38 research outputs found
Sangrahaka: A Tool for Annotating and Querying Knowledge Graphs
In this work, we present a web-based annotation and querying tool Sangrahaka.
It annotates entities and relationships from text corpora and constructs a
knowledge graph (KG). The KG is queried using templatized natural language
queries. The application is language and corpus agnostic, but can be tuned for
special needs of a specific language or a corpus. A customized version of the
framework has been used in two annotation tasks. The application is available
for download and installation. Besides having a user-friendly interface, it is
fast, supports customization, and is fault tolerant on both client and server
side. The code is available at https://github.com/hrishikeshrt/sangrahaka and
the presentation with a demo is available at https://youtu.be/nw9GFLVZMMo
Interactive three-dimensional boundary element stress analysis of components in aircraft structures
Graphically Driven Interactive Stress Reanalysis for Machine Elements in the Early Design Stage
In this work a new graphically driven interactive stress reanalysis finite element technique has been developed so that an engineer can easily carry out manual geometric changes in a machine element during the early design stage. The interface allow an engineer to model a machine element in the commercial finite element code ANSYS® and then modify part geometry graphically to see instantaneous graphical changes in the stress and displacement contour plots. A reanalysis technique is used to enhance the computational performance for solving the modified problem; with the aim of obtaining results of acceptable accuracy in as short a period of time in order to emphasize the interactive nature of the design process.
Three case studies are considered to demonstrate the effectiveness of the prototype graphically driven reanalysis finite element technique. The finite element type considered is a plane stress four-node quadrilateral based on a homogenous, isotropic, linear elastic material. The first two problems consider a plate with hole and plate with fillets. These two examples demonstrate that by changing the hole and fillet size/shape, an engineer can manually obtain an optimum design based on the stress concentration factor, i.e. engineer-driven optimization process. Each case study considered multiple redesigns. A combined approximation reanalysis method is used to solve each redesigned problem. The third case study considers a support bracket. The goal is to design the cantilever portion of the bracket to have uniform strength and to minimize the stress concentration at the fillet.
The major beneficiaries of the work will be engineers working in product development and validation of components and structures, which are subjected to mechanical loads. The scientific and technological relevance of this work applies not only to the early stage of design, but to a number of other applications areas in which benefits may accrue. A company may have needs for a rapid analysis and re-analysis tool for fatigue assessment of components manufactured slightly out of tolerance. Typically this needs to be carried out under a very restrictive time scale
Detection and Prevention of Sybil Attacks on Non- Stationary Nodes without Trusted Authority
—In a common remote sensor orchestrate, the batteries of the hubs near the sink deplete snappier than various centers in view of the data action concentrating towards the sink, abandoning it stranded and disturbing the sensor data reporting. To soothe this issue, versatile sinks are proposed. They positively give stack balanced data conveyance and accomplish uniform-vitality usage over the framework. On the other hand, publicizing the position of the adaptable sink to the framework introduces an overhead with respect to imperativeness use and package delays. In this paper, we propose Ring Routing, a novel, conveyed, vitality proficient portable sink steering convention, reasonable for time-delicate applications, which hopes to minimize this overhead while ensuring the advantages of versatile sinks. Furthermore, we assess the execution of Ring Routing by method for wide amusements. Each node sharing RSSI values to vet each othe
Direct Numerical Simulation of Swirling Flows using the Front Tracking Method
Swirling multiphase flows are found in a wide range of industrial processes. Such flows are used for separation of flows containing phases of different densities and for devices such as the spinning tensiometer. These flows are challenging to predict computationally, due to the presence of a phase boundary and the large pressure gradient generated by the swirl. In the present work the applicability of the front tracking method to swirling multi-phase flows is demonstrated by studying the evolution of a bubble in spinning tensiometer. Previous studies show that the evolution of a bubble in the spinning drop tensiometer can be used to measure the interfacial tension and other rheological properties. The front tracking method is applied to the spinning tensiometer problem to study several cases and verify the convergence of the solutions. The results are validated with other computational methods, theoretical models and experimental results. The length scales obtained from the front tracking method are in agreement with the corresponding values from experiments and other computational studies. The shape of the end of the elongated bubble obtained from the simulations is found to be similar to that suggested by a theoretical expression from previous studies. The simulations predict that the relaxation of bubble radius is exponential with time, at a rate that is found to be slightly greater than that predicted by the theoretical model
Unique Challenges in the Design and Operation Philosophy of Solar Thermal Power Plants
AbstractSolar thermal power plant design and operation philosophy involves unique challenges as compared to design of conventional thermal power plants. The solar receiver operation should be able to absorb maximum solar load during transient events like daily start-up and shut-down. This requires aggressive ramp rates for transient operation of the power plant. However, the component and system level limitations must be considered in formulating these modes of operation and ramp rates.A solar receiver which usually receives heat from heliostats is designed to receive high heat flux to operate at high temperature and pressure during daytime. However, during night-time the receiver receives no heat flux and is losing heat to the environment. Day-night cyclic operation of a solar thermal power plant induces thermal cycles in the solar receiver pressure parts. Since solar receiver tubes are not insulated, the amplitude of thermal cycling is significant and needs to be addressed with proper tools and design approach. Besides, higher plant cycle efficiency requires higher operating temperature and pressure of a solar receiver, further increasing the amplitude of thermal cycling. The system level and component level response to these day-night cycles has a significant impact on modes of operation as well as on the life usage of various components. It also affects the design, specifications and operation of various plant level components.The solar thermal power plant design and operation process is optimized by having a system level thermal-hydraulics model for the solar receiver to simulate the transient start-up and shut-down events. Since all of the major components of the system are included in the model, it reflects the transient response of each of the components on each other and on the overall system. This simulation can be used to generate input conditions for component level life usage analysis. The component level life usage analysis is done using the finite-element method. The component level life usage analysis determines the permissible ramp rates. The thermal-hydraulics dynamic simulation outlines the operational philosophy of the system
APPROVED: Graphically Driven Interactive Stress Reanalysis for Machine Elements in the Early Design
In this work a new graphically driven interactive stress reanalysis finite element technique has been developed so that an engineer can easily carry out manual geometric changes in a machine element during the early design stage. The interface allow an engineer to model a machine element in the commercial finite element code ANSYS ® and then modify part geometry graphically to see instantaneous graphical changes in the stress and displacement contour plots. A reanalysis technique is used to enhance the computational performance for solving the modified problem; with the aim of obtaining results of acceptable accuracy in as short a period of time in order to emphasize the interactive nature of the design process. Three case studies are considered to demonstrate the effectiveness of the prototype graphically driven reanalysis finite element technique. The finite element type considered is a plane stress four-node quadrilateral based on a homogenous, isotropic, linear elastic material. The first two problems consider a plate with hole and plate with fillets. These two examples demonstrate that by changing the hole and fillet size/shape
Design and Development of Patch Textile-Antenna
The recent advancements show that wireless devices can be developed in a compact form. This miniaturization has led to the demand of an antenna for communication which is small itself and doesn’t compromise on its performance characteristics. An antenna that actually forms a part of clothing without affecting the wearer’s health can prove to be of very useful for Body Area Network (BAN) applications. This suggests the development of an antenna design in microstrip patch form with some specific fabric used as a substrate and who are conducting parts will comprise of conductive material like copper. The antenna can be developed in the ISM band frequency spectrum. Such an antenna can be fabricated in a number of forms using copper tape, conductive fabric or ink. The novelty of the proposed antenna is simple planar configuration, ease in fabrication and very economical. A fabric with suitable dielectric constant and thickness can contribute as a substrate such as pure cotton. Parameters like return loss, and voltage surface wave ratio are used for performance measurement of the design. SAR measurement is also done to ensure that the antenna is safe to be used around human bod