自动化立体车库管理系统的研究(英文文献+CAD图纸)
confirms the information about the unassigned controllers from the NTA before cloning agents.When a fractal changes the information about the unassigned controllers, it must notify other fractals so that they can update their information.
 2.3. Agent modeling with UML
To make system architecture manageable and understandable, the artifacts of a system-intensive process can be expressed, specified, visualized, constructed, and documented. In recent years, a unified modeling language has emerged from earlier methods for analysis and design of object-oriented (OO) systems. In 1997, UML became recognized and accepted as a potential notation standard by Object Management Group (OMG) for modeling multiple perspectives of various systems [23]. UML is a simple, expressive, extensible, and visual modeling language [24]. UML is based on the object-oriented paradigm, and enables the extraction of architecturally significant elements of a model with respect to different viewpoints, independent of the system’s scale. It is mainly used to develop control software because many UML tools support the automatic generation of programming code from UML models. In this paper, modeling of the FrMS with UML is based on the implementation of an agent-based system.
2.3.1. Why UML?
UML provides several advantageous features for modeling a system [25]. First, it enables modeling of systems using OO concepts because its semantics come from Booch, object modeling technique (OMT), and object-oriented software engineering (OOSE). In particular, the use of a ‘‘package’’supporting OO concepts allows users to refine models iteratively. Second, it uni?es several modeling perspectives, enabling modeling of different kinds of systems (business versus software) and different development phases (requirements analysis, design, and implementation). Various kinds of models from different perspectives can be easily managed with one ?le. Third, many UML tools automatically generate skeleton source code from a model. For example, Rational RoseTM supports code generation in C/Ctt, Visual Basic, Java/J2EE, Ada 83/95. It also supports eXtensible Markup Language_Data Type  Definition (XML_DTD) and Common Object Request Broker Architecture (CORBA). Fourth, UML supports the use of a formal constraint language called Object Constraint Language (OCL) to specify constraints and other expressions attached to the models. OCL is a formal language that remains easy to read and write for adding unambiguous constraints to a model. The last advantage of UML is that it supports Model Driven Architecture (MDA) which is accepted as a standard by OMG. MDA addresses the complete life cycle of designing, deploying, integrating, and managing applications as well as data using open standards. It also provides an open, vendor-neutral approach to the challenge of interoperability. 2.3.2. UML models for an FrMS and agents
The fractal agents are modeled by using a class diagram as shown in Fig. 3. A class diagram describes the types of objects that are used within an objectoriented system, and de?nes the types of relationships between them. Attributes and operations of each class are used to de?ne the types of objects and the constraints between them. Four types of relationships available in the class model of UML are association, aggregation, generalization, and dependency (instantiates). The class diagram in Fig. 3 uses only associations (uni- and bi-directional) and dependency. An association relationship, the most general relationship, provides a pathway for the communication between model components including a class and an interface. A dependency is a relationship between two classes in which a change to one class will affect the other class. Stereotypes are usually used in UML models for representing the sub-classification of model elements. In addition to the predefined stereotypes, users can define customized stereotypes. Some classes in Fig. 3 have a stereotype called an entity, which is represented as an icon (circle with underbar). Also, some other stereotypes are used such as uses, creates, and supports and so on for the clari?cation of the associations between the classes. Additionally, multiplicity values are

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