3,725 research outputs found
Constrained Aerodynamic Adjoint Optimisation of Supersonic Manoeuvre Wings
Supersonic manoeuvring aircraft are designed to be efficient during aerobatic or high-load flight conditions at supersonic speeds, but are also usually required to also be efficient at other flight conditions. For example, transonic and subsonic cruising and manoeuvring. Aerodynamic flow around wings at supersonic manoeuvring flight conditions can exhibit a complex variety of structures and patterns, presenting a unique challenge for aerodynamic design methods. This work aims to seek an understanding of the effect of these complex flow features on aerodynamic efficiency as well as develop optimisation methods to help find the most efficient geometries which balance these flow features to their benefit.
A lift-constrained adjoint optimisation strategy for supersonic manoeuvring wings has been presented and used to produce a minimum pressure-drag conical camber design for a 57 degree delta wing. The computational efficiency of this strategy has been compared with a similar strategy for the same optimisation problem, and the resulting designs from each process have been interrogated. The optimised conical wing design has been evaluated using RANS analysis and compared with a wing designed using an analytical method and a wing with zero camber.
The lift-constrained adjoint optimisation strategy has been applied to the camber design of two supersonic manoeuvre wing concepts and the resulting minimum pressure drag designs have been evaluated and compared using RANS analysis. Supersonic and transonic pitching moment constraints were then included in the optimisation problem in a novel design methodology, in an attempt to minimise pitch trim requirements at two design points whilst improving efficiency at the supersonic manoeuvring condition. The resulting designs were then evaluated using RANS at both supersonic and transonic speeds and compared with the minimum pressure drag design examples. The most favourable wing design was found to exhibit novel and desirable flight characteristics across a range of flight conditions
History of Slavery in Texas and the Southwest Number 10 Free Negroes in Texas to 1860
The purpose;of this study is to present the free Negro in and to observe his status in a co-existent culture, also to arrive at a conclusion that will portray the true character of the free Negro in the Texas Community.
The scope of this study entails the coming of the Anglo-white, circa 1820, to the year of 1860 which marks the conflict between the North and South.
The method that has been employed in presenting the Free Negro in Texas is topical. This method has been chosen because it enables the writer to group the information in such a category so as the reader may obtain a clear concept of the factors that are involved in this study.
The sources that are used in the study are comprised of census reports, petitions, deeds and records, state congressional journals, newspapers, biographies, general and special histories, and articles and essays found in the professional journals
DECREASING FOOD WASTE THROUGH INCREASED AWARENESS AT A UNIVERSITYâS DINING FACILITIES
Purpose: The current study was conducted to assess the effectiveness of a semester-long anti-food waste campaign regarding university student dinersâ food waste behaviors.
Originality/Value: Food waste and specifically post-consumer food waste has become one of the most critical concerns in recent years. Post-consumer food waste has also become a major concern and area of interest on U.S. college and university campuses, as numerous administrators have started considering the impact of waste within their dining operations. However, there have been limited examples of how to successfully cut down on food waste that is produced by students. Therefore, this study offers insight into how compiling baseline numbers for food that is wasted on campus and actively engaging and informing students of their impacts, can successfully help decrease the amount of waste that is produced on a university campus.
Relevance to the Topic: Food waste on college and university campuses has become increasingly important to administrators and foodservice providers due to environmental and fiscal concerns. Finding ways to successfully decrease the amount of food that is wasted has the potential to both save money and improve regional waste management systems. However, to cut down on the amount of waste produced by students, they must first be made aware of their personal impact, and the overall goals of the university. Thus, by obtaining information regarding the amount of food that is wasted in a given week, and developing an anti-food waste campaign, administrators and foodservice providers may be able to recognize a decrease in postconsumer food waste on their campuses.
Design/Methodology/Approach: Utilizing a quasi-experimental design, the current study assessed the effect that a semester-long anti-food waste campaign had on student dinersâ food waste behaviors. The project was conducted over lunch hours (11:30-1:30) and dinner hours (5-7) during the first and last full weeks of classes during the Fall 2016 semester.
Key Findings: Overall post-consumer food waste decreased by almost 10% regarding the two weeks that were tested, this despite an increase of nearly 2400 diners in the second week.
Implications for Practice: Results indicate that by actively engaging university students, and increasing awareness of food waste on campus, foodservice operators can potentially decrease the amount of food that is wasted, thus increasing sustainability efforts and lowering the overall negative impact on the global environment
Changing Classroom Practice: The Evaluation of the School Network Learning Project in Jordan
In 2007, the Columbia University Middle East Research Center (CUMERC), with the support and patronage of Her Majesty Queen Rania Al Abdullah, facilitated the founding of the Queen Rania Teacher Academy (QRTA) to help advance education in Jordan and throughout the Middle East. Through CUMERC, QRTA and Teachers College, Columbia University (TC) formed a new partnership whose goal was to use high quality in-service training to improve the quality of the public schools in Jordan. The Consortium for Policy in Education at TC (CPRE) took on this work and began collaborating with QRTA to engage current educators in the adoption and use of evidence-based instructional practices in Jordanâs elementary and secondary schools. This initiative became known as the School Networks Learning Project and supported networks of schools in different regions of the country as vehicles for providing professional development of teachers in English, mathematics, and science as well as leadership training for principals and education supervisors to support the desired changes in classroom practice.
Five core practices were emphasized during the professional development with the goal being that teachers would focus on these practices and take them back to their classrooms. Schools and teachers made a 2 to 3 year commitment to the project. At the time of the writing of this report, three cohorts have completed the Project and two additional cohorts have begun the Project. Across the three completed cohorts, 2,158 teachers, 894 school leaders, and 104 other educators participated in the School Network Project, totaling 3,130 participants over the almost six years of the Projectâs implementation
Rare plants of the Mauna Loa Special Ecological Area, Hawai'i Volcanoes National Park
Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.The montane and sub-alpine zones of the Mauna Loa Strip in Hawai'I Volcanoes National Park (HAVO) contain some of the most intact native vegetation found within the Park, and most of the study area has been considered a Special Ecological Area (SEA) since the mid 1980s. The Mauna Loa Strip was grazed by cattle prior to its inclusion in Hawai'i National Park. Feral goats and pigs were removed in the 1970s and 1980s, when two units of the SEA were completely fenced. The area above the upper unit, enclosed as the alpine unit in 1999, still supports an unknown number of feral goats and mouflon sheep, but feral animal removal is planned. The present survey was initiated to provide information to managers on the distribution and status of the endangered, threatened, and rare plant species of the Mauna Loa SEA. Population monitoring of selected species was conducted to determine how rare plants were responding to management practices, largely the removal and interdiction of feral animals.Cooperative Agreement # U.S. Geological Survey 1445-CA09-94-1066-0
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Session D1: Towards Effective, Bi-Directional Selective Fish Passage
Abstract:
Barriers interfere with aquatic connectivity by preventing or limiting migratory fishes from spawning and other life history processes, and there is increasing pressure to restore connectivity. However, conflicting management objectives exist in many jurisdictions where barriers to fish movement inhibit the restoration of native fishes but protect native fish communities above barriers from undesirable invasive species. In the Laurentian Great Lakes, barriers are an important management tool in the control of invasive Sea Lampreys. Sea Lampreys remain highly destructive in the Great Lakes, and are a constant threat to a 7 billion dollar fishery. Developing selective, effective bi-directional fish passage to remove Sea Lampreys while allowing the passage of native fishes has become an issue of great importance for Great Lakes fisheries managers. To date, efforts have included a variety of approaches including velocity barriers, seasonal barriers, trap-and-sort fishways, and eel ladders. The integration of emerging technologies, such as push-pull and electrical and pheromone guidance and advances in engineering, such as eel-style ladder traps are providing hope that better selective, effective bi-directional fish passage solutions are possible. The Great Lakes Fishery Commission is developing a research theme specific to selective bi-directional fish passage in the hopes of resolving the conflict between aquatic fragmentation and invasive species control
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