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Summary: For the first time, 3GPP considered in Release‐17 the introduction of mobile satellite service (MSS) frequency bands for 3GPP user equipment (UE) direct connectivity with satellites and had to consider the coexistence in adjacent bands with terrestrial networks (TNs). This paper will further explain the most challenging and the main surprising outcomes of this work, which opened new market opportunities for both terrestrial and nonterrestrial stakeholders. 5G New Radio nonterrestrial networks (NTNs) for satellite communications are representing a major breakthrough in the history of telecommunication for the capability of reuniting two different types of services, that is, terrestrial and nonterrestrial, by reusing the same waveform and potentially the same type of terminal. One of the major conclusions of the 5G NR NTN 3GPP work in Release‐17 was that NTN UE could reuse the current requirements of the TN UE. For this reason, the same terminal can connect to both TNs and to nonterrestrial satellite constellations. Consequently, the market is not fragmented and therefore there will be a real opportunity for both terrestrial and satellite operators to increase the coverage and the quality of the service all over the world. This is one of the most important breakthroughs that 3GPP Release‐17 work was able to justify because it clearly shows that satellite connectivity using 5G NR technology is not only for dedicated satellite 5G NR UE with a higher power class. On the other hand, the 3GPP work also shows that the satellite connectivity does not require a dedicated satellite waveform, because 5G NR waveform based on CP‐OFDM (for downlink) and DFT‐s‐OFDM (for uplink) is sufficient. Another important finding is that TN can coexist with NTN on adjacent channels with relaxed ACIR requirements for the tested simulation scenarios. In fact, the satellite 5G NR requirements are lower when compared with terrestrial base station (BS) requirements from previous 3GPP releases. The satellite ecosystem tremendously changed after these findings, and both satellite and terrestrial stakeholders now see a potential market opportunity. [ABSTRACT FROM AUTHOR]

There is limited evidence of a natural course of an upper gastrointestinal (UGI)-subepithelial lesion (SEL) of 2 cm or less in size. This study aims to determine the natural course of UGI-SELs and find the risk factors of the endoscopic and endoscopic ultrasonography (EUS) findings associated with an increase in size. The medical records of 2539 patients with UGI-SELs between 2004 and 2016 were reviewed retrospectively. A total of 672 SELs of 2 cm or less in size were analyzed through EUS and followed up for at least 36 months. The mean follow-up duration was 68 months (range: 36–190 months), and 97 SELs (14.4%) showed an increase in size with a mean increase rate of 1.2 mm/year. Initial size (aOR 1.03, 95% confidence interval (CI) 1.01–1.06), an endoscopic finding of a hemorrhagic spot (aOR 3.13, 95% CI 1.14–8.60), and an EUS finding of a lesion in the fourth layer (aOR 1.87, 95% CI (1.21–2.88) were related to an increase in size. An endoscopic finding of translucidity (aOR 0.28, 95% CI (0.10–0.76) and an EUS finding of calcification (aOR 0.30, 95% CI 0.09–0.95) were inversely related to an increase in size. There was no death related to UGI-SELs during the follow-up. While most UGI-SELs of 2 cm or less in size showed no significant size change and favorable prognosis, an individualized follow-up strategy needs to be considered in case of the presence of hemorrhagic spots and lesions in the fourth layer. [ABSTRACT FROM AUTHOR]

Fog screens offer a great advantage to be used as scattering screens in three‐dimensional displays. In the absence of a fixed rigid form, fog screens work as screens without any physical obstruction. The density of water droplets can be regulated to adjust the screen's transparency and scattering level. This study proposes a method for crosstalk reduction between adjacent viewing windows by decreasing the divergence of view of the projector, with concentration lenses. By applying the Scheimpflug principle, we also reduce the keystone effect, which occurs when the fog screen is slanted with respect to the optical axis. In this study, we have realized a tabletop multiview fog display without any structures on the table and established that the proposed method is feasible for decreasing crosstalk effectively. [ABSTRACT FROM AUTHOR]

Pool scrubbing occurring in the containment of a nuclear reactor is an important mechanism for radioactive particle removal. In this article, an approximate analytical solution to the equation of particle removal with any possible combination of removal processes is suggested. Assuming that the particle size distribution can be approximated by a log-normal function, the reduction of total particle number and mass, and the changes in average particle size and polydispersity are expressed as explicit functions of their initial values, time, and the removal mechanism parameters. The solution is then applied to a pool scrubbing problem as an application example. The approximate solution derived in this study shows good agreement with the exact solution. The error, caused by an approximation for the slip correction factor, is potentially large only for the intermediate-size particles. However, the absolute error still remains small because the particle removal rate is minimum in that size range. The methodology adopted and the solution derived in this paper will be useful when only particle size distribution parameters are available without full information of whole size distribution. [ABSTRACT FROM AUTHOR]