The freeway service patrol problem involves patrol routing design and fleet allocation on freeways that would help transportation agency decision-makers when developing a freeway service patrols program and/or altering existing route coverage and fleet allocation. Based on the actual patrol process, our model presents an overlapping patrol model and addresses patrol routing design and fleet allocation in a single integrated model. The objective is to minimize the overall average incident response time. Two strategies—overlapping patrol and non-overlapping patrol—are compared in our paper. Matrix encoding is applied in the genetic algorithm (GA), and to maintain population diversity and avoid premature convergence, a niche strategy is incorporated into the traditional genetic algorithm. Meanwhile, an elitist strategy is employed to speed up the convergence. Using numerical experiments conducted based on data from the Sioux Falls network, we clearly show that: overlapping patrol strategy is superior to non-overlapping patrol strategy; the GA outperforms the simulated annealing (SA) algorithm; and the computational efficiency can be improved when LINGO software is used to solve the problem of fleet allocation.
Introduction
This randomized, double-blind trial aimed to test effect of a Chinese herbal medicine, Qinggongshoutao (QGST) pill, on the cognition and progression of amnestic mild cognitive impairment (aMCI).
Methods
Patients with aMCI were randomly assigned to receive QGST,
Ginkgo biloba
extract, or placebo for 52 weeks. The primary outcome measures were progression to possible or probable Alzheimer's disease (AD) and change in Alzheimer's Disease Assessment Scale–cognitive subscale scores; secondary outcome measures included assessments for cognition and function.
Results
Total 350 patients were enrolled, possible or probable AD developed in 10. There were significant differences in the probability of progression to AD in the QGST group (1.15%) compared with placebo group (10%). There was significant difference in Alzheimer's Disease Assessment Scale–cognitive subscale scores in favor of QGST over the placebo group. Secondary outcome measure (Mini-Mental State Examination) also showed benefit in QGST at end point.
Discussion
In patients with aMCI, QGST showed lower AD progression rate than placebo at 8.85%, and may have benefit on global cognition.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.