Font Size: a A A

Emergency Resource Management Approach Based On HTN Planning

Posted on:2013-01-03Degree:DoctorType:Dissertation
Country:ChinaCandidate:Z WangFull Text:PDF
GTID:1266330398487210Subject:Systems Engineering
Abstract/Summary:PDF Full Text Request
Various frequent emergencies, which threaten the harmony and stability of society severely, request the high reaction ability of government. Because of the sudden, unconventionality, hierarchy, resource scarcity and timeliness of emergency response, complex emergency decision-making issues cannot be solved by establishing idealized mathematical model. Hierarchy Task Network (HTN) planning, which obtains the plan by task decomposition, can simulate the whole process of emergency decision-making from strategical levels to operational levels. Furthermore, HTN planning can express complex emergency domain knowledge by logical language. Therefore, it is widely used in emergency decision-making. Unfortunately, the task network is adopted in HTN planning to describe action reasoning process. For this reason, HTN planning is difficult to control the resource state to deal with resource management issues. Emergency decision-making contains the coupling relationship of task planning and resource scheduling. In task planning, different task execution methods require different resources. Meanwhile, emergency resource profiles affect the decision-making behaviors of emergency responders, such as choosing emergency goals, strategies, tacticses and operations. Hence, HTN planning and resource scheduling in emergency decision-making cannot be treated as two independent processes. On the contrary, in order to support emergency response efficiently, the resource management ability must be enhanced for HTN planning.Focusing on the coupling relationship of task planning and resource scheduling of emergency response, resource management approach based on HTN planning in emergency decision-making is studied. The contributions of this thesis are as follows:In order to identify heterogeneous emergency resource information from multiple participating units, an emergency resource ontology modeling approach is designed. Based on OWL ontology language (Web Ontology Language), emergency resource ontology model is established in the approach to obtain human resource information and material resource information. Based on emergency resource ontology model, emergency resource ontology management is established to transform emergency resource information from OWL ontology language to HTN logical language.Hierarchical resource reasoning is one of the key issues to successfully apply HTN planning into emergency decision-making. This thesis proposes a Resource Enhanced HTN (REHTN) planning approach for emergency decision-making with the objective to enhance the expressive power and improve the processing speed of hierarchical resource reasoning. In the approach, resource timelines are defined to describe various resource variables and constraints. Top-down resource reasoning is used for decomposing the resource constraints of upper-level tasks into those of lower-level tasks. Meanwhile, resource and temporal constraints of tasks in different branches are processed by causal links. In primitive task layer, resource profiles of consumable resources and reusable resources are checked by separate resource allocation processes. Furthermore, a constraint propagation accelerator is designed to speed up hierarchal resource reasoning.Emergency resource shortage issue includes two aspects. On the one hand, emergency goals must be achieved as far as possible by full using of existing resources. On the other hand, temporary unachieved emergency goals must be analyzed to identify the resource shortage information. Emergency responders can achieve those emergency goals by requesting reinforcements according to the resource shortage information. An REHTN approach for resource shortage (REHTNRS) is proposed for emergency resource shortage issue. The issue is described in REHTNRS by expanding the syntax of REHTN. In the describing process, plan goals are modeled as soft goals, including achieved goals, unachieved goals and conditional achieved goals. Meanwhile, conditional achieved goals can be accomplished by the tasks with resource shortage stamps. In the processing algorithm of the resource shortage issue, resource shortage identification method adopts resource shortage stamps to identify the resource shortage in planning. Meanwhile, anytime heuristic algorithm with resource shortage stamps is designed.Emergency resource exception happens frequently in emergency action plan implementing. Based on the establishing of integrated planning and execution framework, an emergency resource exception treatment scheme is designed. The scheme includes emergency resource exception monitoring, analysis and disposing.
Keywords/Search Tags:Emergency decision-making, Unconventional emergency, Hierarchy tasknetwork planning, Intelligent planning, Resource reasoning, Knowledge modeling, Resource scarcity, Resource exception
PDF Full Text Request
Related items