Analyzing the Impact of Objects in an Image on Location Estimation Accuracy in Visual Localization.

Visual localization refers to the process of determining an observer's pose by analyzing the spatial relationships between a query image and a pre-existing set of images. In this procedure, matched visual features between images are identified and utilized for pose estimation; consequently, the accuracy of the estimation heavily relies on the precision of feature matching. Incorrect feature matchings, such as those between different objects and/or different points within an object in an image, should thus be avoided. In this paper, our initial evaluation focused on gauging the reliability of each object class within image datasets concerning pose estimation accuracy. This assessment revealed the building class to be reliable, while humans exhibited unreliability across diverse locations. The subsequent study delved deeper into the degradation of pose estimation accuracy by artificially increasing the proportion of the unreliable object-humans. The findings revealed a noteworthy decline started when the average proportion of the humans in the images exceeded 20%. We discuss the results and implications for dataset construction for visual localization.

Promoting sustainable packaging applications in the circular economy by exploring and advancing molded pulp materials for food products: a review.

Packaging ensures the safe handling and distribution of fresh and processed food products via diverse supply chains, and has become an indispensable component of the food industry. However, the rapidly expanding use of plastics, especially single-use plastics, as packaging material leads to inadequate waste management, littering, and consequently serious environmental damage, which predominantly affects marine and freshwater sources. Thus, the use of plastics for packaging purposes has become a major public concern and hence a concern among global policymakers. Notably, 26% of the total volume of global plastic production is primarily used for packaging, of which single-use plastics account for 50%, resulting in pollution that may last hundreds of years. This review provides an overview of the manner in which molded pulp products can be utilized to improve sustainability of food packaging applications, by highlighting the manufacturing processes, signifying characteristics features of recyclable molded pulp, and coupling circularity with eco-friendly and safe food product packaging. In this regard, current concepts advocate the implementation of a dynamic and sustainable approach using molded pulp products. This approach encompasses the design and production of eco-friendly packaging, distribution and consumption of packaged products, and collection and recycling of used packaging for subsequent reuse.

Application of patch stimulator for intraoperative neuromonitoring during thyroid surgery: maximizing surgeon's convenience.

BACKGROUND: Intraoperative neuromonitoring (IONM) is frequently used in thyroid surgery to reduce recurrent laryngeal nerve (RLN) injury by providing the surgeon with real-time feedback on nerve stimulation during dissection. We applied a disposable adhesive patch electrode to a dissecting instrument to transfer electrical stimulation to the dissecting instrument for IONM during thyroid surgery. This study aimed to evaluate the feasibility of using the patch stimulator approach for IONM during thyroid surgery. METHODS: We reviewed the medical records of patients who underwent thyroidectomy using both conventional stimulator and adhesive patch stimulator for IONM. The electromyography (EMG) amplitudes of the vagal and the RLNs before (V1, R1) and after thyroid resection (V2, R2) were alternatively checked with each type of stimulator at the same location of each nerve. RESULTS: Fifteen consecutive patients (4 males, 11 females) were included in this analysis, and a total of 38 nerves (19 vagus nerves and 19 RLNs) were evaluated. No statistically significant differences were seen in the mean amplitudes evoked by the patch stimulator and the conventional probe stimulator for the V1 signal (825.5±394.6 vs. 821.8±360.9 µV, P=0.954), R1 signal (1,044.8±471.2 vs. 1,039.2±507.4 µV, P=0.898), R2 signal (1,037.8±495.0 vs. 938.2±415.8 µV, P=0.948), or V2 signal (812.5±391.9 vs. 787.3±355.7 µV, P=0.975). CONCLUSIONS: The patch stimulator was safely and effectively used for IONM during thyroid surgery and provided similar nerve monitoring responses as the conventional stimulator. This approach may be used to enhance the surgeon's convenience during thyroid surgery.

Exogenous Melatonin Reduces Lignification and Retains Quality of Green Asparagus (Asparagus officinalis L.).

Asparagus (Asparagus officinalis L.) is highly perishable because of its high respiration rate, which continues after harvesting and leads to weight loss, increased hardness, color change, and limited shelf life. Melatonin is an indoleamine that plays an important role in abiotic stress. This study was designed to investigate the effects of melatonin on the quality attributes of green asparagus during cold storage. Green asparagus was soaked in a melatonin solution (50, 100, and 200 µM) for 30 min and then stored at 4 °C under 90% relative humidity for 25 days. The results indicated that melatonin treatment delayed the post-harvest senescence of asparagus and maintained high chlorophyll and vitamin C levels. Melatonin treatment hindered phenylalanine ammonia-lyase and peroxidase activities and reduced lignin content, thereby delaying the increase in firmness. Moreover, melatonin treatment enhanced catalase and superoxide dismutase activities, leading to reduced hydrogen peroxide content. These results indicate that melatonin treatment can be used to maintain the post-harvest quality and prolong the shelf life of green asparagus.

Erratum to: Comparisons of Chemical Composition, Flavor and Bioactive Substances between Korean and Imported Velvet Antler Extracts.

[This corrects the article DOI: 10.5851/kosfa.2021.e4.].

Comparisons of Chemical Composition, Flavor and Bioactive Substances between Korean and Imported Velvet Antler Extracts.

The aim of this study was to compare the antioxidant activity, chemical composition, flavor and bioactive compounds between Korean and imported velvet antlers (VAs)-derived extracts. The Korean (KVA), Russian (RVA) and New Zealand (NZVA) VAs (n=24 each, dry form) purchased from a local supplier were used in the investigation. After extracting with water (750 g VA with 6,000 mL water) for 20 h at 95°C, the VA extracts (VAE) were then used for analysis of antioxidant activity, amino acids (AAs), flavor and bioactive compounds. Compared to the RVA and NZVA, the KVA extract showed significantly higher 2,2-diphenyl 1 picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radicals scavenging activities (p<0.05). Significantly higher Fe content was found in the KVA while, higher Mn, Zn and Ca contents were found in the RVA (p<0.05). Twenty AAs were detected in all three VAEs and some of them (e.g., glycine and alanine) were higher in the KVA (p<0.05). A higher diversity (quality and quantity) of flavor compounds was found in the KVA extract compared to the imported VAs-derived extracts. Over six hundred metabolic compounds were identified in the VAEs. Among them, 412 compounds were commonly found in all the VAE types while, 109, 107, and 84 biomarker compounds were only found in the KVA, NZVA, and RVA extracts, respectively. Based on the results obtained in this study, it may be concluded that the country of origin partly affected the antioxidant activity, chemical composition, flavor and bioactive compounds of the VAEs.

Mixed Reality Tabletop Gameplay: Social Interaction With a Virtual Human Capable of Physical Influence.

In this article, we investigate the effects of the physical influence of a virtual human (VH) in the context of face-to-face interaction in a mixed reality environment. In Experiment 1, participants played a tabletop game with a VH, in which each player takes a turn and moves their own token along the designated spots on the shared table. We compared two conditions as follows: the VH in the virtual condition moves a virtual token that can only be seen through augmented reality (AR) glasses, while the VH in the physical condition moves a physical token as the participants do; therefore the VH's token can be seen even in the periphery of the AR glasses. For the physical condition, we designed an actuator system underneath the table. The actuator moves a magnet under the table which then moves the VH's physical token over the surface of the table. Our results indicate that participants felt higher co-presence with the VH in the physical condition, and participants assessed the VH as a more physical entity compared to the VH in the virtual condition. We further observed transference effects when participants attributed the VH's ability to move physical objects to other elements in the real world. Also, the VH's physical influence improved participants' overall experience with the VH. In Experiment 2, we further looked into the question how the physical-virtual latency in movements affected the perceived plausibility of the VH's interaction with the real world. Our results indicate that a slight temporal difference between the physical token reacting to the virtual hand's movement increased the perceived realism and causality of the mixed reality interaction. We discuss potential explanations for the findings and implications for future shared mixed reality tabletop setups.

Complexation of methyl salicylate with ß-cyclodextrin and its release characteristics for active food packaging.

A series of methyl salicylate (MeSA)/ß-cyclodextrin (ß-CD) inclusion complexes (ICs) were prepared at different MeSA concentrations by the co-precipitation method using methyl salicylate for maintaining the quality of fresh produce. The formation of IC was confirmed through FTIR, 1H NMR, TGA, and SEM measurements. Among the grades applied, IC with 1:1 grade showed the highest MeSA entrapment efficiency (59%). The release rate of MeSA from an IC was greater at higher temperature and higher relative humidity. In addition, the MeSA release from ICs of all grades followed a diffusive nature and first-order kinetics at 25 °C under all RH conditions, except at 7 °C. These results indicate that the use of a MeSA/ß-CD IC in active packaging applications can effective maintain the quality of fresh produce.

Foveation Pipeline for 360° Video-Based Telemedicine.

Pan-tilt-zoom (PTZ) and omnidirectional cameras serve as a video-mediated communication interface for telemedicine. Most cases use either PTZ or omnidirectional cameras exclusively; even when used together, images from the two are shown separately on 2D displays. Conventional foveated imaging techniques may offer a solution for exploiting the benefits of both cameras, i.e., the high resolution of the PTZ camera and the wide field-of-view of the omnidirectional camera, but displaying the unified image on a 2D display would reduce the benefit of "omni-" directionality. In this paper, we introduce a foveated imaging pipeline designed to support virtual reality head-mounted displays (HMDs). The pipeline consists of two parallel processes: one for estimating parameters for the integration of the two images and another for rendering images in real time. A control mechanism for placing the foveal region (i.e., high-resolution area) in the scene and zooming is also proposed. Our evaluations showed that the proposed pipeline achieved, on average, 17 frames per second when rendering the foveated view on an HMD, and showed angular resolution improvement on the foveal region compared with the omnidirectional camera view. However, the improvement was less significant when the zoom level was 8× and more. We discuss possible improvement points and future research directions.

Effects of Unaugmented Periphery and Vibrotactile Feedback on Proxemics with Virtual Humans in AR.

In this paper, we investigate factors and issues related to human locomotion behavior and proxemics in the presence of a real or virtual human in augmented reality (AR). First, we discuss a unique issue with current-state optical see-through head-mounted displays, namely the mismatch between a small augmented visual field and a large unaugmented periphery, and its potential impact on locomotion behavior in close proximity of virtual content. We discuss a potential simple solution based on restricting the field of view to the central region, and we present the results of a controlled human-subject study. The study results show objective benefits for this approach in producing behaviors that more closely match those that occur when seeing a real human, but also some drawbacks in overall acceptance of the restricted field of view. Second, we discuss the limited multimodal feedback provided by virtual humans in AR, present a potential improvement based on vibrotactile feedback induced via the floor to compensate for the limited augmented visual field, and report results showing that benefits of such vibrations are less visible in objective locomotion behavior than in subjective estimates of co-presence. Third, we investigate and document significant differences in the effects that real and virtual humans have on locomotion behavior in AR with respect to clearance distances, walking speed, and head motions. We discuss potential explanations for these effects related to social expectations, and analyze effects of different types of behaviors including idle standing, jumping, and walking that such real or virtual humans may exhibit in the presence of an observer.

Learning Curve of Internal Fixation for Nondisplaced Femoral Neck Fractures: A Cumulative Sum Analysis.

BACKGROUND: The purpose of this study was to determine whether there is a learning curve for internal fixation for nondisplaced femoral neck fractures using the cumulative sum (CUSUM) technique. We applied the CUSUM technique in monitoring performance of a single surgeon in internal fixation for nondisplaced femoral neck fractures. METHODS: Fifty consecutive patients who underwent internal fixation for nondisplaced femoral neck fractures were evaluated retrospectively. Loss of fixation within 6 months postoperatively was considered as failure of treatment. Patients were stratified into the early experience group (cases 1 to 25) and the late experience group (cases 26 to 50). The CUSUM method was used to analyze the learning curve. RESULTS: There was no failure of treatment during study period. The operation time became shorter with experience. Using the CUSUM analysis to plot the learning curve, there was no significant learning curve observed for multiple pinning for nondisplaced femoral neck fractures. CONCLUSIONS: The CUSUM analysis revealed there was no obvious learning curve to become proficient at internal fixation for nondisplaced femoral neck fractures, if technical principles were followed during the procedure.

Electrokinetic settling and sedimentation behavior of cohesive soils in dilute suspension.

In this study, the electrokinetic (EK) effects on settling behavior of clayey soils under different electrolyte solution, electric field strength, and moisture content were evaluated using kaolin and natural marine clay. A number of laboratory-scale column experiment were carried out in order to examine the effects of electrophoresis and electro-osmosis during settling processes. The settling velocity under different electrolyte solution was found to become faster resulting from the formation of floc due to the contraction of electrical double layer. The electrically induced surface settlement was faster in settling rate and greater in magnitude by comparison with that under the conventional gravitational sedimentation. The effects of electrophoresis on settling behavior become significant from the beginning of hindered settling stage due to the influence of electrochemical interactions between the charged clay particles.

The role of Di(2-ethylhexyl)phosphoric acid as a cosurfactant on the morphology control of mesoporous silica microspheres.

Synthesis of mesoporous silica microspheres larger than 10 microm via surfactant template approach has rarely been reported. According to the previous studies, particle morphologies were highly variable, depending on the synthesis conditions and impeller design such as impeller type, size, and agitation speed. A new robust surfactant-template synthesis strategy for the stable suspension of large silica microspheres was investigated by introducing an additional cosurfactant. Di(2-ethylhexyl)phosphoric acid (HDEHP) as a cosurfactant played a key role in suspension stabilization without distorting the spherical morphology as well as in the formation of uniform pore structures. High quality of mesoporous silica microspheres was obtained and compared with the Kosuge's silica under different conditions such as stirring rate, acid concentration, the amount of solvent in a mother liquor.