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Kplo-MAGnetometer (KMAG) is one of the scientific instruments of Korea Pathfinder Lunar Orbiter (KPLO) set to be launched in 2022. Its objectives are magnetic field investigation and technical demonstration near the surface of the Moon. Specifically, it will investigate the lithospheric magnetism of the Moon and measure the electromagnetic wave properties near the lunar surface. It consists of three fluxgate magnetometers on a 1.2 m long boom, which is relatively shorter than the boom used in other missions. The three magnetometers are included for scientific measurements, redundancy checks, and multi-sensor technical investigation. The magnetometers and an inner Anisotropic Magneto-Resistive sensor perform simultaneous sampling to correct for the magnetic field interference caused by the spacecraft. The fully integrated flight model assembly showed that the magnetometer noise level was less than 30 pT Hz−1/2 at 1 Hz and stability was within ±0.2 nT at the 10 Hz sampling rate. This paper describes the configuration and performance of the KMAG using the multi-sensing method. KPLO, THEMIS-ARTEMIS spacecraft, and Commercial Lunar Payload Service modules will be in their operational phase simultaneously. Therefore, the KMAG will be able to contribute to multi-site in-situ measurements of the lunar magnetic field. We expect that the KMAG will provide an up-to-date lunar observation data set and an opportunity to perform the multi-sensor observation.

Many small and medium enterprises (SMEs) want to introduce recommendation services to boost sales, but they need to have sufficient amounts of data to introduce these recommendation services. This study proposes an extrapolative collaborative filtering (ECF) system that does not directly share data among SMEs but improves recommendation performance for small and medium-sized companies that lack data through the extrapolation of data, which can provide a magical experience to users. Previously, recommendations were made utilizing only data generated by the merchant itself, so it was impossible to recommend goods to new users. However, our ECF system provides appropriate recommendations to new users as well as existing users based on privacy-preserved payment transaction data. To accomplish this, PP2Vec using Word2Vec was developed by utilizing purchase information only, excluding personal information from payment company data. We then compared the performances of single-merchant models and multi-merchant models. For the merchants with more data than SMEs, the performance of the single-merchant model was higher, while for the SME merchants with fewer data, the multi-merchant model’s performance was higher. The ECF System proposed in this study is more suitable for the real-world business environment because it does not directly share data among companies. Our study shows that AI (artificial intelligence) technology can contribute to the sustainability and viability of economic systems by providing high-performance recommendation capability, especially for small and medium-sized enterprises and start-ups.

Background: The optimal treatment for distal tibial fractures remains a matter of debate. Nonetheless, plate osteosynthesis produces favorable results to intramedullary stabilization in aspects of alignment restoration. Aim: The aim of the study was to compare the radiologic and clinical outcomes of distal metadiaphyseal tibial fracture between a simple/wedge fracture (SWF) and a comminuted fracture (CF) using minimally invasive plate osteosynthesis (MIPO). Patients and Methods: This retrospective study analyzed patients with SWF or CF of the distal tibial metadiaphysis that was surgically treated with a locking compression plate. Postoperative radiographic assessments and the time to radiologic union were noted. Clinical assessments were evaluated using both the American Orthopedic Foot and Ankle Society (AOFAS) ankle–hindfoot score and the foot function index (FFI). Postoperative complications were documented. Results: Seventy-one cases were analyzed over a mean follow-up period of 20.9 months. Thirty-six patients had SWF and 35 patients presented with CF. The mean time to radiologic union, amounts of postoperative coronal angulation, and incidence of malunion showed no statistical differences. Fibular fixation was more applied in the CF group (P < 0.001). Moreover, the clinical scores revealed no differences. Nonetheless, in the valgus union group, the AOFAS ankle–hindfoot score was 90.9 compared to 84.1 in the varus union group (P = 0.042) and the FFI was 9.2% compared to 20.2% in the varus union group (P = 0.017). Conclusion: Plate osteosynthesis for SWF or CF of the distal tibial metadiaphysis led to high union rates and good clinical outcomes. There was no significant difference in the radiologic and clinical results according to the presence of fracture comminution. Nonetheless, the valgus union group showed better clinical outcomes than the varus union group. Clinically, it would be preferred to avoid intraoperative varus reduction.

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