This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combin...This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combined applications of the space-time expanded network(STEN) and the conventional network equilibrium modeling techniques,a multi-class,multi-mode and multi-criteria traffic network equilibrium model is developed.Travelers of different classes have distinctive value of times(VOTs),and travelers from the same class perceive their travel disutility or generalized costs on a route according to different weights of travel time and travel costs.Moreover,the symmetric cost function model is extended to deal with the interactions between buses and private cars.It is found that there exists a uniform(anonymous) link toll pattern which can drive a multi-class,multi-mode and multi-criteria user equilibrium flow pattern to a system optimum when the system's objective function is measured in terms of money.It is also found that the marginal cost pricing models with a symmetric travel cost function do not reflect the interactions between traffic flows of different road sections,and the obtained congestion pricing toll is smaller than the real value.展开更多
AIM To estimate annual direct and indirect costs for patients diagnosed with irritable bowel syndrome(IBS) and subtypes.METHODS Patients completed a standardized questionnaire concerning usage of healthcare resources,...AIM To estimate annual direct and indirect costs for patients diagnosed with irritable bowel syndrome(IBS) and subtypes.METHODS Patients completed a standardized questionnaire concerning usage of healthcare resources, travel costs, meals, and productivity loss of patients when seeking treatment for IBS. Total annual costs per patient were calculated as the sum of direct(including medical and nonmedical) and indirect costs. Total annual costs per patient among various IBS subtypes were compared. Analysis of variance and bootstrapped independent sample t-tests were performed to determine differences between groups after controlling for IBS subtypes.RESULTS A total of 105 IBS patients(64.80% female), mean age of 57.12 years ± 10.31 years), mean disease duration of 4.31 years ± 5.40 years, were included. Total annual costs per patient were estimated as CNy18262.84(USD2933.08). Inpatient and outpatient healthcare use were major cost drivers, accounting for 46.41%and 23.36% of total annual costs, respectively. Productivity loss accounted for 25.32% of total annual costs. The proportions of direct and indirect costs were similarto published studies in other countries. Nationally, the total costs of managing IBS would amount to CNy123.83 billion(USD1.99 billion). Among the IBS subtypes, total annual costs per patient of IBS-M was highest at CNy18891.18(USD3034). Furthermore, there was significant difference in productivity loss among IBS subtypes(P = 0.031).CONCLUSION IBS imposes a huge economic burden on patients and healthcare systems, which could account for 3.3% of the total healthcare budget for the entire Chinese nation. More than two-thirds of total annual costs of IBS consist of inpatient and outpatient healthcare use. Among the subtypes, IBS-M patients appear to have the greatest economic burden but require further confirmation.展开更多
基金The National High Technology Research and Development Program of China (863 Program) (No. 2007AA11Z202)the National Key Technology R & D Program of China during the 11th Five-Year Plan Period(No. 2006BAJ18B03)the Fundamental Research Funds for the Central Universities (No. DUT10RC(3) 112)
文摘This paper considers the problem of time varying congestion pricing to determine optimal time-varying tolls at peak periods for a queuing network with the interactions between buses and private cars.Through the combined applications of the space-time expanded network(STEN) and the conventional network equilibrium modeling techniques,a multi-class,multi-mode and multi-criteria traffic network equilibrium model is developed.Travelers of different classes have distinctive value of times(VOTs),and travelers from the same class perceive their travel disutility or generalized costs on a route according to different weights of travel time and travel costs.Moreover,the symmetric cost function model is extended to deal with the interactions between buses and private cars.It is found that there exists a uniform(anonymous) link toll pattern which can drive a multi-class,multi-mode and multi-criteria user equilibrium flow pattern to a system optimum when the system's objective function is measured in terms of money.It is also found that the marginal cost pricing models with a symmetric travel cost function do not reflect the interactions between traffic flows of different road sections,and the obtained congestion pricing toll is smaller than the real value.
文摘AIM To estimate annual direct and indirect costs for patients diagnosed with irritable bowel syndrome(IBS) and subtypes.METHODS Patients completed a standardized questionnaire concerning usage of healthcare resources, travel costs, meals, and productivity loss of patients when seeking treatment for IBS. Total annual costs per patient were calculated as the sum of direct(including medical and nonmedical) and indirect costs. Total annual costs per patient among various IBS subtypes were compared. Analysis of variance and bootstrapped independent sample t-tests were performed to determine differences between groups after controlling for IBS subtypes.RESULTS A total of 105 IBS patients(64.80% female), mean age of 57.12 years ± 10.31 years), mean disease duration of 4.31 years ± 5.40 years, were included. Total annual costs per patient were estimated as CNy18262.84(USD2933.08). Inpatient and outpatient healthcare use were major cost drivers, accounting for 46.41%and 23.36% of total annual costs, respectively. Productivity loss accounted for 25.32% of total annual costs. The proportions of direct and indirect costs were similarto published studies in other countries. Nationally, the total costs of managing IBS would amount to CNy123.83 billion(USD1.99 billion). Among the IBS subtypes, total annual costs per patient of IBS-M was highest at CNy18891.18(USD3034). Furthermore, there was significant difference in productivity loss among IBS subtypes(P = 0.031).CONCLUSION IBS imposes a huge economic burden on patients and healthcare systems, which could account for 3.3% of the total healthcare budget for the entire Chinese nation. More than two-thirds of total annual costs of IBS consist of inpatient and outpatient healthcare use. Among the subtypes, IBS-M patients appear to have the greatest economic burden but require further confirmation.