Spatial Box Research Articles

Improved LPAstar algorithm for power station cabinet wiring

Abstract Aiming at the complex constraints of cable layout in power plant cabinets and the low efficiency of manual design, an improved Lifelong Planning Astar algorithm (LPAstar) is proposed. By constructing a corner-length feature fusion model, the cable length and number of corners are constrained to reduce wiring costs and cable damage. The spatial minimum bounding box algorithm is employed to avoid cable suspension. Continuous incentive factors are introduced to improve algorithm efficiency. In post-processing, smoothing strategy and wire harness dispersion strategy are used to avoid excessive cable bending and ensure the standardization of wiring. The simulation experiment results show that compared with the traditional Astar algorithm, the routing length and number of corners are reduced by 27% and 65%, respectively. The generation efficiency is 84% and 87% higher than the Astar algorithm and the original LPAstar algorithm, respectively.

Refined Analysis of Spatial Three-Curved Steel Box Girder Bridge and Temperature Stress Prediction Based on WOA-BPNN

Bridges often improve the visual appeal of urban landscapes by incorporating curve elements to create iconic forms. However, it is noteworthy that curved bridges have unique mechanical properties under loads compared to straight bridges. This study analyzes a spatial three-curved steel box girder bridge based on an actual engineering case with a complex configuration. Initially, the finite element software Midas/Civil 2021 is utilized to establish a beam element model and a plate element model to examine the structural responses under dead loads in detail. Then, two different temperature gradient distribution models are employed for the temperature effect analysis. The backpropagation neural network (BPNN) optimized by the WOA algorithm is trained as a surrogate model for finite element models based on the results of temperature stress simulation. The results reveal that the bending–torsion coupling effect in the second span of the spatial three-curved steel box girder bridge is pronounced, with the maximum torque reaching 40% of the bending moment. The uneven distribution of cross-section stress is particularly significant at the vertices, where the shear lag coefficient exceeds 3. Under the action of temperature gradients, the bridge displays a warped stress state; the stress results obtained from the exponential model exhibit a 21% increase compared to BS-5400. Optimization of the weights by the WOA algorithm results in a significant improvement in prediction accuracy, and the convergence speed is improved by 30%. The coefficient of determination (R2) for predicting temperature stress can reach as high as 0.99.

Assessing Groundwater Quality for Sustainable Drinking and Irrigation: A GIS-Based Hydro-Chemical and Health Risk Study in Kovilpatti Taluk, Tamil Nadu

The continuous investigation of water resources is essential to assess pollution risks. This study investigated a groundwater assessment in the coastal belt of Tamil Nadu’s Kovilpatti Taluk, Thoothukudi district. Twenty-one groundwater samples were collected during the pre-monsoon and post-monsoon seasons, analyzing water quality parameters, namely pH, EC, Cl−, SO42−, Ca2+, Mg2+, HCO3−, TH, Na2+, and K+. The Water Quality Index (WQI) was computed and it is observed that 5% of pre-monsoon and 9% of post-monsoon samples were unsuitable for drinking. SAR, MHR, RSC, %Na and Kelley’s index were used to determine irrigation suitability. Pre-monsoon shows 29% (MHR) and 71% (RSC) unsuitable, and post-monsoon shows 59% (MHR) and 9% (RSC) unsuitable. Coastal activity, urbanization, and industrialization in Kovilpatti resulted in the degradation of groundwater quality. Solving this coastal issue requires sustainable wastewater treatment and strict industrial discharge guidelines. Spatial distribution plots, Box plots, Gibbs plots, Piper plots, Wilcox plots and Correlation Matrices had similar results to the computed WQI and its physical–chemical parameters. According to the human health risk assessment, the Mooppanpatti, Illuppaiurani, and Vijayapuri regions show high health risks due to the nitrate and fluoride concentration in the groundwater. Kadambu, Melparaipatti, Therkuilandhaikulam, and Vadakku Vandanam have low levels, posing a minimal health risk.

Locate Then Generate: Bridging Vision and Language with Bounding Box for Scene-Text VQA

In this paper, we propose a novel multi-modal framework for Scene Text Visual Question Answering (STVQA), which requires models to read scene text in images for question answering. Apart from text or visual objects, which could exist independently, scene text naturally links text and visual modalities together by conveying linguistic semantics while being a visual object in an image simultaneously. Different to conventional STVQA models which take the linguistic semantics and visual semantics in scene text as two separate features, in this paper, we propose a paradigm of "Locate Then Generate" (LTG), which explicitly unifies this two semantics with the spatial bounding box as a bridge connecting them. Specifically, at first, LTG locates the region in an image that may contain the answer words with an answer location module (ALM) consisting of a region proposal network and a language refinement network, both of which can transform to each other with one-to-one mapping via the scene text bounding box. Next, given the answer words selected by ALM, LTG generates a readable answer sequence with an answer generation module (AGM) based on a pre-trained language model. As a benefit of the explicit alignment of the visual and linguistic semantics, even without any scene text based pre-training tasks, LTG can boost the absolute accuracy by +6.06% and +6.92% on the TextVQA dataset and the ST-VQA dataset respectively, compared with a non-pre-training baseline. We further demonstrate that LTG effectively unifies visual and text modalities through the spatial bounding box connection, which is underappreciated in previous methods.

RTLSeg: A novel multi-component inspection network for railway track line based on instance segmentation

The condition monitoring of railway track line is one of the fundamental tasks to ensure the safety of the railway transportation system. Railway track line is mainly made up of tracks, fasteners, bolts, backing plates, and so on. Given the requirements for rapid and accurate inspection, an innovative and intelligent method for multi-component identification and common defect detection of railway track line is investigated based on instance segmentation. More specifically, a railway track line image (RTL-I) dataset is constructed and annotated manually in this paper. After that, based on the work of YOLACT and YOLACT++, combined with prior knowledge, a railway track line image segmentation model (RTLSeg for short) is proposed. Firstly, taking the characteristics of the objects in the RTL-I dataset, preset anchors are redesigned and a feature enhanced module is introduced in the prediction head to improve the detection and segmentation accuracy of the model. Secondly, to strengthen the internal information propagation within the model, PaFPN (path aggregation feature pyramid network) is applied instead of FPN in RTLSeg. Thirdly, with the help of CoordConv, Coord-Protonet is presented to add position awareness explicitly to the model for more robust and higher quality prototype masks. Finally, to further improve the model performance, the attention mechanism is explored and a novel spatial attention-guided bounding box branch is employed in the enhanced prediction head. Both quantitative and qualitative experimental results show that the proposed method is feasible in detecting and segmenting multi-component and common defects of railway track line, and outperforms the compared baseline models. In particular, RTLSeg is able to achieve 91.35 bbox mAP and 91.60 mask mAP with the customized dataset. Meanwhile, the average inference speed reaches 13.07 fps. The average detection accuracy and recall are 100% and 99.83%, respectively. Furthermore, the effectiveness of each optimized part of the proposed RTLSeg model is demonstrated by additional ablation study.

Innovative Design of Novel Main and Secondary Arch Collaborative Y-Shaped Arch Bridge and Research on Shear Lag Effect of Its Unconventional Thin-Walled Steel Box Arch Ribs

The first main and secondary collaborative Y-shaped steel box arch bridge under construction in China is a rarely seen innovative practice among bridges already built at home and abroad, which is an attractive engineering research topic in the field of advanced bridge design and construction, and the investigation of this bridge has made a groundbreaking contribution. The structure of unconventional thin-walled steel box arch ribs is very novel, abandoning the traditional two-dimensional arch rib structure form and adopting the new structural mode of single–double combination and joint working of main and secondary arches. However, for this innovative design, many technical difficulties including innovative design details, mechanical behavior of thin-walled structures and construction methods still need to be pioneeringly explored and thoroughly researched. In this paper, the innovative design concept of unconventional thin-walled arch ribs for spatial Y-shaped steel box arch bridges is described, and a comparative analysis with the corresponding conventional single arch rib structure is carried out. Due to the limitations of the common conventional arch bridge research methods, a combined global and local finite element method is used to analyze the static and dynamic properties of the structure, and the shear lag effect of the thin-walled steel box arch ribs is studied in a pioneering and exploratory approach. In addition, the stress distribution of the bifurcated section of the arch ribs and the configuration of the diaphragm are analyzed in detail to verify the reasonableness, advantage and applicability of the innovative design. The results show that the main and secondary arch collaboration Y-shaped steel box arch bridge has reasonable structure and superior mechanical properties and has a greater value for promotion The design concept and analysis method are worthy of use as a reference for the aesthetical and mechanical design of similar spatial Y-shaped arch bridges in the future.

A Query Understanding Framework for Earth Data Discovery

One longstanding complication with Earth data discovery involves understanding a user’s search intent from the input query. Most of the geospatial data portals use keyword-based match to search data. Little attention has focused on the spatial and temporal information from a query or understanding the query with ontology. No research in the geospatial domain has investigated user queries in a systematic way. Here, we propose a query understanding framework and apply it to fill the gap by better interpreting a user’s search intent for Earth data search engines and adopting knowledge that was mined from metadata and user query logs. The proposed query understanding tool contains four components: spatial and temporal parsing; concept recognition; Named Entity Recognition (NER); and, semantic query expansion. Spatial and temporal parsing detects the spatial bounding box and temporal range from a query. Concept recognition isolates clauses from free text and provides the search engine phrases instead of a list of words. Name entity recognition detects entities from the query, which inform the search engine to query the entities detected. The semantic query expansion module expands the original query by adding synonyms and acronyms to phrases in the query that was discovered from Web usage data and metadata. The four modules interact to parse a user’s query from multiple perspectives, with the goal of understanding the consumer’s quest intent for data. As a proof-of-concept, the framework is applied to oceanographic data discovery. It is demonstrated that the proposed framework accurately captures a user’s intent.

Non-stationary oscillations of a box-like structure of a building

The problem of forced oscillations of a spatial box of a building is considered in the paper; it consists of interacting beams and rectangular panels under dynamic effect set by base displacement according to a sinusoidal law. The problem is solved by the finite difference method. Numerical results of displacements, stresses in the risk areas of the building box are obtained.

Features of the Design of Steel Frame Structures in India for Seismic Areas

This article is devoted to the analysis of one of the most common structural designs of the steel frame of small spans, currently used in India in construction and reconstruction for seismic areas. This scheme constructively involves the implementation of the main bearing elements - bolts and columns - in the form of a spatial truss box section. At the same time, rather simple rolling profiles from small-sized corners are used, as well as a round steel bar. The studies performed by the authors were carried out using the finite element method based on the national design computing complex SCAD for Windows. The loads, as well as the geometrical characteristics of the profiles, were taken according to the current building standards of India. Based on the results of the analysis, a number of recommendations were formulated to improve the efficiency of the considered design scheme for seismic effects of varying intensity.

Spatial Subsidies and Mortality of an Estuarine Copepod Revealed Using a Box Model

Mortality of planktonic populations is difficult to determine because assumptions of the methods are rarely met, more so in estuaries where tidal exchange ensures violation of the assumption of a closed or spatially uniform population. Estuarine plankton populations undergo losses through movement from productive regions, creating a corresponding subsidy to regions that are less productive. We estimated mortality rates of the copepod Pseudodiaptomus forbesi in the San Francisco Estuary using a vertical-life-table approach with a Bayesian estimation method, combined with estimates of spatial subsidies and losses using a spatial box model with salinity-based boundaries. Data came from a long-term monitoring program and from three sample sets for 1991–2007 and 2010–2012. A hydrodynamic model coupled with a particle-tracking model supplied exchange rates between boxes and from each box to several sinks. In situ mortality, i.e., mortality corrected for movement, was highly variable. In situ mortality of adults was high (means by box and sampling program 0.1–0.9 day−1) and appeared invariant with salinity or year. In situ mortality of nauplii and copepodites increased from fresh (~ 0) to brackish water (means 0.4–0.8 day−1), probably because of consumption by clams and predatory copepods in brackish water. High mortality in the low-salinity box was offset by a subsidy which increased after 1993, indicating an increase in mortality. Our results emphasize the importance of mortality and spatial subsidies in structuring populations. Mortality estimates of estuarine plankton are feasible with sufficient sampling to overcome high variability, provided adjustments are made to account for movement.

Relative outflow enhancements during major geomagnetic storms – Cluster observations

Abstract. The rate of ion outflow from the polar ionosphere is known to vary by orders of magnitude, depending on the geomagnetic activity. However, the upper limit of the outflow rate during the largest geomagnetic storms is not well constrained due to poor spatial coverage during storm events. In this paper, we analyse six major geomagnetic storms between 2001 and 2004 using Cluster data. The six major storms fulfil the criteria of Dst < −100 nT or Kp > 7+. Since the shape of the magnetospheric regions (plasma mantle, lobe and inner magnetosphere) are distorted during large magnetic storms, we use both plasma beta (β) and ion characteristics to define a spatial box where the upward O+ flux scaled to an ionospheric reference altitude for the extreme event is observed. The relative enhancement of the scaled outflow in the spatial boxes as compared to the data from the full year when the storm occurred is estimated. Only O+ data were used because H+ may have a solar wind origin. The storm time data for most cases showed up as a clearly distinguishable separate peak in the distribution toward the largest fluxes observed. The relative enhancement in the outflow region during storm time is 1 to 2 orders of magnitude higher compared to less disturbed time. The largest relative scaled outflow enhancement is 83 (7 November 2004) and the highest scaled O+ outflow observed is 2 × 1014 m−2 s−1 (29 October 2003).

The External Clock and the Decay of a Two-particle System Inside a Spatial Box

The External Clock and the Decay of a Two-particle System Inside a Spatial Box

Computational Analysis of the Resistance to Mining Influences the Small Sports Hall Built On the Stiff Foundation Case

In the paper the influences of mining area deformations are analyzed, mainly curves of the area, for deformations of the steel construction of one sports hall. There is described the small sports hall which is built some year ago in one of Silesian cities on areas on which the active coal mining is being conducted. The new sports hall was not correctly protected to mining influences, in spite of applying the huge and expensive spatial foundation box and solutions adapting steel structures to the forecasted deformations of the area. Typical solution for mining protection applied straight out for redoubling damage. In this object appeared large displacements of steel construction elements, the irregular cracks of walls in highest zones and in the area of windows, as well as deformations of the floor making it difficult for the hall the normal use. In the paper is described the effect of application “theoretically correct” technical solutions, but not-correlated behind oneself in the mining prevention. The special attention is paid to applied structural solutions of the reinforced concrete foundation box, the spatial stiffness of the steel construction and improper materials used in construction of walls. This article contains results of extensive analyses of the FEM, theoretical deliberations and photographic documentation of damage for a real municipal sports hall. In the paper is given the method of repair of the hall and protection to further mining influences. It is pointed out that the adapted repair procedure could not interfere in functional and architectural advantages of the hall.

Color structure of Yang-Mills theory with static sources in a periodic box

We present an exploratory numerical study on the lattice of the color structure of the wave functionals of the SU(3) Yang-Mills theory in the presence of a $q\bar q$ static pair. In a spatial box with periodic boundary conditions we discuss the fact that all states contributing to the Feynman propagation kernel are global color singlets. We confirm this numerically by computing the correlations of gauge-fixed Polyakov lines with color-twisted boundary conditions in the time direction. The values of the lowest energies in the color singlet and octet external source sectors agree within statistical errors, confirming that both channels contribute to the lowest (global singlet) state of the Feynman kernel. We then study the case of homogeneous boundary conditions in the time direction for which the gauge-fixing is not needed. In this case the lowest energies extracted in the singlet external source sector agree with those determined with periodic boundary conditions, while in the octet sector the correlator is compatible with being null within our statistical errors. Therefore consistently only the singlet external source contribution has a non-vanishing overlap with the null-field wave functional.

Region Templates: Data Representation and Management for High-Throughput Image Analysis.

We introduce a region template abstraction and framework for the efficient storage, management and processing of common data types in analysis of large datasets of high resolution images on clusters of hybrid computing nodes. The region template abstraction provides a generic container template for common data structures, such as points, arrays, regions, and object sets, within a spatial and temporal bounding box. It allows for different data management strategies and I/O implementations, while providing a homogeneous, unified interface to applications for data storage and retrieval. A region template application is represented as a hierarchical dataflow in which each computing stage may be represented as another dataflow of finer-grain tasks. The execution of the application is coordinated by a runtime system that implements optimizations for hybrid machines, including performance-aware scheduling for maximizing the utilization of computing devices and techniques to reduce the impact of data transfers between CPUs and GPUs. An experimental evaluation on a state-of-the-art hybrid cluster using a microscopy imaging application shows that the abstraction adds negligible overhead (about 3%) and achieves good scalability and high data transfer rates. Optimizations in a high speed disk based storage implementation of the abstraction to support asynchronous data transfers and computation result in an application performance gain of about 1.13×. Finally, a processing rate of 11,730 4K×4K tiles per minute was achieved for the microscopy imaging application on a cluster with 100 nodes (300 GPUs and 1,200 CPU cores). This computation rate enables studies with very large datasets.

Vacuum structure in 3D supersymmetric gauge theories

Based on a talk given at the Pomeranchuk memorial conference at ITEP in June 2013, we review the vacuum dynamics in 3d supersymmetric Yang–Mills–Chern–Simons theories with and without extra matter multiplets. By analyzing the effective Born–Oppenheimer Hamiltonian in a small spatial box, we calculate the number of vacuum states (Witten index) and examine their structure for these theories. The results are identical to those obtained by other methods.

Oriented spatial box plot, a new pattern for points clusters

Nowadays, an abundance of sensors are used to collect very large datasets containing spatial points which can be mined and analysed to extract meaningful patterns and information. This article examines patterns which describe the dispersion of 2D data around a central tendency. Several state of the art patterns for point cluster analysis are presented and critiqued before a new pattern, the oriented spatial box plot, is defined. The oriented spatial box plot extends the classical one-dimensional box plot for summarising and visualising 2D point clusters. The pattern is suitable for detecting outliers and understanding the spatial density of point clusters.

Confinement of atoms under general boundary conditions

The energy spectrum of a nonrelativistic quantum particle and hydrogen-like atom is considered under the most general conditions of confinement in a spatial box (vacuum cavity). It is shown that the rearrangement of the lowest energy levels occurring in this case turns out to be considerably more significant when compared with the case of confinement achieved by the impenetrable potential barrier. The role in the rearrangement of this level, played by the von Neumann-Wigner level repulsion effect, is emphasized. For an atom confined in a spherical cavity of radius R, it is also shown that, when the role of the cavity boundary is played by the surface layer of nonzero depth d, the atomic ground state possesses a deep and pronounced minimum for the physically reasonable width and depth of that surface layer, in which the binding energy turns out to be an order of magnitude larger than that of the lowest 1s-level of a free atom E1s. Also, it becomes possible to achieve a mode when the binding energy of an atom is noticeably higher than E1s at R on the order of 10–100 nm.

Simulating the effects of global climate change on Atlantic croaker population dynamics in the mid-Atlantic Region

Projecting global climate change (GCC) effects on fish populations has primarily focused on temperature, while non-temperature effects are rarely simulated. In this study, we used a non-linear matrix population projection model of Atlantic croaker (Micropogonias undulatus) in the mid-Atlantic Bight to illustrate how global climate change effects, in addition to temperature, can be incorporated into population projections. The model was a multiple time step, stage-within-age matrix projection model with two nursery regions (Virginia and North Carolina estuaries) for young-of-the-year (YOY, egg to age-1) life stage development and a single ocean spatial box for adults. Late juvenile mortality was density-dependent and calibrated to generate a spawner-recruit relationship similar to observed values. Model simulations were for 160 years. Global climate change effects were estimated for 2020, 2050, and 2080, which resulted in three new sets of parameter values of the matrix model. The first 40 years of the 160 years were baseline, followed by 40 years of 2020 parameter values, 40 years of 2050 values, and 40 years of 2080 values. Changes in the parameters of the matrix model were based on changes in annual and seasonal temperatures generated by global circulation models, as well as presumed changes in precipitation causing increased hypoxia, increased variability in salinity, rising sea level, and changes in ocean circulation causing increased northward and offshore transport. Global climate change resulted in increased croaker abundance with lower inter-annual variability. Sensitivity analysis with each GCC effect imposed singly showed that the increase in croaker abundance under GCC was due to the complex suite of positive and negative responses across multiple life stages. The major positive response was due to warmer temperatures, and the major negative effects were due to increased variability in salinity, increased offshore transport, and sea level rise. A second sensitivity analysis showed that important, but highly uncertain, effects produced smoothly increasing population responses with increasing magnitude. We discuss how effects other than temperature can be important to projecting population responses to GCC, and the strengths and weaknesses of our analysis. Our analysis demonstrates how a variety of GCC-related effects can be incorporated into traditional population models; what is needed is sufficient empirical information to quantify the effects in terms of growth, mortality, movement, and reproduction.

Monte Carlo simulations of an unconventional phase transition for a two-dimensional dimerized quantum Heisenberg model

Motivated by the indication of a new critical theory for the spin-1/2 Heisenberg model with a spatially staggered anisotropy on the square lattice, we reinvestigate the phase transition of this model induced by dimerization using first-principle Monte Carlo simulations. We focus on studying the finite-size scaling of ${\ensuremath{\rho}}_{s1}2L$ and ${\ensuremath{\rho}}_{s2}2L$, where $L$ stands for the spatial box size used in the simulations and ${\ensuremath{\rho}}_{si}$, with $i\ensuremath{\in}{1,2}$, is the spin-stiffness in the $i$-direction. Remarkably, while we observe a large correction to scaling for the observable ${\ensuremath{\rho}}_{s1}2L$, the data for ${\ensuremath{\rho}}_{s2}2L$ exhibit a good scaling behavior without any indication of a large correction. As a consequence, we are able to obtain a numerical value for the critical exponent $\ensuremath{\nu}$, which is consistent with the known $O(3)$ result with moderate computational effort. Further, we additionally carry out an unconventional finite-size scaling analysis with which we assume that the ratio of the spatial winding numbers squared is fixed through all simulations. The theoretical correctness of our idea is argued and its validity is confirmed. Using this unconventional finite-size scaling method, even from ${\ensuremath{\rho}}_{s1}L$, which receives the most serious correction among the observables considered in this study, we are able to arrive at a value for $\ensuremath{\nu}$ consistent with the expected $O(3)$ value. A detailed investigation to compare these two finite-size scaling methods should be performed.