Sample records for taxiing

  1. Comparison of Taxi Time Prediction Performance Using Different Taxi Speed Decision Trees

    NASA Technical Reports Server (NTRS)

    Lee, Hanbong

    2017-01-01

    In the STBO modeler and tactical surface scheduler for ATD-2 project, taxi speed decision trees are used to calculate the unimpeded taxi times of flights taxiing on the airport surface. The initial taxi speed values in these decision trees did not show good prediction accuracy of taxi times. Using the more recent, reliable surveillance data, new taxi speed values in ramp area and movement area were computed. Before integrating these values into the STBO system, we performed test runs using live data from Charlotte airport, with different taxi speed settings: 1) initial taxi speed values and 2) new ones. Taxi time prediction performance was evaluated by comparing various metrics. The results show that the new taxi speed decision trees can calculate the unimpeded taxi-out times more accurately.

  2. Taxi 'sugar daddies' and taxi queens: male taxi driver attitudes regarding transactional relationships in the Western Cape, South Africa.

    PubMed

    Potgieter, Cheryl; Strebel, Anna; Shefer, Tamara; Wagner, Claire

    2012-11-01

    Media reports are emerging on the phenomenon of young girls who travel with older mini-bus taxi drivers, and who are thought to have sex with the drivers in exchange for gifts and money. The extent to which such relationships might facilitate unsafe sexual practices and increased risks for both the men and the young women, often referred to as taxi queens, remains an important question in the light of the current challenges of HIV/AIDS in sub-Saharan Africa. However, very little research has been undertaken on this issue, especially regarding the perceptions and experiences of taxi drivers. Thus this paper aims to provide some preliminary findings on taxi drivers' attitudes and beliefs about taxi queens and their relationships with taxi drivers. A 22-item questionnaire was administered to 223 male taxi drivers in two regions in the Western Cape Province, South Africa. Taxi drivers in this study largely saw the relationship between taxi drivers and the young girls who ride with them as providing status for both the girls and drivers, and there seemed to be recognition of the transactional nature of the relationship between taxi drivers and taxi queens. The stigmatisation of young girls who ride with taxi drivers was evident. Drivers had knowledge and awareness of the risks of unsafe sex and supported condom use, although there appeared to be some uncertainty and confusion about the likelihood of HIV infection between drivers and girls. While taxi drivers recognised the role of alcohol in relationships with young girls, they seemed to deny that the abuse of drugs was common. The study highlights a number of key areas that need to be explored with men in the taxi industry, in order to address risk behaviours for both taxi drivers and the girls who ride with them.

  3. Modeling taxi demand with GPS data from taxis and transit.

    DOT National Transportation Integrated Search

    2014-07-01

    Identifying factors that influence taxi demand is very important for understanding where and when people use taxis and how taxi demand relates to the availability and quality of transit service. This study used a large set of global positioning syste...

  4. Understanding taxi travel patterns

    NASA Astrophysics Data System (ADS)

    Cai, Hua; Zhan, Xiaowei; Zhu, Ji; Jia, Xiaoping; Chiu, Anthony S. F.; Xu, Ming

    2016-09-01

    Taxis play important roles in modern urban transportation systems, especially in mega cities. While providing necessary amenities, taxis also significantly contribute to traffic congestion, urban energy consumption, and air pollution. Understanding the travel patterns of taxis is thus important for addressing many urban sustainability challenges. Previous research has primarily focused on examining the statistical properties of passenger trips, which include only taxi trips occupied with passengers. However, unoccupied trips are also important for urban sustainability issues because they represent potential opportunities to improve the efficiency of the transportation system. Therefore, we need to understand the travel patterns of taxis as an integrated system, instead of focusing only on the occupied trips. In this study we examine GPS trajectory data of 11,880 taxis in Beijing, China for a period of three weeks. Our results show that taxi travel patterns share similar traits with travel patterns of individuals but also exhibit differences. Trip displacement distribution of taxi travels is statistically greater than the exponential distribution and smaller than the truncated power-law distribution. The distribution of short trips (less than 30 miles) can be best fitted with power-law while long trips follow exponential decay. We use radius of gyration to characterize individual taxi's travel distance and find that it does not follow a truncated power-law as observed in previous studies. Spatial and temporal regularities exist in taxi travels. However, with increasing spatial coverage, taxi trips can exhibit dual high probability density centers.

  5. Yellow taxis have fewer accidents than blue taxis because yellow is more visible than blue.

    PubMed

    Ho, Teck-Hua; Chong, Juin Kuan; Xia, Xiaoyu

    2017-03-21

    Is there a link between the color of a taxi and how many accidents it has? An analysis of 36 mo of detailed taxi, driver, and accident data (comprising millions of data points) from the largest taxi company in Singapore suggests that there is an explicit link. Yellow taxis had 6.1 fewer accidents per 1,000 taxis per month than blue taxis, a 9% reduction in accident probability. We rule out driver difference as an explanatory variable and empirically show that because yellow taxis are more noticeable than blue taxis-especially when in front of another vehicle, and in street lighting-other drivers can better avoid hitting them, directly reducing the accident rate. This finding can play a significant role when choosing colors for public transportation and may save lives as well as millions of dollars.

  6. Inferring Passenger Denial Behavior of Taxi Drivers from Large-Scale Taxi Traces.

    PubMed

    Zhang, Sihai; Wang, Zhiyang

    2016-01-01

    How to understand individual human actions is a fundamental question to modern science, which drives and incurs many social, technological, racial, religious and economic phenomena. Human dynamics tries to reveal the temporal pattern and internal mechanism of human actions in letter or electronic communications, from the perspective of continuous interactions among friends or acquaintances. For interactions between stranger to stranger, taxi industry provide fruitful phenomina and evidence to investigate the action decisions. In fact, one striking disturbing events commonly reported in taxi industry is passenger refusing or denial, whose reasons vary, including skin color, blind passenger, being a foreigner or too close destination, religion reasons and anti specific nationality, so that complaints about taxi passenger refusing have to be concerned and processed carefully by local governments. But more universal factors for this phenomena are of great significance, which might be fulfilled by big data research to obtain novel insights in this question. In this paper, we demonstrate the big data analytics application in revealing novel insights from massive taxi trace data, which, for the first time, validates the passengers denial in taxi industry and estimates the denial ratio in Beijing city. We first quantify the income differentiation facts among taxi drivers. Then we find out that choosing the drop-off places also contributes to the high income for taxi drivers, compared to the previous explanation of mobility intelligence. Moreover, we propose the pick-up, drop-off and grid diversity concepts and related diversity analysis suggest that, high income taxi drivers will deny passengers in some situations, so as to choose the passengers' destination they prefer. Finally we design an estimation method for denial ratio and infer that high income taxi drivers will deny passengers with 8.52% likelihood in Beijing. Our work exhibits the power of big data analysis in

  7. Inferring Passenger Denial Behavior of Taxi Drivers from Large-Scale Taxi Traces

    PubMed Central

    Zhang, Sihai; Wang, Zhiyang

    2016-01-01

    How to understand individual human actions is a fundamental question to modern science, which drives and incurs many social, technological, racial, religious and economic phenomena. Human dynamics tries to reveal the temporal pattern and internal mechanism of human actions in letter or electronic communications, from the perspective of continuous interactions among friends or acquaintances. For interactions between stranger to stranger, taxi industry provide fruitful phenomina and evidence to investigate the action decisions. In fact, one striking disturbing events commonly reported in taxi industry is passenger refusing or denial, whose reasons vary, including skin color, blind passenger, being a foreigner or too close destination, religion reasons and anti specific nationality, so that complaints about taxi passenger refusing have to be concerned and processed carefully by local governments. But more universal factors for this phenomena are of great significance, which might be fulfilled by big data research to obtain novel insights in this question. In this paper, we demonstrate the big data analytics application in revealing novel insights from massive taxi trace data, which, for the first time, validates the passengers denial in taxi industry and estimates the denial ratio in Beijing city. We first quantify the income differentiation facts among taxi drivers. Then we find out that choosing the drop-off places also contributes to the high income for taxi drivers, compared to the previous explanation of mobility intelligence. Moreover, we propose the pick-up, drop-off and grid diversity concepts and related diversity analysis suggest that, high income taxi drivers will deny passengers in some situations, so as to choose the passengers’ destination they prefer. Finally we design an estimation method for denial ratio and infer that high income taxi drivers will deny passengers with 8.52% likelihood in Beijing. Our work exhibits the power of big data analysis in

  8. Yellow taxis have fewer accidents than blue taxis because yellow is more visible than blue

    PubMed Central

    Ho, Teck-Hua; Chong, Juin Kuan; Xia, Xiaoyu

    2017-01-01

    Is there a link between the color of a taxi and how many accidents it has? An analysis of 36 mo of detailed taxi, driver, and accident data (comprising millions of data points) from the largest taxi company in Singapore suggests that there is an explicit link. Yellow taxis had 6.1 fewer accidents per 1,000 taxis per month than blue taxis, a 9% reduction in accident probability. We rule out driver difference as an explanatory variable and empirically show that because yellow taxis are more noticeable than blue taxis—especially when in front of another vehicle, and in street lighting—other drivers can better avoid hitting them, directly reducing the accident rate. This finding can play a significant role when choosing colors for public transportation and may save lives as well as millions of dollars. PMID:28265081

  9. Shared-Ride Taxi System Requirements Study

    DOT National Transportation Integrated Search

    1979-05-01

    Shared-ride taxi (SRT) is different from the exclusive-ride taxi (ERT) in that the taxi may be shared by unrelated passengers with different origins/destinations. By simultaneously serving more than one passenger, SRT may improve vehicle productivity...

  10. TaxiCom 95: International Survey of Leading Innovational Taxi Communications and Operations Approaches

    DOT National Transportation Integrated Search

    1995-08-01

    TaxiCom '95 is an update and extension of "Taxi-Based Paratransit : Technology/Operation Packages in Europe," a technical survey prepared by : EcoPlan in 1985 and distributed by the U.S. Department of : Transportation/Federal Transit Administration's...

  11. Modeling level of urban taxi services using neural network

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xu, J.; Wong, S.C.; Tong, C.O.

    1999-05-01

    This paper is concerned with the modeling of the complex demand-supply relationship in urban taxi services. A neural network model is developed, based on a taxi service situation observed in the urban area of Hong Kong. The input consists of several exogenous variables including number of licensed taxis, incremental charge of taxi fare, average occupied taxi journey time, average disposable income, and population and customer price index; the output consists of a set of endogenous variables including daily taxi passenger demand, passenger waiting time, vacant taxi headway, average percentage of occupied taxis, taxi utilization, and average taxi waiting time. Comparisonsmore » of the estimation accuracy are made between the neural network model and the simultaneous equations model. The results show that the neural network-based macro taxi model can obtain much more accurate information of the taxi services than the simultaneous equations model does. Although the data set used for training the neural network is small, the results obtained thus far are very encouraging. The neural network model can be used as a policy tool by regulator to assist with the decisions concerning the restriction over the number of taxi licenses and the fixing of the taxi fare structure as well as a range of service quality control.« less

  12. The application of algorithm in taxi security system

    NASA Astrophysics Data System (ADS)

    Luo, Chengyu

    2017-08-01

    With the booming of the society and economy today, Taxis and private cars have gradually become one of the most popular tools in transportation for their low price and convenience. However, because of the breakdown in the security system, a few accidents occurred due to the illegal taxi. The unreliable security management has attributed to the lack of trust in taxi companies and relevant regulatory authorities, which considered to be the reason why people are worried about it. Accordingly, we put forward a design for a taxi security system, making use of modern technology such as NFC, iBeacon, GPS combined with algorithms, automatically recognize the taxi we take, and reflecting basic information of taxi and driver on our mobile phone.

  13. Health assessment of taxi drivers in the city of Tshwane.

    PubMed

    Ramukumba, Tendani S; Mathikhi, Makwena S

    2016-11-30

    Taxi driving seems to be a strenuous occupation. There was evidence-based paucity of literature on health assessment of taxi drivers. Meanwhile taxi drivers of South Africa were burdened by communicable and non-communicable diseases including high-level exposure to injuries and criminal attacks. Health assessment of this cohort group enables mitigation to engage in appropriation of relevant interventions related to the occupational needs of taxi drivers. The objective of the study was to conduct health assessment of taxi drivers in the city of Tshwane to identify health risk factors. An exploratory, descriptive and quantitative survey was conducted and anthropometric measurements of blood pressure, body mass index and waist circumference were monitored and recorded on a convenience sample of 69 taxi drivers in Tshwane Municipality. Consent was sought from individual taxi drivers who participated in the study, while taxi rank queue marshals assisted with smooth running of the process. Data were gathered using a questionnaire. Data analysis was performed using statistical STATA II with the assistance of a statistician. The study found that taxi drivers were obese, hypertensive, had type II diabetes-related risk factors, including unhealthy life style practices. The results indicate that the general health of taxi drivers impacts their occupation. The findings implicate that the health status of taxi operators in Tshwane was a serious concern and urgent concerted effort is needed to engage in lifestyle modification of taxi drivers. The need for health promotion and formalised occupational health services was recommended.

  14. Energy Taxis Is the Dominant Behavior in Azospirillum brasilense

    PubMed Central

    Alexandre, Gladys; Greer, Suzanne E.; Zhulin, Igor B.

    2000-01-01

    Energy taxis encompasses aerotaxis, phototaxis, redox taxis, taxis to alternative electron acceptors, and chemotaxis to oxidizable substrates. The signal for this type of behavior is originated within the electron transport system. Energy taxis was demonstrated, as a part of an overall behavior, in several microbial species, but it did not appear as the dominant determinant in any of them. In this study, we show that most behavioral responses proceed through this mechanism in the alpha-proteobacterium Azospirillum brasilense. First, chemotaxis to most chemoeffectors typical of the azospirilla habitat was found to be metabolism dependent and required a functional electron transport system. Second, other energy-related responses, such as aerotaxis, redox taxis, and taxis to alternative electron acceptors, were found in A. brasilense. Finally, a mutant lacking a cytochrome c oxidase of the cbb3 type was affected in chemotaxis, redox taxis, and aerotaxis. Altogether, the results indicate that behavioral responses to most stimuli in A. brasilense are triggered by changes in the electron transport system. PMID:11029423

  15. Taxi Cab Syndrome: A Review of the Extensive Genitourinary Pathology Experienced by Taxi Cab Drivers and What We Can Do to Help

    PubMed Central

    Mass, Alon Y; Goldfarb, David S; Shah, Ojas

    2014-01-01

    This review consolidates knowledge regarding the extensive genitourinary pathology experienced by taxi cab drivers. Taxi cab, livery, truck, and other drivers all objectively and subjectively may have more voiding dysfunction, infertility, urolithiasis, bladder cancer, and urinary infections as compared with nonprofessional drivers; this is called taxi cab syndrome. Together with governmental and medical assistance, simple interventions—such as education, the addition of taxi relief stations, and possibly the use of sanitary urinary collection devices—to curb the progression of genitourinary disease in taxi drivers should be prospectively studied. It is postulated that many of these interventions may also benefit other groups of occupationally related infrequent voiders. PMID:25337038

  16. 14 CFR 23.1383 - Taxi and landing lights.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Taxi and landing lights. 23.1383 Section 23... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Lights § 23.1383 Taxi and landing lights. Each taxi and landing light must be designed and installed so that: (a) No...

  17. 14 CFR 23.1383 - Taxi and landing lights.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Taxi and landing lights. 23.1383 Section 23... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Lights § 23.1383 Taxi and landing lights. Each taxi and landing light must be designed and installed so that: (a) No...

  18. 14 CFR 23.1383 - Taxi and landing lights.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Taxi and landing lights. 23.1383 Section 23... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Lights § 23.1383 Taxi and landing lights. Each taxi and landing light must be designed and installed so that: (a) No...

  19. 14 CFR 23.1383 - Taxi and landing lights.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Taxi and landing lights. 23.1383 Section 23... AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Equipment Lights § 23.1383 Taxi and landing lights. Each taxi and landing light must be designed and installed so that: (a) No...

  20. The impact of rainfall on the temporal and spatial distribution of taxi passengers

    PubMed Central

    Zhang, Yong; Gao, Liangpeng; Geng, Nana; Li, Xuefeng

    2017-01-01

    This paper focuses on the impact of rainfall on the temporal and spatial distribution of taxi passengers. The main objective is to provide guidance for taxi scheduling on rainy days. To this end, we take the occupied and empty states of taxis as units of analysis. By matching a taxi's GPS data to its taximeter data, we can obtain the taxi's operational time and the taxi driver's income from every unit of analysis. The ratio of taxi operation time to taxi drivers' income is used to measure the quality of taxi passengers. The research results show that the spatio-temporal evolution of urban taxi service demand differs based on rainfall conditions and hours of operation. During non-rush hours, taxi demand in peripheral areas is significantly reduced under increasing precipitation conditions, whereas during rush hours, the demand for highly profitable taxi services steadily increases. Thus, as an intelligent response for taxi operations and dispatching, taxi services should guide cruising taxis to high-demand regions to increase their service time and ride opportunities. PMID:28873430

  1. 49 CFR 37.29 - Private entities providing taxi service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Private entities providing taxi service. 37.29... INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.29 Private entities providing taxi service. (a) Providers of taxi service are subject to the requirements of this part for private entities primarily...

  2. 49 CFR 37.29 - Private entities providing taxi service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Private entities providing taxi service. 37.29... INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.29 Private entities providing taxi service. (a) Providers of taxi service are subject to the requirements of this part for private entities primarily...

  3. Standardization of databases for AMDB taxi routing functions

    NASA Astrophysics Data System (ADS)

    Pschierer, C.; Sindlinger, A.; Schiefele, J.

    2010-04-01

    Input, management, and display of taxi routes on airport moving map displays (AMM) have been covered in various studies in the past. The demonstrated applications are typically based on Aerodrome Mapping Databases (AMDB). Taxi routing functions require specific enhancements, typically in the form of a graph network with nodes and edges modeling all connectivities within an airport, which are not supported by the current AMDB standards. Therefore, the data schemas and data content have been defined specifically for the purpose and test scenarios of these studies. A standardization of the data format for taxi routing information is a prerequisite for turning taxi routing functions into production. The joint RTCA/EUROCAE special committee SC-217, responsible for updating and enhancing the AMDB standards DO-272 [1] and DO-291 [2], is currently in the process of studying different alternatives and defining reasonable formats. Requirements for taxi routing data are primarily driven by depiction concepts for assigned and cleared taxi routes, but also by database size and the economic feasibility. Studied concepts are similar to the ones described in the GDF (geographic data files) specification [3], which is used in most car navigation systems today. They include - A highly aggregated graph network of complex features - A modestly aggregated graph network of simple features - A non-explicit topology of plain AMDB taxi guidance line elements This paper introduces the different concepts and their advantages and disadvantages.

  4. 14 CFR 294.3 - General requirements for Canadian charter air taxi operators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... air taxi operators. 294.3 Section 294.3 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General § 294.3 General requirements for Canadian charter air taxi operators. A Canadian charter air taxi operator shall...

  5. 14 CFR 294.3 - General requirements for Canadian charter air taxi operators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... air taxi operators. 294.3 Section 294.3 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General § 294.3 General requirements for Canadian charter air taxi operators. A Canadian charter air taxi operator shall...

  6. A Study Examining Compliance with the Anti-Tobacco Law Nb. 4207 Inside Taxis

    PubMed Central

    Öztürk, Burcu; Kosku, Hakan; Güven, İbrahim; Erdoğan, Beyza; Sarıtaş, Özge; Şanver, Tuğçe; Aslan, Dilek

    2017-01-01

    OBJECTIVES This observational study assessed compliance with the anti-tobacco Law Nb 4207 with regard to taxis in Çankaya district, Ankara. MATERIAL AND METHODS This descriptive study was conducted in Kızılay, Kuğulu, and Tandoğan intersections on January 18–23, 2016 between 9.00–11.00 and 14.00–16.00 hours in Ankara. Data regarding the status of the taxi (either cruising or not), smoking inside taxis, smoking status of the taxi drivers and/or clients, location of the clients in the taxi, presence of a child in the taxi, and status of the windows (open or not) were recorded using a data-gathering form. RESULTS Three thousand six hundred fifty-six taxis were evaluated, of which 79 (2.2%) taxi drivers were observed smoking. Clients were observed smoking in 17 taxis (1.3%). Ninety-four taxi drivers and/or clients (2.6%) were observed smoking. Taxi drivers smoked more frequently in the absence of a client. In addition, a smoking client influenced the taxi driver’s smoking status (p<0.001). CONCLUSION Violation of the anti-tobacco Law Nb 4207 was observed. In this regard, the number of inspections needs to be increased. Systematic training programs for the taxi drivers regarding the risks of tobacco should be a priority. Preventive studies concerning the hazards of passive smoking should be also conducted at a community level. PMID:29404168

  7. Analyzing Impact Factors of Airport Taxiing Delay Based on Ads-B Data

    NASA Astrophysics Data System (ADS)

    Li, J.; Wang, X.; Xu, Y.; Li, Q.; He, C.; Li, Y.

    2017-09-01

    Identifying the factors that cause taxiing delay on airports is a prerequisite for optimizing aircraft taxiing schemes, and helps improve the efficiency of taxiing system. Few of current studies had quantified the potential influencing factors and further investigated their intrinsic relationship. In view of these problems, this paper uses ADS-B data to calculate taxiing delay time by restoring taxiing route and identifying key status points, and further analyzes the impact factors of airport taxiing delay by investigating the relationship between delay time and environmental data such as weather, wind, visibility etc. The case study in Guangzhou Baiyun Airport validates the effectiveness of the proposed method.

  8. Taxi-cabs as Subjects for a Population Study

    ERIC Educational Resources Information Center

    Bishop, J. A.; Bradley, J. S.

    1972-01-01

    Describes the use of capture-recapture techniques to estimate the population of taxis in Liverpool and demonstrates the points of similarity to animal population estimation. Considers advantages of studying taxis rather than organisms in introductory studies of the techniques. (AL)

  9. a Web-Based Platform for Visualizing Spatiotemporal Dynamics of Big Taxi Data

    NASA Astrophysics Data System (ADS)

    Xiong, H.; Chen, L.; Gui, Z.

    2017-09-01

    With more and more vehicles equipped with Global Positioning System (GPS), access to large-scale taxi trajectory data has become increasingly easy. Taxis are valuable sensors and information associated with taxi trajectory can provide unprecedented insight into many aspects of city life. But analysing these data presents many challenges. Visualization of taxi data is an efficient way to represent its distributions and structures and reveal hidden patterns in the data. However, Most of the existing visualization systems have some shortcomings. On the one hand, the passenger loading status and speed information cannot be expressed. On the other hand, mono-visualization form limits the information presentation. In view of these problems, this paper designs and implements a visualization system in which we use colour and shape to indicate passenger loading status and speed information and integrate various forms of taxi visualization. The main work as follows: 1. Pre-processing and storing the taxi data into MongoDB database. 2. Visualization of hotspots for taxi pickup points. Through DBSCAN clustering algorithm, we cluster the extracted taxi passenger's pickup locations to produce passenger hotspots. 3. Visualizing the dynamic of taxi moving trajectory using interactive animation. We use a thinning algorithm to reduce the amount of data and design a preloading strategyto load the data smoothly. Colour and shape are used to visualize the taxi trajectory data.

  10. System dynamics model of taxi management in metropolises: Economic and environmental implications for Beijing.

    PubMed

    Wang, Hao; Zhang, Kai; Chen, Junhua; Wang, Zhifeng; Li, Guijun; Yang, Yuqi

    2018-05-01

    Taxis are an important component of urban passenger transport. Research on the daily dispatching of taxis and the utility of governmental management is important for the improvement of passenger travel, taxi driver income and environmental impacts. However, urban taxi management is a complex and dynamic system that is affected by many factors, and positive/negative feedback relationships and nonlinear interactions exist between each subsystem and variable. Therefore, conventional research methods can hardly depict its characteristics comprehensively. To bridge this gap, this paper develops a system dynamics model of urban taxi management, in which the empty-loaded rate and total demand are selected as key factors affecting taxi dispatching, and the impacts of taxi fares on driver income and travel demand are taken into account. After the validation of the model, taxi operations data derived from a prior analysis of origin-destination data of Beijing taxis are used as input for the model to simulate the taxi market in Beijing. Finally, economic and environmental implications are provided for the government to optimise policies on taxi management. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Pilot age and error in air taxi crashes.

    PubMed

    Rebok, George W; Qiang, Yandong; Baker, Susan P; Li, Guohua

    2009-07-01

    The associations of pilot error with the type of flight operations and basic weather conditions are well documented. The correlation between pilot characteristics and error is less clear. This study aims to examine whether pilot age is associated with the prevalence and patterns of pilot error in air taxi crashes. Investigation reports from the National Transportation Safety Board for crashes involving non-scheduled Part 135 operations (i.e., air taxis) in the United States between 1983 and 2002 were reviewed to identify pilot error and other contributing factors. Crash circumstances and the presence and type of pilot error were analyzed in relation to pilot age using Chi-square tests. Of the 1751 air taxi crashes studied, 28% resulted from mechanical failure, 25% from loss of control at landing or takeoff, 7% from visual flight rule conditions into instrument meteorological conditions, 7% from fuel starvation, 5% from taxiing, and 28% from other causes. Crashes among older pilots were more likely to occur during the daytime rather than at night and off airport than on airport. The patterns of pilot error in air taxi crashes were similar across age groups. Of the errors identified, 27% were flawed decisions, 26% were inattentiveness, 23% mishandled aircraft kinetics, 15% mishandled wind and/or runway conditions, and 11% were others. Pilot age is associated with crash circumstances but not with the prevalence and patterns of pilot error in air taxi crashes. Lack of age-related differences in pilot error may be attributable to the "safe worker effect."

  12. Pilot Age and Error in Air-Taxi Crashes

    PubMed Central

    Rebok, George W.; Qiang, Yandong; Baker, Susan P.; Li, Guohua

    2010-01-01

    Introduction The associations of pilot error with the type of flight operations and basic weather conditions are well documented. The correlation between pilot characteristics and error is less clear. This study aims to examine whether pilot age is associated with the prevalence and patterns of pilot error in air-taxi crashes. Methods Investigation reports from the National Transportation Safety Board for crashes involving non-scheduled Part 135 operations (i.e., air taxis) in the United States between 1983 and 2002 were reviewed to identify pilot error and other contributing factors. Crash circumstances and the presence and type of pilot error were analyzed in relation to pilot age using Chi-square tests. Results Of the 1751 air-taxi crashes studied, 28% resulted from mechanical failure, 25% from loss of control at landing or takeoff, 7% from visual flight rule conditions into instrument meteorological conditions, 7% from fuel starvation, 5% from taxiing, and 28% from other causes. Crashes among older pilots were more likely to occur during the daytime rather than at night and off airport than on airport. The patterns of pilot error in air-taxi crashes were similar across age groups. Of the errors identified, 27% were flawed decisions, 26% were inattentiveness, 23% mishandled aircraft kinetics, 15% mishandled wind and/or runway conditions, and 11% were others. Conclusions Pilot age is associated with crash circumstances but not with the prevalence and patterns of pilot error in air-taxi crashes. Lack of age-related differences in pilot error may be attributable to the “safe worker effect.” PMID:19601508

  13. 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 commuter...

  14. 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 commuter...

  15. 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 commuter...

  16. 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 commuter...

  17. 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 commuter...

  18. Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization

    PubMed Central

    Niu, Liyong; Zhang, Di

    2015-01-01

    Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly. PMID:26236770

  19. Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization.

    PubMed

    Niu, Liyong; Zhang, Di

    2015-01-01

    Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly.

  20. Seatbelt use amongst taxi drivers in Beijing, China.

    PubMed

    Passmore, J; Ozanne-Smith, J

    2006-09-01

    Associated with explosive growth in motorization, China has the world's highest road toll with more than 100,000 deaths and 400,000 injuries annually. In response, the Chinese Government introduced the first road traffic safety law in 2003, which included mandatory use of seatbelts by drivers and front seat passengers. Noting frequent non-compliance to this seatbelt regulation by Beijing taxi drivers, the authors studied seatbelt use patterns as onboard observers in a convenience sample of 235 taxi trips. Findings indicated a low seatbelt-wearing rate among taxi drivers of 7.7%, an overt non-wearing rate of 57%, covert non-wearing of 35.3% and total non-compliance of 92.3%. As in high-income countries, adoption of proven safety strategies, including wearing safety restraints, could contribute to reducing the Chinese road toll, particularly as vehicle occupant numbers and the availability of restraints increases. Further investigation of reasons for non-compliance and pretense of wearing seatbelts is required to inform future seatbelt-wearing promotions, including attitudinal studies of taxi drivers. Seatbelt wearing rates should continue to be monitored.

  1. Comparing taxi clearance input layouts for advancements in flight deck automation for surface operations

    NASA Astrophysics Data System (ADS)

    Cheng, Lara W. S.

    Airport moving maps (AMMs) have been shown to decrease navigation errors, increase taxiing speed, and reduce workload when they depict airport layout, current aircraft position, and the cleared taxi route. However, current technologies are limited in their ability to depict the cleared taxi route due to the unavailability of datacomm or other means of electronically transmitting clearances from ATC to the flight deck. This study examined methods by which pilots can input ATC-issued taxi clearances to support taxi route depictions on the AMM. Sixteen general aviation (GA) pilots used a touchscreen monitor to input taxi clearances using two input layouts, softkeys and QWERTY, each with and without feedforward (graying out invalid inputs). QWERTY yielded more taxi route input errors than the softkeys layout. The presence of feedforward did not produce fewer taxi route input errors than in the non-feedforward condition. The QWERTY layout did reduce taxi clearance input times relative to the softkeys layout, but when feedforward was present this effect was observed only for the longer, 6-segment taxi clearances. It was observed that with the softkeys layout, feedforward reduced input times compared to non-feedforward but only for the 4-segment clearances. Feedforward did not support faster taxi clearance input times for the QWERTY layout. Based on the results and analyses of the present study, it is concluded that for taxi clearance inputs, (1) QWERTY remain the standard for alphanumeric inputs, and (2) feedforward be investigated further, with a focus on participant preference and performance of black-gray contrast of keys.

  2. Effects of Taxi Regulatory Revision in San Diego, California

    DOT National Transportation Integrated Search

    1983-05-01

    Effective January 1979 the City of San Diego removed its previous ceiling on taxi licenses and began issuing 6 new taxi permits every month; in July, this limit was raised to 15. In August, the city replaced the standard rate of fare with a variable ...

  3. Uncovering urban human mobility from large scale taxi GPS data

    NASA Astrophysics Data System (ADS)

    Tang, Jinjun; Liu, Fang; Wang, Yinhai; Wang, Hua

    2015-11-01

    Taxi GPS trajectories data contain massive spatial and temporal information of urban human activity and mobility. Taking taxi as mobile sensors, the information derived from taxi trips benefits the city and transportation planning. The original data used in study are collected from more than 1100 taxi drivers in Harbin city. We firstly divide the city area into 400 different transportation districts and analyze the origin and destination distribution in urban area on weekday and weekend. The Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm is used to cluster pick-up and drop-off locations. Furthermore, four spatial interaction models are calibrated and compared based on trajectories in shopping center of Harbin city to study the pick-up location searching behavior. By extracting taxi trips from GPS data, travel distance, time and average speed in occupied and non-occupied status are then used to investigate human mobility. Finally, we use observed OD matrix of center area in Harbin city to model the traffic distribution patterns based on entropy-maximizing method, and the estimation performance verify its effectiveness in case study.

  4. A Mixed Integer Linear Program for Solving a Multiple Route Taxi Scheduling Problem

    NASA Technical Reports Server (NTRS)

    Montoya, Justin Vincent; Wood, Zachary Paul; Rathinam, Sivakumar; Malik, Waqar Ahmad

    2010-01-01

    Aircraft movements on taxiways at busy airports often create bottlenecks. This paper introduces a mixed integer linear program to solve a Multiple Route Aircraft Taxi Scheduling Problem. The outputs of the model are in the form of optimal taxi schedules, which include routing decisions for taxiing aircraft. The model extends an existing single route formulation to include routing decisions. An efficient comparison framework compares the multi-route formulation and the single route formulation. The multi-route model is exercised for east side airport surface traffic at Dallas/Fort Worth International Airport to determine if any arrival taxi time savings can be achieved by allowing arrivals to have two taxi routes: a route that crosses an active departure runway and a perimeter route that avoids the crossing. Results indicate that the multi-route formulation yields reduced arrival taxi times over the single route formulation only when a perimeter taxiway is used. In conditions where the departure aircraft are given an optimal and fixed takeoff sequence, accumulative arrival taxi time savings in the multi-route formulation can be as high as 3.6 hours more than the single route formulation. If the departure sequence is not optimal, the multi-route formulation results in less taxi time savings made over the single route formulation, but the average arrival taxi time is significantly decreased.

  5. Measuring and modeling air exchange rates inside taxi cabs in Los Angeles, California

    NASA Astrophysics Data System (ADS)

    Shu, Shi; Yu, Nu; Wang, Yueyan; Zhu, Yifang

    2015-12-01

    Air exchange rates (AERs) have a direct impact on traffic-related air pollutant (TRAP) levels inside vehicles. Taxi drivers are occupationally exposed to TRAP on a daily basis, yet there is limited measurement of AERs in taxi cabs. To fill this gap, AERs were quantified in 22 representative Los Angeles taxi cabs including 10 Prius, 5 Crown Victoria, 3 Camry, 3 Caravan, and 1 Uplander under realistic driving (RD) conditions. To further study the impacts of window position and ventilation settings on taxi AERs, additional tests were conducted on 14 taxis with windows closed (WC) and on the other 8 taxis with not only windows closed but also medium fan speed (WC-MFS) under outdoor air mode. Under RD conditions, the AERs in all 22 cabs had a mean of 63 h-1 with a median of 38 h-1. Similar AERs were observed under WC condition when compared to those measured under RD condition. Under WC-MFS condition, AERs were significantly increased in all taxi cabs, when compared with those measured under RD condition. A General Estimating Equation (GEE) model was developed and the modeling results showed that vehicle model was a significant factor in determining the AERs in taxi cabs under RD condition. Driving speed and car age were positively associated with AERs but not statistically significant. Overall, AERs measured in taxi cabs were much higher than typical AERs people usually encounter in indoor environments such as homes, offices, and even regular passenger vehicles.

  6. Mining spatiotemporal patterns of urban dwellers from taxi trajectory data

    NASA Astrophysics Data System (ADS)

    Mao, Feng; Ji, Minhe; Liu, Ting

    2016-06-01

    With the widespread adoption of locationaware technology, obtaining long-sequence, massive and high-accuracy spatiotemporal trajectory data of individuals has become increasingly popular in various geographic studies. Trajectory data of taxis, one of the most widely used inner-city travel modes, contain rich information about both road network traffic and travel behavior of passengers. Such data can be used to study the microscopic activity patterns of individuals as well as the macro system of urban spatial structures. This paper focuses on trajectories obtained from GPS-enabled taxis and their applications for mining urban commuting patterns. A novel approach is proposed to discover spatiotemporal patterns of household travel from the taxi trajectory dataset with a large number of point locations. The approach involves three critical steps: spatial clustering of taxi origin-destination (OD) based on urban traffic grids to discover potentially meaningful places, identifying threshold values from statistics of the OD clusters to extract urban jobs-housing structures, and visualization of analytic results to understand the spatial distribution and temporal trends of the revealed urban structures and implied household commuting behavior. A case study with a taxi trajectory dataset in Shanghai, China is presented to demonstrate and evaluate the proposed method.

  7. Taxi, Jitneys and Poverty

    ERIC Educational Resources Information Center

    Rosenbloom, Sandi

    1970-01-01

    Version of the paper given at The Transportation and Poverty Conference of the American Academy of Arts and Sciences. Argues for revival of jitneys (12-14 capacity motor vehicles, operating on fixed routes, fares zone-rated) to serve ghetto residents and provide employment, too. Taxi company competition also discussed. (KG)

  8. Taxi-Out Time Prediction for Departures at Charlotte Airport Using Machine Learning Techniques

    NASA Technical Reports Server (NTRS)

    Lee, Hanbong; Malik, Waqar; Jung, Yoon C.

    2016-01-01

    Predicting the taxi-out times of departures accurately is important for improving airport efficiency and takeoff time predictability. In this paper, we attempt to apply machine learning techniques to actual traffic data at Charlotte Douglas International Airport for taxi-out time prediction. To find the key factors affecting aircraft taxi times, surface surveillance data is first analyzed. From this data analysis, several variables, including terminal concourse, spot, runway, departure fix and weight class, are selected for taxi time prediction. Then, various machine learning methods such as linear regression, support vector machines, k-nearest neighbors, random forest, and neural networks model are applied to actual flight data. Different traffic flow and weather conditions at Charlotte airport are also taken into account for more accurate prediction. The taxi-out time prediction results show that linear regression and random forest techniques can provide the most accurate prediction in terms of root-mean-square errors. We also discuss the operational complexity and uncertainties that make it difficult to predict the taxi times accurately.

  9. Autonomous vehicles are cost-effective when used as taxis.

    PubMed

    Freedman, Isaac G; Kim, Ellen; Muennig, Peter A

    2018-06-04

    Autonomous vehicles (AVs) will radically re-shape the health and well-being of people in the United States in good ways and bad. We set out to estimate a reasonable time-to-adoption using cost-effectivenessmodels to estimate the point at which AVs become reasonably safe and affordable for widespread adoption. We used Waymo data (previously, Google Self-Driving Car Project) and a microsimulation model to explore projected costs and safety issues today and five years from today to get a sense of the speed of consumer adoption were AVs brought to the market. The adoption of AVs for private use was associated with an ICER of 1,396,110/QALY gained today, a figure that would decline to 173,890/QALY gained 5-years in the future. However, AV taxis are both less expensive and potentially already safer than human-piloted taxis. While AVs are not unlikely to be used a family vehicles any time soon, it would make economic sense to adopt them as taxis today. Legislation enhancing the benefits while mitigating the potential harmful health impacts of AV taxis is needed with some urgency.

  10. Assessing and reducing fine and ultrafine particles inside Los Angeles taxis

    NASA Astrophysics Data System (ADS)

    Yu, Nu; Shu, Shi; Lin, Yan; Zhu, Yifang

    2018-05-01

    Taxi drivers and passengers are exposed to high levels of traffic-related air pollutants, but their exposures to fine (PM2.5) and ultrafine particles (UFPs) and related mitigation strategies are rarely explored. In this study, UFP and PM2.5 concentrations were monitored concurrently inside and outside of 22 taxis under different ventilation and mitigation conditions. Under realistic working conditions (no mitigation; NM), the average UFP and PM2.5 levels inside taxis were 1.46 × 104 particles/cm3 and 26 μg/m3, respectively. When the taxi ventilation was set to outside air mode and the windows kept closed, in-cabin UFP and PM2.5 concentrations are significantly associated with on-road concentrations, driving speed, and cabin air filter usage. The average in-cabin to on-roadway (I/O) ratios for UFP and PM2.5 were reduced from 0.60 to 0.75 under NM, to 0.47 and 0.52 under the most stringent mitigation strategy of keeping the windows closed and operating a high efficiency cabin air filter (WC + HECA). Among all tested taxi models, Toyota Prius exhibited the lowest UFP and PM2.5 I/O ratios under WC + HECA. Switching cabin air filters from the originally equipped manufacturer filter (OEM) to a HECA filter reduced the UFP and PM2.5 I/O ratios most effectively in Toyota Prius taxis as well.

  11. DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data.

    PubMed

    Putri, Fadhilah Kurnia; Song, Giltae; Kwon, Joonho; Rao, Praveen

    2017-09-25

    One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query ( DISPAQ ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation's Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data.

  12. Airport Shared-Ride Taxi Programs in New York, Chicago and Boston

    DOT National Transportation Integrated Search

    1987-12-01

    This report summarizes the development and operation of three shared-ride taxi operations at major U.S. airports. These are: New York's LaGuardia Airport Share-A-Cab; Super Saver Taxi in Chicago; and Share-A-Cab service at Boston's Logan Airport. The...

  13. Hematocrit levels as cardiovascular risk among taxi drivers in Bangkok, Thailand

    PubMed Central

    ISHIMARU, Tomohiro; ARPHORN, Sara; JIRAPONGSUWAN, Ann

    2016-01-01

    In Thailand, taxi drivers employed in the informal sector often experience hazardous working conditions. Previous studies revealed that elevated Hematocrit (HCT) is a predictor of cardiovascular disease (CVD) risk. This study assessed factors associated with HCT in taxi drivers to predict their occupational CVD risk factors. A cross-sectional study was conducted on 298 male taxi drivers who joined a health check-up campaign in Bangkok, Thailand. HCT and body mass index were retrieved from participant health check-up files. Self-administered questionnaires assessed demographics, driving mileage, working hours, and lifestyle. Statistical associations were analyzed using stepwise linear regression. Our results showed that obesity (p=0.007), daily alcohol drinking (p=0.003), and current or past smoking (p=0.016) were associated with higher HCT levels. While working hours were not directly associated with HCT levels in the current study, the effect on overworking is statistically arguable because most participants worked substantially longer hours. Our findings suggest that taxi drivers’ CVD risk may be increased by their unhealthy work styles. Initiatives to improve general working conditions for taxi drivers should take into account health promotion and CVD prevention. The policy of providing periodic health check-ups is important to make workers in the informal sector aware of their health status. PMID:27151439

  14. Hematocrit levels as cardiovascular risk among taxi drivers in Bangkok, Thailand.

    PubMed

    Ishimaru, Tomohiro; Arphorn, Sara; Jirapongsuwan, Ann

    2016-10-08

    In Thailand, taxi drivers employed in the informal sector often experience hazardous working conditions. Previous studies revealed that elevated Hematocrit (HCT) is a predictor of cardiovascular disease (CVD) risk. This study assessed factors associated with HCT in taxi drivers to predict their occupational CVD risk factors. A cross-sectional study was conducted on 298 male taxi drivers who joined a health check-up campaign in Bangkok, Thailand. HCT and body mass index were retrieved from participant health check-up files. Self-administered questionnaires assessed demographics, driving mileage, working hours, and lifestyle. Statistical associations were analyzed using stepwise linear regression. Our results showed that obesity (p=0.007), daily alcohol drinking (p=0.003), and current or past smoking (p=0.016) were associated with higher HCT levels. While working hours were not directly associated with HCT levels in the current study, the effect on overworking is statistically arguable because most participants worked substantially longer hours. Our findings suggest that taxi drivers' CVD risk may be increased by their unhealthy work styles. Initiatives to improve general working conditions for taxi drivers should take into account health promotion and CVD prevention. The policy of providing periodic health check-ups is important to make workers in the informal sector aware of their health status.

  15. 14 CFR 298.21 - Filing for registration by air taxi operators.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... registration, the aircraft that it is currently operating in its air taxi operations, and the aircraft type, FAA registration number and passenger capacity of each aircraft; (vi) For initial registration, the... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Filing for registration by air taxi...

  16. 14 CFR 298.21 - Filing for registration by air taxi operators.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... registration, the aircraft that it is currently operating in its air taxi operations, and the aircraft type, FAA registration number and passenger capacity of each aircraft; (vi) For initial registration, the... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Filing for registration by air taxi...

  17. 14 CFR 298.21 - Filing for registration by air taxi operators.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... registration, the aircraft that it is currently operating in its air taxi operations, and the aircraft type, FAA registration number and passenger capacity of each aircraft; (vi) For initial registration, the... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Filing for registration by air taxi...

  18. 14 CFR 298.21 - Filing for registration by air taxi operators.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... registration, the aircraft that it is currently operating in its air taxi operations, and the aircraft type, FAA registration number and passenger capacity of each aircraft; (vi) For initial registration, the... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Filing for registration by air taxi...

  19. Considering the effects of ambient particulate matter on the lung function of motorcycle taxi drivers in Bangkok, Thailand.

    PubMed

    Arphorn, Sara; Ishimaru, Tomohiro; Hara, Kunio; Mahasandana, Suwisa

    2018-02-01

    The motorcycle taxi drivers of Bangkok have been heavily exposed to high concentrations of PM 10 (particulate matter with an aerodynamic diameter ≤10 μm), and the impact of this on their lungs has been neither documented nor studied. This study examines the association between exposure to PM 10 and lung function decline among motorcycle taxi drivers. A cross-sectional study was conducted in Bangkok between two groups: a subject group of motorcycle taxi drivers and control group of enclosed vehicle taxi drivers. The findings of the Thailand Pollution Control Department were used to estimate the annual ambient PM 10 concentration levels in the metropolis. Pulmonary functions of motorcycle taxi drivers and enclosed vehicle taxi drivers were measured and compared using the Mann-Whitney test. Multiple linear regression analysis was applied to estimate the effects of PM 10 exposure on the lung function of motorcycle taxi drivers. A total of 1283 motorcycle taxi drivers and 600 taxi drivers were investigated. The mean forced expiratory volume in 1 sec/forced vital capacity (FEV 1 /FVC) of the motorcycle taxi drivers was significantly lower than that of the taxi drivers (P < 0.001). The mean FEV 1 /FVC of motorcycle taxi drivers exposed to ≥50 µg/m 3 PM 10 was statistically lower (-2.82%; 95% confidence interval [CI]: -4.54% to -1.09%) and the mean % vital capacity (%VC) of those exposed to 40-49.9 µg/m 3 PM 10 was statistically lower than that of motorcycle taxi drivers exposed to <30 µg/m 3 PM 10 (-3.33%; 95% CI: -5.79% to -0.87%). Motorcycle taxi drivers were directly exposed to air pollution in their working environment. As a result, their lung function might decrease more than that of enclosed vehicle taxi drivers. With the possible exposure to ≥50 µg/m 3 PM 10 , the vehicular emission standards should be vigorously enforced. Further investigation is warranted to clarify the effect of lung dysfunction on the work and lifestyle of motorcycle taxi

  20. Exposure to particles and nitrogen dioxide among taxi, bus and lorry drivers.

    PubMed

    Lewné, Marie; Nise, Gun; Lind, Marie-Louise; Gustavsson, Per

    2006-03-01

    The aims of this study have been to investigate the occurrence of systematic differences in the personal exposure to motor exhaust between different groups of taxi, bus and lorry drivers, and to study if these are influenced by the choice of exposure indicator. We used one indicator of the gaseous phase, nitrogen dioxide (NO(2)), and one of the particle phase (measured by DataRAM), of the exhausts. A total of 121 drivers were included in the study: 39 taxi drivers, 42 bus drivers and 40 lorry drivers. Personal measurements were performed during one working day. Nitrogen dioxide was measured with passive diffusive samplers and particles with Data-RAM, a logging instrument using nephelometric monitoring. The instrument measures particles between 0.1 and 10 microm in size. The average exposure to NO(2) for lorry drivers was 68 microg/m(3); for bus drivers 60 microg/m(3) and for taxi drivers 48 microg/m(3). For particles the exposure was 57 microg/m(3) for lorry drivers, 44 microg/m(3) for bus drivers and 26 microg/m(3) for taxi drivers. The result remained unchanged when exposures were adjusted for variation in urban background levels of NO(2) and particulate matter with an aerodynamic diameter <10 microm (PM(10)). Lorry drivers experienced the highest exposure and taxi drivers the lowest with bus drivers in an intermediate position, regardless of whether NO(2) or particles were used as exposure indicator. The levels of both NO(2) and particles were higher for bus drivers in the city than for them driving in the suburbs. Using diesel or petrol as a fuel for taxis had no influence on the exposure for the drivers, indicating that the taxi drivers' exposure mainly depends on exhaust from surrounding traffic.

  1. Driving fatigue in professional drivers: a survey of truck and taxi drivers.

    PubMed

    Meng, Fanxing; Li, Shuling; Cao, Lingzhi; Li, Musen; Peng, Qijia; Wang, Chunhui; Zhang, Wei

    2015-01-01

    Fatigue among truck drivers has been studied extensively; however, less is known regarding the fatigue experience of taxi drivers in heavily populated metropolitan areas. This study aimed to compare the differences and similarities between truck and taxi driver fatigue to provide implications for the fatigue management and education of professional drivers. A sample of 274 truck drivers and 286 taxi drivers in Beijing was surveyed via a questionnaire, which included items regarding work characteristics, fatigue experience, accident information, attitude toward fatigue, and methods of counteracting fatigue. Driver fatigue was prevalent among professional drivers, and it was even more serious for taxi drivers. Taxi drivers reported more frequent fatigue experiences and were involved in more accidents. Among the contributing factors to fatigue, prolonged driving time was the most important factor identified by both driver groups. Importantly, the reason for the engagement in prolonged driving was neither due to the lack of awareness concerning the serious outcome of fatigue driving nor because of their poor detection of fatigue. The most probable reason was the optimism bias, as a result of which these professional drivers thought that fatigue was more serious for other drivers than for themselves, and they thought that they were effective in counteracting the effect of fatigue on their driving performance. Moreover, truck drivers tended to employ methods that require stopping to counteract fatigue, whereas taxi drivers preferred methods that were simultaneous with driving. Although both driver groups considered taking a nap as one of the most effective means to address fatigue, this method was not commonly used. Interestingly, these drivers were aware that the methods they frequently used were not the most effective means to counteract fatigue. This study provides knowledge on truck and taxi drivers' characteristics in fatigue experience, fatigue attitude, and

  2. Hybrid Taxis Give Fuel Economy a Lift, Clean Cities, Fleet Experiences, April 2009 (Fact Sheet)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    2009-04-01

    Clean Cities helped Boston, San Antonio, and Cambridge create hybrid taxi programs. The hybrid taxis are able to achieve about twice the gas mileage of a conventional taxi while helping cut gasoline use and fuel costs. Tax credits and other incentives are helping both company owners and drivers make the switch to hybrids. Program leaders have learned some important lessons other cities can benefit from including learning a city's taxi structure, relaying benefits to drivers, and understanding the needs of owners.

  3. DISPAQ: Distributed Profitable-Area Query from Big Taxi Trip Data †

    PubMed Central

    Putri, Fadhilah Kurnia; Song, Giltae; Rao, Praveen

    2017-01-01

    One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query (DISPAQ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation’s Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data. PMID:28946679

  4. Taxi Time Prediction at Charlotte Airport Using Fast-Time Simulation and Machine Learning Techniques

    NASA Technical Reports Server (NTRS)

    Lee, Hanbong

    2016-01-01

    Accurate taxi time prediction is required for enabling efficient runway scheduling that can increase runway throughput and reduce taxi times and fuel consumptions on the airport surface. Currently NASA and American Airlines are jointly developing a decision-support tool called Spot and Runway Departure Advisor (SARDA) that assists airport ramp controllers to make gate pushback decisions and improve the overall efficiency of airport surface traffic. In this presentation, we propose to use Linear Optimized Sequencing (LINOS), a discrete-event fast-time simulation tool, to predict taxi times and provide the estimates to the runway scheduler in real-time airport operations. To assess its prediction accuracy, we also introduce a data-driven analytical method using machine learning techniques. These two taxi time prediction methods are evaluated with actual taxi time data obtained from the SARDA human-in-the-loop (HITL) simulation for Charlotte Douglas International Airport (CLT) using various performance measurement metrics. Based on the taxi time prediction results, we also discuss how the prediction accuracy can be affected by the operational complexity at this airport and how we can improve the fast time simulation model before implementing it with an airport scheduling algorithm in a real-time environment.

  5. Nonconstant Positive Steady States and Pattern Formation of 1D Prey-Taxis Systems

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Song, Yang; Shao, Lingjie

    2017-02-01

    Prey-taxis is the process that predators move preferentially toward patches with highest density of prey. It is well known to have an important role in biological control and the maintenance of biodiversity. To model the coexistence and spatial distributions of predator and prey species, this paper concerns nonconstant positive steady states of a wide class of prey-taxis systems with general functional responses over 1D domain. Linearized stability of the positive equilibrium is analyzed to show that prey-taxis destabilizes prey-predator homogeneity when prey repulsion (e.g., due to volume-filling effect in predator species or group defense in prey species) is present, and prey-taxis stabilizes the homogeneity otherwise. Then, we investigate the existence and stability of nonconstant positive steady states to the system through rigorous bifurcation analysis. Moreover, we provide detailed and thorough calculations to determine properties such as pitchfork and turning direction of the local branches. Our stability results also provide a stable wave mode selection mechanism for thee reaction-advection-diffusion systems including prey-taxis models considered in this paper. Finally, we provide numerical studies of prey-taxis systems with Holling-Tanner kinetics to illustrate and support our theoretical findings. Our numerical simulations demonstrate that the 2× 2 prey-taxis system is able to model the formation and evolution of various striking patterns, such as spikes, periodic oscillations, and coarsening even when the domain is one-dimensional. These dynamics can model the coexistence and spatial distributions of interacting prey and predator species. We also give some insights on how system parameters influence pattern formation in these models.

  6. Driving to Better Health: Cancer and Cardiovascular Risk Assessment among Taxi Cab Operators in Chicago

    PubMed Central

    Apantaku-Onayemi, Funmi; Baldyga, William; Amuwo, Shaffdeen; Adefuye, Adedeji; Mason, Terry; Mitchell, Robin; Blumenthal, Daniel S.

    2014-01-01

    While a number of investigations of the health of taxi cab drivers have been conducted in Europe, Asia, and Africa, virtually none have been conducted in the United States. We undertook a survey of taxi cab operators in the Chicago area to understand better their health status and health promotion practices. The survey was completed by a convenience sample of 751 Chicago taxi drivers. Taxi drivers had low rates of insurance coverage, fruit and vegetable consumption, and physical activity compared with the general Chicago population. Participation in cancer screening tests was also lower for this group. A high proportion of taxi drivers are immigrants. They tend to be highly educated and report a readiness to engage in more health-promoting behaviors. Further research is needed to develop a targeted intervention for this population. PMID:22643623

  7. Taxi Scrip Program in Seattle, Washington

    DOT National Transportation Integrated Search

    1982-09-01

    The Municipality of Metropolitan Seattle (Metro) took over a taxi user-side subsidy program from the City of Seattle in December 1978, which was based on the sale of discounted taxicab scrip. Metro expanded the program, raised the discount, and condu...

  8. Occupational health risks and intervention strategies for US taxi drivers.

    PubMed

    Murray, Kate E; Buul, Abdimalik; Aden, Rasheed; Cavanaugh, Alyson M; Kidane, Luwam; Hussein, Mikaiil; Eastman, Amelia; Checkoway, Harvey

    2017-12-02

    Research has shown that taxi drivers are at risk for numerous health concerns, such as low back and leg pain, linked to their highly sedentary occupation, long work hours and stressors related to the job (e.g. low income, safety threats). The goal of this study was to explore occupational health risks and opportunities for health interventions with taxi drivers using community-based participatory research (CBPR) methods. A mixed methods approach included first a convenience sample of 19 East African taxi drivers participating in focus group discussions. Second, a convenience sample of 75 current taxi drivers (M age = 45.7 years) and 25 non-driver comparison participants (M age = 40.3 years) were recruited to complete a structured self-reported questionnaire and objective measures of health. Health education was provided alongside the research to address common health concerns and to ensure mutual benefit and an action orientation. The focus groups described numerous health concerns that drivers attributed to their occupation, including chronic pain, sleep deprivation, cardiovascular disease, diabetes, kidney disease and eye problems, as the most common. Participants offered ideas for health interventions that include workplace reform and driver education. Quantitative data indicate that 44% of drivers reported their health as 'fair' or 'poor'. Drivers were more likely to report musculoskeletal pain, less sleep, more fatigue and less physical activity as compared to non-drivers. The majority of drivers reported financial and job dissatisfaction. The research provides data to inform targeted health interventions that support the health and safety of taxi drivers. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. [Occupational risk factors and perceptions of air pollution by motorcycle taxi drivers in Cotonou, Benin].

    PubMed

    Lawin, Hervé; Ayi Fanou, Lucie; Hinson, Vikkey; Tollo, Brice; Fayomi, Benjamin; Ouendo, Edgard-Marius

    Motorcycle taxis occupy a major place in urban transport. Motorcycle taxi drivers are exposed to occupational risk factors (ORF) including air pollution. The objective of this study was to evaluate these ORF among motorcycle taxi drivers and their perceptions of air pollution. This mixed study was conducted on motorcycle taxi drivers in Cotonou. The qualitative study was based on focus groups concerning 16 items from the Participatory Occupational Risk Screening Guide (DEPARIS) until saturation and after triangulation of data. The quantitative study consisted of administering a questionnaire addressing socioeconomic and demographic characteristics, cardiopulmonary diseases, and perception of air -pollution risk factors among 397 Cotonou motorcycle taxi drivers. Drivers perceived poor road conditions, effort and handling, and lack of social security as unsatisfactory ORF. Their mean age was 40.95 ± 8.75 years and 45.84% had primary -education. They had been working as motorcycle taxi drivers for an average of 134.95 ± 101.53 months with an average income of FCFA 3138 ± 1238. These occupational factors were significantly associated with cardiopulmonary disorders, observed in 63.2% of drivers. Less than 1/3 of drivers felt that air pollution affected their personal health. Motorcycle taxi drivers have a poor perception of ORF and the severity of exposure to air pollution in this occupation. There is a need to take action to promote the health of this population.

  10. National Ridesharing Demonstration Program : `Maxi-Taxi' Services in the Tidewater Region of Virginia

    DOT National Transportation Integrated Search

    1985-07-01

    In November 1980, the Tidewater Regional Transit Authority (TRT) Implemented a series of shared-ride taxi services under the program name "Maxi-Taxi" (name which was subsequently changed to Maxi-Ride to avert legal challenges). These services, suppli...

  11. Respiratory symptoms and lung function in garage workers and taxi drivers.

    PubMed

    Bener, A; Galadari, I; al-Mutawa, J K; al-Maskari, F; Das, M; Abuzeid, M S

    1998-12-01

    The aim of this study was to determine the prevalence of some respiratory symptoms and possible diseases among occupationally-exposed garage workers and taxi drivers. This study involved 158 garage workers and 165 taxi drivers, matched for age, sex, nationality and duration of employment. The mean age of 158 Indian subcontinent garage workers was 34.4 +/- 10.4 years; their mean height and weight were 167.7 +/- 6.6 cm and 72.0 +/- 12.3 kg respectively, and the mean duration of employment garage workers was 8.8 +/- 7.6 years. The mean age of 165 Indian subcontinent male taxi drivers was 34.5 +/- 7.7 years; their mean height and weight were 168.7 +/- 6.1 cm and 71.3 +/- 12.6 kg respectively; and the mean duration of employment was 7.5 +/- 5.4 years. The data on chronic respiratory symptoms showed that garage workers had higher prevalence of symptoms than taxi drivers being significantly greater for chronic phlegm, (p < 0.007); dyspneoa (p < 0.001); and sinusitis (p < 0.03). A higher prevalence of all acute symptoms was recorded in garage workers than in taxi drivers, although the differences were significant only for throat (p < 0.02), hearing problems (p < 0.002); nose (dryness, bleeding and secretion) (p < 0.008); and low back pain (p < 0.05). Almost all forced spirometric tests in the exposed garage workers were lower than in taxi drivers. The results of stepwise multiple regression analysis showed that only phlegm, sinusitis, hearing problems, nasal catarrh, throat, low back pain, smoking and FEF25-75, variables were statistically significant predictors as risk factors. In conclusion, the present study suggests that a high prevalence of respiratory symptoms is associated with exposure to motor vehicle exhaust emission in garage working places. Long-term working as garage workers in the United Arab Emirates (UAE), may be associated with the development of chronic respiratory symptoms and have effects on their daily life and health.

  12. Shared-Ride Taxi Service in Boston, MA

    DOT National Transportation Integrated Search

    1985-03-01

    This report presents an evaluation of the Boston Shared-Ride Taxi Demonstration. The City of Boston's Traffic and Parking Department, the project grantee, designed a shared-ride service for Boston's Allston-Brighton neighborhood; Boston Cab Associati...

  13. Filters from taxis air conditioning system: A tool to characterize driver's occupational exposure to bioburden?

    PubMed

    Viegas, Carla; Monteiro, Ana; Dos Santos, Mateus; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Quintal Gomes, Anita; Marchand, Geneviève; Lacombe, Nancy; Viegas, Susana

    2018-07-01

    Bioburden proliferation in filters from air conditioning systems of taxis represents a possible source of occupational exposure. The aim of this study was to determine the occurrence of fungi and bacteria in filters from the air conditioning system of taxis used for patient transportation and to assess the exposure of drivers to bioburden. Filters from the air conditioning systems of 19 taxis and 28 personal vehicles (used as controls) operating in three Portuguese cities including the capital Lisbon, were collected during the winter season. The occurrence and significance of bioburden detected in the different vehicles are reported and discussed in terms of colony-forming units (CFU) per 1 m 2 of filter area and by the identification of the most frequently detected fungal isolates based on morphology. Azole-resistant mycobiota, fungal biomass, and molecular detection of Aspergillus species/strains were also determined. Bacterial growth was more prevalent in taxis (63.2%) than in personal vehicles (26.3%), whereas fungal growth was more prevalent in personal vehicles (53.6%) than in taxis (21.1-31.6%). Seven different azole-resistant species were identified in this study in 42.1% taxi filters. Levels of fungal biomass were above the detection limit in 63% taxi filters and in 75% personal vehicle filters. No toxigenic species were detected by molecular analysis in the assessed filters. The results obtained show that bioburden proliferation occurs widely in filters from the air conditioning systems of taxis, including the proliferation of azole-resistant fungal species, suggesting that filters should be replaced more frequently. The use of culture based-methods and molecular tools combined enabled an improved risk characterization in this setting. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Math on the Job. Taxi Driver.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This booklet is intended to help mainstreamed mentally retarded, emotionally disturbed, or learning disabled high school students acquire a basic understanding of the responsibilities and working conditions of taxi drivers and to practice basic math skills necessary in the occupation. The first section provides a brief introduction to the…

  15. Prevalence and factors associated with road traffic crash among taxi drivers in Hanoi, Vietnam.

    PubMed

    La, Quang Ngoc; Lee, Andy H; Meuleners, Lynn B; Van Duong, Dat

    2013-01-01

    Injury due to road traffic crash is a major cause of ill health and premature deaths in developing countries. Taxis provide a main mode of public transport in Vietnam but there has been little research on the risk of crash for taxi drivers. This retrospective study collected information on taxi crashes for the period 2006-2009 by interviewing drivers from five taxi companies in Hanoi, Vietnam, using a structured questionnaire. Of the total 1214 participants recruited, 276 drivers reported at least one crash, giving an overall crash prevalence of 22.7%. Among the crashed group, 50 drivers (18.1%) were involved in two to four crashes. Logistic regression analysis further identified age of driver, type of driving licence, employment status, perceived sufficiency of income, seat-belt usage, and traffic infringement history to be significantly associated with the crash risk. Further prospective and qualitative studies are recommended to provide detailed crash characteristics as well as behaviour and perception of taxi drivers, so that an effective intervention can be developed to improve road safety and to prevent injury of these commercial drivers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. 76 FR 33639 - Safety Zone; New York Water Taxi 10th Anniversary Fireworks

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-09

    ...-AA00 Safety Zone; New York Water Taxi 10th Anniversary Fireworks, Upper New York Bay, Red Hook, NY... New York Water Taxi. The fireworks will commence at 9 p.m. on June 21, 2011 and will last... CFR Part 165 Harbors, Marine safety, Navigation (water), Reporting and recordkeeping requirements...

  17. On-road emission characteristics of CNG-fueled bi-fuel taxis

    NASA Astrophysics Data System (ADS)

    Yao, Zhiliang; Cao, Xinyue; Shen, Xianbao; Zhang, Yingzhi; Wang, Xintong; He, Kebin

    2014-09-01

    To alleviate air pollution and lessen the petroleum demand from the motor vehicle sector in China, natural gas vehicles (NGVs) have been rapidly developed over the last several years. However, the understanding of the real-world emissions of NGVs is very limited. In this study, the emissions from 20 compressed-natural-gas-fueled bi-fuel taxis were measured using a portable emission measurement system (PEMS) under actual driving conditions in Yichang, China. The emission characteristics of the tested vehicles were analyzed, revealing that the average CO2, CO, HC and NOx emissions from the tested compressed-natural-gas (CNG) taxis under urban driving conditions were 1.6, 4.0, 2.0 and 0.98 times those under highway road conditions, respectively. The CO, HC and NOx emissions from Euro 3 CNG vehicles were approximately 40%, 55% and 44% lower than those from Euro 2 vehicles, respectively. Compared with the values for light-duty gasoline vehicles reported in the literature, the CO2 and CO emissions from the tested CNG taxis were clearly lower; however, significant increases in the HC and NOx emissions were observed. Finally, we normalized the emissions under the actual driving cycles of the entire test route to the New European Driving Cycle (NEDC)-based emissions using a VSP modes method developed by North Carolina State University. The simulated NEDC-based CO emissions from the tested CNG taxis were better than the corresponding emissions standards, whereas the simulated NEDC-based HC and NOx emissions greatly exceeded the standards. Thus, more attention should be paid to the emissions from CNG vehicles. As for the CNG-fueled bi-fuel taxis currently in use, the department of environmental protection should strengthen their inspection and supervision to reduce the emissions from these vehicles. The results of this study will be helpful in understanding and controlling emissions from CNG-fueled bi-fuel vehicles in China.

  18. 14 CFR Appendix C to Part 330 - Forms for Air Taxi Operators

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Forms for Air Taxi Operators C Appendix C to Part 330 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION... Part 330—Forms for Air Taxi Operators ER20AU02.009 ER20AU02.010 ER20AU02.011 ER20AU02.012 ER20AU02.013...

  19. Monopoly Profits: The Market for Taxi Licenses.

    ERIC Educational Resources Information Center

    Keane, Michael

    1981-01-01

    Presents a case study dealing with open versus closed markets for use in college economics classes. Using the example of the taxi license monopoly in Dublin, Ireland, students examine how theories of supply and demand explain the characteristics of open and closed markets. (AM)

  20. [Association between psychosocial aspects of work and quality of life among motorcycle taxi drivers].

    PubMed

    Teixeira, Jules Ramon Brito; Boery, Eduardo Nagib; Casotti, Cezar Augusto; Araújo, Tânia Maria de; Pereira, Rafael; Ribeiro, Ícaro José Santos; Rios, Marcela Andrade; Amorim, Camila Rego; Moreira, Ramon Missias; Boery, Rita Narriman Silva de Oliveira; Sales, Zenilda Nogueira

    2015-01-01

    This study aimed to evaluate the quality of life of motorcycle taxi drivers and the association with psychosocial characteristics of their work. This was a cross-sectional epidemiological study with a sample of 400 motorcycle taxi drivers in Jequié, Bahia State, Brazil. The study used a form containing demographic and socioeconomic data, WHO Quality of Life-Bref Questionnaire (WHOQOL-Bref), and the Job Content Questionnaire (JCQ). Motorcycle taxi drivers with greater decision-making control over their work showed better self-rated quality of life in the psychological domain; those with high psychological demands presented better self-rated quality of life in the social relations and environmental domains; those with high strain and active work showed better self-rated quality of life in the social and environmental domains. The psychosocial work environment and especially decision-making autonomy were thus important determinants of self-rated quality of life in this group of motorcycle taxi drivers.

  1. Impact of urban built environment on urban short-distance taxi travel: the case of Shanghai

    NASA Astrophysics Data System (ADS)

    Wu, Zhuoye; Zhuo, Jian

    2018-05-01

    The excessive individual motorized transport is the main cause of urban congestion and generates negative consequences on urban environmental quality, energy consumption, infrastructure supply and urban security. Bicycle can compete effectively with automobile for short-distance travels within 3km. If we take action to encourage the rider to shift from automobile to bike for the short-distance travels, it leaves us a great chance to reduce the modal share of individual motorized mode. This paper focus on the spatial impact of built environment on short-distance taxi riders’ travel behaviour. The data sources include taxi trajectory data for a week, demographic data of the Sixth National Census, POI data. In this paper, we figure out the volumes and spatial distribution of short-distance taxi travel in the central city of Shanghai. We build a multiple regression model to quantitative analyze the impact of urban built environment on urban short-distance taxi travel. The findings explain the spatial distribution short-distance taxi travel. In the conclusion, some advice are provided on how planners change the spatial settings to discourage short-distance individual motorized travel.

  2. Terminal area automatic navigation, guidance, and control 1: Automatic rollout, turnoff, and taxis

    NASA Technical Reports Server (NTRS)

    Pines, S.

    1981-01-01

    A study developed for the TCV B-737, designed to apply existing navigation aids plus magnetic leader cable signals and develop breaking and reverse thrust guidance laws to provide for rapid automated rollout, turnoff, and taxi to reduce runway occupation time for a wide variety of landing conditions for conventional commercial-type aircraft, is described. Closed loop guidance laws for braking and reverse thrust are derived for rollout, turnoff, and taxi, as functions of the landing speed, the desired taxi speed and the distance to go. Brake limitations for wet runway conditions and reverse thrust limitations are taken into account to provide decision rules to avoid tire skid and to choose an alternate turnoff point, farther down the runway, to accommodate extreme landing conditions.

  3. Shared Ride Taxi Feeder Service in Memphis, TN

    DOT National Transportation Integrated Search

    1988-03-01

    From May 1983 through October 1984, the Memphis Area Transit Authority (MATA) conducted the Taxi Feeder Demonstration Project. It entailed the operation of fixed-route feeder services through three low-density neighborhoods and one industrial park, c...

  4. The relation between working conditions, aberrant driving behaviour and crash propensity among taxi drivers in China.

    PubMed

    Wang, Yonggang; Li, Linchao; Prato, Carlo G

    2018-04-03

    Although the taxi industry is playing an important role in Chinese everyday life, little attention has been posed towards occupational health issues concerning the taxi drivers' working conditions, driving behaviour and road safety. A cross-sectional survey was administered to 1021 taxi drivers from 21 companies in four Chinese cities and collected information about (i) sociodemographic characteristics, (ii) working conditions, (iii) frequency of daily aberrant driving behaviour, and (iv) involvement in property-damage-only (PDO) and personal injury (PI) crashes over the past two years. A hybrid bivariate model of crash involvement was specified: (i) the hybrid part concerned a latent variable model capturing unobserved traits of the taxi drivers; (ii) the bivariate part modelled jointly both types of crashes while capturing unobserved correlation between error terms. The survey answers paint a gloomy picture in terms of workload, as taxi drivers reported averages of 9.4 working hours per day and 6.7 working days per week that amount on average to about 63.0 working hours per week. Moreover, the estimates of the hybrid bivariate model reveal that increasing levels of fatigue, reckless behaviour and aggressive behaviour are positively related to a higher propensity of crash involvement. Lastly, the heavy workload is also positively correlated with the higher propensity of crashing, not only directly as a predictor of crash involvement, but also indirectly as a covariate of fatigue and aberrant driving behaviour. The findings from this study provide insights into potential strategies for preventive education and taxi industry management to improve the working conditions and hence reduce fatigue and road risk for the taxi drivers. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Shared-Ride Taxi Computer Control System Requirements Study

    DOT National Transportation Integrated Search

    1977-08-01

    The technical problem of scheduling and routing shared-ride taxi service is so great that only computers can handle it efficiently. This study is concerned with defining the requirements of such a computer system. The major objective of this study is...

  6. Constitutive expression of the xylanase inhibitor TAXI-III delays Fusarium head blight symptoms in durum wheat transgenic plants.

    PubMed

    Moscetti, Ilaria; Tundo, Silvio; Janni, Michela; Sella, Luca; Gazzetti, Katia; Tauzin, Alexandra; Giardina, Thierry; Masci, Stefania; Favaron, Francesco; D'Ovidio, Renato

    2013-12-01

    Cereals contain xylanase inhibitor (XI) proteins which inhibit microbial xylanases and are considered part of the defense mechanisms to counteract microbial pathogens. Nevertheless, in planta evidence for this role has not been reported yet. Therefore, we produced a number of transgenic plants constitutively overexpressing TAXI-III, a member of the TAXI type XI that is induced by pathogen infection. Results showed that TAXI-III endows the transgenic wheat with new inhibition capacities. We also showed that TAXI-III is correctly secreted into the apoplast and possesses the expected inhibition parameters against microbial xylanases. The new inhibition properties of the transgenic plants correlate with a significant delay of Fusarium head blight disease symptoms caused by Fusarium graminearum but do not significantly influence leaf spot symptoms caused by Bipolaris sorokiniana. We showed that this contrasting result can be due to the different capacity of TAXI-III to inhibit the xylanase activity of these two fungal pathogens. These results provide, for the first time, clear evidence in planta that XI are involved in plant defense against fungal pathogens and show the potential to manipulate TAXI-III accumulation to improve wheat resistance against F. graminearum.

  7. 14 CFR 330.29 - What information must air taxi operators submit on Form 330 (Final) and Form 330-C?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false What information must air taxi operators... COMPENSATION OF AIR CARRIERS Application Procedures § 330.29 What information must air taxi operators submit on Form 330 (Final) and Form 330-C? As an air taxi operator, you must complete Form 330 (Final) in...

  8. 14 CFR 330.29 - What information must air taxi operators submit on Form 330 (Final) and Form 330-C?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false What information must air taxi operators... COMPENSATION OF AIR CARRIERS Application Procedures § 330.29 What information must air taxi operators submit on Form 330 (Final) and Form 330-C? As an air taxi operator, you must complete Form 330 (Final) in...

  9. Talent in the taxi: a model system for exploring expertise

    PubMed Central

    Woollett, Katherine; Spiers, Hugo J.; Maguire, Eleanor A.

    2009-01-01

    While there is widespread interest in and admiration of individuals with exceptional talents, surprisingly little is known about the cognitive and neural mechanisms underpinning talent, and indeed how talent relates to expertise. Because many talents are first identified and nurtured in childhood, it can be difficult to determine whether talent is innate, can be acquired through extensive practice or can only be acquired in the presence of the developing brain. We sought to address some of these issues by studying healthy adults who acquired expertise in adulthood. We focused on the domain of memory and used licensed London taxi drivers as a model system. Taxi drivers have to learn the layout of 25 000 streets in London and the locations of thousands of places of interest, and pass stringent examinations in order to obtain an operating licence. Using neuropsychological assessment and structural and functional magnetic resonance imaging, we addressed a range of key questions: in the context of a fully developed brain and an average IQ, can people acquire expertise to an exceptional level; what are the neural signatures, both structural and functional, associated with the use of expertise; does expertise change the brain compared with unskilled control participants; does it confer any cognitive advantages, and similarly, does it come at a cost to other functions? By studying retired taxi drivers, we also consider what happens to their brains and behaviour when experts stop using their skill. Finally, we discuss how the expertise of taxi drivers might relate to the issue of talent and innate abilities. We suggest that exploring talent and expertise in this manner could have implications for education, rehabilitation of patients with cognitive impairments, understanding individual differences and possibly conditions such as autism where exceptional abilities can be a feature. PMID:19528024

  10. Aeroassisted manned transfer vehicle (TAXI) for advanced Mars Transportation: NASA/USRA 1987 Senior Design Project

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A conceptual design study of an aeroassisted orbital transfer vehicle is discussed. Nicknamed TAXI, it will ferry personnel and cargo: (1) between low Earth orbit and a spacecraft circling around the Sun in permanent orbit intersecting gravitational fields of Earth and Mars, and (2) between the cycling spacecraft and a Mars orbiting station, co-orbiting with Phobos. Crew safety and mission flexibility (in terms of ability to provide a wide range of delta-V) were given high priority. Three versions were considered, using the same overall configuration based on a low L/D aerobrake with the geometry of a raked off elliptical cone with ellipsoidal nose and a toroidal skirt. The propulsion system consists of three gimballed LOX/LH2 engines firing away from the aerobrake. The versions differ mainly in the size of the aeroshields and propellant tanks. TAXI A version resulted from an initial effort to design a single transfer vehicle able to meet all delta-V requirements during the 15-year period (2025 to 2040) of Mars mission operations. TAXI B is designed to function with the cycling spacecraft moving in a simplified, nominal trajectory. On Mars missions, TAXI B would be able to meet the requirements of all the missions with a relative approach velocity near Mars of less than 9.3 km/sec. Finally, TAXI C is a revision of TAXI A, a transfer vehicle designed for missions with a relative velocity near Mars larger than 9.3 km/sec. All versions carry a crew of 9 (11 with modifications) and a cargo of 10000 lbm. Trip duration varies from 1 day for transfer from LEO to the cycling ship to nearly 5 days for transfer from the ship to the Phobos orbit.

  11. Taxi Regulatory Revision in Portland Oregon : Background and Implementation

    DOT National Transportation Integrated Search

    1980-09-01

    The Portland Council has adopted successive waves of taxi regulatory revisions. Effective in Marh, 1979, the previous ceiling on total permits was removed and entry was opened to qualified applicats. The new reulations also provided for flat, discoun...

  12. Health Status, Intention to Seek Health Examination, and Participation in Health Education Among Taxi Drivers in Jinan, China

    PubMed Central

    Yang, Yan; Fan, Xiao-sheng; Tian, Cui-huan; Zhang, Wei; Li, Jie; Li, Shu-qing

    2014-01-01

    Background: Taxi drivers are exposed to various risk factors such as work overload, stress, an irregular diet, and a sedentary lifestyle, which make these individuals vulnerable to many diseases. This study was designed to assess the health status of this occupational group. Objectives: The objective was to explore the health status, the intention to seek health examination, and participation in health education among taxi drivers in Jinan, China. Patients and Methods: The sample-size was determined scientifically. The systematic sampling procedure was used for selecting the sample. Four hundred taxi drivers were randomly selected from several taxi companies in Jinan. In total, 396 valid questionnaires (from 370 males and 26 females) were returned. Health status, intention to seek health examination, and participation in health education were assessed by a self-designed questionnaire. Other personal information including sex, age, ethnicity, marital status, years of employment as a taxi driver, education level, and habits were also collected. Results: This survey revealed that 54.8% of taxi drivers reported illness in the last two weeks and 44.7% of participants reported chronic diseases. The prevalence rates of hypertension, diabetes mellitus, gastroenteritis, arthritis, and heart disease were 18.2%, 8.8%, 26%, 18.4%, and 4.8% of questioned taxi drivers, respectively. Significant self-reported symptoms included fatigue, waist and back pain, headache, dyspepsia, and dry throat affecting 49.7%, 26.2%, 23.5%, 26%, and 27% of participants, respectively. In total, 90.1% of subjects thought that it was necessary to receive a regular health examination. Only 17.9% of subjects had been given information about health education, and significantly, more than 87% of subjects who had been given information about health education reported that the information had been helpful. Conclusions: Taxi drivers’ health was poor in our survey. Thus, using health education interventions

  13. Effect of Surface Traffic Count on Taxi Time at Dallas-Fort Worth (DFW) International Airport

    NASA Technical Reports Server (NTRS)

    Kistler, Matthew Stephen; Gupta, Gautam

    2008-01-01

    As the amount of air traffic increases over the years, most airports simply do not have the means of expanding to handle the intensified traffic on the surface that will ensue. Precise surveillance equipment and automation concepts, as well as advanced surface traffic algorithms are being developed to improve airport efficiency. These surface algorithms require inputs unique to each airport to ensure maximum efficiency, and minimal taxi delay. This study analyzes surface traffic at Dallas-Fort Worth International Airport (DFW) to determine the effect of the number of aircraft on the surface and the amount of stop and go situations they experience to the amount of additional taxi time encountered. If the surface capacity of an airport is known, minimal delay can be accomplished by limiting the number of taxiing aircraft to that capacity. This concept is related to highways, where traffic flow drastically decreases as more cars occupy the road. An attempt to minimize this effect on highways is seen with the use of metering lights at freeway on-ramps. Since the surface traffic at airports is highly regulated, and aircraft are less mobile on the ground, limiting the surface count to a certain number can greatly reduce the amount of additional taxi time encountered, as well as reduce hazardous emissions. This study will also find the regions of an airport that encounter the most additional taxi time when the number of aircraft in that area is increased. This could help surface traffic algorithms avoid congesting that area, or re-route aircraft to different runways when that area reaches its capacity. The relationship between the amount of stop and go situations an aircraft encounters and their effect on the taxi time of that aircraft will also be investigated. This will help to determine the effect of holding an aircraft on the taxiway as opposed to re-routing it. The lesser of the two should be used when developing surface traffic algorithms to further minimize the

  14. Taxi trips distribution modeling based on Entropy-Maximizing theory: A case study in Harbin city-China

    NASA Astrophysics Data System (ADS)

    Tang, Jinjun; Zhang, Shen; Chen, Xinqiang; Liu, Fang; Zou, Yajie

    2018-03-01

    Understanding Origin-Destination distribution of taxi trips is very important for improving effects of transportation planning and enhancing quality of taxi services. This study proposes a new method based on Entropy-Maximizing theory to model OD distribution in Harbin city using large-scale taxi GPS trajectories. Firstly, a K-means clustering method is utilized to partition raw pick-up and drop-off location into different zones, and trips are assumed to start from and end at zone centers. A generalized cost function is further defined by considering travel distance, time and fee between each OD pair. GPS data collected from more than 1000 taxis at an interval of 30 s during one month are divided into two parts: data from first twenty days is treated as training dataset and last ten days is taken as testing dataset. The training dataset is used to calibrate model while testing dataset is used to validate model. Furthermore, three indicators, mean absolute error (MAE), root mean square error (RMSE) and mean percentage absolute error (MPAE), are applied to evaluate training and testing performance of Entropy-Maximizing model versus Gravity model. The results demonstrate Entropy-Maximizing model is superior to Gravity model. Findings of the study are used to validate the feasibility of OD distribution from taxi GPS data in urban system.

  15. Spatial-temporal travel pattern mining using massive taxi trajectory data

    NASA Astrophysics Data System (ADS)

    Zheng, Linjiang; Xia, Dong; Zhao, Xin; Tan, Longyou; Li, Hang; Chen, Li; Liu, Weining

    2018-07-01

    Deep understanding of residents' travel patterns would provide helpful insights into the mechanisms of many socioeconomic phenomena. With the rapid development of location-aware computing technologies, researchers have easy access to large quantities of travel data. As an important data source, taxi trajectory data are featured by their high quality, good continuity and wide distribution, making it suitable for travel pattern mining. In this paper, we use taxi trajectory data to study spatial-temporal characterization of urban residents' travel patterns from two aspects: attractive areas and hot paths. Firstly, a framework of trajectory preprocessing, including data cleaning and extracting the taxi passenger pick-up/drop-off points, is presented to reduce the noise and redundancy in raw trajectory data. Then, a grid density based clustering algorithm is proposed to discover travel attractive areas in different periods of a day. On this basis, we put forward a spatial-temporal trajectory clustering method to discover hot paths among travel attractive areas. Compared with previous algorithms, which only consider the spatial constraint between trajectories, temporal constraint is also considered in our method. Through the experiments, we discuss how to determine the optimal parameters of the two clustering algorithms and verify the effectiveness of the algorithms using real data. Furthermore, we analyze spatial-temporal characterization of Chongqing residents' travel pattern.

  16. Motorcycle safety among motorcycle taxi drivers and nonoccupational motorcyclists in developing countries: A case study of Maoming, South China.

    PubMed

    Wu, Connor Y H; Loo, Becky P Y

    2016-01-01

    An increasing number of motorcycle taxis have been involved in traffic crashes in many developing countries. This study examines the characteristics of both motorcycle taxi drivers and nonoccupational motorcyclists, investigates the risks they pose to road safety, and provides recommendations to minimize their risks. Based on the data collected from a questionnaire survey of 867 motorcycle taxi drivers and 2,029 nonoccupational motorcyclists in Maoming, South China, comparisons were made to analyze differences of personal attributes, attitudes toward road safety, and self-reported behavior of the 2 groups. Results of the chi-square tests show that not only motorcycle taxi drivers but also nonoccupational motorcyclists in Maoming held poor attitudes toward road safety and both groups reported unsafe driving behavior. There is much room for improving local road safety education among all motorcyclists in Maoming. Yet, motorcycle taxi drivers were more likely to pose road safety risks than nonoccupational motorcyclists under some circumstances, such as speeding late at night or early in the morning, not requiring passengers to wear helmets, and running a red light. The results of the binary logistic regression model show that possessing a vehicle license for a motorcycle or not was the common significant predictor for unsafe driving behavior of motorcycle taxi drivers and nonoccupational motorcyclists. Therefore, enforcement against all motorcyclists not showing vehicle licenses for their motorcycles should be stepped up. Motorcycle safety is largely poor in Maoming. Therefore, efforts to improve motorcycle safety should be strengthened by targeting not only motorcycle taxi drivers but also nonoccupational motorcyclists.

  17. Indianapolis Experience with Open Entry in the Taxi Industry

    DOT National Transportation Integrated Search

    1980-09-01

    During the early 1970s the City of Indianapolis reversed a long-standing policy of closed entry into the taxi industry by redistributing many of the existing permits. This report is an account of the Indianapolis experience with open entry. It is bas...

  18. Compliance and enforcement of a partial smoking ban in Lisbon taxis: an exploratory cross-sectional study.

    PubMed

    Ravara, Sofia B; Castelo-Branco, Miguel; Aguiar, Pedro; Calheiros, Jose M

    2013-02-14

    Research evaluating enforcement and compliance with smoking partial bans is rather scarce, especially in countries with relative weak tobacco control policies, such as Portugal. There is also scarce evidence on specific high risk groups such as vehicle workers. In January 2008, Portugal implemented a partial ban, followed by poor enforcement. The purpose of this study was to explore the effectiveness of a partial smoking ban in a pro-smoking environment, specifically transportation by taxi in the city of Lisbon. Ban effectiveness was generally defined by ban awareness and support, compliance and enforcement. Exploratory cross-sectional study; purposive sampling in selected Lisbon streets. Structured interviews were conducted by trained researchers while using taxi services (January 2009-December 2010). 250 taxi drivers (98.8% participation rate). Chi-square, McNemar, Man Whitney tests and multiple logistic regression were performed. Of the participants, 249 were male; median age was 53.0 years; 43.6% were current smokers. Most participants (82.8%) approved comprehensive bans; 84.8% reported that clients still asked to smoke in their taxis; 16.8% allowed clients to smoke. Prior to the ban this value was 76.9% (p < 0.001). The major reason for not allowing smoking was the legal ban and associated fines (71.2%). Of the smokers, 66.1% admitted smoking in their taxi. Stale smoke smells were detected in 37.6% of the cars. None of the taxi drivers did ever receive a fine for non-compliance. Heavy smoking, night-shift and allowing smoking prior the ban predicted non-compliance. Despite the strong ban support observed, high smoking prevalence and poor enforcement contribute to low compliance. The findings also suggest low compliance among night-shift and vehicle workers. This study clearly demonstrates that a partial and poorly-enforced ban is vulnerable to breaches, and highlights the need for clear and strong policies.

  19. [A KABP (knowledge, attitude, belief and behavior) study about AIDS among taxi drivers and hotel attendants in Beijing].

    PubMed

    Zhang, X; Luo, B; Zhang, K

    1994-12-01

    This article reports the KABP study on 448 taxi drivers and 556 hotel attendants in Beijing for the first time in China. A self-administered questionnaire was used to investigate knowledge, attitude, belief and practice (KABP) about AIDS. In terms of knowledge, 23.8% of hotel attendants and 36.8% of taxi drivers did not know that contact with blood could transmit HIV. Thirtyfive percent of hotel attendants and 42.2% of taxi drivers did not believe that intravenous drug users were at high risk. Some drivers (13.6%) and hotel attendants (3.4%) reported having multiple sexual partners. Forty-one point nine percent of taxi drivers and 16.6% of hotel attendants preferred the idea of multiple sexual partners. Among hotel attendants, a negative association was found between knowledge about AIDS and multiple sexual behavior (P < 0.01). Regarding attitude toward condom use, 56.2% of taxi drivers and 47.8% of hotel attendants who have had a sexual experience thought that condom use interfered with sexual pleasure. Seventy-six point eight percent of taxi drivers and 79.8% of hotel attendants believed that they could change their behaviors in order to minimize the chances of getting HIV. This study indicates that HIV education is important in reducing the number of sexual partners and promoting the use of safe sex practices like condom use. Furthermore, as reported by the study population, education can change behavior.

  20. Physical activity overcomes the effects of cumulative work time on hypertension prevalence among Brazilian taxi drivers.

    PubMed

    Vieira, Marcelo C; Sperandei, Sandro; Reis, Arianne C

    2016-05-01

    The aim of this study was to assess the physical activity profile of taxi drivers and its relationship with hypertension prevalence in this group of workers. Cross sectional exploratory study. Between November 2008 and April 2009, 491 taxi drivers from Rio de Janeiro, Brazil, answered a questionnaire focusing on previous hypertension diagnosis, occupational characteristics and physical activity habits. Two logistic models were developed to determine risk factors related to hypertension and to find variables associated with a higher probability of sedentarism. Hypertension prevalence was 22.6%. The workload of the group investigated was high. Results indicate that 'age', 'Body Mass Index', 'physical activity', and 'years as a taxi driver' are related to the probability of hypertension. Physical activity was shown to be a protection factor for hypertension, even considering the deleterious effect of time as a taxi driver. Our results also determined that the practice of physical activity is influenced by age, level of education and workload. It is recommended that programs to combat sedentary lifestyles as well as measures to reduce workloads be developed as strategies to prevent hypertension.

  1. Physical activity overcomes the effects of cumulative work time on hypertension prevalence among Brazilian taxi drivers.

    PubMed

    Vieira, M C; Sperandei, S; Reis, A

    2015-02-10

    The aim of this study was to assess the physical activity profile of taxi drivers and its relationship with hypertension prevalence in this group of workers. Cross sectional exploratory study. Between November 2008 and April 2009, 491 taxi drivers from Rio de Janeiro, Brazil, answered a questionnaire focusing on previous hypertension diagnosis, occupational characteristics and physical activity habits. Two logistic models were developed to determine risk factors related to hypertension and to find variables associated with a higher probability of sedentarism. Hypertension prevalence was 22.6%. The workload of the group investigated was high. Results indicate that 'age', 'body mass index', 'physical activity', and 'years as a taxi driver' are related to the probability of hypertension. Physical activity was shown to be a protection factor for hypertension, even considering the deleterious effect of time as a taxi driver. Our results also determined that the practice of physical activity is influenced by age, level of education and workload. It is recommended that programs to combat sedentary lifestyles as well as measures to reduce workloads be developed as strategies to prevent hypertension.

  2. 76 FR 65769 - Application of Friendship Airways, Inc. d/b/a Yellow Air Taxi for Commuter Authority

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ... DEPARTMENT OF TRANSPORTATION Office of the Secretary Application of Friendship Airways, Inc. d/b/a Yellow Air Taxi for Commuter Authority AGENCY: Department of Transportation. ACTION: Notice of Order to... issued to Friendship Airways, Inc. d/b/a Yellow Air Taxi and deny its application to resume commuter...

  3. Lifestyle risk factors for cardiovascular disease and diabetic risk in a sedentary occupational group: the Galway taxi driver study.

    PubMed

    Martin, W P; Sharif, F; Flaherty, G

    2016-05-01

    Taxi drivers are at increased risk of cardiovascular disease (CVD), something which persists after correcting for the overrepresentation of traditional risk factors for CVD in this cohort. The contribution of lifestyle risk factors to this residually elevated CVD risk remains under-evaluated. We aimed to determine the prevalence of lifestyle risk factors for CVD, self-reported medical risk factors for CVD, and future risk of type 2 diabetes amongst Irish taxi drivers. Male taxi drivers with no history of CVD and type 2 diabetes and working in Galway city in the west of Ireland were invited to participate. Physical activity levels, dietary patterns, anthropometry, smoking, hypertension, hypercholesterolaemia, and Finnish Diabetes Risk Score (FINDRISC) values were recorded in a cross-sectional manner. 41 taxi drivers (mean age 56.7 ± 9.8 years) participated. 37 % were insufficiently active based on self-report, although only 8 % objectively achieved 10, 000 steps per day. Mean modified Mediterranean diet score (mMDS) was 4.6 ± 2.2, and only 13 % of participants had a normal body mass index (BMI) or waist circumference (WC). Those who worked for taxi companies tended to have a higher BMI (p = .07) and WC (p = .04) by multivariable regression. 22 % were current smokers, although a quit rate of 72 % was observed amongst the 78 % of taxi drivers who had ever smoked. 25 % were at high or very high risk of future type 2 diabetes. Lifestyle risk factors for CVD and dysglycaemia are prevalent amongst Irish taxi drivers.

  4. The Aircraft Electric Taxi System: A Qualitative Multi Case Study

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas Frank

    The problem this research addresses is the airline industry, and the seemingly unwillingness attitude towards adopting ways to taxi aircraft without utilizing thrust from the main engines. The purpose of the study was to get a better understanding of the decision-making process of airline executives, in respect to investing in cost saving technology. A qualitative research method is used from personal interviews with 24 airline executives from two major U.S. airlines, related industry journal articles, and aircraft performance data. The following three research questions are addressed. RQ1. Does the cost of jet fuel influence airline executives' decision of adopting the aircraft electric taxi system technology? RQ2 Does the measurable payback period for a return on investment influence airline executives' decision of adopting ETS technology? RQ3. Does the amount of government assistance influence airline executives' decision of adopting ETS technology? A multi case research study design is used with a triangulation technique. The participant perceptions indicate the need to reduce operating costs, they have concerns about investment risk, and they are in favor of future government sponsored performance improvement projects. Based on the framework, findings and implications of this study, a future research paper could focus on the positive environmental effects of the ETS application. A study could be conducted on current airport area air quality and the effects that aircraft main engine thrust taxiing has on the surrounding air quality.

  5. Ground Taxi Navigation Problems and Training Solutions

    NASA Technical Reports Server (NTRS)

    Quinn, Cheryl; Walter, Kim E.; Rosekind, Mark (Technical Monitor)

    1997-01-01

    Adverse weather conditions can put considerable strain on the National Airspace System. Even small decreases in visibility on the airport surface can create delays, hinder safe movement and lead to errors. Studies of Aviation Safety Reporting System (ASRS) surface movement incidents support the need for technologies and procedures to improve ground operations in low-visibility conditions. This study examined 139 ASRS reports of low-visibility surface movement incidents at 10 major U.S. airports. Errors were characterized in terms of incident type, contributing factors and consequences. The incidents in the present sample were comprised of runway transgressions, taxiway excursions and ground conflicts. The primary contributing factors were Airport Layout and Markings, Communication and Distraction. In half the incidents the controller issued a new clearance or the flight crew took an evasive action and in the remaining half, no recovery attempt was made because the error was detected after the fact. By gaining a better understanding the factors that affect crew navigation in low visibility and the types of errors that are likely to occur, it will be possible to develop more robust technologies to aid pilots in the ground taxi task. Implications for crew training and procedure development for low-visibility ground taxi are also discussed.

  6. Step On It! - Workplace cardiovascular risk assessment of New York City yellow taxi drivers

    PubMed Central

    Gany, Francesca; Bari, Sehrish; Gill, Pavan; Ramirez, Julia; Ayash, Claudia; Loeb, Rebecca; Aragones, Abraham; Leng, Jennifer

    2015-01-01

    Background Multiple factors associated with taxi driving can increase the risk of cardiovascular disease (CVD) in taxi drivers. Methods This paper describes the results of Step On It!, which assessed CVD risk factors among New York City taxi drivers at John F. Kennedy International Airport. Drivers completed an intake questionnaire and free screenings for blood pressure, glucose and body mass index (BMI). Results 466 drivers participated. 9% had random plasma glucose values >200 mg/dl. 77% had elevated BMIs. Immigrants who lived in the U.S. for >10 years had 2.5 times the odds (CI: 1.1–5.9) of having high blood pressure compared to newer immigrants. Discussion Abnormalities documented in this study were significant, especially for immigrants with greater duration of residence in the U.S., and underscore the potential for elevated CVD risk in this vulnerable population, and the need to address this risk through frameworks that utilize multiple levels of intervention. PMID:25680879

  7. Enhancing taxi performance under low visibility : are moving maps enough?

    DOT National Transportation Integrated Search

    1997-09-01

    We report the results of an experiment evaluating the separate and combined effects of a 3-D perspective moving map and newly developed Head-Up Display symbology on taxi performance in low visibility. Nine commercial airline pilots completed a series...

  8. Late-Night Shared-Ride Taxi Transit in Ann Arbor, MI

    DOT National Transportation Integrated Search

    1984-10-01

    The Ann Arbor Transportation Authority introduced Night Ride, a late-night shared-ride taxi transit service, in mid-March 1982. The service was provided through a contract with a local taxicab company and funded through a demonstration grant from the...

  9. The xylanase inhibitor TAXI-III counteracts the necrotic activity of a Fusarium graminearum xylanase in vitro and in durum wheat transgenic plants.

    PubMed

    Moscetti, Ilaria; Faoro, Franco; Moro, Stefano; Sabbadin, Davide; Sella, Luca; Favaron, Francesco; D'Ovidio, Renato

    2015-08-01

    The xylanase inhibitor TAXI-III has been proven to delay Fusarium head blight (FHB) symptoms caused by Fusarium graminearum in transgenic durum wheat plants. To elucidate the molecular mechanism underlying the capacity of the TAXI-III transgenic plants to limit FHB symptoms, we treated wheat tissues with the xylanase FGSG_03624, hitherto shown to induce cell death and hydrogen peroxide accumulation. Experiments performed on lemmas of flowering wheat spikes and wheat cell suspension cultures demonstrated that pre-incubation of xylanase FGSG_03624 with TAXI-III significantly decreased cell death. Most interestingly, a reduced cell death relative to control non-transgenic plants was also obtained by treating, with the same xylanase, lemmas of TAXI-III transgenic plants. Molecular modelling studies predicted an interaction between the TAXI-III residue H395 and residues E122 and E214 belonging to the active site of xylanase FGSG_03624. These results provide, for the first time, clear indications in vitro and in planta that a xylanase inhibitor can prevent the necrotic activity of a xylanase, and suggest that the reduced FHB symptoms on transgenic TAXI-III plants may be a result not only of the direct inhibition of xylanase activity secreted by the pathogen, but also of the capacity of TAXI-III to avoid host cell death. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  10. Discrepancy analysis of driving performance of taxi drivers and non-professional drivers for red-light running violation and crash avoidance at intersections.

    PubMed

    Wu, Jiawei; Yan, Xuedong; Radwan, Essam

    2016-06-01

    Due to comfort, convenience, and flexibility, taxis have become increasingly more prevalent in China, especially in large cities. However, many violations and road crashes that occurred frequently were related to taxi drivers. This study aimed to investigate differences in driving performance between taxi drivers and non-professional drivers from the perspectives of red-light running violation and potential crash involvement based on a driving simulation experiment. Two typical scenarios were established in a driving simulator, which includes the red-light running violation scenario and the crash avoidance scenario. There were 49 participants, including 23 taxi drivers (14 males and 9 females) and 26 non-professional drivers (13 males and 13 females) recruited for this experiment. The driving simulation experiment results indicated that non-professional drivers paid more attention to red-light running violations in comparison to taxi drivers who had a higher probability of red-light running violation. Furthermore, it was found that taxi drivers were more inclined to turn the steering wheel in an attempt to avoid a potential collision and non-professional drivers had more abrupt deceleration behaviors when facing a potential crash. Moreover, the experiment results showed that taxi drivers had a smaller crash rate compared to non-professional drivers and had a better performance in terms of crash avoidance at the intersection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. The prevalence of fatigue and associated health and safety risk factors among taxi drivers in Singapore

    PubMed Central

    Lim, See Ming; Chia, Sin Eng

    2015-01-01

    INTRODUCTION Driver fatigue is one of the biggest health and safety concerns within the road transport sector. This study aimed to determine the prevalence of fatigue among taxi drivers in Singapore, to better understand the general working and health conditions of this group of people, and to determine the risk factors associated with fatigued driving. METHODS A total of 340 taxi drivers were randomly selected for participation in a self-administered questionnaire survey, which included height and weight measurements. The response rate was 68.2%. The survey consisted of four main categories: personal particulars; social habits; work patterns; and sleep profile. The Epworth Sleepiness Scale was used to estimate the level of daytime sleepiness and fatigue. Multiple logistic regression analysis was used to estimate the adjusted odd ratios and 95% confidence intervals associated with risk factors related to fatigue among taxi drivers. RESULTS A high proportion of taxi drivers were obese and had self-reported hypertension, diabetes mellitus and high cholesterol. Driver fatigue was associated with very poor/poor self-rating of quality of sleep, having an additional part-time job, drinking three or more caffeinated drinks daily, and driving more than 10 hours a day. CONCLUSION We hope that the findings of the present study will improve awareness of the work and health conditions of taxi drivers, and contribute toward efforts to achieve a healthier workforce. A lower prevalence of fatigued driving may lead to lower risks of road traffic accidents, decreased economic loss, increased productivity, and safer roads for all. PMID:25532512

  12. The prevalence of fatigue and associated health and safety risk factors among taxi drivers in Singapore.

    PubMed

    Lim, See Ming; Chia, Sin Eng

    2015-02-01

    Driver fatigue is one of the biggest health and safety concerns within the road transport sector. This study aimed to find out the prevalence of fatigue among taxi drivers in Singapore, to better understand the general working and health conditions of this group of people and to determine the risk factors associated with fatigued driving. A total of 340 taxi drivers were randomly selected for participation in this self-administered questionnaire survey, with height and weight measurements. The response rate was 68.2%. The survey consisted of four main categories: personal particulars; social habits; work patterns and sleep profile; and Epworth Sleepiness Scale, which was used to estimate the level of daytime sleepiness and fatigue. Multiple logistic regression analysis was used to estimate the adjusted odd ratios and 95% confidence intervals associated with the risk factors related to fatigue among the taxi drivers. A high proportion of the taxi drivers were obese and had self-reported hypertension, diabetes mellitus and high cholesterol. Driver fatigue was associated with very poor/poor self-rating of the quality of sleep, having an additional part-time job, drinking three or more caffeinated drinks daily, and driving more than 10 hours a day. We hope that the findings of the present study will improve the awareness regarding the work and health conditions of taxi drivers, and contribute toward the effort to achieve a healthier workforce. A lower prevalence of fatigued driving will lead to lower risks of road traffic accidents, decreased economic loss, increased productivity, and safer roads for all.

  13. Compliance and enforcement of a partial smoking ban in Lisbon taxis: an exploratory cross-sectional study

    PubMed Central

    2013-01-01

    Background Research evaluating enforcement and compliance with smoking partial bans is rather scarce, especially in countries with relative weak tobacco control policies, such as Portugal. There is also scarce evidence on specific high risk groups such as vehicle workers. In January 2008, Portugal implemented a partial ban, followed by poor enforcement. The purpose of this study was to explore the effectiveness of a partial smoking ban in a pro-smoking environment, specifically transportation by taxi in the city of Lisbon. Ban effectiveness was generally defined by ban awareness and support, compliance and enforcement. Methods Exploratory cross-sectional study; purposive sampling in selected Lisbon streets. Structured interviews were conducted by trained researchers while using taxi services (January 2009-December 2010). Participants: 250 taxi drivers (98.8% participation rate). Chi-square, McNemar, Man Whitney tests and multiple logistic regression were performed. Results Of the participants, 249 were male; median age was 53.0 years; 43.6% were current smokers. Most participants (82.8%) approved comprehensive bans; 84.8% reported that clients still asked to smoke in their taxis; 16.8% allowed clients to smoke. Prior to the ban this value was 76.9% (p < 0.001). The major reason for not allowing smoking was the legal ban and associated fines (71.2%). Of the smokers, 66.1% admitted smoking in their taxi. Stale smoke smells were detected in 37.6% of the cars. None of the taxi drivers did ever receive a fine for non-compliance. Heavy smoking, night-shift and allowing smoking prior the ban predicted non-compliance. Conclusions Despite the strong ban support observed, high smoking prevalence and poor enforcement contribute to low compliance. The findings also suggest low compliance among night-shift and vehicle workers. This study clearly demonstrates that a partial and poorly-enforced ban is vulnerable to breaches, and highlights the need for clear and strong

  14. Taxi Regulatory Revision in San Diego, California : Background and Implementation

    DOT National Transportation Integrated Search

    1981-07-01

    Starting in January, 1979, the San Diego City Council revised its paratransit regulations and began issuing 6 new taxi permits per month. As of July, 1979, the ratio of new permit issuance was increased to 15 per month. Effective August 1, 1979, the ...

  15. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Taxi, takeoff and landing roll. 25.491..., takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane structure and landing gear are assumed to be subjected to loads not less than those obtained when the...

  16. 14 CFR 25.491 - Taxi, takeoff and landing roll.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Taxi, takeoff and landing roll. 25.491..., takeoff and landing roll. Within the range of appropriate ground speeds and approved weights, the airplane structure and landing gear are assumed to be subjected to loads not less than those obtained when the...

  17. Labeling Residential Community Characteristics from Collective Activity Patterns Using Taxi Trip Data

    NASA Astrophysics Data System (ADS)

    Zhou, Y.; Fang, Z.

    2017-09-01

    There existing a significant social and spatial differentiation in the residential communities in urban city. People live in different places have different socioeconomic background, resulting in various geographically activity patterns. This paper aims to label the characteristics of residential communities in a city using collective activity patterns derived from taxi trip data. Specifically, we first present a method to allocate the O/D (Origin/Destination) points of taxi trips to the land use parcels where the activities taken place in. Then several indices are employed to describe the collective activity patterns, including both activity intensity, travel distance, travel time, and activity space of residents by taking account of the geographical distribution of all O/Ds of the taxi trip related to that residential community. Followed by that, an agglomerative hierarchical clustering algorithm is introduced to cluster the residential communities with similar activity patterns. In the case study of Wuhan, the residential communities are clearly divided into eight clusters, which could be labelled as ordinary communities, privileged communities, old isolated communities, suburban communities, and so on. In this paper, we provide a new perspective to label the land use under same type from people's mobility patterns with the support of big trajectory data.

  18. Fuel Consumption and Emissions from Airport Taxi Operations

    NASA Technical Reports Server (NTRS)

    Jung, Yoon

    2010-01-01

    Developed a method to calculate fuel consumption and emissions of phases of taxi operations. Results at DFW showed that up to 18% of fuel can be saved by eliminating stop-and-go situations. Developed an energy efficient and environmentally friendly surface concept: Spot and Runway Departure Advisory (SARDA) tool. The SARDA tool has been identified as a potential candidate for a technology transfer to the FAA.

  19. Design Reference Missions (DRM): Integrated ODM 'Air-Taxi' Mission Features

    NASA Technical Reports Server (NTRS)

    Kloesel, Kurt; Starr, Ginn; Saltzman, John A.

    2017-01-01

    Design Reference Missions (DRM): Integrated ODM Air-Taxi Mission Features, Hybrid Electric Integrated System Testbed (HEIST) flight control. Structural Health, Energy Storage, Electric Components, Loss of Control, Degraded Systems, System Health, Real-Time IO Operator Geo-Fencing, Regional Noise Abatement and Trusted Autonomy Inter-operability.

  20. Environmental factors associated with crash-related mortality and injury among taxi drivers in New South Wales, Australia.

    PubMed

    Lam, Lawrence T

    2004-09-01

    This exploratory study aims to investigate the associations between some environmental factors and the increased risk of motor vehicle crash-related injuries among taxi drivers. Information utilised in the study are obtained from police reports of all road traffic accidents that occurred on the roads between 1996 and 2000 in New South Wales (NSW), Australia. Of the 7923 taxi drivers who involved in crashes, nearly 10% (n = 750) were killed or injured. Results indicate sex, and two environmental factors are significantly associated with an increased risk of crash-related mortality and injury among taxi drivers. The adjusted relative risk of crash-related mortality and injury is increased by 60% for those who work the night shift (OR = 1.59, 95%CI = 1.35-1.88), and by 20% for those who do not carry any passenger on board (OR = 1.20, 95%CI = 1.02-1.41) should these drivers involve in a crash. The increased relative risk of crash-related mortality and injury is nearly 2.5 times for female taxi drivers (OR = 2.30, 95%CI = 1.45-3.65) when compared with their male counterparts. Copyright 2003 Elsevier Ltd.

  1. Taxi driver speeding: Who, when, where and how? A comparative study between Shanghai and New York City.

    PubMed

    Huang, Yizhe; Sun, Daniel Jian; Tang, Juanyu

    2018-04-03

    The 3 objectives of this study are to (1) identify the driving style characteristics of taxi drivers in Shanghai and New York City (NYC) using taxi Global Positioning System (GPS) data and make a comparative analysis; (2) explore the influence of different driving style characteristics on the frequency of speeding (who and how?) and (3) explore the influence of driving style characteristics, road attributes, and environmental factors on the speeding rate (when, where, and how?) Methods: This study proposes a driver-road-environment identification (DREI) method to investigate the determinant factors of taxi speeding violations. Driving style characteristics, together with road and environment variables, were obtained based on the GPS data and auxiliary spatiotemporal data in Shanghai and NYC. The daily working hours of taxi drivers in Shanghai (18.6 h) was far more than in NYC (8.5 h). The average occupancy speed of taxi drivers in Shanghai (21.3 km/h) was similar to that of NYC (20.3 km/h). Speeders in both cities had shorter working hours and longer daily driving distance than other taxi drivers, though their daily income was similar. Speeding drivers routinely took long-distance trips (>10 km) and preferred relatively faster routes. Length of segments (1.0-1.5 km) and good traffic condition were associated with high speeding rates, whereas central business district area and secondary road were associated with low speeding rates. Moreover, many speeding violations were identified between 4:00 a.m. and 7:00 a.m. in both Shanghai and NYC and the worst period was between 5:00 a.m. and 6:00 a.m. in both cities. Characteristics of drivers, road attributes, and environment variables should be considered together when studying driver speeding behavior. Findings of this study may assist in stipulating relevant laws and regulations such as stricter offense monitoring in the early morning, long segment supervision, shift rule regulation, and working hour restriction to

  2. Turing-Hopf bifurcations in a predator-prey model with herd behavior, quadratic mortality and prey-taxis

    NASA Astrophysics Data System (ADS)

    Liu, Xia; Zhang, Tonghua; Meng, Xinzhu; Zhang, Tongqian

    2018-04-01

    In this paper, we propose a predator-prey model with herd behavior and prey-taxis. Then, we analyze the stability and bifurcation of the positive equilibrium of the model subject to the homogeneous Neumann boundary condition. By using an abstract bifurcation theory and taking prey-tactic sensitivity coefficient as the bifurcation parameter, we obtain a branch of stable nonconstant solutions bifurcating from the positive equilibrium. Our results show that prey-taxis can yield the occurrence of spatial patterns.

  3. Taxi Regulatory Revision in Oakland and Berkeley, California : Two Case Studies

    DOT National Transportation Integrated Search

    1983-06-01

    A case study was performed of regulatory changes pertaining to taxicabs in Oakland and neighboring Berkeley, CA. In Oakland rates were approximately doubled and limits on the number of taxi permits removed. Companies were allowed to levy a per-trip s...

  4. Visual exploration of big spatio-temporal urban data: a study of New York City taxi trips.

    PubMed

    Ferreira, Nivan; Poco, Jorge; Vo, Huy T; Freire, Juliana; Silva, Cláudio T

    2013-12-01

    As increasing volumes of urban data are captured and become available, new opportunities arise for data-driven analysis that can lead to improvements in the lives of citizens through evidence-based decision making and policies. In this paper, we focus on a particularly important urban data set: taxi trips. Taxis are valuable sensors and information associated with taxi trips can provide unprecedented insight into many different aspects of city life, from economic activity and human behavior to mobility patterns. But analyzing these data presents many challenges. The data are complex, containing geographical and temporal components in addition to multiple variables associated with each trip. Consequently, it is hard to specify exploratory queries and to perform comparative analyses (e.g., compare different regions over time). This problem is compounded due to the size of the data-there are on average 500,000 taxi trips each day in NYC. We propose a new model that allows users to visually query taxi trips. Besides standard analytics queries, the model supports origin-destination queries that enable the study of mobility across the city. We show that this model is able to express a wide range of spatio-temporal queries, and it is also flexible in that not only can queries be composed but also different aggregations and visual representations can be applied, allowing users to explore and compare results. We have built a scalable system that implements this model which supports interactive response times; makes use of an adaptive level-of-detail rendering strategy to generate clutter-free visualization for large results; and shows hidden details to the users in a summary through the use of overlay heat maps. We present a series of case studies motivated by traffic engineers and economists that show how our model and system enable domain experts to perform tasks that were previously unattainable for them.

  5. 14 CFR 298.21 - Filing for registration by air taxi operators.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ambulance operations, firefighting or seasonal operations); 7 Companies proposing to provide scheduled... conduct such operations under their air taxi registration; such companies must first be found fit, willing... Region Headquarters (AAL-230), 222 West 7th Avenue, Box 14, Anchorage, Alaska 99513. ...

  6. Occupational and Personal Determinants of Musculoskeletal Disorders among Urban Taxi Drivers in Ghana

    PubMed Central

    Abledu, J. K.; Offei, E. B.; Abledu, G. K.

    2014-01-01

    Background. There is a lack of epidemiological data on musculoskeletal disorders (MSDs) among occupational drivers in Ghana. The present study seeks to estimate the prevalence, body distribution, and occupational and personal determinants of MSDs in a sample of taxi drivers in the Accra Metropolis of Ghana. Methods. A total of 210 participants were enrolled in this cross-sectional study. All the participants were evaluated by using a semistructured questionnaire and the standardized Nordic Musculoskeletal Disorder Questionnaire. Results. The estimated prevalence of MSDs was 70.5%. The prevalence of the various MSD domains was as follows: lower back pain (34.3%), upper back pain (16.7%), neck pain (15.2%), shoulder pain (11.0%), knee pain (10.0%), hip/thigh pain (2.9%), elbow pain (4.8%), ankle/feet pain (2.4%), and wrist/hand pain (1.9%). Multiple logistic regression analysis of the data showed that participants who were employee drivers, drove taxi more than 12 hours per day or at least 5 days per week, perceived their job as stressful, and were dissatisfied with their job were at a greater risk of developing MSDs. Conclusions. These findings call for preventive strategies and safety guidelines in order to reduce the incidence of MSDs among urban taxi drivers in Ghana. PMID:27379297

  7. Health status, job stress and work-related injury among Los Angeles taxi drivers.

    PubMed

    Wang, Pin-Chieh; Delp, Linda

    2014-01-01

    Taxi drivers work long hours for low wages and report hypertension, weight gain, and musculoskeletal pain associated with the sedentary nature of their job, stressful working conditions, and poor dietary habits. They also experience a high work-related fatality rate. The objective of this study is to examine the association of taxi drivers' health status and level of job stress with work-related injury and determine if a potential interaction exists. A survey of 309 Los Angeles taxi drivers provides basic data on health status, job stress, and work-related injuries. We further analyzed the data using a Modified Poisson regression approach with a robust error variance to estimate the relative risk (RR) and the 95% confidence intervals (CI) of work-related injuries. Focus group results supplemented and helped interpret the quantitative data. The joint effect of good health and low job stress was associated with a large reduction in the incidence of injuries, consistent with the hypothesis that health status and stress levels modify each other on the risk of work-related injury. These results suggest that the combination of stress reduction and health management programs together with changes in the stressful conditions of the job may provide targeted avenues to prevent injuries.

  8. Occupational and Personal Determinants of Musculoskeletal Disorders among Urban Taxi Drivers in Ghana.

    PubMed

    Abledu, J K; Offei, E B; Abledu, G K

    2014-01-01

    Background. There is a lack of epidemiological data on musculoskeletal disorders (MSDs) among occupational drivers in Ghana. The present study seeks to estimate the prevalence, body distribution, and occupational and personal determinants of MSDs in a sample of taxi drivers in the Accra Metropolis of Ghana. Methods. A total of 210 participants were enrolled in this cross-sectional study. All the participants were evaluated by using a semistructured questionnaire and the standardized Nordic Musculoskeletal Disorder Questionnaire. Results. The estimated prevalence of MSDs was 70.5%. The prevalence of the various MSD domains was as follows: lower back pain (34.3%), upper back pain (16.7%), neck pain (15.2%), shoulder pain (11.0%), knee pain (10.0%), hip/thigh pain (2.9%), elbow pain (4.8%), ankle/feet pain (2.4%), and wrist/hand pain (1.9%). Multiple logistic regression analysis of the data showed that participants who were employee drivers, drove taxi more than 12 hours per day or at least 5 days per week, perceived their job as stressful, and were dissatisfied with their job were at a greater risk of developing MSDs. Conclusions. These findings call for preventive strategies and safety guidelines in order to reduce the incidence of MSDs among urban taxi drivers in Ghana.

  9. A lightweight neighbor-info-based routing protocol for no-base-station taxi-call system.

    PubMed

    Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

    2014-01-01

    Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene.

  10. Small City Transit : El Cajon, California : City-Wide Shared-Ride Taxi Service

    DOT National Transportation Integrated Search

    1976-03-01

    El Cajon, California, is an illustration of a shared ride taxi service. This case study is one of thirteen examples of a transit service in a small community. The background of the community is discussed along with a description of the implementation...

  11. Training and Proficiency Testing for Commuter and Air Taxi Pilots - Federal Aviation Administration

    DOT National Transportation Integrated Search

    1996-10-21

    The objective of this audit was to determine whether the Federal Aviation : Administration (FAA) has established procedures and oversight controls to assure : that commuter and air taxi pilots, engaged in passenger-carrying operations, : hold valid p...

  12. Potential for Flexicab Services : Innovative Uses of Taxis and Jitneys for Public Transportation

    DOT National Transportation Integrated Search

    1975-12-01

    Taxis and jitneys can be significant urban transportation resource. Used innovatively to provide public transit services, they can offer mobility in low density areas where mass transit is not feasible, supplement mass transit economically to improve...

  13. Factors related to pilot survival in helicopter commuter and air taxi crashes.

    PubMed

    Krebs, M B; Li, G; Baker, S P

    1995-02-01

    We examined factors related to pilot survival in 167 consecutive helicopter commuter and air taxi crashes that occurred during 1983-88. Case fatality rates and adjusted odds ratios from multivariate logistic regression models were determined using data from the National Transportation Safety Board (NTSB). During this 6-year period, 29 pilots-in-command died in 167 helicopter commuter and air taxi crashes, a case fatality rate of 17.4%. Factors significantly associated with increased risk of pilot fatality were aircraft fire [odds ratio (OR) 20.0, 95% confidence interval (CI) 4.6-86.8], not using shoulder harnesses (OR 9.2, 95% CI 2.2-37.3), and aircraft with two engines (OR 4.8, 95% CI 1.3-17.4). In addition, we present data regarding success and failure of emergency flotation devices. The results suggest that the likelihood of pilot survival in helicopter crashes could be greatly improved by preventing crash associated fires and promoting the usage of shoulder restraints.

  14. XB-70A during startup and ramp taxi

    NASA Technical Reports Server (NTRS)

    1968-01-01

    The XB-70 was the world's largest experimental aircraft. Capable of flight at speeds of three times the speed of sound (2,000 miles per hour) at altitudes of 70,000 feet, the XB-70 was used to collect in-flight information for use in the design of future supersonic aircraft, military and civilian. This 35-second video shows the startup of the XB-70A airplane engines, the beginning of its taxi to the runway, and a turn on the ramp that shows the unique configuration of this aircraft.

  15. Alternative Fuels Data Center: Happy Cab Fuels Taxi Fleet With CNG

    Science.gov Websites

    Happy Cab Fuels Taxi Fleet With CNG Find out how a cab company in Omaha, Nebraska, saves money fueling Go Electric in Florida Feb. 15, 2014 Renzenberger Inc Saves Money With Propane Vans Feb. 1, 2014 Gas School Buses Help Kansas City Save Money Nov. 12, 2011 Metropolitan Utilities District Fuels

  16. Alternative Fuels Data Center: Yellow Cab Converts Taxis to Propane in

    Science.gov Websites

    electric car. College Students Engineer Efficient Vehicles in EcoCAR 2 Competition Aug. 2, 2014 Photo of a Columbus, OhioA> Yellow Cab Converts Taxis to Propane in Columbus, Ohio to someone by E-mail how Yellow Cab is overhauling their fleet in Columbus, Ohio, with propane power. For information about

  17. Evaluation of a full-time ride service program : Aspen, Colorado's Tipsy Taxi service

    DOT National Transportation Integrated Search

    2000-10-01

    This report summarizes a study of Aspen, Colorado's Tipsy Taxi ride service program. This service, which provides a free ride home for persons who are too intoxicated to drive, has been in place since December 1983. Funded through donations from the ...

  18. 41 CFR 301-10.421 - How much will my agency reimburse me for a tip to a taxi, shuttle service, or courtesy...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 4 2011-07-01 2011-07-01 false How much will my agency reimburse me for a tip to a taxi, shuttle service, or courtesy transportation driver? 301-10.421 Section 301... tip to a taxi, shuttle service, or courtesy transportation driver? An amount which your agency...

  19. 41 CFR 301-10.421 - How much will my agency reimburse me for a tip to a taxi, shuttle service, or courtesy...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false How much will my agency reimburse me for a tip to a taxi, shuttle service, or courtesy transportation driver? 301-10.421 Section 301... tip to a taxi, shuttle service, or courtesy transportation driver? An amount which your agency...

  20. Impulsivity and risky decision making among taxi drivers in Hong Kong: An event-related potential study.

    PubMed

    Cheng, Andy S K; Ting, K H; Liu, Karen P Y; Ba, Yutao

    2016-10-01

    Taxi drivers play an important role in providing safe and professional public transport services. However, they tend to be more involved than other professional driver groups in accidents caused by deliberate recklessness. This study used an event-related potential (ERP) experiment to examine risk-taking behavior arising from impulsivity by comparing the underlying neural processes of taxi drivers with and without traffic offence records in Hong Kong. A sample of 15 traffic offenders and 15 nonoffenders, matched by sociodemographic characteristics, was recruited. The results show that the offender group demonstrated significantly less negative-going (less negative) feedback-related negativity but more positive-going (more positive) feedback-related P300 when than with their nonoffending counterparts. These findings show that taxi drivers with traffic offence records were less sensitive to the consequences of behavior and more attuned to the magnitude of potential reward. In addition, behavioral data revealed that they were more willing to make risky decisions. All these characteristics pertain to impulsive personality traits. Based on these findings, we can conclude that the offenders in this sample were more impulsive than their nonoffending counterparts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Estimate of air carrier and air taxi crash frequencies from high altitude en route flight operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanzo, D.; Kimura, C.Y.; Prassinos, P.G.

    1996-06-03

    In estimating the frequency of an aircraft crashing into a facility, it has been found convenient to break the problem down into two broad categories. One category estimates the aircraft crash frequency due to air traffic from nearby airports, the so-called near-airport environment. The other category estimates the aircraft crash frequency onto facilities due to air traffic from airways, jet routes, and other traffic flying outside the near-airport environment The total aircraft crash frequency is the summation of the crash frequencies from each airport near the facility under evaluation and from all airways, jet routes, and other traffic near themore » facility of interest. This paper will examine the problems associated with the determining the aircraft crash frequencies onto facilities outside the near-airport environment. This paper will further concentrate on the estimating the risk of aircraft crashes to ground facilities due to high altitude air carrier and air taxi traffic. High altitude air carrier and air taxi traffic will be defined as all air carrier and air taxi flights above 18,000 feet Mean Sea Level (MSL).« less

  2. User-Side Subsidies for Shared Ride Taxi Service in Danville, Illinois : Phase 1.

    DOT National Transportation Integrated Search

    1977-06-01

    An UMTA Service and Methods Demonstration has been implemented in Danville, Illinois. The Purpose of the Demonstration is to test the use of a user-side subsidy on a shared ride taxi service for handicapped and elderly persons. This report presents t...

  3. Ambulatory heart rate of professional taxi drivers while driving without their typical psychosocial work stressors: a pilot study.

    PubMed

    Choi, BongKyoo; Choi, SangJun; Jeong, JeeYeon; Lee, JiWon; Shu, Shi; Yu, Nu; Ko, SangBaek; Zhu, Yifang

    2016-01-01

    Few studies have examined ambulatory cardiovascular physiological parameters of taxi drivers while driving in relation to their occupational hazards. This study aims to investigate and quantify the impact of worksite physical hazards as a whole on ambulatory heart rate of professional taxi drivers while driving without their typical worksite psychosocial stressors. Ambulatory heart rate (HR driving ) of 13 non-smoking male taxi drivers (24 to 67 years old) while driving was continuously assessed on their 6-hour experimental on-road driving in Los Angeles. Percent maximum HR range (PMHR driving ) of the drivers while driving was estimated based on the individual HR driving values and US adult population resting HR (HR rest ) reference data. For analyses, the HR driving and PMHR driving data were split and averaged into 5-min segments. Five physical hazards inside taxi cabs were also monitored while driving. Work stress and work hours on typical work days were self-reported. The means of the ambulatory 5-min HR driving and PMHR driving values of the 13 drivers were 80.5 bpm (11.2 bpm higher than their mean HR rest ) and 10.7 % (range, 5.7 to 19.9 %), respectively. The means were lower than the upper limits of ambulatory HR and PMHR for a sustainable 8-hour work (35 bpm above HR rest and 30 % PMHR), although 15-27 % of the 5-min HR driving and PMHR driving values of one driver were higher than the limits. The levels of the five physical hazards among the drivers were modest: temperature (26.4 ± 3.0 °C), relative humidity (40.7 ± 10.4 %), PM 2.5 (21.5 ± 7.9  μg /m 3 ), CO 2 (1,267.1 ± 580.0 ppm) and noise (69.7 ± 3.0 dBA). The drivers worked, on average, 72 h per week and more than half of them reported that their job were often stressful. The impact of physical worksite hazards alone on ambulatory HR of professional taxi drivers in Los Angeles generally appeared to be minor. Future ambulatory heart rate studies including both

  4. 14 CFR Appendix C to Part 330 - Forms for Air Taxi Operators

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Forms for Air Taxi Operators C Appendix C to Part 330 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) PROCEDURAL REGULATIONS PROCEDURES FOR COMPENSATION OF AIR CARRIERS Pt. 330, App. C Appendix C to...

  5. Relation between workplace accidents and the levels of carboxyhemoglobin in motorcycle taxi drivers.

    PubMed

    da Silva, Luiz Almeida; Robazzi, Maria Lúcia do Carmo Cruz; Terra, Fábio de Souza

    2013-01-01

    To investigate the relation between workplace accidents and the levels of carboxyhemoglobin found in motorcycle taxi drivers. Correlational, quantitative study involving 111 workers and data obtained in July 2012 through a questionnaire to characterize the participants and blood collection to measure carboxyhemoglobin levels. 28.8% had suffered workplace accidents; 27.6% had fractured the lower limbs and significant symptoms of carbon monoxide exposure were verified in smokers. The carboxyhemoglobin levels were higher among smokers and victims of workplace accidents. Motorcycle taxi drivers had increased levels of carboxyhemoglobin, possibly due to the exposure to carbon monoxide; these levels are also increased among smokers and victims of workplace accidents. The study provides advances in the knowledge about occupational health and environmental science, and also shows that carboxyhemoglobin can be an indicator of exposure to environmental pollutants for those working outdoors, which can be related to workplace accidents.

  6. Prediction of safe driving Behaviours based on health belief model: the case of taxi drivers in Bandar Abbas, Iran.

    PubMed

    Razmara, Asghar; Aghamolaei, Teamur; Madani, Abdoulhossain; Hosseini, Zahra; Zare, Shahram

    2018-03-20

    Road accidents are among the main causes of mortality. As safe and secure driving is a key strategy to reduce car injuries and offenses, the present research aimed to explore safe driving behaviours among taxi drivers based on the Health Belief Model (HBM). This study was conducted on 184 taxi drivers in Bandar Abbas who were selected based on a multiple stratified sampling method. Data were collected by a questionnaire comprised of a demographic information section along with the constructs of the HBM. Data were analysed by SPSS ver19 via a Pearson's correlation coefficient and multiple regressions. The mean age of the participants was 45.1 years (SD = 11.1). They all had, on average, 10.3 (SD = 7/5) years of taxi driving experience. Among the HBM components, cues to action and perceived benefits were shown to be positively correlated with safe driving behaviours, while perceived barriers were negatively correlated. Cues to action, perceived barriers and perceived benefits were shown to be the strongest predictors of a safe drivers' behaviour. Based on the results of this study in designing health promotion programmes to improve safe driving behaviours among taxi drivers, cues to action, perceived benefits and perceived barriers are important. Therefore, advertising, the design of information campaigns, emphasis on the benefits of safe driving behaviours and modification barriers are recommended.

  7. Subsidized Taxi Programs for Elderly and Handicapped Persons in the San Francisco Bay Area

    DOT National Transportation Integrated Search

    1977-09-01

    The report examines subsidized taxi systems serving elderly and handicapped persons in six locations in the San Francisco Bay Area. The systems studied are San Leandro, Santa Clara County, Sunnyvale, Palo Alto, Lafayette, and Fremont. These systems a...

  8. Exposure of Paris taxi drivers to automobile air pollutants within their vehicles

    PubMed Central

    Zagury, E.; Le Moullec, Y.; Momas, I.

    2000-01-01

    OBJECTIVES—To study the exposure of Parisian taxi drivers to automobile air pollutants during their professional activity.
METHODS—A cross sectional study was carried out from 27 January to 27 March 1997, with measurements performed in the vehicles of 29 randomly selected drivers. Carbon monoxide (CO) content was measured over an 8 hour period by a CO portable monitor. The fine suspended particles were measured according to the black smoke index (BS), with a flow controlled portable pump provided with a cellulose filter. The nitrogen oxides, NO and NO2 were measured with a passive sampler.
RESULTS—These drivers are exposed during their professional activity to relatively high concentrations of pollutants (mean, median (SD) 3.8, 2 (1.7) ppm for CO, 168, 164 (53) µg/m3 for BS, 625, 598 (224) µg/m3 for NO, and 139, 131 (43) µg/m3 for NO2.) For CO the concentrations were clearly lower than the threshold values recommended by the World Health Organisation. The situation is less satisfactory for the other pollutants, especially for the BS index. All concentrations of pollutants recorded were noticeably higher than concentrations in air recorded by the ambient Parisian air monitoring network and were close to, or slightly exceeded, the concentrations measured at the fixed stations close to automobile traffic. Pollutant concentrations were also influenced greatly by weather conditions.
CONCLUSION—This first French study conducted in taxi drivers shows that they are highly exposed to automobile pollutants. The results would justify a medical follow up of this occupational group.


Keywords: taxi drivers; exposure assessment PMID:10810130

  9. Sitting on the runway : current aircraft taxi times now exceed pre-9/11 experience

    DOT National Transportation Integrated Search

    2008-05-01

    Several high profi le incidents have focused attention on : tarmac delays that resulted in air travelers spending long : periods of time aboard aircraft waiting to either take off or : move to a gate after landing. Taxi-time data collected by :...

  10. “Every disease…man can get can start in this cab”: Focus groups to identify South Asian taxi drivers’ knowledge, attitudes and beliefs about cardiovascular disease and its risks

    PubMed Central

    Gany, Francesca M; Gill, Pavan P; Ahmed, Ayaz; Acharya, Sudha; Leng, Jennifer

    2017-01-01

    Background South Asian (SA) taxi drivers potentially possess a double epidemiologic risk for cardiovascular disease (CVD) due to their ethnicity and occupation. This study investigates SA taxi drivers’ knowledge, attitudes, beliefs about general health, CVD and approaches to reduce CVD risk. Method Five focus groups were conducted with 31 SA taxi drivers in the participants’ primary language (Bengali, Hindi, Urdu or Punjabi). Audio-recordings of the sessions were transcribed, translated and entered into ATLAS.ti 6.2 for coding and analysis. Results SA drivers in an urban setting perceive themselves to be at high risk for CVD because of high work-related stress, physical inactivity, poor diet and poor health care access. Participants attributed their occupation to increasing risk for heart disease; none believed that being SA increased their risk. Discussion Interventions to lower CVD risk among SA taxi drivers should be multi-level and involve the individual drivers and the taxi industry. PMID:22843321

  11. Taking actions to quit chewing betel nuts and starting a new life: taxi drivers' successful experiences of quitting betel nut chewing.

    PubMed

    Yang, Tsui-Yun; Lin, Hung-Ru

    2017-04-01

    To understand taxi drivers' successful experiences of quitting betel nut chewing. Previous studies verified that betel nut chewing significantly increases the risk of oral cancer. In Taiwan, taxi drivers work for approximately 10-13 hours per day, and 31·7-80% of them choose to chew betel nuts for their invigorating qualities, which enable them to work more hours and receive more income. A qualitative research design was used. This study used the grounded theory method with purposive sampling to perform in-depth interviews with male taxi drivers who had successfully quit betel nut chewing for more than six months. The interviewed participants were 25 taxi drivers aged 45-67 who had chewed betel nuts for an average of 30·9 years. A constant comparative analysis of the 25 interviews revealed six categories, namely the first experience of chewing betel nuts, a part of work and life, perceiving the impact of betel nuts, trying to change, acting to quit betel nut chewing and starting a new life. During the cessation process, taxi drivers tended to be affected by their addiction to chewing betel nuts and the temptation of friends' invitations to chew betel nuts. However, their recognition of the physical effects of betel nut chewing and their sense of responsibility and commitment to family were the critical factors affecting their determination to quit betel nut chewing. Their willpower to not to chew betel nuts and the source of their motivation to exercise self-control also contributed to their success. Healthcare personnel should understand the experiences and perceptions of betel nut chewers, strengthen their understanding of the effects of betel nut chewing on physical health during the cessation period and support their self-efficacy and quitting behaviours with the assistance of significant others. © 2016 John Wiley & Sons Ltd.

  12. Perception and reality of particulate matter exposure in New York City taxi drivers

    PubMed Central

    Gany, Francesca; Bari, Sehrish; Prasad, Lakshmi; Leng, Jennifer; Lee, Trevor; Thurston, George D; Gordon, Terry; Acharya, Sudha; Zelikoff, Judith T

    2017-01-01

    Background Exposure to fine particulate matter (PM2.5) and black carbon (BC) have been linked to negative health risks, but exposure among professional taxi drivers is unknown. This study measured drivers' knowledge, attitudes, and beliefs (KAB) about air pollution compared to direct measures of exposures. Methods Roadside and in-vehicle levels of PM2.5 and BC were continuously measured over a single shift and compared to central site monitoring. Participants completed an air pollution KAB questionnaire. Results Taxicab PM2.5 and BC concentrations were elevated compared to central monitoring. Average PM2.5 concentrations per 15-minute interval were 4 - 49 μg/m3; 1-minute peaks measured up to 452 μg/m3. BC levels were also elevated; reaching > 10 μg/m3. 56 of 100 drivers surveyed believed they were more exposed than non-drivers; 81 believed air pollution causes health problems. Conclusions Air pollution exposure among drivers likely exceeds EPA recommendations. Future studies should focus on reducing exposures and increasing awareness among taxi drivers. PMID:27168392

  13. The Effects of Very Light Jet Air Taxi Operations on Commercial Air Traffic

    NASA Technical Reports Server (NTRS)

    Smith, Jeremy C.; Dollyhigh, Samuel M.

    2006-01-01

    This study investigates the potential effects of Very Light Jet (VLJ) air taxi operations adding to delays experienced by commercial passenger air transportation in the year 2025. The affordable cost relative to existing business jets and ability to use many of the existing small, minimally equipped, but conveniently located airports is projected to stimulate a large demand for the aircraft. The resulting increase in air traffic operations will mainly be at smaller airports, but this study indicates that VLJs have the potential to increase further the pressure of demand at some medium and large airports, some of which are already operating at or near capacity at peak times. The additional delays to commercial passenger air transportation due to VLJ air taxi operations are obtained from simulation results using the Airspace Concepts Evaluation System (ACES) simulator. The direct increase in operating cost due to additional delays is estimated. VLJs will also cause an increase in traffic density, and this study shows increased potential for conflicts due to VLJ operations.

  14. Evaluation of aero commander propeller acoustic data: Taxi operations

    NASA Technical Reports Server (NTRS)

    Piersol, A. G.; Wilby, E. G.; Wilby, J. F.

    1979-01-01

    The acoustic data from ground tests performed on an Aero Commander propeller driven aircraft are analyzed. An array of microphones flush mounted on the side of the fuselage were used to record data. The propeller blade passage noise during operations at several different taxi speeds is considered and calculations of the magnitude and phase of the blade passage tones, the amplitude stability of the tones, and the spatial phase and coherence of the tones are included. The measured results are compared to theoretical predictions for propeller noise and various evaluations which reveal important details of propeller noise characteristics are presented.

  15. Optical tweezers for studying taxis in parasites

    NASA Astrophysics Data System (ADS)

    de Thomaz, A. A.; Fontes, A.; Stahl, C. V.; Pozzo, L. Y.; Ayres, D. C.; Almeida, D. B.; Farias, P. M. A.; Santos, B. S.; Santos-Mallet, J.; Gomes, S. A. O.; Giorgio, S.; Feder, D.; Cesar, C. L.

    2011-04-01

    In this work we present a methodology to measure force strengths and directions of living parasites with an optical tweezers setup. These measurements were used to study the parasites chemotaxis in real time. We observed behavior and measured the force of: (i) Leishmania amazonensis in the presence of two glucose gradients; (ii) Trypanosoma cruzi in the vicinity of the digestive system walls, and (iii) Trypanosoma rangeli in the vicinity of salivary glands as a function of distance. Our results clearly show a chemotactic behavior in every case. This methodology can be used to study any type of taxis, such as chemotaxis, osmotaxis, thermotaxis, phototaxis, of any kind of living microorganisms. These studies can help us to understand the microorganism sensory systems and their response function to these gradients.

  16. Perseus B Taxi Tests in Preparation for a New Series of Flight Tests

    NASA Image and Video Library

    1998-04-27

    The Perseus B remotely piloted aircraft taxis on the runway at Edwards Air Force Base, California, before a series of development flights at NASA's Dryden flight Research Center. The Perseus B is the latest of three versions of the Perseus design developed by Aurora Flight Sciences under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program.

  17. Advanced navigation aids in the flight deck : effects on ground taxi performance under low visibility conditions

    DOT National Transportation Integrated Search

    1996-01-01

    Reports the results of a part-task simulation evaluating the separate and combined effects of an electronic moving map display and newly developed HUD symbology on ground taxi performance, under moderate- and low-visibility conditions. Twenty-four co...

  18. Taxi drivers' views on risky driving behavior in Tehran: a qualitative study using a social marketing approach.

    PubMed

    Shams, Mohsen; Shojaeizadeh, Davoud; Majdzadeh, Reza; Rashidian, Arash; Montazeri, Ali

    2011-05-01

    The use of the social marketing approach for public health issues is increasing. This approach uses marketing concepts borrowed from the principles of commercial marketing to promote beneficial health behaviors. In this qualitative study, four focus groups involving 42 participants were used in consumer research to explore taxi drivers' views on the driving situation and the determinants of risky driving behaviors in Tehran, as well as to gather their ideas for developing a social marketing program to reduce risky driving behaviors among taxi drivers in Tehran, Iran. Participants were asked to respond to questions that would guide the development of a marketing mix, or four Ps (product, price, place and promotion). The discussions determined that the program product should involve avoiding risky driving behaviors through increased attention to driving. They pointed out that developing and communicating with a well-designed persuasive message meant to draw their attention to driving could affect their driving behaviors. In addition, participants identified price, place and promotion strategies. They offered suggestions for marketing nonrisky driving to the target audience. The focus group discussions generated important insights into the values and the motivations that affect consumers' decisions to adopt the product. The focus group guided the development of a social marketing program to reduce risky driving behaviors in taxi drivers in Tehran, Iran. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. TrajGraph: A Graph-Based Visual Analytics Approach to Studying Urban Network Centralities Using Taxi Trajectory Data.

    PubMed

    Huang, Xiaoke; Zhao, Ye; Yang, Jing; Zhang, Chong; Ma, Chao; Ye, Xinyue

    2016-01-01

    We propose TrajGraph, a new visual analytics method, for studying urban mobility patterns by integrating graph modeling and visual analysis with taxi trajectory data. A special graph is created to store and manifest real traffic information recorded by taxi trajectories over city streets. It conveys urban transportation dynamics which can be discovered by applying graph analysis algorithms. To support interactive, multiscale visual analytics, a graph partitioning algorithm is applied to create region-level graphs which have smaller size than the original street-level graph. Graph centralities, including Pagerank and betweenness, are computed to characterize the time-varying importance of different urban regions. The centralities are visualized by three coordinated views including a node-link graph view, a map view and a temporal information view. Users can interactively examine the importance of streets to discover and assess city traffic patterns. We have implemented a fully working prototype of this approach and evaluated it using massive taxi trajectories of Shenzhen, China. TrajGraph's capability in revealing the importance of city streets was evaluated by comparing the calculated centralities with the subjective evaluations from a group of drivers in Shenzhen. Feedback from a domain expert was collected. The effectiveness of the visual interface was evaluated through a formal user study. We also present several examples and a case study to demonstrate the usefulness of TrajGraph in urban transportation analysis.

  20. Aspergillus prevalence in air conditioning filters from vehicles: taxis for patient transportation, forklifts, and personal vehicles.

    PubMed

    Viegas, Carla; Moreira, Ricardo; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Viegas, Susana

    2018-05-04

    The frequency and importance of Aspergillus infections is increasing worldwide. This study aimed to assess the occupational exposure of forklifts and taxi drivers to Aspergillus spp. Nineteen filters from air conditioning system of taxis, 17 from forklifts and 37 from personal vehicles were assessed. Filters extract were streaked onto MEA, DG18 and in azole-supplemented media. Real-time quantitative PCR amplification of selected Aspergillus species-complex was also performed. Forklifts filter samples presented higher median values. Aspergillus section Nigri was the most observed in forklifts filters in MEA (28.2%) and in azole-supplemented media. DNA from Aspergillus sections Fumigati and Versicolores was successfully amplified by qPCR. This study enlightens the added value of using filters from the air conditioning system to assess Aspergillus spp. occupational exposure. Aspergillus azole resistance screening should be included in future occupational exposure assessments.

  1. Portraits of the Postmodern Person in "Taxi Driver,""Raging Bull," and "The King of Comedy."

    ERIC Educational Resources Information Center

    Mortimer, Barbara

    1997-01-01

    Argues that a postmodern theory of identity (i.e., the subject as coherent, integrated, discoverable self is a fiction of modernity) links Martin Scorsese's major films. Examines "Taxi Driver,""Raging Bull," and "King of Comedy." Concludes that these films articulate a major cultural shift and chronicle a…

  2. A Human Subject Evaluation of Airport Surface Situational Awareness Using Prototypical Flight Deck Electronic Taxi Chart Displays

    DOT National Transportation Integrated Search

    1995-11-01

    A study was conducted to test the effect on airport surface situational awareness of GPS derived position information : depicted on a prototypical electronic taxi chart display. The effect of position error and position uncertainty : symbology were a...

  3. Pseudomonas putida F1 uses energy taxis to sense hydroxycinnamic acids

    PubMed Central

    Hughes, Jonathan G.; Zhang, Xiangsheng; Parales, Juanito V.; Ditty, Jayna L.; Parales, Rebecca E.

    2017-01-01

    Soil bacteria such as pseudomonads are widely studied due to their diverse metabolic capabilities, particularly the ability to degrade both naturally occurring and xenobiotic aromatic compounds. Chemotaxis, the directed movement of cells in response to chemical gradients, is common in motile soil bacteria and the wide range of chemicals detected often mirrors the metabolic diversity observed. Pseudomonas putida F1 is a soil isolate capable of chemotaxis toward, and degradation of, numerous aromatic compounds. We showed that P. putida F1 is capable of degrading members of a class of naturally occurring aromatic compounds known as hydroxycinnamic acids, which are components of lignin and are ubiquitous in the soil environment. We also demonstrated the ability of P. putida F1 to sense three hydroxycinnamic acids: p-coumaric, caffeic and ferulic acids. The chemotaxis response to hydroxycinnamic acids was induced during growth in the presence of hydroxycinnamic acids and was negatively regulated by HcaR, the repressor of the hydroxycinnamic acid catabolic genes. Chemotaxis to the three hydroxycinnamic acids was dependent on catabolism, as a mutant lacking the gene encoding feruloyl-CoA synthetase (Fcs), which catalyzes the first step in hydroxycinnamic acid degradation, was unable to respond chemotactically toward p-coumaric, caffeic, or ferulic acids. We tested whether an energy taxis mutant could detect hydroxycinnamic acids and determined that hydroxycinnamic acid sensing is mediated by the energy taxis receptor Aer2. PMID:28954643

  4. Cost, Energy, and Environmental Impact of Automated Electric Taxi Fleets in Manhattan.

    PubMed

    Bauer, Gordon S; Greenblatt, Jeffery B; Gerke, Brian F

    2018-04-17

    Shared automated electric vehicles (SAEVs) hold great promise for improving transportation access in urban centers while drastically reducing transportation-related energy consumption and air pollution. Using taxi-trip data from New York City, we develop an agent-based model to predict the battery range and charging infrastructure requirements of a fleet of SAEVs operating on Manhattan Island. We also develop a model to estimate the cost and environmental impact of providing service and perform extensive sensitivity analysis to test the robustness of our predictions. We estimate that costs will be lowest with a battery range of 50-90 mi, with either 66 chargers per square mile, rated at 11 kW or 44 chargers per square mile, rated at 22 kW. We estimate that the cost of service provided by such an SAEV fleet will be $0.29-$0.61 per revenue mile, an order of magnitude lower than the cost of service of present-day Manhattan taxis and $0.05-$0.08/mi lower than that of an automated fleet composed of any currently available hybrid or internal combustion engine vehicle (ICEV). We estimate that such an SAEV fleet drawing power from the current NYC power grid would reduce GHG emissions by 73% and energy consumption by 58% compared to an automated fleet of ICEVs.

  5. Complexities’ day-to-day dynamic evolution analysis and prediction for a Didi taxi trip network based on complex network theory

    NASA Astrophysics Data System (ADS)

    Zhang, Lin; Lu, Jian; Zhou, Jialin; Zhu, Jinqing; Li, Yunxuan; Wan, Qian

    2018-03-01

    Didi Dache is the most popular taxi order mobile app in China, which provides online taxi-hailing service. The obtained big database from this app could be used to analyze the complexities’ day-to-day dynamic evolution of Didi taxi trip network (DTTN) from the level of complex network dynamics. First, this paper proposes the data cleaning and modeling methods for expressing Nanjing’s DTTN as a complex network. Second, the three consecutive weeks’ data are cleaned to establish 21 DTTNs based on the proposed big data processing technology. Then, multiple topology measures that characterize the complexities’ day-to-day dynamic evolution of these networks are provided. Third, these measures of 21 DTTNs are calculated and subsequently explained with actual implications. They are used as a training set for modeling the BP neural network which is designed for predicting DTTN complexities evolution. Finally, the reliability of the designed BP neural network is verified by comparing with the actual data and the results obtained from ARIMA method simultaneously. Because network complexities are the basis for modeling cascading failures and conducting link prediction in complex system, this proposed research framework not only provides a novel perspective for analyzing DTTN from the level of system aggregated behavior, but can also be used to improve the DTTN management level.

  6. Pili-taxis: Clustering of Neisseria gonorrhoeae bacteria

    NASA Astrophysics Data System (ADS)

    Taktikos, Johannes; Zaburdaev, Vasily; Biais, Nicolas; Stark, Holger; Weitz, David A.

    2012-02-01

    The first step of colonization of Neisseria gonorrhoeae bacteria, the etiological agent of gonorrhea, is the attachment to human epithelial cells. The attachment of N. gonorrhoeae bacteria to surfaces or other cells is primarily mediated by filamentous appendages, called type IV pili (Tfp). Cycles of elongation and retraction of Tfp are responsible for a common bacterial motility called twitching motility which allows the bacteria to crawl over surfaces. Experimentally, N. gonorrhoeae cells initially dispersed over a surface agglomerate into round microcolonies within hours. It is so far not known whether this clustering is driven entirely by the Tfp dynamics or if chemotactic interactions are needed. Thus, we investigate whether the agglomeration may stem solely from the pili-mediated attraction between cells. By developing a statistical model for pili-taxis, we try to explain the experimental measurements of the time evolution of the mean cluster size, number of clusters, and area fraction covered by the cells.

  7. Human Mars Mission Performance Crew Taxi Profile. Part 1

    NASA Technical Reports Server (NTRS)

    Duaro, Vince A.

    1999-01-01

    This timeline was generated on the Integrated Mission Program (IMP). All burn events over 2 seconds are finite with IMP solving a two point boundary value setup for begin burn time, burn time and control angles. Perigee and apogee shown above are mean orbital values. Significant events are listed. Each finite thrust event has two lines. The first is the beginning time showing the initial conditions, thrust and ISP used. The second has the end burn conditions and the delta v and time of burn. This case is an abort from the 750 x 750 phasing abort, using the taxi's main engines. An abort using the Reaction Control System (RCS) was also investigated but required a large increase in RCS propellant and was abandoned.

  8. German taxi drivers' experiences and expressions of driving anger: Are the driving anger scale and the driving anger expression inventory valid measures?

    PubMed

    Brandenburg, Stefan; Oehl, Michael; Seigies, Kristin

    2017-11-17

    The objective of this article was 2-fold: firstly, we wanted to examine whether the original Driving Anger Scale (DAS) and the original Driving Anger Expression Inventory (DAX) apply to German professional taxi drivers because these scales have previously been given to professional and particularly to nonprofessional drivers in different countries. Secondly, we wanted to examine possible differences in driving anger experience and expression between professional German taxi drivers and nonprofessional German drivers. We applied German versions of the DAS, the DAX, and the State-Trait Anger Expression Inventory (STAXI) to a sample of 138 professional German taxi drivers. We then compared their ratings to the ratings of a sample of 1,136 nonprofessional German drivers (Oehl and Brandenburg n.d. ). Regarding our first objective, confirmatory factor analysis shows that the model fit of the DAS is better for nonprofessional drivers than for professional drivers. The DAX applies neither to professional nor to nonprofessional German drivers properly. Consequently, we suggest modified shorter versions of both scales for professional drivers. The STAXI applies to both professional and nonprofessional drivers. With respect to our second objective, we show that professional drivers experience significantly less driving anger than nonprofessional drivers, but they express more driving anger. We conclude that the STAXI can be applied to professional German taxi drivers. In contrast, for the DAS and the DAX we found particular shorter versions for professional taxi drivers. Especially for the DAX, most statements were too strong for German drivers to agree to. They do not show behaviors related to driving anger expression as they are described in the DAX. These problems with the original American DAX items are in line with several other studies in different countries. Future investigations should examine whether (professional) drivers from further countries express their anger

  9. View of the Soyuz carrying the Taxi crew during undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7129 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  10. View of the Soyuz carrying the Taxi crew during undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7130 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  11. A safety monitoring system for taxi based on CMOS imager

    NASA Astrophysics Data System (ADS)

    Liu, Zhi

    2005-01-01

    CMOS image sensors now become increasingly competitive with respect to their CCD counterparts, while adding advantages such as no blooming, simpler driving requirements and the potential of on-chip integration of sensor, analogue circuitry, and digital processing functions. A safety monitoring system for taxi based on cmos imager that can record field situation when unusual circumstance happened is described in this paper. The monitoring system is based on a CMOS imager (OV7120), which can output digital image data through parallel pixel data port. The system consists of a CMOS image sensor, a large capacity NAND FLASH ROM, a USB interface chip and a micro controller (AT90S8515). The structure of whole system and the test data is discussed and analyzed in detail.

  12. 77 FR 12103 - Notice of Request for Approval of a New Information Collection: Exemptions for Air Taxi Operations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... (DOT), OST, to request that the Office of Management and Budget (OMB) approve the following collection... Administration (FAA) to OST. The collection involves a classification of air carriers known as air taxi operators.... DOT-OST- 2004-16951] through one of the following methods: Federal eRulemaking Portal: http://www...

  13. pH-Taxis of Biohybrid Microsystems

    NASA Astrophysics Data System (ADS)

    Zhuang, Jiang; Wright Carlsen, Rika; Sitti, Metin

    2015-06-01

    The last decade has seen an increasing number of studies developing bacteria and other cell-integrated biohybrid microsystems. However, the highly stochastic motion of these microsystems severely limits their potential use. Here, we present a method that exploits the pH sensing of flagellated bacteria to realize robust drift control of multi-bacteria propelled microrobots. Under three specifically configured pH gradients, we demonstrate that the microrobots exhibit both unidirectional and bidirectional pH-tactic behaviors, which are also observed in free-swimming bacteria. From trajectory analysis, we find that the swimming direction and speed biases are two major factors that contribute to their tactic drift motion. The motion analysis of microrobots also sheds light on the propulsion dynamics of the flagellated bacteria as bioactuators. It is expected that similar driving mechanisms are shared among pH-taxis, chemotaxis, and thermotaxis. By identifying the mechanism that drives the tactic behavior of bacteria-propelled microsystems, this study opens up an avenue towards improving the control of biohybrid microsystems. Furthermore, assuming that it is possible to tune the preferred pH of bioactuators by genetic engineering, these biohybrid microsystems could potentially be applied to sense the pH gradient induced by cancerous cells in stagnant fluids inside human body and realize targeted drug delivery.

  14. Injuries and absenteeism among motorcycle taxi drivers who are victims of traffic accidents.

    PubMed

    Barbosa, Kevan G N; Lucas-Neto, Alfredo; Gama, Bruno D; Lima-Neto, Jose C; Lucas, Rilva Suely C C; d'Ávila, Sérgio

    2014-08-01

    Facial injuries frequently occur in traffic accidents involving motorcycles. The purpose of this study was to determine the prevalence of facial injuries among motorcycle drivers who perform motorcycle taxi service. The study design was cross-sectional. A total of 210 participants who served as motorcycle taxi drivers in a city in northeastern Brazil completed a survey concerning their experience of accidents involving facial injuries and consequent hospitalization and absenteeism from work. The motorcycle drivers included in the study were randomly selected from a list provided by the city. Out of the respondents, 165 (78.6%) who were involved in traffic accidents in the last 12 months, 15 (9.1%) reported facial injuries. The types of facial injury most frequently reported involved soft tissues (n = 8; 53.3%), followed by simple fracture (n = 4; 26.7%) and dentoalveolar fracture (n = 3; 20%). We found an association between facial injuries and absenteeism, as well as an association between the presence of facial injury and the need for hospitalization for a period of 2 days or more. Respondents reported that they had accidents, but due to the use of full face motorcycle helmet the number of facial injuries was low. For most of them, absenteeism was observed for a period of one month or more. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  15. An empirical investigation of taxi driver response behavior to ride-hailing requests: A spatio-temporal perspective

    PubMed Central

    Xu, Ke; Sun, Luping; Wang, Hansheng

    2018-01-01

    Using data provided by a ride-hailing platform, this paper examines the factors that affect taxi driver response behavior to ride-hailing requests. The empirical investigation from a driver’s perspective is of great importance for ride-hailing service providers, given that approximately 40% of the hailing requests receive no response from any driver. To comprehensively understand taxi driver response behavior, we use a rich dataset to generate variables related to the spatio-temporal supply-demand intensities, the economic incentives, the requests’ and the drivers’ characteristics. The results show that drivers are more likely to respond to requests with economic incentives (especially a firm subsidy), and those with a lower spatio-temporal demand intensity or a higher spatio-temporal supply intensity. In addition, drivers are more likely to respond to requests involving rides covering a greater geographical distance and to those with a smaller number of repeated submissions. The drivers’ characteristics, namely, the number of requests received and the number of requests responded, however, have relatively little impacts on their response probability to the current request. Our findings contribute to the related literature and provide managerial implications for ride-hailing service providers. PMID:29883478

  16. NASA's space shuttle Atlantis and its 747 carrier taxied on the Edwards Air Force Base flightline as

    NASA Technical Reports Server (NTRS)

    2001-01-01

    NASA's space shuttle Atlantis and its 747 carrier taxied on the Edwards Air Force Base flightline as the unusual combination left for Kennedy Space Center, Florida, on March 1, 2001. Atlantis and the shuttle Columbia were both airborne on the same day as they migrated from California to Florida. Columbia underwent refurbishing at nearby Palmdale, California.

  17. View of the Soyuz carrying the Taxi crew during undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7121 (31 October 2001) --- Backdropped by Earth’s horizon and the blackness of space, a Soyuz spacecraft undocks from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  18. View of the Soyuz carrying the Taxi crew during undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7127 (31 October 2001) --- Backdropped by the blackness of space, a Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  19. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7096 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  20. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7101 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  1. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7094 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  2. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7100 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  3. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7097 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  4. View of the Soyuz carrying the Taxi crew after undocking taken during Expedition Three

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7107 (31 October 2001) --- A Soyuz spacecraft departs from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  5. Personal exposures to airborne metals in London taxi drivers and office workers in 1995 and 1996.

    PubMed

    Pfeifer, G D; Harrison, R M; Lynam, D R

    1999-09-01

    In 1995, a petroleum marketer introduced a diesel fuel additive in the UK containing Mn as MMT (methylcyclopentadienyl manganese tricarbonyl). A small study of personal exposures to airborne Mn in London was conducted before and after introduction of the additive to identify any major impact of the additive on exposures. In 1995, personal exposures to Mn were measured in two groups, taxi drivers and office workers (10 subjects per group) for two consecutive 7-day periods. A similar study was carried out in 1996 to determine if exposures had changed. Samples were also analyzed for Ca, Al, Mg and Pb. In 1996, exposures to aerosol mass as total suspended particulates (TSP) and PM2.5 were measured in addition to the metals. Manganese exposures in this cohort did not increase as a result of introduction of the additive. However, a significant source of Mn exposure was discovered during the conduct of these tests. The mean exposure to Mn was higher among the office workers in both years than that of the taxi drivers. This was due to the fact that approximately half of the office workers commuted via the underground railway system where airborne dust and metal concentrations are significantly elevated over those in the general environment. Similar results have been noted in other cities having underground rail systems. Exposure to Mn, Pb, Ca, and Mg were not significantly different between the 2 years. Taxi drivers had higher exposures than office workers to Mg and Pb in both years. Commuting via the underground also had a significant impact on exposures to TSP, PM2.5, Al, and Ca, but had little effect on exposures to Mg. The aerosol in the underground was particularly enriched in Mn, approximately 10-fold, when compared to the aerosol in the general environment. There are several possible sources for this Mn, including mechanical wear of the steel wheels on the steel rais, vaporization of metal from sparking of the third rail, or brake wear.

  6. X-Wing RSRA - 80 Knot Taxi Test

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The Rotor Systems Research Aircraft/X-Wing, a vehicle that was used to demonstrate an advanced rotor/fixed wing concept called X-Wing, is shown here during high-speed taxi tests at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, on 4 November 1987. During these tests, the vehicle made three taxi tests at speeds of up to 138 knots. On the third run, the RSRA/X-Wing lifted off the runway to a 25-foot height for about 16 seconds. This liftoff maneuver was pre-planned as an aid to evaluations for first flight. At the controls were NASA pilot G. Warren Hall and Sikorsky pilot W. Faull. The unusual aircraft that resulted from the Ames Research Center/Army X-Wing Project was flown at the Ames-Dryden Flight Research Facility (now Dryden Flight Research Center), Edwards, California, beginning in the spring of 1984, with a follow-on program beginning in 1986. The program, was conceived to provide an efficient combination of the vertical lift characteristic of conventional helicopters and the high cruise speed of fixed-wing aircraft. It consisted of a hybrid vehicle called the NASA/Army Rotor Systems Research Aircraft (RSRA), which was equipped with advanced X-wing rotor systems. The program began in the early 1970s to investigate ways to increase the speed of rotor aircraft, as well as their performance, reliability, and safety . It also sought to reduce the noise, vibration, and maintenance costs of helicopters. Sikorsky Aircraft Division of United Technologies Laboratories built two RSRA aircraft. NASA's Langley Research Center, Hampton, Virginia, did some initial testing and transferred the program to Ames Research Center, Mountain View, California, for an extensive flight research program conducted by Ames and the Army. The purpose of the 1984 tests was to demonstrate the fixed-wing capability of the helicopter/airplane hybrid research vehicle and explore its flight envelope and flying qualities. These

  7. Changes in functional connectivity dynamics associated with vigilance network in taxi drivers.

    PubMed

    Shen, Hui; Li, Zhenfeng; Qin, Jian; Liu, Qiang; Wang, Lubin; Zeng, Ling-Li; Li, Hong; Hu, Dewen

    2016-01-01

    An increasing number of neuroimaging studies have suggested that the fluctuations of low-frequency resting-state functional connectivity (FC) are not noise but are instead linked to the shift between distinct cognitive states. However, there is very limited knowledge about whether and how the fluctuations of FC at rest are influenced by long-term training and experience. Here, we investigated how the dynamics of resting-state FC are linked to driving behavior by comparing 20 licensed taxi drivers with 20 healthy non-drivers using a sliding window approach. We found that the driving experience could be effectively decoded with 90% (p<0.001) accuracy by the amplitude of low-frequency fluctuations in some specific connections, based on a multivariate pattern analysis technique. Interestingly, the majority of these connections fell within a set of distributed regions named "the vigilance network". Moreover, the decreased amplitude of the FC fluctuations within the vigilance network in the drivers was negatively correlated with the number of years that they had driven a taxi. Furthermore, temporally quasi-stable functional connectivity segmentation revealed significant differences between the drivers and non-drivers in the dwell time of specific vigilance-related transient brain states, although the brain's repertoire of functional states was preserved. Overall, these results suggested a significant link between the changes in the time-dependent aspects of resting-state FC within the vigilance network and long-term driving experiences. The results not only improve our understanding of how the brain supports driving behavior but also shed new light on the relationship between the dynamics of functional brain networks and individual behaviors. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Association of heart rate variability in taxi drivers with marked changes in particulate air pollution in Beijing in 2008.

    PubMed

    Wu, Shaowei; Deng, Furong; Niu, Jie; Huang, Qinsheng; Liu, Youcheng; Guo, Xinbiao

    2010-01-01

    Heart rate variability (HRV), a marker of cardiac autonomic function, has been -associated with particulate matter (PM) air pollution, especially in older patients and those with cardio-vascular diseases. However, the effect of PM exposure on cardiac autonomic function in young, healthy adults has received less attention. We evaluated the relationship between exposure to traffic-related PM with an aerodynamic diameter taxi drivers. Continuous measurements of personal exposure to PM2.5 and ambulatory electrocardiogram monitoring were conducted on 11 young healthy taxi drivers for a 12-hr work shift during their work time (09002100 hr) before, during, and after the Beijing 2008 Olympic Games. Mixed-effects regression models were used to estimate associations between PM2.5 exposure and percent changes in 5-min HRV indices after combining data from the three time periods and controlling for potentially confounding variables. Personal exposures of taxi drivers to PM2.5 changed markedly across the three time -periods. The standard deviation of normal-to-normal (SDNN) intervals decreased by 2.2% [95% confidence interval (CI), 3.8% to 0.6%] with an interquartile range (IQR; 69.5 microg/m3) increase in the 30-min PM2.5 moving average, whereas the low-frequency and high-frequency powers decreased by 4.2% (95% CI, 9.0% to 0.8%) and 6.2% (95% CI, 10.7% to 1.5%), respectively, in association with an IQR increase in the 2-hr PM2.5 moving average. Marked changes in traffic-related PM2.5 exposure were associated with altered cardiac autonomic function in young healthy adults.

  9. The Soyuz Taxi crew pose for a group photo in Zvezda during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7033 (23-31 October 2001) --- The Soyuz Taxi crewmembers assemble for a group photo in the Zvezda Service Module on the International Space Station (ISS). From the left are Flight Engineer Konstantin Kozeev, Commander Victor Afanasyev, and French Flight Engineer Claudie Haignere. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  10. Availability, functionality, and use of seat belts in Beijing taxis prior to the 2008 Beijing Olympic Games.

    PubMed

    Fleiter, Judy J; Gao, Liping; Qiu, Chen; Shi, Kan

    2009-03-01

    Use of driver seat belts and availability and functionality of passenger seat belts in a convenience sample of 231 Beijing taxis were examined in the months prior to the 2008 Beijing Olympic Games. Driver and front passenger seat belt use was mandated in China from 2004 to help address the growing public health crisis of road trauma. Results from observations made by in-vehicle passengers revealed that 21.2% of drivers were correctly wearing a belt, approximately half were not, and one third were using the belt in a non-functional way. Over 3/4 of this sample of taxi drivers were unrestrained while working. The percentage of functionally available belts was higher for front than rear passengers (88.3% and 22.9%, respectively). This low rate of belt availability in rear seats calls into question the preparedness of the fleet to cater for the safety needs of foreign visitors to China, particularly those from countries with high levels of restraint use. Factors influencing the use/misuse of seat belts in China remain largely unexplored. Results of this pilot study support further investigations of barriers to using injury prevention mechanisms such as seat belts in less motorised countries.

  11. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6840 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  12. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6849 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  13. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6851 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  14. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6841 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  15. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6847 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  16. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6844 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  17. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6845 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  18. View of the approach of the Soyuz carrying the Taxi crew taken during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-6850 (23 October 2001) --- A Soyuz spacecraft approaches the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere for an eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  19. Association of Heart Rate Variability in Taxi Drivers with Marked Changes in Particulate Air Pollution in Beijing in 2008

    PubMed Central

    Wu, Shaowei; Deng, Furong; Niu, Jie; Huang, Qinsheng; Liu, Youcheng; Guo, Xinbiao

    2010-01-01

    Background Heart rate variability (HRV), a marker of cardiac autonomic function, has been associated with particulate matter (PM) air pollution, especially in older patients and those with cardiovascular diseases. However, the effect of PM exposure on cardiac autonomic function in young, healthy adults has received less attention. Objectives We evaluated the relationship between exposure to traffic-related PM with an aerodynamic diameter ≤ 2.5 μm (PM2.5) and HRV in a highly exposed panel of taxi drivers. Methods Continuous measurements of personal exposure to PM2.5 and ambulatory electrocardiogram monitoring were conducted on 11 young healthy taxi drivers for a 12-hr work shift during their work time (0900–2100 hr) before, during, and after the Beijing 2008 Olympic Games. Mixed-effects regression models were used to estimate associations between PM2.5 exposure and percent changes in 5-min HRV indices after combining data from the three time periods and controlling for potentially confounding variables. Results Personal exposures of taxi drivers to PM2.5 changed markedly across the three time periods. The standard deviation of normal-to-normal (SDNN) intervals decreased by 2.2% [95% confidence interval (CI), −3.8% to −0.6%] with an interquartile range (IQR; 69.5 μg/m3) increase in the 30-min PM2.5 moving average, whereas the low-frequency and high-frequency powers decreased by 4.2% (95% CI, −9.0% to 0.8%) and 6.2% (95% CI, −10.7% to −1.5%), respectively, in association with an IQR increase in the 2-hr PM2.5 moving average. Conclusions Marked changes in traffic-related PM2.5 exposure were associated with altered cardiac autonomic function in young healthy adults. PMID:20056565

  20. Effect of free distribution of safety equipment on usage among motorcycle-taxi drivers in Tanzania--A cluster randomised controlled trial.

    PubMed

    Sumner, Steven A; Pallangyo, Anthony J; Reddy, Elizabeth A; Maro, Venance; Pence, Brian W; Lynch, Catherine; Turner, Elizabeth L; Egger, Joseph R; Thielman, Nathan M

    2014-11-01

    Deaths due to road traffic injuries, particularly motorcycle crashes, have increased rapidly in many African nations and context-specific strategies to improve preventative behaviours are needed. Although adhering to conspicuity measures by wearing reflective safety vests is a highly effective crash prevention strategy and mandated by law among motorcycle-taxi drivers in some African countries, actual use is currently low. We aimed to test whether eliminating cost-barriers through the provision of free reflective, fluorescent motorcycle safety vests would lead to increased utilisation among a high-risk population of motorcycle-taxi drivers in Tanzania. A cluster randomised controlled trial was conducted among 180 motorcycle-taxi drivers. Participants randomised to the intervention arm (90) received free, reflective, fluorescent vests; participants randomised to the control arm (90) did not receive free vests. Participants' use of reflective vests was then observed on city streets over a three month period and differential uptake was estimated using mixed-effects logistic regression. Baseline use of reflective vests was 3.3% in both arms. Seventy-nine drivers in the intervention arm and 82 drivers in the control arm were observed during follow-up. The average proportion of observations during which motorcycle drivers were using a reflective vest was 9.5% in the intervention arm, compared to 2.0% in the control arm (odds ratio: 5.5, 95% confidence interval: 1.1-26.9, p-value: 0.04). Although distribution of free reflective vests led to a statistically significant increase in vest usage, the absolute increase was modest. Additional strategies beyond removing economic barriers are important to augment adherence to road safety behaviours for injury prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Boundedness and global stability of the two-predator and one-prey models with nonlinear prey-taxis

    NASA Astrophysics Data System (ADS)

    Wang, Jianping; Wang, Mingxin

    2018-06-01

    This paper concerns the reaction-diffusion systems modeling the population dynamics of two predators and one prey with nonlinear prey-taxis. We first investigate the global existence and boundedness of the unique classical solution for the general model. Then, we study the global stabilities of nonnegative spatially homogeneous equilibria for an explicit system with type I functional responses and density-dependent death rates for the predators and logistic growth for the prey. Moreover, the convergence rates are also established.

  2. Factors associated with drug use among male motorbike taxi drivers in urban Vietnam.

    PubMed

    Nguyen, Huy Van; Vu, Thinh Toan; Pham, Ha Nguyen

    2014-08-01

    A cross-sectional study was conducted on a sample of 291 male motorbike taxi drivers (MMTDs) recruited through social mapping technique in Hanoi, Vietnam, for face-to-face interviews to examine factors associated with drug use among MMTDs using Information-Motivation-Behavioral skills (IMB) model. Among 291 MMTDs, 17.18% reported drug use sometime in their lives, 96% of whom were drug injectors. Being depressed, being originally borne in urban cities, currently residing in rural areas, having a longer time living apart from their wives/lovers, using alcohol, following Buddhism, and reporting lower motivation of HIV prevention predict significantly higher odds of uptaking drugs.

  3. View of the Soyuz carrying the Taxi crew during undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7118 (31 October 2001) --- A Soyuz spacecraft, backdropped by Earth’s horizon and the blackness of space, is photographed prior to departure from the International Space Station (ISS), carrying the Soyuz taxi crew back to Earth, ending their eight-day stay on the station. The crewmembers are Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  4. Determining of the Parking Manoeuvre and the Taxi Blockage Adjustment Factor for the Saturation Flow Rate at the Outlet Legs of Signalized Intersections: Case Study from Rasht City (Iran)

    NASA Astrophysics Data System (ADS)

    Behbahani, Hamid; Jahangir Samet, Mehdi; Najafi Moghaddam Gilani, Vahid; Amini, Amir

    2017-10-01

    The presence of taxi stops within the area of signalized intersections at the outlet legs due to unnatural behaviour of the taxis, sudden change of lanes, parking manoeuvres activities and stopping the vehicle to discharge or pick up the passengers have led to reduction of saturation flow rate at the outlet leg of signalized intersections and increased delay as well as affecting the performance of a crossing lane. So far, in term of evaluating effective adjustment factors on saturation flow rate at the inlet legs of the signalized intersections, various studies have been carried out, however; there has not been any studies on effective adjustment factors on saturation flow rate at the inlet legs. Hence, the evaluating of the traffic effects of unique behaviours on the saturation flow rate of the outlet leg is very important. In this research the parking manoeuvre time and taxi blockage time were evaluated and analyzed based on the available lane width as well as determining the effective adjustment factors on the saturation flow rate using recording related data at four signalized intersections in Rasht city. The results show that the average parking manoeuvre time is a function of the lane width and is increased as the lane width is reduced. Also, it is suggested to use the values of 7.37 and 11.31 seconds, respectively for the average parking manoeuvre time and the average blockage time of taxies at the outlet legs of signalized intersections for the traffic designing in Rasht city.

  5. Exposures to PM₂.₅ components and heart rate variability in taxi drivers around the Beijing 2008 Olympic Games.

    PubMed

    Wu, Shaowei; Deng, Furong; Niu, Jie; Huang, Qinsheng; Liu, Youcheng; Guo, Xinbiao

    2011-06-01

    Carbonaceous and metallic components of particles have been shown to play a role in particles' effects on cardiac autonomic function as measured by heart rate variability (HRV). Previously we reported the association of HRV with marked changes in traffic-related particulate air pollution around the Beijing 2008 Olympic Games in a panel of taxi drivers. We further investigated the relationship between exposures to the carbonaceous and metallic components of traffic-related particles and HRV in the same population. Repeated measurements of in-car exposures to particulate matter ≤ 2.5 μm in aerodynamic diameter (PM₂.₅), carbon monoxide and nitrogen oxides were conducted in a group of 14 taxi drivers for one work shift in four study periods around the Beijing 2008 Olympics. The quantities of organic/elemental carbons and 27 elements of the in-car PM₂.₅ mass were determined laboratorially. Linear mixed-effects models were used to evaluate the impact of exposures to different PM₂.₅ components on HRV while controlling for potential confounders. Taxi drivers' exposures to in-car PM₂.₅ and its components showed dramatic changes across the four study periods around the Beijing 2008 Olympics. Differences in associations of in-car PM₂.₅ components with HRV were found. An interquartile range (IQR: 917.9 ng/m³) increase in calcium was associated with a 5.48 millisecond [ms, 95% confidence interval (CI): 0.71, 10.24] increase in standard deviations of normal-to-normal (SDNN) intervals, while an IQR (4.1 ng/m³) increase in nickel was associated with a 1.53 ms (95% CI: 0.14, 2.92) increase in SDNN index. Additionally, a decline of 8.11 ms (95% CI: -15.26, -0.97) in SDNN per IQR (481.4 ng/m³) increase in iron was also found. The results support associations of PM₂.₅ metallic components with HRV in younger healthy individuals. Future studies are needed to clarify the interaction among different PM₂.₅ components or the role of PM₂.₅ mixtures

  6. Distant view of the Soyuz carrying the Taxi crew after undocking from the ISS

    NASA Image and Video Library

    2001-10-31

    ISS003-E-7131 (31 October 2001) --- Backdropped by Earth’s horizon and the blackness of space, this distant view shows a Soyuz spacecraft after undocking from the International Space Station (ISS) carrying the Soyuz taxi crew, Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere, ending their eight-day stay on the station. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  7. Occupational and personal factors associated with acquired lumbar spondylolisthesis of urban taxi drivers

    PubMed Central

    Chen, J; Chan, W; Katz, J; Chang, W; Christiani, D

    2004-01-01

    Aims: To investigate the occupational and personal factors associated with lumbar spondylolisthesis in taxi drivers. Methods: Cross-sectional analysis of the baseline data from the Taxi Drivers' Health Study cohort. Information was retrieved from the medical records of standardised lumbosacral spine plain films, age, and anthropometric measures of 1242 subjects. Acquired spondylolisthesis (ASL) was defined as non-lytic spondylolisthesis involving lumbar spines above L5. Questionnaires were used to gather information on demographic features, health behaviours, exercise, work related physical and psychosocial factors, and driving time profiles. Multiple logistic regression was used to model the odds ratio (OR) for prevalent ASL cases associated with personal and occupational factors. Results: A total of 40 cases (3.2%) of ASL were diagnosed. Among those driving ⩽5 years, 6–15 years, and >15 years, the estimated prevalence of lumbar spondylolisthesis was 1.1%, 2.4%, and 7.1% respectively. Results of multiple logistic regression suggested that taxicab driving >15 years (OR = 3.4, 95% CI 1.1 to 10.7, compared to driving ⩽5 years), age (OR = 2.6, 95% CI 1.1 to 6.6 for age 46–55; and OR = 4.8, 95% CI 1.8 to 12.9 for age >55), body mass index ⩾25 kg/m2 (OR = 2.2, 95% CI 1.1 to 4.6), and frequent strenuous exercise (OR = 2.2, 95% CI 1.1 to 4.5) were significantly associated with higher prevalence of spondylolisthesis. There was a consistent likely exposure-response relation between professional seniority and ASL prevalence. Conclusions: Longitudinal studies are needed to confirm the observed association between professional driving and spondylolisthesis, and to examine further the specific occupational exposures accountable for this association. PMID:15550605

  8. "Dammed Taxi Cab"--How Silent Communication in Questionnaires Can Be Understood and Used to Give Voice to Children's Experiences

    ERIC Educational Resources Information Center

    Alerby, E.; Kostenius, C.

    2011-01-01

    "Dammed taxi cab"--a 12-year-old boy wrote these words in the margins of a questionnaire, and within this paper they will serve as a point of departure for the discussion of the use of questionnaires as a way to voice children's experiences. The overall aim of this paper is to enable understanding of and discuss the use of questionnaires as a way…

  9. Large-scale functional brain network changes in taxi drivers: evidence from resting-state fMRI.

    PubMed

    Wang, Lubin; Liu, Qiang; Shen, Hui; Li, Hong; Hu, Dewen

    2015-03-01

    Driving a car in the environment is a complex behavior that involves cognitive processing of visual information to generate the proper motor outputs and action controls. Previous neuroimaging studies have used virtual simulation to identify the brain areas that are associated with various driving-related tasks. Few studies, however, have focused on the specific patterns of functional organization in the driver's brain. The aim of this study was to assess differences in the resting-state networks (RSNs) of the brains of drivers and nondrivers. Forty healthy subjects (20 licensed taxi drivers, 20 nondrivers) underwent an 8-min resting-state functional MRI acquisition. Using independent component analysis, three sensory (primary and extrastriate visual, sensorimotor) RSNs and four cognitive (anterior and posterior default mode, left and right frontoparietal) RSNs were retrieved from the data. We then examined the group differences in the intrinsic brain activity of each RSN and in the functional network connectivity (FNC) between the RSNs. We found that the drivers had reduced intrinsic brain activity in the visual RSNs and reduced FNC between the sensory RSNs compared with the nondrivers. The major finding of this study, however, was that the FNC between the cognitive and sensory RSNs became more positively or less negatively correlated in the drivers relative to that in the nondrivers. Notably, the strength of the FNC between the left frontoparietal and primary visual RSNs was positively correlated with the number of taxi-driving years. Our findings may provide new insight into how the brain supports driving behavior. © 2014 Wiley Periodicals, Inc.

  10. Sociodemographic factors associated with aggressive driving behaviors of 3-wheeler taxi drivers in Sri Lanka.

    PubMed

    Akalanka, Ediriweera Chintana; Fujiwara, Takeo; Desapriya, Ediriweera; Peiris, Dinithi C; Scime, Giulia

    2012-01-01

    Little is known about the nature and scope of aggressive driving in developing countries. The objective of this study is to specifically examine the sociodemographic factors associated with aggressive driving behavior among 3-wheeler taxi drivers in Sri Lanka. Convenience samples of 3-wheeler taxi drivers from Rathnapura, Ahaliyagoda, Sri Lanka were surveyed from June to August 2006. Analyses included bivariate and multivariate logistic regression. Drivers with less than high school education were 3.5 times more likely to drive aggressively (odds ratio [OR] = 3.46; 95% confidence interval [CI] = 1.08, 11.1). Single drivers were 9 times more likely to run red lights (OR = 8.74; 95% CI = 2.18, 35.0), and being single was a major risk factor for drunk driving (OR = 4.80; 95% CI = 1.23, 18.7). Furthermore, high school completers were 4 times more likely to bribe a policeman (OR = 4.27; 95% CI = 1.23, 14.9) when caught violating the road rules. Aggressive driving and risk-taking behavior are amenable to policy initiatives, and preventive programs targeted at key groups could be used to improve road safety in Sri Lanka. This study demonstrates that aggressive driving behavior is associated with sociodemographic factors, including the level of education, marital status, and other socioeconomic factors. Hence, economic factors should be addressed to find solutions to traffic-related issues. It will be the government's and policy makers' responsibility to try and understand the economic factors behind risky road behavior and bribe-taking behavior prior to legislating or enforcing new laws.

  11. Taxi and Expedition Three crews pose for a group photo in Zvezda during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7036 (23-31 October 2001) --- Astronaut Frank L. Culbertson, Jr. (foreground), Expedition Three mission commander, and the Soyuz Taxi crewmembers assemble for a group photo in the Zvezda Service Module on the International Space Station (ISS). From the left are Flight Engineer Konstantin Kozeev, Commander Victor Afanasyev, and French Flight Engineer Claudie Haignere. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  12. The Soyuz Taxi crew wave through a Soyuz hatch during their visit to the ISS

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7251 (23-31 October 2001) --- The Soyuz Taxi crewmembers wave from a Soyuz spacecraft docked to the International Space Station (ISS). Clockwise from the top are Commander Victor Afanasyev, Flight Engineer Konstantin Kozeev and French Flight Engineer Claudie Haignere. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera by one of the Expedition Three crew from the nadir docking port on the station.

  13. Taxi and Expedition Three crews pose for a group photo in Zvezda during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7037 (23-31 October 2001) --- Astronaut Frank L. Culbertson, Jr. (foreground), Expedition Three mission commander, and the Soyuz Taxi crewmembers assemble for a group photo in the Zvezda Service Module on the International Space Station (ISS). From the left are Flight Engineer Konstantin Kozeev, Commander Victor Afanasyev, and French Flight Engineer Claudie Haignere. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  14. The Soyuz Taxi crew adhere their logo to a wall in Node 1 during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7056 (23-31 October 2001) --- The Soyuz Taxi crewmembers, Commander Victor Afanasyev (left), French Flight Engineer Claudie Haignere and Flight Engineer Konstantin Kozeev, add their crew patch to the growing collection, in the Unity node, of insignias representing crews who have worked on the International Space Station (ISS). Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  15. The Soyuz Taxi crew pose with the ISS ship log in Node 1 during Expedition Three

    NASA Image and Video Library

    2001-10-23

    ISS003-E-7084 (23-31 October 2001) --- The Soyuz Taxi crewmembers, Flight Engineer Konstantin Kozeev (left), Commander Victor Afanasyev and French Flight Engineer Claudie Haignere add their names to the list of the International Space Station (ISS) visitors in the ship’s log in the Unity node. Afanasyev and Kozeev represent Rosaviakosmos, and Haignere represents ESA, carrying out a flight program for CNES, the French Space Agency, under a commercial contract with the Russian Aviation and Space Agency. This image was taken with a digital still camera.

  16. PERFORMANCE AND DURABILITY OF THE PSA PEUGEOT CITROEN'S DPF SYSTEM ON A TAXI FLEET IN THE PARIS AREA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    COROLLER, P; PLASSAT, G

    The use of Diesel engines has strongly increased during the last years and now represents 40% of the sales in Europe and up to 50% of the number of cars in circulation for some countries. This success is linked not only to the economical aspect of the use of such vehicles, but also to the recent technological improvements of these engines. The new technical solutions (high pressure direct injection, turbocharger) have indeed allowed the increase of these engine performances while decreasing their fuel consumption, pollutant emissions and noise level. From an environment point of view, Diesel engines are nevertheless penalizedmore » by their particulates and NOx emissions. The study and the treatment of the particulate, highly criticized for their potential impact on health, are the subject of numerous works of characterizations and developments. PSA Peugeot Citroen has recently (2000) launched its particulate filter technology on several types of vehicles (500,000 vehicles with DPF have been sold today). In order to evaluate the durability of this technology over a long period of time, a study program has been set-up by ADEME (French Environmental Agency), IFP Powertrain, PSA Peugeot Citroen and Taxis G7 (a Parisian taxis Company). The objective is to study the evolution of five taxis and their after-treatment system performances over 80,000km mileage--which corresponds to the recommended mileage before the first DPF maintenance--in hard urban driving conditions, as well over 120,000km, after the DPF maintenance and remanufacturing. More specifically, the following evaluations are being performed at regular intervals (around 20,000km): regulated gaseous pollutant emissions on NEDC cycle, particulate emissions and unregulated pollutant emissions. The results obtained until now have not shown any degradation of the particulate filter efficiency (more than 90%). This paper presents the methodology set-up, and the explanation of the first results obtained. Indeed, a

  17. HIV related risk behaviours among taxi drivers and their assistants in Addis Ababa, Ethiopia: descriptive cross-sectional survey.

    PubMed

    Lakew, Yihunie; Tamene, Habtamu

    2014-04-08

    Risk taking behaviours in relation to HIV among the mobile population is a growing public health concern in many developing countries, including Ethiopia. The aim of this study was to describe risky sexual behaviours and associated factors among male taxi drivers and assistants in Addis Ababa. A descriptive cross-sectional survey design with multistage cluster sampling procedure was employed to select 615 individuals for interview. Seventy six percent of the respondents were sexually active. Nearly 31% of the respondents reported casual sex and 7% of them did not use a condom with their most recent casual sex partner. More than half (58.5%) of the respondents had no condom use efficacy. Condom breakage and/or slippage during sex had been encountered by 44% of respondents with casual partners and sex during menstruation had ever occurred among 17% of respondents. Eleven percent had experienced sex with female sex workers. Thirty-three percent of the respondents were unfaithful to their spouse/steady partners. Multivariate analysis revealed that living with parents [AOR 95% CI; 2(1.14-3.60)], non-khat chewers [AOR 95% CI; 3.7(2.13-6.31)], never taken VCT [AOR 95% CI; 3.5(1.84-6.72)], middle-class monthly cash gain [AOR 95% CI; 0.5(0.25-0.98)] and more years of experience working on a taxi [AOR 95% CI; 0.17(0.60-0.47)] were statistically significant to influence lifetime abstinence. Non-khat chewers [AOR 95% CI; 0.53(0.37-0.78)], never taken VCT [AOR 95% CI; 0.54(0.36-0.88)] and higher monthly cash gain [AOR 95% CI; 2.9(1.14-7.19)] had a statistically significant association with condom use efficacy. Living with parents [AOR 95% CI; 2(1.31-3.72)], living with friends [AOR 95% CI; 6.4(3.13-12.89)] and non-khat chewers [AOR 95% CI; 2(1.34-3.53)] were risk factors found to be associated with faithfulness. Risky sexual behaviours in this sub-population were considerable and associated factors were found to be multidimensional. Therefore, there is a need for robust

  18. A coordinated sequence of distinct flagellar waveforms enables a sharp flagellar turn mediated by squid sperm pH-taxis.

    PubMed

    Iida, Tomohiro; Iwata, Yoko; Mohri, Tatsuma; Baba, Shoji A; Hirohashi, Noritaka

    2017-10-11

    Animal spermatozoa navigate by sensing ambient chemicals to reach the site of fertilization. Generally, such chemicals derive from the female reproductive organs or cells. Exceptionally, squid spermatozoa mutually release and perceive carbon dioxide to form clusters after ejaculation. We previously identified the pH-taxis by which each spermatozoon can execute a sharp turn, but how flagellar dynamics enable this movement remains unknown. Here, we show that initiation of the turn motion requires a swim down a steep proton gradient (a theoretical estimation of ≥0.025 pH/s), crossing a threshold pH value of ~5.5. Time-resolved kinematic analysis revealed that the turn sequence results from the rhythmic exercise of two flagellar motions: a stereotypical flagellar 'bent-cane' shape followed by asymmetric wave propagation, which enables a sharp turn in the realm of low Reynolds numbers. This turning episode is terminated by an 'overshoot' trajectory that differs from either straight-line motility or turning. As with bidirectional pH-taxes in some bacteria, squid spermatozoa also showed repulsion from strong acid conditions with similar flagellar kinematics as in positive pH-taxis. These findings indicate that squid spermatozoa might have a unique reorientation mechanism, which could be dissimilar to that of classical egg-guided sperm chemotaxis in other marine invertebrates.

  19. Learning and evolution in bacterial taxis: an operational amplifier circuit modeling the computational dynamics of the prokaryotic 'two component system' protein network.

    PubMed

    Di Paola, Vieri; Marijuán, Pedro C; Lahoz-Beltra, Rafael

    2004-01-01

    Adaptive behavior in unicellular organisms (i.e., bacteria) depends on highly organized networks of proteins governing purposefully the myriad of molecular processes occurring within the cellular system. For instance, bacteria are able to explore the environment within which they develop by utilizing the motility of their flagellar system as well as a sophisticated biochemical navigation system that samples the environmental conditions surrounding the cell, searching for nutrients or moving away from toxic substances or dangerous physical conditions. In this paper we discuss how proteins of the intervening signal transduction network could be modeled as artificial neurons, simulating the dynamical aspects of the bacterial taxis. The model is based on the assumption that, in some important aspects, proteins can be considered as processing elements or McCulloch-Pitts artificial neurons that transfer and process information from the bacterium's membrane surface to the flagellar motor. This simulation of bacterial taxis has been carried out on a hardware realization of a McCulloch-Pitts artificial neuron using an operational amplifier. Based on the behavior of the operational amplifier we produce a model of the interaction between CheY and FliM, elements of the prokaryotic two component system controlling chemotaxis, as well as a simulation of learning and evolution processes in bacterial taxis. On the one side, our simulation results indicate that, computationally, these protein 'switches' are similar to McCulloch-Pitts artificial neurons, suggesting a bridge between evolution and learning in dynamical systems at cellular and molecular levels and the evolutive hardware approach. On the other side, important protein 'tactilizing' properties are not tapped by the model, and this suggests further complexity steps to explore in the approach to biological molecular computing.

  20. Injury severity analysis in taxi-pedestrian crashes: An application of reconstructed crash data using a vehicle black box.

    PubMed

    Chung, Younshik

    2018-02-01

    In-vehicle recording devices have enabled recent changes in methodological paradigms for traffic safety research. Such devices include event data recorders (EDRs), vehicle black boxes (VBBs), and various sensors used in naturalistic driving studies (NDSs). These technologies may help improve the validity of models used to assess impacts on traffic safety. The objective of this study is to analyze the injury severity in taxi-pedestrian crashes using the accurate crash data from VBBs, such as the time-to-collision (TTC), speed, angle, and region of the crash. VBB data from a two-year period (2010-2011) were collected from taxis operating in Incheon, South Korea. An ordered probit model was then applied to analyze the injury severity in crashes. Five variables were found to have a greater effect on injury severity: crash speed, crashes in no-median sections, crashes where the secondary impact object of pedestrians was the crash vehicle, crashes where the third impact object of pedestrians was another moving vehicle, and crashes where the third impact region of pedestrians was their head. However, injuries were less severe in crashes where the first impact region on the pedestrian was their leg, crashes with the car moving in a straight line, and crashes involving junior high school students. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. The Effects of Projected Future Demand Including Very Light Jet Air-Taxi Operations on U.S. National Airspace System Delays as a Function of Next Generation Air Transportation System Airspace Capacity

    NASA Technical Reports Server (NTRS)

    Smith, Jerry; Viken, Jeff; Dollyhigh, Samuel; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

    2007-01-01

    This paper presents the results from a study which investigates the potential effects of the growth in air traffic demand including projected Very Light Jet (VLJ) air-taxi operations adding to delays experienced by commercial passenger air transportation in the year 2025. The geographic region studied is the contiguous United States (U.S.) of America, although international air traffic to and from the U.S. is included. The main focus of this paper is to determine how much air traffic growth, including VLJ air-taxi operations will add to enroute airspace congestion and determine what additional airspace capacity will be needed to accommodate the expected demand. Terminal airspace is not modeled and increased airport capacity is assumed.

  2. Taxiing, Take-Off, and Landing Simulation of the High Speed Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Reaves, Mercedes C.; Horta, Lucas G.

    1999-01-01

    The aircraft industry jointly with NASA is studying enabling technologies for higher speed, longer range aircraft configurations. Higher speeds, higher temperatures, and aerodynamics are driving these newer aircraft configurations towards long, slender, flexible fuselages. Aircraft response during ground operations, although often overlooked, is a concern due to the increased fuselage flexibility. This paper discusses modeling and simulation of the High Speed Civil Transport aircraft during taxiing, take-off, and landing. Finite element models of the airframe for various configurations are used and combined with nonlinear landing gear models to provide a simulation tool to study responses to different ground input conditions. A commercial computer simulation program is used to numerically integrate the equations of motion and to compute estimates of the responses using an existing runway profile. Results show aircraft responses exceeding safe acceptable human response levels.

  3. Shuttle Endeavour Mated to 747 SCA Taxi to Runway for Delivery to Kennedy Space Center, Florida

    NASA Image and Video Library

    1991-05-02

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, taxies to the runway to begin the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters.

  4. The Detection of Transport Land-Use Data Using Crowdsourcing Taxi Trajectory

    NASA Astrophysics Data System (ADS)

    Ai, T.; Yang, W.

    2016-06-01

    This study tries to explore the question of transport land-use change detection by large volume of vehicle trajectory data, presenting a method based on Deluanay triangulation. The whole method includes three steps. The first one is to pre-process the vehicle trajectory data including the point anomaly removing and the conversion of trajectory point to track line. Secondly, construct Deluanay triangulation within the vehicle trajectory line to detect neighborhood relation. Considering the case that some of the trajectory segments are too long, we use a interpolation measure to add more points for the improved triangulation. Thirdly, extract the transport road by cutting short triangle edge and organizing the polygon topology. We have conducted the experiment of transport land-use change discovery using the data of taxi track in Beijing City. We extract not only the transport land-use area but also the semantic information such as the transformation speed, the traffic jam distribution, the main vehicle movement direction and others. Compared with the existed transport network data, such as OpenStreet Map, our method is proved to be quick and accurate.

  5. Lévy-taxis: a novel search strategy for finding odor plumes in turbulent flow-dominated environments

    NASA Astrophysics Data System (ADS)

    Pasternak, Zohar; Bartumeus, Frederic; Grasso, Frank W.

    2009-10-01

    Locating chemical plumes in aquatic or terrestrial environments is important for many economic, conservation, security and health related human activities. The localization process is composed mainly of two phases: finding the chemical plume and then tracking it to its source. Plume tracking has been the subject of considerable study whereas plume finding has received little attention. We address here the latter issue, where the searching agent must find the plume in a region often many times larger than the plume and devoid of the relevant chemical cues. The probability of detecting the plume not only depends on the movements of the searching agent but also on the fluid mechanical regime, shaping plume intermittency in space and time; this is a basic, general problem when exploring for ephemeral resources (e.g. moving and/or concealing targets). Here we present a bio-inspired search strategy named Lévy-taxis that, under certain conditions, located odor plumes significantly faster and with a better success rate than other search strategies such as Lévy walks (LW), correlated random walks (CRW) and systematic zig-zag. These results are based on computer simulations which contain, for the first time ever, digitalized real-world water flow and chemical plume instead of their theoretical model approximations. Combining elements of LW and CRW, Lévy-taxis is particularly efficient for searching in flow-dominated environments: it adaptively controls the stochastic search pattern using environmental information (i.e. flow) that is available throughout the course of the search and shows correlation with the source providing the cues. This strategy finds natural application in real-world search missions, both by humans and autonomous robots, since it accomodates the stochastic nature of chemical mixing in turbulent flows. In addition, it may prove useful in the field of behavioral ecology, explaining and predicting the movement patterns of various animals searching for

  6. Orbital Transfer Vehicle (space taxi) with aerobraking at Earth and Mars

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This report shall cover all major aspects of the design of an Aeroassisted Manned Transfer Vehicle (or TAXI) for use as part of advanced manned Mars missions based on a cycling ship concept. Along with the heliocentric orbiting Cycling Spacecraft, such a TAXI would be a primary component of a long-term transportation system for Mars exploration. The Aeroassisted Manned Transfer Vehicle (AMTV) design developed shall operate along transfer trajectories between Earth and a Cycling Spacecraft (designed by the University of Michigan) and Mars. All operations of the AMTV shall be done primarily within the sphere of influence of the two planets. Maximum delta-V's for the vehicle have been established near 9 km/sec, with transfer durations of about 3 days. Acceleration deltaV's will be accomplished using 3 SSME-based hydrogen-oxygen chemical rockets (l(sub sp) = 485 sec & Thrust greater than = 300,00 Ib(sub f)/engine) with a thrust vector directly opposite the aerobraking deceleration vector. The aerobraking deceleration portion of an AMTV mission would be accomplished in this design by a moderate L/D aeroshield of an ellipsoidally-blunt, raked-off, elliptic cone (EBROEC) shape. The reusable thermal protection material comprising the shield will consist of a flexible, multi-layer, ceramic fabric stretched over a lightweight, rigid, shape - defining truss structure. Behind this truss, other components, including the engine supports, would be attached and protected from heating during aerobraking passes. Among these other components would be 2 LOX tanks and 4 LH2 tanks (and their support frames) holding over 670,000 lbm of propellant necessary to impart the required delta-V to the 98,000 lbm burnout mass vehicle. A 20,000 lbm crew module with docking port (oriented parallel to the accel./decel. axis) will provide accommodations for 9 crew members (11 under extreme conditions) for durations up to seven days, thus allowing extra time for emergency situations. This AMTV will be

  7. Collective Human Mobility Pattern from Taxi Trips in Urban Area

    PubMed Central

    Peng, Chengbin; Jin, Xiaogang; Wong, Ka-Chun; Shi, Meixia; Liò, Pietro

    2012-01-01

    We analyze the passengers' traffic pattern for 1.58 million taxi trips of Shanghai, China. By employing the non-negative matrix factorization and optimization methods, we find that, people travel on workdays mainly for three purposes: commuting between home and workplace, traveling from workplace to workplace, and others such as leisure activities. Therefore, traffic flow in one area or between any pair of locations can be approximated by a linear combination of three basis flows, corresponding to the three purposes respectively. We name the coefficients in the linear combination as traffic powers, each of which indicates the strength of each basis flow. The traffic powers on different days are typically different even for the same location, due to the uncertainty of the human motion. Therefore, we provide a probability distribution function for the relative deviation of the traffic power. This distribution function is in terms of a series of functions for normalized binomial distributions. It can be well explained by statistical theories and is verified by empirical data. These findings are applicable in predicting the road traffic, tracing the traffic pattern and diagnosing the traffic related abnormal events. These results can also be used to infer land uses of urban area quite parsimoniously. PMID:22529917

  8. Autonomous taxis could greatly reduce greenhouse-gas emissions of US light-duty vehicles

    NASA Astrophysics Data System (ADS)

    Greenblatt, Jeffery B.; Saxena, Samveg

    2015-09-01

    Autonomous vehicles (AVs) are conveyances to move passengers or freight without human intervention. AVs are potentially disruptive both technologically and socially, with claimed benefits including increased safety, road utilization, driver productivity and energy savings. Here we estimate 2014 and 2030 greenhouse-gas (GHG) emissions and costs of autonomous taxis (ATs), a class of fully autonomous shared AVs likely to gain rapid early market share, through three synergistic effects: (1) future decreases in electricity GHG emissions intensity, (2) smaller vehicle sizes resulting from trip-specific AT deployment, and (3) higher annual vehicle-miles travelled (VMT), increasing high-efficiency (especially battery-electric) vehicle cost-effectiveness. Combined, these factors could result in decreased US per-mile GHG emissions in 2030 per AT deployed of 87-94% below current conventionally driven vehicles (CDVs), and 63-82% below projected 2030 hybrid vehicles, without including other energy-saving benefits of AVs. With these substantial GHG savings, ATs could enable GHG reductions even if total VMT, average speed and vehicle size increased substantially. Oil consumption would also be reduced by nearly 100%.

  9. Reactivation of latent herpes viruses in cosmonauts during a soyuz taxi mission

    NASA Astrophysics Data System (ADS)

    Mehta, Satish K.; Pierson, Duane L.

    2007-09-01

    The hypothesis tested by this project is that space flight increases the incidence and duration of herpes virus reactivation and shedding in saliva. Saliva, urine, and blood samples were collected from 3 crew members who participated in a 14-day Odessa Soyuz taxi mission. Saliva samples were collected before, during, and after the mission, and blood and urine were collected before and after the mission. The saliva and urine samples were analyzed using the polymerase chain reaction to detect the presence of 3 important herpes viruses. Epstein-Barr virus (EBV) and varicella-zoster virus (VZV) were tested in saliva, and cytomegalovirus (CMV) was measured in urine samples. Plasma antibodies levels to these viruses were determined by enzyme-linked immunosorbent assay before and after flight. EBV reactivated before, during, and after flight; CMV reactivated before and after flight; and VZV reactivated during and after flight. In other studies, greater frequencies of positive samples and greater numbers of copies of viral DNA have been found. No increases in titer of antibodies to these viruses were found, suggesting that an immune response may not be necessary for reactivation.

  10. Survey of health and licensing policies for taxi drivers in Singapore, Hong Kong and Australia: a perspective from evidence on older drivers.

    PubMed

    Chan, M L; Gustafsson, L; Liddle, J

    2010-12-01

    With an ageing population, policy makers need to balance active ageing needs with older driver safety. In 2009, a survey of licensing policies for taxi drivers in Singapore, Hong Kong and Australia was undertaken for an evidence-based review of policies. Licensing requirements collected using semi-structured questionnaires were compared descriptively and with evidence from licensing policies on older drivers. All the regions used medical certifications with vision screening. The frequency of medical certification varied according to the renewal cycle and age. Medical guidelines on fitness to drive were available in Australia and Singapore. Legislation for self-reporting of medical conditions by drivers existed in Australia and Hong Kong. Legislation for reporting at-risk drivers by doctors was limited to two Australian states. There were differences in the minimum age and driving experience criteria, the use of practical training, written and English tests, age-based screening, mandatory retirement age, refresher courses, off- and on-road tests. Medical screening for at-risk drivers remains crucial. Age-based mandatory retirement policy at 73 years in Singapore is contrary to evidence-based practice. The lack of legislation for self-reporting of illness by drivers, the high minimum age criteria and therapy driving assessments for healthy taxi drivers are also unique to Singapore. There was stricter age-based relicensing from the age of 65 years in some Australian states and in Singapore. Continuing education for doctors, multi-tier screening for at-risk drivers and licensing policy changes are indicated.

  11. [Comparative life cycle environmental assessment between electric taxi and gasoline taxi in Beijing].

    PubMed

    Shi, Xiao-Qing; Sun, Zhao-Xin; Li, Xiao-Nuo; Li, Jin-Xiang; Yang, Jian-Xin

    2015-03-01

    Tailpipe emission of internal combustion engine vehicle (ICEV) is one of the main sources leading to atmospheric environmental problems such as haze. Substituting electric vehicles for conventional gasoline vehicles is an important solution for reducing urban air pollution. In 2011, as a pilot city of electric vehicle, Beijing launched a promotion plan of electric vehicle. In order to compare the environmental impacts between Midi electric vehicle (Midi EV) and Hyundai gasoline taxi (ICEV), this study created an inventory with local data and well-reasoned assumptions, and contributed a life cycle assessment (LCA) model with GaBi4.4 software and comparative life cycle environmental assessment by Life cycle impact analysis models of CML2001(Problem oriented) and EI99 (Damage oriented), which included the environmental impacts of full life cycle, manufacture phase, use phase and end of life. The sensitivity analysis of lifetime mileage and power structure was also provided. The results indicated that the full life cycle environmental impact of Midi EV was smaller than Hyundai ICEV, which was mainly due to the lower fossil fuel consumption. On the contrary, Midi EV exhibited the potential of increasing the environmental impacts of ecosystem quality influence and Human health influence. By CML2001 model, the results indicated that Midi EV might decrease the impact of Abiotic Depletion Potential, Global Warming Potential, Ozone Layer Depletion Potential and so on. However, in the production phase, the impact of Abiotic Depletion Potential, Acidification Potential, Eutrophication Potential, Global Warming Potential, Photochemical Ozone Creation Potential, Ozone Layer Depletion Potential, Marine Aquatic Ecotoxicity Potential, Terrestric Ecotoxicity Potential, Human Toxicity Potential of Midi EV were increased relative to Hyundai ICEV because of emissions impacts from its power system especially the battery production. Besides, in the use phase, electricity production was

  12. Perseus Taxi

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Perseus proof-of-concept vehicle is seen here as it taxis on Rogers Dry Lake, adjacent the Dryden Flight Research Center, Edwards, California. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus design, which began with the Perseus Proof-Of-Concept aircraft. Perseus was initially developed as part of NASA's Small High-Altitude Science Aircraft (SHASA) program, which later evolved into the ERAST project. The

  13. TaxI: a software tool for DNA barcoding using distance methods

    PubMed Central

    Steinke, Dirk; Vences, Miguel; Salzburger, Walter; Meyer, Axel

    2005-01-01

    DNA barcoding is a promising approach to the diagnosis of biological diversity in which DNA sequences serve as the primary key for information retrieval. Most existing software for evolutionary analysis of DNA sequences was designed for phylogenetic analyses and, hence, those algorithms do not offer appropriate solutions for the rapid, but precise analyses needed for DNA barcoding, and are also unable to process the often large comparative datasets. We developed a flexible software tool for DNA taxonomy, named TaxI. This program calculates sequence divergences between a query sequence (taxon to be barcoded) and each sequence of a dataset of reference sequences defined by the user. Because the analysis is based on separate pairwise alignments this software is also able to work with sequences characterized by multiple insertions and deletions that are difficult to align in large sequence sets (i.e. thousands of sequences) by multiple alignment algorithms because of computational restrictions. Here, we demonstrate the utility of this approach with two datasets of fish larvae and juveniles from Lake Constance and juvenile land snails under different models of sequence evolution. Sets of ribosomal 16S rRNA sequences, characterized by multiple indels, performed as good as or better than cox1 sequence sets in assigning sequences to species, demonstrating the suitability of rRNA genes for DNA barcoding. PMID:16214755

  14. NASA's space shuttle Atlantis and its 747 carrier taxied on the Edwards Air Force Base flightline as the unusual combination left for Kennedy Space Center, Florida, on March 1, 2001

    NASA Image and Video Library

    2001-03-01

    NASA's space shuttle Atlantis and its 747 carrier taxied on the Edwards Air Force Base flightline as the unusual combination left for Kennedy Space Center, Florida, on March 1, 2001. Atlantis and the shuttle Columbia were both airborne on the same day as they migrated from California to Florida. Columbia underwent refurbishing at nearby Palmdale, California.

  15. Human Mars Mission: SEP Architecture Crew Taxi Propulsion Stage Study and Design and Technology for Reaction and Control System. Part 1

    NASA Technical Reports Server (NTRS)

    Young, Archie

    1999-01-01

    The Mars exploration is a candidate pathway to expand human presence and useful activities in the solar system. There are several propulsion system options being considered to place the Mars payload on its inter-planetary transfer trajectory. One propulsion option is the use of Solar Electric Propulsion (SEP) to spiral out with the Mars payload from an initial Low Earth Orbit (LEO) to an elliptical High Earth Orbit (HEO). This report, presented in annotated facing page format, describes the work completed on the design of a crew taxi propulsion stage used in conjunction with the SEP. Transportation system/mission analysis topics covered in this report include sub-system analysis, trajectory profile description, mass performance and crew taxi stage sizing, stage configuration, stage cost, and Trans-Mars Injection (TMI) launch window. The high efficiency of SEP is used to provide the major part of the TMI propulsion maneuver. Orbital energy is continuously added over a period of approximately twelve months. The SEP and Mars payload follow a spiral trajectory from an initial LEO to a final elliptical HEO. A small chemical stage is then used to provide the final part of the TMI. The now unloaded SEP returns to LEO to repeat another spiral trajectory with payload to HEO. The spiral phase of the SEP's trajectory takes several months to reach HEO, thus significantly increasing the exposure time of the crew to zero-gravity. In order to minimize the long zero-gravity effects, a high thrust chemical stage delivers the crew to the SEP's HEO. The crew rendezvous with the Mars payload in HEO. After a checkout period the Mars payload with the crew is injected onto a Trans-Mars Trajectory by a small chemical stage.

  16. Human Mars Mission: SEP Architecture, Crew Taxi Propulsion Stage Study and Design and Technology for Reaction and Control System. Pt. 1

    NASA Technical Reports Server (NTRS)

    Young, Archie

    1999-01-01

    The Mars exploration is a candidate pathway to expand human presence and useful activities in the solar system. There are several propulsion system options being considered to place the Mars payload on its interplanetary transfer trajectory. One propulsion option is the use of Solar Electric Propulsion (SEP) to spiral out with the Mars payload from an initial Low Earth Orbit (LEO) to an elliptical High Earth Orbit (HEO). This report, presented in annotated facing page format, describes the work completed on the design of a crew taxi propulsion stage used in conjunction with the SEP. Transportation system/mission analysis topics covered in this report include sub-system analysis, trajectory profile description, mass performance and crew taxi stage sizing, stage configuration, stage cost, and Trans-Mars Injection (TMI) launch window. The high efficiency of SEP is used to provide the major part of the TMI propulsion maneuver. Orbital energy is continuously added over a period of approximately twelve months. The SEP and Mars payload follow a spiral trajectory from an initial LEO to a final elliptical HEO. A small chemical stage is then used to provide the final part of the TMI. The now unloaded SEP returns to LEO to repeat another spiral trajectory with payload to HEO. The spiral phase of the SEP's trajectory takes several months to reach HEO, thus significantly increasing the exposure time of the crew to zero-gravity. In order to minimize the long zero-gravity effects, a high thrust chemical stage delivers the crew to the SEP's HEO. The crew rendezvous with the Mars payload in HEO. After a checkout period the Mars payload with the crew is injected onto a Trans-Mars Trajectory by a small chemical stage.

  17. Driving performance changes of middle-aged experienced taxi drivers due to distraction tasks during unexpected situations.

    PubMed

    Kim, Hyung-Sik; Choi, Mi-Hyun; Choi, Jin-Seung; Kim, Hyun-Joo; Hong, Sang-Pyo; Jun, Jae-Hoon; Tack, Gye-Rae; Kim, Boseong; Min, Ung-Chan; Lim, Dae-Woon; Chung, Soon-Cheol

    2013-10-01

    This study investigated the effects of distraction taskssuch as sending a text message with a cellphone and searching navigation with car navigation system-on the driving performance of 29 highly experienced taxi drivers in their 50s. All participants were instructed to drive using a driving simulator for 2 min. while maintaining a constant distance from the vehicle in front and a constant speed. Participants drove without any distractions for the first minute. For an additional minute, they performed Driving Only or performed a task while driving (Driving + Sending Text Message or Driving + Searching Navigation). An unexpected situation, in which the participant had to stop abruptly due to a sudden stop of the preceding vehicle, occurred during this period. Driving performance during the unexpected situation was evaluated by car control variables, medial-lateral coefficient of variation and brake time, and by motion variables such as the jerk-cost function. Compared to Driving Only, jerk-cost function, medial-lateral coefficient of variation, and brake time increased during Driving + Sending Text Message or Driving + Searching Navigation.

  18. NO and NO2 emission ratios measured from in-use commercial aircraft during taxi and takeoff.

    PubMed

    Herndon, Scott C; Shorter, Joanne H; Zahniser, Mark S; Nelson, David D; Jayne, John; Brown, Robert C; Miake-Lye, Richard C; Waitz, Ian; Silva, Phillip; Lanni, Thomas; Demerjian, Ken; Kolb, Charles E

    2004-11-15

    In August 2001, the Aerodyne Mobile Laboratory simultaneously measured NO, NO2, and CO2 within 350 m of a taxiway and 550 m of a runway at John F. Kennedy Airport. The meteorological conditions were such that taxi and takeoff plumes from individual aircraft were clearly resolved against background levels. NO and NO2 concentrations were measured with 1 s time resolution using a dual tunable infrared laser differential absorption spectroscopy instrument, utilizing an astigmatic multipass Herriott cell. The CO2 measurements were also obtained at 1 s time resolution using a commercial non-dispersive infrared absorption instrument. Plumes were measured from over 30 individual planes, ranging from turbo props to jumbo jets. NOx emission indices were determined by examining the correlation between NOx (NO + NO2) and CO2 during the plume measurements. Several aircraft tail numbers were unambiguously identified, allowing those specific airframe/engine combinations to be determined. The resulting NOx emission indices from positively identified in-service operating airplanes are compared with the published International Civil Aviation Organization engine certification test database collected on new engines in certification test cells.

  19. Taxi driver training in Madagascar: the first step in developing a functioning prehospital emergency care system.

    PubMed

    Geduld, Heike; Wallis, Lee

    2011-09-01

    Prehospital care in developing countries is severely lacking. Few countries can afford the relatively expensive formalised Western model of a prehospital emergency medical system. The WHO has highlighted the development of layperson first responder programmes as the most basic step in the development of a functioning prehospital system. To describe the first training programme of its kind, run in Mahajanga, Madagascar. The faculty was invited by Mahajanga Medical School. Local input was taken into account in developing the curriculum. 26 taxi drivers were invited to attend in cooperation with the local municipality. The faculty consisted of five instructors from the Division of Emergency Medicine and EMSSA, plus local doctors from University Hospital Mahajanga. The 1-day course included workshops on prehospital scene management, bleeding and broken bones, immobilisation and patient movement, and labour and delivery. The workshops made use of commonly available items only including packets, string and towels; French and Malagasy translators were available throughout. Both faculty and candidates deemed the course a success and plans for formal evaluation of knowledge and skill retention are underway. Future plans are to continue the training using local instructors and in rural districts.

  20. Factors associated with HIV testing among male motorbike taxi drivers in urban Vietnam.

    PubMed

    Huy, Nguyen Van; Khuyen, Le Thi; Ha, Pham Nguyen

    2015-01-01

    Using the Attitude-Skills-Knowledge (ASK) model, this study examined the prevalence of, and factors associated with, human immunodeficiency virus (HIV) testing among male motorbike taxi drivers (MMTDs). In a cross-sectional design, using quantitative approaches, 291 MMTDs were recruited from 135 sites across 13 districts in Hanoi, Vietnam, for a face-to-face interview. Applying the ASK model modified as a central theory, logistic regression was used to identify determinants of HIV testing. Although many MMTDs engaged in multiple risk behaviours for HIV, only 20.6% had been tested for HIV during the past 12 months. The tested model included one factor of the ASK model, HIV prevention knowledge (adjusted odds ratio [AOR] = 4.76; 95% confidence interval [CI] = 2.12-10.7) and five additional factors: being married (AOR = 3.13; 95% CI = 1.25-4.78), preferring sex with men or with both men and women (AOR = 8.72; 95% CI = 1.48-51.5), having lower number of lifetime sex partners (AOR = 0.66; 95% CI = 0.49-0.88), higher number of past year sex partners (AOR = 2.97: 95% CI = 1.21-7.31) and discussing condom use when having sex with partners (AOR = 0.08; 95% CI = 0.01-7.31). This modified ASK model provided better fit than the ASK model, as it explained more variance in HIV testing (47 vs. 29.8%). Recognising factors associated with HIV testing among MMTDs enables us to create suitable public health intervention strategies.

  1. Myocardial infarction among male bus, taxi, and lorry drivers in middle Sweden.

    PubMed Central

    Gustavsson, P; Alfredsson, L; Brunnberg, H; Hammar, N; Jakobsson, R; Reuterwall, C; Ostlin, P

    1996-01-01

    OBJECTIVES: The aim of the present case-referent study was to investigate the incidence of myocardial infarction among male professional drivers, taking the type of vehicles and area of residence into account. METHODS: The study base comprised all men aged 30-74 in five counties in middle Sweden during 1976-81 or 1976-84. Incident cases of the first episode of myocardial infarction were identified from registers of hospital admissions and causes of deaths. Referents were selected randomly from the study base. Information about occupation was obtained from the national censuses in 1970 and 1975. The possible impact from tobacco smoking and overweight were evaluated by simulations in combination with indirect data on these factors. RESULTS: The incidence of myocardial infarction was increased among bus drivers in Stockholm (relative risk (RR) = 1.53, 95% confidence interval (95% CI) 1.15-2.05), and among taxi drivers both in Stockholm (RR 1.65, 95% CI 1.30-2.11) and in the surrounding rural counties (RR 1.82, 95% CI 1.17-2.82). A smaller increase was found among long distance lorry drivers, whereas the relative risk among short distance lorry drivers was close to unity. Indirect comparisons make it unlikely that the excess among bus drivers in Stockholm could be explained by uncontrolled confounding from tobacco smoking or overweight. A very high proportion (more than 80%) of urban bus drivers in Sweden report a combination of high psychological demands and low control at work. CONCLUSIONS: Different types of drivers are at different risk of myocardial infarction. Bus drivers in urban areas seem to be at an increased risk, which is unlikely to be explained by uncontrolled confounding from tobacco smoking or overweight. Psychosocial work conditions may play a part in the increased incidence of myocardial infarction among urban bus drivers and should be investigated further. PMID:8664960

  2. X-36 Tailless Fighter Agility Research Aircraft on lakebed during high-speed taxi tests

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA/McDonnell Douglas Corporation (MDC) X-36 Tailless Fighter Agility Research Aircraft undergoes high-speed taxi tests on Rogers Dry Lake at NASA Dryden Flight Research Center, Edwards, California, on October 17, 1996. The aircraft was tested at speeds up to 85 knots. Normal takeoff speed would be 110 knots. More taxi and radio frequency tests were slated before it's first flight would be made. This took place on May 17, 1997. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems

  3. Centurion Quarter-scale Prototype Pre-flight Taxi Test

    NASA Technical Reports Server (NTRS)

    1997-01-01

    As crewmen jog and cycle alongside, a battery-powered, quarter-scale prototype of the remotely-piloted Centurion flying wing rolls across the El Mirage Dry Lake during pre-flight taxi tests. Centurion was a unique remotely piloted, solar-powered airplane developed under NASA's Environmental Research Aircraft and Sensor (ERAST) Program at the Dryden Flight Research Center, Edwards, California. Dryden joined with AeroVironment, Inc., Monrovia, California, under an ERAST Joint Sponsored Research Agreement, to design, develop, manufacture, and conduct flight development tests for the Centurion. The airplane was believed to be the first aircraft designed to achieve sustained horizontal flight at altitudes of 90,000 to 100,000 feet. Achieving this capability would meet the ERAST goal of developing an ultrahigh-altitude airplane that could meet the needs of the science community to perform upper-atmosphere environmental data missions. Much of the technology leading to the Centurion was developed during the Pathfinder and Pathfinder-Plus projects. However, in the course of its development, the Centurion became a prototype technology demonstration aircraft designed to validate the technology for the Helios, a planned future high-altitude, solar-powered aircraft that could fly for weeks or months at a time on science or telecommunications missions. Centurion had 206-foot-long wings and used batteries to supply power to the craft's 14 electric motors and electronic systems. Centurion first flew at Dryden Nov. 10, 1998, and followed up with a second test flight Nov. 19. On its third and final flight on Dec. 3, the craft was aloft for 31 minutes and reached an altitude of about 400 feet. All three flights were conducted over a section of Rogers Dry Lake adjacent to Dryden. For its third flight, the Centurion carried a simulated payload of more than 600 pounds--almost half the lightweight aircraft's empty weight. John Del Frate, Dryden's project manager for solar

  4. Isolation, Purification, and Identification of Taxol and Related Taxanes from Taxol-Producing Fungus Aspergillus niger subsp. taxi.

    PubMed

    Li, Dan; Fu, Dongwei; Zhang, Yue; Ma, Xueling; Gao, Liguo; Wang, Xioahua; Zhou, Dongpo; Zhao, Kai

    2017-08-28

    The content of taxol in the bark of yews is very low, and this is not affordable from the environmental point of view. Thus, it is a necessity to look for alternative sources of taxol production to solve its supply. Currently, a large portion of the taxol in the market comes from chemical semi-synthesis, but the semi-synthetic precursors such as baccatin III and 10-deacetyl-baccatin III are extracted from needles and twigs of yew trees. Taxol-producing fungi as a renewable resource is a very promising way to increase the scale of taxol production. Our group has obtained a taxol-producing endophytic fungus, Aspergillus niger subsp. taxi HD86-9, to examine if A. niger can produce the taxanes. Six compounds from the fermentation broth of strain HD86-9 were isolated and identified by 1 H NMR, 13 C NMR, and ESI-MS. The results showed that the six compounds included four taxane diterpenoids (taxol, cephalomannine, baccatin III, and 10-deacetyl-baccatin III) and two non-taxane compounds (β-sitosterol and flavonoid isovitexin). The study verified that the taxanes can be produced by the A. niger , which is very important to taxol production via chemical semi-synthesis. Additionally, the finding is potentially very significant to solve the taxol semi-synthetic precursors extracted from needles and twigs of yew trees, and the precursor production can be easily increased through the culture condition optimization, genetic breeding, and metabolic engineering of the A. niger .

  5. Step On It! Impact of a Workplace New York City Taxi Driver Health Intervention to Increase Necessary Health Care Access

    PubMed Central

    Gany, Francesca; Bari, Sehrish; Gill, Pavan; Loeb, Rebecca

    2015-01-01

    Objectives. We describe the impact of the Step On It! intervention to link taxi drivers, particularly South Asians, to health insurance enrollment and navigate them into care when necessary. Methods. Step On It! was a worksite initiative held for 5 consecutive days from September 28 to October 2, 2011, at John F. Kennedy International Airport in New York City. Data collected included sociodemographics, employment, health care access and use, height, weight, blood pressure, and random plasma glucose. Participants were given their results, counseled by a medical professional, and invited to participate in free workshops provided by partner organizations. Results. Of the 466 drivers participated, 52% were uninsured, and 49% did not have a primary care provider. Of 384 drivers who had blood pressure, glucose, or both measured, 242 (63%) required urgent or regular follow-up. Of the 77 (32%) requiring urgent follow-up, 50 (65%) sought medical care at least once, of whom 13 (26%) received a new diagnosis. Of the 165 (68%) requiring regular follow-up, 68 (41%) sought medical care at least once, of whom 5 (7%) received a new diagnosis. Conclusions. This study provides encouraging results about the potential impact of an easy-to-deliver, easily scalable workplace intervention with a large, vulnerable population. PMID:25211738

  6. SR-71 - Taxi on Ramp with Engines

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This photo shows a head-on shot of NASA's SR-71A aircraft taxiing on the ramp at NASA's Dryden Flight Research Center, Edwards, California, heat waves from its engines blurring the hangars in the background. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used for the Linear Aerospike Rocket Engine, or LASRE Experiment. Another earlier project consisted of a series of flights using the SR-71 as a science camera platform for NASA's Jet Propulsion Laboratory in Pasadena

  7. 14 CFR 205.5 - Minimum coverage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... commuter air carriers but excluding U.S. air taxi operators and Canadian charter air taxi operators, shall...,000 times 75 percent of the number of passenger seats installed in the aircraft. (c) U.S. air taxi... each occurrence for loss of or damage to property. (2) U.S. air taxi operators carrying passengers in...

  8. 14 CFR 205.5 - Minimum coverage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... commuter air carriers but excluding U.S. air taxi operators and Canadian charter air taxi operators, shall...,000 times 75 percent of the number of passenger seats installed in the aircraft. (c) U.S. air taxi... each occurrence for loss of or damage to property. (2) U.S. air taxi operators carrying passengers in...

  9. 14 CFR 298.24 - Cancellation of the registration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.24 Cancellation of the registration. The registration of an air taxi...

  10. 14 CFR 298.24 - Cancellation of the registration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.24 Cancellation of the registration. The registration of an air taxi...

  11. A Visit to Taxicab Geometry

    ERIC Educational Resources Information Center

    Hanson, J. R.

    2012-01-01

    The taxi metric is introduced, compared to the Euclidean metric, and used to define the taxi circle. For all pairs of points "A" and "B" the set of points equally distant under the taxi metric to "A" and to "B" is determined. For any triangle these sets are used to either find the centre of a taxi circle that can circumscribe the triangle or to…

  12. Assessment of Urban Aerial Taxi with Cryogenic Components Under Design Environment for Novel Vertical Lift Vehicles (DELIVER)

    NASA Technical Reports Server (NTRS)

    Snyder, Christopher

    2017-01-01

    Assessing the potential to bring 100 years of aeronautics knowledge to the entrepreneurs desktop to enable a design environment for emerging vertical lift vehicles is one goal for the NASA's Design Environment for Novel Vertical Lift Vehicles (DELIVER). As part of this effort, a system study was performed using a notional, urban aerial taxi system to better understand vehicle requirements along with the tools and methods capability to assess these vehicles and their subsystems using cryogenic cooled components. The baseline was a vertical take-off and landing (VTOL) aircraft, with all-electric propulsion system assuming 15 year technology performance levels and its capability limited to a pilot with one or two people and cargo. Hydrocarbon-fueled hybrid concepts were developed to improve mission capabilities. The hybrid systems resulted in significant improvements in maximum range and number of on demand mobility (ODM) missions that could be completed before refuel or recharge. An important consideration was thermal management, including the choice for air-cooled or cryogenic cooling using liquid natural gas (LNG) fuel. Cryogenic cooling for critical components can have important implications on component performance and size. Thermal loads were also estimated, subsequent effort will be required to verify feasibility for cooling airflow and packaging. LNG cryogenic cooling of selected components further improved vehicle range and reduced thermal loads, but the same concerns for airflow and packaging still need to be addressed. The use of the NASA Design and Analysis of Rotorcraft (NDARC) tool for vehicle sizing and mission analysis appears to be capable of supporting analyses for present and future types of vehicles, missions, propulsion, and energy sources. Further efforts are required to develop verified models for these new types of propulsion and energy sources in the size and use envisioned for these emerging vehicle and mission classes.

  13. Assessment of Urban Aerial Taxi with Cryogenic Components under Design Environment for Novel Vertical Lift Vehicles (DELIVER)

    NASA Technical Reports Server (NTRS)

    Snyder, Christopher A.

    2017-01-01

    Assessing the potential to bring 100 years of aeronautics knowledge to the entrepreneurs desktop to enable a design environment for emerging vertical lift vehicles is one goal for the NASAs Design Environment for Novel Vertical Lift Vehicles (DELIVER). As part of this effort, a system study was performed using a notional, urban aerial taxi system to better understand vehicle requirements along with the tools and methods capability to assess these vehicles and their subsystems using cryogenic cooled components. The baseline was a vertical take-off and landing (VTOL) aircraft, with all-electric propulsion system assuming 15 year technology performance levels and its capability limited to a pilot with one or two people and cargo. Hydrocarbon-fueled hybrid concepts were developed to improve mission capabilities. The hybrid systems resulted in significant improvements in maximum range and number of on demand mobility (ODM) missions that could be completed before refuel or recharge. An important consideration was thermal management, including the choice for air-cooled or cryogenic cooling using liquid natural gas (LNG) fuel. Cryogenic cooling for critical components can have important implications on component performance and size. Thermal loads were also estimated, subsequent effort will be required to verify feasibility for cooling airflow and packaging. LNG cryogenic cooling of selected components further improved vehicle range and reduced thermal loads, but the same concerns for airflow and packaging still need to be addressed. The use of the NASA Design and Analysis of Rotorcraft (NDARC) tool for vehicle sizing and mission analysis appears to be capable of supporting analyses for present and future types of vehicles, missions, propulsion, and energy sources. Further efforts are required to develop verified models for these new types of propulsion and energy sources in the size and use envisioned for these emerging vehicle and mission classes.

  14. Engineering Safety- and Security-Related Requirements for Software-Intensive Systems

    DTIC Science & Technology

    2007-05-31

    University Very Large New Zoo Parking Lots Zoo Back Lots Restaurants and Shops Tropical Rainforest African SavannaChildren’s Petting Area Monkeys Great Apes...decide to ride to the Great Apes and Monkeys taxi station near the central shops and restaurants area. Mr. Smith then swipes his zoo taxi travel card...taxi station on their right, circles around the central area, and soon pulls off the Zoo Loop Line to enter the inner Great Apes and Monkeys taxi

  15. 14 CFR 294.32 - Security arrangements for operating Public Charters.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.32 Security arrangements for operating Public Charters. When a Canadian charter air taxi... taxi operator shall meet the bonding or escrow requirements applicable to foreign air carriers as set...

  16. 14 CFR 294.32 - Security arrangements for operating Public Charters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.32 Security arrangements for operating Public Charters. When a Canadian charter air taxi... taxi operator shall meet the bonding or escrow requirements applicable to foreign air carriers as set...

  17. 14 CFR 294.20 - Applying for registration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Registration for Exemption § 294.20 Applying for registration. To apply for registration under this part, a Canadian charter air taxi operator... shall be certified by a responsible officer of the applicant Canadian charter air taxi operator...

  18. 14 CFR 294.20 - Applying for registration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Registration for Exemption § 294.20 Applying for registration. To apply for registration under this part, a Canadian charter air taxi operator... shall be certified by a responsible officer of the applicant Canadian charter air taxi operator...

  19. 14 CFR 298.30 - Public disclosure of policy on consumer protection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS... protection. (a) Every air taxi and commuter air carrier shall cause to be displayed continuously in a..., containing a statement setting forth the air taxi and commuter air carrier's policy on baggage liability and...

  20. 14 CFR 298.38 - Financial security arrangements for operating Public Charters.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER... security arrangements for operating Public Charters. When an air taxi operator or commuter air carrier performs a Public Charter under part 380 of this chapter, either: (a) The air taxi operator or commuter air...

  1. 14 CFR 298.23 - Notifications to the Department of change in operations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.23 Notifications to the Department of change in operations. (a) If any of the information contained on its registration changes, an air taxi...

  2. 14 CFR 294.1 - Applicability and purpose.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General § 294.1 Applicability and... taxi operators,” and establishes registration procedures for these carriers operating or seeking to... air taxi operators from certain provisions of the Subtitle VII of Title 49 of the United States Code...

  3. 14 CFR 298.38 - Financial security arrangements for operating Public Charters.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER... security arrangements for operating Public Charters. When an air taxi operator or commuter air carrier performs a Public Charter under part 380 of this chapter, either: (a) The air taxi operator or commuter air...

  4. 14 CFR 294.30 - Scope of service and equipment authorized.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for... air service, and the exemption provided by this part to Canadian charter air taxi operators that... charter air taxi operator shall not use large aircraft for charter air service until it has been granted a...

  5. 14 CFR 294.1 - Applicability and purpose.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General § 294.1 Applicability and... taxi operators,” and establishes registration procedures for these carriers operating or seeking to... air taxi operators from certain provisions of the Subtitle VII of Title 49 of the United States Code...

  6. 14 CFR 298.23 - Notifications to the Department of change in operations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.23 Notifications to the Department of change in operations. (a) If any of the information contained on its registration changes, an air taxi...

  7. 76 FR 72239 - Agency Information Collection Activities: Requests for Comments; Clearance of Renewed Approval of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... Air Taxi and Commuter Air Carrier Operations AGENCY: Federal Aviation Administration (FAA), DOT... certificate of public convenience and necessity from the DOT, with the exception of air taxi and commuter air...: OMB Control Number: 2120-0633. Title: Exemptions for Air Taxi and Commuter Air Carrier Operations...

  8. THE PROFITS AND PERILS OF PUBLICITY: ALLGEMEINE LITERATUR- ZEITUNG, THE THURN UND TAXIS POST, AND THE PERIODICAL TRADE AT THE END OF THE EIGHTEENTH CENTURY.

    PubMed

    Broman, Thomas

    2015-09-20

    Recent historiography on the growth of periodical publishing has emphasized newspapers and journals as constituents of an emergent communications system in early modern Europe. This system comprised the newspapers, journals and other publications that contributed its content, and also the postal systems that were the principal method of distributing that content. This article describes how the growth of this system in central Europe was supported in large measure by financial incentives that it offered to both constituents. First, in contrast with postal systems in France and the UK, the Thurn und Taxis Reichspost inserted itself as a middleman in the sale of periodicals, which gave the Reichspost an incentive to promote the trade. Second, the financial conditions for periodical publication made their costs depend more heavily on costs that were scalable to circulation than is true today, which resulted in the viability of publications with a lower circulation. The same cost structure also made it possible for certain prominent periodicals of the era to earn considerable profits for their publishers, as illustrated in this article by Allgemeine Literatur-Zeitung, which was published in Jena from 1785.

  9. The profits and perils of publicity: Allgemeine Literatur-Zeitung, the Thurn und Taxis Post, and the periodical trade at the end of the eighteenth century

    PubMed Central

    Broman, Thomas

    2015-01-01

    Recent historiography on the growth of periodical publishing has emphasized newspapers and journals as constituents of an emergent communications system in early modern Europe. This system comprised the newspapers, journals and other publications that contributed its content, and also the postal systems that were the principal method of distributing that content. This article describes how the growth of this system in central Europe was supported in large measure by financial incentives that it offered to both constituents. First, in contrast with postal systems in France and the UK, the Thurn und Taxis Reichspost inserted itself as a middleman in the sale of periodicals, which gave the Reichspost an incentive to promote the trade. Second, the financial conditions for periodical publication made their costs depend more heavily on costs that were scalable to circulation than is true today, which resulted in the viability of publications with a lower circulation. The same cost structure also made it possible for certain prominent periodicals of the era to earn considerable profits for their publishers, as illustrated in this article by Allgemeine Literatur-Zeitung, which was published in Jena from 1785. PMID:26495577

  10. 14 CFR 298.11 - Exemption authority.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Exemptions § 298.11 Exemption authority. Air taxi operators and commuter air carriers are hereby relieved from the following provisions of... imposed herein, and to the extent necessary to permit them to conduct air taxi or commuter air carrier...

  11. 14 CFR 298.11 - Exemption authority.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Exemptions § 298.11 Exemption authority. Air taxi operators and commuter air carriers are hereby relieved from the following provisions of... imposed herein, and to the extent necessary to permit them to conduct air taxi or commuter air carrier...

  12. 14 CFR 205.4 - Filing of evidence of insurance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... commuter air carriers and air taxi operators, and OST Form 6411 for foreign air carriers, including Canadian air taxi operators. The Department may return the certificate or self-insurance plan to the... Headquarters, AAL-230, 222 West 7th Avenue, Box 14, Anchorage, Alaska 99513. For Canadian air taxis, the forms...

  13. 14 CFR 205.4 - Filing of evidence of insurance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... commuter air carriers and air taxi operators, and OST Form 6411 for foreign air carriers, including Canadian air taxi operators. The Department may return the certificate or self-insurance plan to the... Headquarters, AAL-230, 222 West 7th Avenue, Box 14, Anchorage, Alaska 99513. For Canadian air taxis, the forms...

  14. 14 CFR 294.31 - Use of business name.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.31 Use of business name. (a) A Canadian charter air taxi operator, in holding out charter air service to the public and... this part. The Department may require a Canadian charter air taxi operator to change such names where...

  15. Anaerobic electron acceptor chemotaxis in Shewanella putrefaciens

    NASA Technical Reports Server (NTRS)

    Nealson, K. H.; Moser, D. P.; Saffarini, D. A.

    1995-01-01

    Shewanella putrefaciens MR-1 can grow either aerobically or anaerobically at the expense of many different electron acceptors and is often found in abundance at redox interfaces in nature. Such redox interfaces are often characterized by very strong gradients of electron acceptors resulting from rapid microbial metabolism. The coincidence of S. putrefaciens abundance with environmental gradients prompted an examination of the ability of MR-1 to sense and respond to electron acceptor gradients in the laboratory. In these experiments, taxis to the majority of the electron acceptors that S. putrefaciens utilizes for anaerobic growth was seen. All anaerobic electron acceptor taxis was eliminated by the presence of oxygen, nitrate, nitrite, elemental sulfur, or dimethyl sulfoxide, even though taxis to the latter was very weak and nitrate and nitrite respiration was normal in the presence of dimethyl sulfoxide. Studies with respiratory mutants of MR-1 revealed that several electron acceptors that could not be used for anaerobic growth nevertheless elicited normal anaerobic taxis. Mutant M56, which was unable to respire nitrite, showed normal taxis to nitrite, as well as the inhibition of taxis to other electron acceptors by nitrite. These results indicate that electron acceptor taxis in S. putrefaciens does not conform to the paradigm established for Escherichia coli and several other bacteria. Carbon chemo-taxis was also unusual in this organism: of all carbon compounds tested, the only positive response observed was to formate under anaerobic conditions.

  16. Health risk equations and risk assessment of airborne benzene homologues exposure to drivers and passengers in taxi cabins.

    PubMed

    Chen, Xiaokai; Feng, Lili; Luo, Huilong; Cheng, Heming

    2016-03-01

    Interior air environment and health problems of vehicles have attracted increasing attention, and benzene homologues (BHs) including benzene, toluene, ethylbenzene, xylenes, and styrene are primary hazardous gases in vehicular cabins. The BHs impact on the health of passengers and drivers in 38 taxis is assessed, and health risk equations of in-car BHs to different drivers and passengers are induced. The health risk of in-car BHs for male drivers is the highest among all different receptors and is 1.04, 6.67, and 6.94 times more than ones for female drivers, male passengers, and female passengers, respectively. In-car BHs could not lead to the non-cancer health risk to all passengers and drivers as for the maximal value of non-cancer indices is 0.41 and is less than the unacceptable value (1.00) of non-cancer health risk from USEPA. However, in-car BHs lead to cancer health risk to drivers as for the average value of cancer indices is 1.21E-04 which is 1.21 times more than the unacceptable value (1.00E-04) of cancer health risk from USEPA. Finally, for in-car airborne benzene concentration (X, μg/m(3)) to male drivers, female drivers, male passengers, and female passengers, the cancer health risk equations are Y = 1.48E-06X, Y = 1.42E-06X, Y = 2.22E-07X, and Y = 2.13E-07X, respectively, and the non-cancer health risk equations are Y = 1.70E-03X, Y = 1.63E-03X, Y = 2.55E-04X, and Y = 2.45E-04X, respectively.

  17. 14 CFR 298.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.2 Definitions. As used in this part: Air taxi operator means an air carrier as established by § 298.3(a). Air transportation..., 39 U.S.C. 5402, authorizes the carriage of mail by air taxi operators and commuter air carriers in...

  18. Quantifying the benefits of vehicle pooling with shareability networks

    PubMed Central

    Santi, Paolo; Resta, Giovanni; Szell, Michael; Sobolevsky, Stanislav; Strogatz, Steven H.; Ratti, Carlo

    2014-01-01

    Taxi services are a vital part of urban transportation, and a considerable contributor to traffic congestion and air pollution causing substantial adverse effects on human health. Sharing taxi trips is a possible way of reducing the negative impact of taxi services on cities, but this comes at the expense of passenger discomfort quantifiable in terms of a longer travel time. Due to computational challenges, taxi sharing has traditionally been approached on small scales, such as within airport perimeters, or with dynamical ad hoc heuristics. However, a mathematical framework for the systematic understanding of the tradeoff between collective benefits of sharing and individual passenger discomfort is lacking. Here we introduce the notion of shareability network, which allows us to model the collective benefits of sharing as a function of passenger inconvenience, and to efficiently compute optimal sharing strategies on massive datasets. We apply this framework to a dataset of millions of taxi trips taken in New York City, showing that with increasing but still relatively low passenger discomfort, cumulative trip length can be cut by 40% or more. This benefit comes with reductions in service cost, emissions, and with split fares, hinting toward a wide passenger acceptance of such a shared service. Simulation of a realistic online system demonstrates the feasibility of a shareable taxi service in New York City. Shareability as a function of trip density saturates fast, suggesting effectiveness of the taxi sharing system also in cities with much sparser taxi fleets or when willingness to share is low. PMID:25197046

  19. Quantifying the benefits of vehicle pooling with shareability networks.

    PubMed

    Santi, Paolo; Resta, Giovanni; Szell, Michael; Sobolevsky, Stanislav; Strogatz, Steven H; Ratti, Carlo

    2014-09-16

    Taxi services are a vital part of urban transportation, and a considerable contributor to traffic congestion and air pollution causing substantial adverse effects on human health. Sharing taxi trips is a possible way of reducing the negative impact of taxi services on cities, but this comes at the expense of passenger discomfort quantifiable in terms of a longer travel time. Due to computational challenges, taxi sharing has traditionally been approached on small scales, such as within airport perimeters, or with dynamical ad hoc heuristics. However, a mathematical framework for the systematic understanding of the tradeoff between collective benefits of sharing and individual passenger discomfort is lacking. Here we introduce the notion of shareability network, which allows us to model the collective benefits of sharing as a function of passenger inconvenience, and to efficiently compute optimal sharing strategies on massive datasets. We apply this framework to a dataset of millions of taxi trips taken in New York City, showing that with increasing but still relatively low passenger discomfort, cumulative trip length can be cut by 40% or more. This benefit comes with reductions in service cost, emissions, and with split fares, hinting toward a wide passenger acceptance of such a shared service. Simulation of a realistic online system demonstrates the feasibility of a shareable taxi service in New York City. Shareability as a function of trip density saturates fast, suggesting effectiveness of the taxi sharing system also in cities with much sparser taxi fleets or when willingness to share is low.

  20. Development of neuronal and sensorimotor systems in the absence of gravity: Neurobiological research on four soyuz taxi flights to the international space station

    NASA Astrophysics Data System (ADS)

    Horn, Eberhard R.; Dournon, Christian; Frippiat, Jean-Pol; Marco, Roberto; Böser, Sybille; Kirschnick, Uta

    2007-09-01

    Neurobiological experiments on 4 animal species (Xenopus laevis, Pleurodeles waltl, Drosophila melanogaster, Acheta domesticus) were performed to study effects of microgravity on development and aging of neuronal, sensory and motor systems. Animal models were selected according to their suitability to answer questions concerning μg-effects on neuroanatomy, neuronal activity, and behaviour. The studies were performed on the Soyuz Taxi flights Andromède, Cervantes, Eneide and LDM-TMA8/TMA7. Observations from these flights include: (1) In tadpoles and cricket larvae, morphological features of sensory cells and neurons are rarely affected by microgravity. (2) In crickets, in-flight fertilization was successful; after landing, flight larvae hatched earlier than ground reared siblings. (3) In crickets, proliferation of peptidergic neurons and their projection patterns within the nervous system were not affected by microgravity. (4) During aging, the impact of microgravity on peptidergic neurons of male Drosophila was limited to the size of cell body. (5) In Xenopus, neurophysiological features of the spinal motor system during fictive swimming were partially modified. (6) In Xenopus tadpoles, the vestibuloocular reflex was affected in an age-related manner. Modifications were also related to the occurrence of a tail lordosis induced by microgravity. It is concluded that adaptation to microgravity during development and aging is mainly based on physiological mechanisms within the central nervous system while structural modifications of the sensory and neuronal system contribute less.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feibel, C.E.

    This study uses multiple data collection and research methods including in depth interviews, 271 surveys of shared taxi and minibus operators, participant observation, secondary sources, and the literature on public transport from low, medium, and high-income countries. Extensive use is also made of a survey administered in Istanbul in 1976 to 1935 paratransit operators. Primary findings are that private buses are more efficient than public buses on a cost per passenger-km basis, and that private minibuses are as efficient as public buses. In terms of energy efficiency, minibuses are almost as efficient as public and private buses using actual-occupancy levels.more » Large shared taxis are twice as cost and energy efficient as cars, and small shared taxis 50% more efficient. In terms of investment cost per seat, large shared taxis have the lowest cost followed by smaller shared taxis, minibuses, and buses. Considering actual occupancy levels, minibuses are only slightly less effective in terms of congestion than buses, and large and small shared taxis are twice as effective as cars. It is also shown that minibuses and shared taxis have better service quality than buses because of higher frequencies and speeds, and because they provide a much higher probability of getting a seat than buses. Analysis of regulation and policy suggests that there are many unintended cost of public-transport regulations.« less

  2. ElectroTaxis-on-a-Chip (ETC): an integrated quantitative high-throughput screening platform for electrical field-directed cell migration.

    PubMed

    Zhao, Siwei; Zhu, Kan; Zhang, Yan; Zhu, Zijie; Xu, Zhengping; Zhao, Min; Pan, Tingrui

    2014-11-21

    Both endogenous and externally applied electrical stimulation can affect a wide range of cellular functions, including growth, migration, differentiation and division. Among those effects, the electrical field (EF)-directed cell migration, also known as electrotaxis, has received broad attention because it holds great potential in facilitating clinical wound healing. Electrotaxis experiment is conventionally conducted in centimetre-sized flow chambers built in Petri dishes. Despite the recent efforts to adapt microfluidics for electrotaxis studies, the current electrotaxis experimental setup is still cumbersome due to the needs of an external power supply and EF controlling/monitoring systems. There is also a lack of parallel experimental systems for high-throughput electrotaxis studies. In this paper, we present a first independently operable microfluidic platform for high-throughput electrotaxis studies, integrating all functional components for cell migration under EF stimulation (except microscopy) on a compact footprint (the same as a credit card), referred to as ElectroTaxis-on-a-Chip (ETC). Inspired by the R-2R resistor ladder topology in digital signal processing, we develop a systematic approach to design an infinitely expandable microfluidic generator of EF gradients for high-throughput and quantitative studies of EF-directed cell migration. Furthermore, a vacuum-assisted assembly method is utilized to allow direct and reversible attachment of our device to existing cell culture media on biological surfaces, which separates the cell culture and device preparation/fabrication steps. We have demonstrated that our ETC platform is capable of screening human cornea epithelial cell migration under the stimulation of an EF gradient spanning over three orders of magnitude. The screening results lead to the identification of the EF-sensitive range of that cell type, which can provide valuable guidance to the clinical application of EF-facilitated wound healing.

  3. NASA's SOFIA 747SP bearing a German-built 2.5-meter infrared telescope in its rear fuselage taxis up to NASA Dryden's ramp after a ferry flight from Waco, TX

    NASA Image and Video Library

    2007-05-31

    NASA's SOFIA 747SP bearing a German-built 2.5-meter infrared telescope in its rear fuselage taxis up to NASA Dryden's ramp after a ferry flight from Waco, Texas. NASA's Stratospheric Observatory for Infrared Astronomy, or SOFIA, arrived at NASA's Dryden Flight Research Center at Edwards Air Force Base, Calif. on May 31, 2007. The heavily modified Boeing 747SP was ferried to Dryden from Waco, Texas, where L-3 Communications Integrated Systems installed a German-built 2.5-meter infrared telescope and made other major modifications over the past several years. SOFIA is scheduled to undergo installation and integration of mission systems and a multi-phase flight test program at Dryden over the next three years that is expected to lead to a full operational capability to conduct astronomy missions in about 2010. During its expected 20-year lifetime, SOFIA will be capable of "Great Observatory" class astronomical science, providing astronomers with access to the visible, infrared and sub-millimeter spectrum with optimized performance in the mid-infrared to sub-millimeter range.

  4. Revealing Spatial Variation and Correlation of Urban Travels from Big Trajectory Data

    NASA Astrophysics Data System (ADS)

    Li, X.; Tu, W.; Shen, S.; Yue, Y.; Luo, N.; Li, Q.

    2017-09-01

    With the development of information and communication technology, spatial-temporal data that contain rich human mobility information are growing rapidly. However, the consistency of multi-mode human travel behind multi-source spatial-temporal data is not clear. To this aim, we utilized a week of taxies' and buses' GPS trajectory data and smart card data in Shenzhen, China to extract city-wide travel information of taxi, bus and metro and tested the correlation of multi-mode travel characteristics. Both the global correlation and local correlation of typical travel indicator were examined. The results show that: (1) Significant differences exist in of urban multi-mode travels. The correlation between bus travels and taxi travels, metro travel and taxi travels are globally low but locally high. (2) There are spatial differences of the correlation relationship between bus, metro and taxi travel. These findings help us understanding urban travels deeply therefore facilitate both the transport policy making and human-space interaction research.

  5. Structure Inference from Mobility Encounters

    DTIC Science & Technology

    2013-10-20

    world dataset, which contains 230K trajectories of taxi cabs in Beijing . Our algorithm extracts a pathlet dictionary containing around 130K...data set, frequently used pathlets in the dictionary represent driving segments chosen by many taxi cab drivers in Beijing , reflecting the joint wisdom...limitations on storage and communication bandwidth. For instance, 50% of the Beijing Taxi Trajectories we employed in this study have at most one

  6. NextGen Flight Deck Surface Trajectory-Based Operations (STBO): Contingency Holds

    NASA Technical Reports Server (NTRS)

    Bakowski, Deborah Lee; Hooey, Becky Lee; Foyle, David C.; Wolter, Cynthia A.; Cheng, Lara W. S.

    2013-01-01

    The purpose of this pilot-in-the-loop taxi simulation was to investigate a NextGen Surface Trajectory-Based Operations (STBO) concept called "contingency holds." The contingency-hold concept parses a taxi route into segments, allowing an air traffic control (ATC) surface traffic management (STM) system to hold an aircraft when necessary for safety. Under nominal conditions, if the intersection or active runway crossing is clear, the hold is removed, allowing the aircraft to continue taxiing without slowing, thus improving taxi efficiency, while minimizing the excessive brake use, fuel burn, and emissions associated with stop-and-go taxi. However, when a potential traffic conflict exists, the hold remains in place as a fail-safe mechanism. In this departure operations simulation, the taxi clearance included a required time of arrival (RTA) to a specified intersection. The flight deck was equipped with speed-guidance avionics to aid the pilot in safely meeting the RTA. On two trials, the contingency hold was not released, and pilots were required to stop. On two trials the contingency hold was released 15 sec prior to the RTA, and on two trials the contingency hold was released 30 sec prior to the RTA. When the hold remained in place, all pilots complied with the hold. Results also showed that when the hold was released at 15-sec or 30-sec prior to the RTA, the 30-sec release allowed pilots to maintain nominal taxi speed, thus supporting continuous traffic flow; whereas, the 15-sec release did not. The contingency-hold concept, with at least a 30-sec release, allows pilots to improve taxiing efficiency by reducing braking, slowing, and stopping, but still maintains safety in that no pilots "busted" the clearance holds. Overall, the evidence suggests that the contingency-hold concept is a viable concept for optimizing efficiency while maintaining safety.

  7. 14 CFR 294.40 - Aircraft accident liability insurance requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Insurance Requirements § 294.40 Aircraft accident liability insurance requirements. No Canadian charter air taxi operator shall...

  8. 14 CFR 294.40 - Aircraft accident liability insurance requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Insurance Requirements § 294.40 Aircraft accident liability insurance requirements. No Canadian charter air taxi operator shall...

  9. Reducing air pollutant emissions at airports by controlling aircraft ground operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gelinas, C.G.; Fan, H.S.L.

    1979-02-01

    Average-day carbon monoxide, total hydrocarbon, and NO/sub x/ aircraft emissions and fuel use estimates (apportioned to takeoff, taxi, idle, and landing) for departure and arrival at Los Angeles and San Francisco International Airports were compared with emissions level and fuel use estimates for four emission reduction strategies (tow aircraft between runways and gates, shutdown one engine during taxiing, control departure time, and assign runways to minimize taxiing distance). The best strategy, the shutdown of one engine while taxiing, produces substantial emission reductions, cost benefits owing to fuel savings, and no apparent safety problems; aircraft towing reduced emissions significantly, but introducedmore » a number of safety problems.« less

  10. Effects of congestion on drivers' speed choice: Assessing the mediating role of state aggressiveness based on taxi floating car data.

    PubMed

    Huang, Yizhe; Sun, Daniel Jian; Zhang, Li-Hui

    2018-08-01

    Inappropriate cruising speed, such as speeding, is one of the major contributors to the road safety, which increases both the quantitative number and severity of traffic accidents. Previous studies have indicated that traffic congestion is one of the primary causes of drivers' frustration and aggression, which may lead to inappropriate speed choice. In this study, the large taxi floating car data (FCD) was used to empirically evaluate how traffic congestion-related negative moods, defined as state aggressiveness, affected drivers' speed choice. The indirect effect of traffic delay on the cruising speed adjustment through the state aggressiveness was assessed through the mediation analysis. Furthermore, the moderated mediation analysis was performed to explore the effect of driver type, value of time, and working duration on the mediation role of state aggressiveness. The results proved that the state aggressiveness was the mediator of the relationship between travel delays and driving speed adjustment, and the mediation role was different across various driver types. As compared to the aggressive drivers, the normal drivers and the steady drivers tended to behave more aggressively after experiencing non-recurrent congestion during the early stage of the trips. When the value of time was high, steady drivers were more likely to adjust their speed choice although the effect was not statistically significant for other driver types. The validation results indicated that the speed model incorporating state aggressiveness could better predict the travel time than the traditional speed model that only considering the specific expected speed distribution. The prediction results for the manifest indicators of state aggressiveness, such as the maximum speed and the speed deviation, also demonstrated a reasonable reflection of the field data. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. 14 CFR 294.21 - Procedure on receipt of registration form.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Registration for Exemption... person objecting to the registration of a Canadian charter air taxi operator shall file an objection with...

  12. 14 CFR 294.21 - Procedure on receipt of registration form.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Registration for Exemption... person objecting to the registration of a Canadian charter air taxi operator shall file an objection with...

  13. 14 CFR 298.37 - Prohibition of services not covered by insurance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS... insurance. An air taxi operator or commuter air carrier shall not operate in air transportation or provide...

  14. 14 CFR 298.31 - Scope of service and equipment authorized.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS... transportation, and the exemption provided by this part to air taxi operators and commuter air carriers that...

  15. 14 CFR 298.37 - Prohibition of services not covered by insurance.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS... insurance. An air taxi operator or commuter air carrier shall not operate in air transportation or provide...

  16. 14 CFR 298.31 - Scope of service and equipment authorized.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS... transportation, and the exemption provided by this part to air taxi operators and commuter air carriers that...

  17. 14 CFR 211.2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... permit. (b) Canadian charter air taxi operators, foreign indirect air carriers of property, and foreign... taxi operators shall register under part 294 of this chapter, foreign indirect air carriers of property...

  18. 14 CFR 294.10 - Exemption authority.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Exemption § 294.10 Exemption authority. Canadian charter air taxi operators registered under this part are exempt from the following provisions of the Statute to...

  19. 14 CFR 211.2 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... permit. (b) Canadian charter air taxi operators, foreign indirect air carriers of property, and foreign... taxi operators shall register under part 294 of this chapter, foreign indirect air carriers of property...

  20. 14 CFR 298.33 - Security requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions..., an air taxi operator or a commuter air carrier is required to adhere to all security requirements...

  1. 14 CFR 294.10 - Exemption authority.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Exemption § 294.10 Exemption authority. Canadian charter air taxi operators registered under this part are exempt from the following provisions of the Statute to...

  2. 14 CFR 298.22 - Processing by the Department.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.22 Processing by the Department. After examination of the OST Form...

  3. 14 CFR 298.35 - Limitations on carriage of mail.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on Exemptions and Operations § 298.35 Limitations on carriage of mail. An air taxi operator or...

  4. 14 CFR 298.22 - Processing by the Department.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Registration for Exemption by Air Taxi Operators § 298.22 Processing by the Department. After examination of the OST Form...

  5. 14 CFR 298.36 - Limitations on use of business name.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on Exemptions and Operations § 298.36 Limitations on use of business name. (a) An air taxi...

  6. 14 CFR 93.153 - Communications.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... operate an aircraft within the airspace specified in § 93.151, or taxi onto the runway at Ketchikan..., or taxi onto the runway at Ketchikan International Airport, unless that person continuously monitors...

  7. 14 CFR 298.35 - Limitations on carriage of mail.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on Exemptions and Operations § 298.35 Limitations on carriage of mail. An air taxi operator or...

  8. 14 CFR 298.36 - Limitations on use of business name.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on Exemptions and Operations § 298.36 Limitations on use of business name. (a) An air taxi...

  9. Performance Evaluation of the Approaches and Algorithms Using Hamburg Airport Operations

    NASA Technical Reports Server (NTRS)

    Zhu, Zhifan; Okuniek, Nikolai; Gerdes, Ingrid; Schier, Sebastian; Lee, Hanbong; Jung, Yoon

    2016-01-01

    The German Aerospace Center (DLR) and the National Aeronautics and Space Administration (NASA) have been independently developing and testing their own concepts and tools for airport surface traffic management. Although these concepts and tools have been tested individually for European and US airports, they have never been compared or analyzed side-by-side. This paper presents the collaborative research devoted to the evaluation and analysis of two different surface management concepts. Hamburg Airport was used as a common test bed airport for the study. First, two independent simulations using the same traffic scenario were conducted; one by the DLR team using the Controller Assistance for Departure Optimization (CADEO) and the Taxi Routing for Aircraft: Creation and Controlling (TRACC) in a real-time simulation environment, and one by the NASA team based on the Spot and Runway Departure Advisor (SARDA) in a fast-time simulation environment. A set of common performance metrics was defined. The simulation results showed that both approaches produced operational benefits in efficiency, such as reducing taxi times, while maintaining runway throughput. Both approaches generated the gate pushback schedule to meet the runway schedule, such that the runway utilization was maximized. The conflict-free taxi guidance by TRACC helped avoid taxi conflicts and reduced taxiing stops, but the taxi benefit needed be assessed together with runway throughput to analyze the overall performance objective.

  10. Performance Evaluation of the Approaches and Algorithms for Hamburg Airport Operations

    NASA Technical Reports Server (NTRS)

    Zhu, Zhifan; Okuniek, Nikolai; Gerdes, Ingrid; Schier, Sebastian; Lee, Hanbong; Jung, Yoon

    2016-01-01

    The German Aerospace Center (DLR) and the National Aeronautics and Space Administration (NASA) have been independently developing and testing their own concepts and tools for airport surface traffic management. Although these concepts and tools have been tested individually for European and US airports, they have never been compared or analyzed side-by-side. This paper presents the collaborative research devoted to the evaluation and analysis of two different surface management concepts. Hamburg Airport was used as a common test bed airport for the study. First, two independent simulations using the same traffic scenario were conducted: one by the DLR team using the Controller Assistance for Departure Optimization (CADEO) and the Taxi Routing for Aircraft: Creation and Controlling (TRACC) in a real-time simulation environment, and one by the NASA team based on the Spot and Runway Departure Advisor (SARDA) in a fast-time simulation environment. A set of common performance metrics was defined. The simulation results showed that both approaches produced operational benefits in efficiency, such as reducing taxi times, while maintaining runway throughput. Both approaches generated the gate pushback schedule to meet the runway schedule, such that the runway utilization was maximized. The conflict-free taxi guidance by TRACC helped avoid taxi conflicts and reduced taxiing stops, but the taxi benefit needed be assessed together with runway throughput to analyze the overall performance objective.

  11. Performance Evaluation of the Approaches and Algorithms using Hamburg Airport Operations

    NASA Technical Reports Server (NTRS)

    Zhu, Zhifan; Lee, Hanbong; Jung, Yoon; Okuniek, Nikolai; Gerdes, Ingrid; Schier, Sebastian

    2016-01-01

    The German Aerospace Center (DLR) and the National Aeronautics and Space Administration (NASA) have been independently developing and testing their own concepts and tools for airport surface traffic management. Although these concepts and tools have been tested individually for European and US airports, they have never been compared or analyzed side-by-side. This paper presents the collaborative research devoted to the evaluation and analysis of two different surface management concepts. Hamburg Airport was used as a common test bed airport for the study. First, two independent simulations using the same traffic scenario were conducted: one by the DLR team using the Controller Assistance for Departure Optimization (CADEO) and the Taxi Routing for Aircraft58; Creation and Controlling (TRACC) in a real-time simulation environment, and one by the NASA team based on the Spot and Runway Departure Advisor (SARDA) in a fast-time simulation environment. A set of common performance metrics was defined. The simulation results showed that both approaches produced operational benefits in efficiency, such as reducing taxi times, while maintaining runway throughput. Both approaches generated the gate pushback schedule to meet the runway schedule, such that the runway utilization was maximized. The conflict-free taxi guidance by TRACC helped avoid taxi conflicts and reduced taxiing stops, but the taxi benefit needed be assessed together with runway throughput to analyze the overall performance objective.

  12. 14 CFR 205.2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... air carriers, including commuter air carriers and air taxi operators as defined in § 298.2 of this chapter, and foreign direct air carriers, including Canadian charter air taxi operators as defined in...

  13. 14 CFR 380.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... waybilled basis. Direct air carrier means a certificated commuter or foreign air carrier, or an air taxi operator registered under part 298 of this chapter, or a Canadian charter air taxi operator registered...

  14. 14 CFR 205.2 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... air carriers, including commuter air carriers and air taxi operators as defined in § 298.2 of this chapter, and foreign direct air carriers, including Canadian charter air taxi operators as defined in...

  15. Real-world fuel efficiency and exhaust emissions of light-duty diesel vehicles and their correlation with road conditions.

    PubMed

    Hu, Jingnan; Wu, Ye; Wang, Zhishi; Li, Zhenhua; Zhou, Yu; Wang, Haitao; Bao, Xiaofeng; Hao, Jiming

    2012-01-01

    The real-world fuel efficiency and exhaust emission profiles of CO, HC and NOx for light-duty diesel vehicles were investigated. Using a portable emissions measurement system, 16 diesel taxies were tested on different roads in Macao and the data were normalized with the vehicle specific power bin method. The 11 Toyota Corolla diesel taxies have very good fuel economy of (5.9 +/- 0.6) L/100 km, while other five diesel taxies showed relatively high values at (8.5 +/- 1.7) L/100 km due to the variation in transmission systems and emission control strategies. Compared to similar Corolla gasoline models, the diesel cars confirmed an advantage of ca. 20% higher fuel efficiency. HC and CO emissions of all the 16 taxies are quite low, with the average at (0.05 +/- 0.02) g/km and (0.38 +/- 0.15) g/km, respectively. The average NOx emission factor of the 11 Corolla taxies is (0.56 +/- 0.17) g/km, about three times higher than their gasoline counterparts. Two of the three Hyundai Sonata taxies, configured with exhaust gas recirculation (EGR) + diesel oxidation catalyst (DOC) emission control strategies, indicated significantly higher NO2 emissions and NO2/NOx ratios than other diesel taxies and consequently trigger a concern of possibly adverse impacts on ozone pollution in urban areas with this technology combination. A clear and similar pattern for fuel consumption and for each of the three gaseous pollutant emissions with various road conditions was identified. To save energy and mitigate CO2 emissions as well as other gaseous pollutant emissions in urban area, traffic planning also needs improvement.

  16. Taxifolin synergizes Andrographolide-induced cell death by attenuation of autophagy and augmentation of caspase dependent and independent cell death in HeLa cells

    PubMed Central

    Alzaharna, Mazen; Alqouqa, Iyad; Cheung, Hon-Yeung

    2017-01-01

    Andrographolide (Andro) has emerged recently as a potential and effective anticancer agent with induction of apoptosis in some cancer cell lines while induction of G2/M arrest with weak apoptosis in others. Few studies have proved that Andro is also effective in combination therapy. The flavonoid Taxifolin (Taxi) has showed anti-oxidant and antiproliferative effects against different cancer cells. Therefore, the present study investigated the cytotoxic effects of Andro alone or in combination with Taxi on HeLa cells. The combination of Andro with Taxi was synergistic at all tested concentrations and combination ratios. Andro alone induced caspase-dependent apoptosis which was enhanced by the combination with Taxi and attenuated partly by using Z-Vad-Fmk. Andro induced a protective reactive oxygen species (ROS)-dependent autophagy which was attenuated by Taxi. The activation of p53 was involved in Andro-induced autophagy where the use of Taxi or pifithrin-α (PFT-α) decreased it while the activation of JNK was involved in the cell death of HeLa cells but not in the induction of autophagy. The mitochondrial outer-membrane permeabilization (MOMP) plays an important role in Andro-induced cell death in HeLa cells. Andro alone increased the MOMP which was further increased in the case of combination. This led to the increase in AIF and cytochrome c release from mitochondria which consequently increased caspase-dependent and independent cell death. In conclusion, Andro induced a protective autophagy in HeLa cells which was reduced by Taxi and the cell death was increased by increasing the MOMP and subsequently the caspase-dependent and independent cell death. PMID:28182713

  17. 14 CFR 298.4 - Requests for statement of authority.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.4 Requests for statement of authority. In any instance where an air taxi operator or commuter air carrier is...

  18. 14 CFR 203.3 - Filing requirements for adherence to Montreal Agreement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... a party. U.S. air taxi operators registering under part 298 of this chapter and Canadian charter air taxi operators registering under part 294 of this chapter may comply with this requirement by filing...

  19. 14 CFR 298.1 - Applicability of part.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.1 Applicability of part. This part establishes classifications of air carriers known as “air taxi operators” and “commuter air...

  20. 14 CFR 298.1 - Applicability of part.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.1 Applicability of part. This part establishes classifications of air carriers known as “air taxi operators” and “commuter air...

  1. 14 CFR 203.3 - Filing requirements for adherence to Montreal Agreement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... a party. U.S. air taxi operators registering under part 298 of this chapter and Canadian charter air taxi operators registering under part 294 of this chapter may comply with this requirement by filing...

  2. 14 CFR 294.2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General § 294.2 Definitions. As used in this part: (a..., reservations, or supersessions to it. (b) Canadian charter air taxi operator means a foreign air carrier that...

  3. 14 CFR 298.4 - Requests for statement of authority.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.4 Requests for statement of authority. In any instance where an air taxi operator or commuter air carrier is...

  4. 14 CFR 253.8 - Qualifications to notice requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... without penalty. (b) An air taxi operator (including a commuter air carrier) not operating under subpart I..., such an air taxi operator may not claim the benefit as against the passenger of, and the passenger...

  5. 14 CFR 253.8 - Qualifications to notice requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... without penalty. (b) An air taxi operator (including a commuter air carrier) not operating under subpart I..., such an air taxi operator may not claim the benefit as against the passenger of, and the passenger...

  6. 14 CFR 380.11 - Payment to direct air carrier(s).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... carrier(s). Except for air taxi operators and commuter air carriers (which are governed by 14 CFR 298.38) and Canadian charter air taxi operators (which are governed by 14 CFR 294.32), the direct air carrier...

  7. 14 CFR 380.11 - Payment to direct air carrier(s).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... carrier(s). Except for air taxi operators and commuter air carriers (which are governed by 14 CFR 298.38) and Canadian charter air taxi operators (which are governed by 14 CFR 294.32), the direct air carrier...

  8. The effect of navigational expertise on wayfinding in new environments.

    PubMed

    Woollett, Katherine; Maguire, Eleanor A

    2010-12-01

    Becoming proficient at navigation in urban environments is something that we all aspire to. Here we asked whether being an expert at wayfinding in one environment has any effect on learning new spatial layouts. Licensed London taxi drivers are among the most proficient urban navigators, training for many years to find their way around a complex and irregularly-laid out city. We first tested how well they could learn the layout of an unfamiliar town compared with a group of non-taxi drivers. Second, we investigated how effectively taxi drivers could integrate a new district into their existing spatial representation of London. We found that taxi drivers were significantly better than control participants at executing routes through the new town, and representing it at a map-like survey level. However, the benefits of navigational expertise were not universal. Compared with their performance in the new town, taxi drivers were significantly poorer at learning the layout of a new area that had to be integrated with their existing knowledge of London. We consider reasons for this picture of facilitation and limitation, in particular drawing parallels with how knowledge acquisition occurs in the context of expertise in general.

  9. Engineering Safety- and Security-Related Requirements for Software-Intensive Systems

    DTIC Science & Technology

    2007-02-27

    the Zoo Loop Line to enter the inner Great Apes and Monkeys taxi station. Exiting the taxi when the doors open, they head down the elevator and...Carnegie Mellon University Example Overview Very Large New Zoo Zoo Automated Taxi System (ZATS) Example Zoo Habitat Guideway Layout ZATS Context Diagram...Firesmith, 27 February 2007 © 2007 Carnegie Mellon University Very Large New Zoo P a rk in g L o ts Z o o B a c k L o ts R e s ta u ra n ts a n d S h o

  10. Taxiway aircraft traffic analysis at George Bush Intercontinental Airport.

    DOT National Transportation Integrated Search

    2011-08-01

    Serving one of the largest metropolitan areas in the United States, the George Bush Intercontinental Airport : (IAH) is among the 10 airports with the longest average taxi-out and taxi-in times. The first part of this report : assesses the congestion...

  11. 78 FR 56707 - Proposed Data Collections Submitted for Public Comment and Recommendations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... days of this notice. Proposed Project Taxi Driver Survey on Motor Vehicle Safety and Workplace Violence (or, Taxi Driver Survey)--New--National Institute for Occupational Safety and Health (NIOSH), Centers... vehicle safety findings from this survey will be disseminated globally to municipal transportation...

  12. 14 CFR 330.43 - What classes of air carriers are eligible under the set-aside?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... are two classes of eligible air carriers: (a) You are a Class I air carrier if you are an air taxi... month of August, 2001. (b) You are a Class II air carrier if you are an air taxi, regional, commuter or...

  13. 14 CFR 330.43 - What classes of air carriers are eligible under the set-aside?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... are two classes of eligible air carriers: (a) You are a Class I air carrier if you are an air taxi... month of August, 2001. (b) You are a Class II air carrier if you are an air taxi, regional, commuter or...

  14. Air transport pilots' information priorities for surface moving maps

    DOT National Transportation Integrated Search

    2003-10-13

    The use of a surface map display for operations on or near the airport surface (taxi out, takeoff, final approach and landing, taxi in) is expected to enhance safety. There is a lack of research, however, detailing how the airport surface should be d...

  15. Flight Deck Surface Trajectory-based Operations (STBO): Results of Piloted Simulations and Implications for Concepts of Operation (ConOps)

    NASA Technical Reports Server (NTRS)

    Foyle, David C.; Hooey, Becky L.; Bakowski, Deborah L.

    2013-01-01

    The results offour piloted medium-fidelity simulations investigating flight deck surface trajectory-based operations (STBO) will be reviewed. In these flight deck STBO simulations, commercial transport pilots were given taxi clearances with time and/or speed components and required to taxi to the departing runway or an intermediate traffic intersection. Under a variety of concept of operations (ConOps) and flight deck information conditions, pilots' ability to taxi in compliance with the required time of arrival (RTA) at the designated airport location was measured. ConOps and flight deck information conditions explored included: Availability of taxi clearance speed and elapsed time information; Intermediate RTAs at intermediate time constraint points (e.g., intersection traffic flow points); STBO taxi clearances via ATC voice speed commands or datal ink; and, Availability of flight deck display algorithms to reduce STBO RTA error. Flight Deck Implications. Pilot RTA conformance for STBO clearances, in the form of ATC taxi clearances with associated speed requirements, was found to be relatively poor, unless the pilot is required to follow a precise speed and acceleration/deceleration profile. However, following such a precise speed profile results in inordinate head-down tracking of current ground speed, leading to potentially unsafe operations. Mitigating these results, and providing good taxi RTA performance without the associated safety issues, is a flight deck avionics or electronic flight bag (EFB) solution. Such a solution enables pilots to meet the taxi route RTA without moment-by-moment tracking of ground speed. An avionics or EFB "error-nulling" algorithm allows the pilot to view the STBO information when the pilot determines it is necessary and when workload alloys, thus enabling the pilot to spread his/her attention appropriately and strategically on aircraft separation airport navigation, and the many other flight deck tasks concurrently required

  16. 14 CFR 298.3 - Classification.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Classification. 298.3 Section 298.3... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.3 Classification. (a) There is hereby established a classification of air carriers, designated as “air taxi operators,” which...

  17. 14 CFR 298.3 - Classification.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Classification. 298.3 Section 298.3... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.3 Classification. (a) There is hereby established a classification of air carriers, designated as “air taxi operators,” which...

  18. 14 CFR 298.3 - Classification.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Classification. 298.3 Section 298.3... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.3 Classification. (a) There is hereby established a classification of air carriers, designated as “air taxi operators,” which...

  19. 14 CFR 298.3 - Classification.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Classification. 298.3 Section 298.3... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.3 Classification. (a) There is hereby established a classification of air carriers, designated as “air taxi operators,” which...

  20. 14 CFR 298.3 - Classification.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Classification. 298.3 Section 298.3... REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS General § 298.3 Classification. (a) There is hereby established a classification of air carriers, designated as “air taxi operators,” which...

  1. Characteristics of carbonyl compounds in public vehicles of Beijing city: Concentrations, sources, and personal exposures

    NASA Astrophysics Data System (ADS)

    Pang, Xiaobing; Mu, Yujing

    The characteristics of carbonyl compounds (carbonyls) including concentrations, major sources, and personal exposure were investigated for 29 vehicles including taxi, bus and subway in Beijing. It was found that the taxis (Xiali, TA) and buses (Huanghe, BA) fueled by gasoline with longer service years had the higher indoor carbonyl levels (178±42.7 and 188±31.6 μg m -3) while subways energized by electricity without exhaust and the jingwa buses (BB) driven in the suburb had the lower levels with total concentrations of 98.5±26.3 and 92.1±20.3 μg m -3, respectively. Outdoor carbonyls of taxi cars and buses were nearly at the same level with their total concentrations varying from 80 to 110 μg m -3. The level of outdoor subways carbonyls was equal with the ambient air levels. Exhaust leakage, indoor material emissions, photochemical formation, and infiltration of outdoor air were considered to be the major sources to in-vehicle carbonyls. Personal exposures and cancer risk to formaldehyde and acetaldehyde were calculated for professional bus and taxi drivers, respectively. Taxi drivers had the highest cancer risk with personal exposure to formaldehyde and acetaldehyde of 212 and 243 μg day -1, respectively. The public concern should pay considerable attention to professional drivers' health.

  2. DataComm in Flight Deck Surface Trajectory-Based Operations

    NASA Technical Reports Server (NTRS)

    Bakowski, Deborah L.; Foyle, David C.; Hooey, Becky L.; Meyer, Glenn R.; Wolter, Cynthia A.

    2012-01-01

    The purpose of this pilot-in-the-loop aircraft taxi simulation was to evaluate a NextGen concept for surface trajectory-based operations (STBO) in which air traffic control (ATC) issued taxi clearances with a required time of arrival (RTA) by Data Communications (DataComm). Flight deck avionics, driven by an error-nulling algorithm, displayed the speed needed to meet the RTA. To ensure robustness of the algorithm, the ability of 10 two-pilot crews to meet the RTA was tested in nine experimental trials representing a range of realistic conditions including a taxi route change, an RTA change, a departure clearance change, and a crossing traffic hold scenario. In some trials, these DataComm taxi clearances or clearance modifications were accompanied by 'preview' information, in which the airport map display showed a preview of the proposed route changes, including the necessary speed to meet the RTA. Overall, the results of this study show that with the aid of the RTA speed algorithm, pilots were able to meet their RTAs with very little time error in all of the robustness-testing scenarios. Results indicated that when taxi clearance changes were issued by DataComm only, pilots required longer notification distances than with voice communication. However, when the DataComm was accompanied by graphical preview, the notification distance required by pilots was equivalent to that for voice.

  3. DataComm in Flight Deck Surface Trajectory-Based Operations. Chapter 20

    NASA Technical Reports Server (NTRS)

    Bakowski, Deborah L.; Foyle, David C.; Hooey, Becky L.; Meyer, Glenn R.; Wolter, Cynthia A.

    2012-01-01

    The purpose of this pilot-in-the-loop aircraft taxi simulation was to evaluate a NextGen concept for surface trajectory-based operations (STBO) in which air traffic control (ATC) issued taxi clearances with a required time of arrival (RTA) by Data Communications (DataComm). Flight deck avionics, driven by an error-nulling algorithm, displayed the speed needed to meet the RTA. To ensure robustness of the algorithm, the ability of 10 two-pilot crews to meet the RTA was tested in nine experimental trials representing a range of realistic conditions including a taxi route change, an RTA change, a departure clearance change, and a crossing traffic hold scenario. In some trials, these DataComm taxi clearances or clearance modifications were accompanied by preview information, in which the airport map display showed a preview of the proposed route changes, including the necessary speed to meet the RTA. Overall, the results of this study show that with the aid of the RTA speed algorithm, pilots were able to meet their RTAs with very little time error in all of the robustness-testing scenarios. Results indicated that when taxi clearance changes were issued by DataComm only, pilots required longer notification distances than with voice communication. However, when the DataComm was accompanied by graphical preview, the notification distance required by pilots was equivalent to that for voice.

  4. X-36 Tailless Fighter Agility Research Aircraft on lakebed during high-speed taxi tests

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA/McDonnell Douglas Corporation (MDC) X-36 Tailless Fighter Agility Research Aircraft undergoes high-speed taxi tests on Rogers Dry Lake at NASA Dryden Flight Research Center, Edwards, California, on October 17, 1996. The aircraft was tested at speeds up to 85 knots. Normal takeoff speed would be 110 knots. The NASA/Boeing X-36 Tailless Fighter Agility Research Aircraft program successfully demonstrated the tailless fighter design using advanced technologies to improve the maneuverability and survivability of possible future fighter aircraft. The program met or exceeded all project goals. For 31 flights during 1997 at the Dryden Flight Research Center, Edwards, California, the project team examined the aircraft's agility at low speed / high angles of attack and at high speed / low angles of attack. The aircraft's speed envelope reached up to 206 knots (234 mph). This aircraft was very stable and maneuverable. It handled very well. The X-36 vehicle was designed to fly without the traditional tail surfaces common on most aircraft. Instead, a canard forward of the wing was used as well as split ailerons and an advanced thrust-vectoring nozzle for directional control. The X-36 was unstable in both pitch and yaw axes, so an advanced, single-channel digital fly-by-wire control system (developed with some commercially available components) was put in place to stabilize the aircraft. Using a video camera mounted in the nose of the aircraft and an onboard microphone, the X-36 was remotely controlled by a pilot in a ground station virtual cockpit. A standard fighter-type head-up display (HUD) and a moving-map representation of the vehicle's position within the range in which it flew provided excellent situational awareness for the pilot. This pilot-in-the-loop approach eliminated the need for expensive and complex autonomous flight control systems and the risks associated with their inability to deal with unknown or unforeseen phenomena in flight. Fully fueled the X

  5. On the Functional Neuroanatomy of Visual Word Processing: Effects of Case and Letter Deviance

    ERIC Educational Resources Information Center

    Kronbichler, Martin; Klackl, Johannes; Richlan, Fabio; Schurz, Matthias; Staffen, Wolfgang; Ladurner, Gunther; Wimmer, Heinz

    2009-01-01

    This functional magnetic resonance imaging study contrasted case-deviant and letter-deviant forms with familiar forms of the same phonological words (e.g., "TaXi" and "Taksi" vs. "Taxi") and found that both types of deviance led to increased activation in a left occipito-temporal region, corresponding to the visual word form area (VWFA). The…

  6. Flight Deck Surface Trajectory-Based Operations

    NASA Technical Reports Server (NTRS)

    Foyle, David C.; Hooey, Becky L.; Bakowski, Deborah L.

    2017-01-01

    Surface Trajectory-Based Operations (STBO) is a future concept for surface operations where time requirements are incorporated into taxi operations to support surface planning and coordination. Pilot-in-the-loop flight deck simulations have been conducted to study flight deck displays algorithms to aid pilots in complying with the time requirements of time-based taxi operations (i.e., at discrete locations in 3 12 D operations or at all points along the route in 4DT operations). The results of these studies (conformance, time-of-arrival error, eye-tracking data, and safety ratings) are presented. Flight deck simulation work done in collaboration with DLR is described. Flight deck research issues in future auto-taxi operations are also introduced.

  7. Last Call: decreasing drunk driving among 21-34-year-old bar patrons.

    PubMed

    Rivara, Frederick P; Boisvert, Deanne; Relyea-Chew, Annemarie; Gomez, Tony

    2012-01-01

    Any effort to decrease the toll of drunk driving must include efforts directed at people who drink in bars, particularly young adults who use motor vehicles after drinking. We designed a multifaceted social marketing campaign, Last Call, to increase the use of designated drivers and safe rides homes among 21-34-year olds. There were three components to the intervention: (1) use of taxi stands to promote taxi use; (2) point-of-sale information to patrons at partner bars and (3) a mass media campaign to support the designated driver/safe ride home message. Among the heaviest drinkers, the programme significantly increased the use of designated drivers and increased the use of taxis by 63%.

  8. Haitian Tap-Taps

    ERIC Educational Resources Information Center

    Sterling, Joan

    2011-01-01

    In the small island country of Haiti, colorful taxis transport the natives to the market. Although the taxis may be crowded with people, goods, and even livestock, it is considered a luxury to ride rather than go on foot. The children's picture book, "Tap-Tap," is a wonderful introduction to the culture of this land. The name…

  9. Remediation of ground water containing volatile organic compounds and tritium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shukla, S.N.; Folsom, E.N.

    1994-03-01

    The Trailer 5475 (T-5475) East Taxi Strip Area at Lawrence Livermore National Laboratory (LLNL), Livermore, California was used as a taxi strip by the US Navy to taxi airplanes to the runway from 1942 to 1947. Solvents were used in some unpaved areas adjacent to the East Taxi Strip for cleaning airplanes. From 1953 through 1976, the area was used to store and treat liquid waste. From 1962 to 1976 ponds were constructed and used for evaporation of liquid waste. As a result, the ground water in this area contains volatile organic compounds (VOCs) and tritium. The ground water inmore » this area is also known to contain hexavalent chromium that is probably naturally occurring. Therefore, LLNL has proposed ``pump-and-treat`` technology above grade in a completely closed loop system. The facility will be designed to remove the VOCs and hexavalent chromium, if any, from the ground water, and the treated ground water containing tritium will be reinjected where it will decay naturally in the subsurface. Ground water containing tritium will be reinjected into areas with equal or higher tritium concentrations to comply with California regulations.« less

  10. The perils of public transport.

    PubMed

    Atenstaedt, R L

    2007-01-01

    Section 33 of The Public Health (Control of Disease) Act 1984 makes it an offence for a person in England and Wales who is suffering from a notifiable disease, e.g. cholera, to use any bus, tram or train; or use a taxi without notifying the driver or owner of the vehicle, or their carer to allow them to do so. Section 34 of the same act prohibits the owner, driver or conductor of a bus, train or tram from carrying a person who he knows is suffering from one of these diseases However, a taxi can carry an affected person, provided this individual pays a sum in addition to the fare to cover the costs of disinfection. Assuming that the owner or driver did not know that a passenger was suffering from one of these diseases, he must inform the local authority, which is required to disinfect the taxi for free. A literature review using PubMed did not reveal any evidence that buses, trains, trams or taxis provide a significant vehicle for transmission of notifiable diseases. Is it therefore about time that a non-evidence-based and little-used law is removed from the British statute books?

  11. Fuel Reduction for the Mobility Air Forces

    DTIC Science & Technology

    2015-01-01

    turbofan engines is sufficient to move an aircraft at taxi speed on the ground. Commercial carriers regularly use one engine when taxiing.12 For...Similarly, some, but by no means all, of the ground operations fuel use can be eliminated: Turbofan engines require a warm- up and cool-down period...25 Pratt & Whitney, Operating Instructions for the PW4000 Series Commercial Turbofan Engines, online, undated. THEORETICAL  LIMIT  OF

  12. Décision d'amputation dans la prise en charge initiale d'une luxation ouverte grave de la cheville à propos d'un cas observé à l'Hôpital Laquintinie de Douala suite à un accident par moto-taxi

    PubMed Central

    Tsatedem, Faustin Atemkeng; Tsiagadigui, Jean Gustave; Ndando, Richard Polle; Arabo, Mohamadou Saidou; Bayiha, Alphonse; Kenfack, Bruno

    2012-01-01

    La décision d'amputation pour traumatisme grave de membre n'est pas toujours facile à prendre. Les auteurs rapportent le cas d'un traumatisme ouvert de la cheville gauche avec luxation tibiotalienne complète, référé pour amputation. Il s'agit d'une passagère d'une moto-taxi percutée par une voiture. A l'admission, le pouls tibial postérieur était présent et le score dit MESS (Mangled Extremity Severity Score) côté à 5, ce qui a permis et d'éviter l'amputation. Après débridement et réduction, une broche transplantaire a permis d'immobiliser la cheville et de faire les pansements. L'amputation a été évitée. La cicatrisation dirigée de la peau a été suivie par la kinésithérapie. La mobilité de la cheville autorise une marche avec cannes au quatrième mois post-opératoire. Les auteurs recommandent l'utilisation du MESS dans la décision d'amputation après traumatisme grave de membre. PMID:23396997

  13. Modeling the role of public transportation in sustaining tuberculosis transmission in South Africa.

    PubMed

    Andrews, Jason R; Morrow, Carl; Wood, Robin

    2013-03-15

    Current tuberculosis notification rates in South Africa are among the highest ever recorded. Although the human immunodeficiency virus epidemic has been a critical factor, the density of respiratory contacts in high-risk environments may be an important and underappreciated driver. Using a modified Wells-Riley model for airborne disease transmission, we estimated the risk of tuberculosis transmission on 3 modes of public transit (minibus taxis, buses, and trains) in Cape Town, South Africa, using exhaled carbon dioxide as a natural tracer gas to evaluate air exchange. Carbon dioxide measurements were performed between October and December of 2011. Environmental risk, reflected in the rebreathed fraction of air, was highest in minibus taxis and lowest in trains; however, the average number of passengers sharing an indoor space was highest in trains and lowest in minibus taxis. Among daily commuters, the annual risk of tuberculosis infection was projected to be 3.5%-5.0% and was highest among minibus taxi commuters. Assuming a duration of infectiousness of 1 year, the basic reproductive number attributable to transportation was more than 1 in all 3 modes of transportation. Given its poor ventilation and high respiratory contact rates, public transportation may play a critical role in sustaining tuberculosis transmission in South African cities.

  14. Benefit Opportunities for Integrated Surface and Airspace Departure Scheduling: A Study of Operations at Charlotte-Douglas International Airport

    NASA Technical Reports Server (NTRS)

    Coppenbarger, Rich; Jung, Yoon; Kozon, Tom; Farrahi, Amir; Malik, Wakar; Lee, Hanbong; Chevalley, Eric; Kistler, Matt

    2016-01-01

    NASA is collaborating with the FAA and aviation industry to develop and demonstrate new capabilities that integrate arrival, departure, and surface air-traffic operations. The concept relies on trajectory-based departure scheduling and collaborative decision making to reduce delays and uncertainties in taxi and climb operations. The paper describes the concept and benefit mechanisms aimed at improving flight efficiency and predictability while maintaining or improving operational throughput. The potential impact of the technology is studied and discussed through a quantitative analysis of relevant shortfalls at the site identified for initial deployment and demonstration in 2017: Charlotte-Douglas International Airport. Results from trajectory analysis indicate substantial opportunity to reduce taxi delays for both departures and arrivals by metering departures at the gate in a manner that maximizes throughput while adhering to takeoff restrictions due mostly to airspace constraints. Substantial taxi-out delay reduction is shown for flights subject to departure restrictions stemming from traffic flow management initiatives. Opportunities to improve the predictability of taxi, takeoff, and climb operations are examined and their potential impact on airline scheduling decisions and air-traffic forecasting is discussed. In addition, the potential to improve throughput with departure scheduling that maximizes use of available runway and airspace capacity is analyzed.

  15. Modeling the Role of Public Transportation in Sustaining Tuberculosis Transmission in South Africa

    PubMed Central

    Andrews, Jason R.; Morrow, Carl; Wood, Robin

    2013-01-01

    Current tuberculosis notification rates in South Africa are among the highest ever recorded. Although the human immunodeficiency virus epidemic has been a critical factor, the density of respiratory contacts in high-risk environments may be an important and underappreciated driver. Using a modified Wells-Riley model for airborne disease transmission, we estimated the risk of tuberculosis transmission on 3 modes of public transit (minibus taxis, buses, and trains) in Cape Town, South Africa, using exhaled carbon dioxide as a natural tracer gas to evaluate air exchange. Carbon dioxide measurements were performed between October and December of 2011. Environmental risk, reflected in the rebreathed fraction of air, was highest in minibus taxis and lowest in trains; however, the average number of passengers sharing an indoor space was highest in trains and lowest in minibus taxis. Among daily commuters, the annual risk of tuberculosis infection was projected to be 3.5%–5.0% and was highest among minibus taxi commuters. Assuming a duration of infectiousness of 1 year, the basic reproductive number attributable to transportation was more than 1 in all 3 modes of transportation. Given its poor ventilation and high respiratory contact rates, public transportation may play a critical role in sustaining tuberculosis transmission in South African cities. PMID:23423215

  16. Integrated Display System for Low Visibility Landing and Surface Operations

    NASA Technical Reports Server (NTRS)

    Beskenis, Sharon Otero; Green, David F., Jr.; Hyer, Paul V.; Johnson, Edward J., Jr.

    1998-01-01

    This report summarizes the software products and system architectures developed by Lockheed Martin in support of the Low Visibility Landing and Surface Operations (LVLASO) program at NASA Langley Research Center. It presents an overview of the technical aspects, capabilities, and system integration issues associated with an integrated display system (IDS) that collects, processes and presents information to an aircraft flight crew during all phases of landing, roll-out, turn-off, inbound taxi, outbound taxi and takeoff. Communications hardware, drivers, and software provide continuous real-time data at varying rates and from many different sources to the display programs for presentation on a head-down display (HDD) and/or a head-up display (HUD). An electronic moving map of the airport surface is implemented on the HDD which includes the taxi route assigned by air traffic control, a text messaging system, and surface traffic and runway status information. Typical HUD symbology for navigation and control of the aircraft is augmented to provide aircraft deceleration guidance after touchdown to a pilot selected exit and taxi guidance along the route assigned by ATC. HUD displays include scene-linked symbolic runways, runway exits and taxiways that are conformal with the actual locations on the airport surface. Display formats, system architectures, and the various IDS programs are discussed.

  17. Surface Effect Takeoff and Landing System (SETOLS)

    DTIC Science & Technology

    1974-04-01

    State-of-the-Art 33 4. Program Tranisfer ~34 5. Future Research 34 6. Current Organizational Contacts and Identification 36 I REFE~RENCES 37 DEFENSE...ability to taxi over water, mud, low tree stumps, and empty and water-filled ditches. The flight tests indicated no significant changes in the...flight Lested from hard--surface runways, turf, water, snow, and fine sand. The aircraft also demonstrated the ability to taxi across mud, low tree

  18. Pattern of seat belt wearing in Nanjing, China

    PubMed Central

    Routley, V; Ozanne‐Smith, J; Li, D; Hu, X; Wang, P; Qin, Y

    2007-01-01

    Objective To describe the patterns of seat belt wearing in Nanjing, China for drivers, front seat passengers, and rear occupants of motor vehicles. Design Roadside observational study. Setting Four sites in central and northern Nanjing during daylight hours over 1 week in April 2005. Subjects Drivers and passengers of 17 147 cars, taxis, goods vans, and pickups, which traveled in the inside traffic lane. Main outcome measures Percentage seat belt wearing for each of seating position, age/sex, time of day, vehicle type, day of week. Results The rate of seat belt wearing was significantly higher in drivers (67.3%, 95% CI 66.6 to 68.0) than front seat passengers (18.9%, 95% CI, 18.0 to 19.8). It was negligible for second front seat passengers (2.6%, 95% CI 0.3 to 4.9) and rear seat passengers (0.5%, 95% CI 0.3 to 0.7). Belt tampering, such that protection would be reduced in the event of a crash, was observed for 18.5% of taxi drivers. Drivers were most likely to wear seat belts in cars and vans and at a city roundabout; front seat passengers were most likely to wear seat belts in non‐taxi vehicles, during the evening rush hour, if the driver was wearing a belt, and on the local north road. Drivers were least likely to wear a belt in the early morning, in pickups and taxis, on Tuesday (or the following week), and on the local north road; front seat passengers were least likely to wear a belt in taxis and if the driver was not wearing a belt. Conclusions Rates of seat belt wearing by passengers were low despite national legislation and provincial regulations coming into effect several months before the survey. Combined education and enforcement are necessary accompaniments to legislation. PMID:18056315

  19. Analysis of DFW Perimeter Taxiway Operations

    NASA Technical Reports Server (NTRS)

    Engelland, Shawn A.; Ruszkowski, Louise Morgan

    2010-01-01

    This study examines operations of the perimeter taxiway system at Dallas/Fort Worth International Airport (DFW) to characterize and understand the impact of the perimeter taxiway system and to provide operational decision makers with guidance on use of this new airport resource. DFW s perimeter taxiway entered service in December 2008 and is representative of perimeter or end-around taxiways currently in use at several other airports worldwide. This perimeter taxiway analysis is a collaborative effort between NASA and various DFW stakeholders including the FAA, air carriers and the airport operator. The initial investigation has focused on quantifying perimeter taxiway usage and assessing effects on taxi times at both the local and global levels. Local-level results show taxi times via the perimeter taxiway to be about forty-five seconds longer on average, but with significantly less variability. Global-level results show average perimeter taxiway times to be a little more than one minute longer with variability that is comparable to that for other taxi paths.

  20. Female non-smokers' environmental tobacco smoking exposure by public transportation mode.

    PubMed

    Kim, Seyoung; Park, Jin-Soo; Park, Minkyu; Kim, Yeji; Lim, Sinye; Lee, Hye-Eun

    2018-01-01

    This study aimed to analyze environmental tobacco smoking exposure in female nonsmokers by public transportation mode using representative data of Koreans. Data from the Second Korean National Environmental Health Survey (2012-2014) were analyzed. Urine cotinine was analyzed by public transport behavior, secondhand smoke exposure, socioeconomic factors, and health-related factors. Participants were 1322 adult females; those with the top 75% urine cotinine concentrations were assigned to the high exposure group. A logistic regression analysis was performed considering appropriate weights and stratification according to the sample design of the Second Korean National Environmental Health Survey. The geometric mean of urine cotinine concentrations differed according to public transportation modes: subway (1.66 μg/g creatinine) bus (1.77 μg/g creatinine), and taxi (1.94 μg/g creatinine). The odds ratio [OR] was calculated for the high exposure group. The OR of the taxi (2.39; 95% confidence interval, 1.00-5.69) was statistically significantly higher than the subway value (reference), and marginally significant after adjusted with life style, sociodemographic factors and involuntary smoking frequency (2.42, 95% confidence interval, 0.97-6.04). The odds ratio of passengers who mainly used taxis was marginally significantly higher than those of passengers who used subways and buses after adjusted with life style and sociodemographic factors. Implementation of supplementary measures and further studies on exposure to environmental tobacco smoking in taxis are warranted.

  1. Older Adults' Engagement During an Intervention Involving Off-the-Shelf Videogame.

    PubMed

    Belchior, Patrícia; Marsiske, Michael; Leite, Walter L; Yam, Anna; Thomas, Kelsey; Mann, William

    2016-06-01

    The overall goal of our current study was to examine older adults' experience of Flow (i.e., subjective engagement) during the course of a home-based cognitive training program. In this study, participants took part in a home-based training program. They were randomized to one of the two training groups. One group played an off-the-shelf videogame (i.e., Crazy Taxi), and the other group played a brain training game (i.e., Insight). Training consisted of 60 training sessions of 1 hour each, which were completed in 3 months (5 hours a week). After each training session, participants completed a Flow questionnaire to measure their engagement with the training. The analysis was performed with a linear growth curve model. The results indicate that on average, there was no change in flow for the Insight group between time points. There was no difference between the initial flow status of the Insight group and the Crazy Taxi group. However, the interaction between group membership and time was statistically significant, indicating that the participants in the Crazy Taxi group increased their scores at each week at a rate that was 0.99 larger than those in the Insight group. The analyses revealed that both groups experienced increase in Flow over the period, but only participants in the Crazy Taxi group significantly improved in Flow. This has long-term implications since we would expect participation to go beyond 12 weeks in a real-world scenario.

  2. Shuttle Endeavour Mated to 747 SCA Taxi to Runway for Delivery to Kennedy Space Center, Florida

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's 747 Shuttle Carrier Aircraft No. 911, with the space shuttle orbiter Endeavour securely mounted atop its fuselage, taxies to the runway to begin the ferry flight from Rockwell's Plant 42 at Palmdale, California, where the orbiter was built, to the Kennedy Space Center, Florida. At Kennedy, the space vehicle was processed and launched on orbital mission STS-49, which landed at NASA's Ames-Dryden Flight Research Facility (later redesignated Dryden Flight Research Center), Edwards, California, 16 May 1992. NASA 911, the second modified 747 that went into service in November 1990, has special support struts atop the fuselage and internal strengthening to accommodate the added weight of the orbiters. Space Shuttles are the main element of America's Space Transportation System and are used for space research and other space applications. The shuttles are the first vehicles capable of being launched into space and returning to Earth on a routine basis. Space Shuttles are used as orbiting laboratories in which scientists and mission specialists conduct a wide variety of scientific experiments. Crews aboard shuttles place satellites in orbit, rendezvous with satellites to carry out repair missions and return them to space, and retrieve satellites and return them to Earth for refurbishment and reuse. Space Shuttles are true aerospace vehicles. They leave Earth and its atmosphere under rocket power provided by three liquid-propellant main engines with two solid-propellant boosters attached plus an external liquid-fuel tank. After their orbital missions, they streak back through the atmosphere and land like airplanes. The returning shuttles, however, land like gliders, without power and on runways. Other rockets can place heavy payloads into orbit, but, they can only be used once. Space Shuttles are designed to be continually reused. When Space Shuttles are used to transport complete scientific laboratories into space, the laboratories remain inside the payload bay

  3. A Concept and Implementation of Optimized Operations of Airport Surface Traffic

    NASA Technical Reports Server (NTRS)

    Jung, Yoon C.; Hoang, Ty; Montoya, Justin; Gupta, Gautam; Malik, Waqar; Tobias, Leonard

    2010-01-01

    This paper presents a new concept of optimized surface operations at busy airports to improve the efficiency of taxi operations, as well as reduce environmental impacts. The suggested system architecture consists of the integration of two decoupled optimization algorithms. The Spot Release Planner provides sequence and timing advisories to tower controllers for releasing departure aircraft into the movement area to reduce taxi delay while achieving maximum throughput. The Runway Scheduler provides take-off sequence and arrival runway crossing sequence to the controllers to maximize the runway usage. The description of a prototype implementation of this integrated decision support tool for the airport control tower controllers is also provided. The prototype decision support tool was evaluated through a human-in-the-loop experiment, where both the Spot Release Planner and Runway Scheduler provided advisories to the Ground and Local Controllers. Initial results indicate the average number of stops made by each departure aircraft in the departure runway queue was reduced by more than half when the controllers were using the advisories, which resulted in reduced taxi times in the departure queue.

  4. Perseus B Taxi Tests in Preparation for a New Series of Flight Tests

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Perseus B remotely piloted aircraft taxis on the runway at Edwards Air Force Base, California, before a series of development flights at NASA's Dryden flight Research Center. The Perseus B is the latest of three versions of the Perseus design developed by Aurora Flight Sciences under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. Perseus B is a remotely piloted aircraft developed as a design-performance testbed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. Perseus is one of several flight vehicles involved in the ERAST project. A piston engine, propeller-powered aircraft, Perseus was designed and built by Aurora Flight Sciences Corporation, Manassas, Virginia. The objectives of Perseus B's ERAST flight tests have been to reach and maintain horizontal flight above altitudes of 60,000 feet and demonstrate the capability to fly missions lasting from 8 to 24 hours, depending on payload and altitude requirements. The Perseus B aircraft established an unofficial altitude record for a single-engine, propeller-driven, remotely piloted aircraft on June 27, 1998. It reached an altitude of 60,280 feet. In 1999, several modifications were made to the Perseus aircraft including engine, avionics, and flight-control-system improvements. These improvements were evaluated in a series of operational readiness and test missions at the Dryden Flight Research Center, Edwards, California. Perseus is a high-wing monoplane with a conventional tail design. Its narrow, straight, high-aspect-ratio wing is mounted atop the fuselage. The aircraft is pusher-designed with the propeller mounted in the rear. This design allows for interchangeable scientific-instrument payloads to be placed in the forward fuselage. The design also allows for unobstructed airflow to the sensors and other devices mounted in the payload compartment. The Perseus B that underwent test and development in 1999 was the third generation of the Perseus

  5. Older Adults' Engagement During an Intervention Involving Off-the-Shelf Videogame

    PubMed Central

    Marsiske, Michael; Leite, Walter L.; Yam, Anna; Thomas, Kelsey; Mann, William

    2016-01-01

    Abstract Objective: The overall goal of our current study was to examine older adults' experience of Flow (i.e., subjective engagement) during the course of a home-based cognitive training program. Materials and Methods: In this study, participants took part in a home-based training program. They were randomized to one of the two training groups. One group played an off-the-shelf videogame (i.e., Crazy Taxi), and the other group played a brain training game (i.e., Insight). Training consisted of 60 training sessions of 1 hour each, which were completed in 3 months (5 hours a week). After each training session, participants completed a Flow questionnaire to measure their engagement with the training. Results: The analysis was performed with a linear growth curve model. The results indicate that on average, there was no change in flow for the Insight group between time points. There was no difference between the initial flow status of the Insight group and the Crazy Taxi group. However, the interaction between group membership and time was statistically significant, indicating that the participants in the Crazy Taxi group increased their scores at each week at a rate that was 0.99 larger than those in the Insight group. Conclusion: The analyses revealed that both groups experienced increase in Flow over the period, but only participants in the Crazy Taxi group significantly improved in Flow. This has long-term implications since we would expect participation to go beyond 12 weeks in a real-world scenario. PMID:27310479

  6. An estimation of traffic related CO2 emissions from motor vehicles in the capital city of, Iran

    PubMed Central

    2012-01-01

    Vehicle exhaust is a major source of anthropogenic carbon dioxide (CO2) in metropolitan cities. Popular community mode (buses and taxies) and about 2.4 million private cars are the main emission sources of air pollution in Tehran. A case survey has conducted to measure CO2 in four popular vehicles, bus, taxi, private car and motorcycle, which moved in the city with respectively 7800, 82358, 560000 and 2.4 million per day in 2012. Results indicated that the contribution of CO2 emissions increased in the following order: private car, motorcycle, bus and taxi. The overall average for the contribution of CO2 emissions in the private car, motorcycle, bus, and taxi were 26372, 1648, 1433 and 374 tons per day, respectively. Our results also showed that the urban transport operation consume an estimated 178 and 4224 million liter diesel and petrol per year, respectively, that have released about 10 million tons of CO2. The average contribution of CO2 emissions of private cars in Tehran was higher (88%) than other vehicles. It was concluded that high volume of traffic, transport consumption of fossil fuels and shortage of adequate public transport system are responsible for the high CO2 level in environment in Tehran. Thus, it is to be expected that CO2 as a greenhouse gas has risen in Tehran more than ever in the following years and this would be a matter of concern for the authorities to have a comprehensive plan to mitigate this phenomena. PMID:23369252

  7. An estimation of traffic related CO2 emissions from motor vehicles in the capital city of, Iran.

    PubMed

    Kakouei, Aliakbar; Vatani, Ali; Idris, Ahmed Kamal Bin

    2012-11-28

    Vehicle exhaust is a major source of anthropogenic carbon dioxide (CO2) in metropolitan cities. Popular community mode (buses and taxies) and about 2.4 million private cars are the main emission sources of air pollution in Tehran. A case survey has conducted to measure CO2 in four popular vehicles, bus, taxi, private car and motorcycle, which moved in the city with respectively 7800, 82358, 560000 and 2.4 million per day in 2012. Results indicated that the contribution of CO2 emissions increased in the following order: private car, motorcycle, bus and taxi. The overall average for the contribution of CO2 emissions in the private car, motorcycle, bus, and taxi were 26372, 1648, 1433 and 374 tons per day, respectively. Our results also showed that the urban transport operation consume an estimated 178 and 4224 million liter diesel and petrol per year, respectively, that have released about 10 million tons of CO2. The average contribution of CO2 emissions of private cars in Tehran was higher (88%) than other vehicles. It was concluded that high volume of traffic, transport consumption of fossil fuels and shortage of adequate public transport system are responsible for the high CO2 level in environment in Tehran. Thus, it is to be expected that CO2 as a greenhouse gas has risen in Tehran more than ever in the following years and this would be a matter of concern for the authorities to have a comprehensive plan to mitigate this phenomena.

  8. Sudden illness while driving a vehicle--a retrospective analysis of commercial drivers in Japan.

    PubMed

    Hitosugi, Masahito; Gomei, Sayaka; Okubo, Takao; Tokudome, Shogo

    2012-01-01

    We performed a retrospective analysis of commercial drivers to clarify the background of incidents of sudden illness while driving. The analysis used reports submitted by employers to the Japan Ministry of Land, Infrastructure, Transport, and Tourism regarding commercial drivers who had been ordered to stop driving owing to health problems. Of 211 cases with an average work history of 15.2 years, there were 88 bus drivers, 70 taxi drivers, and 53 truck drivers, 36.0% of who had died as a result of their disease. Among taxi and truck drivers, more than 70% of incidents were due to cardiac, aortic, and cerebrovascular disease. More than 80% of these were unable to avoid traffic accidents caused by sudden illness. However, among bus drivers, cardiac, aortic, and cerebrovascular disease accounted for only 23.5% of incidents, and accidents were avoided in more than half of the cases. The duration between starting work and the incident time was significantly shorter among bus drivers [mean 3.3 hours, standard deviation (SD) 3.1] than taxi (7.7 hours, SD 5.8) and truck (7.2 hours, SD 6.3) drivers (P<0.01). The difference between the sudden illness rates of taxi and truck drivers and those of bus drivers is due to both reporting bias and differences in the awareness needed to prevent disabling events while driving. As a precaution, physicians should advise commercial drivers to stop driving as soon as they detect slight discomfort. To prevent accidents, more assertive health promotion aimed at professional drivers is needed.

  9. Reducing air pollutant emissions at airports by controlling aircraft ground operations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gelinas, C.G.; Fan, H.S.L.

    1979-02-01

    Potential reductions in air pollutant emissions were determined for four stategies to control aircraft ground operations at two case study airports, Los Angeles and San Francisco International Airports. Safety, cost, and fuel savings associated with strategy implementation were examined. Two strategies, aircraft towing and shutdown of one engine during taxi operations, provided significant emission reductions. However, there are a number of safety problems associated with aircraft towing. The shutdown of one engine while taxiing was found to be the most viable strategy because of substantial emission reductions, cost benefits resulting from fuel savings, and no apparent safety problems.

  10. Analysis and Modeling of Ground Operations at Hub Airports

    NASA Technical Reports Server (NTRS)

    Atkins, Stephen (Technical Monitor); Andersson, Kari; Carr, Francis; Feron, Eric; Hall, William D.

    2000-01-01

    Building simple and accurate models of hub airports can considerably help one understand airport dynamics, and may provide quantitative estimates of operational airport improvements. In this paper, three models are proposed to capture the dynamics of busy hub airport operations. Two simple queuing models are introduced to capture the taxi-out and taxi-in processes. An integer programming model aimed at representing airline decision-making attempts to capture the dynamics of the aircraft turnaround process. These models can be applied for predictive purposes. They may also be used to evaluate control strategies for improving overall airport efficiency.

  11. Green Taxis Act of 2011

    THOMAS, 112th Congress

    Sen. Gillibrand, Kirsten E. [D-NY

    2011-03-29

    Senate - 03/29/2011 Read twice and referred to the Committee on Commerce, Science, and Transportation. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  12. Green Taxis Act of 2009

    THOMAS, 111th Congress

    Sen. Gillibrand, Kirsten E. [D-NY

    2009-10-01

    Senate - 10/01/2009 Read twice and referred to the Committee on Commerce, Science, and Transportation. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  13. Air Taxi at Your Service

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Under an exclusive agreement with Eclipse Aviation Corporation, Williams International is manufacturing the EJ22 engine, a commercial version of the NASA/Williams FJX-2, for the Eclipse 500 aircraft. The new engine, which weighs approximately 85 pounds and delivers over 770 pounds of thrust, provides a higher thrust-to-weight ratio than any commercial turbofan ever produced. Being the smallest, quietest, and lightest commercial aircraft engine currently available, the EJ22 engine makes a whole new class of twinjet light aircraft feasible.

  14. Taxis through Computer Simulation Programs.

    ERIC Educational Resources Information Center

    Park, David

    1983-01-01

    Describes a sequence of five computer programs (listings for Apple II available from author) on tactic responses (oriented movement of a cell, cell group, or whole organism in reponse to stimuli). The simulation programs are useful in helping students examine mechanisms at work in real organisms. (JN)

  15. Flight Crew Workload, Acceptability, and Performance When Using Data Comm in a High-Density Terminal Area Simulation

    NASA Technical Reports Server (NTRS)

    Norman, R. Michael; Baxley, Brian T.; Adams, Cathy A.; Ellis, Kyle K. E.; Latorella, Kara A.; Comstock, James R., Jr.

    2013-01-01

    This document describes a collaborative FAA/NASA experiment using 22 commercial airline pilots to determine the effect of using Data Comm to issue messages during busy, terminal area operations. Four conditions were defined that span current day to future flight deck equipage: Voice communication only, Data Comm only, Data Comm with Moving Map Display, and Data Comm with Moving Map displaying taxi route. Each condition was used in an arrival and a departure scenario at Boston Logan Airport. Of particular interest was the flight crew response to D-TAXI, the use of Data Comm by Air Traffic Control (ATC) to send taxi instructions. Quantitative data was collected on subject reaction time, flight technical error, operational errors, and eye tracking information. Questionnaires collected subjective feedback on workload, situation awareness, and acceptability to the flight crew for using Data Comm in a busy terminal area. Results showed that 95% of the Data Comm messages were responded to by the flight crew within one minute and 97% of the messages within two minutes. However, post experiment debrief comments revealed almost unanimous consensus that two minutes was a reasonable expectation for crew response. Flight crews reported that Expected D-TAXI messages were useful, and employment of these messages acceptable at all altitude bands evaluated during arrival scenarios. Results also indicate that the use of Data Comm for all evaluated message types in the terminal area was acceptable during surface operations, and during arrivals at any altitude above the Final Approach Fix, in terms of response time, workload, situation awareness, and flight technical performance. The flight crew reported the use of Data Comm as implemented in this experiment as unacceptable in two instances: in clearances to cross an active runway, and D-TAXI messages between the Final Approach Fix and 80 knots during landing roll. Critical cockpit tasks and the urgency of out-the window scan made the

  16. Bacterial navigation in chemical and nonchemical environments

    NASA Astrophysics Data System (ADS)

    Hu, Bo; Tu, Yuhai

    2014-03-01

    Navigation of cells to the optimal environmental niches is critical for their survival and growth. E. coli cells, for example, can detect various chemicals and move up or down those chemical gradients (i.e., chemotaxis). Using the same signaling machinery, they can also sense other external factors such as pH and temperature and navigate from both sides toward some intermediate levels of those stimuli. This mode of precision sensing is more sophisticated than the (unidirectional) chemotaxis strategy and requires distinctive molecular mechanisms. To understand different bacterial taxis behaviors, we develop a theoretical model which incorporates microscopic signaling events in individual cells into macroscopic population dynamics. We find that the equilibrium population distribution is governed by an effective potential, the landscape of which depends on the external environment (chemical stimuli, pH, and temperature). We uncover the key conditions for various taxis behaviors and directly connects the cellular taxis performances with the underlying molecular parameters. This approach is used to examine and predict how background attractants and downstream temperature effects influence the performance and stability of thermotaxis, which can be tested in future experiments. This work is supported by the National Institutes of Health Grant GM081747.

  17. Building the Traffic, Navigation, and Situation Awareness System (T-NASA) for Surface Operations

    NASA Technical Reports Server (NTRS)

    McCann, Robert S.

    1996-01-01

    We report the results of a part-task simulation evaluating the separate and combined effects of an electronic moving map display and newly developed HUD symbology on ground taxi performance, under moderate- and low-visibility conditions. Twenty-four commercial airline pilots carried out a series of 28 gate-to-runway taxi trials at Chicago O'Hare. Half of the trials were conducted under moderate visibility (RVR 1400 ft), and half under low visibility (RVR 700 ft). In the baseline condition, where navigation support was limited to surface features and a Jeppesen paper map, navigation errors were committed on almost half of the trials. These errors were virtually abolished when the electronic moving map or the HUD symbology was available; in addition, compare, the baseline condition, both forms of navigation aid yielded an increase in forward taxi speed. The speed increase was greater for HUD than the electronic moving map, and greater under low visibility than under moderate visibility. These results suggest that combination of electronic moving map and HUD symbology has the potential to greatly increase the efficiency of ground operations, particularly under low-visibility conditions.

  18. The binomial work-health in the transit of Curitiba city.

    PubMed

    Tokars, Eunice; Moro, Antonio Renato Pereira; Cruz, Roberto Moraes

    2012-01-01

    The working activity in traffic of the big cities complex interacts with the environment is often in unsafe and unhealthy imbalance favoring the binomial work - health. The aim of this paper was to analyze the relationship between work and health of taxi drivers in Curitiba, Brazil. This cross-sectional observational study with 206 individuals used a questionnaire on the organization's profile and perception of the environment and direct observation of work. It was found that the majority are male, aged between 26 and 49 years and has a high school degree. They are sedentary, like making a journey from 8 to 12 hours. They consider a stressful profession, related low back pain and are concerned about safety and accidents. 40% are smokers and consume alcoholic drink and 65% do not have or do not use devices of comfort. Risk factors present in the daily taxi constraints cause physical, cognitive and organizational and can affect your performance. It is concluded that the taxi drivers must change the unhealthy lifestyle, requiring a more efficient management of government authorities for this work is healthy and safe for all involved.

  19. Summary of NASA landing-gear research

    NASA Technical Reports Server (NTRS)

    Fisher, B. D.; Sleeper, R. K.; Stubbs, S. M.

    1978-01-01

    This paper presents a brief summary of the airplane landing gear research underway at NASA. The technology areas include: ground handling simulator, antiskid braking systems, space shuttle nose-gear shimmy, active control landing gear, wire brush skid landing gear, air cushion landing systems, tire/surface friction characteristics, tire mechanical properties, tire-tread materials, powered wheels for taxiing, and crosswind landing gear. This paper deals mainly with the programs on tire-tread materials, powered wheel taxiing, air cushion landing systems, and crosswind landing gear research with particular emphasis on previously unreported results of recently completed flight tests. Work in the remaining areas is only mentioned.

  20. 5 CFR 532.313 - Private sector industries.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... electrical signals. 335311 Power, distribution, and specialty transformer manufacturing. 48531 Taxi service... Electronic coil, transformer, and other inductor manufacturing. 334417 Electronic connector manufacturing...

  1. A water-cannon salute from two Air Force fire trucks heralds NASA research pilot Gordon Fullerton's final mission as his NASA F/A-18 taxis beneath the spray.

    NASA Image and Video Library

    2007-12-21

    Long-time NASA Dryden research pilot and former astronaut C. Gordon Fullerton capped an almost 50-year flying career, including more than 38 years with NASA, with a final flight in a NASA F/A-18 on Dec. 21, 2007. Fullerton and Dryden research pilot Jim Smolka flew a 90-minute pilot proficiency formation aerobatics flight with another Dryden F/A-18 and a Dryden T-38 before concluding with two low-level formation flyovers of Dryden before landing. Fullerton was honored with a water-cannon spray arch provided by two fire trucks from the Edwards Air Force Base fire department as he taxied the F/A-18 up to the Dryden ramp, and was then greeted by his wife Marie and several hundred Dryden staff after his final flight. Fullerton began his flying career with the U.S. Air Force in 1958 after earning bachelor's and master's degrees in mechanical engineering from the California Institute of Technology. Initially trained as a fighter pilot, he later transitioned to multi-engine bombers and became a bomber operations test pilot after attending the Air Force Aerospace Research Pilot School at Edwards Air Force Base, Calif. He then was assigned to the flight crew for the planned Air Force Manned Orbital Laboratory in 1966. Upon cancellation of that program, the Air Force assigned Fullerton to NASA's astronaut corps in 1969. He served on the support crews for the Apollo 14, 15, 16 and 17 lunar missions, and was later assigned to one of the two flight crews that piloted the space shuttle prototype Enterprise during the Approach and Landing Test program at Dryden. He then logged some 382 hours in space when he flew on two early space shuttle missions, STS-3 on Columbia in 1982 and STS-51F on Challenger in 1985. He joined the flight crew branch at NASA Dryden after leaving the astronaut corps in 1986. During his 21 years at Dryden, Fullerton was project pilot on a number of high-profile research efforts, including the Propulsion Controlled Aircraft, the high-speed landing tests of

  2. Social marketing campaign swaps condoms for bottle tops.

    PubMed

    1993-01-01

    PSI, a non-profit organization based in the United States, uses private sector condom marketing programs to provide condoms to developing countries at low cost to help stem the spread of AIDS. PSI started promoting condoms in the CAR in November 1991. 150,000 Prudence brand condoms were sold in the 1st month. The price for a pack of 4 was far below that charged by private pharmacies. PSI turned to a collaborative venture with Societe Centrafricaine des Boissons (SCB), a local drinks manufacturer. In a joint campaign in April 1992, 4 packs of condoms were exchanged for 5 tops from SCB bottles. At markets and bars promotional items were given away during condom demonstration contests. SCB bought all the condoms from PSI and financed all the publicity. Similar promotion launched the improved Prudence Plus condom in December. Cumulative sales of Prudence and Plus condoms in the CAR now exceed 1 million. Another marketing idea was to commission a textile company called UCATEX to design a fabric based on the Prudence logo. 1600 lengths of cotton cloth were printed and sold. There was also Operation Taxi Bus. PSI's team broadcast twice on the taxi association's weekly radio show about AIDS prevention, the importance of condoms, and the Prudence brand. Then, every morning for a week, PSI promoters put stickers on as many taxis as possible. Every driver agreeing to display a sticker was entitled to receive 2 packets of Prudence for personal use. The 450 taxis with stickers now in a city of 500,000 are an effective promotion network. In order to prevent a gap in supply before PSI receives its long-term funding from a US donor, The World Health Organization recently bought 500,000 Prudence condoms for PSI to distribute.

  3. Personal exposure to black carbon during commuting in peak and off-peak hours in Shanghai.

    PubMed

    Li, Bo; Lei, Xiao-ning; Xiu, Guang-li; Gao, Chi-yuan; Gao, Shuang; Qian, Ni-sheng

    2015-08-15

    A study on a commuter's exposure to black carbon (BC) in five different traffic modes (taxi, bus, subway, cycling and walking) was conducted in Xuhui District, Shanghai. A commuter's real-time exposure concentrations were recorded by MicroAeth AE51 BC monitors, and the average BC exposure concentration and inhalation dose were analyzed. Data collected by cyclist was applied to characterize the micro-variability in relation to traffic density and street topology. The distance to the traffic and the street topology as well as the volume of heavy diesel trucks were the dominant factors influencing the BC concentrations. In this study, a high variability of BC concentrations between streets and even within streets was observed, and also between days and hour of the day. The average BC exposure concentrations were 5.59±1.02 μg/m(3), 6.58±1.78 μg/m(3), 7.28±1.87 μg/m(3), 8.62±4.13 μg/m(3) and 9.43±2.89 μg/m(3) for walking, cycling, bus, taxi and subway trips, respectively. Exposure levels of in-vehicle microenvironments were 8.66±3.66 μg/m(3), 9.39±6.98 μg/m(3) and 10.96±2.72 μg/m(3) for bus, taxi and subway, respectively. While inhalation doses were 0.68±0.33 μg, 0.95±0.29 μg, 1.36±0.37 μg, 1.50±0.39 μg and 1.58±0.29 μg for taxi, subway, cycling, bus and walking, respectively. BC exposure level of walking was the lowest among all the traffic modes, but its inhalation dose was the highest. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Compliance with seat belt use in Benin City, Nigeria.

    PubMed

    Iribhogbe, Pius Ehiawaguan; Osime, Clement Odigie

    2008-01-01

    Trauma is a major cause of death and disability worldwide. A quarter of all fatalities due to injury occur due to road traffic crashes with 90% of the fatalities occurring in low- and medium-income countries. Poor compliance with the use of seat belts is a problem in many developing countries. The aim of this study was to evaluate the level of seatbelt compliance in motor vehicles in Benin City, Nigeria. A five-day, observational study was conducted in strategic locations in Benin City. The compliance rates of drivers, front seat passengers, and rear seat passengers in the various categories of vehicles were evaluated, and the data were subjected to statistical processing using the Program for Epidemiology. A total of 369 vehicles were observed. This consisted of 172 private cars, 64 taxis, 114 buses, 15 trucks, and four other vehicles. The seat belt compliance rate for drivers was 52.3%, front seat passengers 18.4%, and rear seat passengers 6.1%. Drivers of all categories of vehicles were more likely to use the seat belt compared to front seat passengers (p = 0.000) and rear seat passengers (p = 0.000). Drivers of private cars were more likely to use seat belts compared to taxi drivers (p = 0.000) and bus drivers (p = 0.000). Front seat passengers in private cars were more likely to use the seat belt compared to front seat passengers in taxis (p = 0.000) and buses (p = 0.000). Rear seat passengers in private cars also were more likely to use seat belts compared to rear seat passengers in taxis (p = 0.000) and buses (p = 0.000). Compliance with seat belt use in Benin City is low. Legislation, educational campaigns, and enforcement of seat belt use are needed.

  5. 14 CFR 298.70 - Public disclosure of data.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Public... available immediately following the Department's determination that the database is complete, but no earlier...

  6. 14 CFR 298.70 - Public disclosure of data.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Public... available immediately following the Department's determination that the database is complete, but no earlier...

  7. 14 CFR 298.70 - Public disclosure of data.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Public... available immediately following the Department's determination that the database is complete, but no earlier...

  8. 14 CFR 298.70 - Public disclosure of data.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Public... available immediately following the Department's determination that the database is complete, but no earlier...

  9. 14 CFR 298.70 - Public disclosure of data.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Public... available immediately following the Department's determination that the database is complete, but no earlier...

  10. Alaska Humans Factors Safety Study: The Southern Coastal Area

    NASA Technical Reports Server (NTRS)

    Chappell, Sheryl L.; Reynard, William (Technical Monitor)

    1995-01-01

    At the request of the Alaska Air Carriers Association, researchers from the NASA Aviation Safety Reporting System, at NASA Ames Research Center, conducted a study on aspects of safety in Alaskan Part 135 air taxi operations. An interview form on human factors safety issues was created by a representative team from the FAA-Alaska, NTSB-Alaska, NASA-ASRS, and representatives of the Alaska Air Carriers Association which was subsequently used in the interviews of pilots and managers. Because of the climate and operational differences, the study was broken into two geographical areas, the southern coastal areas and the northern portion of the state. This presentation addresses the southern coastal areas, specifically: Anchorage, Dillingham, King Salmon, Kodiak, Cold Bay, Juneau, and Ketchikan. The interview questions dealt with many of the potential pressures on pilots and managers associated with the daily air taxi operations in Alaska. The impact of the environmental factors such as the lack of available communication, navigation and weather information systems was evaluated. The results of this study will be used by government and industry working in Alaska. These findings will contribute important information on specific Alaska safety issues for eventual incorporation into training materials and policies that will help to assure the safe conduct of air taxi flights in Alaska.

  11. Tobacco consumption and secondhand smoke exposure in vehicles: a cross-sectional study

    PubMed Central

    Curto, Ariadna; Fernández, Esteve

    2011-01-01

    Objectives To estimate the prevalence of tobacco consumption and secondhand smoke (SHS) exposure in private cars, commercial vehicles and taxis in the city of Barcelona in Spain. Design setting and participants We carried out an observational cross-sectional study in 2011. We selected a systematic sample of 2442 private cars, commercial vehicles and taxis on 40 public roads regulated by traffic lights in all 10 districts of Barcelona. We calculated the prevalence rates and 95% CIs of smoking and SHS exposure in cars, and the corresponding ORs adjusting for the potential confounding variables. Results The prevalence of tobacco consumption was 5.5% (95% CI 4.6% to 6.4%) and was greater for commercial vehicles (9.8%; 95% CI 7.1% to 12.5%). The prevalence of SHS exposure was 5.2% (95% CI 3.8% to 6.6%) and 2.2% (95% CI 0.5% to 3.9%) of passengers under 14 years of age were exposed to SHS in vehicles. Conclusions This study highlights the need to promote public health measures aimed at reducing tobacco consumption in vehicles, especially in the presence of children, as well as enforcement of the current Spanish law against smoking in commercial vehicles and taxis. PMID:22119753

  12. Scaling Law of Urban Ride Sharing.

    PubMed

    Tachet, R; Sagarra, O; Santi, P; Resta, G; Szell, M; Strogatz, S H; Ratti, C

    2017-03-06

    Sharing rides could drastically improve the efficiency of car and taxi transportation. Unleashing such potential, however, requires understanding how urban parameters affect the fraction of individual trips that can be shared, a quantity that we call shareability. Using data on millions of taxi trips in New York City, San Francisco, Singapore, and Vienna, we compute the shareability curves for each city, and find that a natural rescaling collapses them onto a single, universal curve. We explain this scaling law theoretically with a simple model that predicts the potential for ride sharing in any city, using a few basic urban quantities and no adjustable parameters. Accurate extrapolations of this type will help planners, transportation companies, and society at large to shape a sustainable path for urban growth.

  13. Characteristics of propeller noise on an aircraft fuselage related to interior noise transmission

    NASA Technical Reports Server (NTRS)

    Mixson, J. S.; Barton, C. K.; Piersol, A. G.; Wilby, J. F.

    1979-01-01

    Exterior noise was measured on the fuselage of a twin-engine, light aircraft at four values of engine rpm in ground static tests and at forward speeds up to 36 m/s in taxi tests. Propeller noise levels, spectra, and correlations were determined using a horizontal array of seven flush-mounted microphones and a vertical array of four flush-mounted microphones in the propeller plane. The measured levels and spectra are compared with predictions based on empirical and analytical methods for static and taxi conditions. Trace wavelengths of the propeller noise field, obtained from point-to-point correlations, are compared with the aircraft sidewall structural dimensions, and some analytical results are presented that suggest the sensitivity of interior noise transmission to variations of the propeller noise characteristics.

  14. 14 CFR 25.25 - Weight limits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... weights corresponding to the airplane operating conditions (such as ramp, ground or water taxi, takeoff... conditions (such as zero fuel weight, center of gravity position and weight distribution) must be established...

  15. 14 CFR 25.25 - Weight limits.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... weights corresponding to the airplane operating conditions (such as ramp, ground or water taxi, takeoff... conditions (such as zero fuel weight, center of gravity position and weight distribution) must be established...

  16. 14 CFR 25.25 - Weight limits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... weights corresponding to the airplane operating conditions (such as ramp, ground or water taxi, takeoff... conditions (such as zero fuel weight, center of gravity position and weight distribution) must be established...

  17. Spatio-Temporal Characteristics of Resident Trip Based on Poi and OD Data of Float CAR in Beijing

    NASA Astrophysics Data System (ADS)

    Mou, N.; Li, J.; Zhang, L.; Liu, W.; Xu, Y.

    2017-09-01

    Due to the influence of the urban inherent regional functional distribution, the daily activities of the residents presented some spatio-temporal patterns (periodic patterns, gathering patterns, etc.). In order to further understand the spatial and temporal characteristics of urban residents, this paper research takes the taxi trajectory data of Beijing as a sample data and studies the spatio-temporal characteristics of the residents' activities on the weekdays. At first, according to the characteristics of the taxi trajectory data distributed along the road network, it takes the Voronoi generated by the road nodes as the research unit. This paper proposes a hybrid clustering method - based on grid density, which is used to cluster the OD (origin and destination) data of taxi at different times. Then combining with the POI data of Beijing, this research calculated the density of the POI data in the clustering results, and analyzed the relationship between the activities of residents in different periods and the functional types of the region. The final results showed that the residents were mainly commuting on weekdays. And it found that the distribution of travel density showed a concentric circle of the characteristics, focusing on residential areas and work areas. The results of cluster analysis and POI analysis showed that the residents' travel had experienced the process of "spatial relative dispersion - spatial aggregation - spatial relative dispersion" in one day.

  18. CO2, NOx, and particle emissions from aircraft and support activities at a regional airport.

    PubMed

    Klapmeyer, Michael E; Marr, Linsey C

    2012-10-16

    The goal of this research was to quantify emissions of carbon dioxide (CO(2)), nitrogen oxides (NO(x)), particle number, and black carbon (BC) from in-use aircraft and related activity at a regional airport. Pollutant concentrations were measured adjacent to the airfield and passenger terminal at the Roanoke Regional Airport in Virginia. Observed NO(x) emission indices (EIs) for jet-powered, commuter aircraft were generally lower than those contained in the International Civil Aviation Organization databank for both taxi (same as idle) and takeoff engine settings. NO(x) EIs ranged from 1.9 to 3.7 g (kg fuel)(-1) across five types of aircraft during taxiing, whereas EIs were consistently higher, 8.8-20.6 g (kg fuel)(-1), during takeoff. Particle number EIs ranged from 1.4 × 10(16) to 7.1 × 10(16) (kg fuel)(-1) and were slightly higher in taxi mode than in takeoff mode for four of the five types of aircraft. Diurnal patterns in CO(2) and NO(x) concentrations were influenced mainly by atmospheric conditions, while patterns in particle number concentrations were attributable mainly to patterns in aircraft activity. CO(2) and NO(x) fluxes measured by eddy covariance were higher at the terminal than at the airfield and were lower than found in urban areas.

  19. Reptile Embryos Lack the Opportunity to Thermoregulate by Moving within the Egg.

    PubMed

    Telemeco, Rory S; Gangloff, Eric J; Cordero, Gerardo A; Mitchell, Timothy S; Bodensteiner, Brooke L; Holden, Kaitlyn G; Mitchell, Sarah M; Polich, Rebecca L; Janzen, Fredric J

    2016-07-01

    Historically, egg-bound reptile embryos were thought to passively thermoconform to the nest environment. However, recent observations of thermal taxis by embryos of multiple reptile species have led to the widely discussed hypothesis that embryos behaviorally thermoregulate. Because temperature affects development, such thermoregulation could allow embryos to control their fate far more than historically assumed. We assessed the opportunity for embryos to behaviorally thermoregulate in nature by examining thermal gradients within natural nests and eggs of the common snapping turtle (Chelydra serpentina; which displays embryonic thermal taxis) and by simulating thermal gradients within nests across a range of nest depths, egg sizes, and soil types. We observed little spatial thermal variation within nests, and thermal gradients were poorly transferred to eggs. Furthermore, thermal gradients sufficiently large and constant for behavioral thermoregulation were not predicted to occur in our simulations. Gradients of biologically relevant magnitude have limited global occurrence and reverse direction twice daily when they do exist, which is substantially faster than embryos can shift position within the egg. Our results imply that reptile embryos will rarely, if ever, have the opportunity to behaviorally thermoregulate by moving within the egg. We suggest that embryonic thermal taxis instead represents a play behavior, which may be adaptive or selectively neutral, and results from the mechanisms for behavioral thermoregulation in free-living stages coming online prior to hatching.

  20. 14 CFR 23.235 - Operation on unpaved surfaces.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... structure of the airplane when the airplane is taxied on the roughest ground that may reasonably be expected in normal operation and when takeoffs and landings are performed on unpaved runways having the...

  1. 14 CFR 23.235 - Operation on unpaved surfaces.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... structure of the airplane when the airplane is taxied on the roughest ground that may reasonably be expected in normal operation and when takeoffs and landings are performed on unpaved runways having the...

  2. The Westport Connecticut Integrated Transit System : service and methods demonstration program

    DOT National Transportation Integrated Search

    1979-07-01

    Report evaluates the implementation, operations and impacts of the Westport Transit District's demonstration grant to examine the feasibility of combining shared ride taxi service and other paratransit services with conventional bus services. Report ...

  3. Greenhouse gas implications of fleet electrification based on big data-informed individual travel patterns.

    PubMed

    Cai, Hua; Xu, Ming

    2013-08-20

    Environmental implications of fleet electrification highly depend on the adoption and utilization of electric vehicles at the individual level. Past research has been constrained by using aggregated data to assume all vehicles with the same travel pattern as the aggregated average. This neglects the inherent heterogeneity of individual travel behaviors and may lead to unrealistic estimation of environmental impacts of fleet electrification. Using "big data" mining techniques, this research examines real-time vehicle trajectory data for 10,375 taxis in Beijing in one week to characterize the travel patterns of individual taxis. We then evaluate the impact of adopting plug-in hybrid electric vehicles (PHEV) in the taxi fleet on life cycle greenhouse gas emissions based on the characterized individual travel patterns. The results indicate that 1) the largest gasoline displacement (1.1 million gallons per year) can be achieved by adopting PHEVs with modest electric range (approximately 80 miles) with current battery cost, limited public charging infrastructure, and no government subsidy; 2) reducing battery cost has the largest impact on increasing the electrification rate of vehicle mileage traveled (VMT), thus increasing gasoline displacement, followed by diversified charging opportunities; 3) government subsidies can be more effective to increase the VMT electrification rate and gasoline displacement if targeted to PHEVs with modest electric ranges (80 to 120 miles); and 4) while taxi fleet electrification can increase greenhouse gas emissions by up to 115 kiloton CO2-eq per year with the current grid in Beijing, emission reduction of up to 36.5 kiloton CO2-eq per year can be achieved if the fuel cycle emission factor of electricity can be reduced to 168.7 g/km. Although the results are based on a specific public fleet, this study demonstrates the benefit of using large-scale individual-based trajectory data (big data) to better understand environmental implications

  4. 77 FR 55895 - Meeting: RTCA Program Management Committee (PMC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Enhanced Flight Vision System to Enable All-Weather Approach, Landing and Roll-Out to a Safe Taxi Speed... but limited to space availability. With the approval of the chairman, members of the public may...

  5. Transportation use in community-dwelling older adults: association with participation and leisure activities.

    PubMed

    Dahan-Oliel, Noémi; Mazer, Barbara; Gélinas, Isabelle; Dobbs, Bonnie; Lefebvre, Hélène

    2010-12-01

    This article presents a study that compared participation by elderly individuals living in the community according to primary transportation mode used, and estimated the association between transportation, personal factors, and environmental factors. Participants included 90 adults aged 65 and older (M=76.3 years; SD=7.7). They were classified according to their primary transportation mode: driver, passenger, public transport user, walk, or adapted transport/taxi user. Participation was measured with the Craig Handicap Assessment and Reporting Technique (CHART) and the Nottingham Leisure Questionnaire (NLQ). Overall, results indicated that drivers, public transport users, and walkers had higher participation levels compared to passengers and adapted transport/taxi users. This study suggests that clinicians should consider older adults' use of transportation in an attempt to encourage and maximize their participation.

  6. An Integrated Gate Turnaround Management Concept Leveraging Big Data/Analytics for NAS Performance Improvements

    NASA Technical Reports Server (NTRS)

    Chung, William; Chachad, Girish; Hochstetler, Ronald

    2016-01-01

    The Integrated Gate Turnaround Management (IGTM) concept was developed to improve the gate turnaround performance at the airport by leveraging relevant historical data to support optimization of airport gate operations, which include: taxi to the gate, gate services, push back, taxi to the runway, and takeoff, based on available resources, constraints, and uncertainties. By analyzing events of gate operations, primary performance dependent attributes of these events were identified for the historical data analysis such that performance models can be developed based on uncertainties to support descriptive, predictive, and prescriptive functions. A system architecture was developed to examine system requirements in support of such a concept. An IGTM prototype was developed to demonstrate the concept using a distributed network and collaborative decision tools for stakeholders to meet on time pushback performance under uncertainties.

  7. SARS Patients and Their Close Contacts

    MedlinePlus

    ... symptoms, limit your activities outside the home. Avoid public transportation (e.g., bus, taxi). Do not go to ... wear a mask, if tolerated. Do not use public transportation. Wash your hands often and well, especially after ...

  8. Commercial aircraft engine emissions characterization of in-use aircraft at Hartsfield-Jackson Atlanta International Airport

    DOT National Transportation Integrated Search

    2008-01-31

    The emissions from in-use commercial aircraft engines have been analyzed for selected gas-phase species and particulate characteristics using continuous extractive sampling 1-2 min downwind from operational taxi- and runways at Hartsfield-Jackson Atl...

  9. 14 CFR 25.233 - Directional stability and control.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... power to maintain a straight path. This may be shown during power-off landings made in conjunction with... during taxiing prior to takeoffs made in conjunction with other tests. [Doc. No. 5066, 29 FR 18291, Dec...

  10. Maintenance of Airport Visual Aid Facilities

    DOT National Transportation Integrated Search

    1982-08-26

    This advisory circular provides recommended guidelines for maintenance of : airport visual aid facilities. Since the function of such facilities is to : assist in the safe and efficient movement of aircraft during landing, takeoff, : and taxiing mane...

  11. Performance prediction of the Strong company's soft ground arrestor system using a numerical analysis.

    DOT National Transportation Integrated Search

    2009-10-01

    Air transportation has an outstanding safety record; however, accidents do occur. Aircraft accidents can occur while the aircraft is at cruise altitude or during land movements: taxiing, takeoff, and landing. Overruns occur when an aircraft is unable...

  12. High efficiency cabin air filter in vehicles reduces drivers' roadway particulate matter exposures and associated lipid peroxidation

    PubMed Central

    Shu, Shi; Lin, Yan; She, Jianwen; Ip, Ho Sai Simon; Qiu, Xinghua; Zhu, Yifang

    2017-01-01

    Commuters who spend long hours on roads are exposed to high levels of traffic related air pollutants (TRAPs). Despite some well-known multiple adverse effects of TRAPs on human health, limited studies have focused on mitigation strategies to reduce these effects. In this study, we measured fine particulate matter (PM2.5) and ultrafine particle (UFP) concentrations inside and outside 17 taxis simultaneously while they were driven on roadways. The drivers’ urinary monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and malondialdehyde (MDA) concentrations just before and right after the driving tests were also determined. Data were collected under three driving conditions (i.e. no mitigation (NM), window closed (WC), and window closed plus using high efficiency cabin air filters (WC+HECA)) for each taxi and driver. The results show that, compared to NM, the WC+HECA reduced in-cabin PM2.5 and UFP concentrations, by 37% and 47% respectively (p < 0.05), whereas the reductions on PAH exposures were insignificant. Although nonsignificant, a reduction of 17% was also observed in the drivers’ urinary MDA under WC+HECA. The MDA concentrations were found to be significantly associated with the in-cabin PM2.5 and UFP concentrations, suggesting the reduction of the drivers’ lipid peroxidation can be at least partially attributed to the PM2.5 and UFP reduction by WC+HECA. Overall, these results suggest HECA filters have potential to reduce particle levels inside taxis and protect drivers’ health. PMID:29176859

  13. High efficiency cabin air filter in vehicles reduces drivers' roadway particulate matter exposures and associated lipid peroxidation.

    PubMed

    Yu, Nu; Shu, Shi; Lin, Yan; She, Jianwen; Ip, Ho Sai Simon; Qiu, Xinghua; Zhu, Yifang

    2017-01-01

    Commuters who spend long hours on roads are exposed to high levels of traffic related air pollutants (TRAPs). Despite some well-known multiple adverse effects of TRAPs on human health, limited studies have focused on mitigation strategies to reduce these effects. In this study, we measured fine particulate matter (PM2.5) and ultrafine particle (UFP) concentrations inside and outside 17 taxis simultaneously while they were driven on roadways. The drivers' urinary monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) and malondialdehyde (MDA) concentrations just before and right after the driving tests were also determined. Data were collected under three driving conditions (i.e. no mitigation (NM), window closed (WC), and window closed plus using high efficiency cabin air filters (WC+HECA)) for each taxi and driver. The results show that, compared to NM, the WC+HECA reduced in-cabin PM2.5 and UFP concentrations, by 37% and 47% respectively (p < 0.05), whereas the reductions on PAH exposures were insignificant. Although nonsignificant, a reduction of 17% was also observed in the drivers' urinary MDA under WC+HECA. The MDA concentrations were found to be significantly associated with the in-cabin PM2.5 and UFP concentrations, suggesting the reduction of the drivers' lipid peroxidation can be at least partially attributed to the PM2.5 and UFP reduction by WC+HECA. Overall, these results suggest HECA filters have potential to reduce particle levels inside taxis and protect drivers' health.

  14. The sea urchin Diadema africanum uses low resolution vision to find shelter and deter enemies.

    PubMed

    Kirwan, John D; Bok, Michael J; Smolka, Jochen; Foster, James J; Hernández, José Carlos; Nilsson, Dan-Eric

    2018-05-08

    Many sea urchins can detect light on their body surface and some species are reported to possess image-resolving vision. Here we measure the spatial resolution of vision in the long-spined sea urchin Diadema africanum , using two different visual responses: a taxis towards dark objects and an alarm response of spine-pointing towards looming stimuli. For the taxis response we used visual stimuli, which were isoluminant to the background, to discriminate spatial vision from phototaxis. Individual animals were placed in the centre of a cylindrical arena under bright down-welling light, with stimuli of varying angular width placed on the arena wall at pseudorandom directions from the centre. We tracked the direction of movement of individual animals in relation to the stimuli to determine whether the animals oriented towards the stimulus. We found that D. africanum responds by taxis towards isoluminant stimuli with a spatial resolution in the range 29°-69°. This corresponds to a theoretical acceptance angle of 38°-89°, assuming a contrast threshold of 10%. The visual acuity of the alarm response of D. africanum was tested by exposing animals to different sized dark looming and appearing stimuli on a monitor. We found that D. africanum displays a spine-pointing response to appearing black circles of 13°-25° angular width, corresponding to an acceptance angle of 60°-116°, assuming the same contrast threshold as above. © 2018. Published by The Company of Biologists Ltd.

  15. Interspecific reconstitution of maltose transport and chemotaxis in Escherichia coli with maltose-binding protein from various enteric bacteria.

    PubMed Central

    Dahl, M K; Manson, M D

    1985-01-01

    In Escherichia coli, the periplasmic maltose-binding protein (MBP), the product of the malE gene, is the primary recognition component of the transport system for maltose and maltodextrins. It is also the maltose chemoreceptor, in which capacity it interacts with the signal transducer Tar (taxis to aspartate and some repellents). In studies of the maltose system in other members of the family Enterobacteriaceae, we found that MBP is produced by Salmonella typhimurium, Klebsiella pneumoniae, Enterobacter aerogenes, and Serratia marcescens. MBP from all of these species cross-reacted with antibody against the E. coli protein and had a similar molecular weight (about 40,000). The Shigella flexneri and Proteus mirabilis strains we examined did not synthesize MBP. The isoelectric points of MBP from different species varied from the acid extreme of E. coli (4.8) to the basic extreme of E. aerogenes (8.9). All species with MBP transported maltose with high affinity, although the Vmax for K. pneumoniae was severalfold lower than that for the other species. Maltose chemotaxis was observed only in E. coli and E. aerogenes. In S. typhimurium LT2, Tar was completely inactive in maltose taxis, although it signaled normally in response to aspartate. MBP isolated from all five species could be used to reconstitute maltose transport and taxis in a delta malE strain of E. coli after permeabilization of the outer membrane with calcium. Images PMID:3905762

  16. Annual review of aircraft accident data : U.S. air carrier operations calendar year 1997

    DOT National Transportation Integrated Search

    2002-01-24

    This publication presents the record of aviation accidents involving revenue operations of U.S. : air carriers including commuter air carriers and on-demand air taxis for calendar year 1997. : The report is divided into three major sections according...

  17. Expedition 9 Landing

    NASA Image and Video Library

    2004-10-24

    Women dressed in traditional Kazak clothing pose for a photo after presenting the returning Expedition 9 and taxi flight crew members with gifts at the airport in Kustanay, Kazakhstan, Sunday, October 24, 2004. Photo Credit: (NASA/Bill Ingalls)

  18. Pre-Demonstration Activities of the Westport Integrated Transit System

    DOT National Transportation Integrated Search

    1977-07-01

    In August 1976 the Urban Mass Transportation Administration of the U.S. Department of Transportation awarded a demonstration grant to the Westport Transit District (WTD) to examine the feasibility of combining shared-ride taxi service and other parat...

  19. 5 CFR 2634.304 - Gifts and reimbursements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... at a local restaurant—$120. 2. Round-trip taxi fare to meet donor at the restaurant—$25. 3. Dinner at... actual cost from the caterer, restaurant, or similar source. (f) Waiver rule in the case of certain gifts...

  20. Making the Difference : Transportation Alternatives for Elderly and Handicapped Persons

    DOT National Transportation Integrated Search

    1979-08-01

    This report contains project summaries of four examples of public transportation services for Elderly and Handicapped persons: the LIFT Project in Portland, OR; Roanoke Agencies Dial-A-Ride (RADAR) in Roanoke, VA; the Reduced Taxi Rate Program (RTR) ...

  1. Results of aircraft open-loop tests of an experimental magnetic leader cable system for guidance during roll-out and turnoff

    NASA Technical Reports Server (NTRS)

    Bundick, W. Thomas; Middleton, David B.; Poole, William L.

    1990-01-01

    An experimental magnetic leader cable (MLC) system designed to measure aircraft lateral displacement from centerline and heading relative to centerline during rollout, turnoff, and taxi was tested at NASA's Wallops Flight Facility using NASA's Transport System Research Vehicle (TSRV), a modified B-737. The MLC system consisted of ground equipment that produced a magnetic field about a wire along runway centerline and airborne equipment that detected the strength and direction of this field and computed displacement and heading. Results of these tests indicate that estimates of aircraft displacement from centerline produced by the magnetic leader cable system using either of the two algorithms appear to be adequate for use by an automatic control system during rollout, turnoff, and taxi. Estimates of heading, however, are not sufficiently accurate for use, probably because of distortion of the magnetic field by the metal aircraft.

  2. 75 FR 18567 - Agency Information Collection; Activity Under OMB Review; Omnibus Household Survey Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ...'s strategic goals (safety, reduced congestion, global connectivity, environmental stewardship and..., as well as other governmental agencies, to survey the public about current transportation issues, and... transit (subway, streetcar, or light rail) Commuter rail Water transportation (taxis, ferries, ships...

  3. Paratransit Labor Issues

    DOT National Transportation Integrated Search

    1978-02-01

    All paratransit services are labor intensive, second only to conventional taxis among transportation modes. As such, the manner in which the service is provided, the role of the labor force, and, in particular, the compensation afforded to drivers, h...

  4. Sonotropic effects of commercial air transport sound on birds.

    DOT National Transportation Integrated Search

    1962-03-01

    The Electra sound spectrum contains an audible chirp which appears identical in frequency and wave form to the chirp of field crickets. Field observations strongly indicate the sound of the taxiing Electra exerts an attraction for starlings, and poss...

  5. Transport emissions: All hail robocabs

    NASA Astrophysics Data System (ADS)

    Brown, Austin

    2015-09-01

    Connected and automated vehicles enable new business models, such as self-driving taxis, that could transform transportation. These models have the potential to reduce energy consumption and greenhouse-gas emissions, but only if they are developed with energy use in mind.

  6. Milwaukee County User-Side Subsidy Program : A Case Study

    DOT National Transportation Integrated Search

    1982-09-01

    Milwaukee County, Wisconsin, instituted a user-side subsidy program in June 1978 for handicapped users of taxi and chair-car services. The program is funded entirely by county and state contributions. A distinctive feature of the program is that, unl...

  7. Aviation Environmental Design Tool (AEDT 2b)

    DOT National Transportation Integrated Search

    2015-10-01

    The Aviation Environmental Design Tool (AEDT) is a part of FAAs NextGen environmental and modeling toolsuite. It provides a means of modeling aircraft in four dimensions for all phases of flight including taxi, takeoff/landing, and cruise. It is s...

  8. Confusion in Using Pre-Departure Clearances

    DOT National Transportation Integrated Search

    1996-12-20

    In 1990, the FAA implemented the Pre-Departure Clearance (PDC) program at a : number of U.S. airports. This system allows pilots to obtain IFR clearances : through aircraft ACARS units prior to taxi-out, thus eliminating the need for : verbal communi...

  9. 75 FR 65049 - Agency Information Collection; Activity Under OMB Review; Omnibus Household Survey Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... light of the DOT's strategic goals (safety, reduced congestion, global connectivity, environmental... issues, and Provide national estimates of transportation mode usage. Each version of the OHS will focus... owned vehicle; Taxi; Rail transit (subway, streetcar, or light rail); Commuter rail; Water...

  10. Mitigating runway incursions : a safety benefits assessment of airport surface moving map displays

    DOT National Transportation Integrated Search

    2010-01-01

    Airport surface moving maps vary in the capabilities provided (e.g., the depiction of ownship position and/or traffic, the presentation of taxi route, and indicating or alerting the potential for runway incursions). The purpose of this effort was to ...

  11. The use of large scale datasets for understanding traffic network state.

    DOT National Transportation Integrated Search

    2013-09-01

    The goal of this proposal is to develop novel modeling techniques to infer individual activity patterns from the large scale cell phone : datasets and taxi data from NYC. As such this research offers a paradigm shift from traditional transportation m...

  12. The Conic Sections in Taxicab Geometry: Some Investigations for High School Students.

    ERIC Educational Resources Information Center

    Prevost, Fernand J.

    1998-01-01

    Introduces the taxicab metric which is practical for many applications and helps students pursue interesting investigations while deepening their understanding of familiar topics. Uses the taxicab metric to explore the circle, ellipse, and hyperbola in the plane called TaxiLand. (ASK)

  13. How to Restore Plant's Taxis in Microgravity

    NASA Astrophysics Data System (ADS)

    Gorgolewski, S.

    All plants respond to gravity, yet in micro-gravity not all plants will grow the way as they do on the Earth. Successful space experiments with plants grown from seed to seed, were performed (to the best of my knowledge) with non electrotropic plants. Such plants use phototropism instead of the gravitropism. The electrotropic plants have been successfully grown in phytotron and in a greenhouse. We used the electric field to direct their growth where we want them to grow. Normally the ground or soil is negatively charged, and plants grow upwards towards positive charges in the air or the anode (positive electrode) in plant growth chambers. In reversed field polarization with "ground positive" the lettuce grows down-wards. In horizontal electric fields it grows horizontally again towards positively charged field generating conducting plate. This is at the first glance a very surprising effect even to the physicist. But one has to remember the most important fact that the electromagnetic forces are a factor of 1038 times stronger than the gravitational force. On the Earth the gravity acts on the entire plant, but the electrical field acts only on ions which are distributed on the surface of leaves, sprouts or stem tips. The ions are directed so very much strongly (1038 times) by the electrical field, than by gravity. The electric field lines guide the concentrations of ions to follow the field lines rendering the plants electrotropic and shaping their growth pattern. There is also a clear positive dependence of the rate of plant growth on field strength and crop yield. This is why it is so important to know which plants are electrotropic not only for use in space but also in greenhouse plant cultures. It is very much cheaper to select the electrotropic plant here, and not in space experiments for best cost efficiency. Special light weight plant growth chambers have been designed and very successfully used in terrestrial experiments. We can make the plant growth chambers very much lighter for space applications. We do not need to send them assembled into space, but rather make them foldable. Then we do not strain the plant growth chambers by vibrations and about 10 times stronger accelerations than gravity during launch, besides they are also not gravitationally loaded in space. We deploy them by stretching or inflating, them and suspend them using springs to get them into the needed shape and position. Some considerations have been given to some designs of space borne plant growth chambers. We pay special attention to secure the very important advantages of light weight and low cost so vital in space applications.

  14. Human Mars Mission Performance Crew Taxi Profile

    NASA Technical Reports Server (NTRS)

    Duaro, Vince A.

    1999-01-01

    Using the results from Integrated Mission Program (IMP), a simulation language and code used to model present and future Earth Moon, or Mars missions, this report presents six different case studies of a manned Mars mission. The mission profiles, timelines, propellant requirements, feasibility and perturbation analysis is presented for two aborted, two delayed rendezvous, and two normal rendezvous cases for a future Mars mission.

  15. 14 CFR 294.33 - Compliance with the regulations of the Federal Aviation Administration.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Federal Aviation Administration. 294.33 Section 294.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.33 Compliance with the regulations of the Federal Aviation...

  16. 14 CFR 294.33 - Compliance with the regulations of the Federal Aviation Administration.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Federal Aviation Administration. 294.33 Section 294.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.33 Compliance with the regulations of the Federal Aviation...

  17. 14 CFR 294.33 - Compliance with the regulations of the Federal Aviation Administration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Federal Aviation Administration. 294.33 Section 294.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.33 Compliance with the regulations of the Federal Aviation...

  18. 14 CFR 294.33 - Compliance with the regulations of the Federal Aviation Administration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Federal Aviation Administration. 294.33 Section 294.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.33 Compliance with the regulations of the Federal Aviation...

  19. 14 CFR 294.33 - Compliance with the regulations of the Federal Aviation Administration.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Federal Aviation Administration. 294.33 Section 294.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS General Rules for Registrants § 294.33 Compliance with the regulations of the Federal Aviation...

  20. Low Life Cycle Cost Design Study for Paratransit Vehicles

    DOT National Transportation Integrated Search

    1978-07-01

    This report summarizes the work performed on the Low Life Cycle Cost (LLCC) paratransit vehicle contract. The program was structured to provide a design of a vehicle suitable for taxi paratransit usage and optimized for LLCC to the end user. This eff...

  1. Comparison of Fuel Economy and Emissions for Diesel and Gasoline Powered Taxicabs

    DOT National Transportation Integrated Search

    1979-07-01

    The objective of this study was to assess potential improvements in fuel economy and exhaust emissions by dieselization of the taxi fleet in a large urban area. Sixty-six diesel powered taxicabs and an equal number of gasoline powered cabs were opera...

  2. 75 FR 5370 - Notice of Request for Clearance of an Information Collection: Omnibus Household Survey Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-02

    ... transportation system in light of the DOT's strategic goals (safety, reduced congestion, global connectivity... transportation issues, and provide national estimates of transportation mode usage. Each version of the OHS will... transit (subway, streetcar, or light rail) Commuter rail Water transportation (taxis, ferries, ships...

  3. 14. Photocopy of historic photograph (original photograph on file at ...

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

    14. Photocopy of historic photograph (original photograph on file at Fairchild Air Force Museum, Spokane, WA) Photographer unknown, date unknown BOMBER ALERT FACILITY, INTERIOR, SLEEPING QUARTERS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  4. Aviation safety : preliminary information on aircraft icing and winter operations, Wednesday, February 24, 2010.

    DOT National Transportation Integrated Search

    2010-02-24

    Ice formation on aircraft can disrupt the smooth flow of air over the wings and prevent the aircraft from taking off or decrease the pilots ability to maintain control of the aircraft. Taxi and landing operations can also be risky in winter weathe...

  5. 21. Photocopy of engineering drawing, April 10, 1958 (original drawing ...

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

    21. Photocopy of engineering drawing, April 10, 1958 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). READINESS CREW BUILDING, RAMP DETAILS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  6. 25. Photocopy of engineering drawing, January, 1988 (original drawing located ...

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

    25. Photocopy of engineering drawing, January, 1988 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). EXTERIOR ELEVATIONS (northeast and southeast) - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  7. 26. Photocopy of engineering drawing, March 3, 1988 (original drawing ...

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

    26. Photocopy of engineering drawing, March 3, 1988 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). EXTERIOR ELEVATIONS (southwest and northwest) - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  8. 20. Photocopy of engineering drawing, April 10, 1958 (original drawing ...

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

    20. Photocopy of engineering drawing, April 10, 1958 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). READINESS CREW BUILDING, ELEVATIONS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  9. A Brief Investigation of the Hydrodynamic Characteristics of a 1/13.33-Scale Powered Dynamic Model of a Preliminary Design of the Martin XP6M-1 Flying Boat, TED No. NACA DE-385

    NASA Technical Reports Server (NTRS)

    Blanchard, Ulysse J.

    1953-01-01

    The hydrodynamic characteristics of a preliminary design of the Martin XP6M-1 flying boat have been determined. Longitudinal stability during take-off and landing, resistance of the complete model, and behavior during taxiing and landing in rough water are presented.

  10. Phoenix Transit Sunday Dial-a-Ride

    DOT National Transportation Integrated Search

    1983-06-01

    A local taxi operator began subsidized dial-a-ride service in Phoenix, AR, when the city found that Sunday fixed-route transit service would be more costly. Regular cabs and wheelchair vans are billed at a fixed hourly rate less fares collected. Over...

  11. 14 CFR 294.86 - Industrial/agricultural/other nontransport air operations prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Industrial/agricultural/other nontransport air operations prohibited. 294.86 Section 294.86 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS...

  12. 14 CFR 294.86 - Industrial/agricultural/other nontransport air operations prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Industrial/agricultural/other nontransport air operations prohibited. 294.86 Section 294.86 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS...

  13. 14 CFR 294.85 - Charterworthiness standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Charterworthiness standards. 294.85 Section 294.85 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  14. Television's New Humane Collectivity.

    ERIC Educational Resources Information Center

    Schrag, Robert L.; And Others

    1981-01-01

    Analyzes "Taxi,""Barney Miller,""Lou Grant," and "M*A*S*H" in terms of three fantasy themes: the realization of significant others, the alliance in action, and membership into personhood. From these themes emerges a rhetorical vision of the new humane collectivity. (PD)

  15. 14 CFR 294.85 - Charterworthiness standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Charterworthiness standards. 294.85 Section 294.85 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  16. Motility of magnetotactic bacteria/MTB to Geomagnetic fields

    NASA Astrophysics Data System (ADS)

    Hidajatullah-Maksoed, Fatahillah

    2016-03-01

    Bacteria with motility directed by a local geomagnetic fields have been observed in marine sediments'' discussed by R. Blakemore, 1975. Magnetotactic bacteria/MTB discovered in 1963 by Salvatore Bellini. For ``off-axis electron holography in the transmission electron microscope was used to correlates the physical & magnetic microstructure of magnetite nanocrystals in magnetotactic bacteria'' sought ``single-domain magnetite in hemopelagic sediments'' from JF Stolz. Otherwise, for potential source of bioproducts- product meant from result to multiplier -of magnetotactic bacteria[ACV Araujo, et.al, 2014 ] of marine drugs retrieved the `measurement of cellular chemotaxis with ECIS/Taxis, from KM Pietrosimone, 2012, whereas after ``earth magnetic field role on small living models'' are other interpretation of ``taxis'' as a movement of a cell instead usual ``tax'' for yew's taxus cuspidate, hired car & taxes in financial realms. Acknowledgements to HE. Mr. H. TUK SETYOHADI, Jl. Sriwijaya Raya 3, South-Jakarta, INDONESIA.

  17. Reduction of Weather-Related Terminal Area Delays in the Free-Flight Era

    NASA Technical Reports Server (NTRS)

    Johnson, Sally C.; Chin, David K.; Rovinsky, Robert B.; Kostiuk, Peter F.; Lee, David A.; Hemm, Robert V.; Wingrove, Earl R., III

    1996-01-01

    While much of the emphasis of the free-flight movement has been concentrated on reducing en-route delays, airport capacity is a major bottleneck in the current airspace system, particularly during bad weather. According to the Air Transport Association (ATA) Air Carrier Delay Reports, ground delays (gate-hold, taxi-in, and taxi-out) comprise 75 percent of total delays. It is likely that the projected steady growth in traffic will only exacerbate these losses. Preliminary analyses show that implementation of the terminal area technologies and procedures under development in NASA s Terminal Area Productivity program can potentially save the airlines at least $350M annually in weather-related delays by the year 2005 at Boston Logan and Detroit airports alone. This paper briefly describes the Terminal Area Productivity program, outlines the costhenefit analyses that are being conducted in support of the program, and presents some preliminary analysis results.

  18. Using Computational Cognitive Modeling to Diagnose Possible Sources of Aviation Error

    NASA Technical Reports Server (NTRS)

    Byrne, M. D.; Kirlik, Alex

    2003-01-01

    We present a computational model of a closed-loop, pilot-aircraft-visual scene-taxiway system created to shed light on possible sources of taxi error. Creating the cognitive aspects of the model using ACT-R required us to conduct studies with subject matter experts to identify experiential adaptations pilots bring to taxiing. Five decision strategies were found, ranging from cognitively-intensive but precise, to fast, frugal but robust. We provide evidence for the model by comparing its behavior to a NASA Ames Research Center simulation of Chicago O'Hare surface operations. Decision horizons were highly variable; the model selected the most accurate strategy given time available. We found a signature in the simulation data of the use of globally robust heuristics to cope with short decision horizons as revealed by errors occurring most frequently at atypical taxiway geometries or clearance routes. These data provided empirical support for the model.

  19. Localization of human T-cell lymphotropic virus type II Tax protein is dependent upon a nuclear localization determinant in the N-terminal region.

    PubMed

    Turci, Marco; Romanelli, Maria Grazia; Lorenzi, Pamela; Righi, Paola; Bertazzoni, Umberto

    2006-01-03

    Human T-cell lymphotropic viruses (HTLV) types I and II are closely related oncogenic retroviruses that have been associated with lymphoproliferative and neurological disorders. The proviral genome encodes a trans-regulatory Tax protein that activates viral genes and upregulates various cellular genes involved in both cell growth and transformation. Tax proteins of HTLV-I (Tax-I) and HTLV-II (Tax-II) exhibit more than 77% aa homology and expression of either Tax-I or Tax-II is sufficient for immortalization of cultured T lymphocytes. Tax-I shuttles from the nucleus to the cytoplasm and accumulates within the nucleus, whereas Tax-II is found mainly in the cytoplasm. In the present study we have used recombinant vectors to analyze the size and structure of the nuclear localization domain within the Tax-II protein sequence. The Tax-II protein was expressed in HeLa cells either as the complete protein, or regions thereof, that were individually fused to the green fluorescent protein (GFP). Immunoblot analysis of the fused Tax-II products confirmed their expression and size. Fluorescence microscopy studies indicated that the complete Tax-II as well as N-truncated forms presented a punctuate cytoplasmic distribution and that a nuclear localization determinant is confined to within the first 60 aa of Tax-II. Accordingly, site directed mutagenesis and deletion of specific sequences within the first 60 aa showed that the nuclear determinant lies within the first 41 residues of Tax-II. These results point to a direct involvement of the amino-terminal residues of Tax-II protein in determining its nuclear functionality.

  20. 47 CFR 87.5 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...; (b) aircraft services (e.g. parking, storage, tie-downs); (c) aircraft maintenance or sales; (d) electronics equipment maintenance or sales; (e) aircraft rental, air taxi service or flight instructions; and... permit the pilot to check a radionavigation system aboard the aircraft prior to takeoff. Radionavigation...

  1. 47 CFR 87.5 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...; (b) aircraft services (e.g. parking, storage, tie-downs); (c) aircraft maintenance or sales; (d) electronics equipment maintenance or sales; (e) aircraft rental, air taxi service or flight instructions; and... permit the pilot to check a radionavigation system aboard the aircraft prior to takeoff. Radionavigation...

  2. 47 CFR 87.5 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...; (b) aircraft services (e.g. parking, storage, tie-downs); (c) aircraft maintenance or sales; (d) electronics equipment maintenance or sales; (e) aircraft rental, air taxi service or flight instructions; and... permit the pilot to check a radionavigation system aboard the aircraft prior to takeoff. Radionavigation...

  3. 14 CFR 298.62 - Reporting of financial data.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Reporting... used to report financial data for the overall or system operations of the carrier. At the option of the... services. This category shall include revenue derived from scheduled service operations, revenue derived...

  4. 23. Photocopy of engineering drawing, April 10, 1958 (original drawing ...

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

    23. Photocopy of engineering drawing, April 10, 1958 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). READINESS CREW BUILDING, UPPER FLOOR PLANS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  5. 22. Photocopy of engineering drawing, April 10, 1958 (original drawing ...

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

    22. Photocopy of engineering drawing, April 10, 1958 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). READINESS CREW BUILDING, LOWER FLOOR PLANS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  6. 49 CFR 374.309 - Terminal facilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Passenger security. All terminals and stations must provide adequate security for passengers and their attendants and be regularly patrolled. (b) Outside facilities. At terminals and stations that are closed when... accommodations, and telephone numbers for local taxi service and police. (c) Maintenance. Terminals shall be...

  7. 14 CFR 298.53 - Suspension or revocation of authority.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Suspension or revocation of authority. 298.53 Section 298.53 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS...

  8. 14 CFR 294.81 - Local traffic prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Local traffic prohibited. 294.81 Section 294.81 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  9. 14 CFR 298.62 - Reporting of financial data.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Reporting of financial data. 298.62 Section 298.62 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Reporting...

  10. 14 CFR 294.83 - Compliance with certain international agreements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Compliance with certain international agreements. 294.83 Section 294.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and...

  11. 14 CFR 294.50 - Cancellation, revocation, or suspension of registration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Cancellation, revocation, or suspension of registration. 294.50 Section 294.50 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Cancellation of Registration...

  12. 14 CFR 294.50 - Cancellation, revocation, or suspension of registration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Cancellation, revocation, or suspension of registration. 294.50 Section 294.50 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Cancellation of Registration...

  13. 14 CFR 298.34 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false [Reserved] 298.34 Section 298.34 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on...

  14. 14 CFR 298.60 - General reporting instructions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false General reporting instructions. 298.60 Section 298.60 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Reporting...

  15. 14 CFR 294.81 - Local traffic prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Local traffic prohibited. 294.81 Section 294.81 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  16. 14 CFR 298.60 - General reporting instructions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false General reporting instructions. 298.60 Section 298.60 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Reporting...

  17. 14 CFR 298.53 - Suspension or revocation of authority.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Suspension or revocation of authority. 298.53 Section 298.53 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS...

  18. 14 CFR 294.83 - Compliance with certain international agreements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Compliance with certain international agreements. 294.83 Section 294.83 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and...

  19. 14 CFR 298.34 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false [Reserved] 298.34 Section 298.34 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Limitations and Conditions on...

  20. 14 CFR 298.50 - Application.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Application. 298.50 Section 298.50 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations...

  1. 14 CFR 294.87 - Compliance with Canadian licenses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Compliance with Canadian licenses. 294.87 Section 294.87 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  2. 14 CFR 298.50 - Application.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Application. 298.50 Section 298.50 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations...

  3. 14 CFR 294.87 - Compliance with Canadian licenses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Compliance with Canadian licenses. 294.87 Section 294.87 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of...

  4. 14 CFR 294.84 - Air competency requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Air competency requirements. 294.84 Section... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of This Part § 294.84 Air competency requirements. Registrants shall conform to the airworthiness and...

  5. 14 CFR 294.84 - Air competency requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Air competency requirements. 294.84 Section... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of This Part § 294.84 Air competency requirements. Registrants shall conform to the airworthiness and...

  6. 14 CFR 294.84 - Air competency requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Air competency requirements. 294.84 Section... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of This Part § 294.84 Air competency requirements. Registrants shall conform to the airworthiness and...

  7. CANOLA CROP TAKES UP SELENIUM PROVIDES BIOFUEL AND FEED SUPPLEMENT

    USDA-ARS?s Scientific Manuscript database

    Many of the Brassica plant taxi that are candidates for phytoremediation of selenium also produce products that be used for refining into biodiesel, as well as selenium enriched animal feeds. These include canola (Brassica napus) that is planted in the Westside soils of central California (Oxalis si...

  8. 14 CFR 294.84 - Air competency requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Air competency requirements. 294.84 Section... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of This Part § 294.84 Air competency requirements. Registrants shall conform to the airworthiness and...

  9. 14 CFR 294.84 - Air competency requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air competency requirements. 294.84 Section... PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Terms, Conditions, and Limitations of This Part § 294.84 Air competency requirements. Registrants shall conform to the airworthiness and...

  10. 24. Photocopy of engineering drawing, August 17, 1965 (original drawing ...

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

    24. Photocopy of engineering drawing, August 17, 1965 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering Vault). 2080 READINESS CREW, COVERED WALKWAYS, PLAN AND DETAILS - Fairchild Air Force Base, Bomber Alert Facility, 803G South Taxi Way, Spokane, Spokane County, WA

  11. Vice President Mike Pence Visits Kennedy Space Center

    NASA Image and Video Library

    2017-07-06

    Air Force Two, carrying Vice President Mike Pence, taxis on the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. During his visit to Kennedy, the Vice President spoke inside the iconic Vehicle Assembly Building, where he thanked employees for advancing American leadership in space.

  12. 77 FR 55893 - Agency Requests for Renewal of a Previously Approved Information Collection: Exemptions for Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Previously Approved Information Collection: Exemptions for Air Taxi Operations AGENCY: Office of the... public comments about our intention to request the Office of Management and Budget (OMB)'s approval to..., (202) 366-9721, Office of Aviation Analysis, Office of the Secretary, U.S. Department of Transportation...

  13. 75 FR 1405 - National Park Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-11

    ...: Notice of availability of the Record of Decision for the General Management Plan/Environmental Impact...) announces the availability of a Record of Decision (ROD) for the General Management Plan/Environmental... Arch grounds by water taxi. A new external and internal visitor transportation system will be designed...

  14. 77 FR 44307 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-27

    ... Required to Collect PFC's: Air taxi/ commercial operators filing FAA Form 1800-31. Determination: Approved... Air Carriers Not Required to Collect PFC's: Nonscheduled/ on-demand air carriers filing FAA Form 1800... Carriers Not Required to Collect PFC's: None. Brief Description of Projects Approved for Collection and Use...

  15. 14 CFR 294.61 - Waivers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Waivers. 294.61 Section 294.61 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Authorizations and Waivers § 294.61 Waivers. The Department...

  16. 14 CFR 294.22 - Notification to the Department of change in operations or identifying information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Notification to the Department of change in operations or identifying information. 294.22 Section 294.22 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS...

  17. 14 CFR 294.61 - Waivers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Waivers. 294.61 Section 294.61 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS CANADIAN CHARTER AIR TAXI OPERATORS Authorizations and Waivers § 294.61 Waivers. The Department...

  18. 14 CFR 298.80 - Enforcement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Enforcement. 298.80 Section 298.80 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Violations § 298.80 Enforcement. In...

  19. 14 CFR 298.66 - Reporting exemption for State collection of data.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Reporting exemption for State collection of data. 298.66 Section 298.66 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS...

  20. 14 CFR 298.32 - Limitations on operations to eligible places.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Limitations on operations to eligible places. 298.32 Section 298.32 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS...