Multiple Inheritance Hierarchies Research Articles

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The paper presents a unified model for testing tools for object-oriented application development. Based the available papers were identified shortcomings of existing work and identified the following optimal criteria, which shall comply the resulting model: 1. To deep inheritance hierarchies 2. To presents of multiple inheritance hierarchies 3. To presents of abstract classes in the hierarchy 4. To presents of multiple (n-ary) associations 5. To presents of associations with attributes 6. To presents of a composition between classes 7. To presents of recursive associations 8. To presents of associations between classes belonging to the same inheritance hierarchy 9. To presents of association classes 10. To presents between the association class and other classes 11 To presents enumerations in model With a unified graphical language UML class diagram unified model testing. The paper we verified compliance with the resulting implementation of the selected criteria was presented. Currentlythe implementation of applications using object-oriented programming languages and relational databases. To overcome the object-relational mismatch it is necessary to implement object-related mapping patterns presents. The paper presents three methods used to represent the class hierarchy highlighted the advantages and disadvantages of each method. For test the feasibility a unified model chosen development environment SharpArchitect RAD Studio which is designed object applications in C# and are implementing a relational database. The paper presents the developed object model in the form a class diagram showing the interfaces and inheritance relations diagram containing all the tables and columns the resulting database. In the conclusion recommendations on the areas for further development work and identified the need of implement a unified model with other approaches proposed by the authors was used.

Designing a New Assertion Constraints Model for Mobile Databases

In this paper a new assertion constraint model is proposed and implemented. The model is designed to enforce and maintain the integrity constraints in mobile database and object data model environments. It has an object assertion model for integrity constraints which it is used to create classes and collect attributes and their constraints that are derived from multiple composition or inheritance hierarchies. Also it has a compile-time model which keeps the derivation path along with the attributesâ?? relationships. Furthermore, the run-time model enforces integrity constraints, enforcing the logical integrity constraints during the run-time. And a new technique is designed to check the object metadata to detect the object violation before it occurs. However, the model is implemented and tested over set of definitions that check attribute values validity and objects for object-oriented and mobile databases.

Efficient dynamic dispatching with type slicing

A fundamental problem in the implementation of object-oriented languages is that of a frugal implementation of dynamic dispatching, that is, a small footprint data structure that supports quick response to runtime dispatching queries of the following format: which method should be executed in response to a certain message sent to a given object. Previous theoretical algorithms for this problem tend to be impractical due to their conceptual complexity and large hidden constants. In contrast, successful practical heuristics lack theoretical support. The contribution of this article is in a novel type slicing technique, which results in two dispatching schemes: TS and CT d . We make the case for these schemes both practically and theoretically. The empirical findings on a corpus of 35 hierarchies totaling some 64 thousand types from eight different languages, demonstrate improvement over previous results in terms of the space required for the representation, and the time required for computing it. The theoretical analysis is with respect to ι, the best possible compression factor of the dispatching matrix. The results are expressed as a function of a parameter κ, which can be thought of as a metric of the complexity of the topology of a multiple inheritance hierarchy. In single inheritance hierarchies κ = 1, but although κ can be in the order of the size of the hierarchy, it is typically a small constant in actual use of inheritance; in our corpus, the median value of κ is 5, while its average is 6.4. The TS scheme generalizes the famous interval containment technique to multiple inheritance. TS achieves a compression factor of ι/κ, that is, our generalization comes with an increase to the space requirement by a small factor of κ. The pay is in the dispatching time, which is no longer constant as in a naive matrix implementation, but logarithmic in the number of different method implementations. In practice, dispatching uses one indirect branch and, on average, only 2.5 binary branches. The CT schemes are a sequence of algorithms CT 1 , CT 2 , CT 3 , …, where CT d uses d memory dereferencing operations during dispatch, and achieves a compression factor of 1/ d ι 1−1/ d in a single inheritance setting. A generalization of these algorithms to a multiple inheritance setting, increases the space by a factor of (2κ) 1−1/ d . This trade-off represents the first bounds on the compression ratio of constant-time dispatching algorithms. We also present an incremental variant of the CT d suited for languages such as Java.

Encoding multiple inheritance hierarchies for lattice operations

Incremental updates to multiple inheritance hierarchies are becoming more prevalent with the increasing number of persistent applications supporting complex objects. Efficient computation of the lattice operations greatest lower bound (GLB), least upper bound (LUB), and subsumption is critical. Techniques for the compact encoding of a hierarchy are required that support the operations. One method is to plunge the given ordering into a Boolean lattice of binary words, and perform lattice operations via Boolean operators. An overview of the approach is given and several methods are examined and compared. A new method is proposed, based on the top–down encoding of Caseau but without the lattice completion requirement, which permits incremental updates to the hierarchy to add nodes at the leaves. The algorithm requires polynomial time and space for encoding, and supports efficient lattice computations in applications where the classes of objects are stored as codes. Experimental results illustrate its effectiveness, and an analysis is provided on the effect of the order of insertion on the encoding.

Encoding multiple inheritance hierarchies for lattice operations

Encoding multiple inheritance hierarchies for lattice operations

현대 독일어 제2형 분사의 형용사 전환에 대한 제약

This paper addresses the issue of constraints on the conversion of the participle II in German, proposing a constraint-based lexical semantic approach. I argue against the widely accepted syntactic view which is based on the dichotomous distinction of intransitive verbs, which has been advanced by the Unaccusative Hypothesis [Perlmutter (1978)]. Several arguments are also given against the semantic view which is based on some aspectual notions such as ''telicity'', ''transformativity'' or ''terminativity''. The crucial constraints on the conversion of the participle II in German, it is argued, is instead two lexical semantic entailments, movement with a definite change of location and affectedness. These and other lexical semantic entailments in the sense of Dowty (1991) are encoded into the multiple inheritance type hierarchy of qfpsoa. The proposal made in this paper is based on the multiple inheritance hierarchy which is envisaged in a recent framework of head-driven Phrase Structure Grammar. (Chungnam National University)

Mixed functional properties in English stylistic inversion

One of the controversial issues in English stylistic inversion (SI) construction (e.g., Into the room walked a woman) is the functional status of preverbal PP and postverbal NP. Based on the distributional parallels among the PP, NP, ordinary subject and topic, this paper proposes that the PP in SI has a dual function as a subject and topic, while the NP also has some subject properties that the PP does not have. These mixed functional properties of the PP and the 'double' subject properties of SI are analyzed in the theory of HPSG, especially with the versions recently developed by Sag 1997, Manning and Sag 1999 and Ginzburg and Sag 2001, which posit the notions of the multiple type inheritance hierarchy and dissociation between the argument and valence structures. This analysis claims that the SI construction needs to simultaneously satisfy two general, independent constraints, head-subject-phrase and head-filler-phrase, as well as the construction specific lexeme-level constraint. This view suggests that the English SI construction is an instance of peripheral phenomena whose construction specific constraints are inherited from more general core constraints.

Efficient subtyping tests with PQ-encoding

Subtyping test , i.e., determining whether one type is a subtype of another, are a frequent operation during the execution of object-oriented programs. The challenge is in encoding the hierarchy in a small space, while simulataneously making sure that subtyping tests have efficient implmentation. We present a new scheme for encoding multiple and single inheritance hierarchies, which, in the standardized hierarchies, reduces the footprint of all previsously published schemes. The scheme is called PQ-encoding after PQ-trees , a data structure previously used in graph theory for finding the orderings that satisfy a collection of constraints. In particular, we show that in the traditional object layout model, the extra memory requirement for single inheritance hierarchies is zero. In the PQ-encoding subtyping tests are constant time, and use only two comparisons. Other than PQ-trees, PQ-encoding uses several novel optimization techniques. These techniques are applicable also in improving the performance of otehr, previously published, encoding schemes.

Encoding of Multiple Inheritance Hierarchies and Partial Orders

Efficient implementation of type inclusion is an important feature of object oriented programming languages with multiple inheritance. The idea is to associate to each type a subset of a set S={1,...,k} such that type inclusion coincides with subset inclusion. Such an embedding of types into 2S (the lattice of all subsets of S) is called a bit‐vector encoding of the type hierarchy. In this paper, we show that most known bit‐vector encoding methods can be inserted on a general theoretical framework using graph coloration, namely the notion of a simple encoding. We use the word simple because all these methods are heuristics for the general bit‐vector encoding problem, known as the 2‐dimension problem. First we provide a correct algorithm for partial orders based on simple encoding, improving the algorithm of Krall, Vitek, and Horspool (1997). Second we show that finding an optimal simple encoding is an NP‐hard problem. We end with a discussion on some practical issues.

Type-based derivational morphology

Approaches to morphology typically account for regular, completely productive affixation, while ignoring subregular and semiproductive schemata. The alternative approach to derivational morphology presented here relates exceptions and subregularities to productive rules. It accounts for the contribution lexicalized words make to the rule and for the fact that not all new formations follow the 'rules'. It also captures linguistically relevant generalizations that cannot be expressed in other theories. The approach is formalized in terms of complex recursive schemata structured in a multiple inheritance hierarchy, without positing lexical rules or lexical entries for affixes. These schemata structure the existing lexicon, reducing redundancy, and at the same time serve as the basis for productive word formation. The approach handles zero-derivation and other nonconcatenative morphology straightforwardly.

Dynamic reasoning with qualified syllogisms

A qualified syllogism is a classical Aristotelean syllogism that has been “qualified” through the use of fuzzy quantifiers, likelihood modifiers, and usuality modifiers, e.g., “ Most birds can fly; Tweety is a bird; therefore, it is likely that Tweety can fly.” This paper introduces a formal logic Q of such syllogisms and shows how this may be employed in a system of nonmonotonic reasoning. In process are defined the notions of path logic and dynamic reasoning system (DRS). The former is an adaptation of the conventional formal system which explicitly portrays reasoning as an activity that takes place in time. The latter consists of a path logic together with a multiple-inheritance hierarchy. The hierarchy duplicates some of the information recorded in the path logic, but additionally provides an extralogical specificity relation. The system uses typed predicates to formally distinguish between properties and kinds of things. The effectiveness of the approach is demonstrated through analysis of several “puzzles” that have appeared previously in the literature, e.g., Tweety the Bird, Clyde the Elephant, and the Nixon Diamond. It is also outlined how the DRS framework accommodates other reasoning techniques—in particular, predicate circumscription, a “localized” version of default logic, a variant of nonmonotonic logic, and reason maintenance. Furthermore it is seen that the same framework accomodates a new formulation of the notion of unless. A concluding section discusses the relevance of these systems to the well-known frame problem.

A massively parallel knowledge-base server using a hypercube multiprocessor

In this paper we study the parallel implementation of a traditional frame based knowledge representation system for a general purpose massively parallel hypercube architecture (such as the Connection Machine CM-2). We show that, using a widely available parallel system (instead of a special purpose architecture), it is possible to provide multiple users with efficient shared access to a large scale knowledge-base. Parallel algorithms are presented for answering multiple inference, assert and retract queries on both single and multiple inheritance hierarchies. In addition to theoretical time complexity analysis, empirical results obtained from extensive testing of a prototype implementation are presented.

Efficient handling of multiple inheritance hierarchies

article Free Access Share on Efficient handling of multiple inheritance hierarchies Author: Yves Caseau View Profile Authors Info & Claims ACM SIGPLAN NoticesVolume 28Issue 10Oct. 1, 1993 pp 271–287https://doi.org/10.1145/167962.165905Online:01 October 1993Publication History 52citation731DownloadsMetricsTotal Citations52Total Downloads731Last 12 Months20Last 6 weeks3 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my Alerts New Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

Multiple Inheritance, a Structuring Mechanism for Data, Processes and Procedures

A motivation is given for the use of multiple inheritance as a general mechanism for data, processes and procedures, and an object oriented programming language that incorporates such an inheritance mechanism is outlined. Objects in this language combine the notions of abstract data structures and processes. Classes and procedures are organized in multiple inheritance hierarchies. The main contribution of this paper is the introduction of a coroutine-like strategy for combining multiple action parts of objects. Coincidence of named properties from different classes are treated by combining all versions of the property. The inheritance mechanism on procedures offers an elegant way of combining a number of inherited operations with the same name.