526 research outputs found

    Communications for smart grid substation monitoring using WIMAX protocol

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    The SMARTGRID is a general term for a series of infrastructural changes applied to the electric transmission and distribution systems. By using the latest communication and computing technology, additional options such as Condition Monitoring can now be implemented to further improve and optimise complex electricity supply grid operation. Lifecycle optimisation of high voltage assets and other system components in the utility provide a case in point. Today Utility experts agree that application of scheduled maintenance is not the effective use of resources. To reduce maintenance expenses and unnecessary outages and repairs of equipment due to scheduled maintenance, utilities are adopting condition based approaches. Real time online monitoring of substation parameters can be achieved by retrofitting the existing substation with SMARTGRID technology. The IEC 61850 is a common protocol meant for Substation Automation Systems, designed for the purpose of establishing interoperability, one that all manufacturers of all different assets must comply with. This thesis advocates the estimation of bandwidth required for monitoring a substation after retrofitting the existing substation with smart communication technologies. This includes establishing a latest wireless communication infrastructure from the substation to the control centre and evaluating the performance modelling and simulating the physical layer of communication technologies such as WIMAX (IEEE802.16) and MICROWAVE point to point using MATLAB SIMULINK and RADIO mobile online simulation software. Also, link budget of the satellite communication for the same application is calculated. Satellite communication in this case is considered as a redundant or back up technology to ensure that the communication between entities is continuous. On performing the simulation on different environments the results prove that the selected protocols are best suited for condition monitoring. The measured Latency could be the best approximated value which complies with the current objective. However the white noise that exists in the substation has significant hazard with respect to the security of the wireless network. To compensate this constraint whole substation is hard wired by means of plastic fibre optics and the data sent to the base station located near the substation

    Studies of phosphorus metabolism of Hordeum vulgare L. plants infected with bromegrass mosaic virus

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    Call number: LD2668 .T4 1966 R161Master of Scienc

    Modeling of Breakdown Voltage of White Minilex Paper in the Presence of Voids Using Fuzzy Logic

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    Occluded gaseous cavities within the insulating materials are potential sources of electrical trees which can lead to continuous deterioration and breakdown of materials. To determine the suitability of use and to acquire the data for the dimensioning of electrical insulation systems breakdown voltage of insulators should be determined. In this project, Fuzzy Logic (FL) method is used to model breakdown voltages of White Minilex Paper samples based on experimental data generated in the laboratory. Two models are proposed with triangular and trapezoidal shape of the membership functions for the FL under both dc and ac voltage conditions. The cavities are created artificially with different dimensions. Low values of mean absolute errors of the estimated breakdown voltage of the test data show the effectiveness of such models

    Auto profile

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    Master of ScienceDepartment of Computing and Information SciencesDaniel A. AndresenPresent times most of the applications allow users to set profiles and activate them manually. Also, there is no such application to alert the calling person automatically whenever we are busy in a meeting. Auto Profile is an application which addresses these issues. Using this application, a custom profile can be created and activated. The user of this application can create any number of custom profiles with their own timings depending on their requirements from the available set of ringer modes such as vibration, silent, normal modes. All these settings will be changed automatically when they define a profile and set it as active. Every profile can be scheduled according to their wish. Also, users can define how often and how long they would like to activate the selected profile. Auto Profile Switcher will recognize their profile based on the current time and it will apply the right profile at the right time according to the given settings. For instance, they can save a home profile and a work profile, and the application will automatically switch from one to other automatically, without any user action. It's also possible for the users to apply manually saved profile wherever they are. Also, the application allows users not to bother about the calls from important persons when they are in some important meeting or busy. Automatically profile is activated as scheduled and sends a respective alert to the caller according to the profile activated. Auto Profile application is user-friendly and easy to use. The proposed application is developed for the android platform, which is used to create custom profiles and make sure that the tasks are executed as scheduled. This relieves users as they do not need to bother about the calls when they are in some important meeting or busy. As this is a mobile application users can easily organize their action wherever they are with ease

    Studies On 3/7 Caspase Activity And Apoptosis Induction By Diarylheptaniods Isolated From Garuga Pinnata Roxb

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    This study aims to evaluate the stimulation of caspase 3/7, 8 and 9 activity and induction of apoptosis by the diarylheptanoids isolated from Garuga pinnata (G. pinnata) RoxB. Garuganin 1, 3, 4 and 5 which were previously reported for their isolation have tested for their anticancer potencies by different caspase activation and apoptosis induction in MCF-7 and HCT-15 cell lines. However, based on the MTT assay results (Previously reported) Garuganin 3 and 5 were selected for this study.  from the stem bark of G. pinnata. The activation of caspases 3/7, 8, and 9 is a conformational process of cancer cell death. Such activation of caspases by different concentrations (05, 10, 15, 2

    An event-driven probabilistic model of sound source localization using cochlea spikes

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    This work presents a probabilistic model that estimates the location of sound sources using the output spikes of a silicon cochlea such as the Dynamic Audio Sensor. Unlike previous work which estimated the source locations directly from the interaural time differences (ITDs) extracted from the timing of the cochlea spikes, the spikes are used instead to support a distribution model of the ITDs representing possible locations of sound sources. Results on noisy single speaker recordings show average accuracies of approximately 80% on detecting the correct source locations and an estimation lag of <;100ms

    Prediction of Broadband Noise from Symmetric and Cambered Airfoils

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    Aerodynamic sound generation and self-noise mechanisms from lifting surfaces such as airfoil involve the fields of classical acoustics and fluid mechanics. In this paper, trailing edge noise production is evaluated using empirical model for NACA 0012 and NACA 6320 airfoils. The sound pressure levels from trailing edge surface are calculated for different flow configurations. The growth of boundary layer thickness and displacement thickness, for different chord lengths and Mach numbers with varying angles of attack, is illustrated for NACA 0012. The sound pressure levels were computed numerically between 00 to 60 angles of attack and at constant chord length of 1.2m using Brookes Pope Marcolini method. The results showed a change of ~2-5dB in peak amplitude for mid frequencies region of spectrum. The effects of varying chord length and Mach number on sound pressure levels are illustrated for both airfoils. The relative velocity field for airfoils was computed using the boundary element method. The combined effect of thickness and camber on sound power level is demonstrated at a 40 angle of attack and for a Mach number of 0.191. Validation of sound pressure levels is done based on the results obtained for NACA0012 for similar flow conditions
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