Parametric Optimization of MIG Welding on 316L Austenitic Stainless Steel by Grey-based Taguchi Method

AbstractIn the present work, visual inspection and X-ray radiographic test has been conducted in order to detect surface and sub-surface defects of weld specimens made of AISI 316L austenitic stainless steels. Effect of current, gas flow rate and nozzle to plate distance on quality of weld in metal inter gas arc welding of AISI 316L austenitic stainless steel has been studied in the present work through experiments and analyses. Butt welded joints have been made by using several levels of current, gas flow rate and nozzle to plate distance. The quality of the weld has been evaluated in terms of yield strength, ultimate tensile strength and percentage of elongation of the welded specimens. The observed data have been interpreted, discussed and analyzed by using Grey - Taguchi methodology

EFFECT OF CULTURE PARAMETERS ON PROTEASE AND CELLULASE PRODUCTION BY TWO BACTERIAL STRAINS, Corynebacterium alkanolyticum ATH3 AND Bacillus licheniformis CBH7 ISOLATED FROM FISH GUT

Microbial protease and cellulase are in high demand by different industries due to their minimal cost and availability. This study was aimed to maximize the production of protease and cellulase using two bacteria, Corynebacterium alkanolyticum ATH3 and Bacillus licheniformis CBH7, isolated from fish gut. This study demonstrated the effect of different culture parameters in protease and cellulase production using two different bacterial strains. Results of this study clearly indicated the importance of different parameters such as moisture content, pH, incubation temperature, incubation period, inoculum size, carbon sources and nitrogen sources in enzyme production. The most critical parameters affecting the enzymes production were pH, temperature, carbon and nitrogen sources. Further investigations are required to enhance the enzymes production using genetic engineering

One-Key Compression Function Based MAC with Security beyond Birthday Bound

Ga{\v z}i et al. [CRYPTO 2014] analyzed the NI-MAC construction proposed by An and Bellare [CRYPTO 1999] and gave a tight birthday-bound of $O(\ell q^{2}/2^{n})$, as an improvement over the previous bound of $O(\ell^{2}q^{2}/2^{n})$. In this paper, we design a simple extension of NI-MAC, called NI$^+$-MAC, and prove that it has security bound beyond birthday (BBB) of order $O(q^2\ell^2 / 2^{2n})$ provided $\ell \leq 2^{n/4}$. Our construction not only lifts the security of NI-MAC beyond birthday, it also reduces the number of keys from 2 (NI uses 2 independent keys) to 1. Before this work, Yasuda had proposed [FSE 2008] a single fixed-keyed compression function based BBB-secure MAC with security bound $O(\ell q^2/2^{2n})$ that uses an extra mask, requires a storage space to store the mask. However, our proposed construction NI$^+$ does not require any extra mask and thereby has reduced the state size compared to Yasuda\u27s proposal [FSE 2008] with providing the same order of security bound for light-weight application

Optimization of process parameters of TIG welding of duplex stainless steel without filler rod by grey-Taguchi method

385-392Input parameters of welding have played an important role in producing the quality of welding joint. Welding quality has been improved using proper process parameters with sound knowledge base. Current, welding speed and the shielding gas flow rate have been used as the most important influencing parameters of Tungsten Inert Gas (TIG) welding on Duplex Stainless Steel (DSS). In the present work, multi-objective optimization of TIG welding process parameters of Duplex Stainless Steel - ASTM/UNS 2205 has been determined. These welding process parameters have been optimized to achieve the required quality of DSS welding joints. The quality of the TIG welding on DSS has been evaluated in term of tensile test. The grey-based Taguchi technique has been used to solve this multi- optimization problem. Analysis of Variance (ANOVA) has been applied to evaluate the significance of the individual factors on desired results which are ultimate tensile strength, yield strength and percentage of elongation. Additional confirmatory experiment has been done to verify the optimal results. The application possibilities of the grey-based Taguchi method for incessant development of welding quality of DSS in many fields, like chemical industries, oil refineries, gas manufacturing industries etc. have been shown by this work

Optimization of process parameters of TIG welding of duplex stainless steel without filler rod by grey-Taguchi method

Input parameters of welding have played an important role in producing the quality of welding joint. Welding quality has been improved using proper process parameters with sound knowledge base. Current, welding speed and the shielding gas flow rate have been used as the most important influencing parameters of Tungsten Inert Gas (TIG) welding on Duplex Stainless Steel (DSS). In the present work, multi-objective optimization of TIG welding process parameters of Duplex Stainless Steel - ASTM/UNS 2205 has been determined. These welding process parameters have been optimized to achieve the required quality of DSS welding joints. The quality of the TIG welding on DSS has been evaluated in term of tensile test. The grey-based Taguchi technique has been used to solve this multi- optimization problem. Analysis of Variance (ANOVA) has been applied to evaluate the significanc e of the individual factors on desired results which are ultimate tensile strength, yield strength and percentage of elongation. Additional confirmatory experiment has been done to verify the optimal results. The application possibilities of the grey-based Taguchi method for incessant development of welding quality of DSS in many fields, like chemical industries, oil refineries, gas manufacturing industries etc. have been shown by this work

Double-block Hash-then-Sum: A Paradigm for Constructing BBB Secure PRF

SUM-ECBC (Yasuda, CT-RSA 2010) is the first beyond birthday bound (BBB) secure block cipher based deterministic MAC. After this work, some more BBB secure deterministic MACs have been proposed, namely PMAC_Plus (Yasuda, CRYPTO 2011), 3kf9 (Zhang et al., ASIACRYPT 2012) and LightMAC_Plus (Naito, ASIACRYPT 2017). In this paper, we have abstracted out the inherent design principle of all these BBB secure MACs and present a generic design paradigm to construct a BBB secure pseudo random function, namely Double-block Hash-then- Sum or in short (DbHtS). A DbHtS construction, as the name implies, computes a double block hash on the message and then sum the encrypted output of the two hash blocks. Our result renders that if the underlying hash function meets certain security requirements (namely cover-free and block-wise universal advantage is low), DbHtS construction provides 2n/3-bit security. We demonstrate the applicability of our result by instantiating all the existing beyond birthday secure deterministic MACs (e.g., SUM-ECBC, PMAC_Plus, 3kf9, LightMAC_Plus) as well as a simple two-keyed variant for each of them and some algebraic hash based constructions

Single Key Variant of PMAC_Plus

At CRYPTO 2011, Yasuda proposed the PMAC_Plus message authentication code based on an n-bit block cipher. Its design principle inherits the well known PMAC parallel network with a low additional cost. PMAC_Plus is a rate-1 construction like PMAC (i.e., one block cipher call per n-bit message block) but provides security against all adversaries (under black-box model) making queries altogether consisting of roughly upto 22n/3 blocks (strings of n-bits). Even though PMAC_Plus gives higher security than the standard birthday bound security, with currently available best bound, it provides weaker security than PMAC for certain choices of adversaries. Moreover, unlike PMAC, PMAC_Plus operates with three independent block cipher keys. In this paper, we propose 1k-PMAC_Plus, the first rate-1 single keyed block cipher based BBB (Beyond Birthday Bound) secure (in standard model) deterministic MAC construction without arbitrary field multiplications. 1k-PMAC_Plus, as the name implies, is a simple one-key variant of PMAC_Plus. In addition to the key reduction, we obtain a higher security guarantee than what was proved originally for PMAC_Plus, thus an improvement in two directions

Nutritional evaluation of soybean meal after fermentation with two fish gut bacterial strains, Bacillus cereus LRF5 and Staphylococcus caprae CCF2 in formulated diets for Labeo rohita fingerlings

Twelve isonitrogenous (35 % crude protein) and isocaloric (18.0 kJ/g) diets were formulated incorporating raw and fermented soybean meal (SBM) at 15%, 30%, 45% and 60% levels by weight. Two phytase-producing bacterial strains, Bacillus cereus LRF5 and Staphylococcus caprae CCF2 isolated from the gut of adult Labeo rohita and Catla catla, respectively were used for fermentation of SBM. Fermentation of SBM was effective in reducing the anti-nutritional factors, trypsin inhibitor and phytic acid and enhancing protein, lipid and mineral concentration. The response of L. rohita, fingerlings (initial weight 3.33±0.07 g) fed the experimental diets for 100 days was compared with fish fed a fish meal based diet. In terms of growth, feed conversion ratio and protein efficiency ratio, diet S7 containing 45% SBM fermented with B. cereus LRF5 resulted in a significantly (P<0.05) better performance of fish. The overall performance of L. rohita fed fermented SBM incorporated diets was better in comparison to those fed raw SBM incorporated diets. The apparent digestibility of nutrients and minerals was significantly (P<0.05) higher in fish fed diet S7. The maximum deposition of protein in the carcass was recorded in fish fed diet S7. Diets containing fermented SBM reduced fecal P levels.&nbsp

Vibrio fluvialis in Patients with Diarrhea, Kolkata, India

We identified 131 strains of Vibrio fluvialis among 400 nonagglutinating Vibrio spp. isolated from patients with diarrhea in Kolkata, India. For 43 patients, V. fluvialis was the sole pathogen identified. Most strains harbored genes encoding hemolysin and metalloprotease; this finding may contribute to understanding of the pathogenicity of V. fluvialis