIS LAI data sets from 2000 to 2005 of Guizhou Province in China.

PRP-Type Direct Search Methods for Unconstrained Optimization

Three PRP-type direct search methods for unconstrained optimization are presented. The methods adopt three kinds of recently developed descent conjugate gradient methods and the idea of frame-based direct search method. Global convergence is shown for continuously differentiable functions. Data profile and performance profile are adopted to analyze the numerical experiments and the results show that the proposed methods are effective.

基于点模式匹配的直流输电VBE设备电路板缺陷检测方法

随着特高压直流输电技术飞速发展,换流阀阀基电子VBE(valve base electronics)设备的稳定性对于保障直流输电的可靠性和效率至关重要。VBE设备电路板缺陷,如短路和失效元件,直接影响直流系统稳定性,而现有的检测方法,包括人工显微镜检查和自动检测算法,常受限于效率低和准确性不足。针对该问题,提出一种基于点模式匹配的自动视觉检测方法,通过生成代表关键区域的点模式并进行匹配来提高检测的效率和准确率。通过实验验证,所提方法在检测速度和准确性方面相较于传统方法有显著提升,适合于生产线上的快速质量控制,为提高直流输电设备的质量提供了有效的技术方案。

数据要素市场化配置对企业数据要素活力的影响与机制——基于外部环境和企业自身视角

数据交易平台建设作为数据要素市场化配置的重要内容,已成为促进数字经济发展、实现经济高质量发展的重要抓手,科学评估其政策效应对激活企业数据要素活力具有重要意义。基于外部环境和企业自身视角,运用2011—2022年我国沪深A股上市公司数据,将数据交易平台设立视为准自然实验,利用多期双重差分法研究数据要素市场化配置对企业数据要素活力的影响及其作用机制。研究发现,数据要素市场化配置能够激发企业数据要素活力,此结论经过一系列稳健性检验后依然成立。机制检验结果表明,数据要素市场化配置有利于降低企业成本、促进企业数字技术创新和提升企业资源配置效率,从而激发企业数据要素活力,并且数据经纪人集聚和数据基础设施完善能够进一步强化这种促进作用。进一步研究发现,数据要素市场化配置对企业数据要素活力的影响存在行业垄断程度和企业生命周期异质性。相较于高垄断行业企业、成熟期企业和衰退期企业,数据要素市场化配置对低垄断行业企业和成长期企业数据要素活力的促进作用更大。此外,数据要素市场化配置能够抑制企业避税行为。因此,应继续深化数据要素市场化改革,大力布局数据交易平台建设;优化数据要素市场生态,构建数据要素创新体系;培育和发展数据经纪人,加强数据基础设施建设;因业、因企制宜实施数据要素市场化改革;增强数据要素市场化改革与税收征管的联动作用,为深化数据要素市场化改革和提升企业数据要素活力提供重要参考。

实物地质资料知识库建设初探

知识库是人工智能和数据库等当前两项重要计算机技术的有机结合,将知识库应用于实物地质资料管理服务领域,可以为用户在利用实物地质资料时提供更多信息知识参考,加速服务智能化转变。本文首先分析了实物地质资料知识库建设的实际需求,包括馆藏机构的发展需要、资源体系建设的重要内容以及社会化服务的发展趋势。然后探讨了知识库建设的基本要素,主要包括资源要素、技术要素和服务要素。最后提出了建设建议,包括要完善相关配套资料的收集,为知识库建设提前做好完整丰富的材料储备;开展配套资料收集管理技术方法研究,对所收集的资料进行系统化加工和归档;以及与相关单位建立合作机制,夯实信息共享合作基础。

基于ICN的数据中心服务调度方法优化设计

虚拟化技术使得数据中心的服务可以在任意位置灵活部署,同时也引入如何合理调度用户的服务请求到这些位置的问题。本文提出一种基于信息中心网络(ICN)技术的数据中心服务调度方法——ICSS。基于ICN标识与地址分离特性,ICSS可直接在网络层数据平面级别提供分布式服务调度功能,网络层数据平面支持线速转发,能实时快速处理服务请求的调度决策,避免传统调度方案在路径延伸和传输时延方面的不足。ICSS考虑服务请求大小及虚拟机资源负载情况,基于PSO-GA算法进行服务调度,以优化服务响应时间和虚拟机负载均衡程度,提高网络的扩展性。为实现与现有数据中心IP业务的无缝承接,本文设计一种ICN协议与IP网络协议的转换方法,确保ICSS对客户端和服务端透明。实验表明,相较于传统的加权最小连接算法(WLC),ICSS的服务完成时间平均减少约21%,CPU、内存资源利用率方差分别平均减少约10%、10%;相较于网络层分布式服务调度方法——分布式计算感知调度算法(CArDS),ICSS在服务请求数量较多时具有更少的服务完成时间,CPU、内存资源利用率方差分别平均减少约32%、29%,转发表表项平均减少约97%,控制开销数量平均减少约98%。ICSS在服务完成时间、负载均衡以及可扩展性方面具有明显优势。

排污权交易对福建绿色发展效率的影响研究

绿色发展是一种基于传统发展模式的可持续发展的创新模式,提高绿色发展的关键是提高绿色发展效率。为进一步检验排污权交易政策对福建省绿色发展效率的影响,该文首先采用数据包络分析方法的超效率模型测算绿色发展效率,其次将2011-2020年未实际开展排污权交易的省份作为控制组,通过合成控制法分析排污权交易对福建省绿色发展效率的影响情况,并进行了稳健性检验。结果表明:(1)资源配置效率是导致绿色发展效率不均衡的关键因素。(2)福建省排污权交易政策的实施对绿色发展效率呈促进作用,从拟合的结果来看,2015年若未实施排污权交易,其绿色发展效率均值将比实际值有所下降。

融入思政元素的“数据分析”课程教学改革方法研究

大数据时代,数据分析成为各个领域长期发展的必要手段。“数据分析”课程作为一门选修课,主要训练学生掌握解码大数据背后时代发展规律的方法,为培养医学、物理、化学、经济等专业学生的数据处理能力奠定良好基础。主要针对“数据分析”课程的教学目标以及目前教学过程中存在的问题,提出具体的教学改革措施,从优化课程内容、改善教学方法、融入思政元素、增加实训练习和改革考核模式等五个方面,以提高课程教学质量和增强学生应用能力的培养。

基础地理信息数据与基础地理实体数据转换浅析

基础地理信息数据向基础地理实体数据转换,是新型基础测绘体系建设的基础工作。基础地理信息数据在政府决策、城市规划、军事国防等领域仍然提供有力的服务保障,不能完全被替代。针对基础地理信息数据与基础地理实体数据互相转换的可行性,通过对存量基础地理信息数据成果与基础地理实体数据在数据表达、数据内容方面的对比分析,提出了通过制作数据转换知识库,程序化实现基础地理信息数据与基础地理实体数据的互相转换。