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81.
Kannan Rangasayee List Fred Joslin Chase Rossy Andres Marquez Nandwana Peeyush 《Metallurgical and Materials Transactions A》2023,54(4):1062-1069
Metallurgical and Materials Transactions A - This study investigated the effect of laser powder bed fusion process parameters on the microstructure and properties of maraging steel. The results... 相似文献
82.
About 170 nations have been affected by the COvid VIrus Disease-19 (COVID-19) epidemic. On governing bodies across the globe, a lot of stress is created by COVID-19 as there is a continuous rise in patient count testing positive, and they feel challenging to tackle this situation. Most researchers concentrate on COVID-19 data analysis using the machine learning paradigm in these situations. In the previous works, Long Short-Term Memory (LSTM) was used to predict future COVID-19 cases. According to LSTM network data, the outbreak is expected to finish by June 2020. However, there is a chance of an over-fitting problem in LSTM and true positive; it may not produce the required results. The COVID-19 dataset has lower accuracy and a higher error rate in the existing system. The proposed method has been introduced to overcome the above-mentioned issues. For COVID-19 prediction, a Linear Decreasing Inertia Weight-based Cat Swarm Optimization with Half Binomial Distribution based Convolutional Neural Network (LDIWCSO-HBDCNN) approach is presented. In this suggested research study, the COVID-19 predicting dataset is employed as an input, and the min-max normalization approach is employed to normalize it. Optimum features are selected using Linear Decreasing Inertia Weight-based Cat Swarm Optimization (LDIWCSO) algorithm, enhancing the accuracy of classification. The Cat Swarm Optimization (CSO) algorithm’s convergence is enhanced using inertia weight in the LDIWCSO algorithm. It is used to select the essential features using the best fitness function values. For a specified time across India, death and confirmed cases are predicted using the Half Binomial Distribution based Convolutional Neural Network (HBDCNN) technique based on selected features. As demonstrated by empirical observations, the proposed system produces significant performance in terms of f-measure, recall, precision, and accuracy. 相似文献
83.
A survey of perfluorooctane sulfonate and related perfluorinated organic compounds in water,fish, birds,and humans from Japan 总被引:4,自引:0,他引:4
Taniyasu S Kannan K Horii Y Hanari N Yamashita N 《Environmental science & technology》2003,37(12):2634-2639
Occurrence of perfluorooctane sulfonate (PFOS) in the tissues of humans and wildlife is well documented. In this study, concentrations and distribution of PFOS, perfluorohexane sulfonate (PFHS), and perfluorobutane sulfonate (PFBS) were determined in samples of surface water, fish and bird blood and livers, and human blood collected in Japan. Notable concentrations of PFOS were found in surface water and fish from Tokyo Bay. PFOS was found in all of the 78 samples of fish blood and liver analyzed. Based on the concentrations of PFOS in water and in fish livers, bioconcentration factors were calculated to range from 274 to 41 600. Concentrations of PFOS in the blood of Japanese human volunteers ranged from 2.4 to 14 ng/mL. PFHS was detected in 33% of the fishes analyzed, at concentrations severalfold less than those of PFOS. 相似文献
84.
To quantitatively characterize the substances contributing to estrogenic activity in river water, in vitro bioassay using MVLN cells and instrumental analysis using liquid chromatograph–mass spectrometer (LC/MS) or liquid chromatograph–tandem mass spectrometer (LC/MS/MS) were applied to river water extracts taken from various locations in the Tama River, Japan. Tama River water samples were extracted using solid phase extraction and the crude extracts were fractionated by high-performance liquid chromatography (HPLC) into 10 fractions. The sixth fraction contained nonylphenol (NP) and octylphenol (OP) at concentrations in the range of 51.6–147 and 6.9–81.9 ng/L, respectively (concentrations corresponding to the original sample volumes). No estrogenic activity, expressed as 17β-estradiol equivalents (E2-EQB), however, was observed in this fraction (<0.6 ng-E2eq/L). Instrumentally determined estrogenic activity (E2-EQC), which is the concentrations of NP and OP multiplied by their corresponding relative potency, was below the detection limit of the MVLN cell bioassay. Estrogenic activities were detected only in HPLC fraction nos. 7, 8 and 9. Estrone (E1), estradiol (E2) and bisphenol A (BPA) were detected in these fractions. Estriol (E3) and ethynylestradiol (EE2) were not detected (<0.2 ng/L) in these fractions. The calculated E2-EQC for BPA was below the detection limit of bioassay. The E2-EQC for E1 and E2 were on the same order as the estrogenic activity determined by the bioassay (E2-EQB). The ratios of E2-EQC and E2-EQB for E1 and E2 in the three factions collectively (nos. 7–9) were 0.49–0.97 and 0.29–1.12, respectively. Above results indicated that the major causal substances to the estrogenic activity in the Tama River were E1 and E2. 相似文献
85.
Gao Xiao-Zhi Nalluri Madhu Sudana Rao Kannan K. Sinharoy Diptendu 《中国科学:技术科学(英文版)》2021,64(3):508-520
With the pervasive generation of information from a wide range of sensors and devices, there always exist a large number of input features in databases, thus complicating machine learning problem formulation. However, certain features are relatively impertinent to specific problems, which may degrade the performances of classifiers in terms of prediction accuracy, sensitivity,specificity, and recall rate. The main goal of a multi-objective optimization problem is to identify the subsets of the given features. To this end, a hybrid cat swarm optimization(HCSO) algorithm is proposed in our paper for performance improvement of the basic cat swarm optimization(CSO) that incorporates guided and competitive inherent characteristics into the original CSO. The performance of HCSO has been tested by finding the optimal feature subset for 15 benchmark datasets. The number of class labels for these datasets varies between 2 and 40. The time complexity analysis of both CSO and HCSO has also been evaluated. Moreover, the performance of the proposed algorithm has been compared with that of simple CSO and other state-ofthe-art techniques. The performances obtained by HCSO have an average 2.68% improvement with a standard deviation of 2.91.The maximum performance improvement is up to 10.09% in prediction accuracy. Tested on the same datasets, CSO has yielded improvements within the range of-7.27% to 8.51% with an average improvement 0.9% and standard deviation 3.96. The statistical tests carried out in the experiments prove that HCSO manifests a moderately better feature selection capacity than that of its counterparts. 相似文献
86.
Ponnusamy Nandha Kumar Shangavi Subramanian Uthirapathy Vijayalakshmi Sanjeevi Kannan 《Journal of the American Ceramic Society》2020,103(6):3528-3540
Structurally stable β-Ca3(PO4)2/t-ZrO2 composite mixtures with the aid of Dy3+ stabilizer were accomplished at 1500°C. The precursors comprising Ca2+, P5+, Zr4+, and Dy3+ have been varied to obtain five different combinations. The results revealed the fact that complete phase transformation of calcium-deficient apatite to β-Ca3(PO4)2 occurred only at 1300°C, whereas the evidence of t-ZrO2 crystallization is obvious at 900°C. The dual occupancy of Dy3+ at β-Ca3(PO4)2 and t-ZrO2 structures was evident; however, Dy3+ initially prefers to occupy β-Ca3(PO4)2 lattice until its saturation limit and thereafter accommodates at the lattice site of ZrO2. The typical absorption and emission behavior of Dy3+ were noticed in all the systems and, moreover, the surrounding symmetry of Dy3+ domains has been determined from the luminescence study. All the systems ensured paramagnetic response that is generally contributed by the presence of Dy3+. A gradual increment in the phase content of t-ZrO2 in the composite mixtures ensured a significant improvement in the hardness and Young's modulus of the investigated compositions. 相似文献
87.
Narang Rajan Chandrasekaran Kannan Gupta Arvind 《Journal of Failure Analysis and Prevention》2017,17(3):595-601
Journal of Failure Analysis and Prevention - Magnetic flux leakage (MFL) principle is widely used in detecting defects in cross-country pipelines. The tools based on the MFL techniques termed as... 相似文献
88.
Rangasayee Kannan Yiyu Wang Leijun Li 《Metallurgical and Materials Transactions A》2017,48(3):948-952
A unique dilatation trend is observed for isothermal bainite transformation in Fe-0.84 pct C-1 pct Cr-1 pct Mn steel. The dilatation is found to occur in two stages with volumetric contraction dominating the first stage, followed by volumetric expansion dominating the second stage. Through electron microscopic characterization, bainitic microstructure is identified as inverse bainite with cementite (Fe3C) nucleating first from supersaturated austenite followed by the transformation of ferrite and secondary carbides (Fe3C, Fe2C, and Fe5C2) from carbon-depleted austenite. 相似文献
89.
This paper discusses the iterative provision of modelling insights on long-term decarbonisation scenarios for UK energy policy makers. A multi-year model construction process of the UK MARKAL-Macro-hybrid energy-economic model, and four subsequent major policy analyses illustrates the scope of this interaction. The initial set of modelling runs focused on the technical feasibility of long-term 60% carbon dioxide (CO2) reduction scenarios, the role of key technologies, and the underlying uncertainties. Furthermore subsequent modelling studies were aimed to generate insights on more stringent targets, and on issues and uncertainties that may make targets harder to achieve. Hence, this paper analyses the large number of long-term UK CO2 reduction scenarios through a clustering approach on target stringency and barriers to implementation. Robust findings and key uncertainties are highlighted, including the critical role of the power sector, trade-offs between resources, sectors, key energy technologies and behavioural responses, and the increasing level and spread of CO2 marginal prices and GDP impacts. The relevance and use of modelling insights to the UK energy policy process is shown in the continuation of the energy modelling–policy interface. This constitutes both ongoing model development, and nuanced scenario analysis designed to further explore key uncertainties in evolving policy issues. 相似文献
90.
To test for a regulatory defect in adipose triacylglycerol (essential) fatty acid mobilization in lymphoma-bearing mice, free
[1-14C]linoleic acid/mouse serum albumin was injectediv into lymphoma-bearing and control mice, adapted to a reversed light cycle, and studied in three dietary states in the dark
period. Mean daily food intake decreased in mice with small and large tumor burdens. Plasma free fatty acid (FFA) oxidation
rates, which approximate FFA mobilization rates, were estimated by multicompartmental analysis (CONSAM). Oxidation of linoleate
to CO2 was reduced significantly (85%) inad libitum fed as compared to briefly fasted control mice but not in fedvs. fasted mice with large or small tumor burdens. However, plasma FFA oxidation rates to CO2 did not differ in briefly fasted tumor-bearing and pairfed control mice. When re-fed a 250-mg test meal, briefly fasted mice
with small tumors suppressed plasma free linoleic acid oxidation, as did controls. During simulated night, mildly anorexic,
tumor-bearing mice with small tumor burdens mobilized essential fatty acids much faster than controls. This could explain
body fat loss. The abnormally rapid rates of FFA (free linoleic acid) mobilization at night probably result from anorexia
rather than from inability of food to suppress fat mobilization. 相似文献