사용자경험연구실

As the functional characteristics of passenger vehicles reach satisfactory levels, customers’ concerns with the ergonomic and aesthetic aspects of the interior design have increased. The present study developed satisfaction models of automotive interior materials for six parts including crash pad, steering wheel, transmission gearshift knob, audio panel, metal grain inlay, and wood grain inlay. Based on literature survey, customer reviews on the web, and expert opinions, 8–15 material design variables were defined for the interior parts. The material design characteristics of 30 vehicle interiors were measured and customer satisfaction with the vehicle interiors was evaluated by 30 participants in the 20–30-year-old range. The material design variables were screened by evaluating their statistical, technical, and practical significance and satisfaction models were developed by quantification I analysis. The satisfaction models were used to identify relatively important design variables and preferred design features for the interior parts.

Most regression models of anthropometric variables use stature and/or weight as regressors; however, these ‘flat’ regression models can produce large errors in estimation for anthropometric variables having low correlations with the regressors. A novel method was proposed which estimates anthropometric variables in a hierarchical manner based on the geometric and statistical relationships between the variables. This hierarchical estimation method first constructs estimation structures by analyzing the dimensional characteristics and geometric relationships of the anthropometric variables and then develops regression models based on the estimation structures. The hierarchical estimation method was applied to 60 anthropometric variables (selected for the design of an occupant package layout in a passenger car) by using the 1988 US Army anthropometric survey data. The hierarchical regression models showed a 55% increase in adjusted R2 and a 31% decrease in SE on average when compared with corresponding flat regression models.

The sound of a door opening on a vehicle has a main influence on psychological comfort and affective satisfaction for the vehicle. This study aims to evaluate the auditory pleasantness of the door opening sound and to derive the sound parameters, which can optimize that pleasantness. Fourteen different door opening sounds were selected and recorded. Participants evaluated each recorded door opening sound with the designed questionnaire. Three main results were obtained. First, the questionnaire was developed to evaluate the auditory pleasantness of door opening sound based on five affective attributes: ‘loud’, ‘sharp’, ‘rough’, ‘clear’, and ‘satisfy’. These were selected through previous literature review and expert interviews. Second, ‘Loudness’, ‘sharpness’, ‘roughness’, ‘fluctuation strength’, and ‘tonality’ were selected as the psychoacoustic parameters. These parameters were found to be the important dimensions for the perception of door opening sound. Each affective attribute was related to psychoacoustic parameters by correlation analysis. Finally, the authors developed a model to predict subjective response to the door opening sound through regression analysis. In the incidence of ‘loud’, ‘sharp’, and ‘rough’, high R2 values were shown. Multiple regression was used to create a model to predict auditory pleasantness. The psychoacoustic parameter ‘loudness’ was shown to have a major effect on auditory pleasantness. The parameters ‘loudness’, ‘sharpness’, and ‘roughness’ were shown to affect the attributes of the door opening sound. The result of this study was an optimal model, created through psychoacoustic parameters, to predict the auditory pleasantness of door opening sounds.

Does preferred hand show better performance than non-preferred hand in smart phone text entry using one hand. Is the performance of subjects who use left-preferred hand in smart phone text entry worse than that of others who use right preferred hand among the right handed. This study tried to address these two questions. Thirty young male undergraduate students typed a text using a smart phone which has a touch-based QWERTY keyboard two times with both hands, right and left hand, respectively. The completion time, errors were measured in the text entry tasks. All of participants were right handed, but half of them preferred right hand if they have to use one hand in smart phone text entry and other half preferred left hand. The percentage that preferred hand has better performance than non-preferred hand in smart phone text entry using one hand is less than 90% for right-preferred hand and less than 70% for left-preferred hand. The performance of left hand preferred students is not worse than that of the right hand preferred in one hand text entry of smart phone.

Objective: This study presents an observation and analysis on behavioral characteristics of old users in comparison to young users in the use of control on display interface. Background: Touch interface which allows users to control directly on display, is conceived as delight and easy way of human-computer interaction. Due to the advantage in stimulus-response ensemble, the old users, who typically experiencing difficulties in interacting with computer, would expected to have better experience in using computing machines. Method: Twenty nine participants who are over 50 years old and 14 participants who are in 20s years old were participated in this study. Three primary tasks in touch interface, which are tap, move, and flick, were delivered by the users. For the tap task, response time and point of touch response were collected and the response bias was calculated for each trial. For the move task, delivery time and the distance of finger movements were recorded for each trial. For the flick task, task completion time and flicking distance were recorded. Results: From the collected behavioral data, temporal and spatial differences between young and old users behavior were analyzed. The older users showed difficulty in completing move task requiring eye-hand coordination.

This study attempted to investigate consumers’ preference and satisfaction according to the weight and size of products. Fifty-four students in their twenties who have proved their magnitude estimation ability participated in the affective evaluation experiment on the various weights and sizes of cookie products. The cookie products, for which heaviness is considered positive, used in this experiment were well known to be sold in three types of paper boxes in sizes. In this experiment, nine kinds of cookie boxes were prepared by combining three sizes and three weight levels of the product. The participants evaluated the perceived heaviness of each cookie box by the modulus method and evaluated the preference and satisfaction of the weight with the semantic differential scale. As a result of the study, among the boxes with the same weight, ones of small size were perceived significantly heavy and among the boxes with the same size, ones of heavy weight were perceived significantly heavy. This result means that the size-weight illusion of the object heaviness was also found in this study. Meanwhile, this study found that preference and satisfaction did not increase more than a certain weight. That is, there was a limit to the satisfied and preferred weight for one size of cookie box.