scholarly journals Sequential Model for Long-Term Planning of Building Renewal and Capital Improvement

2021 ◽  
Vol 13 (17) ◽  
pp. 9575
Author(s):  
Robert Bucoń ◽  
Agata Czarnigowska
Keyword(s):  
Programming Model ◽  
Residential Buildings ◽  
Planning Horizon ◽  
Mixed Integer ◽  
Building Performance ◽  
Optimal Sequence ◽  
Specific Order ◽  
Improvement Measures ◽  
Mutually Independent

The paper puts forward a mixed integer linear programming model to support the long-term planning and budgeting for renewal and capital improvements of residential buildings, i.e., to select the optimal sequence of repair and improvement actions over a predefined planning horizon. The input is provided by the evaluation of the building performance according to a set of criteria. Then a set of possible repairs, replacements and improvements needs to be proposed together with the estimates of their cost and benefits; the latter are expressed by increments of building performance ratings according to predefined criteria. The renewal and modernization measures are not mutually independent: at least some of them are complementary and should be carried out in a specific order. The optimization problem was to define the order of renewal/improvement measures resulting with the highest benefits available within the budget, or to achieve the required levels of building performance at the lowest cost. A unique feature of the model is the approach to the constraints on sequential relationships between the measures and to their selection. The model can be used to construct long-term renewal and capital improvement plans.

scholarly journals Multi-Period Network Design Problem in Regional Hazardous Waste Management Systems

2019 ◽  
Vol 16 (11) ◽  
pp. 2042 ◽  
Author(s):  
Jun Zhao ◽  
Lixiang Huang
Keyword(s):  
Network Design ◽  
Design Problem ◽  
Programming Model ◽  
Planning Horizon ◽  
Network Design Problem ◽  
Mixed Integer ◽  
Hazardous Wastes ◽  
Total Risk ◽  
Total Cost ◽  
Treatment And Disposal

The management of hazardous wastes in regions is required to design a multi-echelon network with multiple facilities including recycling, treatment and disposal centers servicing the transportation, recycling, treatment and disposal procedures of hazardous wastes and waste residues. The multi-period network design problem within is to determine the location of waste facilities and allocation/transportation of wastes/residues in each period during the planning horizon, such that the total cost and total risk in the location and transportation procedures are minimized. With consideration of the life cycle capacity of disposal centers, we formulate the problem as a bi-objective mixed integer linear programming model in which a unified modeling strategy is designed to describe the closing of existing waste facilities and the opening of new waste facilities. By exploiting the characteristics of the proposed model, an augmented ε -constraint algorithm is developed to solve the model and find highly qualified representative non-dominated solutions. Finally, computational results of a realistic case demonstrate that our algorithm can identify obviously distinct and uniformly distributed representative non-dominated solutions within reasonable time, revealing the trade-off between the total cost and total risk objectives efficiently. Meanwhile, the multi-period network design optimization is superior to the single-period optimization in terms of the objective quality.

scholarly journals The Nutritious Supply Chain: Optimizing Humanitarian Food Assistance

2021 ◽  
pp. ijoo.2019.0047
Author(s):  
Koen Peters ◽  
Sérgio Silva ◽  
Rui Gonçalves ◽  
Mirjana Kavelj ◽  
Hein Fleuren ◽  
...  
Keyword(s):  
Supply Chain ◽  
Programming Model ◽  
Food Assistance ◽  
Decision Makers ◽  
Mixed Integer ◽  
Sourcing Strategies ◽  
Humanitarian Agency ◽  
Operational Excellence ◽  
Functional Areas

The World Food Programme (WFP) is the largest humanitarian agency fighting hunger worldwide, reaching approximately 90 million people with food assistance across 80 countries each year. To deal with the operational complexities inherent in its mandate, WFP has been developing tools to assist its decision makers with integrating supply chain decisions across departments and functional areas. This paper describes a mixed integer linear programming model that simultaneously optimizes the food basket to be delivered, the sourcing plan, the delivery plan, and the transfer modality of a long-term recovery operation for each month in a predefined time horizon. By connecting traditional supply chain elements to nutritional objectives, we are able to make significant breakthroughs in the operational excellence of WFP’s most complex operations. We show three examples of how the optimization model is used to support operations: (1) to reduce the operational costs in Iraq by 12% without compromising the nutritional value supplied, (2) to manage the scaling-up of the Yemen operation from three to six million beneficiaries, and (3) to identify sourcing strategies during the El Niño drought of 2016.

scholarly journals UAVs Path Planning under a Bi-Objective Optimization Framework for Smart Cities

Electronics ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1193
Author(s):  
Subrata Saha ◽  
Alex Elkjær Vasegaard ◽  
Izabela Nielsen ◽  
Aneta Hapka ◽  
Henryk Budzisz
Keyword(s):  
Programming Model ◽  
Smart Cities ◽  
Low Cost ◽  
Mixed Integer ◽  
Neighborhood Search ◽  
Cumulative Probability ◽  
Optimal Sequence ◽  
Optimization Framework ◽  
Benchmark Instances ◽  
Disaster Monitoring

Unmanned aerial vehicles (UAVs) have been used extensively for search and rescue operations, surveillance, disaster monitoring, attacking terrorists, etc. due to their growing advantages of low-cost, high maneuverability, and easy deployability. This study proposes a mixed-integer programming model under a multi-objective optimization framework to design trajectories that enable a set of UAVs to execute surveillance tasks. The first objective maximizes the cumulative probability of target detection to aim for mission planning success. The second objective ensures minimization of cumulative path length to provide a higher resource utilization goal. A two-step variable neighborhood search (VNS) algorithm is offered, which addresses the combinatorial optimization issue for determining the near-optimal sequence for cell visiting to reach the target. Numerical experiments and simulation results are evaluated in numerous benchmark instances. Results demonstrate that the proposed approach can favorably support practical deployability purposes.

scholarly journals Production Planning Problem of a Two-Level Supply Chain with Production-Time-Dependent Products

2021 ◽  
Vol 11 (20) ◽  
pp. 9687
Author(s):  
Jun-Hee Han ◽  
Ju-Yong Lee ◽  
Bongjoo Jeong
Keyword(s):  
Supply Chain ◽  
Production Planning ◽  
Programming Model ◽  
Planning Horizon ◽  
Mixed Integer ◽  
Planning Problem ◽  
Manufacturing Plant ◽  
Production Lines ◽  
Multiple Production ◽  
Production Planning Problem

This study considers a production planning problem with a two-level supply chain consisting of multiple suppliers and a manufacturing plant. Each supplier that consists of multiple production lines can produce several types of semi-finished products, and the manufacturing plant produces the finished products using the semi-finished products from the suppliers to meet dynamic demands. In the suppliers, different types of semi-finished products can be produced in the same batch, and products in the same batch can only be started simultaneously (at the same time) even if they complete at different times. The purpose of this study is to determine the selection of suppliers and their production lines for the production of semi-finished products for each period of a given planning horizon, and the objective is to minimize total costs associated with the supply chain during the whole planning horizon. To solve this problem, we suggest a mixed integer programming model and a heuristic algorithm. To verify performance of the algorithm, a series of tests are conducted on a number of instances, and the results are presented.

scholarly journals Optimization and evaluation of operation strategies for regional distributed energy system

2020 ◽  
Vol 194 ◽  
pp. 01015
Author(s):  
Jingyi Yuan ◽  
Miao Li ◽  
Xiaoyu Liu ◽  
kun Xu
Keyword(s):  
Programming Model ◽  
Residential Buildings ◽  
Energy System ◽  
Pollutant Emissions ◽  
Mixed Integer ◽  
Distributed Energy ◽  
Real Time Control ◽  
Network Connection ◽  
Distributed Energy System ◽  
Electricity Network

With the development of energy technologies, the electricity, cooling and heating are tightly connected to improve the overall efficiency of distributed energy systems. These systems satisfy simultaneously different energy demands at building level (hotels, offices and residential buildings). The optimal capacity of technologies from numerous alternatives and optimal operating strategy as well as electricity network connection was investigated in this paper in order to achieve economic and environmental gains. A mixed integer linear programming model was also used for multi-objective optimization to minimize total cost and pollutant emissions. The results show that distributed energy system with electricity network as well as real time control can realize the better performance through multi-optimization from regional viewpoint. However, the results are on the contrary aiming at individual hotels and offices. The performance advancement of this system can only be reflected in residential buildings.

scholarly journals A Four-Type Decision-Variable MINLP Model for a Supply Chain Network Design

2010 ◽  
Vol 2010 ◽  
pp. 1-16 ◽  
Author(s):  
M. M. Monteiro ◽  
J. E. Leal ◽  
F. M. P. Raupp
Keyword(s):  
Supply Chain ◽  
Programming Model ◽  
Planning Horizon ◽  
Mixed Integer ◽  
Decision Variable ◽  
Abc Classification ◽  
Computational Implementation ◽  
Minlp Model ◽  
Nonlinear Programming Model ◽  
Outer Approximation Algorithm

We propose a mixed integer nonlinear programming model for the design of a one-period planning horizon supply chain with integrated and flexible decisions on location of plants and of warehouses, on levels of production and of inventory, and on transportation models, considering stochastic demand and the ABC classification for finished goods, which is an NP-hard industrial engineering optimization problem. Furthermore, computational implementation of the proposed model is presented through the direct application of the outer approximation algorithm on some randomly generated supply chain data.

Operator- and user-based rebalancing strategy for bike-sharing systems

2021 ◽  
pp. 1-12
Author(s):  
Peng-Sheng You ◽  
Yi-Chih Hsieh
Keyword(s):  
Dynamic Pricing ◽  
Programming Model ◽  
Supply And Demand ◽  
Planning Horizon ◽  
Sensitivity Analyses ◽  
Mixed Integer ◽  
Time Problem ◽  
Bike Sharing ◽  
Total Profit ◽  
The Impact

Leveraging their networks, bike rental companies usually provide customers with services for renting and returning bikes at different bike stations. Over time, however, rental networks may encounter problems with unbalanced bike stocks. The potential imbalance between supply and demand at bike stations may result in lost sales for stations with relatively high demand and underutilization for stations with relatively low demand. This paper proposed a constrained mixed-integer programming model that uses operator-based redistribution and user-based price approach to rebalance bikes across bike stations. This paper aims to maximize total profit over a planning horizon by determining operator-based bike transfers and dynamic pricing. The proposed model is a non-deterministic polynomial-time problem, and thus, a heuristic was developed based on linear programming and evolutionary computation to perform model solving. Numerical experiments reveal that the proposed method performed better than Lingo, a well-known commercial software. Sensitivity analyses were also performed to investigate the impact of changes in system parameters on computational results.

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