The computational ability to accurately predict the dynamic behavior of a nuclear reactor core in response to reactivity-induced perturbations is an important subject in the field of reactor physics. Space-time and point kinetics methodologies were developed for the purpose of studying the transient-induced behavior of the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor’s (HFIR) compact core. The space-time simulations employed the three-group neutron diffusion equations, which were solved via the COMSOL partial differential equation coefficient application mode. The point kinetics equations were solved with the PARET code and the COMSOL ordinary differential equation application mode. The basic nuclear data were generated by the NEWT and MCNP5 codes and transients initiated by control cylinder and hydraulic tube rabbit ejections were studied. The space-time models developed in this research only consider the neutronics aspect of reactor kinetics, and therefore, do not include fluid flow, heat transfer, or reactivity feedback. The research presented in this dissertation is the first step towards creating a comprehensive multiphysics methodology for studying the dynamic behavior of the HFIR core during reactivity-induced perturbations. The results of this study show that point kinetics is adequate for small perturbations in which the power distribution is assumed to be time-independent, but space-time methods must be utilized to determine localized effects. En route to developing the kinetics methodologies, validation studies and methodology updates were performed to verify the exercise of major neutronic analysis tools at the HFIR. A complex MCNP5 model of HFIR was validated against critical experiment power distribution and effective multiplication factor data. The ALEPH and VESTA depletion tools were validated against post-irradiation uranium isotopic mass spectrographic data for three unique full power cycles. A TRITON model was developed and used to calculate the buildup and reactivity worth of helium-3 in the beryllium reflector, determine whether discharged beryllium reflectors are at transuranic waste limits for disposal purposes, determine whether discharged beryllium reflectors can be reclassified from hazard category 1 waste to category 2 or 3 for transportation and storage purposes, and to calculate the curium target rod nuclide inventory following irradiation in the flux trap.

No description available.

Sorghum (Sorghum bicolor (L). Moench) is used for human consumption in parts of Africa and Asia and as an animal feed mainly in the U.S. Though sorghum grain contains higher amounts of protein than other cereal grains such as wheat and corn, it is not as readily available for enzyme degradation in humans and animals. Protein body matrices called kafirins surround the starch granules in sorghum. Because the protein is less digestible, the starch is also less digestible for biofuel production. However variation for this trait exists and the line P850029 has a higher protein digestibility compared to other normal grain sorghum lines. This increase in digestibility of protein is due to the rearrangement of the kafirins in the prolamin protein bodies where, the γ-kafirins are rearranged in the seed endosperm and the amount of γ-kafirin in the grain is also reduced. The assay to phenotype the HD trait is time consuming and unpredictable. So identifying a quantitative trait loci (QTL) controlling the protein digestibility trait in sorghum would be beneficial in breeding. A recombinant inbred lines (RILs) population derived from P850029 x ‘Sureno’, were developed and used to map QTL regulating the protein digestibility trait. A single QTL was identified on chromosome 1 between Xtxp43 and Xtxp329. Validation of the identified QTL was done on heterogenous inbred families (HIFs). The results validate the same QTL identified on the RIL population on chromosome 1. Later the high digestibility trait (HD) was integrated with the Waxy trait in sorghum. The Waxy (WX) sorghums have starch completely in the form of amylopectin. The effect of endosperm type on ethanol yield and fermentation efficiencies was studied among HD, WX and HD-WX lines. The HD-WX lines fermented in a shorter time i.e. completed fermentation in 48 h and their fermentation efficiencies were also higher around 90%. The DDGS of the HD-WX lines also had lower residual starch content and 50% higher amino acid lysine content when compared to wildtype sorghum. Moreover, the relation between endosperm traits and grain yield in sorghum has not been fully explored. In this study, we compared the yield and yield components of four unique endosperm phenotypes, HD, WX, HD-WX and wildtype lines. A total of 100 F2:4 derived recombinant inbred lines population from a cross between Tx2907/P850029 were selected with 25 lines from each HD, WX, HD-WX and wild-type line were included in the study. These lines were grown in three replications in College Station and Halfway, Texas in a randomized complete block design. The results show that there are no significant differences in the grain yield.

The measurement of trace gases through remote sounding techniques has led to a better understanding of the processes controlling the structure and variability of the stratosphere. Differences between measurements over space and time are due to atmospheric variability and instrument errors: thus, comparison of measurements can be used to test our knowledge of both. Comparisons of measurements over long time periods are used to identify trends. Balloon-borne infrared emission radiometer instruments have been used to make measurements of midlatitude stratospheric HNO3 spanning a period of twelve years. The timing of the measurements is notable, since they occur before and well after the eruption of Mt. Pinatubo, which significantly perturbed HNO3 levels, complicating prior trend analyses. No significant differences are found between the HNO3 retrievals, although large measurement uncertainties preclude any conclusion concerning trends. Comparisons of measurements that are closely spaced in space and time are useful for satellite validation, where one aims to reduce the effect of atmospheric variability on the estimation of systematic and random errors. A novel technique for the estimation of systematic error, which differentiates between additive and multiplicative bias, is introduced. In a comparison of measurements by the ACE-FTS and Aura MLS instruments, significant multiplicative biases are identified and described. In order to validate the reported random errors (RREs) of measurements, satellite validation studies often focus on measurements in the tropical stratosphere, where variability is weak. The scatter in tropical measurements can then be used as an upper limit on instrument precision. In an analysis of tropical measurements by the ACE-FTS, scatter is found to be roughly consistent with the RREs for H2O and CO. The scatter in measurements of O3, HNO3, and N2O, while larger than the reported random errors, is roughly consistent with the variability simulated in the Canadian Middle Atmosphere Model. This work implies that the random error of the ACE-FTS measurements is smaller than the weak natural variability of the tropical stratosphere.

Pre-harvest sprouting (PHS) in bread wheat (<i>Triticum aestivum</i> L.) is one of the major abiotic constraints influencing the production of high quality grain. The flour milled from sprouted wheat grains has increased Ñ-amylase activity as compared to non-sprouted grain. PHS negatively affects the properties of flour with deleterious effects on bread and noodle quality. White-grained wheat is generally more susceptible to PHS damage than red-grained wheat. The objectives of this study were to identify a suitable method for phenotyping PHS resistance and to identify PHS resistance genomic regions and markers that could be used for marker-assisted selection in wheat improvement programs. A doubled haploid (DH) mapping population from a cross between two white-grained spring wheat genotypes, Argent (non-dormant) and W98616 (dormant) was used in this study. Forty DH lines (20 dormant and 20 non-dormant) were evaluated for germination frequency, Falling Number, and Ñ-amylase activity in dry and water-imbibed seeds and spikes. The germination test was the most reliable method for measurement of PHS resistance, whereas the Falling Number and Ñ-amylase activity in dry harvested seeds could not be correlated to dormancy levels. However, a positive association (r = 0.60***) was detected between germination frequency and Ñ-amylase activity in imbibed seeds. To identify the genomic regions associated with PHS resistance, a genetic linkage map with a total genome coverage of 2,577 cM was developed. The map was constructed from 913 scored markers (356 SSR, 290 AFLP, 258 DArT and 9 EST) with an average marker density of 3.7 cM/marker. Five genomic regions on chromosomes 1A, 3A, 4A, 7A and 7D were associated with PHS resistance by interval mapping and all regions were contributed by the dormant parent W98616. A total of 60 Canadian wheat cultivars and experimental lines were screened with three SSR markers, DuPw004, barc170 and wmc650, located under the major quantitative trait locus (QTL) on chromosome 4A. The SSR markers explained 60-75% of the total variation in germination frequency among different wheat genotypes. By using the DuPw004 marker in marker-assisted back crossing, the population size in the BC1F1 and BC2F1 generations were reduced by 41% and 59%, respectively. Thus, the 4A QTL markers have been proven useful for marker-assisted selection of PHS resistance for wheat improvement.

Previous investigations of the Level of Service Inventory Ontario Revision (LSI-OR) have examined individual subgroups of offenders (e.g., women, Aboriginal offenders), which has made comparisons of its predictive validity between specific offender groups suspect. This study was conducted on a complete cohort of 26,450 offenders who were released from Ontario provincial correctional facilities, sentenced to a conditional sentence, or who began a term of probation in 2004. Participants were followed up for at least four years to collect recidivism information on numerous subgroups of offenders including males (81.7%), females (18.3%), Aboriginal (6.4%), Black (7.3%) and Caucasian offenders (59.2%). Analyses revealed that the LSI-OR scores are positively correlated with recidivism (r = .441, p < .001), and similar correlations were found for all offenders regardless of gender or race, (Aboriginal r = .377, p < .001; Black, r = .420, p < .001; Caucasian, r = .417, p < .001; Male, r = .439, p < .001; Female, r = .426, p < .001). LSI-OR scores are also correlated with severity of the recidivism offence, (r = .098, p <.001) indicating that higher LSI-OR scores are related to higher offence severity for all ethnicities, sentence types, and genders. These findings indicate that the LSI-OR is an effective risk assessment tool for use among different ethnicities, sentence types and genders for provincially sentenced offenders in Ontario.

Several recent projects in building science have examined the hygric performance of building materials. Most building materials adsorb from and desorb water vapour to their environments. This phenomenon could be used to help control relative humidity fluctuations in buildings, experienced during periods of moisture production such as cooking, washing or bathing. They could also be used to reduce the need for mechanical ventilation and air conditioning to remove excess moisture. To understand how a building material responds to transient changes in relative humidity, testing is required.<p> This thesis outlines the testing performed on gypsum board, a common wall and ceiling finishing material used inside buildings. The effect of paint coatings on the gypsum boards and heat and mass transfer coefficients of the air passing over the gypsum bed was tested. The data produced from these experiments was used to validate several numerical models through an International Energy Agency/Energy Conservation in Buildings and Community Systems (IEA/ECBCS), Annex 41: Whole Building Heat, Air and Moisture Response. The validated models are important for simulating the process of adsorption and desorption in building materials to predict failure in the building envelope and expected indoor air conditions.<p> A sensitivity analysis is also presented which examines the effects of the sorption isotherm and vapour permeability of the gypsum and paints as well as the heat and mass transfer coefficients the boards are exposed to. The sensitivity range used was determined from the tests performed on the gypsum boards and paints which were also performed during the work of Annex 41.<p> The results of this thesis produced a high quality data which can also be used to validate future numerical models. All information required for validation of future models is available such as dimensions of test section, test conditions, material properties and the experimental data.<p> The results show that when designing for passive humidity control in buildings using gypsum boards, the most influential factor is the type of coating or paint applied to the surface. The sensitivity analysis showed that material properties such as vapour permeability and the sorption isotherms, for the expected temperature range, should be well known for increased accuracy of the simulation. The material properties were determined from inter-laboratory testing at 14 different institutions to achieve confident values.<p> The effect of increasing the heat and mass transfer coefficients, over the range of coefficients studied in this thesis, showed negligible differences in the results. The simulated results had very good agreement between the models and were mostly within experimental uncertainty of the measurements.

This thesis is a study of an indirect heat pump assisted solar domestic hot water (I-HPASDHW) system, where the investigated configuration is called the Dual Side I-HPASDHW system. The study outlines the development of an Experimental Test Unit (ETU), and focuses on the experimental validation of TRNSYS models. Shortcomings of the system design realized throughout the validation process, as well as weaknesses in the control schemes used to operate the system are also provided. A description of the Dual Side I-HPASDHW system is provided along with the design intent of the system. The corresponding ETU is presented in detail to provide a comprehensive understanding of the ETU’s simulation capabilities. Components of the ETU, such as the heat pump, heat exchanger, and domestic hot water (DHW) tank are characterized in order to provide input data for built-in TRNSYS models, and to develop custom TRNSYS models for the heat pump and heat exchanger. Heat exchanger performance is modelled with a linear correlation, while the heat pump performance is mapped by applying experimental data to three-dimensional surface fitting software. For the purpose of validation, the ETU is used to simulate the performance of the Dual Side I-HPASDHW system under a realistic control scheme. Four full day tests are conducted using data from a fall, winter, and summer day. The full day summer test is repeated with and without electrical backup heating. The TRNSYS model of the Dual Side system is tuned in order to provide the closest match possible between the computer simulation and the measured performance of the ETU. Experimental tests were compared with TRNSYS simulations to reveal some disparity in the results. The majority of simulation error was attributed to inaccuracy in modeling DHW tank temperatures and water circulation patterns. The disparity created by the DHW tank model only resulted in substantial performance deviation when inaccurate DHW temperatures were used directly for vital control decisions. Conclusions were drawn suggesting that the TRNSYS model of the ETU was valid for a majority of operating conditions, often matching experimental tests well within experimental uncertainty. Caution was recommended towards the use of the developed TRNSYS model, where techniques were recommended for tracking and minimizing substantial simulation errors. Several key performance issues affecting the Dual Side I-HPASDHW system were targeted with recommendations for design and control alterations, along with future improvement and optimization studies.

The measurement of trace gases through remote sounding techniques has led to a better understanding of the processes controlling the structure and variability of the stratosphere. Differences between measurements over space and time are due to atmospheric variability and instrument errors: thus, comparison of measurements can be used to test our knowledge of both. Comparisons of measurements over long time periods are used to identify trends. Balloon-borne infrared emission radiometer instruments have been used to make measurements of midlatitude stratospheric HNO3 spanning a period of twelve years. The timing of the measurements is notable, since they occur before and well after the eruption of Mt. Pinatubo, which significantly perturbed HNO3 levels, complicating prior trend analyses. No significant differences are found between the HNO3 retrievals, although large measurement uncertainties preclude any conclusion concerning trends. Comparisons of measurements that are closely spaced in space and time are useful for satellite validation, where one aims to reduce the effect of atmospheric variability on the estimation of systematic and random errors. A novel technique for the estimation of systematic error, which differentiates between additive and multiplicative bias, is introduced. In a comparison of measurements by the ACE-FTS and Aura MLS instruments, significant multiplicative biases are identified and described. In order to validate the reported random errors (RREs) of measurements, satellite validation studies often focus on measurements in the tropical stratosphere, where variability is weak. The scatter in tropical measurements can then be used as an upper limit on instrument precision. In an analysis of tropical measurements by the ACE-FTS, scatter is found to be roughly consistent with the RREs for H2O and CO. The scatter in measurements of O3, HNO3, and N2O, while larger than the reported random errors, is roughly consistent with the variability simulated in the Canadian Middle Atmosphere Model. This work implies that the random error of the ACE-FTS measurements is smaller than the weak natural variability of the tropical stratosphere.

Per tal de garantir la qualitat final d'un sistema d'informació, és imprescindible que l'esquema conceptual que representa el coneixement sobre el seu domini i les funcions que ha de realitzar sigui semànticament correcte.La correctesa d'un esquema conceptual es pot veure des de dues perspectives. Per una banda, des del punt de vista de la seva definició, determinar la correctesa d'un esquema conceptual consisteix en respondre la pregunta "És correcte l'esquema conceptual?". Aquesta pregunta es pot respondre determinant si l'esquema satisfà certes propietats, com satisfactibilitat, no redundància o executabilitat de les seves operacions.D'altra banda, des de la perspectiva dels requisits que el sistema d'informació ha de satisfer, l'esquema conceptual no només ha de ser correcte sinó que també ha de ser el correcte. Per tal d'assegurar-ho, el dissenyador necessita algun tipus de guia i ajut durant el procés de validació, de manera que pugui entendre què està representant l'esquema exactament i veure si es correspon amb els requisits que s'han de formalitzar.En aquesta tesi presentem una aproximació que millora els resultats de les propostes anteriors adreçades a validar un esquema conceptual en UML, amb les restriccions i operacions formalitzades en OCL. La nostra aproximació permet validar un esquema conceptual tant des del punt de vista de la seva definició com de la seva correspondència amb els requisits.La validació es porta a terme mitjançant un conjunt de proves que s'apliquen a l'esquema, algunes de les quals es generen automàticament mentre que d'altres són definides ad-hoc pel dissenyador. Totes les proves estan formalitzades de tal manera que es poden tractar d'una manera uniforme,independentment de la propietat específica que determinen.La nostra proposta es pot aplicar tant a un esquema conceptual complet com només a la seva part estructural. Quan es pretén validar només la part estructural d'un esquema, oferim un conjunt de condicions que permeten determinar si qualsevol prova de validació que es pugui fer sobrel'esquema acabarà en temps finit. Per aquells casos en els quals aquestes condicions de terminació se satisfan, també proposem un procediment de raonament sobre l'esquema que s'aprofita d'aquest fet i és més eficient que en el cas general. Aquesta aproximació permet validar esquemes conceptuals molt expressius, assegurant completesa i decidibilitat al mateix temps.Per provar la factibilitat de la nostra aproximació, hem implementat el procés de validació complet per a la part estructural d'un esquema. A més, per a la validació d'un esquema conceptual que inclou la definició del comportament, hem implementat el procediment de raonament estenent un mètode existent. / To ensure the quality of an information system, it is essential that the conceptual schema that represents the knowledge about its domain and the functions it has to perform is semantically correct.The correctness of a conceptual schema can be seen from two different perspectives. On the one hand, from the point of view of its definition, determining the correctness of a conceptual schema consists in answering to the question "Is the conceptual schema right?". This can be achieved by determining whether the schema fulfills certain properties, such as satisfiability, non-redundancy or operation executability.On the other hand, from the perspective of the requirements that the information system should satisfy, not only the conceptual schema must be right, but it also must be the right one. To ensure this, the designer must be provided with some kind of help and guidance during the validation process, so that he is able to understand the exact meaning of the schema and see whether it corresponds to the requirements to be formalized.In this thesis we provide an approach which improves the results of previous proposals that address the validation of a UML conceptual schema, with its constraints and operations formalized in OCL. Our approach allows to validate the conceptual schema both from the point of view of its definition and of its correspondence to the requirements.The validation is performed by means of a set of tests that are applied to the schema, including automatically generated tests and ad-hoc tests defined by the designer. All the validation tests are formalized in such a way that they can be treated uniformly, regardless the specific property they allow to test.Our approach can be either applied to a complete conceptual schema or only to its structural part. In case that only the structural part is validated, we provide a set of conditions to determine whether any validation test performed on the schema will terminate. For those cases in which these conditions of termination are satisfied, we also provide a reasoning procedure that takes advantage of this situation and works more efficiently than in the general case. This approach allows the validation of very expressive schemas and ensures completeness and decidability at the same time. To show the feasibility of our approach, we have implemented the complete validation process for the structural part of a conceptual schema.Additionally, for the validation of a conceptual schema with a behavioral part, the reasoning procedure has been implemented as an extension of an existing method.