Abstract In this thesis, multiagent system specifications, multiagent system architectures, agent communication languages and agent communication protocols, automatic abstracting based on multiagent technologies are studied. Some concerned problems of designs and realization of automatic abstracting systems based on multiagent technologies are studied, too. Chapter 1 shows the significance and objectives of the thesis, its main contents are summarized, and innovations of the thesis are showed. Some basic concepts of agents and multiagent systems are studied in Chapter 2. The definitions of agents and multiagent systems are given, and the theory, technologies and applications of multiagent systems are summarized. Furthermore, some important studying trends of multiagent systems are set forward. Multiagent system specifications are studied in Chapter 3. MAS/KIB—a multiagent system specification is built using mental states such as K (Know), B (Belief), and I (Intention), its grammar and semanteme are discussed, axioms and inference rules are given, and some properties are researched. We also compare MAS/KIB with other existing specifications. MAS/KIB has the following characteristics: (1) each agent has its own world outlook; (2) no global data in the system; (3) processes of state changes are used as indexes to systems; (4) it has the characteristics of not only time series logic but also dynamic logic; and (5) interactive actions are included. The architectures of multiagent systems are studied in Chapter 4. First, we review some typical architecture of multiagent systems, agent network architecture, agent federated architecture, agent blackboard architecture, and Foundation of Intelligent Physical Agent(FIPA) architecture. For the first time, we set forward and study the layering and partitioning models of the architectures of multiagent systems, organizing architecture models, and interoperability architecture model of multiagent systems. Chapter 5 studies agent communication languages. We study FIPA Agent Communication Language(ACL) message grammar, Communicative Act(CA) types, ACL semantics and Agent Communication Protocols. The string grammar of ACL messages and SL grammar represented by EBNF are given, and a new ACL semantic model is set forward. We study automatic abstracting based on multiagent technologies in Chapter 6. For the first time, the idea of constructing automatic abstracting systems based on multiagent technologies is set forward, and the necessity and feasibility of constructing such systems are set forth. The architecture of automatic abstracting systems based on multiagent technologies is provided, and the basic elements and mutual relations are studied. We set forth the working principle of the automatic abstracting systems based on multiagent technologies and how the contradiction of domain currency and abstract quality of automatic abstracting systems is resolved. Studies, simulation analysis and design of the automatic abstracting experimental system based on multiagent technologies(ABES/MAT) are made in Chapter 7. We study the architecture of ABES/MAT, and set forth its basic elements and mutual relations. The user model and mathematics descriptions of ABES/MAT in the Internet environment are provided. Three coordination algorithms that synthetically use environment information, system information and history information are set forward. Then, we analyze the performance of ABES/MAT based on the simulations, and get suitable number fo abstracting agents for each domain in a given load. Finally, we compare the three coordination algorithms. The realization of ABES/MAT is introduced in Chapter 8. Firstly, we study the problem of the agentification of legacy systems, and show how to realize the agentification of glanc, ladies and news. Then, the architectures and functions of Coordination Management Agent(CMA) and Information Agent(IA) are set forth. The agent naming grammar represented by EBNF is given., In the following, we explain the designed agent communicative acts and management Abstract In some thesis, multiagent system architectures, multiagent system architectures, agent in communication languages ​​and agent communication protocols, automatic abstracting based on multiagent technologies are studied. Some concerned problems of designs and realization of automatic abstracting systems based on multiagent technologies are studied, too. Chapter 1 shows the significance and objectives of the the thesis, its main contents are summarized, and innovations of the the thesis are shown. Some basic concepts of agents and multiagent systems are studied in Chapter 2. The definitions of agents and multiagent systems are given, and the theory, technologies and applications of multiagent systems are summarized. Further, some important studying trends of multiagent systems are set forward. Multiagent system specifications are studied in Chapter 3. MAS / KIB-a multiagent system specification is built using a mental states such as K Know, B (Belief), and I (Intention), its grammar and semanteme are discussed, axioms and inference rules are given, and some properties are currently researched. We also compare MAS / KIB with other existing specifications. 2) no global data in the system; (3) processes of state changes are used as indexes to systems; (4) it has the characteristics of not only time series logic but also dynamic logic; and (5) interactive actions are included. The architectures of multiagent systems are studied in Chapter 4. First, we review some typical architecture of multiagent systems, agent network architecture, agent federated architecture, agent blackboard architecture, and Foundation of Intelligent Physical Agent (FIPA) architecture. For the first time, we set forward and study the layering and partitioning models of the architectures of multiagent systems, organizing architecture models, and interoperability architecture model of multiagent systems. Chapter 5 stu dies agent communication languages. We study FIPA Agent Communication Language (ACL) messages grammar, Communicative Act (CA) types, ACL semantics and Agent Communication Protocols. The string grammar of ACL messages and SL grammar represented by EBNF are given, and a new ACL We study automatic abstracting based on multiagent technologies in Chapter 6. For the first time, the idea of ​​constructing automatic abstracting systems based on multiagent technologies is set forward, and the necessity and feasibility of constructing such systems is set forth. The architecture of automatic abstracting systems based on multiagent technologies is provided, and the basic elements and mutual relations are studied. We set forth the working principle of the automatic abstracting systems based on multiagent technologies and how the contradiction of domain currency and abstract quality of automatic abstracting systems is resolved. Studies, simulation analysis and design of the automatic abstracting experimental system based on multiagent technologies (ABES / MAT) are made in Chapter 7. We study the architecture of ABES / MAT, and set forth its basic elements and mutual relations. The user model and mathematics descriptions of ABES / MAT in the Internet environment are provided. Three coordination algorithms that synthetically use environment information, system information and history information are set forward. Then, we analyze the performance of ABES / MAT based on the simulations, and get suitable number fo abstracting agents for each domain in a Given load. Finally, we compare the three coordination algorithms. The realization of ABES / MAT is introduced in Chapter 8. Firstly, we study the problem of the identification of legacy systems, and show how to realize the identification of glanc, ladies and news . Then, the architectures and functions of Coordination Management Agent (CMA) and Information Agent (IA) are set forth. The agent naming grammar represented by EBNF is given., In the following, we explain the designed agent communicative acts and management