Although there are various preferences for color, the city color planning in South Korea is dominated by the government, and the city color preferences of residents are considered to a less extent. Therefore, it results in a question of how to accommodate the diversity of individual preferences. This study took Busan City as an example, using the data collected by the questionnaire survey, first through the chi-square test and nonlinear canonical correlation analysis model to analyze individual attribute factors that distinguish the diversity of city color preferences. It was found that age significantly impacted city color preference, followed by occupation, residential type, educational background, residential location, sex, and monthly income. Regarding the three elements of color, the most significant differences in city color preference were chroma and hue, with slight differences in value preference. Finally, the results were compared with city color guideline to identify the potential conflicts. The findings can provide some recommendations for bottom-up city color planning, and be applied in architectural design and urban regeneration.

Since the advent of the 21st century, with the promulgation of landscape laws and related landscape management regulations, city color, as a vital component of the urban landscape, has garnered increasing attention. In East Asia, numerous cities have embraced city color planning as a means to enhance their urban landscape and shape the distinctive features of the city. Therefore, this study focuses on exploring the characteristics of city color planning systems in East Asia by adopting qualitative analysis methods, using Tokyo, Seoul, and Beijing as case study examples. We used publications, academic research, and official documents clustered into seven domains to identify the following: government agency, introduction time, relevant laws, upper plan, tools/management, planning method, and planning contents. The results revealed that compared with Europe, city color planning in East Asia is government-led top-down planning, and there are remarkable similarities in the formulation process, planning methods, and color selection, while there are obvious deficiencies in the professionalism of the planning authorities and public participation. The results of this study provide a valuable reference for city color planning in the future, thereby enhancing the urban landscape and shaping unique city identities in East Asia.

Communities worldwide are increasingly required to support populations spanning multiple generations while maintaining social cohesion in the context of rapid demographic ageing and urban transformation. Although frameworks for age-friendly or inclusive environments have gained international traction, existing evaluation methods seldom integrate the environmental qualities necessary for all-age-friendliness with the spatial and social conditions that enable cross-generational interaction. This study addresses this gap by developing a dual-lens evaluation framework that quantifies both fundamental environmental attributes and the interaction potential embedded within community spaces. Grounded in field investigations, spatial analysis, expert consultation, and user surveys, the study establishes a hierarchical indicator system comprising nineteen prerequisite indicators and sixteen enhancement indicators across five dimensions: site accessibility, spatial integration, environmental comfort, safety and health, and participation and inclusion. To operationalize the framework, a combined Fuzzy Analytic Hierarchy Process and multi-objective optimization model was employed, enabling the representation of interdependencies between essential conditions and value-enhancing features. Application of the framework to 24 community cases in Shanghai and Florence reveals both shared structural patterns and distinctive cultural influences: Shanghai demonstrates strengths in walkability and health-supportive infrastructure, whereas Florence excels in natural contact and environmentally integrated spatial typologies. The findings underscore the necessity of balanced environmental performance for achieving high-quality, all-age-friendly community spaces with strong cross-generational engagement potential. The proposed framework provides a replicable and analytically rigorous tool for environmental and social impact assessment, offering guidance for planners, policymakers, and designers seeking to promote inclusive, resilient, and socially cohesive community environments.