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"This study proposes a method of optimizing the dry storage design for nuclear-spent fuel from the G.A. Siwabessy research reactor at National Nuclear Energy Agency of Indonesia (BATAN). After several years in a spent fuel pool storage (wet storage), nuclear spent fuel is often moved to dry storage. Some advantages of dry storage compared with wet storage are that there is no generation of liquid waste, no need for a complex and expensive purification system, less corrosion concerns and that dry storage is easier to transport if in the future the storage needs to be sent to the another repository or to the final disposal. In both wet and dry storage, the decay heat of spent fuel must be cooled to a safe temperature to prevent cracking of the spent fuel cladding from where hazardous radioactive nuclides could be released and harm humans and the environment. Three optimization scenarios including the thermal safety single-objective, the economic single-objective and the multi-objective optimizations are obtained. The optimum values of temperature and cost for three optimization scenarios are 317.8K (44.7°C) and 11638.1 US$ for the optimized single-objective thermal safety method, 337.1K (64.0°C) and 6345.2 US$ for the optimized single-objective cost method and 325.1K (52.0°C) and 8037.4 US$ for the optimized multi-objective method, respectively."

"An unmanned surface vehicle (USV) is operated on the water surface for specific purposes. USV can be used in waters that cannot be entered by crewed boats, such as environments with high levels of threat or that are contaminated by nuclear, biological, or chemical waste. USVs can also be used for surveys in shallow waters, escorting military weapons, collecting environmental data, and coordinating with other underwater vehicles such as automated underwater vehicles. This study designs and develops simple USV rockets for maneuvering on the water surface. First, a simple USV system is designed. Next, mechanical and electronic components are selected, and the control program is implemented using the Arduino Mega 2560 microcontroller. Finally, the USV motion kinematics are analyzed, rocket thrust force is tested, and torque generated by the electric ducted fan (EDF) motor is measured. Ultimately, a rocket system with weight of 3920 g and length, width, and height of 720 mm, 500 mm, and 420 mm, respectively, is developed. The USV rocket is driven by an EDF motor with voltage and current of 1600 kV and 160 A, respectively, an electronic speed control, 6X Turnigy FHSS remote control, and two 18.5 V Li-Po 5500 mAh batteries as a power source. The USV has a maximum thrust of 40.7 N with torque of 1.41 Nm. Kinematics parameters such as angular acceleration and linear acceleration were also determined."

"The early twenty-first century has witnessed a rising number of global crises. These include climate change, widening income inequality, military and nuclear tensions between the major powers, repeated outbreaks of global pandemics, and an ongoing democratic recession. In particular, the deepening democratic recession has afflicted ostensibly both mature and newer democracies – contradicting theories of political development. In many countries, the political alliance between ethno- and religious nationalists has reignited assaults against democratic institutions, processes, and norms. This comparative country-case study, principally of Malaysia and the United States of America (US), explores the alliance between ethno- and religious nationalists by examining the forces and factors that have contributed to this combustible dynamic within the context of unsettled national questions, contested constitutional orders, and foundational national visions. Also examined are the narratives of fear, victimhood and privilege that have galvanised religious and ‘sons of the soil’ ethno-nationalists in resisting the building of inclusive multiracial democracies."