5,767 research outputs found
Does the scatterometer see wind speed or friction velocity?
Studies of radar backscatter from the sea surface are referred either to the wind speed, U, or friction velocity, u(sub *). Bragg scattering theory suggests that these variations in backscatter are directly related to the height of the capillary-gravity waves modulated by the larger waves in tilt and by straining of the short wave field. The question then arises as to what characteristic of the wind field is most probably correlated with the wave number spectrum of the capillary-gravity waves. The justification for selecting U as the appropriate meteorological parameter to be associated with backscatter from L-band to Ku-band are reviewed. Both theoretical reasons and experimental evidence are used to demonstrate that the dominant parameter is U/C(lambda) where U is the wind speed at a height of about lambda/2 for waves having a phase speed of C(lambda)
Growth of a mat-forming photograph in the presence of UV radiation
Knowledge of the survival and growth of microorganisms in the presence of ultraviolet radiation is important for understanding the potential for life to exist in environments exposed to high fluxes of UV radiation. The growth of a mat-forming phototrophic prokaryote, Chloroflexus aurantiacus, was examined in the presence of continuous high UV irradiation under otherwise optimal growth conditions. Evidence was sought for an intrinsic ability to grow in the presence of UV radiation in a carefully chosen organism known to be unusually resistant to UV radiation, of ancient lineage among the phototrophs, to resemble ancient microfossils from the Precambrian, and to be a mat-former. It was assumed that even a high intrinsic UV resistance would be inadequate for survival and growth in the presence of very high UV fluxes, and iron (Fe3+) was selected as a common, abundant UV-absorbing substance that might protest microorganisms growing in or under iron-bearing sediments. The effectiveness of Fe(3+) was tested as a UV protective agent at low concentrations in thin layers. It was concluded that intrinsic UV resistance in some organisms may account for growth, not just survival, of these organisms when exposed to high UV fluxes under otherwise optimal growth conditions in an anoxic environment. It was also concluded that Fe(3+) bearing sediments of 1 mm or less in thickness may provide an adequate shield against high UV fluxes permitting the growth of microorganisms just below their surface. As long as growth conditions were met, then the evolution and development of microorganisms would not be hampered by high UV fluxes impinging upon the surface of iron-bearing sediments
The elevation, slope, and curvature spectra of a wind roughened sea surface
The elevation, slope and curvature spectra are defined as a function of wave number and depend on the friction velocity. There are five wave number ranges of definition called the gravity wave-gravity equilibrium range, the isotropic turbulence range, the connecting range due to Leykin Rosenberg, the capillary range, and the viscous cutoff range. The higher wave number ranges are strongly wind speed dependent, and there is no equilibrium (or saturated) capillary range, at least for winds up to 30 meters/sec. Some properties of the angular variation of the spectra are also found. For high wave numbers, especially in the capillary range, the results are shown to be consistent with the Rayleigh-Rice backscattering theory (Bragg scattering), and certain properties of the angular variation are deduced from backscatter measurements
Renormalization Group Study of the Intrinsic Finite Size Effect in 2D Superconductors
Vortices in a thin-film superconductor interact logarithmically out to a
distance on the order of the two-dimensional (2D) magnetic penetration depth
, at which point the interaction approaches a constant. Thus,
because of the finite , the system exhibits what amounts to an
{\it intrinsic} finite size effect. It is not described by the 2D Coulomb gas
but rather by the 2D Yukawa gas (2DYG). To study the critical behavior of the
2DYG, we map the 2DYG to the massive sine-Gordon model and then perform a
renormalization group study to derive the recursion relations and to verify
that is a relevant parameter. We solve the recursion relations
to study important physical quantities for this system including the
renormalized stiffness constant and the correlation length. We also address the
effect of current on this system to explain why finite size effects are not
more prevalent in experiments given that the 2D magnetic penetration depth is a
relevant parameter.Comment: 8 pages inRevTex, 5 embedded EPS figure
Joint TEFL Training of Peace Corps Volunteers and Host Country Nationals in Tongo: An Experience and Recommendations
The author describes her experience as TEFL Coordinator for a Peace Corps training program for both Americans and Africans in Togo. The background of TEFL training in Togo is outlined. The organization of the training program is presented, along with problems encountered and recommendations for future training programs. The author also discusses the content of the training program in light of the rationale and goals of training, and shares some personal insights gained as a result of her expereince. Extensive appendices contain copies of the materials used during the training program
A Performance and Pedagogical Approach of Adagio from Mozart\u27s Clarinet Concerto, K.622
Wolfgang Amadeus Mozart (January 27, 1756 – December 5, 1791) composed his Clarinet Concerto, K.622 during his final years for his dear friend, Anton Stadler. Praised by many performers and scholars, the Clarinet Concerto, K.622 is recognized as one of the best of concertos from the Classical era. This thesis is divided into three sections. The first section covers the historical context of the concerto and its intended instrument, the basset clarinet. The second chapter examines sources, in the format of an annotated bibliography, to define aspects of a historically-informed performance from both a performance and pedagogical standpoint. The final chapter goes into depth about how to incorporate the information from the annotated bibliography and the historical context to perform or teach the second movement of the concerto (“Adagio”) with an authentic purpose
The Effects of Rape Myths and Expert Testimony on Juror Decision Making in a Sexual Assault Case
When a sexual assault case is tried in court there is often a lack of physical evidence, leading jurors to rely on the general information they know about a topic when determining a verdict. When jurors rely on their general knowledge, preexisting stereotypes and prejudice can influence their decision. One type of stereotype is rape myths- false beliefs about rape victims, the situation surrounding a rape, and rapists. One understudied rape myth is the myth that victims who report their rape immediately are more credible than those who wait to report. Rape myths can be used to shift blame away from a perpetrator and onto a victim and to justify the sexual victimization of women. Within the court system, expert testimony has been used to debunk preexisting beliefs about many topics, such as rape myths. The current study sought to analyze the effect of expert testimony on mock jurors’ levels of rape myth acceptance and victim blame. In this online study, participants read a sexual assault vignette in which the victim reported a rape to the police immediately or delayed by one week. Participants were also randomly assigned to receive an expert testimony or no expert testimony. Results indicated that the use of an expert testimony was effective in reducing belief in the myth that timing of report was related to victim credibility. Results also showed that men were significantly higher in levels of victim blame, belief in timing myth, and general levels of rape myth acceptance than women. Implications and limitations of findings are discussed
Spatial Assessment of Urban Growth in Cities of the Decapolis; and the implications for modern cities
The Levant’s Decapolis was a network of ten cities in Greco-Roman Israel, Jordan, and Syria that established a thriving economic community. The Decapolis was home to ancient and modern cities like Damascus (Dammásq) and Amman (Philadelphia). Despite the various origins of these cities, Roman administration and their city planners oversaw the implementation of idealized Roman city form throughout the region. Three Decapolis cities represent intriguing examples of the larger confederation. Philadelphia (Amman), Gerasa (Jerash), and Gadara (Umm Qais) represent cities of common original urban form which developed drastically diverse urban morphologies over time.
Spatial analyses of these cities required working from the modern urban plans to Roman- era morphologies. Project methodology involved the assessment of satellite and flyover imagery for both the modern city structure and the extant ancient city infrastructure and remains. Utilizing remote-sensing applications enabled in-depth analyses of land use and past urban structures. As the older city forms and infrastructure were identified, their reconstructions based on archaeological excavations and historical accounts were crucial. Preliminary results revealed important aspects about the urban form of each city over time. For example, Amman is now completely surrounded by its Roman ruins, radiating from the old Roman center into the large city today, little affected by topography. By the 20th century, Jerash had enlarged primarily to the east, however, more recently into a distinctive radial pattern. Umm Qais, however, has expanded eastward of its old center in an organic morphology following topography and watercourses. Urban morphometric analysis is vital for explaining and visualizing how Decapolis cities had developed and created powerful links, intertrade routes, and economies – the thrust of this study
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