Problems of Excess Capacity

The problems of excess capacity in the airline industry are discussed with focus on the following topics: load factors; fair rate of return on investment; service-quality rivalry among airlines; pricing (fare) policies; aircraft production; and the impacts of excess capacity on operating costs. Also included is a discussion of the interrelationships among these topics

What may be learnt about the archaeology of islands from archaeologically derived models of the exploration of Polynesia, 1966-2001?

Polynesian archaeology is one regional specialization in the world-wide practice of archaeological investigations of islands, oceans and seas. It is timely to consider how Polynesian archaeology fits within that newly-articulated framework of theoretical and methodological advances concerned with islands. To do this, I examine the history of archaeologically-derived models of the exploration of Polynesia developed since the invention of radiocarbon dating

Beauty (Essay 8 of Seeing: When Art and Faith Intersect)

Excerpt: Beauty as a concept has given twentieth century writers, especially art critics and art historians, a great deal of difficulty. Why is this so?Answering would take several volumes--! will settle for less. The traditional idea of beauty has all the trappings of a universal concept. For Plato, one of the earliest and most prominent supporters of such universals, beauty, along with other concepts, had the mind of the creator as its source. For much of Christianity\u27s existence Plato\u27s idea of beauty was accepted--with some alterations. For one, the creator became Yahweh, creator of the universe. Secondly, though spiritual beauty might inhabit physical beauty, the reverse was not necessarily the case

Local, hierarchic, and iterative reconstructors for adaptive optics

Adaptive optics systems for future large optical telescopes may require thousands of sensors and actuators. Optimal reconstruction of phase errors using relative measurements requires feedback from every sensor to each actuator, resulting in computational scaling for n actuators of n^2 . The optimum local reconstructor is investigated, wherein each actuator command depends only on sensor information in a neighboring region. The resulting performance degradation on global modes is quantified analytically, and two approaches are considered for recovering "global" performance. Combining local and global estimators in a two-layer hierarchic architecture yields computations scaling with n^4/3 ; extending this approach to multiple layers yields linear scaling. An alternative approach that maintains a local structure is to allow actuator commands to depend on both local sensors and prior local estimates. This iterative approach is equivalent to a temporal low-pass filter on global information and gives a scaling of n^3/2 . The algorithms are simulated by using data from the Palomar Observatory adaptive optics system. The analysis is general enough to also be applicable to active optics or other systems with many sensors and actuators

Socio-economic aspects of cigarette smoking in Malta and Gozo

Questions on smoking behaviour were included in the Census of Population and Housing taken in November 1985. Information was gathered on the number of cigarettes consumed by smokers, those who had stopped smoking and those who had never smoked. Since the Census, smoking has figured prominently in Maltese newspapers and the Health Education unit has been active in publicising the health hazards associated with tobacco dependence. Nevertheless relatively little research has been done on patterns of cigarette smoking and on the demographic, socio-economic and environmental factors that may go some way towards explaining the sharp variations in cigarette addiction within Malta and Gozo. This paper explores a number of these underlying dimensions and using a simple statistical index identifies those neighbourhoods which have high, about average and low levels of smoking behaviour.peer-reviewe