1,238 research outputs found
History of the Régiment of Artillery, Indian Army, éd. by Major-General D. K. Palit
No full textPouchepadass Jacques. History of the Régiment of Artillery, Indian Army, éd. by Major-General D. K. Palit. In: Revue française d'histoire d'outre-mer, tome 60, n°221, 4e trimestre 1973. p. 720
A novel hybrid shell element formulation (QUAD+ and TRIA+) : a benchmarking and comparative study
No full textThis paper introduces a novel hybrid finite element (FE) formulation of shell element to enable assembly process simulation of compliant sheet-metal parts with higher efficiency and flexibility. Efficiency was achieved by developing both new hybrid quadrilateral and triangular elements. Quadrilateral element (QUAD+) was formulated by combining area geometric quadrilateral 6 (AGQ6) nodes and mixed interpolated tensorial components (MITC) to model membrane and bending/shear component respectively. Triangular element (TRIA+) was formulated by merging assumed natural deviatoric strain (ANDES) for membrane and MITC for bending/shear component. Flexibility was addressed by developing an open-source C++ code, enhanced by the OpenMP interface for multiprocessing programming. Tests and benchmarks were compiled and executed within Matlab using the MEX API interface. Extensive benchmark studies were accomplished to evaluate the performance of the proposed hybrid formulation and the shell formulations used in three FEM packages - ABAQUS, ANSYS and COMSOL- under static linear elastic condition with small strain assumption. It was observed that the proposed QUAD+ and TRIA+ elements performed better amongst the FE packages, especially when there was in-plane mesh distortion, with errors below 3%. It was also identified that the best efficiency is obtained by adopting dominant QUAD+ elements compared to the TRIA+ when working on complex geometries. This paper also contributes to present a wide set of benchmark studies required to verify new release of FE packages using shell element or evaluate the performance of new shell formulations
Rapid Response Diagnosis of Multi-stage Assembly Process with Compliant non-ideal Parts using Self-evolving Measurement System
No full textThis paper introduces the novel concept of self-evolving measurement system with the aim of rapidly identifying and localising defect patterns in multi-stage assembly systems with compliant non-ideal parts. This allows to enhance the level of diagnosability which cannot be achieved using fixed and static pre-determined measurement systems. The proposed methodology helps to identify and select new measurement points to increase the likelihood of isolating root causes of defects. This happens by automatically classifying defect patterns and associating them to critical key control characteristics. The methodology integrates supervised machine learning tools with first principle engineering simulations. It is based on the principle of pattern similarity, taking into account data generated by the self-evolving measurement system. The methodology is demonstrated and validated using the results of an automotive door assembly system
A non-obtrusive technique to characterize dielectric charging in RF-MEMS capacitive switches
No full textDegradation and failure due to dielectric charging has been a dominant and pervasive reliability concern for RF-MEMS switches. Traditionally, the operational lifetime dictated by this degradation phenomenon is extrapolated from a series of measurements of time-dependent shifts in Capacitance-Voltage (C-V) characteristics under accelerated stress conditions. In this paper, we explain why the classical large-signal C-V methodology may lead to a pessimistic under-prediction of device lifetime. Using both simulations and experiments, we propose and verify a new small-signal characterization technique based on resonance characteristics of MEMS cantilever beams. This new technique overcomes the limitations of the classical approaches to accurately anticipate device lifetime and opens up the possibility of non-obtrusive, in-situ runtime monitoring of degradation in RF-MEMS switches. Moreover, since the technique is amenable to `parallel\u27 implementation, it has the potential to be used both as an in-line process monitor as well as to reduce the overall time to technology qualification
sj-pdf-1-pmj-10.1177_02692163241242647 – Supplemental material for How do people in prison access palliative care? A scoping review of models of palliative care delivery for people in prison in high-income countries
No full textSupplemental material, sj-pdf-1-pmj-10.1177_02692163241242647 for How do people in prison access palliative care? A scoping review of models of palliative care delivery for people in prison in high-income countries by Emma Gilbert, Nick De Viggiani, Joana de Sousa Martins, Tanuka Palit, Jessica Sears, Daniel Knights, Audrey Roulston, Mary Turner and Lucy E Selman in Palliative Medicine</p
Detailed computer modeling of semiconductor devices
No full textDetailed computer modeling to optimize the performance and design of semiconductor devices in general and of solar cells in particular
has become extremely popular over the last two decades. This is because, experimentally, such optimization involves a huge number of trials;
whereas the number of trials needed to optimize the performance of such semiconductor devices, can be decimated, using computer modeling, which
is nowadays therefore widely recognized as a tool for faster progress of such research. A detailed computer model, as opposed to simple analytical
models, is where the Poisson’s equation and the electron- and hole-continuity equations are all solved from the first principles, without resorting to
any simplifying assumptions. It is therefore, only such detailed models that are capable of giving an insight into device performance. Such models
become very complicated in the case of disordered semiconductors, where we also have to take into account the trapping and recombination kinetics
through the gap states. Moreover, in order to model both the electrical and optical properties of opto-electronic devices based on semiconductors in
their entirety, we also need to combine the electrical model with a suitable optical model, capable of calculating not only the absorption in each
portion of the device, but also the losses suffered by reflection or absorption in the non-active layers of the device. Moreover, diffused reflectance,
transmittance and absorption when the device is deposited on a textured or rough surface also need to be taken into account; as also specular
interference effects when the interfaces are flat. In this review, we will discuss a detailed electrical-optical model that is capable of modeling the
performance of a general n-layer device based on crystalline, amorphous, poly-, micro- or nano-crystalline semiconductor, with particular reference
to the modeling of opto-electronic devices, such as solar cells and color sensors.Author Affiliation: N Palit, U Dutta and P Chatterjee
1.Energy Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032, India
E-mail : [email protected] Research Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700 032, Indi
Technological Capability as a Determinant of FDI Inflows: Evidence from Developing Asia & India
No full textThis paper contributes to the empirical literature on determinants of FDI by addressing the question: Why do some developing countries from Asia continue to receive more FDI, while others from the region have fallen behind? It finds R&D-based innovative capacities, and the ability to apply such capacities through modern IT-based techniques, as the two key determinants explaining FDI inflows to developing Asian economies. These traits are found significant for inward FDI in India too with more technology intensive sectors receiving greater FDI. The findings of the paper suggest that in the absence of strong technological foundations and well-developed communications infrastructure, liberal policies alone are not enough for drawing FDI, once initial advantages, like cheap labour, fizzle out. For developing countries like India, strong thrust on R&D and innovative skills is needed for attracting FDI in technology-intensive exports. Therefore, policy actions would have to go further than a broad-based opening up of sectors to FDI, and increasing the limit of such investment in these sectors, for sustained inflows of FDI.FDI inflows, technology and technological capabilities, locational advantages, IT-based communication facilities
Technological Capability as a Determinant of FDI Inflows - Evidence from Developing Asia & India
No full textDuring 2006-07, FDI inflows into India were more than double than those in 2005-06. Indeed, during April-January 2006-07, inward FDI into India at US2-3 billion during the late 1990s. In recent years, India has also emerged as one of the leading FDI destinations in Asia. On the whole, the pattern of FDI inflows to developing Asia itself has changed significantly over the years. Some leading Southeast Asian economies (for example, Malaysia, Indonesia, Thailand and Philippines) no longer attract as much FDI as they used to in the past. Thisis in sharp contrast to some East and Southeast Asian economies that continue to draw large FDI (for example, China, Hong Kong and Singapore). In the above context, this paper attempts to explain the country-wise variations in the pattern of FDI flows to developing Asian economies by empirically identifying location specific features influencing such flows. The paper argues that some countries in the region, which have developed long term sources of comparative advantages in the form of superior technological capabilities and supporting infrastructure have consistently attracted greater volumes of export-oriented FDI. These attributes are also crucial for explaining the steady improvement in FDI flows to India. The paper finds that with production processes becoming increasingly complex and technology-intensive, developing countries like India, must devote greater attention to the development of R&D and frontier technologies, failing which, they might lose out in the race for FDI.FDI inflows, technology and technological capabilities, locational advantages, IT-based communication facilities
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