Fuel Injector: Air swirl characterization aerothermal modeling, phase 2, volume 2

A well integrated experimental/analytical investigation was conducted to provide benchmark quality data relevant to prefilming type airblast fuel nozzle and its interaction with combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) equipment was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM) and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Fuel injector: Air swirl characterization aerothermal modeling, phase 2, volume 1

A well integrated experimental/analytical investigation was conducted to provide benchmark quality relevant to a prefilming type airblast fuel nozzle and its interaction with the combustor dome air swirler. The experimental investigation included a systematic study of both single-phase flows that involved single and twin co-axial jets with and without swirl. A two-component Phase Doppler Particle Analyzer (PDPA) was used to document the interaction of single and co-axial air jets with glass beads that simulate nonevaporating spray and simultaneously avoid the complexities associated with fuel atomization processes and attendant issues about the specification of relevant boundary conditions. The interaction of jets with methanol spray produced by practical airblast nozzle was also documented in the spatial domain of practical interest. Model assessment activities included the use of three turbulence models (k-epsilon, algebraic second moment (ASM), and differential second moment (DSM)) for the carrier phase, deterministic or stochastic Lagrangian treatment of the dispersed phase, and advanced numerical schemes. Although qualitatively good comparison with data was obtained for most of the cases investigated, the model deficiencies in regard to modeled dissipation rate transport equation, single length scale, pressure-strain correlation, and other critical closure issues need to be resolved before one can achieve the degree of accuracy required to analytically design combustion systems

Inter-agency Cooperation and Good Tax Governance in Africa

In 2015, the Vienna University of Economics and Business (WU) and the African Tax Institute at the University of Pretoria launched a project to identify the links between corruption, money laundering and tax crimes in Africa. The project promotes the concepts of good tax governance and the importance to economic development of a tax system that is transparent and free of corruption. The project explores how law enforcement agencies and tax authorities can best cooperate to counter corruption and bribery. The project was initially aimed at three focus countries, namely, Ghana, Nigeria and South Africa, but soon was extended to other African countries. This is a joint initiative with the United Nations Office on Drugs and Crime (UNODC) and is also supported by the World Bank. This book brings together a series of background papers prepared for the Conference on Inter-Agency Co-operation and Good Tax Governance in Africa held at the University of Pretoria in July 2016. After a rigorous double peer-review process, the papers were revised by the authors. We express our gratitude to and acknowledge the services of the following peer reviewers: Tom Balco; Carika Fritz; Leon Gerber; Willem Jacobs; Benjamin Kujinga; Thabo Legwaila; Annet Oguttu; Dirk Scholtz; David Solomon; and Xeniya Yeroshenko. Finally, we express our sincere gratitude to all the research and administrative assistants who contributed to the Good Tax Governance in Africa Project. This book pays tribute to their efforts. Jeffrey Owens, Rick McDonell, Riël Franzsen and Jude Amos (Vienna and Pretoria, November 2017

Hypertext versus Footnotes: High School English Learners’ Online Reading Recall

This study considers forty adolescent English Language Learners who read a passage online containing additional information available through either hypertext links or footnotes. Participants were attending a special high school for English learners at the time of the study. Two versions of the text were offered, one with hypertext and the other with footnotes, and participants were randomly assigned to the footnote or hypertext condition. Answers to multiple choice questions showed no significant difference between groups in recall of the reading under the two conditions, in contrast with an earlier study of learners in higher education settings whose recall of reading with hypertext was significantly lower than with footnotes. Learners’ ratings of perceived comprehensibility of the 2 texts was also not significantly different. Additional interpretive data came from focus group interviews involving all of the participants

Theoretical analysis of a novel integrated energy system formed by a microturbine and a exhaust fired single-double effect absorption chiller

Integrated Energy Systems (IES) combine a distributed power generation system (DG) such as a microturbine generator (MTG) or a fuel cell with thermally activated technologies (TAT) such as absorption cooling. This integration maximizes the efficiency of energy use by utilizing on-site most of the waste heat generated by DG, and reduces harmful emissions to the environment. This study investigates the energy and exergy performance of an IES. This system is comprised of an MTG with internal recuperator and a novel absorption cooling cycle. The absorption cycle is a single-double effect exhaust fired cycle, which recuperates the heat exchanged from the MTG exhaust gases using two generators at two different levels of temperature. The selection of the DG element, the TAT element and their internal configurations is based upon a real IES commercial unit that has been tested in the APEP-UCI DG testing facilities in Irvine, California. This unit has an electrical power capacity of 28 kW and a cooling capacity of 14 refrigeration tons (49.2 kW). Inputs for the thermodynamic models developed for the MTG and for the absorption cycle are derived from experimental variables that will be controlled in the testing phase. The MTG model is using empirical correlations for key model parameters (pressure ratio, turbine inlet temperature, etc.) from previous studies in order to predict the observed change in performance with part load operation. The calculated mass flow rate and temperature of the exhaust gases are inputs for the absorption cycle model, together with cooling and chilled water inlet temperatures and flow rates. Heat and mass transferefficiencies along with heat transfer coefficients for the suite of heat exchangers comprising the single-double effect absorption cycle are determined from proprietary testing data provided by the manufacturers

a retrospective cohort analysis

Background Allergy immunotherapy is an effective treatment for patients with allergic rhinitis whose symptoms are unresolved with pharmacotherapy. Allergy immunotherapy for grass pollen-induced allergic rhinitis is available in three modalities: subcutaneous immunotherapy and sublingual immunotherapy as a tablet or drop. This study aimed to understand trends in allergy immunotherapy prescribing and practice patterns for grass allergies in adult and paediatric patients in Germany. Methods A retrospective cohort study was conducted using IMS Disease Analyzer in Germany. Patients with an allergy immunotherapy prescription for grass pollen (Anatomical Therapeutic Chemical [ATC] classification code V01AA02) from September 2005 to December 2012 were included in the study. General Practitioners (GPs), dermatologists, Ear, Nose and Throat (ENT)-specialists, paediatricians and pneumologists were included as the allergy immunotherapy prescribing physicians in the study. Descriptive analyses were conducted on patient characteristics at index and prescribing physician specialty; a test for trend was conducted for timing of initiation of first allergy immunotherapy prescription in each annual prescribing season. Results Eighteen thousand eight hundred fifty eligible patients were identified during the study period. The majority of patients received subcutaneous immunotherapy; however, the proportion of patients receiving sublingual immunotherapy tablets increased from 8 % in 2006/2007 to 29 % in 2011/2012 (p < 0.001). Initiation of subcutaneous immunotherapy and Oralair® generally peaked during each prescribing year in two seasons (September- October and January) while GRAZAX® prescriptions peaked in autumn (September- October). ENT-specialists and dermatologists were the largest allergy immunotherapy prescribers in adults, while paediatricians and ENT-specialists were the largest prescribers of allergy immunotherapy in paediatric patients. Conclusions Subcutaneous immunotherapy remained the dominant allergy immunotherapy modality for grass pollen-induced allergic rhinitis in Germany for adult and paediatric patients; however, there was a marked increase in proportion of patients receiving sublingual immunotherapy tablets from 2006/2007 to 2011/2012, after their introduction to the market in 2006. ENT- specialists, dermatologists and paediatricians were responsible for the majority of prescribing. The predominance of particular modalities within certain physician specialties likely reflects different treatment goals or needs

Geophysical Expression of the Northern Part of the Mono-Inyo Volcanic Chain, Mono Basin, California

The Mono Domes are located at the northernmost end of the Mono-Inyo volcanic chain just north of the Long Valley Caldera and include more than 30 overlapping domes and coulees that follow an arcuate trend. A shallow basement high, possibly bounded by a fault, as suggested by potential-field models of data collected in Mono Basin, California, may have influenced the geometry and location of the Mono Domes. Over 320 new gravity stations and approximately 297 line-km of ground magnetic data were collected during the summer of 2010 to investigate the subsurface structure of the Mono Basin. Regional gravity data were collected throughout the basin, and ground magnetic data were collected on major roads along numerous transects throughout the region, one of which was coincident with a seismic refraction line. Gravity and magnetic data were compiled with pre-existing data from studies dating back to the 1960\u27s to produce a new regional isostatic gravity anomaly map and ground magnetic profiles throughout the basin. Aeromagnetic and ground magnetic data revealed an anomalous ring-shaped magnetic high centered over Aeolian Buttes, whose eastern margin follows the arcuate trend of the Mono Domes. This magnetic high is essentially coincident with what Kistler (1966) inferred to be a ring-fracture. Two-dimensional forward modeling of potential field data along a profile across the basin suggests a basement high, or ridge, at roughly 700 m depth, the eastern edge of which lies beneath the Mono Domes. The basement ridge is probably fractured, as suggested by potential field data, indicating a possible pre-existing fault beneath the Mono Domes. This fault is along the eastern edge of the basement ridge and could have served as a conduit for the Mono Domes feeder dike

How to Best Support Individuals Growing up with a Special Needs Sibling

The purpose of this study was to understand the emotions of a neurotypically developing sibling. This study also attempted to understand how caregivers can best support the neurotypical sibling in the areas of self-concept and overall well-being. The gap is knowledge is how to better support neurotypical developing siblings specifically in the areas of self-concept and overall well-being. Three participants were interviewed to gain insight about their experiences with their special needs sibling. Participants who participated in a support group for neurotypical developing children with a SNS were surveyed to gain insight about their experiences with the support group. Through the qualitative method approach, it was found that the neurotypical sibling experiences a variety of emotions that include happy, calm, angry, anxiety, worry, and accepting. The survey responses provided evidence that support groups are beneficial and can provide emotional support in the areas of self-concept and overall well-being