• Title/Summary/Keyword: Intelligent Agent

Search Result 700, Processing Time 0.03 seconds

A Multi-agent based Cooperation System for an Intelligent Earthwork (지능형 토공을 위한 멀티에이전트 기반 협업시스템)

  • Kim, Sung-Keun
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.34 no.5
    • /
    • pp.1609-1623
    • /
    • 2014
  • A number of studies have been conducted recently regarding the development of automation systems for the construction sector. Much of this attention has focused on earthwork because it is highly dependent on construction machines and is regarded as being basic for the construction of buildings and civil works. For example, technologies are being developed in order to enable earthwork planning based on construction site models that are constructed by automatic systems and to enable construction equipment to perform the work based on the plan and the environment. There are many problems that need to be solved in order to enable the use of automatic earthwork systems in construction sites. For example, technologies are needed for enabling collaborations between similar and different kinds of construction equipment. This study aims to develop a construction system that imitates collaborative systems and decision-making methods that are used by humans. The proposed system relies on the multi-agent concept from the field of artificial intelligence. In order to develop a multi-agent-based system, configurations and functions are proposed for the agents and a framework for collaboration and arbitration between agents is presented. Furthermore, methods are introduced for preventing duplicate work and minimizing interference effects during the collaboration process. Methods are also presented for performing advance planning for the excavators and compactors that are involved in the construction. The current study suggests a theoretical framework and evaluates the results using virtual simulations. However, in the future, an empirical study will be conducted in order to apply these concepts to actual construction sites through the development of a physical system.

A Multi-Agent framework for Distributed Collaborative Filtering (분산 환경에서의 협력적 여과를 위한 멀티 에이전트 프레임워크)

  • Ji, Ae-Ttie;Yeon, Cheol;Lee, Seung-Hun;Jo, Geun-Sik;Kim, Heung-Nam
    • Journal of Intelligence and Information Systems
    • /
    • v.13 no.3
    • /
    • pp.119-140
    • /
    • 2007
  • Recommender systems enable a user to decide which information is interesting and valuable in our world of information overload. As the recent studies of distributed computing environment have been progressing actively, recommender systems, most of which were centralized, have changed toward a peer-to-peer approach. Collaborative Filtering (CF), one of the most successful technologies in recommender systems, presents several limitations, namely sparsity, scalability, cold start, and the shilling problem, in spite of its popularity. The move from centralized systems to distributed approaches can partially improve the issues; distrust of recommendation and abuses of personal information. However, distributed systems can be vulnerable to attackers, who may inject biased profiles to force systems to adapt their objectives. In this paper, we consider both effective CF in P2P environment in order to improve overall performance of system and efficient solution of the problems related to abuses of personal data and attacks of malicious users. To deal with these issues, we propose a multi-agent framework for a distributed CF focusing on the trust relationships between individuals, i.e. web of trust. We employ an agent-based approach to improve the efficiency of distributed computing and propagate trust information among users with effect. The experimental evaluation shows that the proposed method brings significant improvement in terms of the distributed computing of similarity model building and the robustness of system against malicious attacks. Finally, we are planning to study trust propagation mechanisms by taking trust decay problem into consideration.

  • PDF

L-CAA : An Architecture for Behavior-Based Reinforcement Learning (L-CAA : 행위 기반 강화학습 에이전트 구조)

  • Hwang, Jong-Geun;Kim, In-Cheol
    • Journal of Intelligence and Information Systems
    • /
    • v.14 no.3
    • /
    • pp.59-76
    • /
    • 2008
  • In this paper, we propose an agent architecture called L-CAA that is quite effective in real-time dynamic environments. L-CAA is an extension of CAA, the behavior-based agent architecture which was also developed by our research group. In order to improve adaptability to the changing environment, it is extended by adding reinforcement learning capability. To obtain stable performance, however, behavior selection and execution in the L-CAA architecture do not entirely rely on learning. In L-CAA, learning is utilized merely as a complimentary means for behavior selection and execution. Behavior selection mechanism in this architecture consists of two phases. In the first phase, the behaviors are extracted from the behavior library by checking the user-defined applicable conditions and utility of each behavior. If multiple behaviors are extracted in the first phase, the single behavior is selected to execute in the help of reinforcement learning in the second phase. That is, the behavior with the highest expected reward is selected by comparing Q values of individual behaviors updated through reinforcement learning. L-CAA can monitor the maintainable conditions of the executing behavior and stop immediately the behavior when some of the conditions fail due to dynamic change of the environment. Additionally, L-CAA can suspend and then resume the current behavior whenever it encounters a higher utility behavior. In order to analyze effectiveness of the L-CAA architecture, we implement an L-CAA-enabled agent autonomously playing in an Unreal Tournament game that is a well-known dynamic virtual environment, and then conduct several experiments using it.

  • PDF

Location Trigger System for the Application of Context-Awareness based Location services

  • Lee, Yon-Sik;Jang, Min-Seok
    • Journal of the Korea Society of Computer and Information
    • /
    • v.24 no.10
    • /
    • pp.149-157
    • /
    • 2019
  • Recent research has been actively carried out on systems that want to optimize resource utilization by analyzing the intended behavior and pattern of behavior of objects (users, consumers). A service system that applies information about an object's location or behavior must include a location trigger processing system for tracking an object's real-time location. In this paper, we analyze design problems for the implementation of a context-awareness based location trigger system, and present system models based on analysis details. For this purpose, this paper introduces the concept of location trigger for intelligent location tracking techniques about moving situations of objects, and suggests a mobile agent system with active rules that can perform monitoring and appropriate actions based on sensing information and location context information, and uses them to design and implement the location trigger system for context-awareness based location services. The proposed system is verified by implementing location trigger processing scenarios and trigger service and action service protocols. In addition, through experiments on mobile agents with active rules, it is suggested that the proposed system can optimize the role and function of the application system by using rules appropriate to the service characteristics and that it is scalable and effective for location-based service systems. This paper is a preliminary study for the establishment of an optimization system for utilizing resources (equipment, power, manpower, etc.) through the active characteristics of systems such as real-time remote autonomous control and exception handling over consumption patterns and behavior changes of power users. The proposed system can be used in system configurations that induce optimization of resource utilization through intelligent warning and action based on location of objects, and can be effectively applied to the development of various location service systems.

Medical Diagnosis Problem Solving Based on the Combination of Genetic Algorithms and Local Adaptive Operations (유전자 알고리즘 및 국소 적응 오퍼레이션 기반의 의료 진단 문제 자동화 기법 연구)

  • Lee, Ki-Kwang;Han, Chang-Hee
    • Journal of Intelligence and Information Systems
    • /
    • v.14 no.2
    • /
    • pp.193-206
    • /
    • 2008
  • Medical diagnosis can be considered a classification task which classifies disease types from patient's condition data represented by a set of pre-defined attributes. This study proposes a hybrid genetic algorithm based classification method to develop classifiers for multidimensional pattern classification problems related with medical decision making. The classification problem can be solved by identifying separation boundaries which distinguish the various classes in the data pattern. The proposed method fits a finite number of regional agents to the data pattern by combining genetic algorithms and local adaptive operations. The local adaptive operations of an agent include expansion, avoidance and relocation, one of which is performed according to the agent's fitness value. The classifier system has been tested with well-known medical data sets from the UCI machine learning database, showing superior performance to other methods such as the nearest neighbor, decision tree, and neural networks.

  • PDF

Design and Evaluation of an Agent-based Intelligent System Modeling Architecture for Cockpit Agenda Management (항공시스템 아젠다 관리를 위한 에이젼트 모델의 설계 및 평가)

  • Cha, Woo-Chang
    • Journal of KIISE:Software and Applications
    • /
    • v.27 no.6
    • /
    • pp.642-650
    • /
    • 2000
  • The pilot (human actor) involved in the control loop of the highly automated aircraft systems (machine actor) must be able to monitor these systems just as the machine actor must also be able to monitor the human actor. For its safety and better performance of the human machine system, each of the two elements must be knowledgeable about the other's intentions or goals. In fact, several recent accidents occurred due to goal conflicts between human and machines in a modern avionic system. To facilitate the coordination of these actors, a computational aid was developed. The aid, which operates in a part-task simulator environment, attempts to facilitate the management of the goals and functions being performed to accomplish them. To provide an accurate knowledge of both actors' goals and their function statuses, the aid uses agent-based objects representing the elements of the cockpit operations. This paper describes the development of the flightdeck goals and functions called Agenda Management.

  • PDF

Balanced Clustering based on Mobile Agents for the Ubiquitous Healthcare Systems (유비쿼터스 헬스케어 시스템에서 이동에이전트 기반 균형화 클러스터링)

  • Mateo, Romeo Mark A.;Lee, Jae-Wan;Lee, Mal-Rey
    • Journal of Internet Computing and Services
    • /
    • v.11 no.3
    • /
    • pp.65-74
    • /
    • 2010
  • In the ubiquitous healthcare, automated diagnosis is commonly achieved by an agent system to provide intelligent decision support and fast diagnosis result. Mobile agent technology is used for efficient load distribution by migrating processes to a less loaded node which is considered in our design of a ubiquitous healthcare system. This paper presents a framework for ubiquitous healthcare technologies which mainly focuses on mobile agents that serve the on-demand processes of an automated diagnosis support system. Considering the efficient utilization of resources, a balanced clustering for the load distribution of processes within nodes is proposed. The proposed algorithm selects overloaded nodes to migrate processes to near nodes until the load variance of the system is minimized. Our proposed balanced clustering efficiently distributes processes to all nodes considering message overheads by performing the migration to the near nodes.

A Method for Information Source Selection using Teasaurus for Distributed Information Retrieval

  • Goto, Shoji;Ozono, Tadachika;Shintani, Toramatsu
    • Proceedings of the Korea Inteligent Information System Society Conference
    • /
    • 2001.01a
    • /
    • pp.272-277
    • /
    • 2001
  • In this paper, we describe a new method for selecting information sources in a distributed environment. Recently, there has been much research on distributed information retrieval, that is information retrieval (IR) based on a multi-database model in which the existence of multiple sources is modeled explicitly. In distributed IR, a method is needed that would enable selecting appropriate sources for users\` queries. Most existing methods use statistical data such as document frequency. These methods may select inappropriate ate sources if a query contains polysemous words. In this paper, we describe an information-source selection method using two types of thesaurus. One is a thesaurus automatically constructed from documents in a source. The other is a hand-crafted general-purpose thesaurus(e.g. WordNet). Terms used in documents in a source differ from one another and the meanings of a term differ depending on th situation in which the term is used. The difference is a characteristic of the source. In our method, the meanings of a term are distinguished between by the relationship between the term and other terms, and the relationship appear in the co-occurrence-based thesaurus. In this paper, we describe an algorithm for evaluating a usefulness of a source for a query based on a thesaurus. For a practical application of our method, we have developed Papits, a multi-agent-based in formation sharing system. An experiment of selection shows that our method is effective for selecting appropriate sources.

  • PDF

MultiHammer: A Virtual Auction System based on Information Agents

  • Yamada, Ryota;Hattori, Hiromitsy;Ito, Takayuki;Ozono, Tadachika;Chintani, Toramastsu
    • Proceedings of the Korea Inteligent Information System Society Conference
    • /
    • 2001.01a
    • /
    • pp.73-77
    • /
    • 2001
  • In this paper, we propose a virtual action system based on information agents, We call the system the MultiHammer, MultiHammer can be used for studying and analyzing online actions. MuiltiHammer provides functions of implement-ing a meta online action site and an experiment environ-ment. We have been using MultiHammer as an experiment as an experiment environment for BiddinBot. BiddingBot aims at assisting users to bid simultaneously in multiple online auctions. In order to bid simultaneously in multiple online auctions. In order to analyze the behavior of BiddngBot, we need to pur-chase a lot of items. It is hard for us to prepare a lot of fund to show usability and advantage of BiddingBot. MultiHam-mer enables us to effectively analyze the behavior of BiddingBot. MultiHammer consists of three types of agents for information collecting data storing and auctioning. Agents for information wrappers. To make agent work as wrarp-pers, we heed to realize software modules for each online action site. Implementing these modules reguires a lot of time and patience. To address this problem, we designed a support mechanism for developing the modules. Agents for data storing record the data gathered by agents for informa-tion collecting. Agents for auctioning provide online services using data recorded by agents for data storing. By recording the activities in auction sites. MultiHammer can recreate any situation and trace auction for experimentation, Users can participate in virtual using the same information in real online auctions. Users also participate in real auc-tions via wrapper agents for information collecting

  • PDF

A New Dynamic Auction Mechanism in the Supply Chain: N-Bilateral Optimized Combinatorial Auction (N-BOCA) (공급사슬에서의 새로운 동적 경매 메커니즘: 다자간 최적화 조합경매 모형)

  • Choi Jin-Ho;Chang Yong-Sik;Han In-Goo
    • Journal of Intelligence and Information Systems
    • /
    • v.12 no.1
    • /
    • pp.139-161
    • /
    • 2006
  • In this paper, we introduce a new combinatorial auction mechanism - N-Bilateral Optimized Combinatorial Auction (N-BOCA). N-BOCA is a flexible iterative combinatorial auction model that offers optimized trading for multi-suppliers and multi-purchasers in the supply chain. We design the N-BOCA system from the perspectives of architecture, protocol, and trading strategy. Under the given N-BOCA architecture and protocol, auctioneers and bidders have diverse decision strategies f3r winner determination. This needs flexible modeling environments. Hence, we propose an optimization modeling agent for bid and auctioneer selection. The agent has the capability to automatic model formulation for Integer Programming modeling. Finally, we show the viability of N-BOCA through prototype and experiments. The results say both higher allocation efficiency and effectiveness compared with 1-to-N general combinatorial auction mechanisms.

  • PDF