条件颗粒分割方法研究

图像中两个物体的接触关系根据粒径可分为未接触、不同粒度物体的接触和同粒度物体的接触3种，接触物体根据接触部分的大小又可分为强接触、中等接触和弱接触。对接触物体的保形分割应该是使分割后物体恢复原来的形态，鉴于流域分割、测地重建等算法在分割接触物体时，不但对物体形态产生破坏和受干扰因素多，而且对于计算接触面积大小的问题，以上算法也不易实现，为此，提出了条件颗粒分割方法，即在数学形态学开运算过程中，对标定区域腐蚀后，不再做膨胀运算，就直接在保形的基础上，对不同粒度的物体进行分割，而对于同粒度接触的物体，则先通过腐蚀后，再做一次特殊条件颗粒分割来得到小粒度(条带)部分，再进行复原就是目标物体的接触部位。最后，介绍了此算法在岩石颗粒粒度分析及胶结类型划分方面的应用。     

二维图形的二叉树表示

用二叉树表示二维图形的一个重要优点是层次分明.分层对图形的识别和分析是很有用的,但是这要求每一分层对原图能保真.本文取弧的惯量为特性值,用线生长法[1]来构造二叉树的方法,取得图形分层表示的好结果.     

Applications of approximate string matching to 2D shape recognition

A new method for the recognition of arbitrary two-dimensional (2D) shapes is described. It is based on string edit distance computation. The recognition method is invariant under translation, rotation, scaling and partial occlusion. A set of experiments are described demonstrating the robustness and reliability of the proposed approach.     

Morphological analysis of discrete random shapes

In this paper I discuss a number of theoretical issues regarding the morphological analysis of discrete random shapes by means of Matheron's random set theory. I revisit this theory by limiting myself to the discrete case, since most image data are available in a discrete form. Although it may seem that the transition from the continuous to the discrete case is straightforward (since most of Matheron's theory is general enough to incorporate the discrete case as a special case), this transition is often challenging and full of exciting and, surprisingly, pleasant results. I introduce the concept of the cumulative-distribution functional of a discrete random set and review some fundamental properties of the capacity functional (a fundamental statistical quantity that uniquely defines a random set and relates random set theory to mathematical morphology). In analogy to a recent result and under a natural boundness condition, I show that there exists a one-to-one correspondence between the probability-mass function of a discrete binary random field and the corresponding cumulative-distribution functional. The relationship between the cumulative-distribution functional and the capacity functional of a discrete random set is also established. The cumulative-distribution and capacity functionals are related to the higher-order moments of a discrete binary random field, and, therefore, their computation is equivalent to computing these moments. A brief discussion of how to perform such computations for a certain class of discrete random sets is provided. The capacity functional of a morphologically transformed, continuous random set cannot be associated to the capacity functional of the random set itself, except in the case of dilation. I show that the derivation of such an association is possible in the discrete case and for the cases of dilation and erosion and more complicated morphological transformations, such as opening and closing. These relationships are then used to derive a fundamental result regarding the statistical behavior of opening and closing morphological filters. I also show that the probability-mass function of a discrete binary random field may be expressed in terms of the cumulative-distribution functional or the capacity functional of a morphologically transformed discrete random set by means of a hit-or-miss transformation. I also introduce moments for discrete random sets, which permit generalization of the concepts of autocorrelation and contact distribution. Furthermore, I demonstrate the fact that the class of opening-based size distributions, introduced axiomatically by Matheron, are higher-order moments of a discrete random set, therefore statistically demonstrating that size distributions are good statistical summaries for shape. Finally, convex random sets are viewed in the discrete domain. My final result regarding convexity, is similar to Matheron's. However, the tools used here for the derivation of such a result are different from the ones used by Matheron, whose approach to this subject is limited to the continuous case.     

Robust stabilisation of 2D state-delayed stochastic systems with randomly occurring uncertainties and nonlinearities

This paper is concerned with the state feedback control problem for a class of two-dimensional (2D) discrete-time stochastic systems with time-delays, randomly occurring uncertainties and nonlinearities. Both the sector-like nonlinearities and the norm-bounded uncertainties enter into the system in random ways, and such randomly occurring uncertainties and nonlinearities obey certain mutually uncorrelated Bernoulli random binary distribution laws. Sufficient computationally tractable linear matrix inequality–based conditions are established for the 2D nonlinear stochastic time-delay systems to be asymptotically stable in the mean-square sense, and then the explicit expression of the desired controller gains is derived. An illustrative example is provided to show the usefulness and effectiveness of the proposed method.     

Automatic layout of 2D free-form shapes based on geometric similarity feature searching and fuzzy matching

Two-dimensional (2D) irregular layout is widely applied in various manufacturing processes, such as sheet metal cutting, shipbuilding, and electronic component placement. An efficient layout algorithm can effectively improve the material utilization, thereby reducing manufacturing cost. But the free-form shape layout problem is very challenge as it is difficult to exactly represent a free-form shape. There is not an efficient method currently available for the 2D free-form shape layout. This paper proposes a method based on the geometric similarity feature searching and fuzzy matching for the 2D free-form shape layout. The freeman chain code is developed to describe the contour information of shapes and forward-lines to form the basis of the layout strategy. A strategy based on fuzzy matching is proposed for the layout, which includes searching geometric similarity features using the longest common subsequence and the proposed placement algorithm to complete the collision. Three computational experiments are conducted to analyze the performance of the proposed method. Experimental results show that the proposed method is feasible and effective with the good applicability to achieve a high filling rate in reduced time.     

Acquisition of 2D Shape Models from Scenes with Overlapping Objects using String Matching

In this paper we describe a system that is able to acquire models of 2D shapes from cluttered scenes. The input of the system is a sequence of images, each of which shows an unknown number of overlapping unknown 2D objects. The system identifies matching partial shapes across different images and combines them into complete 2D shape models, thus giving a complete interpretation of the input scenes. The identification of partial shapes is based on string matching, whereas a graph search procedure is used for shape model generation. The system has been fully implemented and tested on images containing parts of a jigsaw puzzle. Received: 20 November 1998?Received in revised form: 24 December 1998?Accepted: 4 January 1999     

Visual processing and classification of items on a moving conveyor: a selective perception approach

Many industrial applications require some sort of automated visual processing and classification of items placed on a moving conveyor. In this paper, we present a selective perception based approach to visual processing. The novelty of this approach is that instead of processing the whole image, only areas that are deemed ‘‘interesting’’ and hence calling for attention are analyzed. The attentional sequences thus constructed can then be used for a variety of tasks including shape determination. Since only a small portion of the whole image is processed, visual processing can be real-time and flexible without requiring special hardware. Two different applications based on this approach are described. In a defective item detection task, we explain in detail how attentional sequences can be used. As a second application, the approach has been implemented in an automated remote controller sorter in a TV manufacturing plant—thus confirming its practical applicability.     

Robust stabilization of nonlinear stochastic 2‐D systems: LaSalle‐type theorem approach

LaSalle theorem (also known as the LaSalle invariance principle) plays an essential role in the systems and control theory. Recently, it has been extensively studied and developed for various types of one‐dimensional (1‐D) systems including deterministic and stochastic 1‐D systems in discrete‐ and continuous‐time domains. For two‐dimensional (2‐D) systems, such studies have received considerably less attention. In this article, based on discrete martingale theory, a LaSalle‐type theorem is first developed for a class of discrete‐time nonlinear stochastic 2‐D systems described by a Roesser model. The proposed result can be regarded as an extension of stochastic Lyapunov‐like theorem, which guarantees the convergence almost surely of system state trajectories. Extensions to the problem of optimal guaranteed cost control of nonlinear stochastic 2‐D systems are also presented. The proposed schemes are then utilized to derive tractable synthesis conditions of a suboptimal state‐feedback controller for uncertain 2‐D systems with multiplicative stochastic noises. The effectiveness of the obtained results is illustrated by given numerical examples and simulations.     

三维立体视觉机械臂智能抓取分类系统的开发

采用工业相机、工业投影机、普通摄像头、计算机和机械臂开发了一套具有三维立体视觉的机械臂智能抓取分类系统。该系统采用自编软件实现了对工业相机、工业投影机的自动控制和同步，通过前期研究提出的双波长条纹投影三维形貌测量法获取了物体的高度信息，结合opencv技术和普通摄像头获取的物体二维平行面信息，实现了物体的自动识别和分类；利用串口通信协议，将上述处理后的数据传送至机械臂，系统进行几何姿态解算，实现了智能抓取，并能根据抓手上压力反馈自动调节抓手张合程度，实现自适应抓取。经实验证明该系统能通过自带的快速三维形貌获取装置实现准确、快速的抓取工作范围内的任意形状的物体并实现智能分类。     

Robust design of iterative learning control for a batch process described by 2D Roesser system with packet dropouts and time‐varying delays

Batch process, working as a best choice for low‐volume and high‐value products in manufacturing, has been widely used in chemical industries. The actuator faults and time delays often occur in practical production. This paper develops an iterative learning control (ILC) design for a batch process described by two‐dimensional (2D) Roesser system with packet dropouts and time‐varying delays. The phenomenon of actuator faults is regarded as an arbitrary stochastic sequence satisfying the Bernoulli random binary distribution. Firstly, the ILC design for a batch process is transformed into stability analysis for a 2D stochastic system with time‐varying delays. Secondly, for analyzing the stability of 2D stochastic systems, we derive the stability condition in terms of linear matrix inequality. Then, we give a procedure to get the control gain for the ILC design. An injection modeling process as an example with simulations in different cases of data dropout is given to demonstrate the validity of the proposed method. Furthermore, the proposed method has a better result by comparing the existing methods.     

一类不确定的2D 非线性时滞系统的鲁棒能稳

研究一类参数不确定的2D时滞系统满足Lipschitz条件的非线性Fornasini Marchesini 模型（简称2 DFM II）的鲁棒能稳问题,即设计静态状态反馈控制律，使得对所有容许的不确定参数，闭环系统稳定．通过求解线性矩阵不等式（LMI），给出了问题可解的充分条件及静态状态反馈控制律的设计方法．最后通过数值算例验证了方法的有效性．     

Robust design of feedback integrated with iterative learning control for batch processes with uncertainties and interval time-varying delays

A robust feedback integrated with iterative learning control (FILC) scheme for batch processes with uncertain perturbations and interval time-varying delay is developed. The batch process is modeled as a two-dimensional (2D) Rosser system with a delay varying in a range. The design of FILC scheme is transformed into a robust control problem of uncertain 2D system. New delay-range-dependent stability criteria and stabilization conditions are derived in terms of linear matrix inequalities (LMIs), which depend on not only the difference between the upper and lower delay bounds but also the upper delay bound of the interval time-varying delay. Parameterized characterizations for stabilizing the controller are given in terms of the feasibility solutions to the LMIs. Applications to injection velocity control show that the proposed FILC achieve the design objectives well.     

Partial Shape Matching Using Transformation Parameter Similarity

In this paper, we present a method for non‐rigid, partial shape matching in vector graphics. Given a user‐specified query region in a 2D shape, similar regions are found, even if they are non‐linearly distorted. Furthermore, a non‐linear mapping is established between the query regions and these matches, which allows the automatic transfer of editing operations such as texturing. This is achieved by a two‐step approach. First, pointwise correspondences between the query region and the whole shape are established. The transformation parameters of these correspondences are registered in an appropriate transformation space. For transformations between similar regions, these parameters form surfaces in transformation space, which are extracted in the second step of our method. The extracted regions may be related to the query region by a non‐rigid transform, enabling non‐rigid shape matching.     

A workflow for handling heterogeneous 3D models with the TOUGH2 family of codes: Applications to numerical modeling of CO2 geological storage

This paper is addressed to the TOUGH2 user community. It presents a new tool for handling simulations run with the TOUGH2 code with specific application to CO₂ geological storage. This tool is composed of separate FORTRAN subroutines (or modules) that can be run independently, using input and output files in ASCII format for TOUGH2. These modules have been developed specifically for modeling of carbon dioxide geological storage and their use with TOUGH2 and the Equation of State module ECO2N, dedicated to CO₂-water-salt mixture systems, with TOUGHREACT, which is an adaptation of TOUGH2 with ECO2N and geochemical fluid-rock interactions, and with TOUGH2 and the EOS7C module dedicated to CO₂-CH₄ gas mixture is described. The objective is to save time for the pre-processing, execution and visualization of complex geometry for geological system representation. The workflow is rapid and user-friendly and future implementation to other TOUGH2 EOS modules for other contexts (e.g. nuclear waste disposal, geothermal production) is straightforward. Three examples are shown for validation: (i) leakage of CO₂ up through an abandoned well; (ii) 3D reactive transport modeling of CO₂ in a sandy aquifer formation in the Sleipner gas Field, (North Sea, Norway); and (iii) an estimation of enhanced gas recovery technology using CO₂ as the injected and stored gas to produce methane in the K12B Gas Field (North Sea, Denmark).