Tomonori Honda

A study of the role of user-centered design methods in design team projects

Abstract User-centered approaches to design can guide teams toward an understanding of users and aid teams in better posing design problems. This paper investigates the role of user-centered design approaches in design process and outcome within the context of design team projects. The value of interaction with users is examined at several stages throughout the design process. The influence of user-centered design on the performance of design teams is also explored. Results suggest that the quantity of interactions with users and time spent interacting with users alone is not linked with better design outcome, but that iterative evaluation of concepts by users may be of particular value to design prototypes. Suggestions are made based on the reflections from the authors after conducting this study.

A Study of Student Design Team Behaviors in Complex System Design

Large-scale engineering systems require design teams to balance complex sets of considerations using a wide range of design and decision-making skills. Formal, computational approaches for optimizing complex systems offer strategies for arriving at optimal solutions in situations where system integration and design optimization are well-formulated. However, observation of design practice suggests engineers may be poorly prepared for this type of design. Four graduate student teams completed a distributed, complex system design task. Analysis of the teams’ design histories suggests three categories of suboptimal approaches: global rather than local searches, optimizing individual design parameters separately, and sequential rather than concurrent optimization strategies. Teams focused strongly on individual subsystems rather than system-level optimization, and did not use the provided system gradient indicator to understand how changes in individual subsystems impacted the overall system. This suggests the need for curriculum to teach engineering students how to appropriately integrate systems as a whole. [DOI: 10.1115/1.4007840]

Graph Analysis for Detecting Fraud, Waste, and Abuse in Healthcare Data

Detection of fraud, waste, and abuse (FWA) is an important yet difficult problem. In this paper, we describe a system to detect suspicious activities in large healthcare claims datasets. Each healthcare dataset is viewed as a heterogeneous network of patients, doctors, pharmacies, and other entities. These networks can be large, with millions of patients, hundreds of thousands of doctors, and tens of thousands of pharmacies, for example. Graph analysis techniques are developed to find suspicious individuals, suspicious relationships between individuals, unusual changes over time, unusual geospatial dispersion, and anomalous networks within the overall graph structure. The system has been deployed on multiple sites and data sets, both government and commercial, to facilitate the work of FWA investigation analysts.

Approaches for Identifying Consumer Preferences for the Design of Technology Products: A Case Study of Residential Solar Panels

This thesis investigates ways to obtain consumer preferences for technology products to help designers identify the key attributes that contribute to a products market success. A case study of residential solar PV panels is conducted in the context of the California, USA market within the 2007-2011 time span. First, interviews are conducted with solar panel installers to gain a better understanding of the solar industry. Second, a revealed preference method is implemented using actual market data and technical specifications to extract preferences. The approach is explored with three machine learning methods: Artificial Neural Networks, Random Forest decision trees, and Gradient Boosted regression. Finally, a stated preference self-explicated survey is conducted, and the results using the two methods compared. Three common critical attributes are identified from a pool of 34 technical attributes: power warranty, panel efficiency, and time on market. From the survey, additional non-technical attributes are identified: panel manufacturers reputation, name recognition, and aesthetics. The work shows that a combination of revealed and stated preference methods may be valuable for identifying both technical and non-technical attributes to guide design priorities.

Connections Between the Design Tool, Design Attributes, and User Preferences in Early Stage Design

Gathering user feedback on provisional design concepts early in the design process has the potential to reduce time-to-market and create more satisfying products. Among the parameters that shape user response to a product, this paper investigates how design experts use sketches, physical prototypes, and computer-aided design (CAD) to generate and represent ideas, as well as how these tools are linked to design attributes and multiple measures of design quality. Eighteen expert designers individually addressed a two-hour design task using only sketches, foam prototypes, or CAD. It was found that prototyped designs were generated more quickly than those created using sketches or CAD. Analysis of 406 crowdsourced responses to the resulting designs showed that those created as prototypes were perceived as more novel, more aesthetically pleasing, and more comfortable to use. It was also found that designs perceived as more novel tended to fare poorly on all other measured qualities. Submitted to the Special Issue on “User Needs and Preferences in Engineering Design” MD-14-1619 | Yang | 3 INTRODUCTION The goal of product design and development is to create products that fulfill user needs so that consumers will desire and purchase them. In early stage design, design teams generate several design alternatives, then select among them to determine one to pursue for further development [1]. A user-centered strategy to help teams select a design direction is to elicit feedback from users and other stakeholders on provisional design concepts. The design team may then incorporate this feedback into future iterations of the design. This phenomenon of obtaining feedback on provisional design representations has become even more prevalent through the rise of online crowdfunding sites, such as Kickstarter, that present consumers with pre-production designs in order to attract financial investment. Low-cost, quick prototypes, known as “minimum viable product” designs, have been embraced by entrepreneurs as a means to pre-validate business ideas with potential customers [2]. A myriad of factors can play into a user’s responses to a provisional design, from the design’s functionality to its visual styling to the way in which a design is presented to the user. This study examines and compares two factors that can influence the way a user evaluates a design. First, this study considers the tools to create a provisional design during the exploratory, generative stage of the design process. A range of design tools may support the development of preliminary concepts, such as 2D sketches, 3D physical prototypes, Submitted to the Special Issue on “User Needs and Preferences in Engineering Design” MD-14-1619 | Yang | 4 and digital models, and may do so at different levels of fidelity – from rough representations to realistic renderings. Such tools have inherent capabilities and limitations, which means the same concept created using different tools can result in different designs and thereby potentially influence the feedback that users provide. For example, a preliminary design with complex curves that may be relatively fast and easy to sketch or shape from a piece of foam may be challenging to model using CAD. Moreover, the choice of design tool is in tension with the resources required to create the design representation. Generally, the higher the fidelity of the representation, the more skill and time required to create it. Higher fidelity representations may also require that the designer make additional decisions about design details in order to achieve the desired level of representation fidelity. Second, this study examines the attributes of the design itself, which may relate to the design’s functionality, interactions, appearance, and use, among others. Key product attributes are not only what users look for when making a purchase decision, but can characterize what it means to be an innovative product [3]. For example, gas mileage may be the most important attribute to a car buyer, while screen size may be an important determinant to someone selecting a mobile phone. This study investigates the interplay between the tools used by practitioners during preliminary design, a product’s attributes, and user evaluations of a design, and Submitted to the Special Issue on “User Needs and Preferences in Engineering Design” MD-14-1619 | Yang | 5 aims to uncover significant relationships among these using relative, rather than absolute, comparisons. The following research questions are framed: • How does the choice of design tool impact the rate of idea generation and the total number of ideas produced? • What is the relationship between the choice of design tool and how users evaluate a design based on its qualities? • What is the relationship between a product’s attributes and its perceived qualities? Are certain design attributes more, or less, strongly linked to specific product qualities? • What is the interplay of the tools used to create a preliminary design and the attributes of the resulting designs?

Representation in Early Stage Design: An Analysis of the Influence of Sketching and Prototyping in Design Projects

Sketching and prototyping of design concepts have long been valued as tools to support productive early stage design. This study investigates previous findings about the interplay between the use and timing of use of such design tools. This study evaluates such tools in the context of team design projects. General trends and statistically significant results about “sketchstorming” and prototyping suggest that, in certain constrained contexts, the focus should be on the quality of information rather than on the quantity of information generated, and that prototyping should begin as soon as possible during the design process. Ramifications of these findings are discussed in the context of educating future designers on the efficient use of design tools.

Chemisorption on semiconductors: The role of quantum corrections on the space charge regions in multiple dimensions

The chemisorption of O2 on nanoscale n-doped CdS semiconductors is computed in terms of a Wolkenstein isotherm coupled to the Schrodinger Poisson equation. Present numerical results show the dependence of the chemisorbed charge and the differential capacitance on oxygen partial pressure. A comparison against the classical Poisson-Boltzmann approach shows a higher chemisorbed charge in the quantum model, but a greater differential capacitance in the classical case.

Comparison of Information Passing Strategies in System-Level Modeling

Research on complex system optimization has focused on areas including algorithms, coordination strategies, and communication tools. This paper considers optimization from the perspective of information coordination during the solution process. This work aims to determine the potential impact of factors including the role of a system facilitator in managing system-level tradeoffs, the influence of an ideal information scenario, the choice of system variables, and the amount and form of passed information. The goal is not to develop the “best” communication structure or optimization algorithm, but to understand the significance of these factors. A traditional multidisciplinary design optimization coordination framework, a game theoretic approach, and a modified game theory approach are used to mimic design team behaviors. Results suggest these factors can influence the coordination process outcomes: The choice of system variable plays a significant role in the optimality of the final design; perfect inform...

A COMPARISON OF INFORMATION PASSING STRATEGIES IN SYSTEM LEVEL MODELING

Frameworks for modeling the communication and coordination of subsystem stakeholders are valuable for the synthesis of large engineering systems. However, these frameworks can be resource intensive and challenging to implement. This paper compares three frameworks, Multidisciplinary Design Optimization (MDO), traditional Game Theory, and a Modified Game Theoretic approach on the form and flow of information passed between subsystems. This paper considers the impact of “complete” information sharing by determining the effect of merging subsystems. Comparisons are made of convergence time and robustness in a case study of the design of a satellite. Results comparing MDO in two- and three-player scenarios indicate that, when the information passed between subsystems is sufficiently linear, the two scenarios converge in statistically indifferent number of iterations, but additional “complete” information does reduce variability in the number of iterations. The Modified Game Theoretic approach converges to a smaller region of the Pareto set compared to MDO, but does so without a system facilitator. Finally, a traditional Game Theoretic approach converges to a limit cycle rather than a fixed point for the given initial design. There may also be a region of attraction for convergence for a traditional Game Theoretic approach.Copyright

A Comparison of Formal Methods for Evaluating the Language of Preference in Engineering Design

In design, as with many fields, the bases of decisions are generally not formally modeled but only talked or written about. The research problem addressed in this paper revolves around the problem of modeling the direct evaluation of design alternatives and their attributes as they are realized in linguistic communication. The question is what types of linguistic data provide the most reliable linguistic displays of preference and utility. The paper compares two formal methods for assessing a design team’s preferences for alternatives based on the team’s discussion: APPRAISAL and Preferential Probabilities from Transcripts (PPT). Results suggest that the two methods are comparable in their assessment of preferences. This paper also examines the nature of consistency in the way design teams consider the attributes of a design. Findings suggest that assessment of an attribute can change substantially over time.Copyright