Equilibrium Studies on Cu(II) & UO2(II) Complexes of Isobutyric, β,β-Dibromoisobutyric & 4-Aminobutyric Acids

451-45

Complexes of Cobalt(II) with Schiff Bases Derived from Salicylaldehyde & Some Amino Acids

749-75

AN INITIAL VALUE TECHNIQUE FOR SINGULARLY PERTURBED REACTION-DIFFUSION PROBLEMS WITH A NEGATIVE SHIFT

Abstract. In this paper, a numerical method named as Initial Value Technique (IVT) is suggested to solve singularly perturbed boundary value problems for second order ordinary differential equations of reactiondiffusion type with a delay (negative shift). In this technique, the original problem of solving the second order differential equation is reduced to solving four first order singularly perturbed differential equations without delay and one algebraic equation with a delay. The singularly perturbed problems are solved by a second order hybrid finite difference scheme. An error estimate is derived by using supremum norm and it is of order O(ε + N −2 ln 2 N ), where N is a discretization parameter and ε is the perturbation parameter. Numerical results are provided to illustrate the theoretical results

Seismic Response Control Systems for Structures

Structures constructed in developing world are typically RC frames with masonry infill. These structures have little resistance for lateral loads caused by earthquake and wind. Even for  adequately designed structures also, due to permissible deformation beyond elastic limits, failure of masonry causes severe loss of life and property. In the case of structures designed to sustain excessive deformation such as of defence establishments, functioning and serviceability of machines and equipment installed therein are adversely affected. This co-lateral damage may be reduced by adopting another design philosophy of structure response control. In this methodology, a supplementary damping device is incorporated in the primary structure, which absorbs most of the seismic energy imparted to it, restricting the structural response within serviceable limits. These devices may be passive, active, semi-active or hybrid types. Other than passive all options are technology-intensive and dependent on external energy source, not a favourable proposition for developing nations. Among all the passive devices, tuned liquid dampers (TLDs) promise to be most suitable. Here, existing overhead water tanks (OHWT) may be used as TLD with slight adjustment and modification. This method will be able to control the structural response without putting any extra load on the existing or newly-designed buildings. This paper reviews various types of dampers and discusses evolution of tuned liquid dampers. A method has also been proposed for incorporating TLDs in existing and new structures. This methodology may be very useful for structures of defence establishment which are scattered and remotely placed by location, housing important equipments sensitive to vibrations, as it is free from external power dependence and regular maintenance.Defence Science Journal, 2009, 59(3), pp.239-251, DOI:http://dx.doi.org/10.14429/dsj.59.151

Relating two standard notions of secrecy

Two styles of definitions are usually considered to express that a security protocol preserves the confidentiality of a data s. Reachability-based secrecy means that s should never be disclosed while equivalence-based secrecy states that two executions of a protocol with distinct instances for s should be indistinguishable to an attacker. Although the second formulation ensures a higher level of security and is closer to cryptographic notions of secrecy, decidability results and automatic tools have mainly focused on the first definition so far. This paper initiates a systematic investigation of the situations where syntactic secrecy entails strong secrecy. We show that in the passive case, reachability-based secrecy actually implies equivalence-based secrecy for digital signatures, symmetric and asymmetric encryption provided that the primitives are probabilistic. For active adversaries, we provide sufficient (and rather tight) conditions on the protocol for this implication to hold.Comment: 29 pages, published in LMC

Cost optimization of cantilever retaining wall

This thesis presents a lucid model to obtain the optimum cost of a cantilever retaining wall having different cases of backfill (straight and inclined) and surcharge. A code written in Java, finds out all the sections of the cantilever retaining wall possible according to stability criteria that applies to all retaining walls and gives the optimum cost of a retaining wall of a given height and the required material properties to be used, while following the provisions of the Indian Standard Code, IS 456:2000for the sections. The freedom given for the person who uses the program to specify material properties and their costs add to the versatility of the code

Ultra-high temperature ceramic composite

The work carried out under the XMat research programme (Materials Systems for Extreme Environments, EPSRC Programme Grant number EP/K008749/1-2) in the field of ultra-high temperature ceramic matrix composites has been focused on the design, development and manufacture of complex shapes and large panels for use under extreme conditions. The composites are made from 2.5D woven carbon fibre preforms impregnated with HfB2 powders and with a pyrolytic carbon, PyC, matrix created using chemical vapour infiltration, CVI. More recently, the knowledge acquired during the development of these Cf-HfB2-C composites has been focused on shortening the densification time by moving from conventional CVI to Radio Frequency-heated CVI; the work has also switched to Cf-ZrB2-C composites. In addition, the use of 3D carbon fibre preforms has begun to be explored to improve the mechanical properties and also the replacement of PyC matrix with ZrB2 to reducing the oxidation of the composites at ultra-high temperature

Metavinculin modulates force transduction in cell adhesion sites

Vinculin is a ubiquitously expressed protein, crucial for the regulation of force transduction in cells. Muscle cells express a vinculin splice-isoform called metavinculin, which has been associated with cardiomyopathies. However, the molecular function of metavinculin has remained unclear and its role for heart muscle disorders undefined. Here, we have employed a set of piconewton-sensitive tension sensors to probe metavinculin mechanics in cells. Our experiments reveal that metavinculin bears higher molecular forces but is less frequently engaged as compared to vinculin, leading to altered force propagation in cell adhesions. In addition, we have generated knockout mice to investigate the consequences of metavinculin loss in vivo. Unexpectedly, these animals display an unaltered tissue response in a cardiac hypertrophy model. Together, the data reveal that the transduction of cell adhesion forces is modulated by expression of metavinculin, yet its role for heart muscle function seems more subtle than previously thought. Muscle cells express an adhesion molecule called metavinculin, which has been associated with cardiomyopathies. Here, the authors employed molecular tension sensors to reveal that metavinculin expression modulates cell adhesion mechanics and they develop a mouse model to demonstrate that the presence of metavinculin is not as critical for heart muscle function as previously thought

Imitation in Large Games

In games with a large number of players where players may have overlapping objectives, the analysis of stable outcomes typically depends on player types. A special case is when a large part of the player population consists of imitation types: that of players who imitate choice of other (optimizing) types. Game theorists typically study the evolution of such games in dynamical systems with imitation rules. In the setting of games of infinite duration on finite graphs with preference orderings on outcomes for player types, we explore the possibility of imitation as a viable strategy. In our setup, the optimising players play bounded memory strategies and the imitators play according to specifications given by automata. We present algorithmic results on the eventual survival of types