3D city models have become common geospatial data assets for cities that can be utilized in numerous fields, in tasks related to planning, visualization, and decision-making among others. We present a study of 3D city modeling focusing on the six largest cities in Finland. The study portrays a contradiction between the realized 3D city modeling projects and the expectations towards them: models do not appear to reach the broad applicability envisioned. In order to deal with contradiction and to support the development of future 3D city models, characteristics of different operational cultures in 3D city modeling are presented, and a concept for harmonizing the 3D city modeling is suggested.
3D city models and their browser-based applications have become an increasingly applied tool in the cities. One of their applications is the analysis views and visibility, applicable to property valuation and evaluation of urban green infrastructure. We present a near real-time semantic view analysis relying on a 3D city model, implemented in a web browser. The analysis is tested in two alternative use cases: property valuation and evaluation of the urban green infrastructure. The results describe the elements visible from a given location, and can also be applied to object type specific analysis, such as green view index estimation, with the main benefit being the freedom of choosing the point-of-view obtained with the 3D model. Several promising development directions can be identified based on the current implementation and experiment results, including the integration of the semantic view analysis with virtual reality immersive visualization or 3D city model application development platforms.
The Internet has become a major dissemination and sharing platform for 3D content. The utilization of 3D measurement methods can drastically increase the production efficiency of 3D content in an increasing number of use cases where 3D documentation of real-life objects or environments is required. We demonstrated a developed, highly automated and integrated content creation process of providing reality-based photorealistic 3D models for the web. Close-range photogrammetry, terrestrial laser scanning (TLS) and their combination are compared using available state-of-the-art tools in a real-life project setting with real-life limitations. Integrating photogrammetry and TLS is a good compromise for both geometric and texture quality. Compared to approaches using only photogrammetry or TLS, it is slower and more resource-heavy but combines complementary advantages of each method, such as direct scale determination from TLS or superior image quality typically used in photogrammetry. The integration is not only beneficial, but clearly productionally possible using available state-of-the-art tools that have become increasingly available also for non-expert users. Despite the high degree of automation, some manual editing steps are still required in practice to achieve satisfactory results in terms of adequate visual quality. This is mainly due to the current limitations of WebGL technology.
The importance of ensuring the adequacy of urban ecosystem services and green infrastructure has been widely highlighted in multidisciplinary research. Meanwhile, the consolidation of cities has been a dominant trend in urban development and has led to the development and implementation of the green factor tool in cities such as Berlin, Melbourne, and Helsinki. In this study, elements of the green factor tool were monitored with laser-scanned and photogrammetrically derived point cloud datasets encompassing a yard in Espoo, Finland. The results show that with the support of 3D point clouds, it is possible to support the monitoring of the local green infrastructure, including elements of smaller size in green areas and yards. However, point clouds generated by distinct means have differing abilities in conveying information on green elements, and canopy covers, for example, might hinder these abilities. Additionally, some green factor elements are more promising for 3D measurement-based monitoring than others, such as those with clear geometrical form. The results encourage the involvement of 3D measuring technologies for monitoring local urban green infrastructure (UGI), also of small scale.
Roadside vegetation can affect the performance of installed road lighting. We demonstrate a workflow in which a car-mounted measurement system is used to assess the light-obstructing effect of roadside vegetation. The mobile mapping system (MMS) includes a panoramic camera system, laser scanner, inertial measurement unit, and satellite positioning system. The workflow and the measurement system were applied to a road section of Munkkiniemenranta, Helsinki, Finland, in 2015 and 2019. The relative luminance distribution on a road surface and the obstructing vegetation were measured before and after roadside vegetation pruning applying a luminance-calibrated mobile mapping system. The difference between the two measurements is presented, and the opportunities provided by the mobile 3D luminance measurement system are discussed.
Open Science (OS) and Research has reached mixed maturity levels in Finland. The meaning of the national project in the ecosystem of Finnish universities of applied sciences (UAS) is to enhance and elaborate OS and Open Education (OE) activities. Future actions were defined based on a survey and interviews carried out in the Finnish UAS sector during 2018 and 2019. The aim of both data collections was to evaluate the current status and attitudes towards open Research, Development, and Innovation (RDI) among staff members. Another purpose was to define the need for internal support services concerning open RDI and OE and to identify knowledge gaps. The results revealed several gaps in understanding OS and OE initiatives. Real-life actions were mostly vague, and the respondents experienced the need for support. On the other hand, the attitudes towards open RDI were positive, and the issue aroused questions and reflections. This study revealed gaps in knowledge and actions in Finnish UAS sectors. These results have been the basis of development actions such as joint workshops, educational webinars, and common instructions. The future plan includes the establishment of an experts' network for supporting open RDI and Education.