Lian Duan

Prof. Dr. Lian Duan


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 April 2022 in Atmosphere
Verified
Journal Article
Open access
PDF file
HYHan Yue
Han Yue
LDLian Duan
Lian Duan
MLMingshen Lu
Mingshen Lu
HHHongsheng Huang
Hongsheng Huang
XZXinyin Zhang
Xinyin Zhang
HLHuilin Liu
Huilin Liu
Many studies have identified the influences of PM2.5. However, very little research has addressed the spatiotemporal dependence and heterogeneity in the relationships between impact factors and PM2.5. This study firstly utilizes spatial statistics and time series analysis to investigate the spatial and temporal dependence of PM2.5 at the city level in China using a three-year (2015–2017) dataset. Then, a new local regression model, multiscale geographically weighted regression (MGWR), is introduced, based on which we measure the influence of PM2.5. A spatiotemporal lag is constructed and included in MGWR to account for spatiotemporal dependence and spatial heterogeneity simultaneously. Results of MGWR are comprehensively compared with those of ordinary least square (OLS) and geographically weighted regression (GWR). Experimental results show that PM2.5 is autocorrelated in both space and time. Compared with existing approaches, MGWR with a spatiotemporal lag (MGWRL) achieves a higher goodness-of-fit and a more significant effect on eliminating residual spatial autocorrelation. Parameter estimates from MGWR demonstrate significant spatial heterogeneity, which traditional global models fail to detect. Results also indicate the use of MGWR for generating local spatiotemporal dependence evaluations which are conditioned on various covariates rather than being simple descriptions of a pattern. This study offers a more accurate method to model geographic events.

29 January 2021 in Smart Cities
Verified
Journal Article
Open access
PDF file
Xinyue YeXinyue Ye
Xinyue Ye
LDLian Duan
Lian Duan
QPQiong Peng
Qiong Peng
Spatiotemporal prediction of crime is crucial for public safety and smart cities operation. As crime incidents are distributed sparsely across space and time, existing deep-learning methods constrained by coarse spatial scale offer only limited values in prediction of crime density. This paper proposes the use of deep inception-residual networks (DIRNet) to conduct fine-grained, theft-related crime prediction based on non-emergency service request data (311 events). Specifically, it outlines the employment of inception units comprising asymmetrical convolution layers to draw low-level spatiotemporal dependencies hidden in crime events and complaint records in the 311 dataset. Afterward, this paper details how residual units can be applied to capture high-level spatiotemporal features from low-level spatiotemporal dependencies for the final prediction. The effectiveness of the proposed DIRNet is evaluated based on theft-related crime data and 311 data in New York City from 2010 to 2015. The results confirm that the DIRNet obtains an average F1 of 71%, which is better than other prediction models.

21 March 2024 in Agronomy
Verified
Journal Article
Open access
PDF file
SLShuangshuang Lai
Shuangshuang Lai
HMHailin Ming
Hailin Ming
QHQiuyan Huang
Qiuyan Huang
ZQZhihao Qin
Zhihao Qin
LDLian Duan
Lian Duan
GHGuangping Han
Guangping Han
The efficient management of commercial orchards strongly requires accurate information on plant growing status for the implementation of necessary farming activities such as irrigation, fertilization, and pest control. Crown planar area and plant number are two very important parameters directly relating to fruit growth conditions and the final productivity of an orchard. In this study, in order to propose a novel and effective method to extract the crown planar area and number of mature and young papayas based on visible light images obtained from a DJ Phantom 4 RTK, we compared different vegetation indices (NGRDI, RGBVI, and VDVI), filter types (high- and low-pass filters), and filter convolution kernel sizes (3–51 pixels). Then, Otsu’s method was used to segment the crown planar area of the papayas, and the mean–standard deviation threshold (MSDT) method was used to identify the number of plants. Finally, the extraction accuracy of the crown planar area and number of mature and young papayas was validated. The results show that VDVI had the highest capability to separate the papayas from other ground objects. The best filter convolution kernel size was 23 pixels for the low-pass filter extraction of crown planar areas in mature and young plants. As to the plant number identification, segmentation could be set to the threshold with the highest F-score, i.e., the deviation coefficient n = 0 for single young papaya plants, n = 1 for single mature ones, and n = 1.4 for crown-connecting mature ones. Verification indicated that the average accuracy of crown planar area extraction was 93.71% for both young and mature papaya orchards and 95.54% for extracting the number of papaya plants. This set of methods can provide a reference for information extraction regarding papaya and other fruit trees with a similar crown morphology.

16 December 2025 in Sensors
Verified
Journal Article
Open access
PDF file
LZLinpeng Zhang
Linpeng Zhang
JMJi Ma
Ji Ma
YLYanhua Liu
Yanhua Liu
LDLian Duan
Lian Duan
YLYunfei Liang
Yunfei Liang
YLYanhe Lu
Yanhe Lu
In indoor environments, fusion localization methods that combine Wi-Fi fingerprinting and Pedestrian Dead Reckoning (PDR) are constrained by the high sensitivity of traditional filters, such as the Extended Kalman Filter (EKF), to initial states and by their susceptibility to nonlinear drift. This study presents a Wi-Fi/PDR fusion localization approach based on global geometric alignment optimized via a Genetic Algorithm (GA). The proposed method models the PDR trajectory as an integrated geometric entity and performs a global search for the optimal two-dimensional similarity transformation that aligns it with discrete Wi-Fi observations, thereby eliminating dependence on precise initial conditions and mitigating multipath noise. Experiments conducted in a real office environment (14 × 9 m, eight dual-band APs) with a double-L trajectory demonstrate that the proposed GA fusion achieves the lowest mean error of 0.878 m (compared to 2.890 m, 1.277 m, and 1.193 m for Wi-Fi, PDR, and EKF fusion, respectively) and an RMSE of 0.978 m. It also attains the best trajectory fidelity (DTW = 0.390 m, improving by 71.0%, 14.7%, and 27.8%) and the smallest maximum deviation (Hausdorff = 1.904 m, 52.4% lower than Wi-Fi). The cumulative error distribution shows that 90% of GA fusion errors are within 1.5 m, outperforming EKF and PDR. Additional experiments that compare the proposed GA optimizer with Levenberg–Marquardt (LM), particle swarm optimization (PSO), and Procrustes alignment, as well as tests with 30% artificial Wi-Fi outliers, further confirm the robustness of the Huber-based cost and the effectiveness of the global optimization framework. These results indicate that the proposed GA-based fusion method achieves high robustness and accuracy in the tested office-scale scenario and demonstrate its potential as a practical multi-sensor fusion approach for indoor localization.

5 October 2026 in Sustainability
Verified
Journal Article
Open access
PDF file
PSP S
P S
ZXZhigang Xu
Zhigang Xu
LDLian Duan
Lian Duan
Classroom evacuation is constrained by relatively fixed occupant positions, dense desk-and-chair arrangements, restricted aisles, and limited exits, and is jointly influenced by occupant behavior, spatial conditions, and emergency scenarios. This review proposes a four-stage framework comprising scenario and data, experiments and modeling, analysis and evaluation, and optimization and validation, and synthesizes studies on evacuation methods, evaluation indicators, scenario-specific characteristics, and optimization strategies. Existing approaches include evacuation drills and experiments, simulation software, cellular automata, social force models, and agent-based models, with increasing applications of machine learning, reinforcement learning, and virtual reality. Evaluation mainly focuses on time, movement, density and flow, paths, and exits. Fire, low-visibility conditions, earthquakes, and violent attacks exhibit distinct evacuation characteristics, while the effectiveness of exit configuration, desk-and-chair layout, organizational guidance, safety education, special-needs support, and dynamic route guidance varies across occupant groups and scenarios. Overall, research is shifting from single-factor analysis toward integrated analysis of occupants, space, and hazards. However, gaps remain in empirical data, model calibration and validation, multi-factor optimization, and continuous evacuation analysis from classrooms to building exits. Future studies should strengthen multi-scenario data support, experimental–model cross-validation, coordinated optimization, and intelligent decision-making and emergency training.