2,742 research outputs found
Improved underwater image enhancement algorithms based on partial differential equations (PDEs)
The experimental results of improved underwater image enhancement algorithms
based on partial differential equations (PDEs) are presented in this report.
This second work extends the study of previous work and incorporating several
improvements into the revised algorithm. Experiments show the evidence of the
improvements when compared to previously proposed approaches and other
conventional algorithms found in the literature.Comment: 22 pages, 6 figure
An Overview of the Northern Gulf of Mexico Ecosystem
The Gulf of Mexico is a large marine ecosystem (LME) bordered by the southern United States, Mexico, and Cuba. This general overview of its northern portion covers physiography, significant oceanographic features, the influence of major rivers and freshwater, biological productivity, and food web characteristics. It then describes the pelagic and benthic components of the major habitats: oceanic (continental slope and abyssal plain), continental shelf and bays, estuaries, and marshes, with descriptions of prominent processes and some dominant organisms. For each habitat several species from a variety of trophic levels are introduced and their general role in the ecosystem discussed. In 2010 the northern portion of the Gulf was the site of the largest U.S. marine oil spill in history and is now the focus of an unprecedented restoration effort. Successful restoration of the northern Gulf will depend on an integrated view of this LME and the forces that maintain and change it. This introduction to the northern Gulf marine ecosystem should be useful for policy makers, informing decisions on proposed restoration actions
The analysis of spectra of novae taken near maximum
A project to analyze ultraviolet spectra of novae obtained at or near maximum optical light is presented. These spectra are characterized by a relatively cool continuum with superimposed permitted emission lines from ions such as Fe II, Mg II, and Si II. Spectra obtained late in the outburst show only emission lines from highly ionized species and in many cases these are forbidden lines. The ultraviolet data will be used with calculations of spherical, expanding, stellar atmospheres for novae to determine elemental abundances by spectral line synthesis. This method is extremely sensitive to the abundances and completely independent of the nebular analyses usually used to obtain novae abundances
The responsiveness of the uterine fibroid symptom and health-related quality of life questionnaire (UFS-QOL)
Abstract Background A number of noninvasive alternatives to hysterectomy have become available as treatments for uterine fibroids. These alternative therapies, however, may not relieve all symptoms. Consequently, the need for patient-reported outcomes to assess symptom reduction of uterine fibroids has become increasingly important to evaluate the clinical success of patients who choose these alternative therapies. The purpose of the study was to examine the responsiveness of the Uterine Fibroid Symptom and Health-Related Quality of Life Questionnaire (UFS-QOL) with treatment of uterine fibroids. Methods The responsiveness of the UFS-QOL was assessed as a post-hoc analysis of patients treated with MRI-guided focused ultrasound thermal ablation (MRgFUS) for uterine fibroids. The UFS-QOL and SF-36 were completed at baseline and months 1, 3, and 6. Patient perceived overall treatment effect (OTE) was assessed at month 3, while satisfaction with treatment was collected at month 6. The responsiveness of the UFS-QOL was examined using effect sizes and change scores by patient-reported overall treatment effect and satisfaction. Results A total of 102 women with complete UFS-QOL data were included in the analysis; the mean age was 45 years and 79% were Caucasian. From baseline to 6 months, significant improvements were observed in UFS-QOL Symptom Severity and all Health-Related Quality of Life (HRQL) subscale scores (p Conclusion The UFS-QOL is responsive to treatment for uterine fibroids and is a useful outcome measure for uterine-sparing uterine fibroid treatments.</p
Experimental Evaluation of Ultrasonic Simulation Techniques in Anisotropic Material
The high performance of the available computer technology provides the possibility to simulate the real life for ultrasonic inspections in terms of primary ultrasonic data like rf-time signals. For isotropic material codes like Generalized Point Source Synthesis (GPSS) or Elastodynamic Finite Integration Technique (EFIT) and the theoretical predictions correlate well with experimental results. Recently, the codes mentioned above have been extended to operate also in anisotropic material. In a first step the codes GPSS and EFIT have been expanded to work in materials of parallel oriented columnar grain structure with transversely isotropic symmetry. In order to verify these codes a set of experiments was carried out on weld metal pads and on welds of defined grain structure. Radiation, propagation, reflexion on boundaries and interaction of the sound field with defects for the modes “through transmission” and “pulse echo” were simulated and compared with the experiment
Efeito do espaçamento de plantio e do teor de água na massa específica aparente e massa de mil grãos dos grãos de soja.
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