A Meaningful MD5 Hash Collision Attack

It is now proved by Wang et al., that MD5 hash is no more secure, after they proposed an attack that would generate two different messages that gives the same MD5 sum. Many conditions need to be satisfied to attain this collision. Vlastimil Klima then proposed a more efficient and faster technique to implement this attack. We use these techniques to first create a collision attack and then use these collisions to implement meaningful collisions by creating two different packages that give identical MD5 hash, but when extracted, each gives out different files with contents specified by the atacker

Origin and evolution of Gneiss-Charnockite rocks of Dharmapuri District, Tamil Nadu, India

A low- to high-grade transition area in Dharmapuri district was investigated petrologically and geochemically. The investigation confirmed the presence of a continuous section through a former lower crust, with felsic charnockites predominating the lower part and felsic gneisses the upper part. The structure of original gneisses is preserved in charnockites and the latter show petrographic evidence for prograde metamorphism. The prograde metamorphism is of isochemical nature as revealed by the similarity of compositions of tonalitic gneisses and tonalitic charnockites. However, the depletion of LIL elements particularly Rb, caused variation in K/Rb ratios from low values (345) in the gneisses in upper part to higher values (1775) in the charnockites in the lower crust. This variation in K/Rb ratio in a north to south traverse is related to the progressive break-down of hydrous minerals under decreasing H2O and increasing CO2 fluid conditions. Metasomatism and partial melting has also taken place to a limited extent along shear planes and weak zones. During cooling the H2O circulation affected substantial auto-regression in the transition zone resulting in the formation of second generation biotite

The pricing problem of public transport in Kerala

The mainstay of the public transport system in Kerala is the private stage carriages (PSC), the economics of operation of which is the subject of this paper. The long run sustainability of the sector depends on the full recovery of costs. In the presence of fixed costs, there are various approaches to the full recovery of costs and Kerala has taken the approach of regular fare revision ostensibly to cover costs based on committee recommendations. Since 1999, fares are being revised on the basis of the National Transportation Planning and Research Centre's price index for stage carriage operations (PISCO) applicable in Kerala, which, it is argued here, is one of the causes of the poor sustainability of the industry. PISCO uses average kilometers run and average concessional load factor in the computation of fares, which leads to a situation of those running above average kilometers, and carrying below average concessional load factor making above average profits and others not covering their costs. The use of weighted load factor raises general fares with the travelling public, and not the society at large, subsidizing the concessional passengers. One of the solutions to this problem lies, firstly in moving over to two - part tariff and secondly to tax financing of student subsidy. Key words: public transport, cost recovery, two-part tariff, tax financing, student subsidy JEL Classification: L92, R 4