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A major technological challenge in 21st century is the transition from fossil-fuel based energy to renewable energy. Solid-state electrochemical devices such as batteries, capacitors, fuel, cells, solar cells, and sensors are some of the critical components expected to play a dominant role towards alternative sustainable energy. Fuel cells are devices that convert chemical energy of the fuel into usable electricity and heat without combustion with the only by product being pure water. An arising problem in today's world is the destruction of the ozone layer because of the emissions and harmful gases that vehicles are giving off. Forget ethanol or biodiesel. The next big thing in automotive fuel may very well be hydrogen. Hydrogen-powered fuel cell vehicles could play a central role in future transportation systems. They produce only electricity, heat, and water at point of use. They could also use predominantly domestic—potentially renewable—energy supplies instead of imported oil to help meet one of our most pressing energy needs. Consequently, there has been great interest in hydrogen as a primary "energy carrier" displacing petroleum-based fuels. Automakers rapidly are closing in on making hydrogen fuel cell and promote policies to create the "hydrogen highway, private businesses and government agencies are increasingly deploying fuel cells for stationary power applications. Stationary fuel cells are a technology that is commercially available, reliable, suitable to a wide variety of applications, declining in costs, and with federal and state support, becoming more affordable.

Background: Height measurement is one of the common essential anthropometric measurements in clinical pediatrics. The most accurate method of determining a child height is to measure the height. However, in emergency situations and some resource limited settings, obtaining the actual height of a child may not be feasible hence the need to estimate. The most common age-based formulae for height estimation in children is 6n + 77 where n = age in years. The accuracy of this height estimation formulae has not been assessed in developing setting like ours with high prevalence of malnutrition. This study therefore sought to evaluate the accuracy of the height estimation formula in children in communities across Enugu southeast Nigeria. Method: Children 2-12 years old who met the inclusion criteria were enrolled over 12 months from three of the 17 Local Government Area of Enugu State. Height was measured using a standard stadiometer and estimated height was calculated 6n + 77. Data collected was analyzed using SPSS. Result: Of the 4046 children enrolled, majority (86.1%) were of normal height for age while 2.6% were stunted. The formula underestimated height of children in younger age bracket and overestimated height in older children. Overall, the estimated height using the formula was within ±10% agreement of the actual height of surveyed children in 77.0% of children surveyed. Conclusion: The 6n + 77 formula is a reasonable but not entirely accurate for height estimation for children in our setting. Keywords: Children, Height, Estimation, Accuracy

The author sets out to achieve a better measurement of interorganisational power in distribution channels.

This study reports on the development and validation of the Civic Engagement Scale (CES). This scale is developed to be easily administered and useful to educators who are seeking to measure the attitudes and behaviors that have been affected by a service-learning experience. This instrument was administered as a validation study in a purposive sample of social work and education majors at three universities ( N = 513) with a return of 354 (69%). After the reliability and validity analysis was completed, the Attitude subscale was left with eight items and a Cronbach's alpha level of .91. The Behavior subscale was left with six items and a Cronbach's alpha level of .85. Principal component analysis indicated a two-dimensional scale with high loadings on both factors (mean factor loading for the attitude factor = .79, and mean factor loading for the behavior factor = .77). These results indicate that the CES is strong enough to recommend its use in educational settings. Preliminary use has demonstrated that this scale will be useful to researchers seeking to better understand the relationship of attitudes and behaviors with civic engagement in the service-learning setting. The primary limitations of this research are that the sample was limited to social work and education majors who were primarily White ( n = 312, 88.1%) and female ( n = 294, 83.1%). Therefore, further research would be needed to generalize this research to other populations.

This is the summary of the final report of a project to evaluate the validity of the NEF measure of aircraft noise. This final report is intended to directly respond to the specific requirements of the original proposal. A database of references and two technical reports have already been sent to Transport Canada as part of this project. Summaries of the previous technical reports are included in the Introduction of this report. The highlights of this final report include:General RecommendationsUpgrade (and provide ongoing support for) the continuing development of the NEF_1.7 program.Establish and publish noise criteria for all major Canadian airports in terms of NEF values and supplementary single event noise criteria.Undertake a major Canadian survey of response to aircraft noise to include: isolated single event type problems, various smaller airport situations, tests of various time-of-day weightings, evaluation of the long term effectiveness of additional home insulation, and to provide a comprehensive calibration of the NEF measure.Support updating of the CMHC document on new housing and aircraft noise.Consider adopting an A-weighted NEF measure.Encourage all levels of government to follow a uniform national approach to the management of airport noise in Canada. ; Disponible aussi tôt que possible Le présent document est un résumé du rapport final d'un projet visant à évaluer la validité de la mesure NEF du bruit des aéronefs. Le rapport final donne suite aux exigences particulières du projet original. Une base de données regroupant les références bibliographiques, ainsi que deux rapports techniques ont déjà été envoyés à Transports Canada dans le cadre du projet. Vous trouverez dans l'introduction du présent rapport des résumés des rapports techniques antérieurs. Voici les principaux éléments du présent rapport :Recommandations généralesPerfectionner le programme NEF_1.7 (assurer le soutien continu du développement du programme).Déterminer et publier les critères de bruit se rapportant aux aéroports principaux du Canada en valeurs NEF, de même que les critères de bruit se rapportant aux épisodes de bruit isolés additionnels.Entreprendre une étude à l'échelle nationale sur la réaction des gens face au bruit des aéronefs, dans laquelle on traitera des points suivants: problèmes découlant des épisodes de bruit isolés, situations variées se produisant dans les petits aéroports, essais de différentes méthodes de pondération par heures du jour, évaluation de l'efficacité à long terme de l'isolation additionnelle des maisons, etc. Cette étude permettra l'étalonnage complet de la mesure NEF.Soutenir la mise à jour du document de la SCHL sur les nouveaux secteurs résidentiels et le bruit des aéronefs.Considérer l'adoption d'une mesure NEF pondérée A.Encourager tous les paliers de gouvernement à suivre une démarche nationale uniforme en ce qui a trait à la gestion des bruits que présentent les aéroports au Canada. ; Peer reviewed: No ; NRC publication: Yes

Proceedings of the 2001 Winter Simulation Conference B. A. Peters, J. S. Smith, D. J. Medeiros, and M. W. Rohrer, eds. ; The military develops simulations to analyze nearly every aspect of defense. How accurate are these simulations and to what extent do they produce dependable results? Most guidance available to DoD analysts provides broad recommendations geared towards management and coordination of the validation processes. Here, we focus on practical validation from the analyst's perspective in the form of a case study. The platform used is the theater missile defense (TMD) aspects of Extended Air Defense Simulation (EADSIM) and a new simulation called Wargame 2000. The focus is not to validate Wargame 2000 but to develop real, usable tools for analysis. Measures of effectiveness include defense battery search, engagement and intercept times against threat missiles. Insight is provided into developmental and data production issues making the validation process more effective and meaningful.