Close Distance Research Articles

Redesain Redesain Perumahan Transmigrasi Lokal Suku Asmat dan Mappi di Tepian Sungai Maro Merauke

The Asmat and Mappi tribes are indigenous Papuan tribes that have inhabited the outskirts of the Maro river since the 1970s. These two tribes were accommodated by the Merauke district government at the start of the local transmigration program from the interior to the city of Merauke. The local transmigration housing, which has been inhabited for decades, in fact, has several problems, namely, the lack of fulfillment of settlement-scale housing infrastructure requirements and the very close distance between housing and the outskirts of the Maro river which is a waterfront area. This study aims to analyze the local transmigration housing area of the Asmat and Mappi tribes on the banks of the Maro river and further produce a new design in the form of Redesign.
 This type of research is descriptive qualitative with inductive analysis. Data collection method with direct obseravation, interviews/ interviews, literature studies and documentation on 50 local transmigration houses consisting of 30 Asmat tribal transmigration houses and 20 Mappi tribal transmigration houses located in Kelapa Lima village, Merauke District.
 The results of the analysis recommend a Redesign Result in the form of a Stilt House that is livable and safe from tidal flooding due to the rise of the Maro river water level.

Comparisons of measured and estimated distances and angles from sightings surveys

Photogrammetric systems using video cameras were used to measure radial distances to sightings during the SCANS-II, CODA and SOWER surveys. These surveys included sightings of a variety of species from harbour porpoise, at distances of a few hundred metres, to large baleen whales at distances greater than 10km. A total of 910 initial sightings with estimated distances from reticles and measured distances from video, using 7 × 50 (636) or 25× ‘Big Eye’ (274) binoculars, were compared. Bearings to sightings were also measured from still images. The CVRMSE in distances varied between 0.19 and 0.33 for reticle binoculars. Comparisons of measured distances to simultaneous sightings by other observers using naked eye gave a CVRMSE of 0.39 for naked eye estimates. There was a consistent, non-linear pattern in all data sets, of over-estimating close distances to sightings of surfacing cetaceans and under-estimating those further away. However, this pattern was not evident from the distance experiments on SOWER to fixed targets which also had a much lower variance (CVRMSE = 0.13). Bearing data from SCANS-II and CODA showed around 5% of estimates had gross errors greater than 20º that were attributed to mistakes. For the remaining values, RMS errors were in the range 5.7º–7.2º for SCANS-II and CODA and 4.9º for SOWER. Both distance and angle errors will make a substantial contribution to the variance of abundance estimates and simulated data showed that the observed non-linear nature of distance errors may cause considerable bias even when linear regressions might suggest little bias. There still remain technological challenges in operating complex electronic systems at sea to measure distances and bearings, but investment in these methods should be a cost effective way of reducing bias and improving precision of cetacean abundance estimates.

Proximity and Tactile Sensor Combining Multiple ToF Sensors and a Self‐Capacitance Proximity and Tactile Sensor

Future labor forces are anticipated to include collaborative robots that work alongside humans in the same environment. Proximity and tactile sensors are among the most important devices for collaborative robots to operate safely. In this paper, we propose a proximity and tactile sensor for a collaborative robot that combines multiple time‐of‐flight (ToF) sensors and a self‐capacitating proximity and tactile sensor. ToF sensors can detect the distance to an object and have a long measurement range. However, at close distances, their detection accuracy deteriorates, and blind spots may likely not be detected. Conversely, the self‐capacitance proximity and tactile sensor detect objects within the blind spots of ToF sensors and contact conditions because the sensor can detect an object before and after contact, being highly sensitive in the proximity range. In the proposed sensor, the electrodes of the self‐capacitance are enlarged, and multiple ToF sensors are used to expand the measurement range and reduce blind spots. A prototype sensor was seamlessly able to measure objects from approximately 400 mm to contact conditions. In addition, the robot arm with the prototype sensor could be controlled in real time using the measured data of the sensor. Therefore, we believe that the proposed sensor can be potentially used as a proximity and tactile sensor for collaborative robots. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Nectary development in Cleome violacea.

Nectaries are a promising frontier for plant evo-devo research, and are particularly fascinating given their diversity in form, position, and secretion methods across angiosperms. Emerging model systems permit investigations of the molecular basis for nectary development and nectar secretion across a range of taxa, which addresses fundamental questions about underlying parallelisms and convergence. Herein, we explore nectary development and nectar secretion in the emerging model taxa, Cleome violacea (Cleomaceae), which exhibits a prominent adaxial nectary. First, we characterized nectary anatomy and quantified nectar secretion to establish a foundation for quantitative and functional gene experiments. Next, we leveraged RNA-seq to establish gene expression profiles of nectaries across three key stages of development: pre-anthesis, anthesis, and post-fertilization. We then performed functional studies on five genes that were putatively involved in nectary and nectar formation: CvCRABSCLAW (CvCRC), CvAGAMOUS (CvAG), CvSHATTERPROOF (CvSHP), CvSWEET9, and a highly expressed but uncharacterized transcript. These experiments revealed a high degree of functional convergence to homologues from other core Eudicots, especially Arabidopsis. CvCRC, redundantly with CvAG and CvSHP, are required for nectary initiation. Concordantly, CvSWEET9 is essential for nectar formation and secretion, which indicates that the process is eccrine based in C. violacea. While demonstration of conservation is informative to our understanding of nectary evolution, questions remain. For example, it is unknown which genes are downstream of the developmental initiators CvCRC, CvAG, and CvSHP, or what role the TCP gene family plays in nectary initiation in this family. Further to this, we have initiated a characterization of associations between nectaries, yeast, and bacteria, but more research is required beyond establishing their presence. Cleome violacea is an excellent model for continued research into nectary development because of its conspicuous nectaries, short generation time, and close taxonomic distance to Arabidopsis.

Understanding and improving temporary road sign stability

Temporary road signage is used throughout road networks to regulate traffic and provide warnings to road users. Wind and other factors induce frequent falling of temporary road signage and are a major road safety concern that needs to be addressed. The main aim of this paper was to gain an understanding of temporary road sign stability in the presence of passing road trains and investigate the possibility of stabilising temporary road signage through appropriate design modifications. Simulations and experimental trials were carried out to assess the stability of current temporary road signs used in the industry. This analysis used Ansys Fluent to simulate fluid dynamics in order to infer road sign stability. A field experimental trial was performed in Western Australia’s Pilbara Region using a modified temporary road sign developed based on the outcome of the Ansys simulation. The findings from the simulations showed that the current design is unstable and highly prone to wind induced failure. The simulations suggest that road train transit at 100 km/h is capable of inducing approximately 8 m/s wind velocity in the proximity of the sign, which is greater than that permissible for a rigid sign with no leg mobility. Field trials showed that the modified sign remained stable at 1.2 m from the edge line although it was still prone to falling over at closer distances.

Selecting the Safe Area and Finding Proper Ventilation in the Spread of the COVID-19 Virus

Coughing and sneezing are the main ways of spreading coronavirus-2019 (SARS-CoV-2). People sometimes need to work together at close distances. This study presents the results of the computational fluid dynamics (CFD) simulation of the dispersion and transport of respiratory droplets emitted by an infected person who coughs in an indoor space with an air ventilation system. The resulting information is expected to help in risk assessment and development of mitigation measures to prevent the infection spread. The turbulent flow of air in the indoor space is simulated using the k-ε model. The particle equation of motion included the drag, the Saffman lift, the Brownian force and gravity/buoyancy forces. The innovation of this study includes A: Using the Eulerian–Lagrangian CFD model for the simulation of the cough droplet dispersion. B: Assessing the infection risk by the Wells–Riley equation. C: A safer design for the ventilation system (changing the ventilation supplies and exhausts in the indoor space and choosing the right location for air ventilation). The droplet distribution in the indoor space is strongly influenced by the air ventilation layout. The air-curtain flow pattern significantly reduces the dispersion and spreading of virus-infected cough droplets. When the ventilation air flow occurs along the room length, it takes about 115 s for the cough droplets to leave the space. However, when the ventilation air flow is across the width of the indoor space and there are air curtain-type air flow patterns in the room, it takes about 75 s for the cough droplets to leave the space.

Understanding TMS and knowledge transfer in the social media mobile App context

PurposeKnowledge transfer which refers to the communication of knowledge from a source so that it is learned and applied by a recipient has long been a challenge for knowledge management. The purpose of this study is to understand influencing factors of transactive memory system (TMS) and knowledge transfer.Design/methodology/approachDrawing on the theories of communication visibility, social distance and flow, this study develops a research model. Then, data are collected from users of the social media mobile App. Partial least squares-structural equation modeling (PLS-SEM) is employed to analyze data.FindingsTMS is a valid second-order construct in the social media mobile app context, which is more reflected by credibility. Meanwhile, communication visibility and social distance each have positive effects on TMS which further has a positive effect on knowledge transfer. Flow has a positive effect on knowledge transfer.Practical implicationsDevelopers of the mobile App should carefully consider the role of information and communication technology (ICT) in supporting TMS and knowledge transfer. They should consider recommendation algorithm so that the benefit of communication visibility can be retained. They should design the feature to classify users based on similarity so as to stimulate users' feeling of close social distance. They should keep on improving features based on users' holistic experience.Originality/valueThis study incorporates the perspectives of communication visibility, social distance and flow to understand TMS and knowledge transfer, presenting a new lens for research.

An efficient method for parameter estimation and separation of multi-component LFM signals

In this paper, an efficient and robust algorithm for fast parameter estimation and separation of multi-component LFM signals is proposed, which is suitable for processing overlapping and intersect LFM signals in the time-frequency plane. First, the key innovative idea of the algorithm is to use the fourth-order origin moment of fractional Fourier transform spectrum to formulate a reasonable search strategy for the optimal rotation order to achieve parameter estimation, and propose a step-by-step filtering technique for signals in the fractional Fourier domain achieve the signal separation we are interested in. Then, the proposed algorithm overcomes the problems of low estimation accuracy and large computational of traditional two-dimensional search and time-frequency analysis methods by virtue of good impulse characteristics and anti-noise performance. Different from existing solutions, the method avoid interference problems between multiple signals with close time-frequency distance, overlapping and cross components. Moreover, the error analysis of the linear frequency modulation signal is carried out, and the Cramer-Rao lower bound for the unbiased estimation of the parameters is derived. Finally, the simulation results demonstrate the accuracy and effectiveness of the proposed method in noisy environments by comparing with traditional methods and existing methods.

Soft calls do not modulate aggressiveness in male common cuckoos toward conspecific territorial intruders: A sequential playback study

In many bird species loud broadcast calls serve as aggressive signals with a large effective radius, whereas soft calls may indicate aggression at a closer distance, and are often directed at a nearby conspecific individual. Male common cuckoos (Cuculus canorus) are famous for their simple cu-coo calls, which are long-range broadcast calls, uttered in long sequences during the breeding season. Cuckoos also produce soft calls, including a single gowk (wah), a series of gowks (gowk series), or a harsher single variant, the guo call. To our knowledge, no previous study has attempted to understand the function of cuckoos’ soft calls. We conducted a sequential playback experiment by (i) first attracting male cuckoos with “cu-coo” calls, and then (ii) playing heterospecific control calls or one of several types of cuckoo soft calls. While the “cu-coo” call attracted focal males, neither the soft conspecific calls nor the heterospecific control calls elicited an additional response. Finally, the gowk series calls did not alter cuckoos’ approach to the speaker when played together with “cu-coo” calls. As cuckoos’ soft calls did not increase or decrease aggression, they instead may advertise the cuckoo’s presence and position for a nearby conspecific.

Active Sound Power Attenuation with a Ring of Harmonic Acoustic Pneumatic Sources fOr Destructive Interference (RHAPSODI) and near field in-duct microphones

Much research has been conducted to investigate active noise control of turbofans with loudspeakers as noise cancellation sources. However, the required power consumption, fragility, and weight and volume penalty make them unsuitable for engine nacelle applications. An alternative source technology, developed at Sherbrooke, is a harmonic acoustic pneumatic source (HAPS). They are mounted on a ring to perform multimodal active noise control in duct by destructive interference of primary noise (RHAPSODI). A dedicated MIMO harmonic control strategy based on complex envelopes is required to control the RHAPSODI with in-duct microphones located at a very close distance from it or with external in-duct microphones located 1 meter away from the duct mouth. During a training phase, active radiated power minimization is performed with the external microphones for different modal components of the primary harmonic noise. The optimal HAPS control and the optimal signals from the in-duct microphones are then used to tune the specific MIMO controller with a field compensation matrix close to the in-duct microphone signals. A typical result shows that RHAPSODI using 5 in-duct microphones and 5 HAPS can provide high attenuation of radiated sound power (22 dB-SPL, 1 kHz, primary sound power 130 dB).

Direct Modeling of Thermal-Radiation Reception by Antenna in Close Range

In this work, an interesting near-field propagation problem in the microwave radiometer calibration is addressed, which is the antenna reception of thermal radiation from calibration target. Efforts in simultaneously modeling the target and antenna within the same 2-D full-wave scenario are reported. Specifically, the coated pyramids and horn antennas are considered. Based on the incoherent nature of local thermal sources in the coating layer and the fluctuation-dissipation theorem (FDT), the direct modeling of receiving power and further brightness temperature ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$BT$ </tex-math></inline-formula> ) at the antenna waveguide port can be achieved. The direct modeling is then quantified based on the classic concept of antenna reception in an ideal blackbody chamber. Further, it is shown in the results that mutual coupling affects the antenna reception in a fluctuating manner, and the target structural radiation raises the antenna reception in a very close distance. That means, the thermal reception can be affected by both the antenna and target structures in the near field. Also, the Lambertian radiation properties of the coated pyramidal blackbody are clarified in the direct calculated results. This work reveals the complex scenario of close range <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$BT$ </tex-math></inline-formula> transfer, and opens the possibility of quantitatively modeling it for practical applications with further investigations.

Statistical Analysis of the Probability of Interaction of Globular Clusters with Each Other and with the Galactic Center on the Cosmological Time Scale According to Gaia DR2 Data

This study is aimed at investigating the dynamic evolution of the orbits of stellar globular clusters (GCs). To integrate the orbits backward in time, the authors use models of the time-varying potentials derived from cosmological simulations, which are closest to the potential of the Galaxy. This allows for estimating the probability of close passages (collisions) of GCs with respect to each other and the Galactic center (GalC) in the Galaxy undergoing dynamic changes in the past. To reproduce the dynamics of the Galaxy in time, five potentials selected from the IllustrisTNG-100 large-scale cosmological database, which are similar in their characteristics to the current physical parameters of the Milky Way, are used. With these time-varying potentials, we have reproduced the orbital trajectories of 143 GCs 10 Gyr back in time using our original phi-GPU N-body code. Each GC was treated as a single physical particle with the assigned position and velocity of the cluster center from the Gaia DR2 observations. For each of the potentials, 1000 initial conditions were generated with randomized initial velocities of GCs within the errors of the observational data. In this study, we consider close passages to be passages with a relative distance of less than 100 pc and a relative speed of less than 250 km/s. To select clusters that pass at close distances from the GalC, the following criterion is applied based only on the relative distance: it must be less than 100 pc. Applying the above criteria, the authors obtained statistically significant rates of close passages of GCs with respect to each other and to the GalC. It has been determined that GCs during their evolution have approximately 10 intersecting trajectories with each other on the average and approximately 3 to 4 close passages near the GalC in 1 Gyr at a distance of 50 pc for each of the chosen potentials.

Suppression of particle formation by gas-phase pre-reactions in (100) MOVPE-grown β -Ga2O3 films for vertical device application

This work investigated the metalorganic vapor-phase epitaxy (MOVPE) of (100) β-Ga2O3 films with the aim of meeting the requirements to act as drift layers for high-power electronic devices. A height-adjustable showerhead achieving a close distance to the susceptor (1.5 cm) was demonstrated to be a critical factor in increasing the stability of the Ga wetting layer (or Ga adlayer) on the surface and reducing parasitic particles. A film thickness of up to 3 μm has been achieved while keeping the root mean square below 0.7 nm. Record carrier mobilities of 155 cm2 V−1 s−1 (2.2 μm) and 163 cm2 V−1 s−1 (3 μm) at room temperature were measured for (100) β-Ga2O3 films with carrier concentrations of 5.7 × 1016 and 7.1 × 1016 cm−3, respectively. Analysis of temperature-dependent Hall mobility and carrier concentration data revealed a low background compensating acceptor concentration of 4 × 1015 cm−3.

Pl@ntNet Crops: merging citizen science observations and structured survey data to improve crop recognition for agri-food-environment applications

We present a new application to recognize 218 species of cultivated crops on geo-tagged photos, ‘Pl@ntNet Crops’. The application and underlying algorithms are developed using more than 750k photos voluntarily collected by Pl@ntNet users. The app is then enriched by data and photos coming from the European Union’s (EU) Land Use and Coverage Area frame Survey (LUCAS). During five tri-annual LUCAS campaigns from 2006 to 2018, 242 476 close-up ‘cover’ photos of crops were collected. The survey protocol for these photos specified that ‘the picture should be taken at a close distance, so that the structure of leaves can be clearly seen, as well as flowers or fruits’. This unique labelled data provides an opportunity to further generalize the Pl@ntNet computer vision algorithms to recognize crops and enlarge their geographic representivity across the EU. To include LUCAS cover photos, we semantically match Pl@ntNet species and LUCAS legends, predict the species on LUCAS cover photos with the existing Pl@ntNet algorithm, and consider the accuracy of the classification and the number of species enriched by the photos. By setting a threshold of 0.5 on the Pl@ntNet prediction probabilities, 70 170 LUCAS photos representing 101 species classified with an accuracy of 0.9 were added to the ‘Crops’ app. The thematic accuracy of the legacy LUCAS data was improved by distinguishing 218 species, opposed to the original 36 LUCAS levels. Official and publicly financed LUCAS datastreams can now be improved because of Pl@ntNet citizen science, photo collection, and deep learning model development. Further use of the app and policy-relevant workflows in the agri-food-environment domain are discussed.

Objective quantification of viewing behaviours during printed and electronic tasks in emmetropic and myopic ultra-Orthodox Jewish men.

Ultra-Orthodox Jewish men are known to have a high prevalence of myopia, which may be due to intense near-work from an early age. This study objectively assessed near-viewing behaviours in ultra-Orthodox and non-ultra-Orthodox men in Israel for different tasks. Ultra-Orthodox (n= 30) and non-ultra-Orthodox (n= 38) men aged 18-33 years participated. Autorefraction, visual acuity, height and Harmon distance were measured. An objective range-finding sensor was mounted on their spectacles while they performed four 10-min tasks in a randomised order: (1) reading printed material, (2) writing printed material, (3) passive electronic and (4) active electronic tasks. Near-viewing distance and the number of viewing breaks were calculated for each task. Statistical analyses included Student t-tests and the Mann-Whitney test between groups and repeated measures ANOVA or Friedman between tasks. For all tasks combined, a significantly shorter viewing distance was observed for the ultra-Orthodox group (36.2± 7.0cm) than for the non-ultra-Orthodox group (39.6± 6.7 cm, p< 0.05). Viewing distances for the passive reading and electronic tasks were shorter for the ultra-Orthodox group (36.9± 7.7cm vs. 41.3± 8.1cm, p< 0.03 and 39.0± 10.1 vs. 43.9± 9.3, p< 0.05, respectively). Viewing distances were significantly different between all four tasks, with writing having the closest distance. No correlation was found between working distance and spherical equivalent or Harmon distance. However, a significant correlation was found in the ultra-Orthodox group between working distance and height for each task (p< 0.04, R< 0.42 for all). There was no difference in the number of viewing breaks between the groups. When reading a book and viewing an iPad, ultra-Orthodox men demonstrated a closer objective working distance than non-ultra-Orthodox men. This shorter viewing distance may contribute to the high prevalence and degree of myopia in this population.

Fracture law of different overlying strata in mining of protective seam under close distance coal seam

AbstractTo study the fracture law of different overlying strata during mining of the lower protective seam under a close distance coal seam at a depth of 1000 m, roof bed‐separation and fissure imaging monitoring were carried out in the inlet roadway ahead of the working face of the JI15‐31040 lower protective seam in the Pingdingshan XII coal mine. The results show that with the overlying strata of the lower protective seam being affected by mining, the displacement of the overlying strata in the roof of 0–4 m was relatively large, and the fissure development was very significant. The displacement of the overlying strata in the roof of 4–12 m was relatively small, the fissures in this range were mostly randomly closed fissures, and this area was stable. Bed separation occurred in the roof of 12–16 m, and the bed‐separating fissures were mostly located at the coal–rock junction. During the mining process, the fractal dimension of the roof gradually increased, and the fissure network developed continuously. The changing process of the fractal dimension of the roof can be roughly divided into three typical change areas: less influence area (distance from the working face &gt; 70 m), rapid increase area (15 m &lt; distance from the working face &lt; 70 m), and stable area (distance from the working face &lt; 15 m), and the area within 70 m in front of the working face was the key supporting area. Under the influence of mining, the roof fissures showed an overall change trend of “from zero to some, from short to long, from small to large, and from narrow to wide.” This study can provide a reference for mining of the protective seam in deep coal seams.

Distributed cooperative control with collision avoidance for spacecraft swarm reconfiguration via reinforcement learning

This article investigates an adaptive, distributed, and cooperative control strategy for the problem of spacecraft swarm reconfiguration, which involves assembling the spacecraft at a close distance to one another while avoiding collisions and keeping spacecraft far from an obstacle. The key idea is to transform their opposite indices into equivalent ones by using soft and hard constraints. The proposed control strategy is inspired by the actor–critic framework of reinforcement learning (RL) algorithms: The soft constraint is designed by using a critic neural network (NN) for assembling and avoiding obstacles, while collisions among the spacecraft are prevented based on the hard constraint established in an artificial potential field (APF). By drawing support from this idea of equivalent transformation, the adaptive, distributed, and cooperative controller is devised by using an actor NN of the RL algorithm, an APF, and Backstepping control technology. The action NNs are used to estimate the input signals of the desired control and the undesired effects due to disturbance from the APF, and the expected control performance is then obtained by minimizing the output of the critic NN. The computational burden incurred by the NNs is significantly reduced by reducing the number of parameters that need to be learned by NNs. Lyapunov stability theory is used to guarantee that all signals in this closed-loop system are ultimately uniformly bounded to ensure its stability. The results of simulations of a swarm of spacecraft demonstrated the effectiveness of the proposed control strategy.

Mathematical Model and Dynamics Analysis of the Stingless Bee (Trigona sp.) in A Colony

Trigona sp. is a stingless bee species that is widely distributed in tropical countries. It has castes in thecolony, i.e. queen, worker, and male bee. Despite its size, Trigona sp. can produce high-quality commoditiessuch as honey, propolis, and bee pollen. However, it is a vulnerable species since it’s pretty easy to be predatedby several predators and has a relatively short lifespan. In addition, there are still few mathematical studiesthat discuss the population dynamics of Trigona sp. Thus, in this study, we construct a mathematical modelof the Trigona sp. population in the form of a dynamical system. The model is a nine-dimensional non-lineardifferential equation that is constructed based on the stages in the bee population, namely the stages of eggs,larvae, and adult bees from each colony except the queen colony. Coexistence analysis, stability of equilibria, and also the death parameter sensitivity analysis are carried out in two scenarios. The first scenario is a situation where none of the workers die so that the food supply at the larval stage is sufficient. Meanwhile, the second scenario is a more common situation where some worker bees die from exhaustion resulting in an insufficient food supply for the larvae stage. Stable coexistence of all sub-structures and structural dependence on the foraging behavior of the workers are shown. All the results will be presented in numerical simulation. From the results of the coexistence and stability analysis, bee farmers can maintain food availability by increasing the number of workers in a colony, or providing food sources with high contains nectar and propolis at a relatively close distance to reduce the death of worker bees.

Effect of Dental Distance from Implant and MAR Algorithm on the Detection of Vertical Root Fracture in CBCT Images

Three-dimensional cone-beam computed tomography (CBCT) has an important role in the detection of vertical root fractures (VRFs). The effect of artifact generation by high-density objects like dental implants on image quality was well documented. This study aimed to assess the effect of tooth-implant distance and the application of metal artifact reduction (MAR) algorithm on the detection of VRFs on CBCT scans. This study was conducted on 20 endodontically treated single-rooted teeth. VRFs were induced in 10 teeth, while the other 10 remained intact. The implant was inserted in the right second premolar socket area, and two teeth were inserted in right canine and right first premolar sockets area randomly and underwent CBCT with and without the application of MAR algorithm. SPSS 21 was used to analyze the results (alpha=0.05). According to the findings of this study, all four variables of sensitivity, specificity, accuracy, and positive predictive values in diagnosis were higher in cases without MAR software at both close(roots in first premolar sockets) and far distances (roots in canine sockets) from the implant. However, the highest rate of diagnosis accuracy of the first and second radiologists was in the far distance group from the implant without MAR, and the lowest rate of diagnosis accuracy in the first and second radiologists was in the close distance to the implant. Applying MAR algorithm had no positive effect on detection of VRFs on CBCT scans in both close and distant scenarios.

Keeping distance with a telepresence robot: A pilot study

IntroductionTelepresence robots (TPRs) are the subject of an emerging field of application and research that has recently received attention from various disciplines. Most of the relevant research has been done in computer science, while the interest from psychology and education has been relatively modest. Proximity plays an important role in personal interactions. Although human spatial behavior has been widely studied in social psychology, little attention has been paid to the spatial behavior of humans and TPRs.MethodsThe purpose of this paper is to present the results of a pilot study that investigated a certain aspect of spatial behavior – physical proximity or interpersonal distance – based on four social zones of interpersonal distance that characterize Western culture: intimate, personal, social, and public. The study conducted an experiment involving participants both in person and via TPRs, using the Double 3 TPRs in various simulated situations.ResultsAccording to the findings, when interacting with a TPR, most participants maintained a communication distance of 60 to 160 cm, which is the borderline between personal and social distance, quite similar to normal human-to-human social communication. Status and previous relationship did not play any role in the choice of communication distance, but there were significant gender differences. On average, male participants chose a shorter distance to interact with TPRs compared to female participants. Persons with previous computer gaming experience chose a significantly shorter communication distance compared to persons with no such experience. A little more than half of the participants found the method of communication through TPRs to be pleasant.DiscussionTPR mediated persons might be perceived as “real” when communicating with physically present persons, with similar norms applied as in human-to-human social interactions. Especially in the context of classroom communication, people keep communication distances comparable to far personal or close social distances. These findings suggest that implementation of TPRs in education does not put additional requirements for physical space in classroom.