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Collisions resulting in injuries or fatalities occur more frequently at intersections. This is partly because safe navigation of intersections requires drivers to accurately observe and respond to other road users with conflicting paths. Previous studies have raised questions about how traffic control devices and the positioning of other road users might affect drivers' visual search strategies when navigating intersections. To address these questions, four left-turn-across-path (LTAP) scenarios were created by combining two types of traffic control devices (stop signs and traffic lights) with two hazard starting locations (central and peripheral). Seventy-four licensed drivers responded to all scenarios in a counterbalanced order using a full vehicle driving simulator. Eye-tracking glasses were used to monitor eye movements, both before and after hazard onset.

Collisions involving turn-across-path hazards are responsible for a disproportionate number of injuries and fatalities compared to collisions with other orientations. Previous investigations of turn-across-path hazards have found conflicting results regarding hazard detection and response behaviour of drivers, particularly for hazards with different onset conditions. Typically, hazards with abrupt onsets should attract attention more readily, however, the opposite trend for response times has been observed when the abrupt onset is a rapid change in speed, rather than a sudden appearance. This study compared two left-turn-across path hazards with different onsets. The abrupt onset hazard was an initially stopped vehicle that quickly accelerated into the participant drivers’ path, while the gradual onset hazard was already in motion as the participant driver approached.

Previously researched path intrusion scenarios include left-turning hazard vehicles which intrude laterally across the path of the through driver. A right turning vehicle, however, creates a scenario where a hazard which was initially travelling perpendicular to the driver can intrude into the through driver’s path without also occupying the adjacent through lanes. This hazard scenario has not been previously investigated. The purpose of this research was to determine driver response time (DRT) and response choice to a right turning vehicle that merges abruptly into the lane of the oncoming through driver. Using an Oktal full car driving simulator, 107 licenced drivers (NFemale = 57, NMale = 50) completed a five-minute practice drive followed by a ten-minute experimental drive containing two conditions of the right turn hazard, presented in a counterbalanced order.

Straight intersecting path or “side” collisions account for 12% of all motor vehicle crashes and 24% of fatalities. While previous research has examined driver responses to hazards striking from the right (near side), no research has quantified driver responses to hazards striking from the left (far side) of an intersection. The purpose of this study was to measure driver response time (DRT) and response choice for two versions of this scenario. In one condition, the hazard vehicle was initially stopped at the intersection before accelerating into the path of the participant driver. In the other condition, the hazard vehicle approached and entered the intersection while moving at a constant speed of 50 km/h.

Vehicle-pedestrian collisions account for 15% of fatal crashes in the USA, and there has been a twelve percent increase in fatal crashes in the USA from 2006 to 2015. Although research exists on the response time of drivers responding to pedestrian path intrusions, data on the response time of through drivers to jaywalking pedestrians crossing from the far side of the road has not been determined. Therefore, the purpose of this study was to quantify Driver Response Time (DRT) to a pedestrian that intrudes perpendicularly into the path of a vehicle from the far curb (adjacent to oncoming traffic). 50 (NFemale = 25; NMale = 25) licensed volunteer drivers took part in a study at the University of Guelph Driving Research in Virtual Environments (DRiVE) lab using an Oktal complete vehicle driving simulator.

Motor vehicle crashes with cyclists are on the rise, with a six percent increase in fatal crashes from 2006 to 2015 in the USA. Although some research exists on the response time of drivers to some types of path intrusions, data on the perception-response of through drivers to cyclists who fail to stop at a stop sign, and ride into the path of the vehicle has not been researched. The purpose of this study was to quantify the Driver Response Time (DRT) to a cyclist that intrudes perpendicularly in front of a through vehicle at an intersection where the driver has the right-of-way.

Left-turn crashes account for almost one quarter of all collisions. Although research has quantified the response time of drivers to left-turning vehicles with high acceleration profiles, research is lacking for driver responses to realistic left-turning vehicle acceleration. The purpose of this research was to determine the Driver Response Time (DRT) to a left-turning vehicle from the first lateral movement of the left-turning vehicle. The DRT was measured from first lateral movement of the left turning vehicle, until the through driver reacts, whether by touching the brake pedal, swerving, releasing/applying the accelerator, or a combination of these inputs. Ninety-eight (NFemale = 48; NMale = 50) licensed volunteer drivers took part in a study at the University of Guelph Driving Research in Virtual Environments (DRiVE) lab using an Oktal complete vehicle driving simulator.

There is anecdotal evidence of drivers blindly following in-vehicle navigation system (IVNS) commands. IVNSs have shown to be distracting and mishaps with the device have entered popular culture as a source of comedy. Manufactures have reacted by warning drivers of the dangers involved in operating the devices and in some cases prevent address input while moving. While IVNSs are increasingly being used, do drivers perceive their use as distracting, potentially misleading, and thus dangerous? We conducted an online survey of over 200 drivers to determine their attitudes toward safety while using these devices. This was followed by a series of interviews with an additional 20 drivers to provide more in-depth results. Drivers reported that distraction is not a big issue for them when using an IVNS, with only 8% reporting that the device was too distracting at times.

The following abstract is that provided to first year undergraduate students as part of the recruitment effort for 1st Year Seminar Courses at the University of Guelph. When humankind begins the colonization of the moon or Mars, we will be bringing along more of Earth than one might think. A number of space and government agencies around the world, including researchers at the Controlled Environment Systems Research Facility, University of Guelph, are involved in the design and engineering of self-contained ecosystems based on Earthly biological processes. These processes can be harnessed, with complementary physical and chemical technologies to support human life (food production, air revitalization, psychology) in the hostile conditions of space.

In-Vehicle Information Systems (IVIS) provide vehicle travelers with a range of useful information, including road condition, weather broadcasting, GPS maps, and city navigation. It is widely acknowledged that a single IVIS design does not fit everyone as users can have different interface and content preferences. T hese preferences are often related to age, gender, experience, and other demographic, social, and psychological characteristics. IVIS need to be capable of adapting to the context. This paper reviews adaptation techniques found in user-adaptive systems and develops a mapping between adaptation techniques and the characteristics of the system being adapted. This mapping is then used to show that adaptation techniques for user-adaptive systems can be applied to the design of IVIS. As IVIS become popular and their functionalities become more diverse, driver distraction will increase due to increased cognitive load.

More than a dozen design and evaluation guidelines exist for in-vehicle navigation devices, and are used in areas ranging from manufacturing to government policymaking. Currently, there is no central body of knowledge or one complete set of guidelines to help guide users in designing and evaluating safe, usable and ergonomic devices. To understand the value of the current guidelines, an online survey was constructed to evaluate users' knowledge, use and opinions. Results from the survey show that respondents found many guidelines to be impractical, difficult to apply, and irrelevant to their work. While guidelines from UMTRI, Transport Canada and SAE were considered the most useful, many participants were unfamiliar with them. Engineers, designers and researchers indicate that guidelines are incomplete, not up-to-date, and don't address all of the issues arising in designing and evaluating in-vehicle navigation devices.

Electronic navigational systems allow drivers to receive travel directions while driving, rather than preplanning a route. This additional attentional load on drivers might prove to be hazardous -- particularly for older adults who have greater difficulties multitasking and switching their attention between different parts of the visual field. A driving simulator was used to evaluate the perception time to critical events in the presence and absence of a navigation system with young (n=18, age=18.8years SD= 0.7years) and older drivers (n=15, age=73.1years, SD=6.1years). The results of this study indicated that though older drivers were slower to react to critical events, and both groups were faster to react to pedestrian incursions than sudden light changes, messages from the travel system did not interfere significantly with perception reaction time in either group.

For a planetary base, a reliable life support system including food and water supply, gas generation and waste management is a condition sine qua non. While for a short-term period the life support system may be an open loop, i.e. water, gases and food provided from the Earth, for long-term missions the system has to become more and more regenerative. Advanced life support systems with biological regenerative processes have been studied for many years and the processes within the different compartments are rather complete and known to a certain extent. The knowledge of the associated interfaces, the management of the input and output phases: liquid, solid, gas, between compartments, has been limited. Nowadays, it is well accepted that the management of these phases induces generic problems like capture, separation, transfer, mixing, and buffering. A first ESA study on these subjects started mid 2003.

The production of essential commodities (O2, H2 O, and edible biomass) and removal of CO2 by higher plants in bioregenerative life support systems would be seriously limited by the occurrence of disease epidemics. Among several treatment possibilities is ultraviolet (UV) radiation, which is one of the preferred sterilization techniques due to cost considerations and observed effectiveness against pathogens in hydroponic systems. Doses of 20 to 40 mW.s/cm2 as estimated in a laboratory flowthrough apparatus inactivated 99.99% of Pythium aphanidermatum, a common pathogen of hydroponic crops. Inactivation increased logarithmically with UV radiation dose. NCER (Net Carbon Exchange Rate) provides an indirect method to determine the effectiveness of UV in reducing Pythium infection, by measuring any changes in primary plant productivity.

A biofiltration system was tested to remove low levels of acetone from an indoor space. The biofilters were subjected to a range of air fluxes and concentrations of acetone between 100 and 500 ppbv. Passing low levels of acetone through a canopy of green plants did not improve the quality of the air. However, acetone removal by the biofilters with living moss as a principle substrate, reached a maximum of between 1 and 1.6 μmol s-1 m-2 with a loading rate of approximately 2 μmol s-1 m-2. Generally the removal efficiency decreased with increased loading rates over a range of air fluxes (0.05 to 0.2 m s-1) but appear to increase with loading within the slower fluxes. Neither ZERO nor FIRST order kinetics could adequately describe removal. Instead an empirical model that described the natural logarithm of the unloading rate as a function of the natural logarithm of the loading rate and the natural logarithm of the inverse of the air flux fit the data well.

The occurrence of disease epidemics in bioregenerative life support systems would seriously limit the production of essential life support requirements. The capacity of diseased plants in closed environment chambers to scrub CO2 was studied with lettuce plants infected with a common greenhouse pathogen, Pythium.At harvest, infected lettuce showed less edible biomass, decreased leaf area, and reduced photosynthesis averaging 50% on a per chamber basis. These results and others are discussed to show the potential of using existing instrumentation in life support systems to monitor the health of the plant canopy, predicting early onset of disease and refining remediation strategies.

In dense plant canopies, shaded leaves represent considerable unused photosynthetic capacity that can be exploited to improve production in closed environments. By coupling Fusion Systems Solar 1000 microwave powered lights to 100 mm diameter glass tubes lined with 3M Optical Lighting Film, energy equivalent to approximately 420 μmol m-2 s-1 PAR was delivered to the inner canopy of a developing soybean (Glycine max L. Merr. cv. Secord) crop. Inner canopy irradiation enhanced plant growth and altered biomass partitioning within the canopy. With inner canopy lighting, edible biomass, carbon dioxide removal and water and oxygen production were increased by 9, 30, 160, and 100 percent respectively. Ethylene production in the closed environment was also increased during several months of canopy development.