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1.
Rev Sci Instrum ; 94(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37655988

RESUMO

The Ma_MISS miniaturized spectrometer is integrated within the Drilling System of the ExoMars Rosalind Franklin Rover for Mars exploration. Here we focus on the on ground calibration campaign to obtain radiometric and linearity calibrations of the Ma_MISS instrument, while the first paper dealt with the spectral calibration [De Angelis et al., Rev. Sci. Instrum. 93, 123704 (2022)]. The experimental setup used to carry out radiometric calibration is described, as are the methods used for data processing and key parameter retrieval. In particular, the Spectrometer Transfer Function (Responsivity), Signal-to-Noise Ratio, and detector linearity are determined. In a third paper [De Sanctis et al., Planet. Sci. J. 3, 142 (2022)], validation of the Ma_MISS calibration results through spectral measurements performed on rock and synthetic targets during the radiometric calibration campaign is described.

2.
Rev Sci Instrum ; 93(12): 123704, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586927

RESUMO

The Ma_MISS spectrometer is integrated within the drilling system of the Rosalind Franklin ExoMars rover. This paper reports the on-ground calibration campaign performed on the spectrometer. Here, we focus on the spectral calibration of the instrument. The experimental setup used to carry out calibration is described, and the methods used for data processing and key parameters retrieval are explained. In particular, the spectral parameters such as (i) pixel central wavelengths, (ii) spectral response function, (iii) spectral resolution, (iv) sampling, and (v) range are determined. In a follow-up paper, the linearity and radiometric calibrations are described, while in De Sanctis et al. [Planet. Sci. J. 3, 142 (2022)], the validation of spectral measurements performed on synthetic and natural rock targets is presented.

3.
Rev Sci Instrum ; 88(9): 094503, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28964217

RESUMO

The Visible and near Infrared Hyperspectral Imager (VIHI) is the VIS-IR spectrometer with imaging capabilities aboard the ESA BepiColombo mission to Mercury. In this second paper, we report the instrument spectral characterization derived by the calibration campaign carried out before spacecraft integration. Complementary measurements concerning radiometric and linearity responses, as well as geometric performances, are described in Paper I [G. Filacchione et al., Rev. Sci. Instrum. 88, 094502 (2017)]. We have verified the VIHI spectral range, spectral dispersion, spectral response function, and spectral uniformity along the whole slit. Instrumental defects and optical aberrations due to smiling and keystone effects have been evaluated, and they are lower than the design requirement (<1/3 pixel). The instrumental response is uniform along the whole slit, while spectral dispersion is well represented by a second order curve, rather than to be constant along the spectral dimension.

4.
Acta Orthop Belg ; 68(3): 272-8, 2002 Jun.
Artigo em Francês | MEDLINE | ID: mdl-12152375

RESUMO

The authors have retrospectively studied 18 cases of tibiocalcaneal arthrodesis performed to treat a fixed equinovarus deformity of the foot in 13 adult patients. The operations were performed between 1981 and 1998; there were 9 neurologic and 9 post-traumatic deformities. The mean calcaneal varus deformity was 50 degrees and the mean equinus deformity was 75 degrees. The results were evaluated using Kitaoka's criteria. We noted one postoperative cutaneous necrosis, two nonunions, one of which was reoperated by bone freshening and osteotomy of the midfoot. All rearfeet were in neutral alignment and were stable. Shortening was on average 2.8 cm. Plantar support was achieved in 10 feet, with improved autonomy, walking capacity and footwear. Overall, there were 10 good, 2 fair and 1 poor result. In the group with neurologic deformities there were 4 good, 1 fair and 1 poor result. In the group with post-traumatic deformities, there were 6 good and one fair results. Other series published also showed satisfactory results comparable to or better than those obtained with triple arthrodesis, which generates severe stiffness of the rear- and midfoot, disturbing gait. Fixed equinovarus deformity of the foot in the adult is a good indication for tibiocalcaneal arthrodesis, allowing in the majority of cases to achieve stable and painless plantar support.


Assuntos
Artrodese , Calcâneo/cirurgia , Pé Torto Equinovaro/cirurgia , Tíbia/cirurgia , Adulto , Idoso , Artrodese/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Appl Opt ; 29(27): 3938-44, 1990 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-20577317

RESUMO

A simple and inexpensive method of measuring statistical parameters related to the time lengthening arising in the propagation of a light pulse in a turbid medium is presented. The method is based on the repetition of attenuation measurements of a light beam passing through the turbid medium when the absorption coefficient of the medium surrounding the diffusing particles is varied. The measurements are carried out using a cw source and a simple optical receiver with a common photodiode as a detector. The results of two measurements are reported together with the results of numerical simulations carried out using the scattering properties and geometric parameters corresponding to the experimental situation. Numerical results were obtained using a Monte Carlo based method. Good agreement between experimental and numerical results was found.

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