Even in an era where 8-meter class telescopes are common, small telescopes are considered very valuable research facilities since they are available for rapid follow-up or long term monitoring observations. To maximize the usefulness of small telescopes in Korea, we established the SomangNet, a network of 0.4{1.0 m class optical telescopes operated by Korean institutions, in 2020. Here, we give an overview of the project, describing the current participating telescopes, its scientic scope and operation mode, and the prospects for future activities. SomangNet currently includes 10 telescopes that are located in Australia, USA, and Chile as well as in Korea. The operation of many of these telescopes currently relies on operators, and we plan to upgrade them for remote or robotic operation. The latest SomangNet science projects include monitoring and follow-up observational studies of galaxies, supernovae, active galactic nuclei, symbiotic stars, solar system objects, neutrino/gravitational-wave sources, and exoplanets.

The object of this container is to store uranium precipitated in Mo-99 production process for long term. It will be used in the Gijang reactor. Uranium precipitates is stored in a container such as a form of filter cake. This container will be stored in the underground concrete storage for about 50 years when considering a storage facility life and safety. It is required high degree of structure integrity when considering decay heat from radioactive precipitated, external impact and etc, because it has to store radioactive materials for long term. In this study, thermal, structural and impact analysis about a container inserted 6 canisters was carried out. In the case of this thermal analysis, the object is to investigate the effect decay heat of uranium precipitate on the structure integrity of a container. The structural analysis was carried out to evaluate a structure integrity of the bottommost portion container among the 9 loaded containers. Finally, the impact analysis was carried out to evaluate the structure integrity of a container when that is dropped from maximum height of 5m during transport. As a result of this study, the structural integrity of this container is satisfactory about thermal, structural and impact.

RTG (Radioisotope Thermoelectric Generator) is a power generation system producing electricity by converting the thermal energy gained from shielding radioisotope. RTG generates power without being charged from outside and as it utilizes radioisotope, RTG mainly serves as an energy source operated for a specific purpose in environment hardly accessible by human. Its design structures vary according to its purpose of operation, thermal source of operation and environment of operation. Since RTG is a power generation system, it should have the highest power efficiency with limited heat source. In this study, heat transfer analysis was implemented to investigate diverse design factors influencing the insulation system of RTG for aerospace use. Design factors considered in this study were silver coating, number of radiation shields inside vacuum insulation and supporter material. As a result, it was found that, depending upon design factors, insulation efficiency increased by 9.3% and finally insulation efficiency of RTG v2.0 was estimated at 84.3%.

This transport cask for radioactive materials will be used in the Gijang reactor. It will transport the Ir-192 10,000 Ci or I-131 80 Ci. In this case, the safety evaluation, such as protection of leakage of radioactive material, and radiation shield should be carried out before it is used in the research reactor. The safety regulation requires various tests, such as water spray, free drop, penetration, and water immersion. But this paper considers only the regulations related with thermal-stress and drop impact under the normal conditions because it will be used only in the research reactor building. In this paper, coupled numerical analysis was performed using finite element simulation to investigate the effect of position of tungsten and lead to enhance the safety of transport cask. As a result of simulation, it was verified that the Tungsten-Lead structure is the most durable among the cases considered in the study with a viewpoint of thermal-stress and drop impact.