1,362 research outputs found
Procurement and development program for nickel-cadmium cells to specification s-615-p-2 Technical status report no. 12, May 25 - Aug. 26, 1966
Procurement, development, and testing of nickel- cadmium cell
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Coal Ash Disposal Challenge (Part 1)
The Kay Bailey Hutchison Center for Energy, Law, and Busines
Autism and AAC: A Case Study
Past studies have shown that the use of Augmentative and Alternative Communication (AAC) has been successful in facilitating the communication needs for individuals with autism. AAC,as defined by the American Speech Language and Hearing Association, is ...a set of procedures and processes by which an individual\u27s communication skills (i.e., production as well as comprehension) can be maximized for functional and effective communication. It involves supplementing or replacing natural speech and/or writing with aided (e.g., picture communication symbols, line drawings, Blissymbols, and tangible objects) and/or unaided symbols (e.g., manual signs, gestures, and finger spelling) . The many types of AAC systems can be beneficial for multiple communication needs. Although there is a separation of systems, many say that all communication needs are met
High-frequency wave-propagation: error analysis for analytical and numerical approximations
In this thesis we investigate a specific type of semilinear hyperbolic systems with highly oscillatory initial data. This type of systems is numerically very challenging to treat since the solutions are highly oscillatory in space and time. The goal is to derive suitable analytical and numerical approximations. Based on the classical slowly varying envelope approximation (SVEA), an improved error estimate is proven for this analytical approximation. The envelope equation avoids oscillations in space, making this approximation attractive for numerical computations. Furthermore, more accurate analytical approximations are obtained by extending the ansatz of the SVEA. In addition to the analytical study of the SVEA two numerical time integrators are constructed and analyzed without any step-size restrictions. Numerical examples are provided to illustrate the theoretical results.
Finally, a complementary approach is presented which address both problems, the oscillations in space and time, simultaneously
A Case Study of Tent and Trailer Camping in the Great Smoky Mountains National Park
The purpose of this thesis was to study the problems associated with the growing demand for tent and trailer camping facilities. In order to study the problem under controlled conditions, a case study of the Great Smoky Mountains National Park was undertaken. The study reviewed campers on three levels-- wilderness, primitive, and modern. Each of these categories was then divided into ten and trailer campers and a model campground facility developed for each. The facilities which presently exist in the park were then compared with the models. The comparison revealed that study area facilities were lacking in many of the conveniences desired by campers. The differences between the model and the study area facilities were most dramatic in the modern campgrounds where no electrical or water hookups were provided for individual sites nor were showers available for the campgrounds.
Overall the results of the study revealed that the Great Smoky Mountains National Park, like most of the recreational facilities across the country, has a growing demand for its camping facilities. The study further indicated that because of the increased demand park authorities have experienced an increase in littering, traffic congestion, vandalism, destruction of vegetation, and an increased workload for park personnel.
Potential for the development of commercial camping outside the study area appears to be good. Physically the area adjacent to the Great Smoky Mountains National Park is similar to that found inside the park. To date commercial camp developers have not taken full advantage of this factor, but indications are that demand for quality facilities will increase, forcing commercial interests to reevaluate future development plans.
After completing the review of commercial developments surrounding the study area including the growth trends for study area visitation and existing camping facilities, the following recommendations were made:
1. Develop a system of reservations and central check-in stations.
2. Allow no additional expansion of existing camping facilities.
3. Undertake the redesign of existing park facilities.
4. Remove horse traffic from hiking trails.
5. Undertake a systematic removal of internal trailer camping with a greater emphasis on external commercial facilities.
In conclusion, if objectives established by the National Park Service for the maintenance and operation of our parks are to be met, restrictions on use patterns and levels will have to be rigidly enforced. It is also essential that park officials and private enterprise work together to protect the environment by controlling development in the area. Unless positive measures can be taken to protect the park and its perimeter from the growing pressures of increasing visitation much of the natural beauty of the area will be destroyed
Le coût économique des politiques de réduction de la mobilité
Le système de transport, qui joue un rôle décisif dans le dynamisme économique des grandes agglomérations, se trouve confronté dans la plupart de ces villes à une double difficulté environnementale et financière (financement des infrastructures pour accompagner l'augmentation de la demande de transport, financement des transports collectifs, etc.). Parmi les raisons qui sont invoquées pour rendre compte de ces difficultés, on trouve de plus en plus cité l'étalement urbain. Des comparaisons entre les grandes villes mondiales [Base Millenium UITP, 1996] peuvent montrer en effet que les villes les moins denses sont aussi les villes les plus consommatrices d'énergie : le système de transport très dépendant de la voiture particulière y est très coûteux pour la collectivité, les systèmes alternatifs plus respectueux de l'environnement, et particulièrement les transports collectifs, ont du mal à s'imposer tant la concurrence avec la voiture est difficile. On trouve dans la littérature deux approches pour traiter ce problème : certains insistent sur les gains de vitesse offerts par le système de transport, d'autres portent un regard plus économique. Ces deux approches conduisent à des préconisations de politiques publiques assez différentes qui font l'objet de virulents débats au sein de la communauté académique et des administrations. Cet article expose le cadre analytique dans lequel sont faits les développements et se propose de simuler les effets de ces politiques sur le surplus économique en utilisant un modèle multimodal (MATISSE_ INRETS), et en retenant les dernières valeurs tutélaires françaises proposées par l'administration française en 2000 (valeur du temps, valeurs environnementales).Politique des transports urbains ; coût économique ; maîtrise de la mobilité ; modèle multimodal MATISSE (INRETS)
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