The Experts below are selected from a list of 73278 Experts worldwide ranked by ideXlab platform
S J Hanchak - One of the best experts on this subject based on the ideXlab platform.
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an empirical equation for Penetration Depth of ogive nose projectiles into concrete targets
International Journal of Impact Engineering, 1994Co-Authors: Michael J Forrestal, B S Altman, J D Cargile, S J HanchakAbstract:Summary We conducted Depth of Penetration experiments with ogive-nose projectiles concrete targets with unconfined compressive strengths of nominally 14 MPa (2 ksi), 35 MPa (5 ksi), and 97 MPa (14 ksi). From our data and the data presented by Canfield and Clator [ J. A. Canfield and I. G. Clator , Development of a scaling law and techniques to investigate Penetration in concrete. NWL Report No. 2057, U.S. Naval Weapons Laboratory, Dahlgren, VA (1966) ] [1], we developed an empirical equation for Penetration Depth of ogive-nose projectiles penetrating concrete targets at normal impact. Our Penetration equation contains a single, dimensionless empirical constant that depends only on the unconfined compressive strength of the target. We determine the empirical constant from Penetration Depth versus striking velocity data with six sets of Penetration data for striking velocities between 250 and 800 m/s. Predictions are in good agreement with all six data sets.
Dinesh Manocha - One of the best experts on this subject based on the ideXlab platform.
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incremental Penetration Depth estimation between convex polytopes using dual space expansion
IEEE Transactions on Visualization and Computer Graphics, 2004Co-Authors: Young J Kim, Ming C Lin, Dinesh ManochaAbstract:We present a fast algorithm to estimate the Penetration Depth between convex polytopes in 3D. The algorithm incrementally seeks a "locally optimal solution" by walking on the surface of the Minkowski sums. The surface of the Minkowski sums is computed implicitly by constructing a local dual mapping on the Gauss map. We also present three heuristic techniques that are used to estimate the initial features used by the walking algorithm. We have implemented the algorithm and compared its performance with earlier approaches. In our experiments, the algorithm is able to estimate the Penetration Depth in about a milli-second on an 1 GHz Pentium PC. Moreover, its performance is almost independent of model complexity in environments with high coherence between successive instances.
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deep dual space expansion for estimating Penetration Depth between convex polytopes
International Conference on Robotics and Automation, 2002Co-Authors: Young J Kim, Ming C Lin, Dinesh ManochaAbstract:We present an incremental algorithm to estimate the Penetration Depth between convex polytopes in 3D. The algorithm incrementally seeks a "locally optimal solution" by walking on the surface of the Minkowski sums. The surface of the Minkowski sums is computed implicitly by constructing a local Gauss map. In practice, the algorithm works well when there is high motion coherence in the environment and is able to compute the optimal solution in most cases.
I Watanabe - One of the best experts on this subject based on the ideXlab platform.
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Penetration Depth into dental casting alloys by nd yag laser
Journal of Biomedical Materials Research Part B, 2005Co-Authors: N Baba, I WatanabeAbstract:This study investigated the effect of laser-beam welding conditions [voltage (V) and spot diameter (mm)] on the Penetration Depth into dental casting alloys. Castings (3.0 mm x 8.0 mm x 50 mm) were prepared from the metals used in this study: commercially pure titanium (CP Ti), Ti-6Al-4V, Ti-6Al-7Nb, cobalt-chromium alloy (Co-Cr) and Type IV gold alloy. Two cast blocks of each metal were butted against one another at the 8.0 x 50-mm surfaces. They were then welded at their interface under the following conditions: voltage of 160-340 V, spot diameter of 0.4-1.6 mm, and pulse duration of 10 ms. After laser welding, the blocks were separated, and the Penetration Depth into each alloy was measured. The data were analyzed with the use of ANOVA at the p < 0.05 level of significance. The Penetration Depths were as follows: CP Ti (0.29-6.45 mm), Ti-6Al-4V (0.32-5.24 mm), Ti-6Al-7Nb (0.34-5.65 mm), Co-Cr (0.24-6.15 mm), and Type IV gold alloy (0.12-5.22 mm). The voltage and spot diameter affected the Penetration Depth into the metals tested. When the voltage increased and the spot diameter decreased, the Penetration Depth increased for each metal. Selecting suitable conditions for laser welding to obtain sufficient Penetration Depth for the optimal thickness of the metal is important when welding prostheses.
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Penetration Depth into dental casting alloys by nd yag laser
Journal of Biomedical Materials Research Part B, 2005Co-Authors: N Baba, I WatanabeAbstract:This study investigated the effect of laser-beam welding conditions [voltage (V) and spot diameter (mm)] on the Penetration Depth into dental casting alloys. Castings (3.0 mm × 8.0 mm × 50 mm) were prepared from the metals used in this study: commercially pure titanium (CP Ti), Ti-6Al-4V, Ti-6Al-7Nb, cobalt–chromium alloy (Co–Cr) and Type IV gold alloy. Two cast blocks of each metal were butted against one another at the 8.0 × 50-mm surfaces. They were then welded at their interface under the following conditions: voltage of 160–340 V, spot diameter of 0.4–1.6 mm, and pulse duration of 10 ms. After laser welding, the blocks were separated, and the Penetration Depth into each alloy was measured. The data were analyzed with the use of ANOVA at the p < 0.05 level of significance. The Penetration Depths were as follows: CP Ti (0.29–6.45 mm), Ti-6Al-4V (0.32–5.24 mm), Ti-6Al-7Nb (0.34–5.65 mm), Co–Cr (0.24–6.15 mm), and Type IV gold alloy (0.12–5.22 mm). The voltage and spot diameter affected the Penetration Depth into the metals tested. When the voltage increased and the spot diameter decreased, the Penetration Depth increased for each metal. Selecting suitable conditions for laser welding to obtain sufficient Penetration Depth for the optimal thickness of the metal is important when welding prostheses. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 72B: 64–68, 2005
Spiros Zinelis - One of the best experts on this subject based on the ideXlab platform.
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effect of nd yag laser parameters on the Penetration Depth of a representative ni cr dental casting alloy
Lasers in Medical Science, 2015Co-Authors: Youssef Al S Jabbari, Theodoros Koutsoukis, Xanthoula Barmpagadaki, Ehab A Eldanaf, R A Fournelle, Spiros ZinelisAbstract:The effects of voltage and laser beam (spot) diameter on the Penetration Depth during laser beam welding in a representative nickel–chromium (Ni–Cr) dental alloy were the subject of this study. The cast alloy specimens were butted against each other and laser welded at their interface using various voltages (160–390 V) and spot diameters (0.2–1.8 mm) and a constant pulse duration of 10 ms. After welding, the laser beam Penetration Depths in the alloy were measured. The results were plotted and were statistically analyzed with a two-way ANOVA, employing voltage and spot diameter as the discriminating variables and using Holm–Sidak post hoc method (a = 0.05). The maximum Penetration Depth was 4.7 mm. The Penetration Depth increased as the spot diameter decreased at a fixed voltage and increased as the voltage increased at a fixed spot diameter. Varying the parameters of voltage and laser spot diameter significantly affected the Depth of Penetration of the dental cast Ni–Cr alloy. The Penetration Depth of laser-welded Ni–Cr dental alloys can be accurately adjusted based on the aforementioned results, leading to successfully joined/repaired dental restorations, saving manufacturing time, reducing final cost, and enhancing the longevity of dental prostheses.
Young J Kim - One of the best experts on this subject based on the ideXlab platform.
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incremental Penetration Depth estimation between convex polytopes using dual space expansion
IEEE Transactions on Visualization and Computer Graphics, 2004Co-Authors: Young J Kim, Ming C Lin, Dinesh ManochaAbstract:We present a fast algorithm to estimate the Penetration Depth between convex polytopes in 3D. The algorithm incrementally seeks a "locally optimal solution" by walking on the surface of the Minkowski sums. The surface of the Minkowski sums is computed implicitly by constructing a local dual mapping on the Gauss map. We also present three heuristic techniques that are used to estimate the initial features used by the walking algorithm. We have implemented the algorithm and compared its performance with earlier approaches. In our experiments, the algorithm is able to estimate the Penetration Depth in about a milli-second on an 1 GHz Pentium PC. Moreover, its performance is almost independent of model complexity in environments with high coherence between successive instances.
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deep dual space expansion for estimating Penetration Depth between convex polytopes
International Conference on Robotics and Automation, 2002Co-Authors: Young J Kim, Ming C Lin, Dinesh ManochaAbstract:We present an incremental algorithm to estimate the Penetration Depth between convex polytopes in 3D. The algorithm incrementally seeks a "locally optimal solution" by walking on the surface of the Minkowski sums. The surface of the Minkowski sums is computed implicitly by constructing a local Gauss map. In practice, the algorithm works well when there is high motion coherence in the environment and is able to compute the optimal solution in most cases.
