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Image Display And Manipulation In Medical Imaging
Published in Ken Holmes, Marcus Elkington, Phil Harris, Clark's Essential Physics in Imaging for Radiographers, 2021
In addition to DICOM, there are a number of other standards enabling picture archive and communications systems (PACS), as well as wider teleradiolology systems, to operate. Although slightly beyond the remit of this book, some of these standards warrant a mention and include:IEEE 802.3 (ethernet). This stems from computer networks and is associated with the physical layer on which the image data passes (network plugs, sockets, wires, switches and network cards).IEEE 802.5 (token ring). Similar to ethernet standard, except that a ‘token’ is required to gain access to image data. A good example might be a dongle, which is a small device similar to a USB memory stick that has to be physically plugged into a computer in order to access certain images and data.TCP/IP (transmission control protocol/internet protocol). This is a standard to ensure that data are transmitted over the internet without image or data degradation or corruption.HL-7 (Health Level 7) is basically to ensure that a radiology information system (RIS) can talk to PACS and the hospital information system (HIS) systems. It also enables one hospital PACS, RIS and HIS to talk to another hospital’s set-up.
A new infrastructure management software for the optimization of road investments
Published in Hiroshi Yokota, Dan M. Frangopol, Bridge Maintenance, Safety, Management, Life-Cycle Sustainability and Innovations, 2021
The minimum data needed to initiate study of a single structure or system of structures are the following: Data on materials (resistant strength, maximum deformation, etc.);Geometry (length of structural elements, geometrical sections, restraints, etc.);Constructive details (reinforcement steel, unions, etc.);Loads (deriving from the structural code and/or traffic data);Degradation (deriving from visual inspection and/or material tests).
Fundamentals of Ocean Optics
Published in Victor Raizer, Optical Remote Sensing of Ocean Hydrodynamics, 2019
The angular resolution of an optical system is severely limited by atmospheric turbulence (aerosol impact is not considered). Instead diffraction-limited angular resolution αopt ~ λ/D, it will be αatm ~ λ/r0. The reduction is by factor D/r0 which, e.g., for IKONOS imagery is D/r0 ~ 0.7/(0.1 ÷ 0.2) ~ 3 ÷ 7 (note that for regular optical telescope D/r0 ~ 25). For example, in the case of an atmosphere/sensor imaging system with the ratio of D/r0 = 5, the speckle (glitters) patterns will be spread over an area approximately five times larger than the diffraction-limited PSF. The reason of data degradation is optical turbulence which exists even at excellent seeing conditions. It means, in particular, that ocean surface features registered in the optical (IKONOS) images always will comprise some geometrical distortions (blurring effects) due to turbulence-induced changes in pixel resolution. In some situations, this can limit capabilities of thematic data analysis and the detection capacity.
Anisotropic plasma sheath turbulence effects on the mode states of Whittaker–Gaussian beams
Published in Waves in Random and Complex Media, 2023
Nowadays, outdoor wireless optical communication or free-space optical communication (FSOC) is at the forefront of many intriguing applications due to establishing secure, high-bandwidth, cost-effective, and versatile communication between mobile points, and providing comfortable and flexible interconnection through centralized or distributed communication systems [1, 2]. In this regard, recent years have witnessed considerable influence of FSOC technology in developing unmanned aerial vehicles, deep inter-satellite links, high-altitude platforms, aircrafts, up-and-down links between space platforms, and so on [3]. However, the performance of the FSOC systems is affected by some incompatible atmospheric conditions such as turbulence, and these problems pose a major challenge to the FSOC system engineers through data degradation and communication blackout. Actually, turbulent media in most cases come into play with increasing noise which generates crosstalk and imposes serious limitations on FSOC [4, 5].
Influence of Doppler broadening model accuracy in Compton camera list-mode MLEM reconstruction
Published in Inverse Problems in Science and Engineering, 2021
Yuemeng Feng, Jean Michel Létang, David Sarrut, Voichia Maxim
The numerical evaluation of (15) is relatively time consuming (order of minutes) but can be calculated once and saved for further use. If the attenuation factors are neglected, one obtains the model from [27]. When the value of is close to zero, the factor can be replaced with its first order approximation leading to sensitivity model, If we further neglect the variability of the absorption probability in the previous layers, we obtain the model M2 given as that can be partially evaluated as The performances of these two models can be appreciated in Figure 3 where they are compared to Monte-Carlo simulation from point sources emitting at 511 keV. The sources were placed at different positions on (a) a line parallel to the Ox axis at 4 cm for the upper scatterer and (b) on the Oz axis. Only Doppler broadening was simulated as data degradation factor. We obtained qualitatively the same results for realistic data (not shown here), where we considered not only the Doppler broadening, but also the limited spatial and energy resolution as the source of the uncertainties.
Recent research and development programs for infrastructures maintenance, renovation and management in Japan
Published in Structure and Infrastructure Engineering, 2020
Yozo Fujino, Dionysius M. Siringoringo
The system inputs past inspection reports as a PDF format. For paper reports, scans and scanning software are employed to obtain PDF file. From PDF data, text data, degradation photo image data and degradation sketch data are extracted by a software. From degradation sketch, position of degradation is extracted using image recognition software. Character recognition techniques are utilized to identify type of degradation and photographic image. Later, these data are integrated into bridge information model. The information system has function of viewing not only 3 D shape model but also 3 D model with photo texture. By extracting information from the past and associating it with 3 D model, it is easier for bridge operator to create a repair plan. Figure 27 shows the structure of developed web content for the system (Tanaka et al. 2016).