Journal articles: 'Hierarchical patch dynamics'

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Fauchald, Per, and Torkild Tveraa. "Hierarchical patch dynamics and animal movement pattern." Oecologia 149, no. 3 (June 23, 2006): 383–95. http://dx.doi.org/10.1007/s00442-006-0463-7.

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Merot and Belhouchette. "Hierarchical Patch Dynamics Perspective in Farming System Design." Agronomy 9, no. 10 (October 2, 2019): 604. http://dx.doi.org/10.3390/agronomy9100604.

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Farming systems are complex and include a variety of interacting biophysical and technical components. This complexity must be taken into account when designing farming systems to improve sustainability, but more methods are needed to be able to do so. This article seeks to apply the Hierarchical Patch Dynamics theory (HPD) to farming systems to understand farming system complexity and be better able to support farming system re-design. A six-step framework is proposed to adapt the HPD theory to farming system analysis by taking into account (i) spatial and temporal interactions and (ii) field and management diversity. This framework was applied to a vineyard case study. The result was a hierarchical formalization of the farming system. The HPD framework improved understanding and enabled the formalization of (i) the hierarchical structure of the farming system, (ii) the interactions between structure and processes and (iii) scaling up and down from field to farm scale. HPD theory proved to be successful in analyzing farming system complexity at the farm scale. The framework can help with specific aspects of farming system design, such as how to change the scale of study or determining which scale should be used when choosing indicators for crop management and integrating multi-scale constraints and processes.

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Gillson, Lindsey. "Evidence of Hierarchical Patch Dynamics in an East African Savanna?" Landscape Ecology 19, no. 8 (November 2004): 883–94. http://dx.doi.org/10.1007/s10980-004-0248-5.

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Gillson, Lindsey. "Evidence of Hierarchical Patch Dynamics in an East African savanna?" Landscape Ecology 19, no. 8 (January 2005): 883–94. http://dx.doi.org/10.1007/s10980-005-0248-0.

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Afshari, Soheil, Richard Mandle, and Shu-Guang Li. "Hierarchical Patch Dynamics Modeling of Near-Well Dynamics in Complex Regional Groundwater Systems." Journal of Hydrologic Engineering 13, no. 9 (September 2008): 894–904. http://dx.doi.org/10.1061/(asce)1084-0699(2008)13:9(894).

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Peng, Shaolin, Ting Zhou, Liyin Liang, and Wentao Ren. "Landscape Pattern Dynamics and Mechanisms during Vegetation Restoration: A Multiscale, Hierarchical Patch Dynamics Approach." Restoration Ecology 20, no. 1 (October 26, 2010): 95–102. http://dx.doi.org/10.1111/j.1526-100x.2010.00741.x.

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Nagatani, Takashi, and Genki Ichinose. "Diffusively-Coupled Rock-Paper-Scissors Game with Mutation in Scale-Free Hierarchical Networks." Complexity 2020 (October 9, 2020): 1–8. http://dx.doi.org/10.1155/2020/6976328.

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We present a metapopulation dynamic model for the diffusively-coupled rock-paper-scissors (RPS) game with mutation in scale-free hierarchical networks. We investigate how the RPS game changes by mutation in scale-free networks. Only the mutation from rock to scissors (R-to-S) occurs with rate μ. In the network, a node represents a patch where the RPS game is performed. RPS individuals migrate among nodes by diffusion. The dynamics are represented by the reaction-diffusion equations with the recursion formula. We study where and how species coexist or go extinct in the scale-free network. We numerically obtained the solutions for the metapopulation dynamics and derived the transition points. The results show that, with increasing mutation rate μ, the extinction of P species occurs and then the extinction of R species occurs, and finally only S species survives. Thus, the first and second dynamical phase transitions occur in the scale-free hierarchical network. We also show that the scaling law holds for the population dynamics which suggests that the transition points approach zero in the limit of infinite size.

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Wu, Jianguo, and Orie L. Loucks. "From Balance of Nature to Hierarchical Patch Dynamics: A Paradigm Shift in Ecology." Quarterly Review of Biology 70, no. 4 (December 1995): 439–66. http://dx.doi.org/10.1086/419172.

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Kumar, Satwant, and Rufin Vogels. "Body Patches in Inferior Temporal Cortex Encode Categories with Different Temporal Dynamics." Journal of Cognitive Neuroscience 31, no. 11 (November 2019): 1699–709. http://dx.doi.org/10.1162/jocn_a_01444.

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An unresolved question in cognitive neuroscience is how representations of object categories at different levels (basic and superordinate) develop during the course of the neural response within an area. To address this, we decoded categories of different levels from the spiking responses of populations of neurons recorded in two fMRI-defined body patches in the macaque STS. Recordings of the two patches were made in the same animals with the same stimuli. Support vector machine classifiers were trained at brief response epochs and tested at the same or different epochs, thus assessing whether category representations change during the course of the response. In agreement with hierarchical processing within the body patch network, the posterior body patch mid STS body (MSB) showed an earlier onset of categorization compared with the anterior body patch anterior STS body (ASB), irrespective of the categorization level. Decoding of the superordinate body versus nonbody categories was less dynamic in MSB than in ASB, with ASB showing a biphasic temporal pattern. Decoding of the ordinate-level category human versus monkey bodies showed similar temporal patterns in both patches. The decoding onset of superordinate categorizations involving bodies was as early as for basic-level categorization, suggesting that previously reported differences between the onset of basic and superordinate categorizations may depend on the area. The qualitative difference between areas in their dynamics of category representation may hinder the interpretation of decoding dynamics based on EEG or MEG, methods that may mix signals of different areas.

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Li, Shu-Guang, Qun Liu, and Soheil Afshari. "An object-oriented hierarchical patch dynamics paradigm (HPDP) for modeling complex groundwater systems across multiple-scales." Environmental Modelling & Software 21, no. 5 (May 2006): 744–49. http://dx.doi.org/10.1016/j.envsoft.2005.11.001.

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Li, Cheng, Junxiang Li, and Jianguo Wu. "Quantifying the speed, growth modes, and landscape pattern changes of urbanization: a hierarchical patch dynamics approach." Landscape Ecology 28, no. 10 (August 21, 2013): 1875–88. http://dx.doi.org/10.1007/s10980-013-9933-6.

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Yang, Jian, Hong S. He, Brian R. Sturtevant, Brian R. Miranda, and Eric J. Gustafson. "Comparing effects of fire modeling methods on simulated fire patterns and succession: a case study in the Missouri Ozarks." Canadian Journal of Forest Research 38, no. 6 (June 2008): 1290–302. http://dx.doi.org/10.1139/x07-235.

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We compared four fire spread simulation methods (completely random, dynamic percolation, size-based minimum travel time algorithm, and duration-based minimum travel time algorithm) and two fire occurrence simulation methods (Poisson fire frequency model and hierarchical fire frequency model) using a two-way factorial design. We examined these treatment effects on simulated forest succession dynamics and fire patterns including fire frequency, size, burned area, and shape complexity of burned patches. The comparison was carried out using a forest landscape model (LANDIS) for a surface fire regime in the Missouri Ozark Highlands. Results showed that incorporation of fuel into fire occurrence modeling significantly changed simulated dynamics of fire frequency and area burned. The duration-based minimum travel time algorithm produced the highest variability in fire size, and the dynamic percolation method produced the most irregular burned patch shapes. We also found that various fire modeling methods greatly affected temporal fire patterns in the short term, but such effects were less prominent in the long term. The simulated temporal changes in landscape-level species abundances were similar for different fire modeling methods, suggesting that a complex fire modeling method may not be necessary for examining coarse-scale vegetation dynamics.

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Morse, Wayde C. "Recreation as a Social-Ecological Complex Adaptive System." Sustainability 12, no. 3 (January 21, 2020): 753. http://dx.doi.org/10.3390/su12030753.

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The environment and society are both the context for and product of human actions and interactions. Outdoor recreation is the primary interaction many people have with the environment and it is an interaction that greatly contributes to human well-being. To sustainably manage the social and ecological components of outdoor recreation, an integrative and dynamic systems perspective is needed. Analyses that link recreation management and recreational experiences to both social and ecological outcomes across multiple sales and over time are not developed. This article will outline how a number of fragmented recreation management frameworks such as the recreation experience model, beneficial outcomes, the recreation opportunity spectrum, limits of acceptable change, and constraints theory can be organized within a larger social-ecological framework. The outdoor recreation meta-framework presented here links structuration theory from the social sciences with theories of complex adaptive systems and hierarchical patch dynamics from ecology to understand the human and ecological drivers for and responses to outdoor recreation.

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DEBOUZIE, D., A. HEIZMANN, and L. HUMBLOT. "A STATISTICAL ANALYSIS OF MULTIPLE SCALES IN INSECT POPULATIONS.: A CASE STUDY: THE CHESTNUT WEEVIL CURCULIO ELEPHAS." Journal of Biological Systems 01, no. 03 (September 1993): 239–55. http://dx.doi.org/10.1142/s0218339093000161.

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Populations of the chestnut weevil (Coleoptera: Curculionidae) living in 14 patches (13 with chestnut trees, 1 with oak) were studied over a period of twelve years. Four spatial scales were considered: the patch (one or several trees), the chestnut tree (for patches with several trees), the chestnut-husk and the chestnut. Heterogeneity was the highest between trees and among chestnuts; it was larger in multiple-tree patches than in single-tree patches. The infestation rate per tree varied from 0 to 0.41 immature weevils per fruit. The distribution of immature weevils per chestnut was highly contagious. Different mechanisms are implied at the two main scales, trees and chestnuts, and must be incorporated in a hierarchical model of population dynamics. Difficulties due to the application of metapopulation concept to natural populations of insects are underlined.

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Baskent, Emin Z., and Glen A. Jordan. "Characterizing spatial structure of forest landscapes." Canadian Journal of Forest Research 25, no. 11 (November 1, 1995): 1830–49. http://dx.doi.org/10.1139/x95-198.

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Forest landscape management is based on the premise that resource flows as well as biodiversity levels and ecosystem processes are determined by the array and spatial arrangement of forest conditions, i.e., spatial structure, and its change over time. This paper points out that a quantitative basis for measuring spatial structure is a prerequisite to implementing forest landscape management. Without such, structural objectives cannot be established nor can the understanding of spatial dynamics necessary to achieve structural objectives be mastered. This paper presents a comprehensive collection of measurements, some old and some new, organized in a hierarchical framework. The framework organizes structural measurements by geographical scale, i.e., landscape and patch, and within these by areal, lineal, and topological categories. The hierarchical framework is offered as a means to simplify interpretation of a rather large and complex set of measurements. Using this framework, the paper presents more than two dozen measurements. In each case, the measurements are discussed in terms of calculation algorithm, interpretation, and timber and (or) wildlife habitat context. The potential use of the measurements for quantifying landscape structure is demonstrated with an example. The paper concludes with a general discussion of the implications of the measurements presented for forest landscape management.

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Benoit-Bird, Kelly J., and Whitlow W. L. Au. "Spatial dynamics of a nearshore, micronekton sound-scattering layer." ICES Journal of Marine Science 60, no. 4 (January 1, 2003): 899–913. http://dx.doi.org/10.1016/s1054-3139(03)00092-4.

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AbstractIn the Hawaiian Islands, there is a distinct resident community of micronekton, distributed along a narrow band where the upper underwater slopes of the islands meet the oceanic, mesopelagic environment. This mesopelagic boundary community serves as an important food resource to many animals. The goal of this work was to examine spatial heterogeneity of the Hawaiian mesopelagic boundary biomass at a range of scales, in the context of its diel vertical and horizontal migrations. A modified echosounder was used to sample the coasts of three Hawaiian Islands, permitting a range of scales from several meters to several kilometers to be assessed rapidly. The Hawaiian mesopelagic boundary community fits the hierarchical model of patch structure with patches within patches that are part of a larger-scale matrix of patches. Large differences in the overall distribution patterns of the mesopelagic boundary community exist along with a wide range of overall mesopelagic-animal densities. High animal-density locations have boundary-community layers with a large (kilometers) horizontal extent, and low animal-density locations have small (tens of meters), discrete patches. Higher animal-density locations are also more complex than low-density sites, with more levels of patchiness within the same range of spatial scales. Both time of day and distance from shore significantly affected the geometric and density characteristics as well as the distribution of aggregations within the boundary layer. Horizontal and vertical structures of the mesopelagic boundary community are also coupled. In high-density sites, there is strong vertical layering in acoustic-scattering strength while in low-density sites vertical acoustic structure is absent. The differences observed in the distribution of the mesopelagic boundary community at different levels of overall mesopelagic-animal density suggest biological forcing as the dominant mechanism. A description of heterogeneity in the mesopelagic boundary community in Hawaii is the first step in understanding its importance to both neritic and oceanic ecosystems and its potential for linking these two systems.

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Vicario, Saverio, Maria Adamo, Domingo Alcaraz-Segura, and Cristina Tarantino. "Bayesian Harmonic Modelling of Sparse and Irregular Satellite Remote Sensing Time Series of Vegetation Indexes: A Story of Clouds and Fires." Remote Sensing 12, no. 1 (December 24, 2019): 83. http://dx.doi.org/10.3390/rs12010083.

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Vegetation index time series from Landsat and Sentinel-2 have great potential for following the dynamics of ecosystems and are the key to develop essential variables in the realm of biodiversity. Unfortunately, the removal of pixels covered mainly by clouds reduces the temporal resolution, producing irregularity in time series of satellite images. We propose a Bayesian approach based on a harmonic model, fitted on an annual base. To deal with data sparsity, we introduce hierarchical prior distribution that integrate information across the years. From the model, the mean and standard deviation of yearly Ecosystem Functional Attributes (i.e., mean, standard deviation, and peak’s day) plus the inter-year standard deviation are calculated. Accuracy is evaluated with a simulation that uses real cloud patterns found in the Peneda-Gêres National Park, Portugal. Sensitivity to the model’s abrupt change is evaluated against a record of multiple forest fires in the Bosco Difesa Grande Regional Park in Italy and in comparison with the BFAST software output. We evaluated the sensitivity in dealing with mixed patch of land cover by comparing yearly statistics from Landsat at 30m resolution, with a 2m resolution land cover of Murgia Alta National Park (Italy) using FAO Land Cover Classification System 2.

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Atkins, Justine L., George L. W. Perry, and Todd E. Dennis. "Effects of mis-alignment between dispersal traits and landscape structure on dispersal success in fragmented landscapes." Royal Society Open Science 6, no. 1 (January 2019): 181702. http://dx.doi.org/10.1098/rsos.181702.

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Dispersal is fundamental to population dynamics and hence extinction risk. The dispersal success of animals depends on the biophysical structure of their environments and their biological traits; however, comparatively little is known about how evolutionary trade-offs among suites of biological traits affect dispersal potential. We developed a spatially explicit agent-based simulation model to evaluate the influence of trade-offs among a suite of biological traits on the dispersal success of vagile animals in fragmented landscapes. We specifically chose traits known to influence dispersal success: speed of movement, perceptual range, risk of predation, need to forage during dispersal, and amount of suitable habitat required for successful settlement in a patch. Using the metric of relative dispersal success rate, we assessed how the costs and benefits of evolutionary investment in these biological traits varied with landscape structure. In heterogeneous environments with low habitat availability and scattered habitat patches, individuals with more equal allocation across the trait spectrum dispersed most successfully. Our analyses suggest that the dispersal success of animals in heterogeneous environments is highly dependent on hierarchical interactions between trait trade-offs and the geometric configurations of the habitat patches in the landscapes through which they disperse. In an applied sense, our results indicate potential for ecological mis-alignment between species' evolved suites of dispersal-related traits and altered environmental conditions as a result of rapid global change. In many cases identifying the processes that shape patterns of animal dispersal, and the consequences of abiotic changes for these processes, will require consideration of complex relationships among a range of organism-specific and environmental factors.

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Yeari, Menahem, and Morris Goldsmith. "Hierarchical Navigation of Visual Attention." Experimental Psychology 62, no. 6 (November 2015): 353–70. http://dx.doi.org/10.1027/1618-3169/a000306.

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Abstract. This study explored the dynamics of attentional navigation between two hierarchically structured objects. Three experiments examined a Hierarchical Attentional Navigation (HAN) hypothesis, by which attentional navigation between two visual stimuli is constrained to follow the path linking the two stimuli in a hierarchical object-based representation. Presented with two adjacent compound-letter objects on each trial, participants successively identified the letter(s) at the specified hierarchical level (global or local) of the origin and destination object, respectively: local-local (Experiment 1), global-local (Experiment 2a), or local-global (Experiment 2b). The organizational complexity of the objects (2-level structure vs. 3-level structure) and their global size (large vs. small) were orthogonally manipulated. Results were generally consistent with the HAN hypothesis: overall response latency was positively related to the number of intervening levels of hierarchical object structure linking the two target levels. Hierarchical navigation was also suggested by the pattern of global size effects. The usefulness of the HAN framework for interpreting these and related findings in attention research is discussed.

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Kala, Rahul, Anupam Shukla, and Ritu Tiwari. "DYNAMIC ENVIRONMENT ROBOT PATH PLANNING USING HIERARCHICAL EVOLUTIONARY ALGORITHMS." Cybernetics and Systems 41, no. 6 (August 30, 2010): 435–54. http://dx.doi.org/10.1080/01969722.2010.500800.

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Xing, Weiwei, Xiang Wei, and Wei Lu. "Weighted time-based global hierarchical path planning in dynamic environment." Transactions of Tianjin University 20, no. 3 (June 2014): 223–31. http://dx.doi.org/10.1007/s12209-014-2377-5.

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Zhao, Zunjin, Bangshu Xiong, Shan Gai, and Lei Wang. "Improved Deep Multi-Patch Hierarchical Network With Nested Module for Dynamic Scene Deblurring." IEEE Access 8 (2020): 62116–26. http://dx.doi.org/10.1109/access.2020.2984002.

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Holzwarth, Frédéric, Nadja Rüger, and Christian Wirth. "Taking a closer look: disentangling effects of functional diversity on ecosystem functions with a trait-based model across hierarchy and time." Royal Society Open Science 2, no. 3 (March 2015): 140541. http://dx.doi.org/10.1098/rsos.140541.

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Biodiversity and ecosystem functioning (BEF) research has progressed from the detection of relationships to elucidating their drivers and underlying mechanisms. In this context, replacing taxonomic predictors by trait-based measures of functional composition (FC)—bridging functions of species and of ecosystems—is a widely used approach. The inherent challenge of trait-based approaches is the multi-faceted, dynamic and hierarchical nature of trait influence: (i) traits may act via different facets of their distribution in a community, (ii) their influence may change over time and (iii) traits may influence processes at different levels of the natural hierarchy of organization. Here, we made use of the forest ecosystem model ‘LPJ-GUESS’ parametrized with empirical trait data, which creates output of individual performance, community assembly, stand-level states and processes. To address the three challenges, we resolved the dynamics of the top-level ecosystem function ‘annual biomass change’ hierarchically into its various component processes (growth, leaf and root turnover, recruitment and mortality) and states (stand structures, water stress) and traced the influence of different facets of FC along this hierarchy in a path analysis. We found an independent influence of functional richness, dissimilarity and identity on ecosystem states and processes and hence biomass change. Biodiversity effects were only positive during early succession and later turned negative. Unexpectedly, resource acquisition (growth, recruitment) and conservation (mortality, turnover) played an equally important role throughout the succession. These results add to a mechanistic understanding of biodiversity effects and place a caveat on simplistic approaches omitting hierarchical levels when analysing BEF relationships. They support the view that BEF relationships experience dramatic shifts over successional time that should be acknowledged in mechanistic theories.

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Saravanan, S., A. Jayanthiladevi, and M. Geetha. "Fuzzy-Ant Colony based Routing on Road Networks." APTIKOM Journal on Computer Science and Information Technologies 1, no. 1 (March 1, 2016): 33–40. http://dx.doi.org/10.11591/aptikom.j.csit.102.

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Route selection is essential in everyday life. We have several algorithms for detecting efficient route on Large Road Networks. This paper introduces the hierarchical community, is presented. It splits large road networks into hierarchical structure. It introduces a multi parameter route selection system which employs Fuzzy Logic (FL) and ant’s behavior in nature is applied to the dynamic routing. The important rates of parameters such as path length and traffic are adjustable by the user. The purposes of the new hierarchical routing algorithm significantly reduce the search space. We develop a community-based hierarchical graph model that supports Dynamic, efficient route computation on large road networks.

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Saravanan, S., A. Jayanthiladevi, and M. Geetha. "Fuzzy-Ant Colony based Routing on Road Networks." APTIKOM Journal on Computer Science and Information Technologies 1, no. 1 (February 20, 2016): 33–40. http://dx.doi.org/10.34306/csit.v1i1.42.

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Route selection is essential in everyday life. We have several algorithms for detecting efficient route on Large Road Networks. This paper introduces the hierarchical community, is presented. It splits large road networks into hierarchical structure. It introduces a multi parameter route selection system which employs Fuzzy Logic (FL) and ant’s behavior in nature is applied to the dynamic routing. The important rates of parameters such as path length and traffic are adjustable by the user. The purposes of the new hierarchical routing algorithm significantly reduce the search space. We develop a community-based hierarchical graph model that supports Dynamic, efficient route computation on large road networks.

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Tan, Xiao Dong, Xu Wang, and Pi Wei Song. "A Algorithm of Path Planning Based on Multiple Mobile Robots." Applied Mechanics and Materials 470 (December 2013): 621–24. http://dx.doi.org/10.4028/www.scientific.net/amm.470.621.

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The environment of automated warehouse is complex. Path collision exists conflict between intelligent robot with unknown obstacles and intelligent mobile-robot, increasing the difficulty in multiple mobile robots path planning.To solve the problem, firstly working environmental model is established with traffic rules method and the grid method. Then the whole system adopts the idea of hierarchical cooperation for dynamic local and global path planning.By simulation this method is suitable for dynamic environment with known and unknown obstacles and effectively solve the problem of path planning for multiple mobile robots in automated warehouse.

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Montani, Margherita, Leandro Ronchi, Renzo Capitani, and Claudio Annicchiarico. "A Hierarchical Autonomous Driver for a Racing Car: Real-Time Planning and Tracking of the Trajectory." Energies 14, no. 19 (September 22, 2021): 6008. http://dx.doi.org/10.3390/en14196008.

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The aim of this study was to develop trajectory planning that would allow an autonomous racing car to be driven as close as possible to what a driver would do, defining the most appropriate inputs for the current scenario. The search for the optimal trajectory in terms of lap time reduction involves the modeling of all the non-linearities of the vehicle dynamics with the disadvantage of being a time-consuming problem and not being able to be implemented in real-time. However, to improve the vehicle performances, the trajectory needs to be optimized online with the knowledge of the actual vehicle dynamics and path conditions. Therefore, this study involved the development of an architecture that allows an autonomous racing car to have an optimal online trajectory planning and path tracking ensuring professional driver performances. The real-time trajectory optimization can also ensure a possible future implementation in the urban area where obstacles and dynamic scenarios could be faced. It was chosen to implement a local trajectory planning based on the Model Predictive Control(MPC) logic and solved as Linear Programming (LP) by Sequential Convex Programming (SCP). The idea was to achieve a computational cost, 0.1 s, using a point mass vehicle model constrained by experimental definition and approximation of the car’s GG-V, and developing an optimum model-based path tracking to define the driver model that allows A car to follow the trajectory defined by the planner ensuring a signal input every 0.001 s. To validate the algorithm, two types of tests were carried out: a Matlab-Simulink, Vi-Grade co-simulation test, comparing the proposed algorithm with the performance of an offline motion planning, and a real-time simulator test, comparing the proposed algorithm with the performance of a professional driver. The results obtained showed that the computational cost of the optimization algorithm developed is below the limit of 0.1 s, and the architecture showed a reduction of the lap time of about 1 s compared to the offline optimizer and reproducibility of the performance obtained by the driver.

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Shao, Jie, Hai Xia Lin, and Bin Song. "A Hierarchical Conflict Resolution Method for Multi-Robot Path Planning." Applied Mechanics and Materials 380-384 (August 2013): 1482–87. http://dx.doi.org/10.4028/www.scientific.net/amm.380-384.1482.

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Multi-robot path planning using shared resources, easily conflict, prioritisation is the shared resource conflicts to resolve an important technology. This paper presents a learning classifier based on dynamic allocation of priority methods to improve the performance of the robot team. Individual robots learn to optimize their behaviors first, and then a high-level planner robot is introduced and trained to resolve conflicts by assigning priority. The novel approach is designed for Partially Observable Markov Decision Process environments. Simulation results show that the method used to solve the conflict in multi-robot path planning is effective and improve the capacity of multi-robot path planning.

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Chen, Chin-Ling, Yu-Ting Tsai, Aniello Castiglione, and Francesco Palmieri. "Using bivariate polynomial to design a dynamic key management scheme for wireless sensor networks." Computer Science and Information Systems 10, no. 2 (2013): 589–609. http://dx.doi.org/10.2298/csis120907025c.

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Wireless sensor networks (WSN) have become increasingly popular in monitoring environments such as: disaster relief operations, seismic data collection, monitoring wildlife and military intelligence. The sensor typically consists of small, inexpensive, battery-powered sensing devices fitted with wireless transmitters, which can be spatially scattered to form an ad hoc hierarchically structured network. Recently, the global positioning system (GPS) facilities were embedded into the sensor node architecture to identify its location within the operating environment. This mechanism may be exploited to extend the WSN?s applications. To face with the security requirements and challenges in hierarchical WSNs, we propose a dynamic location-aware key management scheme based on the bivariate polynomial key predistribution, where the aggregation cluster nodes can easily find their best routing path to the base station, by containing the energy consumption, storage and computation demands in both the cluster nodes and the sensor nodes. This scheme is robust from the security point of view and able to work efficiently, despite the highly constrained nature of sensor nodes.

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Zhao, Bo Xuan, Jian Hua Liu, Ru Xin Ning, and Mi Liu. "Hierarchical Pipe System Disassembly Sequence Planning by Dynamic Self-Adaptive Tree Based Motion Planning." Applied Mechanics and Materials 300-301 (February 2013): 36–42. http://dx.doi.org/10.4028/www.scientific.net/amm.300-301.36.

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This paper represents a hierarchical pipe system disassembly method by using dynamic self-adaptive tree (DSAT) based motion planning to perform disassembly for a complex pipe system. A pipe system CAD model is prepared initially to indicate the environment of the disassembly procedure. The improved motion planning method provides basic algorithm support for indicating the feasible escape path of a single part. Our technic gradually reduces the complexity of the pipe system to generate a hierarchical structure which takes all geometric information of the system. The hierarchical structure is preserved and used for the generation of a disassembly relationship graph which indicates the feasible disassembly sequences.

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Luo, Jianwen, Yao Su, Lecheng Ruan, Ye Zhao, Donghyun Kim, Luis Sentis, and Chenglong Fu. "Robust Bipedal Locomotion Based on a Hierarchical Control Structure." Robotica 37, no. 10 (March 1, 2019): 1750–67. http://dx.doi.org/10.1017/s0263574719000237.

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SummaryTo improve biped locomotion’s robustness to internal and external disturbances, this study proposes a hierarchical structure with three control levels. At the high level, a foothold sequence is generated so that the Center of Mass (CoM) trajectory tracks a planned path. The planning procedure is simplified by selecting the midpoint between two consecutive Center of Pressure (CoP) points as the feature point. At the middle level, a novel robust hybrid controller is devised to drive perturbed system states back to the nominal trajectory within finite cycles without chattering. The novelty lies in that the hybrid controller is not subject to linear CoM dynamic constraints. The hybrid controller consists of two sub-controllers: an oscillation controller and a smoothing controller. For the oscillation controller, the desired CoM height is specified as a sine-shaped function, avoiding a new attractive limit cycle. However, this controller results in the inevitable chattering because of discontinuities. A smoothing controller provides continuous properties and thus can inhibit the chattering problem, but has a smaller region of attraction compared with the oscillation controller. A hybrid controller merges the two controllers for a smooth transition. At the low level, the desired CoM motion is defined as tasks and embedded in a whole body operational space (WBOS) controller to compute the joint torques analytically. The novelty of the low-level controller lies in that within the WBOS framework, CoM motion is not subject to fixed CoM dynamics and thus can be generalized.

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Aggarwal, Vijita, and Madhavi Kapoor. "Demystifying the role of internal dynamics in the path of innovative competitiveness: a serial mediation model of international joint ventures." Cross Cultural & Strategic Management 28, no. 4 (July 26, 2021): 839–66. http://dx.doi.org/10.1108/ccsm-02-2021-0023.

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PurposeThe study proposes and evaluates a parsimonious research framework by integrating the major strategic theories related to an international firm's internal dynamics. This research's essence lies in the proposition that organizational competencies, knowledge resources and processes, absorptive capacity and innovativeness form the underlying base for sustainable competitive advantage in this dynamic world.Design/methodology/approachA cross-sectional explanatory research design is adopted. Using the quantitative data obtained from the sample of Indian international joint ventures (IJVs), partial least squares structural equation modeling (PLS-SEM) is deployed to confirm the proposed relationships among the research constructs. Finally, qualitative interviews helped in triangulating the primary survey's results.FindingsA well-established relationship between knowledge transfer and innovation is negated by the Indian IJVs' data, which is delved deeper with cross-industry qualitative analysis. The novel hierarchical model with multiple mediations has nurtured quite exciting results for the business world with some significant theoretical and managerial implications.Research limitations/implicationsThis study has investigated the nexus between multi-dimensional organizational competencies, knowledge transfer, absorptive capacity and venture innovativeness in the context of Indian IJVs. It has emphasized the role of internal dynamics in cross-cultural joint ventures to attain sustainable competitiveness through strategic and technological efficiency.Originality/valueThe study has addressed the specific research gap of under-investigation of dynamic capabilities and sustainable competitiveness in international joint ventures. It has investigated a complex model of multiple mediations, yielding interesting quantitative results with qualitative insights; which is rare to match in literature.

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Madhurikkha, S., and R. Sabitha. "Hierarchical Honey Bee Model to Avoid Sleep Deprivation Attack in MANET." International Journal of Engineering & Technology 7, no. 3.6 (July 4, 2018): 358. http://dx.doi.org/10.14419/ijet.v7i3.6.15133.

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Ad-hoc networks are highly vulnerable to the attacks due to the dynamic nature of the network topology, lack of centralized management and cooperative algorithm. Nodes in the ad-hoc network are responsible to transmit packets to other nodes. One of many different kinds of attacks, a node may experience the exhaustion of power by consuming its batter power. Routing protocol controls the packet transmission over the network and calculates the routing path for transmission. The predefined static routed path is limited in ad-hoc network, and nodes have limited energy that is depleted due to transmission. Sleep deprivation attack constantly drops the power source on a particular node until the node gets shutdown. We have proposed an effective model named Honey-bee model to enhance Ad-hoc On-Demand Distance Vector Routing algorithm. Hierarchical clustering method is used for the formation of the cluster of nodes. Based on this approach, each node is assigned with a cluster that prevents the attack. We have simulated in ns2 tool compared results with other on-demand routing protocol such as Power Aware Routing Protocol, Dynamic Source Routing, Flow-State extensions to Dynamic Source Routing and AODV.

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Liu, Huailan, Zhiwang Chen, Jie Tang, Yuan Zhou, and Sheng Liu. "Mapping the technology evolution path: a novel model for dynamic topic detection and tracking." Scientometrics 125, no. 3 (September 14, 2020): 2043–90. http://dx.doi.org/10.1007/s11192-020-03700-5.

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AbstractIdentifying the evolution path of a research field is essential to scientific and technological innovation. There have been many attempts to identify the technology evolution path based on the topic model or social networks analysis, but many of them had deficiencies in methodology. First, many studies have only considered a single type of information (text or citation information) in scientific literature, which may lead to incomplete technology path mapping. Second, the number of topics in each period cannot be determined automatically, making dynamic topic tracking difficult. Third, data mining methods fail to be effectively combined with visual analysis, which will affect the efficiency and flexibility of mapping. In this study, we developed a method for mapping the technology evolution path using a novel non-parametric topic model, the citation involved Hierarchical Dirichlet Process (CIHDP), to achieve better topic detection and tracking of scientific literature. To better present and analyze the path, D3.js is used to visualize the splitting and fusion of the evolutionary path. We used this novel model to mapping the artificial intelligence research domain, through a successful mapping of the evolution path, the proposed method’s validity and merits are shown. After incorporating the citation information, we found that the CIHDP can be mapping a complete path evolution process and had better performance than the Hierarchical Dirichlet Process and LDA. This method can be helpful for understanding and analyzing the development of technical topics. Moreover, it can be well used to map the science or technology of the innovation ecosystem. It may also arouse the interest of technology evolution path researchers or policymakers.

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Fan, Shan Shan, Dian Ge Yang, Zhao Sheng Zhang, Ting Li, and Xiao Min Lian. "Fusion of Dynamic Traffic Information and Embedded GIS." Advanced Materials Research 433-440 (January 2012): 5654–58. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.5654.

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Dynamic traffic information is an important data for Intelligent Transportation System(ITS). Fusion of dynamic traffic information and embedded GIS is a basis for dynamic path planning and dynamic navigation. The approach proposed in this paper designed a model of dynamic traffic information and a hierarchical sub-model of road condition, and established algorithms for fusion with road network. Experiments with embedded GIS show that the models and integration algorithms are validated and effective. We believe the newly developed approach will be of great potential in ITS and future applications of dynamic traffic information.

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Bodó, Zsófia, and Béla Lantos. "Integrating Backstepping Control of Outdoor Quadrotor UAVs." Periodica Polytechnica Electrical Engineering and Computer Science 63, no. 2 (February 28, 2019): 122–32. http://dx.doi.org/10.3311/ppee.13321.

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In this paper an improved approach is presented for integrating backstepping control of outdoor quadrotor UAVs. The controller uses the approximated nonlinear dynamic model, while for simulation or test purposes the quadrotor can be modeled either with the precise or the simplified model. A hierarchical integrating backstepping control algorithm was constructed that has the capability of handling every effect in the dynamic model and in the meantime successfully ignores the realistic measurement noises. The hierarchical control structure consists of position, attitude and rotor control, extended with path design with continuous acceleration and/or continuous jerk. The state estimation is based on sensor fusion. Control parameters can be easily tuned. Adaptive laws are elaborated for mass and vertical disturbance force estimation. The tracking algorithm is able to follow the prescribed path with small error. The sensory system and the state estimation are prepared for outdoor applications. The embedded control system contains a HIL extension to test the control algorithms before the first flight under real time conditions.

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Bulusu, Srinivas, Srinivas Peeta, Hong Zheng, and Sushant Sharma. "PATH PRIORITIZATION AND OPERATIONAL CONSISTENCY FOR DYNAMIC TRAFFIC ASSIGNMENT: AN ANALYTIC HIERARCHICAL APPROACH." INTERNATIONAL JOURNAL FOR TRAFFIC AND TRANSPORT ENGINEERING 6, no. 2 (June 2016): 168–87. http://dx.doi.org/10.7708/ijtte.2016.6(2).05.

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Xue-Cheng Lai, Shuzhi Sam Ge, and A. Al Mamun. "Hierarchical Incremental Path Planning and Situation-Dependent Optimized Dynamic Motion Planning Considering Accelerations." IEEE Transactions on Systems, Man, and Cybernetics, Part B (Cybernetics) 37, no. 6 (December 2007): 1541–54. http://dx.doi.org/10.1109/tsmcb.2007.906577.

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Wellenzohn, Kevin, Michael H. Böhlen, and Sven Helmer. "Dynamic interleaving of content and structure for robust indexing of semi-structured hierarchical data." Proceedings of the VLDB Endowment 13, no. 10 (June 2020): 1641–53. http://dx.doi.org/10.14778/3401960.3401963.

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We propose a robust index for semi-structured hierarchical data that supports content-and-structure (CAS) queries specified by path and value predicates. At the heart of our approach is a novel dynamic interleaving scheme that merges the path and value dimensions of composite keys in a balanced way. We store these keys in our trie-based Robust Content-And-Structure index, which efficiently supports a wide range of CAS queries, including queries with wildcards and descendant axes. Additionally, we show important properties of our scheme, such as robustness against varying selectivities, and demonstrate improvements of up to two orders of magnitude over existing approaches in our experimental evaluation.

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Wang, Zhen, and Lin Huang. "VCHR: Virtual Cluster-Based Hybrid Routing Protocol." Key Engineering Materials 467-469 (February 2011): 2117–22. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.2117.

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There are a couple of inherent shortcomings which are hard to be overcome in single topology network; thus we propose a novel routing protocol—VCHR, i.e., Virtual Cluster-based Hybrid Routing, which employs hybrid topology, bears the stamp of flat and hierarchical routing protocol. At stage of hierarchical routing, VCHR draws on the idea of the virtual cluster; base station controls clustering process based on network coverage control criteria in centralized model, and ensuring the reliability of virtual clusters by making use of the three-way handshake mechanism. Flat routing employs shortest path routing protocol to get the optimized routing path to base station. In context of low algorithm complexity, the protocol could realize full network coverage control, effectively balance energy load among sensor nodes and quickly respond to network dynamic changes.

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Zhang, Bing, Changfu Zong, Guoying Chen, and Guiyuan Li. "An adaptive-prediction-horizon model prediction control for path tracking in a four-wheel independent control electric vehicle." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 12 (January 11, 2019): 3246–62. http://dx.doi.org/10.1177/0954407018821527.

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An adaptive-prediction-horizon model prediction control-based path tracking controller for a four-wheel independent control electric vehicle is designed. Unlike traditional model prediction control with fixed prediction horizon, this paper devotes to satisfy the varied path tracking demand by adjusting online the prediction horizon of model prediction control according to its effect on vehicle dynamic characteristics. Vehicle dynamic stability quantized with the vehicle sideslip-feature phase plane is preferentially considered in the prediction horizon adjustment. For stability during switching prediction horizon and for robustness during path tracking, the numerical problem inherent in the adaptive-prediction-horizon model prediction control is analysed and solved by introducing exponentially decreasing weight. Subsequently, the desired motion for path tracking with the four-wheel independent control electric vehicle is realized with a hierarchical control structure. Simulation results finally illustrate the effectiveness of the proposed method.

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Liang, Yixiao, Yinong Li, Ling Zheng, Yinghong Yu, and Yue Ren. "Yaw rate tracking-based path-following control for four-wheel independent driving and four-wheel independent steering autonomous vehicles considering the coordination with dynamics stability." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 235, no. 1 (July 15, 2020): 260–72. http://dx.doi.org/10.1177/0954407020938490.

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The path-following problem for four-wheel independent driving and four-wheel independent steering electric autonomous vehicles is investigated in this paper. Owing to the over-actuated characters of four-wheel independent driving and four-wheel independent steering autonomous vehicles, a novel yaw rate tracking-based path-following controller is proposed. First, according to the kinematic relationships between vehicle and the reference path, the yaw rate generator is designed by linear matrix inequality theory, with the ability to minimize the disturbances caused by vehicle side slip and varying curvature of path. Considering that the path-following objective and dynamics stability are in conflict with each other in some extreme path-following conditions, a coordinating mechanism based on yaw rate prediction is proposed to satisfy the two conflicting objectives. Then, according to the desired yaw rate and longitudinal velocity, a hierarchical structure is introduced for motion control. The upper-level controller calculates the generalized tracking forces while the allocation layer optimally distributes the generalized forces to tires considering tire vertical load and adhesive utilization. Finally, simulation results indicate that the proposed method can achieve excellent path-following performances in different driving conditions, while both path-following objective and dynamics stability can be satisfied.

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Kim, Yeong Hyeon, Dong Kyun Shin, Minhaz Uddin Ahmed, and Phill Kyu Rhee. "Hierarchical Open-Set Object Detection in Unseen Data." Symmetry 11, no. 10 (October 11, 2019): 1271. http://dx.doi.org/10.3390/sym11101271.

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In this paper, we propose an open-set object detection framework based on a dynamic hierarchical structure with incremental learning capabilities for unseen object classes. We were motivated by the observation that deep features extracted from visual objects show a strong hierarchical clustering property. The hierarchical feature model (HFM) was used to learn a new object class by using collaborative sampling (CS), and open-set-aware active semi-supervised learning (ASSL) algorithms. We divided object proposals into superclasses by using the agglomerative clustering algorithm. Data samples in each superclass node were classified into multiple augmented class nodes instead of directly associating with regular object classes. One or more augmented class nodes are related to a regular object class, and each augmented class has only one superclass. Object proposals from inexperienced data distribution are assigned to an augmented class node. Dynamic HFM nodes in the decision path are assembled to constitute an ensemble prediction, and the new augmented object is associated with a new regular object class. Our experimental results showed that the proposed method uses standard benchmark datasets such as PASCAL VOC, MS COCO, ILSVRC DET, and local datasets to perform better than state-of-the-art techniques.

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Liu, Chengliang, Caicheng Niu, and Ji Han. "Spatial Dynamics of Intercity Technology Transfer Networks in China’s Three Urban Agglomerations: A Patent Transaction Perspective." Sustainability 11, no. 6 (March 19, 2019): 1647. http://dx.doi.org/10.3390/su11061647.

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Technology transfer has become a vital pipeline for acquiring external knowledge. The purpose of this paper is to portray the spatial dynamics of intercity technology transfer networks in China’s three urban agglomerations based on patent right transaction data from 2008 to 2015. The integration of social networks and spatial visualization is used to explore spatial networks and influencing variables of the networks. The results demonstrate that Beijing, Shanghai, and Shenzhen are emerging as hubs in the three urban agglomerations. The spatial distributions of degree and weighted degree are significantly heterogeneous and hierarchical. The larger cities play the role of a knowledge and technology incubator, highly related to their economic scale, research and development (R&D) input, and innovation output. The evolution of intercity technology linkages is driven by the networking mechanisms of preferential attachment, hierarchical and contagious diffusion, path dependence, and path breaking. Moreover, we found that the geographical proximity and technology gaps are determinants of the strength of intercity technology linkages. As a result, it has been discovered that the network in the Beijing–Tianjin–Hebei agglomeration is organized in a tree network, while the Yangtze River Delta features a polycentric network and the Pearl River Delta has multi-star characteristics.

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Wang, Xin, Jianhua Zhang, and Massimo Scalia. "Parallel Motion Simulation of Large-Scale Real-Time Crowd in a Hierarchical Environmental Model." Mathematical Problems in Engineering 2012 (2012): 1–15. http://dx.doi.org/10.1155/2012/918497.

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This paper presents a parallel real-time crowd simulation method based on a hierarchical environmental model. A dynamical model of the complex environment should be constructed to simulate the state transition and propagation of individual motions. By modeling of a virtual environment where virtual crowds reside, we employ different parallel methods on a topological layer, a path layer and a perceptual layer. We propose a parallel motion path matching method based on the path layer and a parallel crowd simulation method based on the perceptual layer. The large-scale real-time crowd simulation becomes possible with these methods. Numerical experiments are carried out to demonstrate the methods and results.

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Song, Haoxuan, Jiahui Huang, Yan-Pei Cao, and Tai-Jiang Mu. "HDR-Net-Fusion: Real-time 3D dynamic scene reconstruction with a hierarchical deep reinforcement network." Computational Visual Media 7, no. 4 (August 5, 2021): 419–35. http://dx.doi.org/10.1007/s41095-021-0230-z.

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AbstractReconstructing dynamic scenes with commodity depth cameras has many applications in computer graphics, computer vision, and robotics. However, due to the presence of noise and erroneous observations from data capturing devices and the inherently ill-posed nature of non-rigid registration with insufficient information, traditional approaches often produce low-quality geometry with holes, bumps, and misalignments. We propose a novel 3D dynamic reconstruction system, named HDR-Net-Fusion, which learns to simultaneously reconstruct and refine the geometry on the fly with a sparse embedded deformation graph of surfels, using a hierarchical deep reinforcement (HDR) network. The latter comprises two parts: a global HDR-Net which rapidly detects local regions with large geometric errors, and a local HDR-Net serving as a local patch refinement operator to promptly complete and enhance such regions. Training the global HDR-Net is formulated as a novel reinforcement learning problem to implicitly learn the region selection strategy with the goal of improving the overall reconstruction quality. The applicability and efficiency of our approach are demonstrated using a large-scale dynamic reconstruction dataset. Our method can reconstruct geometry with higher quality than traditional methods.

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Arshad, Saba, Muhammad Sualeh, Dohyeong Kim, Dinh Van Nam, and Gon-Woo Kim. "Clothoid: An Integrated Hierarchical Framework for Autonomous Driving in a Dynamic Urban Environment." Sensors 20, no. 18 (September 5, 2020): 5053. http://dx.doi.org/10.3390/s20185053.

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In recent years, research and development of autonomous driving technology have gained much interest. Many autonomous driving frameworks have been developed in the past. However, building a safely operating fully functional autonomous driving framework is still a challenge. Several accidents have been occurred with autonomous vehicles, including Tesla and Volvo XC90, resulting in serious personal injuries and death. One of the major reasons is the increase in urbanization and mobility demands. The autonomous vehicle is expected to increase road safety while reducing road accidents that occur due to human errors. The accurate sensing of the environment and safe driving under various scenarios must be ensured to achieve the highest level of autonomy. This research presents Clothoid, a unified framework for fully autonomous vehicles, that integrates the modules of HD mapping, localization, environmental perception, path planning, and control while considering the safety, comfort, and scalability in the real traffic environment. The proposed framework enables obstacle avoidance, pedestrian safety, object detection, road blockage avoidance, path planning for single-lane and multi-lane routes, and safe driving of vehicles throughout the journey. The performance of each module has been validated in K-City under multiple scenarios where Clothoid has been driven safely from the starting point to the goal point. The vehicle was one of the top five to successfully finish the autonomous vehicle challenge (AVC) in the Hyundai AVC.

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Rahman, Taufiq. "Dynamic clustering of IP3 receptors by IP3." Biochemical Society Transactions 40, no. 2 (March 21, 2012): 325–30. http://dx.doi.org/10.1042/bst20110772.

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The versatility of Ca2+ as an intracellular messenger stems largely from the impressive, but complex, spatiotemporal organization of the Ca2+ signals. For example, the latter when initiated by IP3 (inositol 1,4,5-trisphosphate) in many cells manifest hierarchical recruitment of elementary Ca2+ release events (‘blips’ and then ‘puffs’) en route to global regenerative Ca2+ waves as the cellular IP3 concentration rises. The spacing of IP3Rs (IP3 receptors) and their regulation by Ca2+ are key determinants of these spatially organized Ca2+ signals, but neither is adequately understood. IP3Rs have been proposed to be pre-assembled into clusters, but their composition, geometry and whether clustering affects IP3R behaviour are unknown. Using patch-clamp recording from the outer nuclear envelope of DT40 cells expressing rat IP3R1 or IP3R3, we have recently shown that low concentrations of IP3 cause IP3Rs to aggregate rapidly and reversibly into small clusters of approximately four IP3Rs. At resting cytosolic Ca2+ concentrations, clustered IP3Rs open independently, but with lower open probability, shorter open duration and lesser IP3-sensitivity than lone IP3Rs. This inhibitory influence of clustering on IP3R is reversed when the [Ca2+]i (cytosolic free Ca2+ concentration) increases. The gating of clustered IP3Rs exposed to increased [Ca2+]i is coupled: they are more likely to open and close together, and their simultaneous openings are prolonged. Dynamic clustering of IP3Rs by IP3 thus exposes them to local Ca2+ rises and increases their propensity for a CICR (Ca2+-induced Ca2+ rise), thereby facilitating hierarchical recruitment of the elementary events that underlie all IP3-evoked Ca2+ signals.

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Wu, Shih-Lin, Jhe-yu Jhou, and Yi-Chun Lin. "A Novel Path Planning to Provide Real-Time Backup Paths for Vehicle Navigation Systems." International Journal of Grid and High Performance Computing 5, no. 3 (July 2013): 20–33. http://dx.doi.org/10.4018/jghpc.2013070103.

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The rapid progress of wireless technologies has made the information of real-time traffic available to vehicles. In this paper, the authors propose a dynamic path planning algorithm for vehicle navigation system which can adapt to changeable traffic and replan a better path with good travelling time for drivers within a reasonable computation time for large-scale road networks. Based on the hierarchical model of road networks, we use source-directed A* to save the path planning time, to create a good travelling time path, and to construct a backup path tree. When a traffic condition of a link in the driving path becomes worse, the replanning of a new partial path for a certain part of the backup path tree reflected by the link is calculated. The system has been tested on Taiwan road network. Through experiment results, the system presents a good efficiency for planning/replanning a path in terms of planning time and travelling time.

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Ye, Qing, Ruochen Wang, Chi Zhang, and Yingfeng Cai. "Research on Intelligent Vehicle Path Tracking with Subsystems Based on Multimodel Intelligent Hierarchical Control Theory." Mathematical Problems in Engineering 2021 (June 9, 2021): 1–15. http://dx.doi.org/10.1155/2021/7448517.

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In this paper, a multimodel intelligent hierarchical control (MIHC) algorithm with dual systems is proposed to reduce the performance conflict between a path-tracking motion system and its subsystems during the motion control process of an intelligent vehicle (IV). The working principle of the MIHC algorithm is briefly introduced first, and the dynamic models of IV and the subsystems are constructed. Then, correlation controller models based on MIHC are established. Lastly, the influence of the subsystems on the trajectory tracking of IV is validated through simulations and hardware-in-the-loop test with various condition forms. Results show that the control performance of the automatic steering system has a great influence on the path-tracking accuracy compared with that of the antilock braking system.

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Journal articles on the topic 'Hierarchical patch dynamics'

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