Science.gov

Sample records for bicycle commuting

  1. Bicycle weight and commuting time: randomised trial

    PubMed Central

    2010-01-01

    Objective To determine whether the author’s 20.9 lb (9.5 kg) carbon frame bicycle reduced commuting time compared with his 29.75 lb (13.5 kg) steel frame bicycle. Design Randomised trial. Setting Sheffield and Chesterfield, United Kingdom, between mid-January 2010 and mid-July 2010. Participants One consultant in anaesthesia and intensive care. Main outcome measure Total time to complete the 27 mile (43.5 kilometre) journey from Sheffield to Chesterfield Royal Hospital and back. Results The total distance travelled on the steel frame bicycle during the study period was 809 miles (1302 km) and on the carbon frame bicycle was 711 miles (1144 km). The difference in the mean journey time between the steel and carbon bicycles was 00:00:32 (hr:min:sec; 95% CI –00:03:34 to 00:02:30; P=0.72). Conclusions A lighter bicycle did not lead to a detectable difference in commuting time. Cyclists may find it more cost effective to reduce their own weight rather than to purchase a lighter bicycle. PMID:21148220

  2. Sandia bicycle commuters group -- pollution prevention at Sandia National Laboratories, New Mexico

    SciTech Connect

    Wrons, R.

    1998-06-01

    The Sandia Bicycle Commuters Group (SBCG) formed three years ago for the purpose of addressing issues that impact the bicycle commuting option. The meeting that launched the SBCG was scheduled in conjunction with National Bike-to-Work day in May 1995. Results from a survey handed out at the meeting solidly confirmed the issues and that an advocacy group was needed. The purpose statement for the Group headlines its web site and brochure: ``Existing to assist and educate the SNL workforce bicyclist on issues regarding Kirtland Air Force Base (KAFB) access, safety and bicycle-supporting facilities, in order to promote bicycling as an effective and enjoyable means of commuting.`` The SNL Pollution Prevention (P2) Team`s challenge to the SNL workforce is to ``prevent pollution, conserve natural resources, and save money``. In the first winter of its existence, the SBCG sponsored a winter commute contest in conjunction with the City`s Clean Air Campaign (CAC). The intent of the CAC is to promote alternative (to the single-occupant vehicle) commuting during the Winter Pollution Advisory Period (October 1--February 28), when the City runs the greatest risk of exceeding federal pollution limits.

  3. Inhaled particle counts on bicycle commute routes of low and high proximity to motorised traffic

    NASA Astrophysics Data System (ADS)

    Cole-Hunter, Tom; Morawska, Lidia; Stewart, Ian; Jayaratne, Rohan; Solomon, Colin

    2012-12-01

    Frequent exposure to ultrafine particles (UFP) is associated with detrimental effects on cardiopulmonary function and health. UFP dose and therefore the associated health risk are a factor of exposure frequency, duration, and magnitude of (therefore also proximity to) a UFP emission source. Bicycle commuters using on-road routes during peak traffic times are sharing a microenvironment with high levels of motorised traffic, a major UFP emission source. Inhaled particle counts were measured on popular pre-identified bicycle commute route alterations of low (LOW) and high (HIGH) proximity to motorised traffic to the same inner-city destination at peak commute traffic times. During commute, real-time particle number concentration (PNC; mostly in the UFP range) and particle diameter (PD), heart rate, geographical location, and meteorological variables were measured. To determine inhaled particle counts, ventilation rate was calculated from heart-rate-ventilation associations, produced from periodic exercise testing. Total mean PNC of LOW, compared to HIGH, was reduced (1.56 × e4 ± 0.38 × e4 versus 3.06 × e4 ± 0.53 × e4 ppcc; p = 0.012). Total estimated ventilation rate did not differ significantly between LOW and HIGH (43 ± 5 versus 46 ± 9 L min-1; p = 0.136); however, due to total mean PNC, minute inhaled particle counts were 48% lower in LOW, compared to HIGH (6.71 × e8 ± 1.30 × e8 versus 14.08 × e8 ± 1.77 × e8 particles total; p = 0.003). For bicycle commuting at peak morning commute times, inhaled particle counts and therefore cardiopulmonary health risk may be substantially reduced by decreasing proximity to motorised traffic, which should be considered by both bicycle commuters and urban planners.

  4. Tertiary Student Attitudes to Bicycle Commuting in a Regional Australian University

    ERIC Educational Resources Information Center

    Whannell, Patricia; Whannell, Robert; White, Richard

    2012-01-01

    Purpose: The purpose of this paper is to provide executive management at a regional university with empirical data to justify, or otherwise, a substantial outlay of funds to support bicycle commuting as a viable strategy for the reduction of traffic congestion. Design/methodology/approach: A custom designed questionnaire was completed by 270…

  5. The Societal Costs and Benefits of Commuter Bicycling: Simulating the Effects of Specific Policies Using System Dynamics Modeling

    PubMed Central

    Connor, Jennie; Witten, Karen; Kearns, Robin; Rees, David; Woodward, Alistair

    2014-01-01

    Background: Shifting to active modes of transport in the trip to work can achieve substantial co-benefits for health, social equity, and climate change mitigation. Previous integrated modeling of transport scenarios has assumed active transport mode share and has been unable to incorporate acknowledged system feedbacks. Objectives: We compared the effects of policies to increase bicycle commuting in a car-dominated city and explored the role of participatory modeling to support transport planning in the face of complexity. Methods: We used system dynamics modeling (SDM) to compare realistic policies, incorporating feedback effects, nonlinear relationships, and time delays between variables. We developed a system dynamics model of commuter bicycling through interviews and workshops with policy, community, and academic stakeholders. We incorporated best available evidence to simulate five policy scenarios over the next 40 years in Auckland, New Zealand. Injury, physical activity, fuel costs, air pollution, and carbon emissions outcomes were simulated. Results: Using the simulation model, we demonstrated the kinds of policies that would likely be needed to change a historical pattern of decline in cycling into a pattern of growth that would meet policy goals. Our model projections suggest that transforming urban roads over the next 40 years, using best practice physical separation on main roads and bicycle-friendly speed reduction on local streets, would yield benefits 10–25 times greater than costs. Conclusions: To our knowledge, this is the first integrated simulation model of future specific bicycling policies. Our projections provide practical evidence that may be used by health and transport policy makers to optimize the benefits of transport bicycling while minimizing negative consequences in a cost-effective manner. The modeling process enhanced understanding by a range of stakeholders of cycling as a complex system. Participatory SDM can be a helpful method

  6. Personal exposure to particulate matter in commuters using different transport modes (bus, bicycle, car and subway) in an assigned route in downtown Santiago, Chile.

    PubMed

    Suárez, Liliana; Mesías, Stephanie; Iglesias, Verónica; Silva, Claudio; Cáceres, Dante D; Ruiz-Rudolph, Pablo

    2014-05-01

    The objective of this study was to compare personal exposure to particulate matter (fine and ultrafine particles) in commuters using different transport modes (bicycle, bus, car and subway) in a busy, assigned route in downtown Santiago, Chile. Volunteers carrying personal samplers completed scheduled commutes during the morning rush hours, while central site measurements were conducted in parallel. A total of 137 valid commutes were assessed. The impact of central site, traffic and other variables was explored with regression models. PM2.5 personal concentrations were equal to or slightly above central site measurements, while UFP personal concentrations were above them. Regression models showed impacts of both background levels and traffic emissions on personal PM2.5 and UFP exposure. Traffic impacts varied with transport modes. Estimates of traffic impacts on personal PM2.5 exposure were 2.0, 13.0, 16.9 and 17.5 μg m(-3), for car, bicycle, subway and bus, respectively; while for UFP exposure were 8400, 16 200, 25 600 and 30 100 counts per cm(3), for subway, car, bicycle and bus, respectively. After controlling the central site and transport mode, higher temperatures increased PM2.5 exposure and decreased UFP ones, while the wind direction affected UFP personal exposure. In conclusion, we found significant impacts of both central site background measurements and traffic emissions on personal exposure of volunteer commuters in an assigned route in Santiago, with impacts varying with transport modes.

  7. Utility of an alternative bicycle commute route of lower proximity to motorised traffic in decreasing exposure to ultra-fine particles, respiratory symptoms and airway inflammation – a structured exposure experiment

    PubMed Central

    2013-01-01

    Background Bicycle commuting in an urban environment of high air pollution is known to be a potential health risk, especially for susceptible individuals. While risk management strategies aimed to reduce exposure to motorised traffic emissions have been suggested, only limited studies have assessed the utility of such strategies in real-world circumstances. Objectives The potential to lower exposure to ultrafine particles (UFP; < 0.1 μm) during bicycle commuting by reducing proximity to motorised traffic was investigated with real-time air pollution and intermittent acute inflammatory measurements in healthy individuals using their typical higher proximity, and an alternative lower proximity, bicycle commute route. Methods Thirty-five healthy adults (mean ± SD: age = 39 ± 11 yr; 29% female) completed two return trips, one each in the condition of their typical route (HIGH) and a pre-determined alternative route of lower proximity to motorised traffic (LOW); proximity being determined by the proportion of on-road cycle paths. Particle number concentration (PNC) and diameter (PD) were monitored in-commute in real-time. Acute inflammatory indices of respiratory symptoms (as a scalar of frequency from very low to very high / 1 to 5), lung function and spontaneous sputum (for inflammatory cell analyses) were collected immediately pre-commute, and immediately and three hours post-commute. Results In the condition of LOW, compared to in the condition of HIGH, there was a significant decrease in mean PNC (1.91 x e4 ± 0.93 × e4 ppcc vs. 2.95 × e4 ± 1.50 × e4 ppcc; p ≤ 0.001), and the mean frequency of in-commute offensive odour detection (2.1 vs. 2.8; p = 0.019), dust and soot observation (1.7 vs. 2.3; p = 0.038) and nasopharyngeal irritation (1.5 vs. 1.9; p = 0.007). There were no significant differences between LOW and HIGH in the commute distance and duration (12.8 ± 7.1 vs. 12.0 ± 6.9 km and 44 ± 17 vs. 42 ± 17 min, respectively), or other indices of

  8. University Opinion Poll 8A: Bicycles on Campus.

    ERIC Educational Resources Information Center

    Matross, Ronald; And Others

    The University Opinion Poll conducted a two-stage survey of campus bicycle usage and opinions toward campus bicycle facilities. In the first stage, 952 persons, 78% of a random sample of students and staff reported their commuting habits and opinions about campus bicycle lanes. In the second stage, 139 persons, 84% of a sample of student and staff…

  9. The influence of a bicycle commuter's appearance on drivers' overtaking proximities: an on-road test of bicyclist stereotypes, high-visibility clothing and safety aids in the United Kingdom.

    PubMed

    Walker, Ian; Garrard, Ian; Jowitt, Felicity

    2014-03-01

    This study looked at whether drivers overtaking a bicyclist changed the proximities of their passes in response to the level of experience and skill signalled by the bicyclist's appearance. Seven outfits were tested, ranging from a stereotypical sport rider's outfit, portraying high experience and skill, to a vest with 'novice cyclist' printed on the back, portraying low experience. A high-visibility bicycling jacket was also used, as were two commercially available safety vests, one featuring a prominent mention of the word 'police' and a warning that the rider was video-recording their journey, and one modelled after a police officer's jacket but with a letter changed so it read 'POLITE'. An ultrasonic distance sensor recorded the space left by vehicles passing the bicyclist on a regular commuting route. 5690 data points fulfilled the criteria for the study and were included in the analyses. The only outfit associated with a significant change in mean passing proximities was the police/video-recording jacket. Contrary to predictions, drivers treated the sports outfit and the 'novice cyclist' outfit equivalently, suggesting they do not adjust overtaking proximity as a function of a rider's perceived experience. Notably, whilst some outfits seemed to discourage motorists from passing within 1m of the rider, approximately 1-2% of overtakes came within 50 cm no matter what outfit was worn. This suggests there is little riders can do, by altering their appearance, to prevent the very closest overtakes; it is suggested that infrastructural, educational or legal measures are more promising for preventing drivers from passing extremely close to bicyclists. PMID:24333770

  10. Bicycling injuries.

    PubMed

    Silberman, Marc R

    2013-01-01

    Bicycling injuries can be classified into bicycle contact, traumatic, and overuse injuries. Despite the popularity of cycling, there are few scientific studies regarding injuries. Epidemiological studies are difficult to compare due to different methodologies and the diverse population of cyclists studied. There are only three studies conducted on top level professionals. Ninety-four percent of professionals in 1 year have experienced at least one overuse injury. Most overuse injuries are mild with limited time off the bike. The most common site of overuse injury is the knee, and the most common site of traumatic injury is the shoulder, with the clavicle having the most common fracture. Many overuse and bicycle contact ailments are relieved with simple bike adjustments.

  11. Bicycle Wheel

    NASA Technical Reports Server (NTRS)

    1991-01-01

    An aerodynamic bicycle wheel developed by two DuPont engineers and a California company incorporates research into NASA airfoils. Computer modeling was accomplished with MSC/NASTRAN. Each of the three spokes in the wheel is, in effect, an airfoil, maximizing aerodynamic efficiency for racing.

  12. The Bicycle Driver's Guide.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    Designed to emphasize the concept of the bicycle driver vs. the popular term, bicycle rider, this manual contains guidelines on bicycle safety, addressing itself both to parents and children. The main section topics are: (1) parent responsibility; (2) choosing a bicycle, fitting it to the child, and learning to drive; (3) bicycle equipment,…

  13. Making almost commuting matrices commute

    SciTech Connect

    Hastings, Matthew B

    2008-01-01

    Suppose two Hermitian matrices A, B almost commute ({parallel}[A,B]{parallel} {<=} {delta}). Are they close to a commuting pair of Hermitian matrices, A', B', with {parallel}A-A'{parallel},{parallel}B-B'{parallel} {<=} {epsilon}? A theorem of H. Lin shows that this is uniformly true, in that for every {epsilon} > 0 there exists a {delta} > 0, independent of the size N of the matrices, for which almost commuting implies being close to a commuting pair. However, this theorem does not specifiy how {delta} depends on {epsilon}. We give uniform bounds relating {delta} and {epsilon}. The proof is constructive, giving an explicit algorithm to construct A' and B'. We provide tighter bounds in the case of block tridiagonal and tridiagnonal matrices. Within the context of quantum measurement, this implies an algorithm to construct a basis in which we can make a projective measurement that approximately measures two approximately commuting operators simultaneously. Finally, we comment briefly on the case of approximately measuring three or more approximately commuting operators using POVMs (positive operator-valued measures) instead of projective measurements.

  14. Physical activity during leisure and commuting in Tianjin, China.

    PubMed Central

    Hu, Gang; Pekkarinen, Heikki; Hänninen, Osmo; Yu, Zhijie; Tian, Huiguang; Guo, Zeyu; Nissinen, Aulikki

    2002-01-01

    OBJECTIVE: To investigate physical activity during leisure time and commuting among persons aged 15-69 years in the urban population of Tianjin, China, and to assess its associations with demographic and health-related characteristics. METHODS: In 1996 a cross-sectional survey of 2002 males and 1974 females provided information on physical activity during leisure time and commuting and on demographics and health behaviours. FINDINGS: No leisure-time physical activity was engaged in by 67% of females and 61% of males. However, only 4% of females and 9% of males reported an absence of physical activity during commuting. The mean duration of leisure-time physical activity for the whole population was about 10 min per day. The average commuting time on foot or by bicycle was about 30 min. Leisure-time physical activity was more frequent among highly educated people, people with high incomes, white-collar workers, married people, non-smokers, or people commuting on foot or by bicycle than among other people. Persons with low incomes, male blue-collar workers and married people were more likely than others to engage in 30 min or more per day of physical activity on foot or by bicycle when commuting. CONCLUSION: People in Tianjin engaged in a high level of physical activity when commuting and a low level of leisure-time physical activity. PMID:12571720

  15. Bicycling and Hostels.

    ERIC Educational Resources Information Center

    Kyle, George M., Ed.

    1974-01-01

    This collection of articles focuses on bicycling and hosteling as important recreational activities that can (a) help conserve energy, (b) benefit the economy offering a low-cost pasttime, and (c) stimulate foreign travel to the U.S. Articles include the following: (a) "Bicycling and Hosteling--An American Partnership," (b) "The Return of the…

  16. Bicycle Safety in Action.

    ERIC Educational Resources Information Center

    National Commission on Safety Education, Washington, DC.

    This material was designed to assist schools in teaching bicycle safety. As the population grows and competition for road space increases, it is more imperative than ever that we concentrate attention on the need for caution among pupil cyclists. The pamphlet: (1) discusses the role of bicycle safety in classroom instruction and in student…

  17. Bicycle Promotion Plan

    SciTech Connect

    Simone, G. A.

    1981-03-09

    The objective of this Bicycle Promotion Plan is to outline a set of recommendations and supporting strategies for implementation by the US DOE toward increased use of the bicycle for energy conservation. The recommendations are designed in such a way as to function in concert with: (1) bicycle programs administered by other Federal government agencies; and (2) related programs and activities already sponsored by DOE. The approach to preparation of the Plan involved a review of all current and planned bicycle promotion programs at the Federal level as well as a review of the array of lierature on the subject. The UniWorld project staff also interacted with several DOE program offices, in order to determine the extent to which they might appropriately contribute to the implementation of bicycle promotional efforts. A synthesis of all the information gathered was published in January of 1981 as a part of the project (The Bicycle Program Review). Based upon this information and an examination of the barriers to bicycle use identified by bicycle transportation specialists in the field, UniWorld developed a series of the most potentially effective recommendations and program strategies for implementation by DOE. The recommendations address activities that could be undertaken in conjunction with existing DOE programs, new developments that might be considered to fulfill critical needs in the field, and interagency efforts that DOE could play a role in.

  18. Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK.

    PubMed

    Mburu, Lucy Waruguru; Helbich, Marco

    2016-01-01

    Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops) was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use. PMID:27643788

  19. Environmental Risk Factors influencing Bicycle Theft: A Spatial Analysis in London, UK

    PubMed Central

    Helbich, Marco

    2016-01-01

    Urban authorities are continuously drawing up policies to promote cycling among commuters. However, these initiatives are counterproductive for the targeted objectives because they increase opportunities for bicycle theft. This paper explores Inner London as a case study to address place-specific risk factors for bicycle theft at the street-segment level while controlling for seasonal variation. The presence of certain public amenities (e.g., bicycle stands, railway stations, pawnshops) was evaluated against locations of bicycle theft between 2013 and 2016 and risk effects were estimated using negative binomial regression models. Results showed that a greater level of risk stemmed from land-use facilities than from area-based socioeconomic status. The presence of facilities such as train stations, vacant houses, pawnbrokers and payday lenders increased bicycle theft, but no evidence was found that linked police stations with crime levels. The findings have significant implications for urban crime prevention with respect to non-residential land use. PMID:27643788

  20. Street Wise Part 1: Promoting Safe Bicycling and Walking to School

    ERIC Educational Resources Information Center

    Crider, Linda B.; Hall, Amanda K.

    2005-01-01

    If school is a child's "workplace," the daily trip to school is the child's "commute." This trip may be taken in a car or bus, but if it is taken on foot or by bicycle, it offers children multiple opportunities for regular physical activity--a vitally important benefit at a time when overweight and related disorders are increasingly common. This…

  1. Ecological Analysis of Parking Prices and Active Commuting in US Cities, 2009.

    PubMed

    Whitfield, Geoffrey P; Wendel, Arthur M; Auchincloss, Amy H

    2016-01-01

    We conducted an ecological study to determine whether parking prices are associated with active commuting across US cities. We obtained parking prices for 107 US cities from the Drexel University Central Business District Public Parking Survey, obtained city prevalence of walking and bicycling to work from the American Community Survey, and used weighted least squares linear regression to explore associations between parking prices and active commuting. After adjusting for several covariates, walking to work was 3.1% higher for every additional dollar charged for off-street daily parking, but only among more densely populated cities, and no such association was detected for bicycling to work. These preliminary results hint at the potential for parking policies to influence commuting mode choice, a link that city planners and public health officials could consider when evaluating parking policies and active transportation behaviors. PMID:27609301

  2. Ecological Analysis of Parking Prices and Active Commuting in US Cities, 2009

    PubMed Central

    Wendel, Arthur M.; Auchincloss, Amy H.

    2016-01-01

    We conducted an ecological study to determine whether parking prices are associated with active commuting across US cities. We obtained parking prices for 107 US cities from the Drexel University Central Business District Public Parking Survey, obtained city prevalence of walking and bicycling to work from the American Community Survey, and used weighted least squares linear regression to explore associations between parking prices and active commuting. After adjusting for several covariates, walking to work was 3.1% higher for every additional dollar charged for off-street daily parking, but only among more densely populated cities, and no such association was detected for bicycling to work. These preliminary results hint at the potential for parking policies to influence commuting mode choice, a link that city planners and public health officials could consider when evaluating parking policies and active transportation behaviors. PMID:27609301

  3. Bicycle Trailers Increase Mobility

    ERIC Educational Resources Information Center

    Exceptional Parent, 2006

    2006-01-01

    This article describes the experiences of an exceptional parent who always takes his daughter for rides in a CycleTote special needs bicycle trailer. Dennis Foster, an exceptional parent from Commerce, Oklahoma, found that taking his twenty-eight-year-old daughter Hasha for rides has made her happy. Hasha has been diagnosed with cerebral palsy.

  4. Low Vision Bicycling.

    ERIC Educational Resources Information Center

    Connor, M.

    1992-01-01

    This article considers bicycling as a means of transportation, not recreation, for individuals with low vision. Considered are evaluation of capabilities, watching for child cyclists, central and peripheral field loss, necessary equipment, potential problems, seasonal and weather considerations, night riding, route planning, basic visual skills…

  5. The safety of electrically assisted bicycles compared to classic bicycles.

    PubMed

    Schepers, J P; Fishman, E; den Hertog, P; Wolt, K Klein; Schwab, A L

    2014-12-01

    Use of electrically assisted bicycles with a maximum speed of 25 km/h is rapidly increasing. This growth has been particularly rapid in the Netherlands, yet very little research has been conducted to assess the road safety implications. This case-control study compares the likelihood of crashes for which treatment at an emergency department is needed and injury consequences for electric bicycles to classic bicycles in the Netherlands among users of 16 years and older. Data were gathered through a survey of victims treated at emergency departments. Additionally, a survey of cyclists without any known crash experience, drawn from a panel of the Dutch population acted as a control sample. Logistic regression analysis is used to compare the risk of crashes with electric and classical bicycles requiring treatment at an emergency department. Among the victims treated at an emergency department we compared those being hospitalized to those being send home after the treatment at the emergency department to compare the injury consequences between electric and classical bicycle victims. The results suggest that, after controlling for age, gender and amount of bicycle use, electric bicycle users are more likely to be involved in a crash that requires treatment at an emergency department due to a crash. Crashes with electric bicycles are about equally severe as crashes with classic bicycles. We advise further research to develop policies to minimize the risk and maximize the health benefits for users of electric bicycles.

  6. The safety of electrically assisted bicycles compared to classic bicycles.

    PubMed

    Schepers, J P; Fishman, E; den Hertog, P; Wolt, K Klein; Schwab, A L

    2014-12-01

    Use of electrically assisted bicycles with a maximum speed of 25 km/h is rapidly increasing. This growth has been particularly rapid in the Netherlands, yet very little research has been conducted to assess the road safety implications. This case-control study compares the likelihood of crashes for which treatment at an emergency department is needed and injury consequences for electric bicycles to classic bicycles in the Netherlands among users of 16 years and older. Data were gathered through a survey of victims treated at emergency departments. Additionally, a survey of cyclists without any known crash experience, drawn from a panel of the Dutch population acted as a control sample. Logistic regression analysis is used to compare the risk of crashes with electric and classical bicycles requiring treatment at an emergency department. Among the victims treated at an emergency department we compared those being hospitalized to those being send home after the treatment at the emergency department to compare the injury consequences between electric and classical bicycle victims. The results suggest that, after controlling for age, gender and amount of bicycle use, electric bicycle users are more likely to be involved in a crash that requires treatment at an emergency department due to a crash. Crashes with electric bicycles are about equally severe as crashes with classic bicycles. We advise further research to develop policies to minimize the risk and maximize the health benefits for users of electric bicycles. PMID:25238296

  7. The active commuting route environment scale (ACRES): development and evaluation

    PubMed Central

    2010-01-01

    Background Route environments can be a potentially important factor in influencing people's behaviours in relation to active commuting. To better understand these possible relationships, assessments of route environments are needed. We therefore developed a scale; the Active Commuting Route Environment Scale (ACRES), for the assessment of bicyclists' and pedestrians' perceptions of their commuting route environments. Here we will report on the development and the results of validity and reliability assessments thereof. Methods Active commuters (n = 54) were recruited when they bicycled in Stockholm, Sweden. Traffic planning and environmental experts from the Municipality of Stockholm were assembled to form an expert panel (n = 24). The active commuters responded to the scale on two occasions, and the expert panel responded to it once. To test criterion-related validity, differences in ratings of the inner urban and suburban environments of Greater Stockholm were compared between the experts and the commuters. Furthermore, four items were compared with existing objective measures. Test-retest reproducibility was assessed with three types of analysis: order effect, typical error and intraclass correlation. Results There was a concordance in sizes and directions of differences in ratings of inner urban and suburban environments between the experts and the commuters. Furthermore, both groups' ratings were in line with existing objectively measured differences between the two environmental settings. Order effects between test and retest were observed in 6 of 36 items. The typical errors ranged from 0.93 to 2.54, and the intraclass correlation coefficients ranged from 'moderate' (0.42) to 'almost perfect' (0.87). Conclusions The ACRES was characterized by considerable criterion-related validity and reasonable test-retest reproducibility. PMID:20609250

  8. Active commuting to school

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Declines in physical activity levels have coincided with increasing rates of obesity in children. This is problematic because physical activity has been shown to attenuate weight gain in children. Active commuting to school is one way of increasing children's physical activity. However, given the hi...

  9. Connecting with Commuters

    ERIC Educational Resources Information Center

    Ullman, Ellen

    2011-01-01

    For the last few years, Georgia State University has taken steps toward becoming a more traditional college instead of a commuter school. It bought two Atlanta hotels to be used as residence halls, started a football team, and is building townhouses for Greek fraternities and sororities. "When alumni come back to campus, they are shocked at all…

  10. Bicycling to university: evaluation of a bicycle-sharing program in Spain.

    PubMed

    Molina-García, Javier; Castillo, Isabel; Queralt, Ana; Sallis, James F

    2015-06-01

    This study examined the change in behavioral stages (e.g. contemplation, action and maintenance) of cycling to university before and after the implementation of a new public bicycle share program (PBSP) and promotion of its use. The study also determined the change in the prevalence, correlates of PBSP use and potential role in the promotion of healthy weight. An 8-month follow-up cross-sectional study (September 2010-April 2011) was carried out among undergraduate students during the first season of implementation of the PBSP in Valencia, Spain. The sample was 173 students (68.2% female) with a mean age of 21.3 years (SD 3.06) who attended a PBSP promotional session. The data were collected by questionnaire. Results indicated a significant increase of 14.6% in the action/maintenance stage of change and showed that 19% of the participants were PBSP users 8 months later. The behavioral stage did not change when students always had access to car/motorbike, lived further than 5 km from the university and had no bicycle stations within 250 m from home. Those most likely to start using PBSP were students who were in the contemplation stage, perceived fewer environmental and safety barriers to active commuting and had one or more stations within 250 m of home. PBSP users expended ∼257 metabolic equivalent·minutes/week bicycling to university, and there was a small reduction in BMI. Findings suggest that PBSPs can be considered as useful promoters of cycling behavior and may contribute to weight control in university students.

  11. The Bicycle Assembly Line Game

    ERIC Educational Resources Information Center

    Klotz, Dorothy

    2011-01-01

    "The Bicycle Assembly Line Game" is a team-based, in-class activity that helps students develop a basic understanding of continuously operating processes. Each team of 7-10 students selects one of seven prefigured bicycle assembly lines to operate. The lines are run in real-time, and the team that operates the line that yields the…

  12. Association Between User-Generated Commuting Data and Population-Representative Active Commuting Surveillance Data - Four Cities, 2014-2015.

    PubMed

    Whitfield, Geoffrey P; Ussery, Emily N; Riordan, Brian; Wendel, Arthur M

    2016-01-01

    Creating environments that support all types of physical activity, including active transportation, is a public health priority (1). Public health surveillance that identifies the locations where community members walk and bicycle (i.e., engage in active transportation) can inform such efforts. Traditional population-representative active transportation surveillance incurs a considerable time lag between data collection and dissemination, and often lacks geographic specificity (2). Conversely, user-generated active transportation data from Global Positioning System (GPS)-based activity tracking devices and mobile applications can provide near real-time information, but might be subject to self-selection bias among users. CDC analyzed the association between GPS-based commuting data from a company that allows tracking of activity with a mobile application (Strava, Inc., San Francisco, California) and population-representative commuting data from the U.S. Census Bureau's American Community Survey (ACS) (3) for four U.S. cities. The level of analysis was the Census block group. The number of GPS-tracked commuters in Strava was associated with the number of ACS active commuters (Spearman's rho = 0.60), suggesting block groups were ranked similarly based on these distinct but related measurements. The correlation was higher in high population density areas. User-generated active transportation data might complement traditional surveillance systems by providing near real-time, location-specific information on where active transportation occurs. PMID:27632357

  13. Association Between User-Generated Commuting Data and Population-Representative Active Commuting Surveillance Data - Four Cities, 2014-2015.

    PubMed

    Whitfield, Geoffrey P; Ussery, Emily N; Riordan, Brian; Wendel, Arthur M

    2016-09-16

    Creating environments that support all types of physical activity, including active transportation, is a public health priority (1). Public health surveillance that identifies the locations where community members walk and bicycle (i.e., engage in active transportation) can inform such efforts. Traditional population-representative active transportation surveillance incurs a considerable time lag between data collection and dissemination, and often lacks geographic specificity (2). Conversely, user-generated active transportation data from Global Positioning System (GPS)-based activity tracking devices and mobile applications can provide near real-time information, but might be subject to self-selection bias among users. CDC analyzed the association between GPS-based commuting data from a company that allows tracking of activity with a mobile application (Strava, Inc., San Francisco, California) and population-representative commuting data from the U.S. Census Bureau's American Community Survey (ACS) (3) for four U.S. cities. The level of analysis was the Census block group. The number of GPS-tracked commuters in Strava was associated with the number of ACS active commuters (Spearman's rho = 0.60), suggesting block groups were ranked similarly based on these distinct but related measurements. The correlation was higher in high population density areas. User-generated active transportation data might complement traditional surveillance systems by providing near real-time, location-specific information on where active transportation occurs.

  14. Associations between bicycling and carotid arterial stiffness in adolescents: The European Youth Hearts Study.

    PubMed

    Ried-Larsen, M; Grøntved, A; Østergaard, L; Cooper, A R; Froberg, K; Andersen, L B; Møller, N C

    2015-10-01

    The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys using their bicycle every day of the week displayed a higher carotid arterial compliance {standard beta 0.47 [95% confidence interval (CI) 0.07-0.87]} and distension [standard beta 0.38 (95% CI -0.04 to 0.81)]. Boys using their bicycle every day of the week furthermore displayed a lower Young's elastic modulus [standard beta -0.48 (95% CI -0.91 to -0.06)]. Similar trends were observed when investigating the association between commuter bicycling and carotid arterial stiffness. These associations were not observed in girls. Our observations suggest that increasing bicycling in adolescence may be beneficial to carotid arterial health among boys.

  15. Associations between bicycling and carotid arterial stiffness in adolescents: The European Youth Hearts Study.

    PubMed

    Ried-Larsen, M; Grøntved, A; Østergaard, L; Cooper, A R; Froberg, K; Andersen, L B; Møller, N C

    2015-10-01

    The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys using their bicycle every day of the week displayed a higher carotid arterial compliance {standard beta 0.47 [95% confidence interval (CI) 0.07-0.87]} and distension [standard beta 0.38 (95% CI -0.04 to 0.81)]. Boys using their bicycle every day of the week furthermore displayed a lower Young's elastic modulus [standard beta -0.48 (95% CI -0.91 to -0.06)]. Similar trends were observed when investigating the association between commuter bicycling and carotid arterial stiffness. These associations were not observed in girls. Our observations suggest that increasing bicycling in adolescence may be beneficial to carotid arterial health among boys. PMID:25156494

  16. Simulation of population-based commuter exposure to NO₂ using different air pollution models.

    PubMed

    Ragettli, Martina S; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C

    2014-05-12

    We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m(-3), range: 21-61) than with a dispersion model with a lower resolution (39 ± 5 µg m(-3); range: 24-51), and a land use regression model (41 ± 5 µg m(-3); range: 24-54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas.

  17. Simulation of Population-Based Commuter Exposure to NO2 Using Different Air Pollution Models

    PubMed Central

    Ragettli, Martina S.; Tsai, Ming-Yi; Braun-Fahrländer, Charlotte; de Nazelle, Audrey; Schindler, Christian; Ineichen, Alex; Ducret-Stich, Regina E.; Perez, Laura; Probst-Hensch, Nicole; Künzli, Nino; Phuleria, Harish C.

    2014-01-01

    We simulated commuter routes and long-term exposure to traffic-related air pollution during commute in a representative population sample in Basel (Switzerland), and evaluated three air pollution models with different spatial resolution for estimating commute exposures to nitrogen dioxide (NO2) as a marker of long-term exposure to traffic-related air pollution. Our approach includes spatially and temporally resolved data on actual commuter routes, travel modes and three air pollution models. Annual mean NO2 commuter exposures were similar between models. However, we found more within-city and within-subject variability in annual mean (±SD) NO2 commuter exposure with a high resolution dispersion model (40 ± 7 µg m−3, range: 21–61) than with a dispersion model with a lower resolution (39 ± 5 µg m−3; range: 24–51), and a land use regression model (41 ± 5 µg m−3; range: 24–54). Highest median cumulative exposures were calculated along motorized transport and bicycle routes, and the lowest for walking. For estimating commuter exposure within a city and being interested also in small-scale variability between roads, a model with a high resolution is recommended. For larger scale epidemiological health assessment studies, models with a coarser spatial resolution are likely sufficient, especially when study areas include suburban and rural areas. PMID:24823664

  18. Probing deformed quantum commutators

    NASA Astrophysics Data System (ADS)

    Rossi, Matteo A. C.; Giani, Tommaso; Paris, Matteo G. A.

    2016-07-01

    Several quantum gravity theories predict a minimal length at the order of magnitude of the Planck length, under which the concepts of space and time lose their physical meaning. In quantum mechanics, the insurgence of such a minimal length can be described by introducing a modified position-momentum commutator, which in turn yields a generalized uncertainty principle, where the uncertainty on position measurements has a lower bound. The value of the minimal length is not predicted by theories and must be estimated experimentally. In this paper, we address the quantum bound to the estimability of the minimal uncertainty length by performing measurements on a harmonic oscillator, which is analytically solvable in the deformed algebra induced by the deformed commutation relations.

  19. [Prevention of bicycle accidents].

    PubMed

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  20. [Prevention of bicycle accidents].

    PubMed

    Zwipp, H; Barthel, P; Bönninger, J; Bürkle, H; Hagemeister, C; Hannawald, L; Huhn, R; Kühn, M; Liers, H; Maier, R; Otte, D; Prokop, G; Seeck, A; Sturm, J; Unger, T

    2015-04-01

    For a very precise analysis of all injured bicyclists in Germany it would be important to have definitions for "severely injured", "seriously injured" and "critically injured". By this, e.g., two-thirds of surgically treated bicyclists who are not registered by the police could become available for a general analysis. Elderly bicyclists (> 60 years) are a minority (10 %) but represent a majority (50 %) of all fatalities. They profit most by wearing a helmet and would be less injured by using special bicycle bags, switching on their hearing aids and following all traffic rules. E-bikes are used more and more (145 % more in 2012 vs. 2011) with 600,000 at the end of 2011 and are increasingly involved in accidents but still have a lack of legislation. So even for pedelecs 45 with 500 W and a possible speed of 45 km/h there is still no legislative demand for the use of a protecting helmet. 96 % of all injured cyclists in Germany had more than 0.5 ‰ alcohol in their blood, 86 % more than 1.1 ‰ and 59 % more than 1.7 ‰. Fatalities are seen in 24.2 % of cases without any collision partner. Therefore the ADFC calls for a limit of 1.1 ‰. Some virtual studies conclude that integrated sensors in bicycle helmets which would interact with sensors in cars could prevent collisions or reduce the severity of injury by stopping the cars automatically. Integrated sensors in cars with opening angles of 180° enable about 93 % of all bicyclists to be detected leading to a high rate of injury avoidance and/or mitigation. Hanging lamps reduce with 35 % significantly bicycle accidents for children, traffic education for children and special trainings for elderly bicyclists are also recommended as prevention tools. As long as helmet use for bicyclists in Germany rates only 9 % on average and legislative orders for using a helmet will not be in force in the near future, coming up campaigns seem to be necessary to be promoted by the Deutscher

  1. Radar channel balancing with commutation

    SciTech Connect

    Doerry, Armin Walter

    2014-02-01

    When multiple channels are employed in a pulse-Doppler radar, achieving and maintaining balance between the channels is problematic. In some circumstances the channels may be commutated to achieve adequate balance. Commutation is the switching, trading, toggling, or multiplexing of the channels between signal paths. Commutation allows modulating the imbalance energy away from the balanced energy in Doppler, where it can be mitigated with filtering.

  2. Exploring bikeability in a metropolitan setting: stimulating and hindering factors in commuting route environments

    PubMed Central

    2012-01-01

    Background Route environments may influence people's active commuting positively and thereby contribute to public health. Assessments of route environments are, however, needed in order to better understand the possible relationship between active commuting and the route environment. The aim of this study was, therefore, to assess the potential associations between perceptions of whether the route environment on the whole hinders or stimulates bicycle commuting and perceptions of environmental factors. Methods The Active Commuting Route Environment Scale (ACRES) was used for the assessment of bicycle commuters' perceptions of their route environments in the inner urban parts of Greater Stockholm, Sweden. Bicycle commuters (n = 827) were recruited by advertisements in newspapers. Simultaneous multiple regression analyses were used to assess the relation between predictor variables (such as levels of exhaust fumes, noise, traffic speed, traffic congestion and greenery) and the outcome variable (hindering - stimulating route environments). Two models were run, (Model 1) without and (Model 2) with the item traffic: unsafe or safe included as a predictor. Results Overall, about 40% of the variance of hindering - stimulating route environments was explained by the environmental predictors in our models (Model 1, R2 = 0.415, and Model 2, R 2= 0.435). The regression equation for Model 1 was: y = 8.53 + 0.33 ugly or beautiful + 0.14 greenery + (-0.14) course of the route + (-0.13) exhaust fumes + (-0.09) congestion: all types of vehicles (p ≤ 0.019). The regression equation for Model 2 was y = 6.55 + 0.31 ugly or beautiful + 0.16 traffic: unsafe or safe + (-0.13) exhaust fumes + 0.12 greenery + (-0.12) course of the route (p ≤ 0.001). Conclusions The main results indicate that beautiful, green and safe route environments seem to be, independently of each other, stimulating factors for bicycle commuting in inner urban areas. On the other hand, exhaust fumes, traffic

  3. Bicyclic glutamic acid derivatives.

    PubMed

    Meyer, Udo; Bisel, Philippe; Weckert, Edgar; Frahm, August Wilhelm

    2006-05-15

    For the second-generation asymmetric synthesis of the trans-tris(homoglutamic) acids via Strecker reaction of chiral ketimines, the cyanide addition as the key stereodifferentiating step produces mixtures of diastereomeric alpha-amino nitrile esters the composition of which is independent of the reaction temperature and the type of the solvent, respectively. The subsequent hydrolysis is exclusively achieved with concentrated H(2)SO(4) yielding diastereomeric mixtures of three secondary alpha-amino alpha-carbamoyl-gamma-esters and two diastereomeric cis-fused angular alpha-carbamoyl gamma-lactams as bicyclic glutamic acid derivatives, gained from in situ stereomer differentiating cyclisation of the secondary cis-alpha-amino alpha-carbamoyl-gamma-esters. Separation was achieved by CC. The pure secondary trans-alpha-amino alpha-carbamoyl-gamma-esters cyclise on heating and treatment with concentrated H(2)SO(4), respectively, to diastereomeric cis-fused angular secondary alpha-amino imides. Their hydrogenolysis led to the enantiomeric cis-fused angular primary alpha-amino imides. The configuration of all compounds was completely established by NMR methods, CD-spectra, and by X-ray analyses of the (alphaR,1R,5R)-1-carbamoyl-2-(1-phenylethyl)-2-azabicyclo[3.3.0]octan-3-one and of the trans-alphaS,1S,2R-2-ethoxycarbonylmethyl-1-(1-phenylethylamino)cyclopentanecarboxamide. PMID:16596563

  4. 36 CFR 1004.30 - Bicycles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... routes between sunset and sunrise without exhibiting on the bicycle or on the operator an activated white... tunnel, or between sunset and sunrise, without exhibiting on the operator or bicycle a white light...

  5. Gravity from a modified commutator

    SciTech Connect

    Jackson, Mark G.; /Fermilab

    2005-05-01

    We show that a suitably chosen position-momentum commutator can elegantly describe many features of gravity, including the IR/UV correspondence and dimensional reduction (''holography''). Using the most simplistic example based on dimensional analysis of black holes, we construct a commutator which qualitatively exhibits these novel properties of gravity. Dimensional reduction occurs because the quanta size grow quickly with momenta, and thus cannot be ''packed together'' as densely as naively expected. We conjecture that a more precise form of this commutator should be able to quantitatively reproduce all of these features.

  6. Bicycle Safety with the Mice Family.

    ERIC Educational Resources Information Center

    Flagg, Jean; Hawkins, Walter

    This 106-page workbook uses a question and answer format to present bicycle safety to students (elementary and/or junior high). The book is extensively illustrated, using a family of mice as characters throughout. Space is provided for students to write responses to questions. Topics covered include history of the bicycle, parts of the bicycle,…

  7. The Fort Collins Commuter Study: Impact of route type and transport mode on personal exposure to multiple air pollutants

    PubMed Central

    Good, Nicholas; Mölter, Anna; Ackerson, Charis; Bachand, Annette; Carpenter, Taylor; Clark, Maggie L; Fedak, Kristen M; Kayne, Ashleigh; Koehler, Kirsten; Moore, Brianna; L'Orange, Christian; Quinn, Casey; Ugave, Viney; Stuart, Amy L; Peel, Jennifer L; Volckens, John

    2016-01-01

    Traffic-related air pollution is associated with increased mortality and morbidity, yet few studies have examined strategies to reduce individual exposure while commuting. The present study aimed to quantify how choice of mode and route type affects personal exposure to air pollutants during commuting. We analyzed within-person difference in exposures to multiple air pollutants (black carbon (BC), carbon monoxide (CO), ultrafine particle number concentration (PNC), and fine particulate matter (PM2.5)) during commutes between the home and workplace for 45 participants. Participants completed 8 days of commuting by car and bicycle on direct and alternative (reduced traffic) routes. Mean within-person exposures to BC, PM2.5, and PNC were higher when commuting by cycling than when driving, but mean CO exposure was lower when cycling. Exposures to CO and BC were reduced when commuting along alternative routes. When cumulative exposure was considered, the benefits from cycling were attenuated, in the case of CO, or exacerbated, in the case of particulate exposures, owing to the increased duration of the commute. Although choice of route can reduce mean exposure, the effect of route length and duration often offsets these reductions when cumulative exposure is considered. Furthermore, increased ventilation rate when cycling may result in a more harmful dose than inhalation at a lower ventilation rate. PMID:26507004

  8. The Fort Collins Commuter Study: Impact of route type and transport mode on personal exposure to multiple air pollutants.

    PubMed

    Good, Nicholas; Mölter, Anna; Ackerson, Charis; Bachand, Annette; Carpenter, Taylor; Clark, Maggie L; Fedak, Kristen M; Kayne, Ashleigh; Koehler, Kirsten; Moore, Brianna; L'Orange, Christian; Quinn, Casey; Ugave, Viney; Stuart, Amy L; Peel, Jennifer L; Volckens, John

    2016-06-01

    Traffic-related air pollution is associated with increased mortality and morbidity, yet few studies have examined strategies to reduce individual exposure while commuting. The present study aimed to quantify how choice of mode and route type affects personal exposure to air pollutants during commuting. We analyzed within-person difference in exposures to multiple air pollutants (black carbon (BC), carbon monoxide (CO), ultrafine particle number concentration (PNC), and fine particulate matter (PM2.5)) during commutes between the home and workplace for 45 participants. Participants completed 8 days of commuting by car and bicycle on direct and alternative (reduced traffic) routes. Mean within-person exposures to BC, PM2.5, and PNC were higher when commuting by cycling than when driving, but mean CO exposure was lower when cycling. Exposures to CO and BC were reduced when commuting along alternative routes. When cumulative exposure was considered, the benefits from cycling were attenuated, in the case of CO, or exacerbated, in the case of particulate exposures, owing to the increased duration of the commute. Although choice of route can reduce mean exposure, the effect of route length and duration often offsets these reductions when cumulative exposure is considered. Furthermore, increased ventilation rate when cycling may result in a more harmful dose than inhalation at a lower ventilation rate. PMID:26507004

  9. The Fort Collins Commuter Study: Impact of route type and transport mode on personal exposure to multiple air pollutants.

    PubMed

    Good, Nicholas; Mölter, Anna; Ackerson, Charis; Bachand, Annette; Carpenter, Taylor; Clark, Maggie L; Fedak, Kristen M; Kayne, Ashleigh; Koehler, Kirsten; Moore, Brianna; L'Orange, Christian; Quinn, Casey; Ugave, Viney; Stuart, Amy L; Peel, Jennifer L; Volckens, John

    2016-06-01

    Traffic-related air pollution is associated with increased mortality and morbidity, yet few studies have examined strategies to reduce individual exposure while commuting. The present study aimed to quantify how choice of mode and route type affects personal exposure to air pollutants during commuting. We analyzed within-person difference in exposures to multiple air pollutants (black carbon (BC), carbon monoxide (CO), ultrafine particle number concentration (PNC), and fine particulate matter (PM2.5)) during commutes between the home and workplace for 45 participants. Participants completed 8 days of commuting by car and bicycle on direct and alternative (reduced traffic) routes. Mean within-person exposures to BC, PM2.5, and PNC were higher when commuting by cycling than when driving, but mean CO exposure was lower when cycling. Exposures to CO and BC were reduced when commuting along alternative routes. When cumulative exposure was considered, the benefits from cycling were attenuated, in the case of CO, or exacerbated, in the case of particulate exposures, owing to the increased duration of the commute. Although choice of route can reduce mean exposure, the effect of route length and duration often offsets these reductions when cumulative exposure is considered. Furthermore, increased ventilation rate when cycling may result in a more harmful dose than inhalation at a lower ventilation rate.

  10. Commuting projections on graphs

    SciTech Connect

    Vassilevski, Panayot S.; Zikatanov, Ludmil T.

    2013-02-19

    For a given (connected) graph, we consider vector spaces of (discrete) functions defined on its vertices and its edges. These two spaces are related by a discrete gradient operator, Grad and its adjoint, ₋Div, referred to as (negative) discrete divergence. We also consider a coarse graph obtained by aggregation of vertices of the original one. Then a coarse vertex space is identified with the subspace of piecewise constant functions over the aggregates. We consider the ℓ2-projection QH onto the space of these piecewise constants. In the present paper, our main result is the construction of a projection π H from the original edge-space onto a properly constructed coarse edge-space associated with the edges of the coarse graph. The projections π H and QH commute with the discrete divergence operator, i.e., we have div π H = QH div. The respective pair of coarse edge-space and coarse vertexspace offer the potential to construct two-level, and by recursion, multilevel methods for the mixed formulation of the graph Laplacian which utilizes the discrete divergence operator. The performance of one two-level method with overlapping Schwarz smoothing and correction based on the constructed coarse spaces for solving such mixed graph Laplacian systems is illustrated on a number of graph examples.

  11. Bicycle Safety: Sport Education Style

    ERIC Educational Resources Information Center

    Sinelnikov, Oleg A.; Hastie, Peter A.; Cole, Amy; Schneulle, Deanna

    2005-01-01

    Although the benefits of regular physical activity are well-documented and very well known, Americans are still becoming more sedentary and obese. As some experts envision the potential of nonmotorized transport in the future, especially in urban settings, it is not surprising that diverse groups view walking and bicycling as a solution to an…

  12. Proper fit of the bicycle.

    PubMed

    Burke, E R

    1994-01-01

    After cyclists have carefully made adjustments for proper fit, minor aches and pains may develop before the body adjusts to the new riding posture. This is normal--so resist the temptation to fiddle with the position much. They will become accustomed to the new riding position after a few rides, and cycling performance will be improved. Then they can concentrate on bike handling skills and fitness confident that their riding position is as good as can be. Proper bicycle fit requires careful review of bicycle selection, saddle height for proper leg extension, fore-and-aft positioning of the knee over the pedal, saddle tilt, handlebar position, and positioning of the upper body for optimum comfort and performance. Further research on the effects of maintaining an aerodynamic position for extended periods of time needs to be investigated to review fatigue patterns in lower and upper body musculature. The underlying principle of positioning a cyclist on a bicycle is to remember that the bicycle is adjustable, and the cyclist is adaptable. PMID:8111846

  13. Car Hits Boy on Bicycle

    ERIC Educational Resources Information Center

    Ruiz, Michael J.

    2005-01-01

    In this article we present the fascinating reconstruction of an accident where a car hit a boy riding his bicycle. The boy dramatically flew several metres through the air after the collision and was injured, but made a swift and complete recovery from the accident with no long-term after-effects. Students are challenged to determine the speed of…

  14. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    PubMed

    Hess, George; Peterson, M Nils

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited. PMID:26317355

  15. "Bicycles May Use Full Lane" Signage Communicates U.S. Roadway Rules and Increases Perception of Safety.

    PubMed

    Hess, George; Peterson, M Nils

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to "get out of the way" to allow motorists to pass without changing lanes: "Bicycles May Use Full Lane" and "Share the Road" signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. "Bicycles May Use Full Lane" signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. "Share the Road" signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. "Bicycles May Use Full Lane" signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing "Share the Road" with "Bicycles May Use Full Lane" signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited.

  16. Bicycles May Use Full Lane” Signage Communicates U.S. Roadway Rules and Increases Perception of Safety

    PubMed Central

    2015-01-01

    Many global challenges, including obesity, health care costs, and climate change, could be addressed in part by increasing the use of bicycles for transportation. Concern about the safety of bicycling on roadways is frequently cited as a deterrent to increasing bicycle use in the USA. The use of effective signage along roadways might help alleviate these concerns by increasing knowledge about the rights and duties of bicyclists and motorists, ideally reducing crashes. We administered a web-based survey, using Twitter for recruitment, to examine how well three US traffic control devices communicated the message that bicyclists are permitted in the center of the travel lane and do not have to “get out of the way” to allow motorists to pass without changing lanes: “Bicycles May Use Full Lane” and “Share the Road” signage, and Shared Lane Markings on the pavement. Each was compared to an unsigned roadway. We also asked respondents whether it was safe for a bicyclist to occupy the center of the travel lane. “Bicycles May Use Full Lane” signage was the most consistently comprehended device for communicating the message that bicyclists may occupy the travel lane and also increased perceptions of safety. “Share the Road” signage did not increase comprehension or perceptions of safety. Shared Lane Markings fell somewhere between. “Bicycles May Use Full Lane” signage showed notable increases in comprehension among novice bicyclists and private motor vehicle commuters, critical target audiences for efforts to promote bicycling in the USA. Although limited in scope, our survey results are indicative and suggest that Departments of Transportation consider replacing “Share the Road” with “Bicycles May Use Full Lane” signage, possibly combined with Shared Lane Markings, if the intent is to increase awareness of roadway rights and responsibilities. Further evaluation through virtual reality simulations and on-road experiments is merited. PMID

  17. Macroscopic modeling of pedestrian and bicycle crashes: A cross-comparison of estimation methods.

    PubMed

    Amoh-Gyimah, Richard; Saberi, Meead; Sarvi, Majid

    2016-08-01

    The paper presents a cross-comparison of different estimation methods to model pedestrian and bicycle crashes. The study contributes to macro level safety studies by providing further methodological and empirical evidence on the various factors that influence the frequency of pedestrian and bicycle crashes at the planning level. Random parameter negative binomial (RPNB) models are estimated to explore the effects of various planning factors associated with total, serious injury and minor injury crashes while accounting for unobserved heterogeneity. Results of the RPNB models were compared with the results of a non-spatial negative binomial (NB) model and a Poisson-Gamma-CAR model. Key findings are, (1) the RPNB model performed best with the lowest mean absolute deviation, mean squared predicted error and Akaiki information criterion measures and (2) signs of estimated parameters are consistent if these variables are significant in models with the same response variables. We found that vehicle kilometers traveled (VKT), population, percentage of commuters cycling or walking to work, and percentage of households without motor vehicles have a significant and positive correlation with the number of pedestrian and bicycle crashes. Mixed land use is also found to have a positive association with the number of pedestrian and bicycle crashes. Results have planning and policy implications aimed at encouraging the use of sustainable modes of transportation while ensuring the safety of pedestrians and cyclist. PMID:27209153

  18. Orientation to Bicycles: Training Course No. T34 Workbook.

    ERIC Educational Resources Information Center

    Consumer Product Safety Commission, Washington, DC.

    The workbook is intended to provide personnel having responsibility for bicycle investigations or inspections with an overview and technical information on bicycles which will serve as a technical foundation for understanding the bicycle regulations. It discusses bicycles in general, and introduces the user to the specific parts of bicycles. On…

  19. Steering in bicycles and motorcycles

    NASA Astrophysics Data System (ADS)

    Fajans, J.

    2000-07-01

    Steering a motorcycle or bicycle is counterintuitive; to turn right, you must steer left initially, and vice versa. You can execute this initially counter-directed turn by turning the handlebars explicitly (called counter-steering) or by throwing your hips to the side. Contrary to common belief, gyroscopic forces play only a limited role in balancing and steering [D. E. H. Jones, Phys. Today 23 (4), 34-40 (1970)].

  20. Electric-bicycle propulsion power

    SciTech Connect

    Oman, H.; Morchin, W.C.; Jamerson, F.E.

    1995-12-31

    In a human-powered hybrid electric vehicle (HPHEV) the travel distance available from a single battery charge can be lengthened with power from another source, the cyclist`s leg muscles. In a battery-powered electric bicycle the propulsion power goes mostly into overcoming aerodynamic drag. For example, at 18 km per hour (11 miles per hour) this drag represents 200 watts at the tire-to-road interface for a typical cyclist`s shape and clothing. Today`s typical electrical bicycle is propelled by a high-speed dc motor which is powered from a lead-acid battery. The combined efficiency of the motor and its speed-reducing gears is 50 to 65 percent. In this paper we calculate available travel distances, as a function of speed, grade, and the battery energy-content as measured in watt-hours per kg. We show the effect of battery cost and charge/discharge cycle-life on travel cost in terms of cents per kilometer travelled. Designs used in today`s electric bicycles are illustrated.

  1. Electromagnetic Gun With Commutated Coils

    NASA Technical Reports Server (NTRS)

    Elliott, David G.

    1991-01-01

    Proposed electromagnetic gun includes electromagnet coil, turns of which commutated in sequence along barrel. Electrical current fed to two armatures by brushes sliding on bus bars in barrel. Interaction between armature currents and magnetic field from coil produces force accelerating armature, which in turn, pushes on projectile. Commutation scheme chosen so magnetic field approximately coincides and moves with cylindrical region defined by armatures. Scheme has disadvantage of complexity, but in return, enables designer to increase driving magnetic field without increasing armature current. Attainable muzzle velocity increased substantially.

  2. Identification of the mechanical properties of bicycle tyres for modelling of bicycle dynamics

    NASA Astrophysics Data System (ADS)

    Doria, Alberto; Tognazzo, Mauro; Cusimano, Gianmaria; Bulsink, Vera; Cooke, Adrian; Koopman, Bart

    2013-03-01

    Advanced simulation of the stability and handling properties of bicycles requires detailed road-tyre contact models. In order to develop these models, in this study, four bicycle tyres are tested by means of a rotating disc machine with the aim of measuring the components of tyre forces and torques that influence the safety and handling of bicycles. The effect of inflation pressure and tyre load is analysed. The measured properties of bicycle tyres are compared with those of motorcycle tyres.

  3. Commuting Patterns of Nonmetro Household Heads, 1975.

    ERIC Educational Resources Information Center

    Bowles, Gladys K.; Beale, Calvin L.

    Data from the Annual Housing Survey indicated that 22% of all employed United States household heads commuted to a county different from that in which they lived in 1975. Commuting was more prevalent among men than among women and slightly higher for whites than for Blacks. Commuting tended to increase until age 25-34 and then to decline after age…

  4. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the...

  5. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the...

  6. 45 CFR 3.27 - Bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Bicycles. 3.27 Section 3.27 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.27 Bicycles. A person may not operate a...

  7. 45 CFR 3.27 - Bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 1 2011-10-01 2011-10-01 false Bicycles. 3.27 Section 3.27 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.27 Bicycles. A person may not operate a...

  8. 45 CFR 3.27 - Bicycles.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 1 2014-10-01 2014-10-01 false Bicycles. 3.27 Section 3.27 Public Welfare Department of Health and Human Services GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.27 Bicycles. A person may not operate a...

  9. 45 CFR 3.27 - Bicycles.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Bicycles. 3.27 Section 3.27 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.27 Bicycles. A person may not operate a...

  10. 45 CFR 3.27 - Bicycles.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 1 2013-10-01 2013-10-01 false Bicycles. 3.27 Section 3.27 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE Traffic Regulations § 3.27 Bicycles. A person may not operate a...

  11. The Bicycle: A Great Vehicle for Learning

    ERIC Educational Resources Information Center

    Kraft, Thomas E.

    2005-01-01

    A person's first significant "hands-on" encounter with mechanical things during childhood often comes through use of a bicycle. Almost all of us have personal experience with this element of transportation technology. Educators can use the bicycle to address a variety of standards that involve tool use, mechanics, science, math, and the interplay…

  12. Good Practices Guide for Bicycle Safety Education.

    ERIC Educational Resources Information Center

    Department of Transportation, Washington, DC.

    The purpose of this guide is to serve as an informational resource for educators and other interested professionals in planning and developing bicycle safety education programs. The guide examines 15 existing bicycle safety education programs in the United States and one from Canada. (Author)

  13. Stabilizing a Bicycle: A Modeling Project

    ERIC Educational Resources Information Center

    Pennings, Timothy J.; Williams, Blair R.

    2010-01-01

    This article is a project that takes students through the process of forming a mathematical model of bicycle dynamics. Beginning with basic ideas from Newtonian mechanics (forces and torques), students use techniques from calculus and differential equations to develop the equations of rotational motion for a bicycle-rider system as it tips from…

  14. 36 CFR 1004.30 - Bicycles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... places convenient to the public. (2) Bicycle speed limits are as follows: (i) 15 miles per hour: Upon all... light that is visible from a distance of at least 500 feet to the front and with a red light or... tunnel, or between sunset and sunrise, without exhibiting on the operator or bicycle a white light...

  15. 75 FR 67043 - Requirements for Bicycles

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... bicycles until August 14, 2010, with two exceptions (75 FR 34360). First, because laboratory capacity, at... bicycles pursuant to the Federal Hazardous Substances Act. The regulations were first promulgated in 1978 (43 FR 60034 (Dec. 22, 1978)), with minor amendments in 1980 (45 FR 82627 (Dec. 16, 1980)), 1981...

  16. Bicycle helmet use and bicycling-related injury among young Canadians: an equity analysis

    PubMed Central

    2013-01-01

    Introduction Cycling is a major activity for adolescents in Canada and potential differences exist in bicycling-related risk and experience of injury by population subgroup. The overall aim of this study was to inform health equity interventions by profiling stratified analytic methods and identifying potential inequities associated with bicycle-related injury and the use of bicycle helmets among Canadian youth. The two objectives of this study were: (1) To examine national patterns in bicycle ridership and also bicycle helmet use among Canadian youth in a stratified analysis by potentially vulnerable population subgroups, and (2) To examine bicycling-related injury in the same population subgroups of Canadian youth in order to identify possible health inequities. Methods Data for this study were obtained from the 6th cycle (2009/10) of the Health Behaviour in School-aged Children (HBSC) study, which is a general health survey that was completed by 26,078 students in grades 6–10 from 436 Canadian schools. Based on survey responses, we determined point prevalence for bicycle ridership, bicycle helmet use and relative risks for bicycling-related injury. Results Three quarters of all respondents were bicycle riders (n=19,410). Independent factors associated with bicycle ridership among students include being male, being a younger student, being more affluent, and being a resident of a small town. Among bicycle riders, 43% (95%CI ± 0.6%) reported never wearing and 32% (± 0.6%) inconsistently wearing a helmet. Only 26% (± 0.5%) of students reported always wearing a bicycle helmet. Helmets were less frequently used among older students and there were also important patterns by sex, geographic location and socioeconomic status. Adjusting for all other demographic characteristics, boys reported 2.02-fold increase (95% CI: 1.61 to 1.90) and new immigrants a 1.35-fold increase (95%CI: 1.00 to1.82) in the relative risk of bicycling-related injury in the past 12 months

  17. Asymmetry in bicycle ergometer pedalling.

    PubMed

    Daly, D J; Cavanagh, P R

    1976-01-01

    The effects of changes in speed and resistance setting on the bilateral symmetry of work output on the bicycle ergometer were studied. The cranks of a Monarch bicycle ergometer were instrumented with foil strain gauges and the bridge outputs were integrated on-line and analyzed by a program running in a Hewlett Packard 2115A computer. Twenty male subjects performed three thirty-second trials at each of nine speed and resistance combinations. Indices of asymmetry from 66-178 were found using kicking dominance (n = 20) and 56-135 using a strength dominance classification (n = 13). Day to day reliability of the index of asymmetry was found to be only 0.47; within day reliability was 0.87 for day one and 0.79 for day two. No significant effects for speed or resistance changes were shown on either day for the strength dominant subjects. When kicking dominance was considered main effects were encountered on both days for speed although there was no clear directional trend. The findings of these experiments have important implications for studies where measurements are made on the lower extremity during cycle ergometer exercise, and for competitive cyclists engaged in endurance competition.

  18. Johnson Space Center's Free Range Bicycle Program.- Fall 2015 Intern Report

    NASA Technical Reports Server (NTRS)

    Lee-Stockton, Willem

    2015-01-01

    NASA's Johnson Space Center is a big place, encompassing 1,620 acres and more than a hundred buildings. Furthermore, there are reportedly 15 thousand employees, all of which have somewhere to be. To facilitate the movement of all these people JSC has historically relied on human power. Pedaling their way towards deep space, bicycles have been the go to method. Currently there are about 200 Free Range Bicycles at JSC. Free Range Bicycles belong to nobody, except NASA, and are available for anybody to use. They are not to be locked or hidden (although frequently are) and the intention is that there will always be a bike to hop on to get where you're going (although it may not be the bike you rode in on). Although not without its own shortcomings, the Free Range Bicycle Program has continued to provide low cost, simple transportation for NASA's JSC. In addition to the approximately 200 Free Range Bicycles, various larger divisions (like engineering) will often buy a few dozen bikes for their team members to use or individuals will bring their own personal bike to either commute or use on site. When these bicycles fall into disrepair or are abandoned (from retirees etc) they become a problem at JSC. They are an eye sore, create a safety hazard and make it harder to find a working bike in a time of need. The Free Range Program hopes to address this first problem by "tagging out" abandoned or out of service bicycles. A bright orange "DO NOT OPERATE" tag is placed on the bike and given a serial number for tracking purposes. See picture to the right. If the bike has an active owner with intentions to repair the bike the bottom of the tag has instructions for how to claim the abandoned bicycle. After being tagged the owner of the bicycle has 30 days to claim the bicycle and either haul it off site or get it repaired (and labeled) in accordance with Johnson's Bicycle Policy. If the abandoned bicycle is not claimed within 30 days it becomes the property of the Government. The

  19. Street lighting disturbs commuting bats.

    PubMed

    Stone, Emma Louise; Jones, Gareth; Harris, Stephen

    2009-07-14

    Anthropogenic disturbance is a major cause of worldwide declines in biodiversity. Understanding the implications of this disturbance for species and populations is crucial for conservation biologists wishing to mitigate negative effects. Anthropogenic light pollution is an increasing global problem, affecting ecological interactions across a range of taxa and impacting negatively upon critical animal behaviors including foraging, reproduction, and communication (for review see). Almost all bats are nocturnal, making them ideal subjects for testing the effects of light pollution. Previous studies have shown that bat species adapted to foraging in open environments feed on insects attracted to mercury vapor lamps. Here, we use an experimental approach to provide the first evidence of a negative effect of artificial light pollution on the commuting behavior of a threatened bat species. We installed high-pressure sodium lights that mimic the intensity and light spectra of streetlights along commuting routes of lesser horseshoe bats (Rhinolophus hipposideros). Bat activity was reduced dramatically and the onset of commuting behavior was delayed in the presence of lighting, with no evidence of habituation. These results demonstrate that light pollution may have significant negative impacts upon the selection of flight routes by bats. PMID:19540116

  20. Happiness and Satisfaction with Work Commute.

    PubMed

    Olsson, Lars E; Gärling, Tommy; Ettema, Dick; Friman, Margareta; Fujii, Satoshi

    2013-03-01

    Research suggests that for many people happiness is being able to make the routines of everyday life work, such that positive feelings dominate over negative feelings resulting from daily hassles. In line with this, a survey of work commuters in the three largest urban areas of Sweden show that satisfaction with the work commute contributes to overall happiness. It is also found that feelings during the commutes are predominantly positive or neutral. Possible explanatory factors include desirable physical exercise from walking and biking, as well as that short commutes provide a buffer between the work and private spheres. For longer work commutes, social and entertainment activities either increase positive affects or counteract stress and boredom. Satisfaction with being employed in a recession may also spill over to positive experiences of work commutes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11205-012-0003-2) contains supplementary material, which is available to authorized users.

  1. The effects of sign design features on bicycle pictorial symbols for bicycling facility signs.

    PubMed

    Oh, Kyunghui; Rogoff, Aaron; Smith-Jackson, Tonya

    2013-11-01

    The inanimate bicycle symbol has long been used to indicate the animate activity of bicycling facility signs. In contrast, either the inanimate bicycle symbol or the animate bicycle symbol has been used interchangeably for the standard pavement symbols in bike lanes. This has led to confusion among pedestrians and cyclists alike. The purpose of this study was to examine two different designs (inanimate symbol vs. animate symbol) involved in the evaluation of perceived preference and glance legibility, and investigate sign design features on bicycle pictorial symbols. Thirty-five participants compared current bicycle signs (inanimate symbols) to alternative designs (animate symbols) in a controlled laboratory setting. The results indicated that the alternative designs (animate symbols) showed better performance in both preference and glance legibility tests. Conceptual compatibility, familiarity, and perceptual affordances were found to be important factors as well.

  2. Creating a comprehensive bicycle safety program.

    PubMed

    Elwell, Sean; Kulp, Heather; McCue, Jennifer

    2014-01-01

    Trauma centers must play a role in injury prevention. Pediatric trauma centers have the ability to create injury prevention programs targeting all children. After analyzing our trauma registry data, we determined that bicycle injuries are a significant mechanism of injury in children and developed strategies aimed at preventing such injuries. Along with support from Kohl's Cares, we are able to achieve our mission of keeping children in our community healthy and safe. Our comprehensive bicycle safety program is targeted to various ages and learning styles and aims to increase bicycle safety and helmet use among children in our region.

  3. An Assessment of Commuter Aircraft Noise Impact

    NASA Technical Reports Server (NTRS)

    Fidell, Sanford; Pearsons, Karl S.; Silvati, Laura; Sneddon, Matthew

    1996-01-01

    This report examines several approaches to understanding 'the commuter aircraft noise problem.' The commuter aircraft noise problem in the sense addressed in this report is the belief that some aspect(s) of community response to noise produced by commuter aircraft operations may not be fully assessed by conventional environmental noise metrics and methods. The report offers alternate perspectives and approaches for understanding this issue. The report also develops a set of diagnostic screening questions; describes commuter aircraft noise situations at several airports; and makes recommendations for increasing understanding of the practical consequences of greater heterogeneity in the air transport fleet serving larger airports.

  4. Imprecise probability for non-commuting observables

    NASA Astrophysics Data System (ADS)

    Allahverdyan, Armen E.

    2015-08-01

    It is known that non-commuting observables in quantum mechanics do not have joint probability. This statement refers to the precise (additive) probability model. I show that the joint distribution of any non-commuting pair of variables can be quantified via upper and lower probabilities, i.e. the joint probability is described by an interval instead of a number (imprecise probability). I propose transparent axioms from which the upper and lower probability operators follow. The imprecise probability depend on the non-commuting observables, is linear over the state (density matrix) and reverts to the usual expression for commuting observables.

  5. Commutation circuit for an HVDC circuit breaker

    DOEpatents

    Premerlani, W.J.

    1981-11-10

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components. 13 figs.

  6. Commutation circuit for an HVDC circuit breaker

    DOEpatents

    Premerlani, William J.

    1981-01-01

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.

  7. Doing Mathematics with Bicycle Gear Ratios.

    ERIC Educational Resources Information Center

    Stump, Sheryl L.

    2000-01-01

    Describes an activity in which students examine bicycle chain-rings, cogs, and gear ratios as a means of exploring algebraic relationships, data collection, scatter plots, and lines of best fit. (KHR)

  8. 36 CFR 4.30 - Bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sunrise, without exhibiting on the operator or bicycle a white light or reflector that is visible from a distance of at least 500 feet to the front and with a red light or reflector visible from at least 200...

  9. 36 CFR 4.30 - Bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sunrise, without exhibiting on the operator or bicycle a white light or reflector that is visible from a distance of at least 500 feet to the front and with a red light or reflector visible from at least 200...

  10. Commutated automatic gain control system

    NASA Technical Reports Server (NTRS)

    Yost, S. R.

    1982-01-01

    A commutated automatic gain control (AGC) system was designed and built for a prototype Loran C receiver. The receiver uses a microcomputer to control a memory aided phase-locked loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The circuit designed for the AGC is described, and bench and flight test results are presented. The AGC circuit described actually samples starting at a point 40 microseconds after a zero crossing determined by the software lock pulse ultimately generated by a 30 microsecond delay and add network in the receiver front end envelope detector.

  11. On the wobble mode of a bicycle

    NASA Astrophysics Data System (ADS)

    Plöchl, Manfred; Edelmann, Johannes; Angrosch, Bernhard; Ott, Christoph

    2012-03-01

    Wheel shimmy and wobble are well-known dynamic phenomena at automobiles, aeroplanes and motorcycles. In particular, wobble at the motorcycle is an (unstable) eigenmode with oscillations of the wheel about the steering axis, and it is no surprise that unstable bicycle wobble is perceived unpleasant or may be dangerous, if not controlled by the rider in time. Basic research on wobble at motorcycles within the last decades has revealed a better understanding of the sudden onset of wobble, and the complex relations between parameters affecting wobble have been identified. These fundamental findings have been transferred to bicycles. As mass distribution and inertial properties, rider influence and lateral compliances of tyre and frame differ at bicycle and motorcycle, models to represent wobble at motorcycles have to prove themselves, when applied to bicycles. For that purpose numerical results are compared with measurements from test runs, and parametric influences on the stability of the wobble mode at bicycles have been evolved. All numerical analysis and measurements are based on a specific test bicycle equipped with steering angle sensor, wheel-speed sensor, global positioning system (GPS) 3-axis accelerometer, and 3-axis angular velocity gyroscopic sensor.

  12. Is the three-foot bicycle passing law working in Baltimore, Maryland?

    PubMed

    Love, David C; Breaud, Autumn; Burns, Sean; Margulies, Jared; Romano, Max; Lawrence, Robert

    2012-09-01

    Maryland (MD) recently became one of fourteen states in the United States to enact a traffic law requiring motor vehicles to pass bicyclists at a distance of greater than three feet. To our knowledge, motorist compliance with the law has never been assessed. This study measured the distance between overtaking motor vehicles and cyclists [e.g. vehicle passing distance (VPD)], to develop baseline metrics for tracking implementation of the three-foot passing law in Baltimore, MD and to assess risk factors for dangerous passes. During September and October 2011, cyclists (n=5) measured VPD using a previously published video technique (Parkin and Meyers, 2010). Cyclists logged a total of 10.8h of video footage and 586 vehicle passes on 34 bicycle commuting trips. The average trip lasted 19.5±4.9 min and cyclists were passed on average 17.2±11.8 times per trip. VPDs of three feet or less were common when cycling in standard lanes (17%; 78 of 451 passes) and lanes with a shared lane marking (e.g. sharrows) (23%; 11 of 47 passes). No passes of three feet or less occurred in bicycle lanes (0 of 88 passes). A multiple linear regression model was created, which explained 26% of the variability in VPD. Significant model variables were lane width, bicycle infrastructure, cyclist identity, and street identity. Interventions, such as driver education, signage, enforcement, and bicycle infrastructure changes are needed to influence driving behavior in Baltimore to increase motorist compliance with the three-foot law. PMID:22664711

  13. Tsirelson's problem and asymptotically commuting unitary matrices

    SciTech Connect

    Ozawa, Narutaka

    2013-03-15

    In this paper, we consider quantum correlations of bipartite systems having a slight interaction, and reinterpret Tsirelson's problem (and hence Kirchberg's and Connes's conjectures) in terms of finite-dimensional asymptotically commuting positive operator valued measures. We also consider the systems of asymptotically commuting unitary matrices and formulate the Stronger Kirchberg Conjecture.

  14. Happiness and Satisfaction with Work Commute

    ERIC Educational Resources Information Center

    Olsson, Lars E.; Garling, Tommy; Ettema, Dick; Friman, Margareta; Fujii, Satoshi

    2013-01-01

    Research suggests that for many people happiness is being able to make the routines of everyday life work, such that positive feelings dominate over negative feelings resulting from daily hassles. In line with this, a survey of work commuters in the three largest urban areas of Sweden show that satisfaction with the work commute contributes to…

  15. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  16. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  17. 8 CFR 211.5 - Alien commuters.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... shall be made in accordance with 8 CFR 264.5. ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent...

  18. Commutated automatic gain control system

    NASA Technical Reports Server (NTRS)

    Yost, S. R.

    1981-01-01

    A commutated automatic gain control system (AGC) was designed and constructed for the prototype Loran C receiver. The AGC is designed to improve the signal-to-signal ratio of the received Loran signals. The AGC design does not require any analog to digital conversion and it utilizes commonly available components. The AGC consists of: (1) a circuit which samples the peak of the envelope of the Loran signal to obtain an AGC voltage for each of three Loran stations, (2) a dc gain circuit to control the overall gain of the AGC system, and (3) an AGC amplification of the input RF signal. The performance of the AGC system was observed in bench and flight tests; it has improved the overall accuracy of the receiver. Improvements in the accuracy of the time difference calculations to within approx. + or - 1.5 microseconds of the observed time differnces for a given position are reported.

  19. Public Bicycle Share Programs and Head Injuries

    PubMed Central

    Pless, Barry; Moore, Lynne; Nathens, Avery B.; Hunte, Garth; Rivara, Frederick P.

    2014-01-01

    Objectives. We evaluated the effect of North American public bicycle share programs (PBSPs), which typically do not offer helmets with rentals, on the occurrence of bicycle-related head injuries. Methods. We analyzed trauma center data for bicycle-related injuries from 5 cities with PBSPs and 5 comparison cities. We used logistic regression models to compare the odds that admission for a bicycle-related injury would involve a head injury 24 months before PBSP implementation and 12 months afterward. Results. In PBSP cities, the proportion of head injuries among bicycle-related injuries increased from 42.3% before PBSP implementation to 50.1% after (P < .01). This proportion in comparison cities remained similar before (38.2%) and after (35.9%) implementation (P = .23). Odds ratios for head injury were 1.30 (95% confidence interval = 1.13, 1.67) in PBSP cities and 0.94 (95% confidence interval = 0.79, 1.11) in control cities (adjusted for age and city) when we compared the period after implementation to the period before. Conclusions. Results suggest that steps should be taken to make helmets available with PBSPs. Helmet availability should be incorporated into PBSP planning and funding, not considered an afterthought following implementation. PMID:24922150

  20. Fostering Formal Commutativity Knowledge with Approximate Arithmetic.

    PubMed

    Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A; Gaschler, Robert

    2015-01-01

    How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311

  1. Fostering Formal Commutativity Knowledge with Approximate Arithmetic

    PubMed Central

    Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A.; Gaschler, Robert

    2015-01-01

    How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311

  2. Bicycling for transportation and health: the role of infrastructure.

    PubMed

    Dill, Jennifer

    2009-01-01

    This paper aims to provide insight on whether bicycling for everyday travel can help US adults meet the recommended levels of physical activity and what role public infrastructure may play in encouraging this activity. The study collected data on bicycling behavior from 166 regular cyclists in the Portland, Oregon metropolitan area using global positioning system (GPS) devices. Sixty percent of the cyclists rode for more than 150 minutes per week during the study and nearly all of the bicycling was for utilitarian purposes, not exercise. A disproportionate share of the bicycling occurred on streets with bicycle lanes, separate paths, or bicycle boulevards. The data support the need for well-connected neighborhood streets and a network of bicycle-specific infrastructure to encourage more bicycling among adults. This can be accomplished through comprehensive planning, regulation, and funding. PMID:19190585

  3. Bicycling for transportation and health: the role of infrastructure.

    PubMed

    Dill, Jennifer

    2009-01-01

    This paper aims to provide insight on whether bicycling for everyday travel can help US adults meet the recommended levels of physical activity and what role public infrastructure may play in encouraging this activity. The study collected data on bicycling behavior from 166 regular cyclists in the Portland, Oregon metropolitan area using global positioning system (GPS) devices. Sixty percent of the cyclists rode for more than 150 minutes per week during the study and nearly all of the bicycling was for utilitarian purposes, not exercise. A disproportionate share of the bicycling occurred on streets with bicycle lanes, separate paths, or bicycle boulevards. The data support the need for well-connected neighborhood streets and a network of bicycle-specific infrastructure to encourage more bicycling among adults. This can be accomplished through comprehensive planning, regulation, and funding.

  4. Bicycle helmet promotion programs--Canada, Australia, and United States.

    PubMed

    1993-03-26

    The use of bicycle helmets substantially reduces the risk for serious head injuries during bicycle-related crashes. Despite this benefit, epidemiologic data indicate a worldwide low prevalence of helmet use. Strategies to increase the use of bicycle helmets in the United States and other countries include subsidies, legislation, and education. This report summarizes information regarding three strategies to increase bicycle helmet use and the impact of implementing these approaches in Canada (helmet subsidies), Australia (legislation), and the United States (education). PMID:8446097

  5. Database improvements for motor vehicle/bicycle crash analysis

    PubMed Central

    Lusk, Anne C; Asgarzadeh, Morteza; Farvid, Maryam S

    2015-01-01

    Background Bicycling is healthy but needs to be safer for more to bike. Police crash templates are designed for reporting crashes between motor vehicles, but not between vehicles/bicycles. If written/drawn bicycle-crash-scene details exist, these are not entered into spreadsheets. Objective To assess which bicycle-crash-scene data might be added to spreadsheets for analysis. Methods Police crash templates from 50 states were analysed. Reports for 3350 motor vehicle/bicycle crashes (2011) were obtained for the New York City area and 300 cases selected (with drawings and on roads with sharrows, bike lanes, cycle tracks and no bike provisions). Crashes were redrawn and new bicycle-crash-scene details were coded and entered into the existing spreadsheet. The association between severity of injuries and bicycle-crash-scene codes was evaluated using multiple logistic regression. Results Police templates only consistently include pedal-cyclist and helmet. Bicycle-crash-scene coded variables for templates could include: 4 bicycle environments, 18 vehicle impact-points (opened-doors and mirrors), 4 bicycle impact-points, motor vehicle/bicycle crash patterns, in/out of the bicycle environment and bike/relevant motor vehicle categories. A test of including these variables suggested that, with bicyclists who had minor injuries as the control group, bicyclists on roads with bike lanes riding outside the lane had lower likelihood of severe injuries (OR, 0.40, 95% CI 0.16 to 0.98) compared with bicyclists riding on roads without bicycle facilities. Conclusions Police templates should include additional bicycle-crash-scene codes for entry into spreadsheets. Crash analysis, including with big data, could then be conducted on bicycle environments, motor vehicle potential impact points/doors/mirrors, bicycle potential impact points, motor vehicle characteristics, location and injury. PMID:25835304

  6. Are GIS-modelled routes a useful proxy for the actual routes followed by commuters?

    PubMed Central

    Dalton, Alice M; Jones, Andrew P; Panter, Jenna; Ogilvie, David

    2015-01-01

    Active commuting offers the potential to increase physical activity among adults by being built into daily routines. Characteristics of the route to work may influence propensity to walk or cycle. Geographic information system (GIS) software is often used to explore this by modelling routes between home and work. However, if the validity of modelled routes depends on the mode of travel used, studies of environmental determinants of travel may be biased. We aimed to understand how well modelled routes reflect those actually taken, and what characteristics explain these differences. We compared modelled GIS shortest path routes with actual routes measured using QStarz BT-Q1000X Global Positioning System (GPS) devices in a free-living sample of adults working in Cambridge and using varying travel modes. Predictors of differences, according to length and percentage overlap, between the two route sets were assessed using multilevel regression models and concordance coefficients. The 276 trips, made by 51 participants, were on average 27% further than modelled routes, with an average geographical overlap of 39%. However, predictability of the route depended on travel mode. For route length, there was moderate-to-substantial agreement for journeys made on foot and by bicycle. Route overlap was lowest for trips made by car plus walk (22%). The magnitude of difference depended on other journey characteristics, including travelling via intermediate destinations, distance, and use of busy roads. In conclusion, GIS routes may be acceptable for distance estimation and to explore potential routes, particularly active commuting. However, GPS should be used to obtain accurate estimates of environmental contexts in which commuting behaviour actually occurs. Public health researchers should bear these considerations in mind when studying the geographical determinants and health implications of commuting behaviour, and when recommending policy changes to encourage active travel. PMID

  7. Bicycle Safety, Grades K-6. Experimental Curriculum Bulletin.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.

    This experimental curriculum guide for bicycle safety begins with a chapter listing vehicle and traffic laws pertaining to bicycling. Chapter 2 of the guide is organized by grade level. Appropriate lesson plans for bicycle safety are presented with aims, concepts activities and behavioral objectives. A 24-item list of activities summarizes these…

  8. An Analysis of Florida Physical Educators' Knowledge of Bicycle Laws

    ERIC Educational Resources Information Center

    Connaughton, Daniel P.; Egberts, John B.; Spengler, J. O.; Zhang, James J.; Jin, Liyan

    2012-01-01

    Bicycling among youth is a popular activity, but like all modes of travel it is not without risk. Florida has a particularly high rate of bicycle-related fatalities and injuries. To reduce such risks, the Florida Department of Transportation and Florida Department of Education have developed a youth bicycle safety educational program (Florida…

  9. 32 CFR 636.27 - Regulations for bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort Stewart, Georgia... bicycles. Bicycle riders are granted all the rights and are subject to all duties of motorized vehicle operators, except those which logically do not apply. (c) Bicycles will be parked against the curb or in...

  10. 32 CFR 636.27 - Regulations for bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort Stewart, Georgia... bicycles. Bicycle riders are granted all the rights and are subject to all duties of motorized vehicle operators, except those which logically do not apply. (c) Bicycles will be parked against the curb or in...

  11. A Bicycle Safety Education Program for Parents of Young Children

    ERIC Educational Resources Information Center

    Lohse, Julie L.

    2003-01-01

    This study examined parental perceptions of the benefits and barriers to bicycle helmet use and their level of knowledge about bicycle safety issues. A school-based bicycle safety education program was taught to first- and second-grade students in a rural/suburban school district by a graduate nursing student. Pender's Health Promotion Model was…

  12. On the Stability of a Bicycle on Rollers

    ERIC Educational Resources Information Center

    Cleary, Patricia A.; Mohazzabi, Pirooz

    2011-01-01

    Riding a bicycle on the newest form of indoor training, rollers, presents a unique experiment on bicycle stability. The stability factors eliminated by riding on rollers are discussed in terms of refined handling and control of the centre of mass on a bicycle. This paper is intended for undergraduate physics majors as well as any other general…

  13. Planning for rotorcraft and commuter air transportationn

    NASA Technical Reports Server (NTRS)

    Stockwell, W. L.; Stowers, J.

    1981-01-01

    Community planning needs, criteria, and other considerations such as intermodal coordination and regulatory requirements, for rotorcraft and fixed wing commuter air transportation were identified. A broad range of community planning guidelines, issues, and information which can be used to: (1) direct anticipated aircraft technological improvements; (2) assist planners in identifying and evaluating the opportunities and tradeoffs presented by rotorcraft and commuter aircraft options relative to other modes; and (3) increase communication between aircraft technologists and planners for the purpose of on going support in capitalizing on rotorcraft and commuter air opportunities are provided. The primary tool for identifying and analyzing planning requirements was a detailed questionnaire administered to a selected sample of 55 community planners and other involved in planning for helicopters and commuter aviation.

  14. Non-commutativity measure of quantum discord

    NASA Astrophysics Data System (ADS)

    Guo, Yu

    2016-04-01

    Quantum discord is a manifestation of quantum correlations due to non-commutativity rather than entanglement. Two measures of quantum discord by the amount of non-commutativity via the trace norm and the Hilbert-Schmidt norm respectively are proposed in this paper. These two measures can be calculated easily for any state with arbitrary dimension. It is shown by several examples that these measures can reflect the amount of the original quantum discord.

  15. Extreme commutative quantum observables are sharp

    NASA Astrophysics Data System (ADS)

    Heinosaari, Teiko; Pellonpää, Juha-Pekka

    2011-08-01

    It is well known that, in the description of quantum observables, positive operator valued measures (POVMs) generalize projection valued measures (PVMs) and they also turn out be more optimal in many tasks. We show that a commutative POVM is an extreme point in the convex set of all POVMs if and only if it is a PVM. This results implies that non-commutativity is a necessary ingredient to overcome the limitations of PVMs.

  16. Non-commutativity measure of quantum discord

    PubMed Central

    Guo, Yu

    2016-01-01

    Quantum discord is a manifestation of quantum correlations due to non-commutativity rather than entanglement. Two measures of quantum discord by the amount of non-commutativity via the trace norm and the Hilbert-Schmidt norm respectively are proposed in this paper. These two measures can be calculated easily for any state with arbitrary dimension. It is shown by several examples that these measures can reflect the amount of the original quantum discord. PMID:27122226

  17. Wisconsin Bicycle Driver Training Course. Instructor's Handbook.

    ERIC Educational Resources Information Center

    Thompson, Ronald L.

    Designed for use by trained and certified instructors of a voluntary bicycle driver training course, this handbook provides materials for eight one-hour sessions for beginners or experienced bicyclists. Part 1, Instructor's Guidelines, discusses course objectives, organization, and content; instruction methods; and audiovisual materials. Part 2…

  18. 36 CFR 13.914 - Bicycle use.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Bicycle use. 13.914 Section 13.914 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and Preserve General...

  19. 36 CFR 13.914 - Bicycle use.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Bicycle use. 13.914 Section 13.914 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and Preserve General...

  20. 36 CFR 13.914 - Bicycle use.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Bicycle use. 13.914 Section 13.914 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and Preserve General...

  1. 36 CFR 13.914 - Bicycle use.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Bicycle use. 13.914 Section 13.914 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and Preserve General...

  2. 15 CFR 265.22 - Bicycle traffic.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Bicycle traffic. 265.22 Section 265.22... STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE REGULATIONS GOVERNING TRAFFIC AND CONDUCT REGULATIONS GOVERNING TRAFFIC AND CONDUCT ON THE GROUNDS OF THE NATIONAL INSTITUTE OF STANDARDS &...

  3. 15 CFR 265.22 - Bicycle traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Bicycle traffic. 265.22 Section 265.22... STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE REGULATIONS GOVERNING TRAFFIC AND CONDUCT REGULATIONS GOVERNING TRAFFIC AND CONDUCT ON THE GROUNDS OF THE NATIONAL INSTITUTE OF STANDARDS &...

  4. Solutions to the Triangular Bicycle Flags Problem

    ERIC Educational Resources Information Center

    Hartweg, Kim

    2005-01-01

    Students in a fifth-grade general education class and a second-grade gifted class participated in the Triangular Bicycle Flags problem. The results indicated that providing students with geometric experiences at the correct van Hiele level is necessary for helping students move from one level of understanding to the next.

  5. Bicycle Repair Course of Instruction. Final Report.

    ERIC Educational Resources Information Center

    Humphreys, Harvey

    Developed for an occupational training program in bicycle repair for the multiply-handicapped deaf student, this curriculum guide is organized around three levels of achievement each having a specific terminal objective and corresponding to a predetermined employment entry-level skill. Level I is a general service level; Level II, advanced service…

  6. 36 CFR 1004.30 - Bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... light that is visible from a distance of at least 500 feet to the front and with a red light or... tunnel, or between sunset and sunrise, without exhibiting on the operator or bicycle a white light or reflector that is visible from a distance of at least 500 feet to the front and with a red light...

  7. 36 CFR 1004.30 - Bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... light that is visible from a distance of at least 500 feet to the front and with a red light or... tunnel, or between sunset and sunrise, without exhibiting on the operator or bicycle a white light or reflector that is visible from a distance of at least 500 feet to the front and with a red light...

  8. 36 CFR 13.1126 - Bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Bicycles. 13.1126 Section 13.1126 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Bartlett...

  9. 36 CFR 13.1126 - Bicycles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Bicycles. 13.1126 Section 13.1126 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Bartlett...

  10. 36 CFR 13.1126 - Bicycles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Bicycles. 13.1126 Section 13.1126 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Bartlett...

  11. 36 CFR 13.1126 - Bicycles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Bicycles. 13.1126 Section 13.1126 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Bartlett...

  12. 36 CFR 13.1126 - Bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Bicycles. 13.1126 Section 13.1126 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Bartlett...

  13. 36 CFR 13.1324 - Bicycles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Bicycles. 13.1324 Section 13.1324 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...

  14. 36 CFR 13.1324 - Bicycles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Bicycles. 13.1324 Section 13.1324 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...

  15. 36 CFR 13.1324 - Bicycles.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Bicycles. 13.1324 Section 13.1324 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...

  16. 36 CFR 13.1324 - Bicycles.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Bicycles. 13.1324 Section 13.1324 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...

  17. 36 CFR 13.1324 - Bicycles.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Bicycles. 13.1324 Section 13.1324 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...

  18. 36 CFR 13.914 - Bicycle use.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Bicycle use. 13.914 Section 13.914 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and Preserve General...

  19. A review of commuter exposure to ultrafine particles and its health effects

    NASA Astrophysics Data System (ADS)

    Knibbs, Luke D.; Cole-Hunter, Tom; Morawska, Lidia

    2011-05-01

    Ultrafine particles (UFPs, <100 nm) are produced in large quantities by vehicular combustion and are implicated in causing several adverse human health effects. Recent work has suggested that a large proportion of daily UFP exposure may occur during commuting. However, the determinants, variability and transport mode-dependence of such exposure are not well-understood. The aim of this review was to address these knowledge gaps by distilling the results of 'in-transit' UFP exposure studies performed to-date, including studies of health effects. We identified 47 exposure studies performed across 6 transport modes: automobile, bicycle, bus, ferry, rail and walking. These encompassed approximately 3000 individual trips where UFP concentrations were measured. After weighting mean UFP concentrations by the number of trips in which they were collected, we found overall mean UFP concentrations of 3.4, 4.2, 4.5, 4.7, 4.9 and 5.7 × 10 4 particles cm -3 for the bicycle, bus, automobile, rail, walking and ferry modes, respectively. The mean concentration inside automobiles travelling through tunnels was 3.0 × 10 5 particles cm -3. While the mean concentrations were indicative of general trends, we found that the determinants of exposure (meteorology, traffic parameters, route, fuel type, exhaust treatment technologies, cabin ventilation, filtration, deposition, UFP penetration) exhibited marked variability and mode-dependence, such that it is not necessarily appropriate to rank modes in order of exposure without detailed consideration of these factors. Ten in-transit health effects studies have been conducted and their results indicate that UFP exposure during commuting can elicit acute effects in both healthy and health-compromised individuals. We suggest that future work should focus on further defining the contribution of in-transit UFP exposure to total UFP exposure, exploring its specific health effects and investigating exposures in the developing world.

  20. Holographic charge transport in non commutative gauge theories

    NASA Astrophysics Data System (ADS)

    Roychowdhury, Dibakar

    2015-07-01

    In this paper, based on the holographic techniques, we explore the hydrodynamics of charge diffusion phenomena in non commutative SYM plasma at strong coupling. In our analysis, we compute the R charge diffusion rates both along commutative as well as the non commutative coordinates of the brane. It turns out that unlike the case for the shear viscosity, the DC conductivity along the non commutative direction of the brane differs significantly from that of its cousin corresponding to the commutative direction of the brane. Such a discrepancy however smoothly goes away in the limit of the vanishing non commutativity.

  1. Associations of Physical Activity, Sports Participation and Active Commuting on Mathematic Performance and Inhibitory Control in Adolescents

    PubMed Central

    Huang, Tao; Gejl, Anne Kær; Froberg, Karsten

    2016-01-01

    Objectives To examine objectively measured physical activity level, organized sports participation and active commuting to school in relation to mathematic performance and inhibitory control in adolescents. Methods The design was cross-sectional. A convenient sample of 869 sixth and seventh grade students (12–14 years) was invited to participate in the study. A total of 568 students fulfilled the inclusion criteria and comprised the final sample for this study. Mathematic performance was assessed by a customized test and inhibitory control was assessed by a modified Eriksen flanker task. Physical activity was assessed with GT3X and GT3X+ accelerometers presented in sex-specific quartiles of mean counts per minute and mean minutes per day in moderate-to-vigorous physical activity. Active commuting and sports participation was self-reported. Mixed model regression was applied. Total physical activity level was stratified by bicycling status in order to bypass measurement error subject to the accelerometer. Results Non-cyclists in the 2nd quartile of counts per minute displayed a higher mathematic score, so did cyclists in the 2nd and 3rd quartile of moderate-to-vigorous physical activity relative to the least active quartile. Non-cyclists in the 3rd quartile of counts per minute had an improved reaction time and cyclists in the 2nd quartile of counts per minute and moderate-to-vigorous physical activity displayed an improved accuracy, whereas non-cyclists in the 2nd quartile of counts per minute showed an inferior accuracy relative to the least active quartile. Bicycling to school and organized sports participation were positively associated with mathematic performance. Conclusions Sports participation and bicycling were positively associated with mathematic performance. Results regarding objectively measured physical activity were mixed. Although, no linear nor dose-response relationship was observed there was no indication of a higher activity level impairing the

  2. Probing deformed commutators with macroscopic harmonic oscillators

    PubMed Central

    Bawaj, Mateusz; Biancofiore, Ciro; Bonaldi, Michele; Bonfigli, Federica; Borrielli, Antonio; Di Giuseppe, Giovanni; Marconi, Lorenzo; Marino, Francesco; Natali, Riccardo; Pontin, Antonio; Prodi, Giovanni A.; Serra, Enrico; Vitali, David; Marin, Francesco

    2015-01-01

    A minimal observable length is a common feature of theories that aim to merge quantum physics and gravity. Quantum mechanically, this concept is associated with a nonzero minimal uncertainty in position measurements, which is encoded in deformed commutation relations. In spite of increasing theoretical interest, the subject suffers from the complete lack of dedicated experiments and bounds to the deformation parameters have just been extrapolated from indirect measurements. As recently proposed, low-energy mechanical oscillators could allow to reveal the effect of a modified commutator. Here we analyze the free evolution of high-quality factor micro- and nano-oscillators, spanning a wide range of masses around the Planck mass mP (≈22 μg). The direct check against a model of deformed dynamics substantially lowers the previous limits on the parameters quantifying the commutator deformation. PMID:26088965

  3. Commutative Families of the Elliptic Macdonald Operator

    NASA Astrophysics Data System (ADS)

    Saito, Yosuke

    2014-03-01

    In the paper [J. Math. Phys. 50 (2009), 095215, 42 pages], Feigin, Hashizume, Hoshino, Shiraishi, and Yanagida constructed two families of commuting operators which contain the Macdonald operator (commutative families of the Macdonald operator). They used the Ding-Iohara-Miki algebra and the trigonometric Feigin-Odesskii algebra. In the previous paper [arXiv:1301.4912], the present author constructed the elliptic Ding-Iohara-Miki algebra and the free field realization of the elliptic Macdonald operator. In this paper, we show that by using the elliptic Ding-Iohara-Miki algebra and the elliptic Feigin-Odesskii algebra, we can construct commutative families of the elliptic Macdonald operator. In Appendix, we will show a relation between the elliptic Macdonald operator and its kernel function by the free field realization.

  4. Beating the traffic with commuting alternatives

    SciTech Connect

    1995-05-01

    This pamphlet describes how, by encouraging commuting options, local governments can help reduce air pollution, fuel consumption, and traffic congestion. Minimizing these problems makes the community more appealing to businesses, residents, and visitors and boosts the local economy. Approaches to alternative transportation are as varied as the communities devising and using them. But the critical factor is initiative from local governments, often one of communities largest employers. They can use and promote commuting alternatives among their employees. Local governments can also promote alternative transportation among other employers and the general public. They can provide information on commuting options, improve the infrastructure, and use local authority to require and reward those changes necessary to make alternative transportation a widely accepted part of community life. Best of all, local governments can lead by example and establish a template for other employers to follow.

  5. Fatal falls from bicycles: a case report.

    PubMed

    Venara, A; Mauillon, D; Gaudin, A; Rouge-Maillart, C; Jousset, N

    2013-03-10

    Though rare occurrences, fatal falls from bicycles are generally linked to the absence of a protective helmet and/or a collision with another vehicle. The case presented here is exceptional due to its circumstances and the consequences of the accident: a fall with no obstacle at a low speed that brought about multiple traumas and the death of a cyclist wearing a protective helmet. Comparing this against a review of cyclist accidentology literature, this case is unique. The increased use of autopsy in terms of forensic accidentology is to be encouraged so as not to misunderstand the possibility of such lesion-based consequences following a simple fall from a bicycle. PMID:23312586

  6. Soft-commutated direct current motor

    DOEpatents

    Hsu, J.S.

    1999-07-27

    A method and circuit is disclosed for soft-commutation of a direct current (DC) motor. An attenuation circuit is connected through auxiliary brushes A, A[prime], B and B[prime] to the commutator (16) to drain circuit from successive armature coils (15) before the main brushes (27, 28) disconnects from each of the coils (15). This prevents the spark generation that normally occurs in conventional DC motors. The attenuation circuit may also be connected before energization of the coil (15) for a soft turning on operation. 13 figs.

  7. Soft-commutated direct current motor

    DOEpatents

    Hsu, John S.

    1999-01-01

    A method and circuit is disclosed for soft-commutation of a direct current (DC) motor. An attenuation circuit is connected through auxiliary brushes A, A', B and B' to the commutator (16) to drain circuit from successive armature coils (15) before the main brushes (27, 28) disconnects from each of the coils (15). This prevents the spark generation that normally occurs in conventional DC motors. The attenuation circuit may also be connected before energization of the coil (15) for a soft turning on operation.

  8. Applying riding-posture optimization on bicycle frame design.

    PubMed

    Hsiao, Shih-Wen; Chen, Rong-Qi; Leng, Wan-Lee

    2015-11-01

    Customization design is a trend for developing a bicycle in recent years. Thus, the comfort of riding a bike is an important factor that should be paid much attention to while developing a bicycle. From the viewpoint of ergonomics, the concept of "fitting object to the human body" is designed into the bicycle frame in this study. Firstly, the important feature points of riding posture were automatically detected by the image processing method. In the measurement process, the best riding posture was identified experimentally, thus the positions of feature points and joint angles of human body were obtained. Afterwards, according to the measurement data, three key points: the handlebar, the saddle and the crank center, were identified and applied to the frame design of various bicycle types. Lastly, this study further proposed a frame size table for common bicycle types, which is helpful for the designer to design a bicycle. PMID:26154206

  9. Applying riding-posture optimization on bicycle frame design.

    PubMed

    Hsiao, Shih-Wen; Chen, Rong-Qi; Leng, Wan-Lee

    2015-11-01

    Customization design is a trend for developing a bicycle in recent years. Thus, the comfort of riding a bike is an important factor that should be paid much attention to while developing a bicycle. From the viewpoint of ergonomics, the concept of "fitting object to the human body" is designed into the bicycle frame in this study. Firstly, the important feature points of riding posture were automatically detected by the image processing method. In the measurement process, the best riding posture was identified experimentally, thus the positions of feature points and joint angles of human body were obtained. Afterwards, according to the measurement data, three key points: the handlebar, the saddle and the crank center, were identified and applied to the frame design of various bicycle types. Lastly, this study further proposed a frame size table for common bicycle types, which is helpful for the designer to design a bicycle.

  10. Bicycling and Walking are Associated with Different Cortical Oscillatory Dynamics.

    PubMed

    Storzer, Lena; Butz, Markus; Hirschmann, Jan; Abbasi, Omid; Gratkowski, Maciej; Saupe, Dietmar; Schnitzler, Alfons; Dalal, Sarang S

    2016-01-01

    Although bicycling and walking involve similar complex coordinated movements, surprisingly Parkinson's patients with freezing of gait typically remain able to bicycle despite severe difficulties in walking. This observation suggests functional differences in the motor networks subserving bicycling and walking. However, a direct comparison of brain activity related to bicycling and walking has never been performed, neither in healthy participants nor in patients. Such a comparison could potentially help elucidating the cortical involvement in motor control and the mechanisms through which bicycling ability may be preserved in patients with freezing of gait. The aim of this study was to contrast the cortical oscillatory dynamics involved in bicycling and walking in healthy participants. To this end, EEG and EMG data of 14 healthy participants were analyzed, who cycled on a stationary bicycle at a slow cadence of 40 revolutions per minute (rpm) and walked at 40 strides per minute (spm), respectively. Relative to walking, bicycling was associated with a stronger power decrease in the high beta band (23-35 Hz) during movement initiation and execution, followed by a stronger beta power increase after movement termination. Walking, on the other hand, was characterized by a stronger and persisting alpha power (8-12 Hz) decrease. Both bicycling and walking exhibited movement cycle-dependent power modulation in the 24-40 Hz range that was correlated with EMG activity. This modulation was significantly stronger in walking. The present findings reveal differential cortical oscillatory dynamics in motor control for two types of complex coordinated motor behavior, i.e., bicycling and walking. Bicycling was associated with a stronger sustained cortical activation as indicated by the stronger high beta power decrease during movement execution and less cortical motor control within the movement cycle. We speculate this to be due to the more continuous nature of bicycling demanding

  11. Bicycling and Walking are Associated with Different Cortical Oscillatory Dynamics

    PubMed Central

    Storzer, Lena; Butz, Markus; Hirschmann, Jan; Abbasi, Omid; Gratkowski, Maciej; Saupe, Dietmar; Schnitzler, Alfons; Dalal, Sarang S.

    2016-01-01

    Although bicycling and walking involve similar complex coordinated movements, surprisingly Parkinson’s patients with freezing of gait typically remain able to bicycle despite severe difficulties in walking. This observation suggests functional differences in the motor networks subserving bicycling and walking. However, a direct comparison of brain activity related to bicycling and walking has never been performed, neither in healthy participants nor in patients. Such a comparison could potentially help elucidating the cortical involvement in motor control and the mechanisms through which bicycling ability may be preserved in patients with freezing of gait. The aim of this study was to contrast the cortical oscillatory dynamics involved in bicycling and walking in healthy participants. To this end, EEG and EMG data of 14 healthy participants were analyzed, who cycled on a stationary bicycle at a slow cadence of 40 revolutions per minute (rpm) and walked at 40 strides per minute (spm), respectively. Relative to walking, bicycling was associated with a stronger power decrease in the high beta band (23–35 Hz) during movement initiation and execution, followed by a stronger beta power increase after movement termination. Walking, on the other hand, was characterized by a stronger and persisting alpha power (8–12 Hz) decrease. Both bicycling and walking exhibited movement cycle-dependent power modulation in the 24–40 Hz range that was correlated with EMG activity. This modulation was significantly stronger in walking. The present findings reveal differential cortical oscillatory dynamics in motor control for two types of complex coordinated motor behavior, i.e., bicycling and walking. Bicycling was associated with a stronger sustained cortical activation as indicated by the stronger high beta power decrease during movement execution and less cortical motor control within the movement cycle. We speculate this to be due to the more continuous nature of bicycling

  12. Commutating Permanent-Magnet Motors At Low Speed

    NASA Technical Reports Server (NTRS)

    Dolland, C.

    1985-01-01

    Circuit provides forced commutation during starting. Forced commutation circuit diverts current from inverter SCR's and turns SCR's off during commutation intervals. Silicon controlled rectifier in circuit unnecessary when switch S10 replaced by high-current, high-voltage transistor. At present, high-current, low-voltage device must suffice.

  13. Employees' Perceptions of Cycle Commuting: A Qualitative Study

    ERIC Educational Resources Information Center

    van Bekkum, Jennifer E.; Williams, Joanne M.; Morris, Paul Graham

    2011-01-01

    Purpose: This study aims to provide an in-depth individual level understanding of the psychological factors that affect cycle commuting. Design/methodology/approach: A total of 15 participants (eight cycle commuters and seven potential cycle commuters) from a "cycle-friendly" employer based in a Scottish city took part in the study.…

  14. Potential risk and its influencing factors for separated bicycle paths.

    PubMed

    Xu, Cheng; Yang, Ying; Jin, Sheng; Qu, Zhaowei; Hou, Lei

    2016-02-01

    In this paper, we propose two potential risk indicators to define and evaluate the safety of bicycle path at the microscopic level. Field bicycle data were collected from three survey sites under different traffic conditions. These two risk indicators based on speed dispersion were proposed and calculated during each 5-min interval. The risk influences of various widths of bicycle path and traffic conditions were analyzed by using one-way ANOVA. We further proposed a generalized linear model (GLM) for modeling and analyzing the relationships between bicycle risks and v/c ratio and percentages of electric bicycles, male cyclists, young cyclists, and loaded cyclists. The stepwise regression models were applied for determination of coefficients. The results show that the influences of gender and age of cyclists on potential risks are not significant. The risks increase with the width of bicycle path and percentage of electric bicycles, while only for wider bicycle path (4-lane case in this study), the risks are associated with whether or not cyclists are loaded. The findings could contribute for analysis and evaluation of the safety for bicycle path.

  15. Potential risk and its influencing factors for separated bicycle paths.

    PubMed

    Xu, Cheng; Yang, Ying; Jin, Sheng; Qu, Zhaowei; Hou, Lei

    2016-02-01

    In this paper, we propose two potential risk indicators to define and evaluate the safety of bicycle path at the microscopic level. Field bicycle data were collected from three survey sites under different traffic conditions. These two risk indicators based on speed dispersion were proposed and calculated during each 5-min interval. The risk influences of various widths of bicycle path and traffic conditions were analyzed by using one-way ANOVA. We further proposed a generalized linear model (GLM) for modeling and analyzing the relationships between bicycle risks and v/c ratio and percentages of electric bicycles, male cyclists, young cyclists, and loaded cyclists. The stepwise regression models were applied for determination of coefficients. The results show that the influences of gender and age of cyclists on potential risks are not significant. The risks increase with the width of bicycle path and percentage of electric bicycles, while only for wider bicycle path (4-lane case in this study), the risks are associated with whether or not cyclists are loaded. The findings could contribute for analysis and evaluation of the safety for bicycle path. PMID:26647016

  16. Transport improvement, commuting costs, and residential location

    NASA Technical Reports Server (NTRS)

    Stucker, J. P.

    1973-01-01

    A theoretical framework for evaluating the effects of introducing new transportation on residential travel patterns is presented. Data are based on changes in residential location of urban commuters that alter the mode and length of work trips as well as economic factors.

  17. Quantum Gibbs Samplers: The Commuting Case

    NASA Astrophysics Data System (ADS)

    Kastoryano, Michael J.; Brandão, Fernando G. S. L.

    2016-06-01

    We analyze the problem of preparing quantum Gibbs states of lattice spin Hamiltonians with local and commuting terms on a quantum computer and in nature. Our central result is an equivalence between the behavior of correlations in the Gibbs state and the mixing time of the semigroup which drives the system to thermal equilibrium (the Gibbs sampler). We introduce a framework for analyzing the correlation and mixing properties of quantum Gibbs states and quantum Gibbs samplers, which is rooted in the theory of non-commutative {mathbb{L}_p} spaces. We consider two distinct classes of Gibbs samplers, one of them being the well-studied Davies generator modelling the dynamics of a system due to weak-coupling with a large Markovian environment. We show that their spectral gap is independent of system size if, and only if, a certain strong form of clustering of correlations holds in the Gibbs state. Therefore every Gibbs state of a commuting Hamiltonian that satisfies clustering of correlations in this strong sense can be prepared efficiently on a quantum computer. As concrete applications of our formalism, we show that for every one-dimensional lattice system, or for systems in lattices of any dimension at temperatures above a certain threshold, the Gibbs samplers of commuting Hamiltonians are always gapped, giving an efficient way of preparing the associated Gibbs states on a quantum computer.

  18. Nontraditional, Female, Commuter Students: Coping with College.

    ERIC Educational Resources Information Center

    Rogers, George W., Jr.

    The unique needs of nontraditional, female, commuter students at Northern Kentucky University were examined as a result of active recruitment of nontraditional students in the dwindling market for traditional college students. Women over the age of 25 are entering Northern Kentucky University, bringing unique personal and career problems. Problem…

  19. Propulsion opportunities for future commuter aircraft

    NASA Technical Reports Server (NTRS)

    Strack, W. C.

    1982-01-01

    Circa 1990 propulsion improvement concepts are discussed for 1000 to 5000 SHP conventional turboprop powerplants including engines, gearboxes, and propellers. Cycle selection, power plant configurations and advanced technology elements are defined and evaluated using average stage length DOC for commuter aircraft as the primary merit criterion.

  20. Class 2 design update for the family of commuter airplanes

    NASA Technical Reports Server (NTRS)

    Creighton, Thomas R.; Hendrich, Louis J.

    1987-01-01

    This is the final report of seven on the design of a family of commuter airplanes. This design effort was performed in fulfillment of NASA/USRA grant NGT-8001. Its contents are as follows: (1) the class 1 baseline designs for the commuter airplane family; (2) a study of takeoff weight penalties imposed on the commuter family due to implementing commonality objectives; (3) component structural designs common to the commuter family; (4) details of the acquisition and operating economics of the commuter family, i.e., savings due to production commonality and handling qualities commonality are determined; (5) discussion of the selection of an advanced turboprop propulsion system for the family of commuter airplanes, and (6) a proposed design for an SSSA controller design to achieve similar handling for all airplanes. Final class 2 commuter airplane designs are also presented.

  1. Bicycles in Traffic. A North Carolina Driver Education Handbook.

    ERIC Educational Resources Information Center

    East Carolina Univ., Greenville, NC.

    This unit is designed to provide driver educators with information for teaching automobile drivers about the traffic-mix problem between bicycles and motor vehicles on roadways. The purpose of the unit is to improve the safety of bicyclists on North Carolina highways and help to decrease the number of bicycle deaths and injuries caused by traffic…

  2. An Operator's Guide to Safe and Enjoyable Bicycling.

    ERIC Educational Resources Information Center

    San Jose Dept. of Public Works, CA.

    Addressed to young persons and adults, this booklet delineates the duties and rights applicable to bicyclists as drivers of vehicles. The following topics are discussed: Rules of the road, defensive bicycling techniques, the bicycle as a machine, registration and theft prevention, walking the bike, bike routes, and recreational and group rides.…

  3. Bicycle Freewheeling with Air Drag as a Physics Experiment

    ERIC Educational Resources Information Center

    Janssen, Paul; Janssens, Ewald

    2015-01-01

    To familiarize first-year students with the important ingredients of a physics experiment, we offer them a project close to their daily life: measuring the effect of air resistance on a bicycle. Experiments are done with a bicycle freewheeling on a downhill slope. The data are compared with equations of motions corresponding to different models…

  4. Incidence of Bicycle-Related Injuries in a Defined Population.

    ERIC Educational Resources Information Center

    Thompson, Diane C.; And Others

    1990-01-01

    Analysis of head injuries and total injuries resulting from bicycle crashes among members of a health maintenance organization. Injuries per 100,000 population, per 100 miles ridden, and according to season and day of the week are reported. Individuals between 5 and 14 are at highest risk. The data can be used in community bicycle helmet campaigns…

  5. Bicycle Helmet Laws are Associated with a Lower Fatality Rate from Bicycle-Motor Vehicle Collisions

    PubMed Central

    Meehan, William P.; Lee, Lois K.; Fischer, Christopher M.; Mannix, Rebekah C.

    2013-01-01

    Objective To assess the association between bicycle helmet legislation and bicycle-related deaths sustained by children involved in bicycle-motor vehicle collisions. Study design We conducted a cross sectional study of all bicyclists aged 0-16 years included in the Fatality Analysis Reporting System (FARS) who died between January 1999 and December 2010. We compared fatality rates per age-specific state populations between states with helmet laws and those without helmet laws. We used a clustered Poisson multivariate regression model to adjust for factors previously associated with rates of motor vehicle fatalities: elderly driver licensure laws, legal blood alcohol limit (< 0.08% vs. ≥ 0.08%), and household income. Results A total of 1,612 bicycle-related fatalities were sustained by children <16 years old. There were no statistical differences in median household income, the proportion of states with elderly licensure laws, or the proportion of states with a blood alcohol limit of > 0.08 between states with helmet laws and those without helmet laws. The mean unadjusted rates of fatalities were lower in states with helmet laws (2.0/1,000,000 vs. 2.5/1,000,000; p= 0.03). After adjusting for potential confounding factors, states with mandatory helmet laws continued to be associated with a lower rate of fatalities (adjusted Incidence Rate Ratio 0.84; 95% CI 0.70, 0.98). Conclusions Bicycle helmet safety laws are associated with a lower incidence of fatalities among child bicyclists involved in motor vehicle collisions. PMID:23706604

  6. On Wiener polarity index of bicyclic networks

    NASA Astrophysics Data System (ADS)

    Ma, Jing; Shi, Yongtang; Wang, Zhen; Yue, Jun

    2016-01-01

    Complex networks are ubiquitous in biological, physical and social sciences. Network robustness research aims at finding a measure to quantify network robustness. A number of Wiener type indices have recently been incorporated as distance-based descriptors of complex networks. Wiener type indices are known to depend both on the network’s number of nodes and topology. The Wiener polarity index is also related to the cluster coefficient of networks. In this paper, based on some graph transformations, we determine the sharp upper bound of the Wiener polarity index among all bicyclic networks. These bounds help to understand the underlying quantitative graph measures in depth.

  7. On Wiener polarity index of bicyclic networks

    PubMed Central

    Ma, Jing; Shi, Yongtang; Wang, Zhen; Yue, Jun

    2016-01-01

    Complex networks are ubiquitous in biological, physical and social sciences. Network robustness research aims at finding a measure to quantify network robustness. A number of Wiener type indices have recently been incorporated as distance-based descriptors of complex networks. Wiener type indices are known to depend both on the network’s number of nodes and topology. The Wiener polarity index is also related to the cluster coefficient of networks. In this paper, based on some graph transformations, we determine the sharp upper bound of the Wiener polarity index among all bicyclic networks. These bounds help to understand the underlying quantitative graph measures in depth. PMID:26750820

  8. Two new bicyclic sulfoxides from Welsh onion.

    PubMed

    Nohara, Toshihiro; Fujiwara, Yukio; Ikeda, Tsuyoshi; Murakami, Kotaro; Ono, Masateru; El-Aasr, Mona; Nakano, Daisuke; Kinjo, Junei

    2016-04-01

    Newly identified bicyclic sulfoxides, welsonins A1 (1) and A2 (2), were isolated from acetone extracts of the bulbs of the Welsh onion (Allium fistulosum). In this study, the structures of 1 and 2, which are tetrahydrothiophene-S-oxide derivatives, were characterized by spectroscopic analysis. These compounds appeared to be derived from the coupling of 1-propenyl sulfenic acid and uronic acid. Welsonin A1 (1) showed the potential to suppress tumor-cell proliferation by inhibiting the polarization of alternatively activated M2 macrophages.

  9. Two new bicyclic sulfoxides from Welsh onion.

    PubMed

    Nohara, Toshihiro; Fujiwara, Yukio; Ikeda, Tsuyoshi; Murakami, Kotaro; Ono, Masateru; El-Aasr, Mona; Nakano, Daisuke; Kinjo, Junei

    2016-04-01

    Newly identified bicyclic sulfoxides, welsonins A1 (1) and A2 (2), were isolated from acetone extracts of the bulbs of the Welsh onion (Allium fistulosum). In this study, the structures of 1 and 2, which are tetrahydrothiophene-S-oxide derivatives, were characterized by spectroscopic analysis. These compounds appeared to be derived from the coupling of 1-propenyl sulfenic acid and uronic acid. Welsonin A1 (1) showed the potential to suppress tumor-cell proliferation by inhibiting the polarization of alternatively activated M2 macrophages. PMID:26676612

  10. Persistent groin pain after a bicycle fall.

    PubMed

    Luu, Say-Chong; Jacques, Nicole; Jost, Daniel; Tourtier, Jean-Pierre

    2015-01-01

    Motor scooter handlebar syndrome (MSH) is uncommon. MSH includes groin pain associated with intimal injury to the common femoral artery caused by a direct blow from objects such as a motor scooter handlebar. We describe a case of a 23-year-old man with MSH occurring after a bicycle fall. The diagnosis was performed 5 years after the onset of pain. The patient underwent endovascular surgery and made a rapid recovery. Postoperatively, he was free of symptoms. This case highlights the difficulty of recognising this syndrome. PMID:26678689

  11. Application of bicyclic and cage compounds

    NASA Technical Reports Server (NTRS)

    Clark, R. D.; Archuleta, B. S.

    1976-01-01

    The results of a literature survey of the field of bicyclic and cage compounds were presented, with the objective of identifying those types of compounds with unusual physical and chemical stability, and determining what practical applications have been found for these compounds. Major applications have been as polymers, polymer additives, medicinals, and pesticides. Lesser applications have included fuels, fuel additives, lubricants, lubricant additives, and perfumes. Several areas where further work might be useful were also outlined; these are primarily in the areas of polymers, polymer additives, medicinals, and synthetic lubricants.

  12. On Wiener polarity index of bicyclic networks.

    PubMed

    Ma, Jing; Shi, Yongtang; Wang, Zhen; Yue, Jun

    2016-01-01

    Complex networks are ubiquitous in biological, physical and social sciences. Network robustness research aims at finding a measure to quantify network robustness. A number of Wiener type indices have recently been incorporated as distance-based descriptors of complex networks. Wiener type indices are known to depend both on the network's number of nodes and topology. The Wiener polarity index is also related to the cluster coefficient of networks. In this paper, based on some graph transformations, we determine the sharp upper bound of the Wiener polarity index among all bicyclic networks. These bounds help to understand the underlying quantitative graph measures in depth. PMID:26750820

  13. Quantifying commuter exposures to volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Kayne, Ashleigh

    Motor-vehicles can be a predominant source of air pollution in cities. Traffic-related air pollution is often unavoidable for people who live in populous areas. Commuters may have high exposures to traffic-related air pollution as they are close to vehicle tailpipes. Volatile organic compounds (VOCs) are one class of air pollutants of concern because exposure to VOCs carries risk for adverse health effects. Specific VOCs of interest for this work include benzene, toluene, ethylbenzene, and xylenes (BTEX), which are often found in gasoline and combustion products. Although methods exist to measure time-integrated personal exposures to BTEX, there are few practical methods to measure a commuter's time-resolved BTEX exposure which could identify peak exposures that could be concealed with a time-integrated measurement. This study evaluated the ability of a photoionization detector (PID) to measure commuters' exposure to BTEX using Tenax TA samples as a reference and quantified the difference in BTEX exposure between cyclists and drivers with windows open and closed. To determine the suitability of two measurement methods (PID and Tenax TA) for use in this study, the precision, linearity, and limits of detection (LODs) for both the PID and Tenax TA measurement methods were determined in the laboratory with standard BTEX calibration gases. Volunteers commuted from their homes to their work places by cycling or driving while wearing a personal exposure backpack containing a collocated PID and Tenax TA sampler. Volunteers completed a survey and indicated if the windows in their vehicle were open or closed. Comparing pairs of exposure data from the Tenax TA and PID sampling methods determined the suitability of the PID to measure the BTEX exposures of commuters. The difference between BTEX exposures of cyclists and drivers with windows open and closed in Fort Collins was determined. Both the PID and Tenax TA measurement methods were precise and linear when evaluated in the

  14. The physiological effects of cycling on tandem and single bicycles

    PubMed Central

    Seifert, J; Bacharach, D; Burke, E; Langenfeld, M; Snyder, A

    2003-01-01

    Objective: The purpose of this field study was to compare the physiological responses from cycling on a tandem road bicycle to those from cycling on a single road bicycle. Methods: Nine pairs of experienced, recreational tandem cyclists rode a tandem or their single bicycle for 5 min at each velocity of 19.3, 22.5, 25.8, and 29.0 kph on a flat, paved surface. Heart rate (HR), rating of perceived exertion (RPE), and lactic acid (LA) data were collected after each interval. Results: Riding a tandem resulted in lower HR, RPE, and LA mean values across the four velocities compared to the single bicycle. Mean (SD) HR, RPE, and LA for tandem and single bicycles were 126 (20.7) v 142 (20.1) bpm, 10.1 (1.7) v 11.3 (2.6), and 1.46 (1.0) mM/L v 2.36 (1.7) mM/L, respectively. No position differences were observed between the captain and stoker (front and rear positions) when both were on the tandem. Stokers had significantly lower HR, LA, and RPE values when they rode a tandem compared to a single bicycle. No statistical differences were observed between bicycles for the captains. When on the single bicycle, captains exhibited significantly lower HR, RPE, and LA values than stokers. Conclusion: Cycling on a tandem resulted in lower physiological stress than when cycling at the same velocity on a single bicycle. Cyclists were able to ride from 4.8–8.0 kph faster on a tandem than on a single bicycle at similar physiological stress. Apparently, stokers can add to power output on a tandem without adding significantly to wind resistance. PMID:12547743

  15. Mapping commuter cycling risk in urban areas.

    PubMed

    Yiannakoulias, Nikolaos; Bennet, Scott A; Scott, Darren M

    2012-03-01

    Cycling is becoming an increasingly important transportation option for commuters. Cycling offers exercise opportunities and reduces the burden of motor vehicle travel on society. Mapping the risk of collision between cyclists and motor vehicles in urban areas is important to understanding safe cyclist route opportunities, making informed transportation planning decisions, and exploring patterns of injury epidemiology. To date, many geographic analyses and representations of cyclist risk have not taken the concept of exposure into account. Instead, risk is either expressed as a rate per capita, or as a count of events. Using data associated with the City of Hamilton, Canada, we illustrate a method for mapping commuter cyclist collision risk per distance travelled. This measure can be used to more realistically represent the underlying geography of cycling risk, and provide more geographically and empirically meaningful information to those interested in understanding how cycling safety varies over space. PMID:22269497

  16. Mapping commuter cycling risk in urban areas.

    PubMed

    Yiannakoulias, Nikolaos; Bennet, Scott A; Scott, Darren M

    2012-03-01

    Cycling is becoming an increasingly important transportation option for commuters. Cycling offers exercise opportunities and reduces the burden of motor vehicle travel on society. Mapping the risk of collision between cyclists and motor vehicles in urban areas is important to understanding safe cyclist route opportunities, making informed transportation planning decisions, and exploring patterns of injury epidemiology. To date, many geographic analyses and representations of cyclist risk have not taken the concept of exposure into account. Instead, risk is either expressed as a rate per capita, or as a count of events. Using data associated with the City of Hamilton, Canada, we illustrate a method for mapping commuter cyclist collision risk per distance travelled. This measure can be used to more realistically represent the underlying geography of cycling risk, and provide more geographically and empirically meaningful information to those interested in understanding how cycling safety varies over space.

  17. A study of commuter airplane design optimization

    NASA Technical Reports Server (NTRS)

    Roskam, J.; Wyatt, R. D.; Griswold, D. A.; Hammer, J. L.

    1977-01-01

    Problems of commuter airplane configuration design were studied to affect a minimization of direct operating costs. Factors considered were the minimization of fuselage drag, methods of wing design, and the estimated drag of an airplane submerged in a propellor slipstream; all design criteria were studied under a set of fixed performance, mission, and stability constraints. Configuration design data were assembled for application by a computerized design methodology program similar to the NASA-Ames General Aviation Synthesis Program.

  18. A study of commuter air service

    NASA Technical Reports Server (NTRS)

    Belina, F. W.; Bush, L. R.

    1977-01-01

    A regionally oriented overview of the commuter air service industry is provided. A framework for an eventual assessment of potential technology directions that may be of benefit to the industry is presented. Data are provided on the industry's market characteristics, service patterns, patronage characteristics, aircraft and airport needs, economic characteristics and institutional issues. Using personal interview and literature survey methods, investigation of a considerable cross-section of the industry was made.

  19. Ride quality systems for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Downing, D. R.; Hammond, T. A.; Amin, S. P.

    1983-01-01

    The state-of-the-art in Active Ride Augmentation, specifically in terms of its feasibility for commuter aircraft applications. A literature survey was done, and the principal results are presented here through discussion of different Ride Quality Augmentation System (RQAS) designs and advances in related technologies. Recommended follow-on research areas are discussed, and a preliminary RQAS configuration for detailed design and development is proposed.

  20. p-adic commutation relations

    NASA Astrophysics Data System (ADS)

    Kochubei, Anatoly N.

    1996-10-01

    Representations of the canonical and deformed commutation relations by bounded operators on p-adic Banach spaces are constructed. Functions from the Mahler basis of the space of p-adic continuous functions and their multiplicative analogues are shown to be the p-adic counterparts of the Hermite and q-Hermite functions. The analogue of the Stone - von Neumann uniqueness theorem fails in the p-adic case.

  1. Quantifying commuter exposures to volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Kayne, Ashleigh

    Motor-vehicles can be a predominant source of air pollution in cities. Traffic-related air pollution is often unavoidable for people who live in populous areas. Commuters may have high exposures to traffic-related air pollution as they are close to vehicle tailpipes. Volatile organic compounds (VOCs) are one class of air pollutants of concern because exposure to VOCs carries risk for adverse health effects. Specific VOCs of interest for this work include benzene, toluene, ethylbenzene, and xylenes (BTEX), which are often found in gasoline and combustion products. Although methods exist to measure time-integrated personal exposures to BTEX, there are few practical methods to measure a commuter's time-resolved BTEX exposure which could identify peak exposures that could be concealed with a time-integrated measurement. This study evaluated the ability of a photoionization detector (PID) to measure commuters' exposure to BTEX using Tenax TA samples as a reference and quantified the difference in BTEX exposure between cyclists and drivers with windows open and closed. To determine the suitability of two measurement methods (PID and Tenax TA) for use in this study, the precision, linearity, and limits of detection (LODs) for both the PID and Tenax TA measurement methods were determined in the laboratory with standard BTEX calibration gases. Volunteers commuted from their homes to their work places by cycling or driving while wearing a personal exposure backpack containing a collocated PID and Tenax TA sampler. Volunteers completed a survey and indicated if the windows in their vehicle were open or closed. Comparing pairs of exposure data from the Tenax TA and PID sampling methods determined the suitability of the PID to measure the BTEX exposures of commuters. The difference between BTEX exposures of cyclists and drivers with windows open and closed in Fort Collins was determined. Both the PID and Tenax TA measurement methods were precise and linear when evaluated in the

  2. FET commutated current-FED inverter

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1983-01-01

    A shunt switch comprised of a field-effect transistor (Q.sub.1) is employed to commutate a current-fed inverter (10) using thyristors (SCR1, SCR2) or bijunction transistors (Q.sub.2, Q.sub.3) in a full bridge (1, 2, 3, 4) or half bridge (5, 6) and transformer (T.sub.1) configuration. In the case of thyristors, a tapped inverter (12) is employed to couple the inverter to a dc source to back bias the thyristors during commutation. Alternatively, a commutation power supply (20) may be employed for that purpse. Diodes (D.sub.1, D.sub.2) in series with some voltage dropping element (resistor R.sub.12 or resistors R.sub.1, R.sub.2 or Zener diodes D.sub.4, D.sub.5) are connected in parallel with the thyristors in the half bridge and transformer configuration to assure sharing the back bias voltage. A clamp circuit comprised of a winding (18) negatively coupled to the inductor and a diode (D.sub.3) return stored energy from the inductor to the power supply for efficient operation with buck or boost mode.

  3. Commute alternatives educational outreach. Transportation demand management resource program for the transportation professional. Report for July 1993-December 1994

    SciTech Connect

    Winters, P.L.; Rudge, D.E.

    1995-01-01

    This project is designed to aid in the planning, implementation, evaluation, and improvements of a (TDM) agency of program. Through the use of examples, the TDM professional can review innovative programs and initiatives throughout the United States, and model activities after these exhibits. The equations and benchmarks cited by this publication are other effective tools which offer insights into the relative success of TDM plan components in various environments. This report also introduces many of the traditional and innovative commute alternatives and discusses the benefits, obstacles, and goals of these initiatives. Strategies including carpooling, vanpooling, telecommuting, tax incentives, guaranteed ride home programs, bicycle and pedestrian facilities, transit, telecommuting, alternative work hour programs, and intermodalism are discussed and evaluated in real-world scenarios.

  4. From High-Wheelers to High-Tech: Bicycle Manufacturing Past and Present

    ERIC Educational Resources Information Center

    Kraft, Thomas E.

    2006-01-01

    The 1890s was the heyday for the bicycle in the United States. By 1896, bicycle manufacturing was a major industry with 300 established firms. Interest in bicycling, or "wheeling" as it was known then, grew rapidly into a national craze during the latter part of the 19th century. In 1890, American manufacturers produced nearly 30,000 bicycles, and…

  5. Helmet Wearing Among Users of a Public Bicycle-Sharing Program in the District of Columbia and Comparable Riders on Personal Bicycles

    PubMed Central

    Roffenbender, Jason S.; Anderko, Laura

    2012-01-01

    Bicycle-sharing programs are increasingly popular and have the potential to increase physical activity and decrease air pollution, but anecdotal evidence suggests helmet use is lower among users of bicycle-sharing programs than cyclists on private bicycles. We conducted a cross-sectional study to assess helmet use among users of a bicycle-sharing program in Washington, DC. Helmet use was significantly lower among cyclists on shared bicycles than private bicycles, highlighting a need for targeted helmet promotion activities. PMID:22698021

  6. Battery cars on superconducting magnetically levitated carriers: One commuting solution

    NASA Technical Reports Server (NTRS)

    Briggs, B. Mike; Oman, Henry

    1992-01-01

    Commuting to work in an urban-suburban metropolitan environment is becoming an unpleasant time-wasting process. We applied the technology of communication management to this commuting problem. Communication management is a system-engineering tool that produced today's efficient telephone network. The resulting best commuting option is magnetically levitated carriers of two-passenger, battery-powered, personally-owned local-travel cars. A commuter drives a car to a nearby station, selects a destination, drives on a waiting carrier, and enters an accelerating ramp. A central computer selects an optimum 100 miles-per-hour trunk route, considering existing and forecast traffic; assigns the commuter a travel slot, and subsequently orders switching-station actions. The commuter uses the expensive facilities for only a few minutes during each trip. The cost of travel could be less than 6 cents per mile.

  7. Exposure of commuters to volatile aromatic hydrocarbons from petrol exhaust.

    PubMed

    Löfgren, L; Persson, K; Strömvall, A M; Petersson, G

    1991-10-15

    Twenty-two volatile aromatic hydrocarbons were determined in the air of an automobile during commuting. Sampling was made on Tenax cartridges and laboratory determinations were carried out using thermal desorption combined with temperature-programmed capillary gas chromatography. Selected hydrocarbons representative of petrol exhaust were determined in the automobile and in an electric commuter train during eight parallel commuter trips. In the automobile, the concentrations of benzene were 35-70 micrograms/m3 and those of total aromatic hydrocarbons 200-400 micrograms/m3. The petrol exhaust levels were 5-10 times higher in the automobile than in the compartment of the commuter train.

  8. Bicycle helmet ventilation and comfort angle dependence.

    PubMed

    Brühwiler, Paul A; Ducas, Charline; Huber, Roman; Bishop, Phillip A

    2004-09-01

    Five modern bicycle helmets were studied to elucidate some of the variations in ventilation performance, using both a heated manikin headform and human subjects (n = 7). Wind speed and head angle were varied to test their influence on the measured steady-state heat exchange (cooling power) in the skull section of the headform. The cooling power transmitted by the helmets varied from about 60% to over 90% of that of the nude headform, illustrating the range of present manufacturer designs. Angling the head forward by 30 degrees was found to provide better cooling power to the skull (up to 25%) for three of the helmets and almost equal cooling power in the remaining two cases. Comparisons of skull ventilation at these angles with human subjects strongly supported the headform results.

  9. The bicycle ergometer for muscle power testing.

    PubMed

    Nadeau, M; Brassard, A; Cuerrier, J P

    1983-03-01

    The force-velocity relationship implies that the faster a contracting muscle is permitted to shorten, the weaker it becomes or the slower a contracting muscle is permitted to shorten, the stronger it becomes until it reaches maximal isometric tension. The relationship is hyperbolic for a denervated muscle but is inverse and linear for functionally innervated muscle groups. When the force of contraction is multiplied by the velocity of contraction, a power production curve is obtained. The purposes of the study were to examine the force-velocity relationship on a standard bicycle ergometer, to deduce a power-velocity curve, to compare the results of young men and women and to see if the measures were reproducible. Fifty-eight young men and women volunteered for the study. Testing consisted of pedalling as quickly as possible for five seconds at resistance settings from 2 to 7-kg. In order to evaluate the reproducibility of the scores, retesting was done one hour later. It was shown that the relationship between the resistance settings and the number of revolutions completed by the male and female subjects was inverse and linear. The higher the resistance setting was, the larger was the difference in the scores of the young men and women. When a power curve was derived for each group, a peak power was only identified in the female subjects and this was encountered at a 5-kg resistance setting. The scores obtained at a resistance setting of 5 and 7 kg for female and male subjects respectively showed the best reproducibility. The bicycle ergometer may not be used as an alternative but as a complementary tool to an isokinetic dynamometer.

  10. Non-commutative tools for topological insulators

    NASA Astrophysics Data System (ADS)

    Prodan, Emil

    2010-06-01

    This paper reviews several analytic tools for the field of topological insulators, developed with the aid of non-commutative calculus and geometry. The set of tools includes bulk topological invariants defined directly in the thermodynamic limit and in the presence of disorder, whose robustness is shown to have nontrivial physical consequences for the bulk states. The set of tools also includes a general relation between the current of an observable and its edge index, a relation that can be used to investigate the robustness of the edge states against disorder. The paper focuses on the motivations behind creating such tools and on how to use them.

  11. The effect of commuting microenvironment on commuter exposures to vehicular emission in Hong Kong

    NASA Astrophysics Data System (ADS)

    Chan, L. Y.; Chan, C. Y.; Qin, Y.

    Vehicular exhaust emission has gradually become the major air pollution source in modern cities and traffic related exposure is found to contribute significantly to total human exposure level. A comprehensive survey was conducted from November 1995 to July 1996 in Hong Kong to assess the effect of traffic-induced air pollution inside different commuting microenvironments on commuter exposure. Microenvironmental monitoring is performed for six major public commuting modes (bus, light bus, MTR, railway, tram, ferry), plus private car and roadside pavement. Traffic-related pollutants, CO, NO x, THC and O 3 were selected as the target pollutants. The results indicate that commuter exposure is highly influenced by the choice of commuting microenvironment. In general, the exposure level in decreasing order of measured pollutant level for respective commuting microenvironments are: private car, the group consisting light bus, bus, tram and pavement, MTR and train, and finally ferry. In private car, the CO level is several times higher than that in the other microenvironments with a trip averaged of 10.1 ppm and a maximum of 24.9 ppm. Factors such as the body position of the vehicle, intake point of the ventilation system, fuel used, ventilation, transport mode, road and driving conditions were used in the analysis. Inter-microenvironment, intra-microenvironment and temporal variation of CO concentrations were used as the major indicator. The low body position and low intake point of the ventilation system of the private car are believed to be the cause of higher intake of exhaust of other vehicles and thus result in high pollution level in this microenvironment. Compared with other metropolis around the world and the Hong Kong Air Quality Objectives (HKAQO), exposure levels of commuter to traffic-related air pollution in Hong Kong are relatively low for most pollutants measured. Only several cases of exceedence of HKAQO by NO 2 were recorded. The strong prevailing wind

  12. 4. FACING EAST ACROSS BRIDGE AT HALF DOME WITH BICYCLE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. FACING EAST ACROSS BRIDGE AT HALF DOME WITH BICYCLE PATH MARKERS IN FOREGROUND AND ELECTRICAL TRANSFORMER FOR CAMPGROUND TO RIGHT. - Ahwahnee Bridge, Spanning Merced River on service road, Yosemite Village, Mariposa County, CA

  13. Fluid Mechanics of a High Performance Racing Bicycle Wheel

    NASA Astrophysics Data System (ADS)

    Mercat, Jean-Pierre; Cretoux, Brieuc; Huat, Francois-Xavier; Nordey, Benoit; Renaud, Maxime; Noca, Flavio

    2013-11-01

    In 2012, MAVIC released the most aerodynamic bicycle wheel on the market, the CXR 80. The french company MAVIC has been a world leader for many decades in the manufacturing of bicycle wheels for competitive events such as the Olympic Games and the Tour de France. Since 2010, MAVIC has been in a research partnership with the University of Applied Sciences in Geneva, Switzerland, for the aerodynamic development of bicycle wheels. While most of the development up to date has been performed in a classical wind tunnel, recent work has been conducted in an unusual setting, a hydrodynamic towing tank, in order to achieve low levels of turbulence and facilitate quantitative flow visualization (PIV). After a short introduction on the aerodynamics of bicycle wheels, preliminary fluid mechanics results based on this novel setup will be presented.

  14. On the Skill of Balancing While Riding a Bicycle.

    PubMed

    Cain, Stephen M; Ashton-Miller, James A; Perkins, Noel C

    2016-01-01

    Humans have ridden bicycles for over 200 years, yet there are no continuous measures of how skill differs between novice and expert. To address this knowledge gap, we measured the dynamics of human bicycle riding in 14 subjects, half of whom were skilled and half were novice. Each subject rode an instrumented bicycle on training rollers at speeds ranging from 1 to 7 m/s. Steer angle and rate, steer torque, bicycle speed, and bicycle roll angle and rate were measured and steering power calculated. A force platform beneath the roller assembly measured the net force and moment that the bicycle, rider and rollers exerted on the floor, enabling calculations of the lateral positions of the system centers of mass and pressure. Balance performance was quantified by cross-correlating the lateral positions of the centers of mass and pressure. The results show that all riders exhibited similar balance performance at the slowest speed. However at higher speeds, the skilled riders achieved superior balance performance by employing more rider lean control (quantified by cross-correlating rider lean angle and bicycle roll angle) and less steer control (quantified by cross-correlating steer rate and bicycle roll rate) than did novice riders. Skilled riders also used smaller steering control input with less variation (measured by average positive steering power and standard deviations of steer angle and rate) and less rider lean angle variation (measured by the standard deviation of the rider lean angle) independent of speed. We conclude that the reduction in balance control input by skilled riders is not due to reduced balance demands but rather to more effective use of lean control to guide the center of mass via center of pressure movements.

  15. Does Promoting Bicycle-Helmet Wearing Reduce Childhood Head Injuries?

    ERIC Educational Resources Information Center

    Farley, Celine; Vaez, Marjan; Laflamme, Lucie

    2004-01-01

    The objectives of the study are to assess the impact of a community-based bicycle-helmet program aimed at children aged 5-12 years (about 140,000). A quasi-experimental design, including a control group, was used. Sex- and age-group-based changes in the risk of bicycle-related head injury leading to hospitalisation were measured, using rate…

  16. On the Skill of Balancing While Riding a Bicycle.

    PubMed

    Cain, Stephen M; Ashton-Miller, James A; Perkins, Noel C

    2016-01-01

    Humans have ridden bicycles for over 200 years, yet there are no continuous measures of how skill differs between novice and expert. To address this knowledge gap, we measured the dynamics of human bicycle riding in 14 subjects, half of whom were skilled and half were novice. Each subject rode an instrumented bicycle on training rollers at speeds ranging from 1 to 7 m/s. Steer angle and rate, steer torque, bicycle speed, and bicycle roll angle and rate were measured and steering power calculated. A force platform beneath the roller assembly measured the net force and moment that the bicycle, rider and rollers exerted on the floor, enabling calculations of the lateral positions of the system centers of mass and pressure. Balance performance was quantified by cross-correlating the lateral positions of the centers of mass and pressure. The results show that all riders exhibited similar balance performance at the slowest speed. However at higher speeds, the skilled riders achieved superior balance performance by employing more rider lean control (quantified by cross-correlating rider lean angle and bicycle roll angle) and less steer control (quantified by cross-correlating steer rate and bicycle roll rate) than did novice riders. Skilled riders also used smaller steering control input with less variation (measured by average positive steering power and standard deviations of steer angle and rate) and less rider lean angle variation (measured by the standard deviation of the rider lean angle) independent of speed. We conclude that the reduction in balance control input by skilled riders is not due to reduced balance demands but rather to more effective use of lean control to guide the center of mass via center of pressure movements. PMID:26910774

  17. On the Skill of Balancing While Riding a Bicycle

    PubMed Central

    Cain, Stephen M.; Ashton-Miller, James A.; Perkins, Noel C.

    2016-01-01

    Humans have ridden bicycles for over 200 years, yet there are no continuous measures of how skill differs between novice and expert. To address this knowledge gap, we measured the dynamics of human bicycle riding in 14 subjects, half of whom were skilled and half were novice. Each subject rode an instrumented bicycle on training rollers at speeds ranging from 1 to 7 m/s. Steer angle and rate, steer torque, bicycle speed, and bicycle roll angle and rate were measured and steering power calculated. A force platform beneath the roller assembly measured the net force and moment that the bicycle, rider and rollers exerted on the floor, enabling calculations of the lateral positions of the system centers of mass and pressure. Balance performance was quantified by cross-correlating the lateral positions of the centers of mass and pressure. The results show that all riders exhibited similar balance performance at the slowest speed. However at higher speeds, the skilled riders achieved superior balance performance by employing more rider lean control (quantified by cross-correlating rider lean angle and bicycle roll angle) and less steer control (quantified by cross-correlating steer rate and bicycle roll rate) than did novice riders. Skilled riders also used smaller steering control input with less variation (measured by average positive steering power and standard deviations of steer angle and rate) and less rider lean angle variation (measured by the standard deviation of the rider lean angle) independent of speed. We conclude that the reduction in balance control input by skilled riders is not due to reduced balance demands but rather to more effective use of lean control to guide the center of mass via center of pressure movements. PMID:26910774

  18. Bicycling safety and distracted behavior in The Hague, the Netherlands.

    PubMed

    Terzano, Kathryn

    2013-08-01

    As planners and public health officials in many cities around the world seek to increase bicycle ridership, bicyclists who are performing a secondary task (such as listening to a portable music device) may pose a risk to public safety. This study examines bicycling safety and potentially distracted behavior in The Hague, the Netherlands, a place where bicycling is a common, everyday travel mode among all walks of life and where bicycling infrastructure is well developed. Based on 1360 observations of bicycling behavior, this study shows that bicyclists who were using a cell phone, listening to a portable music device, or talking with other bicyclists exhibited more unsafe behaviors than those bicyclists who were not performing a secondary task. Furthermore, bicyclists who were performing a secondary task also more frequently created situations where other people had to evade them to avoid an accident. As with distracted car driving, the performance of a secondary task while bicycling may be unsafe for the person engaging in the behavior as well as for other people around them.

  19. Bicycle helmet use and non-use - recently published research.

    PubMed

    Uibel, Stefanie; Müller, Daniel; Klingelhoefer, Doris; Groneberg, David A

    2012-05-25

    Bicycle traumata are very common and especially neurologic complications lead to disability and death in all stages of the life. This review assembles the most recent findings concerning research in the field of bicycle traumata combined with the factor of bicycle helmet use. The area of bicycle trauma research is by nature multidisciplinary and relevant not only for physicians but also for experts with educational, engineering, judicial, rehabilitative or public health functions. Due to this plurality of global publications and special subjects, short time reviews help to detect recent research directions and provide also information from neighbour disciplines for researchers. It can be stated that to date, that although a huge amount of research has been conducted in this area more studies are needed to evaluate and improve special conditions and needs in different regions, ages, nationalities and to create successful prevention programs of severe head and face injuries while cycling.Focus was explicit the bicycle helmet use, wherefore sledding, ski and snowboard studies were excluded and only one study concerning electric bicycles remained due to similar motion structures within this review. The considered studies were all published between January 2010 and August 2011 and were identified via the online databases Medline PubMed and ISI Web of Science.

  20. The metabolic cost of operating a bicycle generator light.

    PubMed

    Langenfeld, Mark E; Pujol, Thomas J; Moran, Meghan K; Barnes, Jeremy T; Scheeter, Randy L; Jones, Eric J

    2002-12-15

    The purpose of the study was to determine the metabolic cost of operating a bicycle generator (dynamo) light. Nineteen subjects (12 males, 7 females) volunteered to participate in the study. All tests were conducted using a multigeared road bicycle mounted on a Velodyne computer-controlled, electromagnetically-braked bicycle training simulator. A tyre sidewall-driven 6V 3W bicycle generator was attached to the bicycle frame. Tyre pressure was maintained at 6.12 atm. Gears were prescribed to produce simulated riding speeds of approximately 13 and 21 km h(-1) at 62 rpm. Subjects rode four, 5-min stages during the test session to evaluate riding under conditions of generator OFF or ON at each speed. Oxygen consumption, heart rate, and rating of perceived exertion (RPE) were recorded at the end of each minute. Paired samples t tests revealed significant differences between generator OFF and ON conditions for both the metabolic cost of cycling and heart rate at each of the speeds tested. There were no significant differences found between conditions for RPE. Bicycling with the generator ON increased oxygen consumption by 8.4% at 13 km h(-1) and 9.6% at 21 km h(-1).

  1. The metabolic cost of operating a bicycle generator light.

    PubMed

    Langenfeld, Mark E; Pujol, Thomas J; Moran, Meghan K; Barnes, Jeremy T; Scheeter, Randy L; Jones, Eric J

    2002-12-15

    The purpose of the study was to determine the metabolic cost of operating a bicycle generator (dynamo) light. Nineteen subjects (12 males, 7 females) volunteered to participate in the study. All tests were conducted using a multigeared road bicycle mounted on a Velodyne computer-controlled, electromagnetically-braked bicycle training simulator. A tyre sidewall-driven 6V 3W bicycle generator was attached to the bicycle frame. Tyre pressure was maintained at 6.12 atm. Gears were prescribed to produce simulated riding speeds of approximately 13 and 21 km h(-1) at 62 rpm. Subjects rode four, 5-min stages during the test session to evaluate riding under conditions of generator OFF or ON at each speed. Oxygen consumption, heart rate, and rating of perceived exertion (RPE) were recorded at the end of each minute. Paired samples t tests revealed significant differences between generator OFF and ON conditions for both the metabolic cost of cycling and heart rate at each of the speeds tested. There were no significant differences found between conditions for RPE. Bicycling with the generator ON increased oxygen consumption by 8.4% at 13 km h(-1) and 9.6% at 21 km h(-1). PMID:12569046

  2. [Bicycle spoke-related injuries in children: emphasise prevention].

    PubMed

    Kramer, William L M; Haaring, Gert-Jan

    2011-01-01

    Three children, a 6-year-old boy and two girls aged 5 and 4 years, were seen at an emergency department due to distal lower-leg injuries sustained from the spokes of bicycle wheels. All three patients had been passengers on rear carrying seats of moving bicycles. Only the third bicyclist had used a special child safety seat. The second girl had drawn her foot up from underneath a strap and suffered a tibial fracture later treated with an osteosynthetic plate. The other two patients recovered after conservative casting treatment. Bicycle spoke-related injuries are sustained when the foot or lower limb makes contact with the spokes of a bicycle wheel and usually by children who are bicycle passengers. In the Netherlands, approximately 4600 children are seen at emergency departments with such injuries each year. Bicycle spoke-related accidents can cause severe damage that can result in lengthy recovery periods. Not only physical complications but also psychological ones can occur. The latter are often overlooked but do deserve proper treatment. The physician treating a spoke-related injury is in a good position to advice parents as to preventive measures, particularly on the use of special child safety seats.

  3. Measuring sideslip and camber characteristics of bicycle tyres

    NASA Astrophysics Data System (ADS)

    Dressel, Andrew; Rahman, Adeeb

    2012-08-01

    Sideslip and camber tyre properties, the forces and moments a tyre generates as it rolls forward under different circumstances, have been found to be important to motorcycle dynamics. A similar situation may be expected to exist for bicycles, but limited bicycle tyre data and a lack of the tools necessary to measure it may contribute to its absence in bicycle dynamics analyses. Measuring these properties requires holding the tyre at a fixed orientation with respect to the pavement and its direction of travel, and then measuring the lateral force and torque about the steer axis generated as the tyre rolls forward. Devices exist for measuring these characteristics of automobile tyres. One device is known to exist specifically for motorcycle tyres, and it has been used at least once on bicycle tyres, but the minimum load it can apply is nearly double the actual load carried by most bicycle tyres. This paper presents a low-cost device that measures bicycle tyre cornering stiffness and camber stiffness.

  4. Test verification and design of the bicycle frame parameters

    NASA Astrophysics Data System (ADS)

    Zhang, Long; Xiang, Zhongxia; Luo, Huan; Tian, Guan

    2015-07-01

    Research on design of bicycles is concentrated on mechanism and auto appearance design, however few on matches between the bike and the rider. Since unreasonable human-bike relationship leads to both riders' worn-out joints and muscle injuries, the design of bicycles should focus on the matching. In order to find the best position of human-bike system, simulation experiments on riding comfort under different riding postures are done with the lifemode software employed to facilitate the cycling process as well as to obtain the best position and the size function of it. With BP neural network and GA, analyzing simulation data, conducting regression analysis of parameters on different heights and bike frames, the equation of best position of human-bike system is gained at last. In addition, after selecting testers, customized bikes based on testers' height dimensions are produced according to the size function. By analyzing and comparing the experimental data that are collected from testers when riding common bicycles and customized bicycles, it is concluded that customized bicycles are four times even six times as comfortable as common ones. The equation of best position of human-bike system is applied to improve bikes' function, and the new direction on future design of bicycle frame parameters is presented.

  5. Shock Waves and Commutation Speed of Memristors

    NASA Astrophysics Data System (ADS)

    Tang, Shao; Tesler, Federico; Marlasca, Fernando Gomez; Levy, Pablo; Dobrosavljević, V.; Rozenberg, Marcelo

    2016-01-01

    Progress of silicon-based technology is nearing its physical limit, as the minimum feature size of components is reaching a mere 10 nm. The resistive switching behavior of transition metal oxides and the associated memristor device is emerging as a competitive technology for next-generation electronics. Significant progress has already been made in the past decade, and devices are beginning to hit the market; however, this progress has mainly been the result of empirical trial and error. Hence, gaining theoretical insight is of the essence. In the present work, we report the striking result of a connection between the resistive switching and shock-wave formation, a classic topic of nonlinear dynamics. We argue that the profile of oxygen vacancies that migrate during the commutation forms a shock wave that propagates through a highly resistive region of the device. We validate the scenario by means of model simulations and experiments in a manganese-oxide-based memristor device, and we extend our theory to the case of binary oxides. The shock-wave scenario brings unprecedented physical insight and enables us to rationalize the process of oxygen-vacancy-driven resistive change with direct implications for a key technological aspect—the commutation speed.

  6. Reducing employee travelling time through smart commuting

    NASA Astrophysics Data System (ADS)

    Rahman, A. N. N. A.; Yusoff, Z. M.; Aziz, I. S.; Omar, D.

    2014-02-01

    Extremely congested roads will definitely delay the arrival time of each trip.This certainly impacted the journey of employees. Tardiness at the workplace has become a perturbing issue for companies where traffic jams are the most common worker excuses. A depressing consequence on daily life and productivity of the employee occurs. The issues of commuting distance between workplace and resident area become the core point of this research. This research will emphasize the use of Geographical Information System (GIS) technique to explore the distance parameter to the employment area and will focus on the accessibility pattern of low-cost housing. The research methodology consists of interview sessions and a questionnaire to residents of low-cost housing areas in Melaka Tengah District in Malaysia. The combination of these processes will show the criteria from the selected parameter for each respondent from their resident area to the employment area. This will further help in the recommendation of several options for a better commute or improvement to the existing routes and public transportations system. Thus enhancing quality of life for employees and helping to reduce stress, decrease lateness, absenteeism and improving productivity in workplace.

  7. Non-commutative relativistic equation with a Coulomb potential

    SciTech Connect

    Zaim, Slimane; Khodja, Lamine; Delenda, Yazid

    2012-06-27

    We improve the previous study of the Klein-Gordon equation in a non-commutative space-time as applied to the Hydrogen atom to extract the energy levels, by considering the secondorder corrections in the non-commutativity parameter. Phenomenologically we show that noncommutativity plays the role of spin.

  8. Impact of commuter-rail services in Toronto region

    SciTech Connect

    Wells, S.S.; Hutchinson, B.G.

    1996-07-01

    Ridership of the commuter-rail system that was implemented in the Greater Toronto Area (GTA) in 1967 increased at an annual, average compound rate of 11.4% until 1989. Demand has leveled substantially during 1990--94 and has averaged only 2.1% per year, which probably reflects the suburbanization of employment. Urban economic theory is used to explain the way in which central-business-district (CBD) employees respond differently to suburban commuter-rail services and rapid transit services, mainly serving the inner intermediate suburbs. Travel data collected in 1986 and 1991 confirmed the effects suggested by the theory. Commuter-rail passengers are drawn from the larger suburban households, living principally in single-family houses, and commuter-rail passengers are more sensitive to access and egress distances than subway passengers. Policies that improve the quality of access and egress components of commuting trips from the suburbs stimulate passenger demand. Also, land-use policies that promote high-density, residential development at suburban commuter-rail stations are unlikely to contribute significantly to commuter-rail demand, and the lakeshore commuter-rail line that has been in service since 1967 has not had a significant impact on residential sorting and on the generation of additional demands.

  9. Understanding What Influences Successful Black Commuter Students' Engagement in College

    ERIC Educational Resources Information Center

    Yearwood, Trina Lynn; Jones, Elizabeth A.

    2012-01-01

    Black and commuter students are disadvantaged when it comes to higher education. Although black students are enrolling in college more than they did in previous years, fewer are earning degrees compared with their counterparts. Research asserts that students who live on campus are more engaged compared with students who commute. This is troubling…

  10. Unraveling the Image of Commutation Spark Generated in Universal Motors

    NASA Astrophysics Data System (ADS)

    Hanazawa, Tamio; Almazroui, Ali; Egashira, Torao

    A universal motor, which is mainly used in vacuum cleaners, generates commutation sparks at the moment when the brush and the commutator segment are separated from each other during rotation. This study investigates the mechanism of commutation spark generation by analyzing high-speed camera images and its electrical aspect. We invented a new external trigger method that used laser light as the trigger signal for the shuttering a high-speed camera. This method enabled us to photograph sparks on any desired commutator segments during high-speed rotation, and that made the analysis after photographing easier. This paper shows that commutation sparks in universal motors are generated on every other commutator segment and at the peak of pulses in the voltage between the brush and commutator segment. Other aspects are also clarified, such as the generation of the singular and plural number of sparks on one commutator segment at a time, the time from the moment of spark generation to extinction, and spark generation during a single rotation.

  11. Active Commuting Patterns at a Large, Midwestern College Campus

    ERIC Educational Resources Information Center

    Bopp, Melissa; Kaczynski, Andrew; Wittman, Pamela

    2011-01-01

    Objective: To understand patterns and influences on active commuting (AC) behavior. Participants: Students and faculty/staff at a university campus. Methods: In April-May 2008, respondents answered an online survey about mode of travel to campus and influences on commuting decisions. Hierarchical regression analyses predicted variance in walking…

  12. Parabosonic string and space-time non-commutativity

    SciTech Connect

    Seridi, M. A.; Belaloui, N.

    2012-06-27

    We investigate the para-quantum extension of the bosonic strings in a non-commutative space-time. We calculate the trilinear relations between the mass-center variables and the modes and we derive the Virasoro algebra where a new anomaly term due to the non-commutativity is obtained.

  13. Soft commutated direct current motor [summary of proposed paper

    SciTech Connect

    Hsu, John S.

    1998-10-22

    A novel soft commutated direct current (DC) motor is introduced. The current of the commutated coil is intentionally drained before the brush disconnects the coil. This prevents the spark generation that normally occurs in conventional DC motors. A similar principle can be applied for DC generators.

  14. Effects of urban growth controls on intercity commuting.

    PubMed

    Ogura, Laudo M

    2010-01-01

    This paper presents an empirical study of the effects of urban growth controls on the intercity commuting of workers. Growth controls (land use regulations that attempt to restrict population growth and urban sprawl) have increased housing prices and diverted population growth to uncontrolled cities. It has been suggested that resulting changes in local labour supply might stimulate intercity commuting from uncontrolled to controlled cities. To test this hypothesis, a gravity model of commuting flows between places in California is estimated using alternative econometric methods (OLS, Heckman selection and count-data). The possibility of spatial dependence in commuting flows is also taken into consideration. Results suggest larger commuting flows to destination places that restrict residential growth. PMID:20722227

  15. Euler polynomials and identities for non-commutative operators

    NASA Astrophysics Data System (ADS)

    De Angelis, Valerio; Vignat, Christophe

    2015-12-01

    Three kinds of identities involving non-commutating operators and Euler and Bernoulli polynomials are studied. The first identity, as given by Bender and Bettencourt [Phys. Rev. D 54(12), 7710-7723 (1996)], expresses the nested commutator of the Hamiltonian and momentum operators as the commutator of the momentum and the shifted Euler polynomial of the Hamiltonian. The second one, by Pain [J. Phys. A: Math. Theor. 46, 035304 (2013)], links the commutators and anti-commutators of the monomials of the position and momentum operators. The third appears in a work by Figuieira de Morisson and Fring [J. Phys. A: Math. Gen. 39, 9269 (2006)] in the context of non-Hermitian Hamiltonian systems. In each case, we provide several proofs and extensions of these identities that highlight the role of Euler and Bernoulli polynomials.

  16. Effects of urban growth controls on intercity commuting.

    PubMed

    Ogura, Laudo M

    2010-01-01

    This paper presents an empirical study of the effects of urban growth controls on the intercity commuting of workers. Growth controls (land use regulations that attempt to restrict population growth and urban sprawl) have increased housing prices and diverted population growth to uncontrolled cities. It has been suggested that resulting changes in local labour supply might stimulate intercity commuting from uncontrolled to controlled cities. To test this hypothesis, a gravity model of commuting flows between places in California is estimated using alternative econometric methods (OLS, Heckman selection and count-data). The possibility of spatial dependence in commuting flows is also taken into consideration. Results suggest larger commuting flows to destination places that restrict residential growth.

  17. Reviving a ghost in the history of technology: the social construction of the recumbent bicycle.

    PubMed

    Ahmed, Hassaan; Qureshi, Omer Masood; Khan, Abid Ali

    2015-02-01

    Recumbent bicycles have never truly been associated with international cycling. Conventional safety (upright) bicycles have long been at the center of the cycling world, for both sport and transportation. This is despite the fact that recumbent bicycles are faster, more comfortable, and more efficient than the upright bicycles. The aim of this article is to explain the historical and social perspectives that led to the rejection of the recumbent bicycle by utilizing the theory of Social Construction of Technology (SCOT) and Bijker's two power theory, providing a contrast with the adoption of the safety bicycle.

  18. Built environment influences on healthy transportation choices: bicycling versus driving.

    PubMed

    Winters, Meghan; Brauer, Michael; Setton, Eleanor M; Teschke, Kay

    2010-12-01

    A growing body of evidence links the built environment to physical activity levels, health outcomes, and transportation behaviors. However, little of this research has focused on cycling, a sustainable transportation option with great potential for growth in North America. This study examines associations between decisions to bicycle (versus drive) and the built environment, with explicit consideration of three different spatial zones that may be relevant in travel behavior: trip origins, trip destinations, and along the route between. We analyzed 3,280 utilitarian bicycle and car trips in Metro Vancouver, Canada made by 1,902 adults, including both current and potential cyclists. Objective measures were developed for built environment characteristics related to the physical environment, land use patterns, the road network, and bicycle-specific facilities. Multilevel logistic regression was used to model the likelihood that a trip was made by bicycle, adjusting for trip distance and personal demographics. Separate models were constructed for each spatial zone, and a global model examined the relative influence of the three zones. In total, 31% (1,023 out of 3,280) of trips were made by bicycle. Increased odds of bicycling were associated with less hilliness; higher intersection density; less highways and arterials; presence of bicycle signage, traffic calming, and cyclist-activated traffic lights; more neighborhood commercial, educational, and industrial land uses; greater land use mix; and higher population density. Different factors were important within each spatial zone. Overall, the characteristics of routes were more influential than origin or destination characteristics. These findings indicate that the built environment has a significant influence on healthy travel decisions, and spatial context is important. Future research should explicitly consider relevant spatial zones when investigating the relationship between physical activity and urban form.

  19. A non-commuting stabilizer formalism

    SciTech Connect

    Ni, Xiaotong; Van den Nest, Maarten; Buerschaper, Oliver

    2015-05-15

    We propose a non-commutative extension of the Pauli stabilizer formalism. The aim is to describe a class of many-body quantum states which is richer than the standard Pauli stabilizer states. In our framework, stabilizer operators are tensor products of single-qubit operators drawn from the group 〈αI, X, S〉, where α = e{sup iπ/4} and S = diag(1, i). We provide techniques to efficiently compute various properties related to bipartite entanglement, expectation values of local observables, preparation by means of quantum circuits, parent Hamiltonians, etc. We also highlight significant differences compared to the Pauli stabilizer formalism. In particular, we give examples of states in our formalism which cannot arise in the Pauli stabilizer formalism, such as topological models that support non-Abelian anyons.

  20. Accelerating commutation circuits in quantum computer networks

    NASA Astrophysics Data System (ADS)

    Jiang, Min; Huang, Xu; Chen, Xiaoping; Zhang, Zeng-ke

    2012-12-01

    In a high speed and packet-switched quantum computer network, a packet routing delay often leads to traffic jams, becoming a severe bottleneck for speeding up the transmission rate. Based on the delayed commutation circuit proposed in Phys. Rev. Lett. 97, 110502 (2006), we present an improved scheme for accelerating network transmission. For two more realistic scenarios, we utilize the characteristic of a quantum state to simultaneously implement a data switch and transmission that makes it possible to reduce the packet delay and route a qubit packet even before its address is determined. This circuit is further extended to the quantum network for the transmission of the unknown quantum information. The analysis demonstrates that quantum communication technology can considerably reduce the processing delay time and build faster and more efficient packet-switched networks.

  1. Electronically commutated dc motors for electric vehicles

    NASA Technical Reports Server (NTRS)

    Maslowski, E. A.

    1981-01-01

    A motor development program to explore the feasibility of electronically commutated dc motors (also known as brushless) for electric cars is described. Two different design concepts and a number of design variations based on these concepts are discussed. One design concept is based on a permanent magnet, medium speed, machine rated at 7000 to 9000 rpm, and powered via a transistor inverter power conditioner. The other concept is based on a permanent magnet, high speed, machine rated at 22,000 to 26,000 rpm, and powered via a thyristor inverter power conditioner. Test results are presented for a medium speed motor and a high speed motor each of which have been fabricated using samarium cobalt permanent magnet material.

  2. Electronically commutated dc motors for electric vehicles

    NASA Astrophysics Data System (ADS)

    Maslowski, E. A.

    A motor development program to explore the feasibility of electronically commutated dc motors (also known as brushless) for electric cars is described. Two different design concepts and a number of design variations based on these concepts are discussed. One design concept is based on a permanent magnet, medium speed, machine rated at 7000 to 9000 rpm, and powered via a transistor inverter power conditioner. The other concept is based on a permanent magnet, high speed, machine rated at 22,000 to 26,000 rpm, and powered via a thyristor inverter power conditioner. Test results are presented for a medium speed motor and a high speed motor each of which have been fabricated using samarium cobalt permanent magnet material.

  3. Electronically commutated motors for vehicle applications

    NASA Astrophysics Data System (ADS)

    Echolds, E. F.

    1980-02-01

    Two permanent magnet electronically commutated motors for electric vehicle traction are discussed. One, based on existing technology, produces 23 kW (peak) at 26,000 rpm, and 11 kW continuous at 18,000 rpm. The motor has a conventional design: a four-pole permanent magnet rotor and a three-phase stator similar to those used on ordinary induction motors. The other, advanced technology motor, is rated at 27 kW (peak) at 14,000 rpm, and 11 kW continuous at 10,500 rpm. The machine employs a permanent magnet rotor and a novel ironless stator design in an axial air gap, homopolar configuration. Comparison of the new motors with conventional brush type machines indicates potential for substantial cost savings.

  4. Commuting behavior of western U.S. residents

    SciTech Connect

    Caviglia, J. |

    1996-06-01

    Estimation and interpretation of commutes to work has been studied extensively with respect to gender, race, and income. While the literature is extensive in these areas, there has been little research on regional differences between US states and territories. Since data which reports the commute to work is in average minutes, the distance traveled is estimated using estimates of the distance between home and work county centroids. The models differ in estimation of in-county commutes. The first assumes that the commute is equal to the radius of the county and the second estimates the commute as a weighted distance based on place location. Two data sets are compared, US National Guard data and US census data. Goal of this paper is to make conclusions about the commuting behavior of western residents through the use of these estimates, and therefore to provide a estimation method for distance commutes which can be used in further research. It is concluded that the radius method of estimation may be an over estimation, in particular in the western states. Since the non-western states are generally more homogeneously populated, this overestimation is not observed. It is recommended that the place location method be used for similar research, in particular studies dealing with western states. Suggestions are made for further research and recommendations are made for the US Army National Guard in regards to recruiting.

  5. Generalized Uncertainty Relation in the Non-commutative Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Chung, Won Sang

    2016-06-01

    In this paper the non-commutative quantum mechanics (NCQM) with the generalized uncertainty relations {Δ } x1 {Δ } x2 ≥ {θ}/{2}, {Δ} p1 {Δ } p2 ≥ {bar{θ}}/{2}, {Δ } xi {Δ } pi ≥ {hbar _{eff}}/{2} is discussed. Four each uncertainty relation, wave functions saturating each uncertainty relation are explicitly constructed. The unitary operators relating the non-commutative position and momentum operators to the commutative position and momentum operators are also investigated. We also discuss the uncertainty relation related to the harmonic oscillator.

  6. Gauge transformation and symmetries of the commutative multicomponent BKP hierarchy

    NASA Astrophysics Data System (ADS)

    Li, Chuanzhong

    2016-01-01

    In this paper, we defined a new multi-component B type Kadomtsev-Petviashvili (BKP) hierarchy that takes values in a commutative subalgebra of {gl}(N,{{C}}). After this, we give the gauge transformation of this commutative multicomponent BKP (CMBKP) hierarchy. Meanwhile, we construct a new constrained CMBKP hierarchy that contains some new integrable systems, including coupled KdV equations under a certain reduction. After this, the quantum torus symmetry and quantum torus constraint on the tau function of the commutative multi-component BKP hierarchy will be constructed.

  7. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  8. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  9. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  10. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  11. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A...

  12. 14 CFR 23.574 - Metallic damage tolerance and fatigue evaluation of commuter category airplanes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... evaluation of commuter category airplanes. 23.574 Section 23.574 Aeronautics and Space FEDERAL AVIATION... COMMUTER CATEGORY AIRPLANES Structure Fatigue Evaluation § 23.574 Metallic damage tolerance and fatigue evaluation of commuter category airplanes. For commuter category airplanes— (a) Metallic damage tolerance....

  13. 14 CFR 23.574 - Metallic damage tolerance and fatigue evaluation of commuter category airplanes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... evaluation of commuter category airplanes. 23.574 Section 23.574 Aeronautics and Space FEDERAL AVIATION... COMMUTER CATEGORY AIRPLANES Structure Fatigue Evaluation § 23.574 Metallic damage tolerance and fatigue evaluation of commuter category airplanes. For commuter category airplanes— (a) Metallic damage tolerance....

  14. Remarks on the New High-Efficiency Motor for an Electrical Bicycle

    NASA Astrophysics Data System (ADS)

    Kousaka, Takuji; Hasimoto, Naohide; Abe, Minoru

    There have been numerous theoretical and experimental investigations of the electrical bicycle, electrical vehicle, and so on. In this paper, we consider the new d-c compound motor for the electrical bicycle. This improvement maybe take positive advantage of compound moter in the electrical bicycle. As an illustrative example, we show the experimental results on the level ground. The experiments show that the proposed method is more higher efficiency for the electrical bicycle than conventional method.

  15. An international review of the frequency of single-bicycle crashes (SBCs) and their relation to bicycle modal share

    PubMed Central

    Schepers, Paul; Agerholm, Niels; Amoros, Emmanuelle; Benington, Rob; Bjørnskau, Torkel; Dhondt, Stijn; de Geus, Bas; Hagemeister, Carmen; Loo, Becky P Y; Niska, Anna

    2015-01-01

    Objectives To study cyclists’ share of transport modes (modal share) and single-bicycle crashes (SBCs) in different countries in order to investigate if the proportion of cyclist injuries resulting from SBCs is affected by variation in modal share. Methods A literature search identified figures (largely from western countries) on SBC casualties who are fatally injured, hospitalised or treated at an emergency department. Correlation and regression analyses were used to investigate how bicycle modal share is related to SBCs. Results On average, 17% of fatal injuries to cyclists are caused by SBCs. Different countries show a range of values between 5% and 30%. Between 60% and 95% of cyclists admitted to hospitals or treated at emergency departments are victims of SBCs. The proportion of all injured cyclists who are injured in SBCs is unrelated to the share of cycling in the modal split. The share of SBC casualties among the total number of road crash casualties increases proportionally less than the increase in bicycle modal share. Conclusions While most fatal injuries among cyclists are due to motor vehicle–bicycle crashes, most hospital admissions and emergency department attendances result from SBCs. As found in previous studies of cyclists injured in collisions, this study found that the increase in the number of SBC casualties is proportionally less than the increase in bicycle modal share. PMID:24408962

  16. Using magnetorheological fluids in an innovative hybrid bicycle damper

    NASA Astrophysics Data System (ADS)

    Shiao, Y. J.; Nguyen, T. S.

    2015-12-01

    Magnetorheological fluids are capable of changing their viscosity quickly. This can provide good controllability and fast dynamic response. A conventional passive suspension system with air spring or hydraulic damper has simple design and financial benefit for bicycles, but its operation is uncontrollable and non-adaptive. This paper presented a semi-active hybrid bicycle suspension system which combines conventional air spring and a new magnetorheological damping brake together to reduce vibration of a bicycle. A multi-layer magnetorheological brake and linkage mechanism are connected to bike fork to form the adaptive damping part of the innovative hybrid suspension system. The simulation results proved that the semi-active suspension system can reduce bike vibration effectively.

  17. Bicycling crash characteristics: An in-depth crash investigation study.

    PubMed

    Beck, Ben; Stevenson, Mark; Newstead, Stuart; Cameron, Peter; Judson, Rodney; Edwards, Elton R; Bucknill, Andrew; Johnson, Marilyn; Gabbe, Belinda

    2016-11-01

    The aim of this study was to describe the crash characteristics and patient outcomes of a sample of patients admitted to hospital following bicycle crashes. Injured cyclists were recruited from the two major trauma services for the state of Victoria, Australia. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from the Victorian State Trauma Registry (VSTR) and the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). 186 cyclists consented to participate in the study. Crashes commonly occurred during daylight hours and in clear weather conditions. Two-thirds of crashes occurred on-road (69%) and were a combination of single cyclist-only events (56%) and multi-vehicle crashes (44%). Of the multi-vehicle crashes, a motor vehicle was the most common impact partner (72%) and distinct pre-crash directional interactions were observed between the cyclist and motor vehicle. Nearly a quarter of on-road crashes occurred when the cyclist was in a marked bicycle lane. Of the 31% of crashes that were not on-road, 28 (15%) occurred on bicycle paths and 29 (16%) occurred in other locations. Crashes on bicycle paths commonly occurred on shared bicycle and pedestrian paths (83%) and did not involve another person or vehicle. Other crash locations included mountain bike trails (39%), BMX parks (21%) and footpaths (18%). While differences in impact partners and crash characteristics were observed between crashes occurring on-road, on bicycle paths and in other locations, injury patterns and severity were similar. Most cyclists had returned to work at 6 months post-injury, however only a third of participants reported a complete functional recovery. Further research is required to develop targeted countermeasures to address the risk factors identified in this study. PMID:27544886

  18. Bicycle shock absorption systems and energy expended by the cyclist.

    PubMed

    Nielens, Henri; Lejeune, Thierry

    2004-01-01

    Bicycle suspension systems have been designed to improve bicycle comfort and handling by dissipating terrain-induced energy. However, they may also dissipate the cyclist's energy through small oscillatory movements, often termed 'bobbing', that are generated by the pedalling movements. This phenomenon is a major concern for competitive cyclists engaged in events where most of the time is spent climbing, e.g. off-road cross-country races. An acceptable method to assess the overall efficacy of suspension systems would be to evaluate energy consumed by cyclists using different types of suspension systems. It could be assumed that any system that reduces metabolic expenditure for the cyclist would automatically lead to performance improvement. Unfortunately, only a limited number of studies have been conducted on that subject. Moreover, the conclusions that can be drawn from most of them are limited due to unsatisfactory statistical power, experimental protocols, measuring techniques and equipment. This review presents and discusses the most relevant results of studies that focused on mechanical simulations as well as on energy expenditure in relation to off-road bicycle suspension systems. Evidence in the literature suggests that cyclist-generated power that is dissipated by suspensions is minimal and probably negligible on most terrains. However, the scarce studies on the topic as well as the limitations in the conclusions that can be drawn from most of them indicate that we should remain cautious before supporting the use of dual suspension bicycles on all course types and for all cyclists. For example, it should be kept in mind that most cross-country racers still use front suspension bicycles. This might be explained by excessive cyclist-generated power dissipation at the high mechanical powers developed by elite cross-country cyclists that have not been studied in the literature. Finally, suspended bicycles are more comfortable. Moreover, the fact that suspension

  19. Bicycling crash characteristics: An in-depth crash investigation study.

    PubMed

    Beck, Ben; Stevenson, Mark; Newstead, Stuart; Cameron, Peter; Judson, Rodney; Edwards, Elton R; Bucknill, Andrew; Johnson, Marilyn; Gabbe, Belinda

    2016-11-01

    The aim of this study was to describe the crash characteristics and patient outcomes of a sample of patients admitted to hospital following bicycle crashes. Injured cyclists were recruited from the two major trauma services for the state of Victoria, Australia. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from the Victorian State Trauma Registry (VSTR) and the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). 186 cyclists consented to participate in the study. Crashes commonly occurred during daylight hours and in clear weather conditions. Two-thirds of crashes occurred on-road (69%) and were a combination of single cyclist-only events (56%) and multi-vehicle crashes (44%). Of the multi-vehicle crashes, a motor vehicle was the most common impact partner (72%) and distinct pre-crash directional interactions were observed between the cyclist and motor vehicle. Nearly a quarter of on-road crashes occurred when the cyclist was in a marked bicycle lane. Of the 31% of crashes that were not on-road, 28 (15%) occurred on bicycle paths and 29 (16%) occurred in other locations. Crashes on bicycle paths commonly occurred on shared bicycle and pedestrian paths (83%) and did not involve another person or vehicle. Other crash locations included mountain bike trails (39%), BMX parks (21%) and footpaths (18%). While differences in impact partners and crash characteristics were observed between crashes occurring on-road, on bicycle paths and in other locations, injury patterns and severity were similar. Most cyclists had returned to work at 6 months post-injury, however only a third of participants reported a complete functional recovery. Further research is required to develop targeted countermeasures to address the risk factors identified in this study.

  20. Characteristics of Bicycling as a Viable Component to Outdoor Adventure Programming.

    ERIC Educational Resources Information Center

    McArthur, Cynthia

    Bicycling is a valuable medium for outdoor experiential learning. Bicycling shares with other outdoor learning activities some common elements such as environmental contrast, physical activity, a small group context, and a self-reliant form of transportation. However, bicycling has several unique characteristics that set it apart from other common…

  1. Preventing Mental Retardation through Use of Bicycle Helmets. ARC Q&A #101-48.

    ERIC Educational Resources Information Center

    Arc, Arlington, TX.

    This fact sheet uses a question-and-answer format to summarize what is known about preventing mental retardation through use of bicycle helmets. Questions and answers address the following topics: the importance of bicycle helmets; the number of bike riders injured or killed each year in bicycle crashes (about 1,000 killed, over 500,000 people…

  2. 40 CFR 721.10635 - Alkyl maleimide substituted bicyclic olefin (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkyl maleimide substituted bicyclic... Specific Chemical Substances § 721.10635 Alkyl maleimide substituted bicyclic olefin (generic). (a... generically as alkyl maleimide substituted bicyclic olefin (PMN P-12-480) is subject to reporting under...

  3. 40 CFR 721.10635 - Alkyl maleimide substituted bicyclic olefin (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkyl maleimide substituted bicyclic... Specific Chemical Substances § 721.10635 Alkyl maleimide substituted bicyclic olefin (generic). (a... generically as alkyl maleimide substituted bicyclic olefin (PMN P-12-480) is subject to reporting under...

  4. Bicycle Training for Youth with Down Syndrome and Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    MacDonald, Megan; Esposito, Phil; Hauck, Janet; Jeong, Irully; Hornyak, Joseph; Argento, Angela; Ulrich, Dale A.

    2012-01-01

    Children with Down syndrome (DS) and autism spectrum disorders (ASD) frequently have difficulty riding a two-wheel bicycle. The purpose of this study was to investigate an intervention using an adapted bicycle and individualized instruction to teach 71 youth to ride a standard two-wheel bicycle. Youth with DS (n = 30) and ASD (n = 41) between the…

  5. Leptogenesis from a Non Commutative FRW Like Model

    SciTech Connect

    Mebarki, O.; Mebarki, N.; Aissaoui, H.

    2010-10-31

    A pure NCG leptonic asymmetry is obtained for particles propagating in a curved non commutative FRW universe. It is shown that because of the space-time deformation, an axial like symmetry is generated.

  6. On the renormalization of non-commutative field theories

    NASA Astrophysics Data System (ADS)

    Blaschke, Daniel N.; Garschall, Thomas; Gieres, François; Heindl, Franz; Schweda, Manfred; Wohlgenannt, Michael

    2013-01-01

    This paper addresses three topics concerning the quantization of non-commutative field theories (as defined in terms of the Moyal star product involving a constant tensor describing the non-commutativity of coordinates in Euclidean space). To start with, we discuss the Quantum Action Principle and provide evidence for its validity for non-commutative quantum field theories by showing that the equation of motion considered as insertion in the generating functional Z c [ j] of connected Green functions makes sense (at least at one-loop level). Second, we consider the generalization of the BPHZ renormalization scheme to non-commutative field theories and apply it to the case of a self-interacting real scalar field: Explicit computations are performed at one-loop order and the generalization to higher loops is commented upon. Finally, we discuss the renormalizability of various models for a self-interacting complex scalar field by using the approach of algebraic renormalization.

  7. Strong Planck constraints on braneworld and non-commutative inflation

    SciTech Connect

    Calcagni, Gianluca; Kuroyanagi, Sachiko; Ohashi, Junko; Tsujikawa, Shinji E-mail: skuro@rs.tus.ac.jp E-mail: shinji@rs.kagu.tus.ac.jp

    2014-03-01

    We place observational likelihood constraints on braneworld and non-commutative inflation for a number of inflaton potentials, using Planck, WMAP polarization and BAO data. Both braneworld and non-commutative scenarios of the kind considered here are limited by the most recent data even more severely than standard general-relativity models. At more than 95 % confidence level, the monomial potential V(φ)∝φ{sup p} is ruled out for p ≥ 2 in the Randall-Sundrum (RS) braneworld cosmology and, for p > 0, also in the high-curvature limit of the Gauss-Bonnet (GB) braneworld and in the infrared limit of non-commutative inflation, due to a large scalar spectral index. Some parameter values for natural inflation, small-varying inflaton models and Starobinsky inflation are allowed in all scenarios, although some tuning is required for natural inflation in a non-commutative spacetime.

  8. [INVESTIGATION OF BLOOD BIOCHEMICAL INDICES DURING BICYCLE ERGOMETRY].

    PubMed

    Davydov, B V; Stepanova, G P; Krivitsyna, Z A; Vorontsov, A L; Voronkov, Yu I

    2015-01-01

    Our investigations showed that physical work (bicycle ergometry) alters the biochemical status of male volunteers. On the 5th minute of bicycle endometry capillary blood looses significantly glucose and increases magnesium, phosphorus and particularly lactic acid. Creatine phosphokinase activity and trygliceride levels did not deviate much from baseline values. All the changes had a similar trend equally in the supine and sitting position. Therefore, biochemical investigations may complement essentially the physiological and neurophysiological tests of human adaptability to physical loads. The investigation utilized the dry chemistry technology of rapid biochemical diagnostics. PMID:26738302

  9. How fast can you go on a bicycle?

    NASA Astrophysics Data System (ADS)

    Dunning, R. B.

    2009-07-01

    The bicycle provides a context-rich problem accessible to students in a first-year physics course, encircling several core physics principles such as conservation of total energy and angular momentum, dissipative forces, and vectors. In this article, I develop a simple numerical model that can be used by any first-year physics student to investigate the maximum speed of a road bicycle under various real-world conditions. The model calculates speed as a function of time for a given set of input parameters, such as the rider's input power (delivered through the drive train to the rear wheel) and frontal surface area.

  10. Classical limits of quantum mechanics on a non-commutative configuration space

    SciTech Connect

    Benatti, Fabio; Gouba, Laure

    2013-06-15

    We consider a model of non-commutative quantum mechanics given by two harmonic oscillators over a non-commutative two dimensional configuration space. We study possible ways of removing the non-commutativity based on the classical limit context known as anti-Wick quantization. We show that removal of non-commutativity from the configuration space and from the canonical operators is not commuting operation.

  11. Non-commutativity, teleology and GRB time delay

    NASA Astrophysics Data System (ADS)

    Li, Miao; Pang, Yi; Wang, Yi

    2010-01-01

    We propose a model in which an energy-dependent time delay of a photon originates from space-time non-commutativity, the time delay is due to a non-commutative coupling between dilaton and photon. We predict that in our model, high energy photons with different momentum can either be delayed or superluminal, this may be related to a possible time delay reported by the Fermi LAT and Fermi GBM Collaborations.

  12. Electronically commutated serial-parallel switching for motor windings

    DOEpatents

    Hsu, John S.

    2012-03-27

    A method and a circuit for controlling an ac machine comprises controlling a full bridge network of commutation switches which are connected between a multiphase voltage source and the phase windings to switch the phase windings between a parallel connection and a series connection while providing commutation discharge paths for electrical current resulting from inductance in the phase windings. This provides extra torque for starting a vehicle from lower battery current.

  13. Advanced propfan analysis for the family of commuter airplanes

    NASA Technical Reports Server (NTRS)

    Swift, Gerald A.; Creighton, Tom; Haddad, Raphael; Hendrich, Louis; Hensley, Doug; Morgan, Louise; Russell, Mark

    1987-01-01

    Advanced propfans were selected to be used throughout the family of commuters. These propulsion systems offer a 25 to 28 percent fuel savings over comparably sized turbofans operating in the 1990s. A brief study of the propulsion systems available for the family of commuters is provided and the selection of the advanced turboprops justified. The propeller and engine designs and performance are discussed. The integration of these designs are examined. Also addressed is the noise considerations and constraints due to propfan installation.

  14. Non-commutativity and Local Indistinguishability of Quantum States

    PubMed Central

    Ma, Teng; Zhao, Ming-Jing; Wang, Yao-Kun; Fei, Shao-Ming

    2014-01-01

    We study the local indistinguishability problem of quantum states. By introducing an easily calculated quantity, non-commutativity, we present an criterion which is both necessary and sufficient for the local indistinguishability of a complete set of pure orthogonal product states. A constructive distinguishing procedure to obtain the concrete local measurements and classical communications is given. The non-commutativity of ensembles can be also used to characterize the quantumness for classical-quantum or quantum-classical correlated states. PMID:25208830

  15. What interventions increase commuter cycling? A systematic review

    PubMed Central

    Stewart, Glenn; Anokye, Nana Kwame; Pokhrel, Subhash

    2015-01-01

    Objective To identify interventions that will increase commuter cycling. Setting All settings where commuter cycling might take place. Participants Adults (aged 18+) in any country. Interventions Individual, group or environmental interventions including policies and infrastructure. Primary and secondary outcome measures A wide range of ‘changes in commuter cycling’ indicators, including frequency of cycling, change in workforce commuting mode, change in commuting population transport mode, use of infrastructure by defined populations and population modal shift. Results 12 studies from 6 countries (6 from the UK, 2 from Australia, 1 each from Sweden, Ireland, New Zealand and the USA) met the inclusion criteria. Of those, 2 studies were randomised control trials and the remainder preintervention and postintervention studies. The majority of studies (n=7) evaluated individual-based or group-based interventions and the rest environmental interventions. Individual-based or group-based interventions in 6/7 studies were found to increase commuter cycling of which the effect was significant in only 3/6 studies. Environmental interventions, however, had small but positive effects in much larger but more difficult to define populations. Almost all studies had substantial loss to follow-up. Conclusions Despite commuter cycling prevalence varying widely between countries, robust evidence of what interventions will increase commuter cycling in low cycling prevalence nations is sparse. Wider environmental interventions that make cycling conducive appear to reach out to hard to define but larger populations. This could mean that environmental interventions, despite their small positive effects, have greater public health significance than individual-based or group-based measures because those interventions encourage a larger number of people to integrate physical activity into their everyday lives. PMID:26275902

  16. The role of multilevel factors in geographic differences in bicycle crash risk: a prospective cohort study

    PubMed Central

    2013-01-01

    Background Regular cycling plays an important role in increasing physical activity levels but raises safety concerns for many people. While cyclists bear a higher risk of injury than most other types of road users, the risk differs geographically. Auckland, New Zealand’s largest urban region, has a higher injury risk than the rest of the country. This paper identified underlying factors at individual, neighbourhood and environmental levels and assessed their relative contribution to this risk differential. Methods The Taupo Bicycle Study involved 2590 adult cyclists recruited in 2006 and followed over a median period of 4.6 years through linkage to four national databases. The Auckland participants were compared with others in terms of baseline characteristics, crash outcomes and perceptions about environmental determinants of cycling. Cox regression modelling for repeated events was performed with multivariate adjustments. Results Of the 2554 participants whose addresses could be mapped, 919 (36%) resided in Auckland. The Auckland participants were less likely to be Māori but more likely to be socioeconomically advantaged and reside in an urban area. They were less likely to cycle for commuting and off-road but more likely to cycle in the dark and in a bunch, use a road bike and use lights in the dark. They had a higher risk of on-road crashes (hazard ratio: 1.47; 95% CI: 1.22, 1.76), of which 53% (95% CI: 20%, 72%) was explained by baseline differences, particularly related to cycling off-road, in the dark and in a bunch and residing in urban areas. They were more concerned about traffic volume, speed and drivers’ behaviour. Conclusions The excess crash risk in Auckland was explained by cycling patterns, urban residence and factors associated with the region’s car-dominated transport environment. PMID:24321134

  17. Bicycle Education, A New Dimension in 4-H Programs for 8-11 Year Olds: Designed into Three Teaching Units.

    ERIC Educational Resources Information Center

    Borst, William H.

    The three teaching units in this packet are designed to help children ages 8 to 11 enjoy, utilize, and safely ride bicycles by mastering skills and knowledge pertaining to their bicycles, their driving ability, and the traffic system. Unit I is concerned with the bicycle and its parts, various kinds of bicycles, and proper size and maintenance.…

  18. Unrecognized fatal liver injury caused by a bicycle handlebar.

    PubMed

    Spitz, D J

    1999-05-01

    Patterned injuries often remain unrecognized by emergency department personnel. Immediate recognition of a simple, superficial patterned injury may result in prompt and possibly life-saving treatment. A fall off a bicycle with a patterned abdominal bruise should suggest potentially life-threatening trauma. PMID:10337880

  19. Bicyclic C21 Terpenoids from the Marine Sponge Clathria compressa

    PubMed Central

    Gupta, Prasoon; Sharma, Upasana; Schulz, Thomas C.; McLean, Amanda B.; Robins, Allan J.; West, Lyndon M.

    2012-01-01

    Three new bicyclic C21 terpenoids, clathric acid (1) and two N-acyl taurine derivatives, clathrimides A (2) and B (3) were isolated from the marine sponge Clathria compressa. The structures of these compounds were elucidated by interpretation of spectroscopic data. Clathric acid showed mild antibacterial activity against several Gram-positive bacteria. PMID:22607472

  20. Utilizing the Bicycle for Non-Traditional Activities

    ERIC Educational Resources Information Center

    Maina, Michael P.; Maina, Julie Schlegel; Sebek, Ludek; Hoffmanova, Jana; Kane, Jennifer Jackson

    2012-01-01

    This article examines the bicycle as not simply a means of transportation or as an exercise device, but rather as a vehicle for teambuilding and problem solving activities within a physical education curriculum. The activities described in this article focus on bike-centered initiatives that foster creative problem solving. They have universal…

  1. Street Wise Part 2: Educating Children for Safe Bicycling

    ERIC Educational Resources Information Center

    Crider, Linda B.; Hall, Amanda K.

    2006-01-01

    This part of the "Street Wise" series incorporates essential bicycle safety skills into a one week bike unit, designed for 3rd through 6th graders. These skills require much repetition and practice but can help children develop safe traffic behaviors that save lives, such as stopping, scanning, signaling, street crossing, and avoiding hazards.…

  2. "Walking" Along a Free Rotating Bicycle Wheel (Round and Round)

    NASA Astrophysics Data System (ADS)

    Güémez, J.; Fiolhais, M.

    2015-02-01

    We describe the kinematics, dynamics, and also some energy issues related to Marta mouse's motion when she walks on top of a horizontal bicycle wheel, which is free to rotate like a merry-go-round, as presented recently by Paul Hewitt in the "Figuring Physics" section of this journal. The situation is represented in Fig. 1, which was taken from Ref. 1.

  3. "Walking" Along a Free Rotating Bicycle Wheel (Round and Round)

    ERIC Educational Resources Information Center

    Güémez, J.; Fiolhais, M.

    2015-01-01

    We describe the kinematics, dynamics, and also some energy issues related to Marta mouse's motion when she walks on top of a horizontal bicycle wheel, which is free to rotate like a merry-go-round, as presented recently by Paul Hewitt in the "Figuring Physics" section of this journal. The situation is represented in Fig. 1, which was…

  4. How Fast Can You Go on a Bicycle?

    ERIC Educational Resources Information Center

    Dunning, R. B.

    2009-01-01

    The bicycle provides a context-rich problem accessible to students in a first-year physics course, encircling several core physics principles such as conservation of total energy and angular momentum, dissipative forces, and vectors. In this article, I develop a simple numerical model that can be used by any first-year physics student to…

  5. Bicycle injuries: a matter of mechanism and age.

    PubMed

    Siman-Tov, Maya; Jaffe, Dena H; Peleg, Kobi

    2012-01-01

    Bicycle riding is a popular form of recreation with positive health and environmental effects. These road users are vulnerable to serious injuries, especially when motor vehicles are involved. The goal of this study was to characterize cyclist-related injuries according to motor vehicle involvement for adults versus children. A retrospective study was carried out using data from 11 trauma centers in the Israeli National Trauma Registry (2001-2007). Injuries were classified according to whether a motor vehicle was involved, and differences in injury characteristics were assessed for adults (18+ years) versus children (1-17 years). A total of 5529 patients were hospitalized for bicycle injuries, of whom 1765 were adults and 3764 were children. Thirty percent (n=1662) of all bicycle injuries involved motor vehicles, although the rate of injuries resulting in hospitalization was 37% among adults and 27% among children. Injury characteristics and hospital resource utilization differed substantially by age group. Cyclists struck by a motor vehicle presented with more severe injuries requiring more hospital resources and resulting in poorer outcomes than those not involved with motor vehicles. The interaction effect between motor vehicle involvement and age was significant for torso injuries and need for medical imaging. We found that injury characteristics, hospital resource utilization and health-related outcomes for bicycle injuries are highly dependent on patient's age and mechanism of injury. Effect modification of motor vehicle involvement by age may in part reflect physicians' attitudes toward pediatric imaging. The risks identified in this study should be used for preparedness and management of trauma hospitalizations from bicycle injuries. PMID:22062347

  6. Gate drive latching circuit for an auxiliary resonant commutation circuit

    NASA Technical Reports Server (NTRS)

    Delgado, Eladio Clemente (Inventor); Kheraluwala, Mustansir Hussainy (Inventor)

    1999-01-01

    A gate drive latching circuit for an auxiliary resonant commutation circuit for a power switching inverter includes a current monitor circuit providing a current signal to a pair of analog comparators to implement latching of one of a pair of auxiliary switching devices which are used to provide commutation current for commutating switching inverters in the circuit. Each of the pair of comparators feeds a latching circuit which responds to an active one of the comparators for latching the associated gate drive circuit for one of the pair of auxiliary commutating switches. An initial firing signal is applied to each of the commutating switches to gate each into conduction and the resulting current is monitored to determine current direction and therefore the one of the switches which is carrying current. The comparator provides a latching signal to the one of the auxiliary power switches which is actually conducting current and latches that particular power switch into an on state for the duration of current through the device. The latching circuit is so designed that the only time one of the auxiliary switching devices can be latched on is during the duration of an initial firing command signal.

  7. Bias Assessment of General Chemistry Analytes using Commutable Samples.

    PubMed

    Koerbin, Gus; Tate, Jillian R; Ryan, Julie; Jones, Graham Rd; Sikaris, Ken A; Kanowski, David; Reed, Maxine; Gill, Janice; Koumantakis, George; Yen, Tina; St John, Andrew; Hickman, Peter E; Simpson, Aaron; Graham, Peter

    2014-11-01

    Harmonisation of reference intervals for routine general chemistry analytes has been a goal for many years. Analytical bias may prevent this harmonisation. To determine if analytical bias is present when comparing methods, the use of commutable samples, or samples that have the same properties as the clinical samples routinely analysed, should be used as reference samples to eliminate the possibility of matrix effect. The use of commutable samples has improved the identification of unacceptable analytical performance in the Netherlands and Spain. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has undertaken a pilot study using commutable samples in an attempt to determine not only country specific reference intervals but to make them comparable between countries. Australia and New Zealand, through the Australasian Association of Clinical Biochemists (AACB), have also undertaken an assessment of analytical bias using commutable samples and determined that of the 27 general chemistry analytes studied, 19 showed sufficiently small between method biases as to not prevent harmonisation of reference intervals. Application of evidence based approaches including the determination of analytical bias using commutable material is necessary when seeking to harmonise reference intervals.

  8. Personal and behavioral factors associated with bicycling in adults from Curitiba, Paraná State, Brazil.

    PubMed

    Kienteka, Marilson; Reis, Rodrigo Siqueira; Rech, Cassiano Ricardo

    2014-01-01

    Bicycling is an important form of physical activity that can promote health benefits. The objective of this study was to analyze the association between personal and behavioral aspects in transportation bicycling and leisure time bicycling in adults. Data was drawn from a household survey involving 677 adults (53.1% female) in Curitiba, Paraná State, Brazil. The prevalence of bicycling was 11.2% for transportation and 16.7% for leisure. The frequency of leisure time bicycling was higher among men (PR = 2.08; p < 0.001), young people < 30 and adults aged between 30 and 39.9, bicycle owners (PR = 8.76; p < 0.001) and among the physically active. Transportation bicycling occurred more frequently among men (PR = 3.63; p < 0.001), individuals aged 30 to 39.9, those with a low socioeconomic status (PR = 5.00; p = 0.006), bicycle owners (PR = 10.2; p < 0.001) and individuals with a negative perception of their quality of life. The prevalence of bicycling is low in Curitiba considering its potential as a means of physical activity. Personal and behavioral factors were associated with each form of bicycling.

  9. A non-commutative framework for topological insulators

    NASA Astrophysics Data System (ADS)

    Bourne, C.; Carey, A. L.; Rennie, A.

    2016-04-01

    We study topological insulators, regarded as physical systems giving rise to topological invariants determined by symmetries both linear and anti-linear. Our perspective is that of non-commutative index theory of operator algebras. In particular, we formulate the index problems using Kasparov theory, both complex and real. We show that the periodic table of topological insulators and superconductors can be realized as a real or complex index pairing of a Kasparov module capturing internal symmetries of the Hamiltonian with a spectral triple encoding the geometry of the sample’s (possibly non-commutative) Brillouin zone.

  10. 77 FR 4326 - Announcement of Requirements and Registration for “Health Innovations in Commuting Challenge”

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ...: Notice. SUMMARY: The purpose of this challenge is to highlight the role of health data during commutes and how it may play a critical role in improving the health of commuters. The ``Health Innovations...

  11. Traffic conflicts on bicycle paths: a systematic observation of behaviour from video.

    PubMed

    van der Horst, A Richard A; de Goede, Maartje; de Hair-Buijssen, Stefanie; Methorst, Rob

    2014-01-01

    In The Netherlands, on bicycle paths, single-bicycle accidents, bicycle-bicycle and bicycle-moped accidents constitute a considerable share of all bicyclist injuries. Over three quarters of all hospitalised bicyclist victims in the Netherlands cannot be directly related to a crash with motorised traffic. As the usage of bicycle paths steadily increases, it is to be expected that safety on bicycle paths will become a major issue in the coming years in The Netherlands. A study was conducted into the behaviour of bicyclists and moped riders to improve traffic safety on bicycle paths. By behavioural observations with video, mutual conflicts and bicyclist behaviour on bicycle paths were recorded and analysed, among other things by means of the conflict observation method DOCTOR (Dutch Objective Conflict Technique for Operation and Research). The explorative phase of the study (phase 1), included two research locations, one in the city of Amsterdam and one in Eindhoven. The results gave guidance for a better understanding of the behaviour between different users of separate two-directional bicycle paths. An example includes the relationship between bicyclist-moped rider behaviour and the width of the bicycle path. For a condition with busy bicycle traffic in both directions the width of the bicycle path in Amsterdam (effectively 3.55m) is relatively narrow, whereas the bicycle path width in Eindhoven (>4.94m) appears to be sufficient to accommodate large flows of bicyclists. Because of a large flow of crossing pedestrians resulting in (severe) conflicts with bicyclists in Amsterdam, additional countermeasures to better control these interactions are needed. The DOCTOR conflict observation method from video appears to be applicable for conflicts between intersecting road users and for head-on conflicts on the bicycle path. Conflict situations between bicyclists in the same direction (constituting an important share of injury accidents on bicycle paths) require an

  12. Photochemical synthesis of nucleoside analogues from cyclobutanones: bicyclic and isonucleosides.

    PubMed

    Jaffer, Mileina; Ebead, Abdelaziz; Lee-Ruff, Edward

    2010-05-26

    The preparation of two nucleoside analogues are reported. Both syntheses involve a key photochemical ring-expansion of cyclobutanones to an oxacarbene and its subsequent scavenging by 6-chloropurine. The synthesis of a bicyclic (locked) purine starts from a oxabicycloheptanone with a hydroxymethyl pendant. The preparation of an isonucleoside uses a cyclobutanone with an alpha-substituted 6-chloropurine. Irradiation of the latter produces an isonucleoside and acyclic nucleoside analogues.

  13. Formation and Properties of a Bicyclic Silylated Digermene

    PubMed Central

    Hlina, Johann; Baumgartner, Judith; Marschner, Christoph; Albers, Lena; Müller, Thomas; Jouikov, Viatcheslav V

    2014-01-01

    In the presence of PMe3 or N-heterocyclic carbenes, the reaction of oligosilanylene dianions with GeCl2⋅dioxane gives germylene–base adducts. After base abstraction, the free germylenes can dimerize by formation of a digermene. An electrochemical and theoretical study of a bicyclic tetrasilylated digermene revealed formation of a comparably stable radical anion and a more reactive radical cation, which were characterized further by UV/Vis and ESR spectroscopy. PMID:24981992

  14. Survey of Bicycle Accidents Presenting in an Emergency Department

    PubMed Central

    Smith, N. A.; Yeats, I. F.

    1978-01-01

    A survey of bicycle accidents presenting in an emergency department was carried out over a 15 week period. Most accidents were the result of loss of control by the cyclist. Although soft tissue injuries predominated, followed by fractures, head injury was the single most common cause for admission to hospital (41.6%). These findings suggest that serious consideration be given to the use of protective headgear.

  15. A review of tibial spine fractures in bicycle injury.

    PubMed

    Nichols, J N; Tehranzadeh, J

    1987-01-01

    Nine tibial spine fractures were studied. Three of these nine cases included younger patients who fell from a bicycle and sustained an isolated avulsion fracture of the tibial spine. In all three cases, the medial tibial spines of the right knees were fractured. The other remaining five medial tibial fractures included two motorcycle and two automobile accidents, together with one basketball injury. One of the nine tibial spine fractures involved the lateral tibial spine.

  16. Associations between long commutes and subjective health complaints among railway workers in Norway.

    PubMed

    Urhonen, Terhi; Lie, Arve; Aamodt, Geir

    2016-12-01

    Commuting is an important aspect of daily life for many employees, but there is little knowledge of how this affects individual commuters' health and well-being. The authors investigated the relationship between commuting and subjective health complaints, using data from a web-based questionnaire. In a sample of 2126 railway employees, 644 (30.3%) had long commute times. A 29-item inventory was used to measure the number and degree of the subjective health complaints. Those who commuted 60 min or more each way were characterized by significantly higher numbers and degrees of subjective health complaints compared with their peers with short commutes. The mean number of complaints was 7.5 among the former group and 6.4 for the latter group (p = 0.009). In a regression model, in which the authors controlled for age, gender, education, self-rated health, and coping, the employees with long commutes reported more complaints than those with short commutes. Significant associations were found between those with long commutes and the number and degree of incidences of self-reported musculoskeletal pain, pseudo-neurologic complaints, and gastrointestinal problems. Commuters who had had long commutes for more than 10 years reported more gastrointestinal and musculoskeletal complaints than those with long commutes for less than 2 years. Also, commuters with long commutes spent less time with their families and leisure activities compared with those with short commutes. The authors conclude that the association between long commute times and higher levels of subjective health complaints should attract the attention of transport planners, employers, and public health policymaker.

  17. Associations between long commutes and subjective health complaints among railway workers in Norway.

    PubMed

    Urhonen, Terhi; Lie, Arve; Aamodt, Geir

    2016-12-01

    Commuting is an important aspect of daily life for many employees, but there is little knowledge of how this affects individual commuters' health and well-being. The authors investigated the relationship between commuting and subjective health complaints, using data from a web-based questionnaire. In a sample of 2126 railway employees, 644 (30.3%) had long commute times. A 29-item inventory was used to measure the number and degree of the subjective health complaints. Those who commuted 60 min or more each way were characterized by significantly higher numbers and degrees of subjective health complaints compared with their peers with short commutes. The mean number of complaints was 7.5 among the former group and 6.4 for the latter group (p = 0.009). In a regression model, in which the authors controlled for age, gender, education, self-rated health, and coping, the employees with long commutes reported more complaints than those with short commutes. Significant associations were found between those with long commutes and the number and degree of incidences of self-reported musculoskeletal pain, pseudo-neurologic complaints, and gastrointestinal problems. Commuters who had had long commutes for more than 10 years reported more gastrointestinal and musculoskeletal complaints than those with long commutes for less than 2 years. Also, commuters with long commutes spent less time with their families and leisure activities compared with those with short commutes. The authors conclude that the association between long commute times and higher levels of subjective health complaints should attract the attention of transport planners, employers, and public health policymaker. PMID:27660744

  18. Electric motor assisted bicycle as an aerobic exercise machine.

    PubMed

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise.

  19. Harvesting Energy from the Counterbalancing (Weaving) Movement in Bicycle Riding

    PubMed Central

    Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

    2012-01-01

    Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power. PMID:23112598

  20. Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

    PubMed

    Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

    2012-01-01

    Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power.

  1. [Mortality due to bicycle accidents in Pernambuco, Brazil].

    PubMed

    Galvão, Pauliana Valéria Machado; Pestana, Luciana Pinto; Pestana, Valter Mário; Spíndola, Michelline Oliveira Pedrosa; Campello, Reginaldo Inojosa Carneiro; de Souza, Eliane Helena Alvim

    2013-05-01

    The scope of this paper was to conduct a quantitative analysis of deaths resulting from bicycle accidents in the state of Pernambuco by studying secondary data between 2001 and 2010. The sample consisted of all the Deaths recorded in the Mortality Information System of the Unified Health System Database that reported bicycle accidents between 2001 and 2010. Descriptive measures were determined for all variables. Socio-demographic variables were paired with the basic cause of death in order to find a statistical correlation. In Pernambuco, the aforementioned information system recorded 517 deaths resulting from bicycle accidents, with greater frequency in men between 25 and 59 years of age, Afro-Brazilians, single and of unknown schooling. The mean age was 36.82 years (SD = 17.026), and the minimum and maximum age of 4 and 86 years old, respectively. The findings highlight the need for the creation of adequate infrastructure and effective legal measures to prevent traffic accidents involving this type of vehicle, relying on the evidence of distribution of cases in most Pernambuco municipalities.

  2. Electric motor assisted bicycle as an aerobic exercise machine.

    PubMed

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise. PMID:23366293

  3. Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.

    PubMed

    Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

    2012-01-01

    Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power. PMID:23112598

  4. Bicycle helmets are highly effective at preventing head injury during head impact: head-form accelerations and injury criteria for helmeted and unhelmeted impacts.

    PubMed

    Cripton, Peter A; Dressler, Daniel M; Stuart, Cameron A; Dennison, Christopher R; Richards, Darrin

    2014-09-01

    Cycling is a popular form of recreation and method of commuting with clear health benefits. However, cycling is not without risk. In Canada, cycling injuries are more common than in any other summer sport; and according to the US National Highway and Traffic Safety Administration, 52,000 cyclists were injured in the US in 2010. Head injuries account for approximately two-thirds of hospital admissions and three-quarters of fatal injuries among injured cyclists. In many jurisdictions and across all age levels, helmets have been adopted to mitigate risk of serious head injuries among cyclists and the majority of epidemiological literature suggests that helmets effectively reduce risk of injury. Critics have raised questions over the actual efficacy of helmets by pointing to weaknesses in existing helmet epidemiology including selection bias and lack of appropriate control for the type of impact sustained by the cyclist and the severity of the head impact. These criticisms demonstrate the difficulty in conducting epidemiology studies that will be regarded as definitive and the need for complementary biomechanical studies where confounding factors can be adequately controlled. In the bicycle helmet context, there is a paucity of biomechanical data comparing helmeted to unhelmeted head impacts and, to our knowledge, there is no data of this type available with contemporary helmets. In this research, our objective was to perform biomechanical testing of paired helmeted and unhelmeted head impacts using a validated anthropomorphic test headform and a range of drop heights between 0.5m and 3.0m, while measuring headform acceleration and Head Injury Criterion (HIC). In the 2m (6.3m/s) drops, the middle of our drop height range, the helmet reduced peak accelerations from 824g (unhelmeted) to 181g (helmeted) and HIC was reduced from 9667 (unhelmeted) to 1250 (helmeted). At realistic impact speeds of 5.4m/s (1.5m drop) and 6.3m/s (2.0m drop), bicycle helmets changed the

  5. 78 FR 75483 - Federal Travel Regulation (FTR); Relocation Allowances; Commuted Rate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-12

    ...] RIN 3090-AJ40 Federal Travel Regulation (FTR); Relocation Allowances; Commuted Rate AGENCY: Office of..., OGP, is providing a workable commuted rate to be used by agencies in determining a benchmark for... treated by Federal agencies as the commuted rate; that is, when a Federal employee moved his/her...

  6. 49 CFR 37.87 - Purchase or lease of used intercity and commuter rail cars.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... rail cars. 37.87 Section 37.87 Transportation Office of the Secretary of Transportation TRANSPORTATION....87 Purchase or lease of used intercity and commuter rail cars. (a) Except as provided elsewhere in this section, Amtrak or a commuter authority purchasing or leasing a used intercity or commuter...

  7. 49 CFR 37.87 - Purchase or lease of used intercity and commuter rail cars.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rail cars. 37.87 Section 37.87 Transportation Office of the Secretary of Transportation TRANSPORTATION....87 Purchase or lease of used intercity and commuter rail cars. (a) Except as provided elsewhere in this section, Amtrak or a commuter authority purchasing or leasing a used intercity or commuter...

  8. Research Refutes a Myth: Commuter Students Do Want to Be Involved.

    ERIC Educational Resources Information Center

    Likins, Jeanne M.

    1991-01-01

    Examined commuter college students' (n=326) involvement in the university community. Results refute myth that commuter college students do not want to be involved or feel a part of the university community. Claims debunking myths about commuter students is a prerequisite to providing effective services and programs for students today. (ABL)

  9. On the Need for Separate Commuter Programs: San Diego State Looks at Its Students.

    ERIC Educational Resources Information Center

    McCully, Barbie

    1980-01-01

    A self-assessment of commuter student programs and services at San Diego State University (SDSU) indicated that the university was doing well in meeting the needs of this population. For many years, most of the students at SDSU have been commuter students. Services and programs that were developed were created with the commuter student in mind.…

  10. 49 CFR 37.85 - Purchase or lease of new intercity and commuter rail cars.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rail cars. 37.85 Section 37.85 Transportation Office of the Secretary of Transportation TRANSPORTATION....85 Purchase or lease of new intercity and commuter rail cars. Amtrak or a commuter authority making a solicitation after August 25, 1990, to purchase or lease a new intercity or commuter rail car for use on...

  11. 49 CFR 37.85 - Purchase or lease of new intercity and commuter rail cars.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... rail cars. 37.85 Section 37.85 Transportation Office of the Secretary of Transportation TRANSPORTATION....85 Purchase or lease of new intercity and commuter rail cars. Amtrak or a commuter authority making a solicitation after August 25, 1990, to purchase or lease a new intercity or commuter rail car for use on...

  12. How To Give 'Em What They Want: Assessment Basics for Commuters.

    ERIC Educational Resources Information Center

    Rue, Penny

    1981-01-01

    Commuter students are often left out of college programs because their needs and schedules differ substantially from the traditional student for whom the programs are planned. Once the basic educational needs of the commuter student are being met, planners can focus on developing programs geared to other needs of the commuter such as personal…

  13. 49 CFR 37.85 - Purchase or lease of new intercity and commuter rail cars.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rail cars. 37.85 Section 37.85 Transportation Office of the Secretary of Transportation TRANSPORTATION....85 Purchase or lease of new intercity and commuter rail cars. Amtrak or a commuter authority making a solicitation after August 25, 1990, to purchase or lease a new intercity or commuter rail car for use on...

  14. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Commutation of payments to aliens and... FOR LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States...

  15. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 4 2013-04-01 2013-04-01 false Commutation of payments to aliens and... FOR LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States...

  16. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Commutation of payments to aliens and... FOR LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States...

  17. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Commutation of payments to aliens and... LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States...

  18. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false Commutation of payments to aliens and... FOR LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States...

  19. A perspective on non-commutative quantum gravity

    NASA Astrophysics Data System (ADS)

    Martins, Rachel A. D.

    2015-06-01

    In this paper, we present some of the concepts underlying a program of non-commutative quantum gravity and recall some of the results. This program includes a novel approach to spectral triple categorification and also a precise connection between Fell bundles and Connes' non-commutative geometry. Motivated by topics in quantization of the non-commutative standard model and introduction of algebraic techniques and concepts into quantum gravity (following for example Crane, Baez and Barrett), we define spectral C*-categories, which are deformed spectral triples in a sense made precise. This definition gives to representations of a C*-category on a small category of Hilbert spaces and bounded linear maps, the interpretation of a topological quantum field theory. The construction passes two mandatory tests: (i) there is a classical limit theorem reproducing a Riemannian spin manifold manifesting Connes' and Schücker's non-commutative counterpart of Einstein's equivalence principle, and (ii) there is consistency with the experimental fermion mass matrix. We also present an algebra invariant taking the form of a partition function arising from a C*-bundle dynamical system in connection with C*-subalgebra theory.

  20. Some Transportation Alternatives for Commuter Colleges and Universities.

    ERIC Educational Resources Information Center

    Hardwick, Mark W.; Kazlo, Martha P.

    This document is written in an effort to urge commuter colleges and universities to use their technical expertise in solving the automobile problem, which adds to the congestion and pollution in college communities. It has become a necessity that colleges and universities begin to explore ways to offer a variety of less expensive transportation…

  1. Active commuting to elementary school and adiposity: An observational study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Active commuting to school (ACS; walking or cycling to school) appears promising for decreasing children's obesity risk, although long-term studies are sparse. The aim was to examine whether kindergarten ACS was associated with fifth grade adiposity. This study was a secondary analysis of the Early ...

  2. 75 FR 13680 - Commutation of Sentence: Technical Change

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-23

    ... Bureau of Prisons 28 CFR Part 571 RIN 1120-AB54 Commutation of Sentence: Technical Change AGENCY: Bureau of Prisons, Justice. ACTION: Interim rule. SUMMARY: This document makes a minor technical change to... Sentence: Technical Change This document makes a minor technical change to the Bureau regulations...

  3. Commute alternatives systems handbook. Report for July 1993-June 1995

    SciTech Connect

    Winters, P.L.; Rudge, D.E.

    1995-08-01

    The Commute Alternative Handbook (CASH) provides a general introduction to Transportation Demand Management (TDM) that includes an overview of the national conditions which have led to increased TDM activities. This manual also describes various TDM strategies, implementation mechanisms and performance measurements.

  4. Analyses of School Commuting Data for Exposure Modeling Purposes

    EPA Science Inventory

    Human exposure models often make the simplifying assumption that school children attend school in the same Census tract where they live. This paper analyzes that assumption and provides information on the temporal and spatial distributions associated with school commuting. The d...

  5. FACTORS EFFECTING EXPOSURES TO VOCS DURING COMMUTING IN CALIFORNIA

    EPA Science Inventory

    On the average, Californian's spend between one and three hours each day commuting. The contribution from in-vehicle exposures to air toxics may be a significant component of total air exposure. Although pollutant concentration data are important for exposure assessments, onl...

  6. The Business Case for Commuter Benefits at Colleges and Universities

    ERIC Educational Resources Information Center

    Klavon, Patty

    2005-01-01

    Transportation and parking-related issues are common challenges for many colleges and universities today. Most institutions have far fewer parking spaces than they do commuters, and constructing and maintaining new parking facilities can cost hundreds of thousands of dollars. In this article, an Environmental Protection Agency representative…

  7. Regenerative Snubber For GTO-Commutated SCR Inverter

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E.; Edwards, Dean B.

    1992-01-01

    Proposed regenerative snubbing circuit substituted for dissipative snubbing circuit in inverter based on silicon controlled rectifiers (SCR's) commutated by gate-turn-off thyristor (GTO). Intended to reduce loss of power that occurs in dissipative snubber. Principal criteria in design: low cost, simplicity, and reliability.

  8. Compositions comprising a polypeptide having cellulolytic enhancing activity and a bicyclic compound and uses thereof

    DOEpatents

    Quinlan, Jason; Xu, Feng; Sweeney, Matthew

    2016-10-04

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a bicyclic compound. The present invention also relates to methods of using the compositions.

  9. Compositions comprising a polypeptide having cellulolytic enhancing activity and a bicycle compound and uses thereof

    SciTech Connect

    Xu, Feng; Sweeney, Matthew; Quinlan, Jason

    2015-06-16

    The present invention relates to compositions comprising: a polypeptide having cellulolytic enhancing activity and a bicyclic compound. The present invention also relates to methods of using the compositions.

  10. Longitudinal associations of active commuting with wellbeing and sickness absence

    PubMed Central

    Mytton, Oliver Tristan; Panter, Jenna; Ogilvie, David

    2016-01-01

    Objective Our aim was to explore longitudinal associations of active commuting (cycling to work and walking to work) with physical wellbeing (PCS-8), mental wellbeing (MCS-8) and sickness absence. Method We used data from the Commuting and Health in Cambridge study (2009 to 2012; n = 801) to test associations between: a) maintenance of cycling (or walking) to work over a one year period and indices of wellbeing at the end of that one year period; and b) associations between change in cycling (or walking) to work and change in indices of wellbeing. Linear regression was used for testing associations with PCS-8 and MCS-8, and negative binomial regression for sickness absence. Results After adjusting for sociodemographic variables, physical activity and physical limitation, those who maintained cycle commuting reported lower sickness absence (0.46, 95% CI: 0.14–0.80; equivalent to one less day per year) and higher MCS-8 scores (1.50, 0.10–2.10) than those who did not cycle to work. The association for sickness absence persisted after adjustment for baseline sickness absence. No significant associations were observed for PCS-8. Associations between change in cycle commuting and change in indices of wellbeing were not significant. No significant associations were observed for walking. Conclusions This work provides some evidence of the value of cycle commuting in improving or maintaining the health and wellbeing of adults of working age. This may be important in engaging employers in the promotion of active travel and communicating the benefits of active travel to employees. PMID:26740344

  11. Epidemic process over the commute network in a metropolitan area.

    PubMed

    Yashima, Kenta; Sasaki, Akira

    2014-01-01

    An understanding of epidemiological dynamics is important for prevention and control of epidemic outbreaks. However, previous studies tend to focus only on specific areas, indicating that application to another area or intervention strategy requires a similar time-consuming simulation. Here, we study the epidemic dynamics of the disease-spread over a commute network, using the Tokyo metropolitan area as an example, in an attempt to elucidate the general properties of epidemic spread over a commute network that could be used for a prediction in any metropolitan area. The model is formulated on the basis of a metapopulation network in which local populations are interconnected by actual commuter flows in the Tokyo metropolitan area and the spread of infection is simulated by an individual-based model. We find that the probability of a global epidemic as well as the final epidemic sizes in both global and local populations, the timing of the epidemic peak, and the time at which the epidemic reaches a local population are mainly determined by the joint distribution of the local population sizes connected by the commuter flows, but are insensitive to geographical or topological structure of the network. Moreover, there is a strong relation between the population size and the time that the epidemic reaches this local population and we are able to determine the reason for this relation as well as its dependence on the commute network structure and epidemic parameters. This study shows that the model based on the connection between the population size classes is sufficient to predict both global and local epidemic dynamics in metropolitan area. Moreover, the clear relation of the time taken by the epidemic to reach each local population can be used as a novel measure for intervention; this enables efficient intervention strategies in each local population prior to the actual arrival.

  12. Mass Commuting and Influenza Vaccination Prevalence in New York City: Protection in a Mixing Environment

    PubMed Central

    Levine, Burton; Wilcosky, Tim; Wagener, Diane; Cooley, Phillip

    2010-01-01

    Objective Assess influenza vaccination among commuters using mass transit in New York City (NYC). Methods We used the 2006 NYC Community Health Survey (CHS) to analyze the prevalence of influenza immunization by commuting behaviors and to understand what socioeconomic and geographic factors may explain any differences found. Results Vaccination prevalence is significantly lower for New Yorkers who commute on public transportation compared to other New Yorkers. This difference is largely attenuated after adjusting for socio-demographic characteristics and neighborhood of residence. Conclusions The analysis identified a low prevalence of immunization among commuters, and given the transmissibility in that setting, targeting commuters for vaccination campaigns may impede influenza spread. PMID:21218159

  13. Comparison of experimental data to a model for bicycle steady-state turning

    NASA Astrophysics Data System (ADS)

    Cain, Stephen M.; Perkins, Noel C.

    2012-08-01

    The steady-state turning of a bicycle arises when the bicycle/rider system negotiates a constant radius turn with constant speed and roll angle. This paper explores steady-state turning by employing a bicycle instrumented to measure steering torque, steering angle, and bicycle speed, acceleration, and angular velocity. We report data obtained from 134 trials using two subjects executing steady turns defined by nine different radii, three speeds, and three rider lean conditions. A model for steady-state turning, based on the Whipple bicycle model, is used to interpret the experimental results. Overall, the model explains 95.6% of the variability in the estimated bicycle roll angle, 99.4% of the variability in the measured steering angle, and 6.5% of the variability in the measured steering torque. However, the model explains 56.6% of the variability in steering torque for the subset of trials without exaggerated rider lean relative to the bicycle frame. Thus, the model, which assumes a rigid and non-leaning rider, reasonably predicts bicycle roll and steering angles for all rider lean conditions and steering torque without exaggerated rider lean. The findings demonstrate that lateral shifting of the bicycle/rider centre of mass strongly influences the steering torque, suggesting that rider lean plays an important role in bicycle control during steady-state turning. By contrast, the required steering angle is largely insensitive to rider lean, suggesting that the steering angle serves as a superior cue for bicycle control relative to the steering torque.

  14. Commuter rail state-of-the-art: A study of current systems. Final report

    SciTech Connect

    Shen, L.D.; Wu, J.W.

    1992-12-01

    The report documents the results of the state-of-the-art study on current commuter rail systems in the United States. Detailed information on operations, fare collection, stations, maintenance facilities, patronage, railcars, and feeder systems are presented. This commuter rail report is intended to provide a database of actual operation statistics for the 12 commuter rail systems in the United States. Statistics were collected on existing commuter rail services through Federal Transit Administration (FTA) reports, American Public Transit Association (APTA) and railroad industry publications. In addition, a survey was also conducted to collect the pertinent information on existing systems. A comparative analysis of commuter rail service with respect to other mass transit systems was conducted. New and proposed systems are also discussed. Current trends in commuter rail operations are presented. Startup costs for new systems were analyzed. This report found that many cities are considering commuter rail as a potential part of the solution to local transportation problems.

  15. Relationships Between Commuting and Social Capital Among Men and Women in Southern Sweden

    PubMed Central

    Håkansson, Carita; Jakobsson, Kristina

    2015-01-01

    The societal need for a mobile workforce increases time spent commuting and thus also the total workday. How this affects individual well-being and social life is, however, surprisingly little known. We investigated the relation between commuting time and mode, and social participation and general trust in other people as measures of social capital, using data from public health surveys conducted in 2004 and 2008 in Scania, Sweden: in all, 21,088 persons ages 18 to 65 and working at least 30 hr per week. Commuting by car was significantly associated with a higher prevalence of low social participation and low general trust compared with active commuting, and the association increased with the duration of commuting time. In contrast, public commuting was not significantly associated with decreased social capital measures except among long-duration commuters, who reported lower social participation. The overall pattern was similar for men and for women. PMID:26273107

  16. Discovery of bicyclic pyrazoles as class III histone deacetylase SIRT1 and SIRT2 inhibitors.

    PubMed

    Therrien, Eric; Larouche, Guillaume; Nguyen, Natalie; Rahil, Jubrail; Lemieux, Anne-Marie; Li, Zuomei; Fournel, Marielle; Yan, Theresa P; Landry, Anne-Julie; Lefebvre, Sylvain; Wang, James J; MacBeth, Kyle; Heise, Carla; Nguyen, Aaron; Besterman, Jeffrey M; Déziel, Robert; Wahhab, Amal

    2015-06-15

    A series of bicyclic pyrazole carboxamides was synthesized and tested for inhibitory activity against the class III deacetylase sirtuin enzymes. Moderate to low micromolar inhibitory activities were obtained against SIRT1 and SIRT2. These bicyclic pyrazole compounds represent a new class of sirtuin inhibitors with a preference for SIRT1 over SIRT2. PMID:25971769

  17. Safety effects of permanent running lights for bicycles: A controlled experiment.

    PubMed

    Madsen, J C O; Andersen, T; Lahrmann, H S

    2013-01-01

    Making the use of daytime running lights mandatory for motor vehicles is generally documented to have had a positive impact upon traffic safety. Improving traffic safety for bicyclists is a focal point in the road traffic safety work in Denmark. In 2004 and 2005 a controlled experiment including 3845 cyclists was carried out in Odense, Denmark in order to examine, if permanent running lights mounted to bicycles would improve traffic safety for cyclists. The permanent running lights were mounted to 1845 bicycles and the accident rate was recorded through 12 months for this treatment group and 2000 other bicyclists, the latter serving as a control group without bicycle running lights. The safety effect of the running lights is analysed by comparing incidence rates - number of bicycle accidents recorded per man-month - for the treatment group and the control group. The incidence rate, including all recorded bicycle accidents with personal injury to the participating cyclist, is 19% lower for cyclists with permanent running lights mounted; indicating that the permanent bicycle running light significantly improves traffic safety for cyclists. The study shows that use of permanent bicycle running lights reduces the occurrence of multiparty accidents involving cyclists significantly. In the study the bicycle accidents were recorded trough self-reporting on the Internet. Possible shortcomings and problems related to this accident recording are discussed and analysed. PMID:22884376

  18. Middle School Students and Bicycle Helmet Use: Knowledge, Attitudes, Beliefs, and Behaviors.

    ERIC Educational Resources Information Center

    Liller, Karen D.; Morissette, Brenda; Noland, Virginia; McDermott, Robert J.

    1998-01-01

    Examined middle school students' knowledge, attitudes, beliefs, and behaviors regarding bicycle helmet use. Surveys indicated that most rode bicycles but did not use helmets, despite understanding their protective capabilities, because of poor peer support and helmet design. There was a positive relationship between helmet ownership and use. Most…

  19. Recommendations for the assessment and design of young children's bicycles on the basis of anthropometric data.

    PubMed

    Donkers, P C; Toussaint, H M; Molenbroek, J F; Steenbekkers, L P

    1993-04-01

    Children's bicycles are the product most often involved in leisure accidents to children. One of the possible reasons for this might be a lack of fit between the dimensions of the bicycle and the dimensions of the child. In a project entitled KIMA-1, some 33 dimensions of 279 children (aged 2.5-5.5 years) were measured at seven infant welfare centres in the province of Zuid, Holland. These data were used to compare dimensions of children with dimensions of bicycles. Furthermore, the requirements regarding bicycle dimensions laid down in product safety acts of different countries were compared with both the results of KIMA-1 and some bicycles available in shops. It is concluded that maximum product safety and comfort of the bicycle are achieved when the bicycle is fitted to the dimensions of the child. Enhancement of this fitting process can be achieved by relating the dimensions of the bicycle to the stature rather than to the age of the child. The comparison of the KIMA-1 data to the dimensions laid down in product safety acts led to the conclusion that Dutch children are larger than the population on which the safety dimensions are based. Furthermore, secular changes in body dimensions call for a revision of the relevant safety dimensions in 10-15 years.

  20. The Bicycle Helmet Attitudes Scale: Using the Health Belief Model to Predict Helmet Use among Undergraduates

    ERIC Educational Resources Information Center

    Ross, Thomas P.; Ross, Lisa Thomson; Rahman, Annalise; Cataldo, Shayla

    2010-01-01

    Objective: This study examined bicycle helmet attitudes and practices of college undergraduates and developed the Bicycle Helmet Attitudes Scale, which was guided by the Health Belief Model (HBM; Rosenstock, 1974, in Becker MH, ed. "The Health Belief Model and Personal Health Behavior". Thorofare, NJ: Charles B. Slack; 1974:328-335) to predict…

  1. [A specific sign of the injury inflicted by the front wheel of a bicycle].

    PubMed

    Leonov, S V; Pinchuk, P V; Molchanov, D V

    2016-01-01

    The authors report the results of the comprehensive forensic medical expertise of the injury inflicted by the front wheel of a bicycle that revealed a new specific sign of the contact between the protruding part of the wheel of the bicycle (the brake disk) and the pedestrian's body. PMID:27070037

  2. 16 CFR Figure 8 to Part 1512 - Reflectorized Bicycle Wheel Rim Abrasion Test Device

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Reflectorized Bicycle Wheel Rim Abrasion Test Device 8 Figure 8 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Pt. 1512, Fig. 8 Figure 8 to Part...

  3. 16 CFR Figure 8 to Part 1512 - Reflectorized Bicycle Wheel Rim Abrasion Test Device

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Reflectorized Bicycle Wheel Rim Abrasion Test Device 8 Figure 8 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Pt. 1512, Fig. 8 Figure 8 to Part...

  4. 16 CFR Figure 8 to Part 1512 - Reflectorized Bicycle Wheel Rim Abrasion Test Device

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Reflectorized Bicycle Wheel Rim Abrasion Test Device 8 Figure 8 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Pt. 1512, Fig. 8 Figure 8 to Part...

  5. 16 CFR Figure 8 to Part 1512 - Reflectorized Bicycle Wheel Rim Abrasion Test Device

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Reflectorized Bicycle Wheel Rim Abrasion Test Device 8 Figure 8 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Pt. 1512, Fig. 8 Figure 8 to Part...

  6. 16 CFR Figure 8 to Part 1512 - Reflectorized Bicycle Wheel Rim Abrasion Test Device

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Reflectorized Bicycle Wheel Rim Abrasion Test Device 8 Figure 8 to Part 1512 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BICYCLES Pt. 1512, Fig. 8 Figure 8 to Part...

  7. Use of Adapted Bicycles on the Learning of Conventional Cycling by Children with Mental Retardation

    ERIC Educational Resources Information Center

    Burt, Tammy L.; Porretta, David L.; Klein, Richard E.

    2007-01-01

    This study investigated the use of adapted bicycles on the acquisition, maintenance, and generalization of conventional cycling by seven children with mild mental retardation. Feedback was used in addition to the adapted bicycles and consisted of pedal rate, head position, and steering participation. A multiple probe design was used. Participants…

  8. Envisioning Competence: Learning, Problem Solving, and Children at Work in the Exploratory Bicycle Shop

    ERIC Educational Resources Information Center

    Hammond, Charles Florian

    2010-01-01

    This study examines the conceptual learning and cognitive development processes of schoolchildren engaged in problem solving activities in a non-school, workplace setting known as the exploratory bicycle shop. The exploratory bike shop is a commercial bicycle shop: a) that has been adapted for combined retail and educational purposes and b) where…

  9. 77 FR 12761 - Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycle Route

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... National Park Service 36 CFR Part 7 RIN 1024-AE08 Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycle Route AGENCY: National Park Service, Interior. ACTION: Proposed rule. SUMMARY: The National Park Service (NPS) is proposing to designate the Hope Camp Trail as a bicycle...

  10. 77 FR 60050 - Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycling

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-02

    ... Hope Camp Trail as a bicycle route within Saguaro National Park (77 FR 12761). The proposed rule was... National Park Service 36 CFR Part 7 RIN 1024-AE08 Special Regulations; Areas of the National Park System, Saguaro National Park, Bicycling AGENCY: National Park Service, Interior. ACTION: Final rule....

  11. Bicycle ownership, use, and injury patterns among elementary schoolchildren

    PubMed Central

    Waller, Julian A

    1995-01-01

    Patterns of bicycle ownership and injury were studied over a four month period among over 6000 schoolchildren. Two thirds of the bikes owned were standard style and one third high rise. Boys more often had high rise bikes. Slightly over 2% of bike owners are injured annually, but no differences were found according to bike style either in injury rate or severity. Bike borrowing and riding double were common factors in the injury events. Injury from spokes and loss of control because of loose handlebars were identified as problems resulting from product design. PMID:9346042

  12. [Parameters of heart rate variability during bicycle ergometry test].

    PubMed

    Parnes, E Ia; Koshkina, E V; Krasnoselskiĭ, M Ia

    2003-01-01

    Short-term (5 min) heart rate variability (HRV) was studied before and during submaximal bicycle exercise tests in 27 patients with ischemic heart disease, 23 patients with hypertension and 9 healthy subjects. Low-frequency (0.04 to 0.15 Hz) and high-frequency (0.15 to 0.40 Hz) power components of HRV were significantly decreased during submaximal exercise. The level of load at which abrupt decrease of low-frequency components below 40 ms(2) occurred possibly reflected individual exercise tolerance. Episodes of myocardial ischemia were associated with pronounced decreases of low - frequency HRV components.

  13. Copper-catalyzed stereoselective aminoboration of bicyclic alkenes.

    PubMed

    Sakae, Ryosuke; Hirano, Koji; Satoh, Tetsuya; Miura, Masahiro

    2015-01-01

    A copper-catalyzed aminoboration of bicyclic alkenes, including oxa- and azabenzonorbornadienes, has been developed. With this method, amine and boron moieties are simultaneously introduced at an olefin with exo selectivity. Subsequent stereospecific transformations of the boryl group can provide oxygen- and nitrogen-rich cyclic molecules with motifs that may be found in natural products or pharmaceutically active compounds. Moreover, a catalytic asymmetric variant of this transformation was realized by using a copper complex with a chiral bisphosphine ligand, namely (R,R)-Ph-BPE. PMID:25404258

  14. Copper-catalyzed stereoselective aminoboration of bicyclic alkenes.

    PubMed

    Sakae, Ryosuke; Hirano, Koji; Satoh, Tetsuya; Miura, Masahiro

    2015-01-01

    A copper-catalyzed aminoboration of bicyclic alkenes, including oxa- and azabenzonorbornadienes, has been developed. With this method, amine and boron moieties are simultaneously introduced at an olefin with exo selectivity. Subsequent stereospecific transformations of the boryl group can provide oxygen- and nitrogen-rich cyclic molecules with motifs that may be found in natural products or pharmaceutically active compounds. Moreover, a catalytic asymmetric variant of this transformation was realized by using a copper complex with a chiral bisphosphine ligand, namely (R,R)-Ph-BPE.

  15. Federal Highway Administration University Course on Bicycle and Pedestrian Transportation. Publication No. FHWA-HRT-05-133

    ERIC Educational Resources Information Center

    Turner, Shawn; Sandt, Laura; Toole, Jennifer; Benz, Robert; Patten, Robert

    2006-01-01

    This "Student Workbook" contains 24 lessons of resource material that is intended for use in university courses on bicycle and pedestrian transportation. The lessons span a wide range of topics including an introduction to bicycling and walking issues, planning and designing for bicycle and pedestrian facilities, and supporting elements and…

  16. Can You Ride a Bicycle? The Ability to Ride a Bicycle Prevents Reduced Social Function in Older Adults With Mobility Limitation

    PubMed Central

    Sakurai, Ryota; Kawai, Hisashi; Yoshida, Hideyo; Fukaya, Taro; Suzuki, Hiroyuki; Kim, Hunkyung; Hirano, Hirohiko; Ihara, Kazushige; Obuchi, Shuichi; Fujiwara, Yoshinori

    2016-01-01

    Background The health benefits of bicycling in older adults with mobility limitation (ML) are unclear. We investigated ML and functional capacity of older cyclists by evaluating their instrumental activities of daily living (IADL), intellectual activity, and social function. Methods On the basis of interviews, 614 community-dwelling older adults (after excluding 63 participants who never cycled) were classified as cyclists with ML, cyclists without ML, non-cyclists with ML (who ceased bicycling due to physical difficulties), or non-cyclists without ML (who ceased bicycling for other reasons). A cyclist was defined as a person who cycled at least a few times per month, and ML was defined as difficulty walking 1 km or climbing stairs without using a handrail. Functional capacity and physical ability were evaluated by standardized tests. Results Regular cycling was documented in 399 participants, and 74 of them (18.5%) had ML; among non-cyclists, 49 had ML, and 166 did not. Logistic regression analysis for evaluating the relationship between bicycling and functional capacity revealed that non-cyclists with ML were more likely to have reduced IADL and social function compared to cyclists with ML. However, logistic regression analysis also revealed that the risk of bicycle-related falls was significantly associated with ML among older cyclists. Conclusions The ability and opportunity to bicycle may prevent reduced IADL and social function in older adults with ML, although older adults with ML have a higher risk of falls during bicycling. It is important to develop a safe environment for bicycling for older adults. PMID:26902165

  17. Rider trunk and bicycle pose estimation with fusion of force/inertial sensors.

    PubMed

    Zhang, Yizhai; Chen, Kuo; Yi, Jingang

    2013-09-01

    Estimation of human pose in physical human-machine interactions such as bicycling is challenging because of highly-dimensional human motion and lack of inexpensive, effective motion sensors. In this paper, we present a computational scheme to estimate both the rider trunk pose and the bicycle roll angle using only inertial and force sensors. The estimation scheme is built on a rider-bicycle dynamic model and the fusion of the wearable inertial sensors and the bicycle force sensors. We take advantages of the attractive properties of the robust force measurements and the motion-sensitive inertial measurements. The rider-bicycle dynamic model provides the underlying relationship between the force and the inertial measurements. The extended Kalman filter-based sensor fusion design fully incorporates the dynamic effects of the force measurements. The performance of the estimation scheme is demonstrated through extensive indoor and outdoor riding experiments. PMID:23629841

  18. Application of variable-sweep wings to commuter aircraft

    NASA Technical Reports Server (NTRS)

    Robins, A. W.; Beissner, F. L., Jr.; Lovell, W. A.; Price, J. E.; Turriiziani, R. V.; Washburn, F. F.

    1983-01-01

    The effects of using variable-sweep wings on the riding quality and mission-performance characteristics of commuter-type aircraft were studied. A fixed-wing baseline vehicle and a variable-sweep version of the baseline were designed and evaluated. Both vehicles were twin-turboprop, pressurized-cabin, 30-passenger commuter aircraft with identical mission requirements. Mission performance was calculated with and without various ride-quality constraints for several combinations of cruise altitude and stage lengths. The variable-sweep aircraft had a gross weight of almost four percent greater than the fixed-wing baseline in order to meet the design-mission requirements. In smooth air, the variable sweep configuration flying with low sweep had a two to three percent fuel-use penalty. However, the imposition of quality constraints in rough air can result in advantages in both fuel economy and flight time for the variable-sweep vehicle flying with high sweep.

  19. Commuting flows and conservation laws for noncommutative Lax hierarchies

    SciTech Connect

    Hamanaka, Masashi

    2005-05-01

    We discuss commuting flows and conservation laws for Lax hierarchies on noncommutative spaces in the framework of the Sato theory. On commutative spaces, the Sato theory has revealed essential aspects of the integrability for wide class of soliton equations which are derived from the Lax hierarchies in terms of pseudodifferential operators. Noncommutative extension of the Sato theory has been already studied by the author and Toda, and the existence of various noncommutative Lax hierarchies are guaranteed. In this paper, we present conservation laws for the noncommutative Lax hierarchies with both space-space and space-time noncommutativities and prove the existence of infinite number of conserved densities. We also give the explicit representations of them in terms of Lax operators. Our results include noncommutative versions of KP, KdV, Boussinesq, coupled KdV, Sawada-Kotera, modified KdV equation and so on.

  20. Determination of the flight equipment maintenance costs of commuter airlines

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Labor and materials costs associated with maintaining and operating 12 commuter airlines carrying an average of from 42 to 1,100 passengers daily in a variety of aircraft types were studied to determine the total direct maintenance cost per flight hour for the airframe, engine, and avionics and other instruments. The distribution of maintenance costs are analyzed for two carriers, one using turboprop aircraft and the other using piston engine aircraft.

  1. Rapid commutation duplexer with phase-related outputs

    NASA Astrophysics Data System (ADS)

    Roveda, R.; Cattarin, G.; Digregorio, C.; Parrucci, U.

    Design criteria and the realization of an X-band waveguide rapid commutation duplexer, in production, are presented. By means of a digital TTL command it is capable of operating in three different conditions: all the power is conveyed to a single output; the poweer is equally divided between two in-phase outputs; and it is equally divided between two counter-phase outputs. In a monopulse radar this permits the electronic scanning of the antenna beam.

  2. Semiclassical and quantum motions on the non-commutative plane

    NASA Astrophysics Data System (ADS)

    Baldiotti, M. C.; Gazeau, J. P.; Gitman, D. M.

    2009-10-01

    We study the canonical and the coherent state quantizations of a particle moving in a magnetic field on the non-commutative plane. Using a θ-modified action, we perform the canonical quantization and analyze the gauge dependence of the theory. We compare coherent states quantizations obtained through Malkin-Man'ko states and circular squeezed states. The relation between these states and the “classical” trajectories is investigated, and we present numerical explorations of some semiclassical quantities.

  3. Commutability of Cytomegalovirus WHO International Standard in Different Matrices

    PubMed Central

    Jones, Sara; Webb, Erika M.; Barry, Catherine P.; Choi, Won S.; Abravaya, Klara B.; Schneider, George J.

    2016-01-01

    Commutability of quantitative standards allows patient results to be compared across molecular diagnostic methods and laboratories. This is critical to establishing quantitative thresholds for use in clinical decision-making. A matrix effect associated with the 1st cytomegalovirus (CMV) WHO international standard (IS) was identified using the Abbott RealTime CMV assay. A commutability study was performed to compare the CMV WHO IS and patient specimens diluted in plasma and whole blood. Patient specimens showed similar CMV DNA quantitation values regardless of the diluent or extraction procedure used. The CMV WHO IS, on the other hand, exhibited a matrix effect. The CMV concentration reported for the WHO IS diluted in plasma was within the 95% prediction interval established with patient samples. In contrast, the reported DNA concentration of the CMV WHO IS diluted in whole blood was reduced approximately 0.4 log copies/ml, and values fell outside the 95% prediction interval. Calibrating the assay by using the CMV WHO IS diluted in whole blood would introduce a bias for CMV whole-blood quantitation; samples would be reported as having higher measured concentrations, by approximately 0.4 log IU/ml. Based on the commutability study with patient samples, the RealTime CMV assay was standardized based on the CMV WHO IS diluted in plasma. A revision of the instructions for use of the CMV WHO IS should be considered to alert users of the potential impact from the diluent matrix. The identification of a matrix effect with the CMV WHO IS underscores the importance of assessing commutability of the IS in order to achieve consistent results across methods. PMID:27030491

  4. Bicycle Riding: Impact on Lower Urinary Tract Symptoms and Erectile Function in Healthy Men

    PubMed Central

    Baek, Seok; Lee, Sun Young; Kim, Jong Min; Shin, Esther; Kam, Sin

    2011-01-01

    Purpose Recently, reports in the mass media have implicated that bicycle riding increases the risk of erectile dysfunction and prostatic diseases. So, we evaluate the impact of bicycle riding on erectile function and lower urinary tract symptoms (LUTS) in healthy general men. Methods From 26 June 2010 to 20 July 2010, we investigate degree of LUTS (voiding and storage symptoms), using International Continence Society-male Questionnaire (ICS-mQ) and erectile function using International Index of Erectile Function-5 Questionnaire (IIEF-5) in 5 work places (personnel of public office, hospital, university, etc.) of which bicycle riding club members were doing active club activities. Respondents, who participated in club activities for 6 months and longer, were classified as the bicycle club (142 men; age, 44.02±8.56). Ones who do not ride bicycles were classified as the control group (83 men; age, 42.13±7.85). People who were having the history of urological and other chronic diseases (diabetes, vascular disease, heart disease, etc) were excluded from both groups. Results Bicycle club is not significantly associated with increased prevalence of LUTS (bicycle club, 2.1 to 57.7% control, 4.8 to 73.5%) and erectile dysfunction (bicycle club, 46.1% control, 55.4%). The total mean score (storage/voiding/erectile function) of bicycle club (13.93±1.95/11.14±3.49/20.46±5.30) were not significantly different from control (14.35±2.49/11.52±3.38/20.40±4.07) (P=0.190 to 0.968). Conclusions These results suggested that bicycle riding as exercise or hobby has no negative effect on LUTS and erectile function in healthy general men, although this research data were limited to the questionnaire analysis. PMID:21811700

  5. [Relationships between settlement morphology transition and residents commuting energy consumption].

    PubMed

    Zhou, Jian; Xiao, Rong-Bo; Sun, Xiang

    2013-07-01

    Settlement morphology transition is triggered by rapid urbanization and urban expansion, but its relationships with residents commuting energy consumption remains ambiguous. It is of significance to understand the controlling mechanisms of sustainable public management policies on the energy consumption and greenhouse gases emission during the process of urban settlement morphology transition. Taking the Xiamen City of East China as a case, and by using the integrated land use and transportation modeling system TRANUS, a scenario analysis was made to study the effects of urban settlement morphology transition on the urban spatial distribution of population, jobs, and land use, and on the residents commuting energy consumption and greenhouse gasses emission under different scenarios. The results showed that under the Business As Usual (BAU) scenario, the energy consumption of the residents at the morning peak travel time was 54.35 tce, and the CO2 emission was 119.12 t. As compared with those under BAU scenario, both the energy consumption and the CO2 emission under the Transition of Settlement Morphology (TSM) scenario increased by 12%, and, with the implementation of the appropriate policies such as land use, transportation, and economy, the energy consumption and CO2 emission under the Transition of Settlement Morphology with Policies (TSMP) scenario reduced by 7%, indicating that urban public management policies could effectively control the growth of residents commuting energy consumption and greenhouse gases emission during the period of urban settlement morphology transition.

  6. Modelling the relation between income and commuting distance.

    PubMed

    Carra, Giulia; Mulalic, Ismir; Fosgerau, Mogens; Barthelemy, Marc

    2016-06-01

    We discuss the distribution of commuting distances and its relation to income. Using data from Denmark, the UK and the USA, we show that the commuting distance is (i) broadly distributed with a slow decaying tail that can be fitted by a power law with exponent γ ≈ 3 and (ii) an average growing slowly as a power law with an exponent less than one that depends on the country considered. The classical theory for job search is based on the idea that workers evaluate the wage of potential jobs as they arrive sequentially through time, and extending this model with space, we obtain predictions that are strongly contradicted by our empirical findings. We propose an alternative model that is based on the idea that workers evaluate potential jobs based on a quality aspect and that workers search for jobs sequentially across space. We also assume that the density of potential jobs depends on the skills of the worker and decreases with the wage. The predicted distribution of commuting distances decays as 1/r(3) and is independent of the distribution of the quality of jobs. We find our alternative model to be in agreement with our data. This type of approach opens new perspectives for the modelling of mobility. PMID:27278365

  7. Magnetic-free non-reciprocity based on staggered commutation

    PubMed Central

    Reiskarimian, Negar; Krishnaswamy, Harish

    2016-01-01

    Lorentz reciprocity is a fundamental characteristic of the vast majority of electronic and photonic structures. However, non-reciprocal components such as isolators, circulators and gyrators enable new applications ranging from radio frequencies to optical frequencies, including full-duplex wireless communication and on-chip all-optical information processing. Such components today dominantly rely on the phenomenon of Faraday rotation in magneto-optic materials. However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit. Here we demonstrate magnetic-free linear passive non-reciprocity based on the concept of staggered commutation. Commutation is a form of parametric modulation with very high modulation ratio. We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal–oxide–semiconductor integrated circuit for the first time. PMID:27079524

  8. The influence of body mass in endurance bicycling.

    PubMed

    Swain, D P

    1994-01-01

    Bicycling is a complex sport in which an athlete's energy cost is related to two principal forces: air resistance when traveling on flat terrain, and gravity when traveling uphill. Both wind tunnel data and physiological measurements suggest that air resistance scales as body mass to about the 1/3 power. Thus, large cyclists have only slightly greater frontal drags than small cyclists. If expressed relative to body mass, the frontal drag of small cyclists is considerably greater than that of large cyclists. The difference in frontal drag (energy cost) is not made up for by the advantage to small cyclists in relative VO2max (energy supply), since the mass exponent for drag (1/3) is closer to zero than that for VO2max (2/3). Thus, small cyclists should be at a disadvantage in flat time trials, which field data support. The energy cost of riding uphill slightly favors the large cyclist, because the weight of the bicycle represents a relatively smaller load than it does to a small cyclist. The mass exponent is 0.79. Since this exponent is greater than that for VO2max, the small cyclists have an advantage in climbing, which is supported by field data.

  9. Hybrid generalized Bosbach and Rie c̆ an states on non-commutative residuated lattices

    NASA Astrophysics Data System (ADS)

    Ma, Zhen Ming; Yang, Wei

    2016-08-01

    Generalized Bosbach and Rie c̆ an states, which are useful for the development of an algebraic theory of probabilistic models for commutative or non-commutative fuzzy logics, have been investigated in the literature. In this paper, a new way arising from generalizing residuated lattice-based filters from commutative case to non-commutative one is applied to introduce new notions of generalized Bosbach and Rie c̆ an states, which are called hybrid ones, on non-commutative residuated lattices is provided, and the relationships between hybrid generalized states and those existing ones are studied, examples show that they are different. In particular, two problems from L.C. Ciungu, G. Georgescu, and C. Mure, "Generalized Bosbach States: Part I" (Archive for Mathematical Logic 52 (2013):335-376) are solved, and properties of hybrid generalized states, which are similar to those on commutative residuated lattices, are obtained without the condition "strong".

  10. Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States

    PubMed Central

    Morency, Patrick; Miranda-Moreno, Luis F.; Willett, Walter C.; Dennerlein, Jack T.

    2013-01-01

    Objectives. We studied state-adopted bicycle guidelines to determine whether cycle tracks (physically separated, bicycle-exclusive paths adjacent to sidewalks) were recommended, whether they were built, and their crash rate. Methods. We analyzed and compared US bicycle facility guidelines published between 1972 and 1999. We identified 19 cycle tracks in the United States and collected extensive data on cycle track design, usage, and crash history from local communities. We used bicycle counts and crash data to estimate crash rates. Results. A bicycle facility guideline written in 1972 endorsed cycle tracks but American Association of State Highway and Transportation Officials (AASHTO) guidelines (1974–1999) discouraged or did not include cycle tracks and did not cite research about crash rates on cycle tracks. For the 19 US cycle tracks we examined, the overall crash rate was 2.3 (95% confidence interval = 1.7, 3.0) per 1 million bicycle kilometers. Conclusions. AASHTO bicycle guidelines are not explicitly based on rigorous or up-to-date research. Our results show that the risk of bicycle–vehicle crashes is lower on US cycle tracks than published crashes rates on roadways. This study and previous investigations support building cycle tracks. PMID:23678920

  11. Wobble of a racing bicycle with a rider hands on and hands off the handlebar

    NASA Astrophysics Data System (ADS)

    Klinger, Florian; Nusime, Julia; Edelmann, Johannes; Plöchl, Manfred

    2014-05-01

    So far fundamental papers on the understanding of the wobble mode at motorcycles have been published, but in contrast, little research has been published on the wobble mode at bicycles. Wobble denotes a characteristic unstable oscillatory mode dominated by oscillations of the front wheel about the steering axis. The wobble mode of a trekking bicycle at low speeds has already been analysed, where no influence of the rider's hands on the steering system is taken into account. The wobble mode of a racing bicycle at higher speeds has not been addressed in more detail so far. The paper points out the difference between a trekking bicycle and a racing bicycle in particular with respect to the wobble mode. Different geometry, mass and stiffness properties of both types of bicycles and different characteristic positions of the rider are considered. As the wobble at racing bicycles often occurs at high speeds, when riding down a grade with hands on a dropped handlebar, a passive rider model, that takes into account the movement of the rider's arms, is presented.

  12. Trade-offs between commuting time and health-related activities.

    PubMed

    Christian, Thomas J

    2012-10-01

    To further understand documented associations between obesity and urban sprawl, this research describes individuals' trade-offs between health-related activities and commuting time. A cross-section of 24,861 working-age individuals employed full-time and residing in urban counties is constructed from the American Time Use Survey (2003-2010). Data are analyzed using seemingly unrelated regressions to quantify health-related activity decreases in response to additional time spent commuting. Outcomes are total daily minutes spent in physical activity at a moderate or greater intensity, preparing food, eating meals with family, and sleeping. Commuting time is measured as all travel time between home and work and vice versa. The mean commuting time is 62 min daily, the median is 55 min, and 10.1% of workers commute 120 min or more. Spending an additional 60 min daily commuting above average is associated with a 6% decrease in aggregate health-related activities and spending an additional 120 min is associated with a 12% decrease. The greatest percentage of commuting time comes from sleeping time reductions (28-35%). Additionally, larger proportions of commuting time are taken from physical activity and food preparation relative to the mean commuting length: of 60 min spent commuting, 16.1% is taken from physical activity and 4.1% is taken from food preparation; of 120 min commuting, 20.3% is taken from physical activity and 5.6% is taken from food preparation. The results indicate that longer commutes are associated with behavioral patterns which over time may contribute to obesity and other poor health outcomes. These findings will assist both urban planners and researchers wishing to understand time constraints' impacts on health. PMID:22689293

  13. Cyclist safety on bicycle boulevards and parallel arterial routes in Berkeley, California.

    PubMed

    Minikel, Eric

    2012-03-01

    This study compares the safety of bicyclists riding on bicycle boulevards to those riding on parallel arterial routes in Berkeley, California. Literature on the impact of motor vehicle traffic characteristics on cyclist safety shows that high motor vehicle speeds and volumes and the presence of heavy vehicles are all detrimental to cyclist safety. This suggests that cyclists may be safer on side streets than on busy arterials. Bicycle boulevards-traffic-calmed side streets signed and improved for cyclist use-purport to offer cyclists a safer alternative to riding on arterials. Police-reported bicycle collision data and manually collected cyclist count data from bicycle boulevards and parallel arterial routes in Berkeley, California from 2003 to 2010 are used to test the hypothesis that Berkeley's bicycle boulevards have lower cyclist collision rates and a lower proportion of bicycle collisions resulting in severe injury. While no significant difference is found in the proportion of collisions that are severe, results show that collision rates on Berkeley's bicycle boulevards are two to eight times lower than those on parallel, adjacent arterial routes. The difference in collision rate is highly statistically significant, unlikely to be caused by any bias in the collision and count data, and cannot be easily explained away by self-selection or safety in numbers. Though the used dataset is limited and the study design is correlational, this study provides some evidence that Berkeley's bicycle boulevards are safer for cyclists than its parallel arterial routes. The results may be suggestive that, more generally, properly implemented bicycle boulevards can provide cyclists with a safer alternative to riding on arterials. PMID:22269506

  14. Potential health impact of switching from car to public transportation when commuting to work.

    PubMed

    Morabia, Alfredo; Mirer, Franklin E; Amstislavski, Tashia M; Eisl, Holger M; Werbe-Fuentes, Jordan; Gorczynski, John; Goranson, Chris; Wolff, Mary S; Markowitz, Steven B

    2010-12-01

    We assessed humidity-corrected particulate matter (PM(2.5)) exposure and physical activity (using global positioning system monitors and diaries) among 18 people who commuted by car to Queens College, New York, New York, for 5 days, and then switched to commuting for the next 5 days via public transportation. The PM(2.5) differed little between car and public transportation commutes (1.41 μg/M(3)·min; P = .226). Commuting by public transportation rather than by car increased energy expenditure (+124 kcal/day; P < .001) equivalent to the loss of 1 pound of body fat per 6 weeks.

  15. 14 CFR 135.398 - Commuter category airplanes performance operating limitations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... all commuter category airplanes notwithstanding their stated applicability to turbine-engine-powered... used, the elevation of the airport, the effective runway gradient, and ambient temperature, and...

  16. 14 CFR 135.398 - Commuter category airplanes performance operating limitations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... all commuter category airplanes notwithstanding their stated applicability to turbine-engine-powered... used, the elevation of the airport, the effective runway gradient, and ambient temperature, and...

  17. A low-cost FES exercise bicycle for training paraplegics at home.

    PubMed

    Mulder, A J; Hermens, H J; Janssen, F; Zilvold, G

    1989-01-01

    The success of FES exercise programmes for training paraplegic muscles at home depends highly upon the availability of reliable, easy-to-use and inexpensive training equipment. For endurance training, FES bicycle exercisers are well accepted. However, they are not suited for home use due to the high expense of commercially available equipment. This paper describes the development of a FES exercise bicycle for use at home. It consists of a standard bicycle ergometer with minimum modifications. The exerciser can be used by the patient sitting in the wheelchair, and may be used with any two-channel muscle stimulator.

  18. Continuous variable transmission and regenerative braking devices in bicycles utilizing magnetorheological fluids

    NASA Astrophysics Data System (ADS)

    Cheung, Wai Ming; Liao, Wei-Hsin

    2013-04-01

    The use of magnetorheological (MR) fluids in vehicles has been gaining popular recently due to its controllable nature, which gives automotive designers more dimensions of freedom in functional designs. However, not much attention has been paid to apply it to bicycles. This paper is aimed to study the feasibility of applying MR fluids in different dynamic parts of a bicycle such as the transmission and braking systems. MR continuous variable transmission (CVT) and power generator assisted in braking systems were designed and analyzed. Both prototypes were fabricated and tested to evaluate their performances. Experimental results showed that the proposed designs are promising to be used in bicycles.

  19. Performance Evaluation of the New High-Efficiency Motor for an Electrical Bicycle

    NASA Astrophysics Data System (ADS)

    Kousaka, Takuji; Hasimoto, Naohide; Abe, Minoru

    Over the past years, a great deal of studies have been devoted to electrical bicycle, electrical vehicle, and so on. In previous work, we studied a new d-c compound motor which is suitable for the electronic bicycle on the level ground. In contrast to this, this paper considers the performance evaluation of the new high-efficiency motor for an electrical bicycle in detail. We try to show the experimental results of several driving condition. This directly leads us to the conclusion that a new d-c compound motor is higher efficiency than conventional one.

  20. A low-cost FES exercise bicycle for training paraplegics at home.

    PubMed

    Mulder, A J; Hermens, H J; Janssen, F; Zilvold, G

    1989-01-01

    The success of FES exercise programmes for training paraplegic muscles at home depends highly upon the availability of reliable, easy-to-use and inexpensive training equipment. For endurance training, FES bicycle exercisers are well accepted. However, they are not suited for home use due to the high expense of commercially available equipment. This paper describes the development of a FES exercise bicycle for use at home. It consists of a standard bicycle ergometer with minimum modifications. The exerciser can be used by the patient sitting in the wheelchair, and may be used with any two-channel muscle stimulator. PMID:2786568

  1. Commuting alternatives in the United States: Recent trends and a look to the future. Final report, July 1993-December 1994

    SciTech Connect

    Ball, W.L.

    1994-12-01

    Commuting in the U.S. has evolved substantially over the past several decades, from the more traditional commute with a majority of destinations in the central business district to new travel patterns where commuting from suburb to suburb has grown to be the dominant commuting pattern. The report was prepared to assist in developing a through understanding of recent trends in commuting alternatives in the U.S. Using data from the Census, American Housing Survey (AHS), and the Nationwide Personal Transportation Study (NPTS), general trends in commuting are presented, including those related to mode choice, vehicle occupancy, departure time, travel time, and travel distance.

  2. [Prognostic significance of bicycle ergometry test in patients with myocarditis].

    PubMed

    Gavalova, R F; Borodina, V I

    1992-04-01

    A total of 42 patients with rheumatic carditis were examined in the acute-subacute period and following 3-5 years. Seventeen patients were diagnosed as having primary rheumatic carditis, 9 presented with tonsillogenic rheumatic carditis, and 16 had viral rheumatic carditis. The diagnosis of myocarditis was established on the basis of clinical, immunological, and virological findings. The study involved ECG, PhCG, PCG, and bicycle ergometer testing recordings. Groups of patients with good and poor prognosis were identified. Low threshold exercise, exercise-inadequate tachycardia, complex cardiac arrhythmias, phasic myocardial hypodynamic syndrome and volume exercise syndrome that are formed during performance are prognostically poor indicators. More profound electric and mechanic dysfunctions were observed in patients with tonsillogenic or viral myocarditis.

  3. Aromatic Esters of Bicyclic Amines as Antimicrobials against Streptococcus pneumoniae.

    PubMed

    de Gracia Retamosa, María; Díez-Martínez, Roberto; Maestro, Beatriz; García-Fernández, Esther; de Waal, Bas; Meijer, E W; García, Pedro; Sanz, Jesús M

    2015-11-01

    A double approach was followed in the search of novel inhibitors of the surface choline-binding proteins (CBPs) of Streptococcus pneumoniae (pneumococcus) with antimicrobial properties. First, a library of 49 rationally-designed esters of alkyl amines was screened for their specific binding to CBPs. The best binders, being esters of bicyclic amines (EBAs), were then tested for their in vitro effect on pneumococcal growth and morphology. Second, the efficiency of EBA-induced CBP inhibition was enhanced about 45,000-fold by multivalency effects upon synthesizing a poly(propylene imine) dendrimer containing eight copies of an atropine derivative. Both approaches led to compounds that arrest bacterial growth, dramatically decrease cell viability, and exhibit a protection effect in animal disease models, demonstrating that the pneumococcal CBPs are adequate targets for the discovery of novel antimicrobials that overcome the currently increasing antimicrobial resistance issues. PMID:26377931

  4. [Rehabilitation of aged patients with bicycle ergometer after coronary surgery].

    PubMed

    Lomama, E; Helft, G; Dufour, J C; Laudy, C; Monnet de Lorbeau, B; Vacheron, A

    1996-11-01

    This study was undertaken to assess the contraindications to rehabilitation by exercise testing on a bicycle ergometer and the tolerance of this procedure in elderly patients recovering from coronary surgery. One hundred and eighty-four patients aged over 65 years were included (Group I). The rehabilitation program consisted of exercise testing on admission period. The results were compared with those of 146 patients aged 65 or less (Group II). Twenty-six per cent of the elderly patients had a contraindications to this type of rehabilitation compared with only 4.8% in Group II. The main contraindications were extracardiac (21.7%), including infectious causes (4.3%), neuropsychiatric (3.3%), respiratory (2.7%) and rheumatological conditions (2.2%). Cardiac causes represented only 4.3% of the contraindications. In the patients undergoing the training program, the maximum power and the duration of exercise testing increased respectively from 81 +/- 17 to 97 +/- 21 watts (+21% ; p < 10(-3)) and 7 +/- 1.7 to 9 +/- 2 minutes (+28.6%, p < 10(-3)). The change in these parameters was comparable in the other group: 94.5+/- to 118 +/- 26 watts (+24.8% ; p < 10(-3)) and 8.5 +/- 1.9 to 10.9 +/- 2.4 minutes (+28.2% ; p < 10(-3)). On the other hand, the rate-pressure product decreased slightly in the elderly patients (-5.5% ; p = 0.07, compared with -13% in Group II, p = 0.001). Complications were rare: 1.6% of temporary interruption of a session (versus 0.6%). No serious complications were observed. The authors conclude that, after coronary surgery, the majority of elderly coronary patients can participate in physical training programs on bicycle ergometers without major complications. In the absence of contraindications, patients, and even elderly patients, should be encouraged to enroll for these programs after coronary bypass surgery.

  5. Analysis of School Commuting Data for Exposure Modeling Purposes

    SciTech Connect

    Xue, Jianping; McCurdy, Thomas; Burke, Janet; Bhaduri, Budhendra L; Liu, Cheng; Nutaro, James J; Patterson, Lauren A

    2010-01-01

    Human exposure models often make the simplifying assumption that school children attend school in the same census tract where they live. This paper analyzes that assumption and provides information on the temporal and spatial distributions associated with school commuting. The data were obtained using Oak Ridge National Laboratory s LandScan USA population distribution model (Bhaduri et al., 2007) applied to Philadelphia PA. It is a high-resolution model used to allocate individual school-aged children to both a home and school location, and to devise a minimum-time home-to school commuting path (called a trace) between the two locations. LandScan relies heavily on Geographic Information System (GIS) data. Our GIS analyses found that in Philadelphia: (1) about 32% of the students walk across 2 or more census tracts and 40% of them walk across 4 or more census blocks; (2) 60% drive across 4 or more census tracts going to school and 50% drive across 10 or more census blocks; (3) five-minute commuting time intervals result in misclassification as high as 90% for census blocks, 70% for block groups, and 50% for census tracts; (4) a one-minute time interval is needed to reasonably resolve time spent in the various census unit designations; (5) approximately 50% of both schoolchildren s homes and schools are located within 160 m of highly-traveled roads, and 64% of the schools are located within 200 m. These findings are very important when modeling school children s exposures, especially when ascertaining the impacts of near-roadway concentrations on their total daily body burden. Since many school children also travel along these streets and roadways to get to school, a majority of children in Philadelphia are in mobile-source dominated locations most of the day. We hypothesize that exposures of school children in Philadelphia to benzene and particulate matter will be much higher than if home and school locations and commuting paths at a 1-minute time resolution are

  6. On the essential spectrum of certain non-commutative oscillators

    SciTech Connect

    Parmeggiani, Alberto Venni, Alberto

    2013-12-15

    We show here that the spectrum of the family of non-commutative harmonic oscillators Q{sub (α,β)}{sup w}(x,D) for α,β∈R{sub +} in the range αβ = 1 is [0, +∞) and is entirely essential spectrum. The previous existing results concern the case αβ > 1 (case in which Q{sub (α,β)}{sup w}(x,D) is globally elliptic with a discrete spectrum whose qualitative properties are being extensively studied), and ours therefore extend the picture to the range of parameters αβ ⩾ 1.

  7. Size and seasonal distributions of airborne bioaerosols in commuting trains

    NASA Astrophysics Data System (ADS)

    Wang, Ya-Fen; Wang, Che-Hsu; Hsu, Kai-Lin

    2010-11-01

    Aerobiological studies in commuting trains in northern Taiwan were carried out from August, 2007 until July, 2008. Two six-stage (>7 μm, 4.7˜7 μm, 3.3˜4.7 μm, 2.1˜3.3 μm, 1.1˜2.1 μm, 0.65˜1.1 μm) cascade impactors of 400 orifices were used to collect viable bacteria and fungi, respectively. The levels of carbon monoxide (CO), carbon dioxide (CO 2), formaldehyde (HCHO), temperature, and relative humidity in the commuting trains were also recorded during the sampling period. Results show that bacterial concentrations ranged from 25 to 1530 CFU m -3, and averaged 417 CFU m -3. The fungal concentrations ranged from 45 to 1906 CFU m -3, and averaged 413 CFU m -3. Additionally, the highest fractions occurred in the fifth stage (1.1˜2.1 μm) for both bacteria and fungi. The respirable fractions, Rb and Rf, for bacteria and fungi were 62.8% and 81.4%, respectively, which are higher than those in other studies. Furthermore, the bacterial concentration reached its highest level in autumn, and its lowest level in winter. However, the fungal concentration was highest in spring and lowest in winter. Though the total bacterial or fungal concentration did not exceed the recommendation standard in Taiwan, the relatively high respirable fraction in commuting trains probably implies a higher adverse health risk for sensitive commuters. This study further conducted multiple regression analysis to determine the relationship of various stage fractions of airborne bacteria and fungi with indoor air pollutants (CO and HCHO) and environmental parameters (CO 2, temperature, and relative humidity). The correlation coefficients of multiple regression analysis for total bacteria and fungi concentrations with indoor air pollutants and environmental parameters were 0.707 ( p < 0.00376) and 0.612 ( p < 0.00471), respectively. There are currently no formally regulated laws for indoor air quality (IAQ) in Taiwan, and this preliminary study can provide references to the Taiwan

  8. Promoting health and safety for traveling and commuting employees.

    PubMed

    Pochat-Debroux, Sophia

    2008-09-01

    In a society that relies on a growing market economy and free enterprise, Americans spend inordinate time commuting and traveling for work. Aircraft and private vehicles are the two primary modes of work-related travel, with each having its own inherit risks and hazards. Although much has been written about international travel health, little has been published about protecting the health and safety of workers during domestic business travel. The intent of this article is to highlight the statistics associated with domestic business travel and present sound rationale for an inclusive and comprehensive domestic travel health and safety program for employees. PMID:18792614

  9. Using a micromachined magnetostatic relay in commutating a DC motor

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Wright, John A. (Inventor); Lilienthal, Gerald (Inventor)

    2004-01-01

    A DC motor is commutated by rotating a magnetic rotor to induce a magnetic field in at least one magnetostatic relay in the motor. Each relay is activated in response to the magnetic field to deliver power to at least one corresponding winding connected to the relay. In some cases, each relay delivers power first through a corresponding primary winding and then through a corresponding secondary winding to a common node. Specific examples include a four-pole, three-phase motor in which each relay is activated four times during one rotation of the magnetic rotor.

  10. Rotating turkeys and self-commutating artificial muscle motors

    NASA Astrophysics Data System (ADS)

    O'Brien, Benjamin M.; McKay, Thomas G.; Gisby, Todd A.; Anderson, Iain A.

    2012-02-01

    Electrostatic motors—first used by Benjamin Franklin to rotisserie a turkey—are making a comeback in the form of high energy density dielectric elastomer artificial muscles. We present a self-commutated artificial muscle motor that uses dielectric elastomer switches in the place of bulky external electronics. The motor simply requires a DC input voltage to rotate a shaft (0.73 Nm/kg, 0.24 Hz) and is a step away from hard metallic electromagnetic motors towards a soft, light, and printable future.

  11. Remote Sensing with Commutable Monolithic Laser and Detector

    PubMed Central

    2016-01-01

    The ubiquitous trend toward miniaturized sensing systems demands novel concepts for compact and versatile spectroscopic tools. Conventional optical sensing setups include a light source, an analyte interaction region, and a separate external detector. We present a compact sensor providing room-temperature operation of monolithic surface-active lasers and detectors integrated on the same chip. The differentiation between emitter and detector is eliminated, which enables mutual commutation. Proof-of-principle gas measurements with a limit of detection below 400 ppm are demonstrated. This concept enables a crucial miniaturization of sensing devices. PMID:27785455

  12. User satisfaction with commuter walk-in centres.

    PubMed

    Coster, Joanne; O'Cathain, Alicia; Nicholl, Jon; Salisbury, Chris

    2009-12-01

    Pilot commuter walk-in centres have been located close to national rail stations in major English cities, provided by private healthcare companies for the NHS, and offering access to doctors and nurses. This study used a survey to evaluate user satisfaction levels with this new service. Thirty-three per cent (1828/5574) of users completed a questionnaire. Centres demonstrated high levels of user satisfaction (69% 'very satisfied', 95% confidence interval = 58% to 79%) overall, but satisfaction was lower for some aspects of care such as waiting times. PMID:20875252

  13. Evaluating the effectiveness of on-street bicycle lane and assessing risk to bicyclists in Charlotte, North Carolina.

    PubMed

    Pulugurtha, Srinivas S; Thakur, Vidya

    2015-03-01

    The objectives of this manuscript are (1) to evaluate the effectiveness of on-street bicycle lane in reducing crashes involving bicyclists on urban roads, (2) to quantify and compare risk to bicyclists on road segments with and without on-street bicycle lane, (3) to evaluate the effect of on-street bicycle lane on other road network users (all crashes), and, (4) to assess the role of on-network characteristics (speed limit, the number of lanes, the width of on-street bicycle lane, the width of the right-most travel lane, and, the numbers of driveways, unsignalized approaches and signalized intersections per unit distance) on risk to bicyclists. Data for thirty-six segments with on-street bicycle lane and twenty-six segments without on-street bicycle lane in the city of Charlotte, North Carolina were extracted to compute and compare measures such as the number of bicycle crashes per center-lane mile, the number of bicycle crashes per annual million vehicle miles traveled (MVMT), the number of all crashes per center-lane mile, and the number of all crashes per MVMT. The results obtained from analysis indicate that bicyclists are three to four times at higher risk (based on traffic conditions) on segments without on-street bicycle lane than when compared to segments with on-street bicycle lane. An analysis conducted considering all crashes showed that on-street bicycle lanes do not have a statistically significant negative effect on overall safety. An increase in annual MVMT (exposure) and the number of signalized intersections per mile increases the number of bicycle crashes, while an increase in on-street bicycle lane width or right-most travel lane width (if on-street bicycle lane cannot be provided) decreases the number of bicycle crashes. Installing wider on-street bicycle lanes, limiting driveways to less than 50 per mile and unsignalized approaches to less than 10 per mile, increasing spacing between signalized intersections, and, facilitating wider right

  14. Evaluating the effectiveness of on-street bicycle lane and assessing risk to bicyclists in Charlotte, North Carolina.

    PubMed

    Pulugurtha, Srinivas S; Thakur, Vidya

    2015-03-01

    The objectives of this manuscript are (1) to evaluate the effectiveness of on-street bicycle lane in reducing crashes involving bicyclists on urban roads, (2) to quantify and compare risk to bicyclists on road segments with and without on-street bicycle lane, (3) to evaluate the effect of on-street bicycle lane on other road network users (all crashes), and, (4) to assess the role of on-network characteristics (speed limit, the number of lanes, the width of on-street bicycle lane, the width of the right-most travel lane, and, the numbers of driveways, unsignalized approaches and signalized intersections per unit distance) on risk to bicyclists. Data for thirty-six segments with on-street bicycle lane and twenty-six segments without on-street bicycle lane in the city of Charlotte, North Carolina were extracted to compute and compare measures such as the number of bicycle crashes per center-lane mile, the number of bicycle crashes per annual million vehicle miles traveled (MVMT), the number of all crashes per center-lane mile, and the number of all crashes per MVMT. The results obtained from analysis indicate that bicyclists are three to four times at higher risk (based on traffic conditions) on segments without on-street bicycle lane than when compared to segments with on-street bicycle lane. An analysis conducted considering all crashes showed that on-street bicycle lanes do not have a statistically significant negative effect on overall safety. An increase in annual MVMT (exposure) and the number of signalized intersections per mile increases the number of bicycle crashes, while an increase in on-street bicycle lane width or right-most travel lane width (if on-street bicycle lane cannot be provided) decreases the number of bicycle crashes. Installing wider on-street bicycle lanes, limiting driveways to less than 50 per mile and unsignalized approaches to less than 10 per mile, increasing spacing between signalized intersections, and, facilitating wider right

  15. An improved multi-value cellular automata model for heterogeneous bicycle traffic flow

    NASA Astrophysics Data System (ADS)

    Jin, Sheng; Qu, Xiaobo; Xu, Cheng; Ma, Dongfang; Wang, Dianhai

    2015-10-01

    This letter develops an improved multi-value cellular automata model for heterogeneous bicycle traffic flow taking the higher maximum speed of electric bicycles into consideration. The update rules of both regular and electric bicycles are improved, with maximum speeds of two and three cells per second respectively. Numerical simulation results for deterministic and stochastic cases are obtained. The fundamental diagrams and multiple states effects under different model parameters are analyzed and discussed. Field observations were made to calibrate the slowdown probabilities. The results imply that the improved extended Burgers cellular automata (IEBCA) model is more consistent with the field observations than previous models and greatly enhances the realism of the bicycle traffic model.

  16. Synthesis and screening of bicyclic carbohydrate-based compounds: a novel type of antivirals.

    PubMed

    Van Hoof, Steven; Ruttens, Bart; Hubrecht, Idzi; Smans, Gert; Blom, Petra; Sas, Benedikt; Van hemel, Johan; Vandenkerckhove, Jan; Van der Eycken, Johan

    2006-03-15

    A small library of bicyclic carbohydrate derivatives was synthesized and screened. A strong and selective activity against cytomegalovirus was found. Structure-activity relationship for this new type of antivirals is discussed.

  17. The effects of prompting and reinforcement on safe behavior of bicycle and motorcycle riders.

    PubMed

    Okinaka, Takeru; Shimazaki, Tsuneo

    2011-01-01

    A reversal design was used to evaluate the effects of vocal and written prompts as well as reinforcement on safe behavior (dismounting and walking bicycles or motorcycles on a sidewalk) on a university campus. Results indicated that an intervention that consisted of vocal and written prompts and reinforcement delivered by security guards was effective at increasing safe behavior exhibited by bicycle and motorcycle riders. No differences were observed between vehicle type or gender with regard to engagement in safe behavior.

  18. Bicycling injury hospitalisation rates in Canadian jurisdictions: analyses examining associations with helmet legislation and mode share

    PubMed Central

    Teschke, Kay; Koehoorn, Mieke; Shen, Hui; Dennis, Jessica

    2015-01-01

    Objectives The purpose of this study was to calculate exposure-based bicycling hospitalisation rates in Canadian jurisdictions with different helmet legislation and bicycling mode shares, and to examine whether the rates were related to these differences. Methods Administrative data on hospital stays for bicycling injuries to 10 body region groups and national survey data on bicycling trips were used to calculate hospitalisation rates. Rates were calculated for 44 sex, age and jurisdiction strata for all injury causes and 22 age and jurisdiction strata for traffic-related injury causes. Inferential analyses examined associations between hospitalisation rates and sex, age group, helmet legislation and bicycling mode share. Results In Canada, over the study period 2006–2011, there was an average of 3690 hospitalisations per year and an estimated 593 million annual trips by bicycle among people 12 years of age and older, for a cycling hospitalisation rate of 622 per 100 million trips (95% CI 611 to 633). Hospitalisation rates varied substantially across the jurisdiction, age and sex strata, but only two characteristics explained this variability. For all injury causes, sex was associated with hospitalisation rates; females had rates consistently lower than males. For traffic-related injury causes, higher cycling mode share was consistently associated with lower hospitalisation rates. Helmet legislation was not associated with hospitalisation rates for brain, head, scalp, skull, face or neck injuries. Conclusions These results suggest that transportation and health policymakers who aim to reduce bicycling injury rates in the population should focus on factors related to increased cycling mode share and female cycling choices. Bicycling routes designed to be physically separated from traffic or along quiet streets fit both these criteria and are associated with lower relative risks of injury. PMID:26525719

  19. Teaching children about bicycle safety: an evaluation of the New Jersey Bike School program.

    PubMed

    Lachapelle, Ugo; Noland, Robert B; Von Hagen, Leigh Ann

    2013-03-01

    There are multiple health and environmental benefits associated with increasing bicycling among children. However, the use of bicycles is also associated with severe injuries and fatalities. In order to reduce bicycle crashes, a bicycling education program was implemented in selected New Jersey schools and summer camps as part of the New Jersey Safe Routes to School Program. Using a convenience sample of participants to the program, an opportunistic study was designed to evaluate the effectiveness of two bicycle education programs, the first a more-structured program delivered in a school setting, with no on-road component, and the other a less structured program delivered in a summer camp setting that included an on-road component. Tests administered before and after training were designed to assess knowledge acquired during the training. Questions assessed children's existing knowledge of helmet use and other equipment, bicycle safety, as well as their ability to discriminate hazards and understand rules of the road. Participating children (n=699) also completed a travel survey that assessed their bicycling behavior and their perception of safety issues. Response to individual questions, overall pre- and post-training test scores, and changes in test scores were compared using comparison of proportion, t-tests, and ordinary least-squares (OLS) regression. Improvements between the pre-training and post-training test are apparent from the frequency distribution of test results and from t-tests. Both summer camps and school-based programs recorded similar improvements in test results. Children who bicycled with their parents scored higher on the pre-training test but did not improve as much on the post-training test. Without evaluating long-term changes in behavior, it is difficult to ascertain how successful the program is on eventual behavioral and safety outcomes.

  20. Wheelies and Headers, or How to Keep Both Bicycle Wheels on the Ground

    NASA Astrophysics Data System (ADS)

    Wehrbein, William M.

    2004-01-01

    A "wheelie" is when a bicycle is ridden with its front wheel lifted from the ground. Riding the bicycle in a way to lift the rear wheel off the ground might lead to the cyclist tumbling over the handlebars, called a "header." Other colorful terms for this situation are "endo" (short for "end-over-end") and "face plant" (for landing face first on the ground). Let's determine the conditions required in order to keep both tires touching the ground at all times.

  1. THE EFFECTS OF PROMPTING AND REINFORCEMENT ON SAFE BEHAVIOR OF BICYCLE AND MOTORCYCLE RIDERS

    PubMed Central

    Okinaka, Takeru; Shimazaki, Tsuneo

    2011-01-01

    A reversal design was used to evaluate the effects of vocal and written prompts as well as reinforcement on safe behavior (dismounting and walking bicycles or motorcycles on a sidewalk) on a university campus. Results indicated that an intervention that consisted of vocal and written prompts and reinforcement delivered by security guards was effective at increasing safe behavior exhibited by bicycle and motorcycle riders. No differences were observed between vehicle type or gender with regard to engagement in safe behavior. PMID:21941403

  2. Physiological alterations consequent to 20-week conditioning programs of bicycling, tennis, and jogging.

    PubMed

    Wilmore, J H; Davis, J A; O'Brien, R S; Vodak, P A; Walder, G R; Amsterdam, E A

    1980-01-01

    This study investigated the efficacy of free-wheel bicycling and tennis as endurance conditioning activities. The subjects were 38 sedentary, middle-aged male volunteers, who were randomly assigned to one of four groups: bicyling (N=9); tennis (N=10); jogging (N=9); and control (N=10). Each subject was tested twice at the beginning and once at the conclusion of the 20-week study. Each training group exercised 3 days/week for 30 min/day, following 15 minutes of formal warm-up. The bicycling, tennis and jogging groups had an average attendance of 3.0, 2.7, and 2.8 days/week, and maintained theri exercise intensity at 83, 65, and 85% of HR max respectively. Using analysis of covariance, only the bicycle and jogging groups significantly increased treadmill Vo2max (14.8 and 13.3% respectively) even though there was a 5.7% improvement for the tennis group. The control group did not change. Vo2max was also assessed on a cycle ergometer for the bicycle and jogging groups, and increased significantly by 17.4 and 14.0% respectively, thus, specificity of the training response was not identified. VEmax increased significantly in the bicycling and jogging groups, while resting blood pressure did not change for any of the four groups. Relative to body composition, only the bicycle group increased lean body weight. The bicycle and jogging groups had substantial decreases in relative and absolute body fat, but these changes were not statistically significant due to changes in the control group. In conclusion, bicycling and jogging appear to provide comparable physiological benefits. Tennis produced only modest increases in endurance capacity but, since the duration of each training session was only 30 to 50% of a typical time period for playing tennis, the results of the present study may, in fact, be underestimating changes in Vo2max due to the interaction of intensity and duration in facilitating change.

  3. [Impact of commuting on partnership and family life. A literature review of the current state of research with special emphasis on commuter marriages].

    PubMed

    Häfner, Steffen

    2011-01-01

    Because of modern working conditions, for many people commuting has increasingly become a necessity with many consequences for their health as well as for their family life and partnership. To date, little research has been done concerning the impact of this modern lifestyle on partnership and family life, particularly on dual-career couples and long-distance commuters. The results of a literature review are presented based on age, sex, family cycle and consequences for children; research questions are formulated. Sex-specific differences seem to be especially important, confirming the "household responsibility hypothesis." The commuter marriage as a new lifestyle seems to have become a coping mechanism for the increasing necessity in our society to commute.

  4. Commuting mode and pulmonary function in Shanghai, China.

    PubMed

    Gaffney, Adam W; Hang, Jing-Qing; Lee, Mi-Sun; Su, Li; Zhang, Feng-Ying; Christiani, David C

    2016-03-01

    Exposure to air pollution can be particularly high during commuting and may depend on the mode of transportation. We investigated the impact of commuting mode on pulmonary function in Shanghai, China.The Shanghai Putuo Study is a cross-sectional, population-based study. Our primary outcomes were forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) % predicted, and the secondary outcome was spirometric airflow obstruction. We tested the association between mode of transportation and these outcomes after adjusting for confounders.The study population consisted of 20 102 subjects. After adjusting for confounders, the change (95% CI) in FEV1 was -2.15% pred (-2.88- -1.42% pred) among pedestrians, -1.32% pred (-2.05- -0.59% pred) among those taking buses without air conditioning, -1.33% pred (-2.05- -0.61% pred) among those taking buses with air conditioning and -2.83% pred (-5.56- -0.10% pred) among those using underground railways, as compared to cyclists (the reference group). The effects of mode on FVC % predicted were in the same direction. Private car use had a significant protective effect on FVC % predicted and the risk of airflow obstruction (defined by Global Initiative for Chronic Obstructive Lung Disease but not by lower limit of normal criteria).Mode of transportation is associated with differences in lung function, which may reflect pollution levels in different transportation microenvironments. PMID:26541519

  5. Vehicle emissions during children's school commuting: impacts of education policy.

    PubMed

    Marshall, Julian D; Wilson, Ryan D; Meyer, Katie L; Rajangam, Santhosh K; McDonald, Noreen C; Wilson, Elizabeth J

    2010-03-01

    We explore how school policies influence the environmental impacts of school commutes. Our research is motivated by increased interest in school choice policies (in part because of the U.S. "No Child Left Behind" Act) and in reducing bus service to address recent budget shortfalls. Our analysis employs two samples of elementary-age children, age 5-12: a travel survey (n = 1246 respondents) and a school enrollment data set (n = 19,655 students). Multinomial logistic regression modeled the determinants of travel mode (automobile, school bus, and walking; n = 803 students meeting selection criteria). Travel distance has the single greatest effect on travel mode, though school choice, trip direction (to- or from-school), and grade play a role. Several policies were investigated quantitatively to predict the impact on school travel, vehicle emissions, and costs. We find that eliminating district-wide school choice (i.e., returning to a system with neighborhood schools only) would have significant impacts on transport modes and emissions, whereas in many cases proposed shifts in school choice and bus-provision policies would have only modest impacts. Policies such as school choice and school siting may conflict with the goal of increasing rates of active (i.e., nonmotorized) school commuting. Policies that curtail bus usage may reduce bus emissions but yield even larger increases in private-vehicle emissions. Our findings underscore the need to critically evaluate transportation-related environmental and health impacts of currently proposed changes in school policy.

  6. Differences in active commuting among younger and older adults.

    PubMed

    Bopp, Melissa; Der Ananian, Cheryl; Campbell, Matthew E

    2014-04-01

    The demonstrated health benefits of active commuting (AC) and low participation rates among older adults indicate a need to examine the socioecological correlates of AC by age category. An online survey of employed U.S. adults examined AC participation and individual, employment-related, community, and environmental variables. Participants were dichotomized by age (younger: 18-49 yr; n = 638, 64% and older: ≥ 50 yr; n = 359, 36%). Logistic-regression analyses examined differences in AC correlates by age. Older adults were less likely to be active commuters (13.4%) than younger adults (27.9%; p < .001) For older adults, analyses yielded a Nagelkerke R2 = .76, with perceived behavioral control, behavioral beliefs, household cars, and walking distance as predictors. Analyses for younger adults resulted in a Nagelkerke R2 = .79, with perceived behavioral control, coworker normative beliefs, parking problems at work, greater employer and community support for AC, and bad weather as predictors. Findings suggest age should be considered when examining and targeting AC behaviors.

  7. Examining the Link Between Public Transit Use and Active Commuting

    PubMed Central

    Bopp, Melissa; Gayah, Vikash V.; Campbell, Matthew E.

    2015-01-01

    Background: An established relationship exists between public transportation (PT) use and physical activity. However, there is limited literature that examines the link between PT use and active commuting (AC) behavior. This study examines this link to determine if PT users commute more by active modes. Methods: A volunteer, convenience sample of adults (n = 748) completed an online survey about AC/PT patterns, demographic, psychosocial, community and environmental factors. t-test compared differences between PT riders and non-PT riders. Binary logistic regression analyses examined the effect of multiple factors on AC and a full logistic regression model was conducted to examine AC. Results: Non-PT riders (n = 596) reported less AC than PT riders. There were several significant relationships with AC for demographic, interpersonal, worksite, community and environmental factors when considering PT use. The logistic multivariate analysis for included age, number of children and perceived distance to work as negative predictors and PT use, feelings of bad weather and lack of on-street bike lanes as a barrier to AC, perceived behavioral control and spouse AC were positive predictors. Conclusions: This study revealed the complex relationship between AC and PT use. Further research should investigate how AC and public transit use are related. PMID:25898405

  8. Differences in active commuting among younger and older adults.

    PubMed

    Bopp, Melissa; Der Ananian, Cheryl; Campbell, Matthew E

    2014-04-01

    The demonstrated health benefits of active commuting (AC) and low participation rates among older adults indicate a need to examine the socioecological correlates of AC by age category. An online survey of employed U.S. adults examined AC participation and individual, employment-related, community, and environmental variables. Participants were dichotomized by age (younger: 18-49 yr; n = 638, 64% and older: ≥ 50 yr; n = 359, 36%). Logistic-regression analyses examined differences in AC correlates by age. Older adults were less likely to be active commuters (13.4%) than younger adults (27.9%; p < .001) For older adults, analyses yielded a Nagelkerke R2 = .76, with perceived behavioral control, behavioral beliefs, household cars, and walking distance as predictors. Analyses for younger adults resulted in a Nagelkerke R2 = .79, with perceived behavioral control, coworker normative beliefs, parking problems at work, greater employer and community support for AC, and bad weather as predictors. Findings suggest age should be considered when examining and targeting AC behaviors. PMID:23689245

  9. Commuter exposure to aerosol pollution on public transport in Singapore

    NASA Astrophysics Data System (ADS)

    Tan, S.; Velasco, E.; Roth, M.; Norford, L.

    2013-12-01

    Personal exposure to aerosol pollutants in the transport microenvironment of Singapore has not been well documented. Studies from many cities suggest that brief periods of exposure to high concentrations of airborne pollutants may have significant health impacts. Thus, a large proportion of aerosol exposure may be experienced during daily commuting trips due to the proximity to traffic. A better understanding of the variability across transport modes is therefore needed to design transport policies that minimize commuters' exposure. In light of this, personal exposure measurements of PM10 and PM2.5, particle number (PN), black carbon (BC), carbon monoxide (CO), particle-bound polycyclic aromatic hydrocarbons (pPAH), and active surface area (SA) were conducted on a selected route in downtown Singapore. Portable and real-time monitoring instruments were carried onto three different modes of public transport (bus, taxi, subway) and by foot. Simultaneous measurements were taken at a nearby park to capture the background concentrations. Large variability was observed amongst the various transport modes investigated. For example, the particle number concentration was on average 1.5, 1.6, 0.8, and 2.2 times higher inside buses, taxis, subway and by foot, respectively, than at the background site. Based on the results, it is possible to come up with a ranking of the 'cleanest' transport mode for Singapore.

  10. Numerical simulation of nonlinear dynamical systems driven by commutative noise

    SciTech Connect

    Carbonell, F. Biscay, R.J.; Jimenez, J.C.; Cruz, H. de la

    2007-10-01

    The local linearization (LL) approach has become an effective technique for the numerical integration of ordinary, random and stochastic differential equations. One of the reasons for this success is that the LL method achieves a convenient trade-off between numerical stability and computational cost. Besides, the LL method reproduces well the dynamics of nonlinear equations for which other classical methods fail. However, in the stochastic case, most of the reported works has been focused in Stochastic Differential Equations (SDE) driven by additive noise. This limits the applicability of the LL method since there is a number of interesting dynamics observed in equations with multiplicative noise. On the other hand, recent results show that commutative noise SDEs can be transformed into a random differential equation (RDE) by means of a random diffeomorfism (conjugacy). This paper takes advantages of such conjugacy property and the LL approach for defining a LL scheme for SDEs driven by commutative noise. The performance of the proposed method is illustrated by means of numerical simulations.

  11. Effects of Automobile Commute Characteristics on Affect and Job Candidate Evaluations: A Field Experiment

    ERIC Educational Resources Information Center

    Van Rooy, David L.

    2006-01-01

    The current study assesses the effects of the commuting environment on affective states and hiring decisions. A total of 136 undergraduate females were randomly assigned to one of four conditions based on the length (10 km vs. 30 km) and level of congestion (low vs. high) during a commute. Multivariate analyses of variance indicate that affective…

  12. Non-commutative holomorphic functions in elements of a Lie algebra and the absolute basis problem

    NASA Astrophysics Data System (ADS)

    Dosi, Anar A.

    2009-12-01

    We study the absolute basis problem in algebras of holomorphic functions in non-commuting variables generating a finite-dimensional nilpotent Lie algebra \\mathfrak{g}. This is motivated by J. L. Taylor's programme of non-commutative holomorphic functional calculus in the Lie algebra framework.

  13. Real hypersurfaces in the complex quadric with commuting and parallel Ricci tensor

    NASA Astrophysics Data System (ADS)

    Suh, Young Jin

    2016-08-01

    First we introduce the notion of commuting and parallel Ricci tensor for real hypersurfaces in the complex quadric Qm = SOm+2 / SO2 SOm. Then, according to the A-isotropic unit normal N, we give a complete classification of real hypersurfaces in Qm = SOm+2 / SO2 SOm with commuting and parallel Ricci tensor.

  14. 49 CFR 37.51 - Key stations in commuter rail systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Key stations in commuter rail systems. 37.51 Section 37.51 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Transportation Facilities § 37.51 Key stations in commuter rail...

  15. Communicating with Commuters. Numerous Factors Must Be Considered To Improve Process.

    ERIC Educational Resources Information Center

    Rue, Penny

    1982-01-01

    Guidelines are given for producing a newsletter to provide information about campus programs, activities, and services of interest to commuting students. The following questions regarding newsletters are answered: (1) What information do commuting students need? (2) What format would be most effective? (3) How can news and articles be obtained?…

  16. Urban Corridor Consortium Task Force on Part-Time and Commuter Students. Final Report.

    ERIC Educational Resources Information Center

    Wisconsin Univ. Urban Corridor Consortium.

    Ways that urban corridor campuses might respond to the increasing enrollment of part-time and commuter students were reviewed by the University of Wisconsin Urban Corridor Consortium Task Force on Part-Time and Commuter Students. Members of the consortia are the following University of Wisconsin campuses: Green Bay, Milwaukee, Oshkosh, Parkside,…

  17. 77 FR 72432 - Application of Boutique Air, Inc. for Commuter Air Carrier Authority

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-05

    ... Office of the Secretary Application of Boutique Air, Inc. for Commuter Air Carrier Authority AGENCY... order finding Boutique Air, Inc., fit, willing, and able, and awarding it commuter air carrier authority... Attachment A to the order. FOR FURTHER INFORMATION CONTACT: Barbara Snoden, Air Carrier Fitness Division...

  18. [Socio-demographic and spatial structures within commuting range of Warsaw].

    PubMed

    Rakowski, W; Gocal, T

    1989-01-01

    Using official data for 1983, the authors describe the geographic and socioeconomic zones of influence that the city of Warsaw, Poland, exerts on surrounding areas. Special attention is paid to the effects of commuting for work to and from the city on regional labor markets. Some demographic characteristics of commuters are discussed. (SUMMARY IN ENG AND RUS)

  19. Road factors and bicycle-motor vehicle crashes at unsignalized priority intersections.

    PubMed

    Schepers, J P; Kroeze, P A; Sweers, W; Wüst, J C

    2011-05-01

    In this study, the safety of cyclists at unsignalized priority intersections within built-up areas is investigated. The study focuses on the link between the characteristics of priority intersection design and bicycle-motor vehicle (BMV) crashes. Across 540 intersections that are involved in the study, the police recorded 339 failure-to-yield crashes with cyclists in four years. These BMV crashes are classified into two types based on the movements of the involved motorists and cyclists: • type I: through bicycle related collisions where the cyclist has right of way (i.e. bicycle on the priority road); • type II: through motor vehicle related collisions where the motorist has right of way (i.e. motorist on the priority road). The probability of each crash type was related to its relative flows and to independent variables using negative binomial regression. The results show that more type I crashes occur at intersections with two-way bicycle tracks, well marked, and reddish coloured bicycle crossings. Type I crashes are negatively related to the presence of raised bicycle crossings (e.g. on a speed hump) and other speed reducing measures. The accident probability is also decreased at intersections where the cycle track approaches are deflected between 2 and 5m away from the main carriageway. No significant relationships are found between type II crashes and road factors such as the presence of a raised median.

  20. Bicycle helmet use and non-use – recently published research

    PubMed Central

    2012-01-01

    Bicycle traumata are very common and especially neurologic complications lead to disability and death in all stages of the life. This review assembles the most recent findings concerning research in the field of bicycle traumata combined with the factor of bicycle helmet use. The area of bicycle trauma research is by nature multidisciplinary and relevant not only for physicians but also for experts with educational, engineering, judicial, rehabilitative or public health functions. Due to this plurality of global publications and special subjects, short time reviews help to detect recent research directions and provide also information from neighbour disciplines for researchers. It can be stated that to date, that although a huge amount of research has been conducted in this area more studies are needed to evaluate and improve special conditions and needs in different regions, ages, nationalities and to create successful prevention programs of severe head and face injuries while cycling. Focus was explicit the bicycle helmet use, wherefore sledding, ski and snowboard studies were excluded and only one study concerning electric bicycles remained due to similar motion structures within this review. The considered studies were all published between January 2010 and August 2011 and were identified via the online databases Medline PubMed and ISI Web of Science. PMID:22632628

  1. Association of Sociodemographic and Perceived Environmental Factors with Public Bicycle Use among Taiwanese Urban Adults

    PubMed Central

    Liao, Yung

    2016-01-01

    Background: This study examined the sociodemographic and perceived environmental factors associated with public bicycle use among Taiwanese urban adults. Methods: A random-digit-dialing telephone-based cross-sectional survey was administered to Taiwanese urban adults aged 20–64 years in 2015. Data on sociodemographic variables, perceived environmental factors (for attributes identified in the International Physical Activity Questionnaire-Environmental Module), and public bicycle use were obtained from 1002 adults in three cities. Adjusted logistic regression was used. Results: After adjustment for potential confounders, the results showed that adults aged 20–29 years (odds ratio (OR) = 4.42) with a university degree or higher (OR = 2.03) were more likely to use public bicycles. In addition, adults living in Kaohsiung City were less likely to use public bicycles (OR = 0.24). Adults who saw people being active (OR = 1.76; 95% CI: 1.05–2.86) and had positive aesthetic experiences of their environment (OR = 1.69) were more likely to use public bicycles. Conclusions: Our findings suggest that seeing physically active people and positive aesthetic perceptions of the environment are key factors for developing transportation policies and intervention strategies for promoting public bicycle use among Taiwanese urban adults. PMID:27007385

  2. What do cyclists need to see to avoid single-bicycle crashes?

    PubMed

    Schepers, Paul; den Brinker, Berry

    2011-04-01

    The number of single-bicycle crash victims is substantial in countries with high levels of cycling. To study the role of visual characteristics of the infrastructure, such as pavement markings, in single-bicycle crashes, a study in two steps was conducted. In Study 1, a questionnaire study was conducted among bicycle crash victims (n = 734). Logistic regression was used to study the relationship between the crashes and age, light condition, alcohol use, gaze direction and familiarity with the crash scene. In Study 2, the image degrading and edge detection method (IDED-method) was used to investigate the visual characteristics of 21 of the crash scenes. The results of the studies indicate that crashes, in which the cyclist collided with a bollard or road narrowing or rode off the road, were related to the visual characteristics of bicycle facilities. Edge markings, especially in curves of bicycle tracks, and improved conspicuity of bollards are recommended. STATEMENT OF RELEVANCE: Elevated single-bicycle crash numbers are common in countries with high levels of cycling. No research has been conducted on what cyclists need to see to avoid this type of crash. The IDED-method to investigate crash scenes is new and proves to be a powerful tool to quantify 'visual accessibility'. PMID:21491274

  3. The bricycle: a bicycle in zero gravity can be balanced or steered but not both

    NASA Astrophysics Data System (ADS)

    Dong, O.; Graham, C.; Grewal, A.; Parrucci, C.; Ruina, A.

    2014-12-01

    A bicycle or inverted pendulum can be balanced, that is kept nearly upright, by accelerating the base. This balance is achieved by steering on a bicycle. Simultaneously one can also control the lateral position of the base: changing of the track line of a bike or the position of hand under a balanced stick. We show here with theory and experiment that if the balance problem is removed, by making the system neutrally stable for balance, one cannot simultaneously maintain balance and control the position of the base. We made a bricycle, essentially a bicycle with springy training wheels. The stiffness of the training wheel suspension can be varied from near infinite, making the bricycle into a tricycle, to zero, making it effectively a bicycle. The springy training wheels effectively reduce or even negate gravity, at least for balance purposes. One might expect a smooth transition from tricycle to bicycle as the stiffness is varied, in terms of handling, balance and feel. Not so. At an intermediate stiffness, when gravity is effectively zeroed, riders can balance easily but no longer turn. Small turns cause an intolerable leaning. Thus there is a qualitative difference between bicycles and tricycles, a difference that cannot be met halfway.

  4. Active commuting and physical activity in adolescents from Europe: results from the HELENA study.

    PubMed

    Chillón, Palma; Ortega, Francisco B; Ruiz, Jonatan R; De Bourdeaudhuij, Ilse; Martínez-Gómez, David; Vicente-Rodriguez, Germán; Widhalm, Kurt; Molnar, Dénes; Gottrand, Frédéric; González-Gross, Marcela; Ward, Dianne S; Moreno, Luis A; Castillo, Manuel J; Sjöström, Michael

    2011-05-01

    We assessed commuting patterns in adolescents from 10 European cities and examined associations with physical activity (PA). A total of 3112 adolescents were included. PA was objectively measured with accelerometry. Commuting patterns and overall PA were self-reported using questions from the International Physical Activity Questionnaire modified for adolescents (IPAQ-A). Adolescents reported to spend 30 min (15,60) [expressed as median (25th, 75th percentiles)] walking. In boys, associations between active commuting (walking and biking) and PA levels were observed for moderate, moderate-to-vigorous and overall PA. In girls, these associations were observed for moderate and moderate-to-vigorous PA (walking). Similar results were found with the IPAQ-A. We observed positive associations between overall commuting and PA levels in European adolescents, yet due to the cross-sectional study design we cannot state the direction of these. Future studies should address the causation between active commuting and PA levels.

  5. Methods and apparatus using commutative error detection values for fault isolation in multiple node computers

    DOEpatents

    Almasi, Gheorghe [Ardsley, NY; Blumrich, Matthias Augustin [Ridgefield, CT; Chen, Dong [Croton-On-Hudson, NY; Coteus, Paul [Yorktown, NY; Gara, Alan [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Hoenicke, Dirk I [Ossining, NY; Singh, Sarabjeet [Mississauga, CA; Steinmacher-Burow, Burkhard D [Wernau, DE; Takken, Todd [Brewster, NY; Vranas, Pavlos [Bedford Hills, NY

    2008-06-03

    Methods and apparatus perform fault isolation in multiple node computing systems using commutative error detection values for--example, checksums--to identify and to isolate faulty nodes. When information associated with a reproducible portion of a computer program is injected into a network by a node, a commutative error detection value is calculated. At intervals, node fault detection apparatus associated with the multiple node computer system retrieve commutative error detection values associated with the node and stores them in memory. When the computer program is executed again by the multiple node computer system, new commutative error detection values are created and stored in memory. The node fault detection apparatus identifies faulty nodes by comparing commutative error detection values associated with reproducible portions of the application program generated by a particular node from different runs of the application program. Differences in values indicate a possible faulty node.

  6. Exploring Universal Patterns in Human Home-Work Commuting from Mobile Phone Data

    PubMed Central

    Kung, Kevin S.; Greco, Kael; Sobolevsky, Stanislav; Ratti, Carlo

    2014-01-01

    Home-work commuting has always attracted significant research attention because of its impact on human mobility. One of the key assumptions in this domain of study is the universal uniformity of commute times. However, a true comparison of commute patterns has often been hindered by the intrinsic differences in data collection methods, which make observation from different countries potentially biased and unreliable. In the present work, we approach this problem through the use of mobile phone call detail records (CDRs), which offers a consistent method for investigating mobility patterns in wholly different parts of the world. We apply our analysis to a broad range of datasets, at both the country (Portugal, Ivory Coast, and Saudi Arabia), and city (Boston) scale. Additionally, we compare these results with those obtained from vehicle GPS traces in Milan. While different regions have some unique commute time characteristics, we show that the home-work time distributions and average values within a single region are indeed largely independent of commute distance or country (Portugal, Ivory Coast, and Boston)–despite substantial spatial and infrastructural differences. Furthermore, our comparative analysis demonstrates that such distance-independence holds true only if we consider multimodal commute behaviors–as consistent with previous studies. In car-only (Milan GPS traces) and car-heavy (Saudi Arabia) commute datasets, we see that commute time is indeed influenced by commute distance. Finally, we put forth a testable hypothesis and suggest ways for future work to make more accurate and generalizable statements about human commute behaviors. PMID:24933264

  7. Towards a differentiated understanding of active travel behaviour: Using social theory to explore everyday commuting

    PubMed Central

    Guell, C.; Panter, J.; Jones, N.R.; Ogilvie, D.

    2012-01-01

    Fostering physical activity is an established public health priority for the primary prevention of a variety of chronic diseases. One promising population approach is to seek to embed physical activity in everyday lives by promoting walking and cycling to and from work (‘active commuting’) as an alternative to driving. Predominantly quantitative epidemiological studies have investigated travel behaviours, their determinants and how they may be changed towards more active choices. This study aimed to depart from narrow behavioural approaches to travel and investigate the social context of commuting with qualitative social research methods. Within a social practice theory framework, we explored how people describe their commuting experiences and make commuting decisions, and how travel behaviour is embedded in and shaped by commuters' complex social worlds. Forty-nine semi-structured interviews and eighteen photo-elicitation interviews with accompanying field notes were conducted with a subset of the Commuting and Health in Cambridge study cohort, based in the UK. The findings are discussed in terms of three particularly pertinent facets of the commuting experience. Firstly, choice and decisions are shaped by the constantly changing and fluid nature of commuters' social worlds. Secondly, participants express ambiguities in relation to their reasoning, ambitions and identities as commuters. Finally, commuting needs to be understood as an embodied and emotional practice. With this in mind, we suggest that everyday decision-making in commuting requires the tactical negotiation of these complexities. This study can help to explain the limitations of more quantitative and static models and frameworks in predicting travel behaviour and identify future research directions. PMID:22486840

  8. Communication Networks and Perceptions of Social Support as Antecedents to College Adjustment: A Comparison between Student Commuters and Campus Residents.

    ERIC Educational Resources Information Center

    Somera, Lilnabeth P.; Ellis, Beth Hartman

    1996-01-01

    Presents a two-part study that looks at the impact of social support on college adjustment among "traditional" campus residents and commuters. Begins with a review of social support measures and the relationship between commuting and college adjustment. Finds factors critical to academic adjustment vary in the contexts of commuting students and…

  9. Incidence and costs of bicycle-related traumatic brain injuries in the Netherlands.

    PubMed

    Scholten, Annemieke C; Polinder, Suzanne; Panneman, Martien J M; van Beeck, Ed F; Haagsma, Juanita A

    2015-08-01

    The main cause of death and serious disability in bicycle accidents is traumatic brain injury (TBI). The aim of this population-based study was to assess the incidence and costs of bicycle-related TBI across various age groups, and in comparison to all bicycle-related injuries, to identify main risk groups for the development of preventive strategies. Data from the National Injury Surveillance System and National Medical Registration were used for all patients with bicycle-related injuries and TBI who visited a Dutch emergency department (ED) between 1998 and 2012. Demographics and national, weighted estimates of injury mechanism, injury severity and costs were analysed per age group. Direct healthcare costs and indirect costs were determined using the incidence-based Dutch Burden of Injury Model. Between 1998 and 2012, the incidence of ED treatments due to bicycle-related TBI strongly increased with 54%, to 43 per 100,000 persons in 2012. However, the incidence of all bicycle-related injuries remained stable, from 444 in 1998 to 456/100,000 in 2012. Incidence of hospital admission increased in both TBI (92%) and all injuries from cycling (71%). Highest increase in incidence of both ED treatments and hospital admissions was seen in adults aged 55+. The injury rate of TBI per kilometre travelled increased (44%) except in children, but decreased (-4%) for all injuries, showing a strong decrease in children (-36%) but an increase in men aged 25+, and women aged 15+. Total costs of bicycle-related TBI were €74.5 million annually. Although bicycle-related TBI accounted for 9% of the incidence of all ED treatments due to cycling, it accounted for 18% of the total costs due to all bicycle-related injuries (€410.7 million). Children and adolescents (aged 0-24) had highest incidence of ED treatments due to bicycle-related injuries. Men in the working population (aged 15-64) had highest indirect costs following injuries from cycling, including TBI. Older cyclists (aged

  10. Incidence and costs of bicycle-related traumatic brain injuries in the Netherlands.

    PubMed

    Scholten, Annemieke C; Polinder, Suzanne; Panneman, Martien J M; van Beeck, Ed F; Haagsma, Juanita A

    2015-08-01

    The main cause of death and serious disability in bicycle accidents is traumatic brain injury (TBI). The aim of this population-based study was to assess the incidence and costs of bicycle-related TBI across various age groups, and in comparison to all bicycle-related injuries, to identify main risk groups for the development of preventive strategies. Data from the National Injury Surveillance System and National Medical Registration were used for all patients with bicycle-related injuries and TBI who visited a Dutch emergency department (ED) between 1998 and 2012. Demographics and national, weighted estimates of injury mechanism, injury severity and costs were analysed per age group. Direct healthcare costs and indirect costs were determined using the incidence-based Dutch Burden of Injury Model. Between 1998 and 2012, the incidence of ED treatments due to bicycle-related TBI strongly increased with 54%, to 43 per 100,000 persons in 2012. However, the incidence of all bicycle-related injuries remained stable, from 444 in 1998 to 456/100,000 in 2012. Incidence of hospital admission increased in both TBI (92%) and all injuries from cycling (71%). Highest increase in incidence of both ED treatments and hospital admissions was seen in adults aged 55+. The injury rate of TBI per kilometre travelled increased (44%) except in children, but decreased (-4%) for all injuries, showing a strong decrease in children (-36%) but an increase in men aged 25+, and women aged 15+. Total costs of bicycle-related TBI were €74.5 million annually. Although bicycle-related TBI accounted for 9% of the incidence of all ED treatments due to cycling, it accounted for 18% of the total costs due to all bicycle-related injuries (€410.7 million). Children and adolescents (aged 0-24) had highest incidence of ED treatments due to bicycle-related injuries. Men in the working population (aged 15-64) had highest indirect costs following injuries from cycling, including TBI. Older cyclists (aged

  11. The Effects of Surface-Induced Loads on Forearm Muscle Activity During Steering a Bicycle

    PubMed Central

    Arpinar-Avsar, Pinar; Birlik, Gülin; Sezgin, Önder C.; Soylu, Abdullah R.

    2013-01-01

    On the bicycle, the human upper extremity has two essential functions in steering the bicycle and in supporting the body. Through the handlebar, surface- induced loads are transmitted to the hand and arm of the bicycle rider under vibration exposure conditions. Thus, the purpose of the study was to investigate the effect of vibration exposure on forearm muscle activity for different road surfaces (i.e. smooth road, concrete stone pavement, rough road) and for different bicycles. Ten subjects participated in experiments and two types of bicycles, i.e. Road Bike (RB) and Mountain Bike (MTB) are compared. The acceleration magnitudes were dominant along x and z-axes. The r.m.s acceleration values in the z direction at the stem of MTB were at most 2.56, 7.04 and 10.76 m·s-2 when pedaling respectively on asphalt road, concrete pavement and rough road. In the case of RB the corresponding values were respectively 4.43, 11.75 and 27.31 m·s-2. The cumulative normalized muscular activity levels during MTB trials on different surfaces had the same tendency as with acceleration amplitudes and have ranked in the same order from lowest to highest value. Although road bike measurements have resulted in a similar trend of increment, the values computed for rough road trials were higher than those in MTB trials. During rough road measurements on MTB, rmsEMG of extensor muscles reached a value corresponding to approximately 50% of MVC (Maximum Voluntary Contraction). During RB trials performed on rough road conditions, rmsEMG (%MVC) values for the forearm flexor muscles reached 45.8% of their maximal. The level of muscular activity of forearm muscles in controlling handlebar movements has been observed to be enhanced by the increase in the level of vibration exposed on the bicycle. Since repeated forceful gripping and pushing forces to a handle of a vibratory tool can create a risk of developing circulatory, neurological, or musculoskeletal disorder, a bicycle rider can be

  12. Optimization of electric bicycle for youths with disabilities.

    PubMed

    Blumenstein, Tobias; Zeitlmann, Hilar; Alves-Pinto, Ana; Turova, Varvara; Lampe, Renée

    2014-01-01

    Cerebral palsy is a group of neurodevelopmental disorders that affect a person's ability to move and to maintain balance and posture. People with cerebral palsy have also perception and space orientation deficits so that special assistance devices should be developed to compensate these handicaps. The objective was to optimize an adapted electric bicycle (E-bike) for youths with neurodevelopmental disorders. An adapted E-bike was provided with ultrasonic sensors that measure distances to objects. If the distance to other objects reduces, an acoustic signal is sent. Additionally, a self-created force plate was fixed on the pedal to evaluate the muscle performances during biking. An experiment with the ultrasound warning system confirmed that acoustic feedback was helpful in avoiding obstacles. The measurement of the blood pressure, the heart frequency and the pedaling force during biking approved that the training condition of the test person can be registered and enables tuning the power of the electric motor to individual requirements. The results demonstrate that an adapted E-bike can be improved to provide better space orientation for people with perceptual disorders and to measure training conditions of patients. Moreover, these enable individual adjustment of the electric motor power to optimize comfort and therapy effect.

  13. How does the edge height of curb ramps obstruct bicycles?

    PubMed

    Hayashi, Masahiro; Uetake, Teruo; Shimoda, Masahiro

    2012-12-01

    The aim of this study is to recommend revisions, based on empirical data, to the current curb ramp standards for keeping bicyclists safe. Four types of curb ramps were tested: (1) concrete with a 50 mm edge height, (2) concrete reinforced by a metal plate with a 50 mm edge height, (3) plastic with a 20 mm edge height, and (4) recycled rubber with a 10 mm edge height. Twenty subjects aged 20-60 years ascended the curbs on a bicycle under various conditions. The angles of approach were 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees and 90 degrees. Experiments were executed under both wet and dry conditions. We found that when approaching from an angle of 45 degrees or more, all subjects could ascend all ramps under both conditions. From a 15 degrees approach under wet conditions, no subjects ascended the concrete ramps. Some could not ascend at a 15 degrees approach on the concrete ramps in dry conditions, and some could not ascend from a 30 degrees approach on the reinforced concrete ramp in wet conditions. Bicyclists riding on roadways cannot easily ascend a curb ramp with a 50 mm edge, even in dry conditions. We thus recommend that curb ramp edge heights be lower than 50 mm. Keywords: friction coefficient; approach angle PMID:25665200

  14. A regioselective double Stille coupling reaction of bicyclic stannolanes.

    PubMed

    Kamimura, Akio; Tanaka, Toshiyuki; So, Masahiro; Itaya, Tomoyuki; Matsuda, Kantaro; Kawamoto, Takuji

    2016-09-14

    A regioselective double Stille coupling reaction was explored using bicyclic stannolanes that were easily prepared from the radical cascade reaction of β-amino-α-methylene esters. Various 1-bromo-2-iodoarenes underwent the double coupling reaction to afford benzoisoindole derivatives in a regioselective manner, where the carbon attached to the iodine selectively coupled with the vinylic carbon, and then the carbon attached to bromine coupled with the alkyl carbon. The combination of intra- and intermolecular coupling reactions provided hexahydroindeno[1,2-b]pyrrole derivatives in good yields. The yields were further improved in the presence of excess amounts of CsF. An attempt to identify the reaction intermediate was made wherein the decomposition of the stannolanes with aqueous HCl and HBr afforded trigonal bipyramidal (TBP) pentacoordinated tin complexes, as confirmed by microanalyses and (119)Sn NMR. Using DCl for the decomposition selectively introduced a deuterium to the E-position of the exomethylene unit. The complexes smoothly underwent the intramolecular Stille coupling reaction in the presence of both a palladium catalyst and DABCO, affording hexahydroindeno[1,2-b]pyrroles in good yields. These results suggest that the double coupling reaction progresses through a TBP tin complex, promoting the second intramolecular coupling reaction between the aryl halide and Csp(3)-tin bond. PMID:27506959

  15. A regioselective double Stille coupling reaction of bicyclic stannolanes.

    PubMed

    Kamimura, Akio; Tanaka, Toshiyuki; So, Masahiro; Itaya, Tomoyuki; Matsuda, Kantaro; Kawamoto, Takuji

    2016-09-14

    A regioselective double Stille coupling reaction was explored using bicyclic stannolanes that were easily prepared from the radical cascade reaction of β-amino-α-methylene esters. Various 1-bromo-2-iodoarenes underwent the double coupling reaction to afford benzoisoindole derivatives in a regioselective manner, where the carbon attached to the iodine selectively coupled with the vinylic carbon, and then the carbon attached to bromine coupled with the alkyl carbon. The combination of intra- and intermolecular coupling reactions provided hexahydroindeno[1,2-b]pyrrole derivatives in good yields. The yields were further improved in the presence of excess amounts of CsF. An attempt to identify the reaction intermediate was made wherein the decomposition of the stannolanes with aqueous HCl and HBr afforded trigonal bipyramidal (TBP) pentacoordinated tin complexes, as confirmed by microanalyses and (119)Sn NMR. Using DCl for the decomposition selectively introduced a deuterium to the E-position of the exomethylene unit. The complexes smoothly underwent the intramolecular Stille coupling reaction in the presence of both a palladium catalyst and DABCO, affording hexahydroindeno[1,2-b]pyrroles in good yields. These results suggest that the double coupling reaction progresses through a TBP tin complex, promoting the second intramolecular coupling reaction between the aryl halide and Csp(3)-tin bond.

  16. Bicycle accident-related head injuries in India

    PubMed Central

    Munivenkatappa, Ashok; Devi, Bhagavatula Indira; Gregor, Thomas Issac; Bhat, Dhananjay I.; Kumarsamy, Akhil Deepika; Shukla, Dhaval P.

    2013-01-01

    Objectives: To describe the epidemiology of head injuries sustained due to bicycle accidents in India. Materials and Methods: Data were retrospectively collected over a period of six months (15 May 2011 to 15 November 2011). Demography of patients, Glasgow coma scale (GCS), clinical and imaging findings, and mortality and outcome using Glasgow outcome scale (GOS), Rivermead post-concussion symptom questionnaire (RPCSQ) and Rivermead head injury follow-up questionnaire (RHFUQ), were analyzed. Outcome was assessed by telephonic interview. Results: There were 108 patients (100 males) with mean age of 27.7 years. Seventy-four (68.5%) were from rural areas. Accidents due to vehicular collision accounted for 60 (55.6%) cases. None wore a helmet. The admission GCS was 14-15 in 68.5% cases, 13-3 in 31.5%. The risk of moderate to severe injuries was increased among working laborers (OR = 5), and patients with loss of consciousness (OR = 4). Sixty-three (49%) patients had abnormal computed tomography (CT) findings; most common finding was skull fracture 25 (23.1%). Four patients needed surgery. The GOS assessment at three to six months revealed favorable outcome in 66 patients (61.1%) and death in 8 (7.4%). The common post-concussion symptoms were headache, fatigue, and poor concentration. Conclusion: The majority of hospitalized cyclists were from a rural background and of the lower income group. After three months the majority of patients had good recovery with few persistent concussion symptoms. PMID:24250156

  17. The Aeroflex: A Bicycle for Mobile Air Quality Measurements

    PubMed Central

    Elen, Bart; Peters, Jan; Van Poppel, Martine; Bleux, Nico; Theunis, Jan; Reggente, Matteo; Standaert, Arnout

    2013-01-01

    Fixed air quality stations have limitations when used to assess people's real life exposure to air pollutants. Their spatial coverage is too limited to capture the spatial variability in, e.g., an urban or industrial environment. Complementary mobile air quality measurements can be used as an additional tool to fill this void. In this publication we present the Aeroflex, a bicycle for mobile air quality monitoring. The Aeroflex is equipped with compact air quality measurement devices to monitor ultrafine particle number counts, particulate mass and black carbon concentrations at a high resolution (up to 1 second). Each measurement is automatically linked to its geographical location and time of acquisition using GPS and Internet time. Furthermore, the Aeroflex is equipped with automated data transmission, data pre-processing and data visualization. The Aeroflex is designed with adaptability, reliability and user friendliness in mind. Over the past years, the Aeroflex has been successfully used for high resolution air quality mapping, exposure assessment and hot spot identification. PMID:23262484

  18. Heparin-induced circular dichroism of an achiral, bicyclic species.

    PubMed

    Stanley, Floyd E; Warner, Andrew M; McWilliams, Kayla M; Stalcup, Apryll M

    2011-01-01

    Antimalarial drugs have shown potential in suppressing the role of glycosaminoglycans (GAGs) in the pathology of prion protein conformational disorders (e.g. "Mad Cow" disease) by competing for sites of electrostatic interaction. In this study, circular dichroism (CD) and UV/Visible (UV/Vis) absorption spectroscopy techniques were used to investigate the interactions between N-methyl-N'-(7-chloro-4-quinolyl)-1,3-diaminopropane (QD), an achiral, bicyclic compound similar to previously investigated antimalarial drugs, and heparin, a complex GAG that is frequently used as a clinical anticoagulant. Relatively intense heparin-induced CD features were observed for QD and were noted to be radically different from previous studies using related chiral drugs, underscoring the importance of the Pfieffer effect on this and similar heparin research. Additionally, the induced CD for QD was observed to be highly dependent upon drug concentration, heparin concentration, system pH, equilibration time, and ionic strength. These results, in connection with recent work, provide new insight into the nature of the association between GAGs and antimalarial species. PMID:21125690

  19. The Aeroflex: a bicycle for mobile air quality measurements.

    PubMed

    Elen, Bart; Peters, Jan; Poppel, Martine Van; Bleux, Nico; Theunis, Jan; Reggente, Matteo; Standaert, Arnout

    2013-01-01

    Fixed air quality stations have limitations when used to assess people's real life exposure to air pollutants. Their spatial coverage is too limited to capture the spatial variability in, e.g., an urban or industrial environment. Complementary mobile air quality measurements can be used as an additional tool to fill this void. In this publication we present the Aeroflex, a bicycle for mobile air quality monitoring. The Aeroflex is equipped with compact air quality measurement devices to monitor ultrafine particle number counts, particulate mass and black carbon concentrations at a high resolution (up to 1 second). Each measurement is automatically linked to its geographical location and time of acquisition using GPS and Internet time. Furthermore, the Aeroflex is equipped with automated data transmission, data pre-processing and data visualization. The Aeroflex is designed with adaptability, reliability and user friendliness in mind. Over the past years, the Aeroflex has been successfully used for high resolution air quality mapping, exposure assessment and hot spot identification. 

  20. [Acute effects of eccentric work on a bicycle ergometer].

    PubMed

    Netreba, A I; Popov, D V; Tsvirkun, D V; Vinogradova, O L

    2008-01-01

    The dynamics of delayed onset of muscle soreness after exercise on an electrically driven cycle ergometer with floating seat under preferentially concentric and eccentric conditions (forward and backward rotation of the pedals) has been evaluated using three different tests. The delayed onset of muscle soreness was determined using three different procedures: two with active contraction of the tested muscle group in multi-joint (going downstairs) and single-joint (knee extension) movements and one with passive pressure applied to the central part of m. vastus lateralis. With the use of two active tests, the maximum delayed onset of muscle soreness was recorded on the 1st-3rd days after intensive bicycle exercise without significant differences between the groups. Under conditions of passive testing, a tendency to a slower development (both an increase and a decrease) of delayed onset of muscle soreness was recorded. A positive correlation between the relative tension and the delayed onset of muscle soreness was found. Relative tension was determined as a decrease of strength during recovery related to the initial level. No relationship between volume/duration of exercise and the delayed onset of muscle soreness was found.

  1. Big Bicycle Data Processing: from Personal Data to Urban Applications

    NASA Astrophysics Data System (ADS)

    Pettit, C. J.; Lieske, S. N.; Leao, S. Z.

    2016-06-01

    Understanding the flows of people moving through the built environment is a vital source of information for the planners and policy makers who shape our cities. Smart phone applications enable people to trace themselves through the city and these data can potentially be then aggregated and visualised to show hot spots and trajectories of macro urban movement. In this paper our aim is to develop procedures for cleaning, aggregating and visualising human movement data and translating this into policy relevant information. In conducting this research we explore using bicycle data collected from a smart phone application known as RiderLog. We focus on the RiderLog application initially in the context of Sydney, Australia and discuss the procedures and challenges in processing and cleaning this data before any analysis can be made. We then present some preliminary map results using the CartoDB online mapping platform where data are aggregated and visualised to show hot spots and trajectories of macro urban movement. We conclude the paper by highlighting some of the key challenges in working with such data and outline some next steps in processing the data and conducting higher volume and more extensive analysis.

  2. Environmental Determinants of Bicycling Injuries in Alberta, Canada

    PubMed Central

    Romanow, Nicole T. R.; Couperthwaite, Amy B.; McCormack, Gavin R.; Nettel-Aguirre, Alberto; Rowe, Brian H.; Hagel, Brent E.

    2012-01-01

    This study examined environmental risk factors for bicycling injuries, by combining data on bicyclist injuries collected by interviews in the emergency department (ED) with street-level environmental audits of injury locations, capturing path, roadway, safety, land use, and aesthetic characteristics. Cases were bicyclists struck by a motor vehicle (MV) or with severe injuries (hospitalized). Controls were bicyclists who were not hit by a car or those seen and discharged from the ED, matched on time and day of injury. Logistic regression odds ratios (ORs) adjusted for age, sex, peak time, and bicyclist speed with 95% confidence intervals (CIs) were estimated to relate injury risk to environmental characteristics. Factors contributing to MV events included greater traffic volume (OR 5.13; 95% CI [1.44, 18.27]), intersections (OR 6.89; 95% CI [1.48, 32.14]), retail establishments (OR 5.56; 95% CI [1.72, 17.98]), and path obstructions (OR 3.83; 95% CI [1.03, 14.25]). Locations where the road was in good condition (OR 0.25; 95% CI [0.07, 0.96]) and where there was high surveillance from surrounding buildings (OR 0.32; 95% CI [0.13, 0.82]) were associated with less severe injuries. These findings could be used by bicyclists and transportation planners to improve safety. PMID:23251192

  3. Optimization of electric bicycle for youths with disabilities.

    PubMed

    Blumenstein, Tobias; Zeitlmann, Hilar; Alves-Pinto, Ana; Turova, Varvara; Lampe, Renée

    2014-01-01

    Cerebral palsy is a group of neurodevelopmental disorders that affect a person's ability to move and to maintain balance and posture. People with cerebral palsy have also perception and space orientation deficits so that special assistance devices should be developed to compensate these handicaps. The objective was to optimize an adapted electric bicycle (E-bike) for youths with neurodevelopmental disorders. An adapted E-bike was provided with ultrasonic sensors that measure distances to objects. If the distance to other objects reduces, an acoustic signal is sent. Additionally, a self-created force plate was fixed on the pedal to evaluate the muscle performances during biking. An experiment with the ultrasound warning system confirmed that acoustic feedback was helpful in avoiding obstacles. The measurement of the blood pressure, the heart frequency and the pedaling force during biking approved that the training condition of the test person can be registered and enables tuning the power of the electric motor to individual requirements. The results demonstrate that an adapted E-bike can be improved to provide better space orientation for people with perceptual disorders and to measure training conditions of patients. Moreover, these enable individual adjustment of the electric motor power to optimize comfort and therapy effect. PMID:25485189

  4. Mixed-state fidelity susceptibility through iterated commutator series expansion

    NASA Astrophysics Data System (ADS)

    Tonchev, N. S.

    2014-11-01

    We present a perturbative approach to the problem of computation of mixed-state fidelity susceptibility (MFS) for thermal states. The mathematical techniques used provide an analytical expression for the MFS as a formal expansion in terms of the thermodynamic mean values of successively higher commutators of the Hamiltonian with the operator involved through the control parameter. That expression is naturally divided into two parts: the usual isothermal susceptibility and a constituent in the form of an infinite series of thermodynamic mean values which encodes the noncommutativity in the problem. If the symmetry properties of the Hamiltonian are given in terms of the generators of some (finite-dimensional) algebra, the obtained expansion may be evaluated in a closed form. This issue is tested on several popular models, for which it is shown that the calculations are much simpler if they are based on the properties from the representation theory of the Heisenberg or SU(1, 1) Lie algebra.

  5. Mixed-state fidelity susceptibility through iterated commutator series expansion.

    PubMed

    Tonchev, N S

    2014-11-01

    We present a perturbative approach to the problem of computation of mixed-state fidelity susceptibility (MFS) for thermal states. The mathematical techniques used provide an analytical expression for the MFS as a formal expansion in terms of the thermodynamic mean values of successively higher commutators of the Hamiltonian with the operator involved through the control parameter. That expression is naturally divided into two parts: the usual isothermal susceptibility and a constituent in the form of an infinite series of thermodynamic mean values which encodes the noncommutativity in the problem. If the symmetry properties of the Hamiltonian are given in terms of the generators of some (finite-dimensional) algebra, the obtained expansion may be evaluated in a closed form. This issue is tested on several popular models, for which it is shown that the calculations are much simpler if they are based on the properties from the representation theory of the Heisenberg or SU(1, 1) Lie algebra. PMID:25493736

  6. Complexity and non-commutativity of learning operations on graphs.

    PubMed

    Atmanspacher, Harald; Filk, Thomas

    2006-07-01

    We present results from numerical studies of supervised learning operations in small recurrent networks considered as graphs, leading from a given set of input conditions to predetermined outputs. Graphs that have optimized their output for particular inputs with respect to predetermined outputs are asymptotically stable and can be characterized by attractors, which form a representation space for an associative multiplicative structure of input operations. As the mapping from a series of inputs onto a series of such attractors generally depends on the sequence of inputs, this structure is generally non-commutative. Moreover, the size of the set of attractors, indicating the complexity of learning, is found to behave non-monotonically as learning proceeds. A tentative relation between this complexity and the notion of pragmatic information is indicated.

  7. Sleep Deprivation Is Associated with Bicycle Accidents and Slip and Fall Injuries in Korean Adolescents

    PubMed Central

    Kim, So Young; Sim, Songyong; Kim, Sung-Gyun; Choi, Hyo Geun

    2015-01-01

    Objective This study sought to evaluate associations between sleep time and bicycle accidents, falls under various circumstances, and dental injuries in adolescents. Methods A total of 61,696 participants ranging from 12 to 18 years of age who completed the Korea Youth Risk Behavior Web-based Survey (KYRBWS) in 2013 were enrolled in this study. Bicycle riding accidents were analyzed for 17,232 bicycle-riding participants. Data were collected regarding the weekday sleep duration for the most recent 7 days, which was categorized as < 5.5 h, 5.5–6.5 h, 6.5–7.5 h, or ≥ 7.5 h per day, and the incidence of bicycle accidents, slips and falls under various circumstances, and dental injuries in the most recent 12 months. Adjusted odds ratios (aORs) were calculated among sleep groups for bicycle accidents, slips and falls, and dental injuries using simple and multiple logistic regression analyses with complex sampling. Results Bicycle riding accidents and slips and falls in classrooms, corridors, the ground, toilets, stairs, and other unspecified situations showed positive correlations with sleep deprivation. Comparisons of groups with ≥ 7.5 h sleep, < 5.5 h, 5.5–6.5 h sleep, and 6.5–7.5 h sleep revealed increased associations with slips and falls under various circumstances. In particular, the aORs were higher in the groups with less sleep (aOR of the 5.5 h group > the 5.5–6.5 h group > the 6.5–7.5 h group). There was no significant relationship between sleep deprivation and dental injury. Conclusions This study demonstrated that sleep deprivation among Korean adolescents was associated with bicycle accidents and falls at home and school. Thus, adequate sleep may be needed to prevent accidents and falls. PMID:26280345

  8. Reducing drag of a commuter train, using engine exhaust momentum

    NASA Astrophysics Data System (ADS)

    Ha, Dong Keun

    The objective of this thesis was to perform numerical investigations of two different methods of injecting fluid momentum into the air flow above a commuter train to reduce its drag. Based on previous aerodynamic modifications of heavy duty trucks in improving fuel efficiency, two structural modifications were designed and applied to a Metrolink Services commuter train in the Los Angeles (LA) County area to reduce its drag and subsequently improve fuel efficiency. The first modification was an L-shaped channel, added to the exhaust cooling fan above the locomotive roof to divert and align the exhaust gases in the axial direction. The second modification was adding an airfoil shaped lid over the L-shape channel, to minimize the drag of the perturbed structure, and thus reduce the overall drag. The computational fluid dynamic (CFD) software CCM+ from CD-Adapco with the ?-? turbulence model was used for the simulations. A single train set which consists of three vehicles: one locomotive, one trailer car and one cab car were used. All the vehicles were modeled based on the standard Metrolink fleet train size. The wind speed was at 90 miles per hour (mph), which is the maximum speed for the Orange County Metrolink line. Air was used as the exhaust gas in the simulation. The temperature of the exhausting air emitting out of the cooling fan on the roof was 150 F and the average fan speed was 120 mph. Results showed that with the addition of the lid, momentum injection results in reduced flow separation and pressure recovery behind the locomotive, which reduces the overall drag by at least 30%.

  9. Commuter motorcycle crashes in Malaysia: An understanding of contributing factors

    PubMed Central

    Oxley, Jennifer; Yuen, Jeremy; Ravi, Mano Deepa; Hoareau, Effie; Mohammed, Mohammed Azman Aziz; Bakar, Harun; Venkataraman, Saraswathy; Nair, Prame Kumar

    2013-01-01

    In Malaysia, two-thirds of reported workplace-related fatal and serious injury incidents are the result of commuting crashes (especially those involving motorcyclists), however, little is known about the contributing factors to these collisions. A telephone survey of 1,750 motorcyclists (1,004 adults who had been involved in a motorcycle commuting crash in the last 2 years and 746 adult motorcyclists who had not been involved in a motorcycle crash in the last 2 years) was undertaken. The contributions of a range of behavioural, attitudinal, employment and travel pattern factors to collision involvement were examined. The findings revealed that the majority of participants were licensed riders, rode substantial distances (most often for work purposes), and reported adopting safe riding practices (helmet wearing and buckling). However, there were some concerning findings regarding speeding behaviour, use of mobile phones while riding, and engaging in other risky behaviours. Participants who had been involved in a collision were younger (aged 25–29 years), had higher exposure (measured by distances travelled, frequency of riding, and riding on high volume and higher speed roads), reported higher rates of riding for work purposes, worked more shift hours and had a higher likelihood of riding at relatively high speeds compared with participants who had not been involved in a collision. Collisions generally occurred during morning and early evening hours, striking another vehicles, and during normal traffic flow. The implications of these findings for policy decisions and development of evidence-based behavioural/training interventions addressing key contributing factors are discussed. PMID:24406945

  10. Commutative law for products of infinitely large isotropic random matrices

    NASA Astrophysics Data System (ADS)

    Burda, Zdzislaw; Livan, Giacomo; Swiech, Artur

    2013-08-01

    Ensembles of isotropic random matrices are defined by the invariance of the probability measure under the left (and right) multiplication by an arbitrary unitary matrix. We show that the multiplication of large isotropic random matrices is spectrally commutative and self-averaging in the limit of infinite matrix size N→∞. The notion of spectral commutativity means that the eigenvalue density of a product ABC... of such matrices is independent of the order of matrix multiplication, for example, the matrix ABCD has the same eigenvalue density as ADCB. In turn, the notion of self-averaging means that the product of n independent but identically distributed random matrices, which we symbolically denote by AAA..., has the same eigenvalue density as the corresponding power An of a single matrix drawn from the underlying matrix ensemble. For example, the eigenvalue density of ABCCABC is the same as that of A2B2C3. We also discuss the singular behavior of the eigenvalue and singular value densities of isotropic matrices and their products for small eigenvalues λ→0. We show that the singularities at the origin of the eigenvalue density and of the singular value density are in one-to-one correspondence in the limit N→∞: The eigenvalue density of an isotropic random matrix has a power-law singularity at the origin ˜|λ|-s with a power s∈(0,2) when and only when the density of its singular values has a power-law singularity ˜λ-σ with a power σ=s/(4-s). These results are obtained analytically in the limit N→∞. We supplement these results with numerical simulations for large but finite N and discuss finite-size effects for the most common ensembles of isotropic random matrices.

  11. Quantum groups, non-commutative differential geometry and applications

    SciTech Connect

    Schupp, P

    1993-12-09

    The topic of this thesis is the development of a versatile and geometrically motivated differential calculus on non-commutative or quantum spaces, providing powerful but easy-to-use mathematical tools for applications in physics and related sciences. A generalization of unitary time evolution is proposed and studied for a simple 2-level system, leading to non-conservation of microscopic entropy, a phenomenon new to quantum mechanics. A Cartan calculus that combines functions, forms, Lie derivatives and inner derivations along general vector fields into one big algebra is constructed for quantum groups and then extended to quantum planes. The construction of a tangent bundle on a quantum group manifold and an BRST type approach to quantum group gauge theory are given as further examples of applications. The material is organized in two parts: Part I studies vector fields on quantum groups, emphasizing Hopf algebraic structures, but also introducing a ``quantum geometric`` construction. Using a generalized semi-direct product construction we combine the dual Hopf algebras A of functions and U of left-invariant vector fields into one fully bicovariant algebra of differential operators. The pure braid group is introduced as the commutant of {Delta}(U). It provides invariant maps A {yields} U and thereby bicovariant vector fields, casimirs and metrics. This construction allows the translation of undeformed matrix expressions into their less obvious quantum algebraic counter parts. We study this in detail for quasitriangular Hopf algebras, giving the determinant and orthogonality relation for the ``reflection`` matrix. Part II considers the additional structures of differential forms and finitely generated quantum Lie algebras -- it is devoted to the construction of the Cartan calculus, based on an undeformed Cartan identity.

  12. Spontaneous Usage of Different Shortcuts Based on the Commutativity Principle

    PubMed Central

    Gaschler, Robert; Vaterrodt, Bianca; Frensch, Peter A.; Eichler, Alexandra; Haider, Hilde

    2013-01-01

    Based on research on expertise a person can be said to possess integrated conceptual knowledge when she/he is able to spontaneously identify task relevant information in order to solve a problem efficiently. Despite the lack of instruction or explicit cueing, the person should be able to recognize which shortcut strategy can be applied – even when the task context differs from the one in which procedural knowledge about the shortcut was originally acquired. For mental arithmetic, first signs of such adaptive flexibility should develop already in primary school. The current study introduces a paper-and-pencil-based as well as an eyetracking-based approach to unobtrusively measure how students spot and apply (known) shortcut options in mental arithmetic. We investigated the development and the relation of the spontaneous use of two strategies derived from the mathematical concept of commutativity. Children from grade 2 to grade 7 and university students solved three-addends addition problems, which are rarely used in class. Some problems allowed the use of either of two commutativity-based shortcut strategies. Results suggest that from grade three onwards both of the shortcuts were used spontaneously and application of one shortcut correlated positively with application of the other. Rate of spontaneous usage was substantial but smaller than in an instructed variant. Eyetracking data suggested similar fixation patterns for spontaneous an instructed shortcut application. The data are consistent with the development of an integrated concept of the mathematical principle so that it can be spontaneously applied in different contexts and strategies. PMID:24086413

  13. Coulomb problem in non-commutative quantum mechanics

    SciTech Connect

    Galikova, Veronika; Presnajder, Peter

    2013-05-15

    The aim of this paper is to find out how it would be possible for space non-commutativity (NC) to alter the quantum mechanics (QM) solution of the Coulomb problem. The NC parameter {lambda} is to be regarded as a measure of the non-commutativity - setting {lambda}= 0 which means a return to the standard quantum mechanics. As the very first step a rotationally invariant NC space R{sub {lambda}}{sup 3}, an analog of the Coulomb problem configuration space (R{sup 3} with the origin excluded) is introduced. R{sub {lambda}}{sup 3} is generated by NC coordinates realized as operators acting in an auxiliary (Fock) space F. The properly weighted Hilbert-Schmidt operators in F form H{sub {lambda}}, a NC analog of the Hilbert space of the wave functions. We will refer to them as 'wave functions' also in the NC case. The definition of a NC analog of the hamiltonian as a hermitian operator in H{sub {lambda}} is one of the key parts of this paper. The resulting problem is exactly solvable. The full solution is provided, including formulas for the bound states for E < 0 and low-energy scattering for E > 0 (both containing NC corrections analytic in {lambda}) and also formulas for high-energy scattering and unexpected bound states at ultra-high energy (both containing NC corrections singular in {lambda}). All the NC contributions to the known QM solutions either vanish or disappear in the limit {lambda}{yields} 0.

  14. Photography of the commutation spark using a high-speed camera

    NASA Astrophysics Data System (ADS)

    Hanazawa, Tamio; Egashira, Torao; Tanaka, Yasuhiro; Egoshi, Jun

    1997-12-01

    In the single-phase AC commutator motor (known as a universal motor), which is widely used in cleaners, electrical machines, etc., some problems generated by commutation sparks are wear on the brush and noise impediments. We have therefore attempted to use a high-speed camera to elucidate the commutation spark mechanism visually. The high-speed camera that we used is capable of photographing at 5,000 - 20,000,000 frames/s. Selection of a trigger module can be obtained from the operation unit and the exterior triggering signal. In this paper, we proposed an exterior trigger method that involved opening a hole of several millimeters across in the motor and using argon laser light, so that commutator segments may be photographed in position; we then conducted the experiment. This method enabled us to photograph the motor's commutator segment from any position, and we were able to confirm spark generation at every other commutator segment. Furthermore, after confirming the spark generation position of the commutator segment, we next attempted to accelerate the photographing speed to obtain more detailed photography of the moment of spark generation; we then prepared our report.

  15. The association between access to public transportation and self-reported active commuting.

    PubMed

    Djurhuus, Sune; Hansen, Henning S; Aadahl, Mette; Glümer, Charlotte

    2014-12-05

    Active commuting provides routine-based regular physical activity which can reduce the risk of chronic diseases. Using public transportation involves some walking or cycling to a transit stop, transfers and a walk to the end location and users of public transportation have been found to accumulate more moderate physical activity than non-users. Understanding how public transportation characteristics are associated with active transportation is thus important from a public health perspective. This study examines the associations between objective measures of access to public transportation and self-reported active commuting. Self-reported time spent either walking or cycling commuting each day and the distance to workplace were obtained for adults aged 16 to 65 in the Danish National Health Survey 2010 (n = 28,928). Access to public transportation measures were computed by combining GIS-based road network distances from home address to public transit stops an integrating their service level. Multilevel logistic regression was used to examine the association between access to public transportation measures and active commuting. Distance to bus stop, density of bus stops, and number of transport modes were all positively associated with being an active commuter and with meeting recommendations of physical activity. No significant association was found between bus services at the nearest stop and active commuting. The results highlight the importance of including detailed measurements of access to public transit in order to identify the characteristics that facilitate the use of public transportation and active commuting.

  16. Commutability of the First World Health Organization International Standard for Human Cytomegalovirus

    PubMed Central

    Preiksaitis, J.; Tong, Y.; Pang, X.; Sun, Y.; Tang, L.; Cook, L.; Pounds, S.; Fryer, J.; Caliendo, A. M.

    2015-01-01

    Quantitative detection of cytomegalovirus (CMV) DNA has become a standard part of care for many groups of immunocompromised patients; recent development of the first WHO international standard for human CMV DNA has raised hopes of reducing interlaboratory variability of results. Commutability of reference material has been shown to be necessary if such material is to reduce variability among laboratories. Here we evaluated the commutability of the WHO standard using 10 different real-time quantitative CMV PCR assays run by eight different laboratories. Test panels, including aliquots of 50 patient samples (40 positive samples and 10 negative samples) and lyophilized CMV standard, were run, with each testing center using its own quantitative calibrators, reagents, and nucleic acid extraction methods. Commutability was assessed both on a pairwise basis and over the entire group of assays, using linear regression and correspondence analyses. Commutability of the WHO material differed among the tests that were evaluated, and these differences appeared to vary depending on the method of statistical analysis used and the cohort of assays included in the analysis. Depending on the methodology used, the WHO material showed poor or absent commutability with up to 50% of assays. Determination of commutability may require a multifaceted approach; the lack of commutability seen when using the WHO standard with several of the assays here suggests that further work is needed to bring us toward true consensus. PMID:26269622

  17. Active Commuting Behaviors in a Nordic Metropolitan Setting in Relation to Modality, Gender, and Health Recommendations

    PubMed Central

    Stigell, Erik; Schantz, Peter

    2015-01-01

    Active commuting between home and place of work or study is often cited as an interesting source of physical activity in a public health perspective. However, knowledge about these behaviors is meager. This was therefore studied in adult active commuters (n = 1872) in Greater Stockholm, Sweden, a Nordic metropolitan setting. They received questionnaires and individually adjusted maps to draw their normal commuting route. Three different modality groups were identified in men and women: single-mode cyclists and pedestrians (those who only cycle or walk, respectively) and dual-mode commuters (those who alternately walk or cycle). Some gender differences were observed in trip distances, frequencies, and velocities. A large majority of the commuting trip durations met the minimum health recommendation of at least 10-minute-long activity bouts. The median single-mode pedestrians and dual-mode commuters met or were close to the recommended weekly physical activity levels of at least 150 minutes most of the year, whereas the single-mode cyclists did so only during spring–mid-fall. A high total number of trips per year (range of medians: 231–389) adds to the value in a health perspective. To fully grasp active commuting behaviors in future studies, both walking and cycling should be assessed over different seasons and ideally over the whole year. PMID:26690193

  18. NYPA/TH!NK Clean Commute Program Final Report - Inception through December 2004

    SciTech Connect

    James Francfort; Don Karner

    2005-11-01

    The Clean Commute Program uses TH!NK city electric vehicles from Ford Motor Company’s electric vehicle group, TH!NK Mobility, to demonstrate the feasibility of using electric transportation in urban applications. Suburban New York City railroad commuters use the TH!NK city vehicles to commute from their private residences to railroad stations, where they catch commuter trains into New York City. Electric vehicle charging infrastructure for the TH!NK city vehicles is located at the commuters’ private residences as well as seven train stations. Ford leased at total of 97 TH!NK city electric vehicles to commuters from Westchester, Putnam, Rockland, Queens, Nassau, and Suffolk counties for $199 per month. First Clean Commute Program vehicle deliveries occurred late in 2001, with data collection commencing in February 2002. Through May, 2004, 24 of the lessees have returned their vehicles to Ford and no longer participate in the Clean Commute Program. Reasons given for leaving the Program include relocation out of the Program area, change in employment status, change in commuting status, and, in a few cases, dissatisfaction with the vehicle. Additionally, 13 vehicles were returned to Ford when the lease was completed. In August 2002, Ford announced that it was ceasing production of the TH!NK city and would not extend any TH!NK city leases. Mileage accumulation dropped in the last quarter of the program as vehicle leases were returned to Ford. The impact of the program overall was significant as participants in the Clean Commute Program drove their vehicles over 406,074 miles, avoiding the use of over 18,887 gallons of gasoline. During the active portion of the program, the TH!NK city vehicles were driven an average of between 180 and 230 miles per month. Over 95% of all trips taken with the TH!NK city vehicles replaced trips previously taken in gasoline vehicles. This report covers the period from Program inception through December 2004.

  19. NYPA/TH!NK Clean Commute Program Report – Inception Through May 2004

    SciTech Connect

    Don Karner; James Francfort; Randall Solomon

    2004-11-01

    The Clean Commute Program uses TH!NK city electric vehicles from Ford Motor Company’s electric vehicle group, TH!NK Mobility, to demonstrate the feasibility of using electric vehicles for transportation in urban applications. Suburban New York City railroad commuters use the TH!NK city vehicles to commute from their private residences to railroad stations, where they catch commuter trains into New York City. Electric vehicle charging infrastructure for the TH!NK city vehicles is located at the commuters’ private residences as well as seven train stations. Ford leased 97 TH!NK city electric vehicles to commuters from Westchester, Putnam, Rockland, Queens, Nassau, and Suffolk counties for $199 per month per vehicle. The first Clean Commute Program vehicle deliveries occurred late in 2001, with data collection commencing in February 2002. Through May 2004, 24 of the lessees have returned their vehicles to Ford and no longer participate in the Clean Commute Program. Reasons given for returning the vehicles include relocation out of the Program area, change in employment status, change in commuting status, and, in a few cases, dissatisfaction with the vehicle. Additionally, 13 vehicles have been returned to Ford as their leases have completed. In August 2002, Ford announced that it was ceasing production of the TH!NK city and would not extend any TH!NK city leases. Through May 2004, participants in the Clean Commute Program have driven their vehicles over 370,000 miles, avoiding the use of over 17,000 gallons of gasoline. The TH!NK city vehicles are driven an average of between 180 and 230 miles per month, and over 95% of all trips taken with the TH!NK city vehicles replace trips previously taken in gasoline vehicles. This report covers the period from Program inception through May 2004.

  20. Modular mechatronic system for stationary bicycles interfaced with virtual environment for rehabilitation

    PubMed Central

    2014-01-01

    Background Cycling has been used in the rehabilitation of individuals with both chronic and post-surgical conditions. Among the challenges with implementing bicycling for rehabilitation is the recruitment of both extremities, in particular when one is weaker or less coordinated. Feedback embedded in virtual reality (VR) augmented cycling may serve to address the requirement for efficacious cycling; specifically recruitment of both extremities and exercising at a high intensity. Methods In this paper a mechatronic rehabilitation bicycling system with an interactive virtual environment, called Virtual Reality Augmented Cycling Kit (VRACK), is presented. Novel hardware components embedded with sensors were implemented on a stationary exercise bicycle to monitor physiological and biomechanical parameters of participants while immersing them in an augmented reality simulation providing the user with visual, auditory and haptic feedback. This modular and adaptable system attaches to commercially-available stationary bicycle systems and interfaces with a personal computer for simulation and data acquisition processes. The complete bicycle system includes: a) handle bars based on hydraulic pressure sensors; b) pedals that monitor pedal kinematics with an inertial measurement unit (IMU) and forces on the pedals while providing vibratory feedback; c) off the shelf electronics to monitor heart rate and d) customized software for rehabilitation. Bench testing for the handle and pedal systems is presented for calibration of the sensors detecting force and angle. Results The modular mechatronic kit for exercise bicycles was tested in bench testing and human tests. Bench tests performed on the sensorized handle bars and the instrumented pedals validated the measurement accuracy of these components. Rider tests with the VRACK system focused on the pedal system and successfully monitored kinetic and kinematic parameters of the rider’s lower extremities. Conclusions The VRACK

  1. Design of a digital ride quality augmentation system for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Hammond, T. A.; Amin, S. P.; Paduano, J. D.; Downing, D. R.

    1984-01-01

    Commuter aircraft typically have low wing loadings, and fly at low altitudes, and so they are susceptible to undesirable accelerations caused by random atmospheric turbulence. Larger commercial aircraft typically have higher wing loadings and fly at altitudes where the turbulence level is lower, and so they provide smoother rides. This project was initiated based on the goal of making the ride of the commuter aircraft as smooth as the ride experienced on the major commercial airliners. The objectives of this project were to design a digital, longitudinal mode ride quality augmentation system (RQAS) for a commuter aircraft, and to investigate the effect of selected parameters on those designs.

  2. Sensor design for outdoor racing bicycle field testing for human vibration comfort evaluation

    NASA Astrophysics Data System (ADS)

    Vanwalleghem, Joachim; De Baere, Ives; Loccufier, Mia; Van Paepegem, Wim

    2013-09-01

    This paper is concerned with the vibrational comfort evaluation of the cyclist when cycling a rough surface. Outdoor comfort tests have so far only been done through instrumenting the bicycle with accelerometers. This work instruments a racing bicycle with custom-made contact force sensors and velocity sensors to acquire human comfort through the absorbed power method. Comfort evaluation is assessed at the hand-arm and seat interface of the cyclist with the bicycle. By means of careful finite-element analysis for designing the force gauges at the handlebar and the seat combined with precise calibration of both force and velocity sensors, all sensors have proven to work properly. Initial field tests are focused on the proper functioning of the designed sensors and their suitability for vibration comfort measurements. Tests on a cobblestone road reveal that the outcome of the absorbed power values is within the same range as those from laboratory tests found in the literature. This sensor design approach for outdoor testing with racing bicycles may give a new interpretation on evaluating the cyclist's comfort since the vibrational load is not only quantified in terms of acceleration but also in terms of force and velocity at the bicycle-cyclist contact points.

  3. Bicycle helmet use by children. Evaluation of a community-wide helmet campaign.

    PubMed

    DiGuiseppi, C G; Rivara, F P; Koepsell, T D; Polissar, L

    1989-10-27

    To assess the effect of a community-wide bicycle helmet campaign on helmet use, we observed 9827 children riding bicycles at sites in high-, middle-, and low-income census tracts in Seattle, Wash (intervention city), and Portland, Ore (control city); observations were made during 2-week intervals before and 4, 12, and 16 months after the campaign's start. Helmet use increased from 5.5% before the campaign to 15.7% afterward in Seattle and from 1.0% to 2.9% in Portland. Strong associations were found between helmet use and white compared with black or other race; riding geared vs nongeared bicycles; riding at playgrounds, in parks, or on bicycle paths vs on city streets; and riding with adults or other children compared with riding alone. The proportions of helmet wearers, adjusted for these variables, increased from 4.6% to 14.0% in Seattle and from 1.0% to 3.6% in Portland, a significantly greater increase in use in Seattle compared with Portland. We conclude that a community-wide bicycle helmet campaign can increase helmet use among children.

  4. Reversal of the bicycle drawing direction in Parkinson's disease by AC pulsed electromagnetic fields.

    PubMed

    Sandyk, R

    1998-09-01

    The Draw-a-Bicycle Test is employed in neuropsychological testing of cognitive skills since the bicycle design is widely known and also because of its complex structure. The Draw-a-Bicycle Test has been administered routinely to patients with Parkinson's disease (PD) and other neurodegenerative disorders to evaluate the effect of transcranial applications of AC pulsed electromagnetic fields (EMFs) in the picotesla flux density on visuoconstructional skills. A seminal observation is reported in 5 medicated PD patients who demonstrated reversal of spontaneous drawing direction of the bicycle after they received a series of transcranial treatments with AC pulsed EMFs. In 3 patients reversal of the bicycle drawing direction was observed shortly after the administration of pulsed EMFs while in 2 patients these changes were observed within a time lag ranging from several weeks to months. All patients also demonstrated a dramatic clinical response to the administration of EMFs. These findings are intriguing because changes in drawing direction do not occur spontaneously in normal individuals as a result of relateralization of cognitive functions. This report suggests that administration of AC pulsed EMFs may induce in some PD patients changes in hemispheric dominance during processing of a visuoconstructional task and that these changes may be predictive of a particularly favourable response to AC pulsed EMFs therapy.

  5. Factors associated with bicycle helmet use among young adolescents in a multinational sample

    PubMed Central

    Klein, K; Thompson, D; Scheidt, P; Overpeck, M; Gross, L; the, H

    2005-01-01

    Objective: To determine factors associated with variation in bicycle helmet use by youth of different industrialized countries. Design: A multinational cross sectional nationally representative survey of health behaviors including symptoms, risk taking, school setting, and family context. Setting: School based survey of 26 countries. Subjects: School students, ages 11, 13, and 15 years totaling 112 843. Outcome measures: Reported frequency of bicycle helmet use among bicycle riders. Results: Reported helmet use varied greatly by country from 39.2% to 1.9%, with 12 countries reporting less than 10% of the bicycle riders as frequent helmet users and 14 countries more than 10%. Reported helmet use was highest at 11 years and decreased as children's age increased. Use was positively associated with other healthy behaviors, with parental involvement, and with per capita gross domestic product of the country. It is negatively associated with risk taking behaviors. Countries reported to have interventions promoting helmet use, exemplified by helmet giveaway programmes, had greater frequency of reported helmet use than those without programmes. Conclusions: Bicycle helmet use among young adolescents varies greatly between countries; however, helmet use does not reach 50% in any country. Age is the most significant individual factor associated with helmet for helmet using countries. The observation that some helmet promotion programmes are reported for countries with relatively higher student helmet use and no programmes reported for the lowest helmet use countries, suggests the possibility of a relation and the need for objective evaluation of programme effectiveness. PMID:16203837

  6. Identifying factors of bicycle comfort: An online survey with enthusiast cyclists.

    PubMed

    Ayachi, F S; Dorey, J; Guastavino, C

    2015-01-01

    Racing bicycles have evolved significantly over the past decades as technology and cyclists' comfort have become a critical design issue. Although ample research has been conducted on comfort for other means of transportation, cyclists' perception of dynamic comfort has received scant attention in the scientific literature. The present study investigates how enthusiast cyclists conceptualize comfort using an online survey with 244 respondents. The purpose is to determine which factors contribute to comfort when riding a bicycle, to identify situations in which comfort is relevant and to determine the extent to which vibrations play a role in comfort evaluations. We found that comfort is influenced by factors related to bicycle components (specifically the frame, saddle and handlebar), as well as environmental factors (type or road, weather conditions) and factors related to the cyclist (position, adjustments, body parts). Respondents indicated that comfort is a concern when riding a bicycle in most situations and they believed that comfort is compatible with performance. The PCA analysis shows that for the perception "human factor-body parts" are put in evidence, and the "cyclist's comfort" evaluation is mainly based on certain qualities related to the bicycle components, then the road and external conditions (e.g. weather, temperature).

  7. The impact response of traditional and BMX-style bicycle helmets at different impact severities.

    PubMed

    DeMarco, Alyssa L; Chimich, Dennis D; Gardiner, John C; Siegmund, Gunter P

    2016-07-01

    Bicycle helmets reduce the frequency and severity of severe to fatal head and brain injuries in bicycle crashes. Our goal here was to measure the impact attenuation performance of common bicycle helmets over a range of impact speeds. We performed 127 drop tests using 13 different bicycle helmet models (6 traditional style helmets and 7 BMX-style helmets) at impact speeds ranging from 1 to 10m/s onto a flat anvil. Helmets were struck on their left front and/or right front areas, a common impact location that was at or just below the test line of most bicycle helmet standards. All but one of the 10 certified helmet models remained below the 300g level at an impact speed of 6m/s, whereas none of the 3 uncertified helmets met this criterion. We found that the helmets with expanded polystyrene liners performed similarly and universally well. The single certified helmet with a polyurethane liner performed below the level expected by the Consumer Product Safety Commission (CPSC) standard at our impact location and the helmet structure failed during one of two supplemental tests of this helmet above the test line. Overall, we found that increased liner thickness generally reduced peak headform acceleration, particularly at higher impact speeds.

  8. Specificity of leg power changes to velocities used in bicycle endurance training.

    PubMed

    Rösler, K; Conley, K E; Howald, H; Gerber, C; Hoppeler, H

    1986-07-01

    Increases in leg power production resulting from 8 wk of bicycle endurance training (30 min/day, 5 times/wk) were studied using an isokinetic dynamometer. In addition, biopsies of vastus lateralis were analyzed to characterize muscle ultrastructural changes. Performance increased on the dynamometer specifically near the estimated average knee angular velocity used during the bicycle training (200 degrees/s). Power measurements were made during the first 5 contractions (maximal power: Pmax) and last 5 contractions (final power: Pend) of 25 and 50 consecutive contractions (at 60 and 240 degrees/s, respectively). Pmax and Pend increased only at 240 degrees/s but not at 60 degrees/s. These increases in Pmax (86 W) and Pend (78 W) resulted primarily from longer torque maintenance but also from increased peak torque during each contraction and were close to the increase in mechanical power output maintained on the bicycle (Pb; 78 W) during the training sessions. The specificity of these changes to the angular velocities used in the bicycle training indicates a neural basis to these adaptations. We suggest that these neural adaptations, coupled with the observed enhancement of muscle mitochondrial and capillary density (+41 and +15%, respectively) underlie the increased ability to maintain power production on a bicycle after endurance training.

  9. The role of conspicuity in preventing bicycle crashes involving a motor vehicle

    PubMed Central

    Woodward, Alistair; Ameratunga, Shanthi

    2015-01-01

    Background: Bicycle use, despite its proven health and other benefits, is rarely part of everyday travel for many people due to the perceived risk of injury from collision crashes. This article investigated the role of physical vs. attention conspicuity in preventing bicycle crashes involving a motor vehicle in New Zealand. Methods: The Taupo Bicycle Study involved 2590 adult cyclists recruited in 2006 (43.1% response rate) and followed for bicycle crash outcomes through linkage to four national databases. A composite measure of physical conspicuity was created using latent class analysis based on the use of fluorescent colours, lights and reflective materials, and the main colour of top, helmet and bike frame. Attention conspicuity was assessed based on regional differences in travel patterns and the amount of riding in a bunch. Cox regression modelling for repeated events was performed with multivariate adjustments. Results: During a median follow-up period of 6.4 years, 162 participants experienced 187 bicycle–motor vehicle crashes. The crash risk was not predicted by the four latent classes identified and the amount of bunch riding but was higher in Auckland, the region with the lowest level of bicycle use relative to car use. In subgroup analyses, compared to other latent classes, the most physically conspicuous group had a higher risk in Auckland but a lower risk in other regions. Conclusion: Conspicuity aids may not be effective in preventing bicycle–motor vehicle crashes in New Zealand, particularly in Auckland, where attention conspicuity is low. PMID:25085469

  10. Comment on ‘On the stability of a bicycle on rollers’

    NASA Astrophysics Data System (ADS)

    Dressel, Andrew; Papadopoulos, Jim M.

    2012-07-01

    In their paper ‘On the stability of a bicycle on rollers’, Patricia A Cleary and Pirooz Mohazzabi (2012 Eur. J. Phys. 32 1293) incorrectly assert that two key differences exist between riding a bicycle on pavement and riding on rollers. The first is that riding a bicycle on rollers somehow tests the role of the centrifugal force and the second is that a lack of inertia or forward momentum on rollers somehow decreases stability. The most straightforward explanation for why these differences do not exist is Galilean invariance. Although it is true that the steer and yaw angles, and thus the magnitude of any lateral acceleration, are limited because of the narrow width of a treadmill or rollers, which certainly can make balancing more difficult, the accelerations that do occur are identical to those which would be found by riding within a similarly narrow path of fixed pavement. In fact, even though a bicycle on rollers or a treadmill has no forward momentum in a frame of reference that is stationary with respect to the ground, it has the same balance dynamics, and thus stability, as the same bicycle on fixed pavement.

  11. Evaluating the Safety Effects of Bicycle Lanes in New York City

    PubMed Central

    Srinivasan, Raghavan; McKnight, Claire E.; Ewing, Reid; Roe, Matthew

    2012-01-01

    Objectives. We evaluated the effects of on-street bicycle lanes installed prior to 2007 on different categories of crashes (total crashes, bicyclist crashes, pedestrian crashes, multiple-vehicle crashes, and injurious or fatal crashes) occurring on roadway segments and at intersections in New York City. Methods. We used generalized estimating equation methodology to compare changes in police-reported crashes in a treatment group and a comparison group before and after installation of bicycle lanes. Our study approach allowed us to control confounding factors, such as built environment characteristics, that cannot typically be controlled when a comparison group is used. Results. Installation of bicycle lanes did not lead to an increase in crashes, despite the probable increase in the number of bicyclists. The most likely explanations for the lack of increase in crashes are reduced vehicular speeds and fewer conflicts between vehicles and bicyclists after installation of these lanes. Conclusions. Our results indicate that characteristics of the built environment have a direct impact on crashes and that they should thus be controlled in studies evaluating traffic countermeasures such as bicycle lanes. To prevent crashes at intersections, we recommend installation of “bike boxes” and markings that indicate the path of bicycle lanes across intersections. PMID:22095351

  12. Latent segmentation based count models: Analysis of bicycle safety in Montreal and Toronto.

    PubMed

    Yasmin, Shamsunnahar; Eluru, Naveen

    2016-10-01

    The study contributes to literature on bicycle safety by building on the traditional count regression models to investigate factors affecting bicycle crashes at the Traffic Analysis Zone (TAZ) level. TAZ is a traffic related geographic entity which is most frequently used as spatial unit for macroscopic crash risk analysis. In conventional count models, the impact of exogenous factors is restricted to be the same across the entire region. However, it is possible that the influence of exogenous factors might vary across different TAZs. To accommodate for the potential variation in the impact of exogenous factors we formulate latent segmentation based count models. Specifically, we formulate and estimate latent segmentation based Poisson (LP) and latent segmentation based Negative Binomial (LNB) models to study bicycle crash counts. In our latent segmentation approach, we allow for more than two segments and also consider a large set of variables in segmentation and segment specific models. The formulated models are estimated using bicycle-motor vehicle crash data from the Island of Montreal and City of Toronto for the years 2006 through 2010. The TAZ level variables considered in our analysis include accessibility measures, exposure measures, sociodemographic characteristics, socioeconomic characteristics, road network characteristics and built environment. A policy analysis is also conducted to illustrate the applicability of the proposed model for planning purposes. This macro-level research would assist decision makers, transportation officials and community planners to make informed decisions to proactively improve bicycle safety - a prerequisite to promoting a culture of active transportation. PMID:27442595

  13. Longitudinal associations between neighborhood-level street network with walking, bicycling, and jogging: The CARDIA study

    PubMed Central

    Hou, Ningqi; Popkin, Barry M; Jacobs, David R; Song, Yan; Guilkey, David; Lewis, Cora E.; Gordon-Larsen, Penny

    2010-01-01

    Objective To investigate the differential association between neighborhood-level street network with walking, bicycling, and jogging by urbanicity and gender. Methods We used prospective data from 4 repeated exams on 5,115 young adults recruited in 1985–86, followed through 2000–01, with self-reported walking, bicycling, and jogging. Using a Geographic Information System, we spatially and temporally linked time-varying residential locations to street network data within a 1 Euclidean km buffer. Two-part marginal effect modeling assessed longitudinal associations between neighborhood-level street network with walking, bicycling, and jogging, by urbanicity and gender, controlling for time-varying individual- and census-level covariates. Results Neighborhood street density was positively associated with walking, bicycling, and jogging in low urbanicity areas, but in middle and high urbanicity areas, these associations became null (men) or inverse (women). Conclusion Characteristics of neighborhood streets may influence adult residents’ walking, bicycling, and jogging, particularly in less urban areas. This research may inform policy efforts to encourage physical activity. PMID:20801072

  14. The impact response of traditional and BMX-style bicycle helmets at different impact severities.

    PubMed

    DeMarco, Alyssa L; Chimich, Dennis D; Gardiner, John C; Siegmund, Gunter P

    2016-07-01

    Bicycle helmets reduce the frequency and severity of severe to fatal head and brain injuries in bicycle crashes. Our goal here was to measure the impact attenuation performance of common bicycle helmets over a range of impact speeds. We performed 127 drop tests using 13 different bicycle helmet models (6 traditional style helmets and 7 BMX-style helmets) at impact speeds ranging from 1 to 10m/s onto a flat anvil. Helmets were struck on their left front and/or right front areas, a common impact location that was at or just below the test line of most bicycle helmet standards. All but one of the 10 certified helmet models remained below the 300g level at an impact speed of 6m/s, whereas none of the 3 uncertified helmets met this criterion. We found that the helmets with expanded polystyrene liners performed similarly and universally well. The single certified helmet with a polyurethane liner performed below the level expected by the Consumer Product Safety Commission (CPSC) standard at our impact location and the helmet structure failed during one of two supplemental tests of this helmet above the test line. Overall, we found that increased liner thickness generally reduced peak headform acceleration, particularly at higher impact speeds. PMID:27077273

  15. Effectiveness of Bicycle Safety Helmets in Preventing Facial Injuries in Road Accidents

    PubMed Central

    Stier, Rebecca; Otte, Dietmar; Müller, Christian; Petri, Maximilian; Gaulke, Ralph; Krettek, Christian; Brand, Stephan

    2016-01-01

    Background The effectiveness of bicycle safety helmets in preventing head injuries is well- documented. Recent studies differ regarding the effectiveness of bicycle helmets in preventing facial injuries, especially those of the mid-face and the mandible. Objectives The present study was conducted to determine the protective effect of a bicycle helmet in preventing mid-face and mandibular fractures. Patients and Methods Data from an accident research unit were analyzed to collect technical collision details (relative collision speed, type of collision, collision partner, and use of a helmet) and clinical data (type of fracture). Results Between 1999 and 2011, 5,350 bicycle crashes were included in the study. Of these, 175 (3.3%) had fractures of the mid-face or mandible. In total, 228 mid-face or mandibular fractures were identified. A significant correlation was found between age and relative collision speed, and the incidence of a fracture. While no significant correlation was found between the use of a helmet and the incidence of mid-facial fractures, the use of a helmet was correlated with a significantly increased incidence of mandibular fractures. Conclusions Higher age of cyclists and increasing speed of the accident opponent significantly increase the likelihood of sustaining facial fractures. The use of bicycle helmets does not significantly reduce the incidence of mid-facial fractures, while being correlated with an even increased incidence of mandibular fractures. PMID:27800459

  16. Movement and skill analysis of supercross bicycle motocross.

    PubMed

    Cowell, John F; McGuigan, Michael R; Cronin, John B

    2012-06-01

    The purpose of this study was to develop a greater understanding of Supercross bicycle motocross (BMX) via notational analysis. Union Cycliste Internationale (UCI) categorized Elite riders (n = 26) were the subjects of the analysis; this event occurred during the UCI BMX World Championships. Video footage was captured and analyzed using Quicktime™ and VideoMotion© software. The movement patterns and time spent pedaling, jumping, and "pumping" were determined for each run. On average, the Elite Men took 39.62 ± 0.78 seconds to complete a track, using 30.45 ± 3.2 pedal strokes and spent 11.83 ± 1.11, 9.64 ± 1.79, and 17.05 ± 1.51 seconds pedaling, jumping, and "pumping," respectively. The Elite Women took 40.95 ± 0.91 seconds to complete a track, using 33.65 ± 5.06 pedal strokes and spent 14.40 ± 2.17, 6.28 ± 1.41, and 17.80 ± 1.83 seconds pedaling, jumping, and "coasting and pumping," respectively. The dominant movement patterns investigated for the start, takeoff, landing, and pumping were hip (∼30 times per lap) and knee extension (~30 per leg per lap) and horizontal shoulder abduction and adduction (20 times per lap). Future research is needed to identify the power and acceleration profiles of the sport, which would be paramount for determining the best practice in testing and preparing BMX athletes. Exercises that specifically target the extensors of the hips, knees, and ankles and the muscles responsible for horizontal shoulder abduction and adduction are recommended. PMID:21921819

  17. Movement and skill analysis of supercross bicycle motocross.

    PubMed

    Cowell, John F; McGuigan, Michael R; Cronin, John B

    2012-06-01

    The purpose of this study was to develop a greater understanding of Supercross bicycle motocross (BMX) via notational analysis. Union Cycliste Internationale (UCI) categorized Elite riders (n = 26) were the subjects of the analysis; this event occurred during the UCI BMX World Championships. Video footage was captured and analyzed using Quicktime™ and VideoMotion© software. The movement patterns and time spent pedaling, jumping, and "pumping" were determined for each run. On average, the Elite Men took 39.62 ± 0.78 seconds to complete a track, using 30.45 ± 3.2 pedal strokes and spent 11.83 ± 1.11, 9.64 ± 1.79, and 17.05 ± 1.51 seconds pedaling, jumping, and "pumping," respectively. The Elite Women took 40.95 ± 0.91 seconds to complete a track, using 33.65 ± 5.06 pedal strokes and spent 14.40 ± 2.17, 6.28 ± 1.41, and 17.80 ± 1.83 seconds pedaling, jumping, and "coasting and pumping," respectively. The dominant movement patterns investigated for the start, takeoff, landing, and pumping were hip (∼30 times per lap) and knee extension (~30 per leg per lap) and horizontal shoulder abduction and adduction (20 times per lap). Future research is needed to identify the power and acceleration profiles of the sport, which would be paramount for determining the best practice in testing and preparing BMX athletes. Exercises that specifically target the extensors of the hips, knees, and ankles and the muscles responsible for horizontal shoulder abduction and adduction are recommended.

  18. Semiactive field-controllable magneto-rheological fluid dampers for mountain bicycles

    NASA Astrophysics Data System (ADS)

    Breese, Darrell G.; Gordaninejad, Faramarz

    2000-06-01

    This paper presents the development and evaluation of field- controllable, semi-active magneto-rheological fluid (MRF) shock absorbers for a mountain bicycle. Recent trends in the bicycle industry show a movement towards semi-active suspension systems. Two new MRF dampers are designed and tested with the intent of being used on the front and rear suspension of a modern mountain bicycle. The MRF shock absorbers are designed to emulate the performance of the original equipment manufacturer shock absorbers in passive mode. Application of an input electric current to the MRF shock absorber causes a dramatic increase in the damping capacity. Procedures and results are presented for the design and experimental characterization of these MRF dampers.

  19. Practical Engineering Education and Local Contribution Through the Rental Project Using the Recycled Bicycle

    NASA Astrophysics Data System (ADS)

    Taniai, Tetsuyuki; Morita, Shou; Yokoyama, Tatsuki; Nishizaki, Yasushi

    In this report, we proposed the renovation project of a shopping street by the association with a local government, shop and college. The purposes of this project are as follows : (1) soft skills improvement of the college students (2) improvement of the motivation for learning of the college students (3) practical engineering education by the local contribution (4) reduction of carbon-dioxide emissions in the local area (5) effective use of facilities and equipment in the college. Providing some recycled bicycles, which made by the college students from the scrapped bicycle in the college, for the rental bicycle project, it makes a practical engineering education and local contribution opportunity for the college student.

  20. The role of bicycle sharing systems in normalising the image of cycling: An observational study of London cyclists

    PubMed Central

    Goodman, Anna; Green, Judith; Woodcock, James

    2014-01-01

    Bicycle sharing systems are increasingly popular around the world and have the potential to increase the visibility of people cycling in everyday clothing. This may in turn help normalise the image of cycling, and reduce perceptions that cycling is ‘risky’ or ‘only for sporty people’. This paper sought to compare the use of specialist cycling clothing between users of the London bicycle sharing system (LBSS) and cyclists using personal bicycles. To do this, we observed 3594 people on bicycles at 35 randomly-selected locations across central and inner London. The 592 LBSS users were much less likely to wear helmets (16% vs. 64% among personal-bicycle cyclists), high-visibility clothes (11% vs. 35%) and sports clothes (2% vs. 25%). In total, 79% of LBSS users wore none of these types of specialist cycling clothing, as compared to only 30% of personal-bicycle cyclists. This was true of male and female LBSS cyclists alike (all p>0.25 for interaction). We conclude that bicycle sharing systems may not only encourage cycling directly, by providing bicycles to rent, but also indirectly, by increasing the number and diversity of cycling ‘role models’ visible. PMID:25568838

  1. Outcomes of Home-Support Consultation on the Maintenance of Bicycle-Riding Skills for Youth with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Reynolds, Jennifer L.; Pitchford, E. Andrew; Hauck, Janet L.; Ketcheson, Leah R.; Ulrich, Dale A.

    2016-01-01

    Bicycle riding is a functional motor skill that increases physical activity opportunities, social interaction, and independence. However, bicycle riding is difficult for youth with autism spectrum disorder (ASD) to learn. This study examined the effectiveness of home-support consultation (HSC) on increasing the maintenance of independent bicycle…

  2. Perceiving and Acting on Complex Affordances: How Children and Adults Bicycle across Two Lanes of Opposing Traffic

    ERIC Educational Resources Information Center

    Grechkin, Timofey Y.; Chihak, Benjamin J.; Cremer, James F.; Kearney, Joseph K.; Plumert, Jodie M.

    2013-01-01

    This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous…

  3. Landau-like Atomic Problem on a Non-commutative Phase Space

    NASA Astrophysics Data System (ADS)

    Mamat, Jumakari; Dulat, Sayipjamal; Mamatabdulla, Hekim

    2016-06-01

    We study the motion of a neutral particle in symmetric gauge and in the framework of non-commutative Quantum Mechanics. Starting from the corresponding Hamiltonian we derive the eigenfunction and eigenvalues.

  4. 20 CFR 702.142 - Commutation of payments; aliens not residents or about to become nonresidents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... surviving spouse or child or children, to surviving father or mother whom the employee has supported, either..., OWCP, may, at his option, or upon the application of the insurance carrier he shall, commute all...

  5. Commute trip reduction in Washington: Base year worksite characteristics and programs

    SciTech Connect

    Dodds, D.

    1995-02-01

    Employers in Washington`s eight most populous counties are engaged in an effort to reduce their employees` use of single occupant automobiles for commuting. This report documents the status of those employers at the beginning of the Commute Trip Reduction (CTR) program as a basis for evaluating the impacts of the program. The first section provides a brief exploration of the Washington CTR Law and a history of the first steps in its implementation. The second section presents a summary of the characteristics of the worksites affected by the law. The CTR Law calls for reductions in single occupant vehicle (SOV) commuting and in vehicle miles traveled (VMT). The third section of this report presents baseline measurements of SOV and VMT and goals for reducing them. The fourth section provides summary information on the first year of programs employers planned to implement. The final section very briefly outlines actions the Commute Trip Reduction law calls for between 1995 and 1999.

  6. Proceedings of the Monterey Conference on Planning for Rotorcraft and Commuter Air Transportation

    NASA Technical Reports Server (NTRS)

    Stockwell, W. L.

    1983-01-01

    Planning and technological issues involved in rotorcraft and commuter fixed-wing air transportation are discussed. Subject areas include the future community environment, aircraft technology, community transportation planning, and regulatory perspectives.

  7. Research and technology program perspectives for general aviation and commuter aircraft

    NASA Technical Reports Server (NTRS)

    Bauchspies, J. S.; Simpson, W. E.

    1982-01-01

    The uses, benefits, and technology needs of the U.S. general aviation industry were studied in light of growing competition from foreign general aviation manufacturers, especially in the commuter and business jet aircraft markets.

  8. Quantum Groups, Non-Commutative Differential Geometry and Applications

    NASA Astrophysics Data System (ADS)

    Schupp, Peter

    The topic of this thesis is the development of a versatile and geometrically motivated differential calculus on non-commutative or quantum spaces, providing powerful but easy-to-use mathematical tools for applications in physics and related sciences. A generalization of unitary time evolution is proposed and studied for a simple 2-level system, leading to non-conservation of microscopic entropy, a phenomenon new to quantum mechanics. A Cartan calculus that combines functions, forms, Lie derivatives and inner derivations along general vector fields into one big algebra is constructed for quantum groups and then extended to quantum planes. The construction of a tangent bundle on a quantum group manifold and an BRST type approach to quantum group gauge theory are given as further examples of applications. The material is organized in two parts: Part I studies vector fields on quantum groups, emphasizing Hopf algebraic structures, but also introducing a 'quantum geometric' construction. Using a generalized semi-direct product construction we combine the dual Hopf algebras {cal A} of functions and {cal U} of left-invariant vector fields into one fully bicovariant algebra of differential operators. The pure braid group is introduced as the commutant of Delta({cal U}). It provides invariant maps {cal A} to{cal U} and thereby bicovariant vector fields, casimirs and metrics. This construction allows the translation of undeformed matrix expressions into their less obvious quantum algebraic counter parts. We study this in detail for quasitriangular Hopf algebras, giving the determinant and orthogonality relation for the 'reflection' matrix. Part II considers the additional structures of differential forms and finitely generated quantum Lie algebras--it is devoted to the construction of the Cartan calculus, based on an undeformed Cartan identity. We attempt a classification of various types of quantum Lie algebras and present a fairly general example for their construction

  9. Bicycle-Related Injuries Presenting to Tabriz Imam Reza Hospital, Iran

    PubMed Central

    Shams Vahdati, Samad; Rajaei Ghafouri, Rouzbeh; Razavi, Sajjad; Mazouchian, Hossein

    2016-01-01

    Background Rising fuel cost and subsequent increase in transportation prices encourage people to use cheap transportation such as a bicycle. This vehicle can also be used for sports and recreation. Bicycles are widely used in Iran, like other countries. There is not enough data about bicycle-related traumas in our country. Objectives The aim of this study was to obtain the epidemiology of this type of injury in Tabriz Imam Reza Hospital as a referral center in northwest of Iran during 2009 to 2012. Materials and Methods One hundred bicycle-related patients during the three years were entered in this descriptive cross-sectional study. Patient’s demographics, place and time of crash, mechanism of trauma, helmet and other safety device usage, and disposition information were gathered by a researcher-made checklist. Admission rate and ward as well as the site of injuries were also collected. The data were analyzed by SPSS 16 software using descriptive statistics. Results All the patients were males with a mean age of 31.3 ± 23.12. Seventy six bicycle-related injuries occurred during weekdays and 24 happened on holidays; 71 patients attended the emergency department in the morning and 29 at night. Only three of 100 cyclists had helmets during the accident. The rates of injuries were as follows: 65 head and face, 20 abdomen, 14 chest, 11 soft tissue, eight lower limb, eight cervical spine, six upper limb, four thoracic and lumbar spine, and three pelvis injuries. Conclusions Head and face are the most common sites of injury and skull fracture is the most common one. Considering the preventable entity of trauma, the use of helmets seems to be beneficial to prevent most bicycle-related injuries. PMID:27626000

  10. Bicycle-Related Injuries Presenting to Tabriz Imam Reza Hospital, Iran

    PubMed Central

    Shams Vahdati, Samad; Rajaei Ghafouri, Rouzbeh; Razavi, Sajjad; Mazouchian, Hossein

    2016-01-01

    Background Rising fuel cost and subsequent increase in transportation prices encourage people to use cheap transportation such as a bicycle. This vehicle can also be used for sports and recreation. Bicycles are widely used in Iran, like other countries. There is not enough data about bicycle-related traumas in our country. Objectives The aim of this study was to obtain the epidemiology of this type of injury in Tabriz Imam Reza Hospital as a referral center in northwest of Iran during 2009 to 2012. Materials and Methods One hundred bicycle-related patients during the three years were entered in this descriptive cross-sectional study. Patient’s demographics, place and time of crash, mechanism of trauma, helmet and other safety device usage, and disposition information were gathered by a researcher-made checklist. Admission rate and ward as well as the site of injuries were also collected. The data were analyzed by SPSS 16 software using descriptive statistics. Results All the patients were males with a mean age of 31.3 ± 23.12. Seventy six bicycle-related injuries occurred during weekdays and 24 happened on holidays; 71 patients attended the emergency department in the morning and 29 at night. Only three of 100 cyclists had helmets during the accident. The rates of injuries were as follows: 65 head and face, 20 abdomen, 14 chest, 11 soft tissue, eight lower limb, eight cervical spine, six upper limb, four thoracic and lumbar spine, and three pelvis injuries. Conclusions Head and face are the most common sites of injury and skull fracture is the most common one. Considering the preventable entity of trauma, the use of helmets seems to be beneficial to prevent most bicycle-related injuries.

  11. Exposure to traffic pollution, acute inflammation and autonomic response in a panel of car commuters

    PubMed Central

    Sarnat, Jeremy A.; Golan, Rachel; Greenwald, Roby; Raysoni, Amit U.; Kewada, Priya; Winquist, Andrea; Sarnat, Stefanie E.; Flanders, W. Dana; Mirabelli, Maria C.; Zora, Jennifer E.; Bergin, Michael H.; Yip, Fuyuen

    2015-01-01

    Background Exposure to traffic pollution has been linked to numerous adverse health endpoints. Despite this, limited data examining traffic exposures during realistic commutes and acute response exists. Objectives: We conducted the Atlanta Commuters Exposures (ACE-1) Study, an extensive panel-based exposure and health study, to measure chemically-resolved in-vehicle exposures and corresponding changes in acute oxidative stress, lipid peroxidation, pulmonary and systemic inflammation and autonomic response. Methods We recruited 42 adults (21 with and 21 without asthma) to conduct two 2-h scripted highway commutes during morning rush hour in the metropolitan Atlanta area. A suite of in-vehicle particulate components were measured in the subjects’ private vehicles. Biomarker measurements were conducted before, during, and immediately after the commutes and in 3 hourly intervals after commutes. Results At measurement time points within 3 h after the commute, we observed mild to pronounced elevations relative to baseline in exhaled nitric oxide, C-reactive-protein, and exhaled malondialdehyde, indicative of pulmonary and systemic inflammation and oxidative stress initiation, as well as decreases relative to baseline levels in the time-domain heart-rate variability parameters, SDNN and rMSSD, indicative of autonomic dysfunction. We did not observe any detectable changes in lung function measurements (FEV1, FVC), the frequency-domain heart-rate variability parameter or other systemic biomarkers of vascular injury. Water soluble organic carbon was associated with changes in eNO at all post-commute time-points (p < 0.0001). Conclusions Our results point to measureable changes in pulmonary and autonomic biomarkers following a scripted 2-h highway commute. PMID:24906070

  12. Current-bounded commutation of a long-stroke magnetically levitated stage with moving coils

    NASA Astrophysics Data System (ADS)

    Zhu, Yu; Zhang, Shengguo; Yang, Kaiming; Mu, Haihua; Yin, Wensheng

    2012-11-01

    Magnetically levitated stages(MLS) have potentials to obtain good motion performances in high vacuum environment. Yet the electromagnetic forces/torques corresponding to six degrees of freedom(DOF) motions have coupling relationship with each current of coil array, and this coupling is still associated with the relative positions between the mover and the stator of the stage. So it is quite difficult to control the 6-DOF motions of the stage. By reasonable commutation of coil array, this complicated coupling relationship can be decoupled. The analytical force/torque-decomposing model of the stage is established first. Then the initial currents of coil array are commutated based on the pseudo inverse of the analytical force/torque-decomposing model matrix. And then the coil array currents are commutated again with different current bounds given to the initial currents as well as in the sense of minimum 2-norm of currents vector. Using the long stroke magnetically levitated stage with moving coils under investigation as examples, the currents of coil array are commutated with different current bounds adopting the proposed commutation method, the determination of current bound and the current bounds' influences on the heat-losses in coil array are analyzed, and the effectiveness of implementation algorithm of proposed commutation method is discussed. Simulation, analysis and discussion results indicate that the currents of coil array within the given current bound can be solved analytically by proposed commutation method, and the implementation algorithm does not need any searching or iteration. By the current-bounded commutation method proposed, the amplitude of coil array currents can be limited within an appropriate current bound(This is very beneficial to the improvement of the reliability and motion performance of the stage), as well as these currents can also generate the desired forces and torques.

  13. Student's exposure to volatile organic compounds while commuting by motorcycle and bus in Taipei City

    SciTech Connect

    Chan, C.C.; Lin, S.H.; Her, G.R. )

    1993-09-01

    This study examined student's exposure to volatile organic compounds (VOCs) while commuting by bus and motorcycle in Taipei, Taiwan in the winter of 1992. A total of 19 target C5-C10 VOCs on three most frequently used commuting routes were collected on Tenax-GC adsorbent tubes. The VOCs were desorbed by thermal desorption method and analyzed by GC-MS. The most abundant VOC exposure experienced by commuters was to toluene. Several alkylated benzenes, such as propyl benzenes, ethyl-methyl-benzenes and trimethyl-benzenes, were relatively abundant on the roads in Taipei. The mean benzene concentration measured in buses was 173 micrograms/m3 and motorcycles. On the average, the commuters in Taipei experienced about three to eight times higher VOC concentrations than the commuters in Los Angeles, California. Higher VOC concentrations were measured on motorcycles than in buses. The VOC concentrations were not significantly different between morning and afternoon commutes, nor among the three commuting routes. VOC concentrations measured in classroom at three schools in downtown Taipei did not vary significantly on each sampling day. However, at each school the in-classroom VOC concentrations varied significantly over the six consecutive sampling days. The VOC concentrations measured on the roads were about five times higher than those measured in the school classrooms in the city. Moderate to high correlations were found among most of the measurements of the 19 VOCs. The survey questionnaire indicated that daily commuting time ranged from 45 minutes for elementary school students to 95 minutes for vocational school students.

  14. Regularization of two-dimensional supersymmetric Yang-Mills theory via non-commutative geometry

    NASA Astrophysics Data System (ADS)

    Valavane, K.

    2000-11-01

    The non-commutative geometry is a possible framework to regularize quantum field theory in a non-perturbative way. This idea is an extension of the lattice approximation by non-commutativity that allows us to preserve symmetries. The supersymmetric version is also studied and more precisely in the case of the Schwinger model on a supersphere. This paper is a generalization of this latter work to more general gauge groups.

  15. Orthogonal ring-closing alkyne and olefin metathesis for the synthesis of small GTPase-targeting bicyclic peptides.

    PubMed

    Cromm, Philipp M; Schaubach, Sebastian; Spiegel, Jochen; Fürstner, Alois; Grossmann, Tom N; Waldmann, Herbert

    2016-04-14

    Bicyclic peptides are promising scaffolds for the development of inhibitors of biological targets that proved intractable by typical small molecules. So far, access to bioactive bicyclic peptide architectures is limited due to a lack of appropriate orthogonal ring-closing reactions. Here, we report chemically orthogonal ring-closing olefin (RCM) and alkyne metathesis (RCAM), which enable an efficient chemo- and regioselective synthesis of complex bicyclic peptide scaffolds with variable macrocycle geometries. We also demonstrate that the formed alkyne macrocycle can be functionalized subsequently. The orthogonal RCM/RCAM system was successfully used to evolve a monocyclic peptide inhibitor of the small GTPase Rab8 into a bicyclic ligand. This modified peptide shows the highest affinity for an activated Rab GTPase that has been reported so far. The RCM/RCAM-based formation of bicyclic peptides provides novel opportunities for the design of bioactive scaffolds suitable for the modulation of challenging protein targets.

  16. Orthogonal ring-closing alkyne and olefin metathesis for the synthesis of small GTPase-targeting bicyclic peptides

    PubMed Central

    Cromm, Philipp M.; Schaubach, Sebastian; Spiegel, Jochen; Fürstner, Alois; Grossmann, Tom N.; Waldmann, Herbert

    2016-01-01

    Bicyclic peptides are promising scaffolds for the development of inhibitors of biological targets that proved intractable by typical small molecules. So far, access to bioactive bicyclic peptide architectures is limited due to a lack of appropriate orthogonal ring-closing reactions. Here, we report chemically orthogonal ring-closing olefin (RCM) and alkyne metathesis (RCAM), which enable an efficient chemo- and regioselective synthesis of complex bicyclic peptide scaffolds with variable macrocycle geometries. We also demonstrate that the formed alkyne macrocycle can be functionalized subsequently. The orthogonal RCM/RCAM system was successfully used to evolve a monocyclic peptide inhibitor of the small GTPase Rab8 into a bicyclic ligand. This modified peptide shows the highest affinity for an activated Rab GTPase that has been reported so far. The RCM/RCAM-based formation of bicyclic peptides provides novel opportunities for the design of bioactive scaffolds suitable for the modulation of challenging protein targets. PMID:27075966

  17. Orthogonal ring-closing alkyne and olefin metathesis for the synthesis of small GTPase-targeting bicyclic peptides.

    PubMed

    Cromm, Philipp M; Schaubach, Sebastian; Spiegel, Jochen; Fürstner, Alois; Grossmann, Tom N; Waldmann, Herbert

    2016-01-01

    Bicyclic peptides are promising scaffolds for the development of inhibitors of biological targets that proved intractable by typical small molecules. So far, access to bioactive bicyclic peptide architectures is limited due to a lack of appropriate orthogonal ring-closing reactions. Here, we report chemically orthogonal ring-closing olefin (RCM) and alkyne metathesis (RCAM), which enable an efficient chemo- and regioselective synthesis of complex bicyclic peptide scaffolds with variable macrocycle geometries. We also demonstrate that the formed alkyne macrocycle can be functionalized subsequently. The orthogonal RCM/RCAM system was successfully used to evolve a monocyclic peptide inhibitor of the small GTPase Rab8 into a bicyclic ligand. This modified peptide shows the highest affinity for an activated Rab GTPase that has been reported so far. The RCM/RCAM-based formation of bicyclic peptides provides novel opportunities for the design of bioactive scaffolds suitable for the modulation of challenging protein targets. PMID:27075966

  18. Device and method to determine perineal artery occlusion during road bicycling.

    PubMed

    Parthiban, Sujeeth; Hotaling, James M; Ohlander, Samuel J; Baftiri, Amit P; Freels, Sally; Niederberger, Craig S

    2014-01-01

    Greater than 60 million American men who ride bicycles are at risk of developing erectile dysfunction. One possible reason is occlusion of the perineal arteries. Researchers relied on indirect methods and stationary models to study this problem. We developed a novel system to quantify occlusion among bicycle riders during a road bike ride. Our verification and validation activities show that this system can be safely used on human subjects to measure perineal artery occlusion. The method described in this paper provides a valuable tool to the researchers to study or to develop new solutions that alleviate this problem. The outcomes of these efforts will help millions of cyclists worldwide.

  19. Mapping cyclist activity and injury risk in a network combining smartphone GPS data and bicycle counts.

    PubMed

    Strauss, Jillian; Miranda-Moreno, Luis F; Morency, Patrick

    2015-10-01

    In recent years, the modal share of cycling has been growing in North American cities. With the increase of cycling, the need of bicycle infrastructure and road safety concerns have also raised. Bicycle flows are an essential component in safety analysis. The main objective of this work is to propose a methodology to estimate and map bicycle volumes and cyclist injury risk throughout the entire network of road segments and intersections on the island of Montreal, achieved by combining smartphone GPS traces and count data. In recent years, methods have been proposed to estimate average annual daily bicycle (AADB) volume and injury risk estimates at both the intersection and segment levels using bicycle counts. However, these works have been limited to small samples of locations for which count data is available. In this work, a methodology is proposed to combine short- and long-term bicycle counts with GPS data to estimate AADB volumes along segments and intersections in the entire network. As part of the validation process, correlation is observed between AADB values obtained from GPS data and AADB values from count data, with R-squared values of 0.7 for signalized intersections, 0.58 for non-signalized intersections and between 0.48 and 0.76 for segments with and without bicycle infrastructure. The methodology is also validated through the calibration of safety performance functions using both sources of AADB estimates, from counts and from GPS data. Using the validated AADB estimates, the factors associated with injury risk were identified using data from the entire population of intersections and segments throughout Montreal. Bayesian injury risk maps are then generated and the concentrations of expected injuries and risk at signalized intersections are identified. Signalized intersections, which are often located at the intersection of major arterials, witness 4 times more injuries and 2.5 times greater risk than non-signalized intersections. A similar

  20. Device and method to determine perineal artery occlusion during road bicycling.

    PubMed

    Parthiban, Sujeeth; Hotaling, James M; Ohlander, Samuel J; Baftiri, Amit P; Freels, Sally; Niederberger, Craig S

    2014-01-01

    Greater than 60 million American men who ride bicycles are at risk of developing erectile dysfunction. One possible reason is occlusion of the perineal arteries. Researchers relied on indirect methods and stationary models to study this problem. We developed a novel system to quantify occlusion among bicycle riders during a road bike ride. Our verification and validation activities show that this system can be safely used on human subjects to measure perineal artery occlusion. The method described in this paper provides a valuable tool to the researchers to study or to develop new solutions that alleviate this problem. The outcomes of these efforts will help millions of cyclists worldwide. PMID:25570811

  1. Risky riding: Naturalistic methods comparing safety behavior from conventional bicycle riders and electric bike riders.

    PubMed

    Langford, Brian Casey; Chen, Jiaoli; Cherry, Christopher R

    2015-09-01

    As electric bicycles (e-bikes) have emerged as a new transportation mode, their role in transportation systems and their impact on users have become important issues for policy makers and engineers. Little safety-related research has been conducted in North America or Europe because of their relatively small numbers. This work describes the results of a naturalistic GPS-based safety study between regular bicycle (i.e., standard bicycle) and e-bike riders in the context of a unique bikesharing system that allows comparisons between instrumented bike technologies. We focus on rider safety behavior under four situations: (1) riding in the correct direction on directional roadway segments, (2) speed on on-road and shared use paths, (3) stopping behavior at stop-controlled intersections, and (4) stopping behavior at signalized intersections. We find that, with few exceptions, riders of e-bike behave very similarly to riders of bicycles. Violation rates were very high for both vehicles. Riders of regular bicycles and e-bikes both ride wrong-way on 45% and 44% of segments, respectively. We find that average on-road speeds of e-bike riders (13.3kph) were higher than regular bicyclists (10.4kph) but shared use path (greenway) speeds of e-bike riders (11.0kph) were lower than regular bicyclists (12.6kph); both significantly different at >95% confidence. At stop control intersections, both bicycle and e-bike riders violate the stop signs at the similar rate with bicycles violating stop signs at a slightly higher rate at low speed thresholds (∼80% violations at 6kph, 40% violations at 11kph). Bicycles and e-bikes violate traffic signals at similar rates (70% violation rate). These findings suggest that, among the same population of users, e-bike riders exhibit nearly identical safety behavior as regular bike riders and should be regulated in similar ways. Users of both technologies have very high violation rates of traffic control devices and interventions should occur to

  2. Bicycle-related genitourinary injuries in the USA from 2002–2010

    PubMed Central

    Tasian, Gregory E; Appa, Ayesha A; Bagga, Herman S; Blaschko, Sarah; McCulloch, Charles E; McAninch, Jack W; Breyer, Benjamin N

    2014-01-01

    Among children, the incidence of bicycle-related genitourinary (GU) injuries was 448 per 100 000 (95% CI 383 to 514) and, among adults, was 53 per 100 000 (95% CI 36 to 71). Although children sustained more injuries, adults were more likely to being admitted to the hospital for the GU injury (OR 1.95, 95% CI 1.13 to 3.37). Children sustain nearly 10 times more GU injuries due to bicycles than adults, but adults have higher odds of sustaining injuries requiring admission. PMID:24618096

  3. Mapping cyclist activity and injury risk in a network combining smartphone GPS data and bicycle counts.

    PubMed

    Strauss, Jillian; Miranda-Moreno, Luis F; Morency, Patrick

    2015-10-01

    In recent years, the modal share of cycling has been growing in North American cities. With the increase of cycling, the need of bicycle infrastructure and road safety concerns have also raised. Bicycle flows are an essential component in safety analysis. The main objective of this work is to propose a methodology to estimate and map bicycle volumes and cyclist injury risk throughout the entire network of road segments and intersections on the island of Montreal, achieved by combining smartphone GPS traces and count data. In recent years, methods have been proposed to estimate average annual daily bicycle (AADB) volume and injury risk estimates at both the intersection and segment levels using bicycle counts. However, these works have been limited to small samples of locations for which count data is available. In this work, a methodology is proposed to combine short- and long-term bicycle counts with GPS data to estimate AADB volumes along segments and intersections in the entire network. As part of the validation process, correlation is observed between AADB values obtained from GPS data and AADB values from count data, with R-squared values of 0.7 for signalized intersections, 0.58 for non-signalized intersections and between 0.48 and 0.76 for segments with and without bicycle infrastructure. The methodology is also validated through the calibration of safety performance functions using both sources of AADB estimates, from counts and from GPS data. Using the validated AADB estimates, the factors associated with injury risk were identified using data from the entire population of intersections and segments throughout Montreal. Bayesian injury risk maps are then generated and the concentrations of expected injuries and risk at signalized intersections are identified. Signalized intersections, which are often located at the intersection of major arterials, witness 4 times more injuries and 2.5 times greater risk than non-signalized intersections. A similar

  4. Knights of death: introducing bicycles and motor vehicles to Turin, 1890-1907.

    PubMed

    Moraglio, Massimo

    2015-04-01

    The aim of this article is to investigate, through a case study from the city of Turin, the reaction to the arrival of bicycles and automobiles in Italy. It focuses on the early years of bicycle and automobile use, using municipal council minutes, local newspapers, and satirical magazines as sources. The introduction of velocipedes and cars disrupted the traditional use of roads as public spaces, generating protests against the new transport devices, especially with regard to safety concerns resulting from the transgression of traditional uses of urban streets, the speed of vehicles, and the anonymity of riders and drivers. PMID:26005084

  5. Risky riding: Naturalistic methods comparing safety behavior from conventional bicycle riders and electric bike riders.

    PubMed

    Langford, Brian Casey; Chen, Jiaoli; Cherry, Christopher R

    2015-09-01

    As electric bicycles (e-bikes) have emerged as a new transportation mode, their role in transportation systems and their impact on users have become important issues for policy makers and engineers. Little safety-related research has been conducted in North America or Europe because of their relatively small numbers. This work describes the results of a naturalistic GPS-based safety study between regular bicycle (i.e., standard bicycle) and e-bike riders in the context of a unique bikesharing system that allows comparisons between instrumented bike technologies. We focus on rider safety behavior under four situations: (1) riding in the correct direction on directional roadway segments, (2) speed on on-road and shared use paths, (3) stopping behavior at stop-controlled intersections, and (4) stopping behavior at signalized intersections. We find that, with few exceptions, riders of e-bike behave very similarly to riders of bicycles. Violation rates were very high for both vehicles. Riders of regular bicycles and e-bikes both ride wrong-way on 45% and 44% of segments, respectively. We find that average on-road speeds of e-bike riders (13.3kph) were higher than regular bicyclists (10.4kph) but shared use path (greenway) speeds of e-bike riders (11.0kph) were lower than regular bicyclists (12.6kph); both significantly different at >95% confidence. At stop control intersections, both bicycle and e-bike riders violate the stop signs at the similar rate with bicycles violating stop signs at a slightly higher rate at low speed thresholds (∼80% violations at 6kph, 40% violations at 11kph). Bicycles and e-bikes violate traffic signals at similar rates (70% violation rate). These findings suggest that, among the same population of users, e-bike riders exhibit nearly identical safety behavior as regular bike riders and should be regulated in similar ways. Users of both technologies have very high violation rates of traffic control devices and interventions should occur to

  6. Transport priorities, risk perception and worry associated with mode use and preferences among Norwegian commuters.

    PubMed

    Nordfjærn, Trond; Simşekoğlu, Özlem; Lind, Hans Brende; Jørgensen, Stig Halvard; Rundmo, Torbjørn

    2014-11-01

    There is currently scant research on the role of transport priorities, risk perception and worry for travel mode use and preferences. The present study aims to examine these factors in relation to mode use and preferences among Norwegian commuters. A web-based survey was conducted in a randomly obtained representative sample of daily commuters in the extended greater Oslo area (n=690). The results showed that those who prioritized efficiency and flexibility tended to commute by car, while those who prioritized safety and comfort used public (e.g. metro, tram, and train) or active (e.g. walking and cycling) transport. In a free choice scenario, the respondents who prioritized flexibility reported a preference for using a car, whereas those who prioritized safety and comfort preferred public and active transport for their commuter travels. Risk perception of high impact events, such as terrorism and major accidents, as well as risk perception related to personal impact risks (theft, violence etc.) were related to car use on commuter travels. Transport-related worry exerted weak influences on mode use and preferences. Increased speed on rail transport and more frequent departures may be effective in reducing car use on commuter travels. Risk communication should focus on highlighting the low risk of experiencing security and safety issues in the public transport sector, and this message should be complemented by efforts to reduce the probability of negative events affecting public transport.

  7. Quantization maps, algebra representation, and non-commutative Fourier transform for Lie groups

    SciTech Connect

    Guedes, Carlos; Oriti, Daniele; Raasakka, Matti

    2013-08-15

    The phase space given by the cotangent bundle of a Lie group appears in the context of several models for physical systems. A representation for the quantum system in terms of non-commutative functions on the (dual) Lie algebra, and a generalized notion of (non-commutative) Fourier transform, different from standard harmonic analysis, has been recently developed, and found several applications, especially in the quantum gravity literature. We show that this algebra representation can be defined on the sole basis of a quantization map of the classical Poisson algebra, and identify the conditions for its existence. In particular, the corresponding non-commutative star-product carried by this representation is obtained directly from the quantization map via deformation quantization. We then clarify under which conditions a unitary intertwiner between such algebra representation and the usual group representation can be constructed giving rise to the non-commutative plane waves and consequently, the non-commutative Fourier transform. The compact groups U(1) and SU(2) are considered for different choices of quantization maps, such as the symmetric and the Duflo map, and we exhibit the corresponding star-products, algebra representations, and non-commutative plane waves.

  8. Modeling the Commuting Travel Activities within Historic Districts in Chinese Cities

    PubMed Central

    Yin, Fengjun; Hu, Qizhou

    2014-01-01

    The primary objective of this study is to analyze the characteristics of commuting activities within the historical districts in cities of China. The impacts of various explanatory variables on commuters' travels are evaluated using the structural equation modeling (SEM) approach. The household survey was conducted in the historical districts in Yangzhou, China. Based on the data, various individual and household attributes were considered exogenous variables, while the subsistence activity characteristics, travel times, numbers of three typical home-based trip chains, trip chains, and travel mode were considered as the endogenous variables. Commuters in our study were classified into two main groups according to their working location, which were the commuters in the historic district and those out of the district. The modeling results show that several individual and household attributes of commuters in historic district have significant impacts on the characteristics of travel activities. Additionally, the characteristics of travel activities within the two groups are quite different, and the contributing factors related to commuting travels are different as well. PMID:25435864

  9. Transport priorities, risk perception and worry associated with mode use and preferences among Norwegian commuters.

    PubMed

    Nordfjærn, Trond; Simşekoğlu, Özlem; Lind, Hans Brende; Jørgensen, Stig Halvard; Rundmo, Torbjørn

    2014-11-01

    There is currently scant research on the role of transport priorities, risk perception and worry for travel mode use and preferences. The present study aims to examine these factors in relation to mode use and preferences among Norwegian commuters. A web-based survey was conducted in a randomly obtained representative sample of daily commuters in the extended greater Oslo area (n=690). The results showed that those who prioritized efficiency and flexibility tended to commute by car, while those who prioritized safety and comfort used public (e.g. metro, tram, and train) or active (e.g. walking and cycling) transport. In a free choice scenario, the respondents who prioritized flexibility reported a preference for using a car, whereas those who prioritized safety and comfort preferred public and active transport for their commuter travels. Risk perception of high impact events, such as terrorism and major accidents, as well as risk perception related to personal impact risks (theft, violence etc.) were related to car use on commuter travels. Transport-related worry exerted weak influences on mode use and preferences. Increased speed on rail transport and more frequent departures may be effective in reducing car use on commuter travels. Risk communication should focus on highlighting the low risk of experiencing security and safety issues in the public transport sector, and this message should be complemented by efforts to reduce the probability of negative events affecting public transport. PMID:25129446

  10. Lightweight diesel engine designs for commuter type aircraft

    NASA Technical Reports Server (NTRS)

    Brouwers, A. P.

    1981-01-01

    Conceptual designs and performance of advanced technology lightweight diesel engines, suitable for commuter type aircraft power plants are defined. Two engines are discussed, a 1491 kW (2000 SHP) eight-cylinder engine and a 895 kW (1200 SHP) six-cylinder engine. High performance and related advanced technologies are proposed such as insulated cylinders, very high injection pressures and high compressor and turbine efficiencies. The description of each engine includes concept drawings, a performance analysis, and weight data. Fuel flow data are given for full and partial power up to 7620m altitude. The performance data are also extrapolated over a power range from 671 kW(900SHP) to 1864 kW (2500 SHP). The specific fuel consumption of the 1491 kW (2000 SHP) engine is 182 g/hWh (.299 lb/HPh) at cruise altitude, its weight 620 kg (1365 lb.) and specific weight .415 kg/kW (.683 lb/HP). The specific fuel consumption of the 895 kW (1200 SHP) engine is 187 g/hWh (.308 lb/HPh) at cruise altitude, its weight 465 kg (1025 lb.) and specific weight .520 kg/kW (.854 lb/HP).

  11. Study of advanced rotary combustion engines for commuter aircraft

    NASA Technical Reports Server (NTRS)

    Berkowitz, M.; Jones, C.; Myers, D.

    1983-01-01

    Performance, weight, size, and maintenance data for advanced rotary aircraft engines suitable for comparative commuter aircraft system evaluation studies of alternate engine candidates are provided. These are turbocharged, turbocompounded, direct injected, stratified charge rotary engines. Hypothetical engines were defined (an RC4-74 at 895 kW and an RC6-87 at 1490 kW) based on the technologies and design approaches used in the highly advanced engine of a study of advanced general aviation rotary engines. The data covers the size range of shaft power from 597 kW (800 hp) to 1865 kW (2500 hp) and is in the form of drawings, tables, curves and written text. These include data on internal geometry and configuration, installation information, turbocharging and turbocompounding arrangements, design features and technologies, engine cooling, fuels, scaling for weight size BSFC and heat rejection for varying horsepower, engine operating and performance data, and TBO and maintenance requirements. The basic combustion system was developed and demonstrated; however the projected power densities and performance efficiencies require increases in engine internal pressures, thermal loading, and rotative speed.

  12. Factors associated with active commuting to work among women.

    PubMed

    Bopp, Melissa; Child, Stephanie; Campbell, Matthew

    2014-01-01

    Active commuting (AC), the act of walking or biking to work, has notable health benefits though rates of AC remain low among women. This study used a social-ecological framework to examine the factors associated with AC among women. A convenience sample of employed, working women (n = 709) completed an online survey about their mode of travel to work. Individual, interpersonal, institutional, community, and environmental influences were assessed. Basic descriptive statistics and frequencies described the sample. Simple logistic regression models examined associations with the independent variables with AC participation and multiple logistic regression analysis determined the relative influence of social ecological factors on AC participation. The sample was primarily middle-aged (44.09±11.38 years) and non-Hispanic White (92%). Univariate analyses revealed several individual, interpersonal, institutional, community and environmental factors significantly associated with AC. The multivariable logistic regression analysis results indicated that significant factors associated with AC included number of children, income, perceived behavioral control, coworker AC, coworker AC normative beliefs, employer and community supports for AC, and traffic. The results of this study contribute to the limited body of knowledge on AC participation for women and may help to inform gender-tailored interventions to enhance AC behavior and improve health.

  13. A lightweight electronically commutated dc motor for electric passenger vehicles

    NASA Technical Reports Server (NTRS)

    Echolds, E. F.; Walla, P. S.

    1982-01-01

    A functional model breadboard converter and a rare-earth-cobalt, permanent magnet motor; as well as an engineering model converter and PM motor suitable for vehicle installations were developed and tested. The converter and motor achieved an 88% peak efficiency, a maximum output of 26 kW at 26,000 rpm, and a continuous rating of 15 kW. The system also generated power to the source during braking, with a demonstrated peak power available at the converter terminals of approximately 26 kW at 88% efficiency. Major conclusions include: (1) the SAE J227a(D) driving cycle efficiency for the converter/motor is 86% to 88% when energy available for recovery at the converter terminals is included; (2) the converter initial cost is approximately five times that of the permanent magnet motor, but can be reduced by means of LSI logic and integrated liquid cooled semiconductor packages; and (3) an electronically commutated motor with a liquid cooled converter will operate reliably without service or maintenance for the life of a passenger vehicle.

  14. Representations of Canonical Commutation Relations Describing Infinite Coherent States

    NASA Astrophysics Data System (ADS)

    Joye, Alain; Merkli, Marco

    2016-10-01

    We investigate the infinite volume limit of quantized photon fields in multimode coherent states. We show that for states containing a continuum of coherent modes, it is mathematically and physically natural to consider their phases to be random and identically distributed. The infinite volume states give rise to Hilbert space representations of the canonical commutation relations which we construct concretely. In the case of random phases, the representations are random as well and can be expressed with the help of Itô stochastic integrals. We analyze the dynamics of the infinite state alone and the open system dynamics of small systems coupled to it. We show that under the free field dynamics, initial phase distributions are driven to the uniform distribution. We demonstrate that coherences in small quantum systems, interacting with the infinite coherent state, exhibit Gaussian time decay. The decoherence is qualitatively faster than the one caused by infinite thermal states, which is known to be exponentially rapid only. This emphasizes the classical character of coherent states.

  15. Computational quantum-classical boundary of noisy commuting quantum circuits.

    PubMed

    Fujii, Keisuke; Tamate, Shuhei

    2016-01-01

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region. PMID:27189039

  16. Computational quantum-classical boundary of noisy commuting quantum circuits

    NASA Astrophysics Data System (ADS)

    Fujii, Keisuke; Tamate, Shuhei

    2016-05-01

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region.

  17. Factors associated with active commuting to work among women.

    PubMed

    Bopp, Melissa; Child, Stephanie; Campbell, Matthew

    2014-01-01

    Active commuting (AC), the act of walking or biking to work, has notable health benefits though rates of AC remain low among women. This study used a social-ecological framework to examine the factors associated with AC among women. A convenience sample of employed, working women (n = 709) completed an online survey about their mode of travel to work. Individual, interpersonal, institutional, community, and environmental influences were assessed. Basic descriptive statistics and frequencies described the sample. Simple logistic regression models examined associations with the independent variables with AC participation and multiple logistic regression analysis determined the relative influence of social ecological factors on AC participation. The sample was primarily middle-aged (44.09±11.38 years) and non-Hispanic White (92%). Univariate analyses revealed several individual, interpersonal, institutional, community and environmental factors significantly associated with AC. The multivariable logistic regression analysis results indicated that significant factors associated with AC included number of children, income, perceived behavioral control, coworker AC, coworker AC normative beliefs, employer and community supports for AC, and traffic. The results of this study contribute to the limited body of knowledge on AC participation for women and may help to inform gender-tailored interventions to enhance AC behavior and improve health. PMID:24512572

  18. Computational quantum-classical boundary of noisy commuting quantum circuits

    PubMed Central

    Fujii, Keisuke; Tamate, Shuhei

    2016-01-01

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region. PMID:27189039

  19. The Effects of Prompting and Reinforcement on Safe Behavior of Bicycle and Motorcycle Riders

    ERIC Educational Resources Information Center

    Okinaka, Takeru; Shimazaki, Tsuneo

    2011-01-01

    A reversal design was used to evaluate the effects of vocal and written prompts as well as reinforcement on safe behavior (dismounting and walking bicycles or motorcycles on a sidewalk) on a university campus. Results indicated that an intervention that consisted of vocal and written prompts and reinforcement delivered by security guards was…

  20. 11. DETAIL VIEW OF RIVER BANK AND PEDESTRIAN/BICYCLE PATH UNDER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF RIVER BANK AND PEDESTRIAN/BICYCLE PATH UNDER THE GLENDALE BOULEVARD (FOREGROUND) AND HYPERION BOULEVARD OVERCROSSINGS. LOOKING SOUTH. - Glendale-Hyperion Viaduct, Spanning Golden State Freeway (I-5) & Los Angeles River at Glendale Boulevard, Los Angeles, Los Angeles County, CA