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1 – 10 of over 5000Ingrid Schardinger, Florian Botzenhart, Markus Biberacher, Thomas Hamacher and Thomas Blaschke
The purpose of this paper is to outline an integrative modelling approach that includes agricultural and forestry process chains in an energy system model, on a regional scale…
Abstract
Purpose
The purpose of this paper is to outline an integrative modelling approach that includes agricultural and forestry process chains in an energy system model, on a regional scale. The main focus is on land use for biomass production, aimed at satisfying the demands for energy, food, and materials.
Design/methodology/approach
The described model combines geographic modelling with a linear optimisation approach. The cost‐based optimisation of the energy system includes agricultural and forestry process chains. The system's commodities and processes are identified and these are linked appropriately in the specifications of the reference system. Spatial models provided geographically specific input data for the optimisation; these spatial models were based on publicly available data, regional heat and electricity demands, and regional biomass potentials. The optimisation tool was applied in two case studies.
Findings
The optimisation results allow an improved understanding of the interdependencies between regional agricultural and forestry structures and the regional energy system. Future developments of the energy system can be quantified. The application of the model in the case studies has revealed the limits on biomass availability, even in rural areas, and the fossil fuel price sensitivity of an optimal system setup.
Originality/value
Geographic models linked to a forecast model approach and based on publicly available data allow a high spatial resolution by taking into account the region‐specific conditions and mean that the modelling approach is transferrable to other regions. This paper provides an initial insight into the linkage between bottom‐up optimisation and spatial modelling, representing an innovative approach that is yet to be well explored.
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Peiyu Wang, Qian Zhang, Zhimin Li, Fang Wang and Ying Shi
The study aims to devise a comprehensive evaluation model (CEM) for evaluating spatial equity in the layout of elderly service facilities (ESFs) to address the inequity in the…
Abstract
Purpose
The study aims to devise a comprehensive evaluation model (CEM) for evaluating spatial equity in the layout of elderly service facilities (ESFs) to address the inequity in the layout of ESFs within city center communities characterized by limited land resources and a dense elderly population.
Design/methodology/approach
The CEM incorporates a suite of analytical tools, including accessibility assessment, Lorenz curve and Gini coefficient evaluations and spatial autocorrelation analysis. Utilizing this model, the study scrutinized the distributional equity of three distinct categories of ESFs in the city center of Xi’an and proposed targeted optimization strategies.
Findings
The findings reveal that (1) there are disparities in ESFs’ accessibility among different categories and communities, manifesting a distinct center (high) and periphery (low) distribution pattern; (2) there exists inequality in ESFs distribution, with nearly 50% of older adults accessing only 18% of elderly services, and these inequalities are more pronounced in urban areas with lower accessibility, and (3) approximately 14.7% of communities experience a supply-demand disequilibrium, with demand surpassing supply as a predominant issue in the ongoing development of ESFs.
Originality/value
The CEM formulated in this study offers policymakers, urban planners and service providers a scientific foundation and guidance for decision-making or policy amendment by promptly assessing and pinpointing areas of spatial inequity in ESFs and identifying deficiencies in their development.
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Mohammad Hossein Saraei, Ayyoob Sharifi and Mohsen Adeli
The purpose of this study is to optimize the location of hospitals in Gorgan, Iran, to provide desirable services to citizens in the event of an earthquake crisis.
Abstract
Purpose
The purpose of this study is to optimize the location of hospitals in Gorgan, Iran, to provide desirable services to citizens in the event of an earthquake crisis.
Design/methodology/approach
This paper, due to target, is practical and developmental, due to doing method is descriptive and analytical and due to information gathering method is documental and surveying. In the present study, the capabilities of genetic algorithms and imperialist competition algorithm in MATLAB environment in combination with GIS capabilities have been used. In fact, cases such as route blocking, network analysis and vulnerability raster have been obtained from GIS-based on current status data, and then the output of this information is entered as non-random heuristic information into genetic algorithms and imperialist competition algorithm in MATLAB environment.
Findings
After spatial optimization, the hospital service process has become more favorable. Also, the average cost and transfer vector from hospitals to citizens has decreased significantly. By establishing hospitals in the proposed locations, a larger population of citizens can access relief services in less time.
Originality/value
Spatial optimization of relief centers, including hospitals, is one of the issues that can be of significant importance, especially in the event of an earthquake crisis. The findings of the present study and the originality, efficiency and innovation of the used methods can provide a favorable theoretical framework for the success of earthquake crisis management projects.
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Haiyue Fu, Shuchang Zhao and Chuan Liao
This paper aims to promote urban–rural synergy in carbon reduction and achieve the dual carbon goal, reconstruct the low-carbon urban–rural spatial pattern and explore planning…
Abstract
Purpose
This paper aims to promote urban–rural synergy in carbon reduction and achieve the dual carbon goal, reconstruct the low-carbon urban–rural spatial pattern and explore planning strategies for carbon mitigation in urban agglomerations.
Design/methodology/approach
The authors propose the idea of land governance zoning based on low-carbon scenario simulation, using the Beijing–Tianjin–Hebei (BTH) urban agglomeration as the empirical research area. Specifically, the authors analyze its spatiotemporal evolution characteristics of carbon balance over the past two decades and simulate the land use pattern under the scenario of low-carbon emission in 2030. Furthermore, the authors create spatial zoning rules combined with land use transition characteristics to classify the urban agglomeration into carbon sink restoration zone, carbon sink protection zone, carbon control development zone and carbon transition agriculture zone and put forward corresponding targeted governance principals.
Findings
The study findings classify the BTH urban agglomeration into carbon sink restoration zone, carbon sink protection zone, carbon control development zone and carbon transition agriculture zone, which account for 28.1%, 17.2%, 20.1% and 34.6% of the total area, respectively. The carbon sink restoration zone and carbon sink protection zone are mainly distributed in the northern and western parts and Bohai Rim region. The carbon transition agriculture zone and carbon control development zone are mainly distributed in the southeastern plain and Zhangjiakou.
Research limitations/implications
The authors suggest restoring and rebuilding ecosystems mainly in the northwest and east parts to increase the number of carbon sinks and the stability of the ecosystem. Besides, measures should be taken to promote collaborative emission reduction work between cities and optimize industrial and energy structures within cities such as Beijing, Langfang, Tianjin and Baoding. Furthermore, the authors recommend promoting sustainable intensification of agriculture and carefully balance between both economic development and ecological protection in Zhangjiakou and plain area.
Originality/value
The authors propose a zoning method based on the optimization of land use towards low-carbon development by combining “top-down” and “bottom-up” strategies and provide targeted governance suggestions for each region. This study provides policy implications to implement the regional low-carbon economic transition under the “double carbon” target in urban agglomerations in China.
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Prem Chhetri, Booi Kam, Kwok Hung Lau, Brian Corbitt and France Cheong
The purpose of this paper is to explore how a retail distribution network can be rationalised from a spatial perspective to improve service responsiveness and delivery efficiency.
Abstract
Purpose
The purpose of this paper is to explore how a retail distribution network can be rationalised from a spatial perspective to improve service responsiveness and delivery efficiency.
Design/methodology/approach
This paper applies spatial analytics to examine variability of demand, both spatially and from a service delivery perspective, for an auto-parts retail network. Spatial analytics are applied to map the location of stores and customers to represent demand and service delivery patterns and to delineate market areas.
Findings
Results show significant spatial clustering in customer demand; whilst the delivery of products to customers, in contrast, is spatially dispersed. There is a substantial gap between revenue generated and costs. Market area analysis shows significant overlap, whereby stores compete with each other for business. In total, 80 per cent of customers can be reached within a 15-minute-radius, whilst only 20 per cent lies outside the market areas. Segmentation analysis of customers, based on service delivery, also shows the prevalence of the Pareto principle or 80:20 rule whereby 80 per cent of the revenue is generated by 20 per cent of customers.
Practical implications
Spatially integrated strategies are suggested to improve the efficiency of the retail network. It is recommended that less accessible and unprofitable customers could be either charged extra delivery cost or outsourced without the risk of a substantial reduction in revenue or quality of service delivery.
Originality/value
Innovative application of spatial analytics is used to analyse and visualise unit-record sales data to generate practical solutions to improve retail network responsiveness and operational efficiency.
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Morteza Asadi and Jalal Karami
The aim of this study was to determine the number of shelters, specify some optimal paths among building blocks towards shelters, and assign population to shelters.
Abstract
Purpose
The aim of this study was to determine the number of shelters, specify some optimal paths among building blocks towards shelters, and assign population to shelters.
Design/methodology/approach
Imperialist competition algorithm (ICA) and particle swarm optimization (PSO) were used to optimize the objectives of this study.
Findings
The optimal value for PSO objective function was with the number of function evaluations (NFE) of 5300 and the optimal value of ICA objective function was with NFE of 1062. Repetition test for both algorithms showed that imperialist competition algorithm enjoys better stability and constancy and higher speed of convergence compared to particle swarm algorithm. This has been also shown in larger environments. 92% of the existing populations have access to shelters at a distance of less than600 meters. This means that evacuation from the building blocks to shelters takes less than 8 minutes. The average distance from a block (for example, a residential complex) to an optimal shelter is approximately273meters. The greatest risk of route and shelter has been 239 and 121, respectively.
Research limitations/implications
To address these goals, four following objective functions were considered: a) minimization of the distance for getting all the people to shelters b) the lowest total risk of the discharge path c) minimization of the total time required to transfer people to shelters or hospitals if necessary, and d) the lowest total risk in shelters.
Social implications
Over the recent decades, the frequency of so-called ‘natural’ disasters has increased significantly worldwide and resulted in escalating human and economic losses. Among them, the earthquake is one of the major concerns of the various stakeholders related to urban planning.
Originality/value
In addition, the maximum time of discharge from the helter to the hospital has been 17 minutes, which means the presence of good access to selected shelters.
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Pengfei Zheng and Gonglian Dai
This paper aims to obtain the further and overall generation about the static characteristics of the structure for the better application of the structure.
Abstract
Purpose
This paper aims to obtain the further and overall generation about the static characteristics of the structure for the better application of the structure.
Design/methodology/approach
Through nonlinear finite element simulation, serials of comparative analyses are performed on this structure and other three assumed structures, which illustrate the effect of the main part of the structure on the structural static properties. Meanwhile, adopting the first order method, spatial cable force optimization makes the structural mechanic more rational.
Findings
Under same level stress, this three‐main‐truss and three‐cable‐plane bridge could save almost 38.8 percent vertical chords materials consumption at least. In contrast, this bridge has a lower lateral torsional stiffness, considering the key to raise the lateral and torsional stiffness is enhancing axial stiffness of plane bracing, the suitable plane bracing members area is twice as the original area. After rational optimization, the cable tension ratio between the mid‐cable plane and the two side‐cable planes ranges from 1.09 to 1.14.
Originality/value
The work in this paper of the comparative analysis could give other engineers a way to a deep analysis method for the structural analysis, especially in civil engineering. The conclusions would provide other designers some applied advice.
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Jéderson da Silva, Jucélio Tomás Pereira and Diego Amadeu F. Torres
The purpose of this paper is to propose a new scheme for obtaining acceptable solutions for problems of continuum topology optimization of structures, regarding the distribution…
Abstract
Purpose
The purpose of this paper is to propose a new scheme for obtaining acceptable solutions for problems of continuum topology optimization of structures, regarding the distribution and limitation of discretization errors by considering h-adaptivity.
Design/methodology/approach
The new scheme encompasses, simultaneously, the solution of the optimization problem considering a solid isotropic microstructure with penalization (SIMP) and the application of the h-adaptive finite element method. An analysis of discretization errors is carried out using an a posteriori error estimator based on both the recovery and the abrupt variation of material properties. The estimate of new element sizes is computed by a new h-adaptive technique named “Isotropic Error Density Recovery”, which is based on the construction of the strain energy error density function together with the analytical solution of an optimization problem at the element level.
Findings
Two-dimensional numerical examples, regarding minimization of the structure compliance and constraint over the material volume, demonstrate the capacity of the methodology in controlling and equidistributing discretization errors, as well as obtaining a great definition of the void–material interface, thanks to the h-adaptivity, when compared with results obtained by other methods based on microstructure.
Originality/value
This paper presents a new technique to design a mesh made with isotropic triangular finite elements. Furthermore, this technique is applied to continuum topology optimization problems using a new iterative scheme to obtain solutions with controlled discretization errors, measured in terms of the energy norm, and a great resolution of the material boundary. Regarding the computational cost in terms of degrees of freedom, the present scheme provides approximations with considerable less error if compared to the optimization process on fixed meshes.
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States that the homo economicus abstraction remains dominant in economics, despite a range of criticisms of its use over the years. Many institutionalists, post‐Keynesians…
Abstract
States that the homo economicus abstraction remains dominant in economics, despite a range of criticisms of its use over the years. Many institutionalists, post‐Keynesians, neo‐Austrians and social economists have insisted that economic analysis must be conducted in an explicit historical context, where the difficulties which economic decision‐makers face, because of time irreversibility, structural change and fundamental uncertainty, are taken into account, as well as non‐economic influences on economic behaviour. Understandably, there has been a reluctance to construct a competing abstraction with formal properties which are comparable to those of the homo economicus construct. It is argued in this paper that the development of an alternative behavioural abstraction constitutes an important goal, both in terms of clarifying the limitations of homo economicus and providing an analytical basis upon which investigations of economic behaviour in historical time can be built.
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Donghai Wang, Wei Sun, Zhihui Gao and Hui Li
In many cases, the external pipelines of aero-engine are subjected to random excitation. The purpose of this paper is to reduce the vibration response of the pipeline system…
Abstract
Purpose
In many cases, the external pipelines of aero-engine are subjected to random excitation. The purpose of this paper is to reduce the vibration response of the pipeline system effectively by adjusting the hoop layout.
Design/methodology/approach
In this paper, a spatial pipeline supported by multi-hoops is taken as the object, the methods of solution of the vibration response of the pipeline system by using pseudo excitation and hoop layouts optimization with amplitude reduction of vibration response as the goal are presented. First, the finite element model of the spatial pipeline system is presented. Then, an optimization model spatial pipeline is established. Finally, a case study is carried out to prove the rationality of the random vibration response analysis of the pipeline system. Furthermore, the proposed optimization model and genetic algorithm are applied to optimize the hoop layout.
Findings
The results show that the maximum response variance after optimization is reduced by 32.8%, which proves the rationality of the developed hoop layout optimization method.
Originality/value
The pseudo excitation method is used to solve the vibration response of aero-engine pipeline system, and the optimization of the hoop layout for aero-engine spatial pipelines under random excitation to reduce random vibration response is studied systematically.
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