236 research outputs found
Studies of Histidine, Phenylalanine Complexes of Oxovanadium(IV) Derived from Acetylacetone
Get PDFSchiff base complexes of oxovanadium(IV) with amino acids and acetylacetone were synthesized and characterized by elemental analysis, conductivity measurements, spectral and magnetic data. The complexes were found to be non-electrolytes and stoichiometry shown 1:1. The spectral and magnetic data were suggesting the square pyramidal geometr
Thermal Network Calibration Using Short-Transient and Steady-State Thermal Tests
No full textThis paper describes the process of calibration of a full-scale steady-state thermal network of a 4 kW induction motor. The pre cursor to this calibration process is the winding thermal test of the motor; where the series connected three phase winding is supplied with de voltage. A short-transient test as well as a steady-state test have been performed. The main heat-flow path is from winding to the stator core then onto to the motor housing. By adjusting the thermal parameters along this path, a good agreement between the temperatures predicted by the analytical thermal circuit and the measured winding and frame temperatures can be found. This process of calibration allows reliable estimation of effective winding thermal conductivity, and contact resistances in the stator side of the motor, which are usually difficult to determine solely through analytical means
Inverse Thermal Analysis of Electrical Machines
No full textThis thesis focuses on the inverse thermal process of determining power losses of electrical machines from temperature measurements. The feasibility of this endeavour is investigated and the inverse mapping of losses with analytical and numerical thermal models of a 37 kW cage induction motor are demonstrated. Accurate lumped thermal networks as well as 2D and 3D finite element models of a 37 kW motor are built as forward thermal models for this purpose. Attention is given to managing error in measurement so that the temperature-to-source mapping can be accurate. The inverse mapping was achieved with two methods - least squares and conjugate gradient.
The results of the inverse mapping indicate that inverse thermal approaches hold promise in estimating losses in machine domains where direct measurements are cumbersome, such as the stator yoke or tooth regions. Lumped and distributed loss components could be recovered reliably using both inverse methods. Furthermore, a water-cooled calorimeter was designed and built to measure the total power loss of the induction motor. With only a few measured temperatures of the motor, the inverse thermal process is able to segregate the total losses into its constituent components
Electrical Machines Second Order Thermal Model a Viable Solution for Electric Drives
No full textThis paper describes from the analytical and practical point of view a second order thermal model useful for predicting the electrical machine winding average temperature used in electrical drives. Even if the model has been used and calibrated on an induction motor, the presented model has a general validity and can be adopted for all the electrical machines
Data privacy in knowledge discovery
No full textThis thesis addresses data privacy in various stages of extracting knowledge embedded in databases. Advances in computer networking and database technologies have enabled the collection and storage of vast quantities of data. Legal and ethical considerations might require measures to protect an individual's privacy in any use or release of the data. In this thesis, we address the problem of preserving privacy in the two following cases: (1) in distributed knowledge discovery; (2) in situations where the output of a data mining algorithm could itself breach privacy. We present results in two different models, namely secure multiparty computation (SMC) and differential privacy. The first part of the thesis presents privacy preserving protocols in the SMC model. Secure multiparty computation involves the collaborative computation of functions based on inputs from multiple parties. The privacy goal is to ensure that all parties receive only the final output without any party learning anything beyond what can be inferred from the output. Within this framework we address the problem of preserving privacy in the preprocessing and the data mining stages of knowledge discovery in databases. For the preprocessing stage, we present private protocols for the imputation of missing data in a dataset that is shared between two parties. For the data mining stage, we introduce the notion of arbitrarily partitioned data that generalizes both horizontally and vertically partitioned data. We present a privacy-preserving protocol for k-means clustering of arbitrarily partitioned data. We also develop a new simple k-clustering algorithm that was designed to be converted into a communication-efficient protocol for private clustering. The second part of the thesis deals with privacy in situations where the output of a data mining algorithm could itself breach privacy. In this setting, we present private inference control protocols in the SMC model for On-line Analytical Processing systems. In the differential privacymodel, the goal is to provide access to a statistical database while preserving the privacy of every individual in the database, irrespective of any auxiliary information that may be available to the database client. Under this privacy model, we present a practical privacy preserving decision tree classifier using random decision trees.Ph.D.Includes abstractVitaIncludes bibliographical referencesby Geetha Jagannatha
A dangerous but powerful idea - counter acceleration and speed with slowness and wholeness
No full textThe dangerous idea is that school reform, in India in particular, but across the world too, is impossible. Changing education, at the systemic level or at the institutional or school level, or educating teachers and school leaders in change can be classified as largely first order change - that of school improvement, which involves doing more of the same but doing it better (where the focus is on efficiency) and that of school re-structuring, which involves re-organising components and responsibilities (where the focus is on effectiveness). Geetha Narayanan is Principal Investigator with Project Vision at the Centre for Education Research Training and Development (CERTAD) within the Srishti School of Art Design and Technology in Bangalore, India. She has dedicated her career to finding and establishing new models of education that are creative, synergistic and original in their approach to learning. Read the article and listen to audio of the author discussing her ideas
Tetranchyroderma hystrix Remane 1926
No full textTetranchyroderma hystrix Remane, 1926 Records from India. KERALA: Neendakara—Rajan & Nair (1979). Habitat. It has been recorded in well sorted sand with grain size ranging mostly from 295 to 592 µm Remarks. This species has been recorded by Rajan & Nair (1979) from Kerala in their ecological work, along with other gastrotrichs species and meiofauna. There is no drawing and other taxonomic data of this species provided by them or any other author from India. Consequently, we consider this species finding as a doubtful record that require more evidence to prove the presence of this species on the Indian coast.Published as part of Chatterjee, Tapas, Priyalakshmi, Geetha & Todaro, M. Antonio, 2019, An annotated checklist of the macrodasyidan Gastrotricha from India, pp. 495-510 in Zootaxa 4545 (4) on page 503, DOI: 10.11646/zootaxa.4545.4.3, http://zenodo.org/record/261830
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