Overcoming Spatial Constraints in VR:A Survey of Redirected Walking Techniques

As the virtual reality(VR)technology strives to provide immersive and natural user experiences,the challenge of aligning vast virtual environments with limited physical spaces remains significant.This survey comprehensively explores the advancements in redirected walking(RDW)techniques aimed at overcoming spatial constraints in VR.RDW addresses this by subtly manipulating users’physical movements to allow for seamless navigation within constrained areas.The survey delves into gain perception mechanisms,detailing how slight discrepancies between virtual and real-world movements can be utilized without user awareness,thus extending the effective navigable space.Various RDW control algorithms for gain-based RDW are analyzed,highlighting their implementation and effectiveness in maintaining immersion and minimizing perceptual disturbances.Furthermore,novel methods extending beyond traditional gain-based techniques are discussed,showcasing innovative approaches that further refine VR interactions.The practical implications of RDW in enhancing safety and reducing physical collisions in VR environments are underscored,alongside its potential to improve user experience by aligning virtual exploration more closely with natural human behavior patterns.Through a thorough review of existing literature and recent advancements,this survey provides a systematic understanding for researchers,developers,and industry professionals.It underscores the importance of RDW in the future of VR,emphasizing RDW's role in making VR more accessible and practical across various applications,from education and training to therapy and entertainment.The paper concludes with a forward-looking perspective on the continued evolution and potential of RDW in revolutionizing virtual reality experiences.

EmotionMap:Visual Analysis of Video Emotional Content on a Map

Emotion plays a crucial role in gratifying users’needs during their experience of movies and TV series,and may be underutilized as a framework for exploring video content and analysis.In this paper,we present EmotionMap,a novel way of presenting emotion for daily users in 2D geography,fusing spatio-temporal information with emotional data.The interface is composed of novel visualization elements interconnected to facilitate video content exploration,understanding,and searching.EmotionMap allows understanding of the overall emotion at a glance while also giving a rapid understanding of the details.Firstly,we develop EmotionDisc which is an effective tool for collecting audiences’emotion based on emotion representation models.We collect audience and character emotional data,and then integrate the metaphor of a map to visualize video content and emotion in a hierarchical structure.EmotionMap combines sketch interaction,providing a natural approach for users’active exploration.The novelty and the effectiveness of EmotionMap have been demonstrated by the user study and experts’feedback.

Impact Assessments for Urban World Heritage:European Experiences under Scrutiny

In the context of the broadening understanding of urban heritage,including the 2011 UNESCO Recom­mendation on the Historic Urban Landscape and related United Nations agendas such as the 2030 Sustainable Devel­opment Goals and the New Urban Agenda,this article questions the relevance of limited-focused impact assessments as a tool for the holistic management of complex urban sites in the 21st century.The article identifies pitfalls in the use of such assessments,illustrating this principally with two cases in which retrospective assessments were under­taken post-inscription in an attempt to address conflicting interests:the visual impact study for Dresden Elbe Valley,inscribed on the World Heritage List in 2004 and delisted in 2009;and the three impact assessments for Liverpool Maritime Mercantile World Heritage Site,also inscribed in 2004,and placed on the List of World Heritage in Danger continuously since 2012.The article identifies critical missing elements that are inherent in discrete assessments,and provides indicators for practical tools with relevant applicability.

Repositioning Urban Heritage-Setting the Scene

International conventions,charters and recommendations tend to follow trends and are generally reactive to contemporary circumstances;the debates on urban heritage are no exception.These texts need to be read in the perspective of socio-economic and environmental considerations of their time together with their inter-dependence on other disciplines.The dramatic changes to our urban conurbations have included environmental degradation,the complexities of migrations and socio-economic transformations.Addressing these major concerns in managing urban heritage highlights the necessity for cross-disciplinarity in research and the need for adopting a more integrative attitude in the planning processes.Applying the General System Theory by the biologist Ludwig von Bertalanffy brings a systematic,holistic methodology from the realms of modern science into extending the historic centre and the city with a territorial approach of the metropolis allowing for sustainable and resilient rural and urban linkages.This article brings together seven contributions on issues affecting the Recommendation on the Historic Urban Landscape The potential of the digital revolution is in the capacity of recognizing the speed and rapidity of change,and the mega-data available as affecting our lives and environment together with the role of history,tradition and continuity in linking the past to the future.