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Journal articles on the topic 'Spatial-Dynamic Optimization'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 February 2022

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Jeong, Hanbat, and Lung-fei Lee. "Spatial dynamic models with intertemporal optimization: Specification and estimation." Journal of Econometrics 218, no. 1 (2020): 82–104. http://dx.doi.org/10.1016/j.jeconom.2019.10.012.

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Zhu, Nanhai, and Jinlei Liu. "Multiobjective Topology Optimization of Spatial-Structure Joints." Advances in Civil Engineering 2021 (April 10, 2021): 1–13. http://dx.doi.org/10.1155/2021/5530644.

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To realize the static and dynamic multiobjective topology optimization of joints in spatial structures, structural topology optimization is carried out to maximize the stiffness under static multiload conditions and maximize the first third-order dynamic natural frequencies. According to the single-objective optimization results, the objective function of the multiobjective topology optimization of joints is established by using the compromise programming method, and the weight coefficient of each static load condition is determined by using the analytic hierarchy process. Subsequently, under the constraint of the volume fraction, the multiobjective topology optimization of joints is realized by minimizing the multiobjective function. Finally, the optimized structure is smoothed to obtain a smoother joint, and its mechanical properties are compared with those of the hollow ball joint. The results indicate that the multiobjective topology optimization that considers the static stiffness and dynamic frequency can effectively improve the mechanical properties of the structure. Through the research on multiobjective topology optimization, a new type of spatial joint with reasonable stress, a novel form, and aesthetic shape can be obtained, which mitigates the shortcomings of single-objective topology optimization. In comparison to hollow spherical joints with the same weight, topology-optimized joints have a superior ability to resist deformation and improve low-order frequency, which verifies the feasibility of applying multiobjective topology optimization to the lightweight design of joints.

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TORII, Takao, Kazufumi WATANABE, Bin Fen, and Nobuyoshi MORITA. "Optimization of Link Shape on Dynamic Design of Spatial RSSR Mechanism." Proceedings of the JSME annual meeting 2004.4 (2004): 167–68. http://dx.doi.org/10.1299/jsmemecjo.2004.4.0_167.

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Zhu, Yong Yong, and S. Y. Gao. "Optimization Research on Dynamic Balance of Spatial Engine under Limiting Shaking Moment." Materials Science Forum 626-627 (August 2009): 693–98. http://dx.doi.org/10.4028/www.scientific.net/msf.626-627.693.

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Dynamic balance of the spatial engine is researched. By considering the special wobble-plate engine as the model of spatial RRSSC linkages, design variables on the engine structure are confirmed based on the configuration characters and kinetic analysis of wobble-plate engine. In order to control the vibration of the engine frame and to decrease noise caused by the spatial engine, objective function is choosed as the dimensionless combinations of the various shaking forces and moments, the restriction condition of which presents limiting the percent of shaking moment. Then the optimization design is investigated by the mathematical model for dynamic balance. By use of the optimization design method to a type of wobble-plate engine, the optimization process as an example is demonstrated, it shows that the optimized design method benefits to control vibration and noise on the engines and improve the performance practically and theoretically.

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Zeng, Mingbin, Xu Yang, Mengxing Wang, and Bangjiang Xu. "Application of Angle Related Cost Function Optimization for Dynamic Path Planning Algorithm." Algorithms 11, no. 8 (2018): 127. http://dx.doi.org/10.3390/a11080127.

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In recent years, Intelligent Transportation Systems (ITS) have developed a lot. More and more sensors and communication technologies (e.g., cloud computing) are being integrated into cars, which opens up a new design space for vehicular-based applications. In this paper, we present the Spatial Optimized Dynamic Path Planning algorithm. Our contributions are, firstly, to enhance the effective of loading mechanism for road maps by dividing the connected sub-net, and building a spatial index; and secondly, to enhance the effect of the dynamic path planning by optimizing the search direction. We use the real road network and real-time traffic flow data of Karamay city to simulate the effect of our algorithm. Experiments show that our Spatial Optimized Dynamic Path Planning algorithm can significantly reduce the time complexity, and is better suited for use as a real-time navigation system. The algorithm can achieve superior real-time performance and obtain the optimal solution in dynamic path planning.

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Nurullah, A. M. M., Glen A. Jordan, and Emin Zeki Baskent. "Spatial stratification in forest modelling." Forestry Chronicle 76, no. 2 (2000): 311–17. http://dx.doi.org/10.5558/tfc76311-2.

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This paper discusses the concept of spatial stratification (SS) as applied to forest modelling in general, and spatial forest modelling in particular. SS is a way of providing a geographically explicit forest description in forest modelling, or a way of accommodating spatially explicit management objectives and interventions. In the former, called a priori SS, stands of a forest landscape are spatially aggregated into a set of stand clusters which become input to forest modelling. The latter, called dynamic SS, utilizes stands as the input forest description upon which various spatial aggregations occur throughout forest modelling. Distinctions between the two alternative approaches are highlighted and implementation considerations are examined within the forest landscape management design context. The paper concludes that: (i) modelling techniques are directly linked to forest stratification approaches; and (ii) a priori stratification is seriously limited in spatial modelling for landscape management design where multiple and often conflicting spatial objectives exist. In view of these findings, the paper outlines an alternative spatial forest modelling approach using a combination of dynamic SS and heuristic optimization. Key words: spatial stratification, spatial forest modelling, heuristic optimization, forest management

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Speir, Cameron, Jae Han, and Nicholas Brozović. "Spatial Dynamic Optimization of Groundwater Use with Ecological Standards for Instream Flow." Water Economics and Policy 02, no. 03 (2016): 1650013. http://dx.doi.org/10.1142/s2382624x16500132.

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We examine how variations in the spatial distribution and timing of groundwater management actions, as well as the physical characteristics of a stream aquifer system, affect regulators’ ability to meet instream goals in a stream-aquifer system. We propose an optimization model that distributes restrictions on groundwater pumping among a set of irrigators in a way that minimizes costs, subject to meeting instream flow requirements. Our model is distinguished by two features: (1) instream flow requirements must be met daily and (2) we incorporate a hydrologic model of stream-aquifer interaction that allows the time lags of the stream depletion impact that vary across space. Our results show that there is a tradeoff between the daily magnitude and duration of the stream-depletion effect: more distant wells have a smaller, but longer-lived, impact on streamflow. We find that there exist important cases where in drought years where wells located closer to the stream should be allocated more water than wells farther from the stream, despite having a smaller overall effect on stream depletion. Our results show the importance of considering the lag between the time at which pumping occurs and the time at which stream depletion related to that pumping occurs.

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Jeong, Hanbat, and Lung-fei Lee. "Spatial dynamic game models for coevolution of intertemporal economic decision-making and spatial networks." Journal of Economic Dynamics and Control 129 (August 2021): 104186. http://dx.doi.org/10.1016/j.jedc.2021.104186.

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Shen, Dingcai, Bei Qian, and Min Wang. "A Species Conservation-Based Particle Swarm Optimization with Local Search for Dynamic Optimization Problems." Computational Intelligence and Neuroscience 2020 (August 1, 2020): 1–10. http://dx.doi.org/10.1155/2020/2815802.

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In the optimization of problems in dynamic environments, algorithms need to not only find the global optimal solutions in a specific environment but also to continuously track the moving optimal solutions over dynamic environments. To address this requirement, a species conservation-based particle swarm optimization (PSO), combined with a spatial neighbourhood best searching technique, is proposed. This algorithm employs a species conservation technique to save the found optima distributed in the search space, and these saved optima either transferred into the new population or replaced by the better individual within a certain distance in the subsequent evolution. The particles in the population are attracted by its history best and the optimal solution nearby based on the Euclidean distance other than the index-based. An experimental study is conducted based on the moving peaks benchmark to verify the performance of the proposed algorithm in comparison with several state-of-the-art algorithms widely used in dynamic optimization problems. The experimental results show the effectiveness and efficiency of the proposed algorithm for tracking the moving optima in dynamic environments.

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Chen, Xiu Long, Shuai Shuai Jia, Chong Jie Du, and Shi Bo Shen. "Elastic Dynamics Optimization Design of Novel High-Speed Spatial Parallel Robot." Advanced Materials Research 415-417 (December 2011): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.39.

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In order to improve performance of 4-UPS-RPS high-speed spatial parallel robot, the elastic dynamics optimization design was executed. The influence law of the mass of moving platform and the diameter of driving limbs on the dynamic performance, which includes kinematics output response and maximum dynamic stress of driving limbs, were discussed. On these grounds, the mass of moving platform and the diameter of driving limbs were optimized. The simulation results show obvious improvement of the dynamics performance for 4-UPS-RPS parallel robot, therefore the theoretical basis are provided.

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T. O. Randhir, J. G. Lee, and B. Engel. "MULTIPLE CRITERIA DYNAMIC SPATIAL OPTIMIZATION TO MANAGE WATER QUALITY ON A WATERSHED SCALE." Transactions of the ASAE 43, no. 2 (2000): 291–99. http://dx.doi.org/10.13031/2013.2704.

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Warziniack, Travis, Charles Sims, and Jessica Haas. "Fire and the joint production of ecosystem services: A spatial-dynamic optimization approach." Forest Policy and Economics 107 (October 2019): 101926. http://dx.doi.org/10.1016/j.forpol.2019.05.012.

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Shi, Yan, and Zhenzhou Lu. "Dynamic reliability analysis for structure with temporal and spatial multi-parameter." Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability 233, no. 6 (2019): 1002–13. http://dx.doi.org/10.1177/1748006x19853413.

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For efficiently estimating the dynamic failure probability of the structure with random variables, stochastic processes and temporal and spatial multi-parameter, an estimation strategy is presented based on the random field transformation. The random field transformation focusing on the dynamic reliability with only one time parameter is further investigated, and it is extended to temporal and spatial multi-parameter issue, which simulates the output as multi-dimensional Gaussian random field. Also, the active learning Kriging method is used to construct the surrogate models for the mean function and auto-covariance function of performance function. After that, the temporal and spatial dynamic failure probability can be obtained by the simulation method. Although it doesn’t need to call the real performance function during the process of simulation method, it is time computationally expensive. To address this issue, the optimization algorithm procedure is established to estimate the dynamic failure probability. Several examples including an aero engine turbine disk and a cylindrical pressure vessel are introduced to illustrate the significance and effectiveness of the proposed methods for analyzing the temporal and spatial multi-parameter dynamic failure probability.

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Pascual, Adrián, Timo Pukkala, Francisco Rodríguez, and Sergio de-Miguel. "Using Spatial Optimization to Create Dynamic Harvest Blocks from LiDAR-Based Small Interpretation Units." Forests 7, no. 12 (2016): 220. http://dx.doi.org/10.3390/f7100220.

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Chalak, Morteza, Maksym Polyakov, and David J. Pannell. "Economics of Controlling Invasive Species: A Stochastic Optimization Model for a Spatial‐dynamic Process." American Journal of Agricultural Economics 99, no. 1 (2016): 123–39. http://dx.doi.org/10.1093/ajae/aaw043.

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Almonacid, Boris, Fabián Aspée, and Francisco Yimes. "Autonomous Population Regulation Using a Multi-Agent System in a Prey–Predator Model That Integrates Cellular Automata and the African Buffalo Optimization Metaheuristic." Algorithms 12, no. 3 (2019): 59. http://dx.doi.org/10.3390/a12030059.

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This research focused on the resolution of a dynamic prey–predator spatial model. This model has six life cycles and simulates a theoretical population of prey and predators. Cellular automata represent a set of prey and predators. The cellular automata move in a discrete space in a 2d lattice that has the shape of a torus. African buffaloes represent the predators, and the grasslands represent the prey in the African savanna. Each buffalo moves in the discrete space using the proper motion equation of the African buffalo optimization metaheuristic. Two types of approaches were made with five experiments each. The first approach was the development of a dynamic prey–predator spatial model using the movement of the African buffalo optimization metaheuristic. The second approach added the characteristic of regulating the population of buffaloes using autonomous multi-agents that interact with the model dynamic prey–predator spatial model. According to the obtained results, it was possible to adjust and maintain a balance of prey and predators during a determined period using multi-agents, therefore preventing predators from destroying an entire population of prey in the coexistence space.

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Wu, Honggang, Lifang Pai, and Hao Lei. "Seismic Optimization of High Cantilever Multianchor Pile Strengthening Soil Slopes against Earthquakes." Advances in Civil Engineering 2021 (January 30, 2021): 1–20. http://dx.doi.org/10.1155/2021/6637754.

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To explore the optimal seismic performance of multianchor pile, we carried out a series of shaking table tests. Based on the special form of multianchor piles’ reinforcement, we put forward the optimal design scheme of using EPS foam as damping layers and energy-dissipation springs for improving the self-coordinating devices of anchor head. By measuring acceleration and dynamic soil-pressure response under different intensities of vibration, we analyzed the correlation between acceleration caused by seismic wave action and damage characterized by time-domain and spectral characteristics of dynamic soil-pressure. We discuss in detail the relationship between frequency and specific period of dynamic soil-pressure and acceleration. We then used the SPECTR program to calculate the energy spectrum. Under the reciprocating action of seismic waves of different intensities, our slope model showed the continuous effect of spatial coupling deformation leading to regional damage and failure. Furthermore, the spatial distribution for amplitude of acceleration and dynamic soil-pressure showed the outstanding response of lateral amplitude of pile structures without optimization. The energy-spectrum distribution of acceleration seismic input was orderly, while the dynamic soil-pressure distribution of piles was disordered. Low-frequency (≤10 Hz) seismic waves have a great influence on these structures. The difference of acceleration hysteresis along the elevations was mainly caused by the propagation stage after the main earthquake. The correlation between dynamic soil-pressure and acceleration response in each group before the pile occurred in the same earthquake area was very weak, showing a low correlation. The optimization effect of optimized structures is related to the position of the shock-absorbing layer. Under high acceleration, multianchor piles easily cause bulge failures or shear failures at the positions of sliding surfaces. These results are helpful for improvements to reliably optimize designs in pile structure dynamic parameters.

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Wang, Ze, Shi Yong Ma, and Shi An. "A Dynamic Emergency Evacuation Network Optimization Problem with Crossing Elimination Strategy." Advanced Engineering Forum 5 (July 2012): 32–37. http://dx.doi.org/10.4028/www.scientific.net/aef.5.32.

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This paper presents a dynamic evacuation network optimization problem that incorporates crossing elimination strategy. Bottleneck problem at intersections during evacuation process is analyzed for the effective evacuation planning. The developed model is formulated as a system-optimum traffic assignment based on cell transmission model (CTM), which can effectively investigate the characteristics of randomness and dynamics of evacuation flow’s spatial and temporal distribution. The numerical results show that the model can provide crucial theoretical support for evacuation decision-making for traffic managers.

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Ashrafiuon, H., and N. K. Mani. "Analysis and Optimal Design of Spatial Mechanical Systems." Journal of Mechanical Design 112, no. 2 (1990): 200–207. http://dx.doi.org/10.1115/1.2912593.

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This paper presents a new approach to optimal design of large multibody spatial mechanical systems which takes advantage of both numerical analysis and symbolic computing. Identification of system topology is carried out using graph theory. The equations of motion are formulated in terms of relative joint coordinates through the use of a velocity transformation matrix. Design sensitivity analysis is carried out using the direct differentiation method applied to the relative joint coordinate formulation for spatial systems. The symbolic manipulation program MACSYMA is used to automatically generate the necessary equations for both dynamic and design sensitivity analyses for any spatial system. The symbolic equations are written as FORTRAN statements that are linked to a general purpose computer program which performs dynamic analysis, design sensitivity analysis, and optimization, using numerical techniques. Examples are presented to demonstrate reliability and efficiency of this approach.

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Kang, Hui Mei, Qing Hua He, Jian Xin Zhu, and Yi She Xu. "Dynamic Optimization of Lift-Arm Luffing Mechanism of Rotary Drilling Rig." Advanced Materials Research 156-157 (October 2010): 1256–60. http://dx.doi.org/10.4028/www.scientific.net/amr.156-157.1256.

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It is a spatial hydraulic-linkage mechanism of the lift-arm luffing mechanism of rotary drilling rig. During the operation, all of the reaction forces (torques) acting on the drill are transmitted to the swing platform by the mechanism. The design quality of the mechanism has a direct effect on the dynamic performance of the rotary drilling rig. A model based on the SWDM-22 rotary drilling rig developed by Hunan Sunward Intelligent Machinery CO., LTD was applied for the optimization study. The Lagrange equation was established on the basis of dynamic mechanics analysis of the equivalent planar hydraulic-linkage mechanism. The load of the hydraulic cylinder of lift-arm was solved and the objective function of the dynamic optimization was established. It is a relative complicated mechanism of the working device and the complete set of constraints were constituted by formulating the structural constraints, position constraints, kinematic constraints, dynamic constraints, and construction safety constraints respectively. The genetic algorithm was adopted to implement the dynamic optimization in consideration of the characteristic of the mathematical model. An optimized design was obtained and the value of the objective function was reduced by 12%. Some discussions about the influence of the evaluation of design variables on the objective function were made and some useful results were obtained.

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Shang, Zhengyang, Jinan Gu, Wei Ding, and Enock A. Duodu. "Spatial Scheduling Optimization Algorithm for Block Assembly in Shipbuilding." Mathematical Problems in Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/1923646.

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Block assembly consumes the majority of processing time and resources in shipbuilding, and the block spatial scheduling (BSS) related to block assembly has been widely studied as the key to improve shipbuilding efficiency. BSS is a complicated NP-hard problem that aims to minimize the makespan. Since each block has specific building time and space constraints, the BSS problem can be hardly found with an acceptable solution by using constant scheduling rules. Thus, in this study, we considered the BSS problem as a time-constrained 3D bin packing mathematical model and proposed an allocation algorithm, best contact algorithm (BCA), that is more suitable for dynamic processes. Then, for global optimization of the BSS problem, we regarded the starting time of each block as a variable and used the genetic algorithm (GA) to operate and optimize the block assembly sequence. Finally, we tested the BCA + GA scheduling system with real data from a shipyard and thereby determined the block scheduling status and the daily utilization rate of the work plate. Comparison shows that the proposed algorithm is able to get shorter makespan and better block scheduling effect; it realized the optimization of the block spatial scheduling dynamically.

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Lauer, Christopher J., Claire A. Montgomery, and Thomas G. Dietterich. "Managing Fragmented Fire-Threatened Landscapes with Spatial Externalities." Forest Science 66, no. 4 (2019): 443–56. http://dx.doi.org/10.1093/forsci/fxz012.

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Abstract Accounting for externalities generated by fire spread is necessary for managing fire risk on landscapes with multiple owners. In this paper, we determine the optimal management of a synthetic landscape parameterized to represent the ecological conditions of Douglas-fir (Pseudotsuga menziesii) plantations in southwest Oregon. The problem is formulated as a dynamic game, where each agent maximizes their own objective without considering the welfare of the other agents. We demonstrate a method for incorporating spatial information and externalities into a dynamic optimization process. A machine-learning technique, approximate dynamic programming, is applied to determine the optimal timing and location of fuel treatments and timber harvests for each agent. The value functions we estimate explicitly account for the spatial interactions that generate fire risk. They provide a way to model the expected benefits, costs, and externalities associated with management actions that have uncertain consequences in multiple locations. The method we demonstrate is applied to analyze the effect of landscape fragmentation on landowner welfare and ecological outcomes.

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Bauer, S., and G. Schiefer. "Planning of National Agricultural Investment Policies with a Dynamic Spatial Optimization Model - Case, Model, Experiences." IFAC Proceedings Volumes 19, no. 10 (1986): 199–203. http://dx.doi.org/10.1016/s1474-6670(17)59666-4.

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Zheng, Linjiang, Jie Yang, Li Chen, Dihua Sun, and Weining Liu. "Dynamic spatial-temporal feature optimization with ERI big data for Short-term traffic flow prediction." Neurocomputing 412 (October 2020): 339–50. http://dx.doi.org/10.1016/j.neucom.2020.05.038.

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Konoshima, Masashi, Heidi J. Albers, Claire A. Montgomery, and Jeffrey L. Arthur. "Optimal spatial patterns of fuel management and timber harvest with fire risk." Canadian Journal of Forest Research 40, no. 1 (2010): 95–108. http://dx.doi.org/10.1139/x09-176.

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The stochastic and spatial nature of fire poses challenges for the cost-efficient allocation of fuel treatment over the landscape. A model that addresses complex but important components of fuel management decisions, spatial and dynamic aspects of fire risk, and a carefully designed framework that allows us to draw general insight into the optimal spatial pattern of management are necessary to provide a basis for developing efficient fuel treatment plans. For this purpose, we combine a physical fire model and a spatial-dynamic optimization model to explore harvest and fuel treatment across a hypothetical landscape under risk of a moving fire over a range of physical and economic conditions. Our model is able to describe spatial trade-offs involved in decision process, namely trade-offs between protection of on-site values and protection against fire spread. We found that the spatial configuration of management units can lead to heterogeneity in management across seemingly homogeneous units.

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Argany, Meysam, Mir Abolfazl Mostafavi, Vahab Akbarzadeh, Christian Gagné, and Reda Yaagoubi. "Impact of the Quality of Spatial 3D City Models on Sensor Networks Placement Optimization." GEOMATICA 66, no. 4 (2012): 291–305. http://dx.doi.org/10.5623/cig2012-055.

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Sensor networks are increasingly used for tracking, monitoring, and observing spatial dynamic phenomena in the real world (e.g. urban area). In order to ensure an efficient deployment of a sensor network, several optimization algorithms have been proposed in recent years. Most of these algorithms often rely on oversimplified sensor models. In addition, they do not consider information on the terrain topography, city models, and the presence of diverse obstacles in the sensing area (e.g. buildings, trees, poles). Only some of those optimization algorithms attempt to consider the terrain information in the optimization of a sensor network deployment. However, most of these algorithms consider that the spatial models used for this purpose are perfect representations of the reality and are not sensitive to the quality of the information. However, spatial models are simplified representations of a complex reality, and hence are inherently uncertain. In this paper we will investigate the impact of the spatial data quality on the optimization of a sensor network and its spatial coverage in an urban area. For this purpose, we will investigate specific implications of spatial data quality criteria for a 3D city model that will be used in sensor network optimization algorithms. Then, we will analyze the impact of some of those criteria on the estimation of sensor network coverage.!Afterwards, a case study for sensor network deployment in an urban area will be presented. This case study will demonstrate the impact of 3D city models quality on the estimation of coverage using global and local optimization algorithms. Finally, the results obtained from this experimentation will be presented and discussed.

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Liu, Ya-Qiang, Jun-Wei Wang, and Chang-Yin Sun. "A Lyapunov-based design of dynamic feedback compensator for linear parabolic MIMO PDEs." IMA Journal of Mathematical Control and Information 37, no. 2 (2019): 455–74. http://dx.doi.org/10.1093/imamci/dnz008.

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Abstract This paper discusses dynamic feedback compensator design for a linear parabolic partial differential equation (PDE) with multiple inputs and multiple outputs. Actuating control inputs are provided by actuators distributed over partial areas (or active at specified positions) of the spatial domain, and observation outputs are taken from the non-collocated sensors distributed over partial areas of the spatial domain. An observer-based dynamic feedback compensator is constructed via the observer-based feedback control technique to exponentially stabilize the multi-input–multi-output PDE in the spatial $\mathscr{L}^2$ norm. By constructing an appropriate Lyapunov function candidate and using two variants of Poincaré–Wirtinger inequality, sufficient conditions on the existence of such observer-based dynamic feedback compensator are developed and presented in terms of linear matrix inequalities. The well posedness of the closed-loop coupled PDEs is also analyzed within the framework of $C_0$ semigroup theory. Finally, numerical simulation results are given to show the effectiveness of the proposed method.

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Xie, Chen, and Liu. "3D Tensor Based Nonlocal Low Rank Approximation in Dynamic PET Reconstruction." Sensors 19, no. 23 (2019): 5299. http://dx.doi.org/10.3390/s19235299.

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Reconstructing images from multi-view projections is a crucial task both in the computer vision community and in the medical imaging community, and dynamic positron emission tomography (PET) is no exception. Unfortunately, image quality is inevitably degraded by the limitations of photon emissions and the trade-off between temporal and spatial resolution. In this paper, we develop a novel tensor based nonlocal low-rank framework for dynamic PET reconstruction. Spatial structures are effectively enhanced not only by nonlocal and sparse features, but momentarily by tensor-formed low-rank approximations in the temporal realm. Moreover, the total variation is well regularized as a complementation for denoising. These regularizations are efficiently combined into a Poisson PET model and jointly solved by distributed optimization. The experiments demonstrated in this paper validate the excellent performance of the proposed method in dynamic PET.

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Yang, Jiudong, Fenghua Wu, Erlong Lai, Mingyue Liu, Bo Liu, and Yingchao Zhao. "Analysis of Visualization Technology of 3D Spatial Geographic Information System." Mobile Information Systems 2021 (May 29, 2021): 1–9. http://dx.doi.org/10.1155/2021/9173281.

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Traditional urban planning is generally expressed in a two-dimensional geographic information system, but its performance is limited to the plane direction. It cannot give people more natural feelings and visionary experiences. The rapid development of three-dimensional geographic information systems brings people geographic information. The three-dimensional intuitive experience, but the traditional three-dimensional geographic information system has the disadvantages that the spatial properties are incompatible, the image rendering speed is slow, and the visualization effect is poor. In this paper, the traditional domain-oriented processing method is improved in spatial data processing and modeling. An optimized object-oriented optimization algorithm is proposed. The three-dimensional geographic information is optimized based on a dynamic multiresolution model and multilevel detail processing technology. The rendering of the system enhances the visualization. Based on the optimization algorithm of data processing and visualization technology proposed in this paper, the spatial data processing platform GISdata of 3D GIS is designed in this paper. At the same time, the 3D GIS is visualized based on OpenGL visualization software. It is shown that the optimization algorithm proposed in this paper has excellent preexperimental effects.

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Bao, Yan, Cheng Huang, Dai Zhou, and Yao-Jun Zhao. "Semi-Active Direct Velocity Control Method of Dynamic Response of Spatial Reticulated Structures Based on MR Dampers." Advances in Structural Engineering 12, no. 4 (2009): 547–58. http://dx.doi.org/10.1260/136943309789508465.

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In this paper, a semi-active optimal control strategy for spatial reticulated structures (SRS) with MR dampers subjected to dynamic actions was proposed. The motion equation of SRS embedded with MR dampers was set up. The performance function of the optimal control strategy including both the structural responses and the control efforts was constituted for the optimization of feedback gain and MR damper placement in SRS, and an integrated method of genetic-gradient based algorithm was developed to solve this optimization problem. The clipped-optimal semi-active control strategy in the conjunction of velocity output feedback was applied to compute the desired control force from the MR dampers. Finally, a numerical example of SRS dealing with optimal placement of MR dampers and feedback gains of control system demonstrates the validity of the present semi-active optimal control strategy.

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Syahiya, Minnaty, Erri Noviar Megantara, and dan Teguh Husodo. "Dynamic Spatial Model of Non-Domestic Waste Transport in Strategic Areas." E3S Web of Conferences 249 (2021): 02007. http://dx.doi.org/10.1051/e3sconf/202124902007.

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The development of strategic areas that are taking place in several cities and districts in Indonesia is one of the solutions to the problem-solving approach instructed by the central government to develop the economy. However, along with the development of physical development and infrastructure in this strategic area, environmental problems began to emerge, especially solid waste. Increased community activity is one of the triggers for this increasing environmental problem. This research is a literature study that will answer the problem, what digital tools (applications / software) in a dynamic spatial model can support the final performance and what outputs can be obtained in its use. The method used is a qualitative method, research data is obtained from secondary data, several journals or articles that reveal about solid waste management. Data analysis was performed using descriptive analytical techniques. The mapping software application will simulate the determination of the location of waste collectors, visual representation of transportation routes, and optimization of transportation issues in order to provide economic and environmental benefits by reducing travel time, distance, fuel consumption, and pollutant emissions. The dynamic spatial model shows that the ArcGIS simulation results can be used as a strong basis for measuring the overall optimal route in solid waste management and dealing with dynamic changes in the future. Incorporating planning details on paper with real-world boundaries allows for realistic comparisons, for the application of sustainable environmental planning.

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Bi, Zicheng, Gregory A. Keoleian, Zhenhong Lin, et al. "Life cycle assessment and tempo-spatial optimization of deploying dynamic wireless charging technology for electric cars." Transportation Research Part C: Emerging Technologies 100 (March 2019): 53–67. http://dx.doi.org/10.1016/j.trc.2019.01.002.

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Widener, Michael J., Mark W. Horner, and Kunlei Ma. "Positioning Disaster Relief Teams Given Dynamic Service Demand: A Hybrid Agent-Based and Spatial Optimization Approach." Transactions in GIS 19, no. 2 (2014): 279–95. http://dx.doi.org/10.1111/tgis.12092.

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Tugilimana, Alexis, Rajan Filomeno Coelho, and Ashley P. Thrall. "An integrated design methodology for modular trusses including dynamic grouping, module spatial orientation, and topology optimization." Structural and Multidisciplinary Optimization 60, no. 2 (2019): 613–38. http://dx.doi.org/10.1007/s00158-019-02230-w.

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Cong, Wentao, Zoushuang Li, Kun Cao, Guang Feng, and Rong Chen. "Transient analysis and process optimization of the spatial atomic layer deposition using the dynamic mesh method." Chemical Engineering Science 217 (May 2020): 115513. http://dx.doi.org/10.1016/j.ces.2020.115513.

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Ge, Yulei, Shurong Li, Songlin Lu, Peng Chang, and Yang Lei. "Spatial-Temporal ARX Modeling and Optimization for Polymer Flooding." Mathematical Problems in Engineering 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/713091.

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A new polymer flooding model based on spatial-temporal decomposition and autoregressive model with external input (ARX) (STDARX model) is proposed. Karhunen-Loeve (K-L) decomposition is used to model the two-dimensional state parameters of reservoir (such as water saturation, pressure, and grid concentration). The polymer injection concentration and time coefficient got from the decomposition are taken as the input and output information. After being identified by least square method, the time iterative ARX models of all state variables are obtained, we build the ARX model among pressure, water saturation, grid concentration, and moisture content of production well, and identify it with recursive least-squares (RLS) method. After combining the above two models, we get the STDARX model of polymer flooding. The accuracy is proved by model with four injection wells and nine production wells through data which is obtained from mechanism model. In order to enhance the polymer flooding oil recovery when oil price is changing, iterative dynamic programming (IDP) is applied to optimize the STDARX model, to get the optimal injection of production scheme.

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Sawada, Kenji, and Seiichi Shin. "Numerical Optimization Design of Dynamic Quantizer via Matrix Uncertainty Approach." Mathematical Problems in Engineering 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/250683.

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In networked control systems, continuous-valued signals are compressed to discrete-valued signals via quantizers and then transmitted/received through communication channels. Such quantization often degrades the control performance; a quantizer must be designed that minimizes the output difference between before and after the quantizer is inserted. In terms of the broadbandization and the robustness of the networked control systems, we consider the continuous-time quantizer design problem. In particular, this paper describes a numerical optimization method for a continuous-time dynamic quantizer considering the switching speed. Using a matrix uncertainty approach of sampled-data control, we clarify that both the temporal and spatial resolution constraints can be considered in analysis and synthesis, simultaneously. Finally, for the slow switching, we compare the proposed and the existing methods through numerical examples. From the examples, a new insight is presented for the two-step design of the existing continuous-time optimal quantizer.

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Wang, Qing Gang. "Research on Dynamic Parking Space Allocation Model in Closed Parking Lot." Applied Mechanics and Materials 734 (February 2015): 435–39. http://dx.doi.org/10.4028/www.scientific.net/amm.734.435.

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This paper investigated Dynamic Parking Space Allocation Model (DPSAM), which is one of functional modules of On-line Parking Space Reservation System (OPSRS). In the model, the parking spaces were regarded as a two-dimensional parking resource pool of temporal and spatial components. An integer programming formulation was presented with the objective function of minimizing the discontinuous parking resources. The experiment was executed to compare the allocation solutions of optimization model and random allocation with the indicators of parking resource vacancy rate, parking resource sunk rate and parking demand satisfaction rate. The result shows that optimization model can improve the utilization efficiency of parking lot and is valuable for the application of OPSRS.

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Chen, Junbo, Shouyin Liu, and Min Huang. "Low-Rank and Sparse Decomposition Model for Accelerating Dynamic MRI Reconstruction." Journal of Healthcare Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/9856058.

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The reconstruction of dynamic magnetic resonance imaging (dMRI) from partially sampled k-space data has to deal with a trade-off between the spatial resolution and temporal resolution. In this paper, a low-rank and sparse decomposition model is introduced to resolve this issue, which is formulated as an inverse problem regularized by robust principal component analysis (RPCA). The inverse problem can be solved by convex optimization method. We propose a scalable and fast algorithm based on the inexact augmented Lagrange multipliers (IALM) to carry out the convex optimization. The experimental results demonstrate that our proposed algorithm can achieve superior reconstruction quality and faster reconstruction speed in cardiac cine image compared to existing state-of-art reconstruction methods.

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Lei, Jing, and Shi Liu. "Image Reconstruction Method with the Exploitation of the Spatial Correlation for Electrical Capacitance Tomography." Measurement Science Review 15, no. 6 (2015): 284–93. http://dx.doi.org/10.1515/msr-2015-0039.

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Abstract Electrical capacitance tomography (ECT) is considered to be a competitive measurement method. The imaging objects in ECT measurements are often in a time-varying process, and exploiting the prior information related to the dynamic nature is important for reconstructing high-quality images. Different from existing reconstruction models, in this paper a new model that incorporates the spatial correlation of the pixels by introducing the radial basis function (RBF) method, the dynamic behaviors of a timevarying imaging object, and the ECT measurement information is proposed to formulate the dynamic imaging problem. An objective functional that exploits the spatial correlation of the pixels, the combinational regularizer of the first-order total variation (FOTV) and the second-order total variation (SOTV), the multi-scale regularization, the spatial constraint, and the temporal correlation is proposed to convert the ECT imaging task into an optimization problem. A split Bregman iteration (SBI) method based iteration scheme is developed for solving the proposed objective functional. Numerical simulation results validate the superiority of the proposed reconstruction method on the improvement of the imaging quality.

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Vaseghi, Forough, Mohammad Ahmadi, Mohammad Sharifi, and Mario Vanhoucke. "Generalized Multi-Scale Stochastic Reservoir Opportunity Index for enhanced well placement optimization under uncertainty in green and brownfields." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 76 (2021): 41. http://dx.doi.org/10.2516/ogst/2021014.

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Well placement planning is one of the challenging issues in any field development plan. Reservoir engineers always confront the problem that which point of the field should be drilled to achieve the highest recovery factor and/or maximum sweep efficiency. In this paper, we use Reservoir Opportunity Index (ROI) as a spatial measure of productivity potential for greenfields, which hybridizes the reservoir static properties, and for brownfields, ROI is replaced by Dynamic Measure (DM), which takes into account the current dynamic properties in addition to static properties. The purpose of using these criteria is to diminish the search region of optimization algorithms and as a consequence, reduce the computational time and cost of optimization, which are the main challenges in well placement optimization problems. However, considering the significant subsurface uncertainty, a probabilistic definition of ROI (SROI) or DM (SDM) is needed, since there exists an infinite number of possible distribution maps of static and/or dynamic properties. To build SROI or SDM maps, the k-means clustering technique is used to extract a limited number of characteristic realizations that can reasonably span the uncertainties. In addition, to determine the optimum number of clustered realizations, Higher-Order Singular Value Decomposition (HOSVD) method is applied which can also compress the data for large models in a lower-dimensional space. Additionally, we introduce the multiscale spatial density of ROI or DM (D2ROI and D2DM), which can distinguish between regions of high SROI (or SDM) in arbitrary neighborhood windows from the local SROI (or SDM) maxima with low values in the vicinity. Generally, we develop and implement a new systematic approach for well placement optimization for both green and brownfields on a synthetic reservoir model. This approach relies on the utilization of multi-scale maps of SROI and SDM to improve the initial guess for optimization algorithm. Narrowing down the search region for optimization algorithm can substantially speed up the convergence and hence the computational cost would be reduced by a factor of 4.

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Du, W., H. Fan, J. Li, and H. Wang. "Model-driven geospatial web service composition." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-6 (April 23, 2014): 7–11. http://dx.doi.org/10.5194/isprsarchives-xl-6-7-2014.

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A lot of work has been done on the geospatial service composition to support advanced processing, spatial calculation, and invoking of heterogeneous data. However, the quality of service chain is rarely considered and the process model cannot be reused. A modeldriven way of geospatial web service composition is proposed in this work, the service composition is treated as an optimization problem by <i>GwcsFlow</i> model and dynamic binding mechanism. The case of facility location analysis is provided to demonstrate the improvements in geospatial service composition through optimization algorithms.

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Moita, P. P., J. B. Cardoso, and A. J. Valido. "A Space-Time Finite Element Model for Design and Control Optimization of Nonlinear Dynamic Response." Shock and Vibration 15, no. 3-4 (2008): 307–14. http://dx.doi.org/10.1155/2008/721760.

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A design and control sensitivity analysis and multicriteria optimization formulation is derived for flexible mechanical systems. This formulation is implemented in an optimum design code and it is applied to the nonlinear dynamic response. By extending the spatial domain to the space-time domain and treating the design variables as control variables that do not change with time, the design space is included in the control space. Thus, one can unify in one single formulation the problems of optimum design and optimal control. Structural dimensions as well as lumped damping and stiffness parameters plus control driven forces, are considered as decision variables. The dynamic response and its sensitivity with respect to the design and control variables are discretized via space-time finite elements, and are integrated at-once, as it is traditionally used for static response. The adjoint system approach is used to determine the design sensitivities. Design optimization numerical examples are performed. Nonlinear programming and optimality criteria may be used for the optimization process. A normalized weighted bound formulation is used to handle multicriteria problems.

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Büyüktahtakin, İ. Esra, Zhuo Feng, Aaryn D. Olsson, George Frisvold, and Ferenc Szidarovszky. "Invasive Species Control Optimization as a Dynamic Spatial Process: An Application to Buffelgrass (Pennisetum ciliare) in Arizona." Invasive Plant Science and Management 7, no. 1 (2014): 132–46. http://dx.doi.org/10.1614/ipsm-d-13-00057.1.

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AbstractBuffelgrass (Pennisetum ciliare) is a fire-prone, African bunchgrass spreading rapidly across the southern Arizona desert. This article introduces a model that simulates buffelgrass spread over a gridded landscape over time to evaluate strategies to control this invasive species. Weed-carrying capacity, treatment costs, and damages vary across grid cells. Damage from buffelgrass depends on its density and proximity to valued resources. Damages include negative effects on native species (through spatial competition) and increased fire risk to land and buildings. We evaluate recommended “rule of thumb” control strategies in terms of their ability to prevent weed establishment in newly infested areas and to reduce damage indices over time. Two such strategies—potential damage weighting and consecutive year treatment—used in combination, provided significant improvements in long-term control over no control and over a strategy of minimizing current damages in each year. Results suggest specific recommendations for deploying rapid-response teams to prevent establishment in new areas. The long-run population size and spatial distribution of buffelgrass is sensitive to the priority given to protecting different resources. Land managers with different priorities may pursue quite different control strategies, posing a challenge for coordinating control across jurisdictions.

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Wilhelmsson, Pär, Edward Sjödin, André Wästlund, Jörgen Wallerman, Tomas Lämås, and Karin Öhman. "Dynamic treatment units in forest planning using cell proximity." Canadian Journal of Forest Research 51, no. 7 (2021): 1065–71. http://dx.doi.org/10.1139/cjfr-2020-0210.

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In forest management planning, the dynamic treatment unit (DTU) approach has become an increasingly relevant alternative to the traditional planning approach using fixed stands, due to improved remote sensing techniques and optimization procedures, with the potential for the higher goal fulfillment of forest activities. For the DTU approach, the traditional concept of fixed stands is disregarded, and forest data are kept in units with a high spatial resolution. Forest operations are planned by clustering cells to form treatment units for harvest operations. This paper presents a new model with an exact optimization technique for forming DTUs in forest planning. In comparison with most previous models, this model aims for increased flexibility by modelling the spatial dimension according to cell proximity rather than immediate adjacency. The model is evaluated using a case study with harvest flow constraints for a forest estate in southern Sweden, represented by 3587 cells. The parameter settings differed between cases, resulting in varying degrees of clustered DTUs, which caused relative net present value losses of up to 4.3%. The case without clustering had the lowest net present value when considering entry costs. The solution times varied between 2.2 s and 42 min 6 s and grew rapidly with increasing problem size.

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Temnov, V. G. "Automated calculation and optimization of structures of prefabricated buildings from standard elements for static and dynamic effects." Вестник гражданских инженеров 17, no. 3 (2020): 62–71. http://dx.doi.org/10.23968/1999-5571-2020-17-3-62-71.

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The article proposes to carry out an automated calculation and optimization of spatial structures of prefabricated buildings from standard elements. Mathematical models of calculation of structural systems for load-bearing capacity are submitted. There have been worked out an algorithm of calculation of structural systems with optimal parameters of structures in CAD environment for static and dynamic effects. Technical solutions of the structural system obtained on the basis of the results of theoretical research in the process of computer-aided design are presented.

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Salmivaara, Aura, Samuli Launiainen, Jari Perttunen, et al. "Towards dynamic forest trafficability prediction using open spatial data, hydrological modelling and sensor technology." Forestry: An International Journal of Forest Research 93, no. 5 (2020): 662–74. http://dx.doi.org/10.1093/forestry/cpaa010.

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Abstract Forest harvesting operations with heavy machinery can lead to significant soil rutting. Risks of rutting depend on the soil bearing capacity which has considerable spatial and temporal variability. Trafficability prediction is required in the selection of suitable operation sites for a given time window and conditions, and for on-site route optimization during the operation. Integrative tools are necessary to plan and carry out forest operations with minimal negative ecological and economic impacts. This study demonstrates a trafficability prediction framework that utilizes a spatial hydrological model and a wide range of spatial data. Trafficability was approached by producing a rut depth prediction map at a 16 × 16 m grid resolution, based on the outputs of a general linear mixed model developed using field data from Southern Finland, modelled daily soil moisture, spatial forest inventory and topography data, along with field measured rolling resistance and information on the mass transported through the grid cells. Dynamic rut depth prediction maps were produced by accounting for changing weather conditions through hydrological modelling. We also demonstrated a generalization of the rolling resistance coefficient, measured with harvester CAN-bus channel data. Future steps towards a nationwide prediction framework based on continuous data flow, process-based modelling and machine learning are discussed.

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Luo, Linqing, Bo Li, Yifei Yu, Xiaomin Xu, Kenichi Soga, and Jize Yan. "Time and Frequency Localized Pulse Shape for Resolution Enhancement in STFT-BOTDR." Journal of Sensors 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/3204130.

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Short-Time Fourier Transform-Brillouin Optical Time-Domain Reflectometry (STFT-BOTDR) implements STFT over the full frequency spectrum to measure the distributed temperature and strain along the optic fiber, providing new research advances in dynamic distributed sensing. The spatial and frequency resolution of the dynamic sensing are limited by the Signal to Noise Ratio (SNR) and the Time-Frequency (T-F) localization of the input pulse shape.T-Flocalization is fundamentally important for the communication system, which suppresses interchannel interference (ICI) and intersymbol interference (ISI) to improve the transmission quality in multicarrier modulation (MCM). This paper demonstrates that theT-Flocalized input pulse shape can enhance the SNR and the spatial and frequency resolution in STFT-BOTDR. Simulation and experiments ofT-Flocalized different pulses shapes are conducted to compare the limitation of the system resolution. The result indicates that rectangular pulse should be selected to optimize the spatial resolution and Lorentzian pulse could be chosen to optimize the frequency resolution, while Gaussian shape pulse can be used in general applications for its balanced performance in both spatial and frequency resolution. Meanwhile,T-Flocalization is proved to be useful in the pulse shape selection for system resolution optimization.

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Burnett, James Wesley, and Xueting Zhao. "Spatially Explicit Prediction of Wholesale Electricity Prices." International Regional Science Review 40, no. 2 (2016): 99–140. http://dx.doi.org/10.1177/0160017615607055.

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Transmission constraints often limit the flow of electricity in a regional transmission network leading to strong interaction effects across different geographically distributed points within the system. In modern wholesale electricity markets, these transmission constraints lead to spatial patterns within the nodal electricity spot prices. This study exploits these spatial patterns to better predict spot prices within a wholesale electricity market. More specifically, we use the latest spatial panel data econometric models to compare within-sample and out-of-sample forecasts against nonspatial panel data models. The spatial panel data approach is explained by demonstrating a simple network optimization model. We find that a dynamic, spatial panel data model provides the best predictions within a forecasting error context. Our results may suggest that the spatial autocorrelation between node prices extends beyond the current market-defined zonal boundaries, which calls into question whether the zonal boundaries accurately reflect the congestion boundaries within the system.

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Vo-Duy, T., D. Duong-Gia, V. Ho-Huu, and T. Nguyen-Thoi. "An Effective Couple Method for Reliability-Based Multi-Objective Optimization of Truss Structures with Static and Dynamic Constraints." International Journal of Computational Methods 17, no. 06 (2019): 1950016. http://dx.doi.org/10.1142/s0219876219500166.

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This paper proposes an effective couple method for solving reliability-based multi-objective optimization problems of truss structures with static and dynamic constraints. The proposed coupling method integrates a single-loop deterministic method (SLDM) into the nondominated sorting genetic algorithm II (NSGA-II) algorithm to give the so-called SLDM-NSGA-II. Thanks to the advantage of SLDM, the probabilistic constraints are treated as approximating deterministic constraints. And therefore the reliability-based multi-objective optimization problems can be transformed into the deterministic multi-objective optimization problems of which the computational cost is reduced significantly. In these reliability-based multi-objective optimization problems, the conflicting objective functions are to minimize the weight and the displacements of the truss. The design variables are cross-section areas of the bars and contraints include static and dynamic constraints. For reliability analysis, the effect of uncertainty of parameters such as force, added mass in the nodes, material properties and cross-section areas of the bars are taken into account. The effectiveness and reliability of the proposed method are demonstrated through three benchmark-type truss structures including a 10-bar planar truss, a 72-bar spatial truss and a 200-bar planar truss. Moreover, the influence of parameters on the reliability-based Pareto optimal fronts is also carried out.

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