FE Analysis Of Flexural Bearing For Linear Compressor

Flexure bearing is a new concept and used for precision applications such as Programmable focusing mechanism (PFM), linear compressor etc. These bearings are compact and inexpensive. A flexure bearing is designed for specific applications. These designed can usually be done with the advanced design tool like FEA. With the advent of computers FEA has become the most suitable tool for the engineering analysis where the conventional approach is not suitable, geometric complexity are involved etc. This paper deals with the study of flexure bearings in linear compressor and makes theoretical analysis on it to calculate axial stiffness, radial stiffness and parasitic motion. Using software’s like CATIA and PROE ,modeling of flexure bearing done. Also make FEM analysis on it by using Ansys software. Then compare result of theoretical and FEM analysis. And lastly, this project considers the fatigue life criteria for flexure bearing and tries to optimize it. Gaurenkar have made design calculation and FE Analysis for flexure bearing to make appropriate model. This bearing contains three slots having 120° apart and 12 peripheral holes are used to clamp the disc rigidly onto a support structure. One central hole made for movement of shaft

Design and Implementation of Position Estimator Algorithm on Voice Coil Motor

Voice Coil Motors (VCMs) have been an inevitable element in the mechanisms that have been used for precise positioning in the applications like 3D printing., micro-stereolithography., etc. These voice coil motors translate in a linear direction and require a high accuracy position sensor that amounts for a major part in the budget. In this research work., an effort has been made to design and implement an algorithm that would predict the displacement of VCM and eliminate the need of high cost sensors. VCM was integrated with dSPACE DS1104 R&D controller via linear current amplifier (LCAM) which acts as a driver circuit for VCM. Sine input was given to VCM with various amplitude and frequency and the corresponding displacement is measured by using linear variable differential transformer (LVDT). The position estimator algorithm is also implemented at the same time on VCM and its output is compared with that of LVDT. It is observed that there is 97.8 % accuracy in between algorithm output and LVDT output. Further., PID controller is used in integration with the novel algorithm to minimize the error. The estimator algorithm is tested for various amplitudes and frequencies and it is found that it has a very good agreement of 99.2% with the actual displacement measured with the help of LVDT

Design, Development and Implementation of the Position Estimator Algorithm for Harmonic Motion on the XY Flexural Mechanism for High Precision Positioning

This article presents a novel concept of the position estimator algorithm for voice coil actuators used in precision scanning applications. Here, a voice coil motor was used as an actuator and a sensor using the position estimator algorithm, which was derived from an electro-mechanical model of a voice coil motor. According to the proposed algorithm, the position of coil relative to the fixed magnet position depends on the current drawn, voltage across coil and motor constant of the voice coil motor. This eliminates the use of a sensor that is an integral part of all feedback control systems. Proposed position estimator was experimentally validated for the voice coil actuator in integration with electro-mechanical modeling of the flexural mechanism. The experimental setup consisted of the flexural mechanism, voice coil actuator, current and voltage monitoring circuitry and its interfacing with PC via a dSPACE DS1104 R&D microcontroller board. Theoretical and experimental results revealed successful implementation of the proposed novel algorithm in the feedback control system with positioning resolution of less than ±5 microns at the scanning speed of more than 5 mm/s. Further, proportional-integral-derivative (PID) control strategy was implemented along with developed algorithm to minimize the error. The position determined by the position estimator algorithm has an accuracy of 99.4% for single direction motion with the experimentally observed position at those instantaneous states

Clinical study of ventilator-associated pneumonia in tertiary care hospital, Kolhapur, Maharashtra, India

Background: Ventilator‑associated pneumonia (VAP) is the most common nosocomial infection acquired by patients admitted in the intensive care unit (ICU). However, there is very less information or clinical data available on the occurrence of VAP in Kolhapur, Maharashtra.Methods: study aims to determine the Incidence of VAP in ICU, to study the association between causative microorganism and sensitivity, and to study the association between prognosis and incidence of VAP. Settings and Design: Tertiary level, medical‑surgical ICU; prospective, observational study.Results: Patients coming to Medicine Department of the hospital subjected to mechanical ventilation for more than 48 hours in critical Care Facility during the period of two years May 2014 to April 2016.Conclusions: In the incidence of VAP was found to be 78% among ICU patients. Majority (36%) patients had diabetes mellitus, 30% had hypertension before the admission. It is observed that chances of developing VAP were more in patients with co-morbid conditions. The microbiological results of Endotracheal Aspirate showed that, majority 36% had pseudomonas, 26% had Acinetobacter, 22% had no growth, 14% staphylococci (Staphylococcus is a gram-positive, round-shaped bacterium that is a member of the Firmicutes, and is frequently found in the nose, respiratory tract, and on the skin), 2% proteus mirabilis as compared to similar studies. Out of all, Pseudomonas is the most commonly isolated organism. This could be attributed to decreased immunity and a compromised general condition due to associated illness. Also, prolonged hospital stay is also of significance

Prescription audit of patients attendees in public health facilities in Maharashtra, India with special reference to rational use of antibiotics

Background: As soon as a doctor examines the patient, he/she writes the treatment for the illness on a piece of paper and that is called as “Prescription”. Prescription is a document through which doctor, patient and pharmacist are communicated to each other but many a times if these documents are not properly written or misinterpreted it can affect management of patients. World Health Organization (WHO) has established prescribing indicators to analyze the prescription and promoted rational use of drugs and better management of patients. Prescription audit captures the current practices and identifies opportunities for improvement in patient care and along with the mechanisms for realizing them. The main objective is to analyze the prescription of drugs given to the patients in OPD and IPD of the primary and secondary level public health facilities in Maharashtra.Methods: The study was a cross-sectional and observational based on both qualitative and quantitative data. It comprises of secondary data obtained from copies of prescription collected from selected Rural Hospitals (RHs)/Sub-district Hospitals (SDHs) and District Hospitals (DHs)/ Women Hospitals (WHs) of Maharashtra comprising on prescribing practice, rational use of drugs and antibiotics, patient care and facility specific indicators. The Prescribing patterns were analyzed using WHO guidelines with regard to prescribing, patient care and health facility indicators. Qualitative) data collected on perceptions of the patients attending OPD as regard of doctor's consultation and dispensing of medicine; as well as perceptions of pharmacists regarding working environment that measures the ability to prescribe drugs rationally. The copies of the prescriptions from the patients attending OPD / IPD at the above mentioned public health institutions (PHCs, RHs, SDHs and DHs/ DWHs) were obtained. Statistical analysis of study was analyzed using the frequencies and cross tabs by using MS-Office Excel and SPSS Version 20.Results: This exercise showed that there is a scope for improvement in prescribing patterns in areas of writing generic names of drugs, essential drugs, writing legible and complete prescriptions.Conclusions: The present study clearly indicates that there is a great need of interventions like distribution of antibiotic guidelines and running workshops and seminars on rational drug use to prescribers to improve the prescribing behaviour in the state of Maharashtra. This can be enforced through introducing such concepts and those of rational prescribing in curriculum of medical schools. E-prescriptions can be started in E-Aushadhi software with periodic clinical meetings to learn from the evidence.

Experimental study of effect of pressure on pyrolysis of biomass

Pyrolysis is thermal treatment of solid waste in the absence of an oxidizing agent (in inert atmosphere) which generally yields three products namely pyrolysis-oil (liquid), char (solid residue) and gas. The products obtained in pyrolysis can be further used as energy source. Rice husk and saw dust are considered as solid wastes in this study. The effect of temperature and pressure on pyrolysis was studied in a fixed bed reactor. The experimental runs were performed in nitrogen atmosphere. The temperature was varied from 300°C to 500°C, while the operational pressure was fixed at 4 bar, 7 bar and 10 bar. The products such as solid char, liquid pyrolysis oil and syngas were obtained. The solid char was characterized by CHNS analysis, while the pyrolysis oil was characterized by FTIR analysis

Characterization and System Identification of XY Flexural Mechanism Using Double Parallelogram Manipulator for High Precision Scanning

This article represents modeling of double parallelogram flexural manipulator derived from basic classical mechanics theory. Fourth order vibration wave equation is used for mathematical modeling and its performance is determined for step input and sinusoidal forced input. Static characterization of DFM is carried out to determine stiffness and force deflection characteristics over the entire motion range and dynamic characteristics is carried out using Transient response and Frequency response. Transient response is determined using step input to DFM which gives system properties such as damping, rise time and settling time. These parameters are then compared with theoretical model presented previously. Frequency response of DFM system gives characteristics of system with different frequency inputs which is used for experimental modeling of DFM device. Here, Voice Coil Motor is used as Actuator and optical encoder is used for positioning sensing of motion stage. It is noted that theoretical model is having 5% accuracy with experimental results. To achieve better position and accuracy, PID and LQR (Linear Quadratic Regulator) implementation was carried out on experimental model. PID gains are optimally tuned by using Ziegler Nichols approach. PID control is implemented experimentally using dSPACE DS1104 microcontroller and Control Desk software. Experimentally, it is observed that positioning accuracy is less than 5 μm. Further multiple DFM blocks are arranged for developing XY flexural mechanism and static characterization was carried out on it. The comparison of experimental and FEA results for X-direction and Y-direction is presented at end of paper

BLOOM: A 176B-Parameter Open-Access Multilingual Language Model

Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License

THE STUDY OF RIVER EXTRACTION TECHNIQUES AND METHODS USING REMOTE SENSING

In this paper, Methods and technology of river Extraction are studied. First DEM with K means, Hill Climbing, and Thresholding. Then different technics like NDWI, pixel-based (supervised and unsupervised) classification and object-based classification. Then a new water body extraction model was developed using the advantages of the OBIA and the NDWI. The need for this kind of method comes from the fact that it is hard for pixel-based classification methods and th NDWI method to separate water from another object that has a low albedo, and since it is impossible to separate them by their spectral differences, we have decided to include the NDWI within the object-based method