Lead as a tracer for automotive particulates: projecting the sulfate air quality impact of oxidation catalyst-equipped cars in Los Angeles

An analysis of the fate of lead in the Los Angeles Basin is used to evaluate an emissions to air quality model for automotive exhaust particulates. The dispersion model is then applied to projecting the annual average sulfate air quality impact of direct sulfuric acid mist emissions from oxidation catalyst-equipped cars of the 1975 model type. Estimates are given of the incremental sulfate contributions from three model years of oxidation catalyst-equipped cars burning a relatively low sulfur gasoline, and from roughly ten model years of 1975-type autos burning gasoline of sulfur content equal to that of the entire 1974 Southern California gasoline pool. In the latter case, sulfate concentrations in portions of downtown Los Angeles in 1985 could be elevated by roughly two thirds above present average sulfate values

Cost and Performance of Automotive Emission Control Technologies

The problem at hand is to investigate the near-term commercial feasibility of a wide range of automotive emission control technologies. The central issues can best be explained in terms of the emission control characteristics of each technology and their costs. Governmentally established emission control standards may be viewed as constraints on the use of a given vehicle and engine design. Either the technology meets the standard in use or it will not be sold. Emission control technologies that show promise of near-term manufacturability will be identified. Then, without presuming what future emission standards will be, the emission characteristics of example vehicle-engine combinations will be listed. Technologies that are acceptable, given a specified emission standard, can then be identified by a process of elimination. The approach to identifying the relevant costs associated with a given technology is not as clear cut. One would like to think that the most basic question governing the adoption of a given feasible technology is, "Will it be purchased by the public?" The second part of this paper will discuss the impact of pollution control technology on the economic decisions facing the new car customer. The cost considered by the rational new car consumer involves more than first cost. Other important factors include maintenance, operating expenses, resale value, and financing charges. Since resale value and financing charges are highly time dependent, it is possible that a new car purchaser's decision on which technology to buy may depend on how long he plans to keep the car. A cost annualization procedure will thus be developed which considers these factors

Systems integrated human engineering on the Navy's rapid acquisition of manufactured parts/test and integration facility

Human Engineering in many projects is at best a limited support function. In this Navy project the Human Engineering function is an integral component of the systems design and development process. Human Engineering is a member of the systems design organization. This ensures that people considerations are: (1) identified early in the project; (2) accounted for in the specifications; (3) incorporated into the design; and (4) the tested product meets the needs and expectations of the people while meeting the overall systems requirements. The project exemplifies achievements that can be made by the symbiosis between systems designers, engineers and Human Engineering. This approach increases Human Engineering's effectiveness and value to a project because it becomes an accepted, contributing team member. It is an approach to doing Human Engineering that should be considered for most projects. The functional and organizational issues giving this approach strength are described

Gender and the Influence of Peer Alcohol Consumption on Adolescent Sexual Activity

I consider the alcohol consumption of opposite-gender peers as explanatory to adolescent sexual intercourse and demonstrate that female sexual activity is higher where there is higher alcohol consumption among male peers. This relationship is robust to school fixed effects, cannot be explained by broader cohort effects or general anti-social behaviors in male peer groups, and is distinctly different from any influence of the alcohol consumption of female peers which is shown to have no influence on female sexual activity. There is no evidence that male sexual activity responds to female-peer alcohol consumption.peer, adolescent, alcohol, sex, risky behavior

Adolescent Drug Use and the Deterrent Effect of School-Imposed Penalties

Simple OLS estimates of the effect of school-imposed penalties for drug use on a student's consumption of marijuana are biased if both are determined by unobservable school or individual attributes. The potential reverse causality is also a challenge to retrieving estimates of the causal relationship, as the severity of school sanctions may simply reflect the need for more-severe sanctions. I offer an instrumental-variables approach to retrieving an estimate of the causal response of marijuana use to sanctions and thereby demonstrate the efficacy of school-imposed penalties as a deterrent to adolescent drug use. This is the first evidence of such efficacy and, given what is known about the consequences of drug use, suggests that school sanctions may have important long-run benefits.drug, crime, adolescent, risky behavior, expulsion

Design and Implementation of an Extensible Variable Resolution Bathymetric Estimator

For grid-based bathymetric estimation techniques, determining the right resolution at which to work is essential. Appropriate grid resolution can be related, roughly, to data density and thence to sonar characteristics, survey methodology, and depth. It is therefore variable in almost all survey scenarios, and methods of addressing this problem can have enormous impact on the correctness and efficiency of computational schemes of this kind. This paper describes the design and implementation of a bathymetric depth estimation algorithm that attempts to address this problem by combining the computational efficiency of locally regular grids with piecewise-variable estimation resolution to provide a single logical data structure and associated algorithms that can adjust to local data conditions, change resolution where required to best support the data, and operate over essentially arbitrarily large areas as a single unit. The algorithm, which is in part a development of CUBE, is modular and extensible, and is structured as a client-server application to support different implementation modalities. The algorithm is called “CUBE with Hierarchical Resolution Techniques”, or CHRT

TOMORROW IS TODAY

The author reviews the progress of materials handling techniques over the past quarter century and projects today's concepts against the requirements of the future, concluding with his evaluations of the changes that will take place in the years ahead.Industrial Organization,