The modeling process is essential for conducting simulations. Order estimations play a crucial role in this modeling process. The first part of this series presents the mindset and key considerations for modeling, using examples from circuit and electromagnet design. In the second part, to help readers understand the (hidden) operations involved when using existing code, the explanation focuses on solving the eigenvalue problem in the analysis of electromagnetic fields within a high-frequency air-core cavity. While the weighted residual method is frequently used in many solution methods, there are various types of this approach. The finite element method is one such example. A comparison is made using examples where several solution methods have been simplified to one dimension.

Radioisotopes (RIs) produced by accelerator technologies are becoming increasingly important not only in nuclear medicine diagnostics, but also in cancer therapy. In particular, theranostics, which integrates diagnostics and therapy, is attracting global attention as a next-generation form of precision medicine. This article discusses the medical value of accelerator technologies from the perspective of radiopharmaceutical development, manufacturing, quality assurance, supply, and clinical implementation. RIs produced by accelerators become true medical value only when they are connected with radiochemistry, formulation, Good Manufacturing Practice (GMP)-based quality control, half-life-based logistics, clinical site readiness, and patient selection. Through PDRadiophama Inc. and the PeptiDream Inc.’s efforts in theranostics, macrocyclic peptide-based Drug Delivery System (DDS), Phase 0 studies, and domestic RI supply, this article highlights the importance of the value chain “from accelerators to the bedside.” At the end of this value chain, there is always a patient.

The history of accelerators is long, and the development of high-power microwave generators such as magnetrons and klystrons in the 1940s accelerated the development and practical application of linacs, which linearly accelerate electrons using high-frequency power. Accelerator technology is a comprehensive technology that requires knowledge and experience across a wide range of academic fields. Its application fields are diverse, but they are mainly niche fields and are not generally well known. This paper examines the future market trends, technological trends, and challenges of accelerator-related businesses, focusing on the following three businesses: medical radiation therapy equipment as one of the few successful examples, large container inspection systems which are in a growth phase with the expansion of global trade, and social infrastructure inspection systems which are essential for public safety and maintaining the functionality of local communities, but are still in their nascent stages. What can be said in common is that growth businesses have a broad global market, require good cooperation among industry, government, academia, and users, and require technological capabilities and strategies to engage with global standards. It seems that social infrastructure inspection systems, which will become important in the future, need to be developed within a national framework.

For the sustainable growth of the accelerator science field, educational programs for the next generation are essential. To this end, we launched a program called “AxeLatoon.” The program started in 2020, and activities such as constructing small-scale cyclotron accelerators are being conducted at several KOSENs (National Institutes of Technology). This paper reports on the 2025 exchange meeting and summarizes its outcomes. It also highlights the educational impact of hands-on accelerator activities in fostering the next generation of scientists and engineers.