1,467 research outputs found
Haze in the Mars atmosphere as revealed by the Mariner 4 television data
Photometric investigation of haze in Mars atmosphere revealed by Mariner 4 television dat
Fixed point adjunctions for module spectra
We consider the Quillen adjunction between fixed points and inflation in the context of equivariant module spectra over equivariant ring spectra, and give numerous examples including some based on geometric fixed points and some on the Eilenberg-Moore spectral sequence. These results were originally presented as part of our equivalence between rational torus-equivariant spectra and an algebraic model in arXiv:1101.2511. However, the present results apply in many other interesting cases explored here, which are not rational and where the ambient group is not a torus. The material in arXiv:1101.2511v3 will be revised to refer to this paper
Spatial Sampling Strategies with Multiple Scientific Frames of Reference
We study the spatial sampling strategies employed by field scientists studying aeolian processes, which are geophysical interactions between wind and terrain. As in geophysical field science in general, observations of aeolian processes are made and data gathered by carrying instruments to various locations and then deciding when and where to record a measurement. We focus on this decision-making process. Because sampling is physically laborious and time consuming, scientists often develop sampling plans in advance of deployment, i.e., employ an offline decision-making process. However, because of the unpredictable nature of field conditions, sampling strategies generally have to be updated online. By studying data from a large field deployment, we show that the offline strategies often consist of sampling along linear segments of physical space, called transects. We proceed by studying the sampling pattern on individual transects. For a given transect, we formulate model-based hypotheses that the scientists may be testing and derive sampling strategies that result in optimal hypothesis tests. Different underlying models lead to qualitatively different optimal sampling behavior. There is a clear mismatch between our first optimal sampling strategy and observed behavior, leading us to conjecture about other, more sophisticated hypothesis tests that may be driving expert decision-making behavior.
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SISTEM REKOMENDASI PARIWISATA PANTAI MENGGUNAKAN METODE CONTENT BASED FILTERING
Negara Indonesia memiliki potensi alam yang sangat indah dengan budaya dan adat istiadat yang melimpah dan melekat erat sebagai jati diri bangsa dan dipegang teguh oleh masyarakat Indonesia yang belum tentu dimiliki oleh negara lain. Daya tarik yang dimiliki Negara Indonesia yaitu pemandangan alam yang indah dan beraneka ragam ditunjang dengan sikap masyarakat yang memegang teguh adat Indonesia yang terkenal dengan ramah tamah menjadikan Indonesia sebagai salah satu tempat wisata yang mampu menarik wisatawan baik domestik maupun asing untuk berkunjung ke Indonesia. Salah satu tempat wisata yang menjadi favorit adalah pantai. Hal ini juga didukung dengan banyaknya pengunjung beberapa pantai terkenal di Pulau Jawa, seperti Pantai Parangtritis pada tahun 2011 sebanyak 1,338.112 wisatawan, Pantai Pangandaran pada tahun 2013 sebanyak wisatawan mancanegara sebanyak 8.587 orang dan wisatawan nusantara 1.552.153 orang, akan tetapi dari banyaknya pengunjung pantai tersebut masih terdapat pantai yang sepi, seperti Pantai Jambu di Banten, pantai ini tidak kalah indahnya dari pantai-pantai yang sudah terkenal di Pulau Jawa. Berdasarkan permasalahan yang dijelaskan diatas, metode Content Based Filtering diterapkan untuk membuat sistem rekomendasi pariwisata pantai yang dapat membantu wisatawan mendapatkan informasi pantai yang masih sepi dan indah. Pengujian precision dan recall menghasilkan nilai masing-masing 72% dan 19.23%. Kata kunci: Text Proccesing, Vector Space Model, Cosine Similarity, Content Based Filtering
Reaction time and incident cancer: 25 years of follow-up of study members in the UK Health and Lifestyle Survey
<b>Objectives</b><p></p>
To investigate the association of reaction time with cancer incidence.<p></p>
<b>Methods</b><p></p>
6900 individuals aged 18 to 94 years who participated in the UK Health and Lifestyle Survey in 1984/1985 and were followed for a cancer registration for 25 years.<p></p>
<b>Results</b><p></p>
Disease surveillance gave rise to 1015 cancer events from all sites. In general, there was essentially no clear pattern of association for either simple or choice reaction time with cancer of all sites combined, nor specific malignancies. However, selected associations were found for lung cancer, colorectal cancer and skin cancer.<p></p>
<b>Conclusions</b><p></p>
In the present study, reaction time and its components were not generally related to cancer risk
Lunar surface mechanical properties â Surveyor 1
Engineering telemetry data and lunar surface photographs by Surveyor 1 have been evaluated for information on the mechanical properties of the lunar surface material at the Surveyor 1 landing site. Based primarily on photographic evidence, estimates of soil density, cohesion, and other soil characteristics are presented. Also, the mechanisms in which the lunar material is believed to have failed under the footpad impacts are discussed. Because dynamic soil reactions cannot be interpreted directly from the available data, a comparative study using computer-simulated landings was initiated. Preliminary results of this study, which is still in progress, are presented
HFF-DeepSpace photometric catalogs of the 12 Hubble frontier fields, clusters, and parallels : photometry, photometric redshifts, and stellar masses
We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have constructed homogeneous photometric catalogs for all six clusters and their parallels. To further expand these data catalogs, we have added ultra-deep KS-band imaging at 2.2. mu m from the Very Large Telescope HAWK-I and Keck-I MOSFIRE instruments. We also add post-cryogenic Spitzer imaging at 3.6 and 4.5. mu m with the Infrared Array Camera (IRAC), as well as archival IRAC 5.8 and 8.0. mu m imaging when available. We introduce the public release of the multi-wavelength (0.2-8 mu m) photometric catalogs, and we describe the unique steps applied for the construction of these catalogs. Particular emphasis is given to the source detection band, the contamination of light from the bright cluster galaxies (bCGs), and intra-cluster light (ICL). In addition to the photometric catalogs, we provide catalogs of photometric redshifts and stellar population properties. Furthermore, this includes all the images used in the construction of the catalogs, including the combined models of bCGs and ICL, the residual images, segmentation maps, and more. These catalogs are a robust data set of the Hubble Frontier Fields and will be an important aid in designing future surveys, as well as planning follow-up programs with current and future observatories to answer key questions remaining about first light, reionization, the assembly of galaxies, and many more topics, most notably by identifying high-redshift sources to target
Robotic Measurement of Aeolian Processes
Measurements used to study wind shear stress and turbulence, surface roughness, sand flux, and dust emissions are typically obtained from stationary instrumentation, and are thus limited spatially. They are also dependent on deployment of instrumentation for specific events and thus the are limited temporally. We have been adapting a rough-terrain legged robot capable of rapidly traversing desert terrain to serve as a semi-autonomous, reactive mobile sensory platform (RHex [1]), which would not share these limitations. We report on early trials of the robotic platform at the Jornada LTER and White Sands National Monument to test the feasibility of gathering measurements of airflow and rates of particle transport on a dune, assessing the role of roughness elements such as vegetation in modifying the wind shear stresses incident on the surface, and estimating erosion susceptibility in an arid soil. The robot not only serves as a mobile platform for science instruments; it can also perform controlled âkick testsâ to locally examine soil strength. We outline a strategy for mapping soil erodibility and its controlling parameters using the unique capabilities of RHex, and the implications for understanding erosion and dust emission from complex terrain
Degree of explanation
Partial explanations are everywhere. That is, explanations citing causes that explain some but not all of an effect are ubiquitous across science, and these in turn rely on the notion of degree of explanation. I argue that current accounts are seriously deficient. In particular, they do not incorporate adequately the way in which a causeâs explanatory importance varies with choice of explanandum. Using influential recent contrastive theories, I develop quantitative definitions that remedy this lacuna, and relate it to existing measures of degree of causation. Among other things, this reveals the precise role here of chance, as well as bearing on the relation between causal explanation and causation itself
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What will the cardiovascular disease slowdown cost? Modelling the impact of CVD trends on dementia, disability, and economic costs in England and Wales from 2020-2029.
To model the health impact and economic costs of the recent slowing of the historical decline in cardiovascular disease (CVD) incidence
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