Aggregation of particles in horizontally converging air motion

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Analytic and Machine Learning Based Design of Monolithic Transistor-Antenna for Plasmonic Millimeter-Wave Detectors

Department of Electrical EngineeringThis thesis reports an advanced analysis on a monolithic transistor-antenna by designing a ring-type asymmetric FET itself as a receiving antenna element which receives millimeter-waves in a loss-less manner with a plasmonic ampli fication for millimeter-wave (mmW) detectors. The proposed transistor-antenna device combines the plasmonic and the electromagnetic (EM) aspects in a single place. As a result, it can absorb the incoming mmW and transfer power directly to the ring-type asymmetric channel without any feeding line and a separate antenna element. Both the charge asymmetry in the device channel and the antenna coupling are contributing to the enhanced photoresponse. Among the two factors, the improved antenna coupling is more dominant in the performance enhancement of our proposed design. Also, our transistor-antenna device have enhanced performance with a uniformly enhanced responsivity of every pixel by characterizing its impedance exactly pursuing real-time mmW imaging. Operation principle of the proposed device is discussed, focusing on how signal transmission through the ring-type structure is available without any feeding line between the antenna and the detector. To determine the antenna geometry aiming for a desired resonant frequency, we present an efficient design procedure based on periodic bandgap analysis combined with parametric electromagnetic simulations. From a fabricated ring-type FET-based monolithic antenna device, we demonstrated the highly enhanced optical responsivity and the reduced optical noise-equivalent power, which are in comparable order with the reported state-of-the-art CMOS-based antenna integrated direct detectors. Another part of the thesis focuses on developing machine learning models to enable fast, accurate design and veri fication of electromagnetic structures. We proposed a novel Bayesian learning algorithm named as Bayesian clique learning, for searching the optimal electromagnetic design parameter by using the structural property of EM simulation data set. Along with this, we also given an inverse problem approach for designing the electromagnetic structures which suggest going in the opposite direction to determine the design parameters from characteristics of the desired output.clos

A survey of Trace Metals Determination in Hospital Waste Incinerator in Lucknow City, India

Information on the elemental content of incinerator burning of human organ, animal and medical waste is scanty in India Nineteen trace elements were analyzed in the incinerator ash from four major hospitals, one municipal waste incinerator and two R & D laboratories engaged in animal experiment in Lucknow city. Concentrations of Zinc and Lead were found to be very high in comparison to other metals due to burning of plastic products. The source of Ca, P and K are mainly bone, teeth and other animal organs. A wide variation in trace concentration of several toxic elements have been seen due to variation in initial waste composition, design of the incinerator and operating conditions

The validation of Swahili version of the international prostate symptom score questionnaire

Background: Benign prostatic hyperplasia is a common condition encountered in men who are 50 years and above, presenting in hospitals for evaluation of lower urinary tract symptoms. The International Prostate Symptom Score is one of the questionnaires used to assess these symptoms. However, this questionnaire has not yet been validated among patients with Benign Prostate Hypertrophy in the Tanzanian setting. Objectives: The primary objective of this study was to assess the validity of the Swahili version of the IPSS questionnaire among patients with benign prostatic hyperplasia. Methods: We employed a cross-sectional study design in patients that presented at the Aga Khan Hospital, Dar es Salaam, Tanzania with lower urinary tract symptoms. To validate our Swahili version of the International Prostate Symptom Score questionnaire validity and reliability were calculated. The validity of the questionnaire was established with face validity and discriminant validity. The reliability of the questionnaire was established by assessing the test-retest reliability and the internal consistency of the Swahili version of International Prostate Symptom Score questionnaire. The sensitivity to change was assessed using paired T- test. Correlation coefficients were presented in tables in the relevant domain. Results: There was excellent internal consistency observed between the Swahili International Prostate Symptom Score and the original International Prostate Symptom Score with a Cronbach’s α of 0.86 and 0.919 respectively. Test-retest reliability showed high inter class correlation of 0.84. The average improvement after treatment on the Swahili International Prostate Symptom Score was 9.69 ± 6.36. Conclusion: The Swahili International Prostate Symptom Score is reliable, valid and sensitive to change in the Tanzanian population

Incidence of coronary artery disease before valvular replacement in isolated severe aortic stenosis patients in Western Rajasthan

Background: The aim of the study was to evaluate the incidence of Coronary artery disease (CAD) and predictors of CAD in patients with severe AS in western Rajasthan population.Methods: Data from all consecutive patients with severe AS undergoing AVR at a major tertiary cardiac and vascular center in Udaipur were entered in a prospective registry beginning in 2015. Significant CAD was defined as one or more major coronary arteries having an estimated narrowing of ≥70% and left main coronary arteries having an estimated narrowing of ≥50% on coronary angiography. We excluded patients with multiple valve disease, significant aortic regurgitation, or prior CAD or valve surgery.Results: Mean age of 55 enrolled patients was 52.64±15.5 years. Diabetes mellitus and hypertension were present in 3.64% and 5.45% of patients, respectively. Moderate and severe Left ventricular ejection fraction (LVEF) was found in 16.36% and 10.91% patients, respectively. Only 5.45% patient had severe CAD and thus underwent AVR and coronary artery bypass grafting, and rest 94.55% patients underwent AVR. Mean age of patients who underwent AVR was 51.75±15.36 years and who underwent AVR and CABG was 68±11.14 years with no significant association (p=0.078). Proportion of patients requiring AVR and CABG was significantly higher in moderate (22.22%) and severe LVEF (16.67%) as compared to normal or mild (p=0.034).Conclusions: Coronary angiography before AVR will be considered in patients with multiple risk factors for cardiovascular disease or in patients above 68 years of age without risk factors for cardiovascular disease. However, larger studies on heterogeneous population are required to prove our findings.

State space formulation of TFEA & uncharted islands of instability in milling

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on January 7, 2008)Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2007.Dissertations, Academic -- University of Missouri--Columbia -- Mechanical and aerospace engineering.A new approach is developed to examine the stability of delay differential equations that builds upon the previous work in temporal finite element analysis. In contrast to the results of previous work, which could only be applied to second order delay differential equations, the present work is on developing an approach which can be applied to a broader class of systems that may be written in the form of a state space model. Conclusive evidence that isolated islands of chatter vibration can exist inthe stability charts of milling processes is provided. Modeling efforts consider the influence of the tool helix angle to obtain the aforementioned results and develop an analytical force model with three piecewise continuous regionsof cutting. Theoretical predictions are validated by a series of experimental tests that confirm the isolated island phenomenon

Fatal pulmonary embolism after middle ear surgery: a case report

Pulmonary thromboembolism is a complication of underlying venous thrombosis. Factors contributing to thrombus formation include venous stasis, hypercoagulable state, immobilisation, surgery and pregnancy. Authors present the challenges authors faced in diagnosing pulmonary embolism in a post-operative patient. 35-year-old female with complaint of decreased hearing for 2 years along with tinnitus and giddiness was admitted for stapedectomy. She also gave history of dyspnoea and pedal oedema one month back for which she was hospitalized and underwent investigations which were normal. Patient was discharged as her clinical symptoms improved. On postoperative day 5, she developed sudden dyspnoea after getting up and walking a few steps. Dyspnoea along with falling saturation and bradycardia progressed to cardiopulmonary arrest. Intensive care was started. Bilateral lower limb venous doppler showed deep venous thrombosis. Clinical diagnosis of pulmonary embolism was made, and patient was lysed with Tenecteplase 30 mg. Echocardiography showed signs of resolution of embolism after lysis, but gradually patient deteriorated and developed cardiogenic shock. Intra-aortic balloon pump was inserted via right femoral artery and inotropic support was continued. However, patient’s condition worsened, and she developed cardiopulmonary arrest the next day and could not be revived. Prevention of pulmonary embolism is a major clinical problem for which prophylactic measures like early ambulation in post-operative periods, elastic stockings, graduated compressive stockings for bed ridden patients and preventive anticoagulation therapy in high risk patients should be considered

Barrier inhomogeneities of Al/p-In2Te3 thin film Schottky diodes

The current-voltage (I-V) and capacitance-voltage (C-V) characteristics of p-In2Te3/Al thin films Schottky diodes papered by Flash Evaporation technique were measured in the temperature range 303-335 K have been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights (φbo) due to barrier height inhomogeneities that prevail at the interface. It has been found that the occurrence of Gaussian distribution of BHs is responsible for the decrease of the apparent BH (φbo) and increase of the ideality factor (η). The inhomogeneities are considered to have a Gaussian distribution with a mean barrier height of (φbm) and standard deviation (σs) at zero-bias. Furthermore, the activation energy value (φb) at T = 0 and Richardson constant (A**) value was obtained as 0.587 eV and 3.09 Acm– 2 K– 1 by means of usual Richardson plots. Hence, it has been concluded that the temperature dependence of the I-V characteristics of p-In2Te3/Al Schottky Diodes can be successfully explained on the basis of TE mechanism with a Gaussian distribution of the BHs. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2790

Multiphysics Simulation of Laser Cladding Process to Study the Effect of Process Parameters on Clad Geometry

AbstractThe present work reports two-dimensional simulation of laser cladding process to understand the influence of process parameters on clad geometry formation for better process optimization. The application deals with pure copper powder cladding of SS316L substrate for process feasibility for thicker coating layers by CO2 laser. For this purpose, first mathematical model is developed and dealt numerically using multi-physics software. Conservation equation of energy, momentum and mass of this process are coupled through the temperature variable and solved to adapt the laser cladding process. The boundary conditions due to the laser melting process of dissimilar materials have to be deal with complex assumptions are applied in mathematical modelling to simplify problem due to the different materials properties. The deformation of free surface is calculated using moving mesh by the way of ALE (Arbitrary Lagrangian and Eulerian) method. In addition, thermo-capillary forces and their effect on fluid flow inside the melt pool are also considered in modelling to complete the process optimization. Thermal and stress distributions due to the process are also evaluated in the developed process simulation. The results provide approximate information about the effect of each selected parameters on clad geometry formation. The influence of process parameters have shown the best choice of optimization