MODEL modeling object attributes

Chapter 2, Static Models Object Attributes and Invariants, describes how attributes abstract variations in the implementation of object state. Chapter 3, Behavior Models Object Types and Operations, describes how operation specifications describe externally visible behavior of an object, independently of algorithmic and representation decisions. 

The static part deals with the information we have about the state of an object at ary given moment. At a given level of time granularity, we describe static attributes, relationships, and constraints between objects. Chapter 2, Static Models Object Attributes and Invariants, is about modeling static aspects using abstract attributes. 

Chapter 2 Static Models Object Attributes and Invariants... 

Modeling Object State Types, Attributes, and Associations... 

Specifications describe how a client can use a component. What we really want to say about a component is what it does its behavior, or the actions it takes part in. We have seen how to specify the externally visible behavior of a type by specifying actions in terms of a type model of attributes. Because the component doesn t necessarily have to be implemented along the same lines as its model, the implementation need not explicitly represent distinct objects that belong to the types used within that model. Those types are used to structure the static model and relate it to the business. 

A collaboration is a set of related actions between typed objects playing certain roles with respect to others in the collaboration, within a common model of attributes. The actions are grouped into a collaboration so as to indicate that they serve a common purpose. Typically, the actions are used in different combinations to achieve different goals or to maintain an invariant between the participants. Each role is a place for an object and is named relative to the other roles in the overall collaboration. 

On a larger scale, more-complex models can be used to represent the types of whole systems or components and are usually shown pictorially. In an abstract model, the attributes and their types are chosen to help specify the operations on the component as a whole and, according to good object-oriented analysis practice, are based on a model of the domain. However, anyone who has been involved in practical OOD is aware that the design phase introduces all sorts of extra classes as patterns are applied to help generalize the design, make it more efficient, distribute the design, provide persistence or a GUI, and so on. But we can still retrieve the abstract model from any tme implementation in the same way as for the simpler models. 

One last step is to decide who can see whom—in other words, object attributes—and we append arrowheads to the links in our model. The simple criterion here is that any object needs a state corresponding to a link to every other objects that it must remember across its operations. Again, these links need not correspond to stored pointers in program code they can themselves be abstractions subject to further refinement. 

These frameworks must now be mapped to our problem domain and must be related to one another by shared objects, attributes, and so on. Figure 11.10 shows the overall problem model as an application of these frameworks. Of course, these frameworks must inter-... 

The processors in a physical model can be modeled as objects, their states modeled as attributes, their capabilities modeled as attributes, and communication links shown as explicit objects. It is useful to make visual distinctions between categories using stereotypes or a distinguished notation such as the one UML provides or, you can use traditional network diagram symbols for the different hardware objects. Base operating systems can be shown as part of this hardware architecture (see Figure 12.1). 

We are uncomfortable with the treatment of use cases as objects and have found much confusion among practitioners about what this means. Just because there are commonality and variation across use cases does not mean that they should be modeled as objects to do so confuses the separation of actions (interactions that cause changes of state) and attributes (the states that affect, and are affected by, actions). In Catalysis, what is modeled as an action at one level of abstraction (for example, buy product) can easily be reified into a model object in a refinement (for example, place order and deliver and pay actions revolving around an order model object). 

Specification mappings, described by the following sbc semantic relationships, are used to specify the value of attributes of various modeling elements. They express, (a) binary relations, such as whole/ part links, (b) communication lines among modeling objects, or (c) the value of simple describing properties. 

Line 1 indicates that the definition of Kg, depends on the following four modeling objects (Kaj-operator), reaction-centers) (see line 3) with each element of the list defined as an instance of the basic modeling element, atom. 

Fig. 4. Select attributes of the modeling objects, notle, and flow-opening-description.

It is responsible not only for accessing the data that have to ie integrated but also for storing all integration documents as well as all integration rules inside the Comos PT system. To allow other parts of Comos PT to use these data, they cannot be simply stored as BLOB inside the Comos PT database. Instead, they are saved as Comos PT objects, exploiting the possibilities of the Comos PT data model, like attributes and references. 

Variable subset selection is performed by GAs, optimising populations of models according to a defined objective function related to model quality. In partial ranking models objective function is an expression of the degree of agreement between the element ranking resulting from experimental attributes and that provided by the selected subset of model attributes. 

Starting at the top, the assembly data object has one-to-many type of relationship with the part data object, whilst part object has one-to-one type of relationship with the assembly object. This determines the schema for the assembly objeet and bill of materials (BOM) is an example of it. The part object has one-to-one type of relationship with the task sequence object and it is the same viee versa. In practical terms this means that there is always a unique sequenee of tasks to manufacture the part dictated by the material and volume involved. The task sequence object has one-to-many type of relationship with the task object and the task object has a one-to-one type of relationship with the task sequence. This means that a task sequence often contains many different types of tasks. Finally, the task object has one-to-many type of relationship with the material object and equipment object, whilst the material and the equipment objects have a one-to-one type of relationship with the task object In practical terms this means that a task often utihses many different types of materials and equipment to make the parts. The determination of these relationships together with the object attributes lead us to the schema design that can hold all the information required for the manufacturing process design. The data relationships model of Fig. 3.2 integrates the key variables involved and their interactions... 

Aspects of object system, model-yield, attributes, K Pis... 

In this paper a strategy for complex system modeling is presented in which the objective of the analysis and associated attributes are reflected by the model. Said attributes indicate the type of analysis required, the type of loading and boundary conditions, the type of geometry and the environment for the analysis, including the hardware, software and time frame resources. As an example, a model of a flexible internal combustion engine system based on the "Stiller-Smith Mechanism" is presented, in which a combination of solid, beam, and gap elements are used to represent the entire, 3-D system. The models presented are use to produce elastodynamic response needed for system design purposes. 

The characteristic of a relational database model is the organization of data in different tables that have relationships with each other. A table is a two-dimensional consti uction of rows and columns. All the entries in one column have an equivalent meaning (c.g., name, molecular weight, etc. and represent a particular attribute of the objects (records) of the table (file) (Figure 5-9). The sequence of rows and columns in the tabic is irrelevant. Different tables (e.g., different objects with different attributes) in the same database can be related through at least one common attribute. Thus, it is possible to relate objects within tables indirectly by using a key. The range of values of an attribute is called the domain, which is defined by constraints. Schemas define and store the metadata of the database and the tables. 

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