268 research outputs found
Questionnaires from the National Health Interview Survey, 1985-89
No full textThis series report includes the questions used in the National Health Interview Survey from 1980 to 1984. The report contains the basic health and demographic questionnaires and current health topic queWonnaires.By Michele M. Chyba, Division of Health Intetview Statistics, and Linda R. Washington, Division of Data Services.Includes bibliographical references (p. 289).19931116
Reconstruction of tubular structures from 2.5D point clouds: A mesophotic gorgonian coral case study
No full textA method for the surface reconstruction of 3D tubular branched structures characterized by low informative point clouds (i.e., 2.5D) is proposed. These specific clouds can arise when using photogrammetry techniques on complex subjects in challenging scanning environments (e.g., underwater gorgonian coral at mesophotic depths). The core idea behind the proposed Sphere Skeleton Approach (SSA) is to approximate the assumed tubular shapes via merged spheres having variable radii and centered in the points of the medial skeleton. To assess the generality and robustness of the proposed SSA, additional experiments have been conducted on 2.5D point clouds that were synthetically generated from 3D model benchmarks. Hausdorff distances between the target and the reconstructed 3D models are used to quantitatively compare the SSA performances to a classical meshing algorithm. Early results highlight the capability to outperform existing approaches in reconstructing objects from 2.5D clouds.
References
Agisoft. 2021. url: https://www.agisoft.com/
M. Berger, J. A. Levine, L. G. Nonato, G. Taubin, and C. T. Silva. A benchmark for surface reconstruction. ACM Trans. Graph. 32.2 (2013), pp. 1–17. doi: 10.1145/2451236.2451246
M. Berger, A. Tagliasacchi, L. M. Seversky, P. Alliez, G. Guennebaud, J. A. Levine, A. Sharf, and C. T. Silva. A survey of surface reconstruction from point clouds. Comput. Graph. Forum. Vol. 36. 1. 2017, pp. 301–329. doi: 10.1111/cgf.12802
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J. F. Blinn. A generalization of algebraic surface drawing. ACM Trans. Graph. 1.3 (1982), pp. 235–256. doi: 10.1145/357306.357310
P. Cignoni, M. Callieri, M. Corsini, M. Dellepiane, F. Ganovelli, and G. Ranzuglia. Meshlab: an open-source mesh processing tool. Eurographics Italian Chapter Conference. Ed. by V. Scarano,
R. De Chiara, and U. Erra. 2008, pp. 129–136. doi: 10.2312/LocalChapterEvents/ItalChap/ItalianChapConf2008/129-136
H. Huang, S. Wu, D. Cohen-Or, M. Gong, H. Zhang, G. Li, and B. Chen. L1-medial skeleton of point cloud. ACM Trans. Graph. 32.4 (2013), pp. 1–8. doi: 10.1145/2461912.2461913
Y.-H. Jin and W.-H. Lee. Fast cylinder shape matching using random sample consensus in large scale point cloud. Appl. Sci. 9.5 (2019), p. 974. doi: 10.3390/app9050974
L. Liu, D. Ceylan, C. Lin, W. Wang, and N. J. Mitra. Image-based reconstruction of wire art. ACM Trans. Graph. 36.4 (2017), pp. 1–11. doi: 10.1145/3072959.3073682
B. B. Mandelbrot. The fractal geometry of nature. Vol. 1. W. H. Freeman New York, 1982. url: https://www.nhbs.com/the-fractal-geometry-of-nature-book
J. Mei, L. Zhang, S. Wu, Z. Wang, and L. Zhang. 3D tree modeling from incomplete point clouds via optimization and L1-MST. Int. J. Geo. Inf. Sci. 31.5 (2017), pp. 999–1021. doi: 10.1080/13658816.2016.1264075
S. J. Rowley, T. E. Roberts, R. R. Coleman, H. L. Spalding, E. Joseph, and M. K. L. Dorricott. Pohnpei, Federated States of Micronesia. Mesophotic Coral Ecosystems. Springer, 2019, pp. 301–320. doi: 10.1007/978-3-319-92735-0_17
K. Siddiqi, J. Zhang, D. Macrini, A. Shokoufandeh, S. Bouix, and S. Dickinson. Retrieving articulated 3-D models using medial surfaces. Machine Vis. Appl. 19.4 (2008), pp. 261–275. doi: 10.1007/s00138-007-0097-8
Sketchfab. 2021. url: https://sketchfab.com/
L. Wasserman. Topological data analysis. Ann. Rev. Stat. Appl. 5 (2018), pp. 501–532. doi: 10.1146/annurev-statistics-031017-10004
AMČR - archeologický záznam M-202002857A
No full textStav: 3Označení: 942/20Lokalizace/okolnosti: parc. č. 92, 86Souhrn/upřesnění: Negativní dohled.
(v oznámení uvedené chybné parcelní číslo - souvisí s akcí 940/20 - NN Herzig - pravděpodobně chyba projektanta)
Stručný popis zemních prací: Liniová stavba – zemní práce spojené s výkopy pro uložení nového podzemního kabelového vedení NN, úprava vedení NN. Celková délka řešeného úseku cca 10 m
The evaluation of sports career of the runner Jarmila Kratochvílová from 1980 - 1984
No full textTitle: The evaluation of sports career of the runner Jarmila Kratochvílová from 1980 to 1984 Student: Martin Chyba Supervisor: PhDr. Aleš Kaplan, PhD. Aim: The aim of this bachelor work is the evaluation of sports career of the runner Jarmila Kratochvílová from 1980 to 1984. Methodology: The work was divided into two main parts. In the first one, I evaluated the sports career of Jarmila Kratochvílová from 1980 to 1984. I made the evaluation on the basis of the content analysis of the newspapers articles, published in the monitored period in the daily newspapers Mladá fronta. I adapted statistically the number of the articles in particular year, I categorised these articles according to the methodology of Volf (2007), adapted for the evaluation of sports career of Jarmila Kratochvílová. Then I composed the number of starts in particular seasons and I divided these starts into indoor and outdoor. For every year I chose the best achieved time and I mentioned the placing, which the runner gained in the world chart in the end of the year. In each of these years I mentioned the biggest successes according to the author of this bachelor work. Every season evaluated Jarmila Kratochvílová too. The second part of this work contains the regulated interview realised with Jarmila Kratochvílová. Results: In this..
The Longitudinal study of aging, 1984-90
No full textByy Mary Grace Kovar, Office of Vital and Health Statistics Systems, Joseph E. Fitti and Michele M. Chyba, Division of Health Interview Statistics."Includes descriptions of the samples, interviewing and matching procedures, contents of questionnaires and public-use data files, and a discussion of statistical and analytic issues for the longitudinal study of aging, 1984-90, and the public-use data files released through 1991."Includes bibliographical references (p. 47).199215028171115
AMČR - archeologický záznam M-202300588A
No full textStav: 3Označení: 067/2023Lokalizace/okolnosti: Prostor V od č. p. 128.Souhrn/upřesnění: parc. č. 1173 není dohledatelné v ČUZK. Rozdělení pozemnku, chyba
Experimental demonstration of electric power generation from Earth's rotation through its own magnetic field
No full textEarth rotates through the axisymmetric part of its own magnetic field, but a simple proof shows that it is impossible to use this to generate electricity in a conductor rotating with Earth. However, we previously identified implicit assumptions underlying this proof and showed theoretically that these could be violated and the proof circumvented. This requires using a soft magnetic material with a topology satisfying a particular mathematical condition and a composition and scale favoring magnetic diffusion, i.e., having a low magnetic Reynolds number R_{m} [Chyba and Hand, Phys. Rev. Appl. 6, 014017 (2016)2331-701910.1103/PhysRevApplied.6.014017]. Here we realize these requirements with a cylindrical shell of manganese-zinc ferrite. Controlling for thermoelectric and other potentially confounding effects (including 60 Hz and RF background), we show that this small demonstration system generates a continuous DC voltage and current of the (low) predicted magnitude. We test and verify other predictions of the theory: voltage and current peak when the cylindrical shell's long axis is orthogonal to both Earth's rotational velocity v and magnetic field; voltage and current go to zero when the entire apparatus (cylindrical shell together with current leads and multimeters) is rotated 90^{∘} to orient the shell parallel to v; voltage and current again reach a maximum but of opposite sign when the apparatus is rotated a further 90^{∘}; an otherwise-identical solid MnZn ferrite cylinder generates zero voltage at all orientations; and a high-R_{m} cylindrical shell produces zero voltage. We also reproduce the effect at a second experimental location. The purpose of these experiments was to test the existence of the predicted effect. Ways in which this effect might be scaled to generate higher voltage and current may now be investigated
Optimization problems for controlled mechanical systems : bridging the gap between theory and application
No full textMechanical control systems have become a part of our everyday life. Systems such as automobiles, robot manipulators, mobile robots, satellites, buildings with active vibration controllers and air conditioning systems, make life easier and safer, as well as help us explore the world we live in and exploit it’s available resources. In this chapter, we examine a specific example of a mechanical control system; the Autonomous Underwater Vehicle (AUV). Our contribution to the advancement of AUV research is in the area of guidance and control. We present innovative techniques to design and implement control strategies that consider the optimization of time and/or energy consumption.\ud
Recent advances in robotics, control theory, portable energy sources and automation increase our ability to create more intelligent robots, and allows us to conduct more explorations by use of autonomous vehicles. This facilitates access to higher risk areas, longer time underwater, and more efficient exploration as compared to human occupied vehicles. The use of underwater vehicles is expanding in every area of ocean science. Such vehicles are used by oceanographers, archaeologists, geologists, ocean engineers, and many others. These vehicles are designed to be agile, versatile and robust, and thus, their usage has gone from novelty to necessity for any ocean expedition.\u
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