Influences of clock resolution of bandwidth measurement on packet pair algorithm

Influences of the clock resolution of bandwidth estimator on the accuracy and stability of the packet pair algorithm was analyzed. A mathematic model has been established to reveal the relationship between the result deviation coefficient and the packet size, clock resolution and real bandwidth（value）of the measured route. A bandwidth self-adapting packet pair algorithm was presented based on the mathematic model to reduce the estimation error resulting from the clock resolution and to improve the accuracy and stability of measurement by adjusting the deviation coefficient. Experimental results have verified the validity and stability of the algorithm.     

Formalization of a New Approach Fault Analysis and of Fault Detection

Substitution permutation network （SPN） is one important structure of block cipher cryptosystems. Pri or work has shown different fault analyses on SPN. The formalization of fault analysis of both attack and protect on SPN have been given. The overhead and time tolerance of fault detection have been discussed. The pseudoblinding method to detect fault attack is introduced, and the balance of the security, overhead and time tolerance based on the evaluation could be made.     

Theoretical Analysis of the Solidification of Aluminum Alloy Billet in Air-Slip DC Mold

Based on the heat transfer analysis of Air-Slip DC mold, a numerical model was presented to study the quantitative relationships between critical solidification layer and casting rate, pouring temperature and mold cooling ability etc. The analytical results show that the Air-Slip mold heat transfer condition plays important roles on choices of a casting rate and the pouring temperature, and that the product of billet diameter and casting rate is a certain constant under a certain condition of the mold.     

Dynamic Analysis of the Biped Ice-skater Robot of Passive Wheel Type

A new passive wheel type of biped ice-skater robot （BISR） subjected to nonholonomic constraints was presented on the basis of ice-skating principle. Its motion principle and construction were discussed. After the model was simplified and the coordinate systems were established, the motion differential equations of the robot were obtained with the generalized Lagrange-Maggi equation when the nonholonomic constraints existed. Actual examples were given and the result was simulated on computer.     

Attribute-based signature on lattices

Attribute-based signature is a versatile class of digital signatures. In attribute-based signature, a signer obtains his private key corresponding to the set of his attributes from a trusted authority, and then he can sign a message with any predicate that is satisfied by his attributes set. Unfortunately, there does not exist an attribute- based signature which is resistance to the quantum attacks. This means we do not have secure attribute-based signature schemes in a post-quantum world. Based on this consideration, an attribute-based signature on lattices, which could resist quantum attacks, is proposed. This scheme employs ＂bonsai tree＂ techniques, and could be proved secure under the hardness assumption of small integer solution problem.     

Study on the toxic effect of the mixture of organophosphorus pesticide on perinatal rats

Objective To observe the toxic effect of the mixture of organophosphorus pesticide （MOP） on maternal rats and on the growth and development of their offspring. Methods Totally 40 Sprague-Dawley pregnant rats were randomly divided into three MOP dose groups and one control to which their offspring would be assigned, The experimental dosage of MOP and distilled water were administered orally starting on gestation day 15 and continued for 35 days. The physical development indices and the learning ability of F1 rats were measured during lactation. The pathological changes of uterus and liver of F0 rats were observed after weaning, while the weight ratio of uterus and some viscera to body of the F1 were examined. Results There were obvious changes of uterus and liver in the high-dose group of F0. The body-weight accretion of the F1 in high-dose group was obviously lower than that in control group （P〈0.05）. Some of the MOP F1 rats development indices delayed significantly （P〈 0. 05）, the learning ability decreased obviously, and the time of setting up memory prolonged （P〈0.05）. The ratio of the uterus weight to bodyweight in the F1 MOP groups was significantly higher than that in control group （P〈0. 05）. Oonclusion The experiment doses of MOP are proved to have significant reproductive toxicity on perinatai rats.     

Fault reconfiguration of shipboard power system based on triple quantum differential evolution algorithm

Fault reconfiguration of shipboard power system is viewed as a typical nonlinear and multi-objective combinatorial optimization problem. A comprehensive reconfiguration model is presented in this paper, in which the restored loads, switch frequency and generator efficiency are taken into account. In this model, analytic hierarchy process(AHP) is proposed to determine the coefficients of these objective functions. Meanwhile, a quantum differential evolution algorithm with triple quantum bit code is proposed. This algorithm aiming at the characteristics of shipboard power system is different from the normal quantum bit representation. The individual polymorphic expression is realized, and the convergence performance can be further enhanced in combination with the global parallel search capacity of differential evolution algorithm and the superposition properties of quantum theory. The local optimum can be avoided by dynamic rotation gate. The validity of algorithm and model is verified by the simulation examples.     

Repair and Strengthening Assessment of Existing Bridges Based on Time-Dependent Reliability Analysis

The strategy on repair and strengthening of existing bridges based on time-dependent reliability was analyzed with the maximum expected benefit as the objective function. A sample of risk-ranking decision was illustrated based on updated inspection information with 35 survival age. The effect of improvement of live loads and difference of repair methods on time-dependent reliability of existing bridges are considered. The results show that the decision method can be used in real project, with the cost of failure consequence and the risk of failure considered.     

Weighted Approximation of Kantorovich-Type Operator of Butzer-Hahn

A kind of Kantorovich-type operator of Butzer-Hahn Bn^* (f; x) on the bounded and integrable function space was introduced, and the properties of Bn^* (f; x) were studied. Positive theorem, converse theorem, and the order of weighted approximation of Bn^* (f; x) were obtained.     

Full waveform inversion method for horizontally inhomogeneous stratified media

Full waveform inversion method is an approach to grasp the physical property parameters of underground media in geotechnical nondestructive detection and testing field. Using finite-difference time domain （FDTD） method for elastic wave equations, the full-wave field in horizontally inhomogeneous stratified media for elastic wave logging was calculated. A numerical 2D model with three layers was computed for elastic wave propagation in horizontally inhomogeneous media. The full waveform inversion method was verified to be feasible for evaluating elastic parameters in lateral inhomogeneous stratified media and showed well accuracy and conver- gence. It was shown that the time cost of inversion had certain dependence on the choice of starting initial model. Furthermore, this method was used in the detection of nonuniform grouting in the construction of immersed tube tunnel. The distribution of nonuniform grouting was clearly evaluated by the S-wave velocity profile of grouted mortar base below the tunnel floor.     

Supersymmetry of In-group and “Out-group” Particles and Some Strange Phenomena

Introduction Afamilyofnewparticles[1],whichcannotbe admittedbythethreeknowngenerationsoffermions andwerenamed“out group”particles[2],wasput forwardbytheauthorusingJiao GongsubquarkmodelandtheimprovedPreonmodelintheearly1990s.“Out group”particlescanbec…     

Research on geological structure inversion method with acoustic computed tomography and borehole data

This article firstly proposes two problems related to geological structure inversion with acoustic computed tomography (CT): ① the results surveyed are different from true stratum layers; ② the existing acoustic CT inversion methods are based on wave’s travel route and velocity analysis, which is short of comprehensive analysis of the revealed geological data. Then, it puts forward the method of applying the borehole data to revise acoustic CT investigation result through controlling the boundary velocity. This method comprehensively uses acoustic data and borehole data to invert the rock masses’ shear wave speed. Comparing to calculating the rock mass’ wave speed with acoustic data alone, it makes full use of the information, and the results obtained are closer to real stratum. Finally, it applies the method to engineering project and the results gotten with the method are more accurate, which shows the reliability and accuracy of the method.     

Numerical Simulation Research on Laser Shock Forming of Thin Metal Sheet

Laser shock forming (LSF) of sheet metal is a new technique realized by applying an impulsive pressure generated by laser-induced shock wave on the surface of metal sheet.LSF of brass sheet metal was investigated using a Q-switched Nd:YAG laser with an energy per pulse of 15～50 joules.ABAQUS software was used to simulate laser shock forming process.The central displacement of the shocked region is measured and compared with the simulation.The higher pulse energy, the higher central displacement of the shocked region were obtained.The deformation of the simulation matches the experiment quite well.     

Numerical study of wave loads on a caisson-pile-deck composite structure over permeability seabed

To get the accurate wave loads on wharf composite structure, the wave force on small-scale piles and the uplift force on lower surface of caisson must be considered. Based on the Reynolds averaged Navier-Stokes (RANS) equations, the pore media theory and the volume of fluid (VoF) method, a three-dimensional numerical model is established. The model has been developed to simulate wave interaction with a composite structure including caisson, piles and deck. The numerical results agree very well with the experimental data on total force. The spatial distributions of the non-dimensional wave height and the maximum of wave pressure on surface of composite structure are presented and discussed. The effects of relative caisson length, relative wave height and relative caisson height on horizontal wave force are given. The result indicates that the horizontal wave force achieves maximum value at the relative caisson length of 0.18 and increases linearly with the increase of the relative caisson and wave height. It is proved that the model is an accurate and efficient numerical tool to investigate different problems of wave-structure interaction.     

配电网谐波的产生及治理措施

分析了配电网谐波产生的原因,指出随着现代工业的发展,大量换流设备不对称负荷等非线性用电设备在配电中的应用,这些负荷产生大量谐波注入电网,造成电压波形畸变,电能质量下降。此外当配网无功补偿电容器选择不当时,还会引起谐波放大,造成更严重的后果,因此应采取措施治理。     

星载激光脉冲水下光斑分布的研究

利用半解析Monte Carlo方法.计算了星载激光脉冲水下光斑的分布状况.采用修正Heny-ev-Greenstein函数表示大气和海水信道的散射相位函数.计算结果表明:水下光斑的大小与卫星高度、水下深度及大气、海水的散射强度有关;在不考虑卫星与地球相对移动的条件下,水下300 m深度光斑半径可达6 km;发射机所发射光子仅有84%～88%能够到达水下接收平面;星载激光水下光斑分布不能视为大气和海水各自散射所引起光斑分布的简单叠加.     

Research on Morlet Wavelet Based Lamb Wave Spatial Sampling Signal Optimization Method

In recent years, Lamb wave and piezoelectric transducers (PZTs) array based wavenumber filtering technique for damage estimation has been gradually studied. Compared with the time domain and frequency domain analysis of the Lamb wave signals, the wavenumber domain analysis is an effective approach to distinguish wave propagating direction and wave modes. However, the spatial resolution sampled by the PZTs is lower than that sampled by scanning laser Doppler vibrometer. As for the diameter of the PZT, it cannot be very small. In this paper, a new Lamb wave spatial sampling signal optimization method based on Morlet wavelet is proposed. Firstly, the frequency band parameter of the Morlet mother wavelet function is calculated by the Lamb wave excitation signal. Then, the sum of squared errors between the Lamb wave spatial sampling signal and the Morlet wavelet function fitting waveform at each scale factor and time factor is calculated. Finally, the scale factor and time factor corresponding to the least sum of squared errors can be judged to be the best match scale factor and time factor respectively, and the Morlet wavelet function fitting waveform in that scale factor and time factor can be seen as the optimized Lamb wave spatial sampling signal. The validation experiment performed on a glass fiber epoxy composite plate shows that the proposed method can improve the spatial resolution and length of the Lamb wave spatial sampling signal, and the sum of squared errors of this method is no more than 0.2.     

增强型绿色荧光蛋白标记的Hela细胞株的建立

目的构建增强型绿色荧光蛋白(EGFP)标记的Hela细胞系。方法PCR和DNA测序鉴定pEGFP-C1真核表达质粒,采用Qiagen tip 500进行pEGFP-C1真核表达质粒DNA的提取和纯化;cellfectin转染Hela细胞,G418筛选,有限稀释法单克隆培养,荧光显微镜进行荧光检测EGFP的表达,采用激光共聚焦显微镜观测器检测荧光特性。结果PCR和DNA测序证实pEGFP质粒结构正确;在倒置荧光显微镜下,转染24h后,部分Hela细胞可见绿色荧光,转染72h时,大约80%Hela细胞内均可见绿色荧光。加入含G418的选择性培养基进行选择性培养,选择荧光较强的Hela细胞经有限稀释,持续筛选及克隆化培养,获得稳定表达绿色荧光的Hela细胞克隆,扩大培养并传至10代以上,将此细胞株命名为Hela-EGFP。激光共聚焦显微镜观察发现:在蓝光(-395nm)激发时,Hela-EGFP细胞绿色荧光激发波长为395nm,最大发射峰为509nm。结论Hela-EGFP细胞株具备稳定表达EGFP的能力,为实时可视化进行宫颈癌侵袭转移机制的研究奠定了基础。     

Forecasting of stock returns by using manifold wavelet support vector machine

An admissible manifold wavelet kernel is proposed to construct manifold wavelet support vector machine(MWSVM) for stock returns forecasting.The manifold wavelet kernel is obtained by incorporating manifold theory into wavelet technique in support vector machine(SVM).Since manifold wavelet function can yield features that describe of the stock time series both at various locations and at varying time granularities,the MWSVM can approximate arbitrary nonlinear functions and forecast stock returns accurately.T...