86 research outputs found
Incorporating salinity considerations in water availability modeling
This research focused on expanding the capabilities of the Water Rights Analysis
Package (WRAP) for incorporating salinity considerations in assessments of water
availability. A simulation modeling approach was used to address this issue and a
generalized simulation model called WRAP-SALT was developed. The Brazos River
Basin served as a case study to test the simulation approach adopted by the model.
The simulation model adopts a generalized modeling approach applicable to any
river basin system. The model tracks salinity throughout a river basin system over
different periods of time for alternative scenarios of water use, reservoir system
operating policies, and salt control mechanisms. The model was applied to the Brazos
River Basin considering different management scenarios and the results obtained were
analyzed.
Reservoir reliabilities were assessed under user imposed salinity constraints. It
was observed that the water supply reliabilities decreased significantly if salinity
constraints were considered. Salt control dams proposed by the U.S. Army Corps of Engineers were also incorporated in the simulation of the river basin. It was observed
that salinity in the main stem of the Brazos River was significantly reduced. However,
no significant improvement was observed in water supply reliabilities
Enhanced photoelectrochemical response of 1D TiO₂ by atmospheric pressure plasma surface modification
In this paper we demonstrate the use of atmospheric pressure plasma jet (APPJ) to functionalize the surface of hydrothermally synthesized vertically aligned TiO2 nanorods (TNRs) for photo electrochemical (PEC) application. The TNRs functionalized with the atmospheric pressure He-plasma showed relatively higher crystallinity, improved light absorption, and change in the morphology with additional surface area, leading to an enhanced photocurrent density than that of the untreated. Achieving the PEC performance on par with the best in the literature, this APPJ treatment is shown to be a promising technique to obtain better functionality with TNR kind of materials and many other nano-micro systems for various applications such as PEC hydrogen generation
Correlated Noise Provably Beats Independent Noise for Differentially Private Learning
Differentially private learning algorithms inject noise into the learning
process. While the most common private learning algorithm, DP-SGD, adds
independent Gaussian noise in each iteration, recent work on matrix
factorization mechanisms has shown empirically that introducing correlations in
the noise can greatly improve their utility. We characterize the asymptotic
learning utility for any choice of the correlation function, giving precise
analytical bounds for linear regression and as the solution to a convex program
for general convex functions. We show, using these bounds, how correlated noise
provably improves upon vanilla DP-SGD as a function of problem parameters such
as the effective dimension and condition number. Moreover, our analytical
expression for the near-optimal correlation function circumvents the cubic
complexity of the semi-definite program used to optimize the noise correlation
matrix in previous work. We validate our theory with experiments on private
deep learning. Our work matches or outperforms prior work while being efficient
both in terms of compute and memory.Comment: Christopher A. Choquette-Choo, Krishnamurthy Dvijotham, and Krishna
Pillutla contributed equall
Deep-desulfurization of the petroleum diesel using the heterogeneous carboxyl functionalized poly-ionic liquid
Acidic carboxyl functionalized poly(ionic liquid) (CFPIL) has been synthesized and characterized by various techniques like FT-NMR, Fourier transform infrared spectroscopy (FTIR). In this work, deep oxidative desulfurization of model oil (thiophene dissolved in iso-octane) by CFPIL catalyst was carried out in presence of 30 wt% H2O2 solution as an oxidant. The effects of the hydrogen peroxide, amount of CFPIL, temperature-time and recyclability are scrutinized systematically. It was found that the effective molar proportion of H2O2 to sulfur was 4:1 at 70 °C in 180 min with 0.6 g catalyst, removing 100% thiophene from model oil. This method has shown high efficiency for the removal of thiophene, which is difficult to remove from the oil than benzothiophene and dibenzothiophene. Additionally, an oxidative desulfurization mechanism has been proposed according to the experimental results. This catalytic system by CFPIL offers advantages such as higher efficiency, low amount of ionic liquid, simple work up for separating oil from the catalyst and ease of recycling. This protocol inclines to show that diesel fuels in industry can be purified to sulfur-free or ultra-low sulfur fuels by further deep oxidative desulfurization with CFPILs after hydrodesulfurization
Curcumin Stimulates the Antioxidant Mechanisms in Mouse Skin Exposed to Fractionated γ-Irradiation
Fractionated irradiation is one of the important radiotherapy regimens to treat different types of neoplasia. Despite of the immense therapeutic gains accrued by delivering fractionated irradiation to tumors, the radiation burden on skin increases significantly. Low doses of irradiation to skin adversely affect its molecular and metabolic status. The use of antioxidant/s may help to alleviate the radiation-induced changes in the skin and allow delivering a higher dose of radiation to attain better therapeutic gains. Curcumin is an antioxidant and a free radical scavenging dietary supplement, commonly used as a flavoring agent in curries. Therefore, the effect of 100 mg/kg body weight curcumin was studied on the antioxidant status of mice skin exposed to a total dose of 10, 20 and 40 Gy γ-radiation below the rib cage delivered as a single fraction of 2 Gy per day for 5, 10 or 20 days. Skin biopsies from both the curcumin treated or untreated irradiated groups were collected for the biochemical estimations at various post-irradiation times. The irradiation of animals caused a dose dependent decline in the glutathione concentration, glutathione peroxidase, and superoxide dismutase activities and increased the lipid peroxidation in the irradiated skin. Curcumin treatment before irradiation resulted in a significant rise in the glutathione concentration and activities of both the glutathione peroxidase and superoxide dismutase enzymes in mouse skin, whereas lipid peroxidation declined significantly. The present study indicates that curcumin treatment increased the antioxidant status of mouse exposed to different doses of fractionated γ-radiation
Early and Accurate Model of Malignant Lung Nodule Detection System with Less False Positives
ABSTRACT The objective of this work is to identify the malignant lung nodules accurately and early with less false positives. ‘Nodule’ is the 3mm to 30mm diameter size tissue clusters present inside the lung parenchyma region. Segmenting such a small nodules from consecutive CT scan slices are a challenging task. In our work Auto-seed clustering based segmentation technique is used to segment all the possible nodule candidates. Efficient shape and texture features (2D and 3D) were computed to eliminate the false nodule candidates. The change in centroid position of nodule candidates from consecutive slices was used as a measure to remove the vessels. The two-stage classifier is used in this work to classify the malignant and benign nodules. First stage rule-based classifier producing 100 % sensitivity, but with high false positive of 12.5 per patient scan. The BPN based ANN classifier is used as the second-stage classifier which reduces a false positive to 2.26 per patient scan with a reasonable sensitivity of 88.8%. The Rate of Nodule Growth (RNG) was computed in our work to measure the nodules growth between the two scans of the same patient taken at different time interval. Finally, the nodule growth predictive measure was modeled through the features such as compactness (CO), mass deficit (MD), mass excess (ME) and isotropic factor(IF). The developed model results show that the nodules which have low CO, low IF, high MD and high ME values might have the potential to grow in future
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