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This article explores spatial statistical analysis of the dynamic change of industry sulfur dioxide emission in areas, and we use the data from 31 provinces in China during the years of 1997-2008. We find that the spatial distribution of environmental pollution in provinces shows two distinct characteristics: one is spatial clustering; the other is spatial unbalanced. The two characteristics are stable in the sample range.

In the design of plastic injection molds, the depressions and protrusions (DP) preventing the removal of molded part from mold are referred to as undercuts. This paper describes an approach to recognize DP feature within the curvature region representation based on the curvature properties of entities in B-rep model. The recognized depression features and the concave transitions between protrusion features are potential undercuts which affect the choice of parting directions of the molded part. The possible withdrawal directions of the potential undercuts are derived by geometric reasoning and visibility map computation. This method can recognize isolated and intersecting features with planar, quadric, and freeform surfaces. The identified potential undercuts with their possible withdrawal directions can provide decision support information for mold design such as selecting parting direction, parting lines and surfaces, etc. The case study is presented to verify the feasibility of the developed method.

A full distribution CNC system based on SERCOS bus is studied in accordance with the limitations of traditional PC-based motion card. The conventional PC-based motion control card is dispersed into several autonomous intelligent servo-control units with the function of servo driver. The autonomous intelligent servo-control units realize the loop control of position, velocity and current. Interpolation computation is completed in PC and the computational results are transferred to every autonomous intelligent servo-control unit by high speed SERCOS bus. Software or hardware synchronization technology is used to ensure all servomotors are successive and synchronously running. The communication and synchronization technology of SERCOS are also researched and the autonomous intelligent servo-control card is developed byself. Finally, the experiment of circle contour process on a prototype system proves the feasibility.

The novel information criterion (NIC) algorithm can find the principal subspace quickly, but it is not an actual principal component analysis (PCA) algorithm and hence it cannot find the orthonormal eigen-space which corresponds to the principal component of input vector. This defect limits its application in practice. By weighting the neural network's output of NIC, a modified novel information criterion (MNIC) algorithm is presented. MNIC extractes the principal components and corresponding eigenvectors in a parallel online learning program, and overcomes the NIC's defect. It is proved to have a single global optimum and nonquadratic convergence rate, which is superior to the conventional PCA online algorithms such as Oja and LMSER. The relationship among Oja, LMSER and MNIC is exhibited. Simulations show that MNIC could converge to the optimum fast. The validity of MNIC is proved.

Enterprise application integration (EAI) focuses on the collaboration and interconnection of various information systems, so the basic problem to be solved is how EAI guarantees that the applications will produce consistent presentation of data, message and transaction. The metadata methodology may give us certain good ideas. First, the metadata description method of manufacturing information resource, transaction process and message delivery is put forward on the basis of operation analysis of manufacturing-oriented EAI, and then the tree-structured XML schema of corresponding object is built and a framework of metadata application in the discrete Manufacturing-Oriented EAI is established. Finally, a practical enterprise information integration system in Shanghai Tobacco Machine Co., Ltd. is presented as an example to show how it functions.

A new approach for simulating three-dimensional (3D) bulk metal forming processes is proposed by combining element-free Galerkin method (EFGM) with the flow theory of 3D rigid-plastic/viscoplastic mechanics. Different from the conventional rigid-plastic FEM, the velocity field is constructed by the moving least-squares (MLS) approximation. Special emphasis is placed on the treatments of essential boundary conditions, incompressibility constraint and friction boundaries. The stiffness equation for the analysis of 3D bulk metal forming using EFGM is derived and its key algorithms are given. To test the validity of the proposed meshless approach, a typical 3D upsetting forming process is analyzed and the numerical results are compared with those obtained by commercialized rigid-plastic FEM software Deform3D. As results show, when handling 3D plastic deformations, the proposed approach eliminates the need of expensive meshing and remeshing procedures unavoidable in conventional FEM, and still provides results that are in good agreement with finite element predictions.

When events such as rush orders or machine breakdown occurs during the production process in a job shop, the delivery date of order may be delayed. To solve this problem, an events-oriented job shop scheduling process is built, and a scheduling model integrated with an enterprise information system (EIS), including Enterprise Resource Planning (ERP), Product Data Management/Computer Aided Process Planning (PDM/CAPP), etc., is proposed and analyzed in detail. A genetic algorithm and a hybrid allocation-based method are used in scheduling. Lastly, an events-oriented job shop scheduling simulation system is presented .

The interpolator is the key part of a CNC system, which has strong effect on machining accuracy, tool motion smoothness, and machining efficiency. In this paper, a real-time adaptive interpolator is developed for non-uniform rational B-spline curves (NURBS) interpolation while considering the maximum acceleration/deceleration of the machine tool. In this proposed interpolator, both constant feedrate and high accuracy are achieved while the inconsistency of feedrate is dramatically reduced as well. In order to deal with the acceleration/deceleration around the feedrate-sensitive sharp corners, a look-ahead function is introduced to detect and adjust the feedrate adaptively. Furthermore, a parameter compensation scheme is proposed to eliminate the parametric truncation error which has been analyzed by several researchers but still not incorporated into any real-time interpolator so far. A case study was conducted to evaluate the feasibility of the developed interpolator.

According to the characteristic of high speed drawing frame auto-leveling: open loop can avoid the dead zone, but can’t ease or eliminate the influence of disturbance; close loop can reduce the influence of disturbance, but can’t avoid the dead zone, under the influence of disturbance model is hard to build; and high speed of drawing frame has high demand on hardware and software. Based on new hardware architecture a new auto-leveling control system with mixed loop and fuzzy method is put forward, in which open loop is designed to get the basic control value and close loop inferring from fuzzy control rules to get the increment value and decrease the influence of disturbance by correcting the basic control value obtained from open loop. In conclusion, experiment in FA398 proves the applicability of this system for auto-leveling of high speed drawing frame.

Staggered teeth type rotary burr is a new cutter with a special rotary surface. Since branch cutting edges are interlaced with main cutting edges on the sphere of the rotary burr and only main cutting edges pass by the zenith of the ball, it greatly widens the chip flutes and improves machining properties of cutter teeth nearby the zenith. The machining properties of staggered teeth type rotary burr are better than general ball-end rotary burr’s. Although it is widely used, the research of rotary burr with staggered teeth is not great. In this paper, firstly the helical cutting edge equations on sphere are built. Then, based on the geometry model of helical cutting edge, a helical stagger teeth design is presented and theory of grinding helical grooves of staggered teeth is studied in detail. The smooth spiral rake surface and flank surface can be formed during one-pass grinding process by this method. At last, the validity of the theory given in the paper is identified by example of grinding.

In recent years, the miniaturization of products has become a trend all over the world. Besides conventional precision manufacturing technology and micro-electro-mechanical systems (MEMS), micro/meso mechanical manufacturing (M4) technology is regarded as another choice for an effective method to fabricate micro complicated 3D features, which need special attention paid to. In micro-end-milling machining, the stiffness of a micro-end-milling machine tool is somewhat lower, due to the size effect of material, and also, obviously, the ploughing condition and the quite slender end-milling tool. Thus, the stability of a micro-end-milling machine is very weak. This paper reviews the state-of-the-art of studying chip formation and dynamic problems in micro-end-milling, and discusses the possible future works in this field.

In this paper, an adaptive parametric curve interpolator with a real-time look-ahead function is developed for non-uniform rational B-spline curves (NURBS) interpolation, which considers the maximum acceleration/deceleration of the machine tool. In the proposed interpolator, both constant feedrate and high accuracy are achieved while the inconsistency of feedrate is reduced dramatically as well. In order to deal with the acceleration/deceleration around the feedrate sensitive corners, a look-ahead function is introduced to detect and adjust the feedrate adaptively. Two cases were respectively studied to evaluate the feasibility of the developed interpolator: one is for feedrate sensitive arc corner; the other is for feedrate sensitive sharp corner.

A systematic machining theory and precision method to determine cutter location in a grinding system is presented for rotary burr. First, the helical cutting edge on various kinds of revolving surfaces is built. Then, based on the geometry model of the helical cutting edge, the smooth spiral rake surface with constant normal rake angle and flank surface can been formed during the one-pass grinding process by this method. No interference between the grinding wheel and workpiece happens by the wheel special rotation. The method has the characteristic of detaching the grinding wheel path solution from specified machining conditions. The grinding wheel path is suitable for different NC machine tools through post processing. Meanwhile, a mechanism kinematic model of the NC machine tool is built, and a generalized algorithm for post-processing of multi-axis NC machine tools is presented. This model is applied to arbitrary configuration of NC machine tool, and the motion value for each axis will be generated by the inputting structure and motion parameters of the machine tool. The model, together with the machining method mentioned in this paper, make the calculation and generation of the grinding wheel path simpler and universal. At last, the validity of the method given in the paper is identified by an example of grinding.

A method to find the principal point of an image plane is proposed in this paper for the case of a pincushion distortion. The analytical foundation of the method is that a pincushion distortion causes a pair of distortion-free parallel lines to become a pair of curves, which are termed conjugate curves in this paper, and the shortest line segment connecting the pair of conjugate curves passes through the principal point. Thus, the principal point can be obtained by computing the intersection point of the shortest line segments of different pairs of conjugate curves. However, the case for a digital image is a bit different from the above. For the same pair of conjugate curves, there is a group of shortest line segments, which is called a shortest segment set. The coincidence region of the shortest segment sets of different pairs of conjugate curves is a polygon, the centroid of which is considered as the principal point. Therefore, the proposed method firstly needs to capture the pincushion-distorted images of some pairs of parallel lines, secondly to find the corresponding polygon and lastly, to calculate the centroid point. A synthetic image and a real image are tested using this method, and the results are satisfying.

Spur gears were typically analyzed in the past using two-dimensional (2-D) Finite Element (FE) models. This is not adequate in many cases. A three-dimensional (3-D) FE model of a spur gear system, which accommodates all the gear teeth, the gear bodies, and the two transmission shafts, is developed in this paper using a sub-structuring method. The load between pinion and gear wheel is delivered by elastic frictional contact. The contact problem is solved according to the FE parametric quadratic programming method. The paper presents the shape of the contact region as well as the load distribution along the tooth width and profile. The results show that the transmission shafts have significant effects on the contact conditions including load distribution, contact region, and load deviation. The proposed method also applies to other types of gearing.

This paper presents a new method for modelling and operation optimization of large scale water injection systems. Systems of tms Kma usually consist of a great number of water injection stations.pipelines.valves.pipe fittings,and water injection wells, and is a multi-source multi-sink nonlinear time-vaiying system with thousands of vanables. A properly simplified and sufficiently accurate mathematical model lias been made by both the analytical method and the system identification method. A new operation optimization method has been developed for this system by the large scale system theory and the dynamic programming method To solve this optimization problem.the concept of pressure valley in hydrodynamic system is presented for the first time in this paper. The water uniection system is divided into a senes of subsystems according to pressure valleys It has been proved 1 that system optimization on the whole is equivalent to optimization of every subsystem in it if coupling variables of the subsvstems have the values resulting from the optimized system. Thus, rhe system optimization problem is decomposed into a senes of subsystem optimization problems. The above modelling method and operation optimization procedures are programmed in a software package. This package has been applied to an oilfield in Daqing Electnc power consumption for water injection decreased by 3- 10%,and waterflood efficiency improved.

In order to solve one Gordian knot of how to optimize the control curve of variable blank holder force (VBHF) in the process of sheet deep drawing, some plasticity analyses in theory about carry capacities of one point on the surface of flange and one point on the sidewall during the whole process of deep drawing cylinder parts were carried out firstly, and then instantaneous radial pull-stress and circumferential compress-stress formulas about one random point on the flange could be concluded out by the way of building corresponding stress-strain balance relations, the same as the corresponding max pull-stress formula about one point on the sidewall. By the aid of consulting with correlative energy conversation theorem, Hill anisotropism theory and materials strain-hardening criterion, one minimum wrinkleless VBHF expression which including friction coefficient and normal anisotropism coefficient and one critical fracture limit VBHF expression could be ratiocinated out in sequence, and some corresponding influencing disciplines of all kinds of forming parameters on these two expressions were discussed in detail. In the end, numerical simulations were adopted to validate the feasibility of two simple optimized load curves of VBHF. Final computation results showed that these two simple optimized VBHF curves could not only conduce to more uniform in thickness distribution relative to other’s study results, after calculating mean square deviation of thickness variation with final parts, but also attain to lower peak with thickness variation, which dropping from 7.47% to 6.17% and from 17.65% to 15.39% respectively.

The difficulties of machine sounds failure diagnosis lie in the detected interested signal being polluted by many other noises which led to low signal noise ratio. In order to extract interested machine sounds, an efficient blind separation algorithm was presented. It first extracts the p largest eigenvalues of covariance matrix of observed signals by simple parallel adaptive principal component anslysis preprocessing algorithm, and then estimates the p source by Natural Gradient algorithm. The output signals are always the p largest energy components of X. Its preprocessing and separation steps all exploit adaptive approach. The algorithm can deal with super-Gaussian, Gaussian and sub-Gaussian signal, has low computation complexity and is suitable for real-time application. Simulations show that it is feasible and effective for blind source separation of distorted machine sounds.

In today's challenging global market, companies are embracing PLM (product lifecycle management) as an important information strategy to achieve their business goals of T (time), Q (quality), C (cost), S (service), and E (environment). Based on the discussion on the connotation of PLM, the author deems that for product users, the core of PLM is provide powerful data support for fast and precise data query or capturing. Through analyzing on the product structure and production process of manufacturing enterprises, this paper points out that the traditional BOM data model, owing to its own limitation, can no longer meet the need of PLM. The only way for enterprises to walk out the dilemma of manufacturing information is finding out a proper product structure and production data model. To the problems encountered in the course of implementing PLM, a multidimensional data model is presented in this paper. Its definition and expression is detailed, its realization technology is studied, and its data structures are designed with UML (Unified Modelling Language) class diagram. The presented model is unified, holonomic and dynamically extensible, thus addresses the need of PLM very well.

At present there are few well-considered systematic theories and determinate methods for designing hydraulics. Engineers in various fields mainly rely on their own practical experience and use the manual method of design. The quality of designed projects largely depends on the ability of designers. However, experts are limited in number, so it is necessary to research the design theory and practice of hydraulics, sum up the experience of experts and use the computer to simulate experts’ design procedures.