Method and means for helium/hydrogen ratio measurement by alpha scattering

An apparatus for determining helium to hydrogen ratios in a gaseous sample is presented. The sample is bombarded with alpha particles created by a self contained radioactive source and scattering products falling within a predetermined forward scattering angular range impact a detector assembly. Two detectors are mounted in tandem, the first completely blocking the second with respect to incident scattering products. Alpha particle/hydrogen or alpha particle/helium collisions are identified by whether scattering product impacts occur simultaneously in both detectors or only in the first detector. Relative magnitudes of the two pulses can be used to further discriminate against other effects such as noise and cosmic ray events

Extraordinary Emergencies: Reproducing Moral Discourses of the Child in Institutional Interaction

This report uses audio recorded telephone calls and textual data from an emergency medical services call center to examine the interactional practices through which speakers produce what we call “extraordinary emergencies”, treating the events concerned as requiring moral, as well as medical, attention. Since one of the overarching institutional aims of emergency call centers is to facilitate the efficient provision of medical services, call-takers typically treat reported emergencies as routine events. However, in some instances speakers produce practices that do not contribute toward the institutional agenda of providing medical assistance, thereby treating them as extraordinary cases. These practices occurred recurrently in calls involving reports of emergencies relating to child sexuality, including sexual assaults against children and obstetric emergencies where the mother was particularly young. We discuss the implications of these findings for the situated reproduction of particular moral norms, especially with respect to the category of the child in society

Problems in determining sea surface topography

Anticipated problems for determining ocean dynamics signals from sea surface topography are discussed. The needs for repeated tracks are listed if oceanic tides or ocean turbulence are to be determined

Preliminary analysis of the span-distributed-load concept for cargo aircraft design

A simplified computer analysis of the span-distributed-load airplane (in which payload is placed within the wing structure) has shown that the span-distributed-load concept has high potential for application to future air cargo transport design. Significant increases in payload fraction over current wide-bodied freighters are shown for gross weights in excess of 0.5 Gg (1,000,000 lb). A cruise-matching calculation shows that the trend toward higher aspect ratio improves overall efficiency; that is, less thrust and fuel are required. The optimal aspect ratio probably is not determined by structural limitations. Terminal-area constraints and increasing design-payload density, however, tend to limit aspect ratio

Technical and Economic Evaluation of Advanced Air Cargo Systems

The current air cargo environment and the relevance of advanced technology aircraft in enhancing the efficiency of the 1990 air cargo system are discussed. NASA preliminary design studies are shown to indicate significant potential gains in aircraft efficiency and operational economics for future freighter concepts. Required research and technology elements are outlined to develop a better base for evaluating advanced design concepts. Current studies of the market operation are reviewed which will develop design criteria for a future dedicated cargo transport. Design features desirable in an all-freighter design are reviewed. NASA-sponsored studies of large, distributed-load freighters are reviewed and these designs are compared to current wide-body aircraft. These concepts vary in gross takeoff weight from 0.5 Gg (one million lbs.) to 1.5 Gg (three million lbs.) and are found to exhibit economic advantages over conventional design concepts

The promise of air cargo: System aspects and vehicle design

The current operation of the air cargo system is reviewed. An assessment of the future of air cargo is provided by: (1) analyzing statistics and trends, (2) by noting system problems and inefficiencies, (3) by analyzing characteristics of 'air eligible' commodities, and (4) by showing the promise of new technology for future cargo aircraft with significant improvements in costs and efficiency. The following topics are discussed: (1) air cargo demand forecasts; (2) economics of air cargo transport; (3) the integrated air cargo system; (4) evolution of airfreighter design; and (5) the span distributed load concept

Characteristics of future air cargo demand and impact on aircraft development: A report on the Cargo/Logistic Airlift Systems Study (CLASS) project

Current domestic and international air cargo operations are studied and the characteristics of 1990 air cargo demand are postulated from surveys conducted at airports and with shippers, consignees, and freight forwarders as well as air, land, and ocean carriers. Simulation and route optimization programs are exercised to evaluate advanced aircraft concepts. The results show that proposed changes in the infrastructure and improved cargo loading efficiencies are as important enhancing the prospects of air cargo growth as is the advent of advanced freighter aircraft. Potential reductions in aircraft direct operating costs are estimated and related to future total revenue. Service and cost elasticities are established and utilized to estimate future potential tariff reductions that may be realized through direct and indirect operating cost reductions and economies of scale

Preliminary analysis of hub and spoke air freight distribution system

A brief analysis is made of the hub and spoke air freight distribution system which would employ less than 15 hub centers world wide with very large advanced distributed-load freighters providing the line-haul delivery between hubs. This system is compared to a more conventional network using conventionally-designed long-haul freighters which travel between numerous major airports. The analysis calculates all of the transportation costs, including handling charges and pickup and delivery costs. The results show that the economics of the hub/spoke system are severely compromised by the extensive use of feeder aircraft to deliver cargo into and from the large freighter terminals. Not only are the higher costs for the smaller feeder airplanes disadvantageous, but their use implies an additional exchange of cargo between modes compared to truck delivery. The conventional system uses far fewer feeder airplanes, and in many cases, none at all. When feeder aircraft are eliminated from the hub/spoke system, however, that system is universally more economical than any conventional system employing smaller line-haul aircraft

Referring to Somebody:Generic Person Reference as an Interactional Resource

A growing body of research, examining a wide spectrum of reference forms across diverse languages, cultures, and identities, has shown how references to persons can be selected for context-specific interactional outcomes. This report describes how even such simple forms of person reference as somebody (along with someone and a/the person) can be selected on the basis of their relevance for the specific interactional context in which they are employed. We consider how the particular circumstances of some person reference occasions can make these generic person reference forms specially relevant (even when other, more elaborated forms of reference, either recognitional or non-recognitional, were evidently available to the speaker), and we demonstrate how even these barest forms of person reference can be called on to perform delicate, context-sensitive interactional work. Specifically, we show that speakers can select these generic reference forms for non-recognitional references that a) contribute to the formation of the action of a turn, and, when used in a story, b) contribute to the story’s telling. Finally, we show how a generic person reference can be selected in place of a recognitional reference, thereby openly concealing a referent’s identity