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1.
Pan Jinping 《计算机科学技术学报》1991,6(3):271-275
An automated environment is presented which aids the software engineers in developing data processing systems by using rapid prototyping techniques.The environment is being developed on VAX station.It can render good support to the specification of the requirements and the rapid creation of prototype.The goal,the methodology,the general structure of the environment and two sub-systems are discussed. 相似文献
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In many synchronous receivers, symbol timing synchronization is achieved through implementation of an analog phase locked loop (PLL). A phase detector and voltage-controlled oscillator drive a reference signal to be in phase with the received training sequence. Due to the quick phase convergence this option is attractive; however, limitations in pre-packaged hardware make this approach infeasible at times. Changes in the received symbol rate in software radio applications can further complicate the hardware implementation by requiring additional control signals to alter the frequency of the reference signal. This paper examines a configurable symbol synchronizer for software-defined radio (SDR) architecture with a predefined RF front end. In this scenario, we implement a typical method for digital phase locking and make it adaptable to different data rates. A pre-synchronization step is used to provide a reasonable initial estimate for the received symbol period for lower, over-sampled data rates. This decreases the synchronization time while maintaining a constant sampling period at the ADC. It also maintains the down-conversion stage at the receiver. The paper shows the feasibility of this architecture to support wide range of symbol rates. 相似文献
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In recent years it has been noticed that rapid prototyping produces better software products. Research on combining Artificial Intelligence and software engineering has also been conducted for a number of years. A knowledge-based system for rapid prototyping is presented. In the system, the Frame-and-Rule Oriented Requirements Language and a methodology are developed to provide an integrated means of prototyping throughoyt the software life cycle. The particular application domain to be modelled is represented in terms of objects and activities. FRORL, which uses the concept of frames and production systems, describes the problem domain's objects and activities in a natural way. With the support of a knowledge base, a software prototype can be rapidly developed using FRORL. The system has been implemented using Prolog on a VAX-11/780 computer. 相似文献
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Many applications, for instance, in the reverse engineering and cultural heritage field, require building a physical replica of 3D digital models. Recent 3D printers can easily perform this task in a relatively short time and using color to reproduce object textures. However, the finite resolution of printers and, most of all, some peculiar optical and physical properties of the used materials reduce their perceptual quality. The contribution of this paper is a shape enhancing technique which allows users to increase readability of the tiniest details in physical replicas, without requiring manual post-reproduction interventions. 相似文献
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提出了一种基于RTLinux快速控制原型平台,能在复杂控制系统设计中,缩短产品的设计时间,降低成本.进一步提高系统的可靠性.给出了整个平台的实现方法,介绍了Matlab/Simulink在快速控制原型中的应用和数据采集卡设备驱动的实现方法,使用HEPTANE对任务的最坏情况下任务执行时间分析,借助TrueTime对系统任务的可调度性进行验证.结合液压机控制系统,验证了提出方法的有效性. 相似文献
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Artificial Intelligence (AI) is defining the future of next-generation infrastructures as proactive and data-driven systems. AI-empowered radio systems are replacing the existing command and control radio networks due to their intelligence and capabilities to adapt to the radio environmental infrastructures that include intelligent networks, smart cities and AV/VR enabled factory premises or localities. An efficient resource prediction framework (ERPF) is proposed to provide proactive knowledge about the availability of radio resources in such software-defined heterogeneous radio environmental infrastructures (SD-HREIs). That prior information enables the coexistence of radio users in SD-HREIs. In a proposed framework, the radio activity is measured in both the unlicensed bands that include 2.4 and 5 GHz, respectively. The clustering algorithms k- means and DBSCAN are implemented to segregate the already measured radioactivity as signal (radio occupancy) and noise (radio opportunity). Machine learning techniques CNN and LRN are then trained and tested using the segregated data to predict the radio occupancy and radio opportunity in SD-HREIs. Finally, the performance of CNN and LRN is validated using the cross-validation metrics. 相似文献
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An evaluation of three software engineering tools based on their use in research and educational environments is presented. The three testing tools are Mothra, a mutation-testing tool, Asset, a dataflow testing tool, and ATAC, a dataflow testing tool. Asset, ATAC, and Mothra were used in research projects that examined relative and general fault-detection effectiveness of testing methods, how good a test set is after functional testing based on program specification, how reliability estimates from existing models vary with the testing method used, and how improved coverage affects reliability. Students used ATAC and Mothra by treating the tools as artifacts and studying them from the point of view of documentation, coding style, and possible enhancements, solving simple problems given during testing lectures, and conducting experiments that supported ongoing research in software testing and reliability. The strengths, weaknesses, and performances of Asset, Mothra, and ATAC are discussed 相似文献
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Wafer-scale integration architecture for rapid prototyping (WARP), a generalized architecture for rapid prototyping, is discussed. The primary goal of rapid prototyping is to map one of several members of a class of algorithms using a single-wafer architecture. The wafer can be personalized for the algorithm by either soft or hard-restructuring. The WARP wafer consists of an array of two types of cells specifically defined for this architecture: the universal multiply-subtract-add (UMSA) cell and the universal nonlinear (UNL) cell. Reconfiguration of the algorithms in the presence of defects, a harvesting probability model and yield, and wafer-scale testing and test facilities are described 相似文献
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《Science of Computer Programming》1987,9(2):179-205
Logic programming has great potential for reducing the cost of software development. We argue that, with an appropriate programming methodology, a logic programming system provides a powerful tool for rapid software prototyping. It is sufficiently formal and high-level to allow reasoning about specifications, and it provides an immediate operational validation of the programmer's intuitions.The methodology is introduced by means of an example larger than those usually used to illustrate the advantages of logic programming. We start with an informal specification of a structure-editor, show how it is formalized into a directly executable prototype, and introduce guidelines for validating logic programming code as implemented in Prolog.The developed prototype can be used for a number of applications: syntax-directed editor, semantic network browser, etc. The editor is compact but readable, and is quite efficient. 相似文献
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基于USB3.0的GPP软件无线电系统的硬件平台设计 总被引:1,自引:1,他引:0
针对基于通用处理器(GPP)的软件无线电(SDR)系统的基带数据传输问题,提出了一种基于USB3.0接口的WCDMA软件无线电系统的硬件平台。基于WCDMA系统的要求,选择了USB3.0控制器、FPGA和DDRII组成的硬件平台,最终实现了WCDMA系统基带数据的高吞吐率、低延时传输,并验证了USB3.0技术在WCDMA系统中应用的可行性。实验结果表明,在基于USB3.0的GPP软件无线电系统中,USB3.0的接口速率能达到200 Mb/s,系统的回环延迟时间为0.7 ms左右,能够满足WCDMA系统的需求。 相似文献
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《Robotics and Autonomous Systems》2006,54(6):486-495
In this paper, we present an architecture for rapid prototyping of visual controllers based on standard off-the-shelf hardware and software. The proposed scheme allows control of a wide class of systems including robot manipulators and underactuated systems using a digital camera. The graphical programming environment is based on MatLab/Simulink© which allows us to take advantage of Simulink graphic programming facilities. Experiments are presented to evaluate the proposed architecture. 相似文献
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Surface roughness visualisation for rapid prototyping models 总被引:1,自引:0,他引:1
When considering the use of rapid prototyping (RP), there are many questions a designer might ask. One such question is “what build orientation should be used to minimise the adverse effects of surface roughness?” At present, this decision is often made in an intuitive way or sometimes overlooked completely. This paper describes a methodology and software implementation that provides the designer with a computer graphics based visualisation of RP model surface roughness. This enables the build orientation to be determined as a result of increased designer knowledge. The surface roughness values were obtained through an extensive empirical investigation of several RP techniques. These are used as the database for a visualisation algorithm that represents varying surface roughness of the RP model as colour shading within a CAD image. The nature of the empirical measurements is analysed and the functionality of the software algorithm is described. Examples are given that demonstrate the use and benefits of the methodology. Finally, conclusions are drawn as to the significance of the work and future research directions are outlined. 相似文献
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NURBS-based adaptive slicing for efficient rapid prototyping 总被引:4,自引:0,他引:4
Weiyin Ma Author Vitae 《Computer aided design》2004,36(13):1309-1325
This paper presents slicing algorithms for efficient model prototyping. The algorithms directly operate upon a non-uniform rational B-spline surface model. An adaptive slicing algorithm is developed to obtain an accurate and smooth part surface. A selective hatching strategy is employed to further reduce the build time by solidifying the kernel regions of a part with the maximum allowable thick layers while solidifying the skin areas with adaptive thin layers to obtain the required surface accuracy. In addition, it provides a generalization to the containment problem with mixed tolerances for slicing a part. The article also developed a direct method for computing skin contours for all tolerance requirements. Some case studies are presented to illustrate the developed algorithms and the selective hatching and adaptive slicing strategy. The developed algorithms have been implemented and tested on a fused deposition modeling rapid prototyping machine. Both the implementation and test results are discussed in the paper. 相似文献
16.
《Computer Graphics and Applications, IEEE》1995,15(3):8-11
Virtual reality has sparked many people's imaginations, but writing VR programs remains difficult. Besides the obvious problems of managing arcane I/O devices (trackers, gloves, and so on), the programs must allow the participant to operate effectively in the immersive environment. Virtual environments present a new medium for both the participant and the programmer/author. In the University of Virginia's User Interface Group, we believe the best way to accelerate development in a new medium such as VR is to provide tools that allow people without highly technical backgrounds to create programs for it. These novice authors must be able to quickly try different nuances of an idea. They must be able to easily ask “what if” questions. To support this goal, we are developing Alice, a rapid prototyping environment that can generate VR environments. The name “Alice” honors Lewis Carroll's heroine, who explored a rapidly changing, dynamic environment 相似文献
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Tools for rapid prototyping in the biosciences 总被引:2,自引:0,他引:2
Modeling natural objects like human skeletons is essentially reverse engineering from medical imaging data. We report on the design and implementation of such tools for computer-assisted rapid prototyping applications. Two application case studies show how graphics tools exploit the potential of stereolithography in the biosciences, demonstrating the role of stereolithographic models (a) in reconstructing fragmentary fossil skulls and (b) in surgical planning and rehearsal 相似文献
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Integrated reverse engineering and rapid prototyping 总被引:16,自引:0,他引:16
Reverse engineering is a methodology for constructing CAD models of physical parts by digitizing an existing part, creating a computer model and then using it to manufacture the component. When a digitized part is to be manufactured by means of rapid prototyping machines such as stereolithography apparatus (SLA) and selective laser sintering equipments (SLS), etc., it is not necessary to construct the CAD model of a digitized part. This will be described by the proposed novel method which can construct STL file (the de facto file format for rapid prototyping machines) directly from digitized part data. Further more, the STL file can even be constructed in a way that significant data reduction can be achieved at the users' discretion. 相似文献
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To reduce the time and cost of moulds fabrication, a novel integrated developing and manufacturing system of rapid tooling (RT) based on rapid prototyping (RP) is proposed. The architecture of system which consists of four building blocks: digital prototype, virtual prototype (VP), physical prototype and RT system, is presented. A digital prototype can be established by 3D CAD software packages or reveres engineering technique. A VP is employed to guide in optimization of the mould design and manufacturing process planning. A physical prototype, which is built using RP technology, generally serves as a pattern for producing RT. By integrating these building blocks closely, the system can aid effectively in mould design, analysis, prototyping, simulating, and manufacturing process development. Three typical cases are discussed in detail to illustrate the application of the system. It has been shown from a number of case studies that the system has a high potential to reduce further the cycle and cost of die development while minimizing error introduction. As a result, the integrated system provides a feasible and useful tool for companies to speed up their product development. 相似文献
20.
《Parallel Computing》2002,28(7-8):1179-1202