在环形理想导体空腔中极向线电流产生的磁场

本文研究在环形理想导体空腔中极向线电流产生的磁场。在一级环形效应近似下得到的理论结果，基本上与实验数据一致，并且可以推广使用到具有一定类型极向电流分布的情况。

走向线在地质工作中的应用

在矿产勘查、矿床开采以及工程设计等工作中 ,都需要首先了解地表及地下深处岩层或矿层的分布 ,查明地质构造情况 ,利用走向线可以帮助我们间接测定岩层产状 ,编制倾斜岩层地质图 ,求岩层厚度、岩层埋藏深度。

利用伪辛几何中的迷向线构作结合方案与PBIB设计

设Fq是q元有限域，q是2的一个方幂。取Fq上2v＋δ（δ＝1或2）维伪辛空间中迷向线（≠＜e2v+1＞）构成的集合作为处理集，构作了一些结合方案和PBIB设计，并且计算了它们的参数。

锁边圆管带式输送机运转理论分析

在理论分析的基础上，介绍了锁边圆管带式输送机的工作原理、布置方式、带芯材料的选择、散料不会从下部流出等一系列特殊问题，同时分析了锁边器啮合力、凸凹曲线段的张力、阻力计算等，并给出了系统布置参数的确定方法．锁边圆管带式输送机可用于任意倾角的提升，它的运输能力远大于波纹挡边带横隔板带式输送机和夹带带式输送机．

单源点法的一种改进

在应用能量线性叠加计算港内不规则波绕射系数时[1 ,2 ] ,通过假设不同的计算点具有不同的方向谱 ,从而增加单源点法考虑地形变化的能力。其中各计算点的方向谱由逆波向线追踪方向确定。本文由此观点建立数学模型 ,并通过实例计算 。

A High Breakdown Voltage Thin SOI Device with a Vertically Linearly Graded Concentration Drift Region

As the thickness of an SOI layer varies,a minimum breakdown voltage is reached when the thickness is about 2μm. The vertical electric field of the SOI LDMOS with a drift region which is vertically linearly graded is constant. The vertically linearly graded concentration drift can be achieved by impurity implanting followed by thermal diffusion. In this way,the vertical breakdown voltage of SOI LDMOS with 2μm thickness SOI layer can be improved by 43%. The on-state resistance is lowered by 24 % because of the higher impurity concentration of the SOI surface.

NEW PRINCIPLE FOR DIRECTIONAL COMPARISON CARRIER PROTECTION OF EHV TRANSMISSION LINES

The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave channels is the most suitable protection scheme for long distance EHV transmission lines and is widely used in power systems.The key element of such protection is a directional relay used to discriminate the fault direction.In order to overcome the disadvantages of conventional directional relays,the authors of this paper put forward the directional comparison carrier protection based on the artificial neural network(ANN).The protection is extensively tested using electromagnetic transient program (EMTP) under various electric power system operating and fault conditions.It is proved that the directional comparison carrier protection based on ANN,which can recognize various fault patterns of the protected transmission line(such as fault direction,fault phases etc.)correctly in any kind of operating and fault conditions and the whole process,is satisfactory for EHV transmission line protection.

Orientation of Pigments in the Isolated PhotosystemⅡSub-core Reaction Center CP47/D1/D2/Cyt b-559 Complexes:A Linear Dichroism Study

Linear dichroism (LD) spectroscopy is an important technique in the study of the orientation and organization of pigments in the photosynthetic membrane complexes in vivo and in vitro . In this work, the orientation of the pigments in the isolated photosystem Ⅱ (PSⅡ) sub_core reaction center complexes was analyzed and characterized by means of low temperature absorption and LD spectroscopy. The preparations containing different amounts of CP47 isolated from spinach (Spinacia oleracea L.) chloroplast were used in order to investigate the orientation of pigments in the PSⅡ sub_core CP47/D1/D2/Cyt b_559 (CP47/D1/D2) complexes. Chlorophyll a (Chl a) absorbing at 680 nm in CP47/D1/D2/Cyt b_559 complex showed an orientation of the Q y transition parallel to the membrane plane. It is proposed that there are two forms of β_carotene (β_Car) in CP47/D1/D2/Cyt b_559 complex, denoted as β_Car (Ⅰ) and β_Car (Ⅱ), with different orientations, β_Car (Ⅰ) at 470 and 505 nm is roughly parallel to the membrane plane, and β_Car (Ⅱ) at 460 and 490 nm seems to be perpendicular orientation. Upon the photoinhibitory experiment β_Car (Ⅱ) was found to be photosensitive and easily photodamaged. It also showed that the positive LD signal observed at 680 nm was quite complicated. This signal is tentatively attributed to P680 and some Chl a of antenna in CP47 protein based upon our measurements.

DIMENSIONALITY REDUCTION BASED ON SVM AND LDA,AND ITS APPLICATION TO CLASSIFICATION TECHNIQUE

Some dimensionality reduction （DR） approaches based on support vector machine （SVM） are proposed. But the acquirement of the projection matrix in these approaches only considers the between-class margin based on SVM while ignoring the within-class information in data. This paper presents a new DR approach, call- ed the dimensionality reduction based on SVM and LDA （DRSL）. DRSL considers the between-class margins from SVM and LDA, and the within-class compactness from LDA to obtain the projection matrix. As a result, DRSL can realize the combination of the between-class and within-class information and fit the between-class and within-class structures in data. Hence, the obtained projection matrix increases the generalization ability of subsequent classification techniques. Experiments applied to classification techniques show the effectiveness of the proposed method.

An adaptive noise attenuation method for edge and amplitude preservation

Noise intensity distributed in seismic data varies with different frequencies or frequency bands; thus, noise attenuation on the full-frequency band affects the dynamic properties of the seismic reflection signal and the subsequent seismic data interpretation, reservoir description, hydrocarbon detection, etc. Hence, we propose an adaptive noise attenuation method for edge and amplitude preservation, wherein the wavelet packet transform is used to decompose the full-band seismic signal into multiband data and then process these data using nonlinear anisotropic dip-oriented edge-preserving fi ltering. In the fi ltering, the calculated diffusion tensor from the structure tensor can be exploited to establish the direction of smoothing. In addition, the fault confidence measure and discontinuity operator can be used to preserve the structural and stratigraphic discontinuities and edges, and the decorrelation criteria can be used to establish the number of iterations. These parameters can minimize the intervention and subjectivity of the interpreter, and simplify the application of the proposed method. We applied the proposed method to synthetic and real 3D marine seismic data. We found that the proposed method could be used to attenuate noise in seismic data while preserving the effective discontinuity information and amplitude characteristics in seismic refl ection waves, providing high-quality data for interpretation and analysis such as high-resolution processing, attribute analysis, and inversion.

Effect of crystal orientation on tensile mechanical properties of single-crystal tungsten nanowire

Based on the high-purity single-crystal tungsten nanowire firstly prepared by the metal-catalyzed vapor-phase reaction method, molecular dynamics method was used to calculate tensile stress-strain curves and simulate microscopic deformation structures of the single-crystal tungsten nanowires with different crystal orientations of 〈100〉, 〈110〉and 〈111〉, in order to reveal the effect of crystal orientation on their tensile mechanical properties and failure mechanisms. Research results show that all of the stress-strain curves are classified into four stages： elastic stage, damage stage, yielding stage and failure stage, where 〈100〉orientation has a special hardening stage after yielding and two descending stages. The crystal orientation has little effect on elastic modulus but great effect on tensile strength, yielding strength and ductility, depending on different atomic surface energies and principal sliding planes. The calculated values of elastic modulus are in good agreement with the tested values of elastic modulus.

TRANSVERSE VELOCITY ESTIMATION BASED ON HIGH-ORDER DOPPLER EFFECT OF MOVING OBJECT

The one-order phase of the echo changes if there is relative radial moving between the object and the radar, i.e. , the Doppler effect. The Doppler effect is widely used in radar signal processing. The transverse motion of the object cannot change the one-order phase of the echo, but the high-order phase. The high-order Doppler effect of the transverse moving target is presented and a new algorithm for obtaining the transverse velocity is given. The scalar velocity of a target moving steadily in any direction can be calculated with one-order and two-order items of the echo phase. The calculating method and simulating results are given. As the transverse speed is 900 km/h, the speed calculation error is less than 0. 06% if SNR of echo signal is higher than 0 dB.

Vector Correlations and Product Rotational Alignments of Reactions Ca+RBr→CaBr+R(R=CH_(3),C_(2) H_(5) and n-C_(3) H_(7))

The quasiclassical trajectory method is used to study the vector correlations of the reactions Ca＋RBr （R=CH3, C2H5 and n-C3H7Br） and the rotational alignment of product CaBr. The product rotational alignment parameters at different collision energies and the vector correlations between the reagent and product are numerically calculated. The vector correlations are described by using the angle distribution functions P（θr）, P（φr）, P（θr, φr） and the polarization-dependent differential cross sections （PDDCSs）. The peak values of P（θr） of the product CaBr from Ca＋CH3Br are larger than those from Ca＋C2H5Br and Ca＋n-C3H7Br. The peak of P（θr） at φr= 3π/2 is apparently stronger than that at φr= x/2 for the three reactions Ca＋RBr. The calculation results show that the rotational angular momentum of the product CaBr is not only aligned, but also oriented along the direction which is perpendicular to the scattering plane.The product CaBr molecules are strongly scattered forward. The orientation and alignment of the product angular momentum will affect the scattering direction of the product molecules to varying degrees.

Construction and solution of strain model along thickness of aluminum alloy plate under plastic deformation

A thickness strain model of aluminium alloy plate under plastic deformation,based on thin plate assumption was proposed.It is found that when ratio of stress fractions is constant during in-plane loading,ratios of strain components under various loading conditions are linearly related and these points of ratios form a η-η line.Under these simple loadings,strains in thickness direction can be easily calculated by the η-η line equation without integral and differential work.When the plate is under more complicated loading conditions,the thickness can be computed by the proposed optimization and piecewise calculation model.Validation computations indicate that the relative error of the results of the presented model is less than 0.75% compared with the proven theories and FE simulation.Therefore,the developed model can be applied to engineering calculation,e.g.pre-stretching analysis of aerospace aluminium thick plate,with acceptable accuracy.

The FDTD Full Wave Analysis of Fractal Antennas

The full wave FDTD method was used to analyze the Hilbert and H fractal curves antennas. The computational results of the input impedance of Hilbert fractal antenna are in good agreement with the experiments in the documents. The results also show that the self-similarity of the fractal structure leads to the multiplicity of resonances over some predetermined operating bandwidths of the antenna. Fractal geometries of Hilbert and H curves can be implemented to miniaturize the antenna, too. The results also show that the higher order fractal antenna leads to the more efficient reduction of the antenna size than the lower order one. Furthermore, the far field patterns remain almost the same as those of the dipole at their own resonant frequencies.

Analysis of mechanical performance of braided esophageal stent structure and its wires

This paper aims to find the relationship between the structural parameters and the radial stiffness of the braided stent and to understand the stress distribution law of the wires. According to the equation of the space spiral curve, a three-dimensional parametrical geometrical model is constructed. The finite element model is built by using the beam-beam contact elements and 3D beam elements. The constituent nitinol wires are assumed to be linear elastic material. The finite element analysis figures out that the radial stiffness of the stent and the stress distribution of the wires are influenced by all the structural parameters. The helix pitch of the wires is the most important factor. Under the condition of the same load and other structural parameters remaining unchanged, when the number of wires is 24, the stress of the wire crosssection is at the minimum. A comparison between the vitro experimental results and the analytical results is conducted, and the data is consistent, which proves that the current finite element model can be used to appropriately predict the mechanical performance of the braided esophageal stents.

Support vector machine for prediction of siRNA silencing efficacy

In order to assist the design of short interfering ribonucleic acids （siRNA）, 573 non-redundant siRNAs were collected from published literatures and the relationship between siRNAs sequences and RNA interference （RNAi） effect is analyzed by a support vector machine （SVM） based algorithm relied on a basebase correlation （BBC） feature. The results show that the proposed algorithm has the highest area under curve （AUC） value （0. 73） of the receive operating characteristic （ROC） curve and the greatest r value （0. 43） of the Pearson＇s correlation coefficient. This indicates that the proposed algorithm is better than the published algorithms on the collected datasets and that more attention should be paid to the base-base correlation information in future siRNA design.

漏电保护器的选择及使用

合格的漏电保护器如果得不到正确、合理的使用和正确的保养维修,是很难实现其安全作用的。因此,要正确掌握保护器的选型、安装和使用方法,使之在安全工作中发挥更大作用。

Screening for genetic loci affecting the active zone formation in C. elegans

Objective To screen and identify genetic loci affecting the active zone formation in C. elegans. Methods A SYD-2：：GFP reporter was constructed and used as an active zone marker for forward genetic screen to identify genetic loci affecting the active zone formation. Results Eight isolated mutant alleles were characterized from 15,000 haploid genomes. The SYD-2：：GFP phenotypes of these mutants are mainly reflected as the changes of number, morphology, distribution of puncta and the gaps appearance. Some mutants also exhibit visible behavioral or physical phenotypes, and aldicarb resistant or sensitive phenotypes. Conclusion These mutants provide the opportunity for further systematic research on the active zone formation and the neurotransmission.

The Convergence Characteristic of the Forward I-V Characteristic Curves of a Semiconductor Silicon Barrier at Different Temperatures

The /-V-（T） characteristic curves of p-n junctions with the forward voltage as the independent variable, the logarithm of forward current as the dependent variable, and the junction temperature as the parameter, almost converge at one point in the first quadrant. The voltage corresponding with the convergence point nearly equals the bandgap of the semiconductor material. This convergence point can be used to obtain the I-V characteristic curve at any temperature.