Brans-Dicke theory: Jordan vs Einstein Frame

It is well known that, in contrast to general relativity, there are two conformally related frames, the Jordan frame and the Einstein frame, in which the Brans-Dicke theory, a prototype of generic scalar-tensor theory, can be formulated. There is a long standing debate on the physical equivalence of the formulations in these two different frames. It is shown here that gravitational deflection of light to second order accuracy may observationally distinguish the two versions of the Brans-Dicke theory.Comment: 10 pages, Accepted by Mod. Phys. Letts.

A Session based Multiple Image Hiding Technique using DWT and DCT

This work proposes Steganographic technique for hiding multiple images in a color image based on DWT and DCT. The cover image is decomposed into three separate color planes namely R, G and B. Individual planes are decomposed into subbands using DWT. DCT is applied in HH component of each plane. Secret images are dispersed among the selected DCT coefficients using a pseudo random sequence and a Session key. Secret images are extracted using the session key and the size of the images from the planer decomposed stego image. In this approach the stego image generated is of acceptable level of imperceptibility and distortion compared to the cover image and the overall security is high.Comment: 4 pages,16 figures, "Published with International Journal of Computer Applications (IJCA)

Population dynamics of penaeid prawn Penaeus merguiensis off Mumbai coast

Stock dynamics of Penaeus merguiensis was studied using length composition data collected separately for males and females during the period 1995-1998, at New Ferry Warf landing, centre in Greater Mumbai. Food and feeding, sex ratio, fecundity and length-weight relationships were worked out on a representative sub-sample. Asymptotic length (Loo) and growth coefficient (K) were estimated to be 220 mm and 1.80 per annum respectively for males. These parameters were respectively 281 mm and 1. 72 per annum in the case of females. The instantaneous rate of total mortality coefficient (Z) was found to be 9.79 and 7.44 per annum for males and females respectively. The annual natural mortality coefficient (M) was estimated to be 2.80 for males and 2.60 for females. As the exploitation ratio exceeded 0.5 in the case of both the males and females, the study suggests the necessity for reduction in fishing pressure in order to achieve Maximum Sustainable Yield (MSY)

Ytterbium doped nano-crystalline optical fiber for reduced photodarkening

We report suppression of photodarkening in Yb-doped nano-crystalline fibers in silica host. The photodarkening induced loss reduced by 20 times compared to Yb-doped aluminosilicate fibers. The laser efficiency of the nano-crystalline fiber was 79%

Grouping of Hashtags using Co-relating the Occurrence in Microblogs

In this paper we introduce a new topic model to understand the chaotic micro blogging environment by using hashtag graphs. Hash tag is symbol (#) used on social media and micro blogging sites. A word or phrase is preceded with hashtag;hashtag isgenerally used forhighlighting the topic.HGTM: Hash tag Graph based Topic model exploresan elemental proposal that uses the aspects which are suppressed by means of the hash tags that are added through the user HGTM discovers word semantic relations even if words are not correlated within aspecific tweet, hash tags are used as keywords to find the semantic relations. HGTM has the capability to Handel the sparseness and noise problem in tweets

Recent Advances in the Technology of Aluminium- Magnesium Alloys

ALLOYS of aluminium with copper. to which smallamounts of manganese. magnesium and silicon are added, belong to the well known group of alloys termed "'Duralumin ', and were amongst the earliest of aluminium alloys to be used commercially on account of their age-hardening characteristics. Alloys of aluminium with magnesium as the principal alloying element, first attracted the interest of investigators as early as 1900, and since then, cast alloys containing as much as 10% magnesium have been used for specified purpose