作者：
Li, YongjieTang, LiYe, MianZhang, XuejunXihua Univ
Minist Educ Intelligent Air Ground Fus Vehicle & Control Engn Chengdu Sichuan Peoples R China Xihua Univ
Sch Aeronaut & Astronaut Chengdu Sichuan Peoples R China Xihua Univ
Sch Automobile & Transportat Chengdu Sichuan Peoples R China
Under the influence of COVID-19, some residents have been sealed at home. To reduce the risk of cross-infection when distributing materials, how to safely and effectively has become a major problem. Considering that t...
详细信息
ISBN:
(数字)9780784484869
ISBN:
(纸本)9780784484869
Under the influence of COVID-19, some residents have been sealed at home. To reduce the risk of cross-infection when distributing materials, how to safely and effectively has become a major problem. Considering that the application technology of drones in the field of logistics has become more and more mature in recent years, the joint distribution mode of trucks and drones has been proposed. According to the characteristics of the problem, a three-stage solution algorithm is designed;the first stage is to set the safety distance threshold between the demand point and the truck stop and use the K-means algorithm to find the truck stop site;the second stage is to design an improved ALNS (Adaptive Large Neighborhood Search) algorithm to optimize the drone path and compare the results with the optimizer Gurobi;and the third stage is to optimize the truck route. All three phases are implemented using python programming, and the second stage of the core is studied and evaluated, which shows that the ALNS algorithm solves faster and with better results than Gurobi.
Viscous dampers (VDs) are currently used an effective earthquake risk reduction measure. Due to the high cost of this type of dampers, an optimal damper layout across the stories will specifically improve the seismic ...
详细信息
Viscous dampers (VDs) are currently used an effective earthquake risk reduction measure. Due to the high cost of this type of dampers, an optimal damper layout across the stories will specifically improve the seismic response and reduce building costs. This paper introduces a new simple three-stage method to determine the optimal placement of VDs on different stories of reinforced concrete structures. In the first stage, the damping demand of each story was determined using the distribution pattern of earthquake forces by the equivalent static method and the story velocity obtained through time-history analysis. In the second stage, the number of dampers required for the structure was calculated, and the location and damping percentage of dampers were precisely determined through an iterative process in the third stage. An indicator representing all basic structural responses was used to evaluate the multiple choices for the damper layout. This process was evaluated for 4, 8 story concrete frames under a near-field earthquake. The results indicated the efficiency of the proposed method in determining the location and damping of VDs on different stories of the structure.
In a container terminal, the arriving times and handling volumes of the vessels are uncertain. The arriving times of the external trucks and the number of containers which are needed to be brought into or retrieved fr...
详细信息
In a container terminal, the arriving times and handling volumes of the vessels are uncertain. The arriving times of the external trucks and the number of containers which are needed to be brought into or retrieved from a container terminal by external trucks within a period are also uncertain. Yard crane (YC) scheduling is under uncertainty. This paper addresses a YC scheduling problem with uncertainty of the task groups' arriving times and handling volumes. We do not only optimize the efficiency of YC operations, but also optimize the extra loss caused by uncertainty for reducing risk of adjusting schedule as the result of the task groups' arriving times and handling volumes deviating from their plan. A mathematical model is proposed for optimizing the total delay to the estimated ending time of all task groups without uncertainty and the extra loss under all uncertain scenarios. Furthermore, a GA-based framework combined with three-stage algorithm is proposed to solve the problem. Finally, the proposed mathematical model and approach are validated by numerical experiments.
Recently, resilience studies have become an indispensable tool for sustainable operation of energy infrastructure. In line with the need, this study presents a mathematical model to enhance resilience level of power d...
详细信息
Recently, resilience studies have become an indispensable tool for sustainable operation of energy infrastructure. In line with the need, this study presents a mathematical model to enhance resilience level of power distribution systems against natural disasters. The model is designed as a three-stage algorithm according to system operators' actions. The first stage schedules pre-event actions. At this stage, forecasts about the approaching disaster as well as fragility curves of system components are used to identify failure probability of system components. The failure probabilities are used to trip out the lines as much as possible to defensively operate the distribution network, and advantages of alternatives such as distributed energy resources and normally-open switches are taken to serve critical loads. The second stage is to monitor system operating conditions during the event and identify the status of system components. The third stage mainly focuses on scheduling post-event actions. At this stage, based on real data about different elements of the network, available alternatives are taken to restore as much critical load as possible. To evaluate performance of the model, it is applied to a distribution test system and the results are discussed in detail.
暂无评论