Load flow solution for meshed distribution networks

Power flow is a useful tool in operation, planning and optimisation of a system. Distribution systems, generally, refers to the power system network connected to loads at lower operating voltage. In this thesis an efficient power flow method for solving meshed distribution networks by using current injection method and basic formulations of Kirchhoff's laws has been acknowledged. This method has excellent convergence characteristics and thus is more efficient than Newton-Raphson and Fast Decoupled Method. This method can be applied to the solution of both the three-phase (unbalanced) and single-phase (balanced) representation of the network. The main objective of this thesis is to study the Forward-Backward Sweep and to derive the inference that how much efficient it is in solving the load flow problem of the meshed distribution networks

Material model calibration through indentation test and stochastic inverse analysis

Eksperiment instrumentalnog utiskivanja se sve više koristi za karakterizaciju materijala različitog tipa. Razvijene metode kombinuju ovaj test sa kompjuterskom simulacijom u okviru inverznih analiza sa ciljem dobijanja parametara koji ulaze u jednačine različitih konstitutivnih modela. Izlaz iz ovakvih procedura predstavljaju vrednosti traženih parametara u determinističkom smislu, dok je za praktičnu inženjersku upotrebu poželjno raspolagati i sa procenom tačnosti dobijenih vrednosti. U ovom radu prikazana je numeričko-eksperimentalna metoda zasnovana na inverznoj analizi koja kao ulazni podatak koristi eksperimentalno izmerenu krivu utiskivanja (kriva koja daje zavisnost primenjene sila u funkciji ostvarene dubine utiskivanja). Numeričke simulacije testa utiskivanja su značajno ubrzame primenom redukovanog modela zasnovanog na pravilnoj ortogonalnoj dekompoziciji a posebno razvijenom za ovu svrhu. Rezultijući inverzni problem je rešen u stohastičkom kontekstu korišćenjem Monte Karlo simulacija kao i Kalmanovih filtera. Dobijeni rezultati su komparativno prezentovani u cilju poređenja dobijene tačnosti i računarske efikasnosti.Indentation test is used with growing popularity for the characterization of various materials on different scales. Developed methods are combining the test with computer simulation and inverse analyses to assess material parameters entering into constitutive models. The outputs of such procedures are expressed as evaluation of sought parameters in deterministic sense, while for engineering practice it is desirable to assess also the uncertainty which affects the final estimates resulting from various sources of errors within the identification procedure. In this paper an experimental-numerical method is presented centered on inverse analysis build upon data collected from the indentation test in the form of force-penetration relationship (so-called 'indentation curve'). Recursive simulations are made computationally economical by an 'a priori' model reduction procedure. Resulting inverse problem is solved in a stochastic context using Monte Carlo simulations and non-sequential Extended Kalman filter. Obtained results are presented comparatively as for accuracy and computational efficiency

Reduced Order Numerical Modeling for Calibration of Complex Constitutive Models in Powder Pressing Simulations

Numerical simulations of different ceramic production phases often involve complex constitutive models, with difficult calibration process, relying on a large number of experiments. Methodological developments, proposed in present paper regarding this calibration problem can be outlined as follows: assessment of constitutive parameters is performed through inverse analysis procedure, centered on minimization of discrepancy function which quantifies the difference between measurable quantities and their computed counterpart. Resulting minimization problem is solved through genetic algorithms, while the computational burden is made consistent with constraints of routine industrial applications by exploiting Reduced Order Model (ROM) based on proper orthogonal decomposition. Throughout minimization, a gradual enrichment of designed ROM is used, by including additional simulations. Such strategy turned out to be beneficial when applied to models with a large number of parameters. Developed procedure seems to be effective when dealing with complex constitutive models, that can give rise to non-continuous discrepancy function due to the numerical instabilities. Proposed approach is tested and experimentally validated on the calibration of modified Drucker-Prager CAP model, frequently adopted for ceramic powder pressing simulations. Assessed values are compared with those obtained by traditional, time-consuming tests, performed on pressed green bodies

Exploiting Kerr Cross Non-linearity in Circuit Quantum Electrodynamics for Non-demolition Measurements

We propose a scheme for dispersive readout of stored energy in one mode of a nonlinear superconducting microwave ring resonator by detection of the frequency shift of a second mode coupled to the first via a Kerr nonlinearity. Symmetry is used to enhance the device responsivity while minimizing self nonlinearity of each mode. Assessment of the signal to noise ratio indicates that the scheme will function at the single photon level, allowing quantum non-demolition measurement of the photon number state of one mode. Experimental data from a simplified version of the device demonstrating the principle of operation are presented.Comment: 12 pages, 4 figure

Millimeter-Wave Lumped Element Superconducting Bandpass Filters for Multi-Color Imaging

The opacity due to water vapor in the Earth's atmosphere obscures portions of the sub-THz spectrum (mm/sub-mm wavelengths) to ground based astronomical observation. For maximum sensitivity, instruments operating at these wavelengths must be designed to have spectral responses that match the available windows in the atmospheric transmission that occur in between the strong water absorption lines. Traditionally, the spectral response of mm/sub-mm instruments has been set using optical, metal-mesh bandpass filters [1]. An alternative method for defining the passbands, available when using superconducting detectors coupled with planar antennas, is to use on-chip, superconducting filters [2]. This paper presents the design and testing of superconducting, lumped element, on-chip bandpass filters (BPFs), placed inline with the microstrip connecting the antenna and the detector, covering the frequency range from 209–416 GHz. Four filters were designed with pass bands 209–274 GHz, 265–315 GHz, 335–361 GHz and 397–416 GHz corresponding to the atmospheric transmission windows. Fourier transform spectroscopy was used to verify that the spectral response of the BPFs is well predicted by the computer simulations. Two-color operation of the pixels was demonstrated by connecting two detectors to a single broadband antenna through two BPFs. Scalability of the design to multiple (four) colors is discussed

Reduced Order Numerical Modeling for Calibration of Complex Constitutive Models in Powder Pressing Simulations

Numerical simulations of different ceramic production phases often involve complex constitutive models, with difficult calibration process, relying on a large number of experiments. Methodological developments, proposed in present paper regarding this calibration problem can be outlined as follows: assessment of constitutive parameters is performed through inverse analysis procedure, centered on minimization of discrepancy function which quantifies the difference between measurable quantities and their computed counterpart. Resulting minimization problem is solved through genetic algorithms, while the computational burden is made consistent with constraints of routine industrial applications by exploiting Reduced Order Model (ROM) based on proper orthogonal decomposition. Throughout minimization, a gradual enrichment of designed ROM is used, by including additional simulations. Such strategy turned out to be beneficial when applied to models with a large number of parameters. Developed procedure seems to be effective when dealing with complex constitutive models, that can give rise to non-continuous discrepancy function due to the numerical instabilities. Proposed approach is tested and experimentally validated on the calibration of modified Drucker-Prager CAP model, frequently adopted for ceramic powder pressing simulations. Assessed values are compared with those obtained by traditional, time-consuming tests, performed on pressed green bodies

Superconducting resonators as beam splitters for linear-optics quantum computation

A functioning quantum computer will be a machine that builds up, in a programmable way, nonclassical correlations in a multipartite quantum system. Linear optics quantum computation (LOQC) is an approach for achieving this function that requires only simple, reliable linear optical elements, namely beam splitters and phase shifters. Nonlinear optics is only required in the form of single-photon sources for state initialization, and detectors. However, the latter remain difficult to achieve with high fidelity. A new setting for quantum optics has arisen in circuit quantum electrodynamics (cQED) using superconducting (SC) quantum devices, and opening up the way to LOQC using microwave, rather than visible photons. Much progress is being made in SC qubits and cQED: high-fidelity Fock state generation and qubit measurements provide single photon sources and detection. Here we show that the LOQC toolkit in cQED can be completed with high-fidelity (>99.92%) linear optical elements.Comment: 4 pages, 3 figure

A Comparative analysis of Intersectionality under Discrimination Law in the Light of Vulnerability Theory as a Post-Identity Approach

In spite of the presence of intersectionality as a concept in feminist literature for over twenty-five years, the State Policy, across the world, has been ignorant towards the interplay of identities and its role in the discrimination law jurisprudence. This article claims that a legitimate accommodation of a multi-ground claim under the Right to Equality regime, present in various legal systems, shall be a purposive step towards substantive equality. The article also highlights certain frailties associated with Intersectionality and introduces the age-old dilemma surrounding the formulation of State Policy, as to whether it should be ―identity-neutral‖ like anti-classification principle, or ―identity-sensitive‖ like intersectionality itself. The article also introduces the vulnerability theory proposed by Martha Fineman, as a post identity approach. The final analysis, explains how the two theories can coexist so that the State Policy can move towards substantive equality, and thus, mitigate the horrors of discrimination