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Статті в журналах з теми "Inhomogenous Imaging"

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Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 28 січня 2023

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1

Crone, M., I. R. Barkshire, M. Prutton, and P. G. Kenny. "Auger imaging from rough, chemically inhomogenous, materials." Surface and Interface Analysis 22, no. 1-12 (July 1994): 581–84. http://dx.doi.org/10.1002/sia.7402201123.

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2

Chiavassa, A., S. Lacour, F. Millour, T. Driebe, M. Wittkowski, B. Plez, E. Thiébaut, et al. "VLTI/AMBER spectro-interferometric imaging of VX Sagittarii's inhomogenous outer atmosphere." Astronomy and Astrophysics 511 (February 2010): A51. http://dx.doi.org/10.1051/0004-6361/200913288.

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3

Siarkowski, M. "Imaging stellar coronae from eclipsing binary X-ray light curves." Symposium - International Astronomical Union 176 (1996): 469–76. http://dx.doi.org/10.1017/s0074180900083480.

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Анотація:

The Sun is the only star whose X-ray emitting, strongly inhomogenous corona can be spatially resolved via direct observations. For other late type-stars it is known that coronae do exist, but the spatial distribution of their emission is largely unknown. However in the case of eclipsing binaries this spatial structure can be potentially deduced from the orbital modulation of the observed X-ray light curve. The best candidates for this kind of analysis are RS CVn binaries, the most active and luminous late-type X-ray coronal sources. These are detached binaries with periods typically between 0.5 and 20 days, in which one or both stars have evolved into subgiant or giant of spectral type G or K. For short orbital periods (< 14 days) the tidal forces lead to synchronization of the orbital and rotational periods, so these systems rotate rigidly.

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4

Lu, Pan, and Panagiotis Kosmas. "Three-Dimensional Microwave Head Imaging with GPU-Based FDTD and the DBIM Method." Sensors 22, no. 7 (March 31, 2022): 2691. http://dx.doi.org/10.3390/s22072691.

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We present a preliminary study of microwave head imaging using a three-dimensional (3-D) implementation of the distorted Born iterative method (DBIM). Our aim is to examine the benefits of using the more computationally intensive 3-D implementation in scenarios where limited prior information is available, or when the target occupies an area that is not covered by the imaging array’s transverse planes. We show that, in some cases, the 3-D implementation outperforms its two-dimensional (2-D) counterpart despite the increased number of unknowns for the linear problem at each DBIM iteration. We also discuss how the 3-D algorithm can be implemented efficiently using graphic processing units (GPUs) and validate this implementation with experimental data from a simplified brain phantom. In this work, we have implemented a non-linear microwave imaging approach using DBIM with GPU-accelerated FDTD. Moreover, the paper offers a direct comparison of 2-D and 3-D microwave tomography implementations for head imaging and stroke detection in inhomogenous anatomically complex numerical head phantoms.

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5

Kantilaras, Anggita Putri. "Role of Ultrasound in the Diagnosis Approach of Malignant Solitary Fibrous Tumor." Journal of Diagnostic Medical Sonography 34, no. 5 (July 23, 2018): 391–95. http://dx.doi.org/10.1177/8756479318781779.

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This is a case study of solitary fibrous tumor (SFT), which is a rare neoplasm of mesenchymal origin that comprises less than 2% of all soft tissue tumors. SFT located in the extremities, especially in the legs, has a high possibility of developing malignancy. The case study presented demonstrates a sonogram which identified an inhomogenous hypoechoic solid lesion located in the subcutaneous layer of the femoral region. The use of Doppler showed hypervascular activity in the hyperechoic area. This finding was consistent with malignant SFT and confirmed by histopathologic exam. The possibility of an SFT should be a diagnostic consideration with any large soft tissue mass in extremities. This is a further consideration with the diagnostic medical sonography findings demonstrating a hypoechoic, well-defined mass that has a large collateral feeding vessel and displaces the adjacent structures.

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6

Krohn, T., A. Ghassemi, M. Gerressen, F. A. Verburg, F. M. Mottaghy, and F. F. Behrendt. "Bone graft scintigraphy." Nuklearmedizin 51, no. 05 (2012): 201–4. http://dx.doi.org/10.3413/nukmed-0469-12-01.

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Summary Aim: To evaluate a scintigraphic tool for intra - operative assessment of vascularized bone graft perfusion before and after transplantation. Patients, methods: This pilot study included three patients scheduled for surgical segmental mandibulectomy followed by reconstruction with a vascularized iliac bone graft. A continuous 99mTc-pertechnetate infusion was applied selectively arterial into the blood vessel supplying the respective graft before osteotomy as well as after transplantation. Perfusion was analysed by scintigrams acquired using the intraoperative camera systems declipseSPECT and Sentinella. Results were compared qualitatively. Results: Before harvesting the graft, intraoperative scintigraphy revealed a clearly delineated area of the iliac crest with a relatively homogenous pertechnetate distribution representing good perfusion. After osteotomy, transplantation to the mandibula and re-anastomosis of the nutrient vessels, scintigraphy in all patients showed a moderately inhomogenous distribution pattern of the pertechnetate indicating an adequate perfusion of the bone transplant through the arterial anastomosis. Conclusion: Intraoperative assessment of bone graft perfusion is possible with the imaging systems Sentinella as well as with declipse SPECT using a continuous intra-arterial infusion of 99mTc-pertechnetate.

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7

Krška, Zdeněk, Jan Šváb, David Hoskovec, and Jan Ulrych. "Pancreatic Cancer Diagnostics and Treatment – Current State." Prague Medical Report 116, no. 4 (2015): 253–67. http://dx.doi.org/10.14712/23362936.2015.65.

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Pancreatic ductal adenocarcinoma (PDAC) represents permanent and ever rising issue worldwide. Five-year survival does not exceed 3 to 6%, i.e. the worst result among solid tumours. The article evaluates the current state of PDAC diagnostics and treatment specifying also development and trends. Percentage of non-resectable tumours due to locally advanced or metastatic condition varies 60–80%, mostly over 80%. Survival with non-resectable PDAC is 4 to 8 months (median 3.5). In contrast R0 resection shows the survival 18–27 months. Laboratory and imaging screening methods are not indicated on large scale. Risk factors are smoking, alcohol abuse, chronic pancreatitis, diabetes mellitus. Genetic background in most PDAC has not been detected yet. Some genes connected with high risk of PDAC (e.g. BRCA2, PALB2) have been identified as significant and highly penetrative, but link between PDAC and these genes can be seen only in 10–20%. This article surveys perspective oncogenes, tumour suppressor genes, microRNA. Albeit CT is still favoured over other imaging methods, involvement of NMR rises. Surgery prefers the “vessel first” approach, which proves to be justified especially in R0 resection. According to EBM immunotherapy same as radiotherapy are not significant in PDAC treatment. Chemotherapy shows limited importance in conversion treatment of locally advanced or borderline tumours or in case of metastatic spread. Unified procedures cannot be defined due to inhomogenous arrays. Surgical resection is the only chance for curative treatment of PDAC and depends mainly on timely indication for surgery and quality of multidisciplinary team in a high-volume centre.

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8

Lischka, F. W., and D. Schild. "Standing calcium gradients in olfactory receptor neurons can be abolished by amiloride or ruthenium red." Journal of General Physiology 102, no. 5 (November 1, 1993): 817–31. http://dx.doi.org/10.1085/jgp.102.5.817.

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Digital imaging and the patch clamp technique were used to investigate the intracellular calcium concentration in olfactory receptor neurons using the Ca2+ indicator dyes fura-2 and fura-2/AM. The spatial distribution of Cai2+ as well as its modification by the drugs Amiloride and Ruthenium Red were studied. Resting calcium concentrations in cells loaded with fura-2/AM were between 10 and 200 nM. In cells that were loaded with the pentapotassium salt of fura-2 through the patch pipette, calcium concentrations were in the same range if ATP was added to the pipette solution. Otherwise, Ca2+ reached concentrations of approximately 500 nM. Most of the observed cells showed a standing gradient of calcium, the calcium concentrations in the distal dendritic end of the cell being higher than in the soma. In some cells, the gradient was markedly reduced or abolished by adding either Amiloride or Ruthenium Red to the bath solution. In a few cells, neither drug had any effect upon the gradient. It is suggested that the inhomogenous spatial distribution of intracellular calcium in olfactory cells of Xenopus laevis is brought about by an influx of calcium ions through two different calcium permeable conductances in the peripheral compartments of the cells. The fact that only either Ruthenium Red or Amiloride abolished the standing calcium gradient further suggested that the two conductances blocked were presumably not coexpressed in the same cells.

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9

Čapek, Martin, Michaela Blažíková, Ivan Novotný, Helena Chmelová, David Svoboda, Barbora Radochová, Jiří Janáček, and Ondrej Horváth. "The Wavelet-Based Denoising Of Images in Fiji, With Example Applications in Structured Illumination Microscopy." Image Analysis & Stereology 40, no. 1 (April 9, 2021): 3–16. http://dx.doi.org/10.5566/ias.2432.

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Filtration of super-resolved microscopic images brings often troubles with removing undesired image parts like, e.g., noise, inhomogenous background and reconstruction artifacts. Standard filtration techniques, e.g., convolution- or Fourier transform-based methods are not always appropriate, since they may lower image resolution that was acquired by hi-tech and expensive microscopy systems. Thus, in this article it is proposed to filter such images using discrete wavelet transform (DWT). Newly developed Wavelet_Denoise plugin for free available Fiji software package demonstrates important possibilities of applying DWT to images: Decomposition of a filtered picture using various wavelet filters and levels of details with showing decomposed images and visualization of effects of back transformation of the picture with chosen level of suppression or denoising of wavelet coefficients. The Fiji framework allows, for example, using a plethora of various microscopic image formats for data opening, users can easily install the plugin through a menu command and the plugin supports processing 3D images in Z-stacks. The application of the plugin for removal of reconstruction artifacts and undesirable background in images acquired by super-resolved structured illumination microscopy is demonstrated as well.

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10

Gutman, S., and M. Klibanov. "Three-dimensional inhomogeneous media imaging." Inverse Problems 10, no. 6 (December 1, 1994): L39—L46. http://dx.doi.org/10.1088/0266-5611/10/6/002.

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11

Pichot, C., L. Jofre, G. Peronnet, and J. Bolomey. "Active microwave imaging of inhomogeneous bodies." IEEE Transactions on Antennas and Propagation 33, no. 4 (April 1985): 416–25. http://dx.doi.org/10.1109/tap.1985.1143603.

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12

Epstein, Charles L. "Magnetic resonance imaging in inhomogeneous fields." Inverse Problems 20, no. 3 (March 19, 2004): 753–80. http://dx.doi.org/10.1088/0266-5611/20/3/007.

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13

Muratikov, K. L. "Laser photoacoustic imaging of inhomogeneous objects." Technical Physics Letters 30, no. 11 (November 2004): 956–58. http://dx.doi.org/10.1134/1.1829354.

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14

Nachman, Adrian I., Lassi Päivärinta, and Ari Teirilä. "On imaging obstacles inside inhomogeneous media." Journal of Functional Analysis 252, no. 2 (November 2007): 490–516. http://dx.doi.org/10.1016/j.jfa.2007.06.020.

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15

Wang, Hexiang, Zhenyou Liu, Yong Zhang, Feng Hou, Weiwei Fu, Jizheng Lin, Yingchao Liu, and Xuejun Liu. "Additional Diagnostic Value of Unenhanced Computed Tomography plus Diffusion-Weighted Imaging Combined with Routine Magnetic Resonance Imaging Findings of Early-Stage Gliblastoma." BioMed Research International 2020 (February 18, 2020): 1–7. http://dx.doi.org/10.1155/2020/1672736.

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Анотація:

Purpose. This study was performed to determine whether diffusion-weighted imaging (DWI) plus unenhanced computed tomography (CT) of the brain increases the diagnostic value of routine magnetic resonance (MR) imaging findings of early-stage glioblastoma. Methods. Postcontrast MR images of eight unenhanced lesions that had been pathologically diagnosed as glioblastoma were retrospectively examined. The location, margin, signal intensity, and attenuation on MR imaging and CT were assessed. Results. On MR imaging, all lesions were ill-defined, small, and isointense to hypointense on T1-weighted images and hyperintense on T2-weighted images. Four patients had perilesional edema. In seven patients, DWI showed an inhomogeneous hyperintense lesion (n = 1) or isointense lesion with a hyperintense region (n = 6). On unenhanced CT, all masses presented as a hypoattenuated lesion with a hyperattenuated region (n = 7) or isoattenuated region (n = 1). The hyperattenuated region (n = 6) or isoattenuated region (n = 1) on CT appeared on DWI as an inhomogeneous hyperintense lesion (n = 1), isointense lesion with a hyperintense region (n = 3), or ring-like peritumoral hyperintensity (n = 3). Conclusions. MR imaging was the most sensitive imaging method for depicting early-stage glioblastoma. The CT finding of a hyperattenuated or isoattenuated region combined with the DWI finding of the same region containing an inhomogeneous hyperintense lesion or isointense lesion with a hyperintense region may be a specific diagnostic sign for early-stage glioblastoma. DWI plus unenhanced CT added diagnostic value to the routine MR imaging findings of early-stage glioblastoma.

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16

Zhang, Ruming, and Bo Zhang. "Near-field imaging of periodic inhomogeneous media." Inverse Problems 30, no. 4 (February 28, 2014): 045004. http://dx.doi.org/10.1088/0266-5611/30/4/045004.

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17

Guign�, J. Y., and V. H. Chin. "Acoustic imaging of an inhomogeneous sediment matrix." Marine Geophysical Researches 11, no. 4 (1989): 301–17. http://dx.doi.org/10.1007/bf00282580.

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18

Ailion, David C. "Potential industrial applications of inhomogeneous broadening imaging." Magnetic Resonance Imaging 10, no. 5 (January 1992): 799–808. http://dx.doi.org/10.1016/0730-725x(92)90415-v.

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19

BALDASSARI, LORENZO. "Scattering coefficients of inhomogeneous objects and their application in target classification in wave imaging." European Journal of Applied Mathematics 31, no. 4 (July 3, 2019): 553–73. http://dx.doi.org/10.1017/s0956792519000160.

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The aim of this paper is to provide and numerically test in the presence of measurement noise a procedure for target classification in wave imaging based on comparing frequency-dependent distribution descriptors with precomputed ones in a dictionary of learned distributions. Distribution descriptors for inhomogeneous objects are obtained from the scattering coefficients. First, we extract the scattering coefficients of the (inhomogeneous) target from the perturbation of the reflected waves. Then, for a collection of inhomogeneous targets, we build a frequency-dependent dictionary of distribution descriptors and use a matching algorithm in order to identify a target from the dictionary up to some translation, rotation and scaling.

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20

Moharamzad, Yashar, Morteza Sanei Taheri, Farhad Niaghi, and Elham Shobeiri. "Brainstem glioma: Prediction of histopathologic grade based on conventional MR imaging." Neuroradiology Journal 31, no. 1 (November 17, 2017): 10–17. http://dx.doi.org/10.1177/1971400917743099.

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Objective The objective of this article is to investigate the association between specific MR imaging findings and histopathologic grading (low-grade vs. high-grade) of brainstem gliomas (BSGs). Methods Sixty-two males and 34 females (mean (standard deviation, SD) age of 24.61 (17.20) years, range = 3 to 70 years) with histologically diagnosed BSG underwent conventional 1.5 T MR imaging, which included T1-weighted (T1W), T2W, and post-contrast T1W sequences. There were 39 children (mean age of 9.38 years) and 57 adults (mean age of 35 years). A binary logistic regression analysis was used to explore associations between MRI features and histopathological grade of the BSG. Results Binary logistic regression revealed that necrosis (adjusted odds ratio (OR) = 16.07; 95% confidence interval (CI) = 3.20 to 80.52; p = 0.001) and inhomogeneous contrast enhancement (adjusted OR = 8.04; 95% CI = 1.73 to 37.41; p = 0.008) as significant predictors of high-grade BSG. The equation (Nagelkerke R2 = 0.575) is Logit ( p high-grade BSG) = (2.77 × necrosis) + (2.08 × heterogeneous contrast enhancement) – 3.13. Sensitivity and specificity values were respectively 66.7% and 96.0% for necrosis and 85.7% and 65.9% for inhomogeneous contrast-enhancing lesions. In the pediatric age group, only inhomogeneous contrast enhancement (adjusted OR = 40; 95% CI = 3.95 to 445.73; p = 0.002) was a significant predictor for high-grade BSG. Conclusion Conventional MR imaging features such as necrosis and inhomogeneous contrast enhancement in adults and heterogeneous contrast enhancement in children suggest high-grade BSG.

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21

Blümich, B. "Wideline 2H -NMR Spectroscopy and Imaging of Solids." Zeitschrift für Naturforschung A 49, no. 1-2 (February 1, 1994): 19–26. http://dx.doi.org/10.1515/zna-1994-1-206.

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Abstract Recent developments, focussing on reduction of the rf excitation power by stochastic excitation, on improvements in sensitivity and excitation bandwidth by magic angle spinning, and on combining wideline spectroscopy with spatial resolution for investigations o f spatially inhomogeneous objects are reviewed.

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22

Hunziker, P., V. F. Kravchenko, A. V. Morozov, E. V. Volosyuk, V. K. Volosyuk, and S. S. Zhyla. "Holographic Imaging Of Inhomogeneous Semitransparent Media: Method Analysis." Физические основы приборостроения 5, no. 3 (September 15, 2016): 78–91. http://dx.doi.org/10.25210/jfop-1603-078091.

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23

Casanova, F., J. Perlo, B. Blümich, and K. Kremer. "Multi-echo imaging in highly inhomogeneous magnetic fields." Journal of Magnetic Resonance 166, no. 1 (January 2004): 76–81. http://dx.doi.org/10.1016/j.jmr.2003.09.008.

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24

Epstein, Charles L., and Jeremy Magland. "A novel technique for imaging with inhomogeneous fields." Journal of Magnetic Resonance 183, no. 2 (December 2006): 183–92. http://dx.doi.org/10.1016/j.jmr.2006.08.012.

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25

Paquin, Raphael, Philippe Pelupessy, and Geoffrey Bodenhausen. "Cross-encoded magnetic resonance imaging in inhomogeneous fields." Journal of Magnetic Resonance 201, no. 2 (December 2009): 199–204. http://dx.doi.org/10.1016/j.jmr.2009.09.008.

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26

Yokota, Takayoshi, Takuso Sato, and Makoto Hirama. "Active incoherent ultrasonic imaging through an inhomogeneous layer." Journal of the Acoustical Society of America 77, no. 1 (January 1985): 144–52. http://dx.doi.org/10.1121/1.392278.

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27

Smith, P. R., J. D. Cashion, and L. J. Brown. "Imaging Mössbauer spectroscopic measurements of an inhomogeneous sample." Hyperfine Interactions 71, no. 1-4 (April 1992): 1503–6. http://dx.doi.org/10.1007/bf02397368.

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28

Fink, M. "Imaging through inhomogeneous media using time reversal mirrors." Ultrasonic Imaging 13, no. 2 (April 1991): 199. http://dx.doi.org/10.1016/0161-7346(91)90109-u.

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29

Novikov, S., and A. Polikanin. "Calculation Method of the Thermal-Imaging Equipment Peration Range Based on the United Parameters: the Temperature Sensitivity and Resolution." Proceedings of Telecommunication Universities 5, no. 4 (2019): 6–14. http://dx.doi.org/10.31854/1813-324x-2019-5-4-6-14.

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The article presents calculating methodology for the detection range, recognition and identification of a thermal-imaging equipment based on threshold temperature sensitivity and temperature resolution, including the cases when working on an inhomogeneous temperature field. The calculating methodology analysis of the action range for thermal-imaging equipment is presented with the initial data choice of the transfer characteristics links models of the thermal imaging system, object, atmosphere and human eye, computational studies are carried out.

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30

Ferrière, Robert, Serge Mensah, and Jean-Pierre Lefebvre. "Weakly Inhomogeneous Media Tomography." Ultrasonic Imaging 25, no. 2 (April 2003): 122–33. http://dx.doi.org/10.1177/016173460302500204.

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Our objective is to develop an ultrasonic scanner for breast imaging. High resolution is obtained by using wide-band spherical waves transmitted and measured in the near field zone (i.e., close to the skin) all around the organ. The tomographic approach that we adopt allows us to use low central frequency waves (3–7 MHz) that are suitable for good penetration while maintaining high resolution and contrast. The procedure is thus suitable for early detection of tumors and increases the chances of total recovery. The novelty of the present reconstruction procedure is that it associates the signals acquired in transmission to the data measured in reflection over a large aperture. This enables us to correct the phase aberration induced by weak inhomogeneities whose sizes might be several wavelengths. Numerical tests based on Finite Difference Time Domain (FDTD) simulations demonstrate the greater fidelity of the reconstruction.

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31

Noël, S., K. Bramstedt, H. Bovensmann, J. P. Burrows, C. Standfuss, E. Dufour, and B. Veihelmann. "Quantification and mitigation of the impact of scene inhomogeneity on Sentinel-4 UVN UV-VIS retrievals." Atmospheric Measurement Techniques Discussions 5, no. 2 (March 1, 2012): 2043–75. http://dx.doi.org/10.5194/amtd-5-2043-2012.

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Abstract. The quality of trace gas products derived from measurements of a space-borne imaging spectrometer is affected by the inhomogeneity of the illumination of the instrument slit and thus by the heterogeneity of the observed scene. This paper aims to quantify this effect and summarise findings on how to mitigate the impact of inhomogeneous slit illumination on tropospheric O3, NO2, SO2 and HCHO columns derived from measurements of the Sentinel-4 UVN imaging spectrometer. For this purpose, spectra for inhomogeneous ground scenes have been simulated based on a combination of a radiative transfer model and spatially high resolved MODIS (Moderate Resolution Imaging Spectroradiometer) data. The resulting errors on tropospheric O3, NO2, SO2 and HCHO columns derived from these spectra have been determined via an optimal estimation approach. It could be concluded that inhomogeneous illumination results in significant errors in the data products if the natural inhomogeneity of the observed scenes is not accounted for. O3 columns are less affected than the other data products; largest errors occur for NO2 (mean absolute errors about 5%, maximum error exceeding 50%). These errors may be significantly reduced (by factors up to >10) by an appropriate wavelength calibration applied individually to each Earthshine radiance spectrum. With wavelength calibration the estimated mean absolute errors due to inhomogeneity are for all gases well below 1%; maximum errors are about 10% for NO2 and around 5% for the other gases.

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32

Marhabaie, Sina, Geoffrey Bodenhausen, and Philippe Pelupessy. "Susceptibility contrast by echo shifting in spatially encoded single-scan MRI." Physical Chemistry Chemical Physics 19, no. 22 (2017): 14210–13. http://dx.doi.org/10.1039/c7cp01898c.

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By modifying an established hybrid imaging sequence called Rapid Acquisition by Sequential Excitation and Refocusing (RASER) so as to obtain Echo-Shifted RASER sequences, we show how one can tune the contrast due to inhomogeneous Tinh2 decay.

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33

MATSUMOTO, Satoshi. "Imaging of Inhomogeneous Structure Based on Seismic Array Observations." Zisin (Journal of the Seismological Society of Japan. 2nd ser.) 54, no. 1 (2001): 193–201. http://dx.doi.org/10.4294/zisin1948.54.1_193.

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34

Sutton, George W. "Effect of inhomogeneous turbulence on imaging through turbulent layers." Applied Optics 33, no. 18 (June 20, 1994): 3972. http://dx.doi.org/10.1364/ao.33.003972.

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35

Bona, A., and D. Cooke. "Velocity-less imaging of linearly inhomogeneous media in 3D." ASEG Extended Abstracts 2009, no. 1 (2009): 1. http://dx.doi.org/10.1071/aseg2009ab003.

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36

Christopher, Ted. "Finite Amplitude Distortion-Based Inhomogeneous Pulse Echo Ultrasonic Imaging." Journal of the Acoustical Society of America 129, no. 4 (2011): 2357. http://dx.doi.org/10.1121/1.3582214.

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37

Papadopoulos, Theseus G., and Ioannis T. Rekanos. "Time-Domain Microwave Imaging of Inhomogeneous Debye Dispersive Scatterers." IEEE Transactions on Antennas and Propagation 60, no. 2 (February 2012): 1197–202. http://dx.doi.org/10.1109/tap.2011.2173150.

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38

Christopher, T. "Finite amplitude distortion-based inhomogeneous pulse echo ultrasonic imaging." IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control 44, no. 1 (January 1997): 125–39. http://dx.doi.org/10.1109/58.585208.

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39

Christopher, Ted. "Finite amplitude distortion-based inhomogeneous pulse echo ultrasonic imaging." Journal of the Acoustical Society of America 126, no. 3 (2009): 1649. http://dx.doi.org/10.1121/1.3230490.

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40

Wise, W. D., Kamalesh Chatterjee, M. C. Boyer, Takeshi Kondo, T. Takeuchi, H. Ikuta, Zhijun Xu, et al. "Imaging nanoscale Fermi-surface variations in an inhomogeneous superconductor." Nature Physics 5, no. 3 (January 25, 2009): 213–16. http://dx.doi.org/10.1038/nphys1197.

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41

Ahola, S., J. Perlo, F. Casanova, S. Stapf, and B. Blümich. "Multiecho sequence for velocity imaging in inhomogeneous rf fields." Journal of Magnetic Resonance 182, no. 1 (September 2006): 143–51. http://dx.doi.org/10.1016/j.jmr.2006.06.017.

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42

Hall, Laurance D., Timothy J. Norwood, and Steve C. R. Williams. "Coupled-spin-filtered imaging in an inhomogeneous magnetic field." Journal of Magnetic Resonance (1969) 79, no. 2 (September 1988): 363–68. http://dx.doi.org/10.1016/0022-2364(88)90232-6.

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43

Jorand, Raphael, Gwénaële Le Corre, Jordi Andilla, Amina Maandhui, Céline Frongia, Valérie Lobjois, Bernard Ducommun, and Corinne Lorenzo. "Deep and Clear Optical Imaging of Thick Inhomogeneous Samples." PLoS ONE 7, no. 4 (April 25, 2012): e35795. http://dx.doi.org/10.1371/journal.pone.0035795.

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44

Christopher, Ted. "Finite amplitude distortion-based inhomogeneous pulse echo ultrasonic imaging." Journal of the Acoustical Society of America 120, no. 2 (2006): 584. http://dx.doi.org/10.1121/1.2336714.

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45

Christopher, Ted. "Finite amplitude distortion-based inhomogeneous pulse echo ultrasonic imaging." Journal of the Acoustical Society of America 121, no. 3 (2007): 1291. http://dx.doi.org/10.1121/1.2720073.

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46

Bansal, Navin, and Ray L. Nunnally. "Improved MR imaging in extremely inhomogeneous radio-frequency fields." Magnetic Resonance Imaging 9, no. 1 (January 1991): 61–65. http://dx.doi.org/10.1016/0730-725x(91)90097-6.

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47

Kim, Jae K., Donald B. Plewes, and Ross Henkelman. "5309101 Magnetic resonance imaging in an inhomogeneous magnetic field." Magnetic Resonance Imaging 13, no. 1 (January 1995): XXV. http://dx.doi.org/10.1016/0730-725x(95)90101-a.

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48

Zhang, Qiang, Hiroyuki Toda, Masakazu Kobayashi, Yoshio Suzuki, and Kentaro Uesugi. "Three Dimensional Microstructure Characterization of an Al-Zn-Mg Alloy Foam Using Synchrotron X-Ray Microtomography." Materials Science Forum 654-656 (June 2010): 2358–61. http://dx.doi.org/10.4028/www.scientific.net/msf.654-656.2358.

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Анотація:

Synchrotron X-ray microtomography (SPring-8, Japan) has been used for the microstructure characterization in a closed cell Al-Zn-Mg alloy foam. Some sophisticated microstructure features, such as micropores and intermetallic particles inside the cell wall, were visualized and quantified three dimensionally(3D) by the high-resolution phase contrast imaging technique. By microtomographies tuned to energies above and below the Zn K-absorption edge, the 3D quantitation of Zn distribution was obtained using subtraction imaging technique. It has been clarified that the Zn distribution was inhomogeneous in the cell wall of the foam. And the agglomeration of Zn-bearing particles was confirmed to induce the brittle fracture of cell wall. The distributions of Ti and Ca in the foam were also visualized by subtraction method. The current tomographic techniques provide novel solutions for the 3D microstructure analysis in the highly inhomogeneous foam materials.

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49

Lucchi, John, Mauro Martinez, and Matthieu Baudelet. "Homogenization of Plasma Emission Collection for Multichannel Spectrometers." Applied Spectroscopy 73, no. 10 (June 20, 2019): 1228–36. http://dx.doi.org/10.1177/0003702819843992.

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Laser-induced breakdown spectroscopy (LIBS) has recently demonstrated its unrivaled performance for broadband elemental imaging of surfaces. The dimensions of the laser sampling spot still being potentially larger than the interfaces of chemical domains, the plasma created at each location can be largely varying and inhomogeneous with contributions from the different sides of the interface. This variation can become problematic when imaging it on fiber bundles connected to multiple spectrometers. A spatially heterogeneous signal would lead to spatially dependent image on the fiber bundle causing inconsistent readings and loss of efficiency. Köhler illumination is used in this study to create a homogenous illumination, regardless of the source homogeneity, thus improving light collection efficiency. The performance of this approach was demonstrated with inhomogeneous spectral sources and applied to the LIBS analysis of a metallic interface, showing up to a sixfold improvement of the homogeneity of the plasma collection.

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50

Noël, S., K. Bramstedt, H. Bovensmann, K. Gerilowski, J. P. Burrows, C. Standfuss, E. Dufour, and B. Veihelmann. "Quantification and mitigation of the impact of scene inhomogeneity on Sentinel-4 UVN UV-VIS retrievals." Atmospheric Measurement Techniques 5, no. 6 (June 11, 2012): 1319–31. http://dx.doi.org/10.5194/amt-5-1319-2012.

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Abstract. The quality of trace gas products derived from measurements of a space-borne imaging spectrometer is affected by the inhomogeneity of the illumination of the instrument slit and thus by the heterogeneity of the observed scene. This paper aims to quantify this effect and summarise findings on how to mitigate the impact of inhomogeneous slit illumination on tropospheric O3, NO2, SO2 and HCHO columns derived from measurements of the Sentinel-4 UVN imaging spectrometer. For this purpose, spectra for inhomogeneous ground scenes have been simulated based on a combination of a radiative transfer model and spatially high resolved MODIS (Moderate Resolution Imaging Spectroradiometer) data. The resulting errors on tropospheric O3, NO2, SO2 and HCHO columns derived from these spectra have been determined via an optimal estimation approach. We conclude that inhomogeneous illumination results in significant errors in the data products if the natural inhomogeneity of the observed scenes are not accounted for. O3 columns are less affected than the other data products; largest errors occur for NO2 (mean absolute errors about 5%, maximum error exceeding 50%, standard deviation of the errors about 8%). These errors may be significantly reduced (by factors up to about 10) by an appropriate wavelength calibration applied individually to each Earthshine radiance spectrum. With wavelength calibration the estimated mean absolute errors due to inhomogeneity are for all gases well below 1%; standard deviations of the errors are 1.5% or lower; maximum errors are about 10% for NO2 and around 5% for the other gases.

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