David B. Harris

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In Xuan Wei County, Yunnan Province, lung cancer mortality is among China's highest and, especially in females, is more closely associated with indoor burning of "smoky" coal, as opposed to wood or "smokeless" coal, than with tobacco smoking. Indoor air samples were collected during the burning of all three fuels. In contrast to wood and smokeless coal(More)
A nontrivial portion of heavy-duty vehicle emissions of NOx and particulate matter (PM) occurs during idling. Regulators and the environmental community are interested in curtailing truck idling emissions, but current emissions models do not characterize them accurately, and little quantitative data exist to evaluate the relative effectiveness of various(More)
W To develop sampling strategies and bioassay protocols for indoor air containing emissions from coal combustion in homes of the rural Xuan Wei County in China, we developed a medium-volume sampler to collect the <lO-pm particles and semivolatile organics by a filter and an XADS resin, respectively. A high-volume particulate sampler was used for comparison.(More)
Recursive Least Squares (RLS) algorithms have wide-spread applications in many areas, such as real-time signal processing, control and communications. This paper shows that the unique solutions to linear-equality constrained and the unconstrained LS problems, respectively, always have exactly the same recursive form. Their only difference lies in the(More)
To develop effective air quality control strategies for military air bases, there is a need to accurately quantify these emissions. In support of the Strategic Environmental Research and Development Program project, the particulate matter (PM) and gaseous emissions from two T56 engines on a parked C-130 aircraft were characterized at the Kentucky Air(More)
In Xuan Wei, a rural Chinese county of about one million people, females' annual lung cancer mortality is China's highest, and males' is among China's highest. Xuan Wei's very high indoor air pollution levels (sometimes exceeding 20 mg/m3), residentially stable population, relatively uncomplicated lifestyle, and wide geographic variation in lung cancer(More)
We continue exploring methodologies to improve earthquake-explosion discrimination using regional amplitude ratios such as P/S (ratio of Pand/or S-wave energy). The earliest simple source models predicted P/S wave amplitudes for explosions should be much larger than for earthquakes across the body wave spectrum. However empirical observations show the(More)
Originally constructed to develop gaseous emission factors for heavy-duty diesel trucks, the U.S. Environmental Protection Agency's (EPA) On-Road Diesel Emissions Characterization Facility has been modified to incorporate particle measurement instrumentation. An electrical low-pressure impactor designed to continuously measure and record size distribution(More)
An auto-positioning open-path Fourier Transform Infrared (FTIR) spectrometer can be used to directly measure vertical concentration profiles in a plume downwind from an emission source. The multi-component analysis capabilities of FTIR spectroscopy allow simultaneous measurement of diverse downwind pollutant species. Using concentration measurements and(More)