Movie Images Research Articles

Large–Scale Dynamics of an Unconfined Precessing Jet Flame

Visual observations, high speed movie sequences and image processing techniques have been used to examine unconfined vertical lifted turbulent diffusion flames issuing from precessing jeta (PJ) nozzles. These techniques provide qualitative information about the dynamic motions in the flame and quantitative data on the size and number of flame structures, the celerity of those structures, flame dimensions, residence times and characteristic strain rates. The information is used to provide new insight into the flame stabilisation mechanism of, and combustion processes occurring in, a PJ flame and to enable a comparison with similar studies in free turbulent jet diffusion flames and pool fires. Large-scale structures are seen to form near to the base of the PJ flame and move downstream with a slow, nearly constant speed in a manner reminiscent of the puffing motions in a pool fire. The entrainment and mixing of these structures is such that the flame tip oscillates as the residual unburned mixture in each structure, becomes combustible and burns out rapidly as a single entity. It is proposed that the puffing motions in these unconfined flames are the result of a buoyant instability, which is analogous to that in a pool fire. However the buoyant puff structures are the result, not the cause, of the stabilisation process. The high stability of the PJ flame, previously reported, is deduced to be related to the rapid decay in jet velocity and to the increase in entrainment which occurs in and upstream from the stabilisation region. The frequency of puffing is found to be uncorrelatetagging.bd with the frequency of precession. Global residence times and characteristic rates of shear are also measured and found to be reduced relative to those in a simple jet flame. The implications of the reduced shear on models of NOx generation in jet flames is discussed.

Visual Perception and Motion Picture Spectatorship

Watching his parents' home video, I see Erik, who is capering happily at his second birthday party. Gazing at a Polaroid snapshot, I look at Julie, who looks ravishing in a royal blue dress. Screening the documentary Unzipped (Douglas Keeves, 1995), I see fashion designer Isaac Mizrahi, who is getting a haircut in his studio. While perfectly ordinary, these sentences seem to have the philosophically troubling implication that I, the viewer, am having the same sort of perceptual experience of the depicted objects as I would have if the objects themselves were right in front of me. Could it actually be that, for a time, I think or believe myself in the presence not of images but of that which is portrayed?' Or is there a sense in which I really am seeing, as if through a window, Erik, Julie, Mizrahi, their observable features, and their actions? Or are these ordinary linguistic expressions concerning relations to photographed items just conceptually inconvenient ways of communicating the fact that the speaker sees one and only one thing, namely, a picture of so and so? While one or two film scholars might have gone so far as to suggest that spectators are prone to an illusionistic mode of reception, others have tried to explain how viewing photographic images could be both like looking through a window and free of egregious perceptual errors. Kendall Walton, who does not think that people tend to forget that they're looking at movie images, argues that even when watching films about imaginary creatures like the Loch Ness Monster, viewers really do see something, like a large wooden model, through the moving picture.2 Against their putative transparency, Gregory Currie takes the more austere position-I shall call it a representation thesis-that when we look at photographic and cinematographic images, we see representations but not the things represented, our perceptual access being to the image and not to the referent.: In this paper, I propose a perspective designed to avoid some of the weaknesses of transparency, representation, and, of course, illusion theses. I do not use the term realist in connection with a program of descriptive or normative claims about film style or the cinema's aesthetic telos. Rather, I associate it with

“It Belongs in a Museum”: The Image of Museums in American Film, 1985–1995

Introduction My image of museums before working for them was based on a movie picture. I imagined hidden treasures in dust-covered crates, nerdy scientists working on obscure and dangerous serums, dashing curators wining and dining wealthy donors and visitors enamored with objects taking them back hundreds of thousands of years. It was a very romantic image, one which I still have. But these images of museums are not just quaint pictures. Several visitor study surveys say that many people have an image of museums that have been constructed by movies that they have seen (Ernst & Young 21; N.L. Hushion and Associates, Health Consultants and Angus Reid Group 18). The study of such images, then, is an opportunity to see what type of museum stereotypes the public is exposed to and, more importantly, provides an opportunity to examine what museums can learn from movies. The study which follows focuses on the perception of museums in popular American film over the last decade. The resulting analysis is designed to provide more than a comparison between the image held of museums by Hollywood and the image held of museums by museum professionals. The act of verifying or contradicting the results of visitors' surveys or of taking a side in the debate between old and new museology is not the point of this paper. I am more interested in exploring the historically based, cultural stereotypes which are evident in the movie images themselves. In doing so, I hope to find out what role Hollywood has assigned museums to play in society and how museums can learn from these portrayals. The museum as a place of exclusivity is by far the most popular movie stereotype. Museum buildings are castle-like structures with long staircases, rows of columns, palatial gallery spaces and marble floors. Its objects are famous works of art or objects of mythical ancestry displayed in darkened galleries protected by elaborate security systems. Its receptions are glamorous affairs with guests dressed in black tie and sequin gowns. And its visitors are young, white, well-educated professionals. This image of the museum, however, is not a desirable one according to museum professionals (and some movie characters). It flies in the face of what many museologists have been trying to do for the last twenty years-make the museum a more comfortable place for all members of society. However, one could also argue that such images of exclusivity appeal to the movie audience's need to fantasize. Methods How did I analyze these films? I broke them down into their component parts. Lighting, background sound and music, dialogue, editing and the physical appearance of the museum were each analyzed separately (Monaco 132). After watching each movie as a whole, taking notes on the plot and subplots of each, I went back to only those segments of the film which were set in a museum. I then viewed these segments five more times looking at the component parts listed above. The use of dialogue in the movie, as one example of the use of film elements, was particularly pertinent to the portrayal of museums. Mixed with tone of voice and body language, dialogue tells us exactly what the characters think and feel. Vini's whiny rejection of Angie's (Geena Davis') invitation to go to an art gallery, in the movie Angie (1994), indicates his belief that the museum is boring and the Joker's (Jack Nicholson's) sarcastic remark about broadening one's mind at the Flugelheim Museum, in Batman (1989), suggests that he hates art and the civilization which it represents. What follows then is a discussion of how all these elements combine to portray the exclusive museum. Results and Discussion The Museum as Architecture It's a beautiful building. Somewhere, Frank Lloyd Wright is eating his heart out. Neal (Martin Landau) says this to Vincent (Richard Gere) in order to reassure him that the architectural plans for the new museum of anthropology are world class. …

Echo-Planar Imaging: Magnetic Resonance Imaging in a Fraction of a Second

Progress has recently been made in implementing magnetic resonance imaging (MRI) techniques that can be used to obtain images in a fraction of a second rather than in minutes. Echo-planar imaging (EPI) uses only one nuclear spin excitation per image and lends itself to a variety of critical medical and scientific applications. Among these are evaluation of cardiac function in real time, mapping of water diffusion and temperature in tissue, mapping of organ blood pool and perfusion, functional imaging of the central nervous system, depiction of blood and cerebrospinal fluid flow dynamics, and movie imaging of the mobile fetus in utero. Through shortened patient examination times, higher patient throughput, and lower cost per MRI examination, EPI may become a powerful tool for early diagnosis of some common and potentially treatable diseases such as ischemic heart disease, stroke, and cancer.

Real-time movie imaging from a single cardiac cycle by NMR.

Using a 1-m-bore superconductive magnet at 0.1 T, whole-body transverse images through adult humans have been obtained at repetition times of 57 ms. The techniques used were minor variations of echo-planar imaging (EPI) employing large pulsed gradients to provide complete coverage of the plane in phase space, and low-angle RF excitation sequences allowing rapid repetition of the experiment. In addition active magnetic screening of the gradient coils was implemented to protect the surrounding magnet from the eddy currents induced by the necessarily fast switching of the large gradient fields.

Real-time image enhancement in NMR

Clinical NMR motion picture (movie) images can be produced routinely in real-time by ultra-high-speed echo-planar imaging (EPI). The single-short image quality depends on both pixel resolution and signal-to-noise ratio (S/N), both factors being intertradeable. If image S/N is sacrificed rather than resolution, it is shown that S/N may be greatly enhanced subsequently without vitiating spatial resolution or foregoing real motional effects when the object motion is periodic. This is achieved by a Fourier filtering process. Experimental results are presented which demonstrate the technique for a normal functioning heart.

Real-time movie images by nuclear magnetic resonance

Real-time movie images by nuclear magnetic resonance

Real time movie images by NMR.

We report the first real time NMR movie images obtained by studying cardiac motion in a rabbit. The images are produced using the high speed echo-planar method. Six frames from the movie loop are presented in this paper and demonstrate the snapshot ability of echo-planar imaging to freeze the heart motion in arbitrary phases in the cardiac cycle.

Real time movie images by NMR

Abstract We report the first real time NMR movie images obtained by studying cardiac motion in a rabbit. The images are produced using the high speed echo-planar method. Six frames from the movie loop are presented in this paper and demonstrate the snapshot ability of echo-planar imaging to freeze the heart motion in arbitrary phases in the cardiac cycle.

From "Sambo" to "Superspade":

FROM "SAMBO" TO "SUPERSPADE": By Daniel J. Leab Daniel J. Leab ofthe History Department ofColumbia University is the author ofa book on the early years Newspaper Guild. He has written articles and reviews in the Labor History, Journalism Quarterly, The Monthly Labor Review and otherjournals. This article is a condensation ofthe introduction to Professor Leab'sforthcoming book From "Sambo " to "Superspade: "The Black in Film, to bepublished by Simon & Shuster in 191 S. Until recently the movie image ofthe black has been a "Sambo" image. Beginning in the 1 890's when the first motion pictures were produced for exhibition in penny arcade peepshows and for decades thereafter, movie makers either ignored Negroes or with rare exceptions presented them as stereotyped characters who were objects ofridicule and condescension. And this stereotyping applied to men and women, adults and children. Sambo "was docile but irresponsible, loyal but lazy, humble but chronically given to lying and stealing" (to use the delineation ofthe image rendered by historian Stanley Elkins in a somewhat different context). Just about everything traditionally held to be of some value in the United States was absent from this movie stereotype of the Negro. Invariably, blacks were presented as subhuman, simpleminded, superstitious, and submissive. As portrayed in screen they exhibited qualities offoolish exaggeration and an apparently hereditary clumsiness and ignorance as well as an addictive craving for fried chicken and watermelon. The blacks' relationship with whites was on the whole depicted as one ofcomplete dependence, often with a kind ofchildlike attachment on the part of the Negro (1). The central character in the 1910 Lubin comedy Rastus in Zululand symbolizes the American film industry's treatment ofthe black as a Sambo figure. Rastus was described as "an odd-jobs man, that is he did oddjobs when he has to, but when there are a few small coins in his pocket he prefers to sleep." The film begins with Rastus searching for a place to sleep. He finds one in the sunlight. This rather offchoice ofa sleeping place is explained in bigoted fashion by the Lubin company's plot synopsis ofthe film: "a darky needs warmth." The sleeping Rastus dreams that he has gone to sea and has been shipwrecked in Zululand. Captured by savage cannibals, he has been placed in the community cooking pot. The entreaties ofthe chiefs daughter save Rastus from being part ofthe stew, but she is so obese and ugly that he chooses to return to the pot. He awakens just as the water has begun to boil and "is much relieved to find himselfwithin walking distance of a place where nerve tonic is sold." (2) Rastus in Zululand accurately reflects the racial prejudices and beliefs ofpre-World War I America, although in ascribing a certain joi de vivre to Rastus the film treated the black less viciously than some movies did other ethnic groups. The movie industry's changing treatment ofthese groups over the years reflected these groups' gradual assimilation by American society. But the black remained an outsider to that society. For decades, except for a few notable instances, the industry either ignored the Negro or utilized the Sambo image. So ingrained did this stereotype become that in 1935 an all-Negro film made for black audiences contained a scene, ostensibly humorous, in which an employer dictating a want ad uses the word "Negro" and each time his assistant (played broadly for laughs) writes "nigger." (3) The British filmmaker and movie critic Lindsay Anderson has said that "everyone who has seen more than halfa dozen films with his eyes open knows that ifthe cinema does not create the significant social movements ofour time, it intimately reflects them." Among social scientists and others concerned with the impact ofmovies on society there have been strong divisions ofopinion about whether movies influence an audience or whether they mirror its ideas, but there is in the American Dream. Almost from the American film industry's beginnings, the black on screen was left out ofthat dream, either by being ignored or by being presented as an object incapable ofpartaking by reason of a not quite human nature. (4) This treatment ofthe Negro had caused the respected blackjournalist Lester Walton to...