4,638 research outputs found

    Medical Schools, Students, and the Conscience Policy

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    Alternative approaches to education provision for out-of-school youth in Malawi:The case of Complementary Basic Education

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    Young people in Malawi face many challenges. Primary education is struggling with poor internal efficiency, low quality and poor educational outcomes. Access to post-primary education is limited and highly selective. The majority of young people who exit the formal education system dropout in the primary cycle. Few out-of-school youth have had access to technical, vocational or entrepreneurial training, or the chance to develop key skills to support and sustain livelihoods in the country’s predominantly rural-based economies. Until recently education and skills development for out-of-school youth was given scant attention at the national level. However, in response to growing concerns about the ability to meet Education for All (EFA) targets and to support poverty alleviation strategies, the Malawi government now acknowledges the need for alternative approaches to basic education in order to cater for out-of-school children and youth. In 2006, the Complementary Basic Education (CBE) programme was launched in Malawi, first piloted and then expanded across several rural districts in Malawi. This background paper presents an overview and analysis of the role of Complementary Basic Education in the educational provision for out-of-school youth. In doing so, it focuses on the expectations, participation and outcomes of older learners, as well as the challenges faced in the delivery of curriculum content and practical pre-vocational skills training in light of the differing needs of children and youth. It explores the interface between basic education and skills development and reflects on lessons to be learnt with regard to the design, implementation and mainstreaming of complementary and non-formal education programmes

    Employment of fine grain emulsions in aerial photography

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    Thesis (M.A.)--Boston UniversityThe general problem of this work is to determine the extent to which fine grain emulsions can be employed in aerial photography, with specific application to miniaturization. In such a study, the following factors become important: reduced scale, limited coverage, processing and enlargement technique, loss of speed through the use of finer grained emulsions. In this investigation, laboratory tests were made to study these factors. These tests were to study the relative performance of several systems (lens plus film) and to investigate methods of increasing the speed of fine grain emulsions without seriously affecting the grain size. Finally, flight tests were made to verify the results indicated by the laboratory tests. Miniaturization is defined as the use of 35 mm and 70 mm cameras in aerial photography. It has become important during the last few years because of increasing space limitations inside the aircraft. Besides the obvious saving in weight and space both in the plane and in the processing and storage of the photographs, the miniature camera has other advantages. Because of the short focal length of most miniature camera lenses, it is possible to construct a fast lens of high quality, reducing the exposure time, the time in which vibration and image motion can affect the image, and hence the degree of stabilization which the camera must maintain. On the negative side, the reduced scale necessitates the enlargement of all photographs before they can be used. This increases the relative effects of the grain of the emulsion and uneven development, as well as introducing an additional variable in the photographic process, enlargement. The camera used in this work was an Exacta VX, 35 mm, with an f/1.5 75 mm Biotar lens. This lens was chosen largely because of its wide aperture, but this could not be used under practical conditions because of serious vignetting at f/1.5. The film chosen for a standard of comparison was Aerographic Super XX with a standard development in D-19 to a gamma of 1.6 to 1.7. At the other extreme, with respect to speed and grain size, Microfile was chosen. This film is easily developed to gammas of 3 and 4, but for the purpose of this work, it was developed in D-23, diluted 1:1, to a gamma similar to Aero XX. As a compromise in speedand grain size, a German film, Perutz Pergrano, was chosen. This film has an ASA exposure index of 12 and medium grain. DevHopment was in D-19 to a gamma of 1.35. Because of the inherent low contrast of this film, the gammas of Aero XX and Microfile could not be attained. Extensive tests were run on the f/1.5 75 mm Biotar lens with all three types of film, low and high contrast resolution tar gets, and with and without a yellow filter. From the results of these tests, the area weighted average resolution, or AWAR, was calculated for each aperture-film combination. Then, under the conditions which would be used for the flight tests, the minimum shutter speed was calculated which would prevent the resolution from dropping below the AWAR because of image motion caused by the movement of the airplane with respect to the ground. Next a table was prepared showing the predicted maximum resolution obtained under varying illumination conditions, taking into account the effect on resolution of increasing the aperture or the exposure time. The results of this table, which were confirmed by the flight tests, were: 1) Microfile must be exposed at too wide an aperture to obtain any benefit from its small grain size, 2) Microfile which has been latensified by post-exposure to light (see below) produces the best results under good illumination, but also must be exposed at too wide an aperture under decreased illumination, and 3) Perutz Pergrano produces better results than Aero XX over a range of illumination of 32:1. Results of resolution tests on 2 tele-photo lenses were used to compare these lenses with the 75 mm Biotar. The best lens was the f/5.5 180 mm Tele-Xenar lens, which had a performance, in terms of ground detail resolved, equal to the Biotar lens. This result was verified by flight tests with the two lenses, and hence the use of tele-photo lenses is warranted in high altitude photography, where the decreased coverage can be overlooked. From previously unpublished data on four 50 mm lenses and one 58 mm lens, the AWAR was calculated and the results plotted and analyzed. The best of the 50 mm lenses was an f/1.5 Angenieux. When the f/2 58 mm Zeiss Biotar lens and the Angenieux lens were reduced to a common level by removing the scale, the two lenses were of approximately the same performance. Of the methods of increasing film speed before exposure (hypersensitization) and after exposure but before development (latensification), the best method tested was post-exposure to a dim light. For this purpose, a darkroom safelight with a yellow filter and reduced applied voltage was exposed to Microfile for 30 minutes at a distance of 18 feet. An increase in speed of 400% was obtained over its normal speed of 1 (because of underdevelopment). Equal treatment before exposure gave an increase of speed of only 15%. When the method was used under actual photographic conditions, post-exposure to light gave a somewhat greater increase in speed than 400%. Resolution tests showed a drop in resolution of 10%, but the resolving power was still greater than that of Perutz Pergrano. Other methods of hypersensitization and latensification which were tested were NaCl and Borax in solution, Mercury vapor, and combinations of ammonia and alcohol in solution. The maximum increase obtained from these methods was 50%. The increase in speed obtained on Microfile through post-exposure to light has brought the emulsion sensitivity to a minimum level for best results under normal illumination. Hence the grain size is also approximately at a minimum and this film, used in this way, provides maximum definition in terms of detail resolved. Then on the basis of X 8 enlargements of 35 mm negatives on Microfile which had been latensified in this manner, the conclusion is reached that 35 mm cameras may not be used as an unqualified substitute for aerial cameras. However they may prove valuable in some types of reconnaissance photography. The enlargement to 4 diameters of negatives on Microfile latensified and Perutz Pergrano produces good results. Since this is the amount of enlargement necessary to bring 70 mm negatives to approximately the size of a 9 X 9 inch photograph, 70 mm cameras may be used in connection with these films and others of similar characteristics to replace aerial cameras for many purposes. The major exceptions are in the production of photographs for use in surveying and photogammetric work, which require maximum definition at all levels of magnification. Aero XX is not recommended for use with miniature cameras in general because the lenses of these cameras are capable of higher resolution than this film can accomodate. At a drop in emulsion speled of 8 I from Aero XX, Perutz Pergrano may be used over an illumination range of 32:1, and still produce better results than would be obtained with Aero XX. This range might be extended even further through the use of hypersensitization and latensification methods, without seriously affecting the grain size of the emulsion. In conclusion, then, fine grain emulsions (i.e. finer grained than Aero XX) in connection with 70 mm cameras may be used to produce results satisfactory for many purposes in Aerial Photography. I would like to thank the following people for their contributions to the work involved in this thesis: Mr. Hutson Howell, Dr. F. Dow Smith, Mr. William Drumm, Mr. Hadrian Lechner, the staff of the Boston University Physical Research Laboratory, and Mrs. Jere Sanborn

    Machito and His Afro-Cubans: Selected Transcriptions

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    Machito (Francisco Raúl Grillo, 1909–1984) was born into a musical family in Havana, Cuba, and was already an experienced vocalist when he arrived in New York City in 1937. In 1940 he teamed up with his brother-in-law, the Cuban trumpeter Mario Bauzá (1911–1993), who had already made a name for himself with top African American swing bands such as those of Chick Webb and Cab Calloway. Together, Machito and Bauzá formed Machito and his Afro-Cubans. With Bauzá as musical director, the band forged vital pan-African connections by fusing Afro-Cuban rhythms with modern jazz and by collaborating with major figures in the bebop movement. Highly successful with Latino as well as black and white audiences, Machito and his Afro-Cubans recorded extensively and performed in dance halls, nightclubs, and on the concert stage. In this volume, ethnomusicologist Paul Austerlitz and bandleader and professor Jere Laukkanen (both experienced Latin jazz performers) present transcriptions from Machito’s recordings which meticulously illustrate the improvised as well as scored vocal, reed, brass, and percussion parts of the music. Austerlitz’s introductory essay traces the history of Afro-Cuban jazz in New York, a style that exerted a profound impact on leaders of the bebop movement, including Dizzy Gillespie and Charlie Parker, who appears as a guest soloist with Machito on some of the music transcribed here. This is MUSA’s first volume to represent the significant Latino heritage in North American music.https://cupola.gettysburg.edu/books/1106/thumbnail.jp

    Compound cycle engine for helicopter application

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    The Compound Cycle Engine (CCE) is a highly turbocharged, power compounded, ultra-high power density, light-weight diesel engine. The turbomachinery is similar to a moderate pressure ratio, free power turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military light helicopter applications. This executive summary presents cycle thermodynamic (SFC) and engine weight analyses performed to establish general engine operating parameters and configuration. An extensive performance and weight analysis based on a typical two hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a T-800 class gas turbine engine. The CCE had a 31% lower-fuel consumption and resulted in a 16% reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb-HP-HR and installed wet weight is 0.43 lbs/HP. The major technology development areas required for the CCE are identified and briefly discussed
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