Showing papers on "Design tool published in 2003"

DENIM: an informal web site design tool inspired by observations of practice

Abstract: Through a study of Web site design practice, we observed that designers employ multiple representations of Web sites as they progress through the design process and that these representations allow them to focus on different aspects of the design. In particular, we observed that Web site designers focus their design efforts at 3 different levels of granularity--site map, storyboard, and individual page--and that designers sketch at all levels during the early stages of design. Sketching on paper is especially important during the early phases of a project, when designers wish to explore many design possibilities quickly without focusing on low-level details. Existing Web design tools do not support such exploration tasks well, nor do they adequately integrate multiple site representations. Informed by these observations we developed DENIM: an informal Web site design tool that supports early phase information and navigation design of Web sites. It supports sketching input, allows design at different levels of granularity, and unifies the levels through zooming. Designers are able to interact with their sketched designs as if in a Web browser, thus allowing rapid creation and exploration of interactive prototypes. Based on an evaluation with professional designers as well as usage feedback from users who have downloaded DENIM from the Internet, we have made numerous improvements to the system and have received many positive reactions from designers who would like to use a system like DENIM in their work.

Method and apparatus for building an application interface

Abstract: Embodiments of the invention comprise a design tool for designing an application interface. The design tool includes a graphical user interface (GUI) that visually represents a hierarchy of data and the relationships between the data. Thus, the design tool eliminates the need for an interface designer to have independent knowledge of the structure of the data (i.e., the data fields and relationships between the data). The design tool's GUI represents the data and the relationships between the data in a hierarchical display referred to as a data palette. An output hierarchy comprised of output levels is created as the user selects fields from the data palette to be displayed in the application's interface. When a data field is selected, the design tool automatically determines the appropriate interface component and output level of the output hierarchy using the relationships defined for the data. Output levels are associated with interface components that comprise the application's interface. Examples of interface components that can be used in the application's interface include a form, view and subband.

Are informal tools better?: comparing DEMAIS, pencil and paper, and authorware for early multimedia design

Abstract: DEMAIS is an informal design tool that we claim helps a multimedia designer explore and communicate temporal and interactive (behavioral) design ideas better than existing tools. This paper seeks to empirically validate our claim. We report on an evaluation comparing DEMAIS to pencil and paper and Authorware for the exploration and communication of behavior in early multimedia design. The main results are that (i) DEMAIS was better than Authorware for both exploring and communicating behavior, (ii) DEMAIS was better than pencil and paper for communicating behavior, and (iii) DEMAIS was able to capture most of a designer's behavioral design ideas. Our results show that DEMAIS bridges the early investment/communication gap that exists among current multimedia design tools.

Structured ASICs: opportunities and challenges

Abstract: There is currently a huge gap between the two main technologies used to implement custom digital integrated circuit (IC) designs. At one end of the spectrum are field programmable gate arrays (FPGAs). These devices have relatively low design costs and short design times, but they also have high per-unit costs and are limited in terms of design size, complexity, and performance. At the other end of the device continuum are application specific integrated circuits (ASICs). These components have exceedingly high design costs and take a long time to develop, but they can support extremely large, complex, and high-performance designs, and they have low per-unit costs in large production runs. A new category of devices-known as structured ASICs-is now becoming available. These devices bridge the gap between FPGAs and ASICs in terms of cost and capabilities, but they also pose challenges to device manufacturers and design tool vendors.

A design tool for camera-based interaction

Abstract: Cameras provide an appealing new input medium for interaction. The creation of camera-based interfaces is outside the skill-set of most programmers and completely beyond the skills of most interface designers. Image Processing with Crayons is a tool for creating new camera-based interfaces using a simple painting metaphor. A transparent layers model is used to present the designer with all of the necessary information. Traditional machine learning algorithms have been modified to accommodate the rapid response time required of an interactive design tool.

Perturbation analysis for word-length optimization

Abstract: This paper introduces a design tool and its associated procedures for determining the sensitivity of outputs in a digital signal processing design to small errors introduced by rounding or truncation of internal variables. The proposed approach can be applied to both linear and nonlinear designs. By analyzing the resulting sensitivity values, the proposed procedure is able to determine an appropriate distinct word-length for each internal variable. Also in this paper, the power optimizing capabilities of word-length optimization are studied for the first time. Application of the proposed procedure to adaptive filters realized in a Xilinx Virtex FPGA (field programmable gate array) has resulted in area reductions of up to 80% combined with power reductions of up to 98% and speed-up of up to 36% over common alternative design strategies.

On the role played by turbulence closures in hull shape optimization at model and full scale

Abstract: The practical use of automated computational fluid dynamics (CFD)-based design tools in the ship-building industry requires powerful flow solvers which are able to take into account realistic geometries as well as complex physical phenomena, such as turbulence. A shape optimization tool is developed in this framework. A derivative-free optimizer, yielding both flexibility and robustness, is preferred to the classical gradient-based method, which is more difficult to implement and is still limited to only moderately complex problems. The flow solver included in the design procedure solves the incompressible Reynolds-averaged Navier–Stokes equations on unstructured grids using a finite-volume formulation involving several near-wall low-Reynolds-number turbulence models. The design tool is used to optimize the stern of a modern hull shape at model and full scale, with different purposes being considered. More precisely, the drag reduction and the homogenization of the flow in the wake are expected by controlling the longitudinal vortex generated. Our interest is particularly focused on the influence of turbulence modeling in the design process. The effects of a two-equation model based on the eddy-viscosity assumption and a second-order closure relying on the Reynolds stress transport equations are compared.

Design of closed-loop input shaping controllers

Abstract: Input shaping/time delay prefilter are techniques for robust vibration control of slewing flexible structures. These are open-loop schemes and cannot handle uncertain initial conditions and effects of disturbances. In this paper, we develop a technique for the design of closed loop input shapers and illustrate it on a simple benchmark problem. A range of uncertainties over which the system remains stable is determined and is used as a design tool. It should be noted that the structure of the controller is similar to internal mode control (IMC).

Multi-Objective Optimization of Communication Satellites with Two-Branch Tournament Genetic Algorithm

Abstract: In spacecraft design, many specialized state-of-the-art design tools are employed to optimize the performance of various subsystems. However, there is no structured system-level concept-definition process. Consequently, designers usually compromise some mission goals to satisfy only one of the primary design objectives. The conceptual stage of the spacecraft design process is formulated into a multi-objective discrete optimization problem. The use of multi-objective design allows the designer to evaluate different design alternatives across the whole set of design objectives. This work addresses two key design objectives for the spacecraft design process: the minimization of total launch mass and the maximization of spacecraft overall reliability. To predict values for the objective and constraint functions, a satellite design tool, which includes a satellite sizing model and a deterministic reliability model, was built and integrated with a genetic algorithm that employs a two-branch tournament to address the dual objective problem. The multi-objective approach was successful in determining sets of discrete design parameters that would minimize the launch mass as well as maximize the reliability of a geostationary communication satellite, using specified payload requirements. The designs generated by this approach appear to fall into three regions of the tradeoff space between the satellite launch mass and the satellite reliability objectives.

System-level simulation modeling with MLDesigner

Abstract: System-level design presents special simulation modeling challenges. System-level models address the architectural and functional performance of complex systems. Systems are decomposed into a series of interacting sub-systems. Architectures define subsystems, the interconnections between subsystems and contention for shared resources. Functions define the input and output behavior of subsystems. Mission-level studies explore system performance in the context of mission-level scenarios. This paper demonstrates a variety of complex system simulation models ranging from a mission-level, satellite-based air traffic management system to a RISC processor built with MLDesigner, a system-level design tool. All of the case studies demonstrate system-level design techniques using discrete event simulation.

Finite-element method programming made easy???

Abstract: the finite-element method has become a common tool in the computational electromagneticist's toolbox over the past decade. During the decade of the 1990s, the method has evolved from an interesting approach with great promise for modeling structures that are difficult to model using competing methods, such as integral equation-based approaches, to a mainstream, commercially viable design tool. Although there are a number of excellent commercial finite-element-based design environments, it is still instructive for finite-element novices to write their own programs as an aid in understanding the potential, and limitations, of the method. Writing your own - albeit simple and limited - finite-element program will facilitate better understanding of how to make the most of the excellent commercial programs now on the market. This paper outlines various textbook and online sources of content that facilitates such a voyage of discovery.

Enhancing Virtual Product Representations for Advanced Design Repository Systems

Abstract: This paper describes the transformation of an existing set of heterogeneous product knowledge into a coherent design repository that supports product design knowledge archival and web-based search, display, and design model and tool generation. Guided by design theory, existing product information was analyzed and compared against desired outputs to ascertain what information management structure was needed to produce design resources pertinent to the design process. Several test products were catalogued to determine what information was essential without being redundant in representation. This set allowed for the creation of a novel single point of entry application for product information and the development of a relational database for design knowledge archival. Web services were then implemented to support design knowledge retrieval through search, browse, and real-time design tool generation. Further explored in this paper are the fundamental enabling technologies of the design repository system. Additionally, repository-generated design tools are scrutinized alongside human-generated design tools for validation. Through this process researchers have been able to improve the way in which artifact data are gathered, archived, distributed and used.

Experimental Validation of an Integrated Controls-Structures Design Methodology for a Class of Flexible Space Structures

Abstract: This paper describes the first experimental validation of an optimization-based integrated controls-structures design methodology for a class of flexible space structures. The Controls-Structures-Interaction (CSI) Evolutionary Model, a laboratory testbed at Langley, is redesigned based on the integrated design methodology with two different dissipative control strategies. The redesigned structure is fabricated, assembled in the laboratory, and experimentally compared with the original test structure. Design guides are proposed and used in the integrated design process to ensure that the resulting structure can be fabricated. Experimental results indicate that the integrated design requires 60 percent less average control power (by thruster actuators) than the conventional control-optimized design while maintaining the required line-of-sight performance, thereby confirming the analytical findings about the superiority of the integrated design methodology. Amenability of the integrated design structure to other control strategies is considered and evaluated analytically and experimentally. This work also demonstrates the capabilities of the Langley-developed design tool CSI-DESIGN, which provides a unified environment for structural and control design.

Use and Adaptation of Precedents in Architectural Design: Toward an Evolutionary Design Model

Abstract: For centuries, architects have re-used design precedents in the conception of new design solutions. Whether explicitly - as in the case of Le Corbusier, James Stirling and Jo Coenen - or implicitly - as with J.J.P. Oud, Aldo van Eyk, and Santiago Calatrava - this practice has led to very advantageous efficient, effective, and innovative results. The goal of this research project is to contribute to the construction of computational tools to facilitate this practice by developing a model that grasps significant characteristics of the design process as it employs precedents. The model is built drawing an analogy from the natural evolution. The intention is not to represent the processes that take place in the architects minds but rather their behavior as this is manifested in their design products. The project draws from the multidisciplinary methodology of design tool development of the Design Knowledge Systems Research Center. It employs an analogy with Darwinian evolutionary theory in combination with recent theories of genetics and embryology. The criteria of usefulness in picturing the phenomenon in architecture determines the focus on particular aspects of the analogy. The research also uses three case studies from the architectural domain: J.J.P. Oud, to identify adequacy criteria for the model; Le Corbusier, to illustrate the components and conduct of the model under development; and Santiago Calatrava, to test the model. The research develops a pre-computational qualitative model that provides insights into the process of re-use and adequacy criteria for an analytical model to succeed in architectural practice. Given the notorious history of misuse of analogies from the Darwinian model and biological models in general to other fields, special attention was paid to circumscribe the limits of the analogy. There are basic differences between design and evolutionary models, the most important being the process of selection, natural versus artificial. As "breeders", designers recall from memory and/or from archives through "artificial selection" - this is not the case in natural selection. In natural evolution, mutations are "random", and natural selection gives the direction. In the human design process, mutations and selection are mostly intentional. Many analogies suffer from confusion between the natural science notion of evolution and the cultural notion of progress; they are also highly reductive in their representation of cognitive processes of design, misrepresenting the design process. The evolutionary and genetics analogy serve as heuristic devices to represent the mechanisms in the process of use and adaptation of design precedents and the elements of such precedents accumulated over the years that are adapted and recombined during the design process often leading to design innovations. The model employs the notion of "design feature", a precedent component, as the most important unit of selection. Drawing from developmental genetics, and the idea of regulatory genes, each feature is derived from two interlinked kind of instructions where the "regulatory d-gene" deals with the configurational instructions and the "structural d-gene" deals with the technique and materials used. In the design model, just as in evolution, the notion of fitting environmental constraints in the generation of form is essential. Fitness relates to both internal and external constraints; it is multi-dimensional in a multi-criteria ecological environment.

Extending CRC cards into a complete design process

Abstract: Ectropic Design is a feature-oriented, collaborative design method, patterned on Open Source software development. Software evolves ectropically through the continuous augmentation of its features, which are bound to specific program goals. These evolving features are defined in terms of the end-user goals the features achieve and how the features interact, both statically and dynamically, with other features. By binding source code and collaboration technology to identified program goals, Ectropic Design provides developers with the necessary mechanisms to enhance software continuously, while maintaining the conceptual integrity of the program.Ectropic Design is taught as a part of our curriculum's Sophomore required course on Objects and Desig. In the course, we introduce students to CRC cards (Class, Responsibility, Collaborator cards) and scenarios. Traditionally, CRC cards are simply 3x5 index cards, one for each class being considered in a design, annotated with two columns: One for the responsibilities of that class, and the other with the collaborators that the class will need to complete the responsibilities. Scenarios are narrative descriptions of how the system being designed should respond to user-initated events.We have students understand enjoy, and actually use CRC cards in the introductory object-oriented design process. We attempted to teach a more sophisticated design process that would grow upon the students' interest in CRC Cards, and we provided a design tool to support that process. The Ectropic Collaborative Design Environment, ECoDE, is a development tool designed to capture CRC Cards and Scenarios, and it provides a natural mechanism for tying these two design notions to the underlying code the students were writing.The results of using ECode in the class were not as promising as we had hoped. Students did develop much better scenarios than they had in the past, but they did not use the ties to code at all. More importantly, students found that ECoDE actually stifled their collaborations: With current computer monitors, it's much easier to gather around a table full of 3x5 cards than a screen of graphical index cards.Students expressed frustration in having to learn how to use ECoDE, and indicated that they were more comfortable with pencil and paper. An important indicator of the usability of ECoDE was the decision of the student whether to use ECoDE for the final two design submissions ---for it they were free to choose not to use ECoDE. It is interesting to note that 68.5% of the students voluntarily chose to use ECoDE. The top reason given for choosing to use ECoDE was its simplicity in updating their previous design versions. Of the students who chose not to use ECoDE, the reason most frequently given was that they preferred pencil and paper (44%). Subjectively, the subject group documentation was much more detailed in nature. Many of the subject group students demonstrated a clearer personal understanding of their actual design.A high level conclusion of our study could be, "Beginning students will not willingly use a detailed design process", but that is a little too simplistic. The students did appreciate CRC cards and willingly used them. They did also use some of the aspects of the Ectropic Design process, such as the emphasis on scenarios. But simply putting things in a computer tool does not make them better. Student's primary goal is the completion of the program, not the design. The limitations of a one semester course makes it difficult to make it otherwise. It is the challenge of educators to build design tools that will be adopted that meet that goal. Studying ECode has given us some insight on how best to proceed to meet that challenge.

Procedural analog design (PAD) tool

Abstract: This paper presents a new procedural analog design tool called PAD. It is a chart-based design environment dedicated to the design of analog circuits aiming to optimise design and quality by finding good tradeoffs. This interactive tool allows step-by-step design of analog cells by using guidelines for each analog topology. At each step, the user modifies interactively one subset of design parameters and observes the effect on other circuit parameters. At the end, an optimised design is ready for simulation (verification and fine-tuning). Furthermore, PAD provides a layout generator for matched substructures such as current mirror, cascode stage, differential pair, etc. The analog basic structures calculator embedded in PAD uses the complete set of equations of the EKV MOS model, which links the equations for weak and strong inversion in a continuous way. The present version of PAD covers the procedural design of transconductance amplifiers (OTAs) and different operational amplifiers topologies.

The development of a theoretical framework and design tool for process usability assessment.

Abstract: The purpose of usability engineering is to facilitate the deployment of new products by decreasing development costs and improving the quality of systems. This paper will discuss the development and delivery of a unique, theoretically based software tool that provides engineers and designers with easy access to the most recent advances in human-machine interface design. This research combines several theoretical views of the interaction process into a hybrid model. Based on this model, a software tool was produced that allows engineers to model the human interaction process within their design. The system then provides feedback on the interaction process through items such as: the amount of mental effort required by a user, the degree to which the system conforms to human capabilities, the expected time to complete the interaction, where potential human error may occur, as well as potential misunderstandings or points of confusion to the users. The designer may then use this information to improve the design of the system. Validation of this technique indicates that the hybrid model produces accurate predictions of usability attributes and that the technique transfers from the laboratory to the real world.

Automated machine component design tool

Abstract: A system and method for designing a machine component is provided. A plurality of requirements associated with the machine component are established. A component layout is automatically established in response to the plurality of requirements. The component layout is analyzed to determine whether the component layout meets a predetermined performance threshold. A final component design is established when the component layout meets the predetermined performance threshold. The system and method may further compare the component layout with a set of information related to existing machine components and identify an existing machine component that has a similar layout to the component layout. In addition, the system and method may determine the costs associated with the component layout and identify changes in the component layout to reduce the costs associated with the component layout. In addition, the method provides the opportunity to capture and implement design or analysis method improvements.

A transformer-like model for the DC/AC converter

Abstract: The paper proposes a two-port model of the inverter leg as building block to simulate the various topologies of switched-mode DC/AC converters, overcoming the problems encountered with the usual switch-diode simulation approach while retaining the interaction between the AC and DC sides The model has a simple transformer-like formulation, easy to implement in any circuit simulation environment, and allows the lossless behavior, the conduction losses and the switching losses to be separately modeled Using the same set of few parameters, it can be implemented in three different versions, from the most general to the simplest one, to be selected according to the application and to the accuracy requirements A simplified expression for the load of the DC source is also derived allowing ready determination of DC operating point that is crucial to the efficiency of non-conventional power sources As design tool, the proposed model has proved to be accurate and effective in predicting the behavior of a system, as can be seen from the application example reported in the paper, and it is very useful to dimension the power devices heatsink In research and education areas, it also help to give physical insight into the converter operation and design criteria

Apparatus and method for synthesizing and designing circuits and filters

Abstract: An apparatus is provided for designing a filter to be rendered on a programmable circuit device capable of realizing at least one filter design by wiring together at least one filter component. The apparatus includes a programmable computing device, a user interface, and a design tool. The user interface is associated with the programmable computing device. The design tool is associated with the programmable computing device and is configured for interaction with a user at the user interface. The design tool comprises computer program code embodied in the programmable computing device including at least one filter sub-circuit definition for rendering a filter design and containing information for defining at least one of multiple configurations, topologies, and parameters of the filter design via the at least one sub-circuit definition for a programmable circuit device. The user interface is configured to enable a user to select and apply input parameters to the filter design and dynamically receive display of at least one of filter response, poles required, and evaluation of sub-circuit parameters so a user can optimize input parameters for a desired filter design. A method is also provided.

A design tool for operator- adaptive steering controllers

Abstract: One of the major deterrents of designing a control system for interactive use with an operator is the lack of a systematic procedure for modeling and incorporating human behavior directly into the design process In many cases, direct operator feedback is difficult for qualitative design without a costly, full–scale physical prototype The objective of this article is to present a modular framework, known as virtual design tools, to design the electrohydraulic steering system of off–road vehicles The aim was to adapt the electromechanical interface between the operator’s command signal and the fixed control and dynamic systems The adaptation was performed with the intent of modifying the system performance to be more acceptable to the operator without altering the control system or vehicular components This conceptual design tool was studied via a computer simulation for designing an operator–adaptive steering controller for an articulated off–road vehicle The simulation results indicated that this “operator–in–the–loop” design method could successfully incorporate human behavior in the controller design process using the virtual design tool

Web-based IP evaluation and distribution using applets

Abstract: This paper introduces an IP evaluation and delivery framework that operates within Java applets. The use of such applets allows circuit designers to create, evaluate, test, and obtain FPGA circuits directly within a Web browser. Based on the JHDL design tool, these applets allow structural viewing, circuit simulation, and netlist generation of application-specific circuits. An important component of this framework is the ability to deliver black-box simulation models as executable Java applets. These applet-based simulation models can be tied to third-party simulation tools using network sockets. Several techniques for interfacing black-box applet models to external simulators are described.

Derivation of circuit block constraints

Abstract: A design tool for generating circuit block constraints from a design environment. The design tool derives a fan-in cone function for each block input of a circuit block of a design. The fan-in cone function may include fan-in cone variables and block input variables. The fan-in cone functions are conjoined into a circuit block constraint functions. The circuit block constraint function is quantified to provide circuit block constraints. These constraints may be used in design verification (e.g. equivalence checking) and/or circuit analysis (e.g. timing rule generation).

An integrated design software for photovoltaic systems

Abstract: This paper describes the features of the PV system integrated evaluation software (PVI) developed by the authors. "PVI" was developed to assist in the design of grid-connected PV system applications and consists of a main tool and three optional tools. The main tool is the basic design tool. This tool is used to determine the PV system output energy based on the loss percentage of the PV system. The proportion of losses is based on development data calculated by the evaluation method developed at our Lab., "the sophisticated verification (SV) method". This method allows the user to feedback the performance of existing systems performance and loss pattern information to new PV system design projects. "PVI" has also three optional tools. The main optional tool is a PV array simulation tool. This tool is available for estimating annual, monthly or daily output power of PV arrays with different azimuth and orientation for the maximum of four surfaces at the same time. This simulation model calculates output power from I-V characteristic, considering effects of irradiance, ambient temperature, module rating, and so on. The other optional tool is for shading analysis that evaluates shading problems based on fish-eye lens pictures. This tool enables the user to determine the shading losses at the PV system under complex conditions. Additionally, PVI is able to input the database of SV method. The database includes the total design factor, which is analyzed data of existing PV systems.

Amdb: A Design Tool for Access Methods

Abstract: Designing and tuning access methods (AMs) has always been more of a black art than a rigorous discipline, with performance assessments being mostly reduced to presenting aggregate runtime or I/O numbers. This paper presents amdb, a comprehensive graphical design tool for AMs that are constructed on top of the Generalized Search Tree abstraction. At the core of amdb lies an an analysis framework for AMs that defines performance metrics that are more useful than traditional summary numbers and thereby allow the AM designer to detect and isolate deficiencies in an AM design. Amdb complements the analysis framework with visualization and debugging functionality, allowing the AM designer to investigate the source of those deficiencies that were brought to light with the help of the performance metrics. Several AM design projects undertaken at U.C.Berkeley have confirmed the usefulness of theion. At the core of amdb lies an an analysis framework for AMs that defines performance metrics that are more useful than traditional summary numbers and thereby allow the AM designer to detect and isolate deficiencies in an AM design. Amdb complements the analysis framework with visualization and debugging functionality, allowing the AM designer to investigate the source of those deficiencies that were brought to light with the help of the performance metrics. Several AM design projects undertaken at U.C.Berkeley have confirmed the usefulness of the analysis framework and its integration with visualization facilities in amdb. The analysis process that produces the performance metrics is fully automated and takes a workload—a tree and a set of queries—as input; the metrics characterize the performance of each query as well as that of the tree structure. Central to the framework is the use of the optimal behavior—which can be approximated relatively efficiently—as a point of reference against which the actual observed performance is compared. The framework applies to most balanced tree-structured AMs and is not restricted to particular types of of data or queries.