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The impacts of autonomous vehicles, coupled with greater inter-vehicle and system connectivity, may be far-reaching on several levels. They entail changes to (1) the demand and behavior side, (2) the supply of mobility services, and (3) network and facility operational performance. We focus here on their impact on traffic flow and operations, especially in mixed traffic situations in which autonomous vehicles share the road with regular, human-driven vehicles, along with connected vehicles that may also have some automated functions. These mixed traffic situations correspond to likely deployment scenarios of the technologies, especially in the long transition towards 100% deployment. We explain using elementary traffic science concepts how autonomous vehicles and connected vehicles are expected to increase the throughput of highway facilities, as well as improve the stability of the traffic stream. A microsimulation framework featuring varying behavioral mechanisms for the three classes of vehicles is introduced. The framework is used to examine the throughput and stability questions through a series of experiments under varying market penetration rates of autonomous and/or connected vehicles; at low market shares, the impacts are relatively minor on either throughput or stability. However, as market shares increase, autonomous vehicles exert a greater influence on both dimensions compared to the same shares of connected vehicles. Applications of the framework to examine the effectiveness of selected traffic management approaches are discussed, including dedicated lanes for autonomous vehicles (good only if its use is optional and when the market share of autonomous vehicles is greater than the percentage of nominal capacity represented by that lane), and speed harmonization.

This paper provides a systematic, multidimensional demographic analysis of the degree to which negative economic consequences of population aging can be mitigated by changes in migration and labor-force participation. Using a microsimulation population projection model accounting for 13 individual characteristics including education and immigration-related variables, we built scenarios of future changes in labor-force participation, migration volumes, and their educational composition and speed of integration for the 28 European Union (EU) member states. We study the consequences in terms of the conventional age-dependency ratio, the labor-force dependency ratio, and the productivity-weighted labor-force dependency ratio using education as a proxy of productivity, which accounts for the fact that not all individuals are equality productive in society. The results show that in terms of the more sophisticated ratios, population aging looks less daunting than when only considering age structure. In terms of policy options, lifting laborforce participation among the general population as in Sweden, and education-selective migration if accompanied by high integration, could even improve economic dependency. On the other hand, high immigration volumes combined with both low education and integration leads to increasing economic dependency. This shows the high stakes involved with integration outcomes under high migration volumes.

The impacts of autonomous vehicles, coupled with greater inter-vehicle and system connectivity, may be far-reaching on several levels. They entail changes to (1) the demand and behavior side, (2) the supply of mobility services, and (3) network and facility operational performance. We focus here on their impact on traffic flow and operations, especially in mixed traffic situations in which autonomous vehicles share the road with regular, human-driven vehicles, along with connected vehicles that may also have some automated functions. These mixed traffic situations correspond to likely deployment scenarios of the technologies, especially in the long transition towards 100% deployment. We explain using elementary traffic science concepts how autonomous vehicles and connected vehicles are expected to increase the throughput of highway facilities, as well as improve the stability of the traffic stream. A microsimulation framework featuring varying behavioral mechanisms for the three classes of vehicles is introduced. The framework is used to examine the throughput and stability questions through a series of experiments under varying market penetration rates of autonomous and/or connected vehicles; at low market shares, the impacts are relatively minor on either throughput or stability. However, as market shares increase, autonomous vehicles exert a greater influence on both dimensions compared to the same shares of connected vehicles. Applications of the framework to examine the effectiveness of selected traffic management approaches are discussed, including dedicated lanes for autonomous vehicles (good only if its use is optional and when the market share of autonomous vehicles is greater than the percentage of nominal capacity represented by that lane), and speed harmonization.

Close kin provide many important functions as adults age, affecting health, financial well-being, and happiness. Those without kin report higher rates of loneliness and experience elevated risks of chronic illness and nursing facility placement. Historical racial differences and recent shifts in core demographic rates suggest that white and black older adults in the United States may have unequal availability of close kin and that this gap in availability will widen in the coming decades. Whereas prior work explores the changing composition and size of the childless population or those without spouses, here we consider the kinless population of older adults with no living close family members and how this burden is changing for different race and sex groups. Using demographic microsimulation and the United States Census Bureau’s recent national projections of core demographic rates by race, we examine two definitions of kinlessness: those without a partner or living children, and those without a partner, children, siblings, or parents. Our results suggest dramatic growth in the size of the kinless population as well as increasing racial disparities in percentages kinless. These conclusions are driven by declines in marriage and are robust to different assumptions about the future trajectory of divorce rates or growth in nonmarital partnerships. Our findings draw attention to the potential expansion of older adult loneliness, which is increasingly considered a threat to population health, and the unequal burden kinlessness may place on black Americans.

This paper evaluates the operational and safety performance of a conventional single-lane roundabout (SLR) and a turbo roundabout (TR) using a mixed-methods approach. Field traffic counts and turning-movement matrices were collected at the studied intersection in Pezinok (Slovakia). The article describes capacity calculations according to national guidelines (TP 100 and TP 102) and the development of a calibrated and validated microsimulation model. Alternative designs—the existing SLR and a proposed TR conversion—were compared under observed morning and afternoon peak-hour conditions. Performance was assessed using standard operational indicators (delay, queue length, degree of saturation) and qualitative consideration of conflict points and weaving behavior. Simulation results for the case study indicate that the TR design reduced average delays and queue lengths and removed internal weaving compared with the SLR for the tested traffic distributions. However, the observed benefits are conditional: they depend on traffic volumes and turning-movement patterns, and may be reduced under very high total flows or when pedestrian and cyclist impacts are significant. Implications for applicability and limitations of TRs are discussed.

Driving experiences provided by the introduction of new vehicle technologies are directly impacting the criteria for road network design. New criteria should be taken into consideration by designers, researchers and car owners in order to assure traffic safety in changed conditions that will appear with, for example, introduction of Autonomous Vehicles (AVs) in everyday traffic. In this paper, roundabout safety level is analysed on the originally developed microsimulation model in circumstances where different numbers of AVs vehicles are mixed with Conventional Vehicles (CVs). Field data about speed and traffic volumes from existing roundabouts in Croatia were used for development of the model. The simulations done with the Surrogate Safety Assessment Model (SSAM) give some relevant highlights on how the introduction of AVs could change both operational and safety parameters at roundabouts. To further explore the effects on safety of roundabouts with the introduction of different shares of AVs, hypothetical safety treatments could be tested to explore whether their effects may change, leading to the estimation of a new set of Crash Modification Factors.

SummarySequential romosozumab-to-alendronate or sequential teriparatide-to-alendronate can be a cost-effective treatment option for postmenopausal women at very high risk of fracture.PurposeTo estimate the 10-year probability of a major osteoporotic fracture (MOF) at which sequential treatment with romosozumab or teriparatide followed by alendronate, compared with alendronate alone, becomes cost-effective in a UK setting.MethodsA microsimulation model with a Markov structure was used to simulate fractures, costs, and quality-adjusted life years (QALYs), in women receiving sequential treatment with either romosozumab or teriparatide followed by alendronate, compared with alendronate alone. Patients aged 50 to 90 years with a recent MOF, hip or spine fracture were followed from the start of a 5-year treatment until the age of 100 years or death. The analysis had a healthcare perspective. Efficacy of romosozumab, teriparatide and alendronate was derived from phase III randomised controlled trials. Resource use and unit costs were derived from the literature. Cost-effectiveness intervention threshold (CEIT), defined as the 10-year probability of a major osteoporotic fracture at which treatment becomes cost-effective, was compared with clinically appropriate intervention thresholds for bone-forming treatment in women with very high fracture risk as recommended by the UK National Osteoporosis Guideline Group (NOGG).ResultsThe base case analysis showed that sequential romosozumab-to-alendronate treatment was cost-effective from a 10-year MOF probability of 18–35% and above depending on age and site of sentinel fracture at a willingness to pay (WTP) of £30,000. For teriparatide-to-alendronate, treatment was cost-effective at a 10-year MOF probability of 27–57%. The results were sensitive to pricing of the drugs but relatively insensitive to treatment duration, romosozumab persistence assumptions, and site of sentinel fracture. The CEITs for romosozumab-to-alendronate treatment were lower than the clinical thresholds from the age of 70 years meaning that treatment could be considered both cost-effective and aligned with the NOGG treatment guidelines. By contrast, for teriparatide-to-alendronate the CEITs were higher than the clinical thresholds irrespective of age. However, cost-effective scenarios were found in the presence of strong clinical risk factors in addition to a recent sentinel fracture.ConclusionThe results of this study indicate that sequential romosozumab-to-alendronate or teriparatide-to-alendronate treatment can be a cost-effective treatment option for postmenopausal women at very high risk of fracture.

Nowadays, microsimulation method has been introduced to different fields, such as Social Science, Medicine research and Economic study. This method evaluates the effects of the proposed interventions or policies before they are implemented in the real world. In this article, we will concentrate on microsimulation method used in Social Science by firstly explaining two main streams in microsimulation world, Static approach and Dynamic approach. In the following section, the uncertainty of a Finnish static microsimulation model JUTTA is assessed and Toimtuki model, one of the sub-models in JUTTA is detected to have space to be more accurate. In order to do so, two experimental statistical models-Linear Regression model and Two-Stage Least Squares(2SLS) model are applied to it. From the results, we could conclude that both the Linear Regression and 2SLS successfully improves the accuracy of TOIMTUKI to some extent.