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Developing Successful Commercialisation Model Through Technology Transfer Assessing its Validity and Reliability by Using Structural Equation Modelling
Get PDFThe aim of this research is to develop and validate a suitable structural model for commercialization of successful innovations/ideas/methodology of R&D organizations through technology transfer. The survey data was extracted from 231 responses out of 310 target participants against the structured questionnaire containing 60 questions designed based on the literature survey. The factor structure and preliminary model are evaluated through Exploratory Factor Analysis. The first order and higher order Confirmatory Factor Analysis(CFA) models are evolved by estimating coefficients, covariance matrix, variances and performance indices. Structural Equation Modelling (SEM) is employed to develop and assess the validity and reliability of the structural model. The results implied that the developed structural model has achieved the required level of metrics and it can be implemented in to R&D organizations and industries for successful commercialization
Methodology for Application of Damage Mechanics Approach to Model High Temperature Fatigue Damage Evolution in a Turbine Disc Superalloy
Get PDFAeroengine gas turbine components operate under complex loading environments. Turbine disc is one such component which experiences stresses at high temperature and accumulates life critical cyclic damage in the material during usage. This accumulation of cyclic damage results into significant deterioration in material strength which in turn may initiate the failure in these rotating components. This necessitates the need to develop an advanced lifing approach for fatigue life assessment of turbine disc. As there are no available standards for damage mechanics application, an attempt has been made in the present study to develop a methodology for application of damage mechanics approach to model high temperature fatigue damage evolution in a turbine disc Superalloy. High temperature (650oC) stress-controlled fatigue tests on turbine disc alloy have been performed to evaluate parameters for damage mechanics based models. Using this approach, damage evolution has been simulated at specimen level. A good correlation has been observed in the damage mechanics based model’s predicted damage and experimentally determined values
Innovative Isostatic Processing Technologies for Defence and other Strategic Applications
Get PDFPowder Metallurgy (P/M) involving Cold Isostatic Pressing (CIP) and Hot Isostatic Pressing (HIP) techniques is the best suited processing route for manufacture of critical components from ceramics and highly complex metallic materials. The CIP followed by sintering route was adopted for the development of fused silica radomes for application in high-speed target seeking missiles. On the other hand, the HIP, a single-step processing technique has been used for the development of First-Wall (FW) of Test Blanket Modules (TBMs) from India Specific Reduced Activation Ferritic Martensitic (INRAFM) steel. The FW is an important component required for International Thermo-nuclear Experimental Reactor (ITER) application.The details of innovative processes which have been established to overcome the specific technical challenges for the development of CIP and HIP technologies for manufacture of silica radomes and INRAFM steel first-wall respectively for intended applications are highlighted in this paper
Effect of Temperature and Ply Angle on Performance of Ultra High Molecular Weight Polyethylene (UHMWPE) Laminates Under Low Velocity Impact
Get PDFLow velocity impact tests were conducted on ultra high molecular weight polyethylene (UHMWPE) laminates having different ply angle. The tests were conducted at various temperatures using steel impactor having 16mm diameter and hemi spherical shape. The selected impact energies are in the range of 50 to 250 Joule. The performance of the composites was compared with respect to peak force, maximum displacement and back face deformation. Results indicated that with increase of temperature, the contact duration increased whereas deceleration was reduced. Various failure mechanisms involved in energy absorption were also addressed
Simulation and Analysis of Electro Mechanical Actuator with Position Control
Get PDFIn recent times, Electro-Mechanical Actuator (EMA) is widely employed in various aerospace applications
because of its compactness, ease of maintenance, and cost efficiency. It attracts most of the researcher for simulation and performance analysis. It is very much important to study its control system behaviour. In general, EMA requires, three loop cascade control, but for aerospace application two loop cascade control is used for speed and position controls due to dynamic load changing requirement. Most research efforts on EMA system has used a transfer function model of all its subsystems. Nevertheless, this technique does not yield complete outcomes for analysing its performance. To analyse its performance and characteristics in dynamic condition, an experimental model is essential. In addition, this model needs to cater for analysing performance of different capacity EMA. The primary goal of this work is to simulate unique EMA model with position control using a practical data and analyse its performance. In this design, EMA is modelled by three-phase Brushless Direct Current (BLDC) motor, six-step commutation logic, a speed sensor (Tacho) and a position sensor using Linear Variable Differential Transformer (LVDT). Position and speed controls are handled by Proportional (P) and Proportional plus Integral (PI) controllers respectively. The process reaction curve method is used to tune the controllers. This tuning approach is adequate to enable accurate and robust speed and position control. This paper focus on the simulation and performance analysis of a practical EMA system with position and speed controls in matlab-simulink. The performance analysis results shows that simulated model characteristic is close to physical system and reliable
A Predictive Model with Data Scaling Methodologies for Forecasting Spare Parts Demand in Military Logistics
Get PDFThis study addresses the challenge of accurately forecasting demand for maintenance-related spare parts of the K-X tank, influenced by high uncertainty and external factors. Deep learning models with RobustScaler demonstrate significant improvements, achieving an accuracy of 86.90% compared to previous methods. RobustScaler outperforms other scaling models, enhancing machine learning performance across time series and data mining. By collecting eight years’ worth of demand data and utilising various consumption data items, this study develops accurate forecasting models that contribute to the advancement of spare parts demand forecasting. The results highlight the effectiveness of the proposed approach, showcasing its superiority in accuracy, precision, recall, and F1-Score. RobustScaler particularly excels in time series analysis, further emphasizing its potential for enhancing machine learning performance on diverse datasets. This study provides innovative techniques and insights, demonstrating the effectiveness of deep learning and data scaling methodologies in improving forecasting accuracy for maintenance spare parts demand
Microstructure and Mechanical Properties of Tungsten Heavy Alloy Prepared Using Tungsten Metal Powder Produced from Heavy Alloy Scrap
Get PDFTungsten metal powder, using a hydrometallurgical route, was extracted from tungsten heavy alloy scrap that was generated during machining of penetrator cores for the manufacture of Fin Stabilised Armour Piercing Discarding Sabot (FSAPDS). The powder was subjected to extensive characterisation that included physical property evaluation and analysis of the alloy chemistry in order to assess its suitability for the preparation of tungsten heavy alloys with enhanced mechanical properties. Subsequently, a tungsten heavy alloy based on W-Ni-Co was consolidated using this powder through liquid phase sintering followed by heat treatment and swaging operations to realize long rods (~500 mm). This was followed by a detailed characterisation that included microstructure and mechanical property. The mechanical properties of these rods are promising, exhibiting a good balance of tensile and impact properties, which in turn underscores the potential of these recycled powders in the production of premium quality heavy alloy long rods for stringent applications such as kinetic energy penetrators.
 
Adaptive Technique for Contrast Enhancement of Leading Vehicle Tracks
Get PDFDuring movement in various unpaved terrain conditions, the track impressions left over by the leading vehicles provide guiding and safe routes in the area. The delineation of these tracks captured by the images can extend immense support for guidance in real time. These tracks that look like edges in coarse-resolution images take the shape of elongated areas in fine-resolution images. In such a scenario, the high pass and edge detection filters give limited information to delineate these tracks passing through different surroundings. However, the distinct texture of these tracks assists in the delineation of these tracks from their surroundings. Gray level co-occurrence matrix (GLCM) representing the spatial relation of pixels is employed here to define the texture. The authors investigated the influence of different resolutions on the distinguishability of these tracks. The study revealed that texture plays an increasing role in distinguishing objects as the image resolution improves. The texture analysis extended to investigate the track impressions left over by the leading vehicle brings out an ample scope in delineating these tracks. The measures could improve the track contrast even better than conventional techniques. To select the most optimal contrast enhancement measure in a given scenario, authors proposed a quantified measure of track index. An investigation is made on the difference-based track index (TI) representing the mean contrast value of the track vis-à-vis off-track areas. The results show an increase in the quantified contrast from 7.83 per cent to 29.06 per cent. The proposed technique highlights the image with the highest track contrast in a given scenario. The study can lead to onboard decision-making for the rut following vehicles moving in low-contrast terrain
A Theoretical Approach in the Design of Single Frame 28 V DC and 270 V DC Dual Voltage Generator
Get PDFArmored Fighting Vehicles (AFVs) generally operate with a 28 V DC electrical system. However, the demand for electrical power in AFVs has exceeded the capabilities of the existing 28V system. The additional load growth necessitates larger wire sizes, which adds extra weight and cost to the vehicle. Introducing a dual-bus architecture (28 V DC and 270 V DC) can lead to the efficient operation of the electrical system while meeting future demand. This paper presents the design of a Brushless Direct Current (BLDC) Dual Voltage Generator (DVG), which simultaneously outputs two voltages (28 V DC & 270 V DC) from a single frame across a wide operational speed range. The design process includes a detailed description of the individual stages, accompanied by analytical parameters and software-generated results. The modeling and analysis of the generator were carried out using Motorsolve design software. The obtained results are presented and thoroughly discussed in this paper
Development and Airworthiness Certification of the Ti6Al4V Inlet Casing Inner Forging
Get PDFThe inlet casing inner has manufactured using Ti-6Al-4V alloy through a closed die-forging route. It undergoes cyclic loads in addition to operating in extreme conditions in high-temperature environments. The demanding mission requirement of these engines necessitates the inlet casing inner to be flawless throughout its life cycle while retaining its structural integrity. It makes the qualification for airworthiness of the casing, a daunting task. In addition, the qualification tests also help to evaluate the design and manufacturing processes (closed die forging) of the inlet casing inner. The tests also provide data for further improvement of the inlet casing inner in terms of strength and fatigue life. It helps to ensure that the inlet casing inner will be able to perform as expected throughout its operational life. All the batch and consolidated test results comply with the relevant ASTM, MIL standards, and test schedule requirements