55 research outputs found
Measuring Diffusion in Stream Ciphers using Statistical Testing Methods
Confusion and diffusion suggested by Claude Shannon are two techniques that symmetric key ciphers should satisfy to prevent cryptanalysis. Diffusion dissipates the statistical properties of the plaintext over the whole ciphertext. For a block cipher, each bit of the output ciphertext block changes with probability one half for any flipped bit in the input plaintext block, implying the cipher to have good diffusion properties. This definition with slight modification can also be applied to stream ciphers but here it is enough to make sure the following: (i) to ensure an overall change in the output keystream with probability half for any flipped bit in the Key-IV bit sequence, and (ii) to verify that every bit in the output keystream changes with probability one half for any single bit flip in the key-IV bit sequence. Here we insist on using these tests together for measuring diffusion in stream ciphers. Based on this we have examined the level of diffusion exhibited by some of the eSTREAM candidates and the result is given in this paper.Defence Science Journal, 2012, 62(1), pp.6-10, DOI:http://dx.doi.org/10.14429/dsj.62.143
Weed flora of black pepper garden at high rainfall tract of northern agro-climatic zone of Kerala
Smart Safety and Accident Prevention System
The primary cause of road accident results in fatalities, serious injuries and monetary losses is known to be due to drowsy or sleepy drivers, according to analysis reports on recent traffic accidents. Lack of sleep, medication, drugs, or prolonged driving contributes to drowsiness. A system that can identify a driver’s drowsy state and warn him before an accident occurs is required to avoid roadside accidents caused by distracted driving. Many researchers have recently expressed their interest in drowsiness detection. The methods essentially involve monitoring the driver’s physiological or behavioral 1summarizes some of the most recent methods put forth in this field is given. We propose an algorithm to monitor eye blinks that uses eye feature points to determine whether the eye is open or closed and sets off an alarm if the driver is drowsy. In-depth experimental results are also provided to highlight the benefits and drawbacks of the proposed method
Catalytic anodes in electrowinning - inhibition of poisoning :part I. Cyclic voltammetric studies
Poisoning of the catalytic anodes of Mn2+ ion in metal winning electrolytes has been investigated.
Addition of soluble phosphorous (V) and arsenic (Ill) compounds has been examined as
a deterrent for MnOz deposition using cyclic voltamrnetric technique. Probable role of these compounds
in the inhibition of anodic formution of MnOz is discussed. Platinum, RuOz film electrode and
Ru02 powder compact electrode have been studied in this context
Activated lead electrodes for electrowinning operations
The need for new technology to recover metals with more energy efficiency has created
increasing interest in sulphate electrowinning systems. Development of electrocatalytic
. . anodes for oxygen evolution conditions is a subject of current interest. A kind of
. . activated elmrode with an electrocatalyst dispersed and embedded within a matrix of
lead has been investigsted. Cyclic voltammetric studies and anodic polarisation studies
. under oxygen evolution condition have been carried out in HzSOs~o lutions. The effects
of catalyst loading and acid concentration on anode potential have been discussed. RuOn
and lrOp ar&?Felectrocatalysts studied
Activated lead electrodes for electrowinning operations
The need for new technology to recover metals with more energy efficiency has created
increasing interest in sulphate electrowinning systems. Development of electrocatalytic
. . anodes for oxygen evolution conditions is a subject of current interest. A kind of
. . activated elmrode with an electrocatalyst dispersed and embedded within a matrix of
lead has been investigsted. Cyclic voltammetric studies and anodic polarisation studies
. under oxygen evolution condition have been carried out in HzSOs~o lutions. The effects
of catalyst loading and acid concentration on anode potential have been discussed. RuOn
and lrOp ar&?Felectrocatalysts studied
Catalytic anodes for electrowinning-part:I effect of methanol addition
A significant reduction in energy consumption in metal electrowinning from sulphate solutions can be achieved by the use
of catalyti: anodes in combination with methanol addition to the electrolyte. The effect of current density on methanol oxidation
has knst udied on different types of catalytic anodes like Ru4f ilm electrode and sponge electrode. The effect of periodic
current reversal on the anodic process has also been investigate
Electrowinning of zinc - Effect of metallic impurities and addition agents
The electrowinning of zinc is sensitive to metallic Impurities especially from the points of view of current efficiency and purity of the deposit. Moreover, the effect of impurities in combination is in general detrimental to electrolysis than of single impurity, The organic addition agents are known to influence the nature of deposit and current efficiency, In this context, studies have been made with regard to the influence of addition agents like fish glue, avitone, gelatin and sodium lignin sulphonate, Among the additions studied avitone shows promise from the point of view of current efficiency, The influence of metallic impurities like nickel, cobalt and antimony individually and in combination has also been investigate
Electrolytic recovery of copper and regeneration of cupric chloride etchant
The electrolytic recovery of copper and regeneration of copper chloride etchant has been studied. The effects of current density, as it concentration, cuprous and cupric ion concentration on current efficiency has been assesse
Catalytic anodes in electrowinning - inhibition of poisoning by manganese ions: Part II. Galvanic studies
The deactivation of catalytic anode caused by Mn2+ ion in electrowinning electrolytes has been studied under galvanostatic conditions. Gradual anode potential rise in presence of Mn2+ ion indicates the deterioration in the catalytic activity as a result of Mno2 formation on the electrode surface. The addition of soluble phosporous or arsenic compounds is found to restrict the rise in anode potential. Current efficiency studies made for Mno2 deposition in presence of arsenic or phosporous compound confirm the inhibiting tendency of these surface active substance on Mno2 formation. Surface characterization of polarised electrodes has also been made using scanning electron microscope
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