CFD simulation of flow past MAV wings

Turbulent flow past low aspect ratio (AR) thin wing used for two different MAV (Micro Air Vehicles) configurations viz. Black Kite and Golden Hawk has been carried out in order to analyze their aerodynamic characteristics. The Reynolds (Re) number for these two wings based on the root chord are 2.4´105 and 1.72´ 105 respectively. These simulations have been carried out using the in-house flow solution code to solve the Unsteady Reynolds Averaged Navier Stokes (URANS) equations coupled to different turbulence models. The standard k-e model has been used to simulate the turbulence for the Black Kite wing. The influence of three different turbulence models (standard k-e, SA and SST) in predicting the aerodynamic coefficient has been studied for the Golden Hawk configuration. In the present study the aerodynamic characteristics computed for the two wing configurations are compared with the CSIR-NAL experiments. The cross flow patterns and the tip vortex for the Golden Hawk wing are presented and discussed

CFD simulation using FLUENT and RANS3D - A validation exercise

The present work involves two-dimensional numerical simulation of three benchmark problems like (i) Laminar flow in a lid driven cavity (ii) Turbulent flow past a backward facing step and (iii) turbulent flow past NACA0012 aerofoil, using in-house flow solution code RANS3D and the commercially available FLUENT code. The results obtained using these codes are compared with the available measurement data and/or other computations

Neural Decoder for Topological Codes using Pseudo-Inverse of Parity Check Matrix

Recent developments in the field of deep learning have motivated many researchers to apply these methods to problems in quantum information. Torlai and Melko first proposed a decoder for surface codes based on neural networks. Since then, many other researchers have applied neural networks to study a variety of problems in the context of decoding. An important development in this regard was due to Varsamopoulos et al. who proposed a two-step decoder using neural networks. Subsequent work of Maskara et al. used the same concept for decoding for various noise models. We propose a similar two-step neural decoder using inverse parity-check matrix for topological color codes. We show that it outperforms the state-of-the-art performance of non-neural decoders for independent Pauli errors noise model on a 2D hexagonal color code. Our final decoder is independent of the noise model and achieves a threshold of $10 \%$. Our result is comparable to the recent work on neural decoder for quantum error correction by Maskara et al.. It appears that our decoder has significant advantages with respect to training cost and complexity of the network for higher lengths when compared to that of Maskara et al.. Our proposed method can also be extended to arbitrary dimension and other stabilizer codes.Comment: 12 pages, 12 figures, 2 tables, submitted to the 2019 IEEE International Symposium on Information Theor

Surface motion analysis for the natural ankle and for Total Ankle Replacements with different articular surface geometries

The increasing success and establishment of arthroplasty procedures of the knee and hip over the years, has been reason enough for the want to create a functional Total Ankle Replacement, in an attempt to phase out ankle arthodesis. The implant models such as those developed by Inman and Buechel-Pappas were critical to this process gaining momentum. Most recently, the work of Siegler et al. proposed a new patient specific and anatomically accurate model of a TAR, which also attempts to reproduce the implant models with ligament stability, mechanical alignment, and joint kinematics. This study focusses on one of the aspects of joint kinematics of the ankle complex, namely, the surface to surface interaction of the bones and its analysis during the various types of motion, by means of distance mapping. During the physical experimentation, the individual bones of the ankle joint complex are fitted with fiduciary markers, which enables the recording of position data at predefined time steps and applied torque. This is done for the different neutral positions of the ankle, as well as the different types of motion of the ankle joint, namely, dorsi-plantar flexion, inversion-eversion, and internal-external rotation. These distance maps are gradient patterns on the articulating surfaces taken in pairs, which provide us with information regarding the displacement of the concerned bones at every time step, for a specific motion type. By studying these maps, we hope to achieve a more definitive analysis of the surface interaction of the bones whilst fit with a TAR model, thus helping us achieve an implant design with the best morphological replications.M.S., Mechanical Engineering -- Drexel University, 201

Mind over matter: investigation of materialization of intentions

In this article, we present our investigation of materialization of intentions using the input-output data based Six Sigma methodology for problem solving. The investigation is inspired by our respective Gurus, the wisdom of present and past seers, and the works of several scientists. We present two examples of materialization of intentions (change of pH and levitation). The pH example is preliminary requiring additional experimentation. We believe that the evidence presented is very supportive of the hypothesis of materialization of intentions. We hope this paper will contribute towards the unfolding of a Copernican-like revolution which will have profound positive impact on humanity

Evidence for a differential contribution of early perceptual and late cognitive processes during encoding to episodic memory impairment in schizophrenia

Objectives: Schizophrenia is characterised by significant episodic memory impairment that is thought to be related to problems with encoding, however the neuro-functional mechanisms underlying these deficits are not well understood. The present study used a subsequent recognition memory paradigm and event-related potentials (ERPs) to investigate temporal aspects of episodic memory encoding deficits in schizophrenia. Methods: Electroencephalographic data was recorded in 24 patients and 19 healthy controls whilst participants categorised single words as pleasant/unpleasant. ERPs were generated to subsequently recognised versus unrecognised words on the basis of a forced-choice recognition memory task. Subsequent memory effects were examined with the late positive component (LPP). Group differences in N1, P2, N400 and LPP were examined for words correctly recognised. Results: Patients performed more poorly than controls on the recognition task. During encoding patients had significantly reduced N400 and LPP amplitudes than controls. LPP amplitude correlated with task performance however amplitudes did not differ between patients and controls as a function of subsequent memory. No significant differences in N1 or P2 amplitude or latency were observed. Conclusions: The present results indicate that early sensory processes are intact and dysfunctional higher order cognitive processes during encoding are contributing to episodic memory impairments in schizophrenia

Conceptual Development of a Transformable Chair Using TRIZ

Abstract There is increased sophistication in the field of transformable furniture which will acquire less space with minimum weight. This applied research was done to develop a transformable chair which would satisfy various needs of people. The study of existing models was carried out and survey was conducted to understand the voice of the customer. Concept generation tool (here TRIZ) was used to generate various concepts. Newer concepts were modeled in SOLIDWORKS. Customer feedback for the newly modeled concepts was carried out to narrow down our choices to only single concept. After choosing the concept, Golden ratio was applied to it and the results were analyzed

Enhancing production and flow of freshwater ecosystem services in a managed Himalayan river system under uncertain future climate

Future climate change will likely impact the multiple freshwater Ecosystem Services (fES) provided by catchments through their landscapes and river systems. However, there is high spatio-temporal uncertainty on those impacts linked to climate change uncertainty and the natural and anthropogenic interdependencies of water management systems. This study identifies current and future spatial patterns of fES production in a highly managed water resource system in northern India to inform the design and assessment of plausible adaptation measures to enhance fES production in the catchment under uncertain climate change. A water resource systems modelling approach is used to evaluate fES across the full range of plausible future scenarios, to identify the (worst-case) climate change scenarios triggering the greatest impacts and assess the capacity of adaptation to enhance fES. Results indicate that the current and future states of the fES depend on the spatial patterns of climate change and the impacts of infrastructure management on river flows. Natural zones deliver more regulating and cultural services than anthropized areas, although they are more climate sensitive. The implementation of a plausible adaptation strategy only manages to slightly enhance fES in the system with respect to no-adaptation. These results demonstrate that water resource systems models are powerful tools to capture complex system dependencies and inform the design of robust catchment management measures. They also highlight that mitigation and more ambitious adaptation strategies are needed to offset climate change impacts in highly climate sensitive catchment

Hypersensitivity Pneumonitis-like Granulomatous Lung Disease with Nontuberculous Mycobacteria from Exposure to Hot Water Aerosols

OBJECTIVE: Human activities associated with aerosol-generating hot water sources are increasingly popular. Recently, a hypersensitivity pneumonitis (HP)-like granulomatous lung disease, with non-tuberculous mycobacteria from exposure to hot water aerosols from hot tubs/spas, showers, and indoor swimming pools, has been described in immunocompetent individuals (also called “hot tub lung”). Our objective in this study was to examine four additional cases of hot tub lung and compare these cases with others reported in the English print literature on this disease. DATA SOURCES AND EXTRACTION: We retrospectively reviewed all cases (n = 4) of presumptively diagnosed hot tub lung in immunocompetent individuals at the various physician practices in Springfield, Illinois, during 2001–2005. In addition, we searched MEDLINE for cases of hot tub lung described in the literature. DATA SYNTHESIS: We summarized the clinical presentation and investigations of four presumptive cases and reviewed previously reported cases of hot tub lung. CONCLUSIONS: There is a debate in the literature whether hot tub lung is an HP or a direct infection of the lung by nontuberculous mycobacteria. Primary prevention of this disease relies on ventilation and good use practices. Secondary prevention of this disease requires education of both the general public and clinicians to allow for the early diagnosis of this disease