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[en] The study was to analyze on the hard and soft tissue profiles in mixed dentition. The subject consisted of 100 males and 100 females from 9 to 12 years of age and with a normal occlusion and acceptable profiles. On the bases of SnH line and SnV line, the author traced all the cephalograms and calculated the mean value and standard deviation in each measuring category and evaluated the sexual difference, the proper limit of development. The obtained results were as follows; 1. Individual variations of the lower facial part were larger the upper facial part in depth and height. 2. Sexual difference of lower facial part was significant in depth and height. 3. All the measured values to the SnH and SnV line were larger in male than in female but revealed resemblance in the profilogram. 4. The measured values of the region of nose, upper lip and point A showed stable tendency.
[en] Mahalanobis distance Δ"2 values are commonly in the range of 0 to +∞ where higher values represent greater distance between class means or points. The increase in Mahalanobis distance is unbounded as the distance multiply. To certain extend, the unbounded distance values pose difficulties in the evaluation and decision for instance in the sensors closeness test. This paper proposes an approach to [0, 1] bounded Mahalanobis distance Δ"2 that enable researcher to easily perform sensors closeness test. The experimental data of four different types of rice based on three different electronic nose sensors namely InSniff, PEN3, and Cyranose320 were analyzed and sensor closeness test seems successfully performed within the [0, 1] bound
[en] Dissecting the genetic basis of adaptive traits is key to our understanding of evolutionary processes. A major and essential step in the study of evolutionary genetics is drawing link between genotype and phenotype, which depends on the difficult process of defining the phenotype at different levels, from functional to organismal. Visual pigments are a key component of the visual system and their evolution could also provide important clues on the evolution of visual sensory system in response to sexual and natural selection. As a system in which genotype can be linked to phenotype. I will use visual pigments and color vision, particularly in birds, as a case of a complex phenotype. I aim to emphasize the difficulties in drawing the genotype-phenotype relationship for complex phenotypes and to highlight the challenges of doing so for color vision. The use of vision-based receiver models to quantify animal colors and patterns is increasingly important in many fields of evolutionary research, spanning studies of mate choice, predation, camouflage and sensory ecology. Given these models impact on evolution and ecology, it is important to provide other researchers with the opportunity to better understand animal vision and the corresponding advantages and limitations of these models.
[en] The electrooculogram signals are very important at extracting information about detection of directional eye movements. Therefore, in this study, we propose a new intelligent detection model involving an artificial neural network for the eye movements based on the electrooculogram signals. In addition to conventional eye movements, our model also involves the detection of tic and blinking of an eye. We extract only two features from the electrooculogram signals, and use them as inputs for a feed-forwarded artificial neural network. We develop a new approach to compute these two features, which we call it as a movement range. The results suggest that the proposed model have a potential to become a new tool to determine the directional eye movements accurately
[en] Although a compensation device can correct aberrations of human eyes, the effect will be degraded by its misalignment, especially for high-order aberration correction. We calculate the positioning tolerance of correction device for high-order aberrations, and within what degree the correcting effect is better than low-order aberration (defocus and astigmatism) correction. With fixed certain misalignment within the positioning tolerance, we calculate the residual wavefront rms aberration of the first-6 to first-35 terms along with the 3rd-5th terms of aberrations corrected, and the combined first-13 terms of aberrations are also studied under the same quantity of misalignment. However, the correction effect of high-order aberrations does not meliorate along with the increase of the high-order terms under some misalignment, moreover, some simple combined terms correction can achieve similar result as complex combinations. These results suggest that it is unnecessary to correct too much the terms of high-order aberrations which are difficult to accomplish in practice, and gives confidence to correct high-order aberrations out of the laboratory
[en] It discusses a video-based head-fixed eye tracker with high precision. While measuring the coordinates associated with eye-gaze, a subject places his mandibular on a support and keeps his head fixed. Meanwhile, a camera is used to capture images of the subject's left or right eye. The subject's gaze point fallen on a computer screen can be determined according to the relative position of the pupil and Purkinje reflex in an eye image. This paper presents not only the mathematical model used to measure the coordinates associated with eye gaze, but also the methods used to recognize the pupil and Purkinje reflex in an eye image. To recognize the pupil and Purkinje reflex in an eye image, the eye image is firstly converted into a binary image, and then the method proposed by F. Chang et al is used to label the components in the binary image. On this basis, the pupil and Purkinje reflex in an eye image are recognized based on the area and shape of the components. This paper also presents some experimental results, and the experimental results show that the maximal average error of the experimental apparatus is 0.62 degree. (authors)
[en] A responsibility of the Laser Safety Officer (LSO) is to perform laser audits. The American National Standard Z136.1 Safe Use of Lasers references this requirement through several sections. One such reference is Section 220.127.116.11, Safety Features Audits, ''The LSO shall ensure that the safety features of the laser installation facilities and laser equipment are audited periodically to assure proper operation''. The composition, frequency and rigor of that inspection/audit rests in the hands of the LSO. A common practice for institutions is to develop laser audit checklists or survey forms It is common for audit findings from one inspector or inspection to the next to vary even when reviewing the same material. How often has one heard a comment, ''well this area has been inspected several times over the years and no one ever said this or that was a problem before''. A great number of audit items, and therefore findings, are subjective because they are based on the experience and interest of the auditor to particular items on the checklist. Beam block usage, to one set of eyes might be completely adequate, while to another, inadequate. In order to provide consistency, the Laser Safety Office of the National Ignition Facility Directorate has established criteria for a number of items found on the typical laser safety audit form. The criteria are distributed to laser users. It serves two broad purposes; first, it gives the user an expectation of what will be reviewed by an auditor. Second, it is an opportunity to explain audit items to the laser user and thus the reasons for some of these items, such as labelling of beam blocks
[en] The purpose of this investigation was to locate the plane of the image layer on the panoramic machine relative to a specific point on the machine. In the study of the central plane of the image layer of panoramic radiograph, using the Morrita Company PANEX-EC a series of 33 exposures were taken with the 4-5 experimental pins placed in the holes of the plastic model plate, then evaluated by human eye. The author analyzed the central plane of the image layer by Mitutoy-A-221 and calculated horizontal and vertical magnification ratio in central plane of the image layer determined experimentally. The results were as follows: 1. The location of the central plane of the image layer determined experimentally was to lateral compared with manufactural central plane. 2. Horizontal magnification ratio in the central plane of image layer determined experimentally was 9.25%. 3. Vertical magnification ratio in the central plane of the image layer determined experimentally was 9.17%.
[en] Macular telangiectasia type 2 (Mac Tel 2) is a bilateral disease of unknown cause with characteristic changes of the retinal vasculature. To the best of our knowledge, we could not find any reported cases of Mac Tel 2 with retinal arterial macroaneurysm (RAM). Our aim is to report a case of Mac Tel 2 with RAM.
[en] A remote maintenance support system using optical see-through AR has been developed to keep safety and reliability in preparation for old experts' retirement. It enables plant workers to collaborate with a remote expert (supervisor) by using a wearable computer, an optical see-through AR (Augmented Reality) technology and eye-gaze information. The optical see-through AR enables a user to see the real world through a transparent display and it contributes to keeping safety of plant workers and acquiring detail information of machines. On the contrary, the registration between computer-generated objects and the real world is difficult, so we developed a method to correct the geometrical consistency for practical use of optical see-through AR. The developed method has two steps: (1) detection of the shift amount of HMD by the eye camera image and (2) adjustment of the display position on the HMD screen. This method made it possible to allow user's moving and physical shift of HMD, so it is capable of wide application to practical works