Search results for: Abhishek Banerjee

Authors: Abhishek Mangal, Kunal Tongaria, S. Mandal, Devendra Mohan

Abstract:

Carbonation of reinforced concrete structures has emerged as one of the major challenges for Civil engineers across the world. With increasing emissions from various activities, carbon dioxide concentration in the atmosphere has been eve rising, enhancing its penetration in porous concrete, reaching steel bars and ultimately leading to premature failure. Several literatures have been published dealing with the various interdependent variables related to carbonation. However, with innumerable variability a generalization of these data proves to be a troublesome task. This paper looks into this carbonation anomaly in concrete structures caused by various external variables such as relative humidity, concentration of CO2, curing period and ambient temperature. Significant discussions and comparisons have been presented on the basis of various studies conducted with an aim to predict the depth of carbonation as a function of these multidimensional parameters using various numerical and statistical modelling techniques.

Keywords: carbonation, curing, exposure conditions, relative humidity

Procedia PDF Downloads 254

Authors: Abhishek Priyam, Prabha Chand

Abstract:

Channel depth is an important design parameter to be fixed in designing a solar air heater. In this paper, a mathematical model has been developed to study the influence of channel duct on the thermal performance of solar air heaters. The channel depth has been varied from 1.5 cm to 3.5 cm for the mass flow range 0.01 to 0.11 kg/s. Based on first law of thermodynamics, the channel depth of 1.5 cm shows better thermal performance for all the mass flow range. Also, better thermohydraulic performance has been found up to 0.05 kg/s, and beyond this, thermohydraulic efficiency starts decreasing. It has been seen that, with the increase in the mass flow rate, the difference between thermal and thermohydraulic efficiency increases because of the increase in pressure drop. At lower mass flow rate, 0.01 kg/s, the thermal and thermohydraulic efficiencies for respective channel depth remain the same.

Keywords: channel depth, thermal efficiency, wavy fin, thermohydraulic efficiency

Procedia PDF Downloads 372

Authors: Shubham Banerjee

Abstract:

The paper focuses on, how the business model of the Indian multi brand ecommerce industry is unstable and is headed towards an e-commerce bubble burst. Due to multiple players in the industry and little or no product differentiation, the Indian multi brand ecommerce industry has turned into an oligopoly market where there is hardly any brand loyalty of the customers. Companies have been rapidly increasing their selling cost in the forms of discounts and advertisements to retain and grow its customer base. This is resulting into higher revenues, but is driving the companies further away from their break-even point. With close to half a decade into the industry, none of the companies have been able to generate profits. With private investors losing patience and devaluing companies, the paper will throw light on how the multi brand e-commerce industry will change in the coming years.

Keywords: bubble burst, finance, multi brand ecommerce, product differentiation, private investor

Procedia PDF Downloads 286

Authors: Shiva Subhedar, Abhishek Jain, Shivin Mittal

Abstract:

Icons are not merely decorative elements in enterprise applications but very often used because of their many advantages such as compactness, visual appeal, etc. Despite these potential advantages, icons often cause usability problems when they are designed without consideration for their many potential downsides. The aim of the current study was to examine the effect of articulatory distance – the distance between the physical appearance of an interface element and what it actually means. In other words, will the subject find the association of the function and its appearance on the interface natural or is the icon difficult for them to associate with its function. We have calculated response time and quality of identification by varying icon concreteness, the context of usage and subject experience in the enterprise context. The subjects were asked to associate icons (prepared for study purpose) with given function options in context and out of context mode. Response time and their selection were recorded for analysis.

Keywords: HCI, icons, icon concreteness, icon recognition

Procedia PDF Downloads 258

Authors: Abhishek Jha, Manoj Kumar

Abstract:

This paper proposes a new type of two wheels differential type odometry to estimate the next position and orientation of mobile robots. The proposed odometry is composed for two independent wheels with respective encoders. The two wheels rotate independently, and the change is determined by the difference in the velocity of the two wheels. Angular velocities of the two wheels are measured by rotary encoders. A mathematical model is proposed for the mobile robots to precisely move towards the goal. Using measured values of the two encoders, the current displacement vector of a mobile robot is calculated by kinematics of the mathematical model. Using the displacement vector, the next position and orientation of the mobile robot are estimated by proposed odometry. Result of simulator experiment by the developed odometry is shown.

Keywords: mobile robot, odometry, unicycle, differential type, encoders, infrared range sensors, kinematic model

Procedia PDF Downloads 452

Authors: Susmita Panda, Arnab Banerjee, Ajinkya Baxy, Bappaditya Manna

Abstract:

The design of short to medium-span high-speed bridges in critical locations is an essential aspect of vehicle-bridge interaction. Due to dynamic interaction between moving load and bridge, mathematical models or finite element modeling computations become time-consuming. Thus, to reduce the computational effort, a universal approximator using an artificial neural network (ANN) has been used to evaluate the dynamic response of the bridge. The data set generation and training of surrogate models have been conducted over the results obtained from mathematical modeling. Further, the robustness of the surrogate model has been investigated, which showed an error percentage of less than 10% with conventional methods. Additionally, the dependency of the dynamic response of the bridge on various load and bridge parameters has been highlighted through a parametric study.

Keywords: artificial neural network, mode superposition method, moving load analysis, surrogate models

Procedia PDF Downloads 100

Authors: Abhishek Priyam, Prabha Chand

Abstract:

A theoretical investigation on the effect of collector aspect ratio on the thermal performance of wavy finned absorber solar air heaters has been performed. For the constant collector area, the various performance parameters have been calculated for plane and wavy finned solar air heaters. It has been found that the performance of wavy finned solar air heater improved with the increase in the collector aspect ratio. The performance of wavy finned solar air heater has been found 30 percent higher than those of plane solar air heater. The obtained results for wavy fin solar air heaters are compared with the available experimental data of most common type solar air heaters.

Keywords: wavy fin, aspect ratio, solar air heater, thermal efficiency, collector efficiency factor, temperature rise

Procedia PDF Downloads 329

Authors: Indrajeet Singh, Abhishek Gandhi, Smita Mohanty, S. K. Nayak

Abstract:

In this article, a focused study has been performed to comprehend the influence of change in depressurization rate on microcellular polycarbonate foamed morphological attributes. The depressurization rate considered in this study were 0.5, 0.05, 0.01 and 0.005 MPa/sec and the physical blowing agent utilized was carbon dioxide owing to its high solubility in polycarbonate at room temperature. The study was performed on two distinct saturation pressures, i.e., 3 MPa and 6 MPa to understand if saturation pressure has any effects on it. It is reported that with increase in depressurization rate, a higher amount of thermodynamic instability was induced which resulted in generation of larger number of smaller sized cells. This article puts forward an understanding of how depressurization rate control could be well exploited during the batch foaming process to develop high quality microcellular foamed products with exceedingly well controlled cell size.

Keywords: depressurization, porous polymer, foaming, microcellular

Procedia PDF Downloads 258

Authors: Meghana Pandit, Abhishek Chakraborty

Abstract:

There are a multitude of factors that influence the clinical success of bariatric surgery. This study seeks to determine the efficacy of preoperative weight management education. The Food and Fitness Program at Mount Sinai serves to educate patients on topics such as stress management, sleep habits, body image, nutrition, and exercise 5-6 months before their surgeries to slowly decrease their weight. Each month, patients are weighed, and a different topic is presented. To evaluate the longitudinal effects of these lectures, patient’s weights are evaluated at the first appointment, before an informative lecture is presented. Weights are then reevaluated at the last appointment before the surgery. The weights were statistically analyzed using a paired t-test and the results demonstrated a statistically significant difference (p < .0001, n=55). Thus, it is reasonable to conclude that the education paradigm employed successfully empowered patients to maintain and reduce their gross BMI before clinical intervention.

Keywords: bariatric, surgery, weight, education

Procedia PDF Downloads 135

Authors: M. L. McLain, R. Sreelakshmi, Abhishek, Rajeshwaran, Bhavani Rao, Kamal Bijlani, R. Jayakrishnan

Abstract:

Technology enhanced learning has brought drastic changes in the field of education in the modern world. In this study we explore a novel way to improve how high school students learn by building a serious game that uses a pedagogical model developed by Robert Gagne. By integrating serious game with principles of Gagne’s learning model can provide engaging and meaningful instructions to students. The game developed in this study is a waste sorting game that can easily and succinctly demonstrate the principles of this learning model. All the tasks in the game that the player has to accomplish correspond to Gagne’s “Nine Events of Learning”. A quiz is incorporated in order to get data on the progress made by the player in understanding the concept and as well as to assess them. Additionally, an experimental study was conducted which demonstrates that game based learning using Gagne’s event is more effective than a traditional classroom setup.

Keywords: game based learning, sorting and recycling of waste, Gagne’s learning model, e-Learning, technology enhanced learning

Procedia PDF Downloads 632

Authors: Arthi Ganapathy, Arithra Banerjee, Saroj Kaler

Abstract:

Abdominal aorta is the sole purveyor of all organs in the abdomen. Anomalies of its main trunk or its branches are to be meticulously observed as it effects the perfusion of an organ. Varying patterns of the testicular artery is one of them. The origin and course of testicular arteries have to be identified carefully during various surgical procedures like renal transplant, intra abdominal surgeries and even in orthopedic surgery like spine surgery. With the advent of new intra-abdominal therapeutic and diagnostic techniques, the anatomy of testicular arteries has assumed much more significance. Though the variations of the testicular vein are well documented, the variations of the testicular artery are not so frequent in incidence. We report a case of the bilateral aberrant origin of the testicular artery from polar renal arteries. We also discuss its developmental basis. Such anomalies if left unnoticed will lead to serious intraoperative complications during procedures on retroperitoneal organs. Any damage to testicular arteries will compromise the function of the gonads.

Keywords: cadaver, gonadal, renal, surgery

Procedia PDF Downloads 226

Authors: G. K. Pandey, D. Ramadasu, I. Banerjee, V. Vinod, G. Padmakumar, V. Prakash, K. K. Rajan

Abstract:

Detailed thermal hydraulic investigations are very essential for safe and reliable functioning of liquid metal cooled fast breeder reactors. These investigations are further more important for components with complex profile, since there is no direct correlation available in literature to evaluate the hydraulic characteristics of such components directly. In those cases available correlations for similar profile or geometries may lead to significant uncertainty in the outcome. Hence experimental approach can be adopted to evaluate these hydraulic characteristics more precisely for better prediction in reactor core components. Prototype Fast Breeder Reactor (PFBR), a sodium cooled pool type reactor is under advanced stage of construction at Kalpakkam, India. Several components of this reactor core require hydraulic investigation before its usage in the reactor. These hydraulic investigations on full scale models, carried out by experimental approaches using water as simulant fluid are discussed in the paper.

Keywords: fast breeder reactor, cavitation, pressure drop, reactor components

Procedia PDF Downloads 463

Authors: Anuradha Banerjee

Abstract:

Energy aware operation is one of the visionary goals in the area of robotics because operability of robots is greatly dependent upon their residual energy. Practically, the tasks allocated to robots carry different priority and often an upper limit of time stamp is imposed within which the task needs to be completed. If a robot is unable to complete one particular task given to it the task is reallocated to some other robot. The collection of robots is controlled by a Central Monitoring Unit (CMU). Selection of the new robot is performed by a fuzzy controller called Task Reallocator (TRAC). It accepts the parameters like residual energy of robots, possibility that the task will be successfully completed by the new robot within stipulated time, distance of the new robot (where the task is reallocated) from distance of the old one (where the task was going on) etc. The proposed methodology increases the probability of completing globally assigned tasks and saves huge amount of energy as far as the collection of robots is concerned.

Keywords: energy-efficiency, fuzzy-controller, priority, reallocation, task

Procedia PDF Downloads 316

Authors: Arnab Banerjee, Deep Sagar Verma

Abstract:

Tier 3 cities of India is home to one of the fastest growing socio-economic powers in the world and hence is the focus of a lot of business activity as it is almost a blue ocean giving the first mover a huge strategic advantage. Among the various sectors, the retailing is perhaps one of the most promising sectors. The study caries out 129 successfully structured mall-intercept interviews in the town of Shillong, Meghalaya in an attempt to understand the SBO and MBO shoppers. Demographic variables itself does not show any store format preference although discounts do attract the lower income group more while clear difference is observed among genders when it comes to importance of ambience, and it is more pronounced for SBO patrons. SBO patrons are more focused while MBO patrons are more into leisure shopping. Price is the most important predictor of satisfaction especially for MBO shoppers. The market shows three basic segments i.e experiential, relationship and value shoppers.

Keywords: demographic variables, degree of importance, degree of satisfaction, SBO and MBO

Procedia PDF Downloads 290

Authors: Prachi Abhishek Dave, Manisha Singh

Abstract:

Purpose: The purpose is to study the microbiological profile, prognostic factors, and outcomes of surgery for microbial keratitis (MK) associated endophthalmitis. Methods: It is a retrospective analysis of 39 MK associated endophthalmitis cases which underwent combined PKP with VR surgery. Results: The majority (84.6%) of patients had a history of previous ocular surgery, cataract surgery being the most common (51.2%). Six patients had a history of trauma and 8 patients had corneal graft infection. The culture positivity rate was 92.3%. Organisms isolated were Streptococcal sp (20.5%), Pseudomonas (15.3%), Staphylococcal sp (12.8%) and Fungus (35.8%). Final visual acuities ranged from NPL to 20/120. Poor anatomic success was seen in 15(38.46%) eyes (9-phthisis, 6-eviscerated). Fungal cases had a poor success rate (P-0.02). Conclusion: MK associated endophthalmitis is a sight threatening ocular condition. Fungal etiology carries a poorer prognosis. Timely surgical intervention can achieve favourable anatomical and functional results.

Keywords: endophthalmitis, microbial keratitis, penetrating keratoplasty, vitreo retinal surgery

Procedia PDF Downloads 49

Authors: Umesh Kumar Singh, Abhishek Raghuvanshi, Suyash Kumar Singh

Abstract:

As IoT networks gain popularity, they are more susceptible to security breaches. As a result, it is crucial to analyze the IoT platform as a whole from the standpoint of core security concepts. The Internet of Things relies heavily on wireless networks, which are well-known for being susceptible to a wide variety of attacks. This article provides an analysis of many techniques that may be used to identify vulnerabilities in the software and hardware associated with the Internet of Things (IoT). In the current investigation, an experimental setup is built with the assistance of server computers, client PCs, Internet of Things development boards, sensors, and cloud subscriptions. Through the use of network host scanning methods and vulnerability scanning tools, raw data relating to IoT-based applications and devices may be collected. Shodan is a tool that is used for scanning, and it is also used for effective vulnerability discovery in IoT devices as well as penetration testing. This article presents an efficient mitigation plan for encountering vulnerabilities in the Internet of Things.

Keywords: internet of things, security, privacy, vulnerability identification, mitigation plan

Procedia PDF Downloads 41

Authors: Probir Kumar Banerjee

Abstract:

Though the revised DeLone and McLean (DM) model of IS success is found to be effective at the individual level of analysis, there is lack of consensus in regard to its effectiveness at the organisational level. This research reviews the DM model in the light of business/IT alignment theory and supporting literature, and suggests its reconceptualization. Specifically, arguments are made for augmenting it with business process quality. Business process quality, it is argued, captures the effect of intent to use, use and user satisfaction interactions, thus eliminating the need to capture their interaction effects in explaining organisational IS success. It is also argued that ‘operational performance’ driven by systems and business process quality, and higher order measures of organisational performance tied to operational performance are appropriate measures of ‘net benefit’. Suggestions are made for reconceptualisation of the other constructs and an adapted model of organisational IS success is proposed.

Keywords: organisational IS success, business/IT alignment, systems quality, business process quality, operational performance, market performance

Procedia PDF Downloads 396

Authors: Sumit Banerjee, Chandan Kumar Chanda

Abstract:

The paper presents allocation of active power losses and energy losses to consumers connected to radial distribution networks in a deregulated environment for loads of composite types. A detailed comparison among four algorithms, namely quadratic loss allocation, proportional loss allocation, pro rata loss allocation and exact loss allocation methods are presented. Quadratic and proportional loss allocations are based on identifying the active and reactive components of current in each branch and the losses are allocated to each consumer, pro rata loss allocation method is based on the load demand of each consumer and exact loss allocation method is based on the actual contribution of active power loss by each consumer. The effectiveness of the proposed comparison among four algorithms for composite load is demonstrated through an example.

Keywords: composite type, deregulation, loss allocation, radial distribution networks

Procedia PDF Downloads 287

Authors: Debarag Banerjee, Pooja Singh, Arjun Avadhanam, Saksham Srivastava

Abstract:

Autonomous conversational agents, i.e., chatbots, are becoming an increasingly common mechanism for enterprises to provide support to customers and partners. In order to rate chatbots, especially ones powered by Generative AI tools like Large Language Models (LLMs), we need to be able to accurately assess their performance. This is where chatbot benchmarking becomes important. In this paper, authors propose the use of a benchmark that they call the E2E (End to End) benchmark and show how the E2E benchmark can be used to evaluate the accuracy and usefulness of the answers provided by chatbots, especially ones powered by LLMs. The authors evaluate an example chatbot at different levels of sophistication based on both our E2E benchmark as well as other available metrics commonly used in the state of the art and observe that the proposed benchmark shows better results compared to others. In addition, while some metrics proved to be unpredictable, the metric associated with the E2E benchmark, which uses cosine similarity, performed well in evaluating chatbots. The performance of our best models shows that there are several benefits of using the cosine similarity score as a metric in the E2E benchmark.

Keywords: chatbot benchmarking, end-to-end (E2E) benchmarking, large language model, user centric evaluation.

Procedia PDF Downloads 67

Authors: Abhishek Dave, Manisha Singh

Abstract:

Purpose: The study aims to evaluate the outcomes of combined Penetrating keratoplasty (PKP) and Vitreo-Retinal (VR) surgery in patients having endophthalmitis with poor corneal clarity. Methods: PKP with VR Surgery was performed in 43 eyes. This is a retrospective analysis of their preoperative, intraoperative and microbiological characteristics and anatomical and functional outcomes. Results: Corneal opacification was due to corneal ulcer in 30 (69.7%), graft infection in 8 (18.6%), bullous keratopathy in 4 and corneal scar in 1 eye. Postoperative visual acuity improved in 20 (46.5%), not changed in 14 (32.5%) and deteriorated in 9 eyes (20.9%). Poor anatomic success was seen in 15 (34.88%) eyes (9-phthisis bulbi, 6-eviscerated). Graft remained clear in 24 eyes (1 year). Microbiology revealed bacteria in 26, fungus in 14 and no growth in 3 eyes. Six out of 11 patients having poor vision in the fellow eye, too, achieved functional success. Conclusion: PKP with VR surgery is a complex but globe-salvaging procedure for poor prognosis eyes, which otherwise would need evisceration.

Keywords: penetrating keratoplasty, VR surgery, endophthalmitis, corneal ulcer

Procedia PDF Downloads 51

Authors: M. Riaz, Inamur Rehman, Abhishek Sharma

Abstract:

The present work is the development of an experimental method for determining the thermal diffusivity variations with temperature of selected regular shaped solid fruits and vegetables subjected to forced convection cooling. Experimental investigations were carried on the sample chosen (potato and brinjal), which is approximately of spherical geometry. The variation of temperature within the food product is measured at several locations from centre to skin, under forced convection environment using a deep freezer, maintained at -10°C.This method uses one dimensional Fourier equation applied to regular shapes. For this, the experimental temperature data obtained from cylindrical and spherical shaped products during pre-cooling was utilised. Such temperature and thermal diffusivity profiles can be readily used with other information such as degradation rate, etc. to evaluate thermal treatments based on cold air cooling methods for storage of perishable food products.

Keywords: thermal diffusivity, skin temperature, precooling, forced convection, regular shaped

Procedia PDF Downloads 460

Authors: Kshitish Ch. Mistri, Abhishek Kumar Singh

Abstract:

The effect of undulatory boundary surface of a medium as well as the degree of bonding between two consecutive mediums, on the propagation of surface waves is an unavoidable matter of fact. Therefore, this paper investigates the propagation of Rayleigh-type wave in a corrugated fibre-reinforced layer overlying an initially stressed orthotropic half-space under gravity. Also, the two mediums are assumed to be loosely (or imperfectly) bonded. Numerical computation of the obtained frequency equation has been carried out which aids to analyze the influence of corrugation, loose bonding, initial stress and gravity on the phase velocity of Rayleigh-type wave. Moreover, the presence and absence of corrugation, loose bonding and initial stress are also discussed in a comparative manner.

Keywords: corrugated boundary surface, fibre-reinforced layer, initial stress, loose bonding, orthotropic half-space, Rayleigh-type wave

Procedia PDF Downloads 276

Authors: Vipresh Mehta , Aman Abhishek, Jatin Batra, Gautam Iyer

Abstract:

Huge amount of solar radiation reaching the earth can be harnessed to provide electricity through Photo voltaic (PV) panels. The solar PV is an exciting technology but suffers from low efficiency. A study on low efficiency in multi MW solar power plants reveals that the electric yield of the PV modules is reduced due to reflection of the irradiation from the sun and when a module’s temperature is elevated, as there is decrease in the voltage and efficiency. We intend to alter the structure of the PV system, We also intend to improve the efficiency of the Solar Photo Voltaic Panels by active cooling to reduce the temperature losses considerably and decrease reflection losses to some extent. Reflectors/concentrators and anti-reflecting coatings are also used to intensify the amount of output produced from the system. Apart from this, transformer-less Grid-tied Inverter. And also, a T-LCL immitance circuit is used to reduce the harmonics and produce a constant output from the entire system.

Keywords: PV panels, efficiency improvement, active cooling, quantum dots, organic-inorganic hybrid 3D panel, ground water tunneling

Procedia PDF Downloads 773

Authors: Abhishek, Seema Devi, Jyoti Ohri

Abstract:

A mobile ad hoc network (MANET) represents a system of wireless mobile nodes that can self-organize freely and dynamically into arbitrary and temporary network topology. Unlike a wired network, wireless network interface has limited transmission range. Routing is the task of forwarding data packets from source to a given destination. Ad-hoc On Demand Distance Vector (AODV) routing protocol creates a path for a destination only when it required. This paper describes the implementation of AODV routing protocol using MATLAB-based Truetime simulator. In MANET's node movements are not fixed while they are random in nature. Hence intelligent techniques i.e. fuzzy and ANFIS are used to optimize the transmission range. In this paper, we compared the transmission range of AODV, fuzzy AODV and ANFIS AODV. For soft computing AODV, we have taken transmitted power and received threshold as input and transmission range as output. ANFIS gives better results as compared to fuzzy AODV.

Keywords: ANFIS, AODV, fuzzy, MANET, reactive routing protocol, routing protocol, truetime

Procedia PDF Downloads 499

Authors: Kushagra Khandelwal, Chinmay Anand, Sharmistha Banerjee

Abstract:

This paper presents an approach to news aggregation that is aimed at solving the issues centered on depolarization and manipulation of news information and stories. Largest democracies across the globe face numerous issues related to news democratization. With the advancements in technology and increasing outreach, web has become an important information source which is inclusive of news. Research was focused on the current millennial population consisting of modern day internet users. The study involved literature review, an online survey, an expert interview with a journalist and a focus group discussion with the user groups. The study was aimed at investigating problems associated with the current news system from both the consumer as well as distributor point of view. The research findings helped in producing five key potential opportunity areas which were explored for design intervention. Upon ideation, we identified five design features which include opinion aggregation. Categorized opinions, news tracking, online discussion and ability to take actions that support news democratization.

Keywords: citizen journalism, democratization, depolarized news, napsterization, news aggregation, opinions

Procedia PDF Downloads 222

Authors: Abhishek Kumar Chandra, Kaushal Kishor, Wasim Khan, Dhananjay Singh, M. S. Alam

Abstract:

Single phase fluid flow through series of uniform microchannels connected via transition section (converging-diverging section with or without throat) was analytically and numerically studied to characterize the flow within the channel and in the transition sections. Three sets of microchannels of diameters 100, 184, and 249 μm were considered for investigation. Each set contains 10 numbers of microchannels of length 20 mm, connected to each other in series via transition sections. Transition section consists of either converging-diverging section with throat or without throat. The effect of non-uniformity in microchannels on pressure drop was determined by passing water/air through the set of channels for Reynolds number 50 to 1000. Compressibility and rarefaction effects in transition sections were also tested analytically and numerically for air flow. The analytical and numerical results show that these configurations can be used in enhancement of transport processes. However, converging-diverging section without throat shows superior performance over with throat configuration.

Keywords: contraction-expansion flow, integrated microchannel, microchannel network, single phase flow

Procedia PDF Downloads 282

Authors: Abhishek Gandhi, Naresh Bhatnagar

Abstract:

In this article, a new technique has been developed to manufacture open cell extruded thermoplastic foamed sheets with the aid of extrudate surface-quenching phenomenon. As the extrudate foam exits the die, its surface is rapidly quenched which results in freezing of cells on the surface, while the cells at the core continue to grow and leads to development of open-cellular microstructure at the core. Influence of chill roll temperature was found to be extremely significant in developing porous morphological attributes. Subsequently, synergistic effect of blowing agent content and chill roll temperature was examined for their expansion ratio and open-cell microstructure. Further, chill roll rotating speed was found extremely significant in obtaining open-cellular foam structures. This study intends to enhance the understanding of researchers working in the area of open-cell foam processing.

Keywords: foams, porous materials, morphology, composite, microscopy, open-cell foams

Procedia PDF Downloads 448

Authors: Ayoti Banerjee, Meenakshi Banerjee

Abstract:

The study of metamorphic reaction textures is important in contributing to our understanding of the evolution of metamorphic terranes. Where preserved, they provide information on changes in the P-T conditions during the metamorphic history of the rock, and thus allow us to speculate on the P-T-t evolution of the terrane. Mafic dykes have attracted the attention of petrologists because they act as window to mantle. This rock represents a mafic dyke of doleritic composition. It is fine to medium grained in which clinopyroxene are enclosed by the lath shaped plagioclase grains to form spectacular ophitic texture. At places, sub ophitic texture was also observed. Grains of pyroxene and plagioclase show very less deformation typically plagioclase showing deformed lamella along with plagioclase-clinopyroxene-phyric granoblastic fabric within a groundmass of feldspar microphenocrysts and Fe–Ti oxides. Both normal and reverse zoning were noted in the plagioclase laths. The clinopyroxene grains contain exsolved phases such as orthopyroxene, plagioclase, magnetite, ilmenite along the cleavage traces and the orthopyroxene lamella form granules in the periphery of the clinopyroxene grains. Garnet corona also develops preferentially around plagioclase at the contact of clinopyroxene, ilmenite or magnetite. Tiny quartz and K-fs grains showed symplectic intergrowth with garnet at a few places. The product quartz formed along with garnet rims the coronal garnet and the reacting clinopyroxene. Thin amphibole corona formed along the periphery of deformed plagioclase and clinopyroxene occur as patches over the magmatic minerals. The amphibole coronas cannot be assigned to a late magmatic stage and are interpreted as reactive being restricted to the contact between clinopyroxene and plagioclase, thus postdating the crystallization of both. The amphibole and garnet do not share grain boundary in the entire rock and is thus pointing towards simultaneous crystallization. Olivine is absent. Spectacular myrmekitic growth of orthoclase and quartz rimming the plagioclase is consistent with the potash metasomatic effects that is also found in other rocks of this region. These textural features are consistent with a phase of fluid induced metamorphism (retrogression). But the appearance of coronal garnet and amphibole exclusive of each other reflects the participation if Ti as the prime reason. Presence of Ti as a reactant phase is a must for amphibole forming reactions whereas it is not so in case of garnet forming reactions although the reactants are the same plagioclase and clinopyroxene in both cases. These findings are well validated by petrographical and textural analysis. In order to obtain balanced chemical reactions that explain formation of amphibole and garnet in the mafic dyke rocks a matrix operation technique called Singular Value Decomposition (SVD) was adopted utilizing the measured chemical compositions of the minerals. The computer program C-Space was used for this purpose and the required compositional matrix. Data fed to C-Space was after doing cation-calculation of the oxide percentages obtained from EPMA analysis. The Garnet-Clinopyroxene geothermometer yielded a temperature of 650 degrees Celsius. The Garnet-Clinopyroxene-Plagioclase geobarometer and Al-in amphibole yielded roughly 7.5 kbar pressure.

Keywords: corona, dolerite, geothermometer, metasomatism, metamorphic reaction texture, retrogression

Procedia PDF Downloads 280

Authors: Muskaan Sethi, Arnab Banerjee, Bappaditya Manna

Abstract:

The present paper aims to investigate a suitable contact between a wheel rolling over a flexible beam. A Linear Complementary (LCP) based approach has been adopted to simulate the contact dynamics for a rigid wheel traversing over a flexible Euler Bernoulli simply supported beam. The adopted methodology is suitable to incorporate the effect of frictional force acting at the wheel-beam interface. Moreover, the possibility of the generation of a gap between the two bodies has also been considered. The present method is based on a unilateral contact assumption which assumes that no penetration would occur when the two bodies come in contact. This assumption helps to predict the contact between wheels and beams in a more practical sense. The proposed methodology is validated with the previously published results and is found to be in good agreement. Further, this method is applied to simulate the contact between wheels and beams for various railway configurations. Moreover, different parametric studies are conducted to study the contact dynamics between the wheel and beam more thoroughly.

Keywords: contact dynamics, linear complementary problem, railway dynamics, unilateral contact

Procedia PDF Downloads 102

Authors: Abhishek Ranga

Abstract:

The study examined the effect of accounting choice and level of disclosure on the firm’s implied cost of equity in Indian environment. For the study accounting choice was classified as aggressive or conservative depending upon the firm’s choice of accounting methods, accounting policies and accounting estimates. Level of disclosure is the quantum of financial and non-financial information disclosed in firm’s annual report, essentially in note to accounts section, schedules forming part of financial statements and Management Discussion and Analysis report. Regression models were developed with cost of equity as a dependent variable and accounting choice, level of disclosure as an independent variable along with selected control variables. Cost of equity was measured using Edward-Bell-Ohlson (EBO) valuation model, to measure accounting choice Modified-Jones-Model (MJM) was used and level of disclosure was measured using a disclosure index essentially drawn from Botosan study. Results indicated a negative association between the implied cost of equity and conservative accounting choice and also between level of disclosure and cost of equity.

Keywords: aggressive accounting choice, conservative accounting choice, disclosure, implied cost of equity

Procedia PDF Downloads 462