Puneet Singh

Bio: Puneet Singh is an academic researcher from University of Michigan. The author has contributed to research in topics: Vortex & Coaxial. The author has an hindex of 5, co-authored 17 publications receiving 195 citations. Previous affiliations of Puneet Singh include Indian Institute of Technology Kanpur.

Reusable electrospun mesoporous ZnO nanofiber mats for photocatalytic degradation of polycyclic aromatic hydrocarbon dyes in wastewater.

Abstract: We demonstrate a new method for the fabrication of free-standing mats of mesoporous ZnO nanofibers by electrospinning a blend of zinc acetate with a carrier polymer, polyacrylonitrile (PAN) in N,N-dimethyl-formamide (DMF) solvent. Decomposition of PAN by calcination produces porous ZnO nanofibers with fiber diameters in the range of 50–150 nm depending on the electrospinning conditions such as the precursor solution concentration, electric field strength, and solution flow rate. The fibers are characterized for their morphology, phase composition, band gap, crystallinity, surface area, and porosity. In this paper, optimized mats of ZnO nanofibers with an average fiber diameter of 60 nm are shown to be highly effective in the photocatalytic degradation of the PAH dyes – naphthalene and anthracene. Nanofiber mats fabricated here may also find applications in gas sensing, piezoelectric devices, optoelectronics, and photocatalysis.

Application of Vortex Methods to Coaxial Rotor Wake and Load Calculations in Hover

Abstract: The coaxial rotor has distinct advantages in hover performance and forward flight compared to a conventional isolated rotor. The viscous vortex particle approach based on the Lagrangian formulation...

The Global Macroeconomic Burden of Breast Cancer: Implications for Oncologic Surgery.

Abstract: Objective In this study, we quantified the global macroeconomic burden of breast cancer to underscore the critical importance of improving access to oncologic surgical care internationally. Summary background data Breast cancer mortality in many low and middle-income countries (LMICs) is dramatically higher than in high-income countries. Prior to identifying solutions, however, it is important to first define the burden of disease. Methods Data from the Institute of Health Metrics and Evaluation (2005-2015) were used to assess epidemiologic trends for 194, middle, and low-income countries. Economic burden defined by Welfare Loss (WL) was calculated by measuring disability-adjusted-life-years lost to breast cancer alongside the dollar equivalent of a value of statistical life year and as a function of each country's gross domestic product (GDP). Results Annual mortality rates among breast cancer patients were significantly greater in LMICs in South Asia (3.06 per 100 women) and Sub-Saharan Africa (2.76 per 100 women), compared with high-income countries like the United States (1.69 per 100 women). From 2005-2015, mortality in South Asia increased by 8.20% and decreased by 6.45% in Sub-Saharan Africa; mortality rates in 2015 were observed as 27.9 per 100,000 in South Asia and 18.61 per 100,000 in Sub-Saharan Africa. Countries in South Asia demonstrated the greatest rise in WL due to breast cancer, from 0.05% to 0.08% of GDP. Conclusions The burden of disease and economic impact of breast cancer is intensifying in LMICs. Global efforts to improve access to surgical care for women with breast cancer could reduce mortality and mitigate the social and financial impact of this disease in LMICs.

Experimental Performance Evaluation of Coaxial Rotors for a Micro Aerial Vehicle

Abstract: Because of their potential for application in both civil and military sectors as well as the challenge in designing a tiny flying vehicle, micro aerial vehicles have attracted enormous attention. Several configurations of micro aerial vehicles are under development, namely fixed wing, rotary wing, and flapping wing. Under rotary-wing micro aerial vehicles, coaxial contrarotating configurations with a stabilizer bar seem to provide excellent stability behavior in pitch and roll degrees of freedom. This paper presents the results of an experimental study performed on a coaxial-contrarotor helicopter model to evaluate the performance of the rotor system using different rotor blades. The thrust and power of the rotors in independent and coaxial configurations were observed. The percentage thrust loss in the coaxial configuration was seen to be dependent on the ratio of the upper- and lower-rotor revolutions per minute as well as the spacing between the rotors. A theoretical analysis using a nonuniform inflow ...

Latent Dirichlet allocation (LDA) and topic modeling: models, applications, a survey

Abstract: Topic modeling is one of the most powerful techniques in text mining for data mining, latent data discovery, and finding relationships among data and text documents. Researchers have published many articles in the field of topic modeling and applied in various fields such as software engineering, political science, medical and linguistic science, etc. There are various methods for topic modelling; Latent Dirichlet Allocation (LDA) is one of the most popular in this field. Researchers have proposed various models based on the LDA in topic modeling. According to previous work, this paper will be very useful and valuable for introducing LDA approaches in topic modeling. In this paper, we investigated highly scholarly articles (between 2003 to 2016) related to topic modeling based on LDA to discover the research development, current trends and intellectual structure of topic modeling. In addition, we summarize challenges and introduce famous tools and datasets in topic modeling based on LDA.

Latent Dirichlet Allocation (LDA) and Topic modeling: models, applications, a survey

Abstract: Topic modeling is one of the most powerful techniques in text mining for data mining, latent data discovery, and finding relationships among data, text documents. Researchers have published many articles in the field of topic modeling and applied in various fields such as software engineering, political science, medical and linguistic science, etc. There are various methods for topic modeling, which Latent Dirichlet allocation (LDA) is one of the most popular methods in this field. Researchers have proposed various models based on the LDA in topic modeling. According to previous work, this paper can be very useful and valuable for introducing LDA approaches in topic modeling. In this paper, we investigated scholarly articles highly (between 2003 to 2016) related to Topic Modeling based on LDA to discover the research development, current trends and intellectual structure of topic modeling. Also, we summarize challenges and introduce famous tools and datasets in topic modeling based on LDA.

Model identification and control of solution crystallization processes: a review

Abstract: The modeling of crystal quality (size, shape, and purity) is discussed. Numerical methods for the model solution are reviewed including collocation and Galerkin's method on finite elements. Measurement technologies for on-line crystal size distribution are presented. The difficulties with laser light scattering methods are discussed in detail. Parameter estimation is reviewed and new methods based on nonlinear optimization are presented. Sample calculations of parameters and their uncertainty from experimental data are included. The research literature covering control of continuous and batch crystallization is reviewed, and sample calculations of optimal cooling profiles for batch crystallizers are presented