A systematic procedure is presented for calibrating and validating a microscopic model of safety performance. The context in the model application is the potential for rear-end crashes at signalized intersections. VISSIM v.4.3 provides the simulation platform for estimating the safety performance for individual vehicles and has been calibrated and validated using separate samples of observed vehicle tracking data extracted from the FHWA/NGSIM program. The calibration exercise involves four sequential steps: (1) heuristic selection of initial model inputs, (2) statistical screening using a Plackett-Burnman design, (3) fractional factorial analysis relating inputs to safety performance, and (4) genetic algorithm procedure for obtaining best estimate input values. Three measures of safety performance were considered: crash potential index, number of vehicles in conflict and total conflict duration per vehicle. Model consistency was assessed by comparing simulated and observed safety performance based on a separate validation sample of vehicle tracking data. The suggested procedure was found to effectively estimate model input parameters that closely matched safety performance measures in the observed validation data. This procedure yields an objective and efficient means for simulation model calibration applied for estimating safety performance at signalized intersections.
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http://dx.doi.org/10.1016/j.aap.2008.01.003 | DOI Listing |
Adv Mater
January 2025
Institute of Thin Film Physics and Applications, Shenzhen Key Laboratory of Advanced Thin Films and Applications, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
Anisotropic carrier transport and deep-level defect of antimony selenosulfide (Sb(S,Se)) absorber are two vital auses restraining the photovoltaic performance of this emerging thin-film solar cell. Herein, chelate engineering is proposed to prepare high-quality Sb(S,Se) film based on hydrothermal deposition approach, which realizes desirable carrier transport and passivated defects by using tetrahedral PO ion in dibasic sodium phosphate (NaHPO, DSP). The PO Lewis structure, on one hand in the form of [(SbO)(PO)] chelate, can adsorb on the polar planes of cadmium sulfide (CdS) layer, promoting the heterogeneous nucleation, and on the other hand, the tetrahedral PO inhibits horizontal growth of (SbS(e)) ribbons due to size effects, thus achieving desirable [hk1] orientation.
View Article and Find Full Text PDFMinim Invasive Ther Allied Technol
January 2025
Department of Gastroenterology, Zhongda Hospital Southeast University, Nanjing, China.
Background: The aim of this study was to verify the safety and efficacy of endoscopic resection (ER) for gastric gastrointestinal stromal tumors (GISTs).
Methods: Among a consecutive series of resections for gastric GISTs performed in a single center, the outcomes of patients who had ER were compared to standard surgical resection (SR).
Results: In the cohort, 329 consecutive primary localized gastric GISTs patients (, ER/SR = 251/78) were enrolled.
J Alzheimers Dis
January 2025
Department of Neurology and the Franke Barrow Global Neuroscience Education Center, Barrow Neurological Institute, Phoenix, AZ, USA.
Background: The aim of this study was to examine the potential added value of including neuropsychiatric symptoms (NPS) in machine learning (ML) models, along with demographic features and Alzheimer's disease (AD) biomarkers, to predict decline or non-decline in global and domain-specific cognitive scores among community-dwelling older adults.
Objective: To evaluate the impact of adding NPS to AD biomarkers on ML model accuracy in predicting cognitive decline among older adults.
Methods: The study was conducted in the setting of the Mayo Clinic Study of Aging, including participants aged ≥ 50 years with information on demographics (i.
Cureus
December 2024
School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, IND.
Aim Traditional Ayurvedic herbo-mineral medicines have proven their potential in managing COVID-19. Cell-based assays of the Svarnvir-IV tablet demonstrated the virucidal activity against SARS-CoV-2 and its therapeutic action, along with safety in cytotoxicity, has been proved. In the present study, in vivo, safety profile and compositional analysis of the Svarnvir-IV tablet were performed.
View Article and Find Full Text PDFCureus
December 2024
Radiology, Fernandez Hospital, Hyderabad, IND.
Urological malignancies during pregnancy are exceedingly rare, with bladder cancer posing significant diagnostic and management challenges. This study describes a 28-year-old pregnant woman diagnosed with non-invasive papillary urothelial carcinoma, presenting with painless hematuria at 22 weeks of gestation. The diagnostic process included ultrasound and MRI, both of which confirmed a solitary polypoidal lesion.
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