Inheritance for software reuse: The good, the bad, and the ugly

Inheritance is a powerful mechanism supported by object-oriented programming languages to facilitate modifications and extensions of reusable software components. This paper presents a taxonomy of the various purposes for which an inheritance mechanism can be used. While some uses of inheritance significantly enhance software reuse, some others are not as useful and in fact, may even be detrimental to reuse. The paper discusses several examples, and argues for a programming language design that is selective in its support for inheritance

Generalized synchronization: a modified system approach

The universal mechanism resulting in the generalized synchronization regime arising in the chaotic oscillators with the dissipative coupling has been described. The reasons of the generalized synchronization occurrence may be clarified by means of a modified system approach. The main results are illustrated by unidirectionally coupled Rossler systems, Rossler and Lorenz systems and logistic maps.Comment: 4 pages, 2 figure

Social Structure, Social Organization and Theme in Sangam Literature

This article explains the changes that took place in society, community and in epithet structures based on Sangam literature. And how the society is shaped by the changes seen in internal and external life. It also explains the changes that occurred due to the development level of the social systems, what are those development levels and about the life style of Sangam people. Overall, the article clearly explores the life style, family structure, social structures and social organization of the Sangam people

Observation of chaotic beats in a driven memristive Chua's circuit

In this paper, a time varying resistive circuit realising the action of an active three segment piecewise linear flux controlled memristor is proposed. Using this as the nonlinearity, a driven Chua's circuit is implemented. The phenomenon of chaotic beats in this circuit is observed for a suitable choice of parameters. The memristor acts as a chaotically time varying resistor (CTVR), switching between a less conductive OFF state and a more conductive ON state. This chaotic switching is governed by the dynamics of the driven Chua's circuit of which the memristor is an integral part. The occurrence of beats is essentially due to the interaction of the memristor aided self oscillations of the circuit and the external driving sinusoidal forcing. Upon slight tuning/detuning of the frequencies of the memristor switching and that of the external force, constructive and destructive interferences occur leading to revivals and collapses in amplitudes of the circuit variables, which we refer as chaotic beats. Numerical simulations and Multisim modelling as well as statistical analyses have been carried out to observe as well as to understand and verify the mechanism leading to chaotic beats.Comment: 30 pages, 16 figures; Submitted to IJB

Community, Society, and Religion in Sangam Literature

The life of the Sangam age is divided into Akam and Puram. It developed intrinsic virtues among the people of the Sangam age. The social formation is an improved form of creation from earlier narrow relationships. The social formation of the Sangam age is based on the Sangam age alone. The fundamentals of society, its peculiarities, and the changes that took place from the Sangam period to the present day are explained here. The Sangam society divides family life into ‘secret love’ and ‘chastity,’ and the Sangam songs speak of the worldly life of ‘secret love’ and ‘chastity’ between the leader and the leader

Dynamical Evolution of Globular Clusters in Hierarchical Cosmology

We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical models of galaxy formation. These clouds are enriched with heavy elements from earlier stars and could produce star clusters in a similar way to nearby molecular clouds. The masses and sizes of the model clusters are in excellent agreement with the observations of young massive clusters. Do these model clusters evolve into globular clusters that we see in our and external galaxies? In order to study their dynamical evolution, we calculate the orbits of model clusters using the outputs of the cosmological simulation of a Milky Way-sized galaxy. We find that at present the orbits are isotropic in the inner 50 kpc of the Galaxy and preferentially radial at larger distances. All clusters located outside 10 kpc from the center formed in the now-disrupted satellite galaxies. The spatial distribution of model clusters is spheroidal, with a power-law density profile consistent with observations. The combination of two-body scattering, tidal shocks, and stellar evolution results in the evolution of the cluster mass function from an initial power law to the observed log-normal distribution.Comment: 5 pages, proceedings of IAU 246 "Dynamical Evolution of Dense Stellar Systems", eds. Vesperini, Giersz, Sill

Collision-free motion of two robot arms in a common workspace

Collision-free motion of two robot arms in a common workspace is investigated. A collision-free motion is obtained by detecting collisions along the preplanned trajectories using a sphere model for the wrist of each robot and then modifying the paths and/or trajectories of one or both robots to avoid the collision. Detecting and avoiding collisions are based on the premise that: preplanned trajectories of the robots follow a straight line; collisions are restricted to between the wrists of the two robots (which corresponds to the upper three links of PUMA manipulators); and collisions never occur between the beginning points or end points on the straight line paths. The collision detection algorithm is described and some approaches to collision avoidance are discussed

Seismic Lateral Earth Pressures on Retaining Structures

Various methods are available to estimate seismic earth pressures on soil retaining structures which cane be grouped to experimental, analytical and numerical methods. 1G model shaking table studies or high-g level centrifuge model shaking studies give some insight on the variation of seismic earth pressures along height of the retaining structure. In the simple analytical methods, M-O method based pseudo-static analysis is extensively used to evaluate seismic earth pressure variation and its probable resultant location. Pseudodynamic analysis method based analyses are also developed and are in progress for the same. Besides, these experimental and analytical methods, FEM or FDM based numerical simulations of the retaining structures provide much information on the seismic lateral earth pressure variation. In this paper, the methods available and the procedures to be followed to determine the lateral seismic earth pressures and their recent developments are summarized. Numerical simulations of seismic behavior of cantilever retaining walls was performed using FLAC and the results obtained regarding seismic earth pressures are discussed

Deccan volcanism and K-T boundary signatures

The Deccan Traps in the Indian subcontinent represent one of the most extensive flood basalt provinces in the world. These basalts occur mainly as flat-lying, subaerially erupted tholeiitic lava flows, some of which are traceable for distances of more than 100 km. Offshore drilling and geophysical surveys indicate that a part of the Deccan subsided or was downfaulted to the west beneath the Arabian Sea. The presence of 1 to 5 m thick intertrappean sediments deposited by lakes and rivers indicates periods of quiescence between eruptions. The occurrence of numerous red bole beds among the flows suggests intense weathering of flow tops between eruptive intervals. Although the causative relationship of the Cretaceous-Tertiary (K-T) biotic extinctions to Deccan volcanism is debatable, the fact that the main Deccan eruptions straddle the K-T event appears beyond doubt from the recent Ar-40/Ar-39 ages of various Deccan flows. This temporal relationship of the K-T event with Deccan volcanism makes the petrochemical signatures of the entire Deccan sequence (basalt flows, intercalated intertrappean sediments, infratrappean Lameta beds (with dinosaur fossils), and the bole beds) pertinent to studies of the K-T event. The results of ongoing study is presented