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1.
In product design, the designer must draw upon many different types of information including both product-user requirements and design developments in related fields. As each designer has his/her own subjective opinion, an appropriate link between the user requirements and design features must be carefully developed to generate the most suitable design recommendation.The objective of this research is to develop a component design approach for the generation and evaluation of feasible design alternatives to help designers make the most effective design decisions. The development of the approach is based on the concept of component design and interaction links between user requirements and design output parameter values so that the design alternatives can be generated. A confidence interval for order statistics is then used to determine if enough unique feasible design alternatives have been generated. The research is presented in conjunction with a ballpoint pen design to demonstrate the feasibility and advantages of this approach.The results should provide designers with a useful method for the development of a design information system that will efficiently generate and evaluate a set of feasible design alternatives in product design process.  相似文献   

2.
Abstract— As thin‐film‐transistor liquid‐crystal‐display (TFT‐LCD) panels become larger and provide higher resolution, the propagation delay of the row and column lines, the voltage modulation of Vcom, and the response time of the liquid crystal affect the display images now more than in the past. It is more important to understand the electrical characteristics of TFT‐LCD panels these days. There are several commercial products that simulate the electrical and optical performance of TFT‐LCDs. Most of the simulators are made for panel designers. However, this research is for circuit, system, and panel designers. It is made in a SPICE and Cadence environment as a commercial circuit‐design tool. For circuit and system designers, it will help to design the circuit around a new driving method. Also, it can be easily modified for every situation. It also gives panel designers design concepts. This paper describes the electrical model of a 15‐in. XGA (1024 × 768) TFT‐LCD panel. The parasitic resistance and capacitance of the panel are obtained by 3‐D simulation of a subpixel. The accuracy of these data is verified by the measured values of an actual panel. The developed panel simulation platform, the equivalent circuit of a 1 5‐in. XGA panel, is simulated by HSPICE. The results of simulation are compared with those of experiment, according to changing the width of the OE signal. The proposed simulation platform for modeling TFT‐LCD panels can be especially applied to large‐sized LCD TVs. It can help panel and circuit designers to verify their ideas without making actual panels and circuits.  相似文献   

3.
Crucial issues for product designers include how to capture consumers’ attention, evoke their pleasurable preferences, and affect their purchase decisions. In this article, we focus on consumers’ affective preferences in relation to visual ergonomics to propose a new hybrid consumer‐oriented model using gray relational analysis (GRA), gray prediction (GP), and the technique for order preference by similarity to ideal solution (TOPSIS). The GRA is used to identify the most influential elements of the product form to help product designers focus their attention more on these elements without compromising the predictive performance. The GP is used in conjunction with the GRA to obtain a better structure for the hybrid consumer‐oriented model, and TOPSIS is performed to determine the optimal alternatives for best matching consumers’ affective preferences. These experimental results show that the new hybrid consumer‐oriented model incorporated with the CAD/CAM system can facilitate the product affective design process.  相似文献   

4.
Abstract— Positively doped, intrinsic, negatively doped organic light‐emitting diodes (PIN‐OLEDs) have been shown to exhibit high efficiency and a long lifetime compared to conventional small‐molecule OLEDs (SM‐OLEDs). The improved performance of PIN‐OLEDs makes them attractive for use in display applications. Knowledge of the electrical load exhibited by these devices is used to develop an equivalent electrical‐circuit model. Such models are used by circuit designers to assist with the precise design of active‐matrix‐display driver circuits used in such applications. In this paper, the development of a SPICE model for a top‐emitting PIN‐OLED stack is reported.  相似文献   

5.
Jia Zhang  Jen‐Yao Chung 《Software》2003,33(13):1251-1272
Web application development can be very complicated without an appropriate framework, architecture and application model. A good implementation model can help application developers communicate with clients, consolidate the design before starting the development, speed up the development, and make the code highly reusable. This paper proposes a mockup‐driven fast prototyping methodology (MODFM) for the development of Web applications. It is built on the most recent Web technologies: EJB, JSP, Servlet, XML, Struts, and Web application server. A two‐tier Model‐View‐Controller (MVC) architecture is proposed as the underlying backbone and a supporting environment is tailored specifically in order to enable development. Two basic supporting tools are provided: the dynamic menu generator and the generic code generator, which produce code for front‐end, back‐end and database schemas. MODFM helps to generate fully functional mockup systems for the client to review at an early analysis stage, and continues to provide guidance throughout follow‐on development phases. Real‐life experiences on the use of this methodology in industry are presented as examples. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

6.
This paper suggests a new miniaturized antenna for radio‐frequency identification (RFID) applications of 2.45 GHz. Our structure consists of a circular microstrip patch antenna which incorporates two concentric annular slots is printed on a multilayer substrates. The bandwidth, one of the most important characteristics of antenna, can be significantly improved by using a multilayer dielectric configuration. we aim by this study to show that the effect of radiating structure loaded by annular rings for the patch size reduction as well as the advantage of this structure being to create a circular polarisation in the direction of maximal radiation pattern. The wave concept iterative procedure is used to analyse this new antenna. Using the proposed procedure, less computing time and memory are needed to calculate the electromagnetic parameters of our design. The validation of the results of our developed model was verified with known commercial software called “CST Microwave Studio Software” followed by an experimental test. According to the reached results, we can judge that our new design antenna is suitable for RFID applications in the 2.45 GHz band.  相似文献   

7.
This paper presents an automated method to generate thin-walled packaging structures with reinforcement. This method first obtains a thin-walled design space compose of hexahedral elements, which covers the models to be packaged without undercut effect. After the proper boundary conditions are assigned by designers, topology optimization is applied to identify the optimal placement of reinforcement. This automated method can also be used to generate foam packaging structures. Design examples are presented to demonstrate the efficiency of this method.  相似文献   

8.
Ear anthropometry plays an important role in ear‐related product design. However, current Chinese ear anthropometry data do not provide sufficient guidance for product designers targeting young Chinese consumers. In this study, an ear anthropometry survey of 1338 young Chinese college students was conducted using photogrammetry. Eight key dimensions were determined, measured, and statistically analyzed: ear height, ear width, ear length, cavum conchae height, cavum conchae width, ear connection height, ear lobe height, and ear lobe width. Interethnic, intergender, subject‐specific, and intrasubject differences were explored and discussed, based on the collected data. In addition, ear shape classification was conducted using principal component analysis to recommend an ear‐related product sizing system. The data obtained in this survey can be used as a reference for ear‐related product design targeting young Chinese consumers.  相似文献   

9.
In this paper, a general and easy procedure for designing the symmetrical Wilkinson power divider that achieves equal‐power split at N arbitrary frequencies is introduced. Each quarter‐wave branch in the conventional Wilkinson divider is replaced by N sections of transmission lines, and the isolation between the output ports is achieved by using N resistors. The design parameters are the characteristic impedances and lengths of the N transmission line sections, and the N isolation resistors. The even–odd modes of analysis are used to derive the design equations. Closed‐form expressions, which are suitable for CAD purposes, are derived for the dual‐band divider. For N ≥ 3, closed‐form expressions are not available, and therefore, the powerful particle swarm optimization method is used to obtain the design parameters. Examples of the dual‐, triple‐, and quad‐band dividers are presented to validate the proposed design procedure, and the results are compared, wherever possible, with published results using other methods. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.  相似文献   

10.
The problem of electroplating selection has been of concern to users for many years. The selection process is becoming more and more difficult due to the availability of large variety of electroplating configurations and manufacturing plants/products. The methods proposed so far consider only physical parameters (thickness, hardness, adhesion, etc.). In order to have precise information about the selection process, the performance of electroplating plays a vital role.The objective of this paper is to propose a methodology by which selection of electroplating product/plant can be made easy. This selection procedure will help the user to select the system most suited for his operational needs. Moreover, the paper discusses how the electroplating suppliers, designers and maintenance personnel will also be benefited.The identification and codification of attributes based on n-digit alpha numeric code is presented here. The 3 stage selection procedure allows rapid convergence from a very large number of options to manageable shortlist of potentially suitable electroplating option using ‘elimination search’ based on a few pertinent attributes. Then the selection procedure ranks them by employing a multiple attributes decision making (MADM) method using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach. It helps the decision maker(s) to organize the problem to be solved, and carry out analysis, comparisons and ranking of the alternatives. Magnitudes of different attributes are used to generate parameters of the hypothetical ideal electroplating, with all the candidate electroplating compared and ranked. This ranking gives the best available electroplating for particular application. The methodology is presented with the help of illustrated example of gold plating, which shows that it can benefit the designers, users or manufacturers.  相似文献   

11.
Learning is a critical support mechanism for industrial and academic organizations to enhance the skills of employees and students and, consequently, the overall competitiveness in the new economy. The remarkable velocity and volatility of modern knowledge require novel learning methods offering additional features as efficiency, task relevance and personalization. Computational Intelligence methodologies can support e‐Learning system designers in two different aspects: (1) they represent the most suitable solution able to support learning content and activities, personalized to specific needs and influenced by specific preferences of the learner and (2) they assist designers with computationally efficient methods to develop “in time” e‐Learning environments. This article attempts to achieve both results by exploiting an ontological representations of learning environment and memetic approach of optimization, integrated into a cooperative distributed problem solving framework. This synergy enables multi‐island memetic approach managing a collection of models and processes for adapting an e‐Learning system to the learner expectations and to formulate objectives in an effective and dynamic intelligent way. More precisely, our proposal exploits ontological representations of learning environment and a memetic distributed problem‐solving approach to generate the best learning presentation and, at the same time, minimize the computational efforts necessary to compute optimal learning experiences.  相似文献   

12.
A wideband dual‐polarized microstrip antenna is presented. By designing the coplanar parasitic patches and modified feed probes, antenna profile is decreased significantly. Shorted pins are used and 34 dB isolation between input ports is then achieved. A phase difference feed network is introduced to suppress higher‐order modes and reduce the cross polarization to ?27 dB. To verify the design, a prototype of the antenna is fabricated and experimentally studied. Measured results show that 30.3% operating bandwidth (VSWR < 1.5) and good dual linear polarization characteristics with a profile height as low as 0.08λ are achieved. Due to the very compact configuration, the proposed antenna is suitable for micro‐base‐station applications.  相似文献   

13.
We demonstrate an implicit space mapping (ISM) method for microwave filter design that is enhanced and assisted by a tuning procedure. This procedure helps us to select design variables as well as suitable preassigned parameters for an ISM implementation. It also aids us in the convergence of our ISM algorithm. We investigated and solved a microstrip notch filter using this technique. This shows that tuning‐aided sensitivity analysis guides the parameter selections and enhances the performance of ISM optimization. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.  相似文献   

14.
A novel Antenna‐in‐Package with small size and low profile is designed based on Low Temperature Co‐fired Ceramic technology. In order to realize miniaturization and broadband in antenna part, a novel structure using double fractal antennas and air cavities is applied. A packaging cavity is designed for integrated with usable components and IC chips. The antenna operates at a center frequency of 2.4 GHz and the bandwidth is about 200 MHz. Its maximum gain is 5.6 dBi, and radiation efficiency is above 90% across the frequency passband. By adjusting the dimension parameters, a tradeoff between height and area can be made with its performance parameters constant, therefore the proposed Antenna‐in‐Package can easily adapt to different processes and performance.  相似文献   

15.
This paper presents a new technique to design fixed‐structure controllers for linear unknown systems using a set of measurements. In model‐based approaches, the measured data are used to identify a model of the plant for which a suitable controller can be designed. Due to the fact that real processes cannot be described perfectly by mathematical models, designing controllers using such models to guarantee some desired closed‐loop performance is a challenging task. Hence, a possible alternative to model‐based methods is to directly utilize the measured data in the design process. We propose an approach to designing structured controllers using a set of closed‐loop frequency‐domain data. The principle of such an approach is based on computing the parameters of a fixed‐order controller for which the closed‐loop frequency response fits a desired frequency response that describes some desired performance indices. This problem is formulated as an error minimization problem, which can be solved to find suitable values of the controller parameters. The main feature of the proposed control methodology is that it can be applied to stable and unstable plants. Additionally, the design process depends on a pre‐selected controller structure, which allows for the selection of low‐order controllers. An application of the proposed method to a DC servomotor system is presented to experimentally validate and demonstrate its efficacy.  相似文献   

16.
Many HCI products exclude potential users unnecessarily. Such exclusion often arises because of a mismatch between designers’ perceptions of the wants and needs of the end-user and their actual wants and needs. Sometimes the mismatch originates from the designer being unaware of the need to design inclusively, or of methods for implementing inclusive design. Other times the mismatch comes from the commissioner of the design, for example the client of a design consultancy. If the design commissioner specifies a target socio-economic group, but does not explicitly recognise that the group consists of users of varying functional capabilities, then the designers will often be given a design brief that overlooks the need to address the wider range of users, beyond simply the able-bodied. In either case, for universal access to be achieved effectively, information is required to identify the need for inclusive design and thus to generate demand, and design guidance is needed to help designers make inclusive design a reality. Currently, that information is largely unavailable to designers in an appropriate off-the-shelf format. This paper investigates methods for researchers to provide the kind of information that HCI designers need to design for universal access. It focuses on the profiling, recruitment and selection of users, along with the interpretation of the data gathered. In many instances, the HCI designer may also be the person performing the research, where specialist researchers are not available.  相似文献   

17.
The new generation of System‐on‐Chip (SoC) incorporates digital, analogue, RF/microwave and mixed‐signal components. Such circuits impose to reconsider the traditional design methods. Mixed‐signal designers need novel design methodologies which will have to include accurate behavioral libraries of devices and processes into hierarchical design flows. Thus, this paper describes a behavioral modeling approach which generates neuro‐fuzzy‐based models for RF/microwave devices. The models, so obtained, can be easily integrated into a VHDL‐AMS simulator. This modeling approach is applied to a microwave tunable phase shifter and it is illustrated by the development of a VHDL‐AMS model library for RF/microwave applications. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007.  相似文献   

18.
This article presents and discusses a unifying simulation procedure aimed at providing more realistic performance prediction of basic imaging systems, combining 3D EM (3 Dimensions Electro‐Magnetic) simulations and nonlinear receiver circuit simulation. New methods are proposed to emulate the radiated emissivity profile of a target body and to use harmonic balance simulation to emulate nonlinear circuit/system response to a broadband noisy stimulus. The procedure focuses mainly on passive imaging, but active imaging including illuminated passive imaging is dealt with and some elemental experiments are presented and discussed for comparisons. The method enables the extrapolation of the frequency response of a single pixel detector to an array with more elements suitable for providing a complete set of pixels and can help in evaluating the most suitable bandwidth according to the operation mode (passive/active), frequency range of operation, desired resolution, and the pixel number‐image resolution tradeoff.  相似文献   

19.
In this article we present a two‐stage Ku‐band low‐noise amplifier (LNA) using discrete pHEMT transistors on non‐PTFE substrates for low‐cost direct broadcast satellite (DBS) phased‐array systems (patent pending). The vertical input configuration of the LNA lends itself to direct integration with input port of antenna modules of the phased array, which minimizes preamplification losses. DC decoupling between LNA stages is realized using interdigital microstrip capacitors such that the implementation reduces the number of discrete microwave components and thereby not only reduces the component and assembly costs but also decreases the standard deviation of such crucial parameters of phased‐array systems as the end‐to‐end phase shift of the amplifier and the amplifier gain. Using the proposed printed decoupling capacitors, a cost reduction better than 30% of the original costs has been achieved. Additionally, we present a hybrid design procedure for the complete LNA, including its input and output connectors as well as packaging effects. This method is not based on parameter extraction, but encompasses electromagnetic (EM) field simulator results which are further combined using a high‐level circuit simulator. According to the presented measurement results, the implemented Ku‐band LNA has a noise figure better than 0.9 dB and a gain higher than 20 dB with a gain flatness of 0.3 dB over a 5% bandwidth. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006.  相似文献   

20.
Haoxue Ma  Tore Risch 《Software》2007,37(11):1193-1213
Timely and efficient information communication is a key factor in ensuring successful collaboration in engineering collaborative design. This work proposes a database approach to support information communication between distributed and autonomous CAD systems. It provides the designer with an easy and flexible way, a project‐based propagation meta‐table, to specify what parts of a CAD information model should be communicated to other collaborating designers. A CAD peer manager, containing a peer database that stores information to be exchanged with the other collaborators, wraps each participating CAD system. The peer manager identifies changes made to the CAD model by using stored procedures and active rules in the peer database that are automatically generated based on the propagation meta‐table. The identified updates are propagated in a timely manner to other peers via inter‐database message passing, thereby minimizing the volume of necessary information to be exchanged. Furthermore, remote peer designers can flexibly incorporate, filter, or delete received updates by using a propagation control interface, which is also used to issue user's commands to download the data from the CAD system to the peer database and lookup the received messages in the peer database. The approach is applicable on any CAD system having a CORBA interface and can also be applied to other kinds of object‐oriented interfaces. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

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