22,755 research outputs found
INTEGRATED ASSESSMENT AND MANAGEMENT OF WATER QUANTITY AND WATER QUALITY IN THE MERRIMACK RIVER BASIN, NEW HAMPSHIRE
Neighborhood Crime and Transit Station Access Mode choice - Phase III of Neighborhood Crime and Travel Behavior
This report provides the findings from the third phase of a three-part study about the influences of neighborhood crimes on travel mode choice. While previous phases found evidence that high levels of neighborhood crime discourage people from choosing to walk, bicycle and ride transit, consistent with the authorsâ hypothesis, they also produced counterintuitive findings suggesting that in some cases, high crime neighborhoods encourage transit ridership at the expense of drivingâthe opposite of what common sense would suggest. Phase 3 tested possible explanations for these counterintuitive findings with a series of methodological improvements. These improvements were: Improvement 1: Used the Bay Area Rapid Transit (BART) systemâs 2008 Station Profile Survey travel data set to replace the Bay Area Travel Survey (BATS) 2000 data used in previous phases. Improvement 2: Separated drop-off and drive-alone modes in logit models. Improvement 3: Variables at the corridor level replaced previous variables at the transportation analysis zone (TAZ) level. Improvement 4: Average parcel size (APS) variable replaced the intersection density measure of urban design. Improvement 5: Used nested logit modeling techniques.
These yielded strong evidence supporting the hypothesis that high-crime neighborhoods encourage driving, and they generated none of the counterintuitive findings from previous phases
Synthesis and Characterization of Mixed Methyl/Allyl Monolayers on Si(111)
The formation of mixed methyl/allyl monolayers has been accomplished through a two-step halogenation/alkylation reaction on Si(111) surfaces. The total coverage of alkylated Si, the surface recombination velocities, and the degree of surface oxidation as a function of time have been investigated using X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and microwave conductivity measurements. The total coverage of alkyl groups, the rate of oxidation, and the surface recombination velocities of Si(111) terminated by mixed monolayers were found to be close to those observed for CH_3âSi(111) surfaces. Hence, the mixed-monolayer surfaces retained the beneficial properties of CH_3âSi(111) surfaces while allowing for convenient secondary surface functionalization
A Next Generation High-speed Data Acquisition System for Multi-channel Infrared and Optical Photometry
We report the design, operation, and performance of a next generation
high-speed data acquisition system for multi-channel infrared and optical
photometry based on the modern technologies of Field Programmable Gate Arrays,
the Peripheral Component Interconnect bus, and the Global Positioning System.
This system allows either direct recording of photon arrival times or binned
photon counting with time resolution up to 1-s precision in Universal
Time, as well as real-time data monitoring and analysis. The system also allows
simultaneous recording of multi-channel observations with very flexible,
reconfigurable observational modes. We present successful 20-s resolution
simultaneous observations of the Crab Nebula Pulsar in the infrared (H-band)
and optical (V-band) wavebands obtained with this system and 100-s
resolution V-band observations of the dwarf nova IY Uma with the 5-m Hale
telescope at the Palomar Observatory.Comment: 11 pages, including 4 figures, to appear in PAS
Local Labor Market Conditions and the Jobless Poor: How Much Does Local Job Growth Help in Rural Areas?
The employment outcomes of a group of jobless poor Oregonians are tracked in order to analyze the relative importance of local labor market conditions on their employment outcomes. Local job growth increases the probability that a jobless poor adult will get a job and shortens the length of time until she finds a job. After accounting for both the effects of personal demographic characteristics and local job growth, there is little evidence that the probability of employment or the duration of joblessness differs in rural compared with urban areas.employment, local labor markets, rural labor markets, rural poverty, unemployment, welfare reform, Labor and Human Capital,
EMPLOYMENT OUTCOMES FOR LOW-INCOME ADULTS IN RURAL AND URBAN LABOR MARKETS
This study analyzes the impact of local labor market conditions on the probability of employment and duration of employment for low-income adults in Oregon. We find that economic conditions (lower employment growth and higher unemployment rates) help to explain the less successful employment outcomes for low-income adults in non-metro areas.rural labor markets, employment, low-income workers, Labor and Human Capital,
A Discontinuity in the Distribution of Fixed Point Sums
The quantity , defined as the number of permutations of the set
whose fixed points sum to , shows a sharp discontinuity
in the neighborhood of . We explain this discontinuity and study the
possible existence of other discontinuities in for permutations. We
generalize our results to other families of structures that exhibit the same
kind of discontinuities, by studying when ``fixed points'' is replaced
by ``components of size 1'' in a suitable graph of the structure. Among the
objects considered are permutations, all functions and set partitions.Comment: 1 figur
Crystallization and preliminary diffraction studies of morphinone reductase, a flavoprotein involved in the degradation of morphine alkaloids
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