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The duality between electric and magnetic dipoles in electromagnetism only partly applies to condensed matter. In particular, the elementary excitations of the magnetic and ferroelectric orders, namely magnons and ferrons, respectively, have received asymmetric attention from the condensed matter community in the past. In this Perspective, we introduce and summarize the current state of the budding field of “ferronics.” We argue that the introduction of dipole-carrying elementary excitations allows the modeling of many observables and potentially leads to applications in thermal, information, and communication technologies. 

Radio map describes network coverage and is a practically important tool for network planning in modern wireless systems. Generally, radio strength measurements are collected to construct fine-resolution radio maps for analysis. However, certain protected areas are not accessible for measurement due to physical constraints and security considerations, leading to blanked spaces on a radio map. Non-uniformly spaced measurement and uneven observation resolution make it more difficult for radio map estimation and spectrum planning in protected areas. This work explores the distribution of radio spectrum strengths and proposes an exemplar-based approach to reconstruct missing areas on a radio map. Instead of taking generic image processing approaches, we leverage radio propagation models to determine directions of region filling and develop two different schemes to estimate the missing radio signal power. Our test results based on high-fidelity simulation demonstrate efficacy of the proposed methods for radio map reconstruction. 

Site U1559 (30°15.6336′S, 15°02.0941′W; proposed Site SATL-13A) is in the central South Atlantic Ocean at a water depth of 3055 meters below sea level (mbsl), ~130 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half-spreading rate of ~17.0 mm/y (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]). With an estimated age of 6.6 Ma, Site U1559 is the youngest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). 

Site U1583 (30°42.6175′S, 20°26.0336′W; proposed Site SATL-33B) is in the central South Atlantic Ocean at a water depth of ~4210 meters below sea level (mbsl), ~652 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024b]) on crust that formed at an intermediate half spreading rate of ~24 mm/y, which is close to the highest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024b]). With an estimated age of 30.6 Ma, Site U1583 is close to the median age of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393), and it is closest to the geographic midpoint. 

Site U1561 (30˚43.2902′S, 26˚41.7162′W; proposed Site SATL-55A) is in the central South Atlantic Ocean at a water depth of 4910 meters below sea level (mbsl) ~1250 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half spreading rate of ~13.5 mm/y, which is the slowest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020; see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]). With an estimated age of 61.2 Ma, Site U1561 is the oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1561 sits on a basement ridge and is therefore less heavily sedimented than Sites U1556 and U1557, which are located ~25 km south of Site U1561 on 61.2 and 60.7 Ma ocean crust, respectively. Together, all sites in this region allow for investigation of the effect of sediment thickness on crustal evolution. 

Site U1556 (30°56.5244′S, 26°41.9472′W; proposed Site SATL-53B) is in the central South Atlantic Ocean at a water depth of 5002 meters below sea level (mbsl) ~1250 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half spreading rate of ~13.5 mm/y, which is the slowest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]). With an estimated age of 61.2 Ma, Site U1556 is the oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1556 is less heavily sedimented than Site U1557, which is located 6.5 km east of Site U1556 on 60.7 Ma ocean crust. Together, both sites allow for investigation of the effect of sediment thickness on crustal evolution. 

Site U1560 (30°24.2057′S, 16°55.3702′W; proposed Site SATL-25A) is in the central South Atlantic Ocean at a water depth of ~3723 meters below sea level (mbsl), ~315 km west of the Mid-Atlantic Ridge in the low-productivity South Atlantic Gyre (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024b]). The crust formed at an intermediate half spreading rate of ~25.5 mm/y, which is the highest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024b]). With an estimated age of 15.2 Ma, Site U1560 is the second youngest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1560 is similar in age but is in a contrasting environment to the deep drilling at Ocean Drilling Program (ODP)/Integrated Ocean Drilling Program superfast Site 1256 (Wilson et al., 2006; Expedition 309/312 Scientists, 2006; Expedition 335 Scientists, 2012), which is on crust that formed at the East Pacific Rise during an episode of superfast spreading rate in a region of high pelagic productivity and rapid sedimentation (Shipboard Scientific Party, 2003). 

Site U1557 (30°56.4651′S, 26°37.7892′W, proposed Site SATL-56A) is in the central South Atlantic Ocean at a water depth of ~5011 meters below sea level (mbsl) ~1243 km west of the Mid-Atlantic Ridge (see Figure F1 and Tables T1, T2, all in the Expedition 390/393 summary chapter [Coggon et al., 2024d]) on crust that formed at a slow half spreading rate of ~13.5 mm/y, which is the slowest spreading rate in the study region (Kardell et al., 2019; Christeson et al., 2020) (see Figure F7 in the Expedition 390/393 summary chapter [Coggon et al., 2024d]; Reece et al., 2016; Reece and Estep, 2019). With an estimated age of 60.7 Ma, Site U1557 is just about the oldest location of the South Atlantic Transect (SAT) campaign (International Ocean Discovery Program [IODP] Expeditions 390C, 395E, 390, and 393). Site U1557 is more heavily sedimented than Site U1556, which is located 6.5 km west of Site U1557 on 61.2 Ma ocean crust. Together, both sites allow for investigation of the effect of sediment thickness on crustal evolution. 

This section provides an overview of operations, depth conventions, core handling, curatorial procedures, and analyses performed on the R/V JOIDES Resolution during the International Ocean Discovery Program (IODP) South Atlantic Transect (SAT) Expeditions 390C, 395E, 390, and 393. This information applies only to shipboard work described in the Expedition reports section of the SAT Proceedings of the International Ocean Discovery Program volume. Methods used by investigators for shore-based analyses of expedition samples and data will be described in separate individual postexpedition research publications.