Дисертації: "Generation of cryptographic parameters"

1

Wozny, Peter. "Elliptic curve cryptography: generation and validation of domain parameters in binary Galois Fields /." Online version of thesis, 2008. http://hdl.handle.net/1850/9695.

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2

Cai, Zhi, and 蔡植. "A study on parameters generation of elliptic curve cryptosystem over finite fields." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31225639.

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3

Traore, Mohamed. "Analyse des biais de RNG pour les mécanismes cryptographiques et applications industrielles." Thesis, Université Grenoble Alpes, 2022. http://www.theses.fr/2022GRALM013.

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Dans ce travail, nous analysons des certificats SSL/TLS X.509 (utilisant le chiffrement RSA et provenant de centaines de millions de matériels connectés) à la recherche d'anomalies et étendons notamment les travaux de Hastings, Fried et Heninger (2016). Notre étude a été réalisée sur trois bases de données provenant de l'EFF (2010-2011), de l'ANSSI (2011-2017) et de Rapid7 (2017-2021). Plusieurs vulnérabilités affectant des matériels de fabricants connus furent détectées : modules de petites tailles (strictement inférieures à 1024 bits), modules redondants (utilisés par plusieurs entités), certificats invalides mais toujours en usage, modules vulnérables à l'attaque ROCA ainsi que des modules dits «PGCD-vulnérables» (c'est-à-dire des modules ayant des facteurs communs). Pour la base de données de Rapid7, dénombrant près de 600 millions de certificats (et incluant ceux des matériels récents), nous avons identifié 1,550,382 certificats dont les modules sont PGCD-vulnérables, soit 0.27% du nombre total. Cela a permis de factoriser 14,765 modules de 2048 bits ce qui, à notre connaissance, n'a jamais été fait.En analysant certains modules PGCD-vulnérables, on a pu rétro-concevoir de façon partielle le générateur de modules (de 512 bits) utilisé par certaines familles de pare-feux, ce qui a permis la factorisation instantanée de 42 modules de 512 bits, correspondant aux certificats provenant de 8,817 adresses IPv4.Après avoir constaté que la plupart des modules factorisés avaient été générés par la bibliothèque OpenSSL, on a analysé les codes sources et les méthodes en charge du processus de génération de clefs RSA de plusieurs versions de cette bibliothèque (couvrant la période 2005 à 2021). À travers des expérimentations sur des plateformes à base de processeurs ARM, où l'on s'est mis quasiment dans les mêmes conditions que les matériels vulnérables identifiés, on a réussi à remonter aux causes de la PGCD-vulnérabilité
In this work, we analyze X.509 SSL/TLS certificates (using RSA encryption and from hundreds of millions of connected devices) looking for anomalies and notably extend the work of Hastings, Fried and Heninger (2016). Our study was carried out on three databases from EFF (2010-2011), ANSSI (2011-2017) and Rapid7 (2017-2021). Several vulnerabilities affecting devices from well-known manufacturers were detected: small moduli (strictly less than 1024 bits), redundant moduli (used by several entities), invalid certificates but still in use, moduli vulnerable to the ROCA attack as well as so-called “GCD-vulnerable” moduli (i.e. moduli having common factors). For the Rapid7 database, counting nearly 600 million certificates (and including those for recent devices), we have identified 1,550,382 certificates whose moduli are GCD-vulnerable, that is 0.27% of the total number. This made it possible to factor 14,765 moduli of 2048 bits which, to our knowledge, has never been done.By analyzing certain GCD-vulnerable moduli, we were able to partially reverse-engineer the modulus generator (of 512 bits) used by certain families of firewalls, which allowed the instantaneous factorization of 42 moduli of 512 bits, corresponding certificates from 8,817 IPv4 addresses.After noting that most of the factored moduli had been generated by the OpenSSL library, we analyzed the source codes and the methods in charge of the RSA key generation process of several versions of this library (covering the period 2005 to 2021). Through experiments on platforms based on ARM processors, where we put ourselves in almost the same conditions as the vulnerable devices identified, we managed to trace the causes of the PGCD-vulnerability

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4

Park, DongGook. "Cryptographic protocols for third generation mobile communication systems." Thesis, Queensland University of Technology, 2001.

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5

Guendouze, Cheikh. "Computer assisted generation of parameters for resistance spot welding." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319943.

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6

Paiva, Daniel S. "Using stylistic parameters to control a natural language generation system." Thesis, University of Brighton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418576.

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7

Brugnera, Leonardo. "Control of high harmonic generation by manipulation of field parameters." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9151.

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?High harmonic generation is a well established technique to investigate the structure and the inner dynamics of atoms and molecules. This thesis describes how the generating field parameters can be manipulated to extend the limits imposed on the technique by the use of traditional laser sources. In this field, with traditional source we mean high intensity, linearly polarised laser pulses at 800 nm. The first parameter to be investigated is the wavelength λ of the generating beam. The unfavourable scaling of the high harmonic yield with λ seems to suggest that high harmonic spectroscopy of atoms and molecules should be restricted to the wavelengths that obviate this problem, and that therefore shorter wavelength should be used. But longer wavelengths, in the mid infrared, present a great advantage respect to shorter ones. The maximum harmonic order that we can obtain is proportional to the ionisation potential of the target and to the wavelength times the intensity of the beam, so a higher number of harmonic can be produced with a longer wavelength than with short, the intensity being equal. This becomes incredibly valuable when the specie under investigation is a molecule with low ionisation potential. To produce high harmonics, a linearly polarised beam is required. If ellipticity is introduced in the beam, the harmonic signal quickly fades out, as non-linearly polarisation in monochromatic beams switches off the mechanism at the basis of high harmonic generation. This is not true if the polarisation of the beam is changed through the introduction of an additional laser beam, perpendicularly polarised respect to the fundamental. In this thesis the additional degree of freedom that this second field implies is investigated by combining the fundamental with its second harmonic and by controlling the relative delay of the two with sub-cycle precision. The key result is that the addition of the second harmonic gives access to the control of the harmonic amplitude and to the time at which the high harmonics are emitted, by simply controlling the relative phase between the two pulses.

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8

Lindblom, Markus. "Semi-Automatic Generation of Control Law Parameters for Generic Fighter Aircraft." Thesis, Linköpings universitet, Reglerteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-167725.

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Control law design can be an iterative and time-consuming process. The design procedure can often include manual tuning, not uncommonly in the form of trial and error. Modern software tools may alleviate this process but are generally not developed for use within any speciﬁc industry. There is therefore an apparent need to develop ﬁeld-speciﬁc tools to facilitate control law design.The main contribution of this thesis is the investigation of a systematic and simpliﬁed approach to semi-automatic generation of control law parameters for generic ﬁghter aircraft. The investigated method aims to reduce human workload and time spent on complex decision making in the early stages of aircraft development. The method presented is based on gain scheduled LQI-control with piece-wise linear interpolation. A solution to the automated tuning problem of the associated weighting matrices Q and R is investigated. The method is based on an LQ-optimal eigenstructure assignment. However, the derived method suﬀers from problem regarding practical implementation, such as the seemingly narrow LQ-optimal root-loci of the linearized aircraft model.Furthermore, the inherent problem of hidden coupling is discussed in relation to gain scheduled controllers based on conventional series expansion linearization. An alternative linearization method is used in order to circumvent this problem. Moreover, the possible beneﬁts and disadvantages of control allocation is addressed in the context of actuator redundancy. It is concluded that one may achieve a somewhat simpler handling of constraints at the expense of some model accuracy due to the inevitable exclusion of servo dynamics.

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9

Ang, Yang Adrian. "Prediction and analytics of operating parameters on thermoelectric generator energy generation." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3872.

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The efficient use of energy at all stages along the energy supply chain and the utilization of renewable energies are very important elements of a sustainable energy supply system, specially at the conversion from thermal to electrical energy. Converting the low-grade waste heat into electrical power would be useful and effective for several primary and secondary applications. One of the viable means to convert the low-grade waste heat into electrical energy is the use of thermoelectric power conversion. The performance of thermoelectric generators, subjected to thermal effects, can vary considerably depending on the operating conditions, therefore it is necessary to measure and have a better understanding of the characteristics and performance of the thermoelectric generator. It is important to understand the thermoelectric generator’s dynamic behavior and interaction with its operating environmental parameters. Based on this knowledge, it is then significant to develop an effective mathematical model that can provide the user with the most probable outcome of the output voltage. This will contribute to its reliability and calculation to increase the overall efficiency of the system. This thesis provides the transient solution to the three-dimensional heat transfer equation with internal heat generation. It goes on to describes the transfer and generation of heat across the thermoelectric generator with dynamic exchange of heat. This solution is then included in a model in which the thermal masses and the operating environmental parameters of the thermoelectric generator are factored in. The resulting model is created in MATLAB. The comparison with experimental results from a thermoelectric generator system confirms the accuracy of the artificial neural network model. This thesis also presents two practical applications, the prediction of the input parameters with a given output voltage, and sensitivity analysis designed for the model. This is to enable users to customize the thermoelectric generator for their requirements. This allows for better usage of resources eventually.

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10

Zadeh, Ramin Agha. "Performance control of distributed generation using digital estimation of signal parameters." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/47011/1/Ramin_Agha_Zadeh_Thesis.pdf.

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The Queensland University of Technology (QUT) allows the presentation of a thesis for the Degree of Doctor of Philosophy in the format of published or submitted papers, where such papers have been published, accepted or submitted during the period of candidature. This thesis is composed of seven published/submitted papers, of which one has been published, three accepted for publication and the other three are under review. This project is financially supported by an Australian Research Council (ARC) Discovery Grant with the aim of proposing strategies for the performance control of Distributed Generation (DG) system with digital estimation of power system signal parameters. Distributed Generation (DG) has been recently introduced as a new concept for the generation of power and the enhancement of conventionally produced electricity. Global warming issue calls for renewable energy resources in electricity production. Distributed generation based on solar energy (photovoltaic and solar thermal), wind, biomass, mini-hydro along with use of fuel cell and micro turbine will gain substantial momentum in the near future. Technically, DG can be a viable solution for the issue of the integration of renewable or non-conventional energy resources. Basically, DG sources can be connected to local power system through power electronic devices, i.e. inverters or ac-ac converters. The interconnection of DG systems to power system as a compensator or a power source with high quality performance is the main aim of this study. Source and load unbalance, load non-linearity, interharmonic distortion, supply voltage distortion, distortion at the point of common coupling in weak source cases, source current power factor, and synchronism of generated currents or voltages are the issues of concern. The interconnection of DG sources shall be carried out by using power electronics switching devices that inject high frequency components rather than the desired current. Also, noise and harmonic distortions can impact the performance of the control strategies. To be able to mitigate the negative effect of high frequency and harmonic as well as noise distortion to achieve satisfactory performance of DG systems, new methods of signal parameter estimation have been proposed in this thesis. These methods are based on processing the digital samples of power system signals. Thus, proposing advanced techniques for the digital estimation of signal parameters and methods for the generation of DG reference currents using the estimates provided is the targeted scope of this thesis. An introduction to this research – including a description of the research problem, the literature review and an account of the research progress linking the research papers – is presented in Chapter 1. One of the main parameters of a power system signal is its frequency. Phasor Measurement (PM) technique is one of the renowned and advanced techniques used for the estimation of power system frequency. Chapter 2 focuses on an in-depth analysis conducted on the PM technique to reveal its strengths and drawbacks. The analysis will be followed by a new technique proposed to enhance the speed of the PM technique while the input signal is free of even-order harmonics. The other techniques proposed in this thesis as the novel ones will be compared with the PM technique comprehensively studied in Chapter 2. An algorithm based on the concept of Kalman filtering is proposed in Chapter 3. The algorithm is intended to estimate signal parameters like amplitude, frequency and phase angle in the online mode. The Kalman filter is modified to operate on the output signal of a Finite Impulse Response (FIR) filter designed by a plain summation. The frequency estimation unit is independent from the Kalman filter and uses the samples refined by the FIR filter. The frequency estimated is given to the Kalman filter to be used in building the transition matrices. The initial settings for the modified Kalman filter are obtained through a trial and error exercise. Another algorithm again based on the concept of Kalman filtering is proposed in Chapter 4 for the estimation of signal parameters. The Kalman filter is also modified to operate on the output signal of the same FIR filter explained above. Nevertheless, the frequency estimation unit, unlike the one proposed in Chapter 3, is not segregated and it interacts with the Kalman filter. The frequency estimated is given to the Kalman filter and other parameters such as the amplitudes and phase angles estimated by the Kalman filter is taken to the frequency estimation unit. Chapter 5 proposes another algorithm based on the concept of Kalman filtering. This time, the state parameters are obtained through matrix arrangements where the noise level is reduced on the sample vector. The purified state vector is used to obtain a new measurement vector for a basic Kalman filter applied. The Kalman filter used has similar structure to a basic Kalman filter except the initial settings are computed through an extensive math-work with regards to the matrix arrangement utilized. Chapter 6 proposes another algorithm based on the concept of Kalman filtering similar to that of Chapter 3. However, this time the initial settings required for the better performance of the modified Kalman filter are calculated instead of being guessed by trial and error exercises. The simulations results for the parameters of signal estimated are enhanced due to the correct settings applied. Moreover, an enhanced Least Error Square (LES) technique is proposed to take on the estimation when a critical transient is detected in the input signal. In fact, some large, sudden changes in the parameters of the signal at these critical transients are not very well tracked by Kalman filtering. However, the proposed LES technique is found to be much faster in tracking these changes. Therefore, an appropriate combination of the LES and modified Kalman filtering is proposed in Chapter 6. Also, this time the ability of the proposed algorithm is verified on the real data obtained from a prototype test object. Chapter 7 proposes the other algorithm based on the concept of Kalman filtering similar to those of Chapter 3 and 6. However, this time an optimal digital filter is designed instead of the simple summation FIR filter. New initial settings for the modified Kalman filter are calculated based on the coefficients of the digital filter applied. Also, the ability of the proposed algorithm is verified on the real data obtained from a prototype test object. Chapter 8 uses the estimation algorithm proposed in Chapter 7 for the interconnection scheme of a DG to power network. Robust estimates of the signal amplitudes and phase angles obtained by the estimation approach are used in the reference generation of the compensation scheme. Several simulation tests provided in this chapter show that the proposed scheme can very well handle the source and load unbalance, load non-linearity, interharmonic distortion, supply voltage distortion, and synchronism of generated currents or voltages. The purposed compensation scheme also prevents distortion in voltage at the point of common coupling in weak source cases, balances the source currents, and makes the supply side power factor a desired value.

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11

Dye, Kellen. "Implementation of bit-vector variables in a CP solver, with an application to the generation of cryptographic S-boxes." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235772.

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We present a bit-vector variable implementation for the constraint programming (CP) solver Gecode and its application to the problem of finding high-quality cryptographic substitution boxes (S-boxes). S-boxes are a component in some cryptographic protocols, for example DES, which are critical to the strength of the entire system. S-boxes are arrays of bit-vectors, where each bit-vector is itself an array of bits.The desirable properties of an S-box can be described as relationships between its constituent bit-vectors. We represent substitution boxes as arrays of bit-vector variables in Gecode in order to leverage CP techniques for finding high-quality S-boxes. In a CP solver, bit-vectors can alternatively be represented as sets or as arrays of Boolean variables. Experimental evaluation indicates that modeling substitution boxes with bit-vector variables is an improvement over both set- and Boolean-based models. We additionally correct an error in previous work which invalidates the main experimental result, extend a heuristic for evaluating S-box quality, present two symmetries for substitution boxes, define several generic bit-vector propagators, and define propagators for the S-2 and S-7 DES design criteria.

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12

Баранова, Ірина Володимирівна, Ирина Владимировна Баранова, Iryna Volodymyrivna Baranova, and Y. Voitsekhovskyi. "Information Technology for 3D Relief Model Generation By Color Parameters of Pixel." Thesis, Sumy State University, 2017. http://essuir.sumdu.edu.ua/handle/123456789/55764.

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Using of digital maps in simulators will dynamically change the tasks options and improve the quality of military professionals. The paper said information technology to get 3D relief model for digital maps. Created simulator module has a user friendly interface with a large number of configuration options that allow well prepared for raster images for recognition. The generation of digital terrain automatically. The resulting digital map can edit, change display settings, zoom and move in the world coordinate system, add it necessary to vegetation and buildings.

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13

Giffin, Amanda. "Investigation of Operating Parameters Influencing Electrostatic Charge Generation in Gas-Solid Fluidized Beds." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19728.

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Electrostatic charge generation in gas-solid fluidized beds is a significant industrial problem. Associated problems include particle agglomeration and particle wall fouling. In the polymerization industry this may result in "sheets" of fused polymer, due to exothermic reaction causing the melting of the polymer, which can fall off and block the distributor plate disrupting fluidizing gas flow. Additionally, blockage of the catalyst feed or the polymer removal system can take place or the product can become non-uniform. All of these problems require shut-down of the reactor which results in lost production time. While this phenomena has been identified for many years, the mechanisms involved are not well understood, especially wall fouling and the distribution of charge within the bed. Isolation of individual parameters such as hydrodynamics, operating conditions, and material involved is necessary to evaluate how each parameter impacts charge generation during fluidization. In this thesis, the fluidization system consisted of a stainless steel column, two online Faraday cups, and a retractable distributor plate. This system allowed for the simultaneous measurement of charge within different regions of the bed: the entrained fine particles, the particles adhered to the column wall, and the bulk of the bed. Additionally, mass and particle size distributions were measured and images of the layer of particles adhered to the column wall were taken for comparison. This allowed for a charge distribution comparison and evaluation of wall fouling. Three different parameters were investigated: duration of fluidization, column wall material, and relative humidity of fluidizing gas. Fluidization time was studied for 15, 30, 60, 120, 180, and 360 min; relative humidity was investigated for 0%, 20%, 40%, 60%, and 80% relative humidity. Both fluidization time and relative humidity were evaluated at four different fluidization gas velocities, two each in the bubbling and slugging flow regimes. Column wall material was evaluated for a stainless steel and carbon steel column at two gas velocities, one each in the bubbling and slugging flow regimes. Fluidization time was found to influence wall fouling in the bubbling flow regime as the particle layer continued to build as fluidization progressed. In the slugging flow regime, the particle layer developed within 15 minutes of the onset of fluidization. The bubbling flow regime was shown to have a greater capacity for charge generation than the slugging flow regime. This was due to the vigorous mixing in the bubbling flow regime resulting in more particle-particle interactions. Column wall material was shown to influence wall fouling in the slugging flow regime due to the differences in surface roughness of the columns. This was due to the particle-wall contacts resulting in frictional charging which is the predominant charging mechanism in this flow regime. Charge was also impacted in the bubbling flow regime in those particles that were adhered to the column wall. Relative humidity was found to influence wall fouling at the lowest gas velocity tested. However, variations in generation of charge occurred at all fluidization gas velocities tested; the charge-to-mass ratios for the particles adhered to the column wall in the slugging flow regime decreased with high relative humidities. This was due to either the formation of a water film layer on the column wall or instantaneous surface water films on the particles throughout fluidization.

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14

Macabebe, Erees Queen Barrido. "Investigation of device and performance parameters of photovoltaic devices." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/1003.

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In order to investigate the influence of parasitic resistances, saturation current and diode ideality factor on the performance of photovoltaic devices, parameter extraction routines employing the standard iteration (SI) method and the particle swarm optimization (PSO) method were developed to extract the series resistance, shunt resistance, saturation current and ideality factor from the I-V characteristics of solar cells and PV modules. The well-known one- and two-diode models were used to describe the behavior of the I-V curve and the parameters of the models were determined by approximation and iteration techniques. The SI and the PSO extraction programmes were used to assess the suitability of the one- and the two-diode solar cell models in describing the I-V characteristics of mono- and multicrystalline silicon solar cells, CISS- and CIGSS-based solar cells. This exercise revealed that the two-diode model provides more information regarding the different processes involved in solar cell operation. Between the two methods developed, the PSO method is faster, yielded fitted curves with lower standard deviation of residuals and, therefore, was the preferred extraction method. The PSO method was then used to extract the device parameters of CISS-based solar cells with the CISS layer selenized under different selenization process conditions and CIGSS-based solar cells with varying i-ZnO layer thickness. For the CISS-based solar cells, the detrimental effect of parasitic resistances on device performance increased when the temperature and duration of the selenization process was increased. For the CIGSS-based devices, photogeneration improved with increasing i-ZnO layer thickness. At high forward bias, bulk recombination and/or tunneling-assisted recombination were the dominant processes affecting the I-V characteristics of the devices. v Lastly, device and performance parameters of mono-, multicrystalline silicon and CIS modules derived from I-V characteristics obtained under dark and illuminated conditions were analyzed considering the effects of temperature on the performance of the devices. Results showed that the effects of parasitic resistances are greater under illumination and, under outdoor conditions, the values further declined due to increasing temperature. The saturation current and ideality factor also increased under outdoor conditions which suggest increased recombination and, coupled with the adverse effects of parasitic resistances, these factors result in lower FF and lower maximum power point. Analysis performed on crystalline silicon and thin film devices utilized in this study revealed that parameter extraction from I-V characteristics of photovoltaic devices and, in particular, the implementation of PSO in solar cell device parameter extraction developed in this work is a useful characterization technique.

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15

Breglia, Douglas P. "GENERATION OF A 3-D PARAMETRIC SOLID MODEL OF THE HUMAN SPINE USING ANTHROPOMORPHIC PARAMETERS." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1150819095.

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16

Lim, Theam Soon [Verfasser]. "Parameters affecting phage display library design for improved generation of human antibodies / Theam Soon Lim." Berlin : Freie Universität Berlin, 2009. http://d-nb.info/1023748355/34.

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17

Halliday, Matthew. "Characterisation of direct acting oral anticoagulants and their pharmacodynamics on thrombin generation and coagulation parameters." Thesis, Halliday, Matthew (2017) Characterisation of direct acting oral anticoagulants and their pharmacodynamics on thrombin generation and coagulation parameters. Honours thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/39892/.

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Introduction: Vitamin K antagonists (VKA) are historically used to treat thrombosis but newer direct acting oral anticoagulants (DOAC) have been released. DOACs influence laboratory methods that monitor haemostasis, leading to false positives and prolonged clotting results. Trough DOAC concentrations may have less influence at than at peak, but this is unknown. There is speculation that obesity also affects DOAC efficiency. This study sought to validate the effects of two common DOACs, rivaroxaban and apixaban, on 12 laboratory assays at peak and trough concentrations, as well as the influence of obesity on the drugs and assays. Methods: Rivaroxaban (n=20) and apixaban (n=21) patients had samples collected immediately before their next dose, and 3 hours after to provide peak and trough. Healthy controls (n=20) provided a sample at one-time point. Relevant medical histories and demographics, including BMI, were collected after obtaining informed consent. Samples underwent coagulation and thrombophilia panels as well as thrombin antithrombin complex, prothrombin fragments 1+2, and thrombin generation assays (TGA). Statistical analysis was performed between peak and controls, peak and trough, and all BMI groups. Results: Significant prolongations were found with the prothrombin time (PT), activated partial thromboplastin time (APTT), TGA, and false positives for the dilute Russell viper venom time (DRVVT) by both rivaroxaban and apixaban. Apixaban was less potent than rivaroxaban with significant differences only between peak and trough for PT, and APTT. Only two results were influenced by weight; the APTT with rivaroxaban and free protein S for the controls. Conclusion: Rivaroxaban and apixaban are similar drugs but impact the assays differently due to dosage, half-life, and rate activity. Both influence assays more at peak than trough, but trough is still notably influenced compared to the controls. This study highlights the influence of these drugs on most tests performed in a haemostasis laboratory.

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18

Palfelt, Alexander, Wilhelm Thunberg, and Anders Winka. "Determining the Sensitivity of Reactor Parameters in a Sodium Cooled Fast Reactor." Thesis, Uppsala universitet, Tillämpad kärnfysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413073.

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The sensitivity of two operational output parameters, criticality and isotopic composition during burnup, to specific design and operational reactor parameters in a Sodium Cooled Fast Reactor, is investigated. The computational simulation tool Serpent is used. The parameters varied include Uranium enrichment, Plutonium content, rod thickness, fuel temperature, and sodium density. In burnup, the development of the fraction of fissile isotopes, isotopes used for measurements, the isotopic composition of Plutonium, and isotopes that complicate fuel reprocessing is displayed. A surrogate model, optimized for use in determining how criticality develops between data points, is used. The results are displayed as plots created in Matlab. The results are discussed, with a focus on how large an effect varying different parameters have on different outputs related to the reactor's operation. It is concluded that the Plutonium content has the largest effect on the isotopic composition and that, based on the performed simulations, MOX fuel is potentially safer than Zirconium alloy fuel in a practical setting.

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19

Oliveira, Vanessa Amaral de. "Influence of processing parameters on the generation and propagation of electrically active crystalline defects in monolike silicon." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI021.

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Le nouveau procédé d’élaboration par solidification dirigée de lingots de Si quasi-monocristallin (« monolike ») offre une alternative séduisante à l’utilisation plus coûteuse de monocristaux pour la fabrication de cellules photovoltaïques à architecture avancée et haut rendement. Toutefois, la présence locale de zones de fortes densités de dislocations entraîne une dispersion des rendements obtenus.Cette Thèse présente une analyse détaillée des mécanismes de formation des structures de dislocations lors de la cristallisation monolike et de leur influence sur les propriétés électriques du matériau. Des conclusions pratiques en sont tirées pour l’amélioration du procédé.Des expériences de cristallisation en four pilote ont été réalisées en faisant varier les paramètres tenant à la mise en œuvre du pavage de germes et à la réutilisation de ceux-ci, à l’orientation cristallographique de croissance, et au dopage en élément durcissant (Ge). Des tests complémentaires de recuit et de flexion 4 points à haute température ont été utilisés pour analyser l’influence du niveau de contrainte et du temps.Une caractérisation avancée des structures de dislocations a été réalisée par imagerie X synchrotron. En arrière du front de croissance, les dislocations s’organisent en structures cellulaires qui correspondent à l’état final de fluage stationnaire. Les dislocations qui émergent au front peuvent, par accumulation locale, générer des domaines désorientés de forme conique, qui présentent des angles de rotation croissants autour de la direction de solidification, et s’étendent latéralement lors de la progression du front. Les fortes activités recombinantes de ces défauts ont été caractérisées par LBIC et Photoluminescence. Un choix approprié des orientations et des conditions de mise en œuvre des germes permet de s’affranchir des défauts initiés à l’interface germes/lingot. Toutefois, de tels défauts peuvent aussi être générés par accumulation locale de dislocations en partie supérieure des lingots sous l’effet de contraintes élevées.Ces derniers défauts n’ont pas été observés dans les lingots cristallisés dans les directions <110> et <112>, ce qui constitue un avantage par rapport aux lingots <100>. Par contre, des macles et sous-joints se sont propagés à partir des joints de grains de rotation créés volontairement, de sorte que l’effet de l’angle de rotation reste à analyser. Enfin, l’addition de germanium s’est révélée très efficace pour ralentir la multiplication des dislocations lors de tests de flexion sous faibles contraintes. Toutefois, son application à la cristallisation nécessitera une meilleure planéité du front de cristallisation et un brassage forcé du bain pour éviter une ségrégation radiale de Ge. L’utilisation d’autres éléments durcissants est également envisagée
The new generation of directionally solidified “monolike” Si ingots presents an attractive alternative to high-cost monocrystals for the manufacture of high performance solar cells with advanced architecture. However, local zones with high densities of dislocations still affect the overall solar cell efficiency.In the present work, the mechanisms of formation of dislocations structures during monolike growth and their influence on the electrical properties of the material were analyzed, and practical conclusions were drawn for the improvement of the process.Pilot scale crystal growth experiments were performed with varying parameters related to seed pavement and seed recycling, crystallographic orientation of the growth, and doping with a strengthening element (Ge). Complementary annealing and 4-point bending tests at high temperature were used to analyze the influence of stress level and time under stress.Advanced structural characterization of dislocations structures was performed by synchrotron X-ray imaging. Behind the growth front, dislocations organize in cellular patterns which correspond to a quasi-stationary creep stage, reached in the solid after long time under stress at high temperature. Dislocations that emerge at the growth front develop, from local sources, cone-shaped misoriented domains, which present increasing tilt around the growth axis and expand laterally as growth proceeds. Characterization by LBIC and Photoluminescence showed that these defects have the highest recombination activities. The sources of these defects located at the seed ingot interface can be suppressed by proper choice of seeds orientations and arrangement. However, another source is bunching of dislocations at the growth front under the higher stresses upper in the ingot.In <110> and <112> grown ingots, dislocation bunching was not observed inside the monocrystalline parts, which shows an advantage of these orientations over <100>. On another hand, twins and sub-grain boundaries propagated from higher angle grain boundaries with these growth directions, and further studies are needed to prevent the generation of such defects. Finally, Ge doping was effective to reduce dislocations multiplication in bending under low stresses. However, its application to crystal growth will require a planar growth interface, and forced melt mixing to avoid Ge radial segregation. New researches inspired by the addition of strengthening elements are now in development

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20

Bilitski, James A. "Evolutionary Algorithm for Generation of Air Pressure and Lip Pressure Parameters for Automated Performance of Brass Instruments." NSUWorks, 2006. http://nsuworks.nova.edu/gscis_etd/414.

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The artificial mouth is a robotic device that simulates a human mouth. It consists of moveable lips and an adjustable air supply. The uses of an artificial mouth include research for physical modeling of the lips and automatic performance. Automatic performance of a musical instrument is when an instrument is played without the direct interaction of a human. Typically mechanics and robotics are used instead of a human. In this study the use of a genetic algorithm to compute air pressure and lip pressure values so that the artificial mouth can correctly play five notes on a brass instrument is investigated. In order to properly playa brass instrument, a player must apply proper tension between the lips and apply proper airflow so that the lips vibrate at the proper frequency. A player changes the notes on a brass instrument by depressing keys and changing lip pressure and air flow. This study investigated a machine learning approach to finding lip pressure and air pressure parameters so that an artificial mouth could play five notes of a scale on a trumpet. A fast search algorithm was needed because it takes about 4 seconds to measure the frequency produced by each combination of pressure parameters. This measurement is slow because of the slow moving mechanics of the system and a delay produced while the notes are measured for pitch. Two different mouthpieces were used to investigate the ability to adapt to different mouthpieces. The algorithm started with a randomly generated population and evolved the lip pressure and air pressure parameters with an evolutionary algorithm using crossover and mutation designed for the knowledge scheme in this application. The efficiency of this algorithm was compared to an exhaustive search. Experimentation was performed using various combinations of genetic parameters including population size, crossover rate, and mutation rate. The evolutionary search was shown to be about 10 times faster than the exhaustive search because the evolutionary algorithm searches only very small portion of the search space. A recommendation for future research is to conduct further experimentation to determine more optimal crossover and mutation rates.

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21

Shiyani, Dhaval. "Study of the Effects of Geometric Parameters and Yaw Angle on Drag Generation in Clean Rectangular Cavities." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1523630270514358.

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22

Mishra, Brijes. "Analysis of cutting parameters and heat generation on bits of a continuous miner using numerical and experimental approach /." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5514.

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Thesis (Ph. D.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains ix, 104 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 94-96).

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23

Fonari, Alexandr. "Theoretical description of charge-transport and charge-generation parameters in single-component and bimolecular charge-transfer organic semiconductors." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54323.

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In this dissertation, we employ a number of computational methods, including Ab Initio, Density Functional Theory, and Molecular Dynamics simulations to investigate key microscopic parameters that govern charge-transport and charge-generation in single-component and bimolecular charge-transfer organic semiconductors. First, electronic (transfer integrals, bandwidths, effective masses) and electron-phonon couplings of single-component organic semiconductors are discussed. In particular, we evaluate microscopic charge-transport parameters in a series of nonlinear acenes with extended pi-conjugated cores. Our studies suggest that high charge-carrier mobilities are expected in these materials, since large electronic couplings are obtained and the formation of self-localized polarons due to local and nonlocal electron-phonon couplings is unlikely. Next, we evaluate charge detrapping due to interaction with intra-molecular crystal vibrations in order to explain changes in experimentally measured electric conductivity generated by pulse excitations in the IR region of a photoresistor based on pentacene/C60 thin film. Here, we directly relate the nonlocal electron-phonon coupling constants with variations in photoconductivity. In terms of charge-generation from an excited manifold, we evaluate the modulation of the state couplings between singlet and triplet excited states due to crystal vibrations, in order to understand the effect of lattice vibrations on singlet fission in tetracene crystal. We find that the state coupling between localized singlet and correlated triplet states is much more strongly affected by the dynamical disorder due to lattice vibrations than the coupling between the charge-transfer singlet and triplet states. Next, the impact of Hartree-Fock exchange in the description of transport properties in crystalline organic semiconductors is discussed. Depending on the nature of the electronic coupling, transfer integrals and bandwidths can show a significant increase as a function of the amount of the Hartree-Fock exchange included in the functional. Similar trend is observed for lattice relaxation energy. It is also shown that the ratio between electronic coupling and lattice relaxation energy is practically independent of the amount of the Hartree-Fock exchange, making this quantity a good candidate for incorporation into tight-binding transport models. We also demonstrate that it is possible to find an amount of the Hartree-Fock exchange that recovers (quasi-particle) band structure obtained from a highly accurate G0W0 approach. Finally, a microscopic understanding of a phase transition in charge-carrier mobility from temperature independent to thermally activated in stilbene-tetrafluoro-tetracyanoquinodimethane crystal is provided.

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24

Maquart, Tristan. "Trivariate models generation from unstructured surface manifolds for isogeometric analysis : Application to reduced order modeling with geometric parameters." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI033.

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Ce travail présente un cadre générique pour la construction de maillages isogéométriques volumiques à partir d'une géométrie complexe avec une topologie arbitraire pour des applications relatives aux modèles d'ordres réduits. En effet, les maillages structurés tels que les maillages isogéométriques ou hexahédriques sont difficiles à obtenir de manière automatique. Les analyses statistiques de formes et les modèles d'ordres réduits nécessitent des données structurées et ordonnées pour être construits efficacement. Pour ce faire, nous utilisons les limites du modèle solide triangulé, la B-Rep CAD (Boundary Representation in Computer Aided Design). Tout d'abord, cette thèse inclut une intégration d'un algorithme de décomposition en pantalons et en cuboïdes prenant en compte les caractéristiques géométriques. La décomposition en cuboïdes divise une surface en un ensemble de patchs quadrilatéraux qui peuvent aider à définir un volume associé. Des champs de croix (cross fields), c'est-à-dire des champs de directions à 4 symétries, sont utilisés pour guider une paramétrisation globale alignée de la surface. Ce paramétrage est optimisé afin de minimiser la distorsion des éléments. Le processus d'optimisation est pensé pour concevoir des champs de croix avec des contraintes topologiques et géométriques. En utilisant la décomposition optimisée en cuboïdes, une structure volumétrique est extraite. Sur la base de la paramétrisation globale et de la structure volumétrique précédemment calculée, une paramétrisation isogéométrique trivariée est déduite. Les propriétés topologiques invariantes sont analysées tout au long du processus proposé. Pour finir, pour différentes occurrences géométriques de même topologie mais possédant des géométries différentes, notre méthode permet d'avoir la même représentation : des maillages isotopologiques isogéométriques trivariés détenant la même connectivité. L'efficacité et la robustesse de l'approche proposée sont illustrées par plusieurs exemples de modèles d'ordres réduits en utilisant l'IGA (IsoGeometric Analysis)
This work presents a generic framework to construct trivariate isogeometric meshes of complicated geometry and arbitrary topology required for reduced order model applications. Indeed, structured meshes such as isogeometric or pure hexahedral ones are difficult to obtain in an automatic manner. Statistical shape analysis and reduced order modeling require structured and ordered data to be efficient. For that purpose, we use the triangulated solid 3D model's boundary provided from B-Rep CAD (Boundary-Representation in Computer Aided Design) models. Firstable, the workflow includes an integration of a geometry-feature-aware pants-to-cuboids decomposition algorithm. The input triangulated mesh is decomposed into a set of cuboids in two steps: pants decomposition and cuboid decomposition. Cuboid decomposition splits a surface into a set of quadrilateral patches which can define a volumetric layout of the associated boundary surface. Cross fields, i.e., 4-symmetry direction fields are used to guide a surface aligned global parameterization. Optimizing this parameterization, patches of the quadrilateral layout inherited from the cuboid decomposition are re-positioned on the surface in a way to achieve low overall distortion. The optimization process is thought to design cross fields with topological and geometrical constraints. Using the optimized cuboid decomposition, a volumetric layout is extracted. Based on the global parameterization and the structured volumetric layout previously computed, a trivariate isogeometric parameterization is deducted. Learning generalized forms of theorems in the topology field, invariant topological properties are analyzed throughout the proposed process. To finish, for different geometrical instances with the same topology but different geometries, our method allows to have the same representation: trivariate isogeometric isotopological meshes holding the same connectivity. The efficiency and the robustness of the proposed approach are illustrated through several examples of reduced order models using IGA (IsoGeometric Analysis)

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25

Kavas, Musa Supervisor :. Yücel Meral. "Optimization of tissue culture, generation and agrobacterium mediated transformation parameters in winter wheat cultivars (Kızıltan-91 and Bezostaja-01)." Ankara : METU, 2005. http://etd.lib.metu.edu.tr/upload/3/12606523/index.pdf.

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26

Abdukadyrova, I. Kh. "Influence of high reactor irradiation on some parameters of Al203 crystals and process generation of a several points nanodefects." Thesis, Sumy State University, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20873.

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In this connection the peculiarities of radiation effect on lattice parameters, form and position of several reflections, reflection coefficient and frequency of valence and deformation oscillations of Al-O bonds, optical characteristics of the oxide aluminium Al2O3 were studied with techniques of X-diffraction, absortion-luminescenke and IRreflection spectroscopy. The characteristic features of the process of radiation-defect formation and generation of some points nanodefects, change in the structural, optical properties of Al2O3 crystals exposed to gamma and reactor radiation have been investigated by spectroscopic methods. The dose dependence’s of the generation in crystals the color and luminescence centers, nanodefects - type F- and F-aggregate, change of the structural parameters was determined. For example, in work presented of temperaturedose dependence on the intensity of the 330, 420 nm bands in FL and GL spectrum of crystals. As the T= 600-7000C and fluence 1.1016 cm-2 - 1.1019 cm-2 of intensity this bands increasing (nanodefects - F+ centers) was can see. In this paper was given dose dependence of generation on the oxide in the absorption spectra a bands 257 and 358 nm (nanodefects of a type F- and F-aggregate defects). The possible mechanism of damage structure of a samples irradiated in a reactor is discussed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20873

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27

Joshi, Abhishek. "ROLE OF WEAK ZONE GEOMETRY AND RHEOLOGY IN THE GENERATION OF INTRAPLATE SEISMICITY." UKnowledge, 2005. http://uknowledge.uky.edu/gradschool_theses/346.

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In intraplate seismic zones (e.g. the New Madrid Seismic Zone, NMSZ, in the southcentral United States), the source of stress that drives earthquake is very complex. Data from the NMSZ indicate 3 earthquake of magnitude M~7, occurring at an approximate interval of 500 years during the last 2000 years. One hypothesis that satisfies these conditions proposes that short-lived bursts of earthquakes may result from perturbations in the local or regional stress field. This causes relaxation of a lower crustal weak zone which drive repeated earthquakes. The number of earthquakes is dependent on the geometry and rheology of the weak zone. Using finite element techniques which employ contact surfaces to model discrete faulting events and a maximum shear stress criteria evaluated at each node. We investigate the relevant parameter space, as it affects the concentration of stress at the base of the seismogenic fault and the number of earthquakes generated over a given time interval. Parameters that can be varied include earthquake stress drop, background tectonic stress, and maximum shear stress at failure. Results show that solutions are non-unique. With the addition of existing observational evidence, however, we can place bounds on the range of parameters which satisfy above observations.

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28

Simon, Michael. "On the evaluation of spectral effects on photovoltaic modules performance parameters and hotspots in solar cells." Thesis, University of Fort Hare, 2009. http://hdl.handle.net/10353/257.

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The performance of photovoltaic (PV) modules in terms of their ability to convert incident photon to electrical energy (efficiency) depends mostly on the spectral distribution of incident radiation from the sun. The incident spectrum finally perceived by the module depends strongly on the composition of the medium in which it has traveled. The composition of the earth’s atmosphere, which includes, amongst others, water vapour, gases such as carbon dioxide and oxygen, absorbs or scatters some of the sunlight. The incident solar spectrum is also modified by the diffuse aspect of radiation from the sky which strongly depends on aerosol concentration, cloudiness and local reflection of the earth’s surface. Although it is well known that the changes in outdoor spectrum affect device performance, little work has been conducted to support this theory. This is probably due to lack of spectral data or in certain instances where data is available, little knowledge of interpreting that data. The outdoor spectral data that one obtains in the field does not come clearly for just simple interpretation. Different analytical interpretation procedures have been proposed, all trying to explain and quantify the spectral influence on PV devices. In this study an assessment methodology for evaluating the effects of outdoor spectra on device performance parameters during the course of the day, seasons and or cloudy cover has been developed. The methodology consists of developing a device dependant concept, Weighted Useful Fraction (WUF) using the outdoor measured spectral data. For measuring PV module’s performance parameters, a current-voltage (I-V) tester was developed in order to monitor the performance of six different module technologies. The Gaussian distribution was used to interpret the data. For hot-spot analysis, different techniques were used, which include Infrared thermographic technique for identifying the hot-spots in the solar cells, SEM and EDX techniques. The AES technique was also used in order to identify other elements at hot-spots sites that could not be detected by the EDX technique. iii Results obtained indicate that multicrystalline modules performance is affected by the changes in the outdoor spectrum during summer or winter seasons. The modules prefer a spectrum characterized by WUF = 0.809 during summer season. This spectrum corresponds to AM 2.19 which is different from AM 1.5 used for device ratings. In winter, the mc-Si module’s WUF (0.7125) peaks at 13h00 at a value corresponding to AM 1.83. Although these devices have a wider wavelength range, they respond differently in real outdoor environment. Results for mono – Si module showed that the device performs best at WUF = 0.6457 which corresponds to AM 1.83 during summer season, while it operates optimally under a winter spectrum indicated by WUF of 0.5691 (AM2.58). The seasonal changes resulted in the shift in WUF during day time corresponding to the “preferred” spectrum. This shift indicates that these devices should be rated using AM values that correspond to the WUF values under which the device operates optimally. For poly-Si, it was also observed the WUF values are lower than the other two crystalline-Si counterparts. The pc-Si was observed to prefer a lower AM value indicated by WUF = 0.5813 during winter season while for summer it prefers a spectrum characterized by WUF = 0.5541 at AM 3.36. The performance of the single junction a-Si module degraded by 67 percent after an initial outdoor exposure of 16 kWh/m² while the HIT module did not exhibit the initial degradation regardless of their similarities in material composition. It was established that the WUF before degradation peaks at 15h00 at a value of 0.7130 corresponding to AM 4.50 while the WUF after degradation “prefers” the spectrum (WUF = 0.6578) experienced at 15h30 corresponding to AM value of 5.57. Comparing the before and after degradation scenarios of a-Si:H, it was observed that the device spends less time under the red spectrum which implies that the device “prefers” a full spectrum to operate optimally. The degradation of a-Si:H device revealed that the device spectral response was also shifted by a 7.7 percent after degradation. A higher percentage difference (61.8 percent) for spectral range for the HIT module is observed, but with no effects on device parameters. Seasonal changes (summer/winter) resulted in the outdoor spectrum of CuInSe2 to vary by WUF = 1.5 percent, which resulted in the decrease in Isc. This was ascertained by iv analyzing the percentage change in WUF and evaluating the corresponding change in Isc. The analysis showed that there was a large percentage difference of the module’s Isc as the outdoor spectrum changed during the course of the day. This confirmed that the 17 percent decrease in Isc was due to a WUF of 1.5 percent. In mc-Si solar cells used in this study, it was found that elemental composition across the entire solar cell was not homogenously distributed resulting in high concentration of transition metals which were detected at hot spot areas. The presence of transition metals causes hot-spot formation in crystalline solar cells. Although several transition elements exist at hot-spot regions, the presence of oxygen, carbon, iron and platinum was detected in high concentrations. From this study, it is highly recommended that transition elements and oxygen must be minimized so as to increase the life expectancy of these devices and improve overall systems reliability

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29

Bühle, Lutz [Verfasser]. "Biological and chemical parameters and life cycle assessment of the integrated generation of solid fuel and biogas from biomass / Lutz Bühle." Kassel : Kassel University Press, 2014. http://d-nb.info/1057854662/34.

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30

Kalidindi, Varahalaraju. "OPTIMIZATION OF DRILL DESIGN AND COOLANT SYSTEMS DURING DENTAL IMPLANT SURGERY." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/314.

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Dental implants are an effective alternative for the replacement of missing teeth. The success of the implant depends on how well a bone heals around the implant, a process known as osseointegration. However, excessive heat generated during the bone drilling will cause cell death and may prevent osseointegration of the implant, resulting in early failure. There are many factors which contribute to the heat generation during drilling. Experiments were carried out to investigate the affect of variable drilling factors on heat generation during drilling operation. Natural bone is not an ideal material for such research, as it varies widely in density and other parameters of interest.. It would be desirable to have a more uniform and consistent material to use in such studies. However, such a material must be similar to bone to allow the results to be extrapolated to the clinical situation. The current study describes and validates a model for use in such studies. Polymethylmethacrylate (PMMA) is the material chosen for our studies. A theoretical model was developed to study the effect of different drilling parameters on temperature rise during drilling operations. Comparison of observed results obtained from experiments was made with the results from theoretical study. Comparison of results for PMMA and human bone are also shown explaining how PMMA material can be substituted for human bone. The results suggest that the PMMA model is an acceptable surrogate for bone in such studies.

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Almatouq, Abdullah. "Study of the parameters for optimisation of the design and performance of bio-electrochemical systems for energy/hydrogen generation and resource recovery." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/100405/.

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This study focused on the exploration, assessment and experimental investigation of bio-electrochemical systems (BES) for concurrent phosphorus (P) recovery and energy generation/hydrogen (H2) production. The main aim was to study and understand the parameters for optimisation of the design and the performance of BESs for concurrent phosphorus recovery and energy generation/hydrogen production. In total, four dual chamber bio-electrochemical systems (Microbial Fuel Cells (MFCs) and Microbial Electrolysis Cells (MECs)) were used to investigate the impacts of key design and operational conditions on BES performance. P was precipitated successfully as struvite in both MFCs and MECs. The MFCs and MECs achieved a maximum P precipitation efficiency of 90% and 95% with a maximum columbic efficiency of 10% and 51% respectively. The MFCs and MECs achieved an average of 80 % and 70 % COD removal efficiency respectively, which confirms the ability of these systems to be used in wastewater treatment. Deterioration in both reactors occurred due to P precipitation on the cathode surface and the membrane. The three operational parameters (influent COD, cathode aeration flow rate, and external resistance) were found to have significant impacts on MFC performance and P recovery. In addition, applied voltage and influent COD had significant effects on MEC performance and P recovery. Results were supported through statistical analysis and optimisation modelling using full factorial design, central composite design, and response surface methodology. Generally, results have shown that MFCs and MECs have the potential to concurrently recover P, treat wastewater, and generate electricity/produce H2. Further research is needed to enhance the performance of MFCs for energy generation and MECs for H2 production in addition to P recovery and minimising scaling on electrodes. The results of this study increase the understanding of P recovery mechanisms in MFCs and MECs and can contribute to future BES research. Moreover, the results will help in selecting the optimum operational parameters of BESs depending on the applications and process requirements. Applying BESs in wastewater treatment plants will reduce energy consumption and, at the same time, find an alternative source of P.

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Mesado, Melia Carles. "Uncertainty Quantification and Sensitivity Analysis for Cross Sections and Thermohydraulic Parameters in Lattice and Core Physics Codes. Methodology for Cross Section Library Generation and Application to PWR and BWR." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/86167.

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This PhD study, developed at Universitat Politècnica de València (UPV), aims to cover the first phase of the benchmark released by the expert group on Uncertainty Analysis in Modeling (UAM-LWR). The main contribution to the benchmark, made by the thesis' author, is the development of a MATLAB program requested by the benchmark organizers. This is used to generate neutronic libraries to distribute among the benchmark participants. The UAM benchmark pretends to determine the uncertainty introduced by coupled multi-physics and multi-scale LWR analysis codes. The benchmark is subdivided into three phases: 1. Neutronic phase: obtain collapsed and homogenized problem-dependent cross sections and criticality analyses. 2. Core phase: standalone thermohydraulic and neutronic codes. 3. System phase: coupled thermohydraulic and neutronic code. In this thesis the objectives of the first phase are covered. Specifically, a methodology is developed to propagate the uncertainty of cross sections and other neutronic parameters through a lattice physics code and core simulator. An Uncertainty and Sensitivity (U&S) analysis is performed over the cross sections contained in the ENDF/B-VII nuclear library. Their uncertainty is propagated through the lattice physics code SCALE6.2.1, including the collapse and homogenization phase, up to the generation of problem-dependent neutronic libraries. Afterward, the uncertainty contained in these libraries can be further propagated through a core simulator, in this study PARCSv3.2. The module SAMPLER -available in the latest release of SCALE- and DAKOTA 6.3 statistical tool are used for the U&S analysis. As a part of this process, a methodology to obtain neutronic libraries in NEMTAB format -to be used in a core simulator- is also developed. A code-to-code comparison with CASMO-4 is used as a verification. The whole methodology is tested using a Boiling Water Reactor (BWR) reactor type. Nevertheless, there is not any concern or limitation regarding its use in any other type of nuclear reactor. The Gesellschaft für Anlagen und Reaktorsicherheit (GRS) stochastic methodology for uncertainty quantification is used. This methodology makes use of the high-fidelity model and nonparametric sampling to propagate the uncertainty. As a result, the number of samples (determined using the revised Wilks' formula) does not depend on the number of input parameters but only on the desired confidence and uncertainty of output parameters. Moreover, the output Probability Distribution Functions (PDFs) are not subject to normality. The main disadvantage is that each input parameter must have a pre-defined PDF. If possible, input PDFs are defined using information found in the related literature. Otherwise, the uncertainty definition is based on expert judgment. A second scenario is used to propagate the uncertainty of different thermohydraulic parameters through the coupled code TRACE5.0p3/PARCSv3.0. In this case, a PWR reactor type is used and a transient control rod drop occurrence is simulated. As a new feature, the core is modeled chan-by-chan following a fully 3D discretization. No other study is found using a detailed 3D core. This U&S analysis also makes use of the GRS methodology and DAKOTA 6.3.
Este trabajo de doctorado, desarrollado en la Universitat Politècnica de València (UPV), tiene como objetivo cubrir la primera fase del benchmark presentado por el grupo de expertos Uncertainty Analysis in Modeling (UAM-LWR). La principal contribución al benchmark, por parte del autor de esta tesis, es el desarrollo de un programa de MATLAB solicitado por los organizadores del benchmark, el cual se usa para generar librerías neutrónicas a distribuir entre los participantes del benchmark. El benchmark del UAM pretende determinar la incertidumbre introducida por los códigos multifísicos y multiescala acoplados de análisis de reactores de agua ligera. El citado benchmark se divide en tres fases: 1. Fase neutrónica: obtener los parámetros neutrónicos y secciones eficaces del problema específico colapsados y homogenizados, además del análisis de criticidad. 2. Fase de núcleo: análisis termo-hidráulico y neutrónico por separado. 3. Fase de sistema: análisis termo-hidráulico y neutrónico acoplados. En esta tesis se completan los principales objetivos de la primera fase. Concretamente, se desarrolla una metodología para propagar la incertidumbre de secciones eficaces y otros parámetros neutrónicos a través de un código lattice y un simulador de núcleo. Se lleva a cabo un análisis de incertidumbre y sensibilidad para las secciones eficaces contenidas en la librería neutrónica ENDF/B-VII. Su incertidumbre se propaga a través del código lattice SCALE6.2.1, incluyendo las fases de colapsación y homogenización, hasta llegar a la generación de una librería neutrónica específica del problema. Luego, la incertidumbre contenida en dicha librería puede continuar propagándose a través de un simulador de núcleo, para este estudio PARCSv3.2. Para el análisis de incertidumbre y sensibilidad se ha usado el módulo SAMPLER -disponible en la última versión de SCALE- y la herramienta estadística DAKOTA 6.3. Como parte de este proceso, también se ha desarrollado una metodología para obtener librerías neutrónicas en formato NEMTAB para ser usadas en simuladores de núcleo. Se ha realizado una comparación con el código CASMO-4 para obtener una verificación de la metodología completa. Esta se ha probado usando un reactor de agua en ebullición del tipo BWR. Sin embargo, no hay ninguna preocupación o limitación respecto a su uso con otro tipo de reactor nuclear. Para la cuantificación de la incertidumbre se usa la metodología estocástica Gesellschaft für Anlagen und Reaktorsicherheit (GRS). Esta metodología hace uso del modelo de alta fidelidad y un muestreo no paramétrico para propagar la incertidumbre. Como resultado, el número de muestras (determinado con la fórmula revisada de Wilks) no depende del número de parámetros de entrada, sólo depende del nivel de confianza e incertidumbre deseados de los parámetros de salida. Además, las funciones de distribución de probabilidad no están limitadas a normalidad. El principal inconveniente es que se ha de disponer de las distribuciones de probabilidad de cada parámetro de entrada. Si es posible, las distribuciones de probabilidad de entrada se definen usando información encontrada en la literatura relacionada. En caso contrario, la incertidumbre se define en base a la opinión de un experto. Se usa un segundo escenario para propagar la incertidumbre de diferentes parámetros termo-hidráulicos a través del código acoplado TRACE5.0p3/PARCSv3.0. En este caso, se utiliza un reactor tipo PWR para simular un transitorio de una caída de barra. Como nueva característica, el núcleo se modela elemento a elemento siguiendo una discretización totalmente en 3D. No se ha encontrado ningún otro estudio que use un núcleo tan detallado en 3D. También se usa la metodología GRS y el DAKOTA 6.3 para este análisis de incertidumbre y sensibilidad.
Aquest treball de doctorat, desenvolupat a la Universitat Politècnica de València (UPV), té com a objectiu cobrir la primera fase del benchmark presentat pel grup d'experts Uncertainty Analysis in Modeling (UAM-LWR). La principal contribució al benchmark, per part de l'autor d'aquesta tesi, es el desenvolupament d'un programa de MATLAB sol¿licitat pels organitzadors del benchmark, el qual s'utilitza per a generar llibreries neutròniques a distribuir entre els participants del benchmark. El benchmark del UAM pretén determinar la incertesa introduïda pels codis multifísics i multiescala acoblats d'anàlisi de reactors d'aigua lleugera. El citat benchmark es divideix en tres fases: 1. Fase neutrònica: obtenir els paràmetres neutrònics i seccions eficaces del problema específic, col¿lapsats i homogeneïtzats, a més de la anàlisi de criticitat. 2. Fase de nucli: anàlisi termo-hidràulica i neutrònica per separat. 3. Fase de sistema: anàlisi termo-hidràulica i neutrònica acoblats. En aquesta tesi es completen els principals objectius de la primera fase. Concretament, es desenvolupa una metodologia per propagar la incertesa de les seccions eficaces i altres paràmetres neutrònics a través d'un codi lattice i un simulador de nucli. Es porta a terme una anàlisi d'incertesa i sensibilitat per a les seccions eficaces contingudes en la llibreria neutrònica ENDF/B-VII. La seua incertesa es propaga a través del codi lattice SCALE6.2.1, incloent les fases per col¿lapsar i homogeneïtzar, fins aplegar a la generació d'una llibreria neutrònica específica del problema. Després, la incertesa continguda en la esmentada llibreria pot continuar propagant-se a través d'un simulador de nucli, per a aquest estudi PARCSv3.2. Per a l'anàlisi d'incertesa i sensibilitat s'ha utilitzat el mòdul SAMPLER -disponible a l'última versió de SCALE- i la ferramenta estadística DAKOTA 6.3. Com a part d'aquest procés, també es desenvolupa una metodologia per a obtenir llibreries neutròniques en format NEMTAB per ser utilitzades en simuladors de nucli. S'ha realitzat una comparació amb el codi CASMO-4 per obtenir una verificació de la metodologia completa. Aquesta s'ha provat utilitzant un reactor d'aigua en ebullició del tipus BWR. Tanmateix, no hi ha cap preocupació o limitació respecte del seu ús amb un altre tipus de reactor nuclear. Per a la quantificació de la incertesa s'utilitza la metodologia estocàstica Gesellschaft für Anlagen und Reaktorsicherheit (GRS). Aquesta metodologia fa ús del model d'alta fidelitat i un mostreig no paramètric per propagar la incertesa. Com a resultat, el nombre de mostres (determinat amb la fórmula revisada de Wilks) no depèn del nombre de paràmetres d'entrada, sols depèn del nivell de confiança i incertesa desitjats dels paràmetres d'eixida. A més, las funcions de distribució de probabilitat no estan limitades a la normalitat. El principal inconvenient és que s'ha de disposar de les distribucions de probabilitat de cada paràmetre d'entrada. Si és possible, les distribucions de probabilitat d'entrada es defineixen utilitzant informació trobada a la literatura relacionada. En cas contrari, la incertesa es defineix en base a l'opinió d'un expert. S'utilitza un segon escenari per propagar la incertesa de diferents paràmetres termo-hidràulics a través del codi acoblat TRACE5.0p3/PARCSv3.0. En aquest cas, s'utilitza un reactor tipus PWR per simular un transitori d'una caiguda de barra. Com a nova característica, cal assenyalar que el nucli es modela element a element seguint una discretizació totalment 3D. No s'ha trobat cap altre estudi que utilitze un nucli tan detallat en 3D. També s'utilitza la metodologia GRS i el DAKOTA 6.3 per a aquesta anàlisi d'incertesa i sensibilitat.¿
Mesado Melia, C. (2017). Uncertainty Quantification and Sensitivity Analysis for Cross Sections and Thermohydraulic Parameters in Lattice and Core Physics Codes. Methodology for Cross Section Library Generation and Application to PWR and BWR [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86167
TESIS

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33

Roy, Mousumi. "Front-end considerations for next generation communication receivers." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/frontend-considerations-for-next-generation-communication-receivers(636dc047-7772-46c3-b049-183d3af2a7bb).html.

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The ever increasing diversity in communication systems has created a demand for constant improvements in receiver components. This thesis describes the design and characterisation of front-end receiver components for various challenging applications, including characterisation of low noise foundry processes, LNA design and multi-band antenna design. It also includes a new theoretical analysis of noise coupling in low noise phased array receivers.In LNA design much depends on the choice of the optimum active devices. A comprehensive survey of the performance of low noise transistors is therefore extremely beneficial. To this end a comparison of the DC, small-signal and noise behaviours of 10 state-of-the-art GaAs and InP based pHEMT and mHEMT low noise processes has been carried out. Their suitability in LNA designs has been determined, with emphasis on the SKA project. This work is part of the first known detailed investigation of this kind. Results indicate the superiority of mature GaAs-based pHEMT processes, and highlight problems associated with the studied mHEMT processes. Two of the more promising processes have then been used to design C-band and UHF-band MMIC LNAs. A new theoretical analysis of coupled noise between antenna elements of a low noise phased array receiver has been carried out. Results of the noise wave analysis, based on fundamental principles of noisy networks, suggest that the coupled noise contribution to system noise temperatures should be smaller than had previously been suggested for systems like the SKA. The principles are applicable to any phased array receiver. Finally, a multi-band antenna has been designed and fabricated for a severe operating environment, covering the three extremely crowded frequency bands, the 2.1 GHz UMTS, the 2.4 GHz ISM and the 5.8 GHz ISM bands. Measurements have demonstrated excellent performance, exceeding that of equivalent commercial antennas aimed at similar applications.

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Labib, Ashraf Adel A. "An investigation into the causal indicators and associated critical parameters for effective quality management in first generation Egyptian ports exemplified by the port of Alexandria." Thesis, University of the West of England, Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407317.

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Marine ports are affected by fast technological development and strong competition as much as any other type tOf organisation. Changes due to the high demand for their services, and increasing customer awareness are imposing demands on their efficiency, effectiveness and ability to provide a high quality service. A few ports have been interested in adopting Total Quality Management (TQM), in order to meet these challenges and have gained benefits from adopting TQM. Most of the marine ports, which have adopted TQM, are European. TQM is unknown to most organisations in developing countries, and it was considered important to investigate how TQM could affect the performance of a developing country's marine ports. This study focused on Total Quality Management exemplified by the EFQM Excellence' Model and set out to examme the possibility of applying it in one of the African countries, namely Egypt. The port of Alexandria was adopted as a case study, in order to, first, investigate the reasons behind its low profitability and high service costs, and second, to investigate the possibility of applying the Excellence Model (as an internationally recognised lnodel of TQM) and investigate its limitations and benefits. Although most of the TQM activities were quite far from the Egyptian public sector culture, the results of this study suggested that it is successfully feasible to adopt the Excellence Model within the existing culture of Alexandria port. It was found that the key issue for ensuring the successful implementation of Business Excellence in Alexandria marine port is to fulfil the requirements of the staff within the organisation given a high respect to govermnent bureaucracy and inflexibility rules. Furthermore the research indicates that there were several methods to solve the limitations which lnay inhibit the successful implementation in Egyptian culture. The most efficient method 'was to gain the commitment of the Egyptian senior managers. Various methods were used in this researc:h for data collection including, unstructured interviews, structured interviews, questionnaire survey and workshop. Furthermore different statistical me:thods were used for ensuring the goodness and the reliability of the data. The findings of this research demonstrated that using Business Excellence criteria (in the light of the results that emerged from the study of the current organisation culture) will improve Alexandria port's performance and enhance its market share.

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CORNEJO, GIANN CARLO. "FEEDBACK CONTROL DESIGN USING TEMPLATE BOUNDARIES FOUND THROUGH A PRUNING ALGORITHM FOR PLANTS WITH PARAMETRIC UNCERTAINTY." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1069447568.

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36

Sieklicki, Michelli de Fatima. "Estudo de genética de população e endogamia em animais da raça Holandesa no estado do Paraná." Universidade Estadual de Ponta Grossa, 2018. http://tede2.uepg.br/jspui/handle/prefix/2477.

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Submitted by Eunice Novais (enovais@uepg.br) on 2018-04-25T18:05:26Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Michelli Sieklicki.pdf: 1236462 bytes, checksum: de51a11749361af8058466a0d8ddcb71 (MD5)
Made available in DSpace on 2018-04-25T18:05:26Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Michelli Sieklicki.pdf: 1236462 bytes, checksum: de51a11749361af8058466a0d8ddcb71 (MD5) Previous issue date: 2018-03-05
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O objetivo deste estudo foi avaliar a estrutura populacional e endogâmica dos rebanhos da raça Holandesa no estado do Paraná, a fim de verificar o processo de distribuição dos genes entre os animais ao longo dos anos. Os dados utilizados foram fornecidos pela Associação Paranaense dos Criadores da Raça Holandesa – APCBRH, com arquivo de pedigree de 206.796 animais, nascidos entre 1970 a 2014. Foram obtidos resultados para integridade do pedigree, pedigree completo, número efetivo de fundadores (fe) e número efetivo de ancestrais (fa), intervalo de gerações (IG), coeficiente de endogamia (F), tamanho efetivo de população (Ne), coeficiente médio de relação (CR) e número de progênies por reprodutor. Para o cálculo dos parâmetros populacionais e endogamia foram utilizados os softwares POPREP e ENDOG v.4.5. Com base no conjunto de dados, o pedigree completo apresentou animais com parentesco conhecido até a sexta geração. O intervalo de geração médio na população foi de 6,3 anos. Para o coeficiente médio de endogamia o resultado foi de 4,99%. Ne variou durante os períodos, variando de 22 a 114, enquanto a taxa de endogamia existente nestes mesmos períodos mostrou uma tendência decrescente nos últimos anos até 2014. Para o resultado de CR foi estimado em 0,71%. O número efetivo de fundadores (fe) foi de 418 animais e ancestrais (fa) foram 400 animais. Adicionalmente, foram identificados os reprodutores com maior número de progênies na população. De acordo com o nível de endogamia apresentado, pôde-se observar que disseminação do material genético dos principais reprodutores entre as gerações, resultou em bons indicadores de diversidade genética, o que permitiu propiciar uma boa estruturação genética dos rebanhos, facilitando a condução dos programas de seleção genética da raça, no referido estado.
The objective of the present study was to evaluate the population structure and inbreeding of Holstein herds in the state of Paraná. The data used were provided by the Holstein Association of Paraná (APCBRH), which included a pedigree file of 206,796 animals born between 1970 and 2014. Results were obtained pertaining to pedigree integrity, complete pedigree, effective number of founders (f) and effective number of ancestors (fa), generation interval (GI), inbreeding coefficient (F), size effective population (Ne), mean ratio coefficient (CR), and number of progenies per breeder. The POPREP and ENDOG v.4.5 software were used to calculate the relevant population parameters and inbreeding. Based on the data set, the pedigree completeness presented animals with known relationship up to a sixth generation. The mean generation interval in the population was 6.3 years. For the average inbreeding coefficient, the result was 4.99%. Ne varied during the periods, ranging from 22 to 114, while the rate of inbreeding in these same periods showed a decreasing trend in the last years until 2014. The CR was estimated to be 0.71%. The effective number of founders (fe) was 418 animals and ancestors (fa) were 400 animals. In addition, the reproducers with the highest number of progenies in the population were identified. According to the level of inbreeding presented, it was observed that the dissemination of the genetic material of the main breeders between the generations, resulted in good indicators of genetic diversity, which allowed to propitiate a good genetic structuring of the herds, facilitating the conduction of the breeding programs genetic selection of the breed in the said state.

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BERNARD, KIVUMBI. "EVALUATION OF POSSIBLE GASIFIER-ENGINE APPLICATIONS WITH MUNICIPAL SOLID WASTE (A CASE STUDY OF KAMPALA)." Thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98777.

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Gasification of biomass for electricity power generation has been a proven technology in a number of countries in the world. MSW consists of biomass, glass, plastics, metallic scrap and street debris. Biomass constitutes the highest proportion of MSW and being an energy resource, implies that it can contribute tremendously to the energy needs of any country since every country is endowed with this resource which is generated in enormous tonnes per day. The challenge would then be the choice of the technology to harness this abundant energy resource subject to financial and environmental constraints. In Uganda, MSW gasification for power generation has never been implemented in spite of the 500-600 tonnes of MSW collected per day, the biomass component of the MSW comprising 88%. MSW is instead collected in skips, transported by trucks to a landfill were it is deposited and left to decompose releasing methane (CH4) and carbon dioxide (CO2) gases which are highly potent greenhouse gases. In this regard, the many tonnes per day of MSW collected in Kampala city (area of the study) portray significant potential of generating producer gas using the technology of gasification to run engines for power generation and this study evaluated possible gasifier-engine system applications for power generation. Experiments were carried out at the Faculty of Technology, Makerere University to determine biomass characteristics (e.g. moisture content, ash content) and gasification parameters(e.g. lower heating value) of MSW required for gasifier-engine applications. After establishing the lower heating value of the producer gas from MSW, a theoretical design of a gasifier-engine system was investigated for possible applications with the biomass component of MSW and an economic analysis was done to assess the feasibility of the project.

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Schulze, H. Georg. "The central administration of oxytocin and oxytocin analogs to steroid-primed female rats : an investigation of the effects of brain site, dose, receptor type, and time parameters on the generation of lordosis behavior." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/31479.

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Oxytocin plays an important role in the orchestration of many behaviors, including reproductive behaviors, in the female rat. Although it is known to influence sexual receptivity, relatively little is known about the central sites of action of oxytocin and how these contribute to the generation of lordosis. Furthermore, it is not clear what the mechanisms of action of this peptide at these sites may be, and how temporal factors influence oxytocinergic activity. The purpose of this thesis is to investigate the role of oxytocin in the generation of lordosis behavior in the female rat from a variety of perspectives in order to gain a broader understanding of this behavior. The administration of low doses of oxytocin to the lateral ventricle of female rats treated with 5 µg estradiol benzoate and 150 µg progesterone inhibited lordosis behavior while higher doses had no effect. This contrasted with the administration of similar oxytocin doses to the medial preoptic area where low doses had little effect and higher doses tended to elevate primarily lordosis quotients. Higher oxytocin doses administered to the ventromedial hypothalamus extended lordosis durations but had a smaller effect on lordosis quotients. In the central nucleus of the amygdala, the same high doses also extended lordosis durations but not lordosis quotients. These results imply that different brain sites may contribute to different aspects of the lordosis behavior: the medial preoptic area appears to be responsible for lordosis frequency (as measured by the lordosis quotient), the amygdala for lordosis duration, and the hypothalamus perhaps for lordosis initiation. The infusion of an oxytocin agonist and antagonist into the lateral ventricles of steroid-primed female rats reduced lordosis quotients. The same agents infused into the medial preoptic area and the ventromedial hypothalamus did not produce any significant effects. These results are difficult to interpret but appear to be congruent with the notion that both the vasopressinergic system and the oxytocinergic system exercise control over lordosis behavior. The former system is inhibitory while the latter system appears to facilitate sexual behavior only when a certain threshold of neural activity has been reached. It furthermore appears likely that both peptides can act on the receptors of both systems. When infused into the left lateral ventricles of steroid-treated female rats, the oxytocin agonist employed in these studies facilitated lordosis behavior 32 h after estradiol administration but not 48 h later when most reported investigations have been carried out. This implies that sufficient' functional oxytocin receptors are induced within 32 h after estrogen treatment. It also raises the possibility that receptor induction and decay at different central sites may follow different time courses. Taken together, these studies indicate that several brain sites contribute to the generation of lordosis and that both the vasopressinergic and oxytocinergic systems may be involved. Furthermore, these systems may be differentiated by temporal patterns of activation.
Arts, Faculty of
Psychology, Department of
Graduate

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39

Wintergerst, Eike [Verfasser], and A. [Akademischer Betreuer] Albers. "Leitfaden zur deduktiven Gestaltvariation durch Ermittlung der funktionsbestimmenden Stellgrößen in der Produktgenerationsentwicklung = Guideline for deductive design variation by determination of the relevant parameters in product generation development [[Elektronische Ressource]] / Eike Wintergerst. Betreuer: A. Albers." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1074463684/34.

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40

Hörmann, Wolfgang, and Josef Leydold. "Generating Generalized Inverse Gaussian Random Variates." WU Vienna University of Economics and Business, 2013. http://epub.wu.ac.at/3784/1/Report123.pdf.

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The generalized inverse Gaussian distribution has become quite popular in financial engineering. The most popular random variate generator is due to Dagpunar (1989). It is an acceptance-rejection algorithm method based on the Ratio-of-uniforms method. However, it is not uniformly fast as it has a prohibitive large rejection constant when the distribution is close to the gamma distribution. Recently some papers have discussed universal methods that are suitable for this distribution. However, these methods require an expensive setup and are therefore not suitable for the varying parameter case which occurs in, e.g., Gibbs sampling. In this paper we analyze the performance of Dagpunar's algorithm and combine it with a new rejection method which ensures a uniformly fast generator. As its setup is rather short it is in particular suitable for the varying parameter case. (authors' abstract)
Series: Research Report Series / Department of Statistics and Mathematics

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41

Knápek, Michal. "Posouzení výhodnosti výstavby přečerpávací vodní elektrárny velkého výkonu v lokalitě Cukrová bouda, okres Šumperk." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219416.

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The subject matter of the master´s thesis is, in particular, an evaluation of the advantageousness of the construction of a pumped-storage hydroelectric power station in the vicinity of Cukrová Bouda. In the master´s thesis introduction the utilisation of pumped-storage hydroelectric power stations in providing reserve power generation to the operator of a power transmission system is discussed. The thesis then focuses on a technical design solution where two alternatives are drawn up for which the nominal parameters of individual designs for a pumped-storage hydroelectric power station are specified. The following part deals with the impact of the structure and the plant’s subsequent operation on the environment. A further key part is the determination of investment and subsequent operating costs and an evaluation of the plant according to economic pointers. The final part of the master´s thesis contains a SWOT analysis and an assumed programme of works for the plant’s preparation and actual construction. The conclusion contains an overall evaluation.

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Siddiqui, Asher. "Capturing JUnit Behavior into Static Programs : Static Testing Framework." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-5510.

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In this research paper, it evaluates the benefits achievable from static testing framework by analyzing and transforming the JUnit3.8 source code and static execution of transformed code. Static structure enables us to analyze the code statically during creation and execution of test cases. The concept of research is by now well established in static analysis and testing development. The research approach is also increasingly affecting the static testing process and such research oriented work has proved particularly valuable for those of us who want to understand the reflective behavior of JUnit3.8 Framework.

JUnit3.8 Framework uses Java Reflection API to invoke core functionality (test cases creation and execution) dynamically. However, Java Reflection API allows developers to access and modify structure and behavior of a program. Reflection provides flexible solution for creating test cases and controlling the execution of test cases. Java reflection helps to encapsulate test cases in a single object representing the test suite. It also helps to associate each test method with a test object. Where reflection is a powerful tool to perform potential operations, on the other hand, it limits static analysis. Static analysis tools often cannot work effectively with reflection.

In order to avoid the reflection, Static Testing Framework provides a static platform to analyze the JUnit3.8 source code and transform it into non-reflective version that emulates the dynamic behavior of JUnit3.8. The transformed source code has possible leverage to replace reflection with static code and does same things in an execution environment of Static Testing Framework that reflection does in JUnit3.8. More besides, the transformed code also enables execution environment of Static Testing Framework to run test methods statically. In order to measure the degree of efficiency, the implemented tool is evaluated. The evaluation of Static Testing Framework draws results for different Java projects and these statistical data is compared with JUnit3.8 results to measure the effectiveness of Static Testing Framework. As a result of evaluation, STF can be used for static creation and execution of test cases up to JUnit3.8 where test cases are not creating within a test class and where real definition of constructors is not required. These problems can be dealt as future work by introducing a middle layer to execute test fixtures for each test method and by generating test classes as per real definition of constructors.

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43

Fenollosa, Artés Felip. "Contribució a l'estudi de la impressió 3D per a la fabricació de models per facilitar l'assaig d'operacions quirúrgiques de tumors." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667421.

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La present tesi doctoral s’ha centrat en el repte d’aconseguir, mitjançant Fabricació Additiva (FA), models per a assaig quirúrgic, sota la premissa que els equips per fer-los haurien de ser accessibles a l’àmbit hospitalari. L’objectiu és facilitar l’extensió de l’ús dels prototips com a eina de preparació d’operacions quirúrgiques, transformant la pràctica mèdica actual de la mateixa manera que en el seu moment ho van fer tecnologies com les que van facilitar l’ús de radiografies. El motiu d’utilitzar FA, en lloc de tecnologies més tradicionals, és la seva capacitat de materialitzar de forma directa les dades digitals obtingudes de l’anatomia del pacient mitjançant sistemes d’escanejat tridimensional, fent possible l’obtenció de models personalitzats. Els resultats es centren en la generació de nou coneixement sobre com aconseguir equipaments d’impressió 3D multimaterials accessibles que permetin l’obtenció de models mimètics respecte als teixits vius. Per facilitar aquesta buscada extensió de la tecnologia, s’ha focalitzat en les tecnologies de codi obert com la Fabricació per Filament Fos (FFF) i similars basades en líquids catalitzables. La recerca s’alinea dins l’activitat de desenvolupament de la FA al CIM UPC, i en aquest àmbit concret amb la col·laboració amb l’Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloc de la tesi inclou la descripció de l’estat de l’art, detallant les tecnologies existents i la seva aplicació a l’entorn mèdic. S’han establert per primer cop unes bases de caracterització dels teixits vius -sobretot tous- per donar suport a la selecció de materials que els puguin mimetitzar en un procés de FA, a efectes de millorar l’experiència d’assaig dels cirurgians. El caràcter rígid dels materials majoritàriament usats en impressió 3D els fa poc útils per simular tumors i altres referències anatòmiques. De forma successiva, es tracten paràmetres com la densitat, la viscoelasticitat, la caracterització dels materials tous a la indústria, l’estudi del mòdul elàstic de teixits tous i vasos, la duresa d’aquests, i requeriments com l’esterilització dels models. El segon bloc comença explorant la impressió 3D mitjançant FFF. Es classifiquen les variants del procés des del punt de vista de la multimaterialitat, essencial per fer models d’assaig quirúrgic, diferenciant entre solucions multibroquet i de barreja al capçal. S’ha inclòs l’estudi de materials (filaments i líquids) que serien més útils per mimetitzar teixits tous. Es constata com en els líquids, en comparació amb els filaments, la complexitat del treball en processos de FA és més elevada, i es determinen formes d’imprimir materials molt tous. Per acabar, s’exposen sis casos reals de col·laboració amb l’HJSD, una selecció d’aquells en els que el doctorand ha intervingut en els darrers anys. L’origen es troba en la dificultat de l’abordatge d’operacions de resecció de tumors infantils com el neuroblastoma, i a la iniciativa del Dr. Lucas Krauel. Finalment, el Bloc 3 té per objecte explorar nombrosos conceptes (fins a 8), activitat completada al llarg dels darrers cinc anys amb el suport dels mitjans del CIM UPC i de l’activitat associada a treballs finals d’estudis d’estudiants de la UPC, arribant-se a materialitzar equipaments experimentals per validar-los. La recerca ampla i sistemàtica al respecte fa que s’estigui més a prop de disposar d’una solució d’impressió 3D multimaterial de sobretaula. Es determina que la millor via de progrés és la de disposar d’una pluralitat de capçals independents a fi de capacitar la impressora 3D per integrar diversos conceptes estudiats, materialitzant-se una possible solució. Cloent la tesi, es planteja com seria un equipament d’impressió 3D per a models d’assaig quirúrgic, a fi de servir de base per a futurs desenvolupaments.
La presente tesis doctoral se ha centrado en el reto de conseguir, mediante Fabricación Aditiva (FA), modelos para ensayo quirúrgico, bajo la premisa que los equipos para obtenerlos tendrían que ser accesibles al ámbito hospitalario. El objetivo es facilitar la extensión del uso de modelos como herramienta de preparación de operaciones quirúrgicas, transformando la práctica médica actual de la misma manera que, en su momento, lo hicieron tecnologías como las que facilitaron el uso de radiografías. El motivo de utilizar FA, en lugar de tecnologías más tradicionales, es su capacidad de materializar de forma directa los datos digitales obtenidos de la anatomía del paciente mediante sistemas de escaneado tridimensional, haciendo posible la obtención de modelos personalizados. Los resultados se centran en la generación de nuevo conocimiento para conseguir equipamientos de impresión 3D multimateriales accesibles que permitan la obtención de modelos miméticos respecto a los tejidos vivos. Para facilitar la buscada extensión de la tecnología, se ha focalizado en las tecnologías de código abierto como la Fabricación por Hilo Fundido (FFF) y similares basadas en líquidos catalizables. Esta investigación se alinea dentro de la actividad de desarrollo de la FA en el CIM UPC, y en este ámbito concreto con la colaboración con el Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloque de la tesis incluye la descripción del estado del arte, detallando las tecnologías existentes y su aplicación al entorno médico. Se han establecido por primera vez unas bases de caracterización de los tejidos vivos – principalmente blandos – para dar apoyo a la selección de materiales que los puedan mimetizar en un proceso de FA, a efectos de mejorar la experiencia de ensayo de los cirujanos. El carácter rígido de los materiales mayoritariamente usados en impresión 3D los hace poco útiles para simular tumores y otras referencias anatómicas. De forma sucesiva, se tratan parámetros como la densidad, la viscoelasticidad, la caracterización de materiales blandos en la industria, el estudio del módulo elástico de tejidos blandos y vasos, la dureza de los mismos, y requerimientos como la esterilización de los modelos. El segundo bloque empieza explorando la impresión 3D mediante FFF. Se clasifican las variantes del proceso desde el punto de vista de la multimaterialidad, esencial para hacer modelos de ensayo quirúrgico, diferenciando entre soluciones multiboquilla y de mezcla en el cabezal. Se ha incluido el estudio de materiales (filamentos y líquidos) que serían más útiles para mimetizar tejidos blandos. Se constata como en los líquidos, en comparación con los filamentos, la complejidad del trabajo en procesos de FA es más elevada, y se determinan formas de imprimir materiales muy blandos. Para acabar, se exponen seis casos reales de colaboración con el HJSD, una selección de aquellos en los que el doctorando ha intervenido en los últimos años. El origen se encuentra en la dificultad del abordaje de operaciones de resección de tumores infantiles como el neuroblastoma, y en la iniciativa del Dr. Lucas Krauel. Finalmente, el Bloque 3 desarrolla numerosos conceptos (hasta 8), actividad completada a lo largo de los últimos cinco años con el apoyo de los medios del CIM UPC y de la actividad asociada a trabajos finales de estudios de estudiantes de la UPC, llegándose a materializar equipamientos experimentales para validarlos. La investigación amplia y sistemática al respecto hace que se esté más cerca de disponer de una solución de impresión 3D multimaterial de sobremesa. Se determina que la mejor vía de progreso es la de disponer de una pluralidad de cabezales independientes, a fin de capacitar la impresora 3D para integrar diversos conceptos estudiados, materializándose una posible solución. Para cerrar la tesis, se plantea cómo sería un equipamiento de impresión 3D para modelos de ensayo quirúrgico, a fin de servir de base para futuros desarrollos.

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44

Fujdiak, Radek. "Analýza a optimalizace datové komunikace pro telemetrické systémy v energetice." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-358408.

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Telemetry system, Optimisation, Sensoric networks, Smart Grid, Internet of Things, Sensors, Information security, Cryptography, Cryptography algorithms, Cryptosystem, Confidentiality, Integrity, Authentication, Data freshness, Non-Repudiation.

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45

Su, Hung-Yu, and 蘇弘毓. "A Study of User Authentication and Cryptographic key Generation Based on Keystroke Dynamics." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/85880660164600500011.

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碩士
國立成功大學
資訊工程學系碩博士班
91
The biometrics is to make use of in each living creature individual, can represent that individual, and make use of the not same characteristic in other individual. Reach the function that recognize. Such as fingerprint, iris, sound… etc. And in the computer systems, distinguish the user’s different, only have depend on whether ID and passwords form couples or not to decide. With time passed, intruders also develop lots of way or guessing passwords, to get data or personal privacy originally store in system. Enhancing the password systems. It also with the user''s keystroke dynamics at many researches Proved the user''s keystroke is a repeatable occurrence. And adding user''s keystroke dynamics in password system can use the minimum cost to get the biggest benefit. Besides, in addition to user recognizing, we make use of keystroke dynamics and its property of repeatable to record private key of the user. Only the user input his ID and password, system can restore the key that is not stored in the systems. Then provided for other uses, such as using the public key systems, signature ... etc.

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46

Truong, Phat M. "Investigation of synchronous generator parameters for integrated HVDC generation." 1989. http://hdl.handle.net/1993/16944.

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47

Mu, Peter, and 穆彼得. "Systematic Generation of Instruction Test Patterns Based on Architectural Parameters." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/54193909595497436312.

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碩士
國立中山大學
資訊工程學系研究所
89
When we survey hardware design groups, we can find that it is now dedicated to verification between 60 to 80 percent. According to the instruction set architecture information should be a feasible and reasonable way for generating the test pattern to verify the function of a microprocessor. In this these, we’ll present an instruction test pattern (for microprocessors) generation method based on the instruction set architecture. It can help the users to generate the instruction test pattern efficiently. The generation flow in this thesis contains three major flows: individual instruction, instruction pair, and manual generation. They are used for different verification cases. The “individual instruction” could be used for verifying the functions of each implemented instructions. The “instruction pair” could be used for verifying the interaction of instruction execution in a pipeline for a HDL implementation of a microprocessor. The “manual generation” could be used to verify some corner cases (behaviors) of the microprocessor. As the quality of our test pattern, we generate some patterns for 32-bits instruction (ARM instruction sets and SPARC instruction sets) and use them to verify a synthesizable RTL core. With some handwriting test pattern (34.7%), our automatic generation method can approach 100% HDL code coverage of the microprocessor design. We use the HDL code coverage as the reference of test pattern quality. Because our generation method is based on the instruction field, we can describe most instruction set for the generator. Hence, our generation method can retarget to most instruction set architecture without modifying the generator. Besides the RISC instructions, even the CISC instructions could be generated.

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48

Nayak, Omprakash B. "Optimization of automatic generation control parameters using a transient stability program." 1990. http://hdl.handle.net/1993/9624.

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49

Dai, Yang. "Parameters influencing generation of cryptic pathogenic T-cell epitopes in thyroglobulin /." 2002.

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50

Nurhadi, Indera. "Investigation of the influence of gear system parameters on noise generation." 1985. http://catalog.hathitrust.org/api/volumes/oclc/12621931.html.

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Thesis (Ph. D.)--University of Wisconsin--Madison, 1985.
Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 199-204).

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