864 resultados para camera shake


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Macroscopic features such as volume, surface estimate, thickness and caudorostral length of the human primary visual cortex (Brodman's area 17) of 46 human brains between midgestation and 93 years were studied by means of camera lucida drawings from serial frontal sections. Individual values were best fitted by a logistic function from midgestation to adulthood and by a regression line between adulthood and old age. Allometric functions were calculated to study developmental relationships between all the features. The three-dimensional shape of area 17 was also reconstructed from the serial sections in 15 cases and correlated with the sequence of morphological events. The sulcal pattern of area 17 begins to develop around 21 weeks of gestation but remains rather simple until birth, while it becomes more convoluted, particularly in the caudal part, during the postnatal period. Until birth, a large increase in cortical thickness (about 83% of its mean adult value) and caudorostral length (69%) produces a moderate increase in cortical volume (31%) and surface estimate (40%) of area 17. After birth, the cortical volume and surface undergo their maximum growth rate, in spite of a rather small increase in cortical thickness and caudorostral length. This is due to the development of the pattern of gyrification within and around the calcarine fissure. All macroscopic features have reached the mean adult value by the end of the first postnatal year. With aging, the only features to undergo significant regression are the cortical surface estimate and the caudorostral length. The total number of neurons in area 17 shows great interindividual variability at all ages. No decrease in the postnatal period or in aging could be demonstrated.

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The goal of this work is to develop a method to objectively compare the performance of a digital and a screen-film mammography system in terms of image quality. The method takes into account the dynamic range of the image detector, the detection of high and low contrast structures, the visualisation of the images and the observer response. A test object, designed to represent a compressed breast, was constructed from various tissue equivalent materials ranging from purely adipose to purely glandular composition. Different areas within the test object permitted the evaluation of low and high contrast detection, spatial resolution and image noise. All the images (digital and conventional) were captured using a CCD camera to include the visualisation process in the image quality assessment. A mathematical model observer (non-prewhitening matched filter), that calculates the detectability of high and low contrast structures using spatial resolution, noise and contrast, was used to compare the two technologies. Our results show that for a given patient dose, the detection of high and low contrast structures is significantly better for the digital system than for the conventional screen-film system studied. The method of using a test object with a large tissue composition range combined with a camera to compare conventional and digital imaging modalities can be applied to other radiological imaging techniques. In particular it could be used to optimise the process of radiographic reading of soft copy images.

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Usually the measurement of multi-segment foot and ankle complex kinematics is done with stationary motion capture devices which are limited to use in a gait laboratory. This study aimed to propose and validate a wearable system to measure the foot and ankle complex joint angles during gait in daily conditions, and then to investigate its suitability for clinical evaluations. The foot and ankle complex consisted of four segments (shank, hindfoot, forefoot, and toes), with an inertial measurement unit (3D gyroscopes and 3D accelerometers) attached to each segment. The angles between the four segments were calculated in the sagittal, coronal, and transverse planes using a new algorithm combining strap-down integration and detection of low-acceleration instants. To validate the joint angles measured by the wearable system, three subjects walked on a treadmill for five minutes at three different speeds. A camera-based stationary system that used a cluster of markers on each segment was used as a reference. To test the suitability of the system for clinical evaluation, the joint angle ranges were compared between a group of 10 healthy subjects and a group of 12 patients with ankle osteoarthritis, during two 50-m walking trials where the wearable system was attached to each subject. On average, over all joints and walking speeds, the RMS differences and correlation coefficients between the angular curves obtained using the wearable system and the stationary system were 1 deg and 0.93, respectively. Moreover, this system was able to detect significant alteration of foot and ankle function between the group of patients with ankle osteoarthritis and the group of healthy subjects. In conclusion, this wearable system was accurate and suitable for clinical evaluation when used to measure the multi-segment foot and ankle complex kinematics during long-distance walks in daily life conditions.

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This report presents the results of surveys to determine studded tire usage in Iowa. Also reported are the results of measurements of transverse pavement profiles at selected locations where the pavement is subjected to a high volume of traffic. The surveys were made in January of each of the years 1969 through 1978 and in each of 27 areas into which the state was divided. Estimates of studded tire usage were also made at various locations on Interstate highways in Iowa. The lowest percentage of studded tires was observed in the initial count during the winter of 1968-69. Two years later the percentage had increased to the maximum (22.6%) and then began a gradual decline. The latest count in January of 1978 indicated 8.5% of the cars had studded tires. The decline in the use of studded tires is attributed to the efforts of the Iowa DOT and others to obtain a ban on studded tires and a continual increase in the use of radial tires with claims of improved traction. The wear measurements were recorded by camera. It was found that studded tires have worn ruts in Iowa pavements as deep as 5/16 inch. The ruts lead to water on the pavement and this causes hydroplaning, as well as splash and spray. The conclusion of the study was that studded tires should be banned in Iowa.

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Five test flights were conducted to study the use of Global Positioning System (GPS) in Photogrammetry, three in Iowa, one each in California and Texas. These tests show that GPS can be used to establish ground control by the static method and to determine camera location by the kinematic method. In block triangulation, six GPS controls are required and additional elevation control along the centerline is also required in strip triangulation. The camera location determined by aerial triangulation depends on the scale of the photography. The 1:3000 scale photography showed that the absolute accuracy of the camera location by GPS is better than five centimeters. The 1:40000 scale photography showed that the relative accuracy of the camera location by GPS is about one millimeter. In a strip triangulation elevation control is required in addition to the camera location by GPS. However, for block triangulation camera location by GPS is sufficient. Pre-targeting of pass and tie points gives the best results in both block and strip triangulation. In normal mapping for earth work computations the use of 1:6000 scale photography with GPS control instead of 1:3000 scale is recommended. It is recommended that research be done in the use of GPS for navigation in aerial photographic missions. It is highly recommended that research be done in the use of GPS to determine tip and tilt of the aerial camera, that is required in stereoplotting.

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The objective of this project was to use a Global Positioning System (GPS) to determine the aerial camera location and orientation that best facilitated mapping done from aerial photographs without any ground control. Four test flights were conducted. The first test flight was performed in June 1993 at St. Louis, with the objective of testing the multiantenna concept using two antenna on the aircraft. The second test in August 1993 was conducted over the Iowa State University (ISU) campus at Ames. This flight evaluated the use of GPS for pinpoint navigation. The third test flight over St. Louis was flown in October 1993, with four antenna on aircraft; its objective was to evaluate the 3DF GPS receiver and the antenna locations. On the basis of the results of these three tests, a final test flight over the Mustang Project area in Ames and the ISU campus was conducted in June 1994. Analysis of these data showed that airborne GPS can be used (1) in pinpoint navigation with an accuracy of 25 m or better, (2) to determine the location of the camera nodal point with an accuracy of 10 cm or better, and (3) to determine the orientation angles of the camera with an accuracy of 0.0001 radians or better. In addition, the exterior orientation elements determined by airborne GPS can be used to rectify aerial photos, to produce orthophotos, and in direct stereo plotting. Further research is recommended in these areas to maximize the use of airborne GPS. The report is organized in the following chapters: (1) Introduction; (2) Photogrammetry and Kinematic GPS; (3) Analysis of First Test; (4) Analysis of Second Test; (5) Analysis of Third Test; (6) Analysis of Final Test; (7) Applications of Airborne GPS; and (8) Conclusion and Recommendation.

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This work proposes a parallel architecture for a motion estimation algorithm. It is well known that image processing requires a huge amount of computation, mainly at low level processing where the algorithms are dealing with a great numbers of data-pixel. One of the solutions to estimate motions involves detection of the correspondences between two images. Due to its regular processing scheme, parallel implementation of correspondence problem can be an adequate approach to reduce the computation time. This work introduces parallel and real-time implementation of such low-level tasks to be carried out from the moment that the current image is acquired by the camera until the pairs of point-matchings are detected

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Experience Iowa’s natural beauty and all the fun our state parks off er as you make memories with family and friends. With an array of activities for outdoor enthusiasts of all ages, there’s something for everyone whether you’re visiting for an afternoon or a week. Grab a camera, a loved one or two, a sense of adventure and come explore. Hike to a breathtaking overlook, canoe along a peaceful river, fish for trout, learn about native species, roast marshmallows over the campfire and more at one of Iowa’s 72 state parks.

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Aquest treball consta d’una investigació amb una pràctica d’activitats basades en el moviment corporal amb un infant diagnosticat amb Trastorn de Dèficit D’Atenció (TDA), amb la intenció de tractar i treballar els problemes que pateix de concentració i atenció. Aquesta pràctica va tenir lloc a l’Escola Sant Jordi de Navàs. Es va analitzar a l’alumne/a en concret, però es van treballar totes les activitats amb tot el grup classe. Les activitats van ser dissenyades a partir dels aprenentatges a la universitat durant la carrera i també de diferents autors citats al marc teòric. Els instruments de recollida de dades que es van utilitzar són les tècniques d’observació i el diari de camp i la càmera de fotos i de vídeo per enregistrar moments en concret. Aquests instruments van donar lloc a l’anàlisi i a la valoració final de les sessions de la pràctica realitzada, en la que es va poder observar una millora en l’atenció, la concentració, l’ interès, la relació amb els companys, etc, aconseguint els objectius proposats al principi. Si el moviment corporal ajuda a millorar als infants que pateixen aquest trastorn i a tots els altres és aconsellable que a l’escola es busquin estratègies i formes de treballar-ho, en qualsevol àrea, per a motivar i fer créixer els aprenentatges de tots els alumnes.

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Aquesta petita investigació es divideix en dues parts. La primera, basada en els estudis teòrics, ofereix una visió de la importància de la creativitat dins i fora l’escola i de la didàctica d’aquesta a través de l’experiència de fer cinema. Fer d’actor, guionista, càmera, maquillador, escenògraf, entre d’altres, és una eina metodològica que potencia la creativitat dels alumnes? Ho investiguem a la segona part d’aquest document mitjançant estratègies d’avaluació de la creativitat. I els resultats indiquen que els infants que han realitzar el projecte de fer cinema tenen més bona qualificació en tots els aspectes avaluats.

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Addresses the problem of estimating the motion of an autonomous underwater vehicle (AUV), while it constructs a visual map ("mosaic" image) of the ocean floor. The vehicle is equipped with a down-looking camera which is used to compute its motion with respect to the seafloor. As the mosaic increases in size, a systematic bias is introduced in the alignment of the images which form the mosaic. Therefore, this accumulative error produces a drift in the estimation of the position of the vehicle. When the arbitrary trajectory of the AUV crosses over itself, it is possible to reduce this propagation of image alignment errors within the mosaic. A Kalman filter with augmented state is proposed to optimally estimate both the visual map and the vehicle position

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The Federal Highway Administration estimates that red light running causes more than 100,000 crashes and 1,000 fatalities annually and results in an estimated economic loss of over $14 billion per year in the United States. In Iowa alone, a statewide analysis of red light running crashes, using crash data from 2001 to 2006, indicates that an average of 1,682 red light running crashes occur at signalized intersections every year. As a result, red light running poses a significant safety issue for communities. Communities rarely have the resources to place additional law enforcement in the field to combat the problem and they are increasingly using automated red light running camera-enforcement systems at signalized intersections. In Iowa, three communities currently use camera enforcement since 2004. These communities include Davenport, Council Bluffs, and Clive. As communities across the United States attempt to address red light running, a number of communities have implemented red light running camera enforcement programs. This report examines the red light running programs in Iowa and summarizes results of analyses to evaluate the effectiveness of such cameras.

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Aim  Avoiding 'mini-laparotomy' to extract a colectomy specimen may decrease wound complications and further improve recovery after laparoscopic surgery. The aim of this study was to develop a new technique for transrectal specimen extraction (TRSE) and to compare it with conventional laparoscopy (CL) for left sided colectomy. Method  Eleven patients with benign disease requiring either sigmoid or left colon resection underwent TRSE. The unfired circular stapler was inserted transanally and used as a guide to suture-close the recto-sigmoid junction laparoscopically and as a handle to pull the sutured sigmoid through the opened rectum inside a laparoscopic camera bag. The anvil was inserted into the lumen of the intussuscepted sigmoid and pushed to the level of the anastomosis. The anastomosis was fashioned end-to-end in the first patients and side-to-end in the following patients to improve safety. Intra-operative and postoperative outcomes of patients undergoing TRSE were compared with those of a group of 20 patients undergoing CL, who were matched for type of resection, body mass index and age. Results  The procedure was successful in all but the first patient who was converted to conventional laparoscopic colectomy without any additional morbidity. Two patients in the end-to-end anastomosis group, but none in the side-to-end group, developed peri-anastomotic sepsis. Compared with CL, patients undergoing TRSE did not show any significant differences in operative time, recovery or morbidity. Conclusion  Transrectal specimen extraction after left colectomy using the circular stapler technique is feasible. A side-to-end anastomosis appears safer than an end-to-end anastomosis. Further studies are needed to explore the potential advantages of this procedure over CL.

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According to Ray Harryhausen, a special effects expert in the film industry, "Gustave Doré would have made a great director of photography . . . He saw things from the point of view of the camera." Doré's work has had a permanent impact on the imaginative realm of film since its very early days. In return, the silver screen has etched Doré into the 20th century imagination. Almost every film about the Bible since The Life and Passion of Jesus Christ produced by Pathé in 1902 refers to his illustrations, and every film adaptation of Dante or Don Quixote has used him as a model, from Georg Wilhelm Pabst and Orson Welles to Terry Gilliam. All films dealing with life in London in the Victorian era by directors ranging from David Lean, to Roman Polanski and Tim Burton draw on the visions in London: a pilgrimage for their sets. A large number of dream fantastical or phantasmagorical scenes take their inspiration from Doré's graphic world, beginning with Georges Méliès' A Trip to the Moon in 1902. In the realm of cartoons and animation, Walt Disney owes a huge debt to Doré. Doré primal forests, from Atala in particular, were also used in the various versions of King Kong from 1933 to the 2005 film by Peter Jackson, who had already drawn on Doré for The Lord of the Rings. Jean Cocteau was also indebted to the illustrations for Perrault's Fairy Tales for his Beauty and the Beast (1945), as was George Lucas for the character Chewbacca in Star Wars (1977) and even the Harry Potter film series. Through his influence on film history, Doré shaped the mass culture imagination.

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Purified, [131I]-labeled goat antibodies against carcinoembryonic antigen, which have been shown to localize in human carcinoma in nude mice, were injected into 27 patients with carcinoma. Patients were scanned with a scintillation camera at various intervals. In 11 patients, radioactivity was detectable in the tumor 48 hours after injection. Computerized subtraction of blood-pool radioactivity provided clearer pictures in positive cases, but in 16 patients the scans remained doubtful or negative. To study the specificity of [131I]-antibody localization, we gave some patients simultaneous injections of [125I]-labeled normal IgG. Both isotopes were measured by means of scintillation counting in tumors and normal tissues recovered after surgery. The results demonstrated that only the anti-CEA antibodies localized in tumors. However, the total antibody-derived radioactivity in the tumor was only about 0.001 of the injected dose. We conclude that, despite the present demonstration of specificity, this method of tumor detection is not yet clinically useful.