56 research outputs found

    Design of the drive mechanism for a reciprocating coal feeder

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    Material handling is undoubtedly the most important and in fact an indispensable job in industries for it is encountered at every stage right from the time raw materials enter the factory gate to the point when it leaves in form of finished products. The engineering of material handling falls under two categories depending on form of material: bulk solid handling and unit handling. In case of handling lumpy materials like coals etc. , feeder plays a vital role as an uninterrupted source of uniform feed provider to the conveyor system. Although several feeders like belt, apron, screw, feeders etc are available, reciprocating feeders are still in use because it ensures a continuous and controlled feed rate, is low in cost, its drive mechanism is simple, it can handle wide range of miscellaneous materials including lumps, easy in assembly and disassembly and maintenance requirement is quite low. The challenge which we have taken via the project, is to design a drive mechanism for a reciprocating coal feeder. We call it a challenge because we have to design various intricate components like couplings, worm reducers, gearbox etc. We call it complicated since all the components are interdependent on each other to a great extent. So we cannot design anything randomly . We have to take into considerations the smallest of small things like the various forces acting, how each component can fail under various stress conditions. We have to optimize everything right from the motor selection, to speed reduction ratio selection, to the capacity of coal which we can handle. We are going to follow the above-mentioned strategies so that our project does not remain just a theory but can become a reality for industries

    Accelerating self-consistent field iterations in Kohn-Sham density functional theory using a low rank approximation of the dielectric matrix

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    We present an efficient preconditioning technique for accelerating the fixed point iteration in real-space Kohn-Sham density functional theory (DFT) calculations. The preconditioner uses a low rank approximation of the dielectric matrix (LRDM) based on G\^ateaux derivatives of the residual of fixed point iteration along appropriately chosen direction functions. We develop a computationally efficient method to evaluate these G\^ateaux derivatives in conjunction with the Chebyshev filtered subspace iteration procedure, an approach widely used in large-scale Kohn-Sham DFT calculations. Further, we propose a variant of LRDM preconditioner based on adaptive accumulation of low-rank approximations from previous SCF iterations, and also extend the LRDM preconditioner to spin-polarized Kohn-Sham DFT calculations. We demonstrate the robustness and efficiency of the LRDM preconditioner against other widely used preconditioners on a range of benchmark systems with sizes ranging from \sim 100-1100 atoms (\sim 500--20,000 electrons). The benchmark systems include various combinations of metal-insulating-semiconducting heterogeneous material systems, nanoparticles with localized dd orbitals near the Fermi energy, nanofilm with metal dopants, and magnetic systems. In all benchmark systems, the LRDM preconditioner converges robustly within 20--30 iterations. In contrast, other widely used preconditioners show slow convergence in many cases, as well as divergence of the fixed point iteration in some cases. Finally, we demonstrate the computational efficiency afforded by the LRDM method, with up to 3.4×\times reduction in computational cost for the total ground-state calculation compared to other preconditioners.Comment: Accepted in Physical Review

    A study among the Gestational Diabetes Mellitus and Non-Gestational Diabetes Mellitus pregnant women highlighting the variations in lipid parameters attending ante natal clinics at Hi-Tech Medical College and Hospital, Bhubaneswar, Odisha, India

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    Background: Wide variation in the lipid profile in pregnancy is quite common. Exaggerated changes in insulin and lipid levels in women with GDM during pregnancy, lead to significant alterations in lipid levels in comparison to normal pregnancy. Lipid metabolism during pregnancy has a significant role to play in the aetiology and pathogenesis of GDM as is indicated by various studies previously.Methods: A hospital-based case control study was conducted at Hi-Tech Medical College and Hospital, Bhubaneswar, Odisha in the Department of Endocrinology. The sample size was 100 pregnant women. Study period was of one year from June 2018 to June 2019. In women of both the groups, i.e., with GDM and without GDM the mean age of presentation were 20-25 yrs. Out of the 100 cases, we took 50 patients of GDM in the cases group and 50 patients of non GDM pregnant women as control group. Fasting lipid profile was sent to the hospital laboratory analyzed by Tinder’s methods. The results thus obtained were analyzed using student ‘t’ test for statistical significance using SPSS version 20.Results: There was no statistical difference in age and parity between control and case group. Triglyceride (cases- 286.4±77.60 mg/dl) (controls-166±26mg/dl), total cholesterol (cases-256.5±41.7 mg/dl) (controls - 202.5±20.18mg/dl), VLDL (cases-53.4±13.2 mg/dl) (controls-46.6±13.1mg/dl) showed statistically significant values (p value0.5) among GDM and non GDM group. Lipid profile was performed predominately in women in II trimester.Conclusions: In comparison to non GDM women, it was observed that serum triglyceride, total cholesterol and VLDL level are significantly higher in woman with GDM. Whether lipid profile can be used as a predictor for gestational diabetes mellitus in future needs further research

    Large Scale Electronic Structure Studies on the Energetics of Dislocations in Al-Mg Materials System and Its Connection to Mesoscale Models

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    Computational modeling of dislocation behavior is vital for designing new lightweight metallic alloys. However, extraordinary challenges are posed by the multiscale physics ranging over a vast span of interacting length-scales from electronic-structure and atomic-scale effects at the dislocation core (<109rmm< 10^{-9} {rm m}) to long-ranged elastic interactions at the continuum scale (sim10upmusim 10 upmu). In particular, quantification of the energetics associated with electronic-structure effects inside the dislocation core and its interaction with the external macroscopic elastic fields have not been explored due to limitations of current electronic-structure methods based on the widely used plane-wave based discretization. This thesis seeks to address the above challenges by developing computational methodologies to conduct large-scale real-space electronic-structure studies of energetics of dislocations in Aluminum and Magnesium, and use these results to develop phenomenological connections to mesoscale models of plasticity like discrete dislocation dynamics (DDD), which study the collective behavior of the dislocations at longer length scales (simsim 1--15 upmuupmu). First, a local real-space formulation of orbital-free Density Functional Theory is developed based on prior work, and implemented using finite-element discretization. The local real-space formulation coupled with bulk Dirichlet boundary conditions enables a direct computation of the isolated dislocation core energy. Studies on dislocations in Aluminum and Magnesium suggest that the core-size---region with significant contribution of electronic effects to dislocation energetics---is around seven to eleven times the magnitude of the Burgers vector. This is in stark contrast to prior displacement field based core size estimates of one to three times the magnitude of the Burgers vector. Interestingly, our study further indicates that the core-energy of the dislocations in both Aluminum and Magnesium is strongly dependent on external macroscopic strains with a non-zero slope at zero external strain. Next, the computed dislocation core energetics is used to develop a continuum model for an arbitrary aggregate of dislocations in an infinite isotropic elastic continua. This model, which accounts for the core energy dependence on macroscopic deformation provides a phenomenological approach to incorporate the electronic structure effects into mesoscale DDD simulations. Application of this model to derive nodal forces in a discrete dislocation network, leads to additional configurational forces beyond those considered in existing DDD models. Using case studies, we show that even up to distances of 101510-15 nm between the dislocations, these additional configurational forces are non-trivial in relation to the elastic Peach-Koehler force. Furthermore, the core force model is incorporated into a DDD implementation, where significant influence of core force on elementary dislocation mechanisms in Aluminum such as critical stress of a Frank-Read source and structure of a dislocation binary junction are demonstrated. To enable the above electronic-structure studies of dislocations in generic material systems, calculations using the more accurate and transferable Kohn-Sham Density Functional Theory (KS-DFT) are required. The final part of this thesis extends previous work on real-space adaptive spectral finite-element discretization of KS-DFT to develop numerical strategies and implementation innovations, which significantly reduce the computational pre-factor, while increasing the arithmetic intensity and lowering the data movement costs on both many-core and heterogeneous architectures. This has enabled systematically convergent and massively parallel (demonstrated up to 192,000 MPI tasks) KS-DFT calculations on material systems up to sim100,000sim 100,000 electrons. Using GPUs, an unprecedented sustained performance of 46 PFLOPS (27.8% peak FP64 performance) is demonstrated on a large-scale benchmark dislocation system in Magnesium containing 105,080 electrons.PHDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/153417/1/dsambit_1.pd

    A CLINICAL STUDY ON MANAGEMENT OF STRESS IN TYPE -2 DIABETES MELLITUS (MADHUMEHA) WITH ASHWAGANDHA (WITHANIA SOMNIFERA)

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    Extensive worldwide research on diabetes has established the complexities of the relationship between stress and diabetes. Evidence suggests that stress can affect diabetes, in terms of both its onset and exacerbation. Stress can have a deleterious effect on glycaemic control and can affect quality of life in diabetics. On the other hand emerging evidence strongly suggests that interventions that help individuals prevent or cope with stress can have an important positive effect on quality of life and glycaemic control.In this clinical study we have approached to assess the different stresses like Emotional burden, Physician related distress, Regimen related distress &amp; Interpersonal distress in Type – 2 diabetic populations with Diabetes Distress Scale (DDS). Those diabetics having a considerable stress level (DDS Score &gt; 3) were given treatment with Ashwagandha (Withania somnifera) capsules for six weeks and once again their stress level was reassessed.Ashwagandha significantly reduced the stress level and other stress related complains along with a better glycemic control as compared to placebo without any adverse effect. The positive effect of the drug also continued for another six weeks even after withdrawing the medication.Therefore Ashwagandha can offer comprehensive benefits as an adjuvant in Type – 2 diabetics suffering from stress

    GSM Based Display ToolKit

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    Wireless communication has announced its arrival on big stage and the world is going mobile. We want to control everything and without moving an inch. This remote control of appliances is possible through Embedded Systems. The use of “Embedded System in Communication” has given rise to many interesting applications that ensures comfort and safety to human life. The main aim of the project will be to design a SMS driven automatic display toolkit which can replace the currently used programmable electronic display. It is proposed to design receive cum display toolkit which can be programmed from an authorized mobile phone. The message to be displayed is sent through a SMS from an authorized transmitter. The toolkit receives the SMS, validates the sending Mobile Identification Number (MIN) and displays the desired information after necessary code conversion. The system is made efficient by using ‘clone’ SIMs of same MIN in a geographical area so that the same SMS can be received by number of display boards in a locality using techniques of time division multiple access. Started of as an instantaneous News display unit, we have improved upon it and tried to take advantage of the computing capabilities of microcontroller. We envision a toolkit that will not only display message but also can be used to do some mechanical work

    Retrospective analysis of endoscopic retrograde cholangio pancreatography (ERCP) procedures in a tertiary care centre in coastal Odisha

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    Background: ERCP is commonly performed for radiologic visualisation and therapeutic procedure for treating various pancreatico-biliary disorders. There is no comprehensive data available till date about ERCP procedures from Odisha. The aim of this study was to review the indications and complications of endoscopic retrograde cholangiopancreatography (ERCP) procedures in a tertiary care centre in Odisha.Methods: From July 2013 to December 2016, consecutive patients undergoing ERCP procedure were included in the study. Patients with any previous papillary intervention like papillotomy, sphincterotomy or stent placement were excluded from the study. Patients’ demographic characters, ERCP indications and post-ERCP complications were reviewed.Results: Three hundred and fourteen patients were included in the study. Among them male patients were 161 and females were 153. Mean age was 50.75 years and the age range was 18 to 82 years. Most common indications for ERCP was malignant obstructive jaundice (N = 171, 54%) and choledocholithiasis (N = 137, 43.6%). Post ERCP complications developed in 25 patients (8%). Pancreatitis was the most common post-ERCP complication.Conclusions: ERCP is a safe procedure. ERCP complications in our centre are similar to those reported from other centres

    Vitamin D Deficiency Eradication: A National Priority

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    Vitamin D Deficiency Eradication: A National Priorit

    STAR (Survey for ManagemenT of DiAbetes with FibeR-rich Nutrition Drink): A Pan India Survey to Understand the Physician and Patient Perspective Regarding the Role of Dietary Fiber Supplement in the Management of Type 2 Diabetes

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    Objectives: The aim of the STAR survey was to understand the physicians’ knowledge, attitude and perception regarding the role of nutritional dietary fiber supplements in the daily management of type 2 diabetes mellitus (T2DM). It also aimed to compare the changes in glycemic parameters as well as energy and satiety levels between patients taking a high-fiber supplement and those not taking a fiber supplement. Methods: Two cross-sectional pan-India surveys were conducted. The first was among 152 physicians who had &gt;5 years of experience in treating patients with T2DM and treated &gt;50 patients with T2DM per month. A self-administered paper-based questionnaire was used for the survey. The other survey was conducted among 3,042 patients with T2DM who were receiving treatment with antidiabetics. These patients were further categorized into the Horlicks Diabetes Plus (HDP) group, which consisted of 1,524 patients who had consumed the HDP fiber supplement for a minimum of 3 months and the non-HDP group, which included 1,518 patients who had never consumed HDP. Results: Almost all physicians prescribed fiber-rich nutritional supplements to their patients with T2DM and believed that dietary fiber has an important role in managing glycated hemoglobin (HbA1c) values, healthy weight and cholesterol levels. Among the main benefits of HDP seen by physicians were improvement in satiety levels and increase in physical activity, reduction in HbA1c, fasting and postprandial glucose, and reduction in dose and/or number of hypoglycemic medications. All physicians recommended that it was important to increase awareness among patients as well as doctors regarding the benefits of HDP in patients with T2DM. Patients in the HDP group reported a mean decrease of 0.72 in their HbA1c value which was statistically significant at 3 months (8.04 at baseline to 7.32 at 3 months). In contrast, the non-HDP group showed a non-statistically significant decrease of 0.61 in HbA1c from a baseline value of 8.15. Furthermore, patients reported a significant decrease in weight of 3 kg in 3 months from baseline value of 72.11 kg to 69.11 kg. This reduction in weight was observed in 82% patients in the HDP group, while the non-HDP group showed an insignificant weight reduction from a baseline value of 72.14 kg to 71.46 kg in 3 months. About 83% of patients reported feeling full for longer periods of time and 92.62% reported feeling more energetic after starting HDP. The compliance and satisfaction rates with HDP were 96% and 75%, respectively. Conclusion: A high-fiber supplement taken along with patients’ existing antidiabetic treatment plan has the potential to decrease glycemic parameters and weight while increase the satiety and energy levels among patients with T2DM. However, these results need to be evaluated further with long-term clinical studies conducted in the real world.&nbsp
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