Layout Optimization Research Articles

Layout optimization of pore microstructure in fluid-saturated porous media using Galerkin decoupling technology and independent continuous mapping method (GDT-ICM)

A layout optimal design method combining Galerkin decoupling technology and independent continuous mapping method (GDT-ICM) is proposed to rearrange the layout of pore microstructure. Firstly, the Galerkin decoupling technology (GDT) is employed to solve the Brinkman equation for fluid flow in fluid-saturated porous media, which integrates the Stokes equation and Darcy's law. Within this framework a self-programmable element balance equation is developed. Secondly, a permeability interpolation function is defined for each element, incorporating the permeability of the fluid and pore microstructure. This function distinguishes strictly between the fluid domain and the pore domain. Pore microstructures with arbitrary shape including permeability information are established in an Euler mesh by introducing the Carman-Kozeny equation, shape functions, the Joukowski mapping and filter functions (the modified arctan mapping function and the ‘inpolygon’ function) based on the ICM method. Thirdly, a layout optimization model aiming at minimizing energy dissipation is established to accomplish the optimal distribution of pore microstructures. A sensitivity analysis is calculated with respect to design variables and the optimal model is solved by a genetic algorithm. Numerical results demonstrate that the proposed method is effective and feasible in 2D-space. The maximum velocity within the fluid field is reduced by 45%, and the issue of localized high pressure occurring around the pore is solved. This paper provides guidance for solving the Brinkman coupled equation and the layout optimization of the microstructure in porous media.

Optimization of industrial layout in airport economic zone through government-enterprise interaction

To avoid the issue of industrial layout plans in Airport Economic Zones (AEZs) being hard to implement due to mismatched the land supply and demand, it is necessary to clarify industrial layout factors that the government (land supplier) and locating enterprises (land demanders) focus on. This study constructs a AEZ's industrial layout optimization model from the government's perspective and enterprises’ locating utility. Based on the Gale-Shapley algorithm, aiming at eliminating blocking pairs, we establish government-enterprise interacting rules and coordinating mechanisms, corresponding to two types of government-enterprise interactions, namely public consultation and investment promotion joint meeting. According to government transparency and enterprise participation, the optimization model and Agent-Based Model are adopted in the combination to simulate the government-enterprise interactions in the decision-making of industrial layout in AEZ, under two interaction rules of “enterprises provide feedback in one go - the government makes revisions in one go” and “enterprises provide feedback one by one - the government makes revisions one by one”, respectively. By analyzing the changing curves of their objective functions, the equilibrium point where both parties can reach an agreement is identified, and the industrial layout scheme in AEZ is determined that will be mutually accepted. It is found that positive interaction with high government transparency and high enterprise participation will help improve the rationality of the industrial layout in AEZ, maximizing the efficiency of spatial allocation of elements and resources.

Footprint family of China's coal-based synthetic natural gas industry

China's increasing demand for natural gas and concerns related to energy security have expanded the coal-based synthetic natural gas (CBSNG) industry. The accompanying intensive environmental and economic impacts are evaluated based on static design or simulated data, but their industrialized performance at both the project-specific and national levels remains unclear. The objective of this study is to estimate an energy-water-pollutant-carbon-economic footprint family of China's CBSNG industry. To this end, a comprehensive accounting methodology for the multiple footprints of CBSNG was developed and the first-hand dynamic operation and economic data of four commercialized projects were surveyed. Accompanied by the technology learning curve, scenarios towards 2035 were designed to predict future trajectories of these footprints. The results show that the project-specific energy-water-pollutant-carbon footprints generally reduced by 10 to 30 % from 2020 to 2022, while the economic footprints increased slightly. The total energy-water-pollutant-carbon footprints, driven by scale expansion, increased by less than 10 % and the total economic footprint increased by over 30 %. They were predicted to approximately double by 2025 and increase fivefold by 2035, which suggests the deployment of green hydrogen and a circular economy, optimization of spatial layout, and fortification of separate statistics and economic policies for sustainability.

Research and Application of Drilling and Completion Technology for Cluster Wells

Abstract Huabei Oilfield has a wide range of oil and gas resources. With the pressure of environmental protection and the need for high-quality and cost-effective exploration and development, cluster drilling has also put forward higher requirements. In this oilfield, there is no effective technology in large cluster reservoir, integrated design of drilling and production, surface engineering, intensive construction, recycling of drilling fluid and so on. Taking a block in Bayan as the research focus, combined with geological characteristics, and by means of experiment and theoretical analysis, this paper focuses on the optimization of wellhead layout, trajectory optimization and drilling fluid recycling technology of cluster well, and forms the cluster well drilling and completion technology that is suitable for reservoir characteristics in the target area of Huabei Oilfield, so as to achieve the purpose of reducing cost and increasing efficiency, speeding up production and construction and expanding space.

A multi-step mixed integer programming heuristic for warehouse layout optimization

Warehouse layout optimization is critical to inventory and logistics management in organizations. In many instances, limited warehouse space is a constraint and a barrier to expanding operations and increasing demand. We present a multi-step solution using mixed integer programming to improve space utilization and increase order retrieval and fulfillment efficiency. We present a real-world case study to demonstrate the applicability and efficiency of the proposed mixed integer programming heuristics at a large distribution center.

Deep Dynamic Layout Optimization of Photogrammetry Camera Position Based on Digital Twin

Deep Dynamic Layout Optimization of Photogrammetry Camera Position Based on Digital Twin

Research on irregular sponge layout system based on heuristic algorithms

Abstract A layout optimization method that integrates No-Fit Polygons (NFP) positioning and a genetic algorithm is proposed for the two-dimensional irregular sponge packing problem. Firstly, according to the geometric characteristics of the parts, they are classified and encoded to calculate the NFP between part classes, avoiding redundant NFP calculations. Simultaneously, heuristic rules aimed at minimizing the packing height are introduced to provide a comprehensive evaluation function for part positioning strategies, thus improving packing efficiency. Secondly, in the optimization of part sorting, a genetic algorithm is introduced to optimize the sponge packing algorithm. Finally, several standard cases provided by the European Special Interest Group on Cutting and Packing (ESICUP) are used to test the proposed packing method. The results show that compared to the traditional Bottom-Left algorithm, the computational efficiency of the proposed packing method is improved by 4.20% to 22.73%.

Layout Optimization of Wave Energy Park Based on Multi-Objective Optimization Algorithm

Abstract In this paper, both semi-analytical method and numerical simulation is applied to investigate the hydrodynamic behavior of large arrays of point-absorber wave energy converters (WECs). To analyze wave interactions among multiple WECs within an array, a semi-analytical model is developed based on the potential flow theory and the matched eigen-function expansions method. The fluid domain is divided into two kinds of regions: interior regions underneath the cylinders and an exterior region surrounding all the cylinders. The matched eigenfunction expansions method is employed to solve the radiation potential problem in each domain, and the hydrodynamic coefficients and motion response of the cylinders in the array are evaluated. To validate the accuracy of the semi-analytical method, WAMIT is adopted to simulate the wave energy park numerically and compared with the results by the semi-analytical model. The hydrodynamic characteristics and power absorption performance of the WECs within the wave energy park are analyzed. The power performance of a wave energy park is studied as functions of layout geometry, incident wave direction and separation distance between WECs respectively. Finally, MOPSO based on a surrogate model is used to optimize the layout of wave energy array.

Method for robot kinematic parameters identification based on position and orientation data obtained with laser tracker.

How to quickly and accurately identify the kinematic parameter errors is an important prerequisite for robot accuracy compensation. The laser tracker is used to measure and identify the kinematic parameters of the robot. The influence of laser tracker layout in robot pose measurement is analyzed, and the evaluation function of laser tracker layout is constructed to determine the optimal layout position. Then, the mapping relationship between the position and orientation deviation of the robot end and the deviation of each kinematic parameter is established, and the kinematic parameter identification model integrating the position and orientation information is constructed. The identification model is compared to the identification model based on position information to clarify the intrinsic reason of high accuracy. Next, aiming at the problem that the genetic algorithm is easy to prematurely converge to the local optimal solution, a hybrid genetic algorithm is constructed by introducing the simplex method to determine the optimal calibration pose set of the robot. On this basis, the results of robot kinematics parameter identification based on position measurement data, pose measurement data, and optimal calibration pose set are compared and analyzed through experiments, which verifies the effectiveness of the robot kinematics parameter identification model based on pose measurement data and optimization strategy.

A novel two-stage optimal layout model of hydrogen refueling facility network based on green electricity hydrogen production: Beijing-Tianjin-Hebei region of China as case study

Green electricity hydrogen production(GEHP) is fundamental support for developing new-type power system and achieving the green and low-carbon transformation in the transportation sector. It is key issue to build a hydrogen refueling facility network(HRFN) to link hydrogen production and consumption. Firstly, the framework of HRFN is proposed including hydrogen production points(HPP), hydrogen refueling stations(HRS) and hydrogen demand points(HDP). Secondly, a two-stage model is built. In the first stage, the siting model of HRS cluster is constructed considering the service capacity, service radius, and construction, operation and penalty costs. In the second stage, the bi-objective planning model of HRFN is constructed considering network stability, hydrogen storage and transportation forms and producing total costs. Finally, the Beijing-Tianjin-Hebei region of China(BTH) is taken as case study to verify the effectiveness. Sensitivity analyses are conducted on four factors:HRSs’ service radius, service capacity, GEHP’s efficiency and HDPs’ scope. The key findings are: 1)the service radius and capacity of HRSs and HDPs’ scope all affect the layout of HRSs, with HDPs’ scope further influencing HPPs’ number; 2)the construction and operation costs are more impacted by changes in GEHP's efficiency compared to network stability;3)the network should be strengthened to cover the whole processes from hydrogen production to consumption.

Experimental research of helicopter blade load in flight based on optical sensing

Abstract The actual flight measurement of blade load is an extremely important part of the new helicopter. In order to solve the problems existing in the traditional electrical measurement method, such as weak anti-interference ability, short life, and large added mass, a flight measurement method of blade load based on optical sensing is proposed. Firstly, the strain mode distribution law is obtained by calculating the dynamic response of the real blade. The optimal layout of the optical fiber measurement points is determined. Through theoretical analysis of strain transferring and experimental verification, a highly reliable fusion scheme of blade and fiber is designed to meet the flight requirements. Based on the power line carrier technology, the optical sensing test system for helicopter flight test is developed. The flight test of blade load is completed successfully. The results of optical fiber measurement are consistent with the results of traditional electrical measurement, which indicates that the optical sensing technology has good applicability in the measurement of helicopter blade load. At the same time, it has been proved that the optical measurement system set is reliable and durable. It is of great significance for the leap from electric measurement to optical measurement.

Quickly select heliostat candidates and design pattern-free layout using geometric projection method

Central receiver system is one of the most promising solar energy harvesting technologies, which focuses sunlight onto the receiver through heliostats to generate high temperatures for thermal cycling. The optimal layout of the heliostat plays a crucial role, but the pattern-free heliostat field layout requires multiple uses of computationally intensive shadowing and blocking efficiency, which is highly time-consuming. In this work, a new geometric projection method, Projection radius method (PRM), is proposed. It includes two aspects: (i) Quickly and effectively selecting heliostat candidates with shadowing and blocking potential by the incident and reflected ray projection radius; (ii) Designing the pattern-free heliostat field layout by employing overlap radius instead of shadowing and blocking efficiency. The results indicate that, compared to traditional methods, when designing 2650 heliostats, (i) the calculation time for optical efficiency was reduced by 63%; (ii) optical efficiency increased by 1.23%, and designing a pattern-free layout took only 2.78 h. These advancements facilitate the efficient design of large-scale pattern-free heliostat field layouts.

On Using the Distributor as a Multi Degree-of-Freedom System to Mitigate the Pressure Pulsation in an Axial Turbine at Speed-No-Load

Abstract Hydraulic axial turbines are more frequently utilized for grid regulation purposes. Sometimes, they must be operated at speed-no-load (SNL) conditions, which is characterized for some machines by a varying number of large vortical flow structures extending from the vaneless space to the draft tube, introducing detrimental pressure pulsations throughout the turbine. A recent study shows that the vortices can be mitigated by individually controlling the guide vanes. Since optimization of the distributor layout is linked with a large degree-of-freedom, machine learning is deployed to assist in finding an optimal setup cost-effectively. A reduced numerical computational-fluid-dynamics (CFD) model is built and used to generate input for Gaussian process regression surrogate models by performing 2000 steady-state simulations with varying distributor layouts. The surrogate models suggest that the optimal layout is to open seven out of 20 guide vanes in succession while keeping the remaining ones closed. However, this configuration induces large radial forces on the runner, and after implementing some modifications by trial and error, detailed time-dependent CFD simulations show that placing 4 + 3 opened guide vanes on opposite sides of the runner axis is better; it reduces the pressure peaks corresponding to a two- and three-vortex configuration, and the maximal pressure pulsations by as much as 88% in the vaneless space compared to regular SNL operation. Meanwhile, the radial force on the runner is reduced by more than 83%, and pressure pulsations on the runner blades by more than 55%, compared to the surrogate models' optimal layout prediction.

Design of innovative phase-change cold storage refrigerator and simulation analysis of discharging progress

At present, the field of cold chain logistics experiences significant growth, with refrigerator playing a pivotal role in cold chain transportation. An innovative compartmentalized phase-change cold storage refrigerator has been proposed in this study, designed to address the increasing demand for efficient and energy-saving solutions in the cold chain transportation industry. A conceptual module prototype is designed and built in this study, with an analysis of the system's charging and discharging processes under varying conditions. The cold storage refrigerator exhibits favorable matching characteristics, the charging process requires approximately 270 min, and the cooling effect sustains for about 23 h. A three-dimensional simulation model of the cold storage refrigerator is developed, enabling a comprehensive evaluation of the cooling effect and further optimization of the cold storage plate layout. The results indicate that the layout of the three-sided type cold plate significantly reduces the pre-cooling time. It is determined through simulation calculations in this study that setting the loading capacity to 50 % can strike a balance between efficient cooling and transportation efficiency. Additionally, under high-temperature conditions, the cold storage refrigerator maintains a low temperature for up to 10 h at a filling rate of 50 %.

THE MODELLING OF CARGO TRANSSHIPMENT OPERATIONS USING THE BUSINESS PROCESS MODELLING TOOLS

This paperwork explores the transshipment operations at the Port of Constanta, Romania, focusing on the unloading of big bags from barges. Utilizing Business Process Management (BPM) software, the study models the transshipment process to identify optimization opportunities. The investigation reveals challenges such as coordination complexities and potential cargo damage, alongside the benefits of cost-efficiency and flexibility offered by transshipment services. Through literature review and analysis, the study emphasizes the importance of efficient business processes and the role of BPM software in enhancing operational efficiency. By employing Aura Portal Modeller for simulation, the study identifies bottlenecks and proposes optimization strategies for the transshipment process. The proposed measures include real-time cargo assessment, inventory tracking systems, equipment analysis, and storage layout optimization. This research contributes to the understanding of transshipment operations and highlights the effectiveness of BPM software in process visualization and analysis, offering insights for enhancing efficiency and mitigating delays in supply chain management.

Multi-Source Data-Driven Extraction of Urban Residential Space: A Case Study of the Guangdong–Hong Kong–Macao Greater Bay Area Urban Agglomeration

The accurate extraction of urban residential space (URS) is of great significance for recognizing the spatial structure of urban function, understanding the complex urban operating system, and scientific allocation and management of urban resources. The traditional URS identification process is generally conducted through statistical analysis or a manual field survey. Currently, there are also superpixel segmentation and wavelet transform (WT) processes to extract urban spatial information, but these methods have shortcomings in extraction efficiency and accuracy. The superpixel wavelet fusion (SWF) method proposed in this paper is a convenient method to extract URS by integrating multi-source data such as Point of Interest (POI) data, Nighttime Light (NTL) data, LandScan (LDS) data, and High-resolution Image (HRI) data. This method fully considers the distribution law of image information in HRI and imparts the spatial information of URS into the WT so as to obtain the recognition results of URS based on multi-source data fusion under the perception of spatial structure. The steps of this study are as follows: Firstly, the SLIC algorithm is used to segment HRI in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) urban agglomeration. Then, the discrete cosine wavelet transform (DCWT) is applied to POI–NTL, POI–LDS, and POI–NTL–LDS data sets, and the SWF is carried out based on different superpixel scale perspectives. Finally, the OSTU adaptive threshold algorithm is used to extract URS. The results show that the extraction accuracy of the NLT–POI data set is 81.52%, that of the LDS–POI data set is 77.70%, and that of the NLT–LDS–POI data set is 90.40%. The method proposed in this paper not only improves the accuracy of the extraction of URS, but also has good practical value for the optimal layout of residential space and regional planning of urban agglomerations.

Study on the planning and scheduling strategies of the hydrogen supply network for road transportation in deep decarbonization scenarios

As the energy decarbonization continues to advance, hydrogen is gaining momentum. With the increasing demand for hydrogen and the lack of hydrogen infrastructure, it is urgent to solve the problem of hydrogen supply network layout planning. In order to reduce redundant construction of hydrogen supply network infrastructure and increase the rationality of its layout, this paper conducts research on the optimal layout planning of hydrogen supply network infrastructure in the transportation sector. By constructing a two-stage real-time scheduling model of hydrogen supply network, the unit cost composition of hydrogen supply network is more complete and accurate, and the location, technology type and quantity of each link of hydrogen supply network are obtained. The results show that the unit cost of China's hydrogen supply network is 27.8 CNY/kg in 2035 and 19.04 CNY/kg in 2050 under the baseline scenario. Compared with the results of existing literature, the two-stage real-time scheduling model can reduce by 7 % of the hydrogen energy supply network unit cost by decreasing the transportation vehicles and the investment capacity of fixed hydrogen storage equipment. The proposed method of the hydrogen supply network planning can provide policy-makers with the selection of sustainability pathways for dynamic hydrogen infrastructure development planning.

Layout Optimization of High-Level Directional Boreholes to Prevent Downward Invasion of Carbon Dioxide from an Overlying Coal Mine Goaf

Layout Optimization of High-Level Directional Boreholes to Prevent Downward Invasion of Carbon Dioxide from an Overlying Coal Mine Goaf

Numerical investigation on behaviour of mooring line system for container ship at berth

The constant growth of the world’s maritime industry has led to the need to increase the size of ships as wellas accelerate the trend of moving ports to open sea areas and outside estuaries. Increasing the size of ships,especially container ships, has the potential to cause unsafe ship anchoring in ports. Furthermore, the mooringof ships at the harbor also lacks international guidelines on the layout of the mooring system. Meanwhile, relocating seaports outside estuaries and open seas can create conditions for high winds, high tidal fluctuationsand strong currents to penetrate the port basin. This paper presents a study using the MIKE 21 MA numericalmodel to determine the most optimal mooring layout for a container ship as well as clarify the influence offactors (wind, current, water level and ship’s draft) on the tension force of the mooring lines. The most optimal mooring layout in the study scenarios was uncovered from the simulation results. In addition, wind wasidentified as the factor with the greatest influence on the tension force of the mooring system.

Digital Application of BIM Technology in the Architectural Design Stage

This paper discusses the digital application of building information model (BIM) technology in the architectural design stage. Taking the large-scale comprehensive development project of Guangxi headquarters base as an example, this paper analyzes in detail how BIM technology promotes the intelligence and refinement of the design process. Through the three-dimensional modeling and simulation analysis of BIM technology, the project design has realized the accurate transformation from concept to operation, which not only improves the design efficiency, but also ensures the construction quality and economic benefits. This paper focuses on the application of BIM in the digital design of building structure, the deepening design of steel nodes, as well as the remarkable results in the comprehensive layout optimization of mechanical and electrical pipelines. Through the collision detection and optimization design of the BIM model, the potential design conflicts and construction problems were found and solved at the initial stage of the project, ensuring the efficient promotion and smooth implementation of the project. The research results show that BIM technology, as the core digital tool in the architectural design stage, is of great significance for improving the overall design level of the construction industry and realizing intelligent construction.