930 resultados para Night and Day


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The chief challenge facing persistent robotic navigation using vision sensors is the recognition of previously visited locations under different lighting and illumination conditions. The majority of successful approaches to outdoor robot navigation use active sensors such as LIDAR, but the associated weight and power draw of these systems makes them unsuitable for widespread deployment on mobile robots. In this paper we investigate methods to combine representations for visible and long-wave infrared (LWIR) thermal images with time information to combat the time-of-day-based limitations of each sensing modality. We calculate appearance-based match likelihoods using the state-of-the-art FAB-MAP [1] algorithm to analyse loop closure detection reliability across different times of day. We present preliminary results on a dataset of 10 successive traverses of a combined urban-parkland environment, recorded in 2-hour intervals from before dawn to after dusk. Improved location recognition throughout an entire day is demonstrated using the combined system compared with methods which use visible or thermal sensing alone.

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Because dolphins sometimes travel with yellowfin tuna, Thunnus albacares, in the eastern tropical Pacific (ETP), purse seiners use the dolphins to locate and capture tuna schools. During the process of setting the purse seine nets, dolphins often become entangled and drown before they can be released. Data for the U.S. purse seine fleet in the ETP during 1979-88 show that dolphin mortality rates in sets made during the night are higher than mortality rates in sets made during the day. Even with efforts to reduce nightset mortality rates through the use of high intensity floodlights, night set mortality rates remain higher. The data are also used to simulate a regulation on the fishery aimed at eliminating night sets and show that dolphin mortality rates would decrease.

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The assembly of sarcomeric proteins into the highly organized structure of the sarcomere is an ordered and complex process involving an array of structural and associated proteins. The sarcomere has shown itself to be considerably more complex than ever envisaged and may be considered one of the most complex macromolecular assemblies in biology. Studies over the last decade have helped to put a new face on the sarcomere, and, as such, the sarcomere is being redefined as a dynamic network of proteins capable of generating force and signalling with other cellular compartments and metabolic enzymes capable of controlling many facets of striated myocyte biology.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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To test the association between night work and work ability, and verify whether the type of contractual employment has any influence over this association. Permanent workers (N = 642) and workers with precarious jobs (temporary contract or outsourced; N = 552) were interviewed and filled out questionnaires concerning work hours and work ability index. They were classified into: never worked at night, ex-night workers, currently working up to five nights, and currently working at least six nights/2-week span. After adjusting for socio-demography and work variables, current night work was significantly associated with inadequate WAI (vs. day work with no experience in night work) only for precarious workers (OR 2.00, CI 1.01-3.95 and OR 1.85, CI 1.09-3.13 for those working up to five nights and those working at least six nights in 2 weeks, respectively). Unequal opportunities at work and little experience in night work among precarious workers may explain their higher susceptibility to night work.

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Mode of access: Internet.

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Both traditional and progressive curricula are inadequate for the task of responding to the economic, political, social, and cultural changes that have occurred as a result of globalization. This book documents some of the ongoing work occurring in early childhood settings that is aimed at improving, and ultimately transforming, early childhood practice in these changed and changing times. The authors do not simply critique developmental approaches or the increasing standardization of the field. Instead, they describe how they are playing around with postmodern ideas in practice and developing unique approaches to the diverse educational circumstances that confront early childhood educators. Whether it is preparing teachers, using materials, or developing policies, each chapter provides readers with possibilities for enacting pedagogies that are responsive to the contemporary circumstances shaping the lives of young children.

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Technical: This looped video work is made up from a number of still images animated in a sequence, not intended to be a smooth action, but syncopated. The gaps in real time suggest blinking, lapses in technology, warps in time and distance. The still images have been manipulated in photoshop and imported into an animation software program, showing subtle emphasis on various aspects of the features of the face and location from the screen shots. Content: Obsession is one of the most constant expressions of love, whether it is a negative attribute, such as stalking, or the need to see or stroke the beloved, or telling and re-telling the story of first meeting. “like the beat, beat, beat of the tom tom when the jungle shadows fall like the tick, tick, tock of the stately clock as it stands against the wall like the drip, drip drip of the rain drops when the summer shower’s through a voice within me keeps repeating you, you, you… only you...” (Cole Porter, Night and Day) My desire to immerse myself in my newly-met adult daughter as a reality is as obsessive as any new parent. The primary means of contact is video cam, which has become a kind of surveillance for me. I stare at her mouth as it moves, her ear as she moves her head, her smile, her grimaces, her high cheekbones, her eyes that are like mine, the shape of her head, her teeth that are like her father’s… hundreds of candid pictures screen shot over a year and a half were the source of the video images.

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The novel manuscript Fragrance of Night is a crime novel set in Indonesia. Raymond Chan, struggling to deal with the death of his Australian wife, returns to his country of birth, Indonesia. Ostensibly he returns to attend his cousin Lee’s wedding but he is also in search of some meaning in his life. He is drawn into a local murder mystery, and with the help of a young, Javanese policeman, he is soon investigating suspects and motives. Raymond finds himself becoming increasingly enamoured with the main suspect, Lani, but ultimately, once the murder mystery is solved, Raymond loses her. The exegesis examines crime fiction as a genre, in particular Indonesian crime fiction and notions of postcolonialism and hybridisation. Within this broader context, it analyses works by Indonesian crime fiction writer S Mara Gd, postcolonial crime fiction and novels written in English but set in ‘exotic’ locale. The formulation of my novel Fragrance of Night was informed by the examination of the machinations of hybridised crime fiction and the more general rules of the crime fiction genre.

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Population size is crucial when estimating population-normalized drug consumption (PNDC) from wastewater-based drug epidemiology (WBDE). Three conceptually different population estimates can be used: de jure (common census, residence), de facto (all persons within a sewer catchment), and chemical loads (contributors to the sampled wastewater). De facto and chemical loads will be the same where all households contribute to a central sewer system without wastewater loss. This study explored the feasibility of determining a de facto population and its effect on estimating PNDC in an urban community over an extended period. Drugs and other chemicals were analyzed in 311 daily composite wastewater samples. The daily estimated de facto population (using chemical loads) was on average 32% higher than the de jure population. Consequently, using the latter would systemically overestimate PNDC by 22%. However, the relative day-to-day pattern of drug consumption was similar regardless of the type of normalization as daily illicit drug loads appeared to vary substantially more than the population. Using chemical loads population, we objectively quantified the total methodological uncertainty of PNDC and reduced it by a factor of 2. Our study illustrated the potential benefits of using chemical loads population for obtaining more robust PNDC data in WBDE.

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Rockfishes (Sebastes spp.) are an important component of North Pacific marine ecosystems and commercial fisheries. Because the rocky, high-relief substrate that rockfishes often inhabit is inaccessible to standard survey trawls, population abundance assessments for many rockfish species are difficult. As part of a large study to classify substrate and compare complementary sampling tools, we investigated the feasibility of using an acoustic survey in conjunction with a lowered stereo-video camera, a remotely operated vehicle, and a modified bottom trawl to estimate rockfish biomass in untrawlable habitat. The Snakehead Bank south of Kodiak Island, Alaska, was surveyed repeatedly over 4 days and nights. Dusky rockfish (S. variabilis), northern rockfish (S. polyspinis), and harlequin rockfish (S. variegatus) were the most abundant species observed on the bank. Backscatter attributed to rockfish were collected primarily near the seafloor at a mean height off the bottom of 1.5 m. Total rockfish backscatter and the height of backscatter off the bottom did not differ among survey passes or between night and day. Biomass estimates for the 41 square nautical-mile area surveyed on this small, predominantly untrawlable bank were 2350 metric tons (t) of dusky rockfish, 331 t of northern rockfish, and 137 t of harlequin rockfish. These biomass estimates are 5–60 times the density estimated for these rockfish species by a regularly conducted bottom trawl survey covering the bank and the surrounding shelf. This finding shows that bottom trawl surveys can underestimate the abundance of rockfishes in untrawlable areas and, therefore, may underestimate overall population abundance for these species.

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© 2015. American Geophysical Union. All Rights Reserved.The role of surface and advective heat fluxes on buoyancy-driven circulation was examined within a tropical coral reef system. Measurements of local meteorological conditions as well as water temperature and velocity were made at six lagoon locations for 2 months during the austral summer. We found that temperature rather than salinity dominated buoyancy in this system. The data were used to calculate diurnally phase-averaged thermal balances. A one-dimensional momentum balance developed for a portion of the lagoon indicates that the diurnal heating pattern and consistent spatial gradients in surface heat fluxes create a baroclinic pressure gradient that is dynamically important in driving the observed circulation. The baroclinic and barotropic pressure gradients make up 90% of the momentum budget in part of the system; thus, when the baroclinic pressure gradient decreases 20% during the day due to changes in temperature gradient, this substantially changes the circulation, with different flow patterns occurring during night and day. Thermal balances computed across the entire lagoon show that the spatial heating patterns and resulting buoyancy-driven circulation are important in maintaining a persistent advective export of heat from the lagoon and for enhancing ocean-lagoon exchange.