288 research outputs found
Development of a virtual reality milling machine for knowledge learning and skill training
No full textCurrent methods of training personnel on high cost machine tools involve the use of both classroom and hands on practical training. The practical training required the operation of costly equipment and the trainee has to be under close personnel supervision. The main aim of this project is to reduce the amount of practical training and its inherent cost, time, danger, personal injury risk and material requirements by utilising a virtual reality technology.
In this study, an investigation into the use of Virtual reality for training operators and students to use the Milling Machine was carried out. The investigation has been divided into two sections: first the development of Milling Machine in the 3D virtual environment, where the real machine was re-constructed in the virtual space.
This has been carried out by creating objects and assembling them together. The complete Milling machine was then properly modelled and rendered so it could be viewed from all viewpoints.
The second section was to add motion to the virtual world. The machine was made of functions as for the real machine. This was achieved by attaching Superscape Control Language (SCL) to the objects. The developed Milling machine allows the users to choose the material, speed and feed rate. Upon activation, the virtual machine will be simulated to carry out the machining process and instantaneous data on the machined part can be generated.
The results were satisfactory, the Milling Machine was modelled successfully and the machine was able to perform according to task set. Using the developed Virtual Model, the ability for training students and operators to use the Milling Machine has been achieved
Miriam Sampaio : Murmur
No full textThis publication stems from artist Sampaio’s residency at Centre de production Daïmõn in the fall of 2001. The resulting exhibition comprised photographs taken by the artist while in Portugal where she was researching her Judaic-Portuguese roots. Hashmi comments on this work in a personal and poetic text that includes many quotes from the artist. Texts in English and French. Biographical notes on artist and author. 2 bibl. ref
Investigation into coatings produced from nanoparticle blended feedstock for rotating equipment repair applications
No full textCoating of carbon steel with conventional and nano particle blended feedstock material is considered in relation to repair applications of rotating equipment. Gas Metal Arc Welding (GMAW) and Wire Arc Spray (WAS) processes are used to produce the coatings on carbon steel workpieces. The wire arc sprayed workpieces are heat treated at temperature similar to the operating temperature of hot-path components of power gas turbines. The microstructure and metallurgy of the workpieces are examined using the Scanning Electron Microscope (SEM), Optical Microscope, Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD). The indentation tests are carried out to assess the microhardness variation across the coatings. In the case of coatings produced by GMAW, it is found that fine structures are formed in the coating due to the presence of nano particles and they resulted in increased microhardness of the coatings. In the case of the wire arc sprayed workpieces, the formation of dimples like structure at the surface increases the surface roughness of the coatings. In addition, the microhardness of the resulting coating is significantly higher than that of the base material. The heat treatment does not alter the microstructure and microhardness of the coatings significantly
Investigation into laser re-melting of inconel 625 HVOF coating blended with WC
No full textHigh velocity oxy-fuel (HVOF) spraying of Diamalloy 1005 powders mixed with WC particles onto steel (304) is considered and laser re-melting of the resulting coatings is examined. Laser re-melting process is modeled to determine the melt layer thickness while temperature increase is formulated using the Fourier heating law. The morphological and metallurgical analyses prior and post laser re-melting process are carried out using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). X-ray diffraction (XRD) technique is used to determine the residual stress developed in the coating while the analytical formulation is adopted to predict the residual stress levels at the coating base material interface. The indentation tests are carried out to determine the Young’s modulus and fracture toughness of the coating prior to laser re-melting. Corrosion resistance of coating is measured using potentiodynamic polarization technique prior and post laser treatment process. The predictions of the melt layer thickness are in good agreement with experimental results. The presence of WC particles modifies temperature rise and its gradient in the coating while affecting the Young’s modulus, residual stress levels, and fracture toughness of the coating. The differences in the thermal properties of Inconel 625 powders and WC particles result in formation of small size cellular structure through polyphase solidification. WC dissolution in the central region of the large polycrystalline cells is observed due to the loss of carbon through carbonic gas formation. The results of corrosion tests prevail that significant improvement of corrosion resistance can be achieved after laser treatment process
Towards metal free counter electrodes for dye-sensitized solar cells
No full textThis thesis provides a technical overview of results from addressing the critical steps in preparing counter electrodes for dye-sensitized solar cells (DSC) on flexible substrates (mainly plastics) to pave the way towards low-cost DSCs. The aim was to develop low-temperature counter electrode inks and pastes that could be suitable for high volume manufacturing processes. A special focus was given on the mechanical stability (flexibility and adhesion) of the materials that were deposited through a low-temperature route.
Different low temperature inks and pastes based on carbon composites were tested as a replacement to expensive platinum nanoparticles based catalyst layer and showed good mechanical stability, comparable photovoltaic performance and low charge transfer resistance in complete dye-sensitized solar cells.
Indium doped tin oxide (ITO) layer that is normally used as a conductor on plastic substrates was successfully replaced with a single walled carbon nanotube (SWCNT) film deposited as a low-temperature curable ink on polyvinyl chloride (PVC) substrate. The SWCNT films exhibited remarkably good mechanical stability when subjected to bending and tape adhesion tests. Coating the film with a thin layer of conducting polymer poly (3, 4-ethylenedioxythiophene (PEDOT) increased its catalytic performance comparable to a reference platinum counter electrode.
Relevant to scaling up DSC preparation, a two way electrolyte filling method was studied as a means to suppress performance losses that occur due to non-homogenous distribution of electrolyte components. The method enhanced the photovoltaic performance of a segmented measurement cell by up to 42% compared to traditional one way filling of the electrolyte.
The aforementioned results provide pathways for the future development of robust flexible counter electrodes that can be beneficial especially from the perspective of high throughput roll-to-roll processing of flexible DSCs on polymer substrates
جامعات میں اردو تحقیق‘‘ مرتبہ ڈاکٹر رفیع الدین ہاشمی: تحقیق و تجزیہ’’
No full textDr Rafiuddin Hashmi is a very well-known scholar. His book ‘Jamia’at mein Urdu Tehqeeq’ (Urdu Research at Universities) has been acclaimed as a remarkable work for the guidance of research scholars and students alike. Hashmi Sahib’s book is a pioneering work that enlists thousands of dissertations written for PhD /M Phil degrees in Urdu at universities around the world. A labour of love, this book is packed with rare information. This article endeavours to add some information and corrects some errors that have crept into Hashmi Sahib’s work. While the author has paid glowing tributes to Hashmi Sahib for his remarkable work, he has added some new data too from which researchers may benefit
Healthcare Systems : three studies of patient management and policy change
No full textThesis: Ph. D. in Engineering Systems, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, 2018Cataloged from PDF version of thesis. "Doctor of Philosophy in Healthcare Systems: Management and Policy Research."Includes bibliographical references.For my PhD thesis, I conducted behavioral science research and wrote three first- author journal format papers, of which one paper has been published and the other two will be submitted to healthcare management journals after completion of my degree. All three papers introduce new information about either the cost or the behaviors of patients in local clinics, filling a gap in the healthcare system's management and policy literature. The first paper studies patients with diabetes who are non-adherent to scheduled appointments with physicians in a specialized diabetes clinic setting in Boston. I developed and introduced new and interesting ''technology comfort" measures and a "Smartphone usage" scale, to evaluate if patients would be able to use smart technologies for their disease self-management. This paper not only suggests that patients with diabetes could potentially benefit from using existing advanced technologies, but that new policies can be introduced to reduce the rate of diabetes patients' appointment-related non-adherence. The second paper examines the system of adherence or self-management in five areas ( diet, exercise, medications, doctor's appointments and regular glucose monitoring), revealing how it is correlated to emergency visits and patient lifestyle satisfaction. I analyze predictors of emergency room visits and propose potential policies to reduce these ER visits through the use of advanced smart technologies. The third paper identifies the incidence and consequences of not practicing non- pharmaceutical interventions, during the time of a pandemic, in a student population at a local university clinic.by Sahar Hashmi, MD.Ph. D. in Engineering SystemsPh.D.inEngineeringSystems Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Societ
Performance Evaluation Of Biosimulator For Treating Domestic Wastewater Using activated Sludge Treatment System
No full textThis research investigation was aimed at demonstrating the performance
evaluation of pilot activated sludge treatment system (biosimulator;
model MF-114). An intensive analytical program was followed for
evaluating the performance efficiency of the biosimulator by
maintaining the dissolved oxygen (DO) concentration at 4.0 mg/L
throughout the study period. Biosimulator performance was evaluated
after every 2 hours and analyzed for pH, DO, COD, ammonia-nitrogen
(NH3-N), nitrite-nitrogen (NO2-N) and nitrate-nitrogen (NO3-N). In all
ten experimental replicates were performed and the mean figures are
taken for discussion. Although no significant variation in the pH was
observed during the study period but the mean pH values of the samples
during the treatment process gradually increased and it ranged from
6.81-7.52. The removal of COD was found to be in direct relationship
with retention time and the mean COD of the raw wastewater samples
ranged from 164-1160 mg/L whereas it got reduced considerably during
the treatment process and the mean removal efficiency was found to be
86%. The COD and NO2-N removal efficiency was better than NH3-N and
NO3-N this is considered to be satisfactory especially with respect to
organic loading and retention time. Similarly, the mean NH3-N values of
wastewater after 29 hours of treatment were found to be fluctuating
between 14.52-20.54 mg/L whereas the mean NO3-N level of the raw
wastewater ranged from 0.106-0.279 mg/L. The overall conditions were
very much favorable even at high organic loading and minimum retention
time. It is therefore concluded that the system is practically feasible
for the treatment of wastewater containing high content of organic
matter
Nietzsche, Adorno, and the paradoxes of enlightenment
No full textThis thesis is a comparative study of Friedrich Nietzsche’s (1844-1900) and Theodor W. Adorno’s (1903-1969) paradoxical understandings of enlightenment. Distinguishing between the ahistorical process of enlightenment and the epoch of the Enlightenment, the thesis will show that both thinkers view enlightenment as a double-edged sword that has come to undermine itself. Far from leading people to new heights, Nietzsche and Adorno believe that enlightenment has enslaved humanity and produced a dry cultural life that is in urgent need of change. This analysis will identify a fundamental difference between Nietzsche’s and Adorno’s paradoxical understandings of enlightenment as they develop different models of enlightenment: Nietzsche’s is antithetical, and Adorno’s is dialectical. They maintain these understandings of enlightenment when writing on different topics, and the aesthetic and cultural spheres are important areas in which the paradoxes of enlightenment are on display. Their aesthetic thought includes examinations of artists. The most prominent of these common case studies is Richard Wagner (1813-1883), and Chapter Five of this study will highlight how Nietzsche and Adorno maintain their paradoxical understandings of enlightenment in a practical examination of art. However, neither Nietzsche nor Adorno gives up hope for a new kind of enlightened future. Both thinkers seek to reshape enlightenment by ridding it of what they think caused its downfall. For Nietzsche this process involves redressing what he considers to be an imbalance between reason and non-reason, which he states has removed vigour and vitality from human existence; and Adorno wishes to overcome instrumental reason and intellectual rigidity, which he believes have led to the establishment of a pernicious system of cultural and economic control. Enlightenment is not doomed, but it must be freed from the forces that have restricted its potential to liberate humanity
Domestic Wastewater Treatment Using Biosimulator (Activated Sludge Treatment System)
No full textAbstrac
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