The Organizational Structure Transformation Research of Chinese Aviation Enterprise

The research on Problems Chinese aviation enterprise face with,the detailed strategy of organizational structure change is putforwards,the method and model of performance evaluation on organizational structure change is described,and some possible patterns ofChinese organizational structure change are put forth. The conditions and step of implementation of flat organizational structure are re-searched.     

The conductance and polarization in quantum wires with Rashba and Dresselhaus spin-orbit interactions

The conductance and polarization are studied in one-dimensional ballistic quantum wire with both Rashba and Dresselhaus spin-orbit interactions.Two kinds of structures are considered in the present work,one with mixture of two interactions and the other with sequence structure of them.We find that the conductance and polarization are strongly affected by these two interactions.With both interactions we obtain a multi-peak contour of spin polarization and a dramatic oscillation pattern of spin conductance,which are due to the different combination of the two spin-orbit interactions.     

宽阻带小型化低通滤波器的设计

This paper presents a novel low-pass filter （LPF） with sharp rejection, wide stopband and compact size, which are realized by the defected ground structure （DGS） and the defected microstrip structure （DMS）. The equivalent circuit model is proposed and the circuit parameters are extracted by the circuit simulation software. The parameters measured are 3 dB cutoff frequency fc of 5.2 GHz, the insertion loss less than 0.5 dB from DC to 4.0 GHz and S21 less than -20 dB within the wide stopband from 6 GHz to 16 GHz. The results of the circuit optimization agree well with those of the full wave simulation and the measured ones, which validate the effectiveness of the equivalent circuit model. The size of the proposed LPF is decreased compared with normal LPF. This LPF can be applied in rectennas to eliminate high order harmonics.     

Fabrication of hierarchical polycaprolactone/gel scaffolds via combined 3D bioprinting and electrospinning for tissue engineering

It is a severe challenge to construct 3D scaf- folds which hold controllable pore structure and similar morphology of the natural extracellular matrix （ECM）. In this study, a compound technology is proposed by com- bining the 3D bioprinting and electrospinning process to fabricate 3D scaffolds, which are composed by orthogonal array gel microfibers in a grid-like arrangement and inter- calated by a nonwoven structure with randomly distributed polycaprolactone （PCL） nanofibers. Human adipose- derived stem cells （hASCs） are seeded on the hierarchical scaffold and cultured 21 d for in vitro study. The results of cells culturing show that the microfibers structure with controlled pores can allow the easy entrance of cells and the efficient diffusion of nutrients, and the nanofiber webs layered in the scaffold can significantly improve initial cell attachment and proliferation. The present work demon- strates that the hierarchical PCL/gel scaffolds consisting of controllable 3D architecture with interconnected pores and biomimetic nanofiber structures resembling the ECM can be designed and fabricated by the combination of 3D bioprinting and electrospinning to improve biological per- formance in tissue engineering applications.     

STUDY OF GROOVE NONRADIATIVE DIELECTRIC WAVEGUIDE AND LEAKYWAVE ANTENNA

A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcomes the difficulty of as-sembling precisely the dielectric strip in the nonradiative dielectric(NRD)structure.Thedispersion characteristics of the GNRD waveguide,and the propagation and radiationcharacteristics of the GNRD leakywave antcnna have been analysed by the use of thetransverse rcsonance mcthod.The theoretical results are in good agreement with the exper-imental data.     

Identification of novel catalytic features of endo-β-1,4-glucanase produced by mulberry longicorn beetle Apriona germari

Mulberry longicorn beetle, Apriona germari, has been reported to produce two endo-β-1,4-glucanases or AgEGases (accession Nos. Q6SS52 and Q5XQD1). AgEGase sequence contains catalytic motif (amino acid residues 37~48), which is the characteristic of family Glycohydrolase 45 and is identified as the substrate binding site. The application of bioinformatics ap-proaches includes sequence analysis, structural modeling and inhibitor docking to relate the structure and function of AgEGases. We have dissected the sequence and structure of AgEGase catalytic motif and compared it with crystal structure of Humicola insolens endoglucanases V. The results show an involvement of sulfur containing amino acid residues in the active site of the enzyme. Cys residues and position of disulfide bonds are highly conserved between the two structures of endoglucanases of A. germari. Surface calculation of AgEGase structure in the absence of Cys residues reveals greater accessibility of the catalytic site to the substrate involving Asp42, a highly conserved residue. For the inhibition study, tannin-based structure was docked into the catalytic site of AgEGase using ArgusLab 4.0 and it resulted in a stable complex formation. It is suggested that the inhibition could occur through formation of a stable transition state analog-enzyme complex with the tannin-based inhibitor, as observed with other insect cellulases in our laboratory.     

Estimation of Shallow S-Wave Velocity Structure of Two Practical Sites from Microtremors Array Observation in Tangshan Area

Microtremors array observation for estimating S-wave velocity structure from phase velocities of Rayleigh and Love wave on two practical sites in Tangshan area by a China-US joint group are researched.The phase velocities of Rayleigh wave are estimated from vertical component records and those of Love wave are estimated from three-component records of microtremors array using modified spatial auto-correlation method.Haskell matrix method is used in calculating Rayleigh and Love wave phase velocities,and the shallow S-wave velocity structure of two practical sites are estimated by means of a hybrid approach of Genetic Algorithm and Simplex.The results are compared with the PS logging data of the two sites,showing it is feasible to estimate the shallow S-wave velocity structure of practical site from the observation of microtremor array.     

Experimental Study of Structure Shock Vibration in Soil Caused by Explosion of Conventional Weapons

When hitting underground structures directly or exploding in rock-soil media near underground structures, the conventional weapons with large charge weight will make underground structures be subjected to strong shock vibration and cause personal casualty and damage of precision electronic equipments. The shock vibration has become one of the cardinal killing means of weapons. However, the existing methods of predicting structure shock vibration are limited evidently. In this paper the coupling coefficient of acceleration in clayey soil is obtained firstly. Subsequently based on repeated experiments of chemical explosion, after dimension analysis and by using method of multivariate stepwise regression, the calculation formulae of shock vibration acceleration for the underground structure are obtained finally. The formulae consider top and side explosion respectively, taking into account the effects of penetration depth, charge weight, distance to explosion center, rock-soil media, size of structure and buried depth. They are easy to use with high practicability and degree of confidence, and can provide credible evidence for prediction of shock vibration and vibration isolating design of underground structure.     

Influence of structure plane size on seismic response of soil-structure interaction

The influence of the change of structure plane size on seismic response was studied for a soil-structure interaction system. Based on the finite element method, a soil-structure interaction calculation model was established to analyze the seismic response by changing the structure plane size and choosing different earthquake waves for different soil fields. The results show that when the natural periods of vibration for different structure plane sizes are close, under the same earthquake wave, the total displacement on the top layer of the structure and the foundation rotation displacement decrease with the increase of structure plane size, and the proportion of superstructure elastic selfdeformation displacement to the total displacement increases with the increase of structure plane size. While for different types of sites and seismic waves, under the horizontal and vertical seismic waves, the seismic responses of different plane sizes have a similar change rule.     

A Network Framework Based on MechanicalComponent Design and Manufacturing

Network manufacturing has been rapidly developed and is going to play an important role in modern indusu‘y. The core of network manufacturing of mechanical products is the design and manufacturing based on the computer network technology. A network framework is introduced for manufacturing mechanical components at two main levels. On the design level features of the component are initially studied based on the structure and functions of the component. Details of the design procedure and contents are then analyzed with three main kinds of components. In this stage, selection of materials, calculation of sla‘ess and deflection under load, determination of the size are carried out using CAD. On the manufacturing level various aspects of CAPP are discussed, including the principle and the modes of positioning the component, the exerted clamping forces, cutting engagement and input parameters, machine tools used, and machining fluids if necessary. Finally a prototype of the network framework is presented with several pieces of data terminal equipment through a local area network, the topological structure, and data sharing and security, without concerning the use of the concurrent engineering techniques and virtual manufacturing, and virtual measuring techniques.     

支持向量分类算法在5-HT3受体拮抗剂的构效关系研究中的应用

In this work, support vector classification （SVC） algorithm was used to build structure-activity relationship （SAR） model of the 5-hydroxytryptamine type 3 （5-HT3 ） receptor antagonists with 26 compounds. In a benchmark test, SVC was compared with several techniques of machine learning currently used in the field. The prediction performance of the model was discussed on the basis of the leave-one-out cross-validation. The results show that the accuracy of prediction of SVC model was higher than those of back propagation artificial neural network （BP ANN）, K-nearest neighbor （KNN） and Fisher methods.     

SVC bitstream adaptation in MPEG-21 multimedia framework

INTRODUCTION Scalable video coding (SVC) (Schwarz et al., 2004) is the most promising video format for appli- cations of collaborative communication. First, SVC format, which is extended from the latest advanced video coding (AVC), is appropriate for creating a wide variety of bitrates with high compression effi- ciency. Second, an original SVC bitstream can be easily truncated in different ways to meet various characteristics and variations of devices and connec- tions. The scalabil…     

基于MATCONT的电力系统电压稳定分岔及控制仿真试验

介绍了电力系统ODE模型中引起电压失稳的常见分岔类型及分岔控制的基本概念;运用基于Matlab的数值分岔分析软件MATCONT对一个经典单机—动态负荷系统进行了分岔分析,验证了PQ动态负荷模型系统存在着鞍结分岔(SNB)现象,而RL动态负荷模型系统并无分岔现象产生.为延迟PQ动态负荷模型系统的鞍结分岔点,在原系统中引入了线性状态反馈控制和SVC控制两种分岔控制方法.MATCONT仿真结果显示,这两种控制方法均能够有效延迟鞍结分岔,从而提高系统的电压稳定性,并可通过选择合理的反馈控制器增益及SVC增益获得理想的分岔控制效果.     

RTP payload format for H.264/SVC scalable video coding

The scalable extension of H.264/AVC, known as scalable video coding or SVC, is currently the main focus of the Joint Video Team‘s work. In its present working draft, the higher level syntax of SVC follows the design principles of H.264/AVC.Self-contained network abstraction layer units (NAL units) form natural entities for packetization. The SVC specification is by no means finalized yet, but nevertheless the work towards an optimized RTP payload format has already started. RFC 3984, the RTP payload specification for H.264/AVC has been taken as a starting point, but it became quickly clear that the scalable features of SVC require adaptation in at least the areas of capability/operation point signaling and documentation of the extended NAL unit header. This paper first gives an overview of the history of scalable video coding, and then reviews the video coding layer (VCL)and NAL of the latest SVC draft specification. Finally, it discusses different aspects of the draft SVC RTP payload format, including the design criteria, use cases, signaling and payload structure.     

基于PSO-SVM的电动车铅酸蓄电池SOC预测

为了提高电动车铅酸蓄电池的电池荷电状态(SOC)预测精度,将粒子优化算法(PSO)引入到支持向量机(SVM)中,建立了PSO-SVM电动车铅酸蓄电池SOC预测模型,模型输入量为电池的电压和电流,输出量为SOC。采用PSO算法对SVM的惩罚因子C和径向基函数宽度σ寻优,降低了SVM参数取值的盲目性,提高了预测精度。设计了铅酸蓄电池数据智能采集系统,并进行了实际运行车辆电池数据采集。在advisor2002软件中获取的电池数据和实际车辆电池运行数据的基础上,进行了模型训练和预测。结果表明,PSO-SVM预测模型相对传统的BP、RBF和SVM预测模型具有更好的精度和推广能力,满足了"SOC估算精度小于5%"的要求,从而表明该模型是有效的、可行的,并具有较好的工程实用价值。     

Prediction of shelled shrimp weight by machine vision

The weight of shelled shrimp is an important parameter for grading process. The weight prediction of shelled shrimp by contour area is not accurate enough because of the ignorance of the shrimp thickness. In this paper, a multivariate prediction model containing area, perimeter, length, and width was established. A new calibration algorithm for extracting length of shelled shrimp was proposed, which contains binary image thinning, branch recognition and elimination, and length reconstruction, while its width was calculated during the process of length extracting. The model was further validated with another set of images from 30 shelled shrimps. For a comparison purpose, artificial neural network (ANN) was used for the shrimp weight predication. The ANN model resulted in a better prediction accuracy (with the average relative error at 2.67%), but took a tenfold increase in calculation time compared with the weight-area-perimeter (WAP) model (with the average relative error at 3.02%). We thus conclude that the WAP model is a better method for the prediction of the weight of shelled red shrimp.      

Trauma changes everything: Examining the relationship between adverse childhood experiences and serious,violent and chronic juvenile offenders

Among juvenile offenders, those who commit the greatest number and the most violent offenses are referred to as serious, violent, and chronic (SVC) offenders. However, current practices typically identify SVC offenders only after they have committed their prolific and costly offenses. While several studies have examined risk factors of SVCs, no screening tool has been developed to identify children at risk of SVC offending. This study aims to examine how effective the adverse childhood experiences index, a childhood trauma-based screening tool developed in the medical field, is at identifying children at higher risk of SVC offending. Data on the history of childhood trauma, abuse, neglect, criminal behavior, and other criminological risk factors for offending among 22,575 delinquent youth referred to the Florida Department of Juvenile Justice are analyzed, with results suggesting that each additional adverse experience a child experiences increases the risk of becoming a serious, violent, and chronic juvenile offender by 35, when controlling for other risk factors for criminal behavior. These findings suggest that the ACE score could be used by practitioners as a first-line screening tool to identify children at risk of SVC offending before significant downstream wreckage occurs.     

基于小波神经网络的污水厂总磷预测模型

污水厂进水污染物与出水总磷的变化规律呈高度非线性,而传统机理预测模型需要依据经验设定大量参数,预测精度较低,预测相对误差处于15%~25%之间。为提高预测精度,以进水化学需氧量、总氮、氨氮、总磷、进水量5个进水指标与出水总磷浓度的映射关系建立小波神经网络预测模型。结果表明,小波神经网络模型模拟相对误差为9.87%,相较于机理模型,预测误差降低了5%~15%;同时模型收敛速度快,具有强大的非线性拟合能力,运行稳定性强,对污水厂实际运行中出水总磷预测有一定参考作用。     

SVM颗粒运动形态及其能量耗散的预测分析

基于离散单元法建立了圆柱形颗粒阻尼器的仿真模型,研究了阻尼器内颗粒在不同激振条件下的运动形态及其能量耗散大小。为了获取两者之间的定量关系,应用基于网格搜索法(GS)的支持向量机(SVM)建立了颗粒运动形态的分类预测模型及其能量损耗的回归预测模型,对颗粒运动形态的分布及其能量损耗的大小进行了预测,并通过仿真进行了验证。结果表明:基于GS方法优化的SVM能够建立一个预测准确度很高、推广泛化能力很强的分类和回归预测模型,该预测模型不仅能够很好地揭示颗粒系统在不同运动形态下的能量耗散的变化规律,而且还能在较大的激振条件范围内确定系统能量耗散最大值及对应的运动形态。