A Steering Wheel Angle Analysis of Old and Young Drivers in Right Turning at Intersection

Taebeum Ryu,Byung Chan Min 대한인간공학회 2011 大韓人間工學會誌 Vol.30 No.2

Due to the ageing-related degradation in physical and cognitive abilities, the elderly have difficulty in car driving and this is related to the high rate of car accidents among them. This study investigated the kinematic characteristics of old drivers' steering in right turning at intersections by comparing with young drivers. Thirteen old(60~70) and thirteen young(20~30) drivers who participated in the experiment turned their cars right side at intersections in a driving simulator. As results, the completion time of right turning at intersection of old drivers was larger than that of young drivers. The speeds of vehicle at the beginning and ending point of the right turning area of old drivers were smaller than those of young drivers, and also the steering angle at the ending point of the turning area of the former was smaller than that of the latter. The normalized jerk of old driver's steering was significantly larger than that of young drivers. These results indicate that old drivers modify their steering movement repeatedly and take the driving strategy of avoiding risks due to their reduced physical capabilities.

An Affective Engineering Approach to Exploring the Impact of Product Weight on Consumer Satisfaction and Perceived Price in Rubber-based Eraser Products

Taebeum Ryu,Jack Ogutu,Richard Olawoyin 대한산업공학회 2023 Industrial Engineeering & Management Systems Vol.22 No.4

Relationships of Musculoskeletal Disorder Symptoms and Perceived Workload among Hospital Workers

Taebeum Ryu,Joobong Song,Myung Hwan Yun,Ji Hyoun Lim 대한인간공학회 2012 大韓人間工學會誌 Vol.31 No.5

Objective: This study aims to survey the prevalence of musculoskeletal disorders(MSD) among Korean hospital workers and to analyze the relationship of MSD symptoms and workload perceived by workers. Background: Despite of high exposure to the MSD risk factors and high MSD symptom prevalence among health care workers, there were not enough studies of MSD prevalence among the hospital workers. Method: This study designed a survey based on Nordic questionnaire to obtain MSD symptoms and the degree of four perceived workloads: work repetition, urgency, physical exertion and satisfaction. In this survey, 1,846 workers in a hospital participated. The prevalence of MSD was analyzed for each body part, and MSD cases, which were predetermined in this study, were identified. The relationship between the MSD cases and each perceived workload was analyzed using chi-square test. Results: The pain in the shoulder was the most prevalent among the workers as 52%, and the low back(37%) and leg discomfort(36%) followed. The MSD cases, in which degree of pain was more than severe, were also the most prevalent in the shoulder(13%). Female workers had higher rate of MSD cases than the males. Among the four workload variables, the physical exertion was the statistically related to MSD cases for all the body parts. In addition, the others also had significant relation to MSD cases except one or two body parts. Conclusion: This study found that Korean hospital workers had MSD symptoms mainly in the shoulder, low back and legs in order, and the perceived workload surveyed in this study was highly correlated with MSD symptoms. Application: This study provides another evidence that subjective physical exertion perceived by workers is an important factor to explain MSD cases as same as the objective one.

Conditions of Applications, Situations and Functions Applicable to Gesture Interface

Taebeum Ryu,Jaehong Lee,Joobong Song,Myung Hwan Yun 대한인간공학회 2012 大韓人間工學會誌 Vol.31 No.4

Objective: This study developed a hierarchy of conditions of applications(devices), situations and functions which are applicable to gesture interface. Background: Gesture interface is one of the promising interfaces for our natural and intuitive interaction with intelligent machines and environments. Although there were many studies related to developing new gesture-based devices and gesture interfaces, it was little known which applications, situations and functions are applicable to gesture interface. Method: This study searched about 120 papers relevant to designing and applying gesture interfaces and vocabulary to find the gesture applicable conditions of applications, situations and functions. The conditions which were extracted from 16 closely-related papers were rearranged, and a hierarchy of them was developed to evaluate the applicability of applications, situations and functions to gesture interface. Results: This study summarized 10, 10 and 6 conditions of applications, situations and functions, respectively. In addition, the gesture applicable condition hierarchy of applications, situation and functions were developed based on the semantic similarity, ordering and serial or parallel relationship among them. Conclusion: This study collected gesture applicable conditions of application, situation and functions, and a hierarchy of them was developed to evaluate the applicability of gesture interface. Application: The gesture applicable conditions and hierarchy can be used in developing a framework and detailed criteria to evaluate applicability of applications situations and functions. Moreover, it can enable for designers of gesture interface and vocabulary to determine applications, situations and functions which are applicable to gesture interface.

Selection and Classification of Smart TV Functions based on Gesture Interface

( Taebeum Ryu ),( Yohan Park ),( Woojin Park ) 한국감성과학회 2014 춘계학술대회 Vol.2014 No.-

Smart TV is considered as one of the best candidates that gesture interface can be successfully applied to. However, it is still unclear which functions should be controlled by gestures and which gesture is most intuitive for TV functions. This study selected smart TV functions likely to be controlled by gestures based on user preference. Moreover, we classified these functions into ones which can be used by an identical gesture in order to reduce the number of gestures for the commands. The more the number of gesture to be used, the less the usability of gesture interface. A total of 88 functions surveyed from a smart TV were evaluated by 40 users with a card ordering method, and 35 functions users want to use with gesture interface were selected with a criterion of preference score. Then, another 35 users classified these functions based on an identical gestures users want to use by an open card sorting method. The 35 functions classified into ten groups: 6 are related to directional gestures, and 4 to others. Six directional groups including 74% (26 of 35) functions directly mapped to up/down/left/right and scaling movements. Only nine functions were mapped to metaphoric or symbolic gesture. This means that most of smart TV functions can be intuitively controlled by a small number of directional gestures if the functions to be controlled are determined before gesture interaction by multimodal interface such as voice control.

Effects of products' weight and size on consumers' preference and satisfaction: focused on battery

( Taebeum Ryu ) 한국감성과학회 2019 한국감성과학회 국제학술대회(ICES) Vol.2019 No.-

This study analyzed preference and satisfaction according to the weight and size of products in order to understand how the size-weight illusion (SWI) occurs in affect. The perceived weight of an object has long been a topic of interest in the field of experimental psychology. Perceived weight is known to be affected not only by the weight of the object, but also by its size, color, and material. A total of 54 participants took part in the experiment. Ten electronic mobile batteries were prepared by combining two sizes and five weight levels. Participants were asked to rate the perceived weight of the batteries by the modulus method and evaluate the preference and the satisfaction of the weight by using the semantic differential (SD) scale of 11 points. The results showed that SWI occurred in terms of the perceived weight of cookies boxes like previous studies, however, SWI appeared only partially in affect. The preference and satisfaction did not increase after a certain weight, and the limit of weight were different according to the size of batteries. This results can be referred to determine the weight and size of a product for affective design and especially utilized for the package design of electronic mobile batteries.

Effect of object shape on perceived weight

( Taebeum Ryu ) 한국감성과학회 2021 추계학술대회 Vol.2021 No.0

The weight of an object is an important research topic in terms of sensory and perception, and it is known that it has size-weight, color-weight, and material-weight illusion due to the influence of size, color, and material as well as the weight of the object. Although the physical size of an object is measured by volume, the size of an object that we subjectively feel depends on the shape of the object even if it has the same volume. Therefore, the shape of the object determines the size of the object, and the weight of the object may change accordingly. Existing related studies analyzed the effect of weight according to three shapes (tetrahedron, cube, and sphere), but only some shapes showed a difference in weight. Therefore, this study tried to experimentally prove the difference in weight according to the shape that has not yet been clearly identified. To this end, this study produced objects with the same physical size (volume) as in previous studies, but with tetrahedron, cube, and spherical shapes. In addition, the object volume in this study was set to 3 types of 64,000, 125,000, and 216,000 cm3, and the weight of the object was set to be 100, 150, and 200 g for small, medium, and large volumes, respectively, in proportion to the size. 38 college students (21 males, 17 females) participated in this weight test, and the perceived weight of a given object compared to a reference object was evaluated according to the modulus method used for sensory size measurement. As a result of the analysis of the experimental data, it was found that both weight (volume) and shape had a significant effect on the feeling of weight. Naturally, the weight (volume) of an object with a large weight (volume) was statistically significantly greater than that of an object with a small weight. At the same weight (volume), the weight of an object according to shape decreased statistically significantly in the order of a sphere, a cube, and a tetrahedron. In the same volume, subjective size according to shape is small in the order of tetrahedron, cube, and sphere (Kahrimanovic et al., 2010). Therefore, the results of weight perception according to shape in this study showed that subjective size of objects according to shape had an effect on weight. This is explained as a kind of size-weight illusion phenomenon.

Selection and classification of smart TV functions based on gesture interface

Taebeum Ryu,Yohan Park,Woojin Park 대한인간공학회 2014 대한인간공학회 학술대회논문집 Vol.2014 No.5

Effect of object shape on perceived weight

( Taebeum Ryu ) 한국감성과학회 2021 한국감성과학회 국제학술대회(ICES) Vol.2021 No.-

The weight of an object is an important research topic in terms of sensory and perception, and it is known that it has size-weight, color-weight, and material-weight illusion due to the influence of size, color, and material as well as the weight of the object. Although the physical size of an object is measured by volume, the size of an object that we subjectively feel depends on the shape of the object even if it has the same volume. Therefore, the shape of the object determines the size of the object, and the weight of the object may change accordingly. Existing related studies analyzed the effect of weight according to three shapes (tetrahedron, cube, and sphere), but only some shapes showed a difference in weight. Therefore, this study tried to experimentally prove the difference in weight according to the shape that has not yet been clearly identified. To this end, this study produced objects with the same physical size (volume) as in previous studies, but with tetrahedron, cube, and spherical shapes. In addition, the object volume in this study was set to 3 types of 64,000, 125,000, and 216,000 cm3, and the weight of the object was set to be 100, 150, and 200 g for small, medium, and large volumes, respectively, in proportion to the size. 38 college students (21 males, 17 females) participated in this weight test, and the perceived weight of a given object compared to a reference object was evaluated according to the modulus method used for sensory size measurement. As a result of the analysis of the experimental data, it was found that both weight (volume) and shape had a significant effect on the feeling of weight. Naturally, the weight (volume) of an object with a large weight (volume) was statistically significantly greater than that of an object with a small weight. At the same weight (volume), the weight of an object according to shape decreased statistically significantly in the order of a sphere, a cube, and a tetrahedron. In the same volume, subjective size according to shape is small in the order of tetrahedron, cube, and sphere (Kahrimanovic et al., 2010). Therefore, the results of weight perception according to shape in this study showed that subjective size of objects according to shape had an effect on weight. This is explained as a kind of size-weight illusion phenomenon.

Development of representative body models of spinal cord disabilities for agricultural equipments

Taebeum Ryu(류태범),Taegu Kim(김태구),Yunjae Kim(김윤재) 대한인간공학회 2021 대한인간공학회 학술대회논문집 Vol.2021 No.11

Objective: This study was intended to create a representative human body model used in the anthropometric design of agricultural tools for people with spinal cord disabilities. Background: Korea’s agriculture is facing a manpower shortage due to a decrease in the population and an aging workforce. Involving disabled people in agriculture as a solution to the problem of manpower shortage in agriculture can help both agricultural workers and people with disabilities, and for this purpose, it is necessary to develop agricultural tools that disabled people can use in agricultural activities. Method: For this purpose, this study used the existing anthropometric data for the spinal cord disabled, and created a representative human body model using the method of boundary for the acceptance range of the distribution of human body size. Results: As a result of factor analysis analysis and human size selection method, 26 anatomical dimensions were reduced to 4 factors, and the human body model group had 16 poles in each dimension to have an acceptance rate of 90% of the human size distribution. made up of models. As a result of the evaluation of the acceptance rate of the representative human model group, only 42% of cases satisfying all 26 human body size ranges in the human body model group, but 88% of cases satisfying all 23 human body size ranges. was close to the rate. Conclusion: The representative human model group for spinal cord disorders was visualized using the Technomatix human model module. Application: This can be utilized in identification of problems with existing agricultural tools and anthropometric design of agricultural tools for the disabled.