Imaging System

Top PDF Imaging System:

ANALYSIS OF VOCAL FOLD VIBRATION DURING REGISTER CHANGE BY HIGH SPEED DIGITAL IMAGING SYSTEM

ANALYSIS OF VOCAL FOLD VIBRATION DURING REGISTER CHANGE BY HIGH SPEED DIGITAL IMAGING SYSTEM

Physiological study of prosody is indispensable in terms not only of the physiological interest but also of the evaluation and treatment for pathological cases of prosody. In free talk, the changes of vocal fold vibration are found frequently and these phenomena are very important prosodic events. Purpose and Method: To analyze the vocal fold vibration at the register change as the model of prosodic event, using our high speed digital imaging system at a rate of 4,500 images of 256 256 pixels per second. Tasks: Sustained phonations containing register changes. Results: Two major categories were found in the ways of vocal fold vibrations at the register change. In one category, changes were very smooth. In another, changes were not so smooth with some additional events, such as the anterior-posterior phase difference of the vibration, the abduction of the vocal folds, or the interruption of the phonation. Discussion: For the study of prosody, our high speed digital imaging system is a very powerful tool by which physiological information can be obtained.
Mostrar más

5 Lee mas

Osiris— The optical, spectroscopic and infrared remote imaging system for the Rosetta orbiter

Osiris— The optical, spectroscopic and infrared remote imaging system for the Rosetta orbiter

In response to the Announcement of Opportunity (AO) (ESA document, 1996), the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) was the only experiment proposed to ESA as the main imaging system on the Rosetta spacecraft. The "Red Report" (ESA document, 1993), which outlined the goals and implementation of the Rosetta mission, included a dedicated scientific imaging system as part of the strawman payload. However, funding problems have led to considerable uncertainty as to whether the ESA Member States can fund such a system completely. These problems have not, at time of writing (July 1996) been resolved. However, continuing studies have been approved through to March 1997 and indications are that a version of OSIRIS, slightly descoped from the original proposal, will take its place in the Rosetta payload.
Mostrar más

11 Lee mas

 Lab-made accessible full-field optical coherence tomography imaging system 

 Lab-made accessible full-field optical coherence tomography imaging system 

produced by a Koehler illuminator. Ex-vivo and in-vivo studies have been conducted in skin [11], pulmonary [12], urologic [13] and gastrointestinal tissues [14], retina and cornea [15, 16], and brain tissue [17]. Given the growing interest in research related to OCT, and the complexity involved in the development of a fully functional OCT imaging system, in this work we present a simple and easy to understand FFOCT system that is intended to be used in a context of higher education post-graduate programs in order to explain the foundations of OCT, while allowing the students to understand the concept and working mechanism of OCT. Herein, we detail the components, distances and processing techniques used to retrieve the sample information, while using optical components commonly found in most optical labs. The optical setup is built on a white-light Michelson interferometer, with a piezoelectric actuator in the reference arm in order to axially scan the sample for further volumetric imaging. By using a CCD camera, two-dimensional interferometric patterns are recorded, while the scan is performed with the piezoelectric actuator. Instead of imparting a continuous Doppler shift to the reference mirror, the envelope of the acquired interferograms —sample reflectivity— is obtained using an iterative phase-shifting algorithm where randomly generated phase shifts are used to correctly process the interferometric patterns. The optical system was successfully tested with samples of different optical properties: a metal coin and an ex-vivo insect wing of the blattodea family. Moreover, this system is readily extensible for future improvements and applications in FFOCT.
Mostrar más

11 Lee mas

Implementation of an infrared imaging system for vascular detection in the forearm and hand

Implementation of an infrared imaging system for vascular detection in the forearm and hand

The venipuncture, the catheterization and intravenous (IV) injections are some of the common procedures in the clinical practice. The location of the veins may be complex in some patients. In this paper a system able to enhance the vein distribution in a patient’s forearm in order to help, in future works, to locate the veins in a non-invasive way and accomplish the IV procedures, is described. To carry out this work a web cam was used, the filter that blocks out the infrared light has been removed and replaced for one who does not. To increase the vein detection an array of infrared LEDs (830 nm) was attached. The resulting images were processed using the adaptive histogram equa- lization and then classified by two methods, the first one based on the Fuzzy C-Means Algorithm, and the second based in a Bayesian probabilistic model. For the image acquisition, the anterior-exterior regions of the left and right forearm of each subject were considered to generate a data base. This system also has relevance in the detection of varicose veins since is able to monitor the vein dilatation.
Mostrar más

13 Lee mas

Estimating the peak auroral emission altitude from all-sky images

Estimating the peak auroral emission altitude from all-sky images

Triangulation of the aurora was performed using the Auroral Image Data Analysis (AIDA, [8]) tools adapated for ASC geometry. AIDA is a Matlab-based software package originally developed for the Auroral Large Imaging System (ALIS, [9]) located in northern Sweden. The altitude values obtained along the thin auroral arc are shown in Fig. 4 for seven time steps. The mean altitude and standard deviation calculated for each time step are indicated in pink. It can be observed that the altitude of emission varies along the arc and decreases from west to east. This trend is linked to changes in emission spatially and temporally. Figure 5 shows the difference in emission between two consecutive images. For example, the image labeled 17:33:33 UT displays the difference in intensity between the images recorded at 17:33:00 and 17:34:00 UT. In images filtered at 557.7 nm light emission intensifies between 17:34:00 and 17:35:00 UT (image at 17:34:30 UT in Fig. 5) in the eastern part of the auroral arc, but during the same time period in images filtered at 630.0 nm light emission intensifies in the western side of the images. Auroral emission is caused by high- energy (1-20 keV) particles precipitating down on the upper atmosphere where they ionize and excite the atoms and molecules present. In turn, ionization produces secondary electrons (~1 keV) that will also excite the ions. When ions return to a stable state they will emit light. The altitude of auroral emission depends on the energy of the primary electrons. High-energy electrons penetrate deeper into the atmosphere and deposit their energy at lower altitude (i.e resulting mainly in green light at 557.7 nm and blue light at 428.7 nm) and low-energy electrons deposit their energy at higher altitude (i.e. resulting mainly in red emission at 630.0 nm) [11].
Mostrar más

6 Lee mas

México, OF. a 24 Noviembre dei

México, OF. a 24 Noviembre dei

El equipo que se'utiliza para realizar las lecturas de las densidades 6ptlcas y los pesos moleculares es el Gel Doc 2000 Imaging System este aparato posee un versátil s[r]

28 Lee mas

Direct oxygen imaging in titania nanocrystals

Direct oxygen imaging in titania nanocrystals

These observations prove that the oxygen atoms in rutile twin boundaries can be directly resolved by using HAADF as well as bright field imaging. With the known oxygen and titanium column locations from both HAADF and BF images, the atomic structures of the rutile (101) and (301) twin boundaries were resolved directly from both HAADF and BF images (figures 5 and 6). In (101) twins, the twin plane consists of Ti atoms shared by two twin domains, and the sublattices of Ti atoms are mirror symmetric. The oxygen atoms around the Ti atoms are not mirror symmetric, but have 1 / 2 h 111 i displacement from the mirror symmetric position. For (301) twins, both the Ti and the O atoms in the twin plane are mirror symmetric. Our observations are consistent with the atomic structures of (101) twins and (301) twins proposed from theoretical calculation and conventional HRTEM [35–37], in which the positions of oxygen rows could not be determined because the lattice images are dominated by metal columns.
Mostrar más

10 Lee mas

Calcium Imaging in Neuron Cell Death

Calcium Imaging in Neuron Cell Death

8. Fluorescence settings have to be adjusted in each imaging setup depending on multiple factors including excitation lamp intensity in the UV range (340 and 380 nm), quality of the lens, dichroic mirror, and quality of the camera. Usually Fura2/ AM-loaded cells do not emit much light when excited at 340 nm. In those cases it may be possible to use different set- ting for each wavelength. In general, glass coverslips are required to have good light transmission in the UV. Avoid plastics that absorb UV light. If not enough signal is achieved, it is possible to increase gain, decrease offset, increase the bin- ning to 4 × 4 pixels and also the Fura2/AM loading time. 9. Binding of Ca2+ to Fura2 changes Fura2 fluorescence accord-
Mostrar más

16 Lee mas

STRAIN RATE IMAGING BY DOPPLER ULTRASOUND

STRAIN RATE IMAGING BY DOPPLER ULTRASOUND

Strain is a measure that can be applied to describe the relative deformation of objects, and was proposed for use in cardiology by Mirsky and Parmley [1]. Strain, and the temporal derivative strain rate, has been proposed for assessment of regional myocardial function. Currently, regional cardiac strain and strain rate can be acquired by magnetic resonance imaging [2], computed tomography [3] and gated single-photon emission computed tomography/positron emission tomography (SPECT/PET) [4]. Analysis of M-mode ultrasound data can also provide this information, and at a higher temporal resolution than the previous techniques. Strain by M- mode can however only be acquired for a limited number of regions of the myocardium. Methods to estimate strain and strain rate directly from the received ultrasound signal, using the cross-correlation technique, have also been presented [5-6]. These methods are however computationally intensive and are not yet implemented in commercially available equipment. Color tissue Doppler imaging is a recent ultrasound technique that provides quantitative information on the velocity of the tissue [7]. Velocity samples from the whole field of view are available simultaneously. This allows for extraction of other parameters through spatial and temporal processing of the velocity data. Strain rate and strain are examples of such parameters. This paper gives an introduction to the physical concepts of these parameters and the signal processing methods involved in estimating them.
Mostrar más

6 Lee mas

Characterization of a Virtual Array based on MEMS microphones for the analysis of acoustic sources

Characterization of a Virtual Array based on MEMS microphones for the analysis of acoustic sources

• Machinery acoustic imaging high dependence of industrial plants reverberation  Large arrays... • Acoustic images acquisition system :.[r]

52 Lee mas

El papel de la imagenologa en el diagnstico de enfermedades cardiovasculares

El papel de la imagenologa en el diagnstico de enfermedades cardiovasculares

New diagnostic imaging techniques, most of them non-invasive, have opened the possibility of biologic observations in-vivo; the results will improve therapeutic management in the acute and chronic phase of atherosclerosis. In many cases of hemodynamic evaluation of heart val- ve defects and understanding of complex con- genital heart disease invasive diagnostic proce- dures can be replaced or their examination time can be diminished. Diffusion of the newest ima- ging techniques of MRI, MDCT and EBCT on a wider scale will only be possible if there is direct collaboration between cardiologists and radiologists.
Mostrar más

7 Lee mas

TítuloUltrasound Imaging of the Abdominal Wall and Trunk Muscles in Patients with Achilles Tendinopathy versus Healthy Participants

TítuloUltrasound Imaging of the Abdominal Wall and Trunk Muscles in Patients with Achilles Tendinopathy versus Healthy Participants

Abstract: Purpose: To compare and quantify with ultrasound imaging (USI) the inter-recti distance (IRD), rectus abdominis (RA), external oblique (EO), internal oblique (IO), transversus abdominis (TrAb), and multifidus thickness and the RA and multifidus cross-sectional area (CSA) between individuals with and without chronic mid-portion Achilles tendinopathy (AT). Methods: A cross-sectional study. A sample of 143 patients were recruited and divided into two groups: A group comprised of chronic mid-portion AT (n = 71) and B group composed of healthy subjects (n = 72). The IRD, RA, EO, IO, TrAb, and multifidus thickness, as well as RA and multifidus CSA, were measured by USI. Results: USI measurements for the EO (p = 0.001), IO (p = 0.001), TrAb (p = 0.041) and RA (p = 0.001) thickness were decreased as well as IRD (p = 0.001) and multifidus thickness (p = 0.001) and CSA (p = 0.001) were increased for the tendinopathy group with respect the healthy group. Linear regression prediction models (R 2 = 0.260 − 0.494; p < 0.05) for the IRD, RA, EO, and IO thickness (R 2 = 0.494), as well as multifidus CSA and thickness were determined by weight, height, BMI and AT presence. Conclusions: EO, IO, TrAb, and RA thickness was reduced and IRD, multifidus thickness and CSA were increased in patients with AT.
Mostrar más

10 Lee mas

Brain Changes in Long Term Zen Meditators Using Proton Magnetic Resonance Spectroscopy and Diffusion Tensor Imaging: A Controlled Study

Brain Changes in Long Term Zen Meditators Using Proton Magnetic Resonance Spectroscopy and Diffusion Tensor Imaging: A Controlled Study

3: Diffusion weighted imaging (DWI) and Diffusion tensor imaging (DTI): 650 images were obtained using a single-shot, spin-echo EPI technique with a b-value of 1,000 s/mm2 for each of 25 diffusion encoding directions, TE = 94.5 ms, TR = 8,000 ms, matrix = 1286 128, field of view, 24 cm, 3-mm slice thickness with no gaps, 25 slices, number of excitations 2 and a scan time of 7.25 min. The diffusion MR data were analysed using the diffusion tensor model. After a mathematical diagonalization process, the eigenvectors and eigenvalues that describe the tensor ellipsoid were determined. Subsequently, two standard diffusion indices were derived, mean diffusivity (MD) or the Apparent Diffusion Coefficient (ADC) and the fractional anisotropy (FA) [13,32]. The ADC and FA maps were calculated off-line with the Functool software 3.1.23 in the Advantage Workstation 4.3 (General Electric Medical Systems, Milwaukee, WI) in accordance with the following procedure. Initially, images were preprocessed to remove image-to-image misregistration that arises from directional eddy currents during echo-planar readout. Directional diffusion weighted images (DWIs) were spatially registered to the b < 0 image, which was set to remove image shear, compression, and shift by an affine transform. ADC is considered quantitative with normal brain values of ADC = 0.7 6 1023 mm 2
Mostrar más

14 Lee mas

Infrared Imaging and Optical Imaging and Spectroscopy of (mostly) type I Planetary Nebulae II.

Infrared Imaging and Optical Imaging and Spectroscopy of (mostly) type I Planetary Nebulae II.

higas (2001, henceforth BJ) presented infrared imag- ing and optical imaging and spectroscopy of 14 PNe. Eleven of these were found to be type I. This is the second part of this program. Optical spectra, images in the main optical emission lines and IR images di- rected towards the detection of molecular hydrogen, were obtained for an additional 14 PNe: A 14, A 24, A 79, DeHt 3, K 3-46, K 3-91, KjPn 6, M 1-28, M 1- 57, M 3-3, M 3-5, NGC 2818, Sh 1-89, and Wray 16- 22. These were chosen from the Strasbourg-ESO Catalogue of Planetary Nebulae (Acker et al. 1992) based on relatively large intensities of [N II ] 6584 and/or [S II ] 6724 with respect to Hα. This paper is organized as follows: the experimental setup and data reduction procedures are described in § 2, ob- servations are discussed in some detail in § 3, and the last section summarizes the most significant findings. 2. OBSERVATIONS AND DATA REDUCTION
Mostrar más

22 Lee mas

Infrared imaging and optical imaging and spectroscopy of (mostly) type I Planetary Nebulae. I.

Infrared imaging and optical imaging and spectroscopy of (mostly) type I Planetary Nebulae. I.

The central region of the [N II] 6584 image is displayed in the (A) subframe, where the position where the spectrum was taken is marked with a cross. North[r]

24 Lee mas

Design of a drone based measurement system for GSM signals

Design of a drone based measurement system for GSM signals

The new system introduced protocols of digital telephony, allowing more links simultaneously in the same bandwidth. Analogue systems did not fully use the signal between the phone and the cellular network. Analogue signals could not be compressed and manipulated as easily as a digital signal. Furthermore, it was possible to integrate other services, such as SMS (Short Message Service), and a greater ability to send data from fax and modem devices. Several standards were developed:

88 Lee mas

Hyperspectral Imaging for Peach Ripening Assessment

Hyperspectral Imaging for Peach Ripening Assessment

A) First group of images corresponded to indexes or combinations of wavelengths around chlorophyll absorption peak (Ind 1 , Ind 2 , Ind 3 =R 675 /R 800 and I AD ). B) Second group are [r]

5 Lee mas

MagAO IMAGING OF LONG PERIOD OBJECTS (MILO)  I  A BENCHMARK M DWARF COMPANION EXCITING A MASSIVE PLANET AROUND THE SUN LIKE STAR HD 7449

MagAO IMAGING OF LONG PERIOD OBJECTS (MILO) I A BENCHMARK M DWARF COMPANION EXCITING A MASSIVE PLANET AROUND THE SUN LIKE STAR HD 7449

Speckle interferometry searches for substellar companions close to the star have to date resulted in null-detections ( Mason et al. 2011 ) . Using MagAO ’ s simultaneous visible and infrared imaging capabilities coupled with high Strehl ratio AO, we have detected a faint object at a projected separation of ∼ 0 54 around HD 7449. In Section 2 we describe our observations, which include both imaging at seven wavelengths from 0.63 – 2.15 μ m  and new Doppler spectroscopy, and we describe our data reduction. In Section 3 we present photometry and astrometry for the object and show that it is an M dwarf at the same distance as the primary and thus is likely the source of the long-period trend; we also constrain its mass and period from RV analysis and provide updated parameters on the known inner planet HD 7449Ab; and we use numerical N-body simulations to further constrain the architecture of the system. In Section 4 we discuss the implications of our results, compare HD 7449 to other similar systems, and conclude.
Mostrar más

12 Lee mas

Accommodation: optical function and crystalline lens imaging

Accommodation: optical function and crystalline lens imaging

The adaptive-optics set up has been extensively described in Chapter 2. The primary components of the system are a Hartmann-Shack wavefront sensor (HASO 32 OEM, Imagine Eyes) and an electromagnetic deformable mirror (MIRAO, Imagine Eyes). Illumination arises from a Super Luminescent Diode emitting at 827 nm. The system counts with a Badal optometer mounted on a motorized stage (VXM-1, Velmex) which is used both for compensating for spherical refractive error, and for inducing accommodative demands. A cold mirror behind the wavefront sensor allows inserting the accommodation stimulus, a black and white Maltese cross with eight arms in the deformable mirror path. A pupil monitoring channel, consisting of a CCD camera (TELI, Toshiba), is inserted in the system by means of a plate beam-splitter. Subjects are stabilized by means of a bite bar and aligned to the system (using an x-y-z stage) using the line of sight as a reference.
Mostrar más

148 Lee mas

Stripped gas as fuel for newly formed H II regions in the encounter between VCC 1249 and M49: a unified picture from NGVS and GUViCS

Stripped gas as fuel for newly formed H II regions in the encounter between VCC 1249 and M49: a unified picture from NGVS and GUViCS

Fig. 16. Grayscale image of M 49 showing residuals from the ELLIPSE model that best fits the azimuthally averaged isophotes in the NGVS g-band imaging (see Ferrarese et al. 2011). An extensive series of shells and filaments is apparent. A complex structural was also found by Janowiecki et al. (2010); the dashed red lines indicate the regions where these authors found shells and plumes in their residual image (here shown for comparison with those in Fig. 15). VCC 1249 is labeled in cyan, as are VCC 1199 and VCC 1192, two compact elliptical galaxies that have likely undergone tidal stripping (e.g., Cote et al. 2010). VCC 1205 shows evidence for star formation detached from the main body of the galaxy, in the direction of M 49. Yellow circles show the position of candidate UCDs (having g ≤ 21 and e ff ective radii in the range 10 ≤ R e ≤ 100 pc)
Mostrar más

19 Lee mas

Show all 10000 documents...