Stereoscopic displays have a promising future because of recent advancements and popularity of handheld devices and maturing head mounted displays. Gesture interaction such as pointing, selection, pinching, and manipulation are now possible in the current virtual environments, where accurate distance judgment is required. In this paper, we address the perception of exocentric distance in stereoscopic displays under two target orientations: horizontal and vertical. Three parallax conditions (on screen, 5 cm from screen, and 10 cm from screen) were considered, where the screen was fixed at a distance of 100 cm from the observer. Four levels of center‐to‐center distance between 10 and 50 cm were employed. The perceptual matching task revealed underestimation in all conditions. The overall judgment of exocentric distance was only about 80% of the actual. We also found a main effect of distance and interaction between layout and distance to be significant. The two important findings of this study are that underestimation of exocentric distance increases as the separation between virtual targets increases and that in vertical orientation, accuracy increases with closer targets. However, the main effects of layout and parallax on accuracy of judgment were not significant. Engineering implications of the results are also discussed in this paper.

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This preliminary study was conducted to provide a literature review about applications of theory of planned behavior and health belief model. These theories have been widely used to explain and predict a person's health-related intention and behavior. Health belief model as well as theory of planned behavior remain the best known theories in health behavior research. The health belief model suggests people's belief about health problems in order to reduce or prevent the chance of disease whereas the theory of planned behavior is about predicting a person's intention or behavior. In this study, we systematically selected and reviewed articles related to the application of theory of planned behavior and health belief model, particularly to its implementation in observing public health behavior. The aim was to identify the implications of theory of planned behavior and health belief model in behavioral health-related research and identify a potential research gap by using these two theories. Our analysis revealed that in Indonesia there were less studies which integrated extension of theory of planned behavior and health belief model, especially in evaluating factors affecting the public behavior from prevention of COVID-19. This study could be a basis of further studies which integrate extended theory of planned behavior and health belief model in investigating public behavior during the pandemic of COVID-19 in Indonesia.

The COVID-19 virus has infected many people, resulting in death tolls around the world. So, it is necessary to adopt a clean and healthy lifestyle and implement health protocols such as using masks, washing hands and maintaining distance. This community service activity aims to provide education and assistance to community representatives in Desa Bojongsoang, Bandung, to always implement a healthy and clean lifestyle and health protocols. Educational activities are carried out by providing counseling with the methods of lectures, discussions, and questions and answers. Material delivery is also conveyed through the media of posters, so that the posters can be affi xed to strategic areas so that it can be seen and read eff ectively. In this activity, an evaluation of the level of community compliance in implementing health protocols while outside the home was also carried out, by distributing questionnaires before the activity took place. As a result, in general the community is disciplined in applying health protocols while outside the home. Several fi ndings were also obtained in this simple survey, so that these fi ndings can be used as initial data/information for local stakeholders to streamline education and socialization in eff orts to prevent the massif transmission of the COVID-19 virus.

Recent developments in virtual environment applications allow users to interact with three-dimensional (3D) objects in virtual environments. As interaction with 3D objects in virtual environments becomes more established, it is important to investigate user performance with such interaction techniques within a specific task. This study investigated two interaction modes, direct and indirect, depending on how the users interacted with the 3D objects, by measuring the accuracy of egocentric distance estimation in a stereoscopic environment. Fourteen participants were recruited to perform an acquisition task with both direct pointing and indirect cursor techniques at three egocentric distances and three task difficulty levels. The accuracy of the egocentric distance estimation, throughput, and task completion time were analyzed for each interaction technique. The indirect cursor technique was found to be more accurate than the direct pointing one. On the other hand, a higher throughput was observed with the direct pointing technique than with the indirect cursor technique. However, there were no significant differences in task completion time between the two interaction techniques. The results also showed accuracy to be higher at the greatest distance (150 cm from the participant) than at the closer distances of 90 cm and 120 cm. Furthermore, the difficulty of the task also significantly affected the accuracy, with accuracy lower in the highest difficulty condition than in the medium and low difficulty conditions. The findings of this study contribute to the understanding of user-interaction techniques in a stereoscopic environment. Furthermore, developers of virtual environments may refer to these findings in designing effective user interactions, especially those in which performance relies on accuracy.

This experiment investigated the accuracy of distance judgment and perception of the frontal extent in a stereoscopic environment. Eight virtual targets were projected in a circular arrangement with two center-to-center target distances (18 cm and 36 cm) and three target sizes (0.6 cm, 1.5 cm, and 3.7 cm). Fourteen participants judged the positions of virtual targets presented at a distance of 90 cm from them by employing two different interaction techniques: the direct selection technique and the virtual cursor technique. The results showed overall higher accuracy with the virtual cursor technique than with the direct selection technique. It was also found that the target size significantly affected the frontal extent accuracy. In addition, significant interactions between technique and center-to-center target distance were observed. The direct selection technique was more accurate at the 18 cm center-to-center target distance along the horizontal (x) and vertical (y) axes, while the virtual cursor technique was more accurate for the 36 cm center-to-center target distance along the y axis. During the direct selection, estimations tended to converge to the center of the virtual space; however, this convergence was not observed in the virtual cursor condition. The accuracy of pointing estimations suffered on the left side of participants. These findings could provide direction for virtual reality developers in selecting proper interaction techniques and appropriately positioning virtual targets in stereoscopic environments.

Production process sustainability refers to a manufacturing system in which manufacturing industries produce products in a sustainable way. In recent years, sustainability has become a major concern and challenge for manufacturing systems because of growing consciousness of the effects of their activities on the environment, society, and economy. Different organizational reports and the academic literature have proposed indicators of sustainable manufacturing that help to measure product and process sustainability. However, little of the previous research is related to employee-activity based indicators for production process sustainability. To bridge the gap, this study identified a set of indicators of production process sustainability based on direct and indirect impacts of manufacturing activities on employees, who are key resources in the entire production process, for efficiently applying a sustainability perspective. In addition, the paper provides an evaluation model for selecting relatively important indicators based on expert opinions. A fuzzy Delphi method was applied for the screening process of the decision makers (experts). A Delphi questionnaire prepared with a nine-point linguistic scale corresponding to respective linguistic variables was utilized to assess expert opinions on the importance of each indicator. These expert opinions were aggregated for each indicator by using an adopted algorithm that considers the degree of importance allocated to the decision makers, and the similarity and distance among decision maker opinions. Lastly, the key employee-activity based indicators were chosen based on the threshold value set.

The COVID-19 pandemic push the learning revolution. The previous onsite learning is suddenly change to online learning. Current technological developments support the online learning application through the use of Learning Management System Platform. However, some problems are found during the application of online learning. Thus, this research aims to improve online learning through the use of Learning Management System Platform. The Technology Acceptance Model and the Technology Readiness Index model were combined to identify the critical factors influencing the intention to use Learning Management System. Fourteen hypotheses were proposed and tested using the Structural Equation Modelling method run in Partial Least Square software. The results indicated that eight hypotheses were accepted. The accepted hypothesis represents the criticality to consider innovativeness, job relevance, perceived enjoyment, perceived security and subjective norm in the Learning Management System usage during online learning during the COVID-19 Pandemic