ABSTRACT This paper proposes an impulse‐based representation of earthquake ground motions for the simultaneous optimal design of viscous and hysteretic dampers in elastic–plastic structures. The method transforms ground motions into representative impulse ground motions (RIs) using an energy‐based approach. By introducing the concept of truncated ground motion, the proposed method captures the dominant portion of the input without overestimating structural responses, ensuring response bounding. A design framework is developed where dominant RIs are used instead of multiple ground motions with common performance criteria, enabling efficient optimization. A sensitivity‐based algorithm is formulated for the simultaneous optimization of viscous and hysteretic dampers, incorporating singular value decomposition, switching of objective functions, and a correction scheme to avoid nonphysical solutions. Numerical examples using a high‐rise elastic–plastic building model demonstrate that the proposed RI‐based approach achieves accurate response estimation while significantly reducing computational effort. The optimized damper distributions satisfy prescribed performance criteria across different types of ground motions, including long‐duration and pulse‐like ground motions.
ABSTRACT This paper aims to analyze requisitioned lands and buildings in Sapporo, Japan, during the early period of the postwar occupation, by the General Headquarters. Previous studies show only names of requisitioned buildings in Sapporo. However, this paper is original in that it provides a detailed architectural analysis, including buildings those that were not requisitioned, extending the study up to the point when they were derequisitioned. The authors focuses on four primary aspects: (1) Location—business districts featuring urban infrastructure and suburban areas comprising residences and former Japanese Military facilities were requisitioned; (2) Year of construction—modern buildings constructed or renovated around the preceding 15 years were targeted; (3) Structure types—reinforced concrete buildings, well‐equipped and predominantly located in urban areas, were requisitioned, whereas wooden structures were requisitioned primarily in suburban areas; (4) Sanitation and environment—buildings equipped with flush toilets and situated in sanitary environments were preferred. Although Sapporo, as non‐war‐damaged city, possessed numerous potentially requisition able buildings, the total number requisitioned was relatively small compared to other major Japanese cities. This finding indicates that city condition of Sapporo did not fully satisfy GHQ's requisition criteria. The results contribute to a deeper understanding of postwar local cities in Japan.
ABSTRACT There is increasing demand for accessibility in assembly facilities such as theaters, yet fire evacuation remains a critical challenge. People with mobility limitations must evacuate alongside other audience members, often under complex and stressful conditions. This study investigates inclusive evacuation behavior and psychological responses of wheelchair users during theater fires, focusing on three key phases: passing through doors, moving through foyers, and waiting for elevators in lobbies. Using a virtual reality environment, nondisabled participants operating wheelchairs experienced simulated evacuations within large crowds of nondisabled individuals. The results indicate that spatial configuration has both direct and indirect effects: it influences wheelchair users' movement and shapes their experience through crowd dynamics. Wider exit doors and reduced congestion improved passage, while spacious foyers enabled movement even against opposing flows. In contrast, narrowing lobby doors to reduce crowd density had limited impact on users' sense of relief while waiting for elevators. Instead, communication and operator‐controlled elevator systems played more significant roles in perceived safety. The challenges faced by wheelchair users vary by location and situation, particularly in dense crowds. These findings highlight the need for integrated spatial design and staff guidance that address both crowd movement and the psychological needs of wheelchair users.
ABSTRACT The Nameless Landscape , which is spontaneously created in daily life and often difficult for local residents to evaluate, is analyzed here from the perspective of the traveler as outsider. The purpose of this study is to clarify the value and the structure of semantic interpretation of the Nameless Landscape as perceived by foreign travelers, specifically by analyzing their observation and interpretation processes. The study reveals the inherent nature of the Nameless Landscape and illustrates the knowledge updating process triggered by observation. Finally, it proposes a structural model of semantic interpretation to represent these findings.
ABSTRACT Water‐based ceiling radiant cooling systems are increasingly adopted in Japan for thermal comfort and energy savings. However, conventional design methods relying on assumed target operative temperatures (OT) and uncooled surface temperatures often create discrepancies between expected and actual indoor environments. This complicates cooling capacity estimations and panel requirements, especially when combined with convection systems. This study proposes C‐DM, a novel design method integrating computational fluid dynamics (CFD) into the conventional ASHRAE approach. By utilizing CFD to replicate actual phenomena, C‐DM determines multiple parameters simultaneously and employs feedback control to accurately establish the radiant panels' cooling capacity needed for the target thermal environment. To evaluate its effectiveness, C‐DM was applied to redesign a real office equipped with a ceiling radiant cooling system. Results demonstrate that the radiant panels' cooling capacity can be increased by 15.26 W/m 2 without compromising indoor thermal comfort, enabling highly effective system utilization. Furthermore, while maintaining the existing ratio of radiant to convection air conditioning, the required number of panels can be reduced by 0.21 units per square meter of floor area.
