Memory based scheme to monitor non-random small shift patterns in manufacturing process

Consistent high-quality and defect-free production is the demand of the day. The product recall not only increases engineering and manufacturing cost but also affects the quality and the reliability of the product in the eye of users. The monitoring and improvement of a manufacturing process are the strength of statistical process control. In this article we propose a process monitoring memory-based scheme for continuous data under the assumption of normality to detect small non-random shift patterns in any manufacturing or service process.The control limits for the proposed scheme are constructed. The in-control and out-of-control average run length(AVL) expressions have been derived for the performance evaluation of the proposed scheme. Robustness to non-normality has been tested after simulation study of the run length distribution of the proposed scheme, and the comparisons with Shewhart and exponentially weighted moving average(EWMA) schemes are presented for various gamma and t-distributions. The proposed scheme is effective and attractive as it has one design parameter which differentiates it from the traditional schemes. Finally, some suggestions and recommendations are made for the future work.     

Surge Response of a Compliant Offshore Structure by Time Domain Simulation

A single-degree-of-freedom equation of motion was used for modeling a compliant offshore structure exposed to viscous hydrodynamic loads. The equation of motion contains nonlinearities in the forms of both Duffing stiffness and Morison drag force with current. The water particle velocity and acceleration for calculating the Morison inertia and drag forces are modeled as Gaussian processes based on a Pierson-Moskowitz (P-M) elevation spectrum. The single-degree-of-freedom equation of motion containing different ocean current values are then numerically integrated via a fourth-order Runge-Kutta scheme. Time trajectories of the surge response displacements of the offshore structure and the response probability density curves are obtained. Furthermore, the ocean current influences on the response central moments up to the fourth order are studied. A literature review reveals that this is the first treatment of such a pair of nonlinearities in time domain. The simulation results are analyzed, and some conclusions valuable for engineering design are pointed out.     

Equivalent Bar Conceptions for Computer Analysis of Pantographic Foldable Structures

An equivalent bar conception is firstly developed for the computer analysis of pantographic foldable structures. The uniplet of two three-node beam elements is assumed as a six-bar assembly with respect to least norm least square solution for the elastic strain energy equality. The equilibrium equation is developed for the equivalent models, and the internal forces formulated sequently for backup calculation. This procedure is proved practical for some engineering, and some interesting concepts proposed. Finally, three numerical tests are presented.     

Local Search Algorithm with Hybrid Neighborhood and Its Application to Job Shop Scheduling Problem

A new local search method with hybrid neighborhood for Job shop scheduling problem is developed. The proposed hybrid neighborhood is not only efficient in local search, but also can help overcome entrapments while search procedure get trapped at local optima and carry the search to areas of the feasible set with better prospect. New strategies used for breaking out of entrapments are presented and they are helpful for the procedure to improve local optima. A performance comparison of the proposed method with some best-performing algorithms on all 10-job, 10-machine benchmark problems and the other two problems generated by Fisher and Thompson ( ie. , FT6 and FT20) is made. The experiment results show the better optimal performance of the proposed algorithm.     

The Application of RFID Technologies in Construction

RFID technologies have advanced greatly and deployed successfully in many industry sectors in recent years. Construction industry could benefit from the applications of RFID technologies but as yet has not found sufficient application areas. This project gives a comprehensive awareness of the RFID technologies, which focus on the investigation on the UK construction industry. The current status of RFID in construction and its potentials are specified in the analysis of questionnaires and case studies. Finally, basing on the investigations, some further tasks in developing RFID technologies are carried, including some recommendations, for the construction industry.     

Wavelet moment invariants extraction of underwater laser vision image

Wavelet moment invariants are constructed for object recognition based on the global feature and local feature of target, which are brought for the simple background of the underwater objects, complex structure, similar form etc. These invariant features realize the multi-dimension feature extraction of local topology and invariant transform. Considering translation and scale invariant characteristics were ignored by conventional wavelet moments, some improvements were done in this paper. The cubic B-spline wavelets which are optimally localized in space-frequency and close to the forms of Li＇s （or Zernike＇s） polynomial moments were applied for calculating the wavelet moments. To testify superiority of the wavelet moments mentioned in this paper, generalized regression neural network （GRNN） was used to calculate the recognition rates based on wavelet invariant moments and conventional invariant moments respectively. Wavelet moments obtained 100% recognition rate for every object and the conventional moments obtained less classification rate. The result shows that wavelet moment has the ability to identify many types of objects and is suitable for laser image recognition.     

Ideals of Classical Linear Lie Superalgebra P（n） over Commutative Rings

Let R be a commutative ring with identity 1. The relations between the ideals of Lie superalgebra P(n) and the ideals of R are discussed by studying the basis, center and order ideal of P(n). All ideals of P(n) are proved to be minimal and standard.     

Free-Surface Wave Interaction with a Very Large Floating Structure

The free-surface wave interaction with a pontoon-type very large floating structure（VLFS） is analyzed by utilizing a modal expansion method. The modal expansion method consists of separating the hydrodynamic analysis and the dynamic response analysis of the structure. In the dynamic response analysis of the structure,the deflection of the structure with various edge conditions is decomposed into vibration modes that can be arbitrarily chosen. Free-free beam model, pinned-free beam model and fixed-free beam model are three different types of edge conditions considered in this study. For each of these beam models, the detailed mathematical formulations for calculating the corresponding eigenvalues and eigenmodes have been given, and the mathematical formulations corresponding to the beam models of pinned-free beam and fixed-free beam are novel. For the hydrodynamic analysis of the structure, the boundary value problem（BVP） equations in terms of plate modes have been established, and the BVP equations corresponding to the beam models of pinned-free beam and fixedfree beam are also novel. When these BVP equations are solved numerically, the structure deflections and the wave reflection and transmission coefficients can be obtained. These calculation results point out some findings valuable for engineering design.     

An Active Endoscopy Robotic System for Direct Tracheal Inspection

The development of active endoscopy techniques is one important area of medical robot.This paper designed a new flexible and active endoscopy robotic system for direct tracheal inspection.The mobile mechanism of the robot is based on the inchworm movement actuated by pneumatic rubber actuator.There are five air chambers controlled independently,by adjusting pressures in air chambers,the robot can move in a straight mode or in a bending mode.The inspection sensors and some therapy surgery tools can be equipped in the front of the robot.The prototype was made and its mechanical characteristics were analyzed.The robot could move smoothly in a small plastic tube,and the robot is respectable to be used for inspection in human trachea directly.     

Analysis on the Irregular and Asymmetrical Power／Ground Structure by PEEC Modeling

In order to provide some reference for the design of the power/ground system, a complicated power/ground sys, tem in time and frequency domains was analyzed, which is based on PEEC (Partial Element Equivalent Circuit). According to tlhe actual requirements, characteristics of some common power/ground structures in time and frequency domains, such as SSN (Simultaneous Switching Noise), are obtained for the future research. The results show the first resonance point is changed with the structure of the power/ground networks.     

基于GCP的基线估计提取高精度DEM研究

合成孔径雷达干涉测量（In＆垛）技术因其独特优势,正逐渐成为高精度数字高程模型（DEM）获取的有力工具,而基线参数估计是利用该技术提取高精度DEM的重要影响因素．本文在现有的基线精确估算方法的基础上,利用典型的基于地面控制点（GCP）法编制了基线估算代码,采用C波段ENVISATASAR雷达数据,对比分析了各算法基线改正的结果,利用校正后的基线参数提取了都江堰地区的DEM,并结合该地区的1：10000地形图对生成的DEM进行了精度评定．研究结果表明,采用基线校正后的数据进行干涉测量生成的DEM在一定条件下能达到国家1：50000数字高程模型三级产品的精度要求．     

温度对混凝土箱梁应力和变形影响的测试与分析

为了研究混凝土箱粱在施工期问的温度场和温度随时问的变化规律.对内蒙古磴口黄河大桥进行了现场测试.分析了混凝土箱梁桥结构的温度效应及温度场对其挠度和应力的影响规律.结果表明:在结构荷载不变的情况下.箱梁的温度应力较易测得;温度对箱梁的应力和挠度均有较大影响,在设计中应予以重视.对如何在混凝土箱梁的施工和设计中考虑温度影响提出了建议.     

一种改进的InSAR干涉相位图估计方法

以联合子空间投影的干涉相位估计算法为基础,结合其应用稳健性问题,提出一种改进的In-SAR干涉相位图估计方法.该方法对联合自相关矩阵进行了加权处理.从幅度上抑制了干扰元素,提高了干涉相位图的精确性.仿真自然场景数据处理结果证明了改进算法的有效性和稳健性.     

PREDICTION OF WELDING DEFORMATIONS BY FEM BASED ON INHERENT STRAINS

IntroductionIt is of importance to predict and control theresidual deformations caused by welding pro-cesses to ensure the accuracy of a welded produc-tion.Nowadays there are three ways to deter-mine the welding deformations:( 1 ) empiricalformulas or curves based on the experiments;( 2 ) thermo- elasto- plastic analysis by FEM;( 3)inherent strain method.The empirical formulasare only suited to the cases of simple plates orbeams that undergo a welding cycle close to theexperiment conditions. …     

高液限土路堤病害机理分析及处治措施

高液限土土性较差,用于修筑路堤容易产生失稳、沉陷等破坏。本着安全有效地利用该类资源,节约换填好土所带来的经济损耗的目的,对高液限土路堤病害机理进行分析,提出利用高液限土修筑路堤的处治建议,以保证高液限土路堤的稳定性,并改善其变形特性。     

高地应力层状软岩隧道大变形预测分级研究

为探明高地应力层状软岩隧道的非对称变形破坏规律及其支护结构的非对称受力特性,结合碳质千枚岩力学特性与变形破坏机制的各向异性特性,对层状软岩隧道围岩的非对称变形破坏特征进行了分析. 在93座典型高地应力层状软岩隧道变形数据的基础上,系统性地分析了隧道拱顶沉降、水平收敛、最大变形量与地应力、岩体抗压强度、隧道埋深之间的关系. 研究结果表明:高地应力层状软岩隧道的变形量与最大地应力、岩体抗压强度、埋深的分布较为离散,在一定地应力、岩体强度或埋深条件下,隧道变形量既存在于高值区间,也存在于低值区间;隧道变形量随地应力的增大、岩体强度的降低、埋深的升高逐渐向高值区间靠拢,高地应力层状软岩隧道大变形是高地应力、软弱围岩、层理弱面耦合作用的结果;基于隧道最大变形量与隧道强度应力比的幂指数变化规律,提出了高地应力层状软岩隧道的大变形预测分级指标.      

一种改进的最小不连续相位解缠算法

提出了一种改进的最小不连续相位解缠算法．根据相位质量图将缠绕相位分为高、低质量区域,高质量区域采用质量引导算法进行相位求解,有效保持了高质量区域的相位解缠精度,低质量区域进行最小不连续优化．对真实InSAR干涉图的处理结果表明,文中方法在提高相位解缠精度的同时极大优化了相位解缠速度．     

软弱层特性对斜坡软弱地基路堤变形的影响

为获得不同软弱层特性条件下斜坡软弱地基路堤的变形规律,建立了斜坡软弱地基在路堤自重荷载作用下的非线性有限元数值模型,探讨了软弱层特性各因素对斜坡软弱地基路堤变形的影响;通过正交试验设计,对软弱层特性各因素对变形影响的显著性进行了评价.结果表明:软弱层土体弹性模量、软弱层厚度是产生过大竖向沉降和侧向变形的决定性因素;地面横坡的存在是加剧地基变形的重要因素;当软弱层位于地基顶面时,对地基变形尤其是侧向变形影响显著;应综合考虑软弱层特性各因素的影响,采取地基处理、侧向约束等工程措施限制变形.      

大跨度悬索拱桥非线性分析

针对某铁路大跨度悬索拱桥，考虑结构的非线性和构件的极限承载能力，计入施工过程的变形和应力的叠加效应，用包含梁和索单元的空间组合结构模型，进行了大桥的结构行为分析。 着重研究了结构在施工及运营过程中的非线性变形、内力和稳定性，并探讨了荷载在悬索拱桥的拱间的分配问题。     

路面典型局部变形激励下的振动舒适性评价

为研究沥青路面局部变形对行驶质量的影响,对路面养护管理中常见的错台型、双断面型和曲面型3类局部变形激励下的振动舒适性进行了评价.首先,建立了局部变形的纵断面简化模型,并基于1/4车理论推导出路面局部变形激励下的人体竖向加速度时域表达式;其次,设计频率加权滤波器对竖向加速度进行滤波,得到瞬时频率加权加速度,从而求解出不同...