This paper presents a study on optimization of process parameters using particle swarm optimizati... more This paper presents a study on optimization of process parameters using particle swarm optimization to minimize angular distortion in 202 grade stainless steel gas tungsten arc welded plates. Angular distortion is a major problem and most pronounced among different types of distortion in butt welded plates. The process control parameters chosen for the study are welding gun angle, welding speed, plate length, welding current and gas flow rate. The experiments were conducted using design of experiments technique with five factor five level central composite rotatable design with full replication technique. A mathematical model was developed correlating the process parameters with angular distortion. A source code was developed in MATLAB 7.6 to do the optimization. The optimal process parameters gave a value of 0.0305° for angular distortion which demonstrates the accuracy of the model developed. The results indicate that the optimized values for the process parameters are capable of producing weld with minimum distortion.
In this paper, we study the problem of multicasting in TNs(Tolerant Networks). Tolerant networks ... more In this paper, we study the problem of multicasting in TNs(Tolerant Networks). Tolerant networks are a class of emerging networks that experience frequent and long-duration partitions. These net-works have a variety of applications in situations such as crisis environments and deep-space communication. Multicast supports the distribution of data to a group of users, a service needed for many potential TN applications. While multicasting in the Internet and mobile ad hoc networks has been studied extensively, due to the unique characteristic of frequent partitioning in TNs, multicasting in TNs is a considerably different and challenging problem. It not only requires new definitions of multicast semantics but also brings new issues to the design of routing algorithms. In this pa-per, we propose new semantic models for TN multicast and develop several multicast routing algorithms with different routing strategies. We present a framework to evaluate these algorithms in TNs. To the best of our knowledge, this is the first study of multicasting in TNs. Our objectives are to understand how routing performance is affected by the availability of knowledge about network topology and group membership and to guide the design of TN routing protocols. Using ns simulations, we find that efficient multicast routing for TNs can be constructed using only partial knowledge. In addition, accurate topology information is generally more important in routing at TN environment than up-to-date membership information. We also find that routing algorithms that forward data along multiple paths achieve better delivery ratios, especially when available knowledge is limited.
The histopathological effects of monocrotophos on the gill, kidney and intestine tissues of the C... more The histopathological effects of monocrotophos on the gill, kidney and intestine tissues of the Cirrhinus mrigala were determined by light microscopy. The changes in the gills were characterized by epithelial hyperplasia, aneurism, epithelial necrosis, desquamation, epithelial lifting, oedema, lamellar fusion and curling of secondary lamellae. Pycnotic nuclei in tubular epithelium, hypertrophied epithelial cells of renal tubules, contraction of the glomerulus and expansion of space inside the Bowman's capsule were observed in the kidney tissues of fish after exposure to monocrotophos. In the intestine tissues of fish exposed to monocrotophos, oedema, necrosis and atrophy of epithelial cells were observed.
Hepatoprotective activity of aqueous alcoholic (70%) extract of Rhodomyrtus tomentosa (Aiton) Hassk against antitubercular drugs induced hepatic damage
Background: Rhodomyrtus tomentosa of family Myrtaceae has been used traditionally in Chinese medi... more Background: Rhodomyrtus tomentosa of family Myrtaceae has been used traditionally in Chinese medicine for the treatment of liver disorders. However, there is no scientific evidence on the hepatoprotective potential of the plant. Aim: The present study was aimed at evaluating the hepatoprotective and antioxidant potential of the aqueous alcoholic (70%) extract of Rhodomyrtus tomentosa leaves (RTLE) based on its traditional claim in liver diseases. Materials and Methods: Hepatotoxicity was induced in albino rats by administering a combination of three antitubercular drugs, Isoniazid (7.5 mg/kg), Pyrazinamide (35 mg/kg) and Rifampicin (10 mg/kg) orally for 45 days. Alkaline phosphatase (ALP), Aspartate amino transferase (AST), Alanine aminotransferase (ALT), total protein and total bilirubin (TB) levels were estimated in serum samples using diagnostic kits. Antioxidant parameters were estimated in liver homogenates using standard methods. Statistical Analysis: The experimental mean values were compared statistically with that of toxicant group by using One‑way ANOVA followed by Newman‑Keul’s multiple tests. Results: Hepatoprotective activity of the extract was evident from the significant decrease in the elevated levels of ALT, AST, ALP and total bilirubin and an increase in the levels of total protein in comparison to toxicant control. Increased activity of antioxidant enzymes supports the in vivo antioxidant activity of the extract. Histopathological changes of the liver in the treated and control group of rats were in agreement with the hepatoprotective finding. Conclusion: RTLE exhibited hepatoprotective activity against antitubercular drug induced hepatotoxicity through a free radical scavenging effect and reduces oxidative damage caused by antitubercular drugs. Key words: Antioxidant enzymes, antitubercular drugs, hepatoprotective, Rhodomyrtus tomentosa
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