当期目录

    2006年, 第28卷, 第S3期 刊出日期:2006-11-20
      
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  • . 2006, (S3):  12-16. 
    摘要 ( )   
    In conventional cross-coupled controller design,the method usually ignored the inherent characteristic of time-vary- ing parameters and model uncertainties in system.In this paper,a cross-coupled controller(CCC)using an H~∞control scheme has been proposed to reduce the contouring error for an X-Y table.Furthermore,the proposed CCC design,which is a typical Multi- Input Multi-Output(MIMO)system with linear time varying(LTV)characteristics,has been verified as being internally stable. The simulations are carried on Matlab simulink to verify the proposed method,and the results showed that the proposed method can reduce the contouring error significantly compared with the conventional one.
  • . 2006, (S3):  17-20. 
    摘要 ( )   
    An effective and reliable access control is crucial to a PDM system.This article has discussed the commonly used access control models,analyzed their advantages and disadvantages,and proposed a new Role and Object based access control model that suits the particular needs of a PDM system.The new model has been implemented in a commercial PDM system,which has demonstrated enhanced flexibility and convenience.
  • . 2006, (S3):  21-24. 
    摘要 ( )   
    In CNC heavy cutting servo system,mechanical driving system has a torture feedback on electrical speed-adjust- ment system,thus it's possible to generate the mechanical resonance.The mechanical resonance makes the feature parameters of me- chanical driving system influence the dynamic performance of the electrical speed-adjustment system.This paper has studied the re- sistance ratio ofζ_(mech)and q parameters,and put forward the compensation method to decrease the mechanical resonance influence.
  • . 2006, (S3):  25-28. 
    摘要 ( )   
    Triangular mesh is often used to describe geometric object as computed model in digital manufacture,thus the mesh model with both uniform triangular shape and excellent geometric shape is expected.But in fact,the optimization of triangu- lar shape often is contrary with that of geometric shape.In this paper,one synthesized optimizing algorithm is presented through subdividing triangles to achieve the trade-off solution between the geometric and triangular shape optimization of mesh model.The result mesh with uniform triangular shape and excellent topology are obtained.
  • . 2006, (S3):  29-33. 
    摘要 ( )   
    Wall thickness is always a key index for boiler tube inspection in power plant,in order to improve the inspection efficiency and accuracy,a new method fusing the magnetic and ultrasonic technique was proposed.The magnetic technique was used to do full inspection and locate the flaws,and the ultrasonic was employed to implement further quantitative inspection accu- rately.After comparing the precision of the polynomial,exponential and logarithmic function,the polynomial model was selected to fit the relations between the wall thickness and the peak value of magnetic signals,and the data measured by ultrasonic thickness meter was used to calibrate the model parameters online,the defect depth can be sized quickly.The experimental results demon- grate that the model used in this system has better accuracy than the statistics relation model clearly,and it is also suitable for defect evaluation real-time.Moreover,it is unnecessary to have much more experimental data for the curve fitting technology,so it has better practicability than the other methods.
  • . 2006, (S3):  34-38. 
    摘要 ( )   
    More and more small and medium enterprises(SMEs)carry professional information systems into effect by Appli- cation Service Provider(ASP).However,lots of ASP has just single function so that they can't meet needs for collaborative com- merce among SMEs.Therefore,the ASP-based Services Alliance(ASA)is proposed to raise level of information application for SMEs.The formation process of ASA is introduced,some key methods supporting ASA formation are presented and the practice of ASA in Guizhou province which was developed with the key methods discussed.SMEs can get high quality,low cost online services and the ability of capturing market with allied member collaboratively through ASA.
  • . 2006, (S3):  39-43. 
    摘要 ( )   
    In modern manufacturing equipment control area,controller is required to deliver higher computing capability for adopting advanced algorithms to meet speed and accuracy requirements,and reconfigurabilities for changing or(and)adding features or functions.This paper presents a methodology in design and implementation of a high performance and reconfigurable platform for manufacturing equipment control.This methodology is in virtue of system on a programmable chip(SoPC)technolo- gy but replacing the on-chip processor by an external high performance,floating-point digital signal processor(DSP).The appli- cation of the DSP is designed as a multi-threaded framework,which has more flexibilities than a traditional single-loop one.Fur- thermore,the field programmable gate array(FPGA)system can be reconfigured easily and quickly to meet a new requirement by dragging and dropping pre-built components in a SoPC building environment.As a result,the controller platform is more recon- figurable in terms of algorithms and functions.This platform is implemented in a 3-axis milling machine control and the result indicates that the design and implementation presented in this paper is feasible.
  • . 2006, (S3):  44-48. 
    摘要 ( )   
    Metal forming plays an important role in manufacturing industry and is widely applied in industries.The tradi- tional finite element method(FEM)numerical simulation is commonly used to predict metal forming process.Conventional finite element analysis of metal forming processes often breaks down due to severe mesh distortion,therefore time-consuming remeshing is necessary.Meshfree methods have been developed since 1977 and can avoid this problem.This new generation of computational methods reduces time-consuming model generation and refinement effort,and its shape function has higher order connectivity than FEM's.In this paper the velocity shape functions are developed from a reproducing kernel approximation that satisfies consistency conditions and is used to analyze metal tension rigid viscoplastic deforming and Magnesium Alloy(MB 15)sheet superplastic ten- sion forming.A meshfree method metal forming modeling program is set up,the partition of unity method is used to compute the integrations in weak form equations and penalty method is used to impose the essential boundary condition exactly.Metal forming examples,such as sheet metal superplastic tension forming and metal rigid viscoplastic tension forming,are analyzed to demon- strate the performance of mesh free method.
  • . 2006, (S3):  49-52. 
    摘要 ( )   
    The production model of“multi-specification and low-quantity”is becoming the main trend of manufacturing industry.As a key activity in the manufacturing chain,traditional computer aided process planning(CAPP)system fails to adapt to the production model of customization.Therefore,a novel method for variant design of process planning was proposed to develop CAPP system based on Tabular Layouts of Article Characteristics(Sach-Merk Leisten in German and SML for short). With the support of standard database of master process planning documents which are developed by parameterization technique, and instance process planning for special product(instance product)can be generated automatically by the sub-system of variant de- sign of process planning.Finally,a CAPP system was developed for process design of rotor of steam turbine to validate the feasibil- ity and applicability of the method.
  • . 2006, (S3):  53-56. 
    摘要 ( )   
    Thin-walled structures have been widely used in the aerospace industry.The dynamic interaction between the milling cutter and thin-walled workpiece can easily lead to vibration.This paper investigates the vibration caused during milling the thin-walled workpiece on the NC machining center,presents a theoretical milling vibration model of thin-walled beam.The model was verified by using milling experiments and numerical simulations.Some valuable conclusions are derived,this will be references to scientific research and guides to the vibration-free milling of thin-walled structures at different cutting speeds.
  • . 2006, (S3):  57-61. 
    摘要 ( )   
    The remote data collection system based on SOL Server database technology was developed by Visual C++and SQL Server database technology together.The Client/Server mode was adopted.The system adopted the database search technologi- cal-ADO to work out the communication procedure of the server.And the old data of corresponding memory units were upgraded by the new data which gathered from PLC through serial port real time in the database.The Client utilizes the network technology and database technology through queries procedure to access the data information in the database.Thus a large number of relevant data that the production line operated were obtained.The goal of understanding operation conditions of product line was achieved through analysis of these data.This system has been debugged by the experiment successfully.
  • . 2006, (S3):  62-65. 
    摘要 ( )   
    This paper will introduce two types of multi-parameter co-measuring system and their application in the produc- tion.The first is crankshaft bent deformation measuring machine system.The second is the crankshaft pneumatic-electric measur- ing system.They have been used in final inspection procedure of automation line for crankshaft of automobie engine with good re- sults,the structure principle and soft clash technological process of the measurement system are presented.
  • . 2006, (S3):  66-69. 
    摘要 ( )   
    Laser shot peening forming is a novel technology,which employs residual stress induced by intense laser to shape precisely the plate.In this paper,the aeronautic aluminum alloy LY12CZ was selected as an object to research experimentally the magnitude of deformation versus numbers of laser shot peening,and surface quality in laser shot zone was also investigated.The specimen was impacted along its centerline by the high-power,short-duration pulses laser.The experimental results show that the arc height and hardness becomes greater with numbers of shot peening increasing and eventually arrives to saturated state,and sur- face roughness after laser shot peening decreases slightly and dislocation density increases greatly,which indicates that the laser shot peening is a technique combining laser shock processing and metal forming.
  • . 2006, (S3):  70-75. 
    摘要 ( )   
    Under the circumstance of buyer's market,the general core competence of supply chain is radically determined by the core competence of distributors facing customers directly.Based on the analysis of channel management and creation model,the traditional Manufacture-Distributor relationship is discussed including the disadvantages of common distributor Core Competence e- valuation.Meanwhile,In this paper,the Logarithm Triangular Fuzzy Number-AHP method is creatively used to evaluate the strategic distributor Core Competence evaluation index system.This method also overcomes some disadvantages that experts can di- rectly give definite numbers when the traditional AHP method is used to value certainty and measure the qualitative index.More important,it is a scientific qualitative and quantitative evaluation tool.Then the real cases are researched based on all discussions above.
  • . 2006, (S3):  76-78. 
    摘要 ( )   
    In laser beam scanning manufacturing(LSM)system the PLT file was adopted as design file.The data of de- sign file were processed by CAD software programmed.And the control model was adopted DEA control model.The DEA model was concerned with not only the distance of the two swaying mirrors,the distance between the swaying mirror and convex lens,the mirror swaying angle and the lens focal length but also the lens central height,the lens convex radius and the medium refractive in- dex.It improved the precision and reduced the error in LBM system.The application of CAD/CAM system in LSM improved the LSM manufacturing velocity and manufacturing quality.
  • . 2006, (S3):  79-86. 
    摘要 ( )   
    The modern industrial control objects become more and more complicated,and higher control quality is required, so a series of new control strategies appear,applied,modified and develop quickly.This paper researches a new control strategy- prediction control-and its application in Multi-Variable Control Process.The research result is worthy for automatic control in pro- cess industry.
  • . 2006, (S3):  87-89. 
    摘要 ( )   
    A balancing technique for casting or forging parts to be machined is presented in this paper.It allows an optimal part setup to make sure that no shortage of material(undercut)will occur during machining.Particularly in the heavy part in- dustry,where the resulting casting size and shape may deviate from expectations,the balancing process discovers whether or not the design model is totally enclosed in the actual part to be machined.The alignment is an iterative process involving nonlinear con- strained optimization,which forces data points to lie outside the nominal model under a specific order of priority.Newton methods for non-linear numerical minimization are rarely applied to this problem because of the high cost of computing.In this paper, Newton methods are applied to the balancing of blank part.The aforesaid algorithm is demonstrated in term of a marine propeller blade,and result shows that The Newton methods are more efficient and accurate than those implemented in past research and have distinct advantages compared to the registration methods widely used today.
  • . 2006, (S3):  90-95. 
    摘要 ( )   
    A control strategy for real-time target tracking for wheeled mobile robots is presented.Using a modified Kalman filter for environment perception,a novel tracking control law derived from Lyapunov stability theory is introduced.Tuning of linear velocity and angular velocity with mechanical constraints is applied.The proposed control system can simultaneously solve the target trajectory prediction,real-time tracking,and posture regulation problems of a wheeled mobile robot.Experimental results illustrate the effectiveness of the proposed tracking control laws.
  • . 2006, (S3):  96-100. 
    摘要 ( )   
    Approximate calculation methods of prevention maintenance period under the random distribution are given,and three kinds of approximate calculation models of prevention maintenance period based on different security demands are come up with according to maintenance problems of machinery systems in modern enterprise and starting with different demands of systems. And then,how to make certain the best maintenance period by using the approximate calculation methods is illustrated by an exam- ple.
  • . 2006, (S3):  101-104. 
    摘要 ( )   
    Based on similarity science and complex system theory,a new concept of characteristic self-diversity and corre- sponding relations between self-similarity and self-diversity for complex mechanical systems are presented in this paper.Methods of system self-similarity and self-diversity measure between main system and sub-system are studied.Numerical calculations show that the characteristic self-similarity and self-diversity measure method is validity.A new theory and method of self-similarity and self- diversity measure for complexity mechanical system is presented.
  • . 2006, (S3):  105-110. 
    摘要 ( )   
    An effective evolutionary method for solving the structural topology design problems of heat conductive fields is presented in this paper.The topology optimization model based on minimizing the heat transport potential capacity dissipation of heat conductive field is then established and the corresponding sensitivity of objective function is derived to determine which elements would be removed of the heat conductive field for having the increment of the objective heat transport potential capacity dissipation minimized.A Filtering technique is employed in sensitivity field to eliminate numerical instabilities in the evolutionary procedure. Numerical examples are presented to demonstrate the validity and the engineering applicability of the evolutionary method by con- trast with SIMP method,meanwhile we can come to a conclusion that higher speed of convergence and clearer optimal topology dis- tribution without intermediate elements can be attained by using evolutionary strategy,with the results laying a reliable foundation for the subsequent shape and size optimizations in thermal engineering.
  • . 2006, (S3):  111-115. 
    摘要 ( )   
    Along with the popularity of enterprise applications,the management reform of manufacturing enterprise(ME) relies on the business process reengineering is gradually invalid.Reviewing and comparison the former structure of different enter- prise such as extend enterprise,virtual enterprise etc.from the perspective of link,unit,and focus.Through comparison the evo- lution of ME structure the configurable enterprise(CE)was put forward which based on the information and communication tech- nology providing a new mechanism for the elements configuration and the resources allocation.Based on the reference model of en- terprise business architecture,the framework of CE was raised,which includes enterprise business architecture,business model and component.Then modeling the dynamics of CE,the mechanism of key success factors interactions was analyzed and verified the key factors that de decided the evolution of CE which could forecast the development trend of manufacturing enterprise.
  • . 2006, (S3):  116-120. 
    摘要 ( )   
    Toroidal composite vessel winded with fiber is a new kind of structural pressure vessels,which not only has high structure efficiency of compound materials pressure vessel,good security and so on,but also has special shape and the property of u- tilizing toroidal space,and the prospect of the application of toroidal composite vessel winded with fiber is extremely broad.By in- troducing parameters establishment of toroidal vessel and elaborating the principle of filament winding for toroidal vessel,the de- sign model of filament winding machine for toroidal vessel has been introduced,and the design model has been dynamically simu- lated by the software of ADAMS,which will give more referrence for the design of real toroidal vessel twister.
  • . 2006, (S3):  121-127. 
    摘要 ( )   
    Advanced manufacturing technology(AMT)is pivotal for firms to gain manufacturing performance and com- petitive advantage.Job characteristics,as a kind of important factors affecting the implementation effects of AMT ,have become the focus in the field of academy.Based on a literature review,this study refines the implementation effects of AMT into opera- tional performance,satisfaction and competitive performance,and reclassifies the job characteristics of AMT into job autonomy, job responsibility,job complexity and job significance.With a large sample of 307 equipment-manufacturing firms selected from the 2005 China International Equipment and Manufacturing Exposition,linear structural equation analysis(LIEREL)is per- formed to examine the relationships between job characteristics and the implementation effects of AMT.The results show that job re- sponsibility and job significance have positive effects on satisfaction;satisfaction is positively correlated with operational perfor- mance;operational performance positively affects competitive performance.The findings provide the guide for firms to improve satisfaction,achieve higher operational performance and further gain higher competitive by reasonable job redesign.
  • . 2006, (S3):  128-131. 
    摘要 ( )   
    The FW process is a prefect method of manufacturing FRP composite air vessel resisting high pressure and aerial press vessel.In this paper FW pattern of FRP composite air vessel resisting high pressure was analyzed in a nutshell.The stability of FW patterns on end head is very sensitive to changing of pattern parameter.Consequently,its FW pattern was based on geodesic track.The FW angles and on equators depend on the dimension of end part and the condition of geodesic FW.Generally speaking, the polar holes of rocket engine shell are disproportional.Therefore,the FW angles of the shell column are changeable.The feasi- bility of nongeodesic FW of the shell column was discussed in this paper.Furthermore,it expounded the indispensable condition be- tween the length of shell column and the FW friction coefficient.At the same time,the general mathematic models of the movement control of nongeodesic FW were deduced.
  • . 2006, (S3):  132-136. 
    摘要 ( )   
    This paper took Pro/ENGINEER wildfire2.0 as the development environment and realized the involute helical gears'three-dimensional model parameterized designing which made use of the parameter and relation function of Pro/E.This paper also provided a method of editing the equation of the tooth curve,and it can ensure the high precision of the involute helical gear model.It developed the man-machine interactive parameterized designing interface making use of the secondary development function offered by Pro/TOOLKIT.The users can revise the involute helical gear easily by this man-machine interactive.It de- tailedly introduced the method of designing the man-machine interactive interface Using Pro/TOOLKIT and Visual C++.When the users input correlation parameters according to the prompt of the man-machine interactive interface,the three-dimensional model of the involute helical gear is auto-generated.This method simplified the product design process,shortened the period of de- veloping and improved the design efficiency of the gear greatly.
  • . 2006, (S3):  137-141. 
    摘要 ( )   
    In the design of crane,designers often have to study the trajectory of amplitude-adjusting of crane.The tradition- al methods,illustration and analytics both show their limits.In this paper,the simulation of process of amplitude-adjusting is presented and the optimization is also performed with virtual prototyping technology.From the comparison of original solution and optimal solution,the effectiveness of this technique is testified.On the platform ADAMS/View,the interactive optimization can be performed in a visual,intuitive and credible way,which deserves to be introduced to the design of crane.
  • . 2006, (S3):  142-146. 
    摘要 ( )   
    Digital factory technology is a research focus in academe and industry,which is an advanced manufacturing tech- nology that is proposed to bridge product development and manufacturing.For applying digital factory technology in machining domain,a concept of digital process planning and its framework are suggested,its components including machining domain knowledge model,machining knowledge base,machining resource base and process planning system are studied.The framework of digital process planning is of value for implementing digital factory technology in machining industry.
  • . 2006, (S3):  147-152. 
    摘要 ( )   
    VRML(Virtual Reality Modeling Language)format as an international standard for virtual reality,has al- ready been widely adopted for graphical representation of 3D objects over the Web.Adopting VRML model in RP(Rapid Prototyp- ing)can reduce the precision loss which is caused by triangulation in generating STL file.Hence exploring a slicing method and de- veloping a slicing software for VRML model is important and significant to improve the accuracy of RP products.Finding inter- sections of a plane and VRML model is the key operation in slicing algorithm.This paper presents a method for calculating the in- tersections between a set of parallel planes and VRML geometric primitives.Based on the analysis of the relative position between a plane and a geometric primitive,intersection conditions in all cases were obtained,and the geometric parameters and corresponding equations of intersections were derived.The algorithm had been tested,and applications show that it is robust and effective.
  • . 2006, (S3):  153-157. 
    摘要 ( )   
    Geographic information system(GIS)technology is a combination of computer's graphic and database to store and process spatial information.According to the users' demands,GIS exports the exact geographic information and related in- formation for users with map and description through associating geographic place and related attributes.Based on the existing pop- ular technology,this paper presents a distributed web GIS application based on component technology and fractal image compres- sion.It presents the basic framework of the proposed system at first,and then discusses the key technology of implementing this sys- tem;finally it designs a three-layer WEB GIS instance using VC++ATL based on Geo Beans.The example suggests the proposed design is correct,feasible and valid.
  • . 2006, (S3):  158-164. 
    摘要 ( )   
    The NC programming for complex components has lots drawbacks such as excessive repetitious labors,heavy work- load and lack of optimixation,which are especially serious in NC programming for complex components of marine diesel.Based on the key technologies of applying KBE(Knowledge Based Engineering)to NC programming——knowledge representation,general- ized knowledge base,knowledge acquisition and knowledge reasoning,the system of intelligent NC programming for complex com- ponents of marine diesel has been built by means of the knowledge template and the UG/Open.The experiment results indicate that the NC program generated with high efficiency of NC programming by the system is accurate enough to meet the need of NC ma- chining.Consequently,the automatization and intelligentization of NC programming has been presented,and the study is proved to be a successful attempt in the area of applying KBE to NC programming.
  • . 2006, (S3):  165-168. 
    摘要 ( )   
    The first multi-function laser processing system in the domestic for clutch manufacture,with abilities of cutting, jointing and heat treatment,was reported in this paper.One external optical path,double laser heads,adjust device by manual operation,automatically track were employed in this system Also the other parts of vehicles can be fabricated by this system,as well as clutches.The special processing to manufacture the clutches of heavy vehicles,which was developed by the project of this laser processing system,achieved the international standards and satisfied the economic development and nation defense in the do- mestic.
  • . 2006, (S3):  169-174. 
    摘要 ( )   
    This paper is based on a resource constrained active network project;the constraint of the local resource and the time constraint of the cooperation resource are considered simultaneously.And the respective benefit of the manager and cooperation partners is also considered simultaneously.And a cooperation planning model based on bilevel multi-objective programming is de- signed,according to the due time and total cost.And an extended CNP based on the permitted range for resource and time requests is presented.A larger task set in scheduling cycle is on the permitting for the request of cooperation resource and time while the task manager itself may be permitted biding for tasks.As a result,the optimization space for the cooperation planning is enlarged.So not every bidding task is successfully bid by invitee,and the task manager itself takes on some bidding tasks.Finally,the genetic algorithm is given and the validity and feasibility of the model is proved by a case.
  • . 2006, (S3):  175-179. 
    摘要 ( )   
    In order to provide reliable data for the dynamic design or modification of a tool machine,the dynamic character- istics of the headstock,which is the main component to bear moment,must be obtained precisely.In the paper,the method based on the combination of calculation mode and experiment mode is proposed to analyze the dynamic characteristics of the headstock.The modal parameters and the mode shapes are calculated by ANSYS7.1 software.According to the FEM calculating results,the ex- periment parameters can be selected correctly.The modal parameters of the headstock have to be calculated and identified precisely. On the basis of these modal parameters,the faults of the headstock are shown and its weak points of design are illustrated.A con- clusion is drawn that some reasonable reinforce positions could greatly improve the dynamic characteristics of the system and this ap- proach is proved to be precise and reliable.
  • . 2006, (S3):  180-184. 
    摘要 ( )   
    T-S fuzzy model was applied to describe nonlinear system and global fuzzy model was expressed by the form of uncertain system.Based on robust state feedback H_∞control strategy,designed a global asymptotic steady fuzzy model.This control system can use the experimental input-output data pairs for the biped robot learning and walking with dynamic balance.It is proved by simulation result that robust state feedback H_∞control method based on T-S fuzzy model can effectively restrain the effect of model uncertainties and external disturbance acting on biped robot.From these works,we showed the satisfactory performance of joint tracking without any chattering.
  • . 2006, (S3):  185-190. 
    摘要 ( )   
    Motivated by industrial applications we study a single-machine scheduling problem in which all the jobs are mutu- ally independent and available at time zero.The machine processes the jobs sequentially and it is not idle if there is any job to be pro- cessed.The operation of each job cannot be interrupted.The machine cannot process more than one job at a time.A setup time is needed if the machine switches from one type of job to another.The objective is to find an optimal schedule with the minimal total jobs'completion time.While the sum of jobs'processing time is always a constant,the objective is to minimize the sum of setup times.Ant colony optimization(ACO)is a meta-heuristic that has recently been applied to scheduling problem.In this paper we propose an improved ACO-Branching Ant Colony with Dynamic Perturbation(DPBAC)algorithm for the single-machine schedul- ing problem.DPBAC improves traditional ACO in following aspects:introducing Branching Method to choose starting points;im- proving state transition rules;introducing Mutation Method to shorten tours;improving pheromone updating rules and introduc- ing Conditional Dynamic Perturbation Strategy.Computational results show that DPBAC algorithm is superior to the traditional ACO algorithm.
  • . 2006, (S3):  191-197. 
    摘要 ( )   
    The coordinating control system is popular used in power plant.This paper describes the advanced coordinating control by control methods and optimal operation,introduces their principals and features by using the examples of power plant op- eration.It is wealthy for automation application in optimal power plant operation.
  • . 2006, (S3):  198-202. 
    摘要 ( )   
    There has been some research on the theory of QFD(Quality Function Deployment)and FMEA(Failure Modes and Effect Analysis)recently,but little work to the integrated system of QFD and FMEA development.This paper analyses the technical difficulties of realization of QFD and proposes away using computer-supported collaborative work to develop the integrated system of QFD and FMEA and how to do it.The way can make the system more efficient and more suitable to new requirements of networked manufacturing enterprise.The same time,prototype system of the integrated system is developed by comprehensively ap- plication of Java、JSP、JavaServlet,the open World Wide Web platforms of which enhances the communication function,improves the group cooperation and shorts the development time.The system is verified reasonably and reliably through the example of QFD analysis of some automobile.
  • . 2006, (S3):  203-206. 
    摘要 ( )   
    Digital design and optimal are very important in modern design.The traditional design methods and procedure are not fit for the modern missile weapons research and development.Digital design methods and optimal ideas were employed to deal with this problem.The disadvantages of the traditional missile's airframe design procedure and the advantages of the digital design methods were discussed.A new concept of design process reengineering(DPR)was put forward.An integrated missile air- frame digital design platform and the digital design procedure,which integrated the optimization ideas and methods,were devel- oped.Case study showed that the design platform and the design procedure could improve the efficiency and quality of missile's airframe design,and get the more reasonable and optimal results.
  • . 2006, (S3):  207-211. 
    摘要 ( )   
    In many industrial,it is often necessary to analyze the engine assembly.This paper introduces three kinds of new technologies on the assembly line of engine in recent years,it have played the positive role in improving the quality of assembling.
  • . 2006, (S3):  212-217. 
    摘要 ( )   
    This paper studies the kinematic modeling of a mobile manipulator that consists of 5-DOF manipulator and an autonomous wheeled mobile platform.Then an artificial neural network to realize the coordination motion between manipulator and mobile platform is developed.On the basis of the task specifications,the algorithm determines the appropriate control variables to respond to the well tracking trajectory.The control strategy employed for either subsystem is achieved by using a robust supervised controller.A learning paradigm is used to produce the required reference variables for an overall cooperative behavior of the sys- tem.Simulation results are presented to show the effectiveness of this approach.
  • . 2006, (S3):  218-222. 
    摘要 ( )   
    A product data management system for a manufacturing enterprise is to make sure that the proper product data can be communicated to the right people at the right time.This paper describes a system analysis paradigm for data analysis in a product data management(PDM)development.Three aspects of the paradigm,i.e.,function,structure and behavior are rep- resented.The use of the paradigm explains why so many kinds of objects are necessary in a commercial database matrix and what models are available for developing a PDM application.As another result,a lot of models are derived from the analysis of product data system paradigm to model product data and PDM database definitions.
  • . 2006, (S3):  223-227. 
    摘要 ( )   
    In CNC machining,the complexity of the part contour causes a series of problems including the repeated start-stop of the motor,low machining efficiency,and poor machining quality.To relieve those problems,a new interpolation algorithm was put forward to realize the interpolation control of continuous sections trajectory.The relevant error analysis of the algorithm was also studied.The feasibility of the algorithm was proved by machining experiment using a laser machine to carve the interpola- tion trajectory in the CNC system GT100.This algorithm effectively improved the machining efficiency and the contour quality.
  • . 2006, (S3):  228-231. 
    摘要 ( )   
    With Visual C++6.0 as the language,following the traditional waterfall model and the software engineering theory,utilizing the technique of the dialog box,picture synthesis in VC,the writers present the developing of the woven fabric CAD system under the environment of Windows98.The system includes weave designing,yarn simulating,color matching,han- dling hand sample fabric and the testing effect. The basic methods and effect evaluation have been discussed and developed for the weave designing,yarn appearance simulat- ing and fabric color matching,as well as handling hand sample states the image processing,such as DIB(Device-independent bitmap);meanwhile,the developed system has been tested and run in actual design and textile mill trials.The operated results show that the system runs steadily,efficiently and smart,it can be widely used in yarn and fabric design by using with the merits of convenience,celerity and nicety in shortening the developing periods of product;additionally,it provides in fact a new ap- proach to technical design for textile mills.
  • . 2006, (S3):  232-235. 
    摘要 ( )   
    First,the constitution of traditional visual sensor is presented.The linear camera model is introduced and the transform matrix between the image coordinate system and the world coordinate system is established.The basic principle of camera calibration is expatiated based on the linear camera model. On the basis of a detailed analysis of camera model,a new-style visual sensor for measurement is advanced.It can realize the real time control of the zoom of camera lens by step motor according to the size of objects.Moreover,re-calibration could be avoided and the transform matrix can be acquired by calculating,which can greatly simplify camera calibration process and save the time. Clearer images are gained,so the measurement system precision could be greatly improved.The basic structure of the visual sensor zoom is introduced,including the constitute mode and the movement rule of the fixed former part,zoom part,compensatory part and the fixed latter port.The realization method of zoom controlled by step motor is introduced. Finally,the constitution of the new-style visual sensor is introduced,including hardware and software.The hardware system is composed by manual zoom,CCD camera,image card,gearing,step motor,step motor driver and computer.The realization of software is introduced,including the composed module of software and the workflow of measurement system in the form of structured block diagram.
  • . 2006, (S3):  236-240. 
    摘要 ( )   
    Information exchange platform(IEP)for port logistics is used to realize data transmission among different sys- tems and districts by Internet.This paper presents the web services technology used in transferring information for port logistics. The system architecture based on J2EE and B/S mode frame has been constructed to subscribe the distributed information.To en- sure platform independent,extensible markup language(XML)integration technology was also used in the system design.
  • . 2006, (S3):  241-244. 
    摘要 ( )   
    This paper presents the model of one-tire kinetics、tires、the braking system and the model of control system.On virtual road,this paper builds a fuzzy predictive control system to insure the best attachment coefficient between tires and road. And it turns out to be that this fuzzy predictive control method has achieved good performances.
  • . 2006, (S3):  245-248. 
    摘要 ( )   
    When producing special-shape spring in CNC spring coiler,the setup of the coiler is often a manual work using a trial-and-error method.As a result,the setup of coiler consumes so much time and becomes the bottleneck of the spring production process.In order to cope with this situation,this paper proposes an automatic generation system of setup for CNC spring coiler us- ing case-based reasoning(CBR).The core of the study contains:(1)integrated reasoning model of CBR system;(2)spatial shape describe of special-shape spring based on feature;(3)coiling case representation using shape feature matrix;and(4)case similari- ty measure algorithm.The automatic generation system has implemented with C++Builder 6.0 and is helpful in improving the automaticity and efficiency of spring coiler.
  • . 2006, (S3):  249-253. 
    摘要 ( )   
    Considering grinding a cam with numerical control(NC)cam grinder,a mathematical model should be estab- lished with the unified parameter based on the original cam-lobe lift data to describe the movement of wheel and establish the relation between the wheel center coordinate,the measuring angle and workpiece's spindle rotation angle.By analyzing,the grinding wheel can be regarded as different followers.To the planar and roller followers,different mathematical models are established, but they can be unified in Eqs.(17)of this paper with the different value of the roller radius r_1.And also the model is suit for the edged follower when assuming the roller radius r_1=0.Experimental verification was done with TKM120 CNC/CBN grinder with NC sets' interpolation according to the model,which shows that high precision parts can be manufactured and this mathemat- ical model can be practically applied for NC cam grinder.
  • . 2006, (S3):  254-259. 
    摘要 ( )   
    To decrease thermal stress during laser metal deposition shaping(LMDS)process,it is of great importance to learn the transient thermal stress distribution regularities.Based on the“element life and death”technique of finite element analy- sis(FEA),a three-dimensional multi-track and multi-layer numerical simulation model for LMDS is developed with ANSYS parametric design language(APDL)for the first time,in which long-edge parallel reciprocating scanning paths is introduced. Through the model,detailed simulations of thermal stress during whole metal cladding process are conducted,the generation and distribution regularities of thermal stress are also discussed in detail.Using the same process parameters,the simulation results show good agreement with the features of samples which fabricated by LMDS.
  • . 2006, (S3):  260-264. 
    摘要 ( )   
    In order to realize the uniform knowledge representation including STEP and SGML,aimed at the defects of cur- rent methods,a new semantic model that is named XOEM+OWL is put forward.And then the correspondent mapping between STEP Schema Graph and OWL Schema Graph are build as Cos(sc,oc),so we can get the semantic pattern matching degree for the semantic representation on the product information.At last the example is presented.
  • . 2006, (S3):  265-270. 
    摘要 ( )   
    Anomaly detection and recognition are of prime importance in process industries.Faults are usually rare,and, therefore,predicting them is difficult.In this paper,a new greedy initialization method for the K-means algorithm is proposed to improve traditional K-means clustering techniques.The new initialization method tries to choose suitable initial points,which are well separated and have the potential to form high-quality clusters.Based on the clustering result of historical disqualification product data in manufacturing process which generated by the Improved-K-means algorithm,a prediction model which is used to detect and recognize the abnormal trend of the quality problems is constructed.This simple and robust alarm-system architecture for predicting incoming faults realizes the transition of quality problems from diagnosis afterward to prevention beforehand indeed.In the end,the alarm model was applied for prediction and avoidance of gear-wheel assembly faults at a gear-plant.
  • . 2006, (S3):  271-274. 
    摘要 ( )   
    The early impulse fault diagnosis of the gearbox in rolling mills is often difficult and labour intensive because the gearbox of that high speed machine is multi-shafting transmission system,in which many gearsets and rolling bears work together at the same time and there are much complex frequency structure and various disturb.A new time-frequency method based on the wavelet packets technique was developed and used to extract the impact feature from signals collected from faulty data of one rolling mills gearbox.The method improves the signal to noise ration so that results obtained using this method represents features with fine resolution in both low-frequency and the high frequency bands.The results of analysis indicate the validity and the practicability of the method proposed here.
  • . 2006, (S3):  275-280. 
    摘要 ( )   
    By introducing Rough Set Theory and the principle of Support vector machine,a gear fault diagnosis method based on them is proposed.Firstly,diagnostic decision-making is reduced based on rough set theory,and the noise and redundancy in the sample are removed,then,according to the chosen reduction,a support vector machine multi-classifier is designed for gear fault diagnosis.Therefore,SVM'training data can be reduced and running speed can quicken.Test shows its accuracy and effi- ciency of gear fault diagnosis.
  • . 2006, (S3):  281-287. 
    摘要 ( )   
    Generally complex 3D contours are divided into a lot of continuous small line blocks by CAD/CAM software. When these small line blocks are used in conventional way,machine tool has to stop at the end of one move before continuing on to the next to meet accuracy requirement,which results in inefficiency.Look-ahead is an intelligent function that aims at adjusting the feed rate automatically to achieve maximum productivity while maintaining accuracy.By now most researchers just utilize the simplest linear acceleration(ACC)and deceleration(DEC)to deal with look-ahead intelligence.A generalized ACC/DEC ap- proach and corresponding optimal look-ahead algorithm based on dynamic back tracking along a doubly linked list are proposed.An improved rounding strategy for reducing interpolation errors is also presented.By using the proposed techniques,arbitrary velocity profiles that offer look-ahead feature and have the desired ACC/DEC characteristics for movement of a lot of continuous line blocks can be generated efficiently.Both simulations and experiments showed the productivity was dramatically increased without sacri- fice of accuracy.
  • . 2006, (S3):  288-292. 
    摘要 ( )   
    This paper discusses not a point of equilibrium to free system,but a certain family of equilibrium state of dynami- cal system with inputs.This equilibrium state depends on the input,so it is called the dynamic equilibrium state.The expression of the dynamic equilibrium state can be given under some certain condition.With deductions and proofs in linear control system,es- tablish the expression of the dynamic equilibrium state in two cases,where the linear systems are nonsingular or singular.Also pre- sent the concept and the condition of the controllability of the dynamic equilibrium state.The controllability of the dynamic equilib- rium state is different from the controllability of the state to system,but these two are closely related.
  • . 2006, (S3):  293-296. 
    摘要 ( )   
    In order to improve the satisfaction degree of customers'individual demands for products and reduce the risk of the product innovation,the characteristics of customer demands for product innovation are analyzed,and the type and content of customer demands are discussed.Then the framework of customer demands acquisition for product innovation is established.Final- ly,the prototype system of customer demands information acquisition and product customization for product innovation which takes mobile phone as the example is developed successfully.
  • . 2006, (S3):  297-299. 
    摘要 ( )   
    The intelligent controlling and data process of pitch error measurement is proposed.The whole system takes C~(++) as the development tool and takes advantages of object-oriented and visualization,having the advantages of easy operation and hu- manistic interface.In the meanwhile,the system can be complemented and improved according to the demand of user,having cer- tain independence.The research of the system provides an efficient and reliable way to measure and analyze the gear pitch,which can be referenced in the future research.
  • . 2006, (S3):  300-305. 
    摘要 ( )   
    The performance measurement of enterprise technology alliances is complex.In this article,evaluation mechanism of entropy has been applied to it.Above all,performance connotation of enterprise technology alliance is defined from the aspect of self-organizatlon theory.Then,on dynamic and systerna-tical view,an entropy-based overall performance measurement model for technology alliance is established,using its life-cycle as the principal line,which includes initial condition evaluation,process e- valuation as well as benefit evaluation.Finally,a case study is carried out to the demonstration of that model.The author believes that an improved performance measurement model based on alliance life-cycle would be practicability to alliance.
  • . 2006, (S3):  306-309. 
    摘要 ( )   
    Computer aided process planning system played a key role for integrating design and manufacturing or assembly systems properly considering available resources and design constraints.To take advantage of the enterprise resource,the web CAPP framework was established.Case based reasoning and multi agent system were integrated in the system.The multi agent mecha- nism was discussed in the paper.And an instance of case base was introduced.They made the system run independently and contin- uously in the network environment of process planning problems.
  • . 2006, (S3):  310-316. 
    摘要 ( )   
    The article simply describes the difficulties of the Mould and Die project control,and then put forward the thoughts of developing the Monitoring and Early Warning System for the Mould and Die manufacturing.Afterwards,the main three constructing principles and the goals of the system are explained carefully.Based on those,the theory and the classifications of the Monitoring and Early Warning are expounded.With the assistance of the use case diagram of UML(the United Modeling Language),the main functions of the system are analyzed;and with the activity diagram of the UML,the work flows of the monitoring and early warning are expressed clearly.Finally,the classes and the architectures of the system are designed by making use of the class diagram of UML.
  • . 2006, (S3):  317-321. 
    摘要 ( )   
    The computer aided process planning will certainly play a significant role in the success of enterprise information- ization.3-dimensional design will promote Tri-dimensional process planning.This article analysis nowadays situation and prob- lems of assembly process planning,gives a 3-dimensional computer aided process planning system(3D-VAPP),and researches on the product information extraction,assembly sequence and path planning in visual interactive assembly process design,dynamic emulation of assembly and process verification,assembly animation outputs and automatic exploding view generation,interactive craft filling and craft knowledge management,etc.It also gives a multi-layer collision detect and multi-perspective automatic camera switching algorithm.Experiments were done to ualidate the feasibility of such technology and algorithm,which established the foundation of tri-dimensional computer aided process planning.
  • . 2006, (S3):  322-325. 
    摘要 ( )   
    In this paper,we present a novel collision detection algorithm to real time detect the collisions of objects.We gen- erate sphere textures of objects,and use programmable graphics hardware to mapping texture and check the depth of different ob- jects to detect the collision.We have implemented the algorithm and compared it with CULLIDE.The result shows that our algo- rithm is more effective than CULLIDE and has fixed executive time to suit for real-time applications.
  • . 2006, (S3):  326-330. 
    摘要 ( )   
    The hardware and software design of two digital control systems based on 80C196KB MCU for flash butt welder is introduced in this paper.The welding power supply is made of six-phase half-wave rectifier.The welding outer characteristic of welding machine is realized by digital PI algorithm with the voltage close-loop feedback.The flashing curve is finished by elec- tric-hydraulic servo valve.The process control system transfers datum with power supply system by a serial communication inter- face.The parameters of the control systems are collected by photoelectrical seclusion to avoid the disturbing of the electromagnetism in welding process.
  • . 2006, (S3):  331-335. 
    摘要 ( )   
    The competition in 21st century will be the competition among different manufacturing chains.Manufacturing chain makes decision not only the core enterprise of the manufacturing chain but also a group of enterprises.Any significant decision in manufacturing chain will affect each enterprise in manufacturing chain,thus every significant decision should meet the desire and requests of each enterprise that be affected.Any significant decision should concentrate in the opinion of each member in the rep- resentative assembly or committee and obtain the authorization of the congress.Any vital question also should be discussed,made the decision and coordinated the moves by the representative assembly or the committee.With society's development and the technical progress,the knowledge and the information content is growing suddenly,the questions needs making the decision are more and complex,the single enterprise only depended on its own resources and the strength is unable to grasp all essential information,and hard to face all questions.The representative assembly formed by representatives from each enterprise in manufacturing chain can gather together experts of different knowledge structure and different experience,which make up the deficiency of single enterprise in resources,strength and experience with the aid of many enterprises'resources and the strength.This is not just increase several brains,but to establish an information complex to ensure the scientific of decision,which formed by different knowledge structure, applies scientific theory method and means,can mutually enlighten and has abundant knowledge.So it comes down to the group decision.Group decision questions have two types,one is the collectivity decision which pursue the holistic benefit of the group,the other is that the members in the group pursue its'own benefit and value against others,that means the game theory of interest con- flict existed among the members.Currently,most scholars research the questions in manufacturing chain from the point of game theory,the research on collectivity decision,which pursues the holistic benefit of manufacturing chain,is limited.The group deci- sion support systems used in the later stage of 1990s includes electronic conference system and working flow system.
  • . 2006, (S3):  336-339. 
    摘要 ( )   
    In this paper,the problem on the service platform,which existed on the traditional WEB application mode,are analyzed in detail.It shows that application of the AJAX technology can optimize the service platform.And the AJAX technology can supply the wonderful solution for the development of the high-performance WEB application by means of the WEB performance testing tool to test the network performance of the service platform.
  • . 2006, (S3):  340-345. 
    摘要 ( )   
    To improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping(LDMS),it is of great significance to understand the distribution regularities of transient temperature field during LDMS process.Based on the“el- ement birth and death”technique of finite element method,a three-dimensional multi-track and multi-layer model for the transient temperature field analysis of LDMS is developed by ANSYS Parametric Design Language(APDL)for the first time.In the fab- ricated modal,X-direction parallel reciprocating scanning paths is introduced.Using the same process parameters,the simulation results show good agreement with the microstructure features of samples which fabricated by LDMS.
  • . 2006, (S3):  346-349. 
    摘要 ( )   
    The deadlock-handling scheme is based on a bipartite graph model of the part-machine relationship in the manufac- turing cell.A distinction is made between permanent deadlock and transient deadlock.Permanent deadlock depicts a manufactur- ing system state where parts are irrevocably blocked and where external intervention is required to resolve the deadlock,whereas a transient deadlock indicates that there is a positive probability that the deadlock will resolve itself over time.To recover from dead- locks,one control policy is studied:resolve deadlocks in the manufacturing cell.Under the policy,it is shown that it is sufficient to resolve any cycle in the set of deadlocked parts to resolve the deadlock.Finally,we estimate the deadlocks in flexible manufactur- ing cells.
  • . 2006, (S3):  350-353. 
    摘要 ( )   
    This paper puts forward a new scheme of Embedded Numerical Control System based on ARM and DSP,which is at the base of research on traditional numerical control system and embedded technology.And the paper also describes the develop- ment of hardware and software platform.All the development and realization are based on the idea of module design.The embed- ded numerical control system,using ARM and DSP to construct the main control platform,realizes the real-time operation of sys- tem and improves the stability and reliability with the modular designing ideas of hardware and software and with the support of embedded real-time operating system(uc/os-Ⅱ).And the system could realize the multi-network supporting,which is also accord with the development of modularization,flexibility and latticing of numerical control system.
  • . 2006, (S3):  354-359. 
    摘要 ( )   
    Flexibility is the demand of management revolution,and also the milestone of management development.The flexible ERP system is the information system to orientate variety and handle uncertainties.The market with rapid change and agile manufacture need a flexible ERP system.The article elaborates the meanings and characteristics about flexibility,the flexibility of ERP and the flexible ERP system;it discussed the necessity,the possibility and the related condition of setting up the flexible ERP system;and puts forward the strategy and the approaches of setting up the flexible ERP system.
  • . 2006, (S3):  360-363. 
    摘要 ( )   
    The computer aided engineering is aiming at the numerical simulation-the important link in the advanced digital manufacturing.Its second development based on Ansys platform can be carried out often.In common,the Visual Basic and APDL are important development tools and are applied in the product design at the same time.In the paper,the secondary development flow and method based on Ansys is described.The parameter design and analysis process of the bridge girder erecting equipment is carried on with Ansys software and its secondary development tools—APDL and Visual Basics,including the interact between the mode of Ansys batch solving and Visual Basic.The method speeds up design and enhances the product the quality and the perfor- mance.
  • . 2006, (S3):  364-368. 
    摘要 ( )   
    In order to generate the digital gear tooth surfaces(DGTS)with high efficiency and high precision,a method for identification and compensation of machining errors is demonstrated in this paper.Machining errors are analyzed directly from the real tooth surfaces.The topography data of the part are off-line measured in the post-process.A comparison is made between two models:CAD model of DGTS and virtual model of the physical measured surface.And a matching rule is given to determine these two surfaces in an appropriate fashion.The developed error estimation model creates a point-to-point map of the real surface to the theoretical surface in the normal direction.A“pre-calibration error compensation”strategy is presented.Through processing the results of the first trail cutting,the total compensation error is predicted and an imaginary digital tooth surface is reconstructed. The machining errors in the final manufactured surfaces are minimized by generating this imaginary surface.An example of ma- chining 2-D DGTS verifies the developed method.The research is of important theoretical and practical value to manufacture the DGTS and other digital conjugate surfaces.
  • . 2006, (S3):  369-372. 
    摘要 ( )   
    Recently multi-agent system(MAS)is regarded as a powerful paradigm to develop and simulate complex system. Because supply chain(SC)is a complex network,it is hard to improve supply chain management(SCM)efficiency and automate SC operating process.Researchers have applied MAS in SCM viewing enterprises in SC as different functional agents collaborating to achieve common goal.In this paper a MAS-based supply chain management framework(MSF)is developed on which agents can collaborate to conduct business activities of enterprises and customers.Six kinds of functional agents are designed,namely, management agent,order receiving agent,order decomposing agent,resource agent,manufacturing-controlling agent and trans- portation agent.Through the agents' collaboration the MSF can support SC dynamic forming and operating process.For partner selection the method to transmit customers' order into demand matrix,and transmit enterprise's resource capacity into resource matrix is described in detail.The MSF users decide which algorithm to be applied in matching the two matrixes,and algorithms are stored in model base.Finally the generic agent architecture is put formard.
  • . 2006, (S3):  373-376. 
    摘要 ( )   
    A unified feature definition is proposed.Feature is form-concentrated,and can be used to model product func- tionalities,assembly relations,and part geometries.The feature model is given and a feature classification is introduced including functional,assembly,structural,and manufacturing features.A prototype modeling system is developed in Pro/ENGINEER that can define the assembly and user-defined form features.
  • . 2006, (S3):  377-381. 
    摘要 ( )   
    Computer numerical control(CNC)system is the base of modern digital and intelligent manufacturing technolo- gy.And opened its architecture and constituted based on PC and Windows operating system(OS)is the main trend of CNC sys- tem.However,even if the highest system priority is used in user mode,real-time capability of Windows(2000,NT,XP)for applications is not guaranteed.By using a device driver,which is running in kernel mode,the real time performance of Windows can be enhanced greatly.The acknowledgment performance of Windows to peripheral interrupts was evaluated.Harmonized with an intelligent real-time serial communication bus(RTSB),strict real-time performance can be achieved in Windows platform. An opened architecture software CNC system which is hardware independence is proposed based on PC and RTSB.A numerical control real time kernel(NCRTK),which is implemented as a device driver on Windows,is used to perform the NC tasks.Tasks are divided into real-time and non real-time.Real-time task is running in kernel mode and non real-time task is running in user mode.Data are exchanged between kernel and user mode by DMA and Windows Messages.
  • . 2006, (S3):  382-385. 
    摘要 ( )   
    The key to carry out ICAD technology is to establish the knowledge-based and wide rang of domains-covered product model.This paper put out a knowledge-based methodology of adaptive modeling.It is under the Ontology mind,using the Object- Oriented technology and being a knowledge-based model framework.It involves the diverse domains in product design and realizes the multi-domain modeling,embedding the relative information including standards,regulars and expert experience.To test the feasibility of the methodology,the research bonds of the automotive diaphragm spring clutch design and an adaptive clutch design model is established,using the knowledge-based modeling language-AML.
  • . 2006, (S3):  386-389. 
    摘要 ( )   
    This paper describes the design of cement raw material prepared digital control system by PROFIBUS.It uses the digital technology to implement the digital control system for raw material prepared of the cement factory.This system improves the communication between the industrial system and locale instrument devices.It applies digital communication to replace ttle 4-20 mA or 24VDC signal between locale lever device and controller.
  • . 2006, (S3):  390-390. 
    摘要 ( )   
    1 Manuscripts,in triplicate and in English,should be submitted to one of the executive Editors or Editor in Chief.All contributions will be subject to critical review prior to acceptance and publication. 2 Submission is a representation that the manuscript has not been published previously and is not currently under consideration for publication elsewhere.