• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.401-410
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• 2015

Objective: The present study was to improve the graphic user interface (GUI) of a military computer-based training (CBT) system in terms of usability. Background: Existing studies have focused on usability evaluation of a particular GUI type such as sequence, hierarchy, or context type; however, few research has been conducted which identifies preferred GUI features based on a comparative analysis of different GUI types. Method: A comparative evaluation was conducted by 9 CBT design experts using a 7-point scale (1: very low, 4: neutral, and 7: very high) on hierarchy and context GUI types of a military CBT system in terms of 10 usability criteria. Then, preferred features of the hierarchy and context types being accommodated, a new GUI was developed and validated by 22 CBT users. Results: While the hierarchy type was found preferred by 1.6 times in terms of controllability to the context type, the opposite was found in terms of attractiveness, simplicity, and responsiveness by 0.6, 0.8, and 0.8 times, respectively. The proposed GUI was found superior to the hierarchy and context types in terms of accessibility and informativeness by more than 1.5 times, but inferior to the hierarchy and context type in terms of simplicity by 0.6 and 0.9 times, respectively. Conclusion: The new GUI developed by accommodating the preferred features of the hierarchy and context types improves usability in terms of accessibility and informativeness except simplicity. Application: The comparative analysis of various GUIs can be applied to develop an improved GUI in a systematic manner based on preferred features of the existing GUIs.

• Physical Therapy Rehabilitation Science
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• v.13 no.2
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• pp.187-195
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• 2024

Objective: Physical activity can promote physical and mental well-being. University students are more sedentary recently due to the increased use of computers and other technology. The aim of this study was to investigate differences between immersive 360-degree virtual cycling (IVC) and virtual cycling with head-mounted display (VCHMD) on aerobic capacity and usability in young adults. Design: A crossover study. Methods: Twenty-five university students (13 male, 12 female) participated in this study and completed 2 separate 30 min cycling sessions, such as IVC and VCHMD. In the IVC, participants rode on a stationary cycle while watching curved TV where recorded video was played. To enhance the sense of realism, auditory stimulation was given to the headset, and the gyroscope sensor was used to track the screen as the head moved. In the VCHMD, participants rode on the stationary cycle with head-mounted display, and other conditions were the same as IVC. Participants were assessed the aerobic capacity which included gas analyzer and portable near-infrared spectroscopy, and usability which included simulator sickness questionnaire and system usability scale. Results: Aerobic capacity was significantly difference in the IVC compared with the VCHMD except for the total hemoglobin of right and left rectus femoris and muslce oxygen saturation of left rectus femoris (p<0.05). Cybersickness was less in the IVC than VCHMD and usability was high in the IVC than VCHMD (p<0.05). Conclusions: The findings suggested that IVC might be beneficial exericse to improve aerobic capacity and has lower cybersickness and higher usability than VCHMD.

• Journal of Korean Physical Therapy Science
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• v.31 no.1
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• pp.16-32
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• 2024

Background: Exercise equipments and assistive devices for the disabled are being developed, but improvements for usability are still needed. The purpose of this study was to improve and utilize the developed exercise equipment and assistance devices by conducting usability test for people with spinal cord injury. Design: Cross-sectional Study. Methods: Scenarios and usability indicators were derived by conducting a preliminary usability test, 5 non-disabled men and women aged 19 or older. In the scenario, a total of 9 tasks were sequentially performed, including 2 tasks of entry and exit, 5 tasks of assistance devices and weight stack adjustment, and 2 tasks of pre exercise and exercise. The usability indicators were task success (success or fail), execution time (sec), safety, and convenience. For safety, 7 questions (Likert scale, 1~5 point) related to safety, stability and hazard were derived, and for convenience, the system usability scale (SUS score) was used (range: 0~100, 50 percentile rank is 68 point). Results: As a result of the usability test of people with spinal cord injury, there was a large variation among subjects in the task of adjusting the position of the pulley and support in the execution time (11.64~25.44 seconds), and one person failed to adjust the pulley. The safety level showed a lower score (score = 3 points) than other items in the item of entrapment or skin pressure, and in the case of SUS, the average score was 64.5 points, which was close to the acceptable level. Conclusion: Through the usability test, it was confirmed that exercise equipment for the disabled needs improvement in operability, pinching, and pressure, and that it is necessary to develop an assistive device that provides unrestrained posture information (biofeedback) to maintain correct posture during exercise.

• Journal of Industrial Convergence
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• v.20 no.5
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• pp.77-82
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• 2022

Evaluating methods for software asset have been made based on subjective evaluation criteria. In this study, we try to evaluate the usability of complex assets obtained from the previous measurement of the complexity of the asset management system. The evaluation used a scale provided by measuring logical complexity to measure the complexity of the asset, and evaluated the relationship with the usability of the software asset by measuring the index related to reusability. Therefore, it can be seen that HVs maintain a constant ratio according to the composition of various assets for the two types of assets and maintain the applied consistency. Therefore, it can be determined that an asset optimized in terms of usability can be applied consistently in the architectural design process while securing as much diversity as possible.

• PNF and Movement
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• v.21 no.1
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• pp.129-137
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• 2023

Purpose: The physical therapy diagnosis process requires high-level background knowledge, the ability to obtain added information from patients, accurate examination skills, and a framework for transforming thoughts into a diagnostic decision. Thus, the physical therapy diagnostic process is highly complicated and difficult work. To function as autonomous professionals, physical therapists must develop effective clinical diagnosis skills. As such, mobile application aids can help with accurate and scientific diagnoses. Therefore, this study aims to develop and evaluate the usability of a mobile application for physical therapy diagnoses. Methods: In this study, a diagnostic application was developed using App Inventor, the development environment was the Chrome web browser for Windows 10, and the mobile application was run on a Google Pixel 5. The developed application was evaluated for usability by 20 physical therapists with more than 5 years of clinical experience in the musculoskeletal physical therapy field, and a usability evaluation was conducted using a 5-point Likert scale for accuracy, convenience, satisfaction, and usability. The collected Likert scores were converted into percentages and analyzed as descriptive statistics. Results: The graphical user interface consisted of an initial screen with program guidance, 18 screens presenting the algorithm, and 12 screens presenting the estimated diagnosis based on the algorithm. As such, the usability evaluation of the developed application was as follows: accuracy 100%, convenience 90%, satisfaction 91%, and usability 88%. Conclusion: The newly developed mobile application for physical therapeutic diagnoses has a high accuracy, and it will aid in building an easy and reliable physical therapy diagnosis system.

• Journal of Biomedical Engineering Research
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• v.44 no.6
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• pp.363-376
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• 2023

According to the COVID-19, development of various medical software based on IoT(Internet of Things) was accelerated. Especially, interest in a central software system that can remotely monitor and control ventilators is increasing to solve problems related to the continuous increase in severe COVID-19 patients. Since medical device software is closely related to human life, this study aims to develop central monitoring system that can remotely monitor and control multiple ventilators in compliance with medical device software development standards and to verify performance of system. In addition, to ensure the safety and reliability of this central monitoring system, this study also specifies risk management requirements that can identify hazardous situations and evaluate potential hazards and confirms the implementation of cybersecurity to protect against potential cyber threats, which can have serious consequences for patient safety. As a result, we obtained medical device software manufacturing certificates from MFDS(Ministry of Food and Drug Safety) through technical documents about performance verification, risk management and cybersecurity application.The purpose of this study is to conduct a usability assessment to ensure that ergonomic design has been applied so that the ventilator central monitoring system can improve user satisfaction, efficiency, and safety. The rapid spread of COVID-19, which began in 2019, caused significant damage global medical system. In this situation, the need for a system to monitor multiple patients with ventilators was highlighted as a solution for various problems. Since medical device software is closely related to human life, ensuring their safety and satisfaction is important before their actual deployment in the field. In this study, a total of 21 participants consisting of respiratory staffs conducted usability test according to the use scenarios in the simulated use environment. Nine use scenarios were conducted to derive an average task success rate and opinions on user interface were collected through five-point Likert scale satisfaction evaluation and questionnaire. Participants conducted a total of nine use scenario tasks with an average success rate of 93% and five-point Likert scale satisfaction survey showed a high satisfaction result of 4.7 points on average. Users evaluated that the device would be useful for effectively managing multiple patients with ventilators. However, improvements are required for interfaces associated with task that do not exceed the threshold for task success rate. In addition, even medical devices with sufficient safety and efficiency cannot guarantee absolute safety, so it is suggested to continuously evaluate user feedback even after introducing them to the actual site.

• International Journal of Knowledge Content Development & Technology
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• v.11 no.3
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• pp.63-79
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• 2021

The KJC and KCI services operated by the National Research Foundation of Korea (NRF) need to refer to the global citation index database to set the service direction that researchers want and develop new functions. Therefore, in this study, the usability of Korea's KJC and KCI web databases was evaluated. In addition, FGI verification was performed for a group of experts on KJC and KCI improvement measures derived by academic information experts. The evaluation committee consisted of the researcher group, the society related group, the publisher (academic information distribution organization) group, and the policy-making organization group. A total of 16 experts performed usability evaluation and service improvement proposals for KJC and KCI services. As a result of usability evaluation of KJC and KCI web database using SUS measurement tool, KJC service was evaluated as 73.44, and KCI service was evaluated as good as 64.38. KJC improvement proposals were evaluated positively with 4 points or more for all improvement items, and KCI improvement proposals were positively evaluated with 3.5 points or more for all improvement items. Overall, KJC and KCI error improvements were evaluated with a score of 4 or more, showing strong affirmations. In the future, it is hoped that the improvement proposals and improvements proposed in this study will be applied to the development of KJC and KCI services, so that more quality services will be used by domestic researchers.

• Journal of Practical Engineering Education
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• v.14 no.2
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• pp.367-376
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• 2022

In this study, the user experience was analyzed from the learner's point of view, focusing on the metaverse platform 'Spatial'. SUS(System Usability Scale) was used to evaluate the usability of the metaverse platform 'Spatial' in a college class, and the Magnitude estimation technique was used to evaluate the immersion and satisfaction with the class. In addition, a questionnaire survey was used to collect user experience opinions on the use of 'Spatial' as a teaching tool. Looking at the usability evaluation results of the 'Spatial' system, the students evaluated the usability, immersion, and satisfaction quite positively. Looking at the user experience of metaverse platform 'Spatial', it was found that students highly valued Metaverse as an educational tool that can provide a place for many people to gather and communicate even in a non-face-to-face space. Compared to other online platforms, metaverse has advantages in ease of use, interaction, immersion, and interest. In particular, in addition to keyboard, touch, and display, interaction using the five senses such as voice, motion, and gaze was recognized as a great advantage. On the other hand, it was found that high openness, freedom, and interest factors can both promote learning and inhibit learning. Nevertheless, it is judged that the metaverse platform 'Spatial' can be effectively applied in college classes because it enables various interactions between instructor and learner or between learner and learner.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.571-577
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• 2019

This study examined the usability of express buses for wheelchair users to identify the effectiveness, efficiency and satisfaction of wheelchair boarding systems. The usability of 11 manual wheelchair users and nine powered wheelchair users was evaluated using the following three scenarios: boarding the wheelchair accessible bus, moving inside, and alighting the bus. The results showed that 20 wheelchair users completed three scenarios, which was distributed between 0.33 and 1.36 in the difficulty rating scale of the efficiency. The task effort of the efficiency was measured from 8.36 to 11.78. The acceptability of the satisfaction was distributed between 1.00 and 2.00, and the system usability scale was measured in an acceptable boundary of the C grade at 70.7 points with manual wheelchair users and a B grade at 73.1 points with powered wheelchair users. This study has academic significance because it provides basic evidence for accessibility, securing the right to movement and research methods of public transportation for people with disabilities. To improve the quality level of usability in the future, more study with a larger number of research participants and various wheelchair types should be studied.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.4
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• pp.42-49
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• 2018

Pilot Aptitude Research Equipment (PARE) is a simulator developed to measure or research pilot aptitude and train for student pilots. Design of an ergonomic PARE operation console is required to operate the equipment effectively. This study carried out five steps : (S1) operator questionnaire survey, (S2) anthropometric design formula development, (S3) usability evaluation, (S4) improvement design, and (S5) validation considering both Physical User Interface (PUI) and Graphic User Interface (GUI) of PARE operation console. The operator questionnaire surveyed needs for each PUI and GUI part of the console from two PARE actual operators. In terms of PUI, the anthropometric design formula was developed by using design variables, body dimensions, target population characteristics, and reference posture related to the PARE console. In terms of GUI, the usability evaluation was conducted by three usability testing experts with a 7-point scale (1 : very low, 4 : neutral, 7 : very high) on GUI of the PARE operation console by seven usability criteria. The improved PARE operation console was designed to reflect the optimal values of design variables calculated from design formula, the results from usability testing, and the operator's needs. The improvement effect was observed by 20 people who had experience with the PARE operation console. As a result of the validation, monitor visibility and cockpit visibility for the improved PUI design and visibility and efficiency for the improved GUI design were significantly increased by more than 90% respectively. The improved design of the PARE operation console in this study can contribute to enhance operation performance of the PARE.