Flow structure and scour around circular compound bridge piers – A review

Large amount of literature is presently available on the topic of scour around uniform piers and its control. However, relatively fewer studies have been carried out so far on the topic of flow field and scour around compound piers. The state of art on the topic of flow structure and scour around circular compound piers is presented herein. The available literature reveals that variations in foundation and pier geometry significantly affect the maximum depth of scour and its temporal variation. In case of compound piers the scour depth is highly sensitive to the change in elevation of the top surface of the foundation well. As compared to uniform piers, a reduction is observed in maximum depth of scour around compound pier when the top surface of the well is kept below the general level of river bed. These observations however are yet to be quantified. Results from an experimental study on flow field around the compound piers are also presented.     

Incorporating Ancestors' Influence in Genetic Algorithms

A new criterion of fitness evaluation for Genetic Algorithms is introduced where the fitness value of an individual is determined by considering its own fitness as well as those of its ancestors. Some guidelines for selecting the weighting coefficients for quantifying the importance to be given to the fitness of the individual and its ancestors are provided. This is done both heuristically and automatically under fixed and adaptive frameworks. The Schema Theorem corresponding to the proposed concept is derived. The effectiveness of this new methodology is demonstrated extensively on the problems of optimizing complex functions including a noisy one and selecting optimal neural network parameters.     

The OODB path-method generator (PMG) using access weights and precomputed access relevance

A path-method is used as a mechanism in object-oriented databases (OODBs) to retrieve or to update information relevant to one class that is not stored with that class but with some other class. A path-method is a method which traverses from one class through a chain of connections between classes and accesses information at another class. However, it is a difficult task for a casual user or even an application programmer to write path-methods to facilitate queries. This is because it might require comprehensive knowledge of many classes of the conceptual schema that are not directly involved in the query, and therefore may not even be included in a user's (incomplete) view about the contents of the database. We have developed a system, called path-method generator (PMG), which generates path-methods automatically according to a user's database-manipulating requests. The PMG offers the user one of the possible path-methods and the user verifies from his knowledge of the intended purpose of the request whether that path-method is the desired one. If the path method is rejected, then the user can utilize his now increased knowledge about the database to request (with additional parameters given) another offer from the PMG. The PMG is based on access weights attached to the connections between classes and precomputed access relevance between every pair of classes of the OODB. Specific rules for access weight assignment and algorithms for computing access relevance appeared in our previous papers [MGPF92, MGPF93, MGPF96]. In this paper, we present a variety of traversal algorithms based on access weights and precomputed access relevance. Experiments identify some of these algorithms as very successful in generating most desired path-methods. The PMG system utilizes these successful algorithms and is thus an efficient tool for aiding the user with the difficult task of querying and updating a large OODB. Received July 19, 1993 / Accepted May 16, 1997     

Enhanced thermal conductivity of nano-SiC dispersed water based nanofluid

Silicon carbide (SiC) nanoparticle dispersed water based nanofluids were prepared using up to 0·1?vol% of nanoparticles. Use of suitable stirring routine ensured uniformity and stability of dispersion. Thermal conductivity ratio of nanofluid measured using transient hot wire device shows a significant increase of up to 12% with only 0·1?vol% nanoparticles and inverse dependence of conductivity on particle size. Use of ceramic nanoparticles appears more appropriate to ensure stability of dispersion in nanofluid in closed loop single-phase heat transfer applications.     

Discrete two-time-scale systems

In this paper reduced-order modelling and control analysis of linear, discrete-time systems having dominant and non-dominant modes are presented. Decoupling of modes is achieved using an explicitly invertible linear transformation. A matrix norm condition is derived, the satisfaction of which enables approximate expressions for the block-diagonalizing matrices, eigenvalue distribution and state trajectories to be obtained. Design of stabilizing feedback controllers is developed and it is shown that two gain matrices are needed for separate assignment of dominant and non-dominant eigenvalues. The theoretical analysis is illustrated by control system examples.     

Mitotic Diversity in Homeostatic Human Interfollicular Epidermis

Despite decades of skin research, regulation of proliferation and homeostasis in human epidermis is still insufficiently understood. To address the role of mitoses in tissue regulation, we utilized human long-term skin equivalents and systematically assessed mitoses during early epidermal development and long-term epidermal regeneration. We now demonstrate four different orientations: (1) horizontal, i.e., parallel to the basement membrane (BM) and suggestive of symmetric divisions; (2) oblique with an angle of 45°–70°; or (3) perpendicular, suggestive of asymmetric division. In addition, we demonstrate a fourth substantial fraction of suprabasal mitoses, many of which are committed to differentiation (Keratin K10-positive). As verified also for normal human skin, this spatial mitotic organization is part of the regulatory program of human epidermal tissue homeostasis. As a potential marker for asymmetric division, we investigated for Numb and found that it was evenly spread in almost all undifferentiated keratinocytes, but indeed asymmetrically distributed in some mitoses and particularly frequent under differentiation-repressing low-calcium conditions. Numb deletion (stable knockdown by CRISPR/Cas9), however, did not affect proliferation, neither in a three-day follow up study by life cell imaging nor during a 14-day culture period, suggesting that Numb is not essential for the general control of keratinocyte division.     

Changes in wild ass (Equus hemionus khur) habitat conditions in Little Rann of Kutch,Gujarat from a remote sensing perspective

The Rann of Kutch, Gujarat is the only habitat for one of the endangered sub-species of the Asiatic wild ass (Equus hemionus khur) and most of the population survives in the Wild Ass Sanctuary in Little Rann of Kutch. The area is a saline desert with extremely sparse cover of vegetation. In the past, the habitat supported a thriving population of wild asses. However, due to extensive changes in the land-use around the Rann of Kutch, there has been an increase in the conflict of interests between man and the wild ass. The present paper seeks to analyse the situation with respect to changes in land-use, vegetation cover and salt cultivation to plan proper habitat management inside the sanctuary to mitigate the problem of crop predation by the wild ass through the use of high resolution satellite data.

The Survey of India (SOI) topographic maps of 1960 vintage were used to estimate the past habitat, land-use, vegetal cover and salt fields. The SOI topographic maps and false colour composites provided a limited number of land-use classes for a meaningful comparison of land-use changes. This data has been compared with digitally classified SPOT MLA on SIPS (Satellite Image Processing System, Hyderabad). Various techniques such as principal component analysis, normalized difference vegetation index, unsupervised and supervised classifications were carried to classify various features. Of these techniques, supervised classification provided very useful results for an effective interpretation. It was observed that there has been an increase in irrigated crop fields. This has resulted in enhanced crop predation by wild asses thereby triggering human-wild ass conflicts. The digital interpretation provided crucial information on a number of classes of land-use relevant to the habitat of wild ass. An operational basis of deriving such information for formulating effective conservation strategies is presented.     

Properties of Ternary One Dimensional Plasma Photomic Crystals for an Obliquely Incident Electromagnetic Wave Considering the Effect of Collisions in Plasma Layers

An analytical study is presented on the modal dispersion characteristics, group velocity, and effective group, as well as the phase index of a ternary one dimensional plasma photonic crystal for an obliquely incident electromagnetic wave considering the effect of collisions in plasma layers. The dispersion relation is derived by using the transfer matrix method and the boundary conditions based on electromagnetic theory. The dispersion curves are plotted for both the normal photonic band gap structure and the absorption photonic band gap structure. It is found that the increase in the angle of incidence shifts the photonic band gap toward higher frequencies. Also, the cutoff frequency is independent of collisions.