RESUMEN
Multirotor Unmanned Air Systems (UAS) represent a significant improvement in capability for Synthetic Aperture Radar (SAR) imaging when compared to traditional, fixed-wing, platforms. In particular, a swarm of UAS can generate significant measurement diversity through variation of spatial and frequency collections across an array of sensors. In such imaging schemes, the image formation step is challenging due to strong extended sidelobe; however, were this to be effectively managed, a dramatic increase in image quality is theoretically possible. Since 2015, QinetiQ have developed the RIBI system, which uses multiple UAS to perform short-range multistatic collections, and this requires novel near-field processing to mitigate the high sidelobes observed and form actionable imagery. This paper applies a number of algorithms to assess image reconstruction of simulated near-field multistatic SAR with an aim to suppress sidelobes observed in the RIBI system, investigating techniques including traditional SAR processing, regularised linear regression, compressive sensing. In these simulations presented, Elastic net, Orthogonal Matched Pursuit, and Iterative Hard Thresholding all show the ability to suppress sidelobes while preserving accuracy of scatterer RCS. This has also lead to a novel processing approach for reconstructing SAR images based on the observed Elastic net and Iterative Hard Thresholding performance, mitigating weaknesses to generate an improved combined approach. The relative strengths and weaknesses of the algorithms are discussed, as well as their application to more complex real-world imagery.
Asunto(s)
Compresión de Datos , Radar , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Diagnóstico por ImagenRESUMEN
STATEMENT OF PROBLEM: When making complete dentures, clinicians may have difficulty with selection of properly sized denture teeth. PURPOSE: The purpose of this study was to determine if there are specific measurements made on an edentulous cast that could be useful to clinicians for selection of proper maxillary anterior denture tooth width. MATERIAL AND METHODS: Following Institutional Review Board approval, measurements were made on 50 maxillary and mandibular sets of complete denture casts and their marked and contoured occlusion rims and record bases consecutively submitted to a dental laboratory. The following 6 measurements were recorded for each set of casts: left mid-maxillary to right mid-maxillary, representing the distance between the respective residual ridge crest points adjacent to each canine eminence; left retromolar pad to right retromolar pad; incisive papilla to left hamular notch; incisive papilla to right hamular notch; left hamular notch to right hamular notch; and incisive papilla to vibrating line. These measurements were statistically compared with the control, the canine-to-canine distance as marked on the contoured maxillary occlusion rim to indicate the relaxed commissures. The casts were also classified as small, medium or large based upon the tooth width specified by the commercial mold guide for their respective canine-to-canine control measurement. The estimation bias was determined for each of the 6 measurements, and for those measurements for which the bias was significantly different from zero, a bias-correction was applied. St. Laurent's coefficient was used to describe the agreement between each (bias-corrected) measurement and the canine-to-canine control. A commercial guide was used to determine the accuracy of each of the 6 bias-corrected measurements in classifying denture teeth width as small, medium or large as compared to the same classification using the canine-to-canine control. RESULTS: The bias-corrected measurement from the left hamular notch mark to the right hamular notch mark, obtained by adding 10 mm, exhibited the greatest degree of agreement with the control. This measurement was also the only one of the 6 that correctly classified more than 50% of both the medium and large casts. None of the 6 measurements classified more than 30% of the small casts correctly. CONCLUSIONS: Of the 6 measurements considered here, the bias-corrected measurement from left hamular notch mark to right hamular notch mark was preferred for selecting denture teeth width.
Asunto(s)
Diente Canino , Diseño de Dentadura , Incisivo/anatomía & histología , Arcada Edéntula/patología , Maxilar/patología , Modelos Dentales , Odontometría/métodos , Diente Artificial , Cefalometría/métodos , Diente Canino/anatomía & histología , Arco Dental/patología , Bases para Dentadura , Encía/anatomía & histología , Humanos , Diente Molar/anatomía & histología , Hueso Paladar/patología , Hueso Esfenoides/patología , Propiedades de SuperficieRESUMEN
OBJECTIVE: To determine correlates of human papillomavirus (HPV) vaccine acceptance for men. METHODS: A convenience sample of men aged 18 to 45 years read a one-page information sheet about HPV and the HPV vaccine, then completed a 29-item questionnaire. chi(2) tests were used to determine whether differences in demographic, sexual, and vaccine-related variables existed between levels of wanting the HPV vaccine. RESULTS: Positive correlates of HPV vaccine acceptance included higher education (P < .0001); hispanic ethnicity (P = .0003); wearing a seat belt most of the time (P = .02); regular tobacco use (P = <.001); not being sexually active (P = .0008); history of more than 10 female sexual partners (P = .0004); not having oral sex (P = .045); extreme worry about vaccine side effects (P < .0001); extreme concern about vaccine safety (P < .0001); the importance of getting vaccines (P < .0001); familiarity with HPV (P < .0001); and extreme importance of receiving the HPV vaccine (P < .0001). CONCLUSIONS: Men with greater general education, high-risk behaviors, and knowledge about HPV are more likely to want the HPV vaccine. Focused educational efforts should facilitate even wider acceptance of the HPV vaccine by men.
Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus , Aceptación de la Atención de Salud/estadística & datos numéricos , Vacunación/estadística & datos numéricos , Adolescente , Adulto , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales , Estadística como Asunto , Adulto JovenRESUMEN
OBJECTIVES: To determine men's attitudes toward receiving the human papillomavirus (HPV) vaccine. MATERIALS AND METHODS: Five hundred seventy-one men read a 1-page informational sheet about HPV and the HPV vaccine before completing a 29-item questionnaire. Descriptive statistics were calculated on all variables. RESULTS: Of these men, 33% wanted to receive the HPV vaccine, 27% did not, and 40% were undecided. The main reasons for wanting the vaccine included a desire to stay healthy (67.4%); prevention of cancer in my sexual partner(s) (52.9%); prevention of anal, penile, and head and neck cancer (41.0%); fear of cancer (33.4%); and prevention of genital warts (32.8%). Being in a monogamous relationship and not at risk (18.9%), not interested (13.8%), and not enough evidence yet to prove that it will help men (8.2%) were the main reasons for not wanting to be vaccinated. CONCLUSIONS: Although many men want to receive the HPV vaccine, more remain undecided. Pending favorable safety and efficacy results from a clinical trial for men, substantial factual education will likely convince many ambivalent men to receive the HPV vaccine.