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Journal articles on the topic 'Ellipsoidal reflector'

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Author: Grafiati

Published: 30 May 2022

Last updated: 31 May 2022

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1

Bezuglyi, M. A., N. V. Bezuglaya, A. V. Ventsuryk, and K. P. Vonsevych. "Angular Photometry of Biological Tissue by Ellipsoidal Reflector Method." Devices and Methods of Measurements 10, no. 2 (June 24, 2019): 160–68. http://dx.doi.org/10.21122/2220-9506-2019-10-2-160-168.

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Angular measurements in optics of biological tissues are used for different applied spectroscopic task for roughness surface control, define of refractive index and for research of optical properties. Purpose of the research is investigation of the reflectance of biologic tissues by the ellipsoidal reflector method under the variable angle of the incident radiation.The research investigates functional features of improved photometry method by ellipsoidal reflectors. The photometric setup with mirror ellipsoid of revolution in reflected light was developed. Theoretical foundations of the design of an ellipsoidal reflector with a specific slot to ensure the input of laser radiation into the object area were presented. Analytical solution for calculating the angles range of incident radiation depending on the eccentricity and focal parameter of the ellipsoid are obtained. Also created the scheme of image processing at angular photometry by ellipsoidal reflector.The research represents results of experimental series for samples of muscle tissues at wavelengths 405 nm, 532 nm, 650 nm. During experiment there were received photometric images on the equipment with such parameters: laser beam incident angles range 12.5–62.5°, ellipsoidal reflector eccentricity 0.6, focal parameter 18 mm, slot width 8 mm.The nature of light scattering by muscle tissues at different wavelengths was represented by graphs for the collimated reflection area. The investigated method allows qualitative estimation of influence of internal or surface layers of biologic tissues optical properties on the light scattering under variable angles of incident radiation by the shape of zone of incident light.

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2

Bezuglaya, N. V., A. A. Haponiuk, D. V. Bondariev, S. A. Poluectov, V. A. Chornyi, and M. A. Bezuglyi. "Rationale for the Choice of the Ellipsoidal Reflector Parameters for Biomedical Photometers." Devices and Methods of Measurements 12, no. 4 (December 22, 2021): 259–71. http://dx.doi.org/10.21122/2220-9506-2021-12-4-259-271.

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Biomedical photometersʼ information-measuring systems with ellipsoidal reflectors have acceptable results in determining of biological tissues optical properties in the visible and near-infrared spectral range. These photometers make it possible to study the optical radiation propagation in turbid media for direct and inverse problems of light-scattering optics. The purpose of this work is to study the influence of the ellipsoidal reflectors design parameters on the results of biomedical photometry when simulating the optical radiation propagation in a system of biological tissue and reflectors in transmitted and reflected light.The paper substantiates the choice of the ellipsoidal reflectors’ focal parameter for efficient registration of forward and backscattered light. The methodology of the process is illustrated by the results of a model experiment using the Monte Carlo simulation for samples of human brain white and gray matter at the visible range of 405 nm, 532 nm, and 650 nm. The total transmittance, diffuse reflectance, and absorption graphs depending on the sample thickness were obtained. Based on the introduced concepts of the ellipsoidal reflector efficiency index and its efficiency factor, the expediency of choosing the ellipsoidal reflectors focal parameter is analyzed to ensure the registration of the maximum amount of scattered light. The graphs of efficiency index in reflected and transmitted light for different thickness samples of white and gray matter and efficiency factors depending on the sample thickness were obtained.The influence of the reflectors ellipticity on the illuminance of various zones of photometric images using the example of an absorbing biological medium – pig liver tissue – at wavelength of 405 nm with a Monte Carlo simulation was analyzed.The optical properties of biological media (scattering and absorption coefficients, scattering anisotropy factor, refractive index) and the samples’ geometric dimensions, particularly the thickness, are predetermined when choosing the ellipsoidal reflectors parameters for registration of the scattered light. Coordinates of the output of photons and their statistical weight obtained in the Monte Carlo simulation of light propagation in biological tissue have a physical effect on a characteristic scattering spot formation in the receiving plane of a biomedical photometer with ellipsoidal reflectors.

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3

He, Jun Feng, and Chang Chun Huang. "Large Amount of Off-Axis Machining Ellipsoidal Reflector." Applied Mechanics and Materials 484-485 (January 2014): 254–58. http://dx.doi.org/10.4028/www.scientific.net/amm.484-485.254.

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The article introduces the off-axis ellipsoidal mirror processing and testing, and uses AutoCAD software to calculate the maximum aspheric mirrors degrees. After processing the off-axis ellipsoidal reflector inclination error of 1.55arcsec, root mean square roughness ((RMS) of 3.21nn, focal length error is less than 1mm, and the surface accuracy can reach λ / 6 (0.51-0.98 μ m).

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4

He Junfeng, 贺军峰, 田润澜 Tian Runlan, 田桢熔 Tian Zhenrong, and 白东峰 Bai Dongfeng. "Fabrication of Large Amount Off-xis Ellipsoidal Reflector." Laser & Optoelectronics Progress 45, no. 12 (2008): 64–67. http://dx.doi.org/10.3788/lop20084512.0064.

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5

Bezuglyi, Mikhail, Ivan Sinyavski, Natalia Bezuglaya, and Andrii Kozlovskyi. "MANUFACTURING SPECIAL FEATURES OF ELLIPSOIDAL REFLECTOR FOR PHOTOMETERS." Bulletin of Kyiv Polytechnic Institute. Series Instrument Making, no. 52(2) (December 30, 2016): 76–81. http://dx.doi.org/10.20535/1970.52(2).2016.92959.

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6

Ying, Shang-Ping, Bing-Mau Chen, Han-Kuei Fu, and Chen-Yu Yeh. "Single Headlamp with Low- and High-Beam Light." Photonics 8, no. 2 (January 27, 2021): 32. http://dx.doi.org/10.3390/photonics8020032.

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Generally, automobiles are typically equipped with separate headlamp lanterns for generating low- and high-beam light. Compared with separate headlamp lanterns, a single headlamp producing both low- and high-beam light can be more compact and have less mechanical complexity. The single headlamp structure has become a main emphasis of research that manufacturers will continue to focus great efforts on in the future. A novel design of a single headlamp generating both low- and high-beam light is proposed in this study. The proposed headlamp consists of a compound ellipsoidal reflector, a baffle plate, a condenser lens, and LED array devices generating low- and high-beam light. The compound ellipsoidal reflector comprises a primary ellipsoidal reflector for generating low-beam light and a secondary ellipsoidal reflector for generating high-beam light. Monte Carlo ray tracing simulations were performed to confirm the optical characteristics of the proposed design. A prototype of the proposed headlamp was also fabricated and assembled to verify the design’s effectiveness. The simulated and measured illuminance distributions of the low-beam and high-beam light had the desired light patterns. Moreover, all the simulated and measured illuminances of each point and line met the ECE R112 regulation for low-beam and high-beam light. The proposed headlamp in this study is feasible for the application of single headlamp generating both low- and high-beam light.

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7

Yao, Manwen, and John C. Wolfe. "A laser-induced fluorescence biosensor by using ellipsoidal reflector." Optics & Laser Technology 39, no. 5 (July 2007): 1040–45. http://dx.doi.org/10.1016/j.optlastec.2006.05.002.

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8

Kang, Yang, Ning Li, Chun-Sheng Weng, and Chuan-Wei Wang. "Acoustic characteristics of pulse detonation engine with ellipsoidal reflector." Chinese Physics B 27, no. 10 (October 2018): 104703. http://dx.doi.org/10.1088/1674-1056/27/10/104703.

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9

Yazgan, E. "The radiation pattern of a surface loaded ellipsoidal reflector." IEEE Transactions on Antennas and Propagation 35, no. 3 (March 1987): 347–49. http://dx.doi.org/10.1109/tap.1987.1144102.

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10

Bailey, Michael R. "Acoustic and cavitation fields of a pressure release ellipsoidal reflector." Journal of the Acoustical Society of America 101, no. 5 (May 1997): 3138. http://dx.doi.org/10.1121/1.418972.

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11

Dai, Xiaowei, Yi-Te Tsai, Michael R. Haberman, and Jinying Zhu. "Characterization of a spark source focused by an ellipsoidal reflector." Journal of the Acoustical Society of America 134, no. 5 (November 2013): 4196. http://dx.doi.org/10.1121/1.4831393.

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12

Young, J. F., J. J. Macklin, and S. E. Harris. "Grazing-incidence ellipsoidal reflector for longitudinally pumping short-wavelength lasers." Optics Letters 12, no. 2 (February 1, 1987): 90. http://dx.doi.org/10.1364/ol.12.000090.

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13

Wright, Wayne M., and David T. Blackstock. "Focusing of N waves in air by an ellipsoidal reflector." Journal of the Acoustical Society of America 102, no. 2 (August 1997): 741–46. http://dx.doi.org/10.1121/1.419950.

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14

Garcia-Pino, Antonio, Nuria Llombart, Borja Gonzalez-Valdes, and Oscar Rubinos-Lopez. "A Bifocal Ellipsoidal Gregorian Reflector System for THz Imaging Applications." IEEE Transactions on Antennas and Propagation 60, no. 9 (September 2012): 4119–29. http://dx.doi.org/10.1109/tap.2012.2207064.

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15

SHIMAOKA, Keiichi, Isao AOYAGI, Kanae HAMAGUCHI, Hiroko IGUCHI, Takashi OZAKI, Norio FUJITSUKA, Yutaka NONOMURA, and Teruhisa AKASHI. "Two-Dimensional Laser Scanning Utilizing Inclined Rolling of an Ellipsoidal Reflector." Journal of the Japan Society for Precision Engineering 85, no. 11 (November 5, 2019): 1005–12. http://dx.doi.org/10.2493/jjspe.85.1005.

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16

Samuels, Joshua, and Vesna Zderic. "Ellipsoidal‐reflector high intensity focused ultrasound system with integrated safety monitoring." Journal of the Acoustical Society of America 125, no. 4 (April 2009): 2622. http://dx.doi.org/10.1121/1.4783995.

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17

Bezuglyi, Mikhail O., Natalia V. Bezuglaya, and Andrii V. Nahornyi. "Control of Optical Clearing of Human Skin by Ellipsoidal Reflector Method." Microsystems, Electronics and Acoustics 24, no. 2 (April 30, 2019): 6–13. http://dx.doi.org/10.20535/2523-4455.2019.24.2.172771.

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18

Xu, Yingshun, Nannan Liu, Xuehui Bao, Bin Liu, and Hui Shen. "A Quarter Ellipsoidal Reflector Enhancing Fluorescence Collection Efficiency For Multiphoton Microscopes." IEEE Photonics Journal 8, no. 5 (October 2016): 1–9. http://dx.doi.org/10.1109/jphot.2016.2615284.

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19

Llombart, Nuria, Ken B. Cooper, Robert J. Dengler, Tomas Bryllert, and Peter H. Siegel. "Confocal Ellipsoidal Reflector System for a Mechanically Scanned Active Terahertz Imager." IEEE Transactions on Antennas and Propagation 58, no. 6 (June 2010): 1834–41. http://dx.doi.org/10.1109/tap.2010.2046860.

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20

Vonsevych, Kostiantyn P., Mikhail O. Bezuglyi, and Olha A. Prytula. "OPTICAL FEEDBACK BASED ON THE PHOTOMETRYBY ELLIPSOIDAL REFLECTOR IN BIONIC FINGERS APPLICATION." KPI Science News, no. 3 (August 13, 2019): 63–72. http://dx.doi.org/10.20535/kpi-sn.2019.3.175785.

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21

Chou, H. T., L. R. Kuo, H. H. Chou, K. L. Hung, and P. Nepa. "Realistic implementation of ellipsoidal reflector antennas to produce near-field focused patterns." Radio Science 46, no. 5 (September 20, 2011): n/a. http://dx.doi.org/10.1029/2010rs004541.

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22

Cheng, Stephen T. W., Matthew R. Jones, David T. Blackstock, and Wayne M. Wright. "Focusing of an N wave by an ellipsoidal reflector: An experiment in air." Journal of the Acoustical Society of America 85, S1 (May 1989): S113. http://dx.doi.org/10.1121/1.2026651.

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23

Ren Lanxu, 任兰旭, 魏秀东 Wei Xiudong, 牛文达 Niu Wenda, 王鹤 Wang He, 许文斌 Xu Wenbin, 肖君 Xiao Jun, and 卢振武 Lu Zhenwu. "A High Flux Solar Simulator Based on an Array of Non-Coaxial Ellipsoidal Reflector." Acta Optica Sinica 32, no. 10 (2012): 1022002. http://dx.doi.org/10.3788/aos201232.1022002.

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24

Chu, Shu-Chun, Po-Yo Chen, Cing-Yi Huang, and Kuo-Chih Chang. "Design of a high-efficiency LED low-beam headlamp using Oliker’s compound ellipsoidal reflector." Applied Optics 59, no. 16 (May 27, 2020): 4872. http://dx.doi.org/10.1364/ao.385680.

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25

Tuan, Shih-Chung, Hsi-Tseng Chou, Kung-Yu Lu, and Hsi-Hsir Chou. "Analytic Transient Analysis of Radiation From Ellipsoidal Reflector Antennas for Impulse-Radiating Antennas Applications." IEEE Transactions on Antennas and Propagation 60, no. 1 (January 2012): 328–39. http://dx.doi.org/10.1109/tap.2011.2167919.

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26

Gao Jing, 高静, 卢启鹏 Lu Qipeng, 彭忠琦 Peng Zhongqi, and 丁海泉 Ding Haiquan. "Parameter Design and Optimization of Collecting Light Ellipsoidal Reflector in Near Infrared Noninvasive Biochemical Analysis." Acta Optica Sinica 32, no. 8 (2012): 0822007. http://dx.doi.org/10.3788/aos201232.0822007.

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27

Chou, Hsi-Tseng, Hsiang-Ting Cheng, Sheng-Ju Chou, Li-Ruei Kuo, Alice Buffi, and Paolo Nepa. "Dome-Shaped Ellipsoidal Reflector Antenna for UHF-RFID Readers With Confined Near-Field Detection Region." IEEE Antennas and Wireless Propagation Letters 16 (2017): 2505–8. http://dx.doi.org/10.1109/lawp.2017.2727077.

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28

Chou, Hsi-Tseng. "Near-Field Finite-Zone Focused Radiation From Reflector Antenna With Continuously Tapered Ellipsoidal Surface Curvatures." IEEE Transactions on Antennas and Propagation 67, no. 10 (October 2019): 6344–52. http://dx.doi.org/10.1109/tap.2019.2922785.

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29

Averkiou, Michalakis A., Robin O. Cleveland, and Ronald A. Roy. "The small‐amplitude, continuous wave reflected field produced by a spherical source placed at the focus of an ellipsoidal reflector." Journal of the Acoustical Society of America 100, no. 4 (October 1996): 2748. http://dx.doi.org/10.1121/1.416881.

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30

Chou, H. ‐T, and S. ‐C Tuan. "Analytic transient analysis of radiation from hyperboloid reflector antennas via surface curvature continuation of ellipsoidal surfaces." Electronics Letters 49, no. 6 (March 2013): 381–82. http://dx.doi.org/10.1049/el.2012.4409.

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31

Xing, Xiaoxue, Yanmin Lei, Weiwei Shang, Limin Du, and Pan Guo. "Theoretical Research on Ellipsoidal Structure Methane Gas Detection Based on Near Infrared Light Sources of PbSe Quantum Dots." Journal of Nanomaterials 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/6548380.

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To improve the precision and sensitivity of the detection in near infrared gas detection system, the selection of light source and design of gas chamber structure are two key links. In this paper, the near infrared (NIR) light sources fabricated with PbSe quantum dots (QDs) and a new gas cell structure using an ellipsoid reflector were designed to test the concentration of methane (CH4). The double wavelengths differential detection method was used in the paper. The signal wavelength is 1.665 μm from the NIR QD-based light source with 5.1 nm PbSe QDs. The reference wavelength is 1.943 μm from the NIR QD-based light source with 6.1 nm PbSe QDs. The experimental results show that the differential gain signal could be enhanced 80 times when the major axis, the focus, and the open length of the ellipsoid reflector are 4.18 cm, 3.98 cm, and 0.36 cm, respectively. The structure will be convenient for the signal amplifying, AD converting, and other process in the latter circuits, and therefore both the detection sensitivity and precision can be improved.

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32

Chen, Tianyang, Xiaodong Chen, Yuan Yao, Xiaoming Liu, and Junsheng Yu. "A Gaussian Beam Mode Analysis Method for 3-D Multi-Reflector Quasi-Optical Systems." Electronics 10, no. 4 (February 20, 2021): 499. http://dx.doi.org/10.3390/electronics10040499.

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3-D quasi-optical systems have a more comprehensive range of application scenarios, and their analysis and design are more complicated than those of 2-D systems. In this work, we improve Gaussian beam mode analysis (GBMA) to analyze 3-D multi-reflector systems. The expressions of co- and cross-polarization and their derivations are given and discussed in detail. Furthermore, several 3-D dual-reflector systems with different rotation angles are chosen as simulation examples to assess the validity and precision of 3-D GBMA compared with physical optics (PO) in the commercial software GRASP10. Furthermore, a 3-D double ellipsoidal reflector system with a π/2 rotation angle operating at 183 GHz is designed, manufactured, and tested. Measured results of the system demonstrate that it is in good agreement with the simulated results of 3-D GBMA and PO for both the co- and cross-polarization. By comparing the computing time performance of 3-D GBMA and PO in GRASP10, the high efficiency of 3-D GBMA is clarified. With 3-D GBMA, the field in 3-D quasi-optical systems can be calculated preciously and rapidly.

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33

Liu, Lei, Rui Guo, Liang Chen, Yu Cao, Yongliang Yang, and Bobo Zhao. "A prediction model for two-dimensional pressure distribution from underwater shock wave focusing by an ellipsoidal reflector." Journal of the Acoustical Society of America 140, no. 6 (December 2016): 4506–16. http://dx.doi.org/10.1121/1.4971327.

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34

Zhang, Zhen Fu, Xin Wu Zeng, Qing Yu Cai, and Kai Feng Han. "Numerical Simulation on Underwater Shock Wave Focusing." Applied Mechanics and Materials 105-107 (September 2011): 121–26. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.121.

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Shock wave focusing by an ellipsoidal reflector can produce higher pressure in the focal region. The focusing process of shock wave was studied by theory analyses and numerical results. Base on the experimental observation the shock wave source is equivalent to the explosion of an underwater explosive. A finite element model was set up to investigate the shock wave focusing behaviors. Both the pressure-time history and the peak pressure along the axial position were presented. The shock wave focusing process was shown. The interactions of waves in the focal region are shown. A modified EOS of water was applied, which can be used to analyze the negative pressure observed; the numerical results based on the modified EOS agree well with the experimental data.

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35

Dai, Xiaowei, Michael R. Haberman, Yi-Te Tsai, and Jinying Zhu. "Excitation of Rayleigh and zero-group-velocity Lamb waves using air-borne N-waves focused by an ellipsoidal reflector." Journal of the Acoustical Society of America 133, no. 5 (May 2013): 3498. http://dx.doi.org/10.1121/1.4806211.

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36

LIANG, SHEN-MIN, KIET-HOUNG CHOW, IOANNIS MANOUSAKAS, YONG-REN PU, and CHIEN-CHEN CHANG. "DESIGN AND FABRICATION OF A SHOCK WAVE GENERATOR FOR MUSCULOSKELETAL DISORDERS." Biomedical Engineering: Applications, Basis and Communications 18, no. 01 (February 25, 2006): 24–29. http://dx.doi.org/10.4015/s1016237206000063.

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In the past ten years, extracorporeal shock waves have been successfully used in orthopedics. The idea of shock wave therapy is the stimulation of a healing process. Electrohydraulic shock wave therapy provides higher energy density flux than electromagnetic and piezoelectric types. But electrohydraulic shock wave generators are less stable than the other two types because of electrode erosion. In this study, a shock wave generator with a controllable spark gap system has been designed in order to give steady output pressures by automatic adjustment of the electrode gap. An ellipsoidal shock wave reflector is equipped with two AC servo motors with drivers. The motor driver actuates the associated motor which is connected to an electrode base by a belt. On a designed image feedback system, a CCD camera is used as the image detection tool to measure the electrode gap. Experimental results show the coincidence of the second focus of the shock wave reflector with the gas-dynamic focus. Moreover, measurements of focused pressure and energy intensity with PCB and PVDF pressure sensors and tests of stone fragmentation efficiency have been carried out to evaluate the performance of the newly designed shock wave generator with a gap-adjusted system and an image feedback system. It is found that the designed electrohydraulic shock wave generator is stable and efficient in pressure output with a low cost of electrodes.

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37

CHRISTOPHER, TED. "A NONPLANAR SOURCE TO PLANAR APERTURE ALGORITHM." Journal of Computational Acoustics 02, no. 04 (December 1994): 453–69. http://dx.doi.org/10.1142/s0218396x94000269.

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A new algorithm for modeling the propagation within a nonplanar source is presented. The algorithm represents the effects of diffraction and attenuation in the propagation of acoustic waves from a nonplanar source to the associated source aperture. The algorithm is a generalization of the linear propagation methods of Christopher and Parker [J. Acous. Soc. Am.90, 507–521 (1991)]. When used to propagate the normal velocity source description to obtain a pressure description of the field, the algorithm is equivalent to the Rayleigh integral model of Williams [J. Acous. Soc, Am.17, 219–227 (1946)] and O'Neil [J. Acous. Soc. Am.21, 516–526 (1949)]. Additionally, in propagating the field beyond the aperture plane the new algorithm allows for specified aperture plane conditions and facilitates the use of very efficient linear and nonlinear beam propagation methods. The algorithm can also be extended to approximate the effects of reflections occurring within the nonplanar source. An efficient implementation of the algorithm is presented for axially symmetric sources. The correctness of the algorithm and implementation are demonstrated using a hemispherical reflective source. The results of the algorithm are then compared against the predictions of Coulouvrat [J. Acous. Soc. Am.94, 1663–1675 (1993)] and predictions obtained with the analytical axial solution for an ellipsoidal reflector of Hamilton [J. Acous. Soc. Am.93, 1256–1266 (1993)].

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38

Bezuglyi, M. A., N. V. Bezuglaya, and S. Kostuk. "INFLUENCE OF LASER BEAM PROFILE ON LIGHT SCATTERING BY HUMAN SKIN DURING PHOTOMETRY BY ELLIPSOIDAL REFLECTORS." Devices and Methods of Measurements 9, no. 1 (March 20, 2018): 56–65. http://dx.doi.org/10.21122/2220-9506-2018-9-1-56-65.

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The correct accounting of laser emitter parameters for improvement of diagnostic authenticity of methods of optical biomedical diagnostic is important problem for applied biophotonic tasks. The purpose of the current research is estimation of influence of energy distribution profile in transversal section of laser beam on light scattering by human skin layers at photometry by ellipsoidal reflectors.Biomedical photometer with ellipsoidal reflectors for investigation of biological tissue specimens in transmitted and reflected light uses laser probing radiation with infinitely thin, Gauss-type and uniform cross-section profile. Distribution of beams with denoted profiles, which consist of 20 million photons with wavelength 632.8 nm, was modeled by using of Monte-Carlo simulation in human skin layers (corneous layer, epidermis, derma and adipose tissue) of various anatomic thickness and with ellipsoidal reflectors with focal parameter equal to 16.875 mm and eccentricity of 0.66.The modeling results represent that illuminance distribution in zones of photometric imaging is significantly influenced by the laser beam cross-section profile for various thickness of corneous layer and epidermis in transmitted and reflected light, and also derma in reflected light. Illuminance distribution for adipose tissue in reflected and transmitted light, and also derma in transmitted light, practically do not depend of laser beam profile for anatomic thicknesses, which are appropriate for human skin on various sections of body.There are represented results of modified Monte-Carlo simulation method for biomedical photometer with ellipsoidal reflectors during biometry of human skin layers. For highly scattered corneous layer and epidermis the illumination of middle and external rings of photometric images changes depending from the laser beam profile for more than 50 % in transmitted and 30 % in reflected light. For weakly scattering skin layers (derma and adipose layer) the influence of profile can be observed only for derma in reflected layer and is equal not more than 15 %.

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39

Gomel, Roy, Simchon Faigler, Tsevi Mazeh, and Michał Pawlak. "Search for dormant black holes in ellipsoidal variables – III. The OGLE BULGE short-period sample." Monthly Notices of the Royal Astronomical Society 504, no. 4 (May 3, 2021): 5907–18. http://dx.doi.org/10.1093/mnras/stab1235.

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ABSTRACT This is the third of a series of papers that presents an algorithm to search for close binaries with massive, possibly compact, unseen secondaries. The detection of such a binary is based on identifying a star that displays a large ellipsoidal periodic modulation, induced by tidal interaction with its companion. In the second paper of the series, we presented a simple approach to derive a robust modified minimum mass ratio (mMMR), based on the observed ellipsoidal amplitude, without knowing the primary mass and radius, assuming the primary fills its Roche lobe. The newly defined mMMR is always smaller than the actual mass ratio. Therefore, a binary with an mMMR larger than unity is a good candidate for having a massive secondary, which might be a black hole or a neutron star. This paper considers 10 956 OGLE short-period ellipsoidals observed towards the Galactic bulge. We re-analyse their modulation and identify 136 main-sequence systems with mMMR significantly larger than unity as candidates for having compact-object secondaries, assuming their observed periodic modulations reflect indeed the ellipsoidal effect. Obviously, one needs follow-up observations to find out the true nature of these companions.

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40

Bezugla, Natalia, Serhii Poluectov, Vladyslav Chornyi, and Mikhail Bezuglyi. "MONTE CARLO SIMULATION OF LIGHT SCATTERING IN HUMAN SKIN LAYERS BY SPATIAL PHOTOMETRY METHODS." Bulletin of Kyiv Polytechnic Institute. Series Instrument Making, no. 61(1) (June 30, 2021): 91–100. http://dx.doi.org/10.20535/1970.61(1).2021.237112.

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The ability to register and analyze the spatial distribution of light scattered within the full solid angle is the basis for the development and improvement of information-measuring systems and software and hardware complexes for problems of optical biomedical diagnostics. The greatest contribution to light scattering at non-invasive methods of biomedical research are made by the layers of human skin, affecting the depth of probing and the resolution of diagnostic systems. The significant individual variability of the optical properties of biological tissues does not allow practically (clinically) assessing their effect on the light scattering characteristics; therefore, the use of methods for modeling the optical radiation propagation in media in the measuring tools functioning context makes it possible to provide such a prognostic analysis. The goal of this work is a comparative evaluation of the results of the light propagation in human skin layers by Monte Carlo simulation using information-measuring systems of a biomedical photometer with ellipsoidal reflectors and a goniophotometer. The Monte Carlo simulation results of light scattering in dermis and epidermis at a wavelength of 632.8 nm using spatial photometry methods and the "BT_Mod" software, as well as coordinates, direction, and statistical weight of photons, allows the ray-tracing in a biomedical photometer with ellipsoidal reflectors are presented in this work. As a result of modeling, graphs of the dependence of optical coefficients (transmission T, diffuse reflection Rd, and absorption A) for the studied tissues of various thicknesses on the value of the scattering anisotropy factor were obtained, as well as photometric images of the second focal plane of ellipsoidal reflectors when receiving a scattering spot in reflected and transmitted light. Diagrams of the averaged scattering indicatrix at three thicknesses of the epidermis and dermis were obtained for a set of biophysically significant values of the scattering anisotropy factor, based on which the integral distribution of the photons statistical weight in diffuse scattered light was analyzed. A quantitative assessment of the illuminance level of images is carried out according to the zone analysis principles in photometry by ellipsoidal reflectors. The resulting graphs of the illuminance dependence the external and middle rings of photometric images in reflected and transmitted light. The results of the research make it possible to analyze the spatial distribution of light scattered by the human skin layers (epidermis and dermis) within the full solid angle, which can be used in problems of optical dosimetry and medical imaging in diagnostic, endoscopic, and therapeutic methods of biophotonics.

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Bezuglyi, Mikhail, and Natalia Bezuglaya. "Raman Spectroscopy Principles for in vivo Diagnostic by Ellipsoidal Reflectors." Electrical, Control and Communication Engineering 15, no. 1 (September 1, 2019): 39–46. http://dx.doi.org/10.2478/ecce-2019-0006.

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AbstractThe paper presents the analysis of the functional abilities of measurement tools with ellipsoidal reflectors for Raman spectroscopy. The investigated structural scheme of the setup is intended for use in Raman spectroscopy in vivo by ellipsoidal reflectors. The setup can be used as a prototype for development of a device for non-invasive control of sugar level. Additionally, the investigation demonstrates the efficiency of ellipsoidal photometry method for registration of Raman scattering signal on test-solutions. The testing was performed for different sugar concentrations with the laser radiation wavelength 980 nm. In addition, the selecting principles of laser radiation source parameters (including beam diameter and power) were investigated. During the research, the data about spatial distribution of the backscattered light in human shoulder and finger tissues during photometry by ellipsoidal reflectors were received. The procedure involves application of Monte Carlo simulation. The dependency of the external and middle ring illuminance of photometric images on the diameter and power of the laser beam is represented based on the zone analysis.

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Molland, A. F., and I. K. A. P. Utama. "Experimental and numerical investigations into the drag characteristics of a pair of ellipsoids in close proximity." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 216, no. 2 (December 1, 2002): 107–15. http://dx.doi.org/10.1243/147509002762224324.

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Investigations into the drag of ellipsoids in proximity have been carried out experimentally using a low-speed wind tunnel and numerically using a commercial computational fluid dynamics (CFD) code (CFXTM). The purpose of the investigations was to improve the understanding of the viscous resistance and viscous interaction effects between twin bodies in proximity, such as the hulls of a catamaran, and consequently to improve the techniques for estimating the resistance and powering of commercial catamarans. The wind tunnel tests were carried out on a single ellipsoid with a length-diameter ratio ( L/D) of 6.0 and a pair of similar ellipsoids in proximity at separation-length ratios ( S/L) of 0.27, 0.37, 0.47 and 0.57 at Reynolds number values up to 3.2 ×106. The ellipsoids thus represented a reflex (or reflected) model of a catamaran hull. In the numerical work, investigations were carried out on ellipsoids with the same geometry as those tested in the wind tunnel and ellipsoids with a larger length-diameter ratio. Results of the wind tunnel tests and numerical investigations are presented and compared. It is found from the investigations that viscous form effects and viscous interactions are present for such bodies and that CFD techniques can make very useful contributions to the investigations of these effects.

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Pressprich, Mark, and Joseph Ferrara. "RigakuIntegrate : A New Single Crystal Integration Program." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1439. http://dx.doi.org/10.1107/s205327331408560x.

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RigakuIntegrate is a new single crystal integration program designed to increase integration accuracy by optimizing the reflection domain to exclude all but relevant elastic scattering. Instead of integrating over a shoebox domain, RigakuIntegrate sums over a tailored detector region that incorporates the known diffraction physics of each reflection as it passes through the Ewald sphere, combined with the known properties of the area detector. The reciprocal space reflections are modelled by ellipsoids that account for the crystal radius, beam crossfire, mosaicity, and wavelength dispersion. In case of laboratory sources separate ellipsoids are assigned to each of the Kα1 and Kα2 components. The passage of the reflection through the diffraction condition is modeled by the intersection of the ellipsoid(s) with the Ewald sphere, resulting in a set of ellipses. This set of intersection ellipses is then projected onto the detector plane along the scattered ray direction. Interaction with the detector sensor is modeled by appropriate convolution, resulting in reflection-specific integration domains over the surface of the detector. Results from crystals ranging in quality from exquisite (a charge density analysis of oxalic acid at 100K using a RAPID IP detector) to marginal (a highly mosaic and split crystal that refines to R1(all data) = 2.6% using a Pilatus detector) will be presented.

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Bezuglyi, Mikhail, Olga Linyucheva, Natalia Bezuglaya, Mikhail Byk, and Stepan Kostiuk. "CONTROL OF THE ELLIPSOIDAL REFLECTORS SHAPE FOR BIOMEDICAL PHOTOMETERS." Bulletin of Kyiv Polytechnic Institute. Series Instrument Making, no. 53(1) (June 30, 2017): 62–69. http://dx.doi.org/10.20535/1970.53(1).2017.106543.

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Bezuglyi, M. A., N. V. Bezuglaya, and I. V. Helich. "Ray tracing in ellipsoidal reflectors for optical biometry of media." Applied Optics 56, no. 30 (October 20, 2017): 8520. http://dx.doi.org/10.1364/ao.56.008520.

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Bailey, Michael R., and David T. Blackstock. "Intensified cavitation produced with pressure release and rigid ellipsoidal reflectors." Journal of the Acoustical Society of America 99, no. 4 (April 1996): 2560–74. http://dx.doi.org/10.1121/1.415015.

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Wegg, Christopher, Ortwin Gerhard, and Marie Bieth. "The gravitational force field of the Galaxy measured from the kinematics of RR Lyrae in Gaia." Monthly Notices of the Royal Astronomical Society 485, no. 3 (February 26, 2019): 3296–316. http://dx.doi.org/10.1093/mnras/stz572.

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Abstract From a sample of 15651 RR Lyrae with accurate proper motions in Gaia DR2, we measure the azimuthally averaged kinematics of the inner stellar halo between 1.5 and 20 kpc from the Galactic centre. We find that their kinematics are strongly radially anisotropic, and their velocity ellipsoid nearly spherically aligned over this volume. Only in the inner regions ${\lesssim } 5\, {\rm kpc}\,$ does the anisotropy significantly fall (but still with β > 0.25) and the velocity ellipsoid tilt towards cylindrical alignment. In the inner regions, our sample of halo stars rotates at up to $50\, {\rm km}\, {\rm s}^{-1}\,$, which may reflect the early history of the Milky Way, although there is also a significant angular momentum exchange with the Galactic bar at these radii. We subsequently apply the Jeans equations to these kinematic measurements in order to non-parametrically infer the azimuthally averaged gravitational acceleration field over this volume, and by removing the contribution from baryonic matter, measure the contribution from dark matter. We find that the gravitational potential of the dark matter is nearly spherical with average flattening $q_\Phi ={1.01 \pm 0.06\, }$ between 5 and 20 kpc, and by fitting parametric ellipsoidal density profiles to the acceleration field, we measure the flattening of the dark matter halo over these radii to be $q_\rho ={1.00 \pm 0.09\, }\!.$

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González, Genaro, Albert Samper, and Blas Herrera. "ACOUSTIC SIMULATION OF THE CENTRAL HALL IN PALAU GÜELL BY GAUDÍ." Architecture and Engineering 6, no. 2 (2021): 18–30. http://dx.doi.org/10.23968/2500-0055-2021-6-2-18-30.

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Introduction: Quadric surfaces are commonly used in buildings due to their geometric ability to distribute and focus sound waves. The Central Hall in Palau Güell — a UNESCO World Heritage Site — is topped by an ellipsoidal dome. Antoni Gaudí envisaged this room as a concert hall where the organ and the dome play a lead role. Methods: The two previously mentioned elements are the main subject of our paper, which serves two purposes: 1) determining the values of the acoustic parameters of the hall through onsite measurement and also through simulation, and 2) using the geometric parameters of the quadric surface, which best fits the dome, in order to check whether it is possible to improve the acoustics of the hall by placing a new emission source at the focus of the dome’s ellipsoid. Results and Discussion: Contrary to the authors’ expectations, due to the focal reflection properties of the quadric surface, some acoustic parameters on the listening plane do not improve significantly. Therefore, we conclude that Gaudí took the acoustical impact into account when designing this hall.

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Wang, Chengshu. "Accurate spatial directional derivative: Antialiasing Kirchhoff migration." GEOPHYSICS 69, no. 3 (May 2004): 811–16. http://dx.doi.org/10.1190/1.1759467.

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Applying a low‐pass filter to each input trace before performing migration is a common antialiasing method used in Kirchhoff 3D migration. The spatial directional derivative that gives the tangent plane direction of the reflector is key in determining the antialiasing frequency limits. In this paper, we present the formula of the traveltime gradient for the diffraction hyperboloid. We also deduce the formula of the vertical traveltime gradient for the reflection ellipsoid, which can be used to construct the antialiasing low‐pass filter after migration. The migration stretch is easily computed from the ratio of gradient expressions obtained for the reflection ellipsoid and the diffraction hyperboloid. The gradient formula includes magnitude and direction. The correct direction of the gradient function is from an image point to the dip‐moveout image point (ρ* direction) on the surface. The gradient is not in the direction from the image point to the midpoint (ρ direction) as has been previously concluded. The correct spatial directional derivative along ρ is given, and it is slightly less than the gradient norm. We also prove that the true direction of the tangent plane on the reflection ellipsoid can be determined by the gradient. We introduce the directional derivative value along ρ that can be approximately applied to calculate the high‐frequency limit. Compared with the maximum directional derivative value (gradient norm), the directional derivative is relatively accurate and is much easier to calculate for use in antialiasing. The different results from the new method and the former method are compared. Numerical examples compare the performance of the different formulae.

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Li, Zi Jin, and Jin Liang Xu. "Design of Ellipsoidal Specular Reflectors of 70 kW High-Flux Solar Simulator." Advanced Materials Research 827 (October 2013): 163–68. http://dx.doi.org/10.4028/www.scientific.net/amr.827.163.

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With the constraint of maximum light-concentrating efficiency, we designed a condenser for a 70 kW high-flux solar simulator. The mathematical models of the optical condenser unit and system were established to determine the condenser shape parameters.The Monte Carlo ray-tracing method was applied to compute the the light-concentrating efficiency for the condenser. It is shown that the truncation angle is the major parameter to influence the light-concentrating efficiency.When the truncation angle is 60 degrees, the condenser aberration is balanced by the truncation loss to reach the maximum light-concentrating efficiency.

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