231 research outputs found
Application of NASA ERTS-1 satellite imagery in coastal studies
There are no author-identified significant results in this report. Review of ERTS-1 imagery indicates that it contains information of great value in coastal engineering studies. A brief introduction is given to the methods by which imagery is generated, and examples of its application to coastal engineering. Specific applications discussed include study of the movement of coastal and nearshore sediment-laden water masses and information for planning and construction in remote areas of the world
Application of ERTS-1 imagery in coastal studies
The basic ERTS output is four black-and-white photographs presenting the same scene recorded in each multispectral scanner band. Mosaics covering large regions at a 1:250,000 scale can be compiled from these photographs. Office study of the image of each band separately, in combination with other bands, and in conjunction with other available data (navigation charts, tide tables, etc.) permits extraction of data useful in coastal engineering planning and coastal processes studies. Specific examples in which significant information on regional shoreline configuration or nearshore water movements has been obtained from unenhanced ERTS imagery are: (1) tidal inlet configuration; (2) navigation information; and (3) nearshore water movements
Sediment Quality in Puget Sound Year 3 - Southern Puget Sound
As a component of a three-year cooperative effort of the Washington State Department of Ecology and the National Oceanic and Atmospheric Administration, surficial sediment samples from 100 locations in southern Puget Sound were collected in 1999 to determine their relative quality based on measures of toxicity, chemical contamination, and benthic infaunal assemblage structure. The survey
encompassed an area of approximately 858 km2, ranging from East and Colvos Passages south to Oakland Bay, and including Hood Canal. Toxic responses were most severe in some of the industrialized waterways of Tacoma’s Commencement Bay. Other industrialized harbors in which
sediments induced toxic responses on smaller scales included the Port of Olympia, Oakland Bay at Shelton, Gig Harbor, Port Ludlow, and Port Gamble. Based on the methods selected for this survey, the spatial extent of toxicity for the southern Puget Sound survey area was 0% of the total survey area for amphipod survival, 5.7% for urchin fertilization, 0.2% for microbial bioluminescence, and 5-
38% with the cytochrome P450 HRGS assay. Measurements of trace metals, PAHs, PCBs, chlorinated pesticides, other organic chemicals, and other characteristics of the sediments, indicated that 20 of the 100 samples collected had one or more chemical concentrations that exceeded
applicable, effects-based sediment guidelines and/or Washington State standards. Chemical contamination was highest in eight samples collected in or near the industrialized waterways of Commencement Bay. Samples from the Thea Foss and Middle Waterways were primarily
contaminated with a mixture of PAHs and trace metals, whereas those from Hylebos Waterway were contaminated with chlorinated organic hydrocarbons. The remaining 12 samples with elevated chemical concentrations primarily had high levels of other chemicals, including bis(2-ethylhexyl)
phthalate, benzoic acid, benzyl alcohol, and phenol. The characteristics of benthic infaunal assemblages in south Puget Sound differed considerably among locations and habitat types throughout the study area. In general, many of the small embayments and inlets throughout the study
area had infaunal assemblages with relatively low total abundance, taxa richness, evenness, and dominance values, although total abundance values were very high in some cases, typically due to high abundance of one organism such as the polychaete Aphelochaeta sp. N1. The majority of the
samples collected from passages, outer embayments, and larger bodies of water tended to have infaunal assemblages with higher total abundance, taxa richness, evenness, and dominance values. Two samples collected in the Port of Olympia near a superfund cleanup site had no living organisms in them. A weight-of-evidence approach used to simultaneously examine all three “sediment quality
triad” parameters, identified 11 stations (representing 4.4 km2, 0.5% of the total study area) with sediment toxicity, chemical contamination, and altered benthos (i.e., degraded sediment quality), 36 stations (493.5 km2, 57.5% total study area) with no toxicity or chemical contamination (i.e., high sediment quality), 35 stations (274.1 km2, 32.0% total study area) with one impaired sediment triad
parameter (i.e., intermediate/high sediment quality), and 18 stations (85.7km2, 10.0% total study area) with two impaired sediment parameters (i.e., intermediate/degraded quality sediments). Generally, upon comparison, the number of stations with degraded sediments based upon the sediment quality triad of data was slightly greater in the central Puget Sound than in the northern and southern Puget Sound study areas, with the percent of the total study area degraded in each region decreasing from central to north to south (2.8, 1.3 and 0.5%, respectively). Overall, the sediments collected in Puget Sound during the combined 1997-1999 surveys were among the least contaminated relative to other marine bays and estuaries studied by NOAA using equivalent methods. (PDF contains 351 pages
Cryogenic optical beam steering for superconducting device calibration
We have developed a calibration system based on a micro-electromechanical
systems (MEMS) mirror that is capable of delivering an optical beam over a
wavelength range of 180 -- 2000 nm (0.62 -- 6.89 eV) in a sub-Kelvin
environment. This portable, integrated system can steer the beam over a 3
cm 3 cm area on the surface of any sensor with a precision of
100 m, enabling characterization of device response as a function of
position. This fills a critical need in the landscape of calibration tools for
sub-Kelvin devices, including those used for dark matter detection and quantum
computing. These communities have a shared goal of understanding the impact of
ionizing radiation on device performance, which can be pursued with our system.
This paper describes the design of the first-generation calibration system and
the results from successfully testing its performance at room temperature and
20 mK.Comment: 17 pages, 7 figures, submitted to SPI
Use of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurements
The environments in which we live, work, and play are subject to
enormous variability in air pollutant concentrations. To adequately
characterize air quality (AQ), measurements must be fast (real time), scalable,
and reliable (with known accuracy, precision, and stability over time).
Lower-cost air-quality-sensor technologies offer new opportunities for
fast and distributed measurements, but a persistent characterization gap
remains when it comes to evaluating sensor performance under realistic
environmental sampling conditions. This limits our ability to inform the
public about pollution sources and inspire policy makers to address
environmental justice issues related to air quality. In this paper, initial
results obtained with a recently developed lower-cost air-quality-sensor
system are reported. In this project, data were acquired with the ARISense
integrated sensor package over a 4.5-month time interval during which the
sensor system was co-located with a state-operated (Massachusetts, USA) air
quality monitoring station equipped with reference instrumentation measuring
the same pollutant species. This paper focuses on validating electrochemical
(EC) sensor measurements of CO, NO, NO2, and O3 at an urban neighborhood
site with pollutant concentration ranges (parts per billion by volume, ppb; 5 min averages, ±1σ):
[CO] = 231 ± 116 ppb (spanning 84–1706 ppb),
[NO] = 6.1 ± 11.5 ppb (spanning 0–209 ppb),
[NO2] = 11.7 ± 8.3 ppb (spanning 0–71 ppb), and
[O3] = 23.2 ± 12.5 ppb (spanning 0–99 ppb). Through
the use of high-dimensional model representation (HDMR), we show that
interference effects derived from the variable ambient gas concentration mix
and changing environmental conditions over three seasons (sensor flow-cell
temperature = 23.4 ± 8.5 °C,
spanning 4.1 to
45.2 °C; and
relative humidity = 50.1 ± 15.3 %, spanning
9.8–79.9 %) can be effectively modeled for the Alphasense CO-B4,
NO-B4, NO2-B43F, and Ox-B421 sensors, yielding (5 min average) root mean
square errors (RMSE) of 39.2, 4.52, 4.56, and 9.71 ppb, respectively. Our
results substantiate the potential for distributed air pollution measurements
that could be enabled with these sensors
"I am becoming more and more like my eldest brother!": the relationship between older siblings, adolescent gambling severity, and the attenuating role of parents in a large-scale nationally representative survey study
The present study examined the association between having older siblings who gamble and adolescent at-risk/problem gambling and how parents (i.e., parental knowledge of their whereabouts) and peers might moderate such effects. Data were drawn from the ESPAD®Italia2012 survey (European School Survey Project on Alcohol and Other Drugs) comprising a nationally representative Italian sample of adolescents. The analysis was carried out on a subsample of 10,063 Italian students aged 15–19 years (average age = 17.10; 55 % girls) who had at least one older sibling and who had gambled at some point in their lives. Respondents’ problem gambling severity, older gambler sibling, gambler peers, parental knowledge, and socio-demographic characteristics were individually assessed. Multinomial logistic regression analyses including two- and three-way interactions were conducted. The odds of being an at-risk/problem gambler were higher among high school students with older siblings that gambled and those with peers who gambled. Higher parental knowledge (of who the adolescent was with and where they were in their leisure time) was associated with lower rates of at-risk/problem gambling. There was also an interaction between gamblers with older siblings and parental knowledge. The combination of having siblings who gambled and a greater level of parental knowledge was associated with lower levels of problem gambling. The present study confirmed the occurrence of social risk processes (older siblings and peers who gambled) and demonstrated that gambling among older siblings and peers represents an important contextual factor for increased at-risk/problem gambling. However, parental knowledge appears to be sufficient to counterbalance the influence of older siblings
Factors that influence children's gambling attitudes and consumption intentions: Lessons for gambling harm prevention research, policies and advocacy strategies
Background: Harmful gambling is a public health issue that affects not only adults but also children. With the development of a range of new gambling products, and the marketing for these products, children are potentially exposed to gambling more than ever before. While there have been many calls to develop strategies which protect children from harmful gambling products, very little is known about the factors that may influence children's attitudes towards these products. This study aimed to explore children's gambling attitudes and consumption intentions and the range of consumer socialisation factors that may influence these attitudes and behaviours. Methods: Children aged 8 to 16 years old (n = 48) were interviewed in Melbourne, Australia. A semi-structured interview format included activities with children and open-ended questions. We explored children's perceptions of the popularity of different gambling products, their current engagement with gambling, and their future gambling consumption intentions. We used thematic analysis to explore children's narratives with a focus on the range of socialising factors that may shape children's gambling attitudes and perceptions. Results: Three key themes emerged from the data. First, children's perceptions of the popularity of different products were shaped by what they had seen or heard about these products, whether through family activities, the media (and in particular marketing) of gambling products, and/or the alignment of gambling products with sport. Second, children's gambling behaviours were influenced by family members and culturally valued events. Third, many children indicated consumption intentions towards sports betting. This was due to four key factors: (1) the alignment of gambling with culturally valued activities; (2) their perceived knowledge about sport; (3) the marketing and advertising of gambling products (and in particular sports betting); and (4) the influence of friends and family. Conclusions: This study indicates that there is a range of socialisation factors, particularly family and the media (predominantly via marketing), which may be positively shaping children's gambling attitudes, behaviours and consumption intentions. There is a need for governments to develop effective policies and regulations to reduce children's exposure to gambling products and ensure they are protected from the harms associated with gambling. © 2017 The Author(s)
- …