465 research outputs found
Minority carrier lifetime mapping of solar cells
Get PDFThe minority carrier lifetime distribution across silicon solar cells was investigated using variations of the open circuit voltage decay method. This was performed on monocrystalline, polycrystalline and amorphous silicon solar cells. Light from a white LED was focused using an aperture and a glass bi-convex lens to a spot size of 2mm on the surface of each cell investigated and moved in 1mm increments. At each point, a short pulse of light was emitted from the LED, with the open circuit voltage generated measured with time. This decay was then analysed using two calculation methods using a program written in LabVIEW. The generated minority carrier lifetime values at each point were exported in an array and plotted in Microsoft Excel, so that maps of the minority carrier lifetime were created.
The calculation method from Mahan et al. (Mahan et al. 1979), produced values of the minority carrier lifetime that were consistently lower than the results found using the method from Ranjan, Solanki and Lal (Ranjan, Solanki, and Lal 2008). The values of the minority carrier lifetime obtained in both instances were generally in the expected range, once abnormally high lifetimes found to be a result of external factors (such as increased background effects due to low LED intensities or measured open circuit voltages) were removed.
Due to the high levels of inaccuracy involved in analysis of the open circuit voltage decay curves, it was determined that this method could not produce reliable values of the minority carrier lifetime. However, through agreement of the two calculation methods used, the distribution of the minority carrier lifetime (such as regions of comparatively high and low lifetimes across a cell) could be determined with some accuracy in the case of the monocrystalline and polycrystalline silicon cells
Job satisfaction among health care workers in Block Shahapur, district Thane: An explorative study
No full textBackground: An organization is as strong and successful as its employees are. By measuring employee satisfaction in key areas, organizations can gain the information needed to improve their satisfaction, motivation, retention and productivity.
Objective: To assess the factors leading to job satisfaction among health care workers at Taluka Shahapur in district Thane in state of Maharashtra.
Methods: Four Focus group discussions were planned for 50 health care workers in Block Shahapur in district of Thane. Participation was on voluntary basis conducted during 5-10-2010 to 8-10-2010. 35 ANMs and 20 MPWs participated in four focus group discussions.
Result: 70% respondents were satisfied with their job. 80% respondents felt that their services are appreciated and acknowledged by the community73% respondents are not satisfied with their pay scale. 94% respondents are suspicious about the transparency of the system. Low monetary compensation, overburden of work due to vacancies, poorly defined job roles, poor non monetary rewards for achievements, poor participation in micro planning and decision making were mentioned as major stressors by most of the participants.
Conclusion: The study, however, is yielding a useful conclusion that some organizational transformation must be initiated at district and national level. To improve health care services in India, policy-makers need to consider the impact of current policies on job satisfaction in order to improve the efficiency of the system. Constant appraisal programs and appreciation should be instilled in the health care system to reinstate and motivate the employees
Investment protection a must in India-UK FTA
No full textThe India-UK investment relationship is no more a one-way street. In 2020, the stock of foreign direct investment from India in the UK was £10.6 billion as against £14.9 billion from the UK in India
A priori and a posteriori analysis of the hybrid two-level large-eddy simulation method for high Reynolds number complex flows
No full textWe present a priori and a posteriori analysis of the assumptions and predictions of the hybrid two-level large-eddy simulation (TLS-LES) method for high Reynolds number complex flows. The TLS-LES methodology is a multi-scale framework for simulation of turbulent flows in complex configurations at practically relevant Reynolds number. It additively combines the two-level simulation (TLS) model with a conventional large-eddy simulation (LES) approach by employing a static or dynamic blending function. In the present study, first we analyze the model assumptions employed by the TLS model to obtain the small-scale solution necessary for closure of the large-scale equations. Afterward, we analyze the large-scale and small-scale solutions to assess the predictive ability of the multi-scale framework for specific turbulence physics such as role of forward and backscatter of energy and presence of co- and counter-gradient diffusion. To perform these investigations, we consider cases with increasing degree of geometrical complexity, namely, flow in a periodic channel, flow past a bump placed on the lower surface of the channel and flow past a finite-span NACA0015 airfoil
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Texas Design Journal, Volume 1
Get PDFTable of Contents: ABOUT -- The Team / p. 01 -- Editors' Note / p. 03 -- IMMERSE -- Food Insecurity Among College Students / by Rohit Dinesh (p. 05) -- User Personas in Design Thinking / by Sean Feng (p. 08) -- Implication of NFTs on the Art Community / by Parth Ghawghawe (p. 11) -- Humanitarian AI and Vulnerable Populations / by Devina Parihar (p. 13) -- Making Sense of Chaos / by Eshna Parikh (p. 16) -- Student Experiences in Design / by Tanvi Shah (p. 20) -- Instructional Design / by Riya Solanki (p. 24) -- IDEATE -- Imagining the World of Engineering in Color / by Wis Escher (p. 28) -- Light the Way / by Ivy Lee (p. 30) -- Inclusive Multimodal Design / by Amy Li (p. 32) -- Austin Bus System Prototyping / by Corey Li (p. 34) -- Rethinking the Study Space Experience / by Neil Potnis (p. 36) -- PRODUCT ANALYSIS -- Understanding XR / by Celine Low (p. 42) -- Microtransactions in Gaming / by Bruce Luo (p. 44) -- Agile Development / by Ranjan Veludandi (p. 47) -- Robinhood: An Unworthy King / by Roger Zhong (p. 50) -- REFERENCES p. 53Undergraduate Studie
International Outsourcing Hurdles in Value-added Services
Get PDFPurpose: International Outsourcing has been traditionally looked upon as a low end cost effective servicing option to take advantage of the cost arbitrage that exists across countries. Of late, many outsourcing vendors have realized that the advantages of cost differentials that spurred a lot of the global outsourcing business in the past 20 years will disappear in the medium term. This paper provides a perspective about how much value addition, besides cost, traditional outsourcing vendors can provide and what may be the facilitator/ inhibitors of such activities. Approach: To substantiate the claim, a brief case describing the setting up of an offshore analytics operation is presented which gives a back drop to the challenges faced in relatively high end value creation processes in a remote outsourced environment. Findings/Claim: The author uses the case to develop a conceptual model of off shoring value –added services. The key dimensions that will determine the extent to which international outsourcing of high end services will take place are: 1) Expertise of the vendor, 2) Environmental Stability of the Outsourcing Domain, 3) Physical Barriers to outsourcing complex business processes such as, Communication Problems and Proximity issues, 4) Possibility of Knowledge Leakage from Outsourcing Domain and, 5) Cost Benefits of Outsourcing. Practical Implications: The author contends that conventional outsourcing vendors may find it difficult to acquire “Expert Power” and, set aside negative perceptions of “Environmental Stability” of their domain, in the pursuit to climb up the value chain in their client organizations. The validation of the proposed model is an opportunity for future research. Originality: This paper is one of the first to present a model that will govern the growth of international outsourcing opportunities in high end value-added processes.
Computational analysis of planar wings designed for optimum span-load
Get PDFA computational analysis of three span-optimized wings was conducted using an open-source CFD tool. Simulations were carried out at Rec = 450; 000 in a semi-spherical domain consisting of unstructured tetrahedra close to the wing surface and pyramids in the farfield region. Simulations were carried out in both steady state and semi-transient states to predict ow transition. A comparative study of different turbulence models revealed k-omega-SST and k - kL-omega to be the most suitable turbulence models for this study. The model accuracy was determined using validations with experimental data from a previous study. The required accuracy was achieved using the most appropriate mesh resolution for all three wing designs and second order discretization schemes. Computational results indicated different drag characteristics between the three span-load optimized wings at the design CL. The Viscous Optimized Wing produced the minimum drag while the Elliptic Wing produced the largest drag at design CL. The Inviscid Optimized Wing had the largest aspect ratio but still produced lesser drag when compared to the Elliptical Wing. Surface ow visualization indicated different ow transition characteristics for the three wings. These differences were attributed to the twist distributions specific to each wing. The Inviscid Optimized wing was observed to have largest laminar boundary-layer region at design angle of attack. Qualitative wake analysis indicated different wake characteristics for each wing, attributed to the different span-loads. The Elliptic Wing had the most aggressive wake roll-up. Much lesser wake roll-up was observed for the Inviscid and Viscous Optimized Wings. The largest wake cross-section was observed for the Elliptic Wing, while the smallest wake cross-section was observed for the Inviscid Optimized Wing.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-08-01The student, Prateek Ranjan, accepted the attached license on 2016-07-22 at 11:12.The student, Prateek Ranjan, submitted this Thesis for approval on 2016-07-22 at 11:25.This Thesis was approved for publication on 2016-07-22 at 16:28.DSpace SAF Submission Ingestion Package generated from Vireo submission #10076 on 2016-11-10 at 12:27:41Made available in DSpace on 2016-11-10T18:35:38Z (GMT). No. of bitstreams: 2
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Alignment Control for Optical Communication between Underwater Robots
No full textLight-emitting diode (LED)-based optical communication is emerging as a promising low-power, low-cost, and high-data-rate alternative to acoustic communication for underwater applications. However, it requires a close-to-line-of-sight (LOS) link between the communicating parties.Achieving and maintaining the LOS is challenging due to the constant movement of underlying mobile platforms caused by propulsion and unwanted disturbances. In this dissertation, a novel, compact LED-based wireless communication system with active alignment control is presented that maintains the LOS despite the movement of the underlying platform. Multiple alignment control algorithms are developed for scenarios that range from a simple one-way two-dimensional (2D) setting to a practical three-dimensional (3D) bi-directional underwater setting. An extended Kalman filter (EKF)-based approach is first proposed to estimate the relative orientation between the heading angle and the LOS direction, which is subsequently used for alignment control. The EKF uses only the measurement of light intensity from a single photo-diode, where successive measurements are obtained via a scanning technique that ensures the full observability of the underlying system. The approach is first examined in a 2D setting, and then extended to the 3D scenario with improvements in both the hardware and the algorithm. The amplitude of the scanning is modulated according to the alignment performance to achieve a sound trade-off between estimation accuracy, signal strength, and energy consumption. The efficacy of the approach is tested and verified via simulation and on an experimental setup involving two robots with relative 3D motion. The EKF approach uses an assumption that the relative motion between the robots is small, and consequently, requires the communicating robots to take the scanning in an alternating fashion for the convergence of the estimator. An alternative approach, first explored in the 2D setting, is developed that allows simultaneous, bi-directional alignment control for both parties. Because of the convex nature of the measured intensity functions, model-free approaches, including both hill-climbing (HC) and extremum-seeking (ES), are explored. The hill-climbing approach is found to be superior to the ES approach in terms of convergence time and computational efficiency. Theoretical analysis is provided for the hill-climbing approach that guarantees finite time convergence to an neighborhood of the LOS, for control step size .Finally, a model-free approach for the 3D setting is proposed that maximizes light intensity based on three consecutive intensity measurements from an equilateral triangle configuration. The efficacy of the approach is demonstrated experimentally, first with an underwater robot controlled by a joystick via LED communication and then with two robots performing bi-directional communication and tracking in an underwater setting.Thesis (Ph.D.)--Michigan State University. Electrical Engineering - Doctor of Philosophy, 2021Includes bibliographical reference
FDI Spillovers, Innovation and the Role of Industrial Clusters: Evidence from Innovative Indian Manufacturing Firms
No full text© 2025, Elsevier B.V. The attached document (embargoed until 08/09/2026) is an author produced version of a paper published in Economic Modelling uploaded in accordance with the publisher’s self-archiving policy. The final published version (version of record) is available online at the link. Some minor differences between this version and the final published version may remain. We suggest you refer to the final published version should you wish to cite from it
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