CAD of ECM tools

The last two decades have witnessed a rapid development in the application of electrochemical machining (ECM) techniques in production industries. However, there are tool design problems which hinder its application. Available analytical methods for the design of ECM tools do not yield satisfactory results.

In this paper, the finite-element technique is used which has proved superior to all other techniques. Also, details are given of the method employed for the computation of metal removal and gap in ECM. Relevant computer programs are included.     

CAD tools for aesthetic engineering

The role of computers and of computer-aided design tools for the creation of geometrical shapes that will be judged primarily by aesthetic considerations is reviewed. Examples are the procedural generation of abstract geometrical sculpture or the shape optimization of constrained curves and surfaces with some global ‘cost’ functional. Different possibilities for such ‘beauty functionals’ are discussed. Moreover, rapid prototyping tools based on layered manufacturing now add a new dimension to the visualization of emerging designs. Finally, true interactivity of the CAD tools allows a more effective exploration of larger parts of the design space and can thereby result in an actual amplification of the creative process.     

CAD of worms and their machining tools

To develop high-quality products, geometric modeling is needed in gear engineering to calculate the workpiece and tool geometry of worms, threads, or similar mechanical elements that can be described by helical or rotatory surfaces and that are to be generated by milling, grinding, or whirling. A survey will be given on the theoretical background, corresponding procedures, and illustrating examples of application concerning: (a) design of gear or worm profiles by means of curve primitives, their motion and manipulation; (b) calculation of conjugate gear profiles subjected to trochoidal motion; (c) calculation of arbitrary plane intersections of helicoids; and (d) calculation of the rotatory machining tool surface for a given worm and the inverse problem, including the solution of the undercut problem. Basic to the achieved integrated approach to CAD/CAM in this field is a discrete curve representation as sequence of points, tangent lines, and osculating circles providing higher geometrical information about curve and surface shape, which is also of high functional and economical importance for technological decisions.     

CAD tools for bridging microsystems and foundries

To move microsystems from research prototypes to an industrial market, CMP, the French multiproject wafer service, has adapted an existing commercial tool to the automated design of micromachined devices     

Fault injection techniques and tools

Fault injection is important to evaluating the dependability of computer systems. Researchers and engineers have created many novel methods to inject faults, which can be implemented in both hardware and software. The contrast between the hardware and software methods lies mainly in the fault injection points they can access, the cost and the level of perturbation. Hardware methods can inject faults into chip pins and internal components, such as combinational circuits and registers that are not software-addressable. On the other hand, software methods are convenient for directly producing changes at the software-state level. Thus, we use hardware methods to evaluate low-level error detection and masking mechanisms, and software methods to test higher level mechanisms. Software methods are less expensive, but they also incur a higher perturbation overhead because they execute software on the target system     

Integrating CAD tools for MEMS design

Microelectromechanical systems, or MEMS, is the generic name for a new class of microsystems. Typically, MEMS are: micron- to millimeter-scale devices with moving parts or containing fluids; parts that are batch fabricated using techniques derived from the semiconductor industry; used as sensors or actuators; and are often directly connected or integrated with ICs. The first MEMS design system, MEMCAD, was built in the Senturia Lab at MIT. Now at least three companies market commercial CAD systems for MEMS. The author discusses MEMCAD system's capabilities     

Multiresolution modeling techniques in CAD

This paper investigates new wavelet-based multiresolution modeling techniques in CAD. Models in the system are represented by endpoint-interpolating B-spline functions. Wavelet deformation techniques are extended to include synthesis editing and detail blending from previous sweep editing and fractional editing methods. Application of multiresolution editing to multiple patches of complex topology is investigated. An algorithm for multi-patch deformation is developed by enforcement of G⁰ continuity between adjacent patches. After editing G¹ continuity may be recaptured by numerical optimization of the error vectors along boundary seams. A simple CAD interface is implemented for B-spline patch acquisition based on reverse engineered data and layer based modeling and a moving cursor plane is used for three-dimensional (3D) editing. Design examples are presented to illustrate the 3D wavelet editing capability. The developed wavelet deformation techniques can be a useful complement to current CAD systems by providing powerful new modeling and editing capabilities.     

Extending process automation systems with multi-agent techniques

This paper presents a design of a process automation system extended with multi-agent systems (MAS) and experiments with its implementation. According to this design, MAS can be used to extend the functionality of ordinary process automation systems at higher levels of control. Anticipated benefits of this include enhanced reconfigurability, responsiveness and flexibility of the resulting automation system. The design also takes into account particular characteristics of process automation. An agent platform for process automation is presented as a basis for applying MAS. A FIPA-compliant agent platform is extended with process automation specific functionality. The platform utilizes a hierarchical agent organization and a BDI-agent model. Two applications are implemented using the platform. One of these shows how the techniques of distributed planning can be applied in discrete control. The other provides a model for supervisory continuous control using the techniques of distributed search. Experiments performed with a laboratory test environment using the applications are presented. They are able to demonstrate the feasibility of the approach in test scenarios.     

Improving time-to-market using SDL tools and techniques

In this paper we summarize our experiences in building and integrating new generation, formal-methods based computer aided software engineering tools (CASE) to yield pragmatic improvements in software engineering processes in the telecommunication industry. We define an accelerated development methodology (ADM) for the specification, design, testing and re-engineering of telecommunications software. We identify two of the most significant barriers to adoption of tools and formal methods to speed up software development, namely the requirements engineering barrier and the legacy code re-engineering barrier, and show how the ADM methodology helps to overcome these barriers and improve time-to-market for telecommunications software.Our ADM methodology is based on the most widely accepted formal languages standardized by the International Telecommunications Union (ITU):

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This paper emphasizes the following key components of our ADM methodology and their placement within the most common software engineering processes:

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Advanced tools and techniques for automatic parallelization

This paper describes some of the tools and techniques that are being used in the interactive SUPRENUM parallelization system SUPERB. Emphasis is placed on specific problems arising from the interactive nature of the system, in particular the necessity to incrementally update data flow information that is used to determine the applicability and the effect of transformations.     

Integrating techniques and tools for testing automation

This article presents two tools to generate test cases, one for Java programs and one for .NET programs, as well as a structured testing process whereby such tools can be used in order to help in process automation. The main innovation in this work is the joint use of diverse techniques and technologies, which have been separately applied to test automation: reflection to extract the class structure; regular expressions to describe test templates and test cases; JUnit and NUnit as test case execution frameworks; mutation and MuJava as test case quality measurers; serialization to deal with the parameters of complex data types; and once more, reflection, to facilitate the test engineer in the task of writing the oracle. Finally, the article presents an experiment carried out to validate the work. Copyright © 2006 John Wiley & Sons, Ltd.     

Design of asynchronous circuits using synchronous CAD tools

Poor CAD support hinders wide acceptance of asynchronous methodologies, and asynchronous design tools are far behind synchronous commercial tools. A new design flow, NCL_X, based entirely on commercial CAD tools, targets a subclass of asynchronous circuits called null convention logic. NCL_X shows significant area improvement over other flows for this subclass     

New multiresolution modeling techniques in CAD

To apply wavelet transformation to CAD surface model composed of multiple surface patches, an algorithm called wavelet signal separation to preserve geometric constraints during wavelet transformation is proposed. The algorithm divides the B-spline control points into those associated and those unassociated with the geometric constraints. Through preserving the signal information associated with the constraint control points, the geometric constraints can be automatically preserved after wavelet transformation. This paper also briefly investigates two types of the detail feature propagation technique in wavelet-based multiresolution CAD system. One is detail feature motion. The other is detail feature repetition. Finally, a comprehensive example is presented to illustrate the effects of the combination of those techniques.     

软件安全静态检测技术与工具

提出了一种软件安全漏洞的检测方法,重点介绍了静态测试.对当前基于源码分析的软件安全测试工具进行了分类并加以分析.     

An object-oriented program shell for integrating CAD software tools

The number of CAD programs and their capabilities have risen greatly in recent times. As well, the number of Application Programmer Interface (API) products and the number of representation standards for display, database storage and communication has also risen. These applications, API products and representation standards are generally not compatible except through specific, individually programmed interfaces. Incompatibility of API software products arises because of: (i) different representations for the same information, and (ii) different ways of communicating with the API products. This article describes the derivation of a generic software architecture to overcome the second source of incompatibility. The derivation employs the “box structure” (system engineering) software development methodology in a generic, high level manner; by considering activities performed with current CAD software, but without going into the details. The objective is to determine the types of software objects required and the types of messages that must be passed between them. The result is an architecture in which Tool objects embodying individual software tools are plugged into a Shell object which holds the Tool’s together as a single program, provides for interactions between Tool’s and controls when each Tool is active. In this way separately developed software tools can be combined seamlessly into a highly graphical and interactive environment.     

Developing CAD techniques for preliminary architectural design

Theoretically the computer can offer the architect significant help during the preliminary design stages. To take full benefit of its capabilities it is necessary to use the computer for the design process itself. To this end, a program has been written that concentrates on ease of use so that the machine does not impede the creative process. The program works through the manipulation of design elements such as spaces and windows, not graphical ones. The result is a tool which offers improved efficiency, but is very different from current methods that use paper in preliminary design.