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1
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Przydatność badania ruchomości okienka okrągłego za pomocą Laser Doppler Vibrometer w ocenie rekonstrukcji łańcucha kosteczek słuchowych w tympanoplastykach typu zamkniętego

100%
Sokołowski J., Niemczyk K., Bartoszewicz R., Morawski K., Bruzgielewicz A., Rygalska B.
Polish Journal of Otolaryngology
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2010
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vol. 64
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issue 7
77-80
PL
Round window’s movability measurements with helping of LDV in evaluation of ossicular chain functioning. Aim of study: Quantitive evaluation of round window movability in normal conditions and after malleus stapes assembly reconstruction were aims of the study. Methods and materials: In the experiment there were taken 10 non-frozen temporal bones harvested within 48 hours.Temporal bones specimens were prepared like in closed technique with antromastoidectomy and large posterior tympanotomy. Hearing system before and after MSA reconstruction were evaluated by measurement of round window movement. Measurements were performed at four frequencies: 1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz. Results: In the normal ossicular chain the biggest movability were stated at frequency of 1 kHz. After reconstruction at all frequencies measurements were significantly worse. In reconstructed ears the highest movabilities were stated at frequencies 2000 Hz and 4000 Hz. Conclusions: Round window movability could be measured by Laser Doppler Vibrometry in posterior tympanotomy approach. Before reconstruction the biggest movability were evaluated at 1000 Hz and after MSA at 2000 Hz
2
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Enhanced resonant second harmonic generation in plasma based on density transition

100%
Kant N., Thakur V.
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issue 2
355-360
EN
Resonant second harmonic generation of a relativistic self-focusing laser in plasma with density ramp profile has been investigated. A high intense Gaussian laser beam generates resonant second harmonic beam in plasma with density ramp profile. The second harmonic undergoes periodic focusing in the plasma channel created by the fundamental wave. The normalized second harmonic amplitude varies periodically with distance and attains maximum value in the focal region. Enhancement in the second harmonic amplitude on account of relativistic self-focusing of laser based on plasma density transition is seen. Plasma density ramp plays an important role to make self-focusing stronger which leads to enhance the second harmonic generation in plasma.
3
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Przydatność badania ruchomości okienka okrągłego za pomocą Laser Doppler Vibrometer w ocenie rekonstrukcji łańcucha kosteczek słuchowych w tympanoplastykach typu zamkniętego

100%
Sokołowski J., Niemczyk K., Bartoszewicz R., Morawski K., Bruzgielewicz A., Rygalska B.
Otolaryngologia Polska
|
2010
|
vol. 64(7)
77-80
PL
Round window’s movability measurements with helping of LDV in evaluation of ossicular chain functioning. Aim of study: Quantitive evaluation of round window movability in normal conditions and after malleus stapes assembly reconstruction were aims of the study. Methods and materials: In the experiment there were taken 10 non-frozen temporal bones harvested within 48 hours.Temporal bones specimens were prepared like in closed technique with antromastoidectomy and large posterior tympanotomy. Hearing system before and after MSA reconstruction were evaluated by measurement of round window movement. Measurements were performed at four frequencies: 1000 Hz, 2000 Hz, 4000 Hz, 8000 Hz. Results: In the normal ossicular chain the biggest movability were stated at frequency of 1 kHz. After reconstruction at all frequencies measurements were signifi cantly worse. In reconstructed ears the highest movabilities were stated at frequencies 2000 Hz and 4000 Hz. Conclusions: Round window movability could be measured by Laser Doppler Vibrometry in posterior tympanotomy approach. Before reconstruction the biggest movability were evaluated at 1000 Hz and after MSA at 2000 Hz
4
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Image-to-patient registration by natural anatomical surfaces of the head

88%
Marmulla R., Mühling J., Eggers G.
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2007
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vol. 2
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issue 1
89-102
EN
The use of registration markers in computer-assisted surgery is combined with high logistic costs and efforts. During the preparation of image guided surgery, automated markerless patient-to-image registration based on anatomical surfaces allows a significant reduction of preoperative effort and of the radiation dose the patient is exposed to. Placement and measurement of radio-opaque fiducial markers becomes unnecessary. The usability of face, auricle, maxilla and mandible for surface-based registration to CT image data was investigated. The present study was performed to evaluate the clinical accuracy in finding defined target points within the surgical site after markerless patient registration in image-guided oral and maxillofacial surgery. Preoperatively, the spatial position of 20 patients was registered to CT image data using a 3D laser surface scanner. Indications for surgery were tumours, foreign bodies and skeletal malformations. The accuracy of this surface-based registration was verified using additionally placed fiducial markers. The study showed, that markerless surface-based registration was sufficiently accurate for clinical use when the surface used for matching was the upper jaw, the face, or - with reservations - the auricle. Surface-based registration using the mandible did not yield satisfying results. To conclude, image-to-patient registration based on laser surface scanning is a valuable method for surgery of the head. Multiple sites of the head were identified as appropriate for the method. Hence, dependent on the individual case and the intended surgery, the registration area can be selected with the necessary flexibility.
5
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THE INFLUENCE OF SPRINT BLOCK START ELEMENTS ON INITIAL VELOCITY OF 100 METRE RACE

88%
Terczyński R.
Central European Journal of Sport Sciences and Medicine
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2014
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vol. 8
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issue 4
87-96
EN
The aim of this paper was to investigate whether it is possible to evaluate the relationship between different phases of sprint start objectively. The participants of the research were the top level of elite National Sprint Team (8 female, 9 male). The run times were as follows: 10.39 ±0.12 s for men and 11.63 ±0.20 s for women. The data that were taken into account during the research in order to examine typical kinetic parameters of the sprint start were: reaction time, delay between simple reaction time and reaction time (IAAF), time to front peak force, time to rear peak force, delay between end of front force and gun signal and total start time. The analysis of the study identifies the major kinematic parameters of the phases of the sprint start and block acceleration that influence the results of sprint running. The following correlation analyses were conducted, a linear regression for the typical kinetic parameters of the sprint start, initial speed on 100 metre race. Finally, a simple coaching related model for the development of sprinting is presented which is consistent with scientific evidence recommendations for coaches to make changes in training.
6
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Laser frequency counting and frequency modulation width measurement from a fft signal

88%
Křen P.
Metrology and Measurement Systems
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2012
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issue 3
7
Content available remote

Detection of laser induced dielectric breakdown in water using a laser doppler vibrometer

88%
Saarela J., Löfqvist T., Ramser K., Gren P., Olson E., Niemi J., Sjödahl M.
Open Physics
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2010
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vol. 8
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issue 2
235-241
EN
This study is focused on exploring the feasibility of an all-optic surface scanning method in determining the size and position of a submerged, laser generated, optoacoustic (OA) source. The optoacoustic effect in this case was generated when the absorption of a short electromagnetic pulse in matter caused a dielectric breakdown, a plasma emission flash and a subsequent acoustic wave. In the experiment, a laser pulse with λ = 1064 nm and 12 ns pulse length was aimed at a volume of deionized water. When the laser beam was focused by a f = 16 mm lens, a single dielectric breakdown spot occurred. When a f = 40 mm was used several breakdowns in a row were induced. The breakdowns were photographed using a double shutter camera. The acoustic wave generated by the dielectric breakdowns were detected at a point on the water surface using a laser Doppler vibrometer (LDV). First, the LDV signal was used to calculate the speed of sound with an accuracy of 10 m/s. Secondly, the location and length of the dielectric breakdown was calculated with an accuracy of 1 mm. The calculated position matched the breakdown location recorded by a camera. The results show that it is possible to use LDV surface measurements from a single spot to determine both the position and length of the OA source as well as the speed of sound in the medium. Furthermore, the LDV measurements also show a secondary peak that originates from the OA source. To unravel the origin and properties of this interesting feature, further investigations are necessary
8
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Highly sensitive airborne open path optical hygrometer for upper air measurements – proof of concept

75%
Stacewicz T., Magryta P.
Metrology and Measurement Systems
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2018
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vol. 25
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issue 4
9
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Application of modal control for automobile cruise control

71%
Zbrutsky A., Kaveshgar M., Zbrutsky A., Kaveshgar M.
Archive of Mechanical Engineering
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2011
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vol. 58
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issue 1
10
Content available remote

The role of F A1:Ag+ defects in laser light generation and coadsorption of CO and halogen atoms at the KCl and KBr surface sites. First principles calculations

63%
Abdelrazik S., Shalabi A.
Open Physics
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2007
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vol. 5
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issue 4
611-636
EN
FA1:Ag+ color center at the low coordination (100) and (110) surface sites of KCl and KBr thin films play an important role in providing tunable laser oscillation and adsorbatesubstrate interactions. Double-well potentials at this site are investigated using ab initio molecular electronic structure calculations. The calculated Stokes shifted (optical transition bands), opticaloptical conversion efficiencies, the probability of orientational destruction, exciton (energy) transfer and Glasner-Tompkins empirical rule suggest that laser light generation is sensitive to (i) the lattice anion, (ii) the coordination number of surface ions, and (iii) the choice of the basis set centered on the anion vacancy. The adsorbate-substrate interactions were found to be dependent on the electronegativity of the adatom and on the lattice anion. Optimised geometries and the coadsorption of CO and (F, Cl, Br, I) on KCl and KBr (100) crystals are presented. Calculated chemisorption energies for CO on the (halogen atom/defect free sites of KCl and KBr (100) crystals) showed that the coadsorption of halogen atom tends to block other adsorbate-substrate interactions at the nearest neighbour sites. Thus if halogen atom coverage increases, the CO prefers to be adsorbed on the K+ site of the KCl and KBr (100) surfaces and on KBr relative to KCl.
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