Multiple Inheritance Research Articles

EMOD2D—a program in C++ for finite difference modelling of magnetotelluric TM mode responses over 2D earth

A program, EMOD2D, in C++, is developed to compute the apparent resistivities of two-dimensional geological structures for magnetotelluric (MT) H-polarization case, using finite difference technique. Five C++ classes with member functions are designed to compute apparent resistivitiy values. The program utilizes object oriented programming features such as multiple inheritance, encapsulation to allow the user to easily deploy and modify the given classes. This program has been used to study the responses of various ore deposit models. This modelling study is relevant to: (i) search for mineral deposits underlying conductive or resistive overburden, (ii) understand the response pattern for the ore body with different depths and conductivities, and (iii) study the response pattern for the ore body when it is in contact and without contact with the overburden. The program is compiled on Borland C++.

Traits

Inheritance is well-known and accepted as a mechanism for reuse in object-oriented languages. Unfortunately, due to the coarse granularity of inheritance, it may be difficult to decompose an application into an optimal class hierarchy that maximizes software reuse. Existing schemes based on single inheritance, multiple inheritance, or mixins, all pose numerous problems for reuse. To overcome these problems we propose traits , pure units of reuse consisting only of methods. We develop a formal model of traits that establishes how traits can be composed, either to form other traits, or to form classes. We also outline an experimental validation in which we apply traits to refactor a nontrivial application into composable units.

Sonneborn and the cytoplasm.

IN the late 1930s when Tracy Sonneborn was in graduate school and just starting his work on the genetics of protozoa, classical studies on genetics were almost finished. The second edition of Principles of Genetics by E. W. Sinnott and L. C. Dunn (1932) that appeared in that period was quite sophisticated, containing a good account of chromosome theory, segregation ratios produced by complex gene interactions, chromosome and genetic maps, polyploidy, aneuploidy, multiple factor inheritance, sex determination, and evolution. The authors argued strongly that virtually all inheritance was ascribable to nuclear genes. Only Correns's work on plastid inheritance was cited as an example of cytoplasmic inheritance, and it was pointed out that this should be considered only a minor exception to the general rule that chromosomal genes determine the hereditary characters of the organism. Other biologists, particularly cell physiologists such as L. V. Heilbrunn at the University of Pennsylvania, were not so sure. They thought that classical genetics dealt only with superficial characters and that the fundamental characters of organisms such as membrane permeability, metabolism, etc., were controlled by the cytoplasm. It is not clear what Sonneborn thought of this controversy, but from what I know about Sonneborn, he must, at least, have had an open mind about the matter. All classical genetics was based on multicellular organisms, in which characters were seen after a complex developmental process. Once Sonneborn had discovered mating types in the protozoa it became possible to carry out classical genetic studies with the protozoa and study their inheritance without an intervening period of somatic development. Perhaps the genetics of single-cell organisms, the protozoa, would prove to be a bit different from the classical picture.

A new approach of clustering based machine-learning algorithm

Machine-learning research is to study and apply the computer modeling of learning processes in their multiple manifestations, which facilitate the development of intelligent system. In this paper, we have introduced a clustering based machine-learning algorithm called clustering algorithm system (CAS). The CAS algorithm is tested to evaluate its performance and find fruitful results. We have been presented some heuristics to facilitate machine-learning authors to boost up their research works. The InfoBase of the Ministry of Civil Services is used to analyze the CAS algorithm. The CAS algorithm is compared with other machine-learning algorithms like UNIMEM, COBWEB, and CLASSIT, and was found to have some strong points over them. The proposed algorithm combined advantages of two different approaches to machine learning. The first approach is learning from Examples, CAS supports Single and Multiple Inheritance and Exceptions. CAS also avoids probability assumptions which are well understood in concept formation. The second approach is learning by Observation. CAS applies a set of operators that have proven to be effective in conceptual clustering. We have shown how CAS builds and searches through a clusters hierarchy to incorporate or characterize an object.

Le concept reproducteur

What counts as epigenetic depends on what counts as genetic. It is argued that Weismannism, the doctrine of genetic continuity and somatic discontinuity, is the basis for an overly inclusive concept of epigenetics as every inherited resource << beyond the genes >>. An alternative theoretical perspective, the << reproducer >> concept, facilitates analysis of multiple inheritance systems without labeling all non-genetic inheritance << epigenetic >>.

The implementation of ada 2005 synchronized interfaces in the GNAT compiler

One of the most important object-oriented features of the new revision of the Ada Programming Language is the introduction of Abstract Interfaces to provide a form of multiple inheritance. Ada 2005 Abstract Interface Types are akin to Java interfaces, and as such support inheritance of specification rather than inheritance of implementation. Ada 2005 interfaces apply as well to tasks and protected types, and provide a classification mechanism for concurrent programming that goes considerably beyond the capabilities of Java.This paper summarizes the implementation in the GNAT compiler of the various kinds of interfaces that relate to concurrent programming in Ada 2005 [1]. The implementation is efficient, and involves mostly modifications to the compiler front-end, with virtually minimal impact on run-time structures, beyond those that are in place to support regular interfaces. However, the implementation of interface operations as triggers in selective waits and asynchronous transfers of control proved to be surprisingly delicate and requires additional predefined primitive operations.

Relationship Structures and Semantic Type Assignments of the UMLS Enriched Semantic Network

ObjectiveThe Enriched Semantic Network (ESN) was introduced as an extension of the Unified Medical Language System (UMLS) Semantic Network (SN). Its multiple subsumption configuration and concomitant multiple inheritance make the ESN's relationship structures and semantic type assignments different from those of the SN. A technique for deriving the relationship structures of the ESN's semantic types and an automated technique for deriving the ESN's semantic type assignments from those of the SN are presented. DesignThe technique to derive the ESN's relationship structures finds all newly inherited relationships in the ESN. All such relationships are audited for semantic validity, and the blocking mechanism is used to block invalid relationships. The mapping technique to derive the ESN's semantic type assignments uses current SN semantic type assignments and preserves nonredundant categorizations, while preventing new redundant categorizations. ResultsAmong the 426 newly inherited relationships, 326 are deemed valid. Seven blockings are applied to avoid inheritance of the 100 invalid relationships. Sixteen semantic types have different relationship structures in the ESN as compared to those in the SN. The mapping of semantic type assignments from the SN to the ESN avoids the generation of 26,950 redundant categorizations. The resulting ESN contains 138 semantic types, 149 IS-A links, 7,303 relationships, and 1,013,876 semantic type assignments. ConclusionThe ESN's multiple inheritance provides more complete relationship structures than in the SN. The ESN's semantic type assignments avoid the existing redundant categorizations appearing in the SN and prevent new ones that might arise due to multiple parents. Compared to the SN, the ESN provides a more accurate unifying semantic abstraction of the UMLS Metathesaurus.

Subtext

Representing programs as text strings makes programming harder then it has to be. The source text of a program is far removed from its behavior. Bridging this conceptual gulf is what makes programming so inhumanly difficult -- we are not compilers. Subtext is a new medium in which the representation of a program is the same thing as its execution. Like a spreadsheet, a program is visible and alive, constantly executing even as it is edited. Program edits are coherent semantic transformations.The essence of this new medium is copying. Programs are constructed by copying and executed by copy flow : the projection of changes through copies. The simple idea of copying develops into a rich theory of higher-order continual copying of trees . Notably absent are symbolic names, the workhorse of textual notation, replaced by immediately-bound explicit relationships. Subtext unifies traditionally distinct programming tools and concepts, and enables some novel ones. Ancestral structures are a new primitive data type that combines the features of lists and records, along with unproblematic multiple inheritance. Adaptive conditionals use first-class program edits to dynamically adapt behavior.A prototype implementation shows promise, but calls for much further research. Subtext suggests that we can make programming radically easier, if we are willing to be radical.

Raffinement de classes dans les langages à objets statiquement typés

Classes and specialisation bring simultaneously structure and flexibility to object oriented programs. However, many propositions for model extension (aspects, modules, etc.) prove that these qualities are often considered insufficient. This article proposes two binded notions of class refinement and modules, the former improves flexibility whereas the latter improves structure. Modules contain a coherent set of class definitions and can modify classes defined in modules they depend. This proposition focuses on statically typed languages where modules can be separately compiled. It is based on a module metamodel analogue to the class one and problems with multiple specialisation and refinement are managed like those in multiple inheritance.

The Theory of Classification Part 17: Multiple Inheritance and the Resolution of Inheritance Conflicts.

The author considers the theoretical issues raised by combining multiple implementations. Then, he considers what it means for an object to belong to multiple parent classes, defining the notion of multiple classification.

Familial recurrence rates and genetic models of multiple sclerosis

Susceptibility to multiple sclerosis (MS) is determined by both inherited and non-inherited factors. The importance of genetic factors is demonstrated by the increased risk of disease in relatives of MS patients. Our objective was to determine the implications of the observed familial recurrence risks for the genetic basis of MS. We developed a computer program which calculates recurrence risks for monozygotic (MZ) twins, siblings, and second degree relatives, and used it to calculate recurrence risks for a wide variety of genetic models. We investigated models with different numbers of genes, different patterns of interaction between the genes, and dominant or recessive inheritance. The models that best reproduced the observed values had multiple loci with strongly synergistic interaction and autosomal dominant (AD) inheritance. At least six loci were required, and we found no upper limit on the number of loci. Models with genetic heterogeneity, where only a fraction of the risk loci are required for disease, are possible. In models with large numbers of loci the "abnormal" alleles conferring risk of disease are the most common allele. We conclude that a variety of genetic models with multiple genes, dominant inheritance, and synergistic interaction between risk genes are consistent with the observed familial recurrence rates in MS.

Algon: From Interchangeable Distributed Algorithms to Interchangeable Middleware

We present the design and implementation of a framework for interchangeable distributed algorithms. The algorithms are drawn from the set which includes mutual exclusion, deadlock detection and agreement protocols, and we have implemented several examples of the first tonsiswo of these. Algon cts of a library of algorithms, a framework for incorporating them into a new or existing system, and a tool for evaluating comparative performance. In this way, much of the complexity related to distributed systems can be isolated in its own component level and the programmer can choose from among different algorithms in the same class based on performance in a given application. Incorporating many algorithms in a single framework was made possible by the observation that algorithms in a given class, e.g. mutual exclusion, almost always expose the same methods. These methods interface with an Algon scheduler which maintains state and provides convenient hooks for the application to invoke the services of the algorithm.In this paper we describe the structure of Algon in detail, with a distributed deadlock detection algorithm as the case study. We then extend the notion of separation of concerns by creating an addition layer in Algon, underneath which the middleware that runs on each node can be interchanged, for example from Java-RMI to CORBA. Challenges in the re-tooling of the system, related to multiple inheritance, exceptions and the automatic generation of stubs and skeletons in our implementation language, Java, were overcome in novel ways. Algon has the potential to be a framework with a long life, as it can adapt to new middleware, such as .NET.

From Replicators to Heritably Varying Phenotypic Traits: The Extended Phenotype Revisited

It may seem somewhat odd to write about a book that was published 21 years ago, and when Kim Sterelny first suggested that I review again Dawkins’ Extended Phenotype I was dubious. It has been a very influential book, and although not as widely read as The Selfish Gene, it has had, I think, as great an impact on biologists’ work as its older sibling. Many reviews of the book have been written, and many scholars have referred to this book directly and indirectly. The point of view advocated in it – and it was, as Dawkins asserted at the very beginning of the book, openly a work of advocacy – has become mainstream among evolutionary theorists. There has been, as Dawkins hoped, a shift in perspective from the organism to the replicator as a unit of selection, and we are living in an intellectual atmosphere that is dominated by genetic and cultural replicators. Although this dominance has been challenged many times, it is today the most influential approach to evolution. Revisiting the book is therefore a daunting task, but it is also something that may be timely, for new ideas and new discoveries have emerged during the last 20 years, and some arguments have acquired a new significance (or insignificance). It is quite impossible to cover all the ground discussed in The Extended Phenotype, but it is possible to scrutinize the central idea – the superiority of the replicator-oriented perspective and its implications. I shall first examine the basis for choosing the single gene variant as the fundamental unit of genetic selection, and show the problems that this approach creates. I shall then argue that a perspective that focuses on multiple inheritance systems and heritably varying phenotypic traits allows a better understanding of evolutionary processes, including aspects relating to the extended phenotype, and provides a more general evolutionary perspective than a replicator-centered view.

Safe metaclass composition using mixin-based inheritance

In the context of meta-programming and reflective languages, classes are treated as full-fledged objects which are instances of other classes named metaclasses. Metaclasses have proved to be useful for defining new class properties. Examples of such properties are lazy memory allocation, multiple inheritance, having a single instance. A class with some property is obtained by instantiating a metaclass which implements the desired property. However, instantiation allows assigning to a class only properties defined by a single metaclass. A composition mechanism is needed to reuse properties defined by different metaclasses and assign them to a given class. This composition should be performed without breaking class-metaclass compatibility. The compatibility issue arises when a class is coupled to its metaclass. So, when composing metaclasses, we need to take care of such coupling to avoid run-time exceptions. In this paper, we explore the use of mixin-based inheritance to perform metaclass composition. Mixin-based inheritance is an interesting alternative to both single and multiple inheritance. As opposite to single inheritance, it allows reusing code among different class hierarchies. Contrary to multiple inheritance, it allows developers to explicitly specify the desired behavior through explicit linearizations. Our proposal is to define and compose reusable class properties by introducing mixins at the metaclass level. We demonstrate that this introduction can be done efficiently without altering compatibility.

The Hindu Succession act: One Law, Plural Identities

A broad definition of law manifests itself in various ways: it legitimates certain visions of social order, it determines relations between individuals and groups, and it manipulates cultural understandings and discourses over various concepts of rights - and duties. In India, the Hindu Succession Rights Act (HSA) of 1956 allows the wife and daughters, along with the sons of the deceased senior male, to claim an equal share in familial property. By giving inheritance rights to daughters and widows, not only to sons, this Act proposes a radically different organization of the ideal household, commonly referred to as the ‘Indian joint family’. The Act initiates a transformation of Hindu women’s status through their rights to property, which implies the transformation of women’s rights and duties in India. It also affects men’s access to natal property and modifies brother-sister relationships. Moreover, it redefines some religious categories. Firstly, under this Act the category ‘Hindu’ includes Hindu, Buddhist, Jain or Sikh. Secondly, it regulates the multiple religious and inheritance practices that still exist in different parts of India.Like other national laws concerning the personal rights of the Hindu population, the HSA is the result of a compromise between different legal traditions such as various Hindu schools of law, British common law and the western philosophy underlying the concept of equality. The long debate over personal laws that took place in the 1950s led Indian legislators to envisage a new ‘social order’ in their laws, which would become potential agents of social change. But such legislative initiatives are not sufficient because their success depends on tribunals’ reactions and their capacity and desire to elaborate a new jurisprudence. In addition, innovative legal cases depend on people’s knowledge of the law and their desire to use it instead of other forms of conflict resolution. Drawing on observations made during an extensive fieldwork period in a rural community and case studies in Pune tribunals, this paper shows that women know that they have some rights to their fathers’ and husbands’ property. However, for various reasons, they do not see any advantage in claiming those rights. Women often find it difficult to reconcile claiming rights with their duties as daughters or daughters-in-law and the social restrictions associated with widowhood. This socio-legal ethnography of women’s succession rights in the state of Maharashtra contributes to the understanding of the dynamics of social cohesion in an environment where legal pluralism offers plural sources of identity definition and transformation.

Diamond Inheritance and Attribute Types in Timor.

In Timor multiple inheritance of methods from a common abstract ancestor (e.g. Collection) and of separate parts (possibly repeatedly) from distinct supertypes (e.g. a Radio, a Cassette Player) are handled in different ways. The paper shows that neither technique is suitable for cases where a common concrete ancestor (e.g. Person) is specialised in different subtypes (e.g. as a Student, an Employee) and then brought together in a new subtype, possibly with repeated inheritance (e.g. a Doubly Employed Student). For such cases a new kind of type (attribute types) is proposed, which provides an alternative programming paradigm to inheritance, based on the idea of adjectives and their use in noun phrases in natural languages.

Inheriting Multiple and Repeated Parts in Timor.

The paper describes one aspect of multiple inheritance in the Timor programming language, viz. how parts such as a type Radio and a type Cassette Player can be inherited, where appropriate repeatedly, in subtypes such as a Radio Double Cassette Player. Because such types can also be defined via aggregation the paper begins by comparing inheritance with aggregation. It then shows how such cases can be handled first at the type level and then at the implementation level in Timor.

A simple and powerful type system for programming languages

A type system serves to guarantee that programs mix data of distinct types only as allowed by programmer declared rules. For example, a function declaration corresponds to one of these rules, providing a way to mix data of distinct types, possibly producing data of another type as a result. A type system also discovers the type of each (sub)expression throughout a program. This paper introduces a type system where types are parts of speech, and all relations among types are represented by a grammar, a grammar whose rules are written in terms of the types. In order to resolve types, i.e., discover which type each (sub)expression is, the type grammar may be used to parse a given program, as a second pass. A brief, Polish postfix programming language rich in types is presented, called the type grammar, as well as a way to translate down from a more natural syntax. We show how to extend the type grammar with new rules based on program declarations. By parsing with this postfix type grammar, unrestricted overloading (more powerful than Java’s) and unrestricted programmer-defined coercions (in some ways more powerful than multiple inheritance) may be implemented and understood in a straightforward manner. To realize these, a powerful parser like Earley’s efficient context-free parser, or others, which tolerate ambiguity efficiently, are required. We conclude by showing how a pair of coercions, in a cycle, proves useful.

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