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The mid-1990s marked a paradigm shift in the way physical activity is promoted, and walking is now considered the most suitable type of physical activity for widespread promotion. Accurate measurement underpins public health practice, hence the aims of this chapter are to: (1) provide a typology for the measurement of walking; (2) review methods to assess walking; (3) present challenges in defining walking measures; (4) identify issues in selecting instruments for the evaluation of walking and (5) discuss current efforts to overcome measurement challenges and methodological limitations. The taxonomy of walking indicates that secondary purpose walking is a more complex set of behaviours than primary purpose walks. It has many purposes and no specific domain or intensity, may lack regularity, and therefore poses greater measurement challenges. Objective measurement methods, such as accelerometers, pedometers, smartphones and other electronic devices, have shown good approximation for walking energy expenditure, but are indirect methods of walking assessment. Global Positioning System technology, the ‘Smartmat’ and radio-frequency identification tags are potential objective methods that can distinguish walkers, but also require complex analysis, are costly, and still need their measurement properties corroborated. Subjective direct methods, such as questionnaires, diaries and direct observation, provide the richest information on walking, especially short-term diaries, such as trip records and time use records, and are particularly useful for assessing secondary purpose walking. A unifying measure for health research, surveillance and health promotion would strongly advance the understanding of the impact of walking on health.
State environmental agencies have been organized independently with a variety of structural schemes, and are responsible for the bulk of administration of federal…
State environmental agencies have been organized independently with a variety of structural schemes, and are responsible for the bulk of administration of federal environmental policy, such as the Clean Air Act. Using statistical models of air quality outcomes, this research compares three competing typologies for capturing agency differences: Ringquist (1993b), Lester (1990), and Wilson (1989). The findings indicate the most commonly used measure of organization, Ringquist (1993b), may be the weakest in comparison. Additionally, both Lester (1990) and Wilson (1989) show interesting advantages in comparison to each other. The findings provide some interesting insights into the difficult task of measuring organization.
THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments…
THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments and the well known German V‐2 rockets used this material as an oxidizer. However, its effect on non‐metallic materials ordinarily used in rocket systems was not investigated until recent years. This investigation was prompted by phenomena which had been experienced by rocket engine and rocket aircraft manufacturers and by suppliers of the material. It was observed that when some organic materials came in intimate contact with liquid oxygen they became prone to detonation when subjected to certain impact energies. This was undoubtedly due to the formation of unstable organo‐peroxide compounds which when impacted released high levels of energy resulting in an explosion. Specifically, when liquid oxygen was accidently spilled on asphalt and inadvertently stepped on, the asphalt would often explode. Also, leather gaskets immersed in liquid oxygen and subjected to surge impact detonated with disastrous effects.
Some recent research lends support to the evolving idea that management is specific to the situation, so that neither the work nor development of managers can be…
Some recent research lends support to the evolving idea that management is specific to the situation, so that neither the work nor development of managers can be considered without reference to many variables. Case studies of four organisations and interviews with more than fifty managers in the construction industry suggest that managers rely heavily on interpersonal, decisional and problem handling skills, which they consider are largely derived from their work experiences. Management development programmes may assist the learning of such skills but are unlikely to make their best contribution unless organisations acknowledge learning as a mainstream activity, giving more thought to their long range development strategies, evolving suitable ‘learning climates’ and encouraging their managers to take a greater measure of responsibility for their own development. On the basis of this research we concluded that the contribution of the management development practitioner should be more variable than has usually been the case. His role, like that of the manager, should be largely determined by the situation and he should be responsive to the particular needs of organisations and individual managers. The research supports the argument for greater emphasis on the relationship between managerial action and learning and suggests that the methods used should be more carefully selected to suit individual managers' learning styles and development objectives.
The problem of rotating a single large mass through a given angular distance so that the performance shall meet given specifications is considered. Initially it is assumed…
The problem of rotating a single large mass through a given angular distance so that the performance shall meet given specifications is considered. Initially it is assumed that the general nature of the torque which can be applied is prescribed, but that certain parameters are at our disposal; the practical determination of the best values of the parameters is considered. For the analogous electrical problem, this is equivalent to determining the best values of certain resistances, capacitances and inductances in a given network containing variable elements. But in order to solve the problem it is more effective to make alterations and additions to the network, so that it becomes equivalent to one having the required performance, and the way in which this can be achieved for the single rotating mass is discussed. The restriction to a single‐mass system is merely for convenience and simplicity; the procedure here discussed is perfectly general.