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It has been supposed that the interplay of elasticity and activity plays a key role in triggering the non-equilibrium behaviors in biological systems. However, the experimental model system is missing to investigate the spatiotemporally dynamical phenomena. Here, a model system of an active chain, where active eccentric-disks are linked by a spring, is designed to study the interplay of activity, elasticity, and friction. Individual active chain exhibits longitudinal and transverse motions; however, it starts to self-rotate when pinning one end and self-beat when clamping one end. In addition, our eccentric-disk model can qualitatively reproduce such behaviors and explain the unusual self-rotation of the first disk around its geometric center. Furthermore, the structure and dynamics of long chains were studied via simulations without steric interactions. It was found that a hairpin conformation emerges in free motion, while in the constrained motions, the rotational and beating frequencies scale with the flexure number (the ratio of self-propelling force to bending rigidity), χ, as ∼(χ)4/3. Scaling analysis suggests that it results from the balance between activity and energy dissipation. Our findings show that topological constraints play a vital role in non-equilibrium synergy behaviors. [ABSTRACT FROM AUTHOR]

ABSTRACT In this paper, the Smoothed Particle Hydrodynamics method is used to simulate the dynamic response of the floating offshore wind turbine mooring system in a complex marine environment by using its advantages of dealing with free surface flow and fluid–structure interaction. The single‐cable mooring system and the double‐cable mooring system are introduced into the numerical simulation model of fluid–solid coupling interaction. The first‐order irregular wave and the second‐order regular wave are used to simulate different wave conditions. The operating state of the platform in these two cases is analyzed, and the accurate data such as the velocity change of the geometric center of the platform and the change of six degrees of freedom are obtained. Using visual processing and data analysis, it is found that the optimized double‐cable mooring system structure improves the vibration reduction ability of the platform. [ABSTRACT FROM AUTHOR]

Supervised polarimetric synthetic aperture radar (PolSAR) image classification demands a large amount of precisely labeled data. However, such data are difficult to obtain. Therefore, many unsupervised methods have been proposed for unsupervised PolSAR image classification. The classification maps of unsupervised methods contain many high-confidence samples. These samples, which are often ignored, can be used as supervisory information to improve classification performance on PolSAR images. This study proposes a new unsupervised PolSAR image classification framework. The framework combines high-confidence superpixel pseudo-labeled samples and semi-supervised classification methods. The experiments indicated that this framework could achieve higher-level effectiveness in unsupervised PolSAR image classification. First, superpixel segmentation was performed on PolSAR images, and the geometric centers of the superpixels were generated. Second, the classification maps of rotation-domain deep mutual information (RDDMI), an unsupervised PolSAR image classification method, were used as the pseudo-labels of the central points of the superpixels. Finally, the unlabeled samples and the high-confidence pseudo-labeled samples were used to train an excellent semi-supervised method, similarity matching (SimMatch). Experiments on three real PolSAR datasets illustrated that, compared with the excellent RDDMI, the accuracy of the proposed method was increased by 1.70%, 0.99%, and 0.8%. The proposed framework provides significant performance improvements and is an efficient method for improving unsupervised PolSAR image classification. [ABSTRACT FROM AUTHOR]

Background: Colonic transit (CT) measured by validated scintigraphy using 111In‐labeled activated charcoal particles is summarized using geometric center (GC) of isotopic distribution in four colonic regions and stool at 24 and 48 h. Diagnosis of rapid CT is currently based on GC24 ≥4.4 in females and >4.7 in males, which lack sensitivity. Our aim was to evaluate, in patients with chronic diarrhea with normal CT by GC24 and GC48, the diagnostic utility of CT change (∆GC) relative to sex‐matched normal values. Methods: We evaluated two adult patient cohorts: 701 clinical patients (1994–2023) with chronic diarrhea and 76 research participants with irritable bowel syndrome with diarrhea (N = 63) or bile acid diarrhea (BAD, N = 13). Results of ∆GC were compared to 220 healthy controls' 95th percentiles (%ile) (≥2.0 females and ≥2.2 males). In the research cohort, we also analyzed (Spearman correlation) colonic ∆GC with ascending colon emptying T1/2 (AC T1/2), average stool frequency and consistency based on a daily diary, total fecal bile acid (BA) concentration, and % primary BA in a single stool sample. Key Results: Among 701 clinical patients with normal GC24, 160 (22.3%) had rapid CT based on ∆GC 95th %ile in health. Among 76 research participants, an additional 20.6% IBS‐D and 23% BAD had rapid CT ∆GC. Younger age and absence of diabetes mellitus were predictive of rapid ∆GC. ∆GC significantly correlated with AC T1/2 and with fecal BA. Conclusions & Inferences: ∆GC identified an additional 21%–23% patients with rapid colonic transit among patients with diarrhea and normal GC24. [ABSTRACT FROM AUTHOR]

Let R symbolize a prime ring with a characteristic other than 2, and let ρ (η 1 , ... , η n) represent a non-central multilinear polynomial over the extended centroid C of R . Assuming the presence of three b-generalized skew derivations on R , namely D 1 , D 2 , and D 3 that satisfy the equation D 1 (ρ) ρ + ρ D 2 (ρ) = D 3 (ρ 2) for all ρ = ρ (η 1 , ... , η n) , where η 1 , ... , η n are elements of R . In this research paper, our goal is to elucidate all potential configurations of D 1 , D 2 , and D 3 . [ABSTRACT FROM AUTHOR]

Let L be a Lie algebra and let A be an associative commutative algebra with unity, both over the same field F. We consider the following question. Is every generalized derivation (resp. quasiderivation) of L ⊗ A the sum of a derivation and a map from the centroid of L ⊗ A , if the same holds true for L? [ABSTRACT FROM AUTHOR]

This paper discusses a new issue named domain generalization of fast motion planning in 3D environments, which benefits agility-required robot applications such as autonomous driving and uncrewed aerial vehicle obstacle avoidance flight. The existing work shows that conventional spatial search-based planning algorithms cannot meet the real-time requirement due to high time costs. The end-to-end neural network-based methods achieve an excellent balance between performance and planning speed in the seen environments, but are hard to transfer to new scenarios. To overcome this limitation, we propose a novel Robust Environment Encoder (Ro2En) approach to domain generalization of fast motion planning. Specifically, by demonstrating the reconstructed environment, we find that the previous environment encoder cannot encode the volume information properly, i.e., a volume collapse ensues, which leads to noisy environment modeling. Inspired by this observation, a dual-task auto-encoder is developed. It can not only reconstruct the point cloud of the obstacles, but also align their geometric centers. Experiment results showed that in the new scenarios, Ro2En outperformed previous state-of-the-art conventional and neural alternatives with a much smaller performance variation. [ABSTRACT FROM AUTHOR]

Introduction: We studied the postural behaviour of a 52-year-old professional mountain climber who underwent bilateral amputation of all five toes after severe frostbite. Methods: Two tasks were examined: static posturography (SP) and gait initiation (GI), both performed barefoot and with prosthetic shoes. During SP, the participant kept the upright stance for 30 s while an optoelectronic system with reflective markers recorded feet position and body sway, and two force plates measured the Center of Pressure (CoP) displacement and Ground Reaction Force (GRF) of each foot. During GI, the participant stood on the force plates for at least 10 s and then spontaneously started walking, while optoelectronic system was used to monitor heel-off events; wireless EMG probes recorded the anticipatory postural adjustments (APAs) in trunk and lower limb muscles. Results: Compared to shod condition, during barefoot SP the participant showed a reduced anteroposterior (AP) and mediolateral (ML) extension of the Base of Support (BoS), and the whole-body CoP shifted about 7 mm more anteriorly, approaching the "safer" geometric center of the BoS. Despite this difference, the AP and ML ranges of CoP oscillations were similar in both conditions. In GI, the trunk dorsal muscles showed different APA patterns: when barefoot they were excitatory in the trailing and inhibitory in the leading side while they were bilaterally inhibitory when shod. Discussion: In parallel to CoP shift toward a "safer" position in SP, in barefoot GI the body rotation toward the trailing side may reveal a more "cautious" approach; this also shows that different postural strategies may be adopted in GI by one and the same individual. [ABSTRACT FROM AUTHOR]

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The notion of Fréchet mean (also known as “barycenter”) network is the workhorse of most machine learning algorithms that require the estimation of a “location” parameter to analyse network-valued data. In this context, it is critical that the network barycenter inherits the topological structure of the networks in the training dataset. The metric-which measures the proximity between networks-controls the structural properties of the barycenter. This work is significant because it provides for the first time analytical estimates of the sample Fréchet mean for the stochastic blockmodel, which is at the cutting edge of rigorous probabilistic analysis of random networks. We show that the mean network computed with the Hamming distance is unable to capture the topology of the networks in the training sample, whereas the mean network computed using the effective resistance distance recovers the correct partitions and associated edge density. From a practical standpoint, our work informs the choice of metrics in the context where the sample Fréchet mean network is used to characterize the topology of networks for network-valued machine learning. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a high-altitude multi-drone multi-target (HAMDMT) tracking method called STCA, which aims to collaboratively track similar targets that are easily confused. We approach this challenge by categorizing the HAMDMT tracking into two principal tasks: Single-Drone Tracking and Cross-Drone Association. Single-Drone Tracking employs positional and appearance data vectors to overcome the challenges arising from similar target appearances within the field of view of a single drone. The Cross-Drone Association employs image-matching technology (LightGlue) to ascertain the topological relationships between images captured by disparate drones, thereby accurately determining the associations between targets across multiple drones. In Cross-Drone Association, we enhanced LightGlue into a more efficacious method, designated T-LightGlue, for cross-drone target tracking. This approach markedly accelerates the tracking process while reducing indicator dropout. To narrow down the range of targets involved in the cross-drone association, we develop a Common View Area Model based on the four vertices of the image. Considering to mitigate the occlusion encountered by high-altitude drones, we design a Local-Matching Model that assigns the same ID to the mutually nearest pair of targets from different drones after mapping the centroids of the targets across drones. The MDMT dataset is the only one captured by a high-altitude drone and contains a substantial number of similar vehicles. In the MDMT dataset, the STCA achieves the highest MOTA in Single-Drone Tracking, with the IDF1 system achieving the second-highest performance and the MDA system achieving the highest performance in Cross-Drone Association. [ABSTRACT FROM AUTHOR]

This paper studies the robust vertex centdian location problem on tree networks with interval edge lengths. To obtain a robust solution, we use the minmax regret criterion. First, we obtain atmost n worst case scenario for each pair of vertices on tree networks. Then we reduce this number to log n . Finally, the total time for obtaining a robust solution is equal to O (n 4) . This time is reduced to O (n 3 log n) by using the property of binary search tree and weighted centroid. [ABSTRACT FROM AUTHOR]

Recently, UWB-based technology providing centimeter-level accuracy has been developed and widely utilized in indoor real-time location tracking systems. However, location accuracy varies due to factors such as frequency interference, collisions, reflected signals, and whether line-of-sight (LOS) conditions are met, and it can be challenging to ensure high accuracy in specific environments. Fortunately, when anchor positions are fixed, the locations of large obstacles such as columns or furniture remain relatively stable, leading to similar patterns of positioning bias at specific points. This study proposes an algorithm that corrects inaccurate positioning to more closely reflect the actual location based on bias and deviation maps generated using natural neighbor interpolation. Initially, positioning bias and deviations at specific points are sampled, and bias and deviation maps are created using natural neighbor interpolation. During location tracking, the algorithm detects candidate clusters and determines the centroid to estimate the actual location by applying the bias and deviation maps to the measured positions derived through trilateration. To validate the proposed algorithm, experiments were conducted in a non-LOS (NLOS) indoor environment. The results demonstrate that the proposed algorithm can reduce the positioning bias of a UWB-based RTLS by approximately 71.34% compared to an uncalibrated system. [ABSTRACT FROM AUTHOR]

The article "Actuation manifold from snapshot data" in the Journal of Fluid Mechanics introduces a data-driven approach to analyze controlled flows using isometric mapping and neural networks. It focuses on a fluidic pinball configuration with three cylinders at Reynolds number 30, revealing a five-dimensional manifold with minimal error. The study uncovers key parameters related to vortex shedding and actuation, offering valuable insights into fluid mechanics. The document also discusses various research papers on wake analysis, vortex shedding stabilization, machine learning for fluid control, and nonlinear dimensionality reduction, providing a comprehensive overview for researchers in the field. [Extracted from the article]

Comprehensive Summary Two families of cyclopentadienyl (Cp)/carboranyl heteroleptic sandwiched organolanthanide complexes, namely [Ln{η5:σ‐Me2C(C5H4)(C2B10H10)}2][Li(DME)3] (1Ln, Ln = Tb, Dy, Ho, Er) and [2‐THF‐2'‐(μ2‐Cl)Li(THF)3‐2,2'‐Ln(nido‐1,7‐C2B9H11)Cp*] (2Dy), were synthesized. Family of 1Ln has been proposed based on the mixing‐ligands idea by linking Cp and nido‐dicarborllide. However, the carborane cage of [Me2C(C5H4)(C2B10H10)]2− deprotons and forms a mono‐C− anion rather than deboron to form dicarborllide dianion. Hence, the family of 1Ln features a dysprosocenium skeleton with extra two coordination of C− anions of carborllides. Such coordination geometry is more like a tetrahedron if abstracting the centroids of two coordinated Cp rings. In this cubic‐type geometry, no significant magnetic axiality is presented; only 1Dy and 1Tb show field‐induced slow magnetic relaxation behavior below 10 K. Inspired by 1Ln, the free pentamethylcyclopentadienyl (Cp*−) and nido‐dicarborllide ligands are used to sandwich central Dy3+ ion, achieving heteroleptic complex 2Dy. The bending angle by linking the centroid of Cp*−, Dy3+ and C2B32− in 2Dy is increased to 132.8(1)°. As such, the effective energy barrier for magnetic reversal (Ueff) and magnetic blocking temperature TB (ZFC) are both increased (Ueff = 616(10) K; TB = 6 K). The effort of further enhancing Ueff and TB in such heteroleptic organolanthanide sandwiches should rely on keeping increasing the ligand axiality. [ABSTRACT FROM AUTHOR]

Models of migratory behavior predict trade‐offs between fitness costs and benefits with respect to migration distance. Shorter migration distances may confer a fitness benefit by facilitating earlier breeding, however this is rarely investigated. We tested this hypothesis using a large‐scale geolocation (GLS) dataset from 109 rhinoceros auklets (Cerorhinca monocerata), a differentially migrating seabird, that was tagged at 12 breeding colonies along the Pacific Coast of North America, spanning southern California to the eastern Aleutian Islands, Alaska. Using GLS‐based position estimates, we determined the geographic centroid of the pelagic areas occupied by birds in winter (1 January–28 February) and then calculated the distance between their wintering centroids and colony of origin. We then used GLS light‐intensity and salt‐water immersion (wet/dry) data to determine each individual's date of egg‐laying the following spring. Rhinoceros auklets were very widely distributed across the northeastern Pacific Ocean in winter. Among all individuals, the distance between winter centroids and breeding colonies ranged from < 100 to > 2500 km, being greater among individuals originating from colonies at higher latitudes. As predicted, migration distance and colony latitude were positively related to lay date: after accounting for colony‐level differences in phenology, individuals that migrated shorter distances tended to lay their eggs earlier, a pattern that emerged across all populations. Our study links the migration distance of rhinoceros auklets to a fitness‐related outcome, underscoring the selective pressure that migration exerts on subsequent breeding activity. [ABSTRACT FROM AUTHOR]

We calculate focal mechanisms and centroid depths for deep‐focus earthquakes (DFEs) along the Peru‐Brazil border. We obtained a total of 28 focal solutions for events with magnitudes between 4.2 and 7.5 Mw and occurring between 2014 and 2022. Focal mechanisms indicate predominance of normal faulting, demonstrating a rather uniform down‐dip compression (DDC) regime within the plate. The orientations of the nodal planes suggest that earthquakes tend to occur along faults parallel to the local slab strike, although other fault types are documented. Stress orientations derived from the focal mechanisms agree with patterns expected if faulting were initiated by transformational faulting on a metastable olivine wedge (MOW) under DDC. Centroid depths range between 557 and 659 km, defining a narrow seismic zone within the lower portion of the subducting plate and an aseismic upper portion. We suggest that DFEs nucleate through transformational faulting within a narrow MOW preserved at a colder slab segment right above the lower mantle and juxtaposed to a shallower, warmer segment at around 500 km depth. This thermal complexity was possibly produced through flat subduction initiated by the subduction of the Nazca Ridge. We speculate that subduction of other aseismic ridges is possibly controlling the thermal state of the Nazca slab as a whole and, consequently, the depth distribution of DFEs along the South America subduction front. Plain Language Summary: Aiming to better understand the dynamics of deep earthquakes, we studied mechanisms and depths for deep‐focus earthquakes (DFEs) from 2014 to 2022 at the Peru‐Brazil border. We determined focal mechanisms for 28 events, which indicate the predominance of normal faulting and demonstrate that the Nazca plate is under down‐dip compression (DDC). Stresses from these mechanisms agree with patterns expected if faulting were initiated by the transformational faulting mechanism on a metastable olivine wedge (MOW) under DDC. Events' depths ranged from 557 to 659 km, defining a narrow seismic zone within the plate. We suggest that DFEs are nucleating through transformational faulting in a narrow MOW preserved at a colder slab segment right above the lower mantle and connected to a warmer segment at around 500 km depth. Thermal complexity possibly resulted from the flat subduction associated with the Nazca Ridge. We speculate that subduction of other aseismic ridges is possibly controlling the thermal state of the Nazca slab as a whole and, consequently, the depth distribution of DFEs along the South America subduction front. Key Points: We determined focal mechanisms and centroid depths for 28 deep‐focus earthquakes along the Peru‐Brazil border from 2014 to 2022Deep‐focus earthquakes in South America are possibly nucleated from transformational faulting in a metastable olivine wedgeDepth distribution of deep‐focus earthquakes is possibly controlled by the subduction of the aseismic ridges and flat subduction [ABSTRACT FROM AUTHOR]

With the proliferation of vehicular mobility traces because of inexpensive on-board sensors and smartphones, utilizing them to further understand road movements have become easily accessible. These huge numbers of vehicular traces can be utilized to determine where to enhance road infrastructures such as the deployment of electric vehicle (EV) charging stations. As more EVs are plying today's roads, the driving anxiety is minimized with the presence of sufficient charging stations. By correctly extracting the various transportation parameters from a given dataset, one can design an adequate and adaptive EV charging network that can provide comfort and convenience for the movement of people and goods from one point to another. In this study, we determined the possible EV charging station locations based on an urban city's vehicular capacity distribution obtained from taxi and ride-hailing mobility GPS traces. To achieve this, we first transformed the dynamic vehicular environment based on vehicular capacity into its equivalent urban single snapshot. We then obtained the various traffic zone distributions by initially utilizing k-means clustering to allow flexibility in the total number of wanted traffic zones in each dataset. In each traffic zone, iterative clustering techniques employing Density-based Spatial Clustering of Applications with Noise (DBSCAN) or clustering by fast search and find of density peaks (CFS) revealed various area separation where EV chargers were needed. Finally, to find the exact location of the EV charging station, we last ran k-means to locate centroids, depending on the constraint on how many EV chargers were needed. Extensive simulations revealed the strengths and weaknesses of the clustering methods when applied to our datasets. We utilized the silhouette and Calinski–Harabasz indices to measure the validity of cluster formations. We also measured the inter-station distances to understand the closeness of the locations of EV chargers. Our study shows how CFS + k-means clustering techniques are able to pinpoint EV charger locations. However, when utilizing DBSCAN initially, the results did not present any notable outcome. [ABSTRACT FROM AUTHOR]

Indoor navigation has attracted significant attention from both academic and industrial perspectives. Indoor positioning is a critical component of indoor navigation. Several solutions or technologies have been proposed, such as Wi-Fi, UWB, and Bluetooth. Among them, Bluetooth Low Energy (BLE) is cost-effective, easily deployable, flexible, and efficient. This paper focuses on indoor positioning solely based on BLE. Motivated by two observations, namely, that (i) involving more anchor nodes can enhance positioning accuracy, and that (ii) narrowing the area for unknown location determination can also lead to improved accuracy, a new distance-based method, the Weighted Centroid of the Convex Polygon (WC-CP), is proposed. While it is generally acknowledged that incorporating more anchor nodes can enhance indoor positioning performance, the current state of the art lacks a robust methodology for selecting and utilizing these nodes. The WC-CP approach addresses this gap by introducing a systematic and efficient method for identifying and employing the most suitable anchor nodes. By avoiding nodes that could potentially introduce significant errors or lead to incorrect localization, our method ensures more accurate and reliable indoor positioning. The efficacy of WC-CP is demonstrated in an indoor environment, achieving an RMSE of 1.35 m. This result shows significant improvements over three state-of-the-art approaches, about 34.15% better than LSBM, 32.50% better than TWCBM, and 30.05% better than ITWCBM. These findings underscore the potential of WC-CP for enhanced accuracy and reliability in indoor positioning based on BLE. [ABSTRACT FROM AUTHOR]

Introduction: Whole gut transit scintigraphy (WGTS) can detect delayed colonic transit (CT), different types of CT delays, and assess upper GI tract transit. Aim: To delineate the frequency of different types of CT patterns in patients with chronic constipation (CC), determine the relationship between these CT patterns and upper GI tract transit abnormalities, and assess how symptoms relate to different colonic transit patterns. Methods: Retrospective review of patients who had WGTS for CC. Patients completed a modified PAGI-SYM questionnaire to assess symptoms. Patients ingested a standard solid (Tc-99m egg sandwich)–liquid (In-111 water) meal to assess solid meal gastric emptying (GE), liquid GE, small bowel transit (SBT), and geometric center of colonic activity at 24, 48, and 72h. Results: One hundred and eighty six patients underwent WGTS. Main symptoms were constipation (41%), nausea (24%), and bloating (22%). CT assessment showed 32% of patients had normal transit, 31% colonic inertia (CI), 28% functional rectosigmoid obstruction (FRS0), and 9% generalized slow colonic transit (GSCT). GE was delayed in 36%; more commonly in CI and FRSO. SBT was delayed in 19%; more commonly in GSCT and CI. Patients with CI had less bowel movements per week whereas patients with normal CT had more bm/week. Conclusions: In this series of patients with symptomatic constipation, WGTS assessment showed delayed colonic transit in 68% of patients, with 31% having colonic inertia, 28% a functional rectosigmoid obstruction pattern, and 9% generalized delay in colonic transit. Abnormalities in GE and SBT were present in 36 and 19%. WGTS is helpful to document delayed colonic transit (CT), assess the pattern of the delay in CT, and determine if there are upper GI transit abnormalities. [ABSTRACT FROM AUTHOR]

The present study continued to investigate whether the effects of length misperception caused by cross-shaped (formed by two pairs of the oppositely oriented Müller-Lyer wings) contextual distractors can be explained by the combined manifestation of two different (i.e., the Müller-Lyer and filled-space) geometric illusions of extent. In psychophysical experiments, the luminance of one pair of wings was randomly changed, while the luminance of the other pair remained constant. Two different distractor orientations were used—when the wings with constant luminance formed the right side of the cross or the left side, otherwise. To separately evaluate the manifestation of the Müller-Lyer illusion under different luminance conditions, two distracting crosses of the same orientation were attached to the lateral stimulus terminators in the first series of experiments. In the following four series, a single distracting cross (with different orientation) was attached to one of the lateral stimulus terminators and various combinations of the constant and background luminance were used. To interpret the experimental data, we used the basic computational principles of previously developed quantitative models of hypothetical visual mechanisms underlying the emergence of the Müller-Lyer illusion and the filled-space illusion. It was shown that the results of theoretical calculations adequately approximate the experimental curves obtained for all modifications of stimuli, which strongly supports the suggestion that the joint manifestations of these two illusions can be considered among the main factors determining the features of the illusion investigated. [ABSTRACT FROM AUTHOR]

In this study, several 3-dimensional (3-D) parameter estimation and localization algorithms for wireless near-field (NF) sources are proposed employing the uniform circular array (UCA) structure. In the single-base-station case, the algebraic relation is demonstrated between the azimuth angle under the far-field (FF) assumption and the actual NF source firstly. Secondly, two groups of antenna pairs are selected with distances less than half the wavelength, which are called short baselines in the interferometer method. The foregoing short-baseline method is qualified to localize an NF source. In addition, a long-baseline method is also proposed with further research. Two groups of antenna pairs with distances greater than half the wavelength are selected as two long baselines. In the multiple-base-stations case, another two novel algorithms are also proposed. The first one is the centroid algorithm, which is based on the centroid calculation of three estimated source locations. And the second one is the perpendicular foot algorithm, which takes the perpendicular foot within three estimated source locations as the final positioning location. Simulation results illustrate that the proposed algorithms can achieve higher localization accuracy than the conventional 3-D Root MUSIC method. Moreover, the long-baseline method performs better than the short-baseline method. And it is also shown that the proposed perpendicular foot algorithm shows better performance than the proposed centroid algorithm. [ABSTRACT FROM AUTHOR]

It is usually hard to obtain adequate annotated data for delivering satisfactory scene classification results. Semi-supervised scene classification approaches can transfer the knowledge learned from previously annotated data to remote sensing images with scarce samples for satisfactory classification results. However, due to the differences between sensors, environments, seasons, and geographical locations, cross-domain remote sensing images exhibit feature distribution deviations. Therefore, semi-supervised scene classification methods may not achieve satisfactory classification accuracy. To address this problem, a novel semi-supervised subcategory centroid alignment (SSCA)-based scene classification approach is proposed. The SSCA framework is made up of two components, namely the rotation-robust convolutional feature extractor (RCFE) and the neighbor-based subcategory centroid alignment (NSCA). The RCFE aims to suppress the impact of rotation changes on remote sensing image representation, while the NSCA aims to decrease the impact of intra-category variety across domains on cross-domain scene classification. The SSCA algorithm and several competitive approaches are validated on two datasets to demonstrate its effectiveness. The results prove that the proposed SSCA approach performs better than most competitive approaches by no less than 2% overall accuracy. [ABSTRACT FROM AUTHOR]

The characteristics of a bullet are closely related to its shooting accuracy. In actual shooting, the centroid and entry angle of the bullet always deviate from the ideal state. To study the influence of these two parameters on the movement of the bullet, a finite element model of the bullet movement inside the barrel was built based on a 5.8 mm small-caliber rifle to simulate the actual process of firing bullets. In this model, the pressure load of the real gunpowder gas on the bullet was considered. This model was also verified by experiments and the relative error is less than 1.5%. The result shows that the influence the centroid and entry angle of the bullet are mainly reflected in the amplitude and phase angle of the bullet swing angle. The larger the offsetting distance of cetroid is, the amplitude of the pitch and yaw angle are. The maximum magnitude of amplitude is 0.2°. The difference of swing angle in phase is equal to the difference in offsetting angle. The curve characteristics of different deviation angle are similar to the curve of bullet cetroid effect. The range of the pitch angle is -1°~0.9° and the range of the yaw angle is -0.9°~0.9°. [ABSTRACT FROM AUTHOR]

We consider the area-preserving Willmore evolution of surfaces ϕ that are close to a half-sphere with a small radius, sliding on the boundary S of a domain Ω while meeting it orthogonally. We prove that the flow exists for all times and keeps a "half-spherical" shape. Additionally, we investigate the asymptotic behavior of the flow and prove that for large times the barycenter of the surfaces approximately follows an explicit ordinary differential equation. Imposing additional conditions on the mean curvature of S, we then establish convergence of the flow. [ABSTRACT FROM AUTHOR]

Existing unsupervised person re-identification (Re-ID) methods use clustering to generate pseudo-labels that are generally noisy, and initializing the model with ImageNet pre-training weights introduces a large domain gap that severely impacts the model's performance. To address the aforementioned issues, we propose the data complement pseudo-label refinement and self-guided pre-training framework, referred to as DCSG. Firstly, our method utilizes image information from multiple augmentation views to complement the source image data, resulting in aggregated information. We employ this aggregated information to design a correlation score that serves as a reliability evaluation for the source features and cluster centroids. By optimizing the pseudo-labels for each sample, we enhance their robustness. Secondly, we propose a pre-training strategy that leverages the potential information within the training process. This strategy involves mining classes with high similarity in the training set to guide model training and facilitate smooth pre-training. Consequently, the model acquires preliminary capabilities to distinguish pedestrian-related features at an early stage of training, thereby reducing the impact of domain gaps arising from ImageNet pre-training weights. Our method demonstrates superior performance on multiple person Re-ID datasets, validating the effectiveness of our proposed approach. Notably, it achieves an mAP metric of 84.3% on the Market1501 dataset, representing a 2.8% improvement compared to the state-of-the-art method. The code is available at https://github.com/duolaJohn/DCSG.git. [ABSTRACT FROM AUTHOR]

The identification of damage to concrete bridge surfaces is of great significance to maintaining the durability and reliability of bridges. However, it is difficult to identify small areas of damage, especially in high-resolution images. To conduct damage identification research in a targeted manner, this paper proposes a method of multidamage identification in high-resolution images based on You Only Look Once version 5 (YOLOv5). In this paper, a data set labeled with four types of damage (crack, spallation, hole, and rebar) is used for training, validation, and testing. To ensure that the network adequately learns the damage features, the high-resolution images are cropped into subimages via the autoadaptive window cropping method (AWCM) proposed in this paper. The cropping method can crop images according to the label information and protect the damage features from destruction during the cropping process. To avoid overfitting, it is necessary to balance the volume of different types of damage. After balancing, the count for each category is as follows: crack (4,980), spallation (5,225), hole (5,211) and rebar (5,020). The balanced data set can be used to train the deep learning network and construct the multidamage identification model. After identification, the subimages, and the prediction boxes of damages in them are restored to their original high-resolution images. The results show that the mean average precision (mAP) of all classes is 94.2%, and the values for cracks, spallation, holes, and rebars are 86.9%, 98.1%, 92.3%, and 99.4%, respectively, which indicates that the proposed method outperforms the other three methods (inputting original images directly, the sliding window cropping method, and the random centroid cropping method). [ABSTRACT FROM AUTHOR]

Drug repositioning is a cost-effective approach to identifying new indications for existing drugs by predicting their associations with new diseases or symptoms. Recently, deep learning-based models have become the mainstream for drug repositioning. Existing methods typically regard the drug-repositioning task as a binary classification problem to find the new drug–disease associations. However, drug–disease associations may encompass some potential subcategories that can be used to enhance the classification performance. In this paper, we propose a prototype-based subcategory exploration (PSCE) model to guide the model learned with the information of a potential subcategory for drug repositioning. To achieve this, we first propose a prototype-based feature-enhancement mechanism (PFEM) that uses clustering centroids as the attention to enhance the drug–disease features by introducing subcategory information to improve the association prediction. Second, we introduce the drug–disease dual-task classification head (D3TC) of the model, which consists of a traditional binary classification head and a subcategory-classification head to learn with subcategory exploration. It leverages finer-grained pseudo-labels of subcategories to introduce additional knowledge for precise drug–disease association classification. In this study, we conducted experiments on four public datasets to compare the proposed PSCE with existing state-of-the-art approaches and our PSCE achieved a better performance than the existing ones. Finally, the effectiveness of the PFEM and D3TC was demonstrated using ablation studies. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) methods have been gaining momentum because they provide vast design and fabrication possibilities, increasing the accessibility of state-of-the-art hardware through recent developments in user-friendly computer-aided drawing/engineering/manufacturing (CAD/CAE/CAM) tools. However, in comparison to the conventional manufacturing methods, AM processes have some disadvantages, including the machining precision and fabrication process times. The first issue has been mostly resolved through the recent advances in manufacturing hardware, sensors, and controller systems. However, the latter has been widely investigated by researchers with different toolpath planning perspectives. As a contribution to these investigations, the present study proposes a toolpath planning method for AM, which aims to provide highly continuous yet distance-optimized solutions. The approach is based on the utilization of the signed distance field (SDF), clustering, and minimization of toolpath distances among cluster centroids. The method was tested on various geometries with simple closed curves to complex geometries with holes, which provides effective toolpaths, e.g., with relative distance reduction percentages up to 16.5% in comparison to conventional rectilinear infill patterns. [ABSTRACT FROM AUTHOR]

With the surge in object detection, Multi-Object Tracking (MOT) research has recently witnessed significant advancements. However, most previous studies have primarily focused on benchmarks involving distinguishing appearances and linear motion. In scenarios involving non-linear motion and similar appearances, these methods exhibit a drastic drop in performance. To address this issue, we propose WDTtrack, which incorporates spatiotemporal proximity, velocity orientation, and appearance similarity simultaneously. Firstly, we employ the Centroid Triplet Loss ReID (CTL) model to extract high-quality appearance embeddings. Second, we introduce Wider Bounding Box (W-BBox) and Direction Bank (DB) to capture abundant credible, and discriminative motion cues. Finally, we devise the Tracklet Recovery Mechanism (TRM) to facilitate long-term tracking maintenance. Extensive empirical results demonstrate that WDTtrack outperforms other trackers on the DanceTrack and SportsMOT dataset, highlighting its effectiveness and potential for further development. Specifically, WDTtrack achieves a 66.8 HOTA score, a 72.8 IDF1 score and a 55.9 AssA score on DanceTrack, and a 73.8 HOTA score, a 80.5 IDF1 score and a 64.3 AssA score on SportsMOT, substantially surpassing other non-Transformer algorithms. [ABSTRACT FROM AUTHOR]

Wireless sensor networks consist of numerous sensor nodes that monitor and send environmental data, such as temperature measurements and motion detection information, to a central station. Due to the nature of hop-by-hop data transmission in such networks, the failure of several nodes can adversely affect the functionality of the remaining healthy nodes, making the connection to the central station impossible. This study introduces the Hierarchical Agglomerative Clustering-Based Connectivity Restoration (HACCR) approach to address the problem of network reconnection after node failures. HACCR operates in two phases: backbone formation and recovery process. In the backbone formation phase, nodes exchange data packets to determine their locations and run the Hierarchical Agglomerative Clustering algorithm to form clusters. The clusters' geometric centers are then used to construct an Equivalent Graph, from which a Minimum Spanning Tree (MST) is derived using the Kruskal algorithm. In the recovery process, mobile nodes are deployed to restore connectivity by moving towards the cluster centers and establishing communication links along the MST. HACCR's performance is validated through comprehensive simulation studies, considering metrics such as the number of deployed mobile nodes, total traveled distance, and maximum distance traveled. The results demonstrate that HACCR outperforms baseline approaches in terms of efficiency and effectiveness. [ABSTRACT FROM AUTHOR]

Numerical simulations were conducted to investigate the wave features of subaerial granular landslide-generated impulse waves and their impact on slopes. A numerical solution was obtained by coupling smoothed particle hydrodynamics (SPH) and the discrete element method (DEM). Several predictive equations were tested for their applicability in predicting the maximum crest amplitude of impulse waves generated by slides of different shapes. The results indicated that the predictive model developed by Heller and Hager, utilising slide centroid impact velocity, showed favourable prediction accuracy for the maximum crest amplitude, almost independent of the slide shape at impact. Regarding the leading wave, although the wave profile and velocity distribution deviated significantly from a solitary wave of the same wave amplitude, the maximum run-up could be satisfactorily estimated using solitary wave theory. In addition, the increase in the maximum dynamic forces exerted by the impulse waves on the slope followed a power law with the incident wave amplitude. [ABSTRACT FROM AUTHOR]

To overcome the small sensitivities of luminescent manometers, Mn2+‐activated Zn2GeO4 green‐emitting phosphors with admirable manometric characteristics are synthesized. The structural stability of the studied samples is theoretically and experimentally investigated. Moreover, as pressure elevates, a huge spectral red‐shift and a broadening of the emission band are observed in studied samples, contributing to color‐tunable luminescence, i.e., from green to yellow, and ultimately to orange–red. Specifically, when pressure increases to 6.76 GPa, the emission band centroid shifts from 535.9 to 634.9 nm, leading to a superior sensitivity of dλ/dp = 21.3 nm/GPa. Whereas, in the same operating pressure range, the full width at half maximum (FWHM) of the emission band rises from 32.3 to 102.9 nm, resulting in unprecedentedly high sensitivity of dFWHM/dp = 17.0 nm/GPa. Furthermore, through analyzing the pressure‐dependent color coordinates, a maximum sensitivity of 29.43% GPa−1 is achieved, when x‐coordinate is adopted. Additionally, the applicability of the developed manometer is confirmed by a simple uniaxial pressure experiments to showcase its practical use in industrial and daily‐life purposes. Notably, the designed sensor exhibits the highest pressure sensitivities reported to date in different modes, namely, emission band centroid, FWHM and color coordinate, making supersensitive multimodal optical manometry a reality. [ABSTRACT FROM AUTHOR]

In the southwestern area of the Kurile Islands subduction zone, three large earthquakes including the Mw8.2 1969 and the Mw8.3 1994 Hokkaido Toho-oki earthquakes and the Mw7.8 1975 tsunami earthquake occurred in almost the same location. The three main shocks and their aftershocks were re-determined simultaneously using a double-difference earthquake location method, HypoDD. As a result, the 1969 and the 1975 main shocks and their aftershocks were concentrated near the upper surface of the subducting Pacific plate, indicating that both events were plate boundary megathrust earthquakes as shown by previous studies. On the other hand, the 1994 main shock and its aftershocks were distributed within the Pacific plate indicating that the 1994 event was an intraslab event as reported by previous studies. The result that interplate earthquakes and intraslab earthquakes could be appropriately distinguished is strong evidence that the accuracy of hypocenter determination is sufficiently high. The centroid moment tensor solution of the 1994 main shock has two nodal planes which are parallel or normal to the Kurile Trench. According to the high-resolution hypocenter distribution obtained in the present study, the aftershocks appear to locate on the nodal plane normal to the trench, suggesting that the source fault ruptured by the 1994 main shock was not parallel but normal to the Kurile Trench. Moreover, we found that the Coulomb failure stress change (ΔCFS) produced by the trench-normal fault plane is more likely to trigger the largest aftershock than ΔCFS produced by the trench-parallel fault plane. [ABSTRACT FROM AUTHOR]

Mock‐Lie algebras, a unique class of commutative algebras that satisfy the Jacobi identity, are gaining attention for their potential applications in various mathematical contexts. This study presents a matrix representation of the centroid for Mock‐Lie algebras in dimensions up to four, offering insights into their structure and interactions. By applying the centroid concept and utilizing matrix operations, we explore the relationships between matrix elements, leading to a better understanding of these algebras. Our findings aim to contribute to the growing interest in Mock‐Lie algebras and their role within the broader algebraic landscape. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of maintaining a stable mobile robot formation, steering and localizing all robots in an unknown dynamic environment consisting of multiple periodically moving objects, without the presence of a global positioning system or a robot tracking system. We propose a distributed observer such that each agent can estimate global positions of all mobile robots and that of moving landmarks in an unknown environment. By combining the proposed distributed observer with the distributed formation control and centroid tracking control law, we show that the formation shape can be maintained by utilizing its available relative measurements and the estimated relative measurements to its neighbors, and the group's centroid follows a desired trajectory. We present L2$$ {L}^2 $$ stability analysis of the closed‐loop system. Finally, we validate the proposed methods in a simulation result where a group of mobile robots can maintain a robust formation and maneuver in an unknown dynamic environment. [ABSTRACT FROM AUTHOR]

Ceracris kiangsu (Orthoptera: Arcypteridae), is greatly affected by climatic factors and exhibits strong adaptability, posing a serious threat to the ecological environment. Therefore, predicting its potential suitable habitat distribution provides a proactive theoretical basis for pest control. This study using the Biomod2 package of R simulated and predicted the current and future potential distribution, area changes, changes in the center points of suitable habitats, and niche shifts of C. kiangsu under two different greenhouse gas emission scenarios, SSP1-26 and SSP5-85. The results show that: (1) Currently, the high suitability areas for C. kiangsu are mainly distributed in Yunnan, Jiangxi, Hunan provinces in southern China and phongsaly province in northern Laos. In the future, the center of the suitable habitat distribution pattern of C. kiangsu will remain unchanged, primarily expanding outward from medium and high suitability areas. Additionally, significant suitable habitats for C. kiangsu were discovered in Southeast Asian countries without previous pest records. (2) Compared to the present, the overall suitable habitat area for C. kiangsu is expected to expand, particularly under the SSP5-85 climate change scenario. (3) In the SSP1-26 and SSP5-85 climate scenarios, the geometric center of the suitable habitat generally shows a trend of gradually shifting northeast. (4) Under different climate scenarios, the suitable habitat of C. kiangsu has highly overlapping, indicating that the suitable habitat of C. kiangsu in the invaded areas is broader than in its native regions. In conclusion, the research findings represent a breakthrough in identifying the potential distribution areas of C. kiangsu, which is of great practical significance for the monitoring and control of C. kiangsu pest infestation in China and Southeast Asian countries. [ABSTRACT FROM AUTHOR]

The discrete optimal transport (OT) problem, which offers an effective computational tool for comparing two discrete probability distributions, has recently attracted much attention and played essential roles in many modern applications. This paper proposes to solve the discrete OT problem by applying a squared smoothing Newton method via the Huber smoothing function for solving the corresponding KKT system directly. The proposed algorithm admits appealing convergence properties and is able to take advantage of the solution sparsity to greatly reduce computational costs. Moreover, the algorithm can be extended to solve problems with similar structures, including the Wasserstein barycenter (WB) problem with fixed supports. To verify the practical performance of the proposed method, we conduct extensive numerical experiments to solve a large set of discrete OT and WB benchmark problems. Our numerical results show that the proposed method is efficient compared to state-of-the-art linear programming (LP) solvers. Moreover, the proposed method consumes less memory than existing LP solvers, which demonstrates the potential usage of our algorithm for solving large-scale OT and WB problems. [ABSTRACT FROM AUTHOR]

The objective of this article is to establish a condition by which we are able to state that an ellipsoidal fragment formed by a plane cutting the ellipsoid can always contain a sphere in any position inside in it. A method to construct a chain of mutually tangent spheres inscribed in the ellipsoidal segment has been proposed. The locus of the centroid as well as the radii of the mutually tangent spheres have been computed. The prime concern of our work is to explore some geometrical properties of such a chain of spheres which includes the condition of inscribability of a sphere in any position inside the ellipsoid along with the computation of points of tangency between consecutive spheres. [ABSTRACT FROM AUTHOR]

Single-neutron adding data was collected in order to determine the distribution of the single-neutron strength of the 0 f 7 / 2 , 1 p 3 / 2 , 1 p 1 / 2 and 0 f 5 / 2 orbitals outside of Z = 16 , N = 18 , 34 S. The 34 S(d,p) 35 S reaction has been measured at 8 MeV/u to investigate cross sections to excited states in 35 S. Outgoing proton yields and momenta were analyzed by the Super-Enge Split-Pole Spectrograph in conjunction with the CeBrA demonstrator located at the John D. Fox Laboratory at Florida State University. Angular distributions were compared with Distorted Wave Born Approximation calculations in order to extract single-neutron spectroscopic overlaps. Spectroscopic overlaps and strengths were determined for states in 35 S up through 6 MeV in excitation energy. Each orbital was observed to have fragmented strength where a single level carried the majority. The single-neutron centroids of the 0 f 7 / 2 , 1 p 3 / 2 , 1 p 1 / 2 and 0 f 5 / 2 orbitals were determined to be 2360 - 40 + 90 keV, 3280 - 50 + 80 keV, 4780 - 40 + 60 keV, and ≳ 7500 keV, respectively. A previous discrepancy in the literature with respect to the distribution of the neutron 1 p 1 / 2 strength was resolved. The integration of the normalized spectroscopic strengths, up to 5.1 MeV in excitation energy, revealed fully-vacant occupancies for the 0 f 7 / 2 , 1 p 3 / 2 , and 1 p 1 / 2 orbitals, as expected. The spacing in the single-neutron energies highlighted a reduction in the traditional N = 28 shell-gap, relative to both the 1p spin-orbit energy difference ( N = 32 ) and the lower limit on the N = 34 shell spacing. [ABSTRACT FROM AUTHOR]

The scissors mode is investigated in the actinide region, including even–even superheavy nuclei up to 256 No, within the Time Dependent Hartree–Fock–Bogoliubov (TDHFB) approach. The solution of TDHFB equations by the Wigner Function Moments method predicts a splitting of the scissors mode into three intermingled branches due to spin degrees of freedom. Both the calculated energy centroid and integrated M1 strength in 254 No are in good agreement with the results of recent measurements performed by the Oslo method. The energy centroids and summed B(M1) values for other transuranium nuclides are predicted. [ABSTRACT FROM AUTHOR]

Introduction: No previous studies have implemented a standard blood flow restriction (BFR) training session in people with severe haemophilia (PwH), where this type of training has been contraindicated. Aims: The purpose of this study was to evaluate the tolerability, adverse events, and neuromuscular and perceptual responses to an acute session of low load (LL) knee extensions with BFR in PwH under prophylaxis. Methods: Eight PwH performed one LL‐BFR session with 40% arterial occlusion pressure (AOP). Perceptual responses and adverse effects were assessed, together with high‐density surface electromyography of vastus medialis (VM) and lateralis (VL). Results: Significant normalized root mean square differences were found within each set, but not between sets. Spatial distribution (centroid displacement (p >.05), modified entropy (VM, set two, cycles three and five, p =.032) and coefficient of variation (VM, set two, cycles four and five lower than cycle three (p =.049; p =.036)) showed changes within each set. Median frequency showed a slight increase during cycle four of set four (p =.030). Rate of perceived exertion slightly increased with each set while tolerability slightly decreased in the last set and fear of training with BFR generally decreased after the session. Conclusions: In PwH, a LL‐BFR session at 40% AOP is safe and feasible. Our results suggest that potential muscle impairments may blunt neuromuscular adaptations induced by BFR. [ABSTRACT FROM AUTHOR]

Based on the center of gravity and coupling analysis model, we calculate the spatial pattern and evolution characteristics of global economic, population and grain centers of gravity from 1960 to 2020, and analyze their coupling relationships and influencing factors. The results show that: (1) The centers of gravity of all three groups are obviously biased toward the northern hemisphere, which is closely related to the global distribution of land and sea, and the northern hemisphere has a larger land area and superior natural conditions than the southern hemisphere. The economic center of gravity is located in the northwest of the geometric center (0°, 0°), and the grain and population centers of gravity are located in the northeast of the geometric center; (2) The economic center of gravity moves eastward rapidly and with a large magnitude; the population center of gravity mainly moves from northwest to south, from northwest to southeast before 1990, and from northeast to the southwest after 1990, with a smaller movement; the grain center of gravity has a large jump and is the most unstable, and the regularity is not obvious;(3) The economic and grain centers of gravity are highly coupled; the grain and population centers of gravity are coupled, but not significantly; the economic and population centers of gravity are lowly coupled but in a gradually increasing state. [ABSTRACT FROM AUTHOR]

This study aimed to discuss the differences in technical characteristics between the lunge-style and squat-style jerk techniques and to reveal the adaptability of these techniques for individual weightlifters. A total of 52 attempts by 32 male weightlifters were selected, and the video data were digitized manually using the SIMI Motion 7.50 three-dimensional analysis system. The technical characteristics of the lunge split and squat jerk were fundamentally consistent during the pre-squat, force exertion, and inertia ascent phases. The primary differences between the lunge split and squat jerk techniques were observed during the squatting and support phases, including the vertical descent velocity of the barbell at the end of the squat shoulder-locking phase and the stability angles in the sagittal and coronal axes. The vertical velocity of the barbell at the end of the squat shoulder-locking phase was significantly greater in the squat style (−0.41 ± 0.17 vs. −0.88 ± 0.14) compared to the lunge style (t = 6.393, p < 0.05). The stability angle on the sagittal axis at the end of the squat-supporting phase in the lunge style was significantly greater (46.99 ± 3.23 vs. 13.64 ± 0.51) than that of the squat style (t = 45.639, p < 0.05). [ABSTRACT FROM AUTHOR]

When the tractor is undertaking the forestry carrying operation, due to the complex road conditions in the forest, it mostly runs at a low speed, has a high steering demand, and often has a load unit, so it pays more attention to its driving stability and steering sensitivity. In this paper, CarSim software is used to build the physical model and load unit model of the tractor, the control strategy of the tractor is designed based on Simulink software combined with the two-degree-of-freedom dynamic model, and the two-degree-of-freedom model of tractor is established. The braking torque feedback control is carried out by combining the yaw rate and the side deflection angle of centroid with the fuzzy control theory. In addition, the proportional control strategy of front and rear wheel angle is introduced according to the four-wheel steering mode of the tractor. Under the CarSim-Simlulink co-simulation platform, combined with the complex road conditions of forestry operations, the low-speed driving and steering experiments of tractor under different control strategies are carried out. The results show that the control strategy adopted in this paper can effectively reduce the steering radius of the tractor under complex road conditions, increase the steering speed, and limit the side deflection angle of centroid to a small range. The tractor has high stability, the steady state value of yaw rate is closer to the ideal state, and the steering is more sensitive. [ABSTRACT FROM AUTHOR]

Older adults have difficulty maintaining side-to-side balance while navigating daily environments. Losing balance in such circumstances can lead to falls. We need to better understand how older adults adapt lateral balance to navigate environment-imposed task constraints. How do older adults adjust mediolateral balance while walking along continually-narrowing paths, and what are the stability implications of these adjustments? Eighteen older (71.6±6.0 years) and twenty younger (21.7±2.6 years) healthy adults traversed 25 m-long paths that gradually narrowed from 45 cm to 5 cm. Participants switched onto an adjacent path when they chose. We quantified participants' lateral center-of-mass dynamics and lateral Margins of Stability (MoS L) as paths narrowed. We quantified lateral Probability of Instability (PoI L) as the probability that participants would take a laterally unstable (MoS L <0) step as they walked. We also extracted these outcomes where participants switched paths. As paths narrowed, all participants exhibited progressively smaller average MoS L and increasingly larger PoI L. However, their MoS L variability was largest at both the narrowest and widest path sections. Older adults exhibited consistently both larger average and more variable MoS L across path widths. Taken into account together, these resulted in either comparable or somewhat larger PoI L as paths narrowed. Older adults left the narrowing paths sooner, on average, than younger. As they did so, older adults exhibited significantly larger average and more variable MoS L , but somewhat smaller PoI L than younger. Our results directly challenge the predominant interpretation that larger average MoS L indicate "greater stability", which we argue is inconsistent with the principles underlying its derivation. In contrast, analyzing step-to-step gait dynamics, together with estimating PoI L allows one to properly quantify instability risk. Furthermore, the adaptive strategies uncovered using these methods suggest potential targets for future interventions to reduce falls in older adults. • Daily environments challenge older adults' ability to maintain lateral balance. • Healthy older and younger adults walked down continuously-narrowing paths. • Average lateral Margins-of-Stability (MoS L) yielded paradoxical results. • Larger average MoS L measures do not indicate "greater stability". • Probability-of-Instability (PoI L) properly captured peoples' instability risk. [ABSTRACT FROM AUTHOR]

To further reveal the blasting vibration frequency distribution characteristics induced by different initiation modes of the single borehole cylindrical charge, the PPV and Fourier dominant frequency formula under different initiation modes such as top initiation, bottom initiation, mid-point initiation, and two-point initiation are derived based on the Heelan equivalent unit short-column charge model. The results show that the dominant frequency distribution characteristics near the explosion source are as follows: two-point initiation > mid-point initiation > bottom initiation > top initiation; in the middle and far zones from the explosion source, the difference of dominant frequency induced by various initiation modes is insignificant; the attenuation curves of the dominant frequency of radial and vertical vibration abruptly change at the distance away from the blasting center of 20–50 m and 20–30 m, respectively. However, the curves of centroid frequency under different initiation modes attenuate smoothly with increasing distance, and the distribution rule is two-point initiation > mid-point initiation > bottom initiation > top initiation. In general, the influence of initiation mode on the particle vibration dominant frequency and centroid frequency is gradually weakened with increasing distance. Finally, the theoretical calculation is verified by the experimental data. [ABSTRACT FROM AUTHOR]

Let F, G, and H be generalized derivations with F ≠ 0 on a prime ring R of characteristic different from 2, with Utumi quotient ring U and extended centroid C such that for all r ∈ R n FH (f (r) 2) = F (f (r)) G (f (r)) + G (f (r)) F (f (r)) (1) where f(r) is a multilinear polynomial over C which is noncentral valued on R. In this article we prove that if R does not satisfy the standard identity s4 then either R satisfies (1) or f (x 1 , ... , x n) 2 is central valued on R. Also in both the cases we describe all the possible forms of F, G, and H. [ABSTRACT FROM AUTHOR]

A method of quickly obtaining an approximate solution to the traveling salesman problem (TSP) is suggested, where a dramatic computational speedup is guaranteed. The initial TSP is broken into open-loop TSPs by using a clustering method. The clustering method is based on either imposing a rectangular lattice on the nodes or dividing the dataset iteratively until the open-loop TSPs become sufficiently small. The open-loop TSPs are independent and so they can be solved in parallel without synchronization, whichever the solver is. Then the open-loop subroutes are assembled into an approximately shortest route of the initial TSP via the shortest connections. The assemblage pattern is a symmetric rectangular closed-loop serpentine. The iterative clustering can use the rectangular assembling approach as well. Alternatively, the iterative clustering can use the centroid TSP assembling approach, which requires solving a supplementary closed-loop TSP whose nodes are centroids of the open-loop-TSP clusters. Based on results of numerical simulation, it is ascertained that both the iterative clustering and rectangular cell clustering pattern are roughly equally accurate, but the latter is way more computationally efficient on squarish datasets. Fast approximation of the TSP shortest route serves as an upper bound. In addition, the route can be studied to find its bottlenecks, which subsequently are separated and another bunch of open-loop TSPs is approximately solved. For big-sized TSPs, where the balance of the accuracy loss and computational time is uncertain, the rectangular cell clustering pattern allows obtaining fast solution approximations on multitudinous non-synchronized parallel processor cores. [ABSTRACT FROM AUTHOR]

This study evaluated the efficacy of cooking processes in natural and forced convection systems, for ensuring microbiological safety in industrial‐scale ham production. The cold point of the tanks was determined by measuring the water temperature every 2 min, with a maximum variation of 1.4°C between different regions of the tanks. The calculation of the lethal value (Fcal) was carried out using Enterococcus faecalis as the target microorganism due to its high resistance to heat treatment. The cooking temperature was measured at the geometric center of the ham and, in both convection systems, it reached the Fref value (23.6 min), necessary to achieve a reduction of 8 log (8 D), with Fcal of 45.7 and 45 min of cooking in the natural and forced convection systems. Both convection systems achieved microbial reductions exceeding 15‐log cycles (15 D), surpassing regulatory requirements despite occasional core temperatures below standard thresholds. In both systems (natural and forced), the cold spot was found on the left side, at a lower height, and toward the front of the tank. After heat treatment, no microorganisms were detected in the ham cooked in natural or forced convection systems. Both systems (natural and forced convection) proved viable at an industrial scale, provided that appropriate cooking protocols are followed. Practical Applications: The practical applications of this study are significant for the food industry and regulatory bodies involved in food safety. These include quality assurance in ham production, food safety compliance, process optimization, risk mitigation, and guidance for industrial practices. Overall, this study has practical implications for improving food safety, quality control, and production efficiency in the ham industry. It fills a gap in validation studies on industrial‐scale ham cooking, providing valuable information for industry stakeholders and regulatory bodies alike. [ABSTRACT FROM AUTHOR]