Thesis--University of Michigan Law School. / At head of title: Legislative Research Center, the University of Michigan Law School. Includes bibliographical references.

Author's Habilitationsschrift--Universität-Gesamthochschule-Siegen. / Includes bibliographical references (p. 231-247) and index.

No description available.

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: In the present study, two-phase natural circulation flow in a multi-parallel channel system was investigated using experimental and numerical modelling. The investigation was carried out under different power excitations and various system operations (open system, closed system and heat pipe mode). The multichannel system was equipped at the upper end with a condenser enclosed within a steam drum, while the lower portion of each channel was heated to heat the system. For the numerical modelling, transient one-dimensional conservation equations were derived from first principle for both single- and two-phase fluids and used to computer program the system’s discretised simulation model. Temperatures and mass flow rates of the fluid responses as a result of different power excitations and operations were obtained for both the experimental and numerical modelling. It was observed from the results that the fluid experiences a start-up transient before accomplishing steady-state conditions. It was further noted that the transient duration varies with power excitations and system operation modes and hence with the stability of the system. A rise in power proved not to necessarily increase the fluid mass flow rate, but invited oscillations with higher amplitudes, depending on the system’s mode of operation. Type I instability and low-quality steam oscillations were witnessed at low power and open system operation mode (system open to the atmosphere). Type II instabilities and flashing instability were observed to be associated with medium and high-power excitations for the open system mode of operation. The fluid flow became more stable and less oscillatory at all power excitations for the closed system operation mode (system not open to the atmosphere). However, a sub-cooling effect was evident at higher power, where the two-phase fluid temperatures oscillated in a sinusoidal manner. However, the mass flow rates oscillated with high amplitudes in the forward direction in some channels and assumed a unidirectional flow in other channels. In general, steady-state conditions were obtained earlier when the system was operated as a closed system. For the heat pipe mode of operation, the system transient response in all channels exhibited a geysering instability followed by flashing-induced boiling. In-phase (flow in channels exhibiting the same behaviour) and out-of-phase (flow in channels exhibiting contradictory conduct) behaviour between adjacent channels were observed at all power excitations and system operation modes. Flow reversal in heated channels of a natural circulation system were proven to exists even under equal power excitations. / AFRIKAANSE OPSOMMING: In hierdie studie is tweefasige natuurlike sirkulasievloei in ’n parallelle multikanaalstelsel ondersoek deur middel van eksperimentele en numeriese modellering. Die ondersoek is onder verskillende kragopwekkings en verskeie stelselwerkings (oop stelsel, toe stelsel en hittepypmodus). Die multikanaalstelsel is aan die bopunt met ’n kondensor binne ’n stoomdrom toegerus, terwyl die laer gedeelte van elke kanaal verhit is om die stelsel te verhit. Vir die numeriese modellering, is oorgangseendimensionele behoundsvergelykings vanaf die eerste beginsel vir beide een- en tweefasige vloeistowwe afgelei en dit is gebruik om die stelsel se gediskretiseerde simulasiemodel vir ’n rekenaar te programmeer. Temperature en massavloeitempo’s van die vloeistofrespons as gevolg van verskillende kragopwekkings en -werkings is vir beide die eksperimentele en die numeriese modellering verkry. Dit is in die resultate waargeneem dat die vloeistof ’n aansitoorgang ervaar voor dit vloeiewewigstoestande bereik. Daar is verder waargeneem dat die duur van die oorgang wissel volgens kragopwekkings en stelselwerkingsmodusse en dus op grond van die stabiliteit van die stelsel. ’n Toename in krag het nie noodwendig die vloeitempo van die vloeistofmassa verhoog nie, maar het aanleiding gegee tot ossillasies met groter amplitudes, afhangende van die stelsel se metode van werking. Tipe I-onstabiliteit en stoom-ossillasies van ’n lae intensiteit is teen lae krag en oop stelselwerkingsmodus waargeneem (stelsel oop aan die atmosfeer). Tipe II-onstabiliteit en flitsingsonstabiliteit (flashing instability) is met medium- en hoë kragopwekkings vir die oop stelsel modus van werking waargeneem. Die vloeistofvloei het meer stabiel en minder ossillerend geraak by alle kragopwekkings in die geslote stelsel van werking (stelsel nie oop na die atmosfeer nie). ’n Subverkoelingseffek was egter teen hoër krag duidelik, waar die tweefasige vloeistof se temperature sinusvormig geossilleer het. Die massavloeitempo’s het egter met hoë amplitudes in die vorentoe rigting in sommige kanale gevloei en eenrigtingvloei in ander kanale vertoon. Oor die algemeen is vloei-ewewigstoestande vroeër verkry toe die stelsel as ’n geslote stelsel bedryf is. Vir die hittepypmodus van werking het die stelsel se oorgangsweergawe in alle kanale ’n geysering onstabiliteit getoon, gevolg deur flitsinggeïnduseerde (flashing induced) kook. Gelykfasige gedrag (vloei in kanale vertoon dieselfde gedrag) en ongelykfasige gedrag (vloei in kanale vertoon teenstrydige gedrag) tussen langsliggende kanale is met al die kragopwekkings en stelselwerkingsmodusse waargeneem. Vloei-omkering in die verhitte kanale van ’n natuurlike sirkulasiestelsel is bewys om selfs onder gelyke kragopwekkings te bestaan.

The research in this thesis is the first of its kind to describe in a significant level of detail the actual police interviewing of serious crime suspects, with a specific focus on who is being interviewed. The principal information source was 407 real-life audio-tape recordings of interviews with 56 different suspects. Suspects were interviewed for offences that included murder (and attempted murder), sexual assault and serious assault. Tape recordings were obtained from 11 Police Services across England and Wales and were analysed using a specially designed coding frame that captured a range of interviewer and suspect behaviour. The research described how suspects respond during police interviews and examined the interactions between suspect response, interviewer behaviour and case characteristics. Finally, the research assessed the presence and contribution of legal advisors, Appropriate Adults and interpreters. Based on this novel research, the thesis brings out some key findings, highlights where the work is limited and where further exploration is needed, and suggests where interviewing practice might be strengthened. This research is intended to be of interest and practical value to both the research community and the police service.

The Curriculum Assessment Policy Statement (CAPS) for all approved subjects is the result of changes brought to the curriculum that was introduced in 1997. The review of the previous curricula has resulted in the National Curriculum Statement for Grade R-12. The changes in the curriculum were inspired by the Constitution of South Africa (Act 108 of 1996) which aims to “heal the divisions of the past and establish a society based on democratic values, social justice and fundamental human rights” (DBE, 2011a, p. 1). The curriculum aims to ensure that children acquire and apply knowledge and skills in ways that are meaningful to their own lives. The National Curriculum Statement for Physical Sciences aimed to produce learners that are able to “Identify and solve problems and make decisions using critical and creative thinking; collect, analyse, organise and critically evaluate information and use science and technology effectively and critically showing responsibilities towards the environment and the health of others” (DBE, 2011a, p. 8). The aim of this study was to investigate the implementation of CAPS in the Physical Sciences in Grade 10 with particular emphasis on the use of practical work. Two secondary schools, both former Model C schools were used as research sites. Two Physical Sciences teachers and their respective learners participated. The research method used was a case study. The instrument used to collect data was an interview schedule and an observation schedule. Two teachers were interviewed using an interview schedule which consisted of open and closed ended questions. Classroom observation of the practical lessons was conducted with an observation schedule. The data obtained through these instruments was analysed using an interpretive approach. The findings of the research reveal that one school in the sample was not adequately resourced to conduct practical work. The outcome of this study would enable education officials to have an insight of challenges (e.g. lack of resources, larges class sizes, etc.), that are experienced by teachers in respect of the implementation of practical work in schools.

This study is an action research project where I study my own practice in giving feedback in investigative tasks. The aim is to find ways of improving my feedback by engaging learners in conversation and eliciting misconceptions. The study is framed by a sociocultural view of learning and teaching. The study was conducted in a high school with a class of Grade 10 learners who worked on an investigative task and six lessons were video recorded. Analysis was based on the investigative task, feedback given to learners, misconceptions that arose and conversations that took place during the lessons. The findings are that when developing an investigative task, the teacher should look for mathematical processes that can be developed as learners work on it. I found that I both took up and missed opportunities to work with learners’ misconceptions and that four components of mathematical conversations: questioning, explaining mathematical ideas, sources of mathematical ideas and responsibility were present at different levels in my classroom. On the basis of my findings I make a number of recommendations for my own further practice and for other teachers.

This research examines the effects of forensic deoxyribonucleic acid (DNA) evidence on decisions in the courts and on the conduct of criminal investigations. To assess effects on court decisions, quantitative analyses were conducted using primary data from the State of Queensland. A control-comparison method was used to assess the effects in court, and this was made within a context of other evidentiary and extra-legal factors that had a bearing on case outcomes. These other factors included defendant confessions, independent witness testimony and fingerprint and photographic evidence. A sample of 750 cases referred by police for prosecution and finalised past the appeal stage in court, was selected for examination. Half of these cases utilised DNA evidence, while the other half, as a control group, did not. Cases were selected in four categories: sexual offences, serious assaults, homicides and property crime. Data on the cases were analysed using advanced statistical methods and predictor models were developed to demonstrate how, given case configurations, the addition of DNA evidence could potentially alter court outcomes. Results for the three serious offence types were that DNA evidence emerged as a positive predictor that prosecutors would pursue cases in court, and it demonstrated a powerful influence on jury decisions to convict. Incriminating DNA evidence demonstrated no significant effect on inducing guilty pleas from defendants for serious crimes against the person. However, it did correlate significantly to cases reaching court and to guilty pleas being entered for property offence cases. The analysis of the effects on investigations relies on data from jurisdictions other than Queensland. Secondary data and the literature were used to assess the potential for strategically using forensic intelligence, along with dedicated investigative resources, to reduce property crimes like burglaries and car thefts. In the one study available that employed adequate research methods, three patrol areas in New South Wales, where a police operation was trialled, were compared to other areas that acted as a control. The police operation aimed at 100% attendance at property crime scenes, the use of intelligence from DNA and fingerprint identifications and specialised investigative resources to reduce crime levels. While the operation failed to achieve its goal, it did provide some valuable lessons. The effectiveness of the national criminal DNA database in the UK, reputed to lead the world, was then evaluated in relation to domestic burglaries. Its Australian CrimTrac counterpart did not commence operations until March 2003, and by 2004 was not operating at maximum capacity. Because no published studies were located that measured any effects of the UK database on crime levels, the criterion selected to measure performance was the proportion of convictions achieved through the database to reported crime. For domestic burglaries, this ratio was calculated from secondary official data to be close to one percent (0.01), a figure that included the additional convictions achieved through the intelligence that the database provided. The research also examined forensic DNA in relation to issues of privacy and civil liberties. Privacy issues are discussed beginning with an historical background to the use and misuse of genetic data. This includes the searches for a 'criminal gene' and for genetic links to criminal behaviour. DNA databases are contrasted with databanks, and it is questioned, since we leave our DNA wherever we go, whether it really is private. Civil liberties issues that are discussed include whether providing DNA is a form of self-incrimination; how DNA has helped exonerate the convicted innocent; wrongful convictions based on flawed DNA evidence; whether occasional 'mass screenings' with DNA are a reversal of the onus of proof; concerns with DNA databases and 'function creep', and the planting or 'forgery' of DNA evidence including the use of amplicon contamination. In the final chapter, a balance is sought between on one hand, the goal of police and government to provide a safe society, and on the other, the rights to privacy and civil liberties expected by individuals in Western liberal democracies. The chapter addresses the issues of concern raised in the earlier chapter about privacy and civil liberties, and makes recommendations on how these may be resolved. The general approach favoured is to increase police powers in specific situations, but to couple these with the protection of individual rights through greater regulation of those powers. The research also developed a case prioritising system aimed at helping clear laboratory backlogs.

This thesis addresses different aspects of spatial data handling in connection with investigations of large rockslides. As such, most of the research was carried out in a cross disciplinary and highly applied context. The focus of the thesis is on spatial data handling methodology which directly or indirectly can be used to support in rockslide investigations. Rockslide investigation is a comprehensive term covering all aspects of the evaluation process; from the initial planning of field investigations to data analysis and communication of final results. Central topics addressed in this thesis are; a) How data reduction affect the geometrical accuracy of digital terrain models b) How interactive geometric modelling and geovisualization can be used in complex rockslide investigations and c) How statistical analyses can be used to evaluate displacement measurements of unstable rock slopes. Digital terrain modelling forms an important component of the methodology used for rockslide investigations. The first subtopic addressed in this thesis is related to the construction of Triangulated Irregular Networks (TINs) from Light Detection and Ranging (LIDAR) data. As the LIDAR technology tends to generate large data volumes, the resulting terrain models are generally too large to be efficiently handled by ordinary workstations. Therefore, comparisons of various data reduction (decimation) methods were conducted. Their performances were evaluated by means of deviations from terrain models constructed from full datasets. Evaluation criteria included deviations in volume, surface area and elevation. The results showed that the method using a vertical point selection threshold combined with a data dependent triangulation had the overall best performance when tested on 30 different test datasets. The main objective of the geovisualization part of this thesis was to determine the geometric shapes and locations of potential basal sliding surfaces, for the Åknes rockslide in western Norway, along with the volumes of unstable rock associated with different sliding scenarios. The Åknes rockslide is one of the world's most investigated rockslides due to its potentially catastrophic consequences. A custom written geovisualization application for the Åknes investigation provided the visual context needed for data interpretation and interactive geometric modelling of sliding surfaces. This geovisualization approach enabled geoscientists to develop different sliding scenarios. A scenario putting the basal sliding surface at a depth of 105m to 115m below the topographic surface, delineating an unstable rock volume of 43 million m3, was considered as the most realistic. Statistical approaches for analyzing displacement measurements were also addressed in this thesis. Several methods including regression analysis, spectral analysis and hypothesis testing were demonstrated to measurements obtained from Global Positioning System (GPS), total stations and extensometers at the Åknes rockslide. Displacement measurements obtained from lasers and crackmeters at the Nordnes rockslide in Northern Norway were also analysed. As with the Åknes rockslide, the Nordnes rockslide has the potential for devastating consequences in terms tsunami generation. Consequently, thorough statistical analyses of the available displacement data are crucial in order to obtain accurate estimates for the displacement rates as well as for gaining insight into the sliding processes. Displacement data from both sites clearly showed seasonal variations but the overall long term displacements were regarded constant. Prediction intervals were derived from the current monitoring data from the Nordnes site. These prediction intervals are considered useful for evaluation of future displacement measurements.

Background. Foodborne disease is estimated to cause 48 million illnesses annually in the US resulting in 3000 deaths [1]. Although most infections occur as sporadic cases, outbreak surveillance offers valuable insight about the foods and pathogens responsible for illnesses [2]. A total of 1632 foodborne disease outbreaks were reported during 2011-2012 [3] and recent data indicates an overall decrease in the number of outbreaks reported each year [4]. Understanding which factors contribute to the successful identification of a food vehicle in a foodborne outbreak investigation is crucial for improving outbreak response [5-10]. The purpose of this study was to describe outbreak characteristics and to determine which may be associated with the success of a foodborne outbreak investigation (i.e. one in which a food vehicle has been reported). Methods. A foodborne disease outbreak was defined as the event in which two or more people acquired similar illnesses from consuming the same food or beverage. Outbreaks occurring in FoodNet sites during 2003 through 2010 were included in the analysis. Results. Data were available for 1441 (87%) of the 1655 foodborne disease outbreaks documented in FoodNet Outbreak Supplement forms from 2003 through 2010. A food vehicle was identified in 692 of the 1441 (48%) outbreaks. Six outbreak characteristics remained statistically significant in both univariate and multivariate analyses: environmental and/or food culture collection, FDA or state agriculture involvement, outbreak size, case-control studies, and number of fecal specimens tested for norovirus. Conclusions. Less than half of foodborne outbreaks examined here resulted in a food vehicle being identified. Having more robust resources available for outbreak detection and investigation may improve likelihood of a food vehicle being identified.