The transparency and shape of tree crowns in urban areas play a critical role in applications such as solar energy potential estimation, urban microclimate modeling, and urban landscape planning and architecture. Data-driven approaches model tree crown attributes using point cloud data, but high-density point clouds are cost-prohibitive. To improve modeling capabilities of widely available medium-resolution aerial LiDAR, Vishnu's dissertation explores techniques for urban tree modeling, including accounting for seasonal variations in crown transparency, using deep learning to select the crown shape of a tree based on its point cloud, and comparing the performance of algorithms for tree crown delineation. Part of this research focuses on demonstrating the use of a Convolutional Neural Network (CNN) model and 3D models generated with Structure from Motion (SfM) for the realistic modeling of deciduous non-overlapping trees over large spatial extents from discrete return ALS data.

Vivek Nanda, V. M., Baran, P., & Tateosian, L. (accepted for publication, 2023).  Classification of tree forms in aerial LiDAR point clouds using CNN for 3D tree modelling. International Journal of Remote Sensing.

Vivek Nanda, V. M. (2023). Estimating and Modeling Structural Characteristics of Trees within Aerial LiDAR Data (Unpublished doctoral dissertation). NCSU, Raleigh. (PhD in Geospatial Analytics) https://repository.lib.ncsu.edu/handle/1840.20/40818.

Vivek Nanda, V. M., Tateosian, L., and Baran, P. (2020). GIS-Based Estimation of Seasonal Solar Energy Potential for Parking Lots and Roads, IEEE Green Technologies Conference Proceedings 2020 & IEEE Xplore. 

Saeed’s research focused on addressing equity and environmental justice in physical activity and active transportation research. He investigated micro-scale environmental features in streets that promote walkability and developed an Augmented Reality participatory tool to engage citizens, particularly residents of under-resourced communities, in the urban design and planning process. 

Ahmadi Oloonabadi, S., & Baran, P., (2023). Augmented Reality Participatory Platform: A Novel Digital Participatory Planning Tool to Engage Under-resourced Communities in Improving Neighborhood Walkability. Cities, 141, October 2023, 104441. https://doi.org/10.1016/j.cities.2023.104441

Ahmadi, S. (2021). A Novel Mobile Augmented Reality Participatory Platform to Engage Under-Resourced Communities in Improving Neighborhood Walkability (Unpublished doctoral dissertation). NCSU, Raleigh. (PhD in Design) https://repository.lib.ncsu.edu/handle/1840.20/40175

Ahmadi, S., & Baran, P. (2018). The just street: An augmented reality tool to empower disadvantaged communities in designing more walkable streets. Paper presented at the EDRA 49 Conference: Social Equity by Design: Designing Connections through Community. Oklahoma City, OK: June 6-9, 2018.

In his dissertation, Payam leveraged Geospatial computation, visualization and user interaction technologies to develop methodologies for enhancing research and design of environments. These methodologies aim to facilitate more efficient and accurate analysis of landscape spatial and experiential (e.g., aesthetic, restorative qualities) characteristics, and enable intuitive interaction and immersive visualization of design phenomena across spatial and temporal scales. The first methodology combines automated viewscape modeling­–geospatial analysis of visible structure and patterns– with human subjective evaluations to quantify, model, and map landscape characteristics and experience of landscapes. The second methodology focuses on real-time coupling of 3D modeling and rendering, geospatial analysis, and tangible interaction allowing users to design environments using their hands, and in real-time, receive maps and numeric feedbacks of spatial analysis, and see 3D visualizations rendered on a display or immersive head mounted displays. The methodologies and software created as part of this dissertation can be used not only in environmental design and research but also for teaching and game development. While the presented case-studies are focused on site scale urban environments, solutions can be transferred to other contexts and scales. 

Tabrizian, P., Petrasova, A., Baran, P. K., Vukomanovic, J., Mitasova, H., & Meentemeyer, R., (2020). High Resolution Viewscape Modeling Evaluated Through Immersive Virtual Environments. International Journal of Geo-Information, special issue GIS-Based Analysis for Quality of Life and Environmental Monitoring. 9, 445; doi:10.3390/ijgi9070445.

Tabrizian, P., Baran, P. K., Van Berkel, D., Mitasova, H., & Meentemeyer, R. (2020). Modeling restorative potential of urban environments by coupling viewscape analysis of lidar data with experiments in immersive virtual environments. Landscape and Urban Planning. 195 (March 2020), 103704. https://doi.org/10.1016/j.landurbplan.2019.103704

Tabrizian. P. (2018). Integrating geospatial computation, virtual reality and tangible interaction to improve landscape design and research (Unpublished doctoral dissertation). NCSU, Raleigh. (PhD in Design and PhD in Geospatial Analytics). https://repository.lib.ncsu.edu/handle/1840.20/35668

Yujia's research explored how urban park design characteristics are related to seniors’ walking within a park. The study sites included two neighborhood parks located in Beijing, China. Mixed methods approach, comprised of correlational research and interviews, was utilized in answering the research questions. In the study, park pathways were conceptualized at overall park and pathway segments levels. For correlational research, independent variables comprised four dimensions of pathway characteristics: pathway physical attributes, pathway configurational attributes, spatial characteristics of pathway surrounding, and visual characteristics of pathway surrounding. Aggregate number of senior users on each pathway observed in 24 rounds of observations were the dependent variables. In the interviews, senior participants were invited to talk about their perceptions about walking in the parks, as wells as pathway characteristics they like and dislike. Overall, the study results indicate that pathways that have even pavement, have benches and light fixtures, are long and have a width between 3-3.9 meters, are connected to other pathway segments, have relatively high configurational accessibility, and are closer to park entrances are heavily used by seniors. 

Zhai, Y. & Baran, P. K. (2017). Urban park pathway design characteristics and senior walking behavior. Urban Forestry and Urban Greening, 21: 60-73. 

Zhai, Y. & Baran, P. K. (2016). Do configurational attributes matter in context of urban parks? Park pathway configurational attributes and senior walking. Landscape and Urban Planning. 148: 188-202. 

Zhai, Y. (2014). Urban park pathway design characteristics and seniors' walking behavior (Unpublished doctoral dissertation). NCSU, Raleigh. https://repository.lib.ncsu.edu/handle/1840.16/10306

As shrinking cities in the US have moved away from the fundamental assumption that a city needs to grow and city managers begin to close sparsely populated neighborhoods, something unexpected is occurring: Remaining residents are resisting the move. Why does this inertia, or resistance to change, continue even during exceptional urban decay? This study claims that a potentially significant, yet little investigated factor in understanding the form and growth of cities is structural inertia: defined as the tendency of an urban area to resist change due to its existing physical, economic, social, and cultural fabric.

The primary purpose of this study was to understand how existing patterns of buildings, plots, blocks, and streets affect structural inertia in first-ring suburban neighborhoods. In order to understand structural inertia, measuring change or persistence in the patterns of space and the built environment over time were of primary concern. Research for this study employed a multiple case study longitudinal approach. The study utilized Conzenian morphology, space syntax, and a place attachment survey instrument in a 90-year time-series case study of four inner-ring neighborhoods in Raleigh and Charlotte, NC. Three morphological and three space syntax independent variables were compared to the dependent variable of change—in building inventory and land use change. Both in-case and cross case examinations were made of the relationships between the predictor and outcome variables in four separate time intervals. This research developed a theoretical and empirical basis upon which practical design and policy tools can be generated to predict and design for structural inertia: particularly in the growth and decay of first-ring suburban neighborhoods. 

Hallowell, G. & Baran, P. (2020). Neighborhood dynamics and long-term change. Geographical Analysis, special issue: Spatial Perspectives on Neighborhood Effects and Neighborhood Dynamics. https://doi.org/10.1111/gean.12240

Hallowell, G. D. & Baran, P. K. (2013). Suburban change: A time series approach to measuring form and spatial configuration. Journal of Space Syntax (JOSS:) Special Issue on Urban Challenges. 4(1): 74-91.

Hallowell, G. (2013). Understanding structural inertia: Examining suburban morphology and patterns of Persistence and change (Unpublished doctoral dissertation). NCSU, Raleigh. https://repository.lib.ncsu.edu/handle/1840.16/8414

Research has recognized that urban environment can facilitate/limit one’s orientation, depending on the structure and characteristics of the physical elements of the city. In this regard, Lynch’s concept of legibility has been fundamental in the urban design, planning, architecture, and environmental design fields for a few decades. Lynch argued that a strong legible city could facilitate humans’ orientation in the city. However, urban design research has also criticized Lynch’s work for ignoring the relational characteristics between physical elements of the urban environment. Recent research has suggested that Space Syntax methodology could address the limitations of Lynch’s approach to urban spatial cognition. This study focused on exploring: a) the relationships between human cognitive representations and spatial configuration of the urban environment, and b) the effects that different spatial configurations have on legibility of the environment. To address the research questions, two research studies, correlational and experimental, were performed. Study areas included two neighborhoods, one relatively intelligible and the other less so, in Changsha, China. The Space Syntax approach was utilized to measure spatial configuration of the neighborhoods, while sketch maps, recognition tests, and interviews were used to measure individuals’ cognitive representations and their perceived legibility of the environment. Overall, the findings suggest that the more intelligible an area is, measured by Space Syntax as objective value of spatial configuration, the more legibly it is reflected in a human’s spatial cognition.

Long, Y, & Baran, P. K. (2012). Does intelligibility affect place legibility? Understanding the relationship between objective and subjective evaluations of the urban environment. Environment and Behavior, 44(5), 616-640. 

Long, Y. (2007). The relationships between objective and subjective evaluations of the urban environment: Space syntax, cognitive maps, and urban legibility (Unpublished doctoral dissertation). NCSU, Raleigh. https://repository.lib.ncsu.edu/handle/1840.16/4411