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Journal articles on the topic 'Techniques de projection'

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Published: 4 June 2021

Last updated: 1 February 2022

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1

Tejada, Eduardo, Rosane Minghim, and Luis Gustavo Nonato. "On Improved Projection Techniques to Support Visual Exploration of Multi-Dimensional Data Sets." Information Visualization 2, no. 4 (December 2003): 218–31. http://dx.doi.org/10.1057/palgrave.ivs.9500054.

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Projection (or dimensionality reduction) techniques have been used as a means to handling the growing dimensionality of data sets as well as providing a way to visualize information coded into point relationships. Their role is essential in data interpretation and simultaneous use of different projections and their visualizations improve data understanding and increase the level of confidence in the result. For that purpose, projections should be fast to allow multiple views of the same data set. In this work we present a novel fast technique for projecting multi-dimensional data sets into bidimensional (2D) spaces that preserves neighborhood relationships. Additionally, a new technique for improving 2D projections from multi-dimensional data is presented, that helps reduce the inherent loss of information yielded by dimensionality reduction. The results are stimulating and are presented in the form of comparative visualizations against known and new 2D projection techniques. Based on the projection improvement approach presented here, a new metric for quality of projection is also given, that matches well the visual perception of quality. We discuss the implication of using improved projections in visual exploration of large data sets and the role of interaction in visualization of projected subspaces.

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2

Siriborvornratanakul, Thitirat, and Masanori Sugimoto. "ipProjector: Designs and Techniques for Geometry-Based Interactive Applications Using a Portable Projector." International Journal of Digital Multimedia Broadcasting 2010 (2010): 1–12. http://dx.doi.org/10.1155/2010/352060.

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We propose an interactive projection system for a virtual studio setup using a single self-contained and portable projection device. The system is named ipProjector, which stands for Interactive Portable Projector. Projection allows special effects of a virtual studio to be seen by live audiences in real time. The portable device supports 360-degree shooting and projecting angles and is easy to be integrated with an existing studio setup. We focus on two fundamental requirements of the system and their implementations. First, nonintrusive projection is performed to ensure that the special effect projections and the environment analysis (for locating the target actors or objects) can be performed simultaneously in real time. Our approach uses Digital Light Processing technology, color wheel analysis, and nearest-neighbor search algorithm. Second, a paired projector-camera system is geometrically calibrated with two alternative setups. The first uses a motion sensor for real-time geometric calibration, and the second uses a beam splitter for scene-independent geometric calibration. Based on a small-scale laboratory setting, experiments were conducted to evaluate the geometric accuracy of the proposed approaches, and an application was built to demonstrate the proposed ipProjector concept. Techniques of special effect rendering are not concerned in this paper.

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Schreck, Tobias, Tatiana von Landesberger, and Sebastian Bremm. "Techniques for Precision-Based Visual Analysis of Projected Data." Information Visualization 9, no. 3 (September 2010): 181–93. http://dx.doi.org/10.1057/ivs.2010.2.

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The analysis of high-dimensional data is an important, yet inherently difficult problem. Projection techniques such as Principal Component Analysis, Multi-dimensional Scaling and Self-Organizing Map can be used to map high-dimensional data to 2D display space. However, projections typically incur a loss in information. Often, uncertainty exists regarding the precision of the projection as compared with its original data characteristics. While the output quality of these projection techniques can be discussed in terms of aggregate numeric error values, visualization is often helpful for better understanding the projection results. We address the visual assessment of projection precision by an approach integrating an appropriately designed projection precision measure directly into the projection visualization. To this end, a flexible projection precision measure is defined that allows the user to balance the degree of locality at which the measure is evaluated. Several visual mappings are designed for integrating the precision measure into the projection visualization at various levels of abstraction. The techniques are implemented in an interactive system, including methods supporting the user in finding appropriate settings of relevant parameters. We demonstrate the usefulness of the approach for visual analysis of classified and unclassified high-dimensional data sets. We show how our interactive precision quality visualization system helps to examine the preservation of original data properties in projected space.

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Marcato Junior, José, Marcus Vinícius Antunes de Moraes, and Antonio Maria Garcia Tommaselli. "EXPERIMENTAL ASSESSMENT OF TECHNIQUES FOR FISHEYE CAMERA CALIBRATION." Boletim de Ciências Geodésicas 21, no. 3 (September 2015): 637–51. http://dx.doi.org/10.1590/s1982-21702015000300036.

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Abstract:Fisheye lens cameras enable to increase the Field of View (FOV), and consequently they have been largely used in several applications like robotics. The use of this type of cameras in close-range Photogrammetry for high accuracy applications, requires rigorous calibration. The main aim of this work is to present the calibration results of a Fuji Finepix S3PRO camera with Samyang 8mm fisheye lens using rigorous mathematical models. Mathematical models based on Perspective, Stereo-graphic, Equi-distant, Orthogonal and Equi-solid-angle projections were implemented and used in the experiments. The fisheye lenses are generally designed following one of the last four models, and Bower-Samyang 8mm lens is based on Stereo-graphic projection. These models were used in combination with symmetric radial, decentering and affinity distortion models. Experiments were performed to verify which set of IOPs (Interior Orientation Parameters) presented better results to describe the camera inner geometry. Collinearity mathematical model, which is based on perspective projection, presented the less accurate results, which was expected because fisheye lenses are not designed following the perspective projection. Stereo-graphic, Equi-distant, Orthogonal and Equi-solid-angle projections presented similar results even considering that Bower-Samyang fisheye lens was built based on Stereo-graphic projection. The experimental results also demonstrated a small correlation between IOPs and EOPs (Exterior Orientation Parameters) for Bower-Samyang lens.

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5

Kosel, T. H. "Microcomputerized stereographic projection." Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 914–15. http://dx.doi.org/10.1017/s0424820100106636.

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Stereographic projection is a well-known and frequently used technique for representing crystal orientations and solving crystallographic problems. Graphical techniques for preparation of stereo projections on paper are especially time-consuming for non-cubic crystals since the angles between planes and/or directions must be calculated and depend on crystal lattice parameters. A computer program has therefore been developed which permits the construction and manipulation, in a matter of seconds, of projections of any crystal structure in any orientation. The program has applications both in research and in teaching, and runs on the Macintosh™ series of microcomputers. The purpose of this paper is simply to briefly describe the capabilities of the program for the interest of electron microscopists.Johari and Thomas described a computer program which generated stereo projections of any crystal system. Since great circles, small circles and rotation of a pole or the crystal are commonly used in stereo projection problems, Kosel developed the mathematical basis for more complete computer algorithms which could perform virtually any basic operation normally done on paper.

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6

Rouseff, Daniel, Robert P. Porter, and Terry E. Ewart. "Scattered Wave Inversion by Image Projections." Ultrasonic Imaging 11, no. 4 (October 1989): 283–304. http://dx.doi.org/10.1177/016173468901100406.

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A three-dimensional diffraction tomography algorithm based on image projections is implemented. For each view, the measured scattered field is directly backpropagated onto a single plane in the image space. The backpropagated field evaluated on the plane is defined as the image projection because it closely approximates the straight line projection of the object. The object is then reconstructed by parallel slices using conventional straight ray tomographic techniques. This approach permits practical three-dimensional reconstruction using a limited number of views. The reconstructions made with image projections are of comparable quality to ideal diffraction-limited images. By backpropagating the field prior to filtering, curved or misaligned recording surfaces can be used. The limits on the image projection technique for multiple object systems are explored. A diffuse structure is reconstructed.

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7

Silva, Claudio T., Fernando V. Paulovich, and Luis Gustavo Nonato. "User-Centered Multidimensional Projection Techniques." Computing in Science & Engineering 14, no. 4 (July 2012): 74–81. http://dx.doi.org/10.1109/mcse.2012.85.

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8

Tian, Zonglin, Xiaorui Zhai, Gijs van Steenpaal, Lingyun Yu, Evanthia Dimara, Mateus Espadoto, and Alexandru Telea. "Quantitative and Qualitative Comparison of 2D and 3D Projection Techniques for High-Dimensional Data." Information 12, no. 6 (June 3, 2021): 239. http://dx.doi.org/10.3390/info12060239.

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Projections are well-known techniques that help the visual exploration of high-dimensional data by creating depictions thereof in a low-dimensional space. While projections that target the 2D space have been studied in detail both quantitatively and qualitatively, 3D projections are far less well understood, with authors arguing both for and against the added-value of a third visual dimension. We fill this gap by first presenting a quantitative study that compares 2D and 3D projections along a rich selection of datasets, projection techniques, and quality metrics. To refine these insights, we conduct a qualitative study that compares the preference of users in exploring high-dimensional data using 2D vs. 3D projections, both without and with visual explanations. Our quantitative and qualitative findings indicate that, in general, 3D projections bring only limited added-value atop of the one provided by their 2D counterparts. However, certain 3D projection techniques can show more structure than their 2D counterparts, and can stimulate users to further exploration. All our datasets, source code, and measurements are made public for ease of replication and extension.

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9

Coimbra, Danilo B., Rafael M. Martins, Tácito TAT Neves, Alexandru C. Telea, and Fernando V. Paulovich. "Explaining three-dimensional dimensionality reduction plots." Information Visualization 15, no. 2 (September 14, 2015): 154–72. http://dx.doi.org/10.1177/1473871615600010.

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Understanding three-dimensional projections created by dimensionality reduction from high-variate datasets is very challenging. In particular, classical three-dimensional scatterplots used to display such projections do not explicitly show the relations between the projected points, the viewpoint used to visualize the projection, and the original data variables. To explore and explain such relations, we propose a set of interactive visualization techniques. First, we adapt and enhance biplots to show the data variables in the projected three-dimensional space. Next, we use a set of interactive bar chart legends to show variables that are visible from a given viewpoint and also assist users to select an optimal viewpoint to examine a desired set of variables. Finally, we propose an interactive viewpoint legend that provides an overview of the information visible in a given three-dimensional projection from all possible viewpoints. Our techniques are simple to implement and can be applied to any dimensionality reduction technique. We demonstrate our techniques on the exploration of several real-world high-dimensional datasets.

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10

Marcílio-Jr, Wilson E., Danilo M. Eler, Rogério E. Garcia, and Ives R. Venturini Pola. "Evaluation of approaches proposed to avoid overlap of markers in visualizations based on multidimensional projection techniques." Information Visualization 18, no. 4 (May 3, 2019): 426–38. http://dx.doi.org/10.1177/1473871619845093.

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Multidimensional projection techniques provide graphical representations computed based on instance similarities to enable the analysis of abstract and possibly large data sets. However, when the data set size grows these graphical representations can hardly avoid overlap among markers. To overcome this issue, while some techniques attempt to remove overlap after multidimensional projection, some projection techniques were developed considering non-overlapping constraints. In this work, we present an analysis of four overlap removal techniques and two projection techniques considering non-overlapping. The evaluation was performed according to five metrics that consider structural and similarity relations, and based on the results we provide a guide to use a technique according to the data set and analysis goals.

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11

Brunner, A. M., and Y. W. Lee. "Knot projections and Coxeter groups." Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics 56, no. 1 (February 1994): 1–16. http://dx.doi.org/10.1017/s1446788700034704.

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AbstractEvery knot admits a special projection with the property that under the projection discs in the canonical Seifert surface project disjointly. Under an isotopy, such a projection can be turned into a connected sum of what we call inseparable projections. The main result is that if there is no band in an inseparable projection with half-twisting number +1 or −1, then the projection is not a projection of the trivial knot. To prove this a non-cyclic Coxeter group is constructed as a quotient of the knot group. The construction is possibly of interest in itself. The techniques developed are applied to give a criterion to decide when an inseparable projection with 3 discs comes from the trivial knot.

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12

Carmichael, Stephen W., and Stephen A. Boppart. "Optical Projection Tomography." Microscopy Today 10, no. 5 (September 2002): 3–4. http://dx.doi.org/10.1017/s1551929500058260.

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There are many approaches to obtaining high-resolution images and three dimensional volumetric data sets, but all have limitations. Many techniques involve reconstructing volumes of information from sections, either physical sections or optical sections. Recently, James Sharpe, Ulf Ahlgren, Paul Perry, Bill Hill, Allyson Ross, Jacob Hecksher-Sørensen, Richard Baldock, and Duncan Davidson have developed an optical technique that is analogous to computed tomography (CT). Whereas clinical CT involves an X-ray source and detector rotating around the patient, optical projection tomography (OPT) has the specimen rotating within an optical pathway.

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13

Im, In-Chul, and Chang-Soo Kim. "Ottonello Projection Techniques using the Metronome." Journal of the Korea Contents Association 9, no. 12 (December 28, 2009): 730–34. http://dx.doi.org/10.5392/jkca.2009.9.12.730.

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14

Gorthi, Sai Siva, and Pramod Rastogi. "Fringe projection techniques: Whither we are?" Optics and Lasers in Engineering 48, no. 2 (February 2010): 133–40. http://dx.doi.org/10.1016/j.optlaseng.2009.09.001.

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15

Goodman, S. "Stereographic projection techniques in structural geology." Journal of African Earth Sciences 22, no. 4 (May 1996): 625. http://dx.doi.org/10.1016/0899-5362(96)83783-3.

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16

Apaydin, Fazil. "Projection and Deprojection Techniques in Rhinoplasty." Clinics in Plastic Surgery 43, no. 1 (January 2016): 151–68. http://dx.doi.org/10.1016/j.cps.2015.08.001.

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17

Neves, Tácito TAT, Samuel G. Fadel, Gladys M. Hilasaca, Francisco M. Fatore, and Fernando V. Paulovich. "UPDis: A user-assisted projection technique for distance information." Information Visualization 17, no. 4 (April 12, 2017): 269–81. http://dx.doi.org/10.1177/1473871617700683.

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Multidimensional projection techniques have become essential analytical tools. Typically, they map data from a high-dimensional space into a low-dimensional visual space, preserving distance or neighborhood structures on the produced layout. Despite the advances, with faster and highly precise techniques, existing methods still carry deficiencies that impair their use as exploratory tools. An example is the mismatching that can occur between what the user considers similar/dissimilar and what is conveyed by the visual representation. Recently, a class of projection techniques aims at addressing this limitation, allowing users to control the projection process by changing the distance relationships using small data samples. Among such methods, Local Affine Multidimensional Projection has proved to be the state-of-the-art regarding the effectiveness of user intervention. Although Local Affine Multidimensional Projection has attained a relative success, it is limited to certain application domains. Since it relies on feature vector representations with data instances described by vectors embedded into a Euclidean space, scenarios that offer only distance information or a distance function cannot be handled. In this article, we present a novel multidimensional projection technique, called User-assisted Projection Technique for Distance Information, which takes advantage of the solid mathematical framework provided by Local Affine Multidimensional Projection, adapting it to scenarios where only distance information or a distance function is available. The results show that User-assisted Projection Technique for Distance Information is as fast, accurate, robust, and flexible as the existing state-of-the-art techniques, enabling the application of the refined user control provided by Local Affine Multidimensional Projection on domains not previously covered. Its versatility is illustrated in an application that involves the organization of book collections that employs an external source of information for the recommendation of new readings.

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18

Murstein, Bernard I., and Susan Mathes. "Projection on Projective Techniques = Pathology: The Problem That Is Not Being Addressed." Journal of Personality Assessment 66, no. 2 (April 1996): 337–49. http://dx.doi.org/10.1207/s15327752jpa6602_11.

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19

Comi, Alice, Nicole Bischof, and Martin J. Eppler. "Beyond projection: using collaborative visualization to conduct qualitative interviews." Qualitative Research in Organizations and Management: An International Journal 9, no. 2 (June 3, 2014): 110–33. http://dx.doi.org/10.1108/qrom-05-2012-1074.

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Purpose – The purpose of this paper is to argue for the reflective use of visual techniques in qualitative inter-viewing and suggests using visuals not only as projective techniques to elicit answers, but also as facilitation techniques throughout the interview process. Design/methodology/approach – By reflecting on their own research projects in organization and management studies, the authors develop a practical approach to visual interviewing – making use of both projective and facilitation techniques. The paper concludes by discussing the limitations of visualization techniques, and suggesting directions for future research on visually enhanced interviewing. Findings – The integration of projective and facilitation techniques enables the interviewer to build rapport with the respondent(s), and to elicit deeper answers by providing cognitive stimulation. In the course of the interview, such an integrative approach brings along further advantages, most notably focusing attention, maintaining interaction, and fostering the co-construction of knowledge between the interviewer and the interviewee(s). Originality/value – This paper is reflective of what is currently occurring in the field of qualitative interviewing, and presents a practical approach for the integration of visual projection and facilitation in qualitative interviews.

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20

Chen, Xiaoyun, Mengzhen Liao, and Xianbao Ye. "Projection subspace clustering." Journal of Algorithms & Computational Technology 11, no. 3 (May 2, 2017): 224–33. http://dx.doi.org/10.1177/1748301817707321.

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Gene expression data is a kind of high dimension and small sample size data. The clustering accuracy of conventional clustering techniques is lower on gene expression data due to its high dimension. Because some subspace segmentation approaches can be better applied in the high-dimensional space, three new subspace clustering models for gene expression data sets are proposed in this work. The proposed projection subspace clustering models have projection sparse subspace clustering, projection low-rank representation subspace clustering and projection least-squares regression subspace clustering which combine projection technique with sparse subspace clustering, low-rank representation and least-square regression, respectively. In order to compute the inner product in the high-dimensional space, the kernel function is used to the projection subspace clustering models. The experimental results on six gene expression data sets show these models are effective.

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21

Quan, C., W. Chen, and C. J. Tay. "Phase-retrieval techniques in fringe-projection profilometry." Optics and Lasers in Engineering 48, no. 2 (February 2010): 235–43. http://dx.doi.org/10.1016/j.optlaseng.2009.06.013.

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22

Dobe, J., S. P. Ivanova, R. V. Jolos, and R. Pedrosa. "Projection operator in the boson expansion techniques." Physical Review C 41, no. 4 (April 1, 1990): 1840–44. http://dx.doi.org/10.1103/physrevc.41.1840.

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23

Pagès, J., and J. Salvi. "Coded light projection techniques for 3D reconstruction." J3eA 4 (2005): 001. http://dx.doi.org/10.1051/bib-j3ea:2005801.

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24

Galgon, Martin, Lukas Krämer, and Bruno Lang. "Improving projection-based eigensolvers via adaptive techniques." Numerical Linear Algebra with Applications 25, no. 1 (October 20, 2017): e2124. http://dx.doi.org/10.1002/nla.2124.

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25

Glover, Gary H., and Douglas C. Noll. "Consistent projection reconstruction (CPR) techniques for MRI." Magnetic Resonance in Medicine 29, no. 3 (March 1993): 345–51. http://dx.doi.org/10.1002/mrm.1910290310.

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26

Padhye, Snehal, David Messinger, and James A. Ferwerda. "A practitioner’s guide to fringe projection profilometry." Archiving Conference 2021, no. 1 (June 18, 2021): 56–60. http://dx.doi.org/10.2352/issn.2168-3204.2021.1.0.13.

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Many techniques exist for 3D digitization of cultural heritage objects. Paintings, manuscripts, and other near-planar objects are especially challenging to digitize because of their minute surface variations. Of the existing techniques, fringe projection profilometry (FPP) is one of the most promising approaches for measuring the surface shape of such objects. In practical implementations of FPP, one needs to understand and control various sources of error due to system hardware and environmental conditions. It is difficult to find information on this in one place in the literature, which discourages application of the technique. In this paper we present a practitioner’s guide to phase-shifting fringe projection profilometry that covers critical but often omitted implementation details required for successful application of the technique.

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27

Rouseff, Daniel, Leung Tsang, and Robert P. Porter. "Diffraction Tomography by a Method of Image Projections." Ultrasonic Imaging 10, no. 3 (July 1988): 204–19. http://dx.doi.org/10.1177/016173468801000304.

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A method of three-dimensional diffraction tomography based on image projections is derived. Inversion methods based on projections generally are inaccurate due to the spreading nature of the scattered wave. By backpropagating the field onto a single plane in the image region, diffraction effects are reduced and a projection of the weakly scattering object is generated. Consequently, conventional X-ray inversion techniques may be used to image the object The relationship between the backpropagated field and the projection is derived both for high frequency incident waves and low spatial frequency scatterers. The generalized image kernel allows the use of curved or misaligned recording surfaces. Numerical results are included.

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28

Sant'Anna, Isabela de Castro, Gabi Nunes Silva, Vinicius Quintão Carneiro, Daiana Salles Pontes, Moyses Nascimento, and Cosme Damião Cruz. "Comparison of projection of distance techniques for genetic diversity studies." Acta Scientiarum. Agronomy 42 (November 20, 2019): e42483. http://dx.doi.org/10.4025/actasciagron.v42i1.42483.

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The objective of this study was to compare different graphical dispersion analysis techniques in two- or three-dimensional planes. In this study, the data from different published works were used in order to determine the best methodology for analyzing the genetic diversity of different species. In this study, efficiency is measured by the amount of original distance absorbed by the projection of distances technique, which in the case of major components is equal to the amount of total variation originally available and retained by the principal components used for dispersion purposes. The projection of dissimilarity measurement technique, principal component analysis (PCA), and principal coordinate analysis (PCoA) were used. Considering the analysis by means of three orthogonal axes, the graphical dispersion efficiency was 82.22 for PCA, 87.22 for PCoA, and 85.25 for the projection of distances technique. For the 2D analysis, considering the two main axes, the mean dispersion efficiency was 69.90 for the PCA, 75.06 for the projection technique, and 78.16 for PCoA. Considering the studies carried out with experimental data of six different species, it is concluded that the principal coordinate analysis is superior.

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Biasini, M., and G. Kontrym-Sznajd. "What Else for Improvement of Reconstructed Densities?" Materials Science Forum 666 (December 2010): 147–50. http://dx.doi.org/10.4028/www.scientific.net/msf.666.147.

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Reconstruction techniques, belonging to two different categories (series expansion and transform methods), are compared with regard to their applicability to line projections of a model density. It is demonstrated that in the case of this model the algebraic technique gives much better results than the filtered back projection (FBP) algorithm. However, it could not be a case for real data where a region of densities to be considered is very large comparing to the modelled one. In this connection we propose a new way of dealing with two-dimensional (2D) angular correlation of annihilation radiation (ACAR) data. Such a treatment, proposed for all reconstruction techniques, allows to improve reconstructed densities and filters the experimental noise.

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Rivard, Denis, and Malcolm G. Foy. "An Analysis of Errors in Catch Projections for Canadian Atlantic Fish Stocks." Canadian Journal of Fisheries and Aquatic Sciences 44, no. 5 (May 1, 1987): 967–81. http://dx.doi.org/10.1139/f87-115.

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Two techniques were used to identify and evaluate the components of error inherent in the catch projection method used in the assessment of Canadian Atlantic fish stocks. Firstly, a retrospective analysis was used to evaluate, for the projections made in 1979 and 1981, the impact of the actual error made in input variables such as catch-at-age, mean weight-at-age, recruitment, and stock size. Secondly, the variance of projections was estimated from the variance of input variables. From the retrospective analysis, the principal causes of error in catch projections were identified as the estimation of stock size, as well as the estimation and forecast of fishing mortalities for the projection years. The difference between actual catch and assumed catch for the first year of a 2-yr projection did not appear to be a major source of bias for catch projections. The coefficients of variation of the catch projected at F0.1 were estimated as follows: 15–20% for the projections of Atlantic cod (Gadus morhua) catches; 25–50% for those of haddock (Melanogrammus aeglefinus); 28% for those of pollock (Pollachius virens); 16% for those of redfish (Sebastes sp.); and 35–42% for those of herring (Clupea harengus). The uncertainties associated with abundance estimates for prerecruited age-groups and estimates of stock size emerged as key factors in the projections. Also important was the effect of uncertainties associated with the forecast of reference fishing mortalities (partial recruitment coefficients × F0.1) for the projection period, e.g. uncertainties resulting from changes in fish catchability, in fleet behavior, and in fishing patterns.

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Delgado-Gómez, David, and Diego Ruiz-Hernández. "A One-Sample per Individual Face Recognition Algorithm Based on Multiple One-Dimensional Projection Lines." International Journal of Pattern Recognition and Artificial Intelligence 31, no. 07 (April 10, 2017): 1756012. http://dx.doi.org/10.1142/s0218001417560122.

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This paper proposes a novel approach for face recognition when only one sample per individual is available. The proposed technique, referred to as MODPL, determines a one-dimensional projection line for each individual in the dataset. Each of these lines discriminates the corresponding individual with respect to the other people in the database. The vector consisting on the projections of the individual’s raw data on the different projections lines provides an excellent characterization of the individual. Results obtained using the XM2VTS database show that the proposed technique is capable of achieving classification rates similar to the ones obtained by means of the Uniform-pursuit algorithm and at least 5% higher than other currently used techniques that deal with the one sample problem. Two additional sets of experiments were conducted on the BioID and AR databases, where the proposed algorithm showed a performance similar to the state-of-the-art algorithms. Moreover, the proposed technique allows the visualization of the most discriminative features of the individuals.

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32

Miniati, Kadek, Gusti Ngurah Sutapa, and I. Wayan Balik Sudarsana. "UJI KELAYAKAN PESAWAT SINAR-X TERHADAP PROYEKSI PA (POSTERO-ANTERIOR) DAN LAT (LATERAL) PADA TEKNIK PEMERIKSAAN FOTO THORAX." BULETIN FISIKA 18, no. 1 (February 1, 2017): 27. http://dx.doi.org/10.24843/bf.2017.v18.i01.p05.

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Research has been conducted to determine feasibility test of the X-ray planePA and LAT projections on chest x-ray techniques. The study using a water phantom object as a substitute for patients with variations in interval distance ofthe 100-180 cm. Measurement of radiation dose X-rays performed five repetitions , measurable doses had be read on the device electrometer. Exposition factors to the PA projection using a tube voltage of 75 kV, current and time of 3,2 mAs, the irradiation field areaof (30 x 30) cm2.For the LAT projection tube voltage of 80 kV, current and time of 6,3 mAs, and the irradiation field area of (20 x 30) cm2. It the study of the radiation dose X-ray plane projection PA and LAT is optimal is below the limit value at the level of dosage guidelines BAPETEN No 08 of 2011. Obtained PA projections are below the value of 0,4 mGy while LAT projection is below the value of 1,5 mGy. The radiation dose X-rays plane using a variation of 100-180 cm distance is still below the dose limit values ??, thus meeting the objectives anssurance quality and quality control.

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Asaki, T. J., E. M. Bollt, and K. R. Vixie. "Sparse Radiographic Tomography and System Identification Imaging from Single View, Multiple Time Sample Density Plots." Computational Methods in Applied Mathematics 6, no. 4 (2006): 354–66. http://dx.doi.org/10.2478/cmam-2006-0022.

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Abstract Tomography is a classic inverse problem in which multiple density projections of an object are processed to infer some approximation of the original. We consider the highly sparse inverse problem of single angle projection, but seek to reduce the ambiguity through multiple time observations in a dynamic system of known or partially known dynamics. In this work we solve the planar problem by optimization techniques based on a gradient-free multi-directional search algorithm to minimize our nonlinear functional. We demonstrate convincingly successful numerical examples to support our relatively simple technique.

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Hammock, Dugan, Fang Fang, and Klee Irwin. "Quasicrystal Tilings in Three Dimensions and Their Empires." Crystals 8, no. 10 (September 20, 2018): 370. http://dx.doi.org/10.3390/cryst8100370.

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The projection method for constructing quasiperiodic tilings from a higher dimensional lattice provides a useful context for computing a quasicrystal’s vertex configurations, frequencies, and empires (forced tiles). We review the projection method within the framework of the dual relationship between the Delaunay and Voronoi cell complexes of the lattice being projected. We describe a new method for calculating empires (forced tiles) which also borrows from the dualisation formalism and which generalizes to tilings generated projections of non-cubic lattices. These techniques were used to compute the vertex configurations, frequencies and empires of icosahedral quasicrystals obtained as a projections of the D 6 and Z 6 lattices to R 3 and we present our analyses. We discuss the implications of this new generalization.

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Ordon, Andrew P. "Correction of the Overprojected Nasal Tip." American Journal of Cosmetic Surgery 11, no. 3 (September 1994): 195–202. http://dx.doi.org/10.1177/074880689401100309.

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Our approach to decrease tip projection is presented. These techniques may be applied to the three degrees of overprojection, namely the relative, moderate, and ultraprojecting tip. We feel that our techniques will apply to all clinical situations where decrease in projection is desirable. Our concepts have emerged from review of previous techniques and have evolved over our past 1000 rhinoplasties. Excess nasal septum including the nasal spine area, redundancy in the feet of the medial crura, and soft tissue excess may all contribute to the overprojecting tip. However it is excess in the lower lateral cartilage complex, specifically in the medial crus, that requires the most surgical attention and alteration. Our technique in reducing the medial crus to decrease projection is patterned after the Universal Tip Technique described by Parkes and Kanodia. This endonasal technique utilizes a laterally based unipedicled lower lateral cartilage flap, which is freely rotational, but does not violate the continuity of the vestibular skin. With development of our laterally based unipedicle lower lateral cartilage flap, the number of millimeters desired to reduce the projection is removed from the medial crus and eliminated in the final adjustment of tip projection and, in this way, decreases tip projection. In the moderate case, approximately 3 mm of medial crus is excised. In the more severe or ultraprojecting tip, ≥5 is removed from the medial crus. In extreme overprojecting noses, excess soft tissue is addressed by excision of an ellipse of mucosa at the intercartilaginous incision at the septal angle. In the ultraprojecting tip, in addition to resection of redundant cephalic lower lateral cartilage and a ≥5-mm segment of medial crus, it may be necessary to also resect the lateralmost extension of the lower lateral cartilage, the feet of the medial crura, and alar bases. Septal modification, including an inferior strip resection of septum including the nasal spine, may also contribute to decreasing projection. We have found this technique to be effective and predictable over the last 10 years.

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Čížek, Jiří, and Francine Vinette. "The application of inner projection technique to many electron systems as compared with the coupled cluster expansion. A study of the Pariser-Parr-Pople model of the benzene molecule." Collection of Czechoslovak Chemical Communications 53, no. 9 (1988): 1910–18. http://dx.doi.org/10.1135/cccc19881910.

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The technique of inner projection is used for the first time in a chemical context, namely for the study of the ground state energy of the Pariser-Parr-Pople model of the benzene molecule. The lower bound for the energy is calculated for three types of parametrization. These results are compared with the “exact” energies which are obtained from full configuration interaction. It is shown that the inner projection technique provides very good lower bounds for the energy. In addition, we compare these inner projection results with those obtained by other approximative techniques, namely with the results of the Coupled Pair Many Electron Theory. A discussion of the application of the method of intermediate hamiltonians and the inner projection technique is also included.

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Viji Amutha Mary, A. "A Random Projection Approach to Strengthen the Privacy Level of Medical Images." Journal of Computational and Theoretical Nanoscience 16, no. 8 (August 1, 2019): 3219–21. http://dx.doi.org/10.1166/jctn.2019.8165.

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All our day’s work in this world of science is done with useful data. These useful data or information is extracted from raw facts. From the information, knowledge is gained. This knowledge is used by the customers for beneficial outcome. Here comes the concept of data mining. An important query arises as how to preserve these data. This concept is called as Privacy Preserving with Data Mining (PPDM). Many PPDM techniques are available to protect the data. The PPDM technique is useful in fields like medicine, forensics, defence, etc to preserve the confidential data. The existing techniques protect the secret data either by perturbing or by hiding them. Moreover, most of the techniques focus only on the numerical data. Very few perturbation techniques like translation, multiplicative and rotation perturb the images. But these techniques are very easily attacked by third parties since the transformation is a linear one. The Research Work aims to overcome the drawbacks of the existing perturbation techniques. The main objective of the Research Work is to improve the privacy level of the images by implementing a Random Projection (RP) technique. The remarkable features and benefits of the RP technique are pinpointed.

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Zhu, Jingyi, and James Sethian. "Projection methods coupled to level set interface techniques." Journal of Computational Physics 102, no. 1 (September 1992): 128–38. http://dx.doi.org/10.1016/s0021-9991(05)80011-7.

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Cadou, J. M., N. Damil, M. Potier-Ferry, and B. Braikat. "Projection techniques to improve high-order iterative correctors." Finite Elements in Analysis and Design 41, no. 3 (December 2004): 285–309. http://dx.doi.org/10.1016/j.finel.2004.04.006.

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Vernier, E. F., R. Garcia, I. P. da Silva, J. L. D. Comba, and A. C. Telea. "Quantitative Evaluation of Time‐Dependent Multidimensional Projection Techniques." Computer Graphics Forum 39, no. 3 (June 2020): 241–52. http://dx.doi.org/10.1111/cgf.13977.

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Kye, Hee-Won, and Jun-Ho Kim. "Acceleration techniques for GPGPU-based Maximum Intensity Projection." Journal of Korea Multimedia Society 14, no. 8 (August 31, 2011): 981–91. http://dx.doi.org/10.9717/kmms.2011.14.8.981.

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Mooi Choo Chuah. "Analysis of networks of queues via projection techniques." IEEE Transactions on Automatic Control 39, no. 8 (1994): 1588–99. http://dx.doi.org/10.1109/9.310032.

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Daszykowski, Michał. "From projection pursuit to other unsupervised chemometric techniques." Journal of Chemometrics 21, no. 7-9 (2007): 270–79. http://dx.doi.org/10.1002/cem.1044.

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Martins, A. M., and J. T. Mendonça. "Study of wave interaction using projection operator techniques." Transport Theory and Statistical Physics 16, no. 2-3 (March 1987): 297–310. http://dx.doi.org/10.1080/00411458708204666.

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Kajfosz, A. "The projection-like techniques for Wigner's distribution function." Czechoslovak Journal of Physics 37, no. 12 (December 1987): 1360–68. http://dx.doi.org/10.1007/bf01595669.

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Peřina, Jan. "On the equivalence of some projection operator techniques." Physica A: Statistical Mechanics and its Applications 214, no. 2 (March 1995): 309–18. http://dx.doi.org/10.1016/0378-4371(94)00267-w.

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Zhu, Jingyi, and James Sethian. "Projection methods coupled to level set interface techniques." Journal of Computational Physics 100, no. 2 (June 1992): 435. http://dx.doi.org/10.1016/0021-9991(92)90267-3.

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Gómez Manzanares, Ángela, Anto J. Benítez, and Juan Carlos Martínez Antón. "Virtual Restoration and Visualization Changes through Light: A Review." Heritage 3, no. 4 (November 17, 2020): 1373–84. http://dx.doi.org/10.3390/heritage3040076.

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The virtual modification of the appearance of an object using lighting technologies has become very important in recent years, since the projection of light on an object allows us to alter its appearance in a virtual and reversible way. Considering the limitation of non-contact when analysing a work of art, these optical techniques have been used in fields of restoration of cultural heritage, allowing us to visualize the work as it was conceived by its author, after a process of acquisition and treatment of the image. Furthermore, the technique of altering the appearance of objects through the projection of light has been used in projects with artistic or even educational purposes. This review has treated the main studies of light projection as a technique to alter the appearance of objects, emphasizing the calibration methods used in each study, taking into account the importance of a correct calibration between devices to carry out this technology. In addition, since the described technique consists of projecting light, and one of the applications is related to cultural heritage, those studies that carry out the design and optimization of lighting systems will be described for a correct appreciation of the works of art, without altering its state of conservation.

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Wu, Li Ming, Qi Li, and Si Cheng Chen. "Research of Multi-Touch Projection Camera Interaction Techniques Based on SOPC." Applied Mechanics and Materials 543-547 (March 2014): 784–87. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.784.

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Projection-camera interaction is a human-computer interaction technology which uses projector-camera as input-output devices, and combined with human movement as interactive mode. Introducting radial distortion and tangential distortion of lens to projection-geometric calibrate the camera system, the platform is used the Xilinx main processor Virtex-4 FX experimental box to building a projection-camera interactive implementation platform, and used the Baum-Welch algorithm which based on hidden Markov model for training gesture.

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Kartika Sari, Nina. "Teknik Persuasif dalam Buku Sukses Tanpa Gelar Karya Andrias Harefa." GERAM 6, no. 1 (July 7, 2018): 72–82. http://dx.doi.org/10.25299/geram.2018.vol6(1).1799.

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This re search entitled persuasive techniques in a sussessful book without the title of Andrias Harefa work. The problem of research, how persuasive techniques, rationalization, identification, suggestion, conformity, compensation, replacement and projection in a successful book without a degree of work Andrias Harefa? Aims to describe, analyze, and intepret persuasive techniques, rationalization, identification, suggestion, conformity, compensation, replacement and projection in a successful book without the title of work Andrias Harefa. This research uses the theory proposed by Gorys Keraf 2004, using descriptive method. Data and data sources in this study is the contents of a successful book without the title Andrias Harefa work in 2005. This research method descriptive method, research type that is literature, and research approach that is qualitative. Data collection techniques used by the author is to classify data, analyze data, interpret data, and draw conclusions. Result of research about persuasive technique in success book without title of work of Andrias Harefa found existence persuasive technique counted 47 data or equal to 100% of them, rationalization used Andrias Harefa equal to 3 data or egual to 7%, identification used Andrias Harefa 31 data or equivalent to 67%, the suggestion used Andrias Harefa of 3 data or equaivalent to 7 %, the conformity used Andrias Harefa as much as 3 data or equivalent to 7%, replacement used Andrias Harefaas many as 4 data or equivalent to 9%, the projection used Andrias Harefa as much as 1 data or equivalent to 2%. Thus it can be concluded that the persuasive technique used by Andrias Harefa in a successful book without a title is more dominant using the technique of persuasive identification because a successful book without the title of work Andrias Harefa tends to use spsesial and interesting things to influence the reader, followed by replacemet, rationalization, suggestion, conformity, compensation, and projection.

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