大数据助推我国智慧政府的发展

在智慧城市建设的背景下,我国政府正试图向智慧政府的方向发展,大数据无疑在提升政府服务水平和治理能力方面发挥着至关重要的作用。文章对大数据的内涵、特征及应用做了比较详细的介绍,进而介绍了智慧政府,并且提出在大数据时代,智慧政府如何顺数而为,紧跟大数据浪潮。

阿尔茨海默病患者脑体积与认知功能之间的相关性研究

目的:探讨阿尔茨海默病(Alzheimer′s disease,AD)患者的脑白质体积(white matter volume,WMV)、脑灰质体积(gray matter volume,GMV)、及脑脊液体积(cerebrospinal fluid volume,CSFV)与认知功能之间的相关性,分析其用于AD早期诊断的预测价值。方法:选择2018年9月-2020年9月就诊于南通大学附属医院神经内科门诊及住院诊治的AD患者18例作为AD组,纳入同期在我院进行体检的16例同龄正常人作为正常对照组(NC组)。采用神经功能影像学软件通过矩阵实验室(matrix laboratory,Matlab)使用顺数处理机(calculated by sequence processor,CAT12)计算WMV、GMV。收集入组者年龄、性别、高血压、糖尿病、蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)、即刻记忆、延迟记忆、连线测试、数字广度实验、波士顿命名等临床资料,分析脑体积与认知功能之间的相关性。通过ROC曲线分析CSFV、WMV、GMV对于AD早期诊断的价值。结果:WMV、GMV与年龄呈负相关,CSFV与年龄呈正相关,AD组及NC组在CSFV、GMV及WMV之间差异有统计学意义(P<0.05)。GMV、WMV、CSFV均与MoCA总评分有关。在MoCA评分分组间不同认知共障碍CSFV、GMV、WMV比较差异有统计学意义,认知功能正常患者GMV及WMV较中重度认知功能障碍患者增加,而CSFV较中重度认知功能障碍患者减少。WMV的AUC为0.96,较CSFV及GMV高。结论:尽管基于体素的形态学分析计算的脑体积尚未纳入诊断AD的生物标志物,但WMV、GMV、CSFV在AD及正常老年人间差异有统计学意义,结合神经心理评估可能有助于早期发现认知障碍和AD。

MINER RULE CONSIDERING FUZZINESS OF STRESS DAMAGE UNDER DIFFERENT LOAD SEQUENCES

Since the traditional Miner rule ignores the influence of the load sequence on the fatigue life, the fuzzy rules are used to analyze the fuzziness of the fatigue damage caused by the stress nearby the fatigue limit under different load sequences. The improved fuzzy Miner rule can reflect the influence of the load sequence on the fatigue life. Results of the example show that the prediction error can be reduced from 61.6% to 21.7%.

启迪幼儿智慧 促进加减法教学

探讨了幼儿数学教学中,遵循幼儿特点进行加减法教学的途径.

Effects of welding parameters and welding sequence on residual stress and distortion in Al6061-T6 aluminum alloy for T-shaped welded joint

The distribution of temperature and then the distribution of residual stress and distortion in the stiffened aluminum alloy Al6061-T6 plates under the metal inert gas(MIG)welding process were investigated by three dimensional thermo-mechanical coupled finite element model using Ansys software.The properties of materials were considered temperature-dependent and the filler metal was added to the workpiece by the element birth and death technique.In three modes of current,two different speeds and two various sequences,the distribution of residual stress and distortion were calculated and analyzed.The results showed that increase in welding speed decreased the vertical deflection in the plate,transverse shrinkage and angular distortion of plate and the lateral deflection of stiffener,but increased the maximum longitudinal tensile stress in the plate and stiffener.Furthermore,increase in current increased the residual stress and deformation in the plate and stiffener,and the change in the welding sequence changed the distribution of the distortion in the plate and the stiffener without significant change in the distribution of the longitudinal residual stress.

The Physical Significance of the Synthetic Running Correlation Coefficient and Its Applications in Oceanic and Atmospheric Studies

In order to study the temporal variations of correlations between two time series,a running correlation coefficient(RCC)could be used.An RCC is calculated for a given time window,and the window is then moved sequentially through time.The current calculation method for RCCs is based on the general definition of the Pearson product-moment correlation coefficient,calculated with the data within the time window,which we call the local running correlation coefficient(LRCC).The LRCC is calculated via the two anomalies corresponding to the two local means,meanwhile,the local means also vary.It is cleared up that the LRCC reflects only the correlation between the two anomalies within the time window but fails to exhibit the contributions of the two varying means.To address this problem,two unchanged means obtained from all available data are adopted to calculate an RCC,which is called the synthetic running correlation coefficient(SRCC).When the anomaly variations are dominant,the two RCCs are similar.However,when the variations of the means are dominant,the difference between the two RCCs becomes obvious.The SRCC reflects the correlations of both the anomaly variations and the variations of the means.Therefore,the SRCCs from different time points are intercomparable.A criterion for the superiority of the RCC algorithm is that the average value of the RCC should be close to the global correlation coefficient calculated using all data.The SRCC always meets this criterion,while the LRCC sometimes fails.Therefore,the SRCC is better than the LRCC for running correlations.We suggest using the SRCC to calculate the RCCs.

NEW FAMILY OF BIPOLAR SEQUENCES AND ITS CORRELATION SPECTRUM

Based on a class of bipolar sequences with two-values autocorrelation functions, a new family of bipolar sequences is constructed and its correlation spectrum is calculated. It is shown that the new family is optimal with respect to Welch's bound and is different from the small set of Kasami sequences, while both of them have the same correlation properties.

Enhancing manual P-phase arrival detection and automatic onset time picking in a noisy microseismic data in underground mines

Accurate detection and picking of the P-phase onset time in noisy microseismic data from underground mines remains a big challenge. Reliable P-phase onset time picking is necessary for accurate source location needed for planning and rescue operations in the event of failures. In this paper, a new technique based on the discrete stationary wavelet transform （DSWT）and higher order statist!cs, is proposed for processing noisy data from underground mines. The objectives of this method are to （1） Improve manual detection and tPicking of P-phase onset; and （ii） provide an automatic means of detecting and picking P-phase onset me accurately. The DSWT is first used to filter the signal over several scales. The manual P-phase onset detection and picking are then obtained by computing the signal energy across selected scales with frequency bands that capture the signal of interest. The automatic P-phase onset, on the other hand, is achieved by using skewness- and kurtosis-based criterion applied to selected scales in a time-frequency domain. The method was tested using synthetic and field data from an underground limestone mine. Results were compared with results obtained by using the short-term to long-term average （STA/LTA） ratio and that by Reference Ge et al. （2009）. The results show that the me!hod provides a more reliable estimate of the P-phase onset arrival than the STA]LTA method when the signal to noise ratio is very low. Also, the results obtained from the field data matched accurately with the results from Reference Ge et al. （2009）.

Low cyclic fatigue performance of concrete-filled steel tube columns

Eight concrete-filled steel tubular(CFT) columns were tested subjected to cyclic loading under constant axial load. Experimental parameters included axial compression ratio, loading sequences, and strength of concrete and steel. The seismic performance of CFT columns and failure modes were analyzed. The test results show that different axial load ratios and loading sequences have effects on the load carrying capacity, ductility and energy dissipation capacity of CFT columns, as well as the failure modes of the CFT columns. The failure pattern can be categorized into two types: local buckling failure of steel tube in compression zone, and low cycle fatigue tearing rupture failure of steel tube. The seismic behavior was evaluated through the energy index obtained from each cycle.

3D numerical parametric study of the influence of open-pit mining sequence on existing tunnels

The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence on existing tunnels such as displacements of the lining and additional loads on the lining. In this paper, three-dimensional numerical parametric study is performed to explore this complex interaction. This study investigates the effects of different parameters that may affect the tunnel response. These parameters are： excavation sequence method, horizontal/vertical stress ratio, slope angle, and tunnel diameter. This study shows that the mining sequence affects the stability of the tunnels. The open-pit mining activities lead to both higher axial forces in rock bolts and normal forces and bending moments in the lining. The results of the analysis also demonstrate that the mining sequence causes tunnel heave and significant tensile forces in the lining. Based on the study in this paper a better understanding of the interaction between oDen-oit minin~ seouence and tunnels will he ohtained

EPR Study of a New Crystal of the Binuclear Copper(Ⅱ) Cluster Compound- Cu_2(α-C_(10)H_7CH_2CO_2)_4-(DMF)_2 ·(DMF)_2·H_2O

In this paper, single crystal EPR study of a new binuclear copper (Ⅱ) cluster compound-[Cu2(α-C(10) H7CH2CO2)4 (DMF)2]·[DMF]2·H2O](DMF= (CH3)2NCOH) at room temperature is reported. The lines of △Ms=±1 allowing transition and △M=2 forbiding transition are shown in EPR spectra. The experimental data are consistent with the calculated results by the leastsquares fitting prograrn in three principal planes of g and D tensors. The spin Hamiltonian parameters are as follows: gx=2. 1482, gy=2. 0529 ,gz=2. 3905, D= 0. 348 cm￣(-1) and E =0. 01 cm-1. The diagrams of the energy levels have been obtained when the magnetic field is oriented to three principal axes. The polycrystal EPR spectra have been measured at room temperature and 77K, respectively.and the parameters of these spectra are given (g∥= 2. 094, g⊥= 2. 425, D= 0. 37 cm-1,E=0). The parameter of the isotropic magnetic exchange interaction J=-254cm-1 is determined, and that of the anisotropic magnetic exchange J1=-153 cm-1 is calculated. The average magnetic susceptibility of the polycrystal sample χ= 1. 39 ×10-6 (c. g. s) has been measured by Faraday powder method. Thus the average magnetic mornent μ=1. 43 B. M. can be calculated. It is shown that the exchange interactions between the metal ions of the binuclear copper(Ⅱ) cluster compound are confirmed antiferromagnetic In nature.

Vertical Structure of the Tidal Currents on the Continental Shelf of the East China Sea

The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current Harmonic Analysis results demonstrated that semi-diurnal tides dominated the current movement. The tidal currents of the principal diurnal and semidiurnal rotated clockwise with depth, with the deflection of the major semi-axes to the right in the upper layer and to the left in the lower layer. The vertical structures of two principal semi-diurnal constituents-M2 and S2-were similar, which indicates that the tidal currents are mainly barotropic in this area. The main features of the variation of the four principal tidal constituents with depth demonstrate that the currents in this region are influenced by the upper and lower boundary layers. Therefore, the tidal constituents of the shallow water are similar. Different vertical modes were calculated based on the Empirical Orthogonal Function (EOF) analysis of the Eastern and Northern components of the tidal currents, with a variance contribution for the zero-order model of at least 90%. The variance contribution of the baroclinic model is minimal, which further reveals a strong barotropic character for the tidal currents of this region.

Light Front Boson Model Propagation

The scope and aim of this work is to describe the two-body interaction mediated by a particle （either the scalar or the gauge boson） within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x＋ = 0 to x＋ 〉 0. It corresponds to the definition of the time ordering operation in the light front time x＋. We calculate the light-front Green＇s function for 2 interacting bosons propagating forward in x＋. We also show how to write down the light front Green＇s function from the Feynman propagator and finally make a generalization to N bosons.

Asymptotic Direct System of C^(*)-algebras and Locally AF-algebra

We define the direct limit of the asymptotic direct system of C^(*)-algebras and give some properties of it.Finally,we prove that a C^(*)-algebra is a locally AF-algebra,if and only if it is the direct limit of an asymptotic direct system of finite-dimensional C^(*)-algebras.

A new proof for the correctness of the F5 algorithm

In 2002, Faugere presented the famous F5 algorithm for computing GrSbner basis where two cri- teria, syzygy criterion and rewritten criterion, were proposed to avoid redundant computations. He proved the correctness of the syzygy criterion, but the proof for the correctness of the rewritten criterion was left. Since then, F5 has been studied extensively. Some proofs for the correctness of F5 were proposed, but these proofs are valid only under some extra assumptions. In this paper, we give a proof for the correctness of F5B, an equivalent version of F5 in Buchberger＇s style. The proof is valid for both homogeneous and non-homogeneous polynomial systems. Since this proof does not depend on the computing order of the S-pairs, any strategy of selecting S-pairs could be used in F5B or F5. Furthermore, we propose a natural and non-incremental variant of F5 where two revised criteria can be used to remove almost all redundant S-pairs.

Correlation between the molecular structure and transcis isomerization characteristics of azobenzenes

Photochemical and thermal isomerization of various azobenzenes was systematically investigated to understand the correlation between the molecular structure and trans → cis isomerization characteristics of azobenzenes. A blue shift in π-π absorption band of ortho-alkylated azobenzenes （1o and 2o） was observed together with a reduction in molar extinction coefficient （e） in comparison with both meta-alkylated azobenzenes （4m and 5m） and 7p lacking the meta and ortho substituents. For orthoalkylated azobenzene, photochemical trans-to-cis isomerization and thermal back cis-to-trans isomerization in solution oc- curred slowly when compared with 4m, 5m and 7p. The half-life time of the cis form of 20 was found to be 380 h, which is about 8-50 times longer than those of comparable 4m, 5m （43-13 h） and 7p （7 h）. Furthermore, comparison of the molecular structure and isomerization characteristics of azobenzene thiol （20 and 5m） self-assembled monolayers on flat gold surfaces indicates that the trans-to-cis photoconversion in monolayer systems is influenced by steric hindrance and strong intermoleculax interaction between azobenzene units.