Reachable Distance Research Articles

Quantum Entanglement in Nonlinear Coupler with Raman Process

This paper examines the possible quantum entanglement generated in a coupler system consisting of two waveguides, where one waveguide is nonlinear and Raman-active, while the other waveguide only undergoes linear processes. The analytical-perturbative method is employed to investigate the production of entangled states in the given system. The Hillery-Zubairy criterion is employed to examine the possible quantum entanglement between the two fundamental pump modes propagating in both waveguides. We explore the generation of quantum entanglement under different initial conditions and critical design parameters. The simulation results suggest a continuous entanglement that remains until a particular distance of interaction is reached. As the linear coupling parameter increases, the relationship between the maximum reachable distance for entanglement and the degree of entanglement becomes more complex. The study reveals that entanglement experiences significant fluctuations when there is a substantial frequency mismatch between the modes.

Regional comparison of specialized outpatient and (partial) inpatient pain medicine care in Germany

Chronic pain requires graduated and staged levels of care. The aim of this study is to provide aregional overview regarding the accessibility of specialized outpatient and (partial) inpatient pain medicine care from the patient's perspective in Germany. For 1000 model patients randomly generated from German postal code location combinations, the travelling time by car (individual transport, IT)and available public transport connections (PTC) to the nearest specialized outpatient and inpatient pain medicine clinics and units were assessed using aroute planner. Outpatient facilities (in apractice setting) were mostly realistically accessible depending on the proportion of pain treatment and the networking structure. University pain outpatient clinics were at a critically reachable distance with IT for 70% of the patients (80% with PTC) and had unrealistic accessibility for 49% of the patients with IT (68% with PTC). Interdisciplinary multimodal pain programs in day clinics were at a critically reachable distance for 68% of patients with IT (83% with PTC) and in 49% (75% PTC) at an unrealistic travelling time distance considering the more intense treatment requiring frequent travel. Full inpatient interdisciplinary multimodal treatment was more realistically reachable (IT 39% critical, 14% unrealistic, PTC 61% critical, 48% unrealistic). The results show relevant nationwide differences in the accessibility of facilities for specialized pain treatment depending on the place of residence. Considering the treatment of achronic condition with long-term therapeutic goals and the need for graduated care (outpatient and inpatient treatment), the results reveal apartly critical situation from the patient's perspective.

A mean shift algorithm incorporating reachable distance for spatial clustering

Spatial clustering is a widely used technique in spatial analysis that groups similar objects together based on their proximity in space. However, traditional clustering algorithms often fail to ensure the accessibility of cluster centers, which limits their validity in practical applications such as facility location problems. To address this issue, this article introduces a novel Mean Shift algorithm that incorporates reachable distance and an iterative mechanism to accurately locate cluster centers. The proposed algorithm initially labels clustering elements with road network coordinates to facilitate the calculation of reachable distance and the cluster center iterative mechanism. Subsequently, the mean shift vector function is modified to employ reachable distance as the measure of geographic reachable similarity. Unlike existing algorithms, our approach allows for cluster centers to be positioned independently of the clustering elements, guaranteeing geographical accessibility. Through simulation experiments, we demonstrate that our proposed algorithm not only outperforms existing methods in terms of solution quality, but also effectively addresses the limitations of disregarding geographical obstacles and unreachable cluster centers.

An identification method of chromatin topological associated domains based on spatial density clustering

The rapid development of high-throughput chromatin conformation capture (Hi-C) technology provides rich genomic interaction data between chromosomal loci for chromatin structure analysis. However, existing methods for identifying topologically associated domains (TADs) based on Hi-C data suffer from low accuracy and sensitivity to parameters. In this context, a TAD identification method based on spatial density clustering was designed and implemented in this paper. The method preprocessed the raw Hi-C data to obtain normalized Hi-C contact matrix data. Then, it computed the distance matrix between loci, generated a reachability graph based on the core distance and reachability distance of loci, and extracted clustering clusters. Finally, it extracted TAD boundaries based on clustering results. This method could identify TAD structures with higher coherence, and TAD boundaries were enriched with more ChIP-seq factors. Experimental results demonstrate that our method has advantages such as higher accuracy and practical significance in TAD identification.

PROMETHEUS: Probability in the Mediterranean of Tephra dispersal for various grain sizes. A tool for the evaluation of the completeness of the volcanic record in medial-distal archives

PROMETHEUS is a statistical tool that allows creating maps showing the probability of finding tephra deposits of different grain sizes, originating from eruptions of a specific volcanic source, at any location around the vent. It couples wind profiles at different heights in the Mediterranean area with terminal velocity of volcanic particles. The input parameters include the height of the eruption column (which characterizes the intensity of the eruption), wind statistics (directions and intensities), and tephra deposits of a selected grain size. In particular, we used the parameterizations provided by Costa et al. (2016) and performed simulations using the HAZMAP tephra dispersal model to determine the maximum reachable distances that tephra can cover under weak, medium, and strong wind conditions (e.g. 7, 30, and 70 m/s velocities at the tropopause) and with column heights of 10, 20, and 30 km, depositing of at least the loading corresponding to 0.1 mm (corresponding to cryptotephra). Three alternative configurations of the model are validated analyzing first the eruptive source of Somma Vesuvius, with the related explosive eruptions from 22 ka Pomici di Base to the 1944 eruption. A further validation is made by comparing the probabilistic maps with the tephrostratigraphy of known marine and terrestrial cores using standard test of proportions (binomial distributions) and the binary logistic regression model, statistically quantifying the effectiveness of the model against the tephrostratigraphy recorded within this time frame. Based on this validation, a preferred configuration of PROMETHEUS is selected. PROMETHEUS probability maps will guide the selection of sampling sites for specific tephra deposits and could also support the study of the completeness of overall eruption catalogs over time.

Development and Field Testing of a Wireless Data Relay System for Amphibious Drones

Amphibious (air and water) drones, capable of both aerial and aquatic operations, have the potential to provide valuable drone applications in aquatic environments. However, the limited range of wireless data transmission caused by the low antenna height on water and reflection from the water surface (e.g., 45 m for vertical half-wave dipole antennas with the XBee S2CTM, estimated using the two-ray ground reflection model) persists as a formidable challenge for amphibious systems. To overcome this difficulty, we developed a wireless data relay system for amphibious drones using the mesh-type networking functions of the XBeeTM. We then conducted field tests of the developed system in a large marsh pond to provide experimental evidence of the efficiency of the multiple-drone network in amphibious settings. In these tests, hovering relaying over water was attempted for extension and bypassing obstacles using the XBee S2CTM (6.3 mW, 2.4 GHz). During testing, the hovering drone (<10 m height from the drone controller) successfully relayed water quality data from the transmitter to the receiver located approximately 757 m away, but shoreline vegetation decreased the reachable distance. A bypassing relay test for vegetation indicated the need to confirm a connected path formed by pair(s) of mutually observable drones.

A Study on Strategies for Improving Participation in Urban Recreational Sports Activities Based on Multidimensional Data Analysis

Abstract Leisure sports, which aim to improve people’s health and quality of life, have vigorously developed with the continuous enrichment of social material wealth and the enhancement of people’s spiritual life needs. This paper uses multidimensional data analysis to measure the spatial vitality of urban residents’ leisure sports activities. We use distance decay and circle of life behavior theory to explain the behavioral basis of residents’ willingness to participate in leisure sports activities. We introduce a geographically weighted regression model, a geographic detector, a kernel density analysis method, and an accessibility index to study the specific characteristics of residents’ leisure sports activities, including spatial and temporal characteristics, leisure activity distribution, agglomeration characteristics, and preference selection. The research reveals distinct features in the spatial vitality of leisure and sports in Nanjing; the central urban area serves as the hotspot for activity intensity, and a discrepancy exists between the availability of sports and leisure resources and the overall spatial vitality. The average score for the spatial coordination of sports activities is 0.4928, with most communities falling below the medium threshold. The average reachable distance of residents’ sports activity space is 1732 m, significantly higher than the standard range of living circles (500~1500 m). Therefore, this paper proposes strategies for improving participation in urban leisure sports activities from five aspects: developing diversified activity contents, stimulating residents’ enthusiasm for leisure sports, media publicity and guidance, creating a good leisure sports consumption environment, and improving residents’ leisure sports space accessibility.

Late preterm and very preterm infants differ in the acquisition time and quantity of reaches with grasping at reaching onset: an exploratory study.

The onset of manual reaching allows the expansion of the infant's interaction with the environment. When born preterm, infants become vulnerable to problems in the development of reaching. However, it is still unknown whether there are differences in reaching according to the degree of prematurity. This study aimed to explore the differences in reaching acquisition and behavior between late preterm and very preterm infants, as well as whether age and clinical variables influence the results. This is an exploratory, comparative, observational study. In total, 24 infants were included soon after reaching onset; 12 infants were born late preterm (35.55 ± 0.67 gestational weeks) and 12 very preterm (30.60 ± 0.05 gestational weeks). Infants were placed in a baby seat, and a toy was placed at a reachable distance for 2 min. Reaching behavior was the primary variable; birth weight and length of hospital stay were secondary variables. The age of reaching onset was higher in the very preterm group. The proportion of reaches with grasping was higher in the late preterm group. These differences were affected by the lower birth weight and longer length of hospital stay in the very preterm group. The proportions of proximal and distal adjustments did not differ between groups. Very preterm infants presented disadvantages in the acquisition time and the number of reaches with grasping, but not in the proportions of proximal and distal adjustments of reaching, relative to late preterm infants. Group differences were influenced by clinical variables.

Aeroballistic optimization of long-range guided ammunition

PurposeThis paper aims to describe the use of optimization approaches to increase the range of near-future howitzer ammunition.Design/methodology/approachThe performance of a gliding projectile concept is assessed using an aeroballistic workflow, comprising aerodynamic characterization and flight trajectory computation. First, a single-objective optimization is run with genetic algorithms to find the maximal attainable range for this type of projectile. Then, a multi-objective formulation of the problem is proposed to consider the compromise between range and time of flight. Finally, the aerodynamic model used for the gliding ammunition is evaluated, in comparison with direct computational fluid dynamics (CFD) computations.FindingsApplying single-objective range maximization results in a great improvement of the reachable distance of the projectile, at the expense of the flight duration. Therefore, a multi-objective optimization is implemented in a second time, to search sets of parameters resulting in an optimal compromise between fire range and flight time. The resulting Pareto front can be directly interpreted and has the advantage of being useful for tactical decisions.Research limitations/implicationsThe main limitation of the work concerns the aerodynamic model of the gliding ammunition, which was initially proposed as an alternative to reduce significantly the computational cost of aerodynamic characterization and enable optimizations. When compared with direct CFD computations, this method appears to induce an overestimation of the range. This suggests future evolution to improve the accuracy of this approach.Originality/valueTo the best of the authors’ knowledge, this paper presents an original ammunition concept for howitzers, aiming at extending the range of fire by using lifting surfaces and guidance. In addition, optimization techniques are used to improve the range of such projectile configuration.

Bi-Level Coordinated Power System Restoration Model Considering the Support of Multiple Flexible Resources

When power systems encounter outages and large-scale blackouts, system restoration is critical and should be carried out with dedicated schemes. In this past, most studies divided the power system restoration into three stages (i.e., black-start zone partitioning, network reconfiguration, and load restoration) and deal with them separately. After that, few studies considering the three stages together were emerging while the support of multiple flexible resources, i.e., renewable energy source (RES), electric vehicle system (EVS) and energy storage system (ESS), were not considered comprehensively. Therefore, a bi-level coordinated power system restoration (BiCPSR) model is proposed in this work considering the support of multiple flexible resources. In the upper level, two network topology indices that describe the “reachability” and “shortest reachable distance” of buses in power systems, and the restoration characteristics of generators and loads are utilized for optimizing the start-up sequence of generators and network reconfiguration. In the lower level, the uncertainties of RES and EVS are considered by various scenarios and the support of multiple flexible resources is utilized cooperatively for accelerating the restoration process and maximizing the restorable load. Case studies on the revised IEEE 39-bus, WECC 179-bus and the actual Zhejiang power systems are performed to illustrate the basic features of the proposed model and its availability in bulk power systems. The comparisons between the proposed model and other models are also performed to illustrate the strengths of the proposed model.

MHV3SFCA: A new measure to capture the spatial accessibility of health care systems.

Good accessibility of health care services is essential to meet the needs of the population and ensure adequate health care coverage. It usually refers to two spatial dimensions: availability (competition between populations for the same medical supply) and reachability (distance between population and medical supply). Traditional indicators of health care accessibility usually fail to consider both of these components simultaneously. Floating-Catchment-Area (FCA) methods were developed to address these shortcomings. This study reviews the existing FCA methods and proposes the Modified Huff-based Variable 3 Steps Floating Catchment Area (MHV3SFCA) method as a new approach. The MHV3SFCA method integrates the strengths of several existing FCA methods into a single method, such as supply competition through the Huff model, and the integration of variable effective catchment sizes. In addition, and as a novelty, the MHV3SFCA relies on the assumption of a constant overall population demand, independent of the distances between population units and supply sites. It also accounts for absolute difference in distances without overestimating distance effects. Based on the results of a simulation study the paper discusses the strengths of the MHV3SFCA method capturing spatial differences in access to health care services.

A Three-Phase CDRT Strategy Based on Successive Relay for Smart Grid

In the vision of the future smart grid, the communication is often featured by wide range, massive connect, and low latency, which poses new requirements on the reachable distance and spectral efficiency of wireless communication. In this regard, this paper studies ergodic capacity enhancement by applying successive relay (SR) technology to a non-orthogonal multiple access (NOMA) based Coordinated Direct and Relay transmission (CDRT) system, where a base station (BS) communicates with a near user (NU) directly while communicating with a far user (FU) with the help of a group of relays. We design a novel three-phase CDRT strategy based on SR technology to overcome the half-duplex (HD) constrain without introducing additional noise. The proposed strategy can improve the spectral efficiency while expanding the communication coverage, which to some extent improves the communication quality of the edge users of the smart grid and reduces the communication delay. To analyze the performance of the proposed three-phase CDRT strategy, an exact and closed-form expression for ergodic capacity of the NU, the FU, and the whole system is derived. Finally, the numerical and simulation results validate the analysis results and show that the proposed strategy can improve the ergodic capacity of FU without reducing the capacity scaling of NU.

Effects of guided exploration on reaching measures of auditory peripersonal space.

Despite the recognized importance of bodily movements in spatial audition, few studies have integrated action-based protocols with spatial hearing in the peripersonal space. Recent work shows that tactile feedback and active exploration allow participants to improve performance in auditory distance perception tasks. However, the role of the different aspects involved in the learning phase, such as voluntary control of movement, proprioceptive cues, and the possibility of self-correcting errors, is still unclear. We study the effect of guided reaching exploration on perceptual learning of auditory distance in peripersonal space. We implemented a pretest-posttest experimental design in which blindfolded participants must reach for a sound source located in this region. They were divided into three groups that were differentiated by the intermediate training phase: Guided, an experimenter guides the participant's arm to contact the sound source; Active, the participant freely explores the space until contacting the source; and Control, without tactile feedback. The effects of exploration feedback on auditory distance perception in the peripersonal space are heterogeneous. Both the Guided and Active groups change their performance. However, participants in the Guided group tended to overestimate distances more than those in the Active group. The response error of the Guided group corresponds to a generalized calibration criterion over the entire range of reachable distances. Whereas the Active group made different adjustments for proximal and distal positions. The results suggest that guided exploration can induce changes on the boundary of the auditory reachable space. We postulate that aspects of agency such as initiation, control, and monitoring of movement, assume different degrees of involvement in both guided and active tasks, reinforcing a non-binary approach to the question of activity-passivity in perceptual learning and supporting a complex view of the phenomena involved in action-based learning.

Quantitative Validation and Application of the Photo-Cross-Linking Selection for Double-Stranded DNA-Encoded Libraries.

The DNA-encoded compound library (DEL) technology has accelerated the target hits discovery in new drug development. While affinity-based DEL selection can distinguish high-affinity ligands, moderate-affinity ligands are also potential drug candidates with further modifications. Herein, we designed a photo-cross-linking selection method for DELs with double-stranded DNA (dsDELs) to screen moderate-affinity ligands. We constructed two photo-cross-linking libraries with linkers of different lengths that connect a diazirine group to the DNA encoded compound. The diazirine group can be activated by UV irradiation and thus bond with the target protein in a reachable distance. In the model selection, the feasibility of the photo-cross-linking screening system was verified by qPCR and NGS technology. Both high-affinity and moderate-affinity ligands were successfully selected from the libraries.

Effect of viewing distance on object responses in macaque areas 45B, F5a and F5p

To perform tasks like grasping, the brain has to process visual object information so that the grip aperture can be adjusted before touching the object. Previous studies have demonstrated that the posterior subsector of the Anterior Intraparietal area is connected to area 45B, and its anterior counterpart to F5a. However, the role of area 45B and F5a in visually-guided grasping is poorly understood. Here, we investigated the role of area 45B, F5a and F5p in object processing during visually-guided grasping in two monkeys. We tested whether the presentation of an object in near peripersonal space activated F5p neurons more than objects with the same retinal size presented beyond reachable distance and conversely, whether neurons in 45B and F5a—which may encode a purely visual object representation—were less affected by viewing distance when equalizing retinal size. Contrary to our expectations, we found that most neurons in area 45B were object- and viewing distance-selective, and preferred mostly Near presentations. Area F5a showed much weaker object selectivity compared to 45B, with a similar preference for objects presented at the Near position. Finally, F5p neurons were less object selective and frequently Far-preferring. In sum, area 45B—but not F5p– prefers objects presented in peripersonal space.

A Simulated Policy towards Green Public Transportation in a Metropolitan in Indonesia

The need for mode of transportation is proportional with urban population growth. The dependence of people using private transportation causes many problems. In addition to congestion, it can create environmental problems such as air quality deterioration and pollution in the cities. Learning to be in this research is the process of individual learning to move from private transportation to public transportation. The purpose of this study is to predict and opportunities for private decision using the public transportation toward green transportation in Semarang city. This research is designed using a quantitative approach. Respondents in this study were workers. Data collection methods with questionnaires. The samples are collected using proportional sampling technique. Data are analyzed with binary logistic regression. The results showed that the accessibility and tariff variables are significantly influence to predict private decision for using public transportation as an effort toward green transportation. Based on the policy simulation, the opportunity of using public transportation will be higher if the distance is closer and reachable. It will be getting lower if the tariff is raised when the other variables are constant. Therefore, to influence private decisions using the public transportation, the government must be oriented towards reachable distance and tariff.

Detection of local and clustered outliers based on the density–distance decision graph

Outlier detection tasks refer to identifying the objects that have different characteristics from the normal observations. Most existing approaches detect outliers from the global perspective, which can effectively detect global outliers and most clustered outliers but cannot detect local outliers when the normal samples form clusters with different densities. The methods based on local outlier factors can effectively detect local outliers, but when the number of outliers increases, the more occurrences of clustered outliers will lead to the degeneration of the detection performance. We proposed an outlier detection method based on density–distance decision graph to detect local, global and clustered outliers simultaneously. Firstly, kernel density estimation and local reachable distance are combined to calculate the local density. The density ratio of the neighbors of an instance to itself is calculated as the degree of local outliers. Then, we propose a metric named density lifting distance as the degree of global outliers, which is calculated by the distance between k nearest neighbors with higher density of the instance and itself. The density ratio and density lift distance are combined to draw the density–distance decision graph, and the product of two metrics is calculated as the final outlier score. Comprehensive experiments were conducted on 8 synthetic datasets and 16 real-world datasets compared with 12 state-of-the-art methods. The results show that the proposed method works well when the samples form clusters with different densities as well as the percentage of outliers varies, and outperforms the state-of-the-art methods tested in terms of AUC.

Reachable Distance Function for KNN Classification

Distance function is a main metrics of measuring the affinity between two data points in machine learning. Extant distance functions often provide unreachable distance values in real applications. This can lead to incorrect measure of the affinity between data points. This paper proposes a reachable distance function for KNN classification. The reachable distance function is not a geometric direct-line distance between two data points. It gives a consideration to the class attribute of a training dataset when measuring the affinity between data points. Concretely speaking, the reachable distance between data points includes their class center distance and real distance. Its shape looks like “Z,” and we also call it a Z distance function. In this way, the affinity between data points in the same class is always stronger than that in different classes. Or, the intraclass data points are always closer than those interclass data points. We evaluated the reachable distance with experiments, and demonstrated that the proposed distance function achieved better performance in KNN classification.

Outlier detection algorithm based on k-nearest neighbors-local outlier factor

The main task of outlier detection is to detect data objects which have a different mechanism from the conventional data set. The existing outlier detection methods are mainly divided into two directions: local outliers and global outliers. Aiming at the limitations of the existing outlier detection methods, we propose a novel outlier detection algorithm which is named as kNN-LOF. First, the k-nearest neighbors algorithm is applied to divide different areas for outlier attributes, which is more suitable for outlier detection in different density distributions. Secondly, a hierarchical adjacency order is proposed to hierarchize the neighborhood range according to the link distance. The average sequence distance is calculated from the data objects in the hierarchy, and the reachable distance of an object is redefined to introduce a new local outlier factor. Experimental results show that the proposed algorithm has good performance in improving the accuracy of outlier detection.

A Novel Model for Accessibility of Bus Station and Its Application to Bottlenecks Identification: A Case Study in Harbin

Accessibility plays a crucial role in evaluating and optimizing the service quality of public transport systems. Traditionally, bus accessibility research studies mainly focus on the evaluation from the perspective of the aggregate model and analyze the service radius of the site considering the front end of travel. This paper aims to model microlevel bus accessibility calculation and accurate bottleneck station identification according to the opportunity method with AVL (Automatic Vehicle Location) data. The research featured the following control elements: (1) redefining bus accessibility with bus station as the research object; (2) running time between interstation sections is selected as the control index; (3) A new measure index of accessibility. The farthest direct reachable distance is proposed. Moreover, by introducing the quality control algorithm, the study establishes a model of upper and lower limits of accessibility based on the probability index of bilateral norms, which can be employed to identify the bottleneck stations according to the significance level. Harbin City is selected as the case study for methodology verification and shows that the accessibility method is effective and reliable. Additionally, by taking the travel demand in the region as the adjustment parameter of the quality control algorithm, the study demonstrates the ideal accessibility interval of stations and accurately locates all bottlenecks. The study presented here adds to our understanding of accessibility in the construction and management of buses and provides an essential reference for the following optimization.