Investigating Embodied Interaction in Near-Field Perception-Action Re-Calibration on Performance in Immersive Virtual Environments

Immersive Virtual Environments (IVEs) are becoming more accessible and more widely utilized for training. Previous research has shown that the matching of visual and proprioceptive information is important for calibration. Many state-of-the art Virtual Reality (VR) systems, commonly known as Immersive Virtual Environments (IVE), are created for training users in tasks that require accurate manual dexterity. Unfortunately, these systems can suffer from technical limitations that may force de-coupling of visual and proprioceptive information due to interference, latency, and tracking error. It has also been suggested that closed-loop feedback of travel and locomotion in an IVE can overcome compression of visually perceived depth in medium field distances in the virtual world [33, 47]. Very few experiments have examined the carryover effects of multi-sensory feedback in IVEs during manual dexterous 3D user interaction in overcoming distortions in near-field or interaction space depth perception, and the relative importance of visual and proprioceptive information in calibrating users\u27 distance judgments. In the first part of this work, we examined the recalibration of movements when the visually reached distance is scaled differently than the physically reached distance. We present an empirical evaluation of how visually distorted movements affects users\u27 reach to near field targets in an IVE. In a between subjects design, participants provided manual reaching distance estimates during three sessions; a baseline measure without feedback (open-loop distance estimation), a calibration session with visual and proprioceptive feedback (closed-loop distance estimation), and a post-interaction session without feedback (open-loop distance estimation). Subjects were randomly assigned to one of three visual feedbacks in the closed-loop condition during which they reached to target while holding a tracked stylus: i) Minus condition (-20% gain condition) in which the visual stylus appeared at 80\% of the distance of the physical stylus, ii) Neutral condition (0% or no gain condition) in which the visual stylus was co-located with the physical stylus, and iii) Plus condition (+20% gain condition) in which the visual stylus appeared at 120% of the distance of the physical stylus. In all the conditions, there is evidence of visuo-motor calibration in that users\u27 accuracy in physically reaching to the target locations improved over trials. Scaled visual feedback was shown to calibrate distance judgments within an IVE, with estimates being farthest in the post-interaction session after calibrating to visual information appearing nearer (Minus condition), and nearest after calibrating to visual information appearing further (Plus condition). The same pattern was observed during closed-loop physical reach responses, participants generally tended to physically reach farther in Minus condition and closer in Plus condition to the perceived location of the targets, as compared to Neutral condition in which participants\u27 physical reach was more accurate to the perceived location of the target. We then characterized the properties of human reach motion in the presence or absence of visuo-haptic feedback in real and IVEs within a participant\u27s maximum arm reach. Our goal is to understand how physical reaching actions to the perceived location of targets in the presence or absence of visuo-haptic feedback are different between real and virtual viewing conditions. Typically, participants reach to the perceived location of objects in the 3D environment to perform selection and manipulation actions during 3D interaction in applications such as virtual assembly or rehabilitation. In these tasks, participants typically have distorted perceptual information in the IVE as compared to the real world, in part due to technological limitations such as minimal visual field of view, resolution, latency and jitter. In an empirical evaluation, we asked the following questions; i) how do the perceptual differences between virtual and real world affect our ability to accurately reach to the locations of 3D objects, and ii) how do the motor responses of participants differ between the presence or absence of visual and haptic feedback? We examined factors such as velocity and distance of physical reaching behavior between the real world and IVE, both in the presence or absence of visuo-haptic information. The results suggest that physical reach responses vary systematically between real and virtual environments especially in situations involving presence or absence of visuo-haptic feedback. The implications of our study provide a methodological framework for the analysis of reaching motions for selection and manipulation with novel 3D interaction metaphors and to successfully characterize visuo-haptic versus non-visuo-haptic physical reaches in virtual and real world situations. While research has demonstrated that self-avatars can enhance ones\u27 sense of presence and improve distance perception, the effects of self-avatar fidelity on near field distance estimations has yet to be investigated. Thus, we investigated the effect of visual fidelity of the self-avatar in enhancing the user\u27s depth judgments, reach boundary perception and properties of physical reach motion. Previous research has demonstrated that self-avatar representation of the user enhances the sense of presence [37] and even a static notion of an avatar can improve distance estimation in far distances [59, 48]. In this study, performance with a virtual avatar was also compared to real-world performance. Three levels of fidelity were tested; 1) an immersive self-avatar with realistic limbs, 2) a low-fidelity self-avatar showing only joint locations, and 3) end-effector only. There were four primary hypotheses; First, we hypothesize that just the existence of self-avatar or end-effector position would calibrate users\u27 interaction space depth perception in an IVE. Therefore, participants\u27 distance judgments would be improved after the calibration phase regardless of self-avatars\u27 visual fidelity. Second, the magnitude of the changes from pre-test to post-test would be significantly different based on the visual details of the self-avatar presented to the participants (self-avatar vs low-fidelity self-avatar and end-effector). Third, we predict distance estimation accuracy would be the highest in immersive self-avatar condition and the lowest in end-effector condition. Forth, we predict that the properties of physical reach responses vary systematically between different visual fidelity conditions. The results suggest that reach estimations become more accurate as the visual fidelity of the avatar increases, with accuracy for high fidelity avatars approaching real-world performance as compared to low-fidelity and end-effector conditions. There was also an effect of the phase where the reach estimate became more accurate after receiving feedback in calibration phase. Overall, in all conditions reach estimations became more accurate after receiving feedback during a calibration phase. Lastly, we examined factors such as path length, time to complete the task, average velocity and acceleration of physical reach motion and compared all the IVEs conditions with real-world. The results suggest that physical reach responses vary systematically between the VR viewing conditions and real-world

Using Modified Similarity Multiple criteria Decision Making technique to rank countries in terms of Human Development Index

Purpose:Human Development Index (HDI) reported annually by the United Nations Development Program (UNDP) is apopular measure of human well-being. The purposeof this study is to propose a Multiple Criteria Decision Making (MCDM) technique named Modified Similarity technique for ranking countries based on multi criteria HDI. Design/methodology/approach:In Human Development Reports (HDRs), the HDI for each country isfirst calculated from the average of the health, education and income dimension indices with equally allocatedweight. Then the countries are ranked based on this index. Regarding the criticisms the method ofcalculating the HDI has received, this study usesModified Similarity Multi Criteria Decision Making methodfor ranking countries based on multi criteriaHDI, as an alternative method to the average method, which is being used in annually reported HDRs. Findings: We used the four HD indices mentioned in the 2010 and 2011 HDRs to rank 187 countries which have been investigated in the 2011 HDR. The results of ranking countries by the Modified Similarity technique were somewhat different from the 2011 HDR ranking. Originality/value:Some of the HDI criticisms are related to the method of calculating the index in the form of computing theaverage of the three health, education and income dimension indices with equally allocated weight. in an attempt to eliminatesome of the weaknesses associated with the index, this study uses Similarity technique, as an alternative to the average method of ranking countries in terms of humandevelopment. In addition due to some discrepancies associated with the Similarity technique introduced by Deng (2007), a Modified Similarity technique is discussed.Peer Reviewe

Comparison of educational effectiveness between lecture and demonstration based methods on emergency medical services providers of Mashhad city in dealing with patients suspected of having acute coronary syndrome

Introduction: acute coronary syndrome (ACS) is a common cause of emergency visit. Early administration of aspirin is associated with decreased mortality rate. Thus, aspirin should be administrated immediately to the patient with suspected ACS. Emergency medical services (EMS) providers should be trained to respond to heart emergencies and become familiar with presentations and complications of ACS. In this study, the effect of two educational methods â lecture and demonstration â on EMS providers were compared. ..

Investigating the evolution of gender’s role in work-life discourse: Bibliometric and visualization analysis

For almost three decades, the issue of work-life interface of employees has been considered by researchers in this field. With the wider presence of women in professional activities, the issue of gender and its role in work-life interface is becoming more important and the number of research in this field is increasing. The purpose of this article is to provide a systematic review of research conducted in this field and to examine their evolution. Accordingly, studies in the field of work-life interface with emphasis on the role of gender, from the beginning until now (1991 to 2021) were extracted from the Web of Science database and analyzed using VOS Viewer software. The results were presented in two main sections. First; Descriptive information that included the quantitative trend of research and citations in this field, top articles, most active researchers, countries, journals and universities, and second; visualization analyses also include co citation and keywords co-occurrence which show the intellectual and conceptual structure of this field. The results showed that in addition to the increasing quantitative growth of research on this concept, the evolution of research topics in this discourse was from the negative side of work-life interface of women in the form of work-life conflict to the positive side of this concept in the form of enrichment and work-life balance and finally, the ideological concepts of gender role, gender attitude, gender equality, and gender inequality

Removal of Nitrate Ion from Aqueous Solution using Octa Decyl Amine Modified Montmorillonite Nanoclay

The purpose of this study was to remove nitrate ion using nano clay montmorillonites whose surface was modified using the octa decy lamine functional group. In this study, nano clay was first modified using octa decyl amine and the surface properties of this nanoparticle modified by scanning electron microscopy (SEM) and X-ray diffraction spectrum (XRD) were investigated. In the next step, the nitrate ion adsorption process was investigated by using adsorption model and by examining the parameters of contact time between adsorbent and adsorbent, absorbent concentration, pH effect and effect of adsorbent dose on nitrate removal. Absorption rate was evaluated by atomic absorption. The results showed that the correction of the nanoclay surface by the amine group increased the interlayer spacing from 7.58 Angstrom to 22.91 Angstrom and the size of the modified nanoparticles was about 80 to 100 nanometers. By increasing the nano absorbing surface, the number of sites active absorption has increased. In the study of adsorption of nitrate ions, the maximum adsorption at pH was 5, the initial concentration of 100 mg/l, the contact time of 40 min, and the 0.7 g of nano-adsorbent. In the study of equilibrium isotherms, it was found that the adsorption process follows Langmuir and Freundlich isotherms and the highest single-layer adsorption capacity was 18.352 mg/g. The kinetics of the above process is consistent with the second-order kinetic model and the amount of absorbance per unit mass of the adsorbent in equilibrium is 2.518 mg/g

School girls and childbearing motives: A randomized clinical trial through hidden curriculum

Background: Childbearing motives are considered as the primary stimulus of fertility and the importance of making fertility decisions in humans. Objective: The aim of this study is to determine the effect of a new form of interactional program on the childbearing motives of students. Materials and Methods: According to a well-defined, single-blind randomized controlled trial, we selected eight government schools in Tehran. Students in the age range of 7-12 yr and 16-18 yr (130 students in each school with a total number of 260) were selected for a series of intervention from storytelling to free discussion on a special subject through the concept of hidden curriculum. We evaluate the outcome with pretest-posttest based on the Miller childbearing motives questionnaire. One month after the last intervention, final evaluation took place. Results: The findings showed that after an intervention conducted in the best way, all positive scores were promoted while the negative ones declined. One the other hand, no matter what really the participant’s groups were, their total intention score got better. In this way, the total positive scores were significantly increased in the intervention groups (p = 0.000) Also, the students in high school significantly improved in positive scores and the negative score decreased in them. Conclusion: This study showed that the fundamental childbearing motives even with small interventions can be improved. Our intervention could improve the positive childbearing motives among school girls. In this regard, the role of some confounding factor such as the role of some confounding factors such as religious beliefs in family, maternal education is most important. Key words: Childbearing, Motive, School, Adolescents, Intention

Investigating the Impact of Perturbed Visual and Proprioceptive information in Near-Field Immersive Virtual Environment

We report the results of an empirical evaluation to examine the carryover effects of calibrations to one of three perturbations of visual and proprioceptive feedback: i) Minus condition (-20% gain) in which a visual stylus appeared at 80% of the distance of a physical stylus, ii) Neutral condition (0% gain) in which a visual stylus was co-located with a physical stylus, and iii) Plus condition (+20% gain) in which the visual stylus appeared at 120% of the distance of the physical stylus. Feedback was shown to calibrate distance judgments quickly within an IVE, with estimates being farthest after calibrating to visual information appearing nearer (Minus condition), and nearest after calibrating to visual information appearing further (Plus condition)

Job Crafting and the Role of Self-efficacy and Engagement in the Academic Jobs

Introduction: Job crafting is the process of making proactive changes in the boundariescomposing a job, which are known as mental fences that individuals adopt to define their job’sphysical, emotional, or cognitive limitations. Job crafting considers the change in the natureof jobs, whether realistically in the form of task crafting and relational crafting, or as cognitiveperceptions. In this study, the role of self-efficacy as the antecedent and work engagement asthe consequence of job crafting was studied.Methods: The jobs were academic and the sample was selected from faculty members ofShiraz University of Medical Sciences. The research questionnaires were distributed amongfaculty members of Shiraz University of Medical Sciences. A PLS model is analyzed andinterpreted in two stages: the assessment of the reliability and validity of the measurementmodel, and the assessment of the structural model.Results: The results showed that self-efficacy was positively related to all dimensions ofjob crafting. Moreover, the triple dimensions of job crafting had a significant positiveeffect on work engagement. The moderating role of gender and academic level in therelationship between self-efficacy and work engagement was confirmed. However, theresults showed that gender did not moderate the relationship between self-efficacy andtask crafting.Conclusion: The main novelty of this research is the study of job crafting, self-efficacy andengagement variables considering the moderating role of gender and academic level

Relation between third trimester urinary iodine concentrations and newborn thyrotrophic hormone

Background: The aim of the study was to evaluate the third trimester urinary iodine excretion and to assess its relation with newborns thyroid function. Materials and Methods: A total of 208 healthy third trimester pregnant women without previous history of thyroid disease were included in the study. Urinary iodine levels of mothers were measured and neonatal TSH levels were screened on the 3- 5th day following birth.Results: The median urinary iodine level in the mothers was 50μg/L. According to WHO criteria for iodine status:14.9%, 34.1% and 49.6% had severe, moderate and mild iodine deficiency, respectively, and only 1.4%, had the adequate iodine intake . In 6 neonate (2.8%) who their TSH level were between 5- 10 IU/ml, nobody had criteria for congenital hypothyroidism at recall visit (15th day). Our results showed the reverse relation between mean Neonatal TSH levels and mother’s third trimester iodine level (r= -0.19, p=0.006).Conclusion: Although all of mothers included in this study stated that they were using iodized salt, iodine deficiency was frequent . There was also a significant relation between mean neonatal TSH levels and mother’s third trimester iodine urinary level