Origin of inorganic and organic components of PM2.5 in subway stations of Barcelona, Spain.

PubMed

Martins, Vânia; Moreno, Teresa; Minguillón, María Cruz; van Drooge, Barend L; Reche, Cristina; Amato, Fulvio; de Miguel, Eladio; Capdevila, Marta; Centelles, Sonia; Querol, Xavier

2016-01-01

The present work assesses indoor air quality in stations of the Barcelona subway system. PM2.5 concentrations on the platforms of 4 subway stations were measured during two different seasons and the chemical composition was determined. A Positive Matrix Factorization analysis was performed to identify and quantify the contributions of major PM2.5 sources in the subway stations. Mean PM2.5 concentrations varied according to the stations design and seasonal periods. PM2.5 was composed of haematite, carbonaceous aerosol, crustal matter, secondary inorganic compounds, trace elements, insoluble sulphate and halite. Organic compounds such as PAHs, nicotine, levoglucosan and aromatic musk compounds were also identified. Subway PM2.5 source comprised emissions from rails, wheels, catenaries, brake pads and pantographs. The subway source showed different chemical profiles for each station, but was always dominated by Fe. Control actions on the source are important for the achievement of better air quality in the subway environment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Indoor-air microbiome in an urban subway network: diversity and dynamics.

PubMed

Leung, Marcus H Y; Wilkins, David; Li, Ellen K T; Kong, Fred K F; Lee, Patrick K H

2014-11-01

Subway systems are indispensable for urban societies, but microbiological characteristics of subway aerosols are relatively unknown. Previous studies investigating microbial compositions in subways employed methodologies that underestimated the diversity of microbial exposure for commuters, with little focus on factors governing subway air microbiology, which may have public health implications. Here, a culture-independent approach unraveling the bacterial diversity within the urban subway network in Hong Kong is presented. Aerosol samples from multiple subway lines and outdoor locations were collected. Targeting the 16S rRNA gene V4 region, extensive taxonomic diversity was found, with the most common bacterial genera in the subway environment among those associated with skin. Overall, subway lines harbored different phylogenetic communities based on α- and β-diversity comparisons, and closer inspection suggests that each community within a line is dependent on architectural characteristics, nearby outdoor microbiomes, and connectedness with other lines. Microbial diversities and assemblages also varied depending on the day sampled, as well as the time of day, and changes in microbial communities between peak and nonpeak commuting hours were attributed largely to increases in skin-associated genera in peak samples. Microbial diversities within the subway were influenced by temperature and relative humidity, while carbon dioxide levels showed a positive correlation with abundances of commuter-associated genera. This Hong Kong data set and communities from previous studies conducted in the United States formed distinct community clusters, indicating that additional work is required to unravel the mechanisms that shape subway microbiomes around the globe. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Chlorine Dioxide Fumigation of Subway Materials ...

EPA Pesticide Factsheets

Report This bench scale study observed that a six (6) log reduction in viable spores of a suitable B. anthracis surrogate can be obtained for subway infrastructure materials by ClO2 fumigation if the temperature is at or above 24 °C combined with RH greater than 75%. No six log reduction in viable spores was observed at realistic (winter) temperatures in a subway environment (11-13 °C and 70-80% RH) for periods of fumigation that are otherwise efficacious at 24 °C/ 75% RH.

Modelling of deformation of underground tunnel lining, interacting with water-saturated soil

NASA Astrophysics Data System (ADS)

Berezhnoi, D. V.; Balafendieva, I. S.; Sachenkov, A. A.; Sekaeva, L. R.

2016-11-01

Built finite element method of calculating the deformation of underground tunnel lining, interacting with dry and water-saturated soils. To simulate the interaction between the lining and soils environments, including physical and non-linear, a special "contact" finite element, which allows to consider all cases of interaction between the contacting surfaces. It solved a number of problems of deformation with the ground subway tunnel lining rings.

Strength Analysis and Process Simulation of Subway Contact Rail Support Bracket of Composite Materials

NASA Astrophysics Data System (ADS)

Fedulov, Boris N.; Safonov, Alexander A.; Sergeichev, Ivan V.; Ushakov, Andrey E.; Klenin, Yuri G.; Makarenko, Irina V.

2016-10-01

An application of composites for construction of subway brackets is a very effective approach to extend their lifetime. However, this approach involves the necessity to prevent process-induced distortions of the bracket due to thermal deformation and chemical shrinkage. At present study, a process simulation has been carried out to support the design of the production tooling. The simulation was based on the application of viscoelastic model for the resin. Simulation results were verified by comparison with results of manufacturing experiments. To optimize the bracket structure the strength analysis was carried out as well.

Transmission characteristics of Bessel-Gaussian vortex beams propagating along both longitudinal and transverse directions in a subway tunnel

NASA Astrophysics Data System (ADS)

Wang, Xiaohui; Song, Yingxiong

2018-02-01

By exploiting the non-Kolmogorov model and Rytov approximation theory, a propagation model of Bessel-Gaussian vortex beams (BGVB) propagating in a subway tunnel is derived. Based on the propagation model, a model of orbital angular momentum (OAM) mode probability distribution is established to evaluate the propagation performance when the beam propagates along both longitudinal and transverse directions in the subway tunnel. By numerical simulations and experimental verifications, the influences of the various parameters of BGVB and turbulence on the OAM mode probability distribution are evaluated, and the results of simulations are consistent with the experimental statistics. The results verify that the middle area of turbulence is more beneficial for the vortex beam propagation than the edge; when the BGVB propagates along the longitudinal direction in the subway tunnel, the effects of turbulence on the OAM mode probability distribution can be decreased by selecting a larger anisotropy parameter, smaller coherence length, larger non-Kolmogorov power spectrum coefficient, smaller topological charge number, deeper subway tunnel, lower train speed, and longer wavelength. When the BGVB propagates along the transverse direction, the influences can be also mitigated by adopting a larger topological charge number, less non-Kolmogorov power spectrum coefficient, smaller refractive structure index, shorter wavelength, and shorter propagation distance.

Bioaerosols in the Barcelona subway system.

PubMed

Triadó-Margarit, X; Veillette, M; Duchaine, C; Talbot, M; Amato, F; Minguillón, M C; Martins, V; de Miguel, E; Casamayor, E O; Moreno, T

2017-05-01

Subway systems worldwide transport more than 100 million people daily; therefore, air quality on station platforms and inside trains is an important urban air pollution issue. We examined the microbiological composition and abundance in space and time of bioaerosols collected in the Barcelona subway system during a cold period. Quantitative PCR was used to quantify total bacteria, Aspergillus fumigatus, influenza A and B, and rhinoviruses. Multitag 454 pyrosequencing of the 16S rRNA gene was used to assess bacterial community composition and biodiversity. The results showed low bioaerosol concentrations regarding the targeted microorganisms, although the bacterial bioburden was rather high (10 4 bacteria/m 3 ). Airborne bacterial communities presented a high degree of overlap among the different subway environments sampled (inside trains, platforms, and lobbies) and were dominated by a few widespread taxa, with Methylobacterium being the most abundant genus. Human-related microbiota in sequence dataset and ascribed to potentially pathogenic bacteria were found in low proportion (maximum values below 2% of sequence readings) and evenly detected. Hence, no important biological exposure marker was detected in any of the sampled environments. Overall, we found that commuters are not the main source of bioaerosols in the Barcelona subway system. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Web Information Systems for Monitoring and Control of Indoor Air Quality at Subway Stations

NASA Astrophysics Data System (ADS)

Choi, Gi Heung; Choi, Gi Sang; Jang, Joo Hyoung

In crowded subway stations indoor air quality (IAQ) is a key factor for ensuring the safety, health and comfort of passengers. In this study, a framework for web-based information system in VDN environment for monitoring and control of IAQ in subway stations is suggested. Since physical variables that describing IAQ need to be closely monitored and controlled in multiple locations in subway stations, concept of distributed monitoring and control network using wireless media needs to be implemented. Connecting remote wireless sensor network and device (LonWorks) networks to the IP network based on the concept of VDN can provide a powerful, integrated, distributed monitoring and control performance, making a web-based information system possible.

Analysis and Countermeasure Study on DC Bias of Main Transformer in a City

NASA Astrophysics Data System (ADS)

Wang, PengChao; Wang, Hongtao; Song, Xinpu; Gu, Jun; Liu, yong; Wu, weili

2017-07-01

According to the December 2015 Guohua Beijing thermal power transformer DC magnetic bias phenomenon, the monitoring data of 24 hours of direct current is analyzed. We find that the maximum DC current is up to 25 and is about 30s for the trend cycle, on this basis, then, of the geomagnetic storm HVDC and subway operation causes comparison of the mechanism, and make a comprehensive analysis of the thermal power plant’s geographical location, surrounding environment and electrical contact etc.. The results show that the main reason for the DC bias of Guohua thermal power transformer is the operation of the subway, and the change of the DC bias current is periodic. Finally, of Guohua thermal power transformer DC magnetic bias control method is studied, the simulation results show that the method of using neutral point with small resistance or capacitance can effectively inhibit the main transformer neutral point current.

Temporal variability of the bioaerosol background at a subway station: concentration level, size distribution, and diversity of airborne bacteria.

PubMed

Dybwad, Marius; Skogan, Gunnar; Blatny, Janet Martha

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10(3) CFU m(-3) and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

Temporal Variability of the Bioaerosol Background at a Subway Station: Concentration Level, Size Distribution, and Diversity of Airborne Bacteria

PubMed Central

Dybwad, Marius; Skogan, Gunnar

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 103 CFU m−3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents. PMID:24162566

Formation and alteration of airborne particles in the subway environment.

PubMed

Moreno, T; Querol, X; Martins, V; Minguillón, M C; Reche, C; Ku, L H; Eun, H R; Ahn, K H; Capdevila, M; de Miguel, E

2017-01-25

Most particles in the rail subway environment are sub-micron sized ferruginous flakes and splinters generated mechanically by frictional wear of brake pads, wheels and rails. To better understand the mechanisms of formation and the alteration processes affecting inhalable particles in subways, PM samples (1-2.5 μm and 2.5-10 μm) were collected in the Barcelona Metro and then studied under a scanning electron microscope. Most particles in these samples are hematitic (up to 88%), with relatively minor amounts of mineral matter (up to 9%) and sulphates (up to 5%). Detailed microscopy (using back scattered and TEM-DRX imaging) reveals how many of the metallic particles comprise the metallic Fe nucleus surrounded by hematite (Fe 2 O 3 ) and a coating of sulphate and chloride salts mixed with mineral matter (including Ca-carbonates, clay minerals and quartz). These observations record the emission of fine to ultrafine FePM by frictional wear at elevated temperatures that promote rapid partial (or complete) oxidation of the native metal. Water condensing on the PM surface during cooling leads to the adsorption of inorganic mineral particles that coat the iron oxide. The distinctively layered polymineralic structure that results from these processes is peculiar to particles generated in the subway environment and very different from PM typically inhaled outdoors.

Granulometric and magnetic properties of deposited particles in the Beijing subway and the implications for air quality management.

PubMed

Cui, Guipeng; Zhou, Liping; Dearing, John

2016-10-15

The subway system is an important traffic facility in Beijing and its internal air quality is an environmental issue that could potentially affect millions of people every day. Due to the intrinsic nature of rail abrasion in subway tunnels, iron-containing particles can be generated and become suspended in the subway environment. While some studies (e.g. Li et al., 2006) have monitored the in-train levels of PM2.5 (particles<2.5μm), there is a lack of systematic assessment of the concentration and characteristics of iron-containing particles in the Beijing subway system. Here we report results of a study on the granulometric and magnetic properties of deposited particle samples collected at different localities of the Beijing subway system. Our results show that the subway samples are characterized by the presence of fine particles. Volume proportions of 6.1±1.3% for particles<2.5μm and 27.5±6.1% for particles<10μm are found in the bulk subway samples. These samples exhibit a strong magnetic signal, which is approximately two orders of magnitude higher than that in naturally deposited particles collected in Beijing. Fine grained ferromagnetic and ferrimagnetic minerals (e.g. iron and magnetite, respectively) are identified from mineral magnetic measurements and scanning electric microscopy. The samples collected from the Beijing stations with platform screen doors are found to be magnetically stronger and finer than those without them, suggesting that platform screen doors have failed to block the fine iron-containing particles released from the rail tunnel. Given the potential health consequences of fine suspended iron-containing particles, our results have important implications for air quality management in the Beijing subway system. Copyright © 2016 Elsevier B.V. All rights reserved.

Music as Transitional Object and Practice: Children's Spontaneous Musical Behaviors in the Subway

ERIC Educational Resources Information Center

Custodero, Lori A.; Calì, Claudia; Diaz-Donoso, Adriana

2016-01-01

This study looks at children's music making in a public setting designed for society writ large. Although known to most children in the city, the subway presents a unique environment, both structurally predictable yet sonically dynamic; it is in continuous transition. Adopting Winnicott's psychoanalytical perspective, we make a case for viewing…

Chemical compositions of subway particles in Seoul, Korea determined by a quantitative single particle analysis.

PubMed

Kang, Sunni; Hwang, HeeJin; Park, YooMyung; Kim, HyeKyoung; Ro, Chul-Un

2008-12-15

A novel single particle analytical technique, low-Z particle electron probe X-ray microanalysis, was applied to characterize seasonal subway samples collected at a subway station in Seoul, Korea. For all 8 samples collected twice in each season, 4 major types of subway particles, based on their chemical compositions, are significantly encountered: Fe-containing; soil-derived; carbonaceous; and secondary nitrate and/or sulfate particles. Fe-containing particles are generated indoors from wear processes at rail-wheel-brake interfaces while the others may be introduced mostly from the outdoor urban atmosphere. Fe-containing particles are the most frequently encountered with relative abundances in the range of 61-79%. In this study, it is shown that Fe-containing subway particles almost always exist either as partially or fully oxidized forms in underground subway microenvironments. Their relative abundances of Fe-containing particles increase as particle sizes decrease. Relative abundances of Fe-containing particles are higher in morning samples than in afternoon samples because of heavier train traffic in the morning. In the summertime samples, Fe-containing particles are the most abundantly encountered, whereas soil-derived and nitrate/sulfate particles are the least encountered, indicating the air-exchange between indoor and outdoor environments is limited in the summer, owing to the air-conditioning in the subway system. In our work, it was observed that the relative abundances of the particles of outdoor origin vary somewhat among seasonal samples to a lesser degree, reflecting that indoor emission sources predominate.

Characterization of airborne bacteria at an underground subway station.

PubMed

Dybwad, Marius; Granum, Per Einar; Bruheim, Per; Blatny, Janet Martha

2012-03-01

The reliable detection of airborne biological threat agents depends on several factors, including the performance criteria of the detector and its operational environment. One step in improving the detector's performance is to increase our knowledge of the biological aerosol background in potential operational environments. Subway stations are enclosed public environments, which may be regarded as potential targets for incidents involving biological threat agents. In this study, the airborne bacterial community at a subway station in Norway was characterized (concentration level, diversity, and virulence- and survival-associated properties). In addition, a SASS 3100 high-volume air sampler and a matrix-assisted laser desorption ionization-time of flight mass spectrometry-based isolate screening procedure was used for these studies. The daytime level of airborne bacteria at the station was higher than the nighttime and outdoor levels, and the relative bacterial spore number was higher in outdoor air than at the station. The bacterial content, particle concentration, and size distribution were stable within each environment throughout the study (May to September 2010). The majority of the airborne bacteria belonged to the genera Bacillus, Micrococcus, and Staphylococcus, but a total of 37 different genera were identified in the air. These results suggest that anthropogenic sources are major contributors to airborne bacteria at subway stations and that such airborne communities could harbor virulence- and survival-associated properties of potential relevance for biological detection and surveillance, as well as for public health. Our findings also contribute to the development of realistic testing and evaluation schemes for biological detection/surveillance systems by providing information that can be used to mimic real-life operational airborne environments in controlled aerosol test chambers.

Characterization of Airborne Bacteria at an Underground Subway Station

PubMed Central

Dybwad, Marius; Granum, Per Einar; Bruheim, Per

2012-01-01

The reliable detection of airborne biological threat agents depends on several factors, including the performance criteria of the detector and its operational environment. One step in improving the detector's performance is to increase our knowledge of the biological aerosol background in potential operational environments. Subway stations are enclosed public environments, which may be regarded as potential targets for incidents involving biological threat agents. In this study, the airborne bacterial community at a subway station in Norway was characterized (concentration level, diversity, and virulence- and survival-associated properties). In addition, a SASS 3100 high-volume air sampler and a matrix-assisted laser desorption ionization–time of flight mass spectrometry-based isolate screening procedure was used for these studies. The daytime level of airborne bacteria at the station was higher than the nighttime and outdoor levels, and the relative bacterial spore number was higher in outdoor air than at the station. The bacterial content, particle concentration, and size distribution were stable within each environment throughout the study (May to September 2010). The majority of the airborne bacteria belonged to the genera Bacillus, Micrococcus, and Staphylococcus, but a total of 37 different genera were identified in the air. These results suggest that anthropogenic sources are major contributors to airborne bacteria at subway stations and that such airborne communities could harbor virulence- and survival-associated properties of potential relevance for biological detection and surveillance, as well as for public health. Our findings also contribute to the development of realistic testing and evaluation schemes for biological detection/surveillance systems by providing information that can be used to mimic real-life operational airborne environments in controlled aerosol test chambers. PMID:22247150

Embedding human annoyance rate models in wireless smart sensors for assessing the influence of subway train-induced ambient vibration

NASA Astrophysics Data System (ADS)

Sun, Ke; Zhang, Wei; Ding, Huaping; Kim, Robin E.; Spencer, Billie F., Jr.

2016-10-01

The operation of subway trains induces ambient vibrations, which may cause annoyance and other adverse effects on humans, eventually leading to physical, physiological, and psychological problems. In this paper, the human annoyance rate (HAR) models, used to assess the human comfort under the subway train-induced ambient vibrations, were deduced and the calibration curves for 5 typical use circumstances were addressed. An autonomous measurement system, based on the Imote2, wireless smart sensor (WSS) platform, plus the SHM-H, high-sensitivity accelerometer board, was developed for the HAR assessment. The calibration curves were digitized and embedded in the computational core of the WSS unit. Experimental validation was conducted, using the developed system on a large underground reinforced concrete frame structure adjoining the subway station. The ambient acceleration of both basement floors was measured; the embedded computation was implemented and the HAR assessment results were wirelessly transmitted to the central server, all by the WSS unit. The HAR distributions of the testing areas were identified, and the extent to which both basements will be influenced by the close-up subway-train’s operation, in term of the 5 typical use circumstances, were quantitatively assessed. The potential of the WSS-based autonomous system for the fast environment impact assessment of the subway train-induced ambient vibration was well demonstrated.

Steel dust in the New York City subway system as a source of manganese, chromium, and iron exposures for transit workers.

PubMed

Chillrud, Steven N; Grass, David; Ross, James M; Coulibaly, Drissa; Slavkovich, Vesna; Epstein, David; Sax, Sonja N; Pederson, Dee; Johnson, David; Spengler, John D; Kinney, Patrick L; Simpson, H James; Brandt-Rauf, Paul

2005-03-01

The United States Clean Air Act Amendments of 1990 reflected increasing concern about potential effects of low-level airborne metal exposure on a wide array of illnesses. Here we summarize results demonstrating that the New York City (NYC) subway system provides an important microenvironment for metal exposures for NYC commuters and subway workers and also describe an ongoing pilot study of NYC transit workers' exposure to steel dust. Results from the TEACH (Toxic Exposure Assessment, a Columbia and Harvard) study in 1999 of 41 high-school students strongly suggest that elevated levels of iron, manganese, and chromium in personal air samples were due to exposure to steel dust in the NYC subway. Airborne concentrations of these three metals associated with fine particulate matter were observed to be more than 100 times greater in the subway environment than in home indoor or outdoor settings in NYC. While there are currently no known health effects at the airborne levels observed in the subway system, the primary aim of the ongoing pilot study is to ascertain whether the levels of these metals in the subway air affect concentrations of these metals or related metabolites in the blood or urine of exposed transit workers, who due to their job activities could plausibly have appreciably higher exposures than typical commuters. The study design involves recruitment of 40 transit workers representing a large range in expected exposures to steel dust, the collection of personal air samples of fine particulate matter, and the collection of blood and urine samples from each monitored transit worker.

Culture-Independent Analysis of Aerosol Microbiology in a Metropolitan Subway System

PubMed Central

Robertson, Charles E.; Baumgartner, Laura K.; Harris, J. Kirk; Peterson, Kristen L.; Stevens, Mark J.; Frank, Daniel N.

2013-01-01

The goal of this study was to determine the composition and diversity of microorganisms associated with bioaerosols in a heavily trafficked metropolitan subway environment. We collected bioaerosols by fluid impingement on several New York City subway platforms and associated sites in three sampling sessions over a 1.5-year period. The types and quantities of aerosolized microorganisms were determined by culture-independent phylogenetic analysis of small-subunit rRNA gene sequences by using both Sanger (universal) and pyrosequencing (bacterial) technologies. Overall, the subway bacterial composition was relatively simple; only 26 taxonomic families made up ∼75% of the sequences determined. The microbiology was more or less similar throughout the system and with time and was most similar to outdoor air, consistent with highly efficient air mixing in the system. Identifiable bacterial sequences indicated that the subway aerosol assemblage was composed of a mixture of genera and species characteristic of soil, environmental water, and human skin commensal bacteria. Eukaryotic diversity was mainly fungal, dominated by organisms of types associated with wood rot. Human skin bacterial species (at 99% rRNA sequence identity) included the Staphylococcus spp. Staphylococcus epidermidis (the most abundant and prevalent commensal of the human integument), S. hominis, S. cohnii, S. caprae, and S. haemolyticus, all well-documented human commensal bacteria. We encountered no organisms of public health concern. This study is the most extensive culture-independent survey of subway microbiota so far and puts in place pre-event information required for any bioterrorism surveillance activities or monitoring of the microbiological impact of recent subway flooding events. PMID:23542619

Culture-independent analysis of aerosol microbiology in a metropolitan subway system.

PubMed

Robertson, Charles E; Baumgartner, Laura K; Harris, J Kirk; Peterson, Kristen L; Stevens, Mark J; Frank, Daniel N; Pace, Norman R

2013-06-01

The goal of this study was to determine the composition and diversity of microorganisms associated with bioaerosols in a heavily trafficked metropolitan subway environment. We collected bioaerosols by fluid impingement on several New York City subway platforms and associated sites in three sampling sessions over a 1.5-year period. The types and quantities of aerosolized microorganisms were determined by culture-independent phylogenetic analysis of small-subunit rRNA gene sequences by using both Sanger (universal) and pyrosequencing (bacterial) technologies. Overall, the subway bacterial composition was relatively simple; only 26 taxonomic families made up ~75% of the sequences determined. The microbiology was more or less similar throughout the system and with time and was most similar to outdoor air, consistent with highly efficient air mixing in the system. Identifiable bacterial sequences indicated that the subway aerosol assemblage was composed of a mixture of genera and species characteristic of soil, environmental water, and human skin commensal bacteria. Eukaryotic diversity was mainly fungal, dominated by organisms of types associated with wood rot. Human skin bacterial species (at 99% rRNA sequence identity) included the Staphylococcus spp. Staphylococcus epidermidis (the most abundant and prevalent commensal of the human integument), S. hominis, S. cohnii, S. caprae, and S. haemolyticus, all well-documented human commensal bacteria. We encountered no organisms of public health concern. This study is the most extensive culture-independent survey of subway microbiota so far and puts in place pre-event information required for any bioterrorism surveillance activities or monitoring of the microbiological impact of recent subway flooding events.

Pedestrian evacuation at the subway station under fire

NASA Astrophysics Data System (ADS)

Xiao-Xia, Yang; Hai-Rong, Dong; Xiu-Ming, Yao; Xu-Bin, Sun

2016-04-01

With the development of urban rail transit, ensuring the safe evacuation of pedestrians at subway stations has become an important issue in the case of an emergency such as a fire. This paper chooses the platform of line 4 at the Beijing Xuanwumen subway station to study the emergency evacuation process under fire. Based on the established platform, effects of the fire dynamics, different initial pedestrian densities, and positions of fire on evacuation are investigated. According to simulation results, it is found that the fire increases the air temperature and the smoke density, and decreases pedestrians’ visibility and walking velocity. Also, there is a critical initial density at the platform if achieving a safe evacuation within the required 6 minutes. Furthermore, different positions of fire set in this paper have little difference on crowd evacuation if the fire is not large enough. The suggestions provided in this paper are helpful for the subway operators to prevent major casualties. Project supported by the National Natural Science Foundation of China (Grant Nos. 61322307 and 61233001).

Key techniques and risk management for the application of the Pile-Beam-Arch (PBA) excavation method: a case study of the Zhongjie subway station.

PubMed

Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

2014-01-01

The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area.

Factors associated with suicide ideation among subway drivers in Korea.

PubMed

Byun, Junsu; Kim, Hyoung-Ryoul; Lee, Hye-Eun; Kim, Se-Eun; Lee, Jongin

2016-01-01

There were several suicide events of subway drivers in Korea. The aim of this study is to explore work-related factors associated with suicide ideation among subway drivers. We analyzed data from 980 male subway drivers. A section of the Korean version of the Composite International Diagnostic Interview (K-CIDI 2.1) was administered by trained interviewers to judge whether a driver has suicide ideation and to diagnose psychiatric disorders. A questionnaire was also administered to collect data on sociodemographic characteristics, work environments, occupational stress, person under train (PUT) experience, and work-related problems. Occupational stress was examined by using the Korean Occupational Stress Scale (KOSS). Logistic regression was applied to evaluate the association between work-related factors and suicide ideation among subway drivers. Regarding work-related problems, conflict with passengers and sudden stops due to the emergency bell were significantly associated with suicide ideation. MDD, PTSD, and panic disorder were strongly associated with suicide ideation. In the analysis of occupational stress, insufficient job control (OR 2.34) and lack of reward (OR 2.52) were associated with suicide ideation even after being adjusted for psychiatric disorders and other work-related factors. Insufficient job control and lack of reward were associated with suicide ideation among subway drivers. Strategies for drivers to have autonomy while working and to achieve effort-reward balance should be implemented. Furthermore, drivers who have experienced negative work-related problems should be managed appropriately.

Manned Gaming and Simulation Relating to Terrorism and Weapons of Mass Destruction: A Review of the Literature

DTIC Science & Technology

2004-04-17

Israel’s Blood group and the 1995 use of sarin on the Tokyo subway by the Japanese Aum Shinrikyo cult. However, in the former case, the number of...Center Ft. Irwin, CA Civilian information: (760) 380-3369 http://www.irwin.army.mil/default.htm U.S. Army Red Franchise Organization TRADOC...examination of the 1995 Aum Shinrikyo sarin attack in the Tokyo subway system. From there, Ataxia inventories the various federal response assets and

Application Analysis of BIM Technology in Metro Rail Transit

NASA Astrophysics Data System (ADS)

Liu, Bei; Sun, Xianbin

2018-03-01

With the rapid development of urban roads, especially the construction of subway rail transit, it is an effective way to alleviate urban traffic congestion. There are limited site space, complex resource allocation, tight schedule, underground pipeline complex engineering problems. BIM technology, three-dimensional visualization, parameterization, virtual simulation and many other advantages can effectively solve these technical problems. Based on the project of Shenzhen Metro Line 9, BIM technology is innovatively researched throughout the lifecycle of BIM technology in the context of the metro rail transit project rarely used at this stage. The model information file is imported into Navisworks for four-dimensional animation simulation to determine the optimum construction scheme of the shield machine. Subway construction management application platform based on BIM and private cloud technology, the use of cameras and sensors to achieve electronic integration, dynamic monitoring of the operation and maintenance of underground facilities. Make full use of the many advantages of BIM technology to improve the engineering quality and construction efficiency of the subway rail transit project and to complete the operation and maintenance.

Key Techniques and Risk Management for the Application of the Pile-Beam-Arch (PBA) Excavation Method: A Case Study of the Zhongjie Subway Station

PubMed Central

Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

2014-01-01

The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area. PMID:25221783

Temporal and spatial patterns of suicides in Stockholm's subway stations.

PubMed

Uittenbogaard, Adriaan; Ceccato, Vania

2015-08-01

This paper investigates the potential temporal and spatial variations of suicides in subway stations in Stockholm, Sweden. The study also assesses whether the variation in suicide rates is related to the station environments by controlling for each station's location and a number of contextual factors using regression models and geographical information systems (GIS). Data on accidents are used as references for the analysis of suicides. Findings show that suicides tend to occur during the day and in the spring. They are concentrated in the main transportation hubs but, interestingly, during off-peak hours. However, the highest rates of suicides per passenger are found in Stockholm's subway stations located in the Southern outskirts. More than half of the variation in suicide rates is associated with stations that have walls between the two sides of the platform but still allow some visibility from passers-by. The surrounding environment and socioeconomic context show little effect on suicide rates, but stations embedded in areas with high drug-related crime rates tend to show higher suicide rates. Copyright © 2015 Elsevier Ltd. All rights reserved.

Research on station management in subway operation safety

NASA Astrophysics Data System (ADS)

Li, Yiman

2017-10-01

The management of subway station is an important part of the safe operation of urban subway. In order to ensure the safety of subway operation, it is necessary to study the relevant factors that affect station management. In the protection of subway safety operations on the basis of improving the quality of service, to promote the sustained and healthy development of subway stations. This paper discusses the influencing factors of subway operation accident and station management, and analyzes the specific contents of station management security for subway operation, and develops effective suppression measures. It is desirable to improve the operational quality and safety factor for subway operations.

Air pollution and activity during transportation by car, subway, and walking.

PubMed

Morabia, Alfredo; Amstislavski, Philippe N; Mirer, Franklin E; Amstislavski, Tashia M; Eisl, Holger; Wolff, Mary S; Markowitz, Steven B

2009-07-01

Little evidence exists about the health risks and benefits associated with using public buses and subways rather than cars. The objective of the current study was to assess the magnitude and variance of personal exposure to particulate matter 2.5 microns or smaller (PM(2.5)) and concomitant physical activity energy expenditure (PAEE) for transportation by car, subway, or walking. Twenty nonsmoking volunteers from New York City traveled on predetermined routes by car, subway, and walking, for up to 8 hours on 3 different days, between October 2007 and February 2008. Outfitted with a personal monitor with PM(2.5) aerosol inlet, and a GPS receiver, they completed a detailed physical activity diary for each route. Both metabolic equivalent (MET) and PAEE rates (Kcal/min) were computed from GPS-derived activity durations and speeds, activity-specific METs, and measured body weight. Total PM(2.5) exposures did not differ among car, subway, and walking arms (respectively, 21.4, 30.6, and 26.5 microg/m(3) x min, p=0.19); but average MET values (respectively, 1.51, 2.03, and 2.60 Kcal/kg x hr, p<0.0001) and PAEE rates (1.74, 2.35, and 3.04 Kcal/min, p<0.0001) did. After correction for the humidity factor, exposure to PM(2.5) appeared to be lower for the car arm (13.1 microg/m(3) x min) than for the subway (19.6 microg/m(3) x min) or walking (23.9 microg/m(3) x min, p=0.004) arms. Driving cars was associated with less physical activity but not necessarily less exposure to PM(2.5) than riding subways or walking in an urban environment. These effect sizes and variances can be used to design larger experiments assessing the health effects of urban transportation.

Particle deposition onto people in a transit venue

DOE PAGES

Liljegren, James C.; Brown, David F.; Lunden, Melissa M.; ...

2016-07-11

Following the release of an aerosolized biological agent in a transit venue, material deposited on waiting passengers and subsequently shed from their clothing may significantly magnify the scope and consequences of such an attack. Published estimates of the relevant particle deposition and resuspension parameters for complex, real-world environments such as a transit facility are non-existent. In this study, measurements of particle deposition velocity onto cotton fabric samples affixed to stationary and walking persons in a large multimodal transit facility were obtained for tracer particle releases carried out as part of a larger study of subway airflows and particulate transport. Depositionmore » velocities onto cotton and wool were also obtained using a novel automated sampling mechanism deployed at locations in the transit facility and throughout the subway. The data revealed higher deposition velocities than have been previously reported for people exposed in test chambers or office environments. Furthermore, the relatively high rates of deposition onto people in a transit venue obtained in this study suggest it is possible that fomite transport by subway and commuter/regional rail passengers could present a significant mechanism for rapidly dispersing a biological agent throughout a metropolitan area and beyond.« less

Particle deposition onto people in a transit venue

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

Liljegren, James C.; Brown, David F.; Lunden, Melissa M.

Following the release of an aerosolized biological agent in a transit venue, material deposited on waiting passengers and subsequently shed from their clothing may significantly magnify the scope and consequences of such an attack. Published estimates of the relevant particle deposition and resuspension parameters for complex, real-world environments such as a transit facility are non-existent. In this study, measurements of particle deposition velocity onto cotton fabric samples affixed to stationary and walking persons in a large multimodal transit facility were obtained for tracer particle releases carried out as part of a larger study of subway airflows and particulate transport. Depositionmore » velocities onto cotton and wool were also obtained using a novel automated sampling mechanism deployed at locations in the transit facility and throughout the subway. The data revealed higher deposition velocities than have been previously reported for people exposed in test chambers or office environments. Furthermore, the relatively high rates of deposition onto people in a transit venue obtained in this study suggest it is possible that fomite transport by subway and commuter/regional rail passengers could present a significant mechanism for rapidly dispersing a biological agent throughout a metropolitan area and beyond.« less

Noise pollution survey of a two-storey intersection station in Tehran metropolitan subway system.

PubMed

Ghotbi, Mohammad Reza; Monazzam, Mohammad Reza; Baneshi, Mohammad Reza; Asadi, Mohammad; Fard, Samaneh Momen Bellah

2012-01-01

According to the world population increase and demand on transportation in mega cities, modern and low-cost technologies are remarkably considered. Meanwhile, subway system, as a means to transfer a large population of people, is extremely welcomed due to its particular advantages including time and cost savings, traffic jam avoidance, and unaffected by weather. Nevertheless, despite the benefits of these technologies, such devices also have been associated with disadvantages for human. In many subway systems, noisy environments are clearly observed; therefore, workers and even the passengers are exposed to higher noise levels than permissible limit. In this research, noise measurements were performed at Imam Khomeini Station as the most crowded intersection subway station in Tehran. In this descriptive-sectional survey, the amount of noise pollution was investigated at both stories of Imam Khomeini Intersection Station. A variety of noise pollution indicators such as L(eq) 10 min were separately measured at each storey through five measurement points from 7 A.M. to 10 P.M. It was shown that the equivalent sound level range at Imam Khomeini station towards Elmo Sanat and Imam Khomeini towards Mirdamad were between 70.56-79.54 and 68.35-79.12 dB (A), respectively. It was indicated that except for the entrance stairs to the subway waiting platform and the first section of the platform on both stories, other measurement stations have the same equivalent sound levels.

Characteristics and personal exposures of carbonyl compounds in the subway stations and in-subway trains of Shanghai, China.

PubMed

Feng, Yanli; Mu, Cuicui; Zhai, Jinqing; Li, Jian; Zou, Ting

2010-11-15

Carbonyl compounds including their concentrations, potential sources, diurnal variations and personal exposure were investigated in six subway stations and in-subway trains in Shanghai in June 2008. The carbonyls were collected onto solid sorbent (Tenax TA) coated with pentafluorophenyl hydrazine (PFPH), followed by solvent extraction and gas chromatography (GC)/mass spectrometry (MS) analysis of the PFPH derivatives. The total carbonyl concentrations of in-subway train were about 1.4-2.5 times lower than in-subway stations. A significant correlation (R>0.5, p<0.01) between the concentrations of the low molecular-weight carbonyl compounds (

A comparative assessment of PM2.5 exposures in light-rail, subway, freeway, and surface street environments in Los Angeles and estimated lung cancer risk.

PubMed

Kam, Winnie; Delfino, Ralph J; Schauer, James J; Sioutas, C

2013-01-01

According to the U.S. Census Bureau, 570000+ commuters in Los Angeles travel for over 60 minutes to work. Studies have shown that a substantial portion of particulate matter (PM) exposure can occur during this commute. This study represents the integration of the results from five commute environments in Los Angeles. Personal PM exposures are discussed for the: (1) METRO gold line, a ground-level light-rail route, (2) METRO red line, a subway line, (3) the 110, a high volume freeway with low heavy-duty vehicle (HDV) fraction, (4) the 710, a major corridor for HDVs from the Port of Los Angeles, and (5) Wilshire/Sunset Boulevards, major surface streets. Chemical analysis including total and water-soluble metals and trace elements, elemental and organic carbon (EC/OC), and polycyclic aromatic hydrocarbons (PAHs) was performed. The focus of this study is to compare the composition and estimated lung cancer risk of PM2.5 (dp < 2.5 μm) for the five differential commute environments. Metals associated with stainless steel, notably Fe, Cr, and Mn, were elevated for the red line (subway), most likely from abrasion processes between the rail and brakes; elements associated with tire and brake wear and oil additives (Ca, Ti, Sn, Sb, and Pb) were elevated on roadways. Elemental concentrations on the gold line (light-rail) were the lowest. For water-solubility, metals observed on the red line (subway) were the least soluble. PAHs are primarily derived from vehicular emissions. Overall, the 710 exhibited high levels of PAHs (3.0 ng m−3), most likely due to its high volume of HDVs, while the red and gold lines exhibited low PAH concentrations (0.6 and 0.8 ng m−3 for red and gold lines, respectively). Lastly, lung cancer risk due to inhalation of PAHs was calculated based on a commuter lifetime (45 years for 2 hours per workday). Results showed that lung cancer risk for the 710 is 3.8 and 4.5 times higher than the light-rail (gold line) and subway (red line), respectively. With low levels of both metal and PAH pollutants, our results indicate that commuting on the light-rail (gold line) may have potential health benefits when compared to driving on freeways and busy roadways.

Hydrochemistry of urban groundwater, Seoul, Korea: the impact of subway tunnels on groundwater quality.

PubMed

Chae, Gi-Tak; Yun, Seong-Taek; Choi, Byoung-Young; Yu, Soon-Young; Jo, Ho-Young; Mayer, Bernhard; Kim, Yun-Jong; Lee, Jin-Yong

2008-10-23

Hydrogeologic and hydrochemical data for subway tunnel seepage waters in Seoul (Republic of Korea) were examined to understand the effect of underground tunnels on the degradation of urban groundwater. A very large quantity of groundwater (up to 63 million m3 year(-1)) is discharged into subway tunnels with a total length of 287 km, resulting in a significant drop of the local groundwater table and the abandonment of groundwater wells. For the tunnel seepage water samples (n = 72) collected from 43 subway stations, at least one parameter among pathogenic microbes (total coliform, heterotrophic bacteria), dissolved Mn and Fe, NH4+, NO3(-), turbidity, and color exceeded the Korean Drinking Water Standards. Locally, tunnel seepage water was enriched in dissolved Mn (avg. 0.70 mg L(-1), max. 5.58 mg L(-1)), in addition to dissolved Fe, NH4+, and pathogenic microbes, likely due to significant inflow of sewage water from broken or leaking sewer pipes. Geochemical modeling of redox reactions was conducted to simulate the characteristic hydrochemistry of subway tunnel seepage. The results show that variations in the reducing conditions occur in urban groundwater, dependent upon the amount of organic matter-rich municipal sewage contaminating the aquifer. The organic matter facilitates the reduction and dissolution of Mn- and Fe-bearing solids in aquifers and/or tunnel construction materials, resulting in the successive increase of dissolved Mn and Fe. The present study clearly demonstrates that locally significant deterioration of urban groundwater is caused by a series of interlinked hydrogeologic and hydrochemical changes induced by underground tunnels.

Research on dynamic creep strain and settlement prediction under the subway vibration loading.

PubMed

Luo, Junhui; Miao, Linchang

2016-01-01

This research aims to explore the dynamic characteristics and settlement prediction of soft soil. Accordingly, the dynamic shear modulus formula considering the vibration frequency was utilized and the dynamic triaxial test conducted to verify the validity of the formula. Subsequently, the formula was applied to the dynamic creep strain function, with the factors influencing the improved dynamic creep strain curve of soft soil being analyzed. Meanwhile, the variation law of dynamic stress with sampling depth was obtained through the finite element simulation of subway foundation. Furthermore, the improved dynamic creep strain curve of soil layer was determined based on the dynamic stress. Thereafter, it could to estimate the long-term settlement under subway vibration loading by norms. The results revealed that the dynamic shear modulus formula is straightforward and practical in terms of its application to the vibration frequency. The values predicted using the improved dynamic creep strain formula closed to the experimental values, whilst the estimating settlement closed to the measured values obtained in the field test.

Evaluation of the air quality benefits of the subway system in São Paulo, Brazil.

PubMed

Silva, Cacilda Bastos Pereira da; Saldiva, Paulo Hilário Nascimento; Amato-Lourenço, Luis Fernando; Rodrigues-Silva, Fernando; Miraglia, Simone Georges El Khouri

2012-06-30

Air pollution is a severe problem in major urban areas due to increasing numbers of vehicles, reduced road capacity and few investments in public transportation, especially in developing countries. Public transportation has a special role in avoiding congestion and consequent environmental and health impacts but is considered expensive. The objective of this paper was to analyze the benefits of the São Paulo subway in terms of the air pollution in the city through strikes events, analyzing both the health outcomes and the related economic burden. For the strike events, increases in air pollutant concentrations during the strike day was observed when compared to a similar day in terms of day of the week and meteorological conditions. Increases in mortality were also observed and the associated economic burden calculated. Despite the elevated construction and operation costs of the subway, when environment and social values are considered, cost-benefit analysis results would indicate a worthwhile investment. The consideration of these aspects is essential to sustainable transportation analyses, and in the case of the São Paulo subway, our analysis clearly demonstrated the important role of this system in the city's environmental, social and economic attributes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Urban air quality comparison for bus, tram, subway and pedestrian commutes in Barcelona.

PubMed

Moreno, Teresa; Reche, Cristina; Rivas, Ioar; Cruz Minguillón, Maria; Martins, Vânia; Vargas, Concepción; Buonanno, Giorgio; Parga, Jesus; Pandolfi, Marco; Brines, Mariola; Ealo, Marina; Sofia Fonseca, Ana; Amato, Fulvio; Sosa, Garay; Capdevila, Marta; de Miguel, Eladio; Querol, Xavier; Gibbons, Wes

2015-10-01

Access to detailed comparisons in air quality variations encountered when commuting through a city offers the urban traveller more informed choice on how to minimise personal exposure to inhalable pollutants. In this study we report on an experiment designed to compare atmospheric contaminants inhaled during bus, subway train, tram and walking journeys through the city of Barcelona. Average number concentrations of particles 10-300 nm in size, N, are lowest in the commute using subway trains (N<2.5×10(4) part. cm(-3)), higher during tram travel and suburban walking (2.5×10(4) cm(-3)5.0×10(4) cm(-3)), with extreme transient peaks at busy traffic crossings commonly exceeding 1.0×10(5) cm(-3) and accompanied by peaks in Black Carbon and CO. Subway particles are coarser (mode 90 nm) than in buses, trams or outdoors (<70 nm), and concentrations of fine particulate matter (PM2.5) and Black Carbon are lower in the tram when compared to both bus and subway. CO2 levels in public transport reflect passenger numbers, more than tripling from outdoor levels to >1200 ppm in crowded buses and trains. There are also striking differences in inhalable particle chemistry depending on the route chosen, ranging from aluminosiliceous at roadsides and near pavement works, ferruginous with enhanced Mn, Co, Zn, Sr and Ba in the subway environment, and higher levels of Sb and Cu inside the bus. We graphically display such chemical variations using a ternary diagram to emphasise how "air quality" in the city involves a consideration of both physical and chemical parameters, and is not simply a question of measuring particle number or mass. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Identification of the sources of PM10 in a subway tunnel using positive matrix factorization.

PubMed

Park, Duckshin; Lee, Taejeong; Hwang, Doyeon; Jung, Wonseok; Lee, Yongil; Cho, KiChul; Kim, Dongsool; Lees, Kiyoung

2014-12-01

The level of particulate matter of less than 10 μm diameter (PM10) at subway platforms can be significantly reduced by installing a platform screen-door system. However, both workers and passengers might be exposed to higher PM10 levels while the cars are within the tunnel because it is a more confined environment. This study determined the PM10 levels in a subway tunnel, and identified the sources of PM10 using elemental analysis and receptor modeling. Forty-four PM10 samples were collected in the tunnel between the Gireum and Mia stations on Line 4 in metropolitan Seoul and analyzed using inductively coupled plasma-atomic emission spectrometry and ion chromatography. The major PM10 sources were identified using positive matrix factorization (PMF). The average PM10 concentration in the tunnels was 200.8 ± 22.0 μg/m3. Elemental analysis indicated that the PM10 consisted of 40.4% inorganic species, 9.1% anions, 4.9% cations, and 45.6% other materials. Iron was the most abundant element, with an average concentration of 72.5 ± 10.4 μg/m3. The PM10 sources characterized by PMF included rail, wheel, and brake wear (59.6%), soil combustion (17.0%), secondary aerosols (10.0%), electric cable wear (8.1%), and soil and road dust (5.4%). Internal sources comprising rail, wheel, brake, and electric cable wear made the greatest contribution to the PM10 (67.7%) in tunnel air. Implications: With installation of a platform screen door, PM10 levels in subway tunnels were higher than those on platforms. Tunnel PM10 levels exceeded 150 µg/m3 of the Korean standard for subway platform. Elemental analysis of PM10 in a tunnel showed that Fe was the most abundant element. Five PM10 sources in tunnel were identified by positive matrix factorization. Railroad-related sources contributed 68% of PM10 in the subway tunnel.

Assessment of the impact of dipped guideways on urban rail transit systems: Ventilation and safety requirements

NASA Technical Reports Server (NTRS)

1982-01-01

The ventilation and fire safety requirements for subway tunnels with dipped profiles between stations as compared to subway tunnels with level profiles were evaluated. This evaluation is based upon computer simulations of a train fire emergency condition. Each of the tunnel configurations evaluated was developed from characteristics that are representative of modern transit systems. The results of the study indicate that: (1) The level tunnel system required about 10% more station cooling than dipped tunnel systems in order to meet design requirements; and (2) The emergency ventilation requirements are greater with dipped tunnel systems than with level tunnel systems.

[WORKING CONDITIONS AND STATE OF HEALTH OF TBILISI SUBWAY EMPLOYEES].

PubMed

Khunashvili, N; Tsimakuridze, Mar; Bakradze, L; Khachapuridze, N; Tsimakuridze, Maya

2017-03-01

For the purpose of preventive events complex hygienic, clinical-functional, laboratory and biostatic researches are implemented on the basis of Tbilisi Subway. Conditions of work are characterized by complex of unfavorable factors of the working environment and the labor process. Working environment is characterized by combination of unfavorable state of physical factors and air pollution with dust and toxic substances. The levels of noise and vibration refer to the 3.4 class of harmfulness. The content of dust and toxic substances corresponds to 3.1-3.2 classes of working conditions harmfulness. In the indexes of health status, the leading diseases are pathology of cardiovascular, nervous and digestive systems. Cause-effect relationships between working conditions and individual health indicators have been already established, which served as the basis for the development of comprehensive preventive health measures.

Epidemiology of subway-related fatalities in New York City, 1990-2003.

PubMed

Gershon, Robyn R M; Pearson, Julie M; Nandi, Vijay; Vlahov, David; Bucciarelli-Prann, Angela; Tracy, Melissa; Tardiff, Kenneth; Galea, Sandro

2008-01-01

Subway transit is a relatively safe mode of transportation, yet compared to all other forms of mass transit in the United States (U.S.), subways have the highest fatality rate. The aim of this paper is to characterize subway-related fatalities in order to identify opportunities for risk reduction. Medical examiner records for all New York City (NYC) subway-related deaths (1990-2003) were reviewed. Data were abstracted on decedents' demographics and autopsy findings, including laboratory findings. There were 668 subway-related fatalities, of these, 10 (1.5%) were homicides, 343 (51.3%) were determined to be suicides, and 315 (47.2%) were accidental. Although decedent characteristics varied between fatality categories, they were not particularly informative with regard to prevention. Prevention strategies that focus on structural controls are likely to be most efficacious in improving the overall safety of the NYC subway systems. These findings suggest that structural rather than individual-level interventions would be most successful in preventing subway fatalities.

A usability assessment on a virtual reality system for panic disorder treatment

NASA Astrophysics Data System (ADS)

Lee, Jaelin; Kawai, Takashi; Yoshida, Nahoko; Izawa, Shuhei; Nomura, Shinobu; Eames, Douglas; Kaiya, Hisanobu

2008-02-01

The authors have developed a virtual reality exposure system that reflects the Japanese culture and environment. Concretely, the system focuses on the subway environment, which is the environment most patients receiving treatment for panic disorder at hospitals in Tokyo, Japan tend to avoid. The system is PC based and features realistic video images and highly interactive functionality. In particular, the system enables instant transformation of the virtual space and allows situations to be freely customized according to the condition and symptoms expressed by each patient. Positive results achieved in therapy assessments aimed at patients with panic disorder accompanying agoraphobia indicate the possibility of indoor treatment. Full utilization of the functionality available requires that the interactive functions be easily operable. Accordingly, there appears to be a need for usability testing aimed at determining whether or not a therapist can operate the system naturally while focusing fully on treatment. In this paper, the configuration of the virtual reality exposure system focusing on the subway environment is outlined. Further, the results of usability tests aimed at assessing how naturally it can be operated while focusing fully on treatment are described.

Incidence of lung cancer among subway drivers in Stockholm.

PubMed

Gustavsson, Per; Bigert, Carolina; Pollán, Marina

2008-07-01

Very high levels of airborne particles have been detected in the subway system in Stockholm. Subway particles are more toxic to DNA in cultured human lung cells than particles from ambient air. This cohort comprised all men in Stockholm County who were gainfully employed in 1970. They were followed for cancer incidence until 1989. Lung cancer cases were identified from the national cancer register. Subway drivers were identified from the census in 1970. The reference cohort comprised all transport and communication workers in Stockholm. There were nine cases of lung cancer among the subway drivers, giving a SIR of 0.82 (95% confidence interval 0.38-1.56). The lung cancer incidence was not increased among the subway drivers. The study gives some evidence against the hypothesis that subway particles would be more potent in inducing lung cancer than particles in ambient air. (c) 2008 Wiley-Liss, Inc.

Iron speciation of airborne subway particles by the combined use of energy dispersive electron probe X-ray microanalysis and Raman microspectrometry.

PubMed

Eom, Hyo-Jin; Jung, Hae-Jin; Sobanska, Sophie; Chung, Sang-Gwi; Son, Youn-Suk; Kim, Jo-Chun; Sunwoo, Young; Ro, Chul-Un

2013-11-05

Quantitative energy-dispersive electron probe X-ray microanalysis (ED-EPMA), known as low-Z particle EPMA, and Raman microspectrometry (RMS) were applied in combination for an analysis of the iron species in airborne PM10 particles collected in underground subway tunnels. Iron species have been reported to be a major chemical species in underground subway particles generated mainly from mechanical wear and friction processes. In particular, iron-containing particles in subway tunnels are expected to be generated with minimal outdoor influence on the particle composition. Because iron-containing particles have different toxicity and magnetic properties depending on their oxidation states, it is important to determine the iron species of underground subway particles in the context of both indoor public health and control measures. A recently developed analytical methodology, i.e., the combined use of low-Z particle EPMA and RMS, was used to identify the chemical species of the same individual subway particles on a single particle basis, and the bulk iron compositions of airborne subway particles were also analyzed by X-ray diffraction. The majority of airborne subway particles collected in the underground tunnels were found to be magnetite, hematite, and iron metal. All the particles collected in the tunnels of underground subway stations were attracted to permanent magnets due mainly to the almost ubiquitous ferrimagnetic magnetite, indicating that airborne subway particles can be removed using magnets as a control measure.

[Study on transition metals in airborne particulate matter in Shanghai city's subway].

PubMed

Bao, Liang-Man; Lei, Qian-Tao; Tan, Ming-Guang; Li, Xiao-Lin; Zhang, Gui-Lin; Liu, Wei; Li, Yan

2014-06-01

PM10 and PM2.5 aerosol particle samples were collected at a subway station in Shanghai and their morphology, chemical composition and transition metal species were studied. The mass concentrations of PM10 and PM2.5 inside the subway station were significantly higher than those measured in aboveground ambient air. The PM levels inside subway were much higher than the state control limit. The aerosol composition in the metro station was quite different from that of the aboveground urban particles. Concentrations of Fe, Mn and Cr were higher than the averages of aboveground urban air particles by factors of 8, 2, and 2, respectively, showing a substantial enrichment in subway. Scanning electron microscope (SEM) analysis showed that the subway particles had flat surfaces in combination with parallel scratches and sharp edges and looked like metal sheets or flakes. Furthermore, analysis of the atomic composition of typical subway particles by energy dispersive X-Ray (EDX) spectroscopy showed that oxygen and iron dominated the mass of the particles. The X-ray absorption near-edge structure (XANES) spectroscopy results showed that a fraction (> 26%) of the total iron in the PM10 was in the form of pure Fe, while in the street particles Fe(III) was shown to be a significant fraction of the total iron. The work demonstrated that the underground subway stations in Shanghai were an important microenvironment for exposure to transition metal aerosol for the people taking subway train for commuting every day and those who work in the subway stations, and the metal particle exposure for people in the subway station should not be ignored.

[Distribution of airborne fungi, particulate matter and carbon dioxide in Seoul metropolitan subway stations].

PubMed

Kim, Ki Youn; Park, Jae Beom; Kim, Chi Nyon; Lee, Kyung Jong

2006-07-01

The aims of this study were to examine the level of airborne fungi and environmental factors in Seoul metropolitan subway stations and to provide fundamental data to protect the health of subway workers and passengers. The field survey was performed from November in 2004 to February in 2005. A total 22 subway stations located at Seoul subway lines 1-4 were randomly selected. The measurement points were subway workers' activity areas (station office, bedroom, ticket office and driver's seat) and the passengers' activity areas (station precincts, inside train and platform). Air sampling for collecting airborne fungi was carried out using a one-stage cascade impactor. The PM and CO2 were measured using an electronic direct recorder and detecting tube, respectively. In the activity areas of the subway workers and passengers, the mean concentrations of airborne fungi were relatively higher in the workers' bedroom and station precinct whereas the concentration of particulate matter, PM10 and PM2.5, were relatively higher in the platform, inside the train and driver's seat than in the other activity areas. There was no significant difference in the concentration of airborne fungi between the underground and ground activity areas of the subway. The mean PM10 and PM2.5 concentration in the platform located at underground was significantly higher than that of the ground (p<0.05). The levels of airborne fungi in the Seoul subway line 1-4 were not serious enough to cause respiratory disease in subway workers and passengers. This indicates that there is little correlation between airborne fungi and particulate matter.

Random matrices and the New York City subway system

NASA Astrophysics Data System (ADS)

Jagannath, Aukosh; Trogdon, Thomas

2017-09-01

We analyze subway arrival times in the New York City subway system. We find regimes where the gaps between trains are well modeled by (unitarily invariant) random matrix statistics and Poisson statistics. The departure from random matrix statistics is captured by the value of the Coulomb potential along the subway route. This departure becomes more pronounced as trains make more stops.

Dynamics of subway networks based on vehicles operation timetable

NASA Astrophysics Data System (ADS)

Xiao, Xue-mei; Jia, Li-min; Wang, Yan-hui

2017-05-01

In this paper, a subway network is represented as a dynamic, directed and weighted graph, in which vertices represent subway stations and weights of edges represent the number of vehicles passing through the edges by considering vehicles operation timetable. Meanwhile the definitions of static and dynamic metrics which can represent vertices' and edges' local and global attributes are proposed. Based on the model and metrics, standard deviation is further introduced to study the dynamic properties (heterogeneity and vulnerability) of subway networks. Through a detailed analysis of the Beijing subway network, we conclude that with the existing network structure, the heterogeneity and vulnerability of the Beijing subway network varies over time when the vehicle operation timetable is taken into consideration, and the distribution of edge weights affects the performance of the network. In other words, although the vehicles operation timetable is restrained by the physical structure of the network, it determines the performances and properties of the Beijing subway network.

Airborne particulate metals in the New York City subway: A pilot study to assess the potential for health impacts✩,✩✩

PubMed Central

Grass, David S.; Ross, James M.; Family, Farnosh; Barbour, Jonathan; Simpson, H. James; Coulibaly, Drissa; Hernandez, Jennifer; Chen, Yingdi; Slavkovich, Vesna; Li, Yongliang; Graziano, Joseph; Santella, Regina M.; Brandt-Rauf, Paul; Chillrud, Steven N.

2011-01-01

A prior study in New York City observed that airborne concentrations of three metals found in steel – iron, manganese, and chromium – are more than 100 times higher in the subway system than in aboveground air. To investigate the potential for health effects of exposure at these levels, we conducted a pilot study of subway workers comparing personal exposures to steel dust with biomarkers of metal exposure, oxidative stress, and DNA damage in blood and urine samples. Workers wore a personal air sampler operating at 4 L/m for one to three work shifts with blood and urine samples collected at the end of the final shift. We found that PM2.5 exposures varied among subway workers on the basis of job title and job activity. The subway workers’ mean time-weighted PM2.5 exposure was 52 µg/m3, with a median of 27 µg/m3, and a range of 6–469 µg/m3. The observed concentrations of PM2.5, iron, manganese, and chromium fell well below occupational standards. Biomarker concentrations among the 39 subway workers were compared with a group of 11 bus drivers, and a group of 25 suburban office workers. Concentrations of DNA–protein crosslinks and chromium in plasma were significantly higher in subway workers than in bus drivers, but no significant difference was observed for these biomarkers between subway workers and office workers. Urinary isoprostane concentrations were significantly correlated with the number of years working in the subway system, and were detected at higher, though not significantly higher, concentrations in subway workers than in bus drivers or office workers. At the group level, there was no consistent pattern of biomarker concentrations among subway workers significantly exceeding those of the bus drivers and office workers. At the individual level, steel dust exposure was not correlated with any of the biomarkers measured. PMID:19926083

Airborne particulate metals in the New York City subway: a pilot study to assess the potential for health impacts.

PubMed

Grass, David S; Ross, James M; Family, Farnosh; Barbour, Jonathan; James Simpson, H; Coulibaly, Drissa; Hernandez, Jennifer; Chen, Yingdi; Slavkovich, Vesna; Li, Yongliang; Graziano, Joseph; Santella, Regina M; Brandt-Rauf, Paul; Chillrud, Steven N

2010-01-01

A prior study in New York City observed that airborne concentrations of three metals found in steel - iron, manganese, and chromium - are more than 100 times higher in the subway system than in aboveground air. To investigate the potential for health effects of exposure at these levels, we conducted a pilot study of subway workers comparing personal exposures to steel dust with biomarkers of metal exposure, oxidative stress, and DNA damage in blood and urine samples. Workers wore a personal air sampler operating at 4L/m for one to three work shifts with blood and urine samples collected at the end of the final shift. We found that PM(2.5) exposures varied among subway workers on the basis of job title and job activity. The subway workers' mean time-weighted PM(2.5) exposure was 52 microg/m3, with a median of 27 microg/m3, and a range of 6-469 microg/m3. The observed concentrations of PM(2.5), iron, manganese, and chromium fell well below occupational standards. Biomarker concentrations among the 39 subway workers were compared with a group of 11 bus drivers, and a group of 25 suburban office workers. Concentrations of DNA-protein crosslinks and chromium in plasma were significantly higher in subway workers than in bus drivers, but no significant difference was observed for these biomarkers between subway workers and office workers. Urinary isoprostane concentrations were significantly correlated with the number of years working in the subway system, and were detected at higher, though not significantly higher, concentrations in subway workers than in bus drivers or office workers. At the group level, there was no consistent pattern of biomarker concentrations among subway workers significantly exceeding those of the bus drivers and office workers. At the individual level, steel dust exposure was not correlated with any of the biomarkers measured.

Mechanisms related to the genotoxicity of particles in the subway and from other sources.

PubMed

Karlsson, Hanna L; Holgersson, Asa; Möller, Lennart

2008-03-01

Negative health effects of airborne particles have clearly been shown in epidemiological studies. People get exposed to particles from various sources such as the combustion of, for example, diesel and wood and also from particles arising from tire-road wear. Another source of importance for certain populations is exposure to particles in subway systems. We recently reported that these particles were more genotoxic when compared to that of several other particle types. The aim of this study was to further investigate and compare the toxicity of subway particles and particles from other sources as well as investigate some mechanisms behind the genotoxicity of subway particles. This was done by comparing the ability of subway particles and particles from a street, pure tire-road wear particles, and particles from wood and diesel combustion to cause mitochondrial depolarization and to form intracellular reactive oxygen species (ROS). Furthermore, the genotoxicity and ability to cause oxidative stress was compared to magnetite particles since this is a main component in subway particles. It was concluded that the subway particles and also street particles and particles from wood and diesel combustion caused mitochondrial depolarization. The ability to damage the mitochondria is thus not the only explanation for the high genotoxicity of subway particles. Subway particles also formed intracellular ROS. This effect may be part of the explanation as to why subway particles show such high genotoxicity when compared to that of other particles. Genotoxicity can, however, not be explained by the main component, magnetite, by water-soluble metals, or by intracellular mobilized iron. The genotoxicity is most likely caused by highly reactive surfaces giving rise to oxidative stress.

Subway emergency preparedness in Shanghai: A focused group and interview study exploring the perceived experiences of senior citizens and the disabled.

PubMed

Baffoe, Benjamin Ohene Kwapong; Shiyuan, Zheng

As Shanghai's population increases and currently being boosted by an influx of foreigners, there has been pressure on the subway system and this has led to a great concern for the aged and disabled people (including foreigners) who use the subway during emergency situations. The present study uses an exploratory research approach including a focus group discussion (FGD) and interviews to uncover the experiences, safety concerns, and challenges that the aged and disabled faces when using the subway. A total of 38 participants were involved in the study, which comprises of three FGDs and interviews conducted in the city of Shanghai. The findings reveal that most aged and disabled subway riders have little or no knowledge about emergency safety measures or safety symbols, the administering of first aid and have language barrier concerns. This study recommends that policy makers and sub-way operators should get the aged and disabled people involved in developing more educational programs that will help them to better the concept of safety prevention measures and it also suggests holding more emergency drills involving the aged and disabled. Braille language symbols, sign languages on TV screens, specially designed sub-way maps, low-frequency alarms with flashing lights, and information printed in multiple international languages should also be provided to help foreigners understand the instructions and information in the subways. Additionally, these measures could help all commuters to feel safer when using the subway.

Myocardial infarction in Swedish subway drivers.

PubMed

Bigert, Carolina; Klerdal, Kristina; Hammar, Niklas; Gustavsson, Per

2007-08-01

Particulate matter in urban air is associated with the risk of myocardial infarction in the general population. Very high levels of airborne particles have been detected in the subway system of Stockholm, as well as in several other large cities. This situation has caused concern for negative health effects among subway staff. The aim of this study was to investigate whether there is an increased incidence of myocardial infarction among subway drivers. Data from a population-based case-control study of men aged 40-69 in Stockholm County in 1976-1996 were used. The study included all first events of myocardial infarction in registers of hospital discharges and deaths. The controls were selected randomly from the general population. National censuses were used for information on occupation. Altogether, 22 311 cases and 131 496 controls were included. Among these, 54 cases and 250 controls had worked as subway drivers. The relative risk of myocardial infarction among subway drivers was not increased. It was 0.92 [95% confidence interval (95% CI) 0.68-1.25] when the subway drivers were compared with other manual workers and 1.06 (95% CI 0.78-1.43) when the subway drivers were compared with all other gainfully employed men. Subgroup analyses indicated no influence on the risk of myocardial infarction from the duration of employment, latency time, or time since employment stopped. Subway drivers in Stockholm do not have a higher incidence of myocardial infarction than other employed persons.

Spatial distribution of particulate matter (PM10 and PM2.5) in Seoul Metropolitan Subway stations.

PubMed

Kim, Ki Youn; Kim, Yoon Shin; Roh, Young Man; Lee, Cheol Min; Kim, Chi Nyon

2008-06-15

The aims of this study are to examine the concentrations of PM10 and PM2.5 in areas within the Seoul Metropolitan Subway network and to provide fundamental data in order to protect respiratory health of subway workers and passengers from air pollutants. A total of 22 subway stations located on lines 1-4 were selected based on subway official's guidance. At these stations both subway worker areas (station offices, rest areas, ticket offices and driver compartments) and passengers areas (station precincts, subway carriages and platforms) were the sites used for measuring the levels of PM. The mean concentrations of PM10 and PM2.5 were relatively higher on platforms, inside subway carriages and in driver compartments than in the other areas monitored. The levels of PM10 and PM2.5 for station precincts and platforms exceeded the 24-h acceptable threshold limits of 150 microg/m3 for PM10 and 35 microg/m3 for PM2.5, which are regulated by the U.S. Environmental Protection Agency (EPA). However, levels measured in station and ticket offices fell below the respective threshold. The mean PM10 and PM2.5 concentrations on platforms located underground were significantly higher than those at ground level (p<0.05).

Decontamination of Subway Railcar and Related Materials ...

EPA Pesticide Factsheets

Report In the event of a biological incident in a transportation hub such as a subway system, effective remediation of railcars, subway tunnels and stations will require the use of various decontamination approaches. One potential decontamination tool that could be used in such an event is the fogging of sporicidal liquids. The study described in this report builds on previous fogging decontamination research, but with a focus on decontaminating subway railcars and related materials.

Research on the analytical method about influence of gas leakage and explosion on subway

NASA Astrophysics Data System (ADS)

Ji, Wendong; Yang, Ligong; Chen, Lin

2018-05-01

With the construction and development of city subway, the cross impact of underground rail transit and gas pipe network is becoming more and more serious, but there is no analytical method for the impact of gas explosions on the subway. According to this paper, the gas leakage is equivalent to the TNT explosion equivalent, based on which, the calculation of the explosive impact load is carried out. On the basis of the concrete manifestation of gas explosion, it is more convenient to carry out the subsequent calculation by equivalently treating the explosive impact load as a uniform load within a certain range. The overlying soil of the subway station has played a protective role for the subway, making the displacement of the subway structure in the explosion process significantly reduced. The analysis on the actual case shows that this method can be successfully applied to the quantitative analysis of such accidents.

Reducing the impact of speed dispersion on subway corridor flow.

PubMed

Qiao, Jing; Sun, Lishan; Liu, Xiaoming; Rong, Jian

2017-11-01

The rapid increase in the volume of subway passengers in Beijing has necessitated higher requirements for the safety and efficiency of subway corridors. Speed dispersion is an important factor that affects safety and efficiency. This paper aims to analyze the management control methods for reducing pedestrian speed dispersion in subways. The characteristics of the speed dispersion of pedestrian flow were analyzed according to field videos. The control measurements which were conducted by placing traffic signs, yellow marking, and guardrail were proposed to alleviate speed dispersion. The results showed that the methods of placing traffic signs, yellow marking, and a guardrail improved safety and efficiency for all four volumes of pedestrian traffic flow, and the best-performing control measurement was guardrails. Furthermore, guardrails' optimal position and design measurements were explored. The research findings provide a rationale for subway managers in optimizing pedestrian traffic flow in subway corridors. Copyright © 2017. Published by Elsevier Ltd.

The effectiveness of platform screen doors for the prevention of subway suicides in South Korea.

PubMed

Chung, Yong Woon; Kang, Sung Jin; Matsubayashi, Tetsuya; Sawada, Yasuyuki; Ueda, Michiko

2016-04-01

Subway suicide can significantly impact the general public. Platform Screen Doors (PSDs) are considered to be an effective strategy to prevent suicides at subway stations, but the evidence on their effectiveness is limited. We assessed the effectiveness of installing half- and full-height platform screen doors in reducing subway suicides using Poisson regression analysis. Ten-year monthly panel data for 121 subway stations between 2003 and 2012 in the Seoul metropolitan area were used for the analysis. We found that installing PSDs decreases fatal suicide cases by 89% (95% CI: 57-97%). We also found that the installation of full-height PSDs resulted in the elimination of subway suicides by completely blocking access to the track area; however, half-height PSDs, which do not extend to the ceiling of the platform, were not as effective as full-height ones. Our findings were based on the data from a single subway operator for a limited period of time. Accordingly, we did not consider the possibility that some passengers choose to die at a station run by other operators. Our study did not examine the potential substitution effects of other suicide methods. Installing physical barriers at subway stations can be an effective strategy to reduce the number of subway suicides; however, half-height PSDs are not as effective as full-height ones, even when they are as high as the height of an adult. Thus, these barriers should be made high enough so that nobody can climb over them. Copyright © 2016 Elsevier B.V. All rights reserved.

Air quality inside subway metro indoor environment worldwide: A review.

PubMed

Xu, Bin; Hao, Jinliang

2017-10-01

The air quality in the subway metro indoor microenvironment has been of particular public concern. With specific reference to the growing demand of green transportation and sustainable development, subway metro systems have been rapidly developed worldwide in last decades. The number of metro commuters has continuously increased over recent years in metropolitan cities. In some cities, metro system has become the primary public transportation mode. Although commuters typically spend only 30-40min in metros, the air pollutants emitted from various interior components of metro system as well as air pollutants carried by ventilation supply air are significant sources of harmful air pollutants that could lead to unhealthy human exposure. Commuters' exposure to various air pollutants in metro carriages may cause perceivable health risk as reported by many environmental health studies. This review summarizes significant findings in the literature on air quality inside metro indoor environment, including pollutant concentration levels, chemical species, related sources and health risk assessment. More than 160 relevant studies performed across over 20 countries were carefully reviewed. These comprised more than 2000 individual measurement trips. Particulate matters, aromatic hydrocarbons, carbonyls and airborne bacteria have been identified as the primary air pollutants inside metro system. On this basis, future work could focus on investigating the chronic health risks of exposure to various air pollutants other than PM, and/or further developing advanced air purification unit to improve metro in-station air quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of noise and vibration impacts of construction and operation of the Second Avenue Subway

NASA Astrophysics Data System (ADS)

Pristera, Jessica L.

2004-05-01

An acoustical study was conducted to determine the potential for airborne noise and ground-borne noise and vibration impacts generated by construction and operation of the Second Avenue Subway. The study was performed in support of an environmental impact statement (EIS) that defined the areas along the proposed Second Avenue Subway corridor where any significiant impacts would occur as a result of construction activity and operation of the Second Avenue Subway. Using FTA guideline procedures, project-generated noise levels from subway construction and operations were determined. Construction noise levels exceeded operational noise levels. With limited alternative construction methods, practical mitigation methods were determined to reduce impacts.

Black Carbon and Particulate Matter (PM2.5) Concentrations in New York City’s Subway Stations

PubMed Central

2015-01-01

The New York City (NYC) subway is the main mode of transport for over 5 million passengers on an average weekday. Therefore, airborne pollutants in the subway stations could have a significant impact on commuters and subway workers. This study looked at black carbon (BC) and particulate matter (PM2.5) concentrations in selected subway stations in Manhattan. BC and PM2.5 levels were measured in real time using a Micro-Aethalometer and a PDR-1500 DataRAM, respectively. Simultaneous samples were also collected on quartz filters for organic and elemental carbon (OC/EC) analysis and on Teflon filters for gravimetric and trace element analysis. In the underground subway stations, mean real time BC concentrations ranged from 5 to 23 μg/m3, with 1 min average peaks >100 μg/m3, while real time PM2.5 levels ranged from 35 to 200 μg/m3. Mean EC levels ranged from 9 to 12.5 μg/m3. At street level on the same days, the mean BC and PM2.5 concentrations were below 3 and 10 μg/m3, respectively. This study shows that both BC soot and PM levels in NYC’s subways are considerably higher than ambient urban street levels and that further monitoring and investigation of BC and PM subway exposures are warranted. PMID:25409007

Black carbon and particulate matter (PM2.5) concentrations in New York City's subway stations.

PubMed

Vilcassim, M J Ruzmyn; Thurston, George D; Peltier, Richard E; Gordon, Terry

2014-12-16

The New York City (NYC) subway is the main mode of transport for over 5 million passengers on an average weekday. Therefore, airborne pollutants in the subway stations could have a significant impact on commuters and subway workers. This study looked at black carbon (BC) and particulate matter (PM2.5) concentrations in selected subway stations in Manhattan. BC and PM2.5 levels were measured in real time using a Micro-Aethalometer and a PDR-1500 DataRAM, respectively. Simultaneous samples were also collected on quartz filters for organic and elemental carbon (OC/EC) analysis and on Teflon filters for gravimetric and trace element analysis. In the underground subway stations, mean real time BC concentrations ranged from 5 to 23 μg/m(3), with 1 min average peaks >100 μg/m(3), while real time PM2.5 levels ranged from 35 to 200 μg/m(3). Mean EC levels ranged from 9 to 12.5 μg/m(3). At street level on the same days, the mean BC and PM2.5 concentrations were below 3 and 10 μg/m(3), respectively. This study shows that both BC soot and PM levels in NYC's subways are considerably higher than ambient urban street levels and that further monitoring and investigation of BC and PM subway exposures are warranted.

Subsurface Exploration Methods for Soft Ground Rapid Transit Tunnels : Volume 1. Sections 1-6 and references.

DOT National Transportation Integrated Search

1976-04-01

The objectives of the Urban Mass Transportation Administration (UMTA) Tunneling Program are to lower subway construction costs and reduce construction hazards and damage to the environment. Some measure of each of these objectives for bored tunnels a...

Guidelines for Improved Rapid Transit Tunneling Safety and Environmental Impacts : Volume 2. Environmental Impact.

DOT National Transportation Integrated Search

1977-01-01

Two of the major objectives of the Urban Mass Transportation Administration Tunneling Program are to lower subway construction costs and reduce construction hazards and damage to the environment. This study consists of a two-volume report and aims to...

Guidelines for Improved Rapid Transit Tunneling Safety and Environmental Impact : Volume 1. Safety.

DOT National Transportation Integrated Search

1977-01-01

Two of the major objectives of the Urban Mass Transportation Administration Tunneling Program are to lower subway construction costs and reduce construction hazards and damage to the environment. This study consists of a two-volume report and aims to...

Rapid Transit Subways - Maintenance Guidelines for Engineering New Installations for Reduced Maintenance

DOT National Transportation Integrated Search

1978-01-01

Economic design of new subways requires optimization of installation and maintenance costs of all the major constituent items. A prerequisite for this is an awareness of the rigorous environmental and other conditions imposed on the subway. Changing ...

Rapid Transit Subways - Guidelines for Engineering New Installations for Reduced Maintenance

DOT National Transportation Integrated Search

1978-01-01

Economic design of new subways requires optimization of installation and maintenance costs of all the major constituent items. A prerequisite for this is an awareness of the rigorous environmental and other conditions imposed on the subway. Changing ...

Subway particles are more genotoxic than street particles and induce oxidative stress in cultured human lung cells.

PubMed

Karlsson, Hanna L; Nilsson, Lennart; Möller, Lennart

2005-01-01

Epidemiological studies have shown an association between airborne particles and a wide range of adverse health effects. The mechanisms behind these effects include oxidative stress and inflammation. Even though traffic gives rise to high levels of particles in the urban air, people are exposed to even higher levels in the subway. However, there is a lack of knowledge regarding how particles from different urban subenvironments differ in toxicity. The main aim of the present study was to compare the ability of particles from a subway station and a nearby very busy urban street, respectively, to damage DNA and to induce oxidative stress. Cultured human lung cells (A549) were exposed to particles, DNA damage was analyzed using single cell gel electrophoresis (the comet assay), and the ability to induce oxidative stress was measured as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in lung cell DNA. We found that the subway particles were approximately eight times more genotoxic and four times more likely to cause oxidative stress in the lung cells. When the particles, water extracts from the particles, or particles treated with the metal chelator deferoxamine mesylate were incubated with 2'-deoxyguanosine (dG) and 8-oxodG was analyzed, we found that the oxidative capacity of the subway particles was due to redox active solid metals. Furthermore, analysis of the atomic composition showed that the subway particles to a dominating degree (atomic %) consisted of iron, mainly in the form of magnetite (Fe3O4). By using electron microscopy, the interaction between the particles and the lung cells was shown. The in vitro reactivity of the subway particles in combination with the high particle levels in subway systems give cause of concern due to the high number of people that are exposed to subway particles on a daily basis. To what extent the subway particles cause health effects in humans needs to be further evaluated.

Development of a subway operation incident delay model using accelerated failure time approaches.

PubMed

Weng, Jinxian; Zheng, Yang; Yan, Xuedong; Meng, Qiang

2014-12-01

This study aims to develop a subway operational incident delay model using the parametric accelerated time failure (AFT) approach. Six parametric AFT models including the log-logistic, lognormal and Weibull models, with fixed and random parameters are built based on the Hong Kong subway operation incident data from 2005 to 2012, respectively. In addition, the Weibull model with gamma heterogeneity is also considered to compare the model performance. The goodness-of-fit test results show that the log-logistic AFT model with random parameters is most suitable for estimating the subway incident delay. First, the results show that a longer subway operation incident delay is highly correlated with the following factors: power cable failure, signal cable failure, turnout communication disruption and crashes involving a casualty. Vehicle failure makes the least impact on the increment of subway operation incident delay. According to these results, several possible measures, such as the use of short-distance and wireless communication technology (e.g., Wifi and Zigbee) are suggested to shorten the delay caused by subway operation incidents. Finally, the temporal transferability test results show that the developed log-logistic AFT model with random parameters is stable over time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Report on Subway Tunneling Needs of 13 Selected U.S. Cities, 1971-75

DOT National Transportation Integrated Search

1972-06-01

This report establishes proposed subway tunneling construction needs for thirteen selected U.S. cities during 1971-75 as given by the transit authorities. This information will be used to estimate the demand for subway tunnel construction. This deman...

Underground

ERIC Educational Resources Information Center

Vrchota, Janet

1974-01-01

At a time when the future of New York's subway system looked bleak, new underground zoning legislation (the first ever) has been enacted. This new law requires buildings constructed near a subway station to provide transit easement space to allow public access to the subway through the building property. (MA)

Patterns of suicidal behaviour in a metro subway system: a study of 306 cases injured by the Munich subway, 1980-1999.

PubMed

Ladwig, Karl-Heinz; Baumert, Jens J

2004-09-01

As a basis for preventive strategies to reduce subway suicides, an investigation was undertaken to determine if there was a distinct pattern of subway suicidal behaviour. Data were taken from the Municipal Munich Subway System case registry (southern Germany) for all suicidal incidents on the track: purposely inflicted; date, time and location of incident, sex of victim, outcome. The analysis covered a 20 year observation period between 1980 and 1999, for which the Munich Municipal Office for Statistics also provided data of all deaths due to suicides within the city area of Munich. Suicide mortality was classified by the International Classification of Diseases, Ninth revision (codes E950-E959). A total of 306 incidents were documented with an annual mean of 16.5 cases. Case fatality was 66% (n=202). It was highest in winter and in higher aged groups. No significant time trend for incidences was observed. Median age of suicide attempters was 38 years. Most incidences (24.2%) were recorded for persons aged 20-29 years. The male: female ratio was 1.15 : 1. The peak time of day for incidences in women was during the late morning hours while significantly more men committed subway suicides during evening hours (p=0.001). No consistent seasonal variation was observed. In comparison to average suicide attempters, subjects committing subway suicides are markedly younger and they follow to a lesser extent established seasonal or circadian time patterns. More women are involved in subway suicides than would be expected. However, similarities to reports on behavioural patterns of subway suicides in other communities are striking.

Construction Monitoring of Soft Ground Tunnels : A Rational Handbook of Practices for Rapid Transit System Planners and Managers.

DOT National Transportation Integrated Search

1977-01-01

This report aims to fit the objectives of the Urban Mass Transportation Administration (UMTA) Tunneling Program - to lower subway construction costs and to reduce construction hazards and damage to the environment. This report generated from an UMTA ...

A real-time monitoring and assessment method for calculation of total amounts of indoor air pollutants emitted in subway stations.

PubMed

Oh, TaeSeok; Kim, MinJeong; Lim, JungJin; Kang, OnYu; Shetty, K Vidya; SankaraRao, B; Yoo, ChangKyoo; Park, Jae Hyung; Kim, Jeong Tai

2012-05-01

Subway systems are considered as main public transportation facility in developed countries. Time spent by people in indoors, such as underground spaces, subway stations, and indoor buildings, has gradually increased in the recent past. Especially, operators or old persons who stay in indoor environments more than 15 hr per day usually influenced a greater extent by indoor air pollutants. Hence, regulations on indoor air pollutants are needed to ensure good health of people. Therefore, in this study, a new cumulative calculation method for the estimation of total amounts of indoor air pollutants emitted inside the subway station is proposed by taking cumulative amounts of indoor air pollutants based on integration concept. Minimum concentration of individual air pollutants which naturally exist in indoor space is referred as base concentration of air pollutants and can be found from the data collected. After subtracting the value of base concentration from data point of each data set of indoor air pollutant, the primary quantity of emitted air pollutant is calculated. After integration is carried out with these values, adding the base concentration to the integration quantity gives the total amount of indoor air pollutant emitted. Moreover the values of new index for cumulative indoor air quality obtained for 1 day are calculated using the values of cumulative air quality index (CAI). Cumulative comprehensive indoor air quality index (CCIAI) is also proposed to compare the values of cumulative concentrations of indoor air pollutants. From the results, it is clear that the cumulative assessment approach of indoor air quality (IAQ) is useful for monitoring the values of total amounts of indoor air pollutants emitted, in case of exposure to indoor air pollutants for a long time. Also, the values of CCIAI are influenced more by the values of concentration of NO2, which is released due to the use of air conditioners and combustion of the fuel. The results obtained in this study confirm that the proposed method can be applied to monitor total amounts of indoor air pollutants emitted, inside apartments and hospitals as well. Nowadays, subway systems are considered as main public transportation facility in developed countries. Time spent by people in indoors, such as underground spaces, subway stations, and indoor buildings, has gradually increased in the recent past. Especially, operators or old persons who stay in the indoor environments more than 15 hr per day usually influenced a greater extent by indoor air pollutants. Hence, regulations on indoor air pollutants are needed to ensure good health of people. Therefore, this paper presents a new methodology for monitoring and assessing total amounts of indoor air pollutants emitted inside underground spaces and subway stations. A new methodology for the calculation of cumulative amounts of indoor air pollutants based on integration concept is proposed. The results suggest that the cumulative assessment approach of IAQ is useful for monitoring the values of total amounts of indoor air pollutants, if indoor air pollutants accumulated for a long time, especially NO2 pollutants. The results obtained here confirm that the proposed method can be applied to monitor total amounts of indoor air pollutants emitted, inside apartments and hospitals as well.

[To the issue on the optimization and regulation of microclimate in the subway trains and stations].

PubMed

Leksin, A G; Beresneva, T G; Kaptsov, V A; Korotich, L P; Evlampieva, M N; Timoshenkova, E V

2014-01-01

There is presented an overview of currently existing regulatory framework governing the parameters of the microclimate in the salons of subway passenger cars and stations. Analysis of the normative documents indicated that they contain very incomplete, contradictory, often unfounded information about the parameters of microclimate parameters in salons of subway rolling stock. Also, there are no clear cut hygienically-sound requirements for the work of imposed on the rolling stock subway systems provide microclimate, including new systems for air conditioning and disinfection.

Adolescent Purchasing Behavior at McDonald's and Subway.

PubMed

Lesser, Lenard I; Kayekjian, Karen C; Velasquez, Paz; Tseng, Chi-Hong; Brook, Robert H; Cohen, Deborah A

2013-10-01

To assess whether adolescents purchasing food at a restaurant marketed as "healthy" (Subway) purchase fewer calories than at a competing chain (McDonald's). We studied 97 adolescents who purchased a meal at both restaurants on different days, using each participant as his or her control. We compared the difference in calories purchased by adolescents at McDonald's and Subway in a diverse area of Los Angeles, CA. Adolescents purchased an average of 1,038 calories (standard error of the mean [SEM]: 41) at McDonald's and 955 calories (SEM 39) at Subway. The difference of 83 calories (95% confidence interval [CI]: -20 to 186) was not statistically significant (p = .11). At McDonald's, participants purchased significantly more calories from drinks (151 vs. 61, p < .01) and from side dishes (i.e., French fries or potato chips; 201 at McDonald's vs. 35 at Subway, p < .01). In contrast, they purchased fewer cups of vegetables at McDonald's (.15 vs. .57 cups, p < .01). We found that, despite being marketed as "healthy," adolescents purchasing a meal at Subway order just as many calories as at McDonald's. Although Subway meals had more vegetables, meals from both restaurants are likely to contribute to overeating. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Predicting PM10 concentration in Seoul metropolitan subway stations using artificial neural network (ANN).

PubMed

Park, Sechan; Kim, Minjeong; Kim, Minhae; Namgung, Hyeong-Gyu; Kim, Ki-Tae; Cho, Kyung Hwa; Kwon, Soon-Bark

2018-01-05

The indoor air quality of subway systems can significantly affect the health of passengers since these systems are widely used for short-distance transit in metropolitan urban areas in many countries. The particles generated by abrasion during subway operations and the vehicle-emitted pollutants flowing in from the street in particular affect the air quality in underground subway stations. Thus the continuous monitoring of particulate matter (PM) in underground station is important to evaluate the exposure level of PM to passengers. However, it is difficult to obtain indoor PM data because the measurement systems are expensive and difficult to install and operate for significant periods of time in spaces crowded with people. In this study, we predicted the indoor PM concentration using the information of outdoor PM, the number of subway trains running, and information on ventilation operation by the artificial neural network (ANN) model. As well, we investigated the relationship between ANN's performance and the depth of underground subway station. ANN model showed a high correlation between the predicted and actual measured values and it was able to predict 67∼80% of PM at 6 subway station. In addition, we found that platform shape and depth influenced the model performance. Copyright © 2017 Elsevier B.V. All rights reserved.

Creative Disruptions in the Subway of Critical Environmental Pedagogy

ERIC Educational Resources Information Center

Leduc, Timothy B.; Warkentin, Traci

2006-01-01

This paper reflects on the process of developing a pedagogy that uses experiential learning and disruption in environmental education practice to challenge students to develop critical thought. We examine our practice with university students in an "Environment and Culture" course, and focus on the processes that can transform disruption…

Factors controlling air quality in different European subway systems.

PubMed

Martins, Vânia; Moreno, Teresa; Mendes, Luís; Eleftheriadis, Konstantinos; Diapouli, Evangelia; Alves, Célia A; Duarte, Márcio; de Miguel, Eladio; Capdevila, Marta; Querol, Xavier; Minguillón, María Cruz

2016-04-01

Sampling campaigns using the same equipment and methodology were conducted to assess and compare the air quality at three South European subway systems (Barcelona, Athens and Oporto), focusing on concentrations and chemical composition of PM2.5 on subway platforms, as well as PM2.5 concentrations inside trains. Experimental results showed that the mean PM2.5 concentrations widely varied among the European subway systems, and even among different platforms within the same underground system, which might be associated to distinct station and tunnel designs and ventilation systems. In all cases PM2.5 concentrations on the platforms were higher than those in the urban ambient air, evidencing that there is generation of PM2.5 associated with the subway systems operation. Subway PM2.5 consisted of elemental iron, total carbon, crustal matter, secondary inorganic compounds, insoluble sulphate, halite and trace elements. Of all metals, Fe was the most abundant, accounting for 29-43% of the total PM2.5 mass (41-61% if Fe2O3 is considered), indicating the existence of an Fe source in the subway system, which could have its origin in mechanical friction and wear processes between rails, wheels and brakes. The trace elements with the highest enrichment in the subway PM2.5 were Ba, Cu, Mn, Zn, Cr, Sb, Sr, Ni, Sn, Co, Zr and Mo. Similar PM2.5 diurnal trends were observed on platforms from different subway systems, with higher concentrations during subway operating hours than during the transport service interruption, and lower levels on weekends than on weekdays. PM2.5 concentrations depended largely on the operation and frequency of the trains and the ventilation system, and were lower inside the trains, when air conditioning system was operating properly, than on the platforms. However, the PM2.5 concentrations increased considerably when the train windows were open. The PM2.5 levels inside the trains decreased with the trains passage in aboveground sections. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Predictors of suicide and suicide attempt in subway stations: a population-based ecological study.

PubMed

Niederkrotenthaler, Thomas; Sonneck, Gernot; Dervic, Kanita; Nader, Ingo W; Voracek, Martin; Kapusta, Nestor D; Etzersdorfer, Elmar; Mittendorfer-Rutz, Ellenor; Dorner, Thomas

2012-04-01

Suicidal behavior on the subway often involves young people and has a considerable impact on public life, but little is known about factors associated with suicides and suicide attempts in specific subway stations. Between 1979 and 2009, 185 suicides and 107 suicide attempts occurred on the subway in Vienna, Austria. Station-specific suicide and suicide attempt rates (defined as the frequency of suicidal incidents per time period) were modeled as the outcome variables in bivariate and multivariate Poisson regression models. Structural station characteristics (presence of a surveillance unit, train types used, and construction on street level versus other construction), contextual station characteristics (neighborhood to historical sites, size of the catchment area, and in operation during time period of extensive media reporting on subway suicides), and passenger-based characteristics (number of passengers getting on the trains per day, use as meeting point by drug users, and socioeconomic status of the population in the catchment area) were used as the explanatory variables. In the multivariate analyses, subway suicides increased when stations were served by the faster train type. Subway suicide attempts increased with the daily number of passengers getting on the trains and with the stations' use as meeting points by drug users. The findings indicate that there are some differences between subway suicides and suicide attempts. Completed suicides seem to vary most with train type used. Suicide attempts seem to depend mostly on passenger-based characteristics, specifically on the station's crowdedness and on its use as meeting point by drug users. Suicide-preventive interventions should concentrate on crowded stations and on stations frequented by risk groups.

Analysis of Subway Interior Noise at Peak Commuter Time.

PubMed

Lee, Donguk; Kim, Gibbeum; Han, Woojae

2017-07-01

Although mass transit systems are convenient and efficient for urban people, little attention has been paid to the potential hearing hazard from their noise. The purpose of the current study was to measure and analyze levels of subway interior noise at peak commuter times and to provide information about commuters' daily dose of noise exposure. To measure the subway interior noise, nine subway lines inside Seoul (i.e., lines 1-9) and six lines surrounding the capital city area (i.e., Central, Bundang, Sinbundang, Incheon, Gyeongui, and Gyeongchun) were chosen. The noise was measured and recorded by a sound level meter for two-hour periods in the morning and evening. 1) In the LZeq analysis, the average noise level of all 15 lines was 72.78 dB; the maximum and minimum noise levels were 78.34 and 62.46 dB, respectively. The average noise level of the nine lines inside Seoul was 73.45 dB, which was 1.68-dB louder than that of the six lines surrounding the capital city area. 2) Based on the LZeq analysis of 33 measured frequencies, 12.5 Hz was the highest frequency and 20,000 Hz was the lowest. 3) There was no remarkable difference in the level of subway interior noise between morning and evening peak commuter times. We concluded that the level of subway interior noise was not loud enough for commuters to incur noise-induced hearing loss. Regardless, environmental noise control efforts in the subway system might be needed for commuters who take a subway every day.

The Usefulness of Tactual Maps of the New York City Subway System.

ERIC Educational Resources Information Center

Luxton, K.; And Others

1994-01-01

Sixteen people with blindness or visual impairments used three different types of tactual maps of the New York City subway system presenting information at three levels of specificity. Results indicated that the tactual maps improved participants' attitudes toward the subway and benefited blind as well as low vision participants. (Author/DB)

Exposure to airborne particulate matter in the subway system.

PubMed

Martins, Vânia; Moreno, Teresa; Minguillón, María Cruz; Amato, Fulvio; de Miguel, Eladio; Capdevila, Marta; Querol, Xavier

2015-04-01

The Barcelona subway system comprises eight subway lines, at different depths, with different tunnel dimensions, station designs and train frequencies. An extensive measurement campaign was performed in this subway system in order to characterise the airborne particulate matter (PM) measuring its concentration and investigating its variability, both inside trains and on platforms, in two different seasonal periods (warmer and colder), to better understand the main factors controlling it, and therefore the way to improve air quality. The majority of PM in the underground stations is generated within the subway system, due to abrasion and wear of rail tracks, wheels and braking pads caused during the motion of the trains. Substantial variation in average PM concentrations between underground stations was observed, which might be associated to different ventilation and air conditioning systems, characteristics/design of each station and variations in the train frequency. Average PM2.5 concentrations on the platforms in the subway operating hours ranged from 20 to 51 and from 41 to 91 μg m(-3) in the warmer and colder period, respectively, mainly related to the seasonal changes in the subway ventilation systems. The new subway lines with platform screen doors showed PM2.5 concentrations lower than those in the conventional system, which is probably attributable not only to the more advanced ventilation setup, but also to the lower train frequency and the design of the stations. PM concentrations inside the trains were generally lower than those on the platforms, which is attributable to the air conditioning systems operating inside the trains, which are equipped with air filters. This study allows the analysis and quantification of the impact of different ventilation settings on air quality, which provides an improvement on the knowledge for the general understanding and good management of air quality in the subway system. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Urban Transit System Microbial Communities Differ by Surface Type and Interaction with Humans and the Environment

PubMed Central

Hsu, Tiffany; Joice, Regina; Vallarino, Jose; Abu-Ali, Galeb; Hartmann, Erica M.; Shafquat, Afrah; DuLong, Casey; Baranowski, Catherine; Gevers, Dirk; Green, Jessica L.; Spengler, John D.

2016-01-01

ABSTRACT Public transit systems are ideal for studying the urban microbiome and interindividual community transfer. In this study, we used 16S amplicon and shotgun metagenomic sequencing to profile microbial communities on multiple transit surfaces across train lines and stations in the Boston metropolitan transit system. The greatest determinant of microbial community structure was the transit surface type. In contrast, little variation was observed between geographically distinct train lines and stations serving different demographics. All surfaces were dominated by human skin and oral commensals such as Propionibacterium, Corynebacterium, Staphylococcus, and Streptococcus. The detected taxa not associated with humans included generalists from alphaproteobacteria, which were especially abundant on outdoor touchscreens. Shotgun metagenomics further identified viral and eukaryotic microbes, including Propionibacterium phage and Malassezia globosa. Functional profiling showed that Propionibacterium acnes pathways such as propionate production and porphyrin synthesis were enriched on train holding surfaces (holds), while electron transport chain components for aerobic respiration were enriched on touchscreens and seats. Lastly, the transit environment was not found to be a reservoir of antimicrobial resistance and virulence genes. Our results suggest that microbial communities on transit surfaces are maintained from a metapopulation of human skin commensals and environmental generalists, with enrichments corresponding to local interactions with the human body and environmental exposures. IMPORTANCE Mass transit environments, specifically, urban subways, are distinct microbial environments with high occupant densities, diversities, and turnovers, and they are thus especially relevant to public health. Despite this, only three culture-independent subway studies have been performed, all since 2013 and all with widely differing designs and conclusions. In this study, we profiled the Boston subway system, which provides 238 million trips per year overseen by the Massachusetts Bay Transportation Authority (MBTA). This yielded the first high-precision microbial survey of a variety of surfaces, ridership environments, and microbiological functions (including tests for potential pathogenicity) in a mass transit environment. Characterizing microbial profiles for multiple transit systems will become increasingly important for biosurveillance of antibiotic resistance genes or pathogens, which can be early indicators for outbreak or sanitation events. Understanding how human contact, materials, and the environment affect microbial profiles may eventually allow us to rationally design public spaces to sustain our health in the presence of microbial reservoirs. Author Video: An author video summary of this article is available. PMID:27822528

Development of the safety control framework for shield tunneling in close proximity to the operational subway tunnels: case studies in mainland China.

PubMed

Li, Xinggao; Yuan, Dajun

2016-01-01

China's largest cities like Beijing and Shanghai have seen a sharp increase in subway network development as a result of the rapid urbanization in the last decade. The cities are still expanding their subway networks now, and many shield tunnels are being or will be constructed in close proximity to the existing operational subway tunnels. The execution plans for the new nearby shield tunnel construction calls for the development of a safety control framework-a set of control standards and best practices to help organizations manage the risks involved. Typical case studies and relevant key technical parameters are presented with a view to presenting the resulting safety control framework. The framework, created through collaboration among the relevant parties, addresses and manages the risks in a systematic way based on actual conditions of each tunnel crossing construction. The framework consists of six parts: (1) inspecting the operational subway tunnels; (2) deciding allowed movements of the existing tunnels and tracks; (3) simulating effects of the shield tunneling on the existing tunnels; (4) doing preparation work; (5) monitoring design and information management; and (6) measures and activation mechanism of the countermeasures. The six components are explained and demonstrated in detail. In the end, discussions made involve construction and post-construction settlement of the operational tunnel, application of the remedial grouting to rectify excessive settlements of the operational tunnel, and use of the innovative tool of the optical fiber measurement for tunnel movement monitoring. It is concluded that the construction movement of the tunnel can be controlled within 15 mm when the shield machine is <7 m in excavation diameter. The post-construction settlement of the tunnel buried in the very soft ground is much greater than its construction settlement, and last several years until reaching a final stable state. Two cases are outlined to demonstrate the feasibility of using the remedial grouting to reduce the long-term settlement of the operational tunnels. The more and more segmental tunnels being constructed, there is an increasing need of the optical fiber measurement for tunnel movement monitoring in the near future.

49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 9 2010-10-01 2010-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... RAILROADS 1 Operating Expenses-Way and Structures § 1242.15 Roadway, tunnels and subways, bridges and...

76 FR 40447 - Notice of Proposed Buy America Waiver To Allow Bidder To Certify Compliance

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-08

... Subway project to certify compliance with Buy America. The bidder certified non-compliance based on a... Second Avenue Subway project. If granted, this waiver would be limited to the procedural aspects of the... for a contract to construct the 86th Street Station for its Second Avenue Subway project, a $4.8...

Analysis of Subway Interior Noise at Peak Commuter Time

PubMed Central

Lee, Donguk; Kim, Gibbeum; Han, Woojae

2017-01-01

Background and Objectives Although mass transit systems are convenient and efficient for urban people, little attention has been paid to the potential hearing hazard from their noise. The purpose of the current study was to measure and analyze levels of subway interior noise at peak commuter times and to provide information about commuters’ daily dose of noise exposure. Materials and Methods To measure the subway interior noise, nine subway lines inside Seoul (i.e., lines 1-9) and six lines surrounding the capital city area (i.e., Central, Bundang, Sinbundang, Incheon, Gyeongui, and Gyeongchun) were chosen. The noise was measured and recorded by a sound level meter for two-hour periods in the morning and evening. Results 1) In the LZeq analysis, the average noise level of all 15 lines was 72.78 dB; the maximum and minimum noise levels were 78.34 and 62.46 dB, respectively. The average noise level of the nine lines inside Seoul was 73.45 dB, which was 1.68-dB louder than that of the six lines surrounding the capital city area. 2) Based on the LZeq analysis of 33 measured frequencies, 12.5 Hz was the highest frequency and 20,000 Hz was the lowest. 3) There was no remarkable difference in the level of subway interior noise between morning and evening peak commuter times. Conclusions We concluded that the level of subway interior noise was not loud enough for commuters to incur noise-induced hearing loss. Regardless, environmental noise control efforts in the subway system might be needed for commuters who take a subway every day. PMID:28704890

Suicidal behaviour on subway systems: a review of the epidemiology.

PubMed

Ratnayake, Ruwan; Links, Paul S; Eynan, Rahel

2007-11-01

Suicide on subway systems is a public health challenge that has been reported in urban centers worldwide. Our objective was to analyze studies of suicide on subway systems, develop a profile of characteristics that are suggestive of association with suicides or attempts, and show how this profile can inform prevention. A literature review involving epidemiology studies and studies relating to subway suicide was conducted. Twenty-eight studies were included in this review. Across studies, characteristics were not often assessed for risk factor status, although several characteristics were remarkably similar. Those attempting suicide on the subway appear to be affected by serious mental illness and have contact with mental health services before the suicidal behavior. Several characteristics may be shared among this population, emphasizing the potential for prevention in clinical and public health domains. Well-designed studies that utilize robust data collection and statistical methods are needed to establish the risk status associated with these characteristics.

Environmental trade-offs of tunnels vs cut-and-cover subways

USGS Publications Warehouse

Walton, M.

1978-01-01

Heavy construction projects in cities entail two kinds of cost - internal cost, which can be defined in terms of payments from one set of parties to another, and external cost, which is the cost borne by the community at large as the result of disutilities entailed in construction and operation. Environmental trade-offs involve external costs, which are commonly difficult to measure. Cut-and-cover subway construction probably entails higher external and internal cost than deep tunnel construction in many urban geological environments, but uncertainty concerning the costs and environmental trade-offs of tunneling leads to limited and timid use of tunneling by American designers. Thus uncertainty becomes a major trade-off which works against tunneling. The reverse is true in Sweden after nearly 30 years of subway construction. Econometric methods for measuring external costs exist in principle, but are limited in application. Economic theory based on market pressure does not address the real problem of urban environmental trade-offs. Nevertheless, the problem of uncertainty can be addressed by comparative studies of estimated and as-built costs of cut-and-cover vs tunnel projects and a review of environmental issues associated with such construction. Such a study would benefit the underground construction industry and the design of transportation systems. It would also help solve an aspect of the urban problem. ?? 1978.

Investigation of air pollution of Shanghai subway stations in ventilation seasons in terms of PM2.5 and PM10.

PubMed

Guo, Erbao; Shen, Henggen; He, Lei; Zhang, Jiawen

2017-07-01

In November 2015, the PM 2.5 and PM 10 particulate matter (PM) levels in platforms, station halls, and rail areas of the Shangcheng and Jiashan Road Station were monitored to investigate air pollution in the Shanghai subway system. The results revealed that in subway stations, PM 2.5 and PM 10 concentrations were significantly higher than those in outdoor environments. In addition, particle concentrations in the platforms exceeded maximum levels that domestic safety standards allowed. Particularly on clear days, PM 2.5 and PM 10 concentrations in platforms were significantly higher than maximum standards levels. Owing to the piston effect, consistent time-varying trends were exhibited by PM 2.5 concentrations in platforms, station halls, and rail areas. Platform particle concentrations were higher than the amount in station halls, and they were higher on clear days than on rainy days. The time-varying trends of PM 10 and PM 2.5 concentrations in platforms and station halls were similar to each other. Activities within the station led to most of the inhalable particles within the station area. The mass concentration ratios of PM 2.5 and PM 10 in platforms were within 0.65-0.93, and fine particles were the dominant components.

Predictive monitoring and diagnosis of periodic air pollution in a subway station.

PubMed

Kim, YongSu; Kim, MinJung; Lim, JungJin; Kim, Jeong Tai; Yoo, ChangKyoo

2010-11-15

The purpose of this study was to develop a predictive monitoring and diagnosis system for the air pollutants in a subway system using a lifting technique with a multiway principal component analysis (MPCA) which monitors the periodic patterns of the air pollutants and diagnoses the sources of the contamination. The basic purpose of this lifting technique was to capture the multivariate and periodic characteristics of all of the indoor air samples collected during each day. These characteristics could then be used to improve the handling of strong periodic fluctuations in the air quality environment in subway systems and will allow important changes in the indoor air quality to be quickly detected. The predictive monitoring approach was applied to a real indoor air quality dataset collected by telemonitoring systems (TMS) that indicated some periodic variations in the air pollutants and multivariate relationships between the measured variables. Two monitoring models--global and seasonal--were developed to study climate change in Korea. The proposed predictive monitoring method using the lifted model resulted in fewer false alarms and missed faults due to non-stationary behavior than that were experienced with the conventional methods. This method could be used to identify the contributions of various pollution sources. Copyright © 2010 Elsevier B.V. All rights reserved.

Interaction of subway LIM vehicle with ballasted track in polygonal wheel wear development

NASA Astrophysics Data System (ADS)

Li, Ling; Xiao, Xin-Biao; Jin, Xue-Song

2011-04-01

This paper develops a coupled dynamics model for a linear induction motor (LIM) vehicle and a subway track to investigate the influence of polygonal wheels of the vehicle on the dynamic behavior of the system. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom. A Timoshenko beam is used to model the rails which are discretely supported by sleepers. The sleepers are modeled as rigid bodies with their vertical, lateral, and rolling motions being considered. In order to simulate the vehicle running along the track, a moving sleeper support model is introduced to simulate the excitation by the discrete sleeper supporters, in which the sleepers are assumed to move backward at a constant speed that is the same as the train speed. The Hertzian contact theory and the Shen-Hedrick-Elkins' model are utilized to deal with the normal dynamic forces and the tangential forces between wheels and rails, respectively. In order to better characterize the linear metro system (LMS), Euler beam theory based on modal superposition method is used to model LIM and RP. The vertical electric magnetic force and the lateral restoring force between the LIM and RP are also taken into consideration. The former has gap-varying nonlinear characteristics, whilst the latter is considered as a constant restoring force of 1 kN. The numerical analysis considers the effect of the excitation due to polygonal wheels on the dynamic behavior of the system at different wear stages, in which the used data regarding the polygonal wear on the wheel tread are directly measured at the subway site.

Concentrations, properties, and health risk of PM2.5 in the Tianjin City subway system.

PubMed

Wang, Bao-Qing; Liu, Jian-Feng; Ren, Zi-Hui; Chen, Rong-Hui

2016-11-01

A campaign was conducted to assess and compare the personal exposure in L3 of Tianjin subway, focusing on PM 2.5 levels, chemical compositions, morphology analysis, as well as the health risk of heavy metal in PM 2.5 . The results indicated that the average concentration of the PM 2.5 was 151.43 μg/m 3 inside the train of the subway during rush hours. PM 2.5 concentrations inside car under the ground are higher than those on the ground, and PM 2.5 concentrations on the platform are higher than those inside car. Regarding metal concentrations, the highest element in PM 2.5 samples was Fe; the level of which is 17.55 μg/m 3 . OC is a major component of PM 2.5 in Tianjin subway. Secondary organic carbon is the formation of gaseous organic pollutants in subway. SEM-EDX and TEM-EDX exhibit the presence of individual particle with a large metal content in the subway samples. For small Fe metal particles, iron oxide can be formed easily. With regard to their sources, Fe-containing particles are generated mainly from mechanical wear and friction processes at the rail-wheel-brake interfaces. The non-carcinogenic risk to metals Cr, Ni, Cu, Zn and Pb, and carcinogenic hazard of Cr and Ni were all below the acceptable level in L3 of Tianjin subway.

A case study on stratified settlement and rebound characteristics due to dewatering in Shanghai subway station.

PubMed

Wang, Jianxiu; Huang, Tianrong; Sui, Dongchang

2013-01-01

Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR) of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found in sandy clay, but both positive and negative rebound occurred in the silty clay, and the absolute value of rebound in sandy clay was larger than in silty clay, and the mechanism of SSR was discussed with mechanical sandwich model, and it was found that the load and cohesive force of different soils was the main source of different responses when decompressed.

Improving a workstation in an existing cab by means of a participatory approach: the case of subway operators' workstations.

PubMed

Bellemare, Marie; Beaugrand, Sylvie; Larue, Christian; Champoux, Danièle

2009-01-01

A study was conducted to identify possible solutions for redesigning a subway cab in order to improve the posture of drivers working in a restricted space. The approach used included the participation of a working group comprised of operations, maintenance, and engineering managers as well as several drivers. After 6 meetings in which different simulation techniques were used, the working group proposed changes for increasing the available space inside the cab and three seat designs. The involvement of the actors from the three departments affected by the changes, as well as the operators, throughout the process, was a determining factor in the advancement and acceptance of the projects. The fact that 400 cars are currently in service and must be modified means that it will take several years to implement the modifications in the entire fleet.

A Case Study on Stratified Settlement and Rebound Characteristics due to Dewatering in Shanghai Subway Station

PubMed Central

Wang, Jianxiu; Huang, Tianrong; Sui, Dongchang

2013-01-01

Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR) of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found in sandy clay, but both positive and negative rebound occurred in the silty clay, and the absolute value of rebound in sandy clay was larger than in silty clay, and the mechanism of SSR was discussed with mechanical sandwich model, and it was found that the load and cohesive force of different soils was the main source of different responses when decompressed. PMID:23878521

[MICROCLIMATE CONDITION IN SUBWAY CARS IN THE SUMMER PERIOD OF THE YEAR].

PubMed

Leksin, A G; Evlampieva, M N; Timoshenkova, E V; Morgunov, A V; Kaptsov, V A

2015-01-01

There are presented the results of the work, which aims to identify the relationship between the temperature of air in the salons of subway cars from the heat output of passengers in different people occupancy of cars during "peak hours", and to determine the efficacy offorced air handling regular ventilation or air conditioning system to remove the elevated heat load on passengers. In the work there was used the method of calculating the amount of heat output of 215 passengers (nominal fullness of the chamber) and the simulation method of heat and moisture output of the same number of passengers. The operating system of ventilation has been shown to fail to decline the average temperature of the air in the passenger compartment to the optimum values and most efficient approach for the reducing the heat load on the passengers is the use of air conditioning systems.

Public Health Lessons Learned From Analysis of New York City Subway Injuries

PubMed Central

Guth, Amber A.; O’Neill, Andrea; Pachter, H. Leon; Diflo, Thomas

2006-01-01

Serious subway injuries are devastating to their young victims and have high rates of mortality and amputation. We identified the urban population at greatest risk for subway injuries and investigated the influence of local economies on injury rates. We propose using changes in social conditions as a “trigger” for increased vigilance and protective measures at times of higher risk. PMID:16449596

Whole-body vibration exposure in subway cars and review of adverse health effects.

PubMed

Johanning, E; Wilder, D G; Landrigan, P J; Pope, M H

1991-05-01

New York City Transit Authority subway operators have a high prevalence of back problems. To evaluate a possible dose-response relationship for whole-body vibration, we studied subway car vibrations measured and analyzed according to the International Standard Organization 2631 and Verein Deutscher Ingenieure 2057 standards. Vibration transducers in triaxial orientation were mounted in a disc pad directly on the subway operator's seat. The relatively high lateral and vertical accelerations, primarily the combined effects, may all contribute to the high rate of musculoskeletal complaints, especially of the lower back. Other factors aggravating whole-body vibrations include primitive ergonomic cab and seat design, forced body posture, high noise levels, and organizational work stress.

Avoiding Pandemic Fears in the Subway and Conquering the Platypus.

PubMed

Gonzalez, A; Vázquez-Baeza, Y; Pettengill, J B; Ottesen, A; McDonald, D; Knight, R

2016-01-01

Metagenomics is increasingly used not just to show patterns of microbial diversity but also as a culture-independent method to detect individual organisms of intense clinical, epidemiological, conservation, forensic, or regulatory interest. A widely reported metagenomic study of the New York subway suggested that the pathogens Yersinia pestis and Bacillus anthracis were part of the "normal subway microbiome." In their article in mSystems, Hsu and collaborators (mSystems 1(3):e00018-16, 2016, http://dx.doi.org/10.1128/mSystems.00018-16) showed that microbial communities on transit surfaces in the Boston subway system are maintained from a metapopulation of human skin commensals and environmental generalists and that reanalysis of the New York subway data with appropriate methods did not detect the pathogens. We note that commonly used software pipelines can produce results that lack prima facie validity (e.g., reporting widespread distribution of notorious endemic species such as the platypus or the presence of pathogens) but that appropriate use of inclusion and exclusion sets can avoid this issue.

Exposure level and distribution characteristics of airborne bacteria and fungi in Seoul metropolitan subway stations.

PubMed

Kim, Ki Youn; Kim, Yoon Shin; Kim, Daekeun; Kim, Hyeon Tae

2011-01-01

The exposure level and distribution characteristics of airborne bacteria and fungi were assessed in the workers' activity areas (station office, bedroom, ticket office and driver's seat) and passengers' activity areas (station precinct, inside the passenger carriage, and platform) of the Seoul metropolitan subway. Among investigated areas, the levels of airborne bacteria and fungi in the workers' bedroom and station precincts were relatively high. No significant difference was found in the concentration of airborne bacteria and fungi between the underground and above ground activity areas of the subway. The genera identified in all subway activity areas with a 5% or greater detection rate were Staphylococcus, Micrococcus, Bacillus and Corynebacterium for airborne bacteria and Penicillium, Cladosporium, Chrysosporium, Aspergillus for airborne fungi. Staphylococcus and Micrococcus comprised over 50% of the total airborne bacteria and Penicillium and Cladosporium comprised over 60% of the total airborne fungi, thus these four genera are the predominant genera in the subway station.

Magnetic and geochemical characterization of iron pollution in subway dusts in Shanghai, China

NASA Astrophysics Data System (ADS)

Zhang, Weiguo; Jiang, Huimin; Dong, Chenyin; Yan, Qun; Yu, Lizhong; Yu, Yang

2011-06-01

Dust samples collected from subway platforms in Shanghai, China, have been examined using magnetic measurements and geochemical analysis. Our results indicate that the Shanghai subway platform dusts have extremely strong magnetic signatures. These results, combined with X-ray diffraction analysis and scanning and transmission electron microscope examinations, indicate that the magnetic mineralogy of the dust is dominated by iron scraps due to wheel-rail mechanical abrasion and spherules rich in magnetite from fossil fuel combustion. Although the magnetic particles are primarily micrometer sized, fine submicron magnetic grains are also evident in the dust. The underground platform dusts have a much higher iron flake abundance and magnetic susceptibility than those from aboveground platforms because the latter ones are diluted by inputs of magnetically weaker ambient aerosols with a higher proportion of magnetite spherules. Geochemical analysis indicates that underground platform dusts have elevated Fe and Mn, but lower Al and Ti contents relative to aboveground subway dust. This is consistent with the closed nature of underground platforms, which therefore reduces exposure to soil-derived dust. Since the adverse environmental effects of subway particles may be linked to higher contents of iron and other metals, our results demonstrate that magnetic measurements provide a novel and effective approach for characterizing iron mineralogy and grain size in subway dusts.

Indoor Air Quality in the Metro System in North Taiwan.

PubMed

Chen, Ying-Yi; Sung, Fung-Chang; Chen, Mei-Lien; Mao, I-Fang; Lu, Chung-Yen

2016-12-02

Indoor air pollution is an increasing health concern, especially in enclosed environments such as underground subway stations because of increased global usage by urban populations. This study measured the indoor air quality of underground platforms at 10 metro stations of the Taipei Rapid Transit system (TRTS) in Taiwan, including humidity, temperature, carbon monoxide (CO), carbon dioxide (CO₂), formaldehyde (HCHO), total volatile organic compounds (TVOCs), ozone (O₃), airborne particulate matter (PM 10 and PM 2.5 ), bacteria and fungi. Results showed that the CO₂, CO and HCHO levels met the stipulated standards as regulated by Taiwan's Indoor Air Quality Management Act (TIAQMA). However, elevated PM 10 and PM 2.5 levels were measured at most stations. TVOCs and bacterial concentrations at some stations measured in summer were higher than the regulated standards stipulated by Taiwan's Environmental Protection Administration. Further studies should be conducted to reduce particulate matters, TVOCs and bacteria in the air of subway stations.

Subway-Related Trauma: An Urban Public Health Issue with a High Case-Fatality Rate.

PubMed

Rodier, Simon G; DiMaggio, Charles J; Wall, Stephen; Sim, Vasiliy; Frangos, Spiros G; Ayoung-Chee, Patricia; Bukur, Marko; Tandon, Manish; Todd, S Rob; Marshall, Gary T

2018-05-09

Between 1990 and 2003, there were 668 subway-related fatalities in New York City. However, subway-related trauma remains an understudied area of injury-related morbidity and mortality. The objective of this study was to characterize the injuries and events leading up to the injuries of all patients admitted after subway-related trauma. We conducted a retrospective case series of subway-related trauma at a Level I trauma center from 2001 to 2016. Descriptive epidemiology of patient demographics, incident details, injuries, and outcomes were analyzed. Over 15 years, 254 patients were admitted for subway-related trauma. The mean (standard error of the mean) age was 41 (1.0) years, 80% were male (95% confidence interval [CI] 74-84%) and median Injury Severity Score was 14 (interquartile range [IQR] 5-24). The overall case-fatality rate was 10% (95% CI 7-15%). The most common injuries were long-bone fractures, intracranial hemorrhage, and traumatic amputations. Median length of stay was 6 days (IQR 1-18 days). Thirty-seven percent of patients required surgical intervention. At the time of injury, 55% of patients (95% CI 49-61%) had a positive urine drug or alcohol screen, 16% (95% CI 12-21%) were attempting suicide, and 39% (95% CI 33-45%) had a history of psychiatric illness. Subway-related trauma is associated with a high case-fatality rate. Alcohol or drug intoxication and psychiatric illness can increase the risk of this type of injury. Copyright © 2018 Elsevier Inc. All rights reserved.

Polycyclic aromatic hydrocarbons (PAH) and diesel engine emission (elemental carbon) inside a car and a subway train.

PubMed

Fromme, H; Oddoy, A; Piloty, M; Krause, M; Lahrz, T

1998-06-30

Significant concentrations of potentially harmful substances can be present in the interior of vehicles. The main sources of PAHs and elemental carbon (EC) inside a car are likely to be combustion emissions, especially from coal and traffic. The same sources can also be important for the interior of a subway train for which there are specific sources in the tunnel system, for example diesel engines. Twice, in summer 1995 and winter 1996 polycyclic aromatic hydrocarbons (PAH) and diesel motor emission (estimated as elemental carbon) were determined in the interior of a car (a 2-year-old VW Golf with a three-way catalytic converter) and in the passenger compartment of a subway train (below ground). On each sampling day (in total 16 daily measurements in the car and 16 in the subway) the substances were determined in the breathing zone of the passengers from 07:00 h to 16:00 h under different meteorologic conditions (winter- and summertime). The car followed the route of the subway from the western Berlin borough of Spandau to the south-eastern borough of Neukölln, and back. The sampling represented a realistic exposure model for driving in a high traffic and polluted urban area. The electric subway train (also 2 years in use) connected the same parts of Berlin (31 km underground). The mean values obtained during the two measurement periods (summer/winter) inside the car were 1.0 and 3.2 ng/m3 for benzo[a]pyrene, 10.2 and 28.7 ng/m3 for total-measured-PAHs, 14.1 and 8.2 micrograms/m3 for EC and in the subway 0.7 and 4.0 ng/m3 for benzol[a]pyrene, 30.2 and 67.5 ng/m3 for total PAHs, 109 and 6.9 micrograms/m3 for EC. A comparison between subway and car exposures shows significantly higher concentrations of PAHs in the subway train, which can be explained by relatively high concentrations of fluoranthene and pyrene in the subway. So far a satisfactory explanation has not been found, but one source might be the wooden railway ties which were formerly preserved with tar based products. In wintertime in both transportation systems the concentrations of beno[a]pyrene are three to four times higher than in summer corresponding to the changing of the ambient air concentrations.

Getting People to Parks,

DTIC Science & Technology

1976-04-01

2 The area is served by the most extensive transit systems in the world , including subways , surface rail and bus systems, and many miles of...private car. The median trip time of visitors to Jacob Riis Park (Brooklyn) using the subway was three times as long as the time taken by motorists...alternatives are discussed below. Subway Urban mass transit systems are geared to the job of moving large numbers of people to work in the morning and

Sub-parts-per-billion level detection of dimethyl methyl phosphonate (DMMP) by quantum cascade laser photoacoustic spectroscopy.

PubMed

Mukherjee, Anadi; Dunayevskiy, Ilya; Prasanna, Manu; Go, Rowel; Tsekoun, Alexei; Wang, Xiaojun; Fan, Jenyu; Patel, C Kumar N

2008-04-01

The need for the detection of chemical warfare agents (CWAs) is no longer confined to battlefield environments because of at least one confirmed terrorist attack, the Tokyo Subway [Emerg. Infect. Dis. 5, 513 (1999)] in 1995, and a suspected, i.e., a false-alarm of a CWA in the Russell Senate Office Building [Washington Post, 9 February 2006, p. B01]. Therefore, detection of CWAs with high sensitivity and low false-alarm rates is considered an important priority for ensuring public safety. We report a minimum detection level for a CWA simulant, dimethyl methyl phosphonate (DMMP), of <0.5 ppb (parts in 10(9)) by use of a widely tunable external grating cavity quantum cascade laser and photoacoustic spectroscopy. With interferents present in Santa Monica, California street air, we demonstrate a false-alarm rate of 1:10(6) at a detection threshold of 1.6 ppb.

Association of Subway Driver's Depressive Symptoms and Experience of Work-Related Problems.

PubMed

Jo, Sun-Jin; Yim, Hyeon Woo; Kim, Hyoung-Ryoul; Lee, Kang Sook; Park, Jong-Ik; Chang, Sung Man

2010-12-03

Subway drivers experience various types of work-related problems during their driving, and those experiences can act as risk factors for depressive symptoms. This study was conducted to investigate the association between work-related problems and subway driver's depressive symptoms. We recruited all of the 961 current subway drivers of a subway company located in Seoul, South Korea and conducted a survey of their socio-demographic and vocational characteristics, hospital visits as an outpatient or inpatient, and work-related problem experiences during the last year. Work-related problems included an accident resulting in death or injury, a conflict with a customer, a sudden stop from an emergency bell, or a near accident. Depressive symptoms were measured with the Center for Epidemiologic Studies-Depression (CES-D) instrument. The survey was performed using a self-report questionnaire from April 16 to July 13, 2007. The data of 827 drivers (86.2%) were analyzed. Experience of a conflict with a passenger (p=0.011), a sudden stop from an emergency bell (p=0.001), or a near accident (p=0.001) increased the prevalence of depressive symptoms among subway drivers. A multiple logistic regression analysis revealed that a sudden stop from an emergency bell increased the risk of depressive symptoms significantly (OR=2.59, p=0.026). Near accidents were marginally associated with a higher risk for depressive symptoms (OR=1.62, p=0.062). The experience of a sudden stop from an emergency bell increased subway driver's depressive symptoms, and near accidents may increase the risk of depressive symptoms. Therefore, interventions for the drivers who had experienced these work-related problems are needed.

Manganese concentrations in the air of the Montreal (Canada) subway in relation to surface automobile traffic density.

PubMed

Boudia, Nacéra; Halley, Renée; Kennedy, Greg; Lambert, Jean; Gareau, Lise; Zayed, Joseph

2006-07-31

Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic derivative of manganese (Mn), used since 1976 in Canadian gasoline as an octane enhancer. Its combustion leads to the emission of Mn particles. Several studies carried out by our research group have established a correlation between atmospheric Mn concentrations and automobile traffic density, suggesting that MMT in gasoline could play a significant role. This study aims to measure Mn concentrations in the air of the underground subway in Montreal (Canada) and to examine the relation with nearby surface automobile traffic density and, by extension, with the use of MMT in gasoline. Three subway stations were chosen for their location in different microenvironments with different traffic densities. Respirable (MnR<5 microm) and total Mn (MnT) were sampled over two weeks, 5 days/week, 12 h/day. For the station located in the lower traffic density area, relatively low levels of MnR and MnT were found, with averages of 0.018 and 0.032 microg/m(3), respectively. These concentrations are within the range of the background levels in Montreal. For the other two stations, the average concentrations of MnR were twice as high and exceeded the US EPA reference concentration of 0.05 microg/m(3). Although there may be several sources of Mn from different components of the subway structure and vehicles, no correlation was found between subway traffic and atmospheric Mn in the subway. Since the air in the underground subway is pumped directly from outside without filtration, our findings strongly suggest that the combustion of MMT in automobiles is an important factor.

21ST Century Terrorism: Wrong Diagnosis, Inadequate Remedy

DTIC Science & Technology

2005-06-01

London: Croom Helm, 1975), p. 15. 38 The Oklahoma bombing, the WTC attack in 1993 and the Tokyo subway sarin gas attack are the examples used by...the Tokyo subway that could have actually caused far more casualties than the 12 deaths that it did.41 This last case is very important, since in...aforementioned Tokyo subway attack is the proof of a clear and present danger. Last but not least, bio-terrorism is another possible “new terrorism

Avoiding Pandemic Fears in the Subway and Conquering the Platypus

PubMed Central

Vázquez-Baeza, Y.; Pettengill, J. B.; Ottesen, A.; McDonald, D.; Knight, R.

2016-01-01

ABSTRACT Metagenomics is increasingly used not just to show patterns of microbial diversity but also as a culture-independent method to detect individual organisms of intense clinical, epidemiological, conservation, forensic, or regulatory interest. A widely reported metagenomic study of the New York subway suggested that the pathogens Yersinia pestis and Bacillus anthracis were part of the “normal subway microbiome.” In their article in mSystems, Hsu and collaborators (mSystems 1(3):e00018-16, 2016, http://dx.doi.org/10.1128/mSystems.00018-16) showed that microbial communities on transit surfaces in the Boston subway system are maintained from a metapopulation of human skin commensals and environmental generalists and that reanalysis of the New York subway data with appropriate methods did not detect the pathogens. We note that commonly used software pipelines can produce results that lack prima facie validity (e.g., reporting widespread distribution of notorious endemic species such as the platypus or the presence of pathogens) but that appropriate use of inclusion and exclusion sets can avoid this issue. PMID:27832215

Electrical injury from subway third rails: serious injury associated with intermediate voltage contact.

PubMed

Rabban, J; Adler, J; Rosen, C; Blair, J; Sheridan, R

1997-09-01

Railway and subway-associated electrical trauma is rare and typically involves high voltage (> 20,000) arc injuries. Not all rail systems utilize such high voltage. We report 16 cases of electrical trauma due to 600 V direct contact with subway 'third' rails. A case series of injured patients presenting to Shriners Burns Institute, Boston or Massachusetts General Hospital between 1970 and 1995 was retrospectively analyzed. A total of 16 cases was identified. Among seven subway workers, the mechanism of rail contact was unintentional by a tool, a hand or by falling; no deaths occurred. Among nine non-occupational victims, injuries involved suicide attempts, unintentional falls, or risk-taking behavior. This group suffered greater burn severity, operative procedures, and complications; three deaths occurred. This is the largest report series of direct electrical trauma from a subway third rail. The high morbidity and mortality from this 600 V contact suggests that the traditional classification of low voltage (< 1000 V) exposure can be subdivided to reflect the serious and lethal potential of intermediate range exposures compared to household range exposures (0-220 V).

The end of the line: The relationship between New York City's subway system and residential class structure

NASA Astrophysics Data System (ADS)

Rhindress, Mindy

Public money is necessary to build and maintain this country's vast network of mass transit systems and highways. Thus you would expect class equity in choices of infrastructure location, types of projects and pricing. However, the influence of commercial interests appears to create a contradictory effect, and may negatively influence the settlement patterns where transit serves. New York City and its subway system offered the perfect case study by which to examine the before and after effects of mass transit introduction given the enormous size of the transit system and the grand development of New York City that appeared to occur simultaneous to subway inauguration. The main objective of this study was to determine the relationship between the growth of the New York City subway system and the establishment of class structure in residential patterns. Regional census data covering the first 16-year period of the subway's development was examined along with geographic statistics on subway line expansion and station openings. GIS (Geographic Information Systems) maps were used to illustrate the development of living spaces as a function of subway introduction into communities, and several Indices were computed to demonstrate the population growth and class disparity. The results revealed that the early years of transit development were entrepreneurial efforts coordinated by business interests. This led to transit first providing significant benefits mostly to the middle and upper classes, giving them a reasonable means by which to escape horrible tenement living conditions while turning a profit at the same time. Thus new settlements were stratified by class almost immediately after introduction. The cycle continued until years later when the automobile was introduced and the once expensive and luxurious, but now more reasonably priced and just functional, public transit system finally befit the population much lower on the socioeconomic scale. Class divisions still existed, but the subway's influence on this stratification decreased. The outcome of this study can provide important direction for new transportation projects that access public money by establishing guidelines to monitor business interests in new transit systems, while ensuring a fair pricing and land use policy.

The association between psychiatric disorders and work-related problems among subway drivers in Korea.

PubMed

Kim, Se-Eun; Kim, Hyoung-Ryoul; Park, Jong-Ik; Lee, Hae Woo; Lee, Jongin; Byun, Junsu; Yim, Hyeon Woo

2014-01-01

This study aimed to find the prevalence and occupational risk factors for major psychiatric disorders among subway drivers in South Korea. Of all 998 current subway drivers, 995 participated in this study. The Korean version of the Composite International Diagnostic Interview (K-CIDI 2.1) was administered by trained interviewers to diagnose psychiatric disorders in all participants. The questions on socio-demographic characteristics and working conditions included some questions related to a person under train (PUT) experience and work-related problems. One-year prevalence and lifetime prevalence of major depressive disorder (MDD), post-traumatic stress disorder (PTSD), and panic disorder were diagnosed through the interview. The standardized prevalence ratios (SPRs) of these three disorders were calculated in the sample of subway drivers using the 2011 Korean National Epidemiologic Survey data as a basis. Multiple logistic regressions were performed to determine the association between work-related factors and the prevalence of the psychiatric disorders. The standardized prevalence ratios (SPRs) for a 1-year prevalence of MDD and PTSD among subway drivers were 1.1 (95% CI 0.7-1.7) and 5.6 (95% CI 3.1-8.8), respectively. Conflict with passengers was significantly associated with an increased risk for both MDD and PTSD in 1-year and in lifetime prevalence. Experiencing a sudden stop due to an emergency bell increased the risk of the lifetime prevalence of MDD (OR 2.61, 95% CI 1.14-6.97) and PTSD (OR 7.53, 95% CI 1.77-32.02). The risk of PTSD significantly increased among drivers who once experienced a near accident in terms of both the 1-year prevalence (OR 8.81, 95% CI 1.96-39.3) and the lifetime prevalence (OR 6.36, 95% CI 2.40-16.90). PTSD and panic disorder were more prevalent among subway drivers than in the general population. We found that having a conflict with passengers, a near accident, and a breakdown while driving can be risk factors for psychiatric disorders among subway drivers. Therefore, a prompt and sensitive approach should be introduced for these high risk groups within the subway company.

Monitoring Ground Deformation of Subway Area during the Construction Based on the Method of Multi-Temporal Coherent Targets Analysis

NASA Astrophysics Data System (ADS)

Zhang, L.; Wu, J.; Zhao, J.; Yuan, M.

2018-04-01

Multi-temporal coherent targets analysis is a high-precision and high-spatial-resolution monitoring method for urban surface deformation based on Differential Synthetic Aperture Radar (DInSAR), and has been successfully applied to measure land subsidence, landslide and strain accumulation caused by fault movement and so on. In this paper, the multi-temporal coherent targets analysis is used to study the settlement of subway area during the period of subway construction. The eastern extension of Shanghai Metro Line. 2 is taking as an example to study the subway settlement during the construction period. The eastern extension of Shanghai Metro Line. 2 starts from Longyang Road and ends at Pudong airport. Its length is 29.9 kilometers from east to west and it is a key transportation line to the Pudong Airport. 17 PalSAR images during 2007 and 2010 are applied to analyze and invert the settlement of the buildings nearby the subway based on the multi-temporal coherent targets analysis. But there are three significant deformation areas nearby the Line 2 between 2007 and 2010, with maximum subsidence rate up to 30 mm/y in LOS. The settlement near the Longyang Road station and Chuansha Town are both caused by newly construction and city expansion. The deformation of the coastal dikes suffer from heavy settlement and the rate is up to -30 mm/y. In general, the area close to the subway line is relatively stable during the construction period.

Characterisation of nano- and micron-sized airborne and collected subway particles, a multi-analytical approach.

PubMed

Midander, Klara; Elihn, Karine; Wallén, Anna; Belova, Lyuba; Karlsson, Anna-Karin Borg; Wallinder, Inger Odnevall

2012-06-15

Continuous daily measurements of airborne particles were conducted during specific periods at an underground platform within the subway system of the city center of Stockholm, Sweden. Main emphasis was placed on number concentration, particle size distribution, soot content (analyzed as elemental and black carbon) and surface area concentration. Conventional measurements of mass concentrations were conducted in parallel as well as analysis of particle morphology, bulk- and surface composition. In addition, the presence of volatile and semi volatile organic compounds within freshly collected particle fractions of PM(10) and PM(2.5) were investigated and grouped according to functional groups. Similar periodic measurements were conducted at street level for comparison. The investigation clearly demonstrates a large dominance in number concentration of airborne nano-sized particles compared to coarse particles in the subway. Out of a mean particle number concentration of 12000 particles/cm(3) (7500 to 20000 particles/cm(3)), only 190 particles/cm(3) were larger than 250 nm. Soot particles from diesel exhaust, and metal-containing particles, primarily iron, were observed in the subway aerosol. Unique measurements on freshly collected subway particle size fractions of PM(10) and PM(2.5) identified several volatile and semi-volatile organic compounds, the presence of carcinogenic aromatic compounds and traces of flame retardants. This interdisciplinary and multi-analytical investigation aims to provide an improved understanding of reported adverse health effects induced by subway aerosols. Copyright © 2012 Elsevier B.V. All rights reserved.

Chemical characterization of outdoor and subway fine (PM(2.5-1.0)) and coarse (PM(10-2.5)) particulate matter in Seoul (Korea) by computer-controlled scanning electron microscopy (CCSEM).

PubMed

Byeon, Sang-Hoon; Willis, Robert; Peters, Thomas M

2015-02-13

Outdoor and indoor (subway) samples were collected by passive sampling in urban Seoul (Korea) and analyzed with computer-controlled scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (CCSEM-EDX). Soil/road dust particles accounted for 42%-60% (by weight) of fine particulate matter larger than 1 µm (PM(2.5-1.0)) in outdoor samples and 18% of PM2.5-1.0 in subway samples. Iron-containing particles accounted for only 3%-6% in outdoor samples but 69% in subway samples. Qualitatively similar results were found for coarse particulate matter (PM(10-2.5)) with soil/road dust particles dominating outdoor samples (66%-83%) and iron-containing particles contributing most to subway PM(10-2.5) (44%). As expected, soil/road dust particles comprised a greater mass fraction of PM(10-2.5) than PM(2.5-1.0). Also as expected, the mass fraction of iron-containing particles was substantially less in PM(10-2.5) than in PM(2.5-1.0). Results of this study are consistent with known emission sources in the area and with previous studies, which showed high concentrations of iron-containing particles in the subway compared to outdoor sites. Thus, passive sampling with CCSEM-EDX offers an inexpensive means to assess PM(2.5-1.0) and PM(10-2.5) simultaneously and by composition at multiple locations.

Scaling in Transportation Networks

PubMed Central

Louf, Rémi; Roth, Camille; Barthelemy, Marc

2014-01-01

Subway systems span most large cities, and railway networks most countries in the world. These networks are fundamental in the development of countries and their cities, and it is therefore crucial to understand their formation and evolution. However, if the topological properties of these networks are fairly well understood, how they relate to population and socio-economical properties remains an open question. We propose here a general coarse-grained approach, based on a cost-benefit analysis that accounts for the scaling properties of the main quantities characterizing these systems (the number of stations, the total length, and the ridership) with the substrate's population, area and wealth. More precisely, we show that the length, number of stations and ridership of subways and rail networks can be estimated knowing the area, population and wealth of the underlying region. These predictions are in good agreement with data gathered for about subway systems and more than railway networks in the world. We also show that train networks and subway systems can be described within the same framework, but with a fundamental difference: while the interstation distance seems to be constant and determined by the typical walking distance for subways, the interstation distance for railways scales with the number of stations. PMID:25029528

24. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., ...

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

24. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 81.69. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

26. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., ...

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

26. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 81.69. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

25. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., ...

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

25. Elevated SEPTA subway Bridge crossing NEC. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 81.69. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

77 FR 17051 - Environmental Impacts Statements; Notice of Availability

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-23

..., Contact: Tina Orcutt 410-962-4290. EIS No. 20120072, Final EIS, FTA, CA, Westside Subway Extension Transit Corridor Project, Extension of the Existing Metro Purple Line and Metro Red Line Heavy Rail Subway, Los...

Chemical speciation of size-segregated floor dusts and airborne magnetic particles collected at underground subway stations in Seoul, Korea.

PubMed

Jung, Hae-Jin; Kim, BoWha; Malek, Md Abdul; Koo, Yong Sung; Jung, Jong Hoon; Son, Youn-Suk; Kim, Jo-Chun; Kim, HyeKyoung; Ro, Chul-Un

2012-04-30

Previous studies have reported the major chemical species of underground subway particles to be Fe-containing species that are generated from wear and friction processes at rail-wheel-brake and catenaries-pantographs interfaces. To examine chemical composition of Fe-containing particles in more details, floor dusts were collected at five sampling locations of an underground subway station. Size-segregated floor dusts were separated into magnetic and non-magnetic fractions using a permanent magnet. Using X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDX), iron metal, which is relatively harmless, was found to be the dominating chemical species in the floor dusts of the <25 μm size fractions with minor fractions of Mg, Al, Si, Ca, S, and C. From SEM analysis, the floor dusts of the <25 μm size fractions collected on railroad ties appeared to be smaller than 10 μm, indicating that their characteristics should somewhat reflect the characteristics of airborne particles in the tunnel and the platform. As most floor dusts are magnetic, PM levels at underground subway stations can be controlled by removing magnetic indoor particles using magnets. In addition, airborne subway particles, most of which were smaller than 10 μm, were collected using permanent magnets at two underground subway stations, namely Jegi and Yangjae stations, in Seoul, Korea. XRD and SEM/EDX analyses showed that most of the magnetic aerosol particles collected at Jegi station was iron metal, whereas those at Yangjae station contained a small amount of Fe mixed with Na, Mg, Al, Si, S, Ca, and C. The difference in composition of the Fe-containing particles between the two subway stations was attributed to the different ballast tracks used. Copyright © 2012 Elsevier B.V. All rights reserved.

Indoor Air Quality in the Metro System in North Taiwan

PubMed Central

Chen, Ying-Yi; Sung, Fung-Chang; Chen, Mei-Lien; Mao, I-Fang; Lu, Chung-Yen

2016-01-01

Indoor air pollution is an increasing health concern, especially in enclosed environments such as underground subway stations because of increased global usage by urban populations. This study measured the indoor air quality of underground platforms at 10 metro stations of the Taipei Rapid Transit system (TRTS) in Taiwan, including humidity, temperature, carbon monoxide (CO), carbon dioxide (CO2), formaldehyde (HCHO), total volatile organic compounds (TVOCs), ozone (O3), airborne particulate matter (PM10 and PM2.5), bacteria and fungi. Results showed that the CO2, CO and HCHO levels met the stipulated standards as regulated by Taiwan’s Indoor Air Quality Management Act (TIAQMA). However, elevated PM10 and PM2.5 levels were measured at most stations. TVOCs and bacterial concentrations at some stations measured in summer were higher than the regulated standards stipulated by Taiwan’s Environmental Protection Administration. Further studies should be conducted to reduce particulate matters, TVOCs and bacteria in the air of subway stations. PMID:27918460

Environmental problems caused by Istanbul subway excavation and suggestions for remediation

NASA Astrophysics Data System (ADS)

Ocak, Ibrahim

2009-10-01

Many environmental problems caused by subway excavations have inevitably become an important point in city life. These problems can be categorized as transporting and stocking of excavated material, traffic jams, noise, vibrations, piles of dust mud and lack of supplies. Although these problems cause many difficulties, the most pressing for a big city like Istanbul is excavation, since other listed difficulties result from it. Moreover, these problems are environmentally and regionally restricted to the period over which construction projects are underway and disappear when construction is finished. Currently, in Istanbul, there are nine subway construction projects in operation, covering approximately 73 km in length; over 200 km to be constructed in the near future. The amount of material excavated from ongoing construction projects covers approximately 12 million m3. In this study, problems—primarily, the problem with excavation waste (EW)—caused by subway excavation are analyzed and suggestions for remediation are offered.

Subway train-related fatalities in New York City: accident versus suicide.

PubMed

Lin, Peter T; Gill, James R

2009-11-01

We examined the characteristics of subway train-related fatalities in New York City between Jan. 1, 2003 and May 31, 2007 in order to determine which factors are useful in differentiating accident from suicide. Subway train-related deaths with homicide and undetermined manners also are included. During this period, there were 211 subway train-related fatalities. The manners of death were: suicide (n = 111), accident (n = 76), undetermined (n = 20), and homicide (n = 4). The causes of death were blunt trauma (n = 206) and electrocution (n = 5). Torso transection and extremity amputation were more frequent in suicides. Antidepressant medications were more frequently detected in suicides, whereas cocaine and ethanol were more frequent in accidents. However, autopsy findings should be weighed in the context of the entire evaluation along with other circumstantial and investigative findings. In unwitnessed deaths where additional information is unavailable or discrepant, the most appropriate manner of death usually is undetermined.

Asthmatics exhibit altered oxylipin profiles compared to healthy individuals after subway air exposure.

PubMed

Lundström, Susanna L; Levänen, Bettina; Nording, Malin; Klepczynska-Nyström, Anna; Sköld, Magnus; Haeggström, Jesper Z; Grunewald, Johan; Svartengren, Magnus; Hammock, Bruce D; Larsson, Britt-Marie; Eklund, Anders; Wheelock, Åsa M; Wheelock, Craig E

2011-01-01

Asthma is a chronic inflammatory lung disease that causes significant morbidity and mortality worldwide. Air pollutants such as particulate matter (PM) and oxidants are important factors in causing exacerbations in asthmatics, and the source and composition of pollutants greatly affects pathological implications. This randomized crossover study investigated responses of the respiratory system to Stockholm subway air in asthmatics and healthy individuals. Eicosanoids and other oxylipins were quantified in the distal lung to provide a measure of shifts in lipid mediators in association with exposure to subway air relative to ambient air. Sixty-four oxylipins representing the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (CYP) metabolic pathways were screened using liquid chromatography-tandem mass spectrometry (LC-MS/MS) of bronchoalveolar lavage (BAL)-fluid. Validations through immunocytochemistry staining of BAL-cells were performed for 15-LOX-1, COX-1, COX-2 and peroxisome proliferator-activated receptor gamma (PPARγ). Multivariate statistics were employed to interrogate acquired oxylipin and immunocytochemistry data in combination with patient clinical information. Asthmatics and healthy individuals exhibited divergent oxylipin profiles following exposure to ambient and subway air. Significant changes were observed in 8 metabolites of linoleic- and α-linolenic acid synthesized via the 15-LOX pathway, and of the COX product prostaglandin E(2) (PGE(2)). Oxylipin levels were increased in healthy individuals following exposure to subway air, whereas asthmatics evidenced decreases or no change. Several of the altered oxylipins have known or suspected bronchoprotective or anti-inflammatory effects, suggesting a possible reduced anti-inflammatory response in asthmatics following exposure to subway air. These observations may have ramifications for sensitive subpopulations in urban areas.

Chemical Characterization of Outdoor and Subway Fine (PM2.5–1.0) and Coarse (PM10–2.5) Particulate Matter in Seoul (Korea) by Computer-Controlled Scanning Electron Microscopy (CCSEM)

PubMed Central

Byeon, Sang-Hoon; Willis, Robert; Peters, Thomas M.

2015-01-01

Outdoor and indoor (subway) samples were collected by passive sampling in urban Seoul (Korea) and analyzed with computer-controlled scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (CCSEM-EDX). Soil/road dust particles accounted for 42%–60% (by weight) of fine particulate matter larger than 1 µm (PM2.5–1.0) in outdoor samples and 18% of PM2.5–1.0 in subway samples. Iron-containing particles accounted for only 3%–6% in outdoor samples but 69% in subway samples. Qualitatively similar results were found for coarse particulate matter (PM10–2.5) with soil/road dust particles dominating outdoor samples (66%–83%) and iron-containing particles contributing most to subway PM10–2.5 (44%). As expected, soil/road dust particles comprised a greater mass fraction of PM10–2.5 than PM2.5–1.0. Also as expected, the mass fraction of iron-containing particles was substantially less in PM10–2.5 than in PM2.5–1.0. Results of this study are consistent with known emission sources in the area and with previous studies, which showed high concentrations of iron-containing particles in the subway compared to outdoor sites. Thus, passive sampling with CCSEM-EDX offers an inexpensive means to assess PM2.5–1.0 and PM10-2.5 simultaneously and by composition at multiple locations. PMID:25689348

Genotoxic effects and oxidative stress induced by organic extracts of particulate matter(PM 10)collected from a subway tunnel in Seoul, Korea.

PubMed

Jung, Mi Hyun; Kim, Ha Ryong; Park, Yong Joo; Park, Duck Shin; Chung, Kyu Hyuck; Oh, Seung Min

2012-12-12

Particulate matter (PM) has become an important health risk factor in our society. PM can easily deposit in the bronchi and lungs, causing diverse diseases such as respiratory infections, lung cancers and cardiovascular diseases. In recent days, more and more toxicological studies have been dealing with air particles in distinctive areas including industrial areas, transportation sites, or indoors. Studies on subway PM in particular, have been recognizing PM as an important health risk factor because many people use subways as a major mode of public transportation (4 million people a day in Korea). The main aim of the present study was to evaluate the genotoxic effects of organic extract (OE) of subway PM10 and potential attribution of PAHs to these effects. Particles were collected in the subway tunnel at Kil-eum station(Line 4) for one month and then extracted with Dichloromethane (DCM). Chinese Hamster Ovary cells(CHO-K1) and human normal bronchial cells (BEAS-2B) were exposed to OE, and MN and Comet assays were conducted to analyze the genotoxicity. The results showed that OE increased DNA or chromosome damages in both cell lines. In the modified Comet assay and MN assay with free radical scavengers, we confirmed that the genotoxic effect of OE was partially due to the oxidative damage on DNA. DCFHD Aassay also indicated that OE induced ROS generation in BEAS-2B cells. PAHs [benzo(a)anthracene,benzo(k)fluoranthrene, etc.], the most well-known carcinogens in polluted air, were detected in Kil-eum PM10. In conclusion, our findings confirmed that OE of subway PM10 has genotoxic effects on normal human lung cells, and oxidative stress could be one of the major mechanisms of these genotoxic effects.In addition, some genotoxic and carcinogenic PAHs were detected in OE by GC/MS/MS, even though PAHs level was not enough to increase CYP1A1 gene. Therefore, we suggest that additive or synergistic effects by unidentified chemicals as well as PAHs contained in OE of subway PM10 may induce genotoxic effects and further researches are needed to identify the genotoxic compounds in subway PM.

Tunnel and Station Cost Methodology : Mined Tunnels

DOT National Transportation Integrated Search

1983-01-01

The main objective of this study was to develop a model for estimating the cost of subway station and tunnel construction. This report describes a cost estimating methodology for subway tunnels that can be used by planners, designers, owners, and gov...

Tunnel and Station Cost Methodology Volume II: Stations

DOT National Transportation Integrated Search

1981-01-01

The main objective of this study was to develop a model for estimating the cost of subway station and tunnel construction. This report describes a cost estimating methodology for subway tunnels that can be used by planners, designers, owners, and gov...

Study on the Application of the Kent Index Method on the Risk Assessment of Disastrous Accidents in Subway Engineering

PubMed Central

Lu, Hao; Wang, Mingyang; Yang, Baohuai; Rong, Xiaoli

2013-01-01

With the development of subway engineering, according to uncertain factors and serious accidents involved in the construction of subways, implementing risk assessment is necessary and may bring a number of benefits for construction safety. The Kent index method extensively used in pipeline construction is improved to make risk assessment much more practical for the risk assessment of disastrous accidents in subway engineering. In the improved method, the indexes are divided into four categories, namely, basic, design, construction, and consequence indexes. In this study, a risk assessment model containing four kinds of indexes is provided. Three kinds of risk occurrence modes are listed. The probability index model which considers the relativity of the indexes is established according to the risk occurrence modes. The model provides the risk assessment process through the fault tree method and has been applied in the risk assessment of Nanjing subway's river-crossing tunnel construction. Based on the assessment results, the builders were informed of what risks should be noticed and what they should do to avoid the risks. The need for further research is discussed. Overall, this method may provide a tool for the builders, and improve the safety of the construction. PMID:23710136

Commuter exposure to particulate matter and particle-bound PAHs in three transportation modes in Beijing, China.

PubMed

Yan, Caiqing; Zheng, Mei; Yang, Qiaoyun; Zhang, Qunfang; Qiu, Xinghua; Zhang, Yanjun; Fu, Huaiyu; Li, Xiaoying; Zhu, Tong; Zhu, Yifang

2015-09-01

Exposure to fine and ultrafine particles as well as particulate polycyclic aromatic hydrocarbons (PAHs) by commuters in three transportation modes (walking, subway and bus) were examined in December 2011 in Beijing, China. During the study period, real-time measured median PM2.5 mass concentration (PMC) for walking, riding buses and taking the subway were 26.7, 32.9 and 56.9 μg m(-3), respectively, and particle number concentrations (PNC) were 1.1 × 10(4), 1.0 × 10(4) and 2.2 × 10(4) cm(-3). Commuters were exposed to higher PNC in air-conditioned buses and aboveground-railway, but higher PMC in underground-subway compared to aboveground-railway. PNC in roadway modes (bus and walking) peaked at noon, but was lower during traffic rush hours, negatively correlated with PMC. Toxic potential of particulate-PAHs estimated based on benzo(a)pyrene toxic equivalents (BaP TEQs) showed that walking pedestrians were subjected to higher BaP TEQs than bus (2.7-fold) and subway (3.6-fold) commuters, though the highest PMC and PNC were observed in subway. Copyright © 2015 Elsevier Ltd. All rights reserved.

Origin of polycyclic aromatic hydrocarbons and other organic pollutants in the air particles of subway stations in Barcelona.

PubMed

van Drooge, Barend L; Prats, Raimon M; Reche, Cristina; Minguillón, MariCruz; Querol, Xavier; Grimalt, Joan O; Moreno, Teresa

2018-06-09

Underground subways transport large numbers of citizens in big cities, which must breathe air with limited ventilation. These atmospheric conditions may enhance the concentration of air pollutants from both outdoor and indoor air. The influence of ventilation conditions and maintenance activities on the concentrations of air pollutants have been studied. Particulate matter with aerodynamic diameter smaller than 2.5 μm (PM 2.5 ) in indoor air was sampled in ten platforms of nine subway stations of the metropolitan area of Barcelona in 2015 and 2016. These particles were analyzed for polycyclic aromatic hydrocarbons (PAH) and organic tracer compounds. The concentrations of PAH were in the range of the street air levels with higher PAH values in the colder period. No influence of nighttime maintenance activities was observed on the platform air quality during daytime. Source apportionment analysis using the concentrations of hopanes, nicotine and levoglucosan as molecular tracer compounds showed that 75% of the detected PAH at the platforms have an outdoor PM origin. The modern subway stations, with advanced ventilation and platform screen doors that separate the subway system from the platform, showed lowest PAH and PM concentrations. Copyright © 2018. Published by Elsevier B.V.

Particulate matter (PM) concentrations in underground and ground-level rail systems of the Los Angeles Metro

NASA Astrophysics Data System (ADS)

Kam, Winnie; Cheung, Kalam; Daher, Nancy; Sioutas, Constantinos

2011-03-01

Elevated concentrations of particulate matter (PM) have been found in a number of worldwide underground transit systems, with major implications regarding exposure of commuters to PM and its associated health effects. An extensive sampling campaign was conducted in May-August 2010 to measure PM concentrations in two lines of the Los Angeles Metro system - an underground subway line (Metro red line) and a ground-level light-rail line (Metro gold line). The campaign goals were to: 1) determine personal PM exposure of commuters of both lines, and 2) measure and compare PM concentrations at station platforms and inside the train. Considering that a commuter typically spent 75% of time inside the train and 25% of time waiting at a station, subway commuters were exposed on average to PM 10 and PM 2.5 concentrations that were 1.9 and 1.8 times greater than the light-rail commuters. The average PM 10 concentrations for the subway line at station platforms and inside the train were 78.0 μg m -3 and 31.5 μg m -3, respectively; for the light-rail line, corresponding PM 10 concentrations were 38.2 μg m -3 and 16.2 μg m -3. Regression analysis demonstrated that personal exposure concentrations for the light-rail line are strongly associated with ambient PM levels ( R2 = 0.61), while PM concentrations for the subway line are less influenced by ambient conditions ( R2 = 0.38) and have a relatively stable background level of about 21 μg m -3. Our findings suggest that local emissions (i.e., vehicular traffic, road dust) are the main source of airborne PM for the light-rail line. The subway line, on the other hand, has an additional source of PM, most likely generated from the daily operation of trains. Strong inter-correlation of PM 10 between the train and station microenvironments shows that airborne PM at stations are the main source of PM inside the trains for both lines ( R2 = 0.91 and 0.81 for subway and light-rail line, respectively). In addition, PM 2.5 and coarse PM (PM 10-2.5) are also strongly correlated for the subway line ( R2 = 0.89) and the light-rail line ( R2 = 0.52-0.92), suggesting that PM 2.5 and coarse PM originate from a common source. Finally, in comparison to worldwide subway systems, the L.A. Metro system is relatively 'clean'. Since the system is comparatively new (in operation since 1993), its ventilation system and braking technology are probably more efficient and more advanced than older subway systems.

A demonstrator for an integrated subway protection system

NASA Astrophysics Data System (ADS)

Detoma, E.; Capetti, P.; Casati, G.; Billington, S.

2008-04-01

In 2006 SEPA has carried on the installation and tests of a demonstrator for an integrated subway protection system at a new subway station in the Naples, Italy) metropolitan area. Protection of a subway system is a difficult task given the amount of passengers transported every day. The demonstrator has been limited to non-intrusive detection techniques not to impair the passenger flow into the station. The demonstrator integrates several technologies and products that have been developed by SEPA or are already available on the market (MKS Instruments,...). The main purpose is to provide detection capabilities for attempts to introduce radioactive substances in the subway station, in order to foil possible attempts to place a dirty bomb, and threat detection and identification following release of chemical agents. The system integrates additional sensors such as video surveillance cameras and air flow sensing to complement the basic sensors suite. The need to protect sensitive installations such as subway stations has been highlighted by the series of terroristics actions carried out in recent years in the subway in London. However, given the number of passengers of a metro system, it is impossible to propose security techniques operating in ways similar to the screening of passengers in airports. Passengers screening and threat detection and identification must be quick, non-intrusive and capable of screening a large number of passengers to be applicable to mass transit systems. In 2005 SEPA, a small company operating in the field of trains video-surveillance systems and radiation detectors, started developing an integrated system to provide a comprehensive protection to subway stations, based on ready available or off-the-shelf components in order to quickly develop a reliable system with available technology. We ruled out at the beginning any new development in order to speed up the fielding of the system in less than one year. The system was developed with commercial sensors and deployed in a new station of the Naples metropolitan transit system in Mugnano. The station was particularly suitable for the demonstration since it is a new station that includes air venting control, water barriers (for fire and smoke containment) and a complete SCADA system to integrate technical and video surveillance operations. In order to protect the subway, we tackled four basic technologies, all readily available in-house or on the market: - radiation detection, to detect the introduction in the station of radionuclides, that may be dispersed by conventional explosive (a "dirty" bomb); - chemical agents detection and identification (after release), complemented with air speed and velocity sensors to estimate, track and predict the contamination plume; - video surveillance, integrated with the SCADA system and already available in the station.

Communications Based Train Control (CBTC) Before and After Cost Study

DOT National Transportation Integrated Search

2011-03-01

San Francisco Municipal Railway (Muni) undertook a retrofit of a fixed-block signaling system with a communications-based train control (CBTC) system in the subway portion of their light rail system (Muni Metro subway) in 1998. This report presents t...

Asthmatics Exhibit Altered Oxylipin Profiles Compared to Healthy Individuals after Subway Air Exposure

PubMed Central

Nording, Malin; Klepczynska-Nyström, Anna; Sköld, Magnus; Haeggström, Jesper Z.; Grunewald, Johan; Svartengren, Magnus; Hammock, Bruce D.; Larsson, Britt-Marie; Eklund, Anders; Wheelock, Åsa M.; Wheelock, Craig E.

2011-01-01

Background Asthma is a chronic inflammatory lung disease that causes significant morbidity and mortality worldwide. Air pollutants such as particulate matter (PM) and oxidants are important factors in causing exacerbations in asthmatics, and the source and composition of pollutants greatly affects pathological implications. Objectives This randomized crossover study investigated responses of the respiratory system to Stockholm subway air in asthmatics and healthy individuals. Eicosanoids and other oxylipins were quantified in the distal lung to provide a measure of shifts in lipid mediators in association with exposure to subway air relative to ambient air. Methods Sixty-four oxylipins representing the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (CYP) metabolic pathways were screened using liquid chromatography-tandem mass spectrometry (LC-MS/MS) of bronchoalveolar lavage (BAL)-fluid. Validations through immunocytochemistry staining of BAL-cells were performed for 15-LOX-1, COX-1, COX-2 and peroxisome proliferator-activated receptor gamma (PPARγ). Multivariate statistics were employed to interrogate acquired oxylipin and immunocytochemistry data in combination with patient clinical information. Results Asthmatics and healthy individuals exhibited divergent oxylipin profiles following exposure to ambient and subway air. Significant changes were observed in 8 metabolites of linoleic- and α-linolenic acid synthesized via the 15-LOX pathway, and of the COX product prostaglandin E2 (PGE2). Oxylipin levels were increased in healthy individuals following exposure to subway air, whereas asthmatics evidenced decreases or no change. Conclusions Several of the altered oxylipins have known or suspected bronchoprotective or anti-inflammatory effects, suggesting a possible reduced anti-inflammatory response in asthmatics following exposure to subway air. These observations may have ramifications for sensitive subpopulations in urban areas. PMID:21897859

Constructing a generalized network design model to study air distribution in ventilation networks in subway with a single-track tunnel

NASA Astrophysics Data System (ADS)

Lugin, IV

2018-03-01

In focus are the features of construction of the generalized design model for the network method to study air distribution in ventilation system in subway with the single-track tunnel. The generalizations, assumptions and simplifications included in the model are specified. The air distribution is calculated with regard to the influence of topology and air resistances of the ventilation network sections. The author studies two variants of the subway line: half-open and closed with dead end on the both sides. It is found that the total air exchange at a subway station depends on the station location within the line. The operating mode of fans remains unaltered in this case. The article shows that elimination of air leakage in the station ventilation room allows an increase in the air flow rate by 7–8% at the same energy consumption by fans. The influence of the stop of a train in the tunnel on the air distribution is illustrated.

Back disorders and health problems among subway train operators exposed to whole-body vibration.

PubMed

Johanning, E

1991-12-01

Back disease associated with whole-body vibration has not been evaluated for subway train operators. A recent study demonstrated that this group is exposed to whole-body vibration at levels above the international standard. To investigate this risk further, a self-administered questionnaire survey was conducted among subway train operators (N = 492) and a similar reference group (N = 92). The operators had a higher prevalence than the referents in all aspects of back problems, particularly for cervical and lower back pain. In a multiple logistic regression model, the odds ratio for sciatic pain among subway train operators was 3.9 (95% CI 1.7-8.6); the operators also had a higher risk of hearing-related problems (odds ratio 3.2, 95% CI 0.6-17.4) and of gastrointestinal problems (odds ratio 1.6, 95% CI 1.1-2.5). Although a cumulative dose-response relationship could not be statistically demonstrated, the findings appear to be related to exposure to whole-body vibration and inadequate ergonomic conditions.

Weighted complex network analysis of the Beijing subway system: Train and passenger flows

NASA Astrophysics Data System (ADS)

Feng, Jia; Li, Xiamiao; Mao, Baohua; Xu, Qi; Bai, Yun

2017-05-01

In recent years, complex network theory has become an important approach to the study of the structure and dynamics of traffic networks. However, because traffic data is difficult to collect, previous studies have usually focused on the physical topology of subway systems, whereas few studies have considered the characteristics of traffic flows through the network. Therefore, in this paper, we present a multi-layer model to analyze traffic flow patterns in subway networks, based on trip data and an operation timetable obtained from the Beijing Subway System. We characterize the patterns in terms of the spatiotemporal flow size distributions of both the train flow network and the passenger flow network. In addition, we describe the essential interactions between these two networks based on statistical analyses. The results of this study suggest that layered models of transportation systems can elucidate fundamental differences between the coexisting traffic flows and can also clarify the mechanism that causes these differences.

Biological effects of particles from the paris subway system.

PubMed

Bachoual, Rafik; Boczkowski, Jorge; Goven, Delphine; Amara, Nadia; Tabet, Lyes; On, Dinhill; Leçon-Malas, Véronique; Aubier, Michel; Lanone, Sophie

2007-10-01

Particulate matter (PM) from atmospheric pollution can easily deposit in the lungs and induce recruitment of inflammatory cells, a source of inflammatory cytokines, oxidants, and matrix metalloproteases (MMPs), which are important players in lung structural homeostasis. In many large cities, the subway system is a potent source of PM emission, but little is known about the biological effects of PM from this source. We performed a comprehensive study to evaluate the biological effects of PM sampled at two sites (RER and Metro) in the Paris subway system. Murine macrophages (RAW 264.7) and C57Bl/6 mice, respectively, were exposed to 0.01-10 microg/cm2 and 5-100 microg/mouse subway PM or reference materials [carbon black (CB), titanium dioxide (TiO2), or diesel exhaust particles (DEPs)]. We analyzed cell viability, production of cellular and lung proinflammatory cytokines [tumor necrosis factor alpha (TNFalpha), macrophage inflammatory protein (MIP-2), KC (the murin analog of interleukin-8), and granulocyte macrophage-colony stimulating factor (GM-CSF)], and mRNA or protein expression of MMP-2, -9, and -12 and heme oxygenase-1 (HO-1). Deferoxamine and polymixin B were used to evaluate the roles of iron and endotoxin, respectively. Noncytotoxic concentrations of subway PM (but not CB, TiO2, or DEPs) induced a time- and dose-dependent increase in TNFalpha and MIP-2 production by RAW 264.7 cells, in a manner involving, at least in part, PM iron content (34% inhibition of TNF production 8 h after stimulation of RAW 264.7 cells with 10 microg/cm2 RER particles pretreated with deferoxamine). Similar increased cytokine production was transiently observed in vivo in mice and was accompanied by an increased neutrophil cellularity of bronchoalveolar lavage (84.83+/-0.98% of polymorphonuclear neutrophils for RER-treated mice after 24 h vs 7.33+/-0.99% for vehicle-treated animals). Subway PM induced an increased expression of MMP-12 and HO-1 both in vitro and in vivo. PM from the Paris subway system has transient biological effects. Further studies are needed to better understand the pathophysiological implications of these findings.

Purchasing Behavior and Calorie Information at Fast-Food Chains in New York City, 2007

PubMed Central

Bassett, Mary T.; Dumanovsky, Tamara; Huang, Christina; Silver, Lynn D.; Young, Candace; Nonas, Cathy; Matte, Thomas D.; Chideya, Sekai; Frieden, Thomas R.

2008-01-01

We surveyed 7318 customers from 275 randomly selected restaurants of 11 fast food chains. Participants purchased a mean of 827 calories, with 34% purchasing 1000 calories or more. Unlike other chains, Subway posted calorie information at point of purchase and its patrons more often reported seeing calorie infomation than patrons of other chains (32% vs 4%; P<.001); Subway patrons who saw calorie information purchased 52 fewer calories than did other Subway patrons (P<.01). Fast-food chains should display calorie information prominently at point of purchase, where it can be seen and used to inform purchases. PMID:18556597

Whole-body vibration exposure: a comprehensive field study.

PubMed

Ozkaya, N; Willems, B; Goldsheyder, D

1994-12-01

A comprehensive field study investigated whole-body vibration exposure levels experienced by the train operators of a large metropolitan subway system. The purposes of the study were to measure mechanical vibrations transmitted to the seated train operators, to calculate daily whole-body vibration exposure levels, and to compare these levels with maximum acceptable exposure levels recommended by the international standard on whole-body vibration (ISO 2631). The study also sought to identify factors that may influence mechanical vibrations transmitted to the operators and quantify their effects on the measured vibration levels. The study was carried out by dividing the subway system into subway lines, each line into southbound and northbound directions, and each direction into station-to-station observations. Triaxial measurements were made on all subway lines and for all car types used in the system. For each line, at least two round trips of data were collected. Time-weighted averages of the two sets of data were used for final presentation. A total of 48 round trips were made and more than 100 hours of vibration data was collected and analyzed. All phases of the study were carried out in accordance with the procedures outlined in ISO 2631. It was determined that 6 out of 20 subway lines had vibration levels higher than daily exposure limits recommended by ISO 2631. It was also determined that train speed was the most significant factor influencing vibration exposure levels.

Cycling for Transportation in Sao Paulo City: Associations with Bike Paths, Train and Subway Stations

PubMed Central

Barrozo, Ligia Vizeu; Cabral-Miranda, William; Cesar, Chester Luiz Galvão

2018-01-01

Cities that support cycling for transportation reap many public health benefits. However, the prevalence of this mode of transportation is low in Latin American countries and the association with facilities such as bike paths and train/subway stations have not been clarified. We conducted a cross-sectional analysis of the relationship between bike paths, train/subway stations and cycling for transportation in adults from the city of Sao Paulo. We used data from the Sao Paulo Health Survey (n = 3145). Cycling for transportation was evaluated by a questionnaire and bike paths and train/subway stations were geocoded using the geographic coordinates of the adults’ residential addresses in 1500-m buffers. We used multilevel logistic regression, taking account of clustering by census tract and households. The prevalence of cycling for transportation was low (5.1%), and was more prevalent in males, singles, those active in leisure time, and in people with bicycle ownership in their family. Cycling for transportation was associated with bike paths up to a distance of 500 m from residences (OR (Odds Ratio) = 2.54, 95% CI (Confidence interval) 1.16–5.54) and with the presence of train/subway stations for distances >500 m from residences (OR = 2.07, 95% CI 1.10–3.86). These results are important to support policies to improve cycling for transportation in megacities such as Sao Paulo. PMID:29561755

Oxidative potential of subway PM2.5

NASA Astrophysics Data System (ADS)

Moreno, Teresa; Kelly, Frank J.; Dunster, Chrissi; Oliete, Ana; Martins, Vânia; Reche, Cristina; Minguillón, Maria Cruz; Amato, Fulvio; Capdevila, Marta; de Miguel, Eladio; Querol, Xavier

2017-01-01

Air quality in subway systems is of interest not only because particulate matter (PM) concentrations can be high, but also because of the peculiarly metalliferous chemical character of the particles, most of which differ radically from those of outdoor ambient air. We report on the oxidative potential (OP) of PM2.5 samples collected in the Barcelona subway system in different types of stations. The PM chemical composition of these samples showed typically high concentrations of Fe, Total Carbon, Ba, Cu, Mn, Zn and Cr sourced from rail tracks, wheels, catenaries, brake pads and pantographs. Two toxicological indicators of oxidative activity, ascorbic acid (AA) oxidation (expressed as OPAA μg-1 or OPAA m-3) and glutathione (GSH) oxidation (expressed as OPGSH μg-1 or OPGSH m-3), showed low OP for all samples (compared with outdoor air) but considerable variation between stations (0.9-2.4 OPAA μg-1; 0.4-1.9 OPGSH μg-1). Results indicate that subway PM toxicity is not related to variations in PM2.5 concentrations produced by ventilation changes, tunnel works, or station design, but may be affected more by the presence of metallic trace elements such as Cu and Sb sourced from brakes and pantographs. The OP assays employed do not reveal toxic effects from the highly ferruginous component present in subway dust.

Cycling for Transportation in Sao Paulo City: Associations with Bike Paths, Train and Subway Stations.

PubMed

Florindo, Alex Antonio; Barrozo, Ligia Vizeu; Turrell, Gavin; Barbosa, João Paulo Dos Anjos Souza; Cabral-Miranda, William; Cesar, Chester Luiz Galvão; Goldbaum, Moisés

2018-03-21

Cities that support cycling for transportation reap many public health benefits. However, the prevalence of this mode of transportation is low in Latin American countries and the association with facilities such as bike paths and train/subway stations have not been clarified. We conducted a cross-sectional analysis of the relationship between bike paths, train/subway stations and cycling for transportation in adults from the city of Sao Paulo. We used data from the Sao Paulo Health Survey ( n = 3145). Cycling for transportation was evaluated by a questionnaire and bike paths and train/subway stations were geocoded using the geographic coordinates of the adults' residential addresses in 1500-m buffers. We used multilevel logistic regression, taking account of clustering by census tract and households. The prevalence of cycling for transportation was low (5.1%), and was more prevalent in males, singles, those active in leisure time, and in people with bicycle ownership in their family. Cycling for transportation was associated with bike paths up to a distance of 500 m from residences (OR (Odds Ratio) = 2.54, 95% CI (Confidence interval) 1.16-5.54) and with the presence of train/subway stations for distances >500 m from residences (OR = 2.07, 95% CI 1.10-3.86). These results are important to support policies to improve cycling for transportation in megacities such as Sao Paulo.

ScienceToGo.org: Using 'Ozzie the Ostrich' to Build Local Partnerships around Climate Change Learning

NASA Astrophysics Data System (ADS)

Lustick, D. S.; Lohmeier, J.; Chen, R. F.; Wilson, R.; Rabkin, D.; Thompson, S. R.

2015-12-01

How can an informal science learning project about climate change facilitate alliances among unlikely parties? We found a sweet spot of collaboration among private, public, and the non-profit sectors by borrowing strength and leveraging common interests. Using mass transit and out of home media, we created a diverse community around a learning campaign that starred an ostrich named "Ozzie." In 2013-14, ScienceToGo.org ran a series of 12 engaging posters and placards staring 'Ozzie the Ostrich' on the Massachusetts Bay Transit Authority's Red and Orange subway lines targeting a daily audience of 400,000+ riders. The curriculum was divided into three phases: reality, relevance, and hope. Phase I established the reality of climate change (3 months). Phase II helped T-riders appreciate the relevancy of climate change to the local environment of Boston (4 months). Phase III engaged Bostonians with an array of hopeful examples of how people, companies, and organizations are effectively creating a more sustainable future (5 months). The focus of this presentation will be on the relationships that emerged from the work that went into Phase III. Engaging urban populations with climate change science is a difficult challenge since cities seem so removed from the 'natural environment.' However, mass transit provides an inherent means of communicating environmental messages with a cross section of the urban population. Our team felt that any messaging curriculum for an urban subway system must complement the scary reality of a changing climate with hopeful solutions that exist for dealing with it effectively. Urban areas such as Boston must develop adaptation and mitigation strategies that will help them not only survive, but thrive in a changing environment. Making our audience aware of the amazing efforts in this area was the goal of Phase III. There were three parts to our efforts: the signage on the subway, above ground ostriches, and social events. During the presentation, we will describe ScienceToGo.org and explore the various theories that help explain why Phase III was successful at building alliances among more than three dozen diverse urban partners. Finally, we will conclude with some recommendations for how this work could improve and inform other urban informal science learning initiatives.

Concentrations and identification of culturable airborne fungi in underground stations of the Seoul metro.

PubMed

Hwang, Sung Ho; Jang, Soojin; Park, Wha Me; Park, Jae Bum

2016-10-01

The purpose of this study was to measure the culturable airborne fungi (CAF) concentrations in the underground subway stations of Seoul, Korea at two time points. This study measured the CAF concentrations in enclosed environments at 16 underground stations of the Seoul Metro in 2006 and 2013 and investigated the effects of various environmental factors, including the presence of platform screen doors, temperature, relative humidity, and number of passengers. CAF concentrations at the stations in 2006 were significantly higher than that at the same stations in 2013 (p < 0.001). Furthermore, there was a significant correlation between CAF concentration and relative humidity (r = 0.311, p < 0.05). Geotrichum and Penicillium were the predominant genera. The CAF concentrations in stations with an operating supply air were significantly higher than that in stations with no supply air (p < 0.001). Therefore, it is recommended that special attention be given to stations with clean supplied air to improve the indoor air quality of these subway stations.

Radon exposure assessment for underground workers: a case of Seoul Subway Police officers in Korea.

PubMed

Song, Myeong Han; Chang, Byung-Uck; Kim, Yongjae; Cho, Kun-Woo

2011-11-01

The objective of this study is the systematic and individual assessment of the annual effective dose due to inhaled radon for the Seoul Subway Police officers, Korea. The annual average radon concentrations were found to be in the range of 18.9-114 Bq·m(-3) in their workplaces. The total annual effective doses which may likely to be received on duty were assessed to be in the range of 0.41-1.64 mSv·y(-1). These were well below the recommended action level 10 mSv·y(-1) by ICRP. However, the effective doses were higher than subway station staff in Seoul, Korea.

Modification of the gravity model and application to the metropolitan Seoul subway system.

PubMed

Goh, Segun; Lee, Keumsook; Park, Jong Soo; Choi, M Y

2012-08-01

The Metropolitan Seoul Subway system is examined through the use of the gravity model. Exponents describing the power-law dependence on the time distance between stations are obtained, which reveals a universality for subway lines of the same topology. In the short (time) distance regime the number of passengers between stations does not grow with the decrease in the distance, thus deviating from the power-law behavior. It is found that such reduction in passengers is well described by the Hill function. Further, temporal fluctuations in the passenger flow data, fitted to the gravity model modified by the Hill function, are analyzed to reveal the Yule-type nature inherent in the structure of Seoul.

49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 9 2012-10-01 2012-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged...

49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 9 2011-10-01 2011-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged...

49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 9 2013-10-01 2013-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged...

49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 9 2014-10-01 2014-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged...

Saturday Subway Ride: A Report on the Initial Tryout.

ERIC Educational Resources Information Center

Quilling, Mary R.; And Others

"Saturday Subway Ride," a program designed to teach pupils creative thinking techniques and positive attitudes toward creative ideas, is a 92-page workbook in a story-exercise format. Secondary objectives for the product include improving verbal fluency and creative writing. Three classrooms 61 sixth graders and 34 fifth graders at two…

Suicide and Mass Urban Transit.

ERIC Educational Resources Information Center

Berman, Alan L., Ed.

1991-01-01

Presents case consultation in which consultants respond to issues of urban planning for mass transit (subway) system and how to maximize prevention of intentional injury within subway stations. Also asks what type of research study should be used and what type of data collected once system is operating. Case is discussed by Morton M. Silverman and…

[Further microbiological studies of the air in a newly built (under the pavement) section of the underground railway in Budapest].

PubMed

Szám, L; Vedres, I; Csatai, L; Nikodemusz, I

1983-04-01

In three subway stations, which are "sub-pavement" stations (Budapest), microbiological air analyses were simultaneously carried out by means of sedimentation and by the use of Krotow's impactor. In the course of the examinations, which lasted eight months, the following max. values were obtained on the agar plates: 78 colonies/dm2/h and 239 colonies/m3; the rates of incidence for pathogenic and indicator bacteria were 2.7 and 1.7 per 10 plates. The strongest airflow was 0.7 m/sec. These values were obtained at the "Nagy-várad tér" station, which forms a transition to the subway stations. The "stopper effect" was found to exist here as well, although not to such an extent as in the deep subway stations, but still more pronounced than in the other two "subpavement" stations "Esceri ut" and "Határ ut". The microbiological values are at any rate more favourable than in the subway stations dealt with in an earlier paper.

Assessment of noise exposure during commuting in the Madrid subway.

PubMed

Tabacchi, M; Pavón, I; Ausejo, M; Asensio, C; Recuero, M

2011-09-01

Because noise-induced hearing impairment is the result not only of occupational noise exposure but also of total daily noise exposure, it is important to take the non-occupational exposure of individuals (during commuting to and from their jobs, at home, and during recreational activities) into account. Mass transit is one of the main contributors to non-occupational noise exposure. We developed a new methodology to estimate a representative commuting noise exposure. The methodology was put into practice for the Madrid subway because of all Spanish subway systems it covers the highest percentage of worker journeys (22.6%). The results of the application highlight that, for Madrid subway passengers, noise exposure level normalized to a nominal 8 hr (L(Ex,8h-cj) ) depends strongly on the type of train, the presence of squealing noise, and the public address audio system, ranging from 68.6 dBA to 72.8 dBA. These values play an important role in a more complete evaluation of a relationship between noise dose and worker health response.

Network structure of subway passenger flows

NASA Astrophysics Data System (ADS)

Xu, Q.; Mao, B. H.; Bai, Y.

2016-03-01

The results of transportation infrastructure network analyses have been used to analyze complex networks in a topological context. However, most modeling approaches, including those based on complex network theory, do not fully account for real-life traffic patterns and may provide an incomplete view of network functions. This study utilizes trip data obtained from the Beijing Subway System to characterize individual passenger movement patterns. A directed weighted passenger flow network was constructed from the subway infrastructure network topology by incorporating trip data. The passenger flow networks exhibit several properties that can be characterized by power-law distributions based on flow size, and log-logistic distributions based on the fraction of boarding and departing passengers. The study also characterizes the temporal patterns of in-transit and waiting passengers and provides a hierarchical clustering structure for passenger flows. This hierarchical flow organization varies in the spatial domain. Ten cluster groups were identified, indicating a hierarchical urban polycentric structure composed of large concentrated flows at urban activity centers. These empirical findings provide insights regarding urban human mobility patterns within a large subway network.

Artificial Reefs in Motion: Legacy of changes and degradation at the Redbird Reef Site

NASA Astrophysics Data System (ADS)

Trembanis, A. C.; DuVal, C.; Peter, B.

2016-12-01

Artificial reefs are used for a variety of purposes at sites throughout the U.S. and around the globe, yet little, if any, long-term monitoring has been conducted with the goal of understanding inter-annual changes to the emplaced structures. Throughout the U.S. Mid-Atlantic region, several programs utilized retired subway cars as disposal structures to form artificial reefs. One such site, known as site 11, or "Redbird Reef", is located off the coast of Delaware and was at one time home to 997 former NYC subway cars. Opportunistic sonar surveys at the site have been conducted between 2008 and 2016 providing one of the most extensive and repeated mapping studies for this type of reef. Previous studies conducted by our group at the site have focused on understanding wave orbital ripple dynamics and scour patterns. In this present study, we analyze the changes apparent at the site itself, focused on the storm-response dynamics of the subway cars. Results have shown that Superstorm Sandy in 2012 produced dramatic changes to the reef structures resulting in the total or partial destruction of eight subway cars within a small (.45 x .2km) portion of the reef site. Winter Storm Jonas in 2016 resulted in the destruction of fewer cars, but rotated a previously static 47m long Navy barge nearly 60 degrees. Once destroyed or collapsed by waves the subway cars go from providing positive structural relief and thus beneficial habitat above the surrounding seabed to being reduced to scattered low relief marine debris. A once popular consideration for reef material, the event and inter-annual decay of subway cars as observed at the Redbird reef provides both a stark indication of the power of storm dynamics on the inner-shelf and a cautionary tale with regards to the selection of seabed reef material.

Unhealthful Food-and-Beverage Advertising in Subway Stations: Targeted Marketing, Vulnerable Groups, Dietary Intake, and Poor Health.

PubMed

Lucan, Sean C; Maroko, Andrew R; Sanon, Omar C; Schechter, Clyde B

2017-04-01

Unhealthful food-and-beverage advertising often targets vulnerable groups. The extent of such advertising in subway stations has not been reported and it is not clear how ad placement may relate to subway ridership or community demographics, or what the implications might be for diets and diet-related health in surrounding communities. Riding all subway lines (n = 7) in the Bronx, NY, USA, investigators systematically assessed all print ads (n = 1586) in all stations (n = 68) in 2012. Data about subway ridership came from the Metropolitan Transportation Authority. Demographic data on surrounding residential areas came from the U.S. Census Bureau. Data on dietary intake and diet-related conditions came from a city health-department survey. There were no ads promoting "more-healthful" food-or-beverage items (i.e., fruits, vegetables, whole grains, nuts, water or milk). There were many ads for "less-healthful" items (e.g., candies, chips, sugary cereals, frozen pizzas, "energy" drinks, coffee confections, hard alcohol, and beer). Ad placement did not relate to the number of riders entering at stations. Instead, exposure to food-or-beverage ads generally, and to "less-healthful" ads particularly (specifically ads in Spanish, directed at youth, and/or featuring minorities), was directly correlated with poverty, lower high-school graduation rates, higher percentages of Hispanics, and/or higher percentages of children in surrounding residential areas. Correlations were robust to sensitivity analyses. Additional analyses suggested correlations between ad exposures and sugary-drink consumption, fruit-and-vegetable intake, and diabetes, hypertension, and high-cholesterol rates. Subway-station ads for "less-healthful" items were located disproportionately in areas home to vulnerable populations facing diet and diet-related-health challenges. The fact that uneven ad placement did not relate to total rider counts suggests ads were not directed at the largest possible audiences but rather targeted to specific groups.

Effects of Experimentally Imposed Noise on Task Performance of Black Children Attending Day Care Centers Near Elevated Subway Trains.

ERIC Educational Resources Information Center

Hambrick-Dixon, Priscilla Janet

1986-01-01

Investigates whether an experimentally imposed 80dB (A) noise affected psychomotor, serial memory words and pictures, incidental memory, visual recall, paired associates, perceptual learning, and coding performance of five-year-old Black children attending day care centers near and far from elevated subways. (HOD)

a New Approach for Subway Tunnel Deformation Monitoring: High-Resolution Terrestrial Laser Scanning

NASA Astrophysics Data System (ADS)

Li, J.; Wan, Y.; Gao, X.

2012-07-01

With the improvement of the accuracy and efficiency of laser scanning technology, high-resolution terrestrial laser scanning (TLS) technology can obtain high precise points-cloud and density distribution and can be applied to high-precision deformation monitoring of subway tunnels and high-speed railway bridges and other fields. In this paper, a new approach using a points-cloud segmentation method based on vectors of neighbor points and surface fitting method based on moving least squares was proposed and applied to subway tunnel deformation monitoring in Tianjin combined with a new high-resolution terrestrial laser scanner (Riegl VZ-400). There were three main procedures. Firstly, a points-cloud consisted of several scanning was registered by linearized iterative least squares approach to improve the accuracy of registration, and several control points were acquired by total stations (TS) and then adjusted. Secondly, the registered points-cloud was resampled and segmented based on vectors of neighbor points to select suitable points. Thirdly, the selected points were used to fit the subway tunnel surface with moving least squares algorithm. Then a series of parallel sections obtained from temporal series of fitting tunnel surfaces were compared to analysis the deformation. Finally, the results of the approach in z direction were compared with the fiber optical displacement sensor approach and the results in x, y directions were compared with TS respectively, and comparison results showed the accuracy errors of x, y, z directions were respectively about 1.5 mm, 2 mm, 1 mm. Therefore the new approach using high-resolution TLS can meet the demand of subway tunnel deformation monitoring.

Chemical Characterization of Outdoor and Subway Fine (PM2.5-1.0) and Coarse (PM10-2.5) Particulate Matter in Seoul (Korea) Computer-Controlled Scanning Electron Microscopy (CCSEM)

EPA Science Inventory

Outdoor and indoor (subway) samples were collected by passive sampling in urban Seoul and analyzed with computer-controlled scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (CCSEM-EDX). Soil/road dust particles accounted for 42-60% (by weight) of fin...

122. View in subway showing air filters for unit turbinegenerator ...

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

122. View in subway showing air filters for unit turbine-generator unit no. 3; looking north. To the left is opening through wall which brings fresh air into the filters; this opening is above the tailrace. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

2007 National Small Business Conference: Critical Infrastructure Opportunities

DTIC Science & Technology

2007-05-18

Flooding of Subway Tunnels From IED Bomber Maximize lives saved – provide time to evacuate Recent advances in inflatable structure technology: • Stronger...Polimetry/ Signal Processing technologies (Radar & Sonar) Low Cost Advanced Composite Structures Low Cost Composite Sandwich Structures and...Ubiquitous Chem/Bio Detect 34 High Impact Technology Solutions Resilient Tunnel Prevent Flooding of Subway Tunnels From IED Bomber Maximize lives saved

[Industrial hygiene for subway train operators].

PubMed

Elizarov, B B; Sin'kov, A V

1995-01-01

Subway train drivers work in specific conditions of underground surroundings, face psychoemotional stress due to high intensity of signals analyzed in short time for the decision, prominent responsibility for passengers' lives. The work is also associated with significant levels of noise, minor artificial illumination, air pollution with dust and unfavorable microclimate. By the end of working shift the drivers demonstrate marked changes in blood pressure, prolonged oculomotor reactions, depressed visual function. Morbidity with transitory disablement is high among the drivers, presenting especially cardiovascular and gastrointestinal diseases. Unfavorable changes of ageing process are seen in the drivers over 35, in age group of 40-49 years (with length of service at least 20 years). The complex investigations helped to elaborate hygienic norms for new subway cars, to base rational schedule ot work and rest for the drivers.

GC-MS/MS Analyses of Biological Samples in Support of Developmental Toxic Effects on Subcutaneous Exposure of Rats to GB

DTIC Science & Technology

2015-11-01

cholinergic symptoms after the release of GB in the Tokyo subway system (Ohbu et al., 1997). In fact, infants and small children may be at greater...Matsui, R.; Sakurai, K.; Hinohara, S. Sarin Poisoning on Tokyo Subway . South. Med. J. 1997, 90, 587–593. Russell, R.W.; Overstreet, D.H. Mechanisms

Subway Subsidence Monitoring and Analysis in Beijing through Envisat-Asar and Terrasar-X DATA

NASA Astrophysics Data System (ADS)

Duan, G.; Gong, H.; Chen, B.; Li, X.

2014-12-01

Subway plays a significant role in public transport in Beijing, China. The safe operation of such underground rail transports are serious threatened by ground subsidence that mainly caused by groundwater over-exploitation. It is necessary to carry out a continuous observation and analysis of the surface deformation along the newly built rails. The paper mainly studied four subways which were built in different periods(see attachment). Envisat-ASAR and Terrasar-X images of the study area were selected to measure the ground deformation. Interferometric Point Target Analysis method was gathered to process the SAR data. The method is developed based on the idea of the Permanent Scatterers SAR Interferometry method which can overcome the decorrelation and atmospheric effect to gain more precise estimation of the ground deformation. The master image can be selected according to the perpendicular, Doppler and temporal baselines to minimize the potential decorrelation. After the registration of all slave images to the master image, the PS candidates would be detected on the basis of the scattering properties of the images. A complex operation of the PSs was conducted to obtain the interferometric phase which was composed of terrain phase, atmospheric phase, deformation phase and noise. A model used for the evaluation of the contribution of each component was built by means of the least squares method. The deformation phase would be the remaining of the interferometric phase minus disturbance terms. Deformation information that came from two different kinds of data was jointly analyzed to reveal the temporal character of the rails before, during and after they were built. The regional LOS(line-of-sight) velocity around a special subway station shows that the rail has suffered from a serious uneven settlement along the rail during the observation period. In addition, time series data revealed the characteristic stages of each PS point. There is a clear accelerating trend of settlement in the construction period of the subway, and the sedimentation velocity would remain very high after a period of the opening of the line. Overall, ground subsidence had a certain delay when compared to the construction and operation of the subway.

Source identification of PM10 pollution in subway passenger cabins using positive matrix factorization

NASA Astrophysics Data System (ADS)

Park, Duckshin; Oh, Miseok; Yoon, Younghun; Park, Eunyoung; Lee, Kiyoung

2012-03-01

Monitoring the air quality in subway passenger cabins is important because of the large number of passengers and potentially high levels of air pollution. This report characterized PM10 levels in subway cabins in Seoul, Korea, and identified PM10 sources using elemental analysis and receptor modeling. PM10 levels in subway cabins were continuously measured using a light scattering monitor during rush and non-rush hours. A total of 41 measurements were taken during rush and non-rush hours, and the measurements were repeated in all four seasons. Filter samples were also collected for elemental composition analysis. Major PM10 sources were identified using positive matrix factorization (PMF). The in-cabin PM10 concentrations were the highest in the winter at 152.8 μg m-3 during rush hours and 90.2 μg m-3 during non-rush hours. While PM10 levels were higher during rush hours than during non-rush hours in three seasons (excluding summer), these levels were not associated with number of passenger. Elemental analysis showed that the PM10 was composed of 52.5% inorganic elements, 10.2% anions, and 37.3% other. Fe was the most abundant element and significantly correlated (p < 0.01) with Mn (r = 0.97), Ti (r = 0.91), Cr (r = 0.88), Ni (r = 0.89), and Cu (r = 0.88). Fe, Mn, Cr, and Cu are indicators of railroad-related PM10 sources. The PM10 sources characterized by PMF were soil and road dust sources (27.2%), railroad-related sources (47.6%), secondary nitrate sources (16.2%), and a chlorine factor mixed with a secondary sulfate source (9.1%). Overall, railroad-related sources contributed the most PM10 to subway cabin air.

The impact of health claims and food deprivation levels on health risk perceptions of fast-food restaurants.

PubMed

Cadario, Romain

2016-01-01

We examined the effect of health claims and food deprivation levels on the health risk perceptions of fast-food restaurants. Consistent with previous research, we used a within-subjects experimental design to manipulate the health claims of fast-food restaurants using real brands: Subway, expressing strong health claims vs. McDonald's, expressing weak health claims. Participants who did not have access to nutrition information were asked to estimate the health risk associated with food items that were slightly more caloric for Subway than McDonald's (640 kcal vs. 600 kcal). We collected data through a web survey with a sample consisting of 414 American adults. Based on the USDA Food Insufficiency Indicator, participants were classified into two categorical food deprivation levels: food sufficiency and food insufficiency. We find that risk perceptions for obesity, diabetes and cardiac illnesses are lower (higher) for the restaurant with stronger (lower) health claims, i.e., Subway (McDonald's). Moreover, we also find that food deprivation levels moderate this effect, such that health risk underestimation is aggravated for individuals who suffer from food insufficiency. More precisely, we find that food insufficient individuals are more responsive to health claims, such that they perceive less health risk than food sufficient individuals for the restaurant with stronger health claims (Subway). Exploring the underlying mechanism of the latter effect, we found that dietary involvement mediates the relationship between food deprivation levels and health risk perceptions for the restaurant with stronger health claims (Subway). These results provide an interdisciplinary contribution in consumer psychology and public health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design and evaluation of a suspension seat to reduce vibration exposure of subway operators: a case study.

PubMed

Marcotte, Pierre; Beaugrand, Sylvie; Boutin, Jérôme; Larue, Christian

2010-01-01

Subway operators have complained about discomfort caused by whole-body vibration. To address this problem, a suspension seat with extensive ergonomic features has been adapted to the confined space of the subway operator cab. The suspension was modified from an existing suspension in order to reduce the dominant frequency of the subway vertical vibration (2.4 Hz). The suspension seat has been extensively tested on a vertical hydraulic shaker. These tests have shown that the SEAT value was lower for a higher vibration level, for higher subject weight, and for the suspension adjusted at median height. The seat also produces a lower SEAT value when there was a predominance of the 6 Hz vibration component. The horizontal seat adjustments had no influence on the suspension SEAT value. Removing the suspension damper also decreases the SEAT value for all the tested configurations. The final version of the suspension seat prototype was validated during normal subway operation with 19 different operators having weight in the 5th, 50th and 95th percentile of the operator population. Accelerations were measured with triaxial accelerometers at the seat cushion, above the suspension and on the floor. In addition to the vibration measurements, each operator was asked about his perceived discomfort from vibration exposure. Globally, the suspension seat attenuated the vertical vibration (SEAT values from 0.86 to 0.99), but discomfort due to amplification of the 2.4 Hz component occurred when the suspension height was adjusted at the minimum, even when the global weighted acceleration was lower (SEAT value < 1). These results suggest that in order to reduce the discomfort caused by whole-body vibration, the transmissibility of the seat should also be considered, in particular when there is a dominant frequency in the vibration spectra.

Estimation of inhaled airborne particle number concentration by subway users in Seoul, Korea.

PubMed

Kim, Minhae; Park, Sechan; Namgung, Hyeong-Gyu; Kwon, Soon-Bark

2017-12-01

Exposure to airborne particulate matter (PM) causes several diseases in the human body. The smaller particles, which have relatively large surface areas, are actually more harmful to the human body since they can penetrate deeper parts of the lungs or become secondary pollutants by bonding with other atmospheric pollutants, such as nitrogen oxides. The purpose of this study is to present the number of PM inhaled by subway users as a possible reference material for any analysis of the hazards to the human body arising from the inhalation of such PM. Two transfer stations in Seoul, Korea, which have the greatest number of users, were selected for this study. For 0.3-0.422 μm PM, particle number concentration (PNC) was highest outdoors but decreased as the tester moved deeper underground. On the other hand, the PNC between 1 and 10 μm increased as the tester moved deeper underground and showed a high number concentration inside the subway train as well. An analysis of the particles to which subway users are actually exposed to (inhaled particle number), using particle concentration at each measurement location, the average inhalation rate of an adult, and the average stay time at each location, all showed that particles sized 0.01-0.422 μm are mostly inhaled from the outdoor air whereas particles sized 1-10 μm are inhaled as the passengers move deeper underground. Based on these findings, we expect that the inhaled particle number of subway users can be used as reference data for an evaluation of the hazards to health caused by PM inhalation. Copyright © 2017 Elsevier Ltd. All rights reserved.

A new look at inhalable metalliferous airborne particles on rail subway platforms.

PubMed

Moreno, Teresa; Martins, Vânia; Querol, Xavier; Jones, Tim; BéruBé, Kelly; Minguillón, Maria Cruz; Amato, Fulvio; Capdevila, Marta; de Miguel, Eladio; Centelles, Sonia; Gibbons, Wes

2015-02-01

Most particles breathed on rail subway platforms are highly ferruginous (FePM) and extremely small (nanometric to a few microns in size). High magnification observations of particle texture and chemistry on airborne PM₁₀ samples collected from the Barcelona Metro, combined with published experimental work on particle generation by frictional sliding, allow us to propose a general model to explain the origin of most subway FePM. Particle generation occurs by mechanical wear at the brake-wheel and wheel-rail interfaces, where magnetic metallic flakes and splinters are released and undergo progressive atmospheric oxidation from metallic iron to magnetite and maghemite. Flakes of magnetite typically comprise mottled mosaics of octahedral nanocrystals (10-20 nm) that become pseudomorphed by maghemite. Continued oxidation results in extensive alteration of the magnetic nanostructure to more rounded aggregates of non-magnetic hematite nanocrystals, with magnetic precursors (including iron metal) still preserved in some particle cores. Particles derived from steel wheel and rails contain a characteristic trace element chemistry, typically with Mn/Fe=0.01. Flakes released from brakes are chemically very distinctive, depending on the pad composition, being always carbonaceous, commonly barium-rich, and texturally inhomogeneous, with trace elements present in nanominerals incorporated within the crystalline structure. In the studied subway lines of Barcelona at least there appears to be only a minimal aerosol contribution from high temperature processes such as sparking. To date there is no strong evidence that these chemically and texturally complex inhalable metallic materials are any more or less toxic than street-level urban particles, and as with outdoor air, the priority in subway air quality should be to reduce high mass concentrations of aerosol present in some stations. Copyright © 2014. Published by Elsevier B.V.

Transient variation of aerosol size distribution in an underground subway station.

PubMed

Kwon, Soon-Bark; Namgung, Hyeong-Gyu; Jeong, Wootae; Park, Duckshin; Eom, Jin Ki

2016-06-01

As the number of people using rapid transit systems (subways) continues to rise in major cities worldwide, increasing attention has been given to the indoor air quality of underground stations. This study intended to observe the change of PM distribution by size in an underground station with PSDs installed located near the main road in downtown Seoul, as well as to examine causes for the changes. The results indicate that the PM suspended in the tunnel flowed into the platform area even in a subway station where the effect of train-induced wind is blocked by installed PSDs, as this flow occurred when the PSDs were opened. The results also indicate that coarse mode particles generated by mechanical friction in the tunnel, such as that between wheels and rail, also flowed into the platform area. The PM either settled or was re-suspended according to size and whether the ventilation in the platform area was in operation or if the platform floor had been washed. The ventilation system was more effective in removing PM of smaller sizes (fine particles) while the wash-out performed after train operations had stopped reduced the suspension of coarse mode particles the next morning. Despite installation of the completely sealed PSDs, inflow of coarse mode particles from the tunnel seems unavoidable, indicating the need for measures to decrease the PM generated there to lower subway user exposure since those particles cannot be reduced by mechanical ventilation alone. This research implicate that coarse PM containing heavy metals (generated from tunnel side) proliferated especially during rush hours, during which it is very important to control those PM in order to reduce subway user exposure to this hazardous PM.

Major depressive disorder, panic disorder, and post-traumatic stress disorder in Korean subway drivers.

PubMed

Kim, Hyoung-Ryoul; Yim, Hyeon Woo; Jo, Sun-Jin; Choi, Bongkyoo; Jeong, Seung Hee; Lee, Kang Sook; Park, Jong-Ik; Chang, Sung Man

2013-05-01

The purposes of this study are to investigate the prevalence of major depressive disorder, panic disorder, and post-traumatic stress disorder (PTSD) in Korean subway drivers, and find the association between these disorders and the drivers' person-under-train (PUT) experiences. A total of 826 subway drivers who participated in a cross-sectional work and health survey were included for this study. The Korean version of the Composite International Diagnostic Interview 2.1 was applied to assess major depressive disorder, panic disorder, and PTSD. The date of PUT, whether victim died, and how many PUTs the drivers experienced were asked using a structured questionnaire. The standardized prevalence ratios (SPRs) for lifetime prevalence of panic disorder and PTSD in subway drivers were 13.3 (95 % confidence interval [CI] 6.6-22.4) and 2.1 (95 % CI 1.1-3.4), respectively. In lifetime prevalence, after adjusting for age, education, income, and working career, the drivers who experienced PUT had significantly higher risks for panic disorder (odds ratio [OR] = 4.2, 95 % CI 1.2-16.6) and PTSD (OR = 4.4, 95 % CI 1.3-16.4). In 1-year prevalence, the drivers who experienced PUT had a significantly higher risk for PTSD (OR = 11.7, 95 % CI 1.9-225.8). There was no significant value of SPR and OR in major depressive disorder. This study suggests that Korean subway drivers are at higher risk for panic disorder and PTSD compared to the general population, and PUT experience is associated with panic disorder and PTSD. Drivers who have experienced PUT should be treated quickly, sympathetically, and sensitively by a psychological professional and their colleagues, so they can return to work soon.

Comfort parameters - Ventilation of a subway wagon

NASA Astrophysics Data System (ADS)

Petr, Pavlíček; Ladislav, Tříska

2017-09-01

Research and development of a ventilation system is being carried out as a part of project TA04030774 of the Technology Agency of the Czech Republic. Name of the project is "Research and Development of Mass-optimized Components for Rail Vehicles". Problems being solved are development and testing of a new concept for ventilation systems for public transport vehicles. The main improvements should be a reduction of the mass of the whole system, easy installation and reduction of the noise of the ventilation system. This article is focused on the comfort parameters in a subway wagon (measurement and evaluation carried out on a function sample in accordance with the regulations). The input to the project is a ventilator hybrid casing for a subway wagon, which was manufactured and tested during the Ministry of Industry and Trade project TIP FR-TI3/449.

Interactions of ClO2 and H2O2 Fumigants with Dirt and Grime ...

EPA Pesticide Factsheets

Report The primary objective of this research was to evaluate the impact that dirt and grime, as present on unpainted subway concrete, may have on fumigation efficacy. Other objectives include determining which sampling procedure provides better recovery from grimed and cleaned concrete, and characterizing subway material before and after cleaning using a prescribed method from the New York City Metropolitan Transportation Authority (MTA).

Beneath the Surface: Intelligence Preparation of the Battlespace for Counterterrorism

DTIC Science & Technology

2004-11-01

consisting of those sub-systems existing below ground to include subways , sewers, utility structures and others.161 Although 155 Three reasons adapted...activities that provide for governance and basic human needs. Roads, subways , waterways, railroads and sea and airports are a few of the elements of the...recruiting, financing, and service (medicine, food , education) delivery oper- ations. Finally, the con- cept of avenues has parallels in cyberspace and

Aerodynamics as a subway design parameter

NASA Technical Reports Server (NTRS)

Kurtz, D. W.

1976-01-01

A parametric sensitivity study has been performed on the system operational energy requirement in order to guide subway design strategy. Aerodynamics can play a dominant or trivial role, depending upon the system characteristics. Optimization of the aerodynamic parameters may not minimize the total operational energy. Isolation of the station box from the tunnel and reduction of the inertial power requirements pay the largest dividends in terms of the operational energy requirement.

Field experiment and numerical simulation of coupling non-Darcy flow caused by curtain and pumping well in foundation pit dewatering

NASA Astrophysics Data System (ADS)

Wang, Jianxiu; Liu, Xiaotian; Wu, Yuanbin; Liu, Shaoli; Wu, Lingao; Lou, Rongxiang; Lu, Jiansheng; Yin, Yao

2017-06-01

High-velocity non-Darcy flow produced larger drawdown than Darcy flow under the same pumping rate. When the non-Darcy flow caused by curtain met non-Darcy flow caused by pumping wells, superposition and amplification effect occurred in the coupling area, the non-Darcy flow was defined as coupling non-Darcy flow. The coupling non-Darcy flow can be produced and controlled using different combination of curtain and pumping wells in foundation pit dewatering to obtain the maximum drawdown using the minimum pumping rate. The Qianjiang Century City Station foundation pit of Hangzhou subway, China, was selected as background. Field experiments were performed to observe the coupling non-Darcy flow in round gravel. A generalized conceptual model was established to study the coupling effect under different combination of curtain and pumping wells. Numerical simulations of the coupling non-Darcy flow in foundation pit dewatering were carried out based on the Forchheimer equation. The non-Darcy flow area and flow velocity were influenced by the coupling effect. Short filter tube, large pumping rate, small horizontal distance between filter tube and diaphragm wall, and small vertical distance between the filter tube and confined aquifer roof effectively strengthened the coupling effect and obtained a large drawdown. The pumping wells installed close to a curtain was an intentional choice designed to create coupling non-Darcy flow and obtain the maximize drawdown. It can be used in the dewatering of a long and narrow foundation pit, such as a subway foundation pit.

The Guardian. Volume 10, Number 2, Winter 2008

DTIC Science & Technology

2008-01-01

incidents include the sarin attack in the Tokyo subway (1995); the US domestic terrorist bombing of the Murrah Federal Building (1995); the Khobar...Towers bombing (1996) in Saudi Arabia; the maritime bombing of the USS COLE (2000) in Yemen; the London subway and bus bombings (July 7, 2005); and...its franchising by making links where none exist. For example, the cult members arrested in Miami should not be called members of al Qaeda; and

Non-State Actors and their Risks to American Society

DTIC Science & Technology

2013-03-01

done in house but out of sight of the broader Japanese community.31 The attack was conducted by dispersing the anthrax spores from an elevated...a spiritual cleansing ritual and that the police could not enter. Since Japanese law protects religious freedom and practices, the police departed...created their weapon system in house and their target was the broader Japanese populace. The Tokyo subway system is among the heaviest used subway

On the calculation of air flow rates to ventilate closed-type stations in subway with the double-track tunnel

NASA Astrophysics Data System (ADS)

Kiyanitsa, LA

2018-03-01

Metro is not only the most promising kind of public transport but also an important part of infrastructure in a modern city. As a place where large groups of people gather, subway is to ensure the required air exchange at the passenger platforms of the stations. The air flow rate for airing the stations is also determined based on the required temperature, humidity and MAC of gases. The present study estimates the required air flow rate at the passenger platform of the closed-type subway station with the double-track tunnel given the standard air temperature, humidity and gas concentration, as well as based on the condition of the specified air flow feed and air changes per hour. The article proposes the scheme of air recirculation from the double-track tunnel to the station.

Ground Subsidence Monitoring with MT-InSAR and Mechanism Inversion Over Xi'an, China

NASA Astrophysics Data System (ADS)

Peng, M. M.; Zhao, C. Y.; Zhang, Q.; Zhang, J.; Liu, Y. Y.

2018-04-01

The ancient Xi'an, China, has been suffering severe land subsidence and ground fissure hazards since the 1960s, which has affected the safety of Subways. Multi-sensor SAR data are conducted to monitor the latest complex ground deformation and its influence on subway line No.3 over Xi'an. Annual deformation rates have been retrieved to reveal the spatiotemporal evolution of ground subsidence in Xi'an city from 2013 to 2017. Meanwhile, the correlation between land subsidence and ground fissures are analyzed by retrieving the deformation differences in both sides of the fissures. Besides, the deformation along subway line No. 3 is analyzed, and the fast deformation section is quantitatively studied. Finally, a flat lying sill model with distributed contractions is implemented to model the InSAR deformation over YHZ subsidence center, which manifests that the ground deformation is mainly caused by groundwater withdrawal.

ScienceToGo.org: The Strengths and Weaknesses of Communicating Climate Change through Mass Transit Advertising Spaces

NASA Astrophysics Data System (ADS)

Lustick, D. S.; Lohmeier, J.; Chen, R. F.; Wilson, R.; Rabkin, D.; Thompson, S. R.

2016-02-01

Engaging urban populations with climate change science is a difficult challenge since cities can seem so removed from the `natural environment.' However, mass transit provides an inherent means of communicating environmental messages with a cross section of the urban population. The Out of Home Media (OHM) spaces found on platforms and inside train cars provide a potentially effective means of bringing informal science learning opportunities directly to an underserved STEM audience. Our team felt that any messaging curriculum for a coastal urban subway system must complement the scary reality of the impacts of a changing climate (i.e. rising sea levels) with current examples of how the city is preparing for a more sustainable future. Urban areas such as Boston must develop adaptation and mitigation strategies that will help them not only survive, but thrive in a changing environment. In 2013-14, ScienceToGo.org ran a series of 12 engaging posters and placards staring `Ozzie the Ostrich' on the Massachusetts Bay Transit Authority's Red and Orange subway lines targeting an audience of more than 400,000 riders per day. The 12 month curriculum was divided into three phases: reality, relevance, and hope. During the presentation, we will present the results of our quasi-experimental research which identifies, quantifies, and explains the observed impacts of the campaign on adult riders. The strengths and weaknesses of the communication strategy will be discussed. Finally, we will conclude with some recommendations for how this work could improve and inform other urban informal science learning initiatives.

Laboratory Determination of Horizontal Stress in Cohesionless Soil.

DTIC Science & Technology

1983-01-01

in soft silty clay. The sheet piles were used for excavation support for the Oslo subway construction and the measurements of the lateral stresses 4...5.2. By sandwiching the stress cell between two butyl rubber diaphragms in the chamber, a uniform uniaxial stress could be applied to the 4 stress...October 1944, pp. 355-358. .4 162 Johannessen, I. J., "Test Section and Installation of Test Equipment, Oslo Subway ," Pro Brussels Confer- ence on

Concentration and characterization of airborne particles in Tehran's subway system.

PubMed

Kamani, Hosein; Hoseini, Mohammad; Seyedsalehi, Mahdi; Mahdavi, Yousef; Jaafari, Jalil; Safari, Gholam Hosein

2014-06-01

Particulate matter is an important air pollutant, especially in closed environments like underground subway stations. In this study, a total of 13 elements were determined from PM10 and PM2.5 samples collected at two subway stations (Imam Khomeini and Sadeghiye) in Tehran's subway system. Sampling was conducted in April to August 2011 to measure PM concentrations in platform and adjacent outdoor air of the stations. In the Imam Khomeini station, the average concentrations of PM10 and PM2.5 were 94.4 ± 26.3 and 52.3 ± 16.5 μg m(-3) in the platform and 81.8 ± 22.2 and 35 ± 17.6 μg m(-3) in the outdoor air, respectively. In the Sadeghiye station, mean concentrations of PM10 and PM2.5 were 87.6 ± 23 and 41.3 ± 20.4 μg m(-3) in the platform and 73.9 ± 17.3 and 30 ± 15 μg m(-3), in the outdoor air, respectively. The relative contribution of elemental components in each particle fraction were accounted for 43% (PM10) and 47.7% (PM2.5) in platform of Imam Khomeini station and 15.9% (PM10) and 18.5% (PM2.5) in the outdoor air of this station. Also, at the Sadeghiye station, each fraction accounted for 31.6% (PM10) and 39.8% (PM2.5) in platform and was 11.7% (PM10) and 14.3% (PM2.5) in the outdoor. At the Imam Khomeini station, Fe was the predominant element to represent 32.4 and 36 % of the total mass of PM10 and PM2.5 in the platform and 11.5 and 13.3% in the outdoor, respectively. At the Sadeghiye station, this element represented 22.7 and 29.8% of total mass of PM10 and PM2.5 in the platform and 8.7 and 10.5% in the outdoor air, respectively. Other major crustal elements were 5.8% (PM10) and 5.3% (PM2.5) in the Imam Khomeini station platform and 2.3 and 2.4% in the outdoor air, respectively. The proportion of other minor elements was significantly lower, actually less than 7% in total samples, and V was the minor concentration in total mass of PM10 and PM2.5 in both platform stations.

Energy Expenditure and Metabolic Heat Production Storage Estimates of Tactical Law Enforcement Personnel during Chemical, Biological, Radiological, and Nuclear (CBRN) Training

DTIC Science & Technology

2011-09-01

the chemical attack of the Tokyo subway system in 1995, increased attention to preparedness for CBRN disasters has been emphasized (12, 17...1996. 17. Okumura, T., Suzuki, K., Fukuda, A., Kohama, A., Takasu, N., Ishimatsu, S., and Hinchara, S. The Tokyo subway Sarin attack: disaster... sandwiched within tough DuPont™ Nomex® outer and inner layers.  Streamlined design and light weight deliver optimum comfort and natural freedom of

Raman lidar for remote control explosives in the subway

NASA Astrophysics Data System (ADS)

Grishkanich, Aleksandr; Redka, Dmitriy; Vasiliev, Sergey; Tishkov, Victor; Zhevlakov, Aleksandr

2017-10-01

Laser sensing can serve as a highly effective method of searching and monitoring of explosives in the subway. The first method is essence consists in definition the explosives concentration by excitation and registration ramans shifts at wavelength of λ = 0.261 - 0.532 μm at laser sounding. Preliminary results of investigation show the real possibility to register of 2,4,6-trinitrophenylmethylnitramine with concentration on surface at level of 108÷109 cm-3 on a safe distance 50 m from the object.

The Improvement on the Xinjiekou Subway Transfer Channel of Nanjing

NASA Astrophysics Data System (ADS)

Xu, X. D.; Zheng, C. J.

The subway, which is an effective way to alleviate the traffic congestion, has gradually been constructed in many cities. With the completion of the construction, the transfer station will become the factor that affects the efficiency of the whole transport network. Based on investigation and analysis of the present situation of the passenger flow, the essay will make a prediction with the multiple linear regression and put forward two kinds of transfer channel improvement schemes for xinjiekou transfer station.

Pedestrians’ behavior in emergency evacuation: Modeling and simulation

NASA Astrophysics Data System (ADS)

Wang, Lei; Zheng, Jie-Hui; Zhang, Xiao-Shuang; Zhang, Jian-Lin; Wang, Qiu-Zhen; Zhang, Qian

2016-11-01

The social force model has been widely used to simulate pedestrian evacuation by analyzing attractive, repulsive, driving, and fluctuating forces among pedestrians. Many researchers have improved its limitations in simulating behaviors of large-scale population. This study modifies the well-accepted social force model by considering the impacts of interaction among companions and further develops a comprehensive model by combining that with a multi-exit utility function. Then numerical simulations of evacuations based on the comprehensive model are implemented in the waiting hall of the Wulin Square Subway Station in Hangzhou, China. The results provide safety thresholds of pedestrian density and panic levels in different operation situations. In spite of the operation situation and the panic level, a larger friend-group size results in lower evacuation efficiency. Our study makes important contributions to building a comprehensive multi-exit social force model and to applying it to actual scenarios, which produces data to facilitate decision making in contingency plans and emergency treatment. Project supported by the National Natural Science Foundation of China (Grant No. 71471163).

A Study on Characteristics of Atmospheric Heavy Metals in Subway Station

PubMed Central

Kim, Chun-Huem; Yoo, Dong-Chul; Kwon, Young-Min; Han, Woong-Soo; Kim, Gi-Sun; Park, Mi-Jung; Kim, Young Soon

2010-01-01

In this study, we investigated the atmospheric heavy metal concentrations in the particulate matter inside the subway stations of Seoul. In particular, we examined the correlation between the heavy metals and studied the effect of the heavy metals on cell proliferation. In six selected subway stations in Seoul, particulate matter was captured at the platforms and 11 types of heavy metals were analyzed. The results showed that the mean concentration of iron was the highest out of the heavy metals in particulate matter, followed by copper, potassium, calcium, zinc, nickel, sodium, manganese, magnesium, chromium and cadmium in that order. The correlation analysis showed that the correlations between the heavy metals was highest in the following order: (Cu vs Zn) , (Ca vs Na) , (Ca vs Mn) , (Ni vs Cr) , (Na vs Mn) , (Cr vs Cd) , (Zn vs Cd) , (Cu vs Cd) , (Ni vs Cd) , (Cu vs Ni) , (K vs Zn) , (Cu vs K) , (Cu vs Cr) , (K vs Cd) , (Zn vs Cr) , (K vs Ni) , (Zn vs Ni) , (K vs Cr) , and (Fe vs Cu) . The correlation coefficient between zinc and copper was 0.937, indicating the highest correlation. Copper, zinc, nickel, chromium and cadmium, which are generated from artificial sources in general, showed correlations with many of the other metals and the correlation coefficients were also relatively high. The effect of the heavy metals on cell proliferation was also investigated in this study. Cultured cell was exposed to 10 mg/l or 100 mg/l of iron, copper, calcium, zinc, nickel, manganese, magnesium, chromium and cadmium for 24 hours. The cell proliferation in all the heavy metal-treated groups was not inhibited at 10 mg/l of the heavy metal concentration. The only exception to this was with the cadmium-treated group which showed a strong cell proliferation inhibition. This study provides the fundamental data for the understanding of simultaneous heavy metal exposure tendency at the time of particulate matter exposure in subway stations and the identification of heavy metal sources. Moreover, this study can be used as the fundamental data for the cell toxicity study of the subway-oriented heavy metal-containing particulate matter. PMID:24278519

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

PubMed

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

2014-05-01

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

Assessment of the noise annoyance among subway train conductors in Tehran, Iran.

PubMed

Hamidi, Mansoureh; Kavousi, Amir; Zaheri, Somayeh; Hamadani, Abolfazl; Mirkazemi, Roksana

2014-01-01

Subway transportation system is a new phenomenon in Iran. Noise annoyance interferes with the individual's task performance, and the required alertness in the driving of subway trains. This is the first study conducted to measure the level of noise and noise annoyance among conductors of subway organization in Tehran, Iran. This cross sectional study was conducted among 167 randomly selected train conductors. Information related to noise annoyance was collected by using a self-administered questionnaire. The dosimetry and sound metering was done for the conductors and inside the cabins. There were 41 sound metering measuring samples inside the conductors' cabin, and there were 12 samples of conductors' noise exposure. The results of sound level meter showed that the mean Leq was 73.0 dBA ± 8.7 dBA and the dosimetry mean measured Leq was 82.1 dBA ± 6.8 dBA. 80% of conductors were very annoyed/annoyed by noise in their work place. 53.9% of conductors reported that noise affected their work performance and 63.5% reported that noise causes that they lose their concentration. The noise related to movement of train wheels on rail was reported as the worst by 83.2% followed by the noise of brakes (74.3%) and the ventilation noise (71.9%). 56.9% of conductors reported that they are suffering from sleeplessness, 40.1% from tinnitus and 80.2% feeling fatigue and sleepy. The study results showed the high level of noise and noise annoyance among train conductors and the poor health outcome of their exposure to this level of noise.

Modelling large scale human activity in San Francisco

NASA Astrophysics Data System (ADS)

Gonzalez, Marta

2010-03-01

Diverse group of people with a wide variety of schedules, activities and travel needs compose our cities nowadays. This represents a big challenge for modeling travel behaviors in urban environments; those models are of crucial interest for a wide variety of applications such as traffic forecasting, spreading of viruses, or measuring human exposure to air pollutants. The traditional means to obtain knowledge about travel behavior is limited to surveys on travel journeys. The obtained information is based in questionnaires that are usually costly to implement and with intrinsic limitations to cover large number of individuals and some problems of reliability. Using mobile phone data, we explore the basic characteristics of a model of human travel: The distribution of agents is proportional to the population density of a given region, and each agent has a characteristic trajectory size contain information on frequency of visits to different locations. Additionally we use a complementary data set given by smart subway fare cards offering us information about the exact time of each passenger getting in or getting out of the subway station and the coordinates of it. This allows us to uncover the temporal aspects of the mobility. Since we have the actual time and place of individual's origin and destination we can understand the temporal patterns in each visited location with further details. Integrating two described data set we provide a dynamical model of human travels that incorporates different aspects observed empirically.

Automatic crack detection and classification method for subway tunnel safety monitoring.

PubMed

Zhang, Wenyu; Zhang, Zhenjiang; Qi, Dapeng; Liu, Yun

2014-10-16

Cracks are an important indicator reflecting the safety status of infrastructures. This paper presents an automatic crack detection and classification methodology for subway tunnel safety monitoring. With the application of high-speed complementary metal-oxide-semiconductor (CMOS) industrial cameras, the tunnel surface can be captured and stored in digital images. In a next step, the local dark regions with potential crack defects are segmented from the original gray-scale images by utilizing morphological image processing techniques and thresholding operations. In the feature extraction process, we present a distance histogram based shape descriptor that effectively describes the spatial shape difference between cracks and other irrelevant objects. Along with other features, the classification results successfully remove over 90% misidentified objects. Also, compared with the original gray-scale images, over 90% of the crack length is preserved in the last output binary images. The proposed approach was tested on the safety monitoring for Beijing Subway Line 1. The experimental results revealed the rules of parameter settings and also proved that the proposed approach is effective and efficient for automatic crack detection and classification.

Alcohol advertising at Boston subway stations: an assessment of exposure by race and socioeconomic status.

PubMed

Gentry, Elisabeth; Poirier, Katie; Wilkinson, Tiana; Nhean, Siphannay; Nyborn, Justin; Siegel, Michael

2011-10-01

We investigated the frequency of alcohol ads at all 113 subway and streetcar stations in Boston and the patterns of community exposure stratified by race, socioeconomic status, and age. We assessed the extent of alcohol advertising at each station in May 2009. We measured gross impressions and gross rating points (GRPs) for the entire Greater Boston population and for Boston public school student commuters. We compared the frequency of alcohol advertising between neighborhoods with differing demographics. For the Greater Boston population, alcohol advertising at subway stations generated 109 GRPs on a typical day. For Boston public school students in grades 5 to 12, alcohol advertising at stations generated 134 GRPs. Advertising at stations in low-poverty neighborhoods generated 14.1 GRPs and at stations in high-poverty areas, 63.6 GRPs. Alcohol ads reach the equivalent of every adult in the Greater Boston region and the equivalent of every 5th- to 12th-grade public school student each day. More alcohol ads were displayed in stations in neighborhoods with high poverty rates than in stations in neighborhoods with low poverty rates.

Automatic Crack Detection and Classification Method for Subway Tunnel Safety Monitoring

PubMed Central

Zhang, Wenyu; Zhang, Zhenjiang; Qi, Dapeng; Liu, Yun

2014-01-01

Cracks are an important indicator reflecting the safety status of infrastructures. This paper presents an automatic crack detection and classification methodology for subway tunnel safety monitoring. With the application of high-speed complementary metal-oxide-semiconductor (CMOS) industrial cameras, the tunnel surface can be captured and stored in digital images. In a next step, the local dark regions with potential crack defects are segmented from the original gray-scale images by utilizing morphological image processing techniques and thresholding operations. In the feature extraction process, we present a distance histogram based shape descriptor that effectively describes the spatial shape difference between cracks and other irrelevant objects. Along with other features, the classification results successfully remove over 90% misidentified objects. Also, compared with the original gray-scale images, over 90% of the crack length is preserved in the last output binary images. The proposed approach was tested on the safety monitoring for Beijing Subway Line 1. The experimental results revealed the rules of parameter settings and also proved that the proposed approach is effective and efficient for automatic crack detection and classification. PMID:25325337

Forecasting the daily electricity consumption in the Moscow region using artificial neural networks

NASA Astrophysics Data System (ADS)

Ivanov, V. V.; Kryanev, A. V.; Osetrov, E. S.

2017-07-01

In [1] we demonstrated the possibility in principle for short-term forecasting of daily volumes of passenger traffic in the Moscow metro with the help of artificial neural networks. During training and predicting, a set of the factors that affect the daily passenger traffic in the subway is passed to the input of the neural network. One of these factors is the daily power consumption in the Moscow region. Therefore, to predict the volume of the passenger traffic in the subway, we must first to solve the problem of forecasting the daily energy consumption in the Moscow region.

Comparison of safety equipment between London underground and Beijing subway

NASA Astrophysics Data System (ADS)

Chen, T.; Zhang, S. Y.; Zhao, L. Z.; Xia, J. J.; Fu, X. C.; Bao, Z. M.; Chen, Y.; Zhang, X. Z.; Wang, R. J.; Hu, C.; Jing, L. S.; Wang, Y.

2017-06-01

The purpose of this paper was to improve the safety equipment’s effectiveness through the comparison. Firstly, the history and safety accident of London Underground and Beijing Subway were shown. Secondly, fire equipment between these two cities was compared including station’s hardware installations and carriage’s hardware installations. Thirdly, the relative software installations were also compared such as emergency drills. The results showed that Beijing Subway’s hardware installations were better than London. However, London Underground’s some installations were more effective than Beijing. Both cities would pay more attention on anti-terrorist in tunnel.

Particle exposure and inhaled dose during commuting in Singapore

NASA Astrophysics Data System (ADS)

Tan, Sok Huang; Roth, Matthias; Velasco, Erik

2017-12-01

Exposure concentration and inhaled dose of particles during door-to-door trips walking and using motorized transport modes (subway, bus, taxi) are evaluated along a selected route in a commercial district of Singapore. Concentrations of particles smaller than 2.5 μm in size (PM2.5), black carbon, particle-bound polycyclic aromatic hydrocarbons, number of particles, active surface area and carbon monoxide have been measured in-situ using portable instruments. Simultaneous measurements were conducted at a nearby park to capture the background concentrations. The heart rate of the participants was monitored during the measurements as a proxy of the inhalation rate used to calculate the inhaled dose of particles. All measured metrics were highest and well above background levels during walking. No significant difference was observed in the exposure concentration of PM2.5 for the three motorized transport modes, unlike for the metrics associated with ultrafine particles (UFP). The concentration of these freshly emitted particles was significantly lower on subway trips. The absence of combustion sources, use of air conditioning and screen doors at station platforms are effective measures to protect passengers' health. For other transport modes, sections of trips close to accelerating and idling vehicles, such as bus stops, traffic junctions and taxi stands, represent hotspots of particles. Reducing the waiting time at such locations will lower pollutants exposure and inhaled dose during a commute. After taking into account the effect of inhalation and travel duration when calculating dose, the health benefit of commuting by subway for this particular district of Singapore became even more evident. For example, pedestrians breathe in 2.6 and 3.2 times more PM2.5 and UFP, respectively than subway commuters. Public buses were the second best alternative. Walking emerged as the worst commuting mode in terms of particle exposure and inhaled dose.

Continuously Deformation Monitoring of Subway Tunnel Based on Terrestrial Point Clouds

NASA Astrophysics Data System (ADS)

Kang, Z.; Tuo, L.; Zlatanova, S.

2012-07-01

The deformation monitoring of subway tunnel is of extraordinary necessity. Therefore, a method for deformation monitoring based on terrestrial point clouds is proposed in this paper. First, the traditional adjacent stations registration is replaced by sectioncontrolled registration, so that the common control points can be used by each station and thus the error accumulation avoided within a section. Afterwards, the central axis of the subway tunnel is determined through RANSAC (Random Sample Consensus) algorithm and curve fitting. Although with very high resolution, laser points are still discrete and thus the vertical section is computed via the quadric fitting of the vicinity of interest, instead of the fitting of the whole model of a subway tunnel, which is determined by the intersection line rotated about the central axis of tunnel within a vertical plane. The extraction of the vertical section is then optimized using RANSAC for the purpose of filtering out noises. Based on the extracted vertical sections, the volume of tunnel deformation is estimated by the comparison between vertical sections extracted at the same position from different epochs of point clouds. Furthermore, the continuously extracted vertical sections are deployed to evaluate the convergent tendency of the tunnel. The proposed algorithms are verified using real datasets in terms of accuracy and computation efficiency. The experimental result of fitting accuracy analysis shows the maximum deviation between interpolated point and real point is 1.5 mm, and the minimum one is 0.1 mm; the convergent tendency of the tunnel was detected by the comparison of adjacent fitting radius. The maximum error is 6 mm, while the minimum one is 1 mm. The computation cost of vertical section abstraction is within 3 seconds/section, which proves high efficiency..

An investigation of the PM2.5 and NO2 concentrations and their human health impacts in the metro subway system of Suzhou, China.

PubMed

Cao, Shi-Jie; Kong, Xiang-Ri; Li, Linyan; Zhang, Weirong; Ye, Zi-Ping; Deng, Yelin

2017-05-24

This study measured the particle concentrations with an aerodynamic diameter smaller than 2.5 μm (PM 2.5 ), nitrogen dioxide (NO 2 ), and relative humidity (RH) at five metro subway stations in Suzhou's subway system (Lines 1 and 2). The real-time monitoring campaign was conducted from March 30 th to April 10 th and August 4 th to August 21 st , 2015. The monitoring practice was carried out during rush (7:00-9:00 AM and 17:00-19:00 PM) and regular hours (other times) at the ground and underground levels under different weather conditions with a purpose of obtaining representative data. The monitored results show that the concentrations of PM 2.5 in the train carriages were lower than the concentrations at the underground platforms during both spring and summer. The mean PM 2.5 concentrations at all the underground platforms in all the sub-stations monitored were significantly higher than those at the ground level. The human health impact was calculated to be 6300 annual DALYs (or 375 deaths) due to exposure to the subway system in Suzhou according to the UNEP-SETAC toxicity (USEtox) model. Linear regression models were applied to evaluate the relationships between the PM 2.5 , NO 2 concentrations, and RH. We found that a 10% increment in RH from the current average level of 50-60% can lead to a 9.8 μg m -3 concentration decrease in PM 2.5 . This further results in the total human health impact being reduced to 2451 DALYs (150-4753 DALYs), representing a 20% decrease (1.2-38%).

Inactivation of Bacillus anthracis spores to decontaminate subway railcar and related materials via the fogging of peracetic acid and hydrogen peroxide sporicidal liquids.

PubMed

Richter, William R; Wood, Joseph P; Wendling, Morgan Q S; Rogers, James V

2018-01-15

The inactivation of Bacillus anthracis spores on subway and used subway railcar materials was evaluated using fogged peracetic acid/hydrogen peroxide (PAA) and hydrogen peroxide (H 2 O 2 ). A total of 21 separate decontamination tests were conducted using bacterial spores of both B. anthracis Ames (B.a.) and Bacillus atrophaeus (B.g.) inoculated onto several types of materials. Tests were conducted using commercial off-the-shelf fogging equipment filled with either PAA or H 2 O 2 to fumigate a ∼15 cubic meter chamber under uncontrolled ambient relative humidity and controlled temperature (10 or 20 °C) from 8 to 168 h. For the present study, no conditions were found that resulted in complete inactivation of either B.a. Ames or B.g. on all test materials. Approximately 41% and 38% of the decontamination efficacies for B.a. and B.g., respectively, exhibited ≥6 log 10 reduction (LR); efficacy depended greatly on the material. When testing at 10 °C, the mean LR was consistently lower for both B.a. and B.g. as compared to 20 °C. Based on the statistical comparison of the LR results, B.g. exhibited equivalent or greater resistance than B.a. for approximately 92% of the time across all 21 tests. The efficacy data suggest that B.g. may be a suitable surrogate for B.a. Ames when assessing the decontamination efficacy of fogged PAA or H 2 O 2 . Moreover, the results of this testing indicate that in the event of B.a. spore release into a subway system, the fogging of PAA or H 2 O 2 represents a decontamination option for consideration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Picture Wall (Glass Structures)

NASA Technical Reports Server (NTRS)

1978-01-01

Photo shows a subway station in Toronto, Ontario, which is entirely glass-enclosed. The all-glass structure was made possible by a unique glazing concept developed by PPG Industries, Pittsburgh, Pennsylvania, one of the largest U.S. manufacturers of flat glass. In the TVS glazing system, transparent glass "fins" replace conventional vertical support members used to provide support for wind load resistance. For stiffening, silicone sealant bonds the fins to adjacent glass panels. At its glass research center near Pittsburgh, PPG Industries uses the NASTRAN computer program to analyze the stability of enclosures made entirely of glass. The company also uses NASTRAN to simulate stresses on large containers of molten glass and to analyze stress effects of solar heating on flat glass.

Analysis of the influence of Nanchang Metro Line 4 on groundwater

NASA Astrophysics Data System (ADS)

Lan, Yingying

2017-04-01

Nanchang city subway excavation depth and the Quaternary aquifer layers are located at approximately the same depth. After the completion of the subway, that is equivalent to adding a retaining wall in the phreatic aquifer. The metro line 4 influence on groundwater flow field was analyzed based on the groundwater flow field and the dynamic relationship between groundwater and surface water. The result was that the groundwater level would rise in the area of facing groundwater movement, while others decrease. The influence of metro was apparent at the place where hydraulic contact of Gan River with groundwater was good, and vice versa.

Alcohol Advertising at Boston Subway Stations: An Assessment of Exposure by Race and Socioeconomic Status

PubMed Central

Poirier, Katie; Wilkinson, Tiana; Nhean, Siphannay; Nyborn, Justin; Siegel, Michael

2011-01-01

Objectives. We investigated the frequency of alcohol ads at all 113 subway and streetcar stations in Boston and the patterns of community exposure stratified by race, socioeconomic status, and age. Methods. We assessed the extent of alcohol advertising at each station in May 2009. We measured gross impressions and gross rating points (GRPs) for the entire Greater Boston population and for Boston public school student commuters. We compared the frequency of alcohol advertising between neighborhoods with differing demographics. Results. For the Greater Boston population, alcohol advertising at subway stations generated 109 GRPs on a typical day. For Boston public school students in grades 5 to 12, alcohol advertising at stations generated 134 GRPs. Advertising at stations in low-poverty neighborhoods generated 14.1 GRPs and at stations in high-poverty areas, 63.6 GRPs. Conclusions. Alcohol ads reach the equivalent of every adult in the Greater Boston region and the equivalent of every 5th- to 12th-grade public school student each day. More alcohol ads were displayed in stations in neighborhoods with high poverty rates than in stations in neighborhoods with low poverty rates. PMID:21852632

Smartphone Location-Independent Physical Activity Recognition Based on Transportation Natural Vibration Analysis.

PubMed

Hur, Taeho; Bang, Jaehun; Kim, Dohyeong; Banos, Oresti; Lee, Sungyoung

2017-04-23

Activity recognition through smartphones has been proposed for a variety of applications. The orientation of the smartphone has a significant effect on the recognition accuracy; thus, researchers generally propose using features invariant to orientation or displacement to achieve this goal. However, those features reduce the capability of the recognition system to differentiate among some specific commuting activities (e.g., bus and subway) that normally involve similar postures. In this work, we recognize those activities by analyzing the vibrations of the vehicle in which the user is traveling. We extract natural vibration features of buses and subways to distinguish between them and address the confusion that can arise because the activities are both static in terms of user movement. We use the gyroscope to fix the accelerometer to the direction of gravity to achieve an orientation-free use of the sensor. We also propose a correction algorithm to increase the accuracy when used in free living conditions and a battery saving algorithm to consume less power without reducing performance. Our experimental results show that the proposed system can adequately recognize each activity, yielding better accuracy in the detection of bus and subway activities than existing methods.

Smartphone Location-Independent Physical Activity Recognition Based on Transportation Natural Vibration Analysis

PubMed Central

Hur, Taeho; Bang, Jaehun; Kim, Dohyeong; Banos, Oresti; Lee, Sungyoung

2017-01-01

Activity recognition through smartphones has been proposed for a variety of applications. The orientation of the smartphone has a significant effect on the recognition accuracy; thus, researchers generally propose using features invariant to orientation or displacement to achieve this goal. However, those features reduce the capability of the recognition system to differentiate among some specific commuting activities (e.g., bus and subway) that normally involve similar postures. In this work, we recognize those activities by analyzing the vibrations of the vehicle in which the user is traveling. We extract natural vibration features of buses and subways to distinguish between them and address the confusion that can arise because the activities are both static in terms of user movement. We use the gyroscope to fix the accelerometer to the direction of gravity to achieve an orientation-free use of the sensor. We also propose a correction algorithm to increase the accuracy when used in free living conditions and a battery saving algorithm to consume less power without reducing performance. Our experimental results show that the proposed system can adequately recognize each activity, yielding better accuracy in the detection of bus and subway activities than existing methods. PMID:28441743

Tunnel Point Cloud Filtering Method Based on Elliptic Cylindrical Model

NASA Astrophysics Data System (ADS)

Zhua, Ningning; Jiaa, Yonghong; Luo, Lun

2016-06-01

The large number of bolts and screws that attached to the subway shield ring plates, along with the great amount of accessories of metal stents and electrical equipments mounted on the tunnel walls, make the laser point cloud data include lots of non-tunnel section points (hereinafter referred to as non-points), therefore affecting the accuracy for modeling and deformation monitoring. This paper proposed a filtering method for the point cloud based on the elliptic cylindrical model. The original laser point cloud data was firstly projected onto a horizontal plane, and a searching algorithm was given to extract the edging points of both sides, which were used further to fit the tunnel central axis. Along the axis the point cloud was segmented regionally, and then fitted as smooth elliptic cylindrical surface by means of iteration. This processing enabled the automatic filtering of those inner wall non-points. Experiments of two groups showed coincident results, that the elliptic cylindrical model based method could effectively filter out the non-points, and meet the accuracy requirements for subway deformation monitoring. The method provides a new mode for the periodic monitoring of tunnel sections all-around deformation in subways routine operation and maintenance.

Sciencetogo.Org: Using Humor to Engage a Public Audience with the Serious Issue of Climate Change

NASA Astrophysics Data System (ADS)

Lustick, D. S.; Lohmeier, J.; Chen, R. F.; Rabkin, D.; Wilson, R.

2014-12-01

A team of educators, scientists, and communication experts from multiple universities as well as a Science museum will report on the impact of ScienceToGo.org, which is an Out of Home Multi-Media (OHMM) exhibit targeting adults riding a major subway system. The campaign's goal is to design, implement, and study the efficacy of an OHMM model for free choice science learning about our changing climate. Subway riders represent a diverse and captive audience with most of them spending an average of one hour a day in the subway system. Through the use of specially designed OHMM such as train placards, platform posters, and virtual resources the campaign engages a potential audience of 500,000 riders/day with opportunities to learn climate change science informally. The primary goal of the ScienceToGo.org campaign is to engage, entertain, and educate the adult subway riding community in major U.S. city about climate change as a real, relevant, and solvable local challenge. A naturalistic quasi-experimental inquiry employing a mixed methodology approach best describes our research design with half of the subway system exposed to the project signage (experimental group) and the other half not being exposed to the project signage (control group). To identify possible outcomes, data was collected in the several forms: survey, analytic data associated with website, social media, web app, focus groups, and observations. This campaign is an example of how an individual's daily routine may be enhanced with an informal science learning opportunity. We see an urgent need to improve both the public's engagement with climate change science and to the profile of climate change science in formal education settings. The campaign makes deliberate use of humor and fun to engage a public and diverse audience with the serious issue of climate change. The research that will be presented will reveal some of the strengths and weaknesses of this strategy when communicating science to a diverse audience. Overall, the preponderance of evidence indicates that humor and fun are effective at engaging riders on mass transit. Mass transit spaces represent a promsing medium for further exploration and development when it comes to informal learning about climate change science.

Comparison of Personal PM2.5 Exposure in Various Micro-Environments during Haze and Clean Days in Nanjing

NASA Astrophysics Data System (ADS)

Zhang, T.

2015-12-01

There is a long term trend of haze in East China. As a main component of haze, fine particle (PM2.5) in various micro-environments (MEs) is a cause for concern regarding the environment and public health. To estimate individual PM2.5 exposures in distinct, non-residential MEs and to determine exposure characteristics during haze and clean days, we conducted personal PM2.5 monitoring with portable PM2.5 personal environment monitors (MicroPEM) in 19 indoor/outdoor MEs in Nanjing, and compared personal exposure data with ambient PM2.5 levels. Personal PM2.5 exposure patterns displayed notable spatial variance, peaking in snack streets and restaurants and dipping in subways and labs. Under both haze and non-haze conditions, different characteristics of MEs and the background PM2.5 level jointly determine the spatial variance of individual exposure. Indoor MEs with better ventilation systems led to lower personal PM2.5 exposure levels. During haze days, impact from high ambient PM2.5 overwhelms influence from other factors and dominates personal exposure trends.

Measurement of vibrations at different sections of rail through fiber optic sensors

NASA Astrophysics Data System (ADS)

Barreda, A.; Molina-Jiménez, T.; Valero, E.; Recuero, S.

2011-09-01

This paper presents the results of an investigation about how the vibration of railway vehicles affects nearby buildings. The overall objective is to study the vibration generated in urban environments by tram, train and subway, its transmission to the ground and how the buildings and constructions of the environment receive them. Vibrations can generate noise and vibrations in buildings. For this reason it is necessary to characterize the level of vibration affecting rail, road infrastructure and sidewalks and nearby buildings, to assess the influence of the train (speed, type, profile wheel ,..), rail (area of rolling) and route of step, and finally define interim corrective measures. In this study measurements of levels of energy and vibration excitation frequencies will be undertaken through optical techniques: optical fiber networks with distributed Bragg sensors. Measuring these vibrations in different configurations allows us to evaluate the suitability of different sections of rail for different types of uses or environments. This study aims to help improve the safety of the built environment in the vicinity of a railway operation, and thus increase the comfort for passengers and to reduce the environmental impact.

Multiplex networks in metropolitan areas: generic features and local effects.

PubMed

Strano, Emanuele; Shai, Saray; Dobson, Simon; Barthelemy, Marc

2015-10-06

Most large cities are spanned by more than one transportation system. These different modes of transport have usually been studied separately: it is however important to understand the impact on urban systems of coupling different modes and we report in this paper an empirical analysis of the coupling between the street network and the subway for the two large metropolitan areas of London and New York. We observe a similar behaviour for network quantities related to quickest paths suggesting the existence of generic mechanisms operating beyond the local peculiarities of the specific cities studied. An analysis of the betweenness centrality distribution shows that the introduction of underground networks operate as a decentralizing force creating congestion in places located at the end of underground lines. Also, we find that increasing the speed of subways is not always beneficial and may lead to unwanted uneven spatial distributions of accessibility. In fact, for London—but not for New York—there is an optimal subway speed in terms of global congestion. These results show that it is crucial to consider the full, multimodal, multilayer network aspects of transportation systems in order to understand the behaviour of cities and to avoid possible negative side-effects of urban planning decisions. © 2015 The Author(s).

Multiplex networks in metropolitan areas: generic features and local effects

PubMed Central

Strano, Emanuele; Shai, Saray; Dobson, Simon; Barthelemy, Marc

2015-01-01

Most large cities are spanned by more than one transportation system. These different modes of transport have usually been studied separately: it is however important to understand the impact on urban systems of coupling different modes and we report in this paper an empirical analysis of the coupling between the street network and the subway for the two large metropolitan areas of London and New York. We observe a similar behaviour for network quantities related to quickest paths suggesting the existence of generic mechanisms operating beyond the local peculiarities of the specific cities studied. An analysis of the betweenness centrality distribution shows that the introduction of underground networks operate as a decentralizing force creating congestion in places located at the end of underground lines. Also, we find that increasing the speed of subways is not always beneficial and may lead to unwanted uneven spatial distributions of accessibility. In fact, for London—but not for New York—there is an optimal subway speed in terms of global congestion. These results show that it is crucial to consider the full, multimodal, multilayer network aspects of transportation systems in order to understand the behaviour of cities and to avoid possible negative side-effects of urban planning decisions. PMID:26400198

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.

An understanding of human dynamics in urban subway traffic from the Maximum Entropy Principle

NASA Astrophysics Data System (ADS)

Yong, Nuo; Ni, Shunjiang; Shen, Shifei; Ji, Xuewei

2016-08-01

We studied the distribution of entry time interval in Beijing subway traffic by analyzing the smart card transaction data, and then deduced the probability distribution function of entry time interval based on the Maximum Entropy Principle. Both theoretical derivation and data statistics indicated that the entry time interval obeys power-law distribution with an exponential cutoff. In addition, we pointed out the constraint conditions for the distribution form and discussed how the constraints affect the distribution function. It is speculated that for bursts and heavy tails in human dynamics, when the fitted power exponent is less than 1.0, it cannot be a pure power-law distribution, but with an exponential cutoff, which may be ignored in the previous studies.

Public transit research: Rail, bus, and new technology, 1991. Transportation Research Record

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

Kassabian, N.C.; Tobias, A.G.; Crayton, L.

1991-01-01

The report contains: Image of Rail Transit; Train Operations Computer Simulation Case Study: Single-Tracking Operations for Philadelphia's Market-Frankford Subway Elevated Rail Rapid Transit Line; Transit Railcar Quantities: Scale Economies; Evaluation of Training Programs in Rail Transit: Its Role and Status; Methodology for Evaluating Out-of-Direction Bus Route Segments; Integration of Fixed- and Flexible-Route Bus Systems; Downtown Space for Buses--The Manhattan Experience; Implications of Transit Drug Testing and Maintenance Service Procurement for Small Urban and Rural Systems; Challenges for Integration of Alternative Fuels in the Transit Industry; Short History of the Transbay Transit Terminal and the Relocation of the San Francisco Greyhoundmore » Depot Thereto; Airport Development with Automated People Mover Systems; Review of Four Alternative Airport Terminal Passenger Mobility Systems.« less

Progress in Application of Generalized Wigner Distribution to Growth and Other Problems

NASA Astrophysics Data System (ADS)

Einstein, T. L.; Morales-Cifuentes, Josue; Pimpinelli, Alberto; Gonzalez, Diego Luis

We recap the use of the (single-parameter) Generalized Wigner Distribution (GWD) to analyze capture-zone distributions associated with submonolayer epitaxial growth. We discuss recent applications to physical systems, as well as key simulations. We pay particular attention to how this method compares with other methods to assess the critical nucleus size characterizing growth. The following talk discusses a particular case when special insight is needed to reconcile the various methods. We discuss improvements that can be achieved by going to a 2-parameter fragmentation approach. At a much larger scale we have applied this approach to various distributions in socio-political phenomena (areas of secondary administrative units [e.g., counties] and distributions of subway stations). Work at UMD supported by NSF CHE 13-05892.

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.

Characteristics of PM10 and CO2 concentrations on 100 underground subway station platforms in 2014 and 2015

NASA Astrophysics Data System (ADS)

Hwang, Sung Ho; Park, Wha Me; Park, Jae Bum; Nam, Taegyun

2017-10-01

In this study, the concentrations of particulate matter 10 μm or less in diameter (PM10) and carbon dioxide (CO2) were measured in 100 underground subway stations, and the potential health risks of PM10, and environmental factors affecting these concentrations were analyzed. The concentrations were measured from May 2014 to September 2015 in stations along Seoul Metro lines 1-4. There were significantly different PM10 concentrations among the underground subway stations along lines 1, 2, 3, and 4. The PM10 concentrations were associated with the CO2 concentrations, construction years, station depths, and numbers of passengers. The underground PM10 concentrations were significantly higher than the outdoor PM10 concentrations. In addition, the PM10 concentrations were higher in the stations that were constructed in the 1970s than in those constructed after the 1970s. The PM10 and CO2 concentrations varied significantly, depending on the construction year and number of passengers. The hazard quotient is higher than the acceptable level of 1.0 μg kg-1 day for children, indicating that they are at risk of exposure to unsafe PM10 levels when travelling by the metro. Therefore, stricter management may be necessary for the stations constructed in the 1970s as well as those with higher numbers of passengers.

Radon and NO2 levels and related environmental factors in 100 underground subway platforms over two-year period.

PubMed

Hwang, Sung Ho; Park, Jae Bum; Park, Wha Me

2018-01-01

In this study, the environmental factors that affect radon (Rn) and nitrogen dioxide (NO 2 ) levels in subway-station underground platforms are evaluated, and the outdoor NO 2 levels are compared with those obtained for the underground platforms. The Rn and NO 2 levels from May 2013 to September 2015 are determined for lines 1-4 of the Seoul Metro, via calculation of the arithmetic means of the Rn and NO 2 levels with their standard deviations (SDs). The underground Rn levels in 2013 are found to be significantly higher than those recorded in 2015 for the Seoul Metro. In addition, the Rn levels are related to the station depth and construction year. Further, the underground NO 2 levels are shown to be significantly higher than the outdoor levels for all four Seoul Metro subway lines. The Rn levels are also found to vary significantly between months, and are shown to increase gradually with depth from 8 to 20 m. The Rn levels are also higher for stations constructed in the 1980s. Therefore, stricter monitoring of Rn level may be required for stations constructed in the 1980s and/or having platform depths within the 8-20 m range. Island-type platform stations based on granite areas may also require careful attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

Problems of increased transport load as a result of implementation of projects of high-rise constructions

NASA Astrophysics Data System (ADS)

Provotorov, Ivan; Gasilov, Valentin; Anisimova, Nadezhda

2018-03-01

The structure of problems of high-rise construction us suggested, which includes the impact on environment, design solutions, transportation problems, financial costs for construction and operation, and others. Positive and negative aspects of high-rise construction are considered. One of the basic problems of high-rise construction is the problem of increased transport load. Construction of the subway on the basis of the concession mechanism, with the use of unmanned control of rolling stock is proposed as the most expedient solution. An evaluation of the effectiveness of this project is presented, it shows quite high performance indicators for a private investor. Main problems that the project implementation may face in conditions of lack of scientific and methodological support are outlined.

Structure-borne noise at hotels

NASA Astrophysics Data System (ADS)

Wilson, George Paul; Jue, Deborah A.

2002-11-01

Hotels present a challenging environment for building designers to provide suitable noise and vibration isolation between very incompatible uses. While many are familiar with ways to reduce traditional sources of airborne noise and vibration, structure-borne noise and vibration are often overlooked, often with costly repercussions. Structure-borne noise can be very difficult to pinpoint, and troubleshooting the sources of the vibration can be a tedious process. Therefore, the best approach is to avoid the problem altogether during design, with attention to the building construction, potential vibration sources, building uses and equipment locations. In this paper, the relationship between structure-borne vibration and noise are reviewed, typical vibration sources discussed (e.g., aerobic rooms, laundry rooms, mechanical equipment/building services, and subway rail transit), and key details and design guidance to minimize structure-borne noise provided.

Physiological responses and air consumption during simulated firefighting tasks in a subway system.

PubMed

Williams-Bell, F Michael; Boisseau, Geoff; McGill, John; Kostiuk, Andrew; Hughson, Richard L

2010-10-01

Professional firefighters (33 men, 3 women), ranging in age from 30 to 53 years, participated in a simulation of a subway system search and rescue while breathing from their self-contained breathing apparatus (SCBA). We tested the hypothesis that during this task, established by expert firefighters to be of moderate intensity, the rate of air consumption would exceed the capacity of a nominal 30-min cylinder. Oxygen uptake, carbon dioxide output, and air consumption were measured with a portable breath-by-breath gas exchange analysis system, which was fully integrated with the expired port of the SCBA. The task involved descending a flight of stairs, walking, performing a search and rescue, retreat walking, then ascending a single flight of stairs to a safe exit. This scenario required between 9:56 and 13:24 min:s (mean, 12:10 ± 1:10 min:s) to complete, with an average oxygen uptake of 24.3 ± 4.5 mL kg(-1) min(-1) (47 ± 10 % peak oxygen uptake) and heart rate of 76% ± 7% of maximum. The highest energy requirement was during the final single-flight stair climb (30.4 ± 5.4 mL kg(-1) min(-1)). The average respiratory exchange ratio (carbon dioxide output/oxygen uptake) throughout the scenario was 0.95 ± 0.08, indicating a high carbon dioxide output for a relatively moderate average energy requirement. Air consumption from the nominal "30-min" cylinder averaged 51% (range, 26%-68%); however, extrapolation of these rates of consumption suggested that the low-air alarm, signalling that only 25% of the air remains, would have occurred as early as 11 min for an individual with the highest rate of air consumption, and at 16 min for the group average. These data suggest that even the moderate physical demands of walking combined with search and rescue while wearing full protective gear and breathing through the SCBA impose considerable physiological strain on professional firefighters. As well, the rate of air consumption in these tasks classed as moderate, compared with high-rise firefighting, would have depleted the air supply well before the nominal time used to describe the cylinders.

Use of a 10.22 m diameter EPB shield: a case study in Beijing subway construction.

PubMed

Li, Xinggao; Yuan, Dajun; Guo, Yuhai; Cai, Zhiyong

2016-01-01

Beijing subway line 14 includes four stations and approximately 2.8 km of tunnels between the Dongfengbeiqiao and Jingshunlu areas of the city. Due to the surface and underground space limitations of this section, a double-track running tunnel instead of two single-track running tunnels was adopted to connect the two stations. The double-track tunnels were excavated by a 10.22 m diameter earth pressure balance (EPB) shield. It was the first time that an EPB shield more than 10 m in diameter was used in Beijing subway construction. The shield, which passes underneath densely built-up areas of the city and is equipped with a spoke-type cutterhead, with balance between the ground pressure and the earth chamber pressure at the tunnel face, is of great importance. Referring to experiences gained in the EPB shield tunneling, attention was paid to the function of soil conditioning and simultaneous backfilling grouting of the shield, and some special designs were considered in manufacturing the machine. In addition to the agitating rods welded to the cutterhead, two independently driven agitators were added to fully mix everything in the earth chamber. Independent pipelines were arranged for injecting different conditioning agents. Indoor tests in combination with field tests were conducted to find suitable additives and injection ratios of the additives, and determine the mix ratio of the two-component grout for simultaneous backfilling grouting. A scheme was employed for simultaneously injecting the bentonite slurry at 8% concentration and the foam liquid at 5% concentration to condition the excavated soil. The cement-sodium silicate grout was adopted to fill the tail void and the injection volume per ring was 14.1-15.3 m 3 . The performance of the shield and evaluation of the corresponding tunneling technologies are introduced in terms of the shield tunneling induced ground surface settlements. The success of the project is of great significance to Beijing subway construction and underground space utilization. The findings serve as a useful reference for similar projects.

Driving When You Have Cataracts

MedlinePlus

... cabs; N shuttle buses or vans; and N public buses, trains and subways. I Also, senior centers, religious and other local service groups often offer transportation services for older adults in your community. Who ...

Life Outside NCI | Cancer Prevention Fellowship Program

Cancer.gov

The CPFP Office is located at the NCI facilities in Rockville, Maryland, near the Nation’s Capital. With the convenient Metro subway reaching throughout the metropolitan area, transportation is within easy reach.

Underground Transport Restoration (UTR) Operational Technology Demonstration (OTD)

EPA Pesticide Factsheets

This full-scale study focused on gathering sampling, decontamination (decon), waste management, and cost analysis information for the remediation of a subway system after contamination with a Bacillus anthracis (Ba) surrogate.

A simulation study of the impact of the public-private partnership strategy on the performance of transport infrastructure.

PubMed

Huang, Zhengfeng; Zheng, Pengjun; Ma, Yanqiang; Li, Xuan; Xu, Wenjun; Zhu, Wanlu

2016-01-01

The choice of investment strategy has a great impact on the performance of transport infrastructure. Positive projects such as the "Subway plus Property" model in Hong Kong have created sustainable financial profits for the public transport projects. Owing to a series of public debt and other constraints, public-private partnership (PPP) was introduced as an innovative investment model to address this issue and help develop transport infrastructure. Yet, few studies provide a deeper understanding of relationships between PPP strategy and the performance of such transport projects (particularly the whole transport system). This paper defines the research scope as a regional network of freeway. With a popular PPP model, travel demand prediction method, and relevant parameters as input, agents in a simulation framework can simulate the choice of PPP freeway over time. The simulation framework can be used to analyze the relationship between the PPP strategy and performance of the regional freeway network. This study uses the Freeway Network of Yangtze River Delta (FN-YRD) in China as the context. The results demonstrate the value of using simulation models of complex transportation systems to help decision makers choose the right PPP projects. Such a tool is viewed as particularly important given the ongoing transformation of functions of the Chinese transportation sector, including franchise rights of transport projects, and freeway charging mechanism.

The West Beverly Hills Lineament and Beverly Hills High School: Ethical Issues in Geo-Hazard Communication

NASA Astrophysics Data System (ADS)

Gath, Eldon; Gonzalez, Tania; Roe, Joe; Buchiarelli, Philip; Kenny, Miles

2014-05-01

Results of geotechnical studies for the Westside Subway were disclosed in a public hearing on Oct. 19, 2011, showing new "active faults" of the Santa Monica fault and the West Beverly Hills Lineament (WBHL), identified as a northern extension of the Newport-Inglewood fault. Presentations made spoke of the danger posed by these faults, the possibility of killing people, and how it was good news that these faults had been discovered now instead of later. The presentations were live and are now memorialized as YouTube videos, (http://www.youtube.com/watch?v=Omx2BTIpzAk and others). No faults had been physically exposed or observed by the study; the faults were all interpreted from cone penetrometer probes, supplemented by core borings and geophysical transects. Several of the WBHL faults traversed buildings of the Beverly Hills High School (BHHS), triggering the school district to geologically map and characterize these faults for future planning efforts, and to quantify risk to the students in the 1920's high school building. 5 exploratory trenches were excavated within the high school property, 12 cone penetrometers were pushed, and 26-cored borings were drilled. Geologic logging of the trenches and borings and interpretation of the CPT data failed to confirm the presence of the mapped WBHL faults, instead showing an unfaulted, 3° NE dipping sequence of mid-Pleistocene alluvial fan deposits conformably overlying an ~1 Ma marine sand. Using 14C, OSL, and soil pedology for stratigraphic dating, the BHHS site was cleared from fault rupture hazards and the WBHL was shown to be an erosional margin of Benedict Canyon, partially buttressed by 40-200 ka alluvial deposits from Benedict Wash. The consequence of the Westside Subway's active fault maps has been the unexpected expenditure of millions of dollars for emergency fault investigations at BHHS and several other private properties within a densely developed urban highrise environment. None of these studies have found any active faults where they had been interpreted, mapped, and published by the subway's consultants. Litigation is underway by the affected parties to recoup their geological expenditures and recover costs for lost business revenues. Even had the active fault map been correct, its public release was poorly managed. That the released active fault map has now been found to be badly in error poses more significant ethical issues about hazard communication and likely legal consequences.

Insurance for Urban Transportation Construction

DOT National Transportation Integrated Search

1977-06-01

This report investigates insurance programs for urban transportation construction, including subways, and establishes guidelines by which an authority owner can choose the insurance program which best serves the needs dictated by the conditions and f...

Find a Support Group (Brain Tumor)

MedlinePlus

... seek support. Located in the heart of Union Square and easily accessible by the 4,5,6, ... subway lines. Meeting location: Mount Sinai Downtown Union Square, 10 Union Square East, 5th floor, Conference Room ...

Questions raised about benefits of artificial reefs

NASA Astrophysics Data System (ADS)

Showstack, Randy

Twenty-seven subway cars lined on a barge awaited their fate off the coast of Delaware, about 26 kilometers east of the Indian River Inlet, on August 22.A priest blessed the dark-red cars donated by the New York City Transit Authority, and prayed for the safety of all creatures using them. The song, “Sidewalks of New York” filled the festivities: “East side, west side, all around the town…” A woman tossed tokens from those subway lines into the sea. Then, down went the cars, having first been scrubbed clean, with windows removed for better circulation. Shoved by a bulldozer, the cars were deployed in 35 minutes to join a heap of military vehicles, old tires, and other used materials already accumulated at Reef Site 11, a 1.3-square-nautical-mile artificial reef.

Has successful terror gone to ground?

PubMed

Barnett, Arnold

2015-04-01

This article considers all 87 attacks worldwide against air and rail transport systems that killed at least two passengers over the 30-year period of 1982-2011. The data offer strong and statistically significant evidence that successful acts of terror have "gone to ground" in recent years: attacks against aviation were concentrated early in the three decades studied whereas those against rail were concentrated later. Recent data are used to make estimates of absolute and comparative risk for frequent flyers and subway/rail commuters. Point estimates in the "status quo" case imply that mortality risk from successful acts of terror was very low on both modes of transportation and that, whereas risk per trip is higher for air travelers than subway/rail commuters, the rail commuters experience greater risk per year than the frequent flyers. © 2015 Society for Risk Analysis.

Preferred listening levels of mobile phone programs when considering subway interior noise

PubMed Central

Yu, Jyaehyoung; Lee, Donguk; Han, Woojae

2016-01-01

Today, people listen to music loud using personal listening devices. Although a majority of studies have reported that the high volume played on these listening devices produces a latent risk of hearing problems, there is a lack of studies on “double noise exposures” such as environmental noise plus recreational noise. The present study measures the preferred listening levels of a mobile phone program with subway interior noise for 74 normal-hearing participants in five age groups (ranging from 20s to 60s). The speakers presented the subway interior noise at 73.45 dB, while each subject listened to three application programs [Digital Multimedia Broadcasting (DMB), music, game] for 30 min using a tablet personal computer with an earphone. The participants’ earphone volume levels were analyzed using a sound level meter and a 2cc coupler. Overall, the results showed that those in their 20s listened to the three programs significantly louder with DMB set at significantly higher volume levels than for the other programs. Higher volume levels were needed for middle frequency compared to the lower and higher frequencies. We concluded that any potential risk of noise-induced hearing loss for mobile phone users should be communicated when users listen regularly, although the volume level was not high enough that the users felt uncomfortable. When considering individual listening habits on mobile phones, further study to predict total accumulated environmental noise is still needed. PMID:26780960

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.

Preferred listening levels of mobile phone programs when considering subway interior noise.

PubMed

Yu, Jyaehyoung; Lee, Donguk; Han, Woojae

2016-01-01

Today, people listen to music loud using personal listening devices. Although a majority of studies have reported that the high volume played on these listening devices produces a latent risk of hearing problems, there is a lack of studies on "double noise exposures" such as environmental noise plus recreational noise. The present study measures the preferred listening levels of a mobile phone program with subway interior noise for 74 normal-hearing participants in five age groups (ranging from 20s to 60s). The speakers presented the subway interior noise at 73.45 dB, while each subject listened to three application programs [Digital Multimedia Broadcasting (DMB), music, game] for 30 min using a tablet personal computer with an earphone. The participants' earphone volume levels were analyzed using a sound level meter and a 2cc coupler. Overall, the results showed that those in their 20s listened to the three programs significantly louder with DMB set at significantly higher volume levels than for the other programs. Higher volume levels were needed for middle frequency compared to the lower and higher frequencies. We concluded that any potential risk of noise-induced hearing loss for mobile phone users should be communicated when users listen regularly, although the volume level was not high enough that the users felt uncomfortable. When considering individual listening habits on mobile phones, further study to predict total accumulated environmental noise is still needed.

Violence in Advertisements in New York City Subway Stations: A Pilot Study.

PubMed

Basch, Corey H; Fullwood, M D; LeBlanc, Michael

2016-04-01

Violence has become a public health concern in the United States. Violent visually stimulating content encompasses various techniques such as fear, humor, shock, or violence, to stimulate a response or appeal toward awareness of human emotion. Exposing impressionable youth to violent advertisements can be particularly problematic. This is especially true in places like New York City where violent crime is a prevalent problem. With annual ridership reaching over 1.7 billion in 2014, the New York City subway system is abundant with advertisements. The purpose of this pilot study was to determine the frequency and type of violent advertising on the Lexington Avenue/East Side Line in New York City, running through the Bronx and Manhattan to represent the lower and higher median income earning boroughs. There were no statistically different findings in median household income at site of station by number of ads or source of violent. Destruction was the most common form of violence (n = 32, 42.7 %) followed by intent to strike (n = 18, 24 %), showing a weapon (n = 15, 20 %) and horror (n = 10, 13.3 %). Most ads (n = 46, 61.3 %) were found in stations heading uptown toward and through the Bronx, the borough where median household income is lowest, whereas 29 (38.7 %) were found in stations heading downtown. Future studies could focus on additional boroughs and subways lines, and could be collected at multiple points in time to determine of how prevalent violent advertising is throughout New York City and at different time frames.

Source apportionment of indoor, outdoor and personal PM2.5 exposure of pregnant women in Barcelona, Spain

NASA Astrophysics Data System (ADS)

Minguillón, M. C.; Schembari, A.; Triguero-Mas, M.; de Nazelle, A.; Dadvand, P.; Figueras, F.; Salvado, J. A.; Grimalt, J. O.; Nieuwenhuijsen, M.; Querol, X.

2012-11-01

Exposure to air pollution has been shown to adversely affect foetal development in the case of pregnant women. The present study aims to investigate the PM composition and sources influencing personal exposure of pregnant women in Barcelona. To this end, indoor, outdoor and personal exposure measurements were carried out for a selection of 54 pregnant women between November 2008 and November 2009. PM2.5 samples were collected during two consecutive days and then analysed for black smoke (BS), major and trace elements, and polycyclic aromatic hydrocarbons (PAHs) concentrations. Personal information such as commuting patterns and cosmetics use was also collected. PM2.5 concentrations were higher for personal samples than for indoor and outdoor environments. Indoor, outdoor and personal BS and sulphate concentrations were strongly correlated, although some specific indoor and outdoor sulphate sources may exist. Average trace elements concentrations were similar indoor, outdoor and for personal exposure, but the correlations were moderate for most of them. Most of the PAHs concentrations showed strong correlations indoor-outdoor. A source apportionment analysis of the PM composition data by means of a Positive Matrix Factorization (PMF) resulted in the identification of six sources for the outdoor and indoor environments: secondary sulphate, fueloil + sea salt (characterized by V, Ni, Na and Mg), mineral, cigarette (characterized by K, Ce, Cd, benzo(k)fluoranthene and benzo(ghi)perylene), road traffic (characterized by BS and low weight PAHs), and industrial (characterized by Pb, Sn, Cu, Mn and Fe). For personal exposure two specific sources were found: cosmetics (characterized by abundance of Ca, Li, Ti and Sr and the absence of Al) and train/subway (characterized by Fe, Mn, Cu and Ba). The contribution of the sources varied widely among women, especially for cigarette (from zero to up to 4 μg m-3), train/subway (up to more than 6 μg m-3) and cosmetics (up to more than 5 μg m-3). The source contributions showed generally strong correlations indoor-outdoor although the infiltration efficiencies varied among homes. This study emphasizes the importance of relying on personal exposure in epidemiological studies assessing the impact of air pollution on human health.

New York Polytechnic: Tiffany of Subway Schools

ERIC Educational Resources Information Center

Bard, Bernard

1975-01-01

Through intensive student recruitment, faculty planning, new undergraduate programs and acquisitioning of research and endowment money PINY, previously close to bankruptcy, is now approaching its goal of becoming the great technological university of New York. (KE)

Retail redlining in New York City: racialized access to day-to-day retail resources.

PubMed

Kwate, Naa Oyo A; Loh, Ji Meng; White, Kellee; Saldana, Nelson

2013-08-01

Racial residential segregation is associated with health inequalities in the USA, and one of the primary mechanisms is through influencing features of the neighborhood physical environment. To better understand how Black residential segregation might contribute to health risk, we examined retail redlining; the inequitable distribution of retail resources across racially distinct areas. A combination of visual and analytic methods was used to investigate whether predominantly Black census block groups in New York City had poor access to retail stores important for health. After controlling for retail demand, median household income, population density, and subway ridership, percent Black was associated with longer travel distances to various retail industries. Our findings suggest that Black neighborhoods in New York City face retail redlining. Future research is needed to determine how retail redlining may perpetuate health disparities and socioeconomic disadvantage.

A Probabilistic Risk Assessment of Groundwater-Related Risks at Excavation Sites

NASA Astrophysics Data System (ADS)

Jurado, A.; de Gaspari, F.; Vilarrasa, V.; Sanchez-Vila, X.; Fernandez-Garcia, D.; Tartakovsky, D. M.; Bolster, D.

2010-12-01

Excavation sites such as those associated with the construction of subway lines, railways and highway tunnels are hazardous places, posing risks to workers, machinery and surrounding buildings. Many of these risks can be groundwater related. In this work we develop a general framework based on a probabilistic risk assessment (PRA) to quantify such risks. This approach is compatible with standard PRA practices and it employs many well-developed risk analysis tools, such as fault trees. The novelty and computational challenges of the proposed approach stem from the reliance on stochastic differential equations, rather than reliability databases, to compute the probabilities of basic events. The general framework is applied to a specific case study in Spain. It is used to estimate and minimize risks for a potential construction site of an underground station for the new subway line in the Barcelona metropolitan area.

RESEARCH INTO PSYCHOLOGICAL EVALUATION METHOD OF UNDERGROUND SPACE - CENTERING ON THE TOKYO METRO -

NASA Astrophysics Data System (ADS)

Yoshimoto, Naomi; Wake, Tenji; Mita, Takeshi; Wake, Hiromi

This research is concerned with developing evaluation methods that can be useful for environmental design from the psychological perspective of QOL, that is comfort, in underground space. For this research, eight stations on the Tokyo Metro, including the Fukutoshin line, were selected and two types of questionnaires were carried out after respondents had walked through the station areas and the walkways connecting the stations. From the results of the first questionnaire, four factors, comfort/convenience, insecurity, visibility/noticeability, brightness/ease of walking, were extracted. From the results of the second questionnaire, three factors were extracted: visibility of noticeboards, overall atmosphere of underground space, visibility of fare chart/subway map. There was a strong correlation between the factors comfort/convenience and insecurity, extracted from the first questionnaire, and the overall atmosphere factor extracted from the second questionnaire. For visibility/noticeability, there was a strong correlation with notices, fares chart, and subway map.

[Recruitment of smokers in the Rio de Janeiro subway, Brazil, as a strategy to increase access to quitline services: the impact of novelty].

PubMed

Szklo, André Salem; Coutinho, Evandro da Silva Freire; Barros, Helena Maria Tannhauser; Perez, Cristina; Moreira, Taís de Campos; Figueiró, Luciana Rizzieri; Pinho, Mariana; Carvalho, Valeska Figueiredo

2009-11-01

Creative and innovative strategies to recruit smokers are essential for improving tobacco control activities. Currently in Brazil, through health warning messages on cigarette packs, there is a permanent and intense spread of messages that provoke feelings of loss associated with smoking, which is important to encourage access to smoking quitlines. The study analyzed the call rate for telephone counseling after introducing a new strategy for reactive recruitment focused on the theme 'smoking causes shortness of breath', adapted to the subway setting in Rio de Janeiro, as compared to the rates for two existing reactive strategies. Regardless of age bracket, there was a higher response to the new proposed strategy. Despite the major awareness-raising in Brazil concerning the ills of tobacco, new communications formats approaching personally relevant themes can increase the number and range of smokers recruited for telephone counseling to support cessation.

Numerical Calculation Method for Prediction of Ground-borne Vibration near Subway Tunnel

NASA Astrophysics Data System (ADS)

Tsuno, Kiwamu; Furuta, Masaru; Abe, Kazuhisa

This paper describes the development of prediction method for ground-borne vibration from railway tunnels. Field measurement was carried out both in a subway shield tunnel, in the ground and on the ground surface. The generated vibration in the tunnel was calculated by means of the train/track/tunnel interaction model and was compared with the measurement results. On the other hand, wave propagation in the ground was calculated utilizing the empirical model, which was proposed based on the relationship between frequency and material damping coefficient α in order to predict the attenuation in the ground in consideration of frequency characteristics. Numerical calculation using 2-dimensinal FE analysis was also carried out in this research. The comparison between calculated and measured results shows that the prediction method including the model for train/track/tunnel interaction and that for wave propagation is applicable to the prediction of train-induced vibration propagated from railway tunnel.

Removal of particulate matter emitted from a subway tunnel using magnetic filters.

PubMed

Son, Youn-Suk; Dinh, Trieu-Vuong; Chung, Sang-Gwi; Lee, Jai-Hyo; Kim, Jo-Chun

2014-01-01

We removed particulate matter (PM) emitted from a subway tunnel using magnetic filters. A magnetic filter system was installed on the top of a ventilation opening. Magnetic field density was increased by increasing the number of permanent magnet layers to determine PM removal characteristics. Moreover, the fan's frequency was adjusted from 30 to 60 Hz to investigate the effect of wind velocity on PM removal efficiency. As a result, PM removal efficiency increased as the number of magnetic filters or fan frequency increased. We obtained maximum removal efficiency of PM10 (52%), PM2.5 (46%), and PM1 (38%) at a 60 Hz fan frequency using double magnetic filters. We also found that the stability of the PM removal efficiency by the double filter (RSD, 3.2-5.8%) was higher than that by a single filter (10.9-24.5%) at all fan operating conditions.

Probabilistic Risk Analysis of Groundwater Related Problems in Subterranean Excavation Sites

NASA Astrophysics Data System (ADS)

Sanchez-Vila, X.; Jurado, A.; de Gaspari, F.; Vilarrasa, V.; Bolster, D.; Fernandez-Garcia, D.; Tartakovsky, D. M.

2009-12-01

Construction of subterranean excavations in densely populated areas is inherently hazardous. The number of construction sites (e.g., subway lines, railways and highway tunnels) has increased in recent years. These sites can pose risks to workers at the site as well as cause damage to surrounding buildings. The presence of groundwater makes the excavation even more complicated. We develop a probabilistic risk assessment (PRA) model o estimate the likelihood of occurrence of certain risks during a subway station construction. While PRA is widely used in many engineering fields, its applications to the underground constructions in general and to an underground station construction in particular are scarce if not nonexistent. This method enables us not only to evaluate the probability of failure, but also to quantify the uncertainty of the different events considered. The risk analysis was carried out using a fault tree analysis that made it possible to study a complex system in a structured and straightforward manner. As an example we consider an underground station for the new subway line in the Barcelona metropolitan area (Línia 9) through the town of Prat de Llobregat in the Llobregat River Delta, which is currently under development. A typical station on the L9 line lies partially between the shallow and the main aquifer. Specifically, it is located in the middle layer which is made up of silts and clays. By presenting this example we aim to illustrate PRA as an effective methodology for estimating and minimising risks and to demonstrate its utility as a potential tool for decision making.

Effects of sarin on the nervous system in rescue team staff members and police officers 3 years after the Tokyo subway sarin attack.

PubMed

Nishiwaki, Y; Maekawa, K; Ogawa, Y; Asukai, N; Minami, M; Omae, K

2001-11-01

Although the clinical manifestations of acute sarin poisoning have been reported in detail, no comprehensive study of the chronic physical and psychiatric effects of acute sarin poisoning has been carried out. To clarify the chronic effects of sarin on the nervous system, a cross-sectional epidemiologic study was conducted 3 years after the Tokyo subway sarin attack. Subjects consisted of the rescue team staff members and police officers who had worked at the disaster site. Subjects consisted of 56 male exposed subjects and 52 referent subjects matched for age and occupation. A neurobehavioral test, stabilometry, and measurement of vibration perception thresholds were performed, as well as psychometric tests to assess traumatic stress symptoms. The exposed group performed less well in the backward digit span test than the referent group in a dose-effect manner. This result was the same after controlling for possible confounding factors and was independent of traumatic stress symptoms. In other tests of memory function, except for the Benton visual retention test (mean correct answers), effects related to exposure were also suggested, although they were not statistically significant. In contrast, the dose-effect relationships observed in the neurobehavioral tests (psychomotor function) were unclear. None of the stabilometry and vibration perception threshold parameters had any relation to exposure. Our findings suggest the chronic decline of memory function 2 years and 10 months to 3 years and 9 months after exposure to sarin in the Tokyo subway attack, and further study is needed.

Effects of sarin on the nervous system in rescue team staff members and police officers 3 years after the Tokyo subway sarin attack.

PubMed Central

Nishiwaki, Y; Maekawa, K; Ogawa, Y; Asukai, N; Minami, M; Omae, K

2001-01-01

Although the clinical manifestations of acute sarin poisoning have been reported in detail, no comprehensive study of the chronic physical and psychiatric effects of acute sarin poisoning has been carried out. To clarify the chronic effects of sarin on the nervous system, a cross-sectional epidemiologic study was conducted 3 years after the Tokyo subway sarin attack. Subjects consisted of the rescue team staff members and police officers who had worked at the disaster site. Subjects consisted of 56 male exposed subjects and 52 referent subjects matched for age and occupation. A neurobehavioral test, stabilometry, and measurement of vibration perception thresholds were performed, as well as psychometric tests to assess traumatic stress symptoms. The exposed group performed less well in the backward digit span test than the referent group in a dose-effect manner. This result was the same after controlling for possible confounding factors and was independent of traumatic stress symptoms. In other tests of memory function, except for the Benton visual retention test (mean correct answers), effects related to exposure were also suggested, although they were not statistically significant. In contrast, the dose-effect relationships observed in the neurobehavioral tests (psychomotor function) were unclear. None of the stabilometry and vibration perception threshold parameters had any relation to exposure. Our findings suggest the chronic decline of memory function 2 years and 10 months to 3 years and 9 months after exposure to sarin in the Tokyo subway attack, and further study is needed. PMID:11713003

Rush-hour aromatic and chlorinated hydrocarbons in selected subway stations of Shanghai, China.

PubMed

Zhang, Yanli; Li, Chunlei; Wang, Xinming; Guo, Hai; Feng, Yanli; Chen, Jianmin

2012-01-01

Air samples were collected simultaneously at platform, mezzanine and outdoor in five typical stations of subway system in Shanghai, China using stainless steel canisters and analyzed by gas chromatography-mass selective detector (GC-MSD) after cryogenic preconcentration. Benzene, toluene, ethylbenzene and xylenes (BTEX) at the platforms and mezzanines inside the stations averaged (10.3 +/- 2.1), (38.7 +/- 9.0), (19.4 +/- 10.1) and (30.0 +/- 11.1) microg/m3, respectively; while trichloroethylene (TrCE), tetrachloroethylene (TeCE) and para-dichlorobenzene (pDCB), vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of (3.6 +/- 1.3), (1.3 +/- 0.5), (4.1 +/- 1.1), (2.2 +/- 1.1) and (1.2 +/- 0.3) microg/m3, respectively. Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O) ratios of 1.1-9.5, whereas no significant indoor/outdoor differences were found except for benzene and TrCE. The highly significant mutual correlations (p < 0.01) for BTEX between indoor and outdoor and their significant correlation (p < 0.05) with methyl tert-butyl ether (MTBE), a marker of traffic-related emission without other indoor and outdoor sources, indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source. TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air, especially in the mezzanines.

Modelling the impact of causal and non-causal factors on disruption duration for Toronto's subway system: An exploratory investigation using hazard modelling.

PubMed

Louie, Jacob; Shalaby, Amer; Habib, Khandker Nurul

2017-01-01

Most investigations of incident-related delay duration in the transportation context are restricted to highway traffic, with little attention given to delays due to transit service disruptions. Studies of transit-based delay duration are also considerably less comprehensive than their highway counterparts with respect to examining the effects of non-causal variables on the delay duration. However, delays due to incidents in public transit service can have serious consequences on the overall urban transportation system due to the pivotal and vital role of public transit. The ability to predict the durations of various types of transit system incidents is indispensable for better management and mitigation of service disruptions. This paper presents a detailed investigation on incident delay durations in Toronto's subway system over the year 2013, focusing on the effects of the incidents' location and time, the train-type involved, and the non-adherence to proper recovery procedures. Accelerated Failure Time (AFT) hazard models are estimated to investigate the relationship between these factors and the resulting delay duration. The empirical investigation reveals that incident types that impact both safety and operations simultaneously generally have longer expected delays than incident types that impact either safety or operations alone. Incidents at interchange stations are cleared faster than incidents at non-interchange stations. Incidents during peak periods have nearly the same delay durations as off-peak incidents. The estimated models are believed to be useful tools in predicting the relative magnitude of incident delay duration for better management of subway operations. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of subway station design on noise levels.

PubMed

Shah, Ravi R; Suen, Jonathan J; Cellum, Ilana P; Spitzer, Jaclyn B; Lalwani, Anil K

2017-05-01

To investigate the impact of subway station design on platform noise levels. Observational. Continuous A-weighted decibel (dBA) sound levels were recorded in 20 New York City subway stations, where trains entered on either a straight track or curved track in 10 stations each. Equivalent continuous noise levels (L eq ) at various locations on the boarding platform (inbound end, midplatform, and outbound end) during train entry and exit were compared between the straight and curved stations in broadband as well as narrow one-third octave bands. Overall, curved stations trended louder than straight stations, although the difference in broadband L eq did not reach statistical significance (curve, 83.4 dBA; straight, 82.6 dBA; P = .054). Noise levels were significantly louder at the inbound end of the platform during train entry (inbound, 89.7 dBA; mid, 85.5 dBA; outbound, 78.7 dBA; P < .001) and at the outbound end during train exit (inbound, 79.7 dBA; mid, 85.3 dBA; outbound, 89.1 dBA; P < .001). Narrow band analysis showed that curved stations were significantly louder than straight stations at 100 Hz and high frequencies from 8 to 20 kHz. Peak impact levels ranged from 104 to 121 dBA. Curved stations have a different noise profile compared to straight stations and are significantly louder than straight stations at high frequencies. Designing stations with straight tracks within the platform can help reduce commuter noise exposure. NA Laryngoscope, 127:1169-1174, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Violence in Advertisements in New York City Subway Stations: A Pilot Study

PubMed Central

Basch, Corey H.; Fullwood, M. D.; LeBlanc, Michael

2017-01-01

Violence has become a public health concern in the United States. Violent visually stimulating content encompasses various techniques such as fear, humor, shock, or violence, to stimulate a response or appeal toward awareness of human emotion. Exposing impressionable youth to violent advertisements can be particularly problematic. This is especially true in places like New York City where violent crime is a prevalent problem. With annual ridership reaching over 1.7 billion in 2014, the New York City subway system is abundant with advertisements. The purpose of this pilot study was to determine the frequency and type of violent advertising on the Lexington Avenue/East Side Line in New York City, running through the Bronx and Manhattan to represent the lower and higher median income earning boroughs. There were no statistically different findings in median household income at site of station by number of ads or source of violent. Destruction was the most common form of violence (n = 32, 42.7 %) followed by intent to strike (n = 18, 24 %), showing a weapon (n = 15, 20 %) and horror (n = 10, 13.3 %). Most ads (n = 46, 61.3 %) were found in stations heading uptown toward and through the Bronx, the borough where median household income is lowest, whereas 29 (38.7 %) were found in stations heading downtown. Future studies could focus on additional boroughs and subways lines, and could be collected at multiple points in time to determine of how prevalent violent advertising is throughout New York City and at different time frames. PMID:26518776

Supplementary subsurface investigation section G-4aL, Addison route

DOT National Transportation Integrated Search

2000-09-22

Results are summarized herein of five supplementary borings to investigate subsurface conditions along the subway alignment at the planned location of the Addison Route crossing of the Capital Beltway. The report contains geological sections which su...

Real-time subway information for improving transit ridership.

DOT National Transportation Integrated Search

2016-08-01

In recent years, the standardization of transit schedule information has yielded a dramatic increase in the accessibility of computerized transit schedules and given rise to real-time service schedules. Two such real-time service schedules are the Ge...

Study of Subway Station Design and Construction

DOT National Transportation Integrated Search

1977-03-01

Due to the high cost of urban underground transit construction in recent years, construction practices used in other countries were reviewed to determine if construction methods which are commonly accepted there might be adapted to U.S. practice. Des...

Infrastructure-Free Mapping and Localization for Tunnel-Based Rail Applications Using 2D Lidar

NASA Astrophysics Data System (ADS)

Daoust, Tyler

This thesis presents an infrastructure-free mapping and localization framework for rail vehicles using only a lidar sensor. The method was designed to handle modern underground tunnels: narrow, parallel, and relatively smooth concrete walls. A sliding-window algorithm was developed to estimate the train's motion, using a Renyi's Quadratic Entropy (RQE)-based point-cloud alignment system. The method was tested with datasets gathered on a subway train travelling at high speeds, with 75 km of data across 14 runs, simulating 500 km of localization. The system was capable of mapping with an average error of less than 0.6 % by distance. It was capable of continuously localizing, relative to the map, to within 10 cm in stations and at crossovers, and 2.3 m in pathological sections of tunnel. This work has the potential to improve train localization in a tunnel, which can be used to increase capacity and for automation purposes.

The benefit of 3D laser scanning technology in the generation and calibration of FEM models for health assessment of concrete structures.

PubMed

Yang, Hao; Xu, Xiangyang; Neumann, Ingo

2014-11-19

Terrestrial laser scanning technology (TLS) is a new technique for quickly getting three-dimensional information. In this paper we research the health assessment of concrete structures with a Finite Element Method (FEM) model based on TLS. The goal focuses on the benefits of 3D TLS in the generation and calibration of FEM models, in order to build a convenient, efficient and intelligent model which can be widely used for the detection and assessment of bridges, buildings, subways and other objects. After comparing the finite element simulation with surface-based measurement data from TLS, the FEM model is determined to be acceptable with an error of less than 5%. The benefit of TLS lies mainly in the possibility of a surface-based validation of results predicted by the FEM model.

Dynamic Performance of Subway Vehicle with Linear Induction Motor System

NASA Astrophysics Data System (ADS)

Wu, Pingbo; Luo, Ren; Hu, Yan; Zeng, Jing

The light rail vehicle with Linear Induction Motor (LIM) bogie, which is a new type of urban rail traffic tool, has the advantages of low costs, wide applicability, low noise, simple maintenance and better dynamic behavior. This kind of vehicle, supported and guided by the wheel and rail, is not driven by the wheel/rail adhesion force, but driven by the electromagnetic force between LIM and reaction plate. In this paper, three different types of suspensions and their characteristic are discussed with considering the interactions both between wheel and rail and between LIM and reaction plate. A nonlinear mathematical model of the vehicle with LIM bogie is set up by using the software SIMPACK, and the electromechanical model is also set up on Simulink roof. Then the running behavior of the LIM vehicle is simulated, and the influence of suspension on the vehicle dynamic performance is investigated.

Preparedness and catastrophic event management for the Washington, D.C. metropolitan area.

DOT National Transportation Integrated Search

2010-12-01

The devastating effects of terrorism are distinctly clear and realistic to our generation with the haunting September 11 attacks, the 2005 subway bombings in London, the 2009 attempted Christmas attack, and constant turmoil overseas. Therefore, it is...

Noise test-corrugated rails Washington Metropolitan Area Transit Authority : letter report

DOT National Transportation Integrated Search

1981-12-31

Noise and ground-borne vibration level measurements were made on a section of the Huntington subway route of the Washington Area Metropolitan Transit Authority (WMATA). Measurements were made before, in between, and after a WMATA sponsored rail grind...

Technotown: A LEGO Experience. [and] Technotown: A School-Wide Design Technology Project.

ERIC Educational Resources Information Center

Belch, Harry; Knobloch, Stephan F.

1994-01-01

Describes how 900 elementary students planned, designed, and constructed Technotown out of 1 million LEGO pieces. Presents a learning activity (objectives, materials, challenge, evaluation, and closing thoughts) on the building of a subway system for Technotown. (SK)

Recent Developments in Ground-Borne Noise and Vibration Control

NASA Astrophysics Data System (ADS)

Nelson, J. T.

1996-05-01

Vibration control provisions available to the transit designer include (among others) precision straightened rail, ballast mats, floating slabs and very soft direct fixation fasteners, in addition to rail grinding, wheel truing, and continuous welded rail. Recently, the Los Angeles Metro has developed specifications for a soft resilient direct fixation fastener to fit the same base dimensions as the standard direct fixation fastener. In San Francisco, low resonance frequency (8 Hz) floating slabs have been constructed to mitigate predicted ground vibration impacts at nearby residential structures. In Atlanta, low resonance frequency loading slabs have been constructed to maintain a low vibration environment in a medical building planned to be built over the subway structure. In Portland and Pasadena, ballast mats have been recommended to control light rail transit ground vibration impacts on housing located at typically 35 feet from the alignment. Each of these provisions are briefly described in view of recent applications at U.S. transit systems.

Limited Investigation into Regenerative Braking and Energy Storage for Mass Transit Systems

DOT National Transportation Integrated Search

1978-03-01

This study examines the technical and economic aspects of a regenerative braking/flywheel energy storage subway system. In order to define the analytical models accurately, it was necessary to gather data on the trains, rail network, schedules, and a...

3. GENERAL VIEW AT 148TH ST. WILLIS AVENUE, 149TH ...

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

3. GENERAL VIEW AT 148TH ST. - WILLIS AVENUE, 149TH ST. STATION. TRANSFER STRUCTURE TO SUBWAY IS LIGHT COLOR BUILDING IN FOREGROUND. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY

The politics of large infrastructure investment decision-making : the case of the second avenue subway case study.

DOT National Transportation Integrated Search

2013-11-01

Over the past few decades, urbanization and economic growth have intensified the need for more efficient urban and : regional transportation, including the expansion and reorganization of existing transportation networks. Given such : huge investment...

Noise Assessment of the Southeastern Pennsylvania Transportation Authority Heavy Rail Transit System

DOT National Transportation Integrated Search

1978-10-01

The report describes the noise climate on and near the Southeastern Pennsylvania Transportation Authority, (SEPTA), Broad Street Subway and Market-Frankford Elevated Line. The two SEPTA urban rail transit lines have approximately 22.6 miles of two-wa...

Networks--New York Subways, A Piece of String, and African Traditions.

ERIC Educational Resources Information Center

Zaslavsky, Claudia

1981-01-01

Introducing network theory to schoolchildren is promoted as a way of encouraging students to deal with new situations, be unafraid of challenges, and learn to think. Several applications, methods of analysis, and suggestions for further activities are provided. (MP)

Suicide Epidemics and Newspaper Reporting.

ERIC Educational Resources Information Center

Littmann, Sebastian K.

1985-01-01

Examines the relationship between suicide-related newspaper reports and a subway-suicide epidemic. More reports were published during the epidemic, without statistically significant differences between epidemic and nonepidemic years. There did not appear to be an excess of reports antecedent to the suicide. (Author/BL)

Train-induced field vibration measurements of ground and over-track buildings.

PubMed

Zou, Chao; Wang, Yimin; Moore, James A; Sanayei, Masoud

2017-01-01

Transit-oriented development, such as metro depot and over-track building complexes, has expanded rapidly over the last 5years in China. Over-track building construction has the advantage of comprehensive utilization of land resources, ease of commuting to work, and provide funds for subway construction. But the high frequency of subway operations into and out of the depots can generate excessive vibrations that transmit into the over track buildings, radiate noise within the buildings, hamper the operation of vibration sensitive equipment, and adversely affect the living quality of the building occupants. Field measurements of vibration during subway operations were conducted at Shenzhen, China, a city of 10.62 million people in southern China. Considering the metro depot train testing line and throat area train lines were the main vibration sources, vibration data were captured in five measurement setups. The train-induced vibrations were obtained and compared with limitation of FTA criteria. The structure-radiated noise was calculated using measured vibration levels. The vertical vibration energy directly passed through the columns on both sides of track into the platform, amplifying vibration on the platform by up to 6dB greater than ground levels at testing line area. Vibration amplification around the natural frequency in the vertical direction of over-track building made the peak values of indoor floor vibration about 16dB greater than outdoor platform vibration. We recommend to carefully examining design of new over-track buildings within 40m on the platform over the throat area to avoid excessive vertical vibrations and noise. For both buildings, the measured vertical vibrations were less than the FTA limit. However, it is demonstrated that the traffic-induced high-frequency noise has the potential to annoy occupants on the upper floors. Copyright © 2016 Elsevier B.V. All rights reserved.

Prediction of vibrations induced by underground railway traffic in Beijing

NASA Astrophysics Data System (ADS)

Gupta, S.; Liu, W. F.; Degrande, G.; Lombaert, G.; Liu, W. N.

2008-02-01

This paper examines the problem of subway induced vibrations on line 4 of Beijing metro, which is currently under construction and is planned to pass in close proximity of the Physics Laboratory of Beijing University. The laboratory has a lot of equipment that is very sensitive to traffic induced vibrations and future operation of metro line 4 is a matter of concern. Hence, it is important to study the influence of subway induced vibrations inside the laboratory and to propose a viable solution to mitigate the vibrations. In this paper, the tunnel north of Chengfulu station is modelled using a coupled periodic FE-BE model and the free-field response due to moving trains is predicted. In addition, vibration measurements have been performed on the site of the Physics Laboratory to estimate the existing vibration levels due to road traffic. The predicted and measured vibrations are superimposed to assess the vibrations due to the combined effect of road and railway traffic in the vicinity of the Physics Laboratory. Apart from the numerical investigations, vibration measurements have also been performed on a similar site at line 1 of Beijing metro to substantiate the estimated results on metro line 4. Finally, it is studied how the vibrations can be controlled using a floating slab track, which is widely used as an effective measure of vibration isolation in tunnels. The efficiency of a 7.9 Hz floating slab track as a vibration countermeasure is assessed in this paper. This study demonstrates the applicability of the numerical model for the relevant assessment of subway induced vibrations and its use to study the performance of different track structures in the tunnel.

Urinary 8-hydroxy-deoxyguanosine as a biomarker of oxidative DNA damage in employees of subway system.

PubMed

Mehrdad, Ramin; Aghdaei, Sara; Pouryaghoub, Gholamreza

2015-01-01

Exposure to air pollutants, steel dust or other occupational and environmental hazards as oxidative stress have adverse effects on subway workers' health. Oxidative stress generates an excessive amount of reactive oxygen species (ROS) and Oxygen Free Radicals during their work time in the tunnels. Once DNA is repaired, Urinary 8-hydroxy-deoxyguanosine (8-OHdG) is excreted in the urine. Therefore, urinary level of 8-OHdG can reflect the extent of oxidative DNA damage. The aim of this study was to document the oxidative stress caused by exposure to these hazards by measuring 8-OHdG in workers urine. We collected urine samples of 81 male subway workers after their working shift. The concentration of urinary 8-OHdG was measured by ELISA method. We used linear regression analysis to compare the level of urinary 8-OHdG as a biomarker of oxidative stress between workers in tunnels and other staff. The mean concentration of urinary 8-OHdG for workers in the tunnel was 58.05 (SD=28.83) ng/mg creatinine and for another staff was 54.16 (SD =26.98) ng/mg creatinine.  After adjustment for age, smoking, driving and a second job in a linear regression model, the concentration of 8-OHdG for the exposed group was significantly higher than unexposed group (P=0.038). These findings confirm that the concentration of urinary 8-OHdG for workers who work in tunnels was significantly higher than the other staff. Additional investigations should be performed to understand that which ones of occupational exposures are more important to cause oxidative stress.

Survival After Ventricular Fibrillation Cardiac Arrest in the Sao Paulo Metropolitan Subway System: First Successful Targeted Automated External Defibrillator (AED) Program in Latin America.

PubMed

Gianotto-Oliveira, Renan; Gonzalez, Maria Margarita; Vianna, Caio Brito; Monteiro Alves, Maurício; Timerman, Sergio; Kalil Filho, Roberto; Kern, Karl B

2015-10-09

Targeted automated external defibrillator (AED) programs have improved survival rates among patients who have an out-of-hospital cardiac arrest (OHCA) in US airports, as well as European and Japanese railways. The Sao Paulo (Brazil) Metro subway carries 4.5 million people per day. A targeted AED program was begun in the Sao Paulo Metro with the objective to improve survival from cardiac arrest. A prospective, longitudinal, observational study of all cardiac arrests in the Sao Paulo Metro was performed from September 2006 through November 2012. This study focused on cardiac arrest by ventricular arrhythmias, and the primary endpoint was survival to hospital discharge with minimal neurological impairment. A total of 62 patients had an initial cardiac rhythm of ventricular fibrillation. Because no data on cardiac arrest treatment or outcomes existed before beginning this project, the first 16 months of the implementation was used as the initial experience and compared with the subsequent 5 years of full operation. Return of spontaneous circulation was not different between the initial 16 months and the subsequent 5 years (6 of 8 [75%] vs. 39 of 54 [72%]; P=0.88). However, survival to discharge was significantly different once the full program was instituted (0 of 8 vs. 23 of 54 [43%]; P=0.001). Implementation of a targeted AED program in the Sao Paulo Metro subway system saved lives. A short interval between arrest and defibrillation was key for good long-term, neurologically intact survival. These results support strategic expansion of targeted AED programs in other large Latin American cities. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Should Helicopters Transport Patients Who Become Sick After a Chemical, Biological, Radiological, Nuclear, and Explosive Attack?

PubMed

Yanagawa, Youichi; Ishikawa, Kouhei; Takeuchi, Ikuto; Nagasawa, Hiroki; Jitsuiki, Kei; Ohsaka, Hiromichi; Omori, Kazuhiko

The local fire department executed a training simulation for chemical and explosive incidents at a large sports facility. In this training simulation, a physician-staffed helicopter arrived at the request of the fire department and landed just outside the cold zone in the parking area. The doctor and nurse of the helicopter were escorted to a red area in the cold zone, which was selected based on the results of postdecontamination triage. After the patients had been treated, they were air medically evacuated to the base hospital. In the Tokyo subway sarin attack in 1995, St Luke's International Hospital admitted over 600 victims. During this incident, 23.2% of medical staff suffered secondary injury from sarin exposure. If air medial crews respond with subsequent postexposure effects during flight, an affected pilot could lose control of the helicopter, resulting in a fatal crash. Based on potential safety concerns for air medical and ground personnel, our recommendation would be that air medical helicopters not be dispatched to sites of chemical, biological, radiological, nuclear, and explosive incidents. Copyright © 2018 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.

Preventing Terrorist Bombings on United States Subway Systems

DTIC Science & Technology

2006-09-01

underlying altruistic motivations. Over 100 years ago, Emile Durkheim defined the phenomenon of suicide as comprising four categories: altruistic, egoistic...family and friends’ lot in life in an altruistic suicide as previously described by Durkheim . Suicide terrorism grows out of a necessity based on

Global Positioning System Disaster Notification Messaging Service

DTIC Science & Technology

2013-09-01

under AT&T service. Differing combinations of phone operating system types and versions (Android, iOS, Windows 8, Blackberry OS, et al.) service...streets, tunnels and subways. Substantial damage was incurred along the Atlantic coasts of both states with sustained power outages. As the storm’s

Evaluating the Impacts of Real-Time Information on Subway Ridership in New York City

DOT National Transportation Integrated Search

2018-05-21

It is now common for transit operators to provide real-time information (RTI) to passengers about the location or predicted arrival times of transit vehicles. The Metropolitan Transportation Authority (MTA) in New York City has recently made RTI avai...

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...

26 CFR 1.132-2 - No-additional-cost services.

Code of Federal Regulations, 2011 CFR

2011-04-01

... capacity services such as hotel accommodations; transportation by aircraft, train, bus, subway, or cruise... transportation). Similarly, maid service provided to hotel employees renting hotel rooms on a space-available basis is merely incidental to the primary service being provided (i.e., hotel accommodations). (6...

Broadband hybrid electromagnetic and piezoelectric energy harvesting from ambient vibrations and pneumatic vortices induced by running subway trains.

DOT National Transportation Integrated Search

2017-05-01

The airfoil-based electromagnetic energy harvester containing parallel array motion between moving coil and : trajectory matching multi-pole magnets was investigated. The magnets were aligned in an alternatively : magnetized formation of 6 magnets to...

26 CFR 1.132-2 - No-additional-cost services.

Code of Federal Regulations, 2010 CFR

2010-04-01

... capacity services such as hotel accommodations; transportation by aircraft, train, bus, subway, or cruise... transportation). Similarly, maid service provided to hotel employees renting hotel rooms on a space-available basis is merely incidental to the primary service being provided (i.e., hotel accommodations). (6...

Vibration Prediction Model for Floating-Slab Rail Transit Track

DOT National Transportation Integrated Search

1975-08-01

This report presents the theoretical development of a model to predict the vibration reduction by floating-slab tracks in subway tunnels. Data from a field study in New York City are also presented. The report is one of three reports dealing with noi...

The Comprehensive Benefit Evaluation of Take Shared Bicycles as Connecting to Public Transit

NASA Astrophysics Data System (ADS)

Zhang, J. Y.; Sun, H.; Li, P. F.; Li, C. C.

2017-10-01

Shared bicycles as an important way of connecting public transport, have few literature to evaluate its effectiveness.This paper taking Beijing city as an example, make anevaluationfor the six types of travel combinations which are commonly used by the citizens. The author selects four quantitative indicators: fuel consumption, economic cost, total time spent, and CO2 emission. And two qualitative indicators: degree of comfort and convenience. The relative efficiency of quantitative indicators is obtained by data envelopment analysis (DEA) and fuzzification and then take fuzzy synthetic evaluation with qualitative indicators.It was found that the choice of shared bicycles +subway+ shared bicycles and shared bicycles has good comprehensive benefits in medium distance travel. The findings also suggest that shared bicycles +subway+ shared bicycles is the best choice in the utilitarian trips. The conclusions not only provide suggestions for the travellers to select travel modes, but also can adjust the relevant factors to increase the proportion of green travel.

Cascading failures in interconnected networks with dynamical redistribution of loads

NASA Astrophysics Data System (ADS)

Zhao, Zhuang; Zhang, Peng; Yang, Hujiang

2015-09-01

Cascading failures of loads in isolated networks and coupled networks have been studied in the past few years. In most of the corresponding results, the topologies of the networks are destroyed. Here, we present an interconnected network model considering cascading failures based on the dynamic redistribution of flow in the networks. Compared with the results of single scale-free networks, we find that interconnected scale-free networks have higher vulnerability. Additionally, the network heterogeneity plays an important role in the robustness of interconnected networks under intentional attacks. Considering the effects of various coupling preferences, the results show that there are almost no differences. Finally, the application of our model to the Beijing interconnected traffic network, which consists of a subway network and a bus network, shows that the subway network suffers more damage under the attack. Moreover, the interconnected traffic network may be more exposed to damage after initial attacks on the bus network. These discussions are important for the design and optimization of interconnected networks.

Evaluation of Commercially-Available Equipment for the ...

EPA Pesticide Factsheets

Report The Underground Transport Restoration (UTR) project is an inter-agency effort. This effort aims to improve the capability for transit systems to quickly and efficiently recover from a biological contamination incident by refining existing methods, tools and protocols for characterization, clean-up, and clearance of contamination in physical structures (i.e., tunnels, stations) and rolling stock (i.e., subway trains). The aim was to evaluate existing sampling, characterization, and decontamination technologies through experimentation, table-top exercises and operational demonstrations to develop guidance and decision frameworks and support tools through interactions of local, state and federal partners. In this investigation, a survey of commercially-available or fielded equipment was conducted and resulted in three pieces of identified equipment that could be used or rapidly modified for use in dispensing liquid chemicals to decontaminate surfaces following a biological contamination incident. documenting lab-scale testing, field-scale testing, and an equipment demonstration of commercial equipment used to decontaminate subway infrastructure following a biological incident.

NeuroLines: A Subway Map Metaphor for Visualizing Nanoscale Neuronal Connectivity.

PubMed

Al-Awami, Ali K; Beyer, Johanna; Strobelt, Hendrik; Kasthuri, Narayanan; Lichtman, Jeff W; Pfister, Hanspeter; Hadwiger, Markus

2014-12-01

We present NeuroLines, a novel visualization technique designed for scalable detailed analysis of neuronal connectivity at the nanoscale level. The topology of 3D brain tissue data is abstracted into a multi-scale, relative distance-preserving subway map visualization that allows domain scientists to conduct an interactive analysis of neurons and their connectivity. Nanoscale connectomics aims at reverse-engineering the wiring of the brain. Reconstructing and analyzing the detailed connectivity of neurons and neurites (axons, dendrites) will be crucial for understanding the brain and its development and diseases. However, the enormous scale and complexity of nanoscale neuronal connectivity pose big challenges to existing visualization techniques in terms of scalability. NeuroLines offers a scalable visualization framework that can interactively render thousands of neurites, and that supports the detailed analysis of neuronal structures and their connectivity. We describe and analyze the design of NeuroLines based on two real-world use-cases of our collaborators in developmental neuroscience, and investigate its scalability to large-scale neuronal connectivity data.

Agricultural Bioterrorism What Challenges and Actions Remain

DTIC Science & Technology

2006-03-10

African milk bush.29 In 1966, Bacillus subtilis was released in the New York City subway system to test the vulnerability of biowarfare.30 In 1984...These diseases include: Foot and Mouth Disease (FMD), Rift Valley Fever ( RVF ), Nipah Virus, Avian Influenza, Exotic Newcastle Disease, Classical Swine

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...

Noise Assessment of the Bay Area Rapid Transit System

DOT National Transportation Integrated Search

1978-10-01

The report describes the noise on and near the San Francisco Bay Area Rapid Transit System (BART). BART has approximately 75 miles of two-way revenue track (of which 19.7 miles are in subway) and 34 stations. Noise data is given for specific measurem...

Fighting Downtown: A Training Necessity for the Heavy Brigade

DTIC Science & Technology

2001-02-01

Concept Technology Demonstration, and the Army Transformation Urban Franchise exploration of future operations.”57 CAMTF has identified three...fighting in a downtown area with tall buildings and underground sewers and or subways , but it must also apply to the outlying urban sprawl that is now

Three-dimensional numerical modeling of land subsidence in Shanghai, China

NASA Astrophysics Data System (ADS)

Ye, Shujun; Luo, Yue; Wu, Jichun; Yan, Xuexin; Wang, Hanmei; Jiao, Xun; Teatini, Pietro

2016-05-01

Shanghai, in China, has experienced two periods of rapid land subsidence mainly caused by groundwater exploitation related to economic and population growth. The first period occurred during 1956-1965 and was characterized by an average land subsidence rate of 83 mm/yr, and the second period occurred during 1990-1998 with an average subsidence rate of 16 mm/yr. Owing to the establishment of monitoring networks for groundwater levels and land subsidence, a valuable dataset has been collected since the 1960s and used to develop regional land subsidence models applied to manage groundwater resources and mitigate land subsidence. The previous geomechanical modeling approaches to simulate land subsidence were based on one-dimensional (1D) vertical stress and deformation. In this study, a numerical model of land subsidence is developed to simulate explicitly coupled three-dimensional (3D) groundwater flow and 3D aquifer-system displacements in downtown Shanghai from 30 December 1979 to 30 December 1995. The model is calibrated using piezometric, geodetic-leveling, and borehole extensometer measurements made during the 16-year simulation period. The 3D model satisfactorily reproduces the measured piezometric and deformation observations. For the first time, the capability exists to provide some preliminary estimations on the horizontal displacement field associated with the well-known land subsidence in Shanghai and for which no measurements are available. The simulated horizontal displacements peak at 11 mm, i.e. less than 10 % of the simulated maximum land subsidence, and seems too small to seriously damage infrastructure such as the subways (metro lines) in the center area of Shanghai.

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...

49 CFR 1580.3 - Terms used in this part.

Code of Federal Regulations, 2013 CFR

2013-10-01

... uses diesel or electric powered locomotives and railroad passenger cars to serve an urban area, its... electric railcars, typically drawing power from a third rail, operating in separate rights-of-way in multiple cars; also referred to as subways, metros, or regional rail. High Threat Urban Area (HTUA) means...

49 CFR 1580.3 - Terms used in this part.

Code of Federal Regulations, 2014 CFR

2014-10-01

... uses diesel or electric powered locomotives and railroad passenger cars to serve an urban area, its... electric railcars, typically drawing power from a third rail, operating in separate rights-of-way in multiple cars; also referred to as subways, metros, or regional rail. High Threat Urban Area (HTUA) means...

49 CFR 1580.3 - Terms used in this part.

Code of Federal Regulations, 2012 CFR

2012-10-01

... uses diesel or electric powered locomotives and railroad passenger cars to serve an urban area, its... electric railcars, typically drawing power from a third rail, operating in separate rights-of-way in multiple cars; also referred to as subways, metros, or regional rail. High Threat Urban Area (HTUA) means...

Emergency Medical Services (EMS) Public Information, Education and Relations (PIER): National Standard Curriculum (Administrator's Guide)

DOT National Transportation Integrated Search

1997-01-01

Imagine a transportation network linked by information and technology that makes travel quicker, safer and easier. Imagine being able to plot your route before you leave your home or office and know exactly how long it will take you - by car, subway ...

Simplicity and Innovation Make This "Green" Brazilian City Work.

ERIC Educational Resources Information Center

Goodstein, Carol

1993-01-01

Describes how a Brazilian city, Curitiba, is successfully curbing environmental degradation through recycling efforts, transportation, housing, and land use changes. These projects include tree planting, decreased automobile use, a simple technology that enables buses to run as quickly and efficiently as subways, and increasing city open space…

Using Visual Information to Determine the Subjective Valuation of Public Space for Transportation : Application to Subway Crowding Costs in NYC

DOT National Transportation Integrated Search

2017-11-30

The objective of this project is to explore the role of visual information in determining the users subjective valuation of multidimensional trip attributes that are relevant in decision-making, but are neglected in standard travel demand models. ...

Noise Assessment of the Chicago Transit Authority Rail Rapid Transit System

DOT National Transportation Integrated Search

1979-01-01

The report describes the noise on and near the Chicago Transit Authority (CTA) urban rail transit lines. The CTA urban rail lines consist of approximately 86 miles of two-way revenue track (of which 9.6 miles are in subway) and 155 stations. Noise da...

49 CFR 1580.3 - Terms used in this part.

Code of Federal Regulations, 2011 CFR

2011-10-01

... uses diesel or electric powered locomotives and railroad passenger cars to serve an urban area, its... electric railcars, typically drawing power from a third rail, operating in separate rights-of-way in multiple cars; also referred to as subways, metros, or regional rail. High Threat Urban Area (HTUA) means...

49 CFR 1580.3 - Terms used in this part.

Code of Federal Regulations, 2010 CFR

2010-10-01

... uses diesel or electric powered locomotives and railroad passenger cars to serve an urban area, its... electric railcars, typically drawing power from a third rail, operating in separate rights-of-way in multiple cars; also referred to as subways, metros, or regional rail. High Threat Urban Area (HTUA) means...

Survey of Sliding Contact/Solid Rail Power Collection Systems for Application to the Tracked Air Cushion Vehicle

DOT National Transportation Integrated Search

1971-01-01

The objective of a power collection system is to deliver uninterrupted power from the wayside to a vehicle. In order to apply the third rail concept, used for subway power collection, to the tracked air cushion vehicle, considerable improvement must ...

West Europe Report, Science and Technology, No. 152.

DTIC Science & Technology

1983-08-12

Technology (created 3 years ago by the CGE group), who recently won a contract to supply an automated ticketing system for Buffalo’s subway . But...plastic sandwich construction. The strut junction fairing between the struts and the lower side of the wing, the upper side of the fuselage and the

Protection of Department of Defense Facilities from Airborne CBR Threats: An Annotated Bibliography

DTIC Science & Technology

2004-09-01

resistance. The use and control of smoke or isolation dampers plays a key role, along with the definition of smoke control zones and sandwich ...educational facilities; and other areas of public assembly such as stadiums, coliseums, and vehicle tunnels and subways . This scope also pertains to

The Multi-Agent Tactical Sentry: Designing and Delivering Robots to the CF

DTIC Science & Technology

2008-08-01

believed that there is no substitute for having the man in the loop during military operations. After the World Trade Center and Tokyo subway attacks...and vibration isolation for the more sensitive components. Additional space was left to account for possible future changes to the primary sensors

Citystore

Science.gov Websites

View Cart FAQs Contact Newsletter Register to Vote Search CityStore Products Gifts Books Municipal From The Archives Made in NY Color NYC Books Make Great Gifts for Kids! NYC Subway Married in New York updates on Facebook and Twitter! flowers citystore citystore Visit Us CityStore has two stores. Our David

Mourning into Dancing.

ERIC Educational Resources Information Center

Savage, Mary C.

1990-01-01

Asserts that unacknowledged grief has created a pernicious, low-grade depression in many North Americans, and that mourning has become a metaphor for the educational work that needs to be done. States that race relations, educational hierarchies, neighborhoods, and subway rides are all made by humans, and that mourning allows a more hopeful…

The Collins Center Update. Volume 9, Issue 3, April-June 2007

DTIC Science & Technology

2007-06-01

already persuaded populace as a means of lightweight engagement. An example includes the popular uprising in Spain after the subway bombings, where...of the nation-state may be usurped by the power of the corporation, the power of the loosely organized franchise and even the power of the

An Invisible Scalpel: Low-Visibility Operations in the War on Terror

DTIC Science & Technology

2006-06-16

past. The current al Qaeda therefore exists more as an ideology that has become a vast enterprise--an international franchise with like-minded local......Australian embassy bombing in Jakarta in 2004, and the London subway bombings in 2005. Although some al Qaeda associates have formations of uniformed

Shock wave attenuation by water droplets

NASA Astrophysics Data System (ADS)

Eliasson, Veronica; Wan, Qian; Deiterding, Ralf

2017-11-01

The ongoing research on shock wave attenuation is fueled by the desire to predict and avoid damage caused by shock and blast waves. For example, during an explosion in an underground mine or subway tunnel, the shock front is forced to propagate in the direction of the channel. In this work, numerical simulations using water droplets in a 2D channel are conducted to study shock wave attenuation. Four different droplet configurations (1x1, 2x2, 3x3, and 4x4) are considered, where the total volume of water is kept constant throughout all the cases. Meanwhile, the incident shock Mach number was varied from 1.1 to 1.4 with increments of 0.1. The physical motion of the water droplets, such as the center-of-mass drift and velocity, and the energy exchange between air and water are quantitatively studied. Results for center-of-mass velocity, maximum peak pressure and impulse will be presented for all different cases that were studied. NSF CBET-1437412.

40 CFR 52.1163 - Additional control measures for East Boston.

Code of Federal Regulations, 2011 CFR

2011-07-01

...”) shall each submit to the Regional Administrator a study or studies of various alternative strategies to... transit service between the Blue Line subway stop and airline terminals at Logan Airport; and (8) Any... information in tickets or folders mailed by airlines using Logan Airport) to publicize the advantages in costs...

40 CFR 52.1163 - Additional control measures for East Boston.

Code of Federal Regulations, 2010 CFR

2010-07-01

...”) shall each submit to the Regional Administrator a study or studies of various alternative strategies to... transit service between the Blue Line subway stop and airline terminals at Logan Airport; and (8) Any... information in tickets or folders mailed by airlines using Logan Airport) to publicize the advantages in costs...

40 CFR 52.1163 - Additional control measures for East Boston.

Code of Federal Regulations, 2014 CFR

2014-07-01

...”) shall each submit to the Regional Administrator a study or studies of various alternative strategies to... transit service between the Blue Line subway stop and airline terminals at Logan Airport; and (8) Any... information in tickets or folders mailed by airlines using Logan Airport) to publicize the advantages in costs...

40 CFR 52.1163 - Additional control measures for East Boston.

Code of Federal Regulations, 2012 CFR

2012-07-01

...”) shall each submit to the Regional Administrator a study or studies of various alternative strategies to... transit service between the Blue Line subway stop and airline terminals at Logan Airport; and (8) Any... information in tickets or folders mailed by airlines using Logan Airport) to publicize the advantages in costs...

40 CFR 52.1163 - Additional control measures for East Boston.

Code of Federal Regulations, 2013 CFR

2013-07-01

...”) shall each submit to the Regional Administrator a study or studies of various alternative strategies to... transit service between the Blue Line subway stop and airline terminals at Logan Airport; and (8) Any... information in tickets or folders mailed by airlines using Logan Airport) to publicize the advantages in costs...

Inertial Navigation: A Bridge between Kinematics and Calculus

ERIC Educational Resources Information Center

Sadler, Philip M.; Garfield, Eliza N.; Tremblay, Alex; Sadler, Daniel J.

2012-01-01

Those who come to Cambridge soon learn that the fastest route between Harvard and MIT is by the subway. For many students, this short ride is a quick and easy way to link physics and calculus. A simple, homemade accelerometer provides all the instrumentation necessary to produce accurate graphs of acceleration, velocity, and displacement position…

A CompStat Counterterrorism Strategy to Protect Train and Subway Systems

DTIC Science & Technology

2008-03-01

other aspect of this collection of information, including suggestions for reducing this burden, to Washington headquarters Services , Directorate for...Explosives on the London Underground .........................................54 VI. RECOVERY ...evacuation plan in an effort to aid in the recovery from an attack. This is essential in preventing the terrorists from accomplishing their goals of

Environmental Assessment Temporary Use of a Training Airport

DTIC Science & Technology

2003-01-01

NOISE LEVEL COMMON INDOOR NOISE LEVELS (dBA) NOISE LEVELS -- 110 Rock Band - - 100 Gas Lawn Mower at 3 ft. Inside Subway Train (New York) - - 90...Diesel Truck at 50 ft. Food Blender at 3 ft. Noise Urban Daytime - -80 Garbage Disposal at 3 ft. Shouting at 3 ft. Gas Lawn Mower at 100 ft

Dirty Bombs: The Technical Aspects of Radiological Dispersion Devices

DTIC Science & Technology

2004-06-01

people such as a business district, subway station, or entertainment district. By striking one of these targets not only would many people be directly...the resulting 35 appearance. One six-year-old girl “rubbed the powder on her body so that she glowed and sparkled” and later ate a sandwich with

Proceedings of the Antenna Applications Symposium Held on 25-27 September 1991. Volume 2

DTIC Science & Technology

1992-02-01

structure sandwiched by two thin parabolic surfaces. The antenna support deck is also a honeycomb structure. To reduce on-orbit thermally induced...various sights are the Hermitage art museum, the KIROV ballet at $45 a seat (INTOURIST controlled), beautiful subway stations at 5 Kopeks a ride (less than

Comfort Foods and Mood

DTIC Science & Technology

2008-07-01

others much larger - have developed into mini-American towns.On some bases, troops fresh off of a patrol can stroll in for a sandwich at a makeshift... Subway , grab a pie at Pizza Hut or get a Whopper from Burger King. QuickTime™ and a decompressor are needed to see this picture. Even in the chow

Commercial applications

NASA Technical Reports Server (NTRS)

Togai, Masaki

1990-01-01

Viewgraphs on commercial applications of fuzzy logic in Japan are presented. Topics covered include: suitable application area of fuzzy theory; characteristics of fuzzy control; fuzzy closed-loop controller; Mitsubishi heavy air conditioner; predictive fuzzy control; the Sendai subway system; automatic transmission; fuzzy logic-based command system for antilock braking system; fuzzy feed-forward controller; and fuzzy auto-tuning system.

Teaching Machines to Think Fuzzy

ERIC Educational Resources Information Center

Technology Teacher, 2004

2004-01-01

Fuzzy logic programs for computers make them more human. Computers can then think through messy situations and make smart decisions. It makes computers able to control things the way people do. Fuzzy logic has been used to control subway trains, elevators, washing machines, microwave ovens, and cars. Pretty much all the human has to do is push one…

WMD Proliferation, Globalization, and International Security: Whither the Nexus and National Security?

DTIC Science & Technology

2006-07-01

group Aum Shinrikyo on the Tokyo subway system, which resulted in 10 deaths, is regarded by many as the dawn of the era of modern WMD terrorism...organizations have become truly global in character. Al Qaeda, for example, is franchising operations around the world either directly or indirectly

On the influence of a raffle upon responses to an urban transportation survey in New York City.

PubMed

Morabia, Alfredo; Zheng, Yan

2009-01-01

Determine whether raffling off prizes to increase participation in surveys triggers multiple responses from the same participants. All staff, instructors, and students of Queens College, New York, were invited to a 5 minute online survey about commuting in winter 2007. Entry in the raffle to win one of two iPODs was not conditional upon survey completion. Participation was 18.7 %, and 3913 eligible responses. Of the 183 (4.7 %) participants with two answers, responses were consistent, with weighted kappas ranging between 0.48 and 1.00, and Pearson r's between 0.81 and 1.0. Kappa's were lower for opinion than for factual questions. The duplicate responses came from people with characteristics similar to the full sample. Commuting modes included car (46 %), bus but no subway (28 %), and bus and subway (21 %). The median commuting time was 90 minutes round-trip, and was greater than 120 minutes for 1/4 of the respondents. Participation was low despite the raffle. The small percentage of duplicate answers, maybe prompted by the reminding email, had a negligible impact on the results.

Hyperloops, Nuclear Spacecraft, and the New York City Subway

NASA Astrophysics Data System (ADS)

Granade, Stephen

2014-03-01

Frustrated by the speed and high cost-per-mile of the California High-Speed Rail project linking Los Angeles with San Francisco, Elon Musk proposed the Hyperloop: a high-speed train running in a sealed, partially-evacuated tube. Musk released a white paper that described the technology and concluded that the Hyperloop could be built for less than a tenth of a cost of the California High-Speed Rail. Musk's white paper focused heavily on the scientific and technical questions that must be answered, but public transportation is a domain at the intersection of science and society. Public transportation infrastructure is shaped as much by the pressures of government and citizens as by the technology behind the transportation. Tube-based transport like the Hyperloop has been proposed before, but has never gone further than words on a page. Why? Historical examples like the development of the New York City subway and the proposed nuclear-powered Orion spacecraft shed light on the societal barriers that new transportation must overcome, and help illuminate why technology-based answers are not a full response to transportation questions.

Persuasion to use personal protective equipment in constructing subway stations: application of social marketing.

PubMed

Shamsi, Mahmoud; Pariani, Abbas; Shams, Mohsen; Soleymani-nejad, Marzieh

2016-04-01

To study the effects of an intervention based on social marketing to persuade workers to use personal protective equipment (PPE) in constructing subway stations in Isfahan, Iran. This was a quasi-experimental study. Two stations were selected as intervention and control groups. Intervention was designed based on results of a formative research. A free package containing a safety helmet with a tailored message affixed to it, mask and gloves and an educational pamphlet was delivered to the intervention group. After 6 weeks, behaviours in the intervention and control stations were measured using an observational checklist. After the intervention, the percentage of workers who used PPE at the intervention station increased significantly. OR for helmet and mask usage was 7.009 and 2.235, respectively, in the intervention group. Social marketing can be used to persuade workers to use PPE in the workplace. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Model uncertainty of various settlement estimation methods in shallow tunnels excavation; case study: Qom subway tunnel

NASA Astrophysics Data System (ADS)

Khademian, Amir; Abdollahipour, Hamed; Bagherpour, Raheb; Faramarzi, Lohrasb

2017-10-01

In addition to the numerous planning and executive challenges, underground excavation in urban areas is always followed by certain destructive effects especially on the ground surface; ground settlement is the most important of these effects for which estimation there exist different empirical, analytical and numerical methods. Since geotechnical models are associated with considerable model uncertainty, this study characterized the model uncertainty of settlement estimation models through a systematic comparison between model predictions and past performance data derived from instrumentation. To do so, the amount of surface settlement induced by excavation of the Qom subway tunnel was estimated via empirical (Peck), analytical (Loganathan and Poulos) and numerical (FDM) methods; the resulting maximum settlement value of each model were 1.86, 2.02 and 1.52 cm, respectively. The comparison of these predicted amounts with the actual data from instrumentation was employed to specify the uncertainty of each model. The numerical model outcomes, with a relative error of 3.8%, best matched the reality and the analytical method, with a relative error of 27.8%, yielded the highest level of model uncertainty.

Automatic and efficient methods applied to the binarization of a subway map

NASA Astrophysics Data System (ADS)

Durand, Philippe; Ghorbanzadeh, Dariush; Jaupi, Luan

2015-12-01

The purpose of this paper is the study of efficient methods for image binarization. The objective of the work is the metro maps binarization. the goal is to binarize, avoiding noise to disturb the reading of subway stations. Different methods have been tested. By this way, a method given by Otsu gives particularly interesting results. The difficulty of the binarization is the choice of this threshold in order to reconstruct. Image sticky as possible to reality. Vectorization is a step subsequent to that of the binarization. It is to retrieve the coordinates points containing information and to store them in the two matrices X and Y. Subsequently, these matrices can be exported to a file format 'CSV' (Comma Separated Value) enabling us to deal with them in a variety of software including Excel. The algorithm uses quite a time calculation in Matlab because it is composed of two "for" loops nested. But the "for" loops are poorly supported by Matlab, especially in each other. This therefore penalizes the computation time, but seems the only method to do this.

Noise Levels Associated With New York City's Mass Transit Systems

PubMed Central

Gershon, Robyn R. M.; Zeltser, Marina; Canton, Allison; Akram, Muhammad

2009-01-01

Objectives. We measured noise levels associated with various forms of mass transit and compared them to exposure guidelines designed to protect against noise-induced hearing loss. Methods. We used noise dosimetry to measure time-integrated noise levels in a representative sample of New York City mass transit systems (subways, buses, ferries, tramway, and commuter railways) aboard transit vehicles and at vehicle boarding platforms or terminals during June and July 2007. Results. Of the transit types evaluated, subway cars and platforms had the highest associated equivalent continuous average (Leq) and maximum noise levels. All transit types had Leq levels appreciably above 70 A-weighted decibels, the threshold at which noise-induced hearing loss is considered possible. Conclusions. Mass transit noise exposure has the potential to exceed limits recommended by the World Health Organization and the US Environmental Protection Agency and thus cause noise-induced hearing loss among riders of all forms of mass transit given sufficient exposure durations. Environmental noise–control efforts in mass transit and, in cases in which controls are infeasible, the use of personal hearing protection would benefit the ridership's hearing health. PMID:19542046

Uncovering stable and occasional human mobility patterns: A case study of the Beijing subway

NASA Astrophysics Data System (ADS)

Yong, Nuo; Ni, Shunjiang; Shen, Shifei; Chen, Peng; Ji, Xuewei

2018-02-01

There have generally been two kinds of approaches to the empirical study of human mobility. At the group level, some valuable information might be submerged in statistical noise, while due to the diversity of individual purpose and preference, there is still no general statistical regularity of human mobility at the individual level. In this paper, we considered group-level human mobility as the combination of several basic patterns and analyzed the collective mobility by category. Utilizing matrix factorization and correlation analysis, we extracted some of the stable/occasional components from the collective human mobility in the Beijing subway and found that the departure and arrival mobility patterns have different characteristics, both in time and space, under various conditions. We classified individual records into different patterns and analyzed the most likely trip distance by category. The proposed method can decompose stable/occasional mobility patterns from the collective mobility and identify passengers belonging to different patterns, helping us to better understand the origin of different mobility patterns and provide guidance for emergency management of large crowds.

Between subway and spaceship: practical ethics at the outset of the twenty-first century.

PubMed

Benjamin, M

2001-01-01

Moral deliberation involves a constant interplay among specific judgments, general moral values and principles, and background beliefs about the world. We may also construct broad moral theories to explain how our judgments and general commitments hang together, but there is little hope of settling on any one comprehensive moral theory.

10. copy of a construction progress photograph taken by the ...

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

10. copy of a construction progress photograph taken by the Hunkin-Conkey Construction Company, dated October 25, 1916. Photo shows the reinforced concrete subway deck as it appeared shortly after construction. A portion of arch number 12, can be see. Photo courtesy of Cleveland Public Library. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

Final Environmental Assessment: Lodging Improvements

DTIC Science & Technology

2004-06-01

LEVELS {dBA) NOISE LEVELS - r- 110 Rock Band Jet Flyover at 1 000 ft. - f- 100 Gas Lawn Mower at 3 ft. Inside Subway Train (New York) - f- 90...Diesel Truck at 50 ft. Food Blender at 3 ft. Noise Urban Daytime - f- 80 Garbage Disposal at 3 ft. Shouting at 3 ft. ,...... ; Gas Lawn Mower at 1

Saugus River and Tributaries, Lynn Malden, Revere and Saugus, Massachusetts. Flood Damage Reduction. Volume 4. Appendix G. Economics. Appendix H. Socioeconomic.

DTIC Science & Technology

1989-06-01

is not accessible by subway from Boston. Policy guidance for evaluation of recreational facilities for structural flood reduction plans require that...Trapelo Road Waltham, Massachusetts Prepared By: IEP, Inc. P.O. Box 1840 90 Route 6A/Sextant Hill Sandwich , Massachusetts 02563 EPnc. Table of Contents

Engaging Undergraduates in the New York City S-SAFE Internship Program: An Impetus to Raise Geoscience Awareness

ERIC Educational Resources Information Center

Blake, Reginald A.; Liou-Mark, Janet; Blackburn, Noel; Chan, Christopher; Yuen-Lau, Laura

2015-01-01

To engender and raise awareness to the geosciences, a geoscience research project and a corresponding geoscience internship program were designed around plume dispersion dynamics within and above the New York City subway system. Federal, regional, and local agencies partnered with undergraduate students from minority-serving institutions to…

Black and White Racism: An Unobtrusive Experimental Assessment.

ERIC Educational Resources Information Center

Bromley, Stephanie; And Others

This paper presents the results of a study to assess both interracial and intraracial attitudes in a field setting, using two measures: (1) compliance with a request for help, and (2) juridic judgments. Black and white female college students asked black and white Boston subway passengers to read a description of a (bogus) legal case, involving…

Alligators in the Sewers? Really?

ERIC Educational Resources Information Center

Egbert, Joy

2009-01-01

A large number of alligators, flushed down toilets as babies, have grown up and proliferated in the bowels of New York City. Over the years, they have grown in number and size and frequently terrorize those foolish enough to visit the subways. This tale has been making its way around the Internet ever since there's been an Internet. It's wild…

Analysis of Government Accountability Office and Department of Defense Inspector General Reports and Commercial Sources on Service Contracts

DTIC Science & Technology

2010-06-01

subway project seven months ahead of the 36 month schedule, saving HK$14.8 million, of which the government and the contractor each benefited by HK...contractors. DoD IG. United States Department of Defense Inspector General. (2003). Report No. D-2003-113, Franchise business activity contracts for medical

Characteristics of the Built Environment and the Presence of the Norway Rat in New York City: Results From a Neighborhood Rat Surveillance Program, 2008-2010.

PubMed

Johnson, Sarah; Bragdon, Caroline; Olson, Carolyn; Merlino, Mario; Bonaparte, Sancia

2016-06-01

Characteristics of an urban setting such as New York City (NYC), including readily available putrescible waste and ample underground infrastructure, make it highly attractive to the Norway rat (Rattus norvegicus). To identify property and neighborhood characteristics associated with rat presence, recent inspectional results were analyzed from over 77,000 properties in the Bronx and Manhattan. Variables capturing the location and density of factors believed to promote rat populations were tested individually and in combination in models predicting rat activity. We found that property-specific characteristics typically associated with high garbage volume, including large numbers of residential units, public ownership, and open-space designation (parks, outdoor recreation, or vacant land) were the most important factors in explaining increased rat presence across neighborhoods in NYC. Interventions that involved improved garbage management and street sanitation within a designated area reduced the likelihood of finding rats, especially in medium- and high-poverty neighborhoods. Neighborhood characteristics, such as being near a railroad or subway line, having a school nearby, the presence of numerous restaurants, or having older infrastructure, also contributed to the increased likelihood of rats. Our results support the use of built environment data to target community-level interventions and capture emerging rat infestations.

The Fate of Chemical Warfare Agents in the Environment

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

Talmage, Sylvia Smith; Munro, Nancy B; Watson, Annetta Paule

2007-01-01

Chemical Warfare Agents, Second Edition has been totally revised since the successful first edition and expanded to about three times the length, with many new chapters and much more in-depth consideration of all the topics. The chapters have been written by distinguished international experts in various aspects of chemical warfare agents and edited by an experienced team to produce a clear review of the field. The book now contains a wealth of material on the mechanisms of action of the major chemical warfare agents, including the nerve agent cyclosarin, formally considered to be of secondary importance, as well as ricinmore » and abrin. Chemical Warfare Agents, Second Edition discusses the physico-chemical properties of chemical warfare agents, their dispersion and fate in the environment, their toxicology and management of their effects on humans, decontamination and protective equipment. New chapters cover the experience gained after the use of sarin to attack travelers on the Tokyo subway and how to deal with the outcome of the deployment of riot control agents such as CS gas. This book provides a comprehensive review of chemical warfare agents, assessing all available evidence regarding the medical, technical and legal aspects of their use. It is an invaluable reference work for physicians, public health planners, regulators and any other professionals involved in this field.« less

Understanding neighborhood environment related to Hong Kong children's physical activity: a qualitative study using nominal group technique.

PubMed

He, Gang; Cerin, Ester; Huang, Wendy Y; Wong, Stephen H

2014-01-01

Relationships between the neighborhood environment and children's physical activity have been well documented in Western countries but are less investigated in ultra-dense Asian cities. The aim of this study was to identify the environmental facilitators and barriers of physical activity behaviors among Hong Kong Chinese children using nominal group technique. Five nominal groups were conducted among 34 children aged 10-11 years from four types of neighborhoods varying in socio-economic status and walkability in Hong Kong. Environmental factors were generated by children in response to the question "What neighborhood environments do you think would increase or decrease your willingness to do physical activity?" Factors were prioritized in order of their importance to children's physical activity. Sixteen unique environmental factors, which were perceived as the most important to children's physical activity, were identified. Factors perceived as physical activity-facilitators included "Sufficient lighting", "Bridge or tunnel", "Few cars on roads", "Convenient transportation", "Subway station", "Recreation grounds", "Shopping malls with air conditioning", "Fresh air", "Interesting animals", and "Perfume shop". Factors perceived as physical activity-barriers included "People who make me feel unsafe", "Crimes nearby", "Afraid of being taken or hurt at night", "Hard to find toilet in shopping mall", "Too much noise", and "Too many people in recreation grounds". Specific physical activity-related environmental facilitators and barriers, which are unique in an ultra-dense city, were identified by Hong Kong children. These initial findings can inform future examinations of the physical activity-environment relationship among children in Hong Kong and similar Asian cities.

Understanding Swift Trust to Improve Interagency Collaboration in New York City

DTIC Science & Technology

2012-09-01

Performance,” Journal of Managerial Psychology 21, no. 8 (2006): 715, http://www.divisionescolpsic.org/organizacional/ articulos -docs... de -energizing electric power prior to working near energized subway rails or stabilizing vehicles prior to extricating victims, do not seem to be...agency that arrives first. One specific change to CIMS needed is the inclusion of scaffold 193 NYC

Effects of Hydrogen Peroxide on Common Aviation Textiles

DTIC Science & Technology

2009-08-01

efficacious (complete kill of 106 CFU of the spore forming Geobacillus stearothermophilus ) in a narrow-body aircraft fuselage (3), as well as wide-body...disinfectant/ sterilant for transportation vehicles like aircraft, buses, subway trains, ambulances, etc. Although the biological efficacy of STERIS...hydrogen peroxide (VHP)1 technology is of particular interest due to rapid sterilization , easy usage, intrinsic environmental friendliness (i .e

Audio 2008: Audio Fixation

ERIC Educational Resources Information Center

Kaye, Alan L.

2008-01-01

Take a look around the bus or subway and see just how many people are bumping along to an iPod or an MP3 player. What they are listening to is their secret, but the many signature earbuds in sight should give one a real sense of just how pervasive digital audio has become. This article describes how that popularity is mirrored in library audio…

Reducing the Federal Budget: Strategies and Examples, Fiscal Years 1982- 1986.

DTIC Science & Technology

1981-02-01

Small issues are being used with increasing frequency to finance a wide range of facilities including manufacturing plants, fast- food franchises , and...Funding for Amtrak .......... 79 Phasing Out of Conrail Funding ........ 81 Reduction in New Subway Commitments ...... ... 83 Reduced Spending on...Grant ............... 166 Changes in Food Stamp Program . . . . . . . 168 Recoupment of Food Stamp Benefits . . . . .. 171 Change in the Low Income

There Are No Subways in Lickingville: Metropolitan Models Don't Work for Rural People.

ERIC Educational Resources Information Center

Hillman, Arnold

This book presents an overview of the problems facing rural America and offers solutions at the national, state, and local levels. The combination of public lack of awareness and metropolitan-centered authority has created a view of rural America and its people that is contrary to both the data and actual living conditions. Rural education has…

The New York City Subways: The First Ten Years. A Library Research Exercise Using a Computer.

ERIC Educational Resources Information Center

Machalow, Robert

This document presents a library research exercise developed at York College which uses the Apple IIe microcomputer and word processing software--the Applewriter--to teach library research skills. Unlike some other library research exercises on disk, this program allows the student to decide on alternative approaches to solving the given problem:…

Beware of "Black" the Ripper! Racism, Representation, and Building Antiracist Pedagogy

ERIC Educational Resources Information Center

DeLeon, Abraham P.

2006-01-01

The cover of the June 15, 2006, edition of the "New York Post" reported that Kenny Alexis, who was dubbed "The Ripper," was apprehended after he attacked several people in a New York City subway. Alexis was shown standing ominously with several white police officers behind him. At first, the story seems to describe a random and…

Aum Shinrikyo's Chemical and Biological Weapons: More Than Sarin.

PubMed

Tu, A T

2014-07-01

The radical religious group Aum Shinrikyo was founded in Japan in the 1980s and grew rapidly in the 1990s. Aum members perpetrated a mass murder in Matsumoto City in 1994, where they used sarin as a chemical weapon to poison approximately 500 civilians. On March 20, 1995, Aum deployed sarin in an even larger terrorist attack on the Tokyo Subway System, which poisoned some 6,000 people. After the Tokyo Subway attack, the Japanese Police arrested the sect's senior members. From 2005 through 2011, 13 of these senior members were sentenced to death. In this article, aspects of Aum's chemical and biological terrorism are reviewed. Sarin production efforts by the sect are described, including how the degradation product of sarin in soil, methylphosphonic acid, enabled the detection of sarin production sites. Also, Aum's chemical-warfare agents other than sarin are described, as are its biological weapons. The author was permitted by the Japanese government to interview Dr. Tomomasa Nakagawa, one of the senior members of Aum Shinrikyo. From Dr. Nakagawa the author obtained valuable inside information about Aum's chemical and biological weapons programs. Copyright © 2014 Central Police University.

Human mobility in space from three modes of public transportation

NASA Astrophysics Data System (ADS)

Jiang, Shixiong; Guan, Wei; Zhang, Wenyi; Chen, Xu; Yang, Liu

2017-10-01

The human mobility patterns have drew much attention from researchers for decades, considering about its importance for urban planning and traffic management. In this study, the taxi GPS trajectories, smart card transaction data of subway and bus from Beijing are utilized to model human mobility in space. The original datasets are cleaned and processed to attain the displacement of each trip according to the origin and destination locations. Then, the Akaike information criterion is adopted to screen out the best fitting distribution for each mode from candidate ones. The results indicate that displacements of taxi trips follow the exponential distribution. Besides, the exponential distribution also fits displacements of bus trips well. However, their exponents are significantly different. Displacements of subway trips show great specialties and can be well fitted by the gamma distribution. It is obvious that human mobility of each mode is different. To explore the overall human mobility, the three datasets are mixed up to form a fusion dataset according to the annual ridership proportions. Finally, the fusion displacements follow the power-law distribution with an exponential cutoff. It is innovative to combine different transportation modes to model human mobility in the city.

A multiscale-based approach for composite materials with embedded PZT filaments for energy harvesting

NASA Astrophysics Data System (ADS)

El-Etriby, Ahmed E.; Abdel-Meguid, Mohamed E.; Hatem, Tarek M.; Bahei-El-Din, Yehia A.

2014-03-01

Ambient vibrations are major source of wasted energy, exploiting properly such vibration can be converted to valuable energy and harvested to power up devices, i.e. electronic devices. Accordingly, energy harvesting using smart structures with active piezoelectric ceramics has gained wide interest over the past few years as a method for converting such wasted energy. This paper provides numerical and experimental analysis of piezoelectric fiber based composites for energy harvesting applications proposing a multi-scale modeling approach coupled with experimental verification. The multi-scale approach suggested to predict the behavior of piezoelectric fiber-based composites use micromechanical model based on Transformation Field Analysis (TFA) to calculate the overall material properties of electrically active composite structure. Capitalizing on the calculated properties, single-phase analysis of a homogeneous structure is conducted using finite element method. The experimental work approach involves running dynamic tests on piezoelectric fiber-based composites to simulate mechanical vibrations experienced by a subway train floor tiles. Experimental results agree well with the numerical results both for static and dynamic tests.

The modeling of attraction characteristics regarding passenger flow in urban rail transit network based on field theory

PubMed Central

Jia, Limin

2017-01-01

Aimed at the complicated problems of attraction characteristics regarding passenger flow in urban rail transit network, the concept of the gravity field of passenger flow is proposed in this paper. We establish the computation methods of field strength and potential energy to reveal the potential attraction relationship among stations from the perspective of the collection and distribution of passenger flow and the topology of network. As for the computation methods of field strength, an optimum path concept is proposed to define betweenness centrality parameter. Regarding the computation of potential energy, Compound Simpson’s Rule Formula is applied to get a solution to the function. Taking No. 10 Beijing Subway as a practical example, an analysis of simulation and verification is conducted, and the results shows in the following ways. Firstly, the bigger field strength value between two stations is, the stronger passenger flow attraction is, and the greater probability of the formation of the largest passenger flow of section is. Secondly, there is the greatest passenger flow volume and circulation capacity between two zones of high potential energy. PMID:28863175

Risk analysis for rumor propagation in metropolises based on improved 8-state ICSAR model and dynamic personal activity trajectories

NASA Astrophysics Data System (ADS)

Zhang, N.; Huang, H.; Duarte, M.; Zhang, J.

2016-06-01

Social media has developed extremely fast in metropolises in recent years resulting in more and more rumors disturbing our daily lives. Knowing the characteristics of rumor propagation in metropolises can help the government make efficient rumor refutation plans. In this paper, we established a dynamic spatio-temporal comprehensive risk assessment model for rumor propagation based on an improved 8-state ICSAR model (Ignorant, Information Carrier, Information Spreader, Advocate, Removal), large personal activity trajectory data, and governmental rumor refutation (anti-rumor) scenarios. Combining these relevant data with the 'big' traffic data on the use of subways, buses, and taxis, we simulated daily oral communications among inhabitants in Beijing. In order to analyze rumor and anti-rumor competition in the actual social network, personal resistance, personal preference, conformity, rumor intensity, government rumor refutation and other influencing factors were considered. Based on the developed risk assessment model, a long-term dynamic rumor propagation simulation for a seven day period was conducted and a comprehensive rumor propagation risk distribution map was obtained. A set of the sensitivity analyses were conducted for different social media and propagation routes. We assessed different anti-rumor coverage ratios and the rumor-spreading thresholds at which the government started to launch anti-rumor actions. The results we obtained provide worthwhile references useful for governmental decision making towards control of social-disrupting rumors.

Bottleneck effects on the bidirectional crowd dynamics

NASA Astrophysics Data System (ADS)

Yang, Xiao-Xia; Dong, Hai-Rong; Yao, Xiu-Ming; Sun, Xu-Bin

2016-12-01

The bottleneck effect on bidirectional crowd dynamics is of great theoretical and practical significance, especially for the designing of corridors in public places, such as subway stations or airports. Based on the famous social force model, this paper investigates the bottleneck effects on the free flow dynamics and breakdown phenomenon under different scenarios, in which different corridor shapes and inflow ratios are considered simultaneously. Numerical simulation finds an interesting self-organization phenomenon in the bidirectional flow, a typical characteristic of such a phenomenon is called lane formation, and the existence of which is independent of the corridor’s shape and inflow rate. However, the pattern of the lane formed by pedestrian flow is related to the corridor’s shape, and the free flow efficiency has close relationship with the inflow rate. Specifically, breakdown phenomenon occurs when inflows from both sides of the corridor are large enough, which mostly originates from the bottleneck and then gradually spreads to the other regions. Simulation results further indicate that the leaving efficiency becomes low as breakdown occurs, and the degree of congestion is proportional to the magnitude of inflow. The findings presented in this paper match well with some of our daily observations, hence it is possible to use them to provide us with theoretical suggestions in design of infrastructures. Project supported jointly by the National Natural Science Foundation of China (Grant Nos. 61322307 and 2016YJS023).

Study Abroad in a Time of Terror; U.S. Student Experiences in Brussels

ERIC Educational Resources Information Center

Gleye, Paul

2017-01-01

On the morning of March 22, 2016, two men pushed luggage trolleys containing suitcases laden with nail bombs into the departure hall of the Brussels airport and detonated them. About an hour later, a third suicide bomber detonated a nail bomb in a subway train at the Maelbeek metro station near central Brussels. These attacks claimed the lives of…

121. View of water filters, water from which is used ...

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

121. View of water filters, water from which is used to cool bearings of turbine-generator units in Generator Room above; looking north. This water filter is for turbine-generator unit no. 1, and is located in the subway. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

Industry Studies 2002: Construction

DTIC Science & Technology

2002-01-01

Jacksonville, FL Rotary Club of San Juan, San Juan, PR Tren Urbano Subway Project, San Juan, PR U.S. Army South, San Juan, PR U.S. Coast Guard Housing Project...Bechtel Corporation (IBM Plant Construction Site), Shanghai American Chamber of Commerce, Shanghai Urban Planning Exhibit, Shanghai 3 INTRODUCTION The...of states have or are working on a statewide or agency-wide privatization plan , including California, Maryland, Massachusetts, Michigan and

Tokyo terror and chemical arms control

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

Keeny, S.M. Jr.

The nerve gas attack in the Tokyo subway underscores the extreme vulnerability of urban society to terrorist attacks. The best defense is improved intelligence of potential terrorists and domestic laws permitting pre-emptive action when there is probable cause. If the 1993 Chemical Weapons Convention (CWC) were in force, all 159 signatories would be required to have such laws. The author examies the threat and provides some political insights.

Terrorism Risk Modeling for Intelligence Analysis and Infrastructure Protection

DTIC Science & Technology

2007-01-01

comparatively high risk of CBRN attacks. Estimates of sabotage risk are highly dependent on proximity of nuclear power plants , chemical plants , or oil...and casinos, airports, nuclear power plants 3 Military, train and subway stations, stadiums, bridges and tunnels 4 Industrial facilities, oil and...airspace zones 8 Power plants , dams, railway networks levels. Collecting and incorporating such data for specific localities or industry sectors would

Environmental Assessment Use of Golden Triangle Regional Airport by 14th Flying Training Wing Aircraft

DTIC Science & Technology

2004-03-01

NOISE LEVEL COMMON INDOOR NOISE LEVELS (dBA) NOISE LEVELS - .- 110 Rock Band - 1- 100 Gas Lawn Mower at 3 ft . Inside Subway Train (New York...1- 90 Diesel Truck at 50 ft. Food Blender at 3 ft. Noise Urban Daytime - 1- 80 Garbage Disposal at 3 ft. Shouting at 3 ft. Gas Lawn Mower at 100ft

Deactivation of the SR-71 Program at Beale Air Force Base, California

DTIC Science & Technology

1989-07-01

110 Rock Band Jet, F vover at 1000 Feet -- 100 Inside Subway Tran iNew York) Gas Lawn Mower at 3 Feet - •90 Dieses Truck at 50 Feet Food Blender...at 3 Feet Noisy Urban Daytime - - 80 Garbage Dsciosai at 3 Feet Shouting at 3 Feet Gas Lawn Mower at 100 Feet - 70 Vacuum Cleaner at 10 Peet Commercial

Environmental Assessment T-1, T-6, and T-37 Aircraft Operations at Perry Municipal Airport

DTIC Science & Technology

2006-04-01

110 Rock Band - 1- 100 Inside Subway Train (New York) Gas Lawn Mower at 3 ft. Diesel Truck at 50 ft. - 1- 90 Food Blender at 3 ft. Noisy Urban...Daytime - 1- 80 Garbage Disposal at 3 ft. Shouting at 3 ft. Gas Lawn Mower at 100ft. Vacuum Cleaner at 10ft. - 1- 70 Commercial Area Normal

Combating Terrorism in a Globalized World

DTIC Science & Technology

2002-05-01

warhead is detonated in London or a smallpox outbreak in Tokyo or a nerve agent is introduced into the Washington, DC, subway system. An initiative...and convey a more positive image of the Western world. Furthermore, the civilized world should work together to provide disen- franchised youth...59 Economic growth in developing countries leads to reduced poverty, increased food security, and higher standards of living, including better health

Understanding Neighborhood Environment Related to Hong Kong Children’s Physical Activity: A Qualitative Study Using Nominal Group Technique

PubMed Central

He, Gang; Cerin, Ester; Huang, Wendy Y.; Wong, Stephen H.

2014-01-01

Background Relationships between the neighborhood environment and children’s physical activity have been well documented in Western countries but are less investigated in ultra-dense Asian cities. The aim of this study was to identify the environmental facilitators and barriers of physical activity behaviors among Hong Kong Chinese children using nominal group technique. Methods Five nominal groups were conducted among 34 children aged 10–11 years from four types of neighborhoods varying in socio-economic status and walkability in Hong Kong. Environmental factors were generated by children in response to the question “What neighborhood environments do you think would increase or decrease your willingness to do physical activity?” Factors were prioritized in order of their importance to children’s physical activity. Results Sixteen unique environmental factors, which were perceived as the most important to children’s physical activity, were identified. Factors perceived as physical activity-facilitators included “Sufficient lighting”, “Bridge or tunnel”, “Few cars on roads”, “Convenient transportation”, “Subway station”, “Recreation grounds”, “Shopping malls with air conditioning”, “Fresh air”, “Interesting animals”, and “Perfume shop”. Factors perceived as physical activity-barriers included “People who make me feel unsafe”, “Crimes nearby”, “Afraid of being taken or hurt at night”, “Hard to find toilet in shopping mall”, “Too much noise”, and “Too many people in recreation grounds”. Conclusions Specific physical activity-related environmental facilitators and barriers, which are unique in an ultra-dense city, were identified by Hong Kong children. These initial findings can inform future examinations of the physical activity-environment relationship among children in Hong Kong and similar Asian cities. PMID:25187960

Construction. A Report on the Industry

DTIC Science & Technology

2004-06-01

Transportation and Tres Urbano Subway Project, San Juan, Puerto Rico U.S. Corps of Engineers, San Juan, Puerto Rico U.S. Corps of Engineers, Mobile...recently approved a plan to privatize construction of over 6,000 miles of expressways through the use of a build, transfer, and operate options.xl...security standards in Federal facilities, including an aggressive plan to build and renovate embassies and consular offices worldwide.xlv The

JPRS Report, China 1989 Selected Provincial Economic Reports

DTIC Science & Technology

1989-08-23

bumper harvest, and the supply of grain and the main nonstaple foods continued to increase. Upon implementing the responsibility system of linking...grain production topped 2,346,000 tons, surpassing the plan by 24,600 tons. Output of all of the main nonstaple foods exceeded the plan. Seeding...1988 were mainly urban infrastructure construction projects, such as the Fuxingmen to Bawangfen Subway and the Gaobeidian Sewage Treatment Plant

The Use of Films as Suitable Packaging Materials for Minimally Processed Foods

DTIC Science & Technology

1994-08-01

subway stations. Many of these lunch box vending machines are serving lunches with no refrigeration. Ihe secret is the application of antimicrobial...Ooating: Convenience foods with different components bearing different water activity, oil content, or other migrating components (e.g., a sandwich ...growing in the barrier properties of edible film such as protein/lipid complexes that prevent dehydration of cut vegetables or a sandwich filling from

Medical triage for WMD incidents incidents: an adaptation of daily triage.

PubMed

Donohue, Dave

2008-05-01

It's 2000 HRS on a Friday evening. You're assigned to an ALS engine company, and you're just settling down after a busy day when you're dispatched along with a BLS ambulance to a report of a sick person outside a local club where they're holding a concert. During your response, dispatch advises that they're receiving multiple calls on the incident and are dispatching a second BLS ambulance to the call. * As you turn the corner and approach the scene, you notice a haze in the air coming from an industrial site on the same side of the street and see approximately 200 people exiting the club in haste. Several dozen patrons line the street between the club and the subway station. They're coughing and crying, and several are vomiting. * The driver stops the engine in front of the subway entrance, which is located approximately 500 feet from the club and uphill and upwind from the haze. The scene is overwhelming, even to the captain, who turns to you-as the paramedic on the crew-and asks what you want done first. Your first thought is, Triage. But you know that triaging these patients is more complicated than your everyday two-car collision.

Characteristics of noise-canceling headphones to reduce the hearing hazard for MP3 users.

PubMed

Liang, Maojin; Zhao, Fei; French, David; Zheng, Yiqing

2012-06-01

Three pairs of headphones [standard iPod ear buds and two noise-canceling headphones (NCHs)] were chosen to investigate frequency characteristics of noise reduction, together with their attenuation effects on preferred listening levels (PLLs) in the presence of various types of background noise. Twenty-six subjects with normal hearing chose their PLLs in quiet, street noise, and subway noise using the three headphones and with the noise-canceling system on/off. Both sets of NCHs reduced noise levels at mid- and high-frequencies. Further noise reductions occurred in low frequencies with the noise canceling system switched on. In street noise, both NCHs had similar noise reduction effects. In subway noise, better noise reduction effects were found in the expensive NCH and with noise-canceling on. A two way repeated measures analysis of variance showed that both listening conditions and headphone styles were significant influencing factors on the PLLs. Subjects tended to increase their PLLs as the background noise level increased. Compared with ear buds, PLLs obtained from NCHs-on in the presence of background noise were reduced up to 4 dB. Therefore, proper selection and use of NCHs appears beneficial in reducing the risk of hearing damage caused by high music listening levels in the presence of background noise.

Exposure assessment in Beijing, China: biological agents, ultrafine particles, and lead.

PubMed

Dong, Shuofei; Yao, Maosheng

2010-11-01

In this study, air samples were taken using a BioSampler and gelatin filters from six sites in Beijing: office, hospital, student dormitory, train station, subway, and a commercial street. Dust samples were also collected using a surface sampler from the same environments. Limulus amoebocyte lysate (LAL) and Glucatell assays were used to quantify sample endotoxin and (1,3)-β-d-glucan concentration levels, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to measure the dust mite allergens (Der p 1 and Der f 1). Ultrafine particle and lead concentrations in these sampling sites were also measured using P-Trak and atomic absorption spectrometer, respectively. Analysis of variance (ANOVA) and linear regression analysis were used to analyze the concentration data. Higher culturable bacteria (12,639 CFU/m3) and fungi (1,806 CFU/m3) concentrations were observed for the train station and the subway system, respectively. For the rest of sampling sites, their concentrations were comparable to those found in western countries, ranging from 990 to 2,276 CFU/m3 for bacteria, and from 119 to 269 CFU/m3 for fungi. ANOVA analysis indicated that there were statistically significant differences between the culturable bacterial and fungal concentration levels obtained for different sites (p value=0.0001 and 0.0047). As for dust allergens, endotoxin, and (1,3)-β-D-glucan, their concentrations also seemed to be comparable to those found in the developed countries. Airborne allergen concentrations ranged from 16 to 68 ng/m3. The dust-borne allergen concentration was observed to range from 0.063 to 0.327 ng/mg. As for endotoxin, the highest airborne concentration of 25.24 ng/m3 was observed for the commercial street, and others ranged from 0.0427 to 0.1259 ng/m3. And dust-borne endotoxin concentration ranged from 58.83 to 6,427.4 ng/mg. For (1,3)-β-D-glucan, the airborne concentration ranged from 0.02 to 1.2 ng/m3. Linear regression analyses showed that there existed poor correlations between those in airborne and dust-borne states (R2=0.002~0.43). In our study, the lowest ultrafine particle concentration about 5,203 pt/cm3 was observed in office and the highest was observed at the train station, up to 32,783 pt/cm3. Lead concentration was shown to range from 80 to 170 ng/mg with the highest also observed at the train station. The information provided in this work can be used to learn the general situation of relevant health risks in Beijing. And the results here suggested that when characterizing exposure both airborne and dust-borne as well as the environments should be considered.

RFID Meets GWOT: Considering a New Technology for a New Kind of War

DTIC Science & Technology

2006-06-01

creating a tag that will enable commuters to travel conveniently throughout the city’s subway system. While these items have yet to come, they are... food items that will let your refrigerator know what is missing inside. In turn, your refrigerator will communicate to your cell phone that you need...regular routines. Additionally, businesses reopened and outside investors sought new opportunities as they brought the island’s first franchise

Exposure to ultrafine particles in different transport modes in the city of Rome.

PubMed

Grana, Mario; Toschi, Nicola; Vicentini, Laura; Pietroiusti, Antonio; Magrini, Andrea

2017-09-01

There is evidence of adverse health impacts from human exposure to particulate air pollution, including increased rates of respiratory and cardiovascular illness, hospitalizations, and pre-mature mortality. Most recent hypotheses assign an important role to ultrafine particles (UFP) (<0.1 μm) and to associated transition metals (in particular Fe). In a large city like Rome, where many active people spend more than one hour per day in private or public transportation, it may be important to evaluate the level of exposure to harmful pollutants which occurs during urban travelling. In this context, the aim of this work was to examine the relative contribution of different transport modes to total daily exposure. We performed experimental measurements during both morning and evening traffic peak hours throughout the winter season (December 2013-March 2014), for a total of 98 trips. Our results suggest that the lowest UFP exposures are experienced by underground train commuters, with an average number concentration of 14 134 cm -3 , and are largely a reflection of the routes being at greater distance from vehicular traffic. Motorcyclists experienced significantly higher average concentrations (73 168 cm -3 ) than all other exposure classes, and this is most likely a result of the presence of high-concentration and short-duration peaks which do not occur when the same routes are traveled by car. UFP concentrations in subway train environments were found to be comparable to urban background levels. Still, in underground trains we found the highest values of PM 10 mass concentration with a maximum value of 422 μg/m 3 . PM 10 concentration in trains was found to be four and two times higher than what was measured in car and motorbike trips, respectively. Transport mode contribution to total integrated UFP daily exposure was found to be 16.3%-20.9% while travelling by car, 28.7% for motorbike trips, and 8.7% for subway trips. Due to lower exposure times, commuting by car and motorbike is comparable to other daily activities in terms of exposure. Our data can provide relevant information for transport decision-making and increase environmental awareness in the hope that the information about inhaled pollutants can translate into a more rational approach to urban travelling. Copyright © 2017 Elsevier Ltd. All rights reserved.

a New Multimodal Multi-Criteria Route Planning Model by Integrating a Fuzzy-Ahp Weighting Method and a Simulated Annealing Algorithm

NASA Astrophysics Data System (ADS)

Ghaderi, F.; Pahlavani, P.

2015-12-01

A multimodal multi-criteria route planning (MMRP) system provides an optimal multimodal route from an origin point to a destination point considering two or more criteria in a way this route can be a combination of public and private transportation modes. In this paper, the simulate annealing (SA) and the fuzzy analytical hierarchy process (fuzzy AHP) were combined in order to find this route. In this regard, firstly, the effective criteria that are significant for users in their trip were determined. Then the weight of each criterion was calculated using the fuzzy AHP weighting method. The most important characteristic of this weighting method is the use of fuzzy numbers that aids the users to consider their uncertainty in pairwise comparison of criteria. After determining the criteria weights, the proposed SA algorithm were used for determining an optimal route from an origin to a destination. One of the most important problems in a meta-heuristic algorithm is trapping in local minima. In this study, five transportation modes, including subway, bus rapid transit (BRT), taxi, walking, and bus were considered for moving between nodes. Also, the fare, the time, the user's bother, and the length of the path were considered as effective criteria for solving the problem. The proposed model was implemented in an area in centre of Tehran in a GUI MATLAB programming language. The results showed a high efficiency and speed of the proposed algorithm that support our analyses.

The North Caucasus Insurgency: Dead or Alive

DTIC Science & Technology

2017-02-01

Shvedov, a liberal Rus- sian journalist and expert on the North Caucasus, stat- ed at the time that “the number of bombings , terrorist attacks and murders...crowded subway stations in Mos- cow were targeted by suicide bombers, resulting in 3 the deaths of 40 civilians. In January 2011, a bomb ex- ploded in...Moscow’s busy Domodedovo International Airport, leaving 37 dead. In 2013, three suicide bomb - ings on October 21, December 29, and December 30, shook

Comparative Kinetics and Distribution to Target Tissues of Organophosphates Using Physiologically - Based Pharmacokinetic Modeling

DTIC Science & Technology

2008-03-01

throughout history where nerve agents have been used on human populations, such as the subway bombing in Tokyo and Matsumoto, Japan. Data can be...kidney, fat, diaphragm, arterial blood, venous blood, bronchial passages, and the skin. The remaining tissues will be lumped together as either slowly...were then further developed as a weapon, whose primary effect is on the central nervous system. These agents are tabun, sarin, soman, and VX. They

The Army Conference Policy: Curing the Symptom Instead of the Disease

DTIC Science & Technology

2013-03-01

graffiti was symbolic of the collapse of the system,” Gunn implemented a program to have cars on each subway line cleaned in a methodical fashion . If...Unbecoming A Rational Government,” Forbes Online , http://www/forbes.com/sites.richardsalsman/2013/01/17/debt-ceiling-gimmickry- is-unbecoming-a-rational...The Washington Post, April 4, 2012. 21 Tom Shoop , “Report details ‘excessive and wasteful’ conference spending at GSA,” Government Executive

Counter Radicalization and Recruitment to Al-Qaeda: Fighting the War of Deeds

DTIC Science & Technology

2014-06-01

Damjan al Dawasari, Abu Hafs al Shahri, Aslam Awan; • Suicide operations chiefs: Wali Mohammed; • High-level leaders: Hakimullah Mehsud, Bait- ullah...solicit- ing others to commit violence.35 • Najibullah Zazi, for the September 2009 at- tempted suicide attack in New York’s subway system...bombs in a suicide attack or set off timber bombs in crowded areas. . . . Prosecutor Altman said the plot was “on a scale potentially greater” than

AL Qaeda, Trends in Terrorism and Future Potentialities: An Assessment

DTIC Science & Technology

2003-05-01

constituency? Has it become a franchise operation with like-minded local representatives independently advancing the parent organization’s goals or does it...More than 600,000 Iraqi children have died due to lack of food and medicine and as result of the unjustifiable aggression (sanction) imposed on Iraq and...attack on the New York City subway ; the July 4 shooting at Los Angeles International Airport by a naturalized American-born who had emigrated from

Fuzzy logic controllers: A knowledge-based system perspective

NASA Technical Reports Server (NTRS)

Bonissone, Piero P.

1993-01-01

Over the last few years we have seen an increasing number of applications of Fuzzy Logic Controllers. These applications range from the development of auto-focus cameras, to the control of subway trains, cranes, automobile subsystems (automatic transmissions), domestic appliances, and various consumer electronic products. In summary, we consider a Fuzzy Logic Controller to be a high level language with its local semantics, interpreter, and compiler, which enables us to quickly synthesize non-linear controllers for dynamic systems.

Nonproliferation and Threat Reduction Assistance: U.S. Programs in the Former Soviet Union

DTIC Science & Technology

2012-03-06

The March 1995 nerve agent attack in the Tokyo subway system by the Aum Shinryo cult raised the profile of this type of threat. 19 The report went...had not yet produced any commercial successes . DOE responded by stating that IAP had temporarily employed thousands of scientists in around 170...continued, coordinated success for the programs requires “active political engagement at the White House, cabinet, and sub-cabinet political appointee

Health monitoring for subway station structure by fiber Bragg grating sensors

NASA Astrophysics Data System (ADS)

Zhou, Yao; Wang, Yuan-Feng; Han, Bing; Zhou, Zhi

2008-03-01

Fiber Bragg grating (FBG) sensors hold a great deal of potential for structural monitoring because of their high sensitivity and exceptional stability for long-term monitoring. FBG sensors have been applied to sense a number of physical measurands including strain, temperature, pressure etc. These applications are based on the same principle, i.e. the measurement of Bragg wavelength shift caused by the measurands. The characters and principle of FBG sensors have been introduced in detail. The relative experiment is done. The results show that FBG sensors have high sensitivity and long-term stability. It is feasible to use the sensors to the structural health monitoring (SHM). Cement hydration produces heat, which may provoke important temperature rises in massive structures. Such a high temperature may be a factor for cracking during the cooling phase. Thus, it is important to be able to calculate and control the heat to be produced by a given concrete at the mixture-proportioning stage. Theory of heat of hydration is also introduced in this paper. FBG sensors have been applied successfully in health monitoring for Guomao subway station structure. Compared with results measured by vibrating wire sensors and computed by finite element method, the monitoring results show temperature and strains can be accurately measured by FBG sensors. It is convenient to study on heat of hydration of massive concrete and guide structural design.

An evaluation of the accuracy of the Federal Transit Administration approved, groundborne noise and vibration prediction model for rail transit systems; a case study for a new subway line using post construction, transit operation measurements

NASA Astrophysics Data System (ADS)

Carman, Richard A.; Reyes, Carlos H.

2005-09-01

The groundborne noise and vibration model developed by Nelson and Saurenman in 1984, now recognized by the Federal Transit Administration as the approved model for new transit system facilities, is entering its third decade of use by engineers and consultants in the transit industry. The accuracy of the model has been explored in the past (e.g., Carman and Wolfe). New data obtained for a recently completed extension to a major heavy rail transit system provides an opportunity to evaluate the accuracy of the model once more. During the engineering design phase of the project, noise and vibration predictions were performed for numerous buildings adjacent to the new subway line. The values predicted by the model were used to determine the need for and type of noise and/or vibration control measures. After the start of transit operations on the new line, noise and vibration measurements were made inside several of the buildings to determine whether the criteria were in fact achieved. The measurement results are compared with the values predicted by the model. The predicted and measured, overall noise and vibration levels show very good agreement, whereas the spectral comparisons indicate some differences. Possible reasons for these differences are offered.

A multivariate study for characterizing particulate matter (PM(10), PM(2.5), and PM(1)) in Seoul metropolitan subway stations, Korea.

PubMed

Kwon, Soon-Bark; Jeong, Wootae; Park, Duckshin; Kim, Ki-Tae; Cho, Kyung Hwa

2015-10-30

Given that around eight million commuters use the Seoul Metropolitan Subway (SMS) each day, the indoor air quality (IAQ) of its stations has attracted much public attention. We have monitored the concentration of particulate matters (PMx) (i.e., PM10, PM2.5, and PM1) in six major transfer stations per minute for three weeks during the summer, autumn, and winter in 2014 and 2015. The data were analyzed to investigate the relationship between PMx concentration and multivariate environmental factors using statistical methods. The average PM concentration observed was approximately two or three times higher than outdoor PM10 concentration, showing similar temporal patterns at concourses and platforms. This implies that outdoor PM10 is the most significant factor in controlling indoor PM concentration. In addition, the station depth and number of trains passing through stations were found to be additional influences on PMx. Principal component analysis (PCA) and self-organizing map (SOM) were employed, through which we found that the number of trains influences PM concentration in the vicinity of platforms only, and PMx hotspots were determined. This study identifies the external and internal factors affecting PMx characteristics in six SMS stations, which can assist in the development of effective IAQ management plans to improve public health. Copyright © 2015 Elsevier B.V. All rights reserved.

A pragmatic trial in the Rio de Janeiro subway to capture smokers for a quitline: methodological challenges and opportunities.

PubMed

Szklo, André Salem; da Silva Freire Coutinho, Evandro; Reichenheim, Michael Eduardo

2012-01-01

According to the World Health Organization, smoking is an important cause of death worldwide. To encourage smoking cessation, persuasive messages can be used to raise smokers' risk perception. This article discusses challenges and solutions in designing a study to evaluate the effect of two different communication strategies ("gains from quitting" vs. "losses from continuing smoking") in encouraging calls to a quitline. The authors conducted an intervention study in two subway stations for 4 weeks, considering only 1 strategy per station. Large posters containing non-age-specific images and texts, on the basis of the theme"shortness of breath," were displayed on central dividing columns on the boarding platforms. Call rates from the selected stations, and respective rate ratios, overall and per study week, were calculated. Passengers who were smokers, exposed to the positive-content message, called on average 1.7 times more often than did those exposed to the negative-content message (p = .01). Moreover, call rate ratios did not decline over the 4 weeks of the study (p = .40). The effectiveness findings suggest that antismoking campaigns could use positive-content messages in order to recruit a larger smoker population. The proposed methodology can also be used to evaluate effectiveness of messages for "capturing" individuals with other health problems (e.g., alcohol abuse), thereby increasing its potential impact.

2013 R&D 100 Award: DNATrax could revolutionize air quality detection and tracking

ScienceCinema

Farquar, George

2018-01-16

A team of LLNL scientists and engineers has developed a safe and versatile material, known as DNA Tagged Reagents for Aerosol Experiments (DNATrax), that can be used to reliably and rapidly diagnose airflow patterns and problems in both indoor and outdoor venues. Until DNATrax particles were developed, no rapid or safe way existed to validate air transport models with realistic particles in the range of 1-10 microns. Successful DNATrax testing was conducted at the Pentagon in November 2012 in conjunction with the Pentagon Force Protection Agency. This study enhanced the team's understanding of indoor ventilation environments created by heating, ventilation and air conditioning (HVAC) systems. DNATrax are particles comprised of sugar and synthetic DNA that serve as a bar code for the particle. The potential for creating unique bar-coded particles is virtually unlimited, thus allowing for simultaneous and repeated releases, which dramatically reduces the costs associated with conducting tests for contaminants. Among the applications for the new material are indoor air quality detection, for homes, offices, ships and airplanes; urban particulate tracking, for subway stations, train stations, and convention centers; environmental release tracking; and oil and gas uses, including fracking, to better track fluid flow.

2013 R&D 100 Award: DNATrax could revolutionize air quality detection and tracking

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

Farquar, George

A team of LLNL scientists and engineers has developed a safe and versatile material, known as DNA Tagged Reagents for Aerosol Experiments (DNATrax), that can be used to reliably and rapidly diagnose airflow patterns and problems in both indoor and outdoor venues. Until DNATrax particles were developed, no rapid or safe way existed to validate air transport models with realistic particles in the range of 1-10 microns. Successful DNATrax testing was conducted at the Pentagon in November 2012 in conjunction with the Pentagon Force Protection Agency. This study enhanced the team's understanding of indoor ventilation environments created by heating, ventilationmore » and air conditioning (HVAC) systems. DNATrax are particles comprised of sugar and synthetic DNA that serve as a bar code for the particle. The potential for creating unique bar-coded particles is virtually unlimited, thus allowing for simultaneous and repeated releases, which dramatically reduces the costs associated with conducting tests for contaminants. Among the applications for the new material are indoor air quality detection, for homes, offices, ships and airplanes; urban particulate tracking, for subway stations, train stations, and convention centers; environmental release tracking; and oil and gas uses, including fracking, to better track fluid flow.« less

Environmental Assessment of the Privatization of Military Family Housing, Fairchild Air Force Base, Washington

DTIC Science & Technology

2006-05-01

Subway Train (New York) 9° Food Blender at 3 ft. 80 Garbage Disposal at 3 ft. Shouting at 3 ft. 70 Vacuum Cleaner at 10 ft. Normal Speech 60 at...1899. The Natural Resources Conservation Service (NRCS) has developed procedures for identifying wetlands for compliance with the Food Security Act of...organic litter and wood to aquatic systems, nutrient retention and cycling, wildlife habitat, and food -web support for a wide range of aquatic and

Strategic Studies Quarterly, Volume 4, Number 3, Fall 2010

DTIC Science & Technology

2010-01-01

Story of the Aum Doomsday Cult, from the Subways of Tokyo to the Nuclear Arsenals of Russia (New York: Crown Publishers, 1996 ), 108-12. 32. Lt Col John...Attraction," Journal of Personality andSocial Psychology󈨊, no. 2 (February 1996 ). 26. As Siebold and Lindsay put it, "A central tenet of current [1999...Ralph M. Carney, eds., Out in Force: Sexual Orientation and the Miliuiry (Chicago: University of Chicago Press, 1996 ), 166. 29. Om Prakash, "The

TsAGI The Center of Aviation Science and Mechanics,

DTIC Science & Technology

1979-10-23

elements and an aircraft as a whole . In December 1925 TsAGI began operation of the largest wind tunnel in the world, at that time, the T-I - T-II wind...analysis methods for aviation structures were developed and the causes of the onset of vibrations in aircraft were investigated. V. N. Belyayev, A. Yu...compressors and other machines and devices were developed and studied in detail. A large number of enterprises, coal mines and the Moscow subway received

Subway platform air quality: Assessing the influences of tunnel ventilation, train piston effect and station design

NASA Astrophysics Data System (ADS)

Moreno, T.; Pérez, N.; Reche, C.; Martins, V.; de Miguel, E.; Capdevila, M.; Centelles, S.; Minguillón, M. C.; Amato, F.; Alastuey, A.; Querol, X.; Gibbons, W.

2014-08-01

A high resolution air quality monitoring campaign (PM, CO2 and CO) was conducted on differently designed station platforms in the Barcelona subway system under: (a) normal forced tunnel ventilation, and (b) with daytime tunnel ventilation systems shut down. PM concentrations are highly variable (6-128 μgPM1 m-3, 16-314 μgPM3 m-3, and 33-332 μgPM10 m-3, 15-min averages) depending on ventilation conditions and station design. Narrow platforms served by single-track tunnels are heavily dependent on forced tunnel ventilation and cannot rely on the train piston effect alone to reduce platform PM concentrations. In contrast PM levels in stations with spacious double-track tunnels are not greatly affected when tunnel ventilation is switched off, offering the possibility of significant energy savings without damaging air quality. Sampling at different positions along the platform reveals considerable lateral variation, with the greatest accumulation of particulates occurring at one end of the platform. Passenger accesses can dilute PM concentrations by introducing cleaner outside air, although lateral down-platform accesses are less effective than those positioned at the train entry point. CO concentrations on the platform are very low (≤1 ppm) and probably controlled by ingress of traffic-contaminated street-level air. CO2 averages range from 371 to 569 ppm, changing during the build-up and exchange of passengers with each passing train.

Nutritional quality of food items on fast-food 'kids' menus': comparisons across countries and companies.

PubMed

Hobin, Erin; White, Christine; Li, Ye; Chiu, Maria; O'Brien, Mary Fodor; Hammond, David

2014-10-01

To compare energy (calories), total and saturated fats, and Na levels for 'kids' menu' food items offered by four leading multinational fast-food chains across five countries. A content analysis was used to create a profile of the nutritional content of food items on kids' menus available for lunch and dinner in four leading fast-food chains in Australia, Canada, New Zealand, the UK and the USA. Food items from kids' menus were included from four fast-food companies: Burger King, Kentucky Fried Chicken (KFC), McDonald's and Subway. These fast-food chains were selected because they are among the top ten largest multinational fast-food chains for sales in 2010, operate in high-income English-speaking countries, and have a specific section of their restaurant menus labelled 'kids' menus'. The results by country indicate that kids' menu foods contain less energy (fewer calories) in restaurants in the USA and lower Na in restaurants in the UK. The results across companies suggest that kids' menu foods offered at Subway restaurants are lower in total fat than food items offered at Burger King and KFC, and food items offered at KFC are lower in saturated fat than items offered at Burger King. Although the reasons for the variation in the nutritional quality of foods on kids' menus are not clear, it is likely that fast-food companies could substantially improve the nutritional quality of their kids' menu food products, translating to large gains for population health.

Consumers' estimation of calorie content at fast food restaurants: cross sectional observational study.

PubMed

Block, Jason P; Condon, Suzanne K; Kleinman, Ken; Mullen, Jewel; Linakis, Stephanie; Rifas-Shiman, Sheryl; Gillman, Matthew W

2013-05-23

To investigate estimation of calorie (energy) content of meals from fast food restaurants in adults, adolescents, and school age children. Cross sectional study of repeated visits to fast food restaurant chains. 89 fast food restaurants in four cities in New England, United States: McDonald's, Burger King, Subway, Wendy's, KFC, Dunkin' Donuts. 1877 adults and 330 school age children visiting restaurants at dinnertime (evening meal) in 2010 and 2011; 1178 adolescents visiting restaurants after school or at lunchtime in 2010 and 2011. Estimated calorie content of purchased meals. Among adults, adolescents, and school age children, the mean actual calorie content of meals was 836 calories (SD 465), 756 calories (SD 455), and 733 calories (SD 359), respectively. A calorie is equivalent to 4.18 kJ. Compared with the actual figures, participants underestimated calorie content by means of 175 calories (95% confidence interval 145 to 205), 259 calories (227 to 291), and 175 calories (108 to 242), respectively. In multivariable linear regression models, underestimation of calorie content increased substantially as the actual meal calorie content increased. Adults and adolescents eating at Subway estimated 20% and 25% lower calorie content than McDonald's diners (relative change 0.80, 95% confidence interval 0.66 to 0.96; 0.75, 0.57 to 0.99). People eating at fast food restaurants underestimate the calorie content of meals, especially large meals. Education of consumers through calorie menu labeling and other outreach efforts might reduce the large degree of underestimation.

A long-time limit for world subway networks.

PubMed

Roth, Camille; Kang, Soong Moon; Batty, Michael; Barthelemy, Marc

2012-10-07

We study the temporal evolution of the structure of the world's largest subway networks in an exploratory manner. We show that, remarkably, all these networks converge to a shape that shares similar generic features despite their geographical and economic differences. This limiting shape is made of a core with branches radiating from it. For most of these networks, the average degree of a node (station) within the core has a value of order 2.5 and the proportion of k = 2 nodes in the core is larger than 60 per cent. The number of branches scales roughly as the square root of the number of stations, the current proportion of branches represents about half of the total number of stations, and the average diameter of branches is about twice the average radial extension of the core. Spatial measures such as the number of stations at a given distance to the barycentre display a first regime which grows as r(2) followed by another regime with different exponents, and eventually saturates. These results--difficult to interpret in the framework of fractal geometry--confirm and yield a natural explanation in the geometric picture of this core and their branches: the first regime corresponds to a uniform core, while the second regime is controlled by the interstation spacing on branches. The apparent convergence towards a unique network shape in the temporal limit suggests the existence of dominant, universal mechanisms governing the evolution of these structures.

A long-time limit for world subway networks

PubMed Central

Roth, Camille; Kang, Soong Moon; Batty, Michael; Barthelemy, Marc

2012-01-01

We study the temporal evolution of the structure of the world's largest subway networks in an exploratory manner. We show that, remarkably, all these networks converge to a shape that shares similar generic features despite their geographical and economic differences. This limiting shape is made of a core with branches radiating from it. For most of these networks, the average degree of a node (station) within the core has a value of order 2.5 and the proportion of k = 2 nodes in the core is larger than 60 per cent. The number of branches scales roughly as the square root of the number of stations, the current proportion of branches represents about half of the total number of stations, and the average diameter of branches is about twice the average radial extension of the core. Spatial measures such as the number of stations at a given distance to the barycentre display a first regime which grows as r2 followed by another regime with different exponents, and eventually saturates. These results—difficult to interpret in the framework of fractal geometry—confirm and yield a natural explanation in the geometric picture of this core and their branches: the first regime corresponds to a uniform core, while the second regime is controlled by the interstation spacing on branches. The apparent convergence towards a unique network shape in the temporal limit suggests the existence of dominant, universal mechanisms governing the evolution of these structures. PMID:22593096

Navigational strategies during fast walking: a comparison between trained athletes and non-athletes.

PubMed

Gérin-Lajoie, Martin; Ronsky, Janet L; Loitz-Ramage, Barbara; Robu, Ion; Richards, Carol L; McFadyen, Bradford J

2007-10-01

Many common activities such as walking in a shopping mall, moving in a busy subway station, or even avoiding opponents during sports, all require different levels of navigational skills. Obstacle circumvention is beginning to be understood across age groups, but studying trained athletes with greater levels of motor ability will further our understanding of skillful adaptive locomotor behavior. The objective of this work was to compare navigational skills during fast walking between elite athletes (e.g. soccer, field hockey, basketball) and aged-matched non-athletes under different levels of environmental complexity in relation to obstacle configuration and visibility. The movements of eight women athletes and eight women non-athletes were measured as they walked as fast as possible through different obstacle courses in both normal and low lighting conditions. Results showed that athletes, despite similar unobstructed maximal speeds to non-athletes, had faster walking times during the navigation of all obstructed environments. It appears that athletes can process visuo-spatial information faster since both groups can make appropriate navigational decisions, but athletes can navigate through complex, novel, environments at greater speeds. Athletes' walking times were also more affected by the low lighting conditions suggesting that they normally scan the obstructed course farther ahead. This study also uses new objective measures to assess functional locomotor capacity in order to discriminate individuals according to their level of navigational ability. The evaluation paradigm and outcome measures developed may be applicable to the evaluation of skill level in athletic training and selection, as well as in gait rehabilitation following impairment.

Continuous Mapping of Tunnel Walls in a Gnss-Denied Environment

NASA Astrophysics Data System (ADS)

Chapman, Michael A.; Min, Cao; Zhang, Deijin

2016-06-01

The need for reliable systems for capturing precise detail in tunnels has increased as the number of tunnels (e.g., for cars and trucks, trains, subways, mining and other infrastructure) has increased and the age of these structures and, subsequent, deterioration has introduced structural degradations and eventual failures. Due to the hostile environments encountered in tunnels, mobile mapping systems are plagued with various problems such as loss of GNSS signals, drift of inertial measurements systems, low lighting conditions, dust and poor surface textures for feature identification and extraction. A tunnel mapping system using alternate sensors and algorithms that can deliver precise coordinates and feature attributes from surfaces along the entire tunnel path is presented. This system employs image bridging or visual odometry to estimate precise sensor positions and orientations. The fundamental concept is the use of image sequences to geometrically extend the control information in the absence of absolute positioning data sources. This is a non-trivial problem due to changes in scale, perceived resolution, image contrast and lack of salient features. The sensors employed include forward-looking high resolution digital frame cameras coupled with auxiliary light sources. In addition, a high frequency lidar system and a thermal imager are included to offer three dimensional point clouds of the tunnel walls along with thermal images for moisture detection. The mobile mapping system is equipped with an array of 16 cameras and light sources to capture the tunnel walls. Continuous images are produced using a semi-automated mosaicking process. Results of preliminary experimentation are presented to demonstrate the effectiveness of the system for the generation of seamless precise tunnel maps.

Route Type Determination Analysis

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

Brett Stone

2011-09-01

According to the 2009 National Household Travel Survey 44.4 percent of all miles travelled by Americans in 2009 (including airplanes, trains, boats, golf carts, subways, bikes, etc.) were travelled in cars. If vans, SUV's and pickup trucks are included, that level increases to 86 percent. We do a lot of travelling on the road in personal vehicles - it's important to be able to understand how we get there and how to rate the fuel economy of our trips. An essential part of this is knowing how to decide if a trip is a city or highway trip.

Critical Foundations: Protecting America’s Infrastructures. The Report of the President’s Commission on Critical Infrastructure Protection.

DTIC Science & Technology

1997-10-13

in Tokyo and bombings of the subway system in Paris, mass transit remains open and vulnerable to terrorist acts. Millions of miles of pipelines carry...Outside of "" C Risk Management Plan . Creates a Competitive Advantage , Not Considered Industry’s "• Protects Brand/ Franchise Responsibility- I ssue of...the out- set, the Commission considered expanding the scope of this sector to include food , health care and the nation’s work force as additional

Modeling the Blast Load Simulator Airblast Environment using First Principles Codes. Report 1, Blast Load Simulator Environment

DTIC Science & Technology

2016-11-01

ER D C/ G SL T R- 16 -3 1 Modeling the Blast Load Simulator Airblast Environment Using First Principles Codes Report 1, Blast Load...Simulator Airblast Environment using First Principles Codes Report 1, Blast Load Simulator Environment Gregory C. Bessette, James L. O’Daniel...evaluate several first principles codes (FPCs) for modeling airblast environments typical of those encountered in the BLS. The FPCs considered were

Communicating the promise, risks, and ethics of large-scale, open space microbiome and metagenome research.

PubMed

Shamarina, Daria; Stoyantcheva, Iana; Mason, Christopher E; Bibby, Kyle; Elhaik, Eran

2017-10-04

The public commonly associates microorganisms with pathogens. This suspicion of microorganisms is understandable, as historically microorganisms have killed more humans than any other agent while remaining largely unknown until the late seventeenth century with the works of van Leeuwenhoek and Kircher. Despite our improved understanding regarding microorganisms, the general public are apt to think of diseases rather than of the majority of harmless or beneficial species that inhabit our bodies and the built and natural environment. As long as microbiome research was confined to labs, the public's exposure to microbiology was limited. The recent launch of global microbiome surveys, such as the Earth Microbiome Project and MetaSUB (Metagenomics and Metadesign of Subways and Urban Biomes) project, has raised ethical, financial, feasibility, and sustainability concerns as to the public's level of understanding and potential reaction to the findings, which, done improperly, risk negative implications for ongoing and future investigations, but done correctly, can facilitate a new vision of "smart cities." To facilitate improved future research, we describe here the major concerns that our discussions with ethics committees, community leaders, and government officials have raised, and we expound on how to address them. We further discuss ethical considerations of microbiome surveys and provide practical recommendations for public engagement.

Multi-hole seismic modeling in 3-D space and cross-hole seismic tomography analysis for boulder detection

NASA Astrophysics Data System (ADS)

Cheng, Fei; Liu, Jiangping; Wang, Jing; Zong, Yuquan; Yu, Mingyu

2016-11-01

A boulder stone, a common geological feature in south China, is referred to the remnant of a granite body which has been unevenly weathered. Undetected boulders could adversely impact the schedule and safety of subway construction when using tunnel boring machine (TBM) method. Therefore, boulder detection has always been a key issue demanded to be solved before the construction. Nowadays, cross-hole seismic tomography is a high resolution technique capable of boulder detection, however, the method can only solve for velocity in a 2-D slice between two wells, and the size and central position of the boulder are generally difficult to be accurately obtained. In this paper, the authors conduct a multi-hole wave field simulation and characteristic analysis of a boulder model based on the 3-D elastic wave staggered-grid finite difference theory, and also a 2-D imaging analysis based on first arrival travel time. The results indicate that (1) full wave field records could be obtained from multi-hole seismic wave simulations. Simulation results describe that the seismic wave propagation pattern in cross-hole high-velocity spherical geological bodies is more detailed and can serve as a basis for the wave field analysis. (2) When a cross-hole seismic section cuts through the boulder, the proposed method provides satisfactory cross-hole tomography results; however, when the section is closely positioned to the boulder, such high-velocity object in the 3-D space would impact on the surrounding wave field. The received diffracted wave interferes with the primary wave and in consequence the picked first arrival travel time is not derived from the profile, which results in a false appearance of high-velocity geology features. Finally, the results of 2-D analysis in 3-D modeling space are comparatively analyzed with the physical model test vis-a-vis the effect of high velocity body on the seismic tomographic measurements.

The single-species metagenome: subtyping Staphylococcus aureus core genome sequences from shotgun metagenomic data

PubMed Central

Li, Ben; Petit III, Robert A.; Qin, Zhaohui S.; Darrow, Lyndsey

2016-01-01

In this study we developed a genome-based method for detecting Staphylococcus aureus subtypes from metagenome shotgun sequence data. We used a binomial mixture model and the coverage counts at >100,000 known S. aureus SNP (single nucleotide polymorphism) sites derived from prior comparative genomic analysis to estimate the proportion of 40 subtypes in metagenome samples. We were able to obtain >87% sensitivity and >94% specificity at 0.025X coverage for S. aureus. We found that 321 and 149 metagenome samples from the Human Microbiome Project and metaSUB analysis of the New York City subway, respectively, contained S. aureus at genome coverage >0.025. In both projects, CC8 and CC30 were the most common S. aureus clonal complexes encountered. We found evidence that the subtype composition at different body sites of the same individual were more similar than random sampling and more limited evidence that certain body sites were enriched for particular subtypes. One surprising finding was the apparent high frequency of CC398, a lineage often associated with livestock, in samples from the tongue dorsum. Epidemiologic analysis of the HMP subject population suggested that high BMI (body mass index) and health insurance are possibly associated with S. aureus carriage but there was limited power to identify factors linked to carriage of even the most common subtype. In the NYC subway data, we found a small signal of geographic distance affecting subtype clustering but other unknown factors influence taxonomic distribution of the species around the city. PMID:27781166

Mess in mass transit: though demand is up, the service is down

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

Not Available

1979-07-16

Mass transit systems (bus and rail), in poor mechanical and physical condition, are facing an economic crisis. Most industries that had been constructing new rail or bus equipment have now quit production completely or nearly so. San Diego is buying trolleys for its 16-mile line to the Mexican border, on which construction will begin in late 1979, from a West German supplier. The background of how the US got into this situation is reviewed. American's love affair with the automobile put the transit systems in financial trouble with poor ridership, and now the companies are afraid to reconstruct, thinking perhapsmore » Americans will revert to the automobile if gasoline again becomes plentiful. As the US attempts to remedy the transit situation, there should be a burden sharing between local and Federal governments. Local transit authorities should carry the operating costs, but even if they are heavily traveled, fares meet only 48% of operating costs. Therefore, communities will have to find ways to raise money in order to keep the systems running. The Carter Administration did not seize on mass transit as a means of conserving gasoline, but President Carter did say that part of the windfall tax on oil companies would be set aside for mass transport. But some progress is noted: Baltimore is digging its first subway; Buffalo began construction of a 6.5-mile subway and elevated-transit system; and Atlanta put into operation the first 6.7-mile segment of MARTA. Improvisions in many cities are noted, such as, leasing commercial buses and pressing school buses into operation. (MCW)« less

Consumers’ estimation of calorie content at fast food restaurants: cross sectional observational study

PubMed Central

Condon, Suzanne K; Kleinman, Ken; Mullen, Jewel; Linakis, Stephanie; Rifas-Shiman, Sheryl; Gillman, Matthew W

2013-01-01

Objective To investigate estimation of calorie (energy) content of meals from fast food restaurants in adults, adolescents, and school age children. Design Cross sectional study of repeated visits to fast food restaurant chains. Setting 89 fast food restaurants in four cities in New England, United States: McDonald’s, Burger King, Subway, Wendy’s, KFC, Dunkin’ Donuts. Participants 1877 adults and 330 school age children visiting restaurants at dinnertime (evening meal) in 2010 and 2011; 1178 adolescents visiting restaurants after school or at lunchtime in 2010 and 2011. Main outcome measure Estimated calorie content of purchased meals. Results Among adults, adolescents, and school age children, the mean actual calorie content of meals was 836 calories (SD 465), 756 calories (SD 455), and 733 calories (SD 359), respectively. A calorie is equivalent to 4.18 kJ. Compared with the actual figures, participants underestimated calorie content by means of 175 calories (95% confidence interval 145 to 205), 259 calories (227 to 291), and 175 calories (108 to 242), respectively. In multivariable linear regression models, underestimation of calorie content increased substantially as the actual meal calorie content increased. Adults and adolescents eating at Subway estimated 20% and 25% lower calorie content than McDonald’s diners (relative change 0.80, 95% confidence interval 0.66 to 0.96; 0.75, 0.57 to 0.99). Conclusions People eating at fast food restaurants underestimate the calorie content of meals, especially large meals. Education of consumers through calorie menu labeling and other outreach efforts might reduce the large degree of underestimation. PMID:23704170

Six-year trend in active commuting to school in Spanish adolescents. The AVENA and AFINOS Studies.

PubMed

Chillón, Palma; Martínez-Gómez, David; Ortega, Francisco B; Pérez-López, Isaac J; Díaz, Ligia E; Veses, Ana M; Veiga, Oscar L; Marcos, Ascensión; Delgado-Fernández, Manuel

2013-12-01

Promoting daily routine activities, such as active commuting to school, may have important health implications for young people. The aim of the study was to examine the secular trend of active commuting to school in Spanish adolescents over a 6-year period (2001-2002 to 2006-2007). We also examined several factors that might explain this trend. Data comes from two separate cross-sectional studies, both representatives from the city of Madrid (Spain): AVENA and AFINOS studies. These took place in 2001-2002 and 2006-2007 and included 415 (198 girls) and 891 (448 girls) adolescents aged 13-17, respectively. Commuting to school was assessed using a standardized question about their habitual mode of transportation to school: walking, cycling, bus/subway, car, or motorcycle. Chi-square and binary logistic regression were used. Percentage of active commuting girls decreased significantly from 61 % to 48 % (p = 0.002) from 2001-2002 to 2006-2007. Walking declined from 61 % to 46 % and the use of bus/subway increased from 25 % to 37 % in girls. Girls belonging to average/small families had lower odds of being active commuters than girls of large families (OR, 95 % CI: 0.69, 0.48 to 0.98). There were no significant differences in mode of commuting to school for boys (p = 0.269). Spanish adolescent girls in 2007-2008 had lower levels of active commuting to school, mainly walking, than their counterparts 6 years before. Belonging to a large family was related with higher active commuting in girls.

Hydrogeologic controls on ground-water discharge to the Washington METRO subway tunnel near the Medical Center station and Crossover, Montgomery County, Maryland

USGS Publications Warehouse

Greene, Earl A.; Shapiro, Allen M.; LaMotte, Andrew E.

2004-01-01

Excessive water intrusion has been observed inside several of the Washington Metropolitan Area Transit Authority subway tunnels, with the worst leakage occurring along the Red Line tunnels and stations north of Dupont Circle in Washington, D.C. These tunnels were constructed in bedrock that contains permeable (water-bearing) joints and fractures. Excessive water leakage through the walls and water inside the underground facilities has damaged mechanical and electrical components in the tunnel, and has escalated the deterioration rate of the rail system. The U.S. Geological Survey and the Washington Metropolitan Area Transit Authority have worked cooperatively on a study from 200003 to describe and quantify the factors controlling ground-water flow into the Red Line subway tunnel near the Medical Center Station and Crossover in Montgomery County, Maryland. The Red Line near the Medical Center Station and Crossover passes through or beneath the gneissic Sykesville Formation and the biotite-hornblende tonalite member of the Georgetown Intrusive Suite, both of which contain numerous fractures. The mapped foliation and joints of the Sykesville Formation in the vicinity of the Medical Center Station and Crossover are generally orientated north-south. Fractures in the Sykesville Formation in outcrops appear to be poorly connected. In the biotite-hornblende tonalite member of the Georgetown Intrusive Suite, the general orientation of the mapped foliation and joints is east-west. In contrast to the fractures in the Sykesville Formation, the fractures in the Georgetown Intrusive Suite in outcrops appear to be more numerous and have a greater degree of connectivity. Fractures intersecting four bedrock wells near the Medical Center Station and Crossover that were drilled into the biotite-hornblende tonalite member of the Georgetown Intrusive Suite show an east-west orientation matching the foliation and joints shown on geologic maps. The excessive water intrusion at the Medical Center Station and Crossover could be the result of its location within the Georgetown Intrusive Suite. The abrupt changes in the mapped directions of ground-water flow based on the hydraulic heads at the contact between the Sykesville Formation and biotite-hornblende tonalite member of the Georgetown Intrusive Suite could also be the result of the change in fracturing between these two lithologies. Saprolite, a residual of soft, red/brown to gray clay from decomposed crystalline rock, overlies the bedrock and varies from about 20 to 55 feet thick, depending on location. On the basis of a slug test conducted in the lower part of the saprolite near the Medical Center Station and Crossover, transmissivity and storativity of the saprolite were estimated to be 10 feet squared per day and 10-6 , respectively. The transmissivity of fractures intersecting bedrock boreholes drilled in the biotite-hornblende tonalite member of the Georgetown Intrusive Suite varies over five orders of magnitude, from a maximum of approximately 10 feet squared per day to the detection limit of the in situ testing apparatus, which is approximately 10-4 feet squared per day. In general, the transmissivity of fractures intersecting the boreholes increases with depth. The low transmissivity of bedrock fractures in close proximity to the saprolite is likely to be caused by the fractures being filled with byproducts of rock weathering, resulting in reduced permeability. 2 Hydrogeologic Controls on Ground-Water Discharge to the Washington METRO Subway Tunnel The bulk transmissivity of the bedrock aquifer is approximately 3.7 feet squared per day, as determined from an aquifer test conducted by pumping a 240-foot-deep borehole and monitoring the drawdown over 3 days in the pumped borehole and several observation boreholes. In general, the hydraulic head decreases with depth in bedrock boreholes, indicating the potential for downward ground-water flow. Based on hydraulic head values mea

Chemical Characterisation of the Coarse and Fine Particulate Matter in the Environment of an Underground Railway System: Cytotoxic Effects and Oxidative Stress—A Preliminary Study

PubMed Central

Spagnolo, Anna Maria; Ottria, Gianluca; Perdelli, Fernanda; Cristina, Maria Luisa

2015-01-01

Background: Exposure to the particulate matter produced in underground railway systems is arousing increasing scientific interest because of its health effects. The aim of our study was to evaluate the airborne concentrations of PM10 and three sub-fractions of PM2.5 in an underground railway system environment in proximity to platforms and in underground commercial areas within the system, and to compare these with the outdoor airborne concentrations. We also evaluated the metal components, the cytotoxic properties of the various fractions of particulate matter (PM) and their capacity to induce oxidative stress. Method: We collected the coarse fraction (5–10 µm) and the fine fractions (1–2.5 µm; 0.5–1 µm; 0.25–0.5 µm). Chemical characterisation was determined by means of spectrometry. Cytotoxicity and oxidative stress were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Reactive Oxygen Species (ROS) assessment. Results: The concentrations of both PM10 and PM2.5 proved to be similar at the three sampling sites. Iron and other transition metals displayed a greater concentration at the subway platform than at the other two sites. The 2.5–10 µm and 1–2.5 µm fractions of PM from all three sampling sites determined a greater increase in ROS; the intensity of oxidative stress progressively declined as particle diameter diminished. Moreover, ROS concentrations were correlated with the concentrations of some transition metals, namely Mn, Cr, Ti, Fe, Cu, Zn, Ni and Mo. All particulate matter fractions displayed lower or similar ROS values between platform level and the outdoor air. Conclusions: The present study revealed that the underground railway environment at platform level, although containing higher concentrations of some particularly reactive metallic species, did not display higher cytotoxicity and oxidative stress levels than the outdoor air. PMID:25872016

Chemical characterisation of the coarse and fine particulate matter in the environment of an underground railway system: cytotoxic effects and oxidative stress-a preliminary study.

PubMed

Spagnolo, Anna Maria; Ottria, Gianluca; Perdelli, Fernanda; Cristina, Maria Luisa

2015-04-13

Exposure to the particulate matter produced in underground railway systems is arousing increasing scientific interest because of its health effects. The aim of our study was to evaluate the airborne concentrations of PM10 and three sub-fractions of PM2.5 in an underground railway system environment in proximity to platforms and in underground commercial areas within the system, and to compare these with the outdoor airborne concentrations. We also evaluated the metal components, the cytotoxic properties of the various fractions of particulate matter (PM) and their capacity to induce oxidative stress. We collected the coarse fraction (5-10 µm) and the fine fractions (1-2.5 µm; 0.5-1 µm; 0.25-0.5 µm). Chemical characterisation was determined by means of spectrometry. Cytotoxicity and oxidative stress were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Reactive Oxygen Species (ROS) assessment. The concentrations of both PM10 and PM2.5 proved to be similar at the three sampling sites. Iron and other transition metals displayed a greater concentration at the subway platform than at the other two sites. The 2.5-10 µm and 1-2.5 µm fractions of PM from all three sampling sites determined a greater increase in ROS; the intensity of oxidative stress progressively declined as particle diameter diminished. Moreover, ROS concentrations were correlated with the concentrations of some transition metals, namely Mn, Cr, Ti, Fe, Cu, Zn, Ni and Mo. All particulate matter fractions displayed lower or similar ROS values between platform level and the outdoor air. The present study revealed that the underground railway environment at platform level, although containing higher concentrations of some particularly reactive metallic species, did not display higher cytotoxicity and oxidative stress levels than the outdoor air.

The simulated clinical environment: Cognitive and emotional impact among undergraduates.

PubMed

Tremblay, Marie-Laurence; Lafleur, Alexandre; Leppink, Jimmie; Dolmans, Diana H J M

2017-02-01

Simulated clinical immersion (SCI) is used in undergraduate healthcare programs to expose the learner to real-life situations in authentic simulated clinical environments. For novices, the environment in which the simulation occurs can be distracting and stressful, hence potentially compromising learning. This study aims to determine whether SCI (with environment) imposes greater extraneous cognitive load and stress on undergraduate pharmacy students than simulated patients (SP) (without environment). It also aims to explore how features of the simulated environment influence students' perception of learning. In this mixed-methods study, 143 undergraduate pharmacy students experienced both SCI and SP in a crossover design. After the simulations, participants rated their cognitive load and emotions. Thirty-five students met in focus groups to explore their perception of learning in simulation. Intrinsic and extraneous cognitive load and stress scores in SCI were significantly but modestly higher compared to SP. Qualitative findings reveal that the physical environment in SCI generated more stress and affected students? focus. In SP, students concentrated on clinical reasoning. SCI stimulated a focus on data collection but impeded in-depth problem solving processes. The physical environment in simulation influences what and how students learn. SCI was reported as more cognitively demanding than SP. Our findings emphasize the need for the development of adapted instructional design guidelines in simulation for novices.

Integrated Clinical Training for Space Flight Using a High-Fidelity Patient Simulator in a Simulated Microgravity Environment

NASA Technical Reports Server (NTRS)

Hurst, Victor; Doerr, Harold K.; Polk, J. D.; Schmid, Josef; Parazynksi, Scott; Kelly, Scott

2007-01-01

This viewgraph presentation reviews the use of telemedicine in a simulated microgravity environment using a patient simulator. For decades, telemedicine techniques have been used in terrestrial environments by many cohorts with varied clinical experience. The success of these techniques has been recently expanded to include microgravity environments aboard the International Space Station (ISS). In order to investigate how an astronaut crew medical officer will execute medical tasks in a microgravity environment, while being remotely guided by a flight surgeon, the Medical Operation Support Team (MOST) used the simulated microgravity environment provided aboard DC-9 aircraft teams of crew medical officers, and remote flight surgeons performed several tasks on a patient simulator.

Particulate matter concentration and chemical composition in the metro system of Rome, Italy.

PubMed

Perrino, C; Marcovecchio, F; Tofful, L; Canepari, S

2015-06-01

Air quality at the main station of the metro system of Rome (Termini hub) has been characterized by the point of view of particulate matter (PM) concentration and chemical composition. Indoor air in different environments (underground train platform and shopping center, metro carriages with and without air conditioning system) has been studied and compared with outdoor air at a nearby urban site. Air quality at the railway station, located outdoor at surface level, has been also considered for comparison. PM chemical characterization included ions, elemental carbon, organic carbon, macro-elements, and the bio-accessible and residual fractions of micro- and trace elements. Train platform and carriages without air conditioning resulted to be the most polluted environments, with indoor/outdoor ratio up to two orders of magnitude for many components. PM mass concentration was determined on filter membranes by the gravimetric procedure as well as from the optical particle counter (OPC) number concentration measurements. The OPC results, taken with the original calibration factor, were below 40 % of the value obtained by the gravimetric measurements. Only a chemical and morphological characterization of the collected dust could lead to a reconciliation of the results yielded by the two methods. Macro-components were used to estimate the strength of the main macro-sources. The most significant contribution is confirmed to derive from wheels, rails, and brakes abrasion; from soil re-suspension (over 50 % at the subway platform); and from organics (about 25 %). The increase in the concentration of elements was mostly due to the residual fraction, but also the bio-accessible fraction showed a remarkable enrichment, particularly in the case of Ba, Zn, Cd, and Ni.

An intelligent processing environment for real-time simulation

NASA Technical Reports Server (NTRS)

Carroll, Chester C.; Wells, Buren Earl, Jr.

1988-01-01

The development of a highly efficient and thus truly intelligent processing environment for real-time general purpose simulation of continuous systems is described. Such an environment can be created by mapping the simulation process directly onto the University of Alamba's OPERA architecture. To facilitate this effort, the field of continuous simulation is explored, highlighting areas in which efficiency can be improved. Areas in which parallel processing can be applied are also identified, and several general OPERA type hardware configurations that support improved simulation are investigated. Three direct execution parallel processing environments are introduced, each of which greatly improves efficiency by exploiting distinct areas of the simulation process. These suggested environments are candidate architectures around which a highly intelligent real-time simulation configuration can be developed.

Protection of Buried Pipe under Repeated Loading by Geocell Reinforcement

NASA Astrophysics Data System (ADS)

Khalaj, Omid; Joz Darabi, N.; Moghaddas Tafreshi, S. N.; Mašek, Bohuslav

2017-12-01

With increase in cities’ population and development of urbane life, passing buried pipelines near ground’s surface is inevitable in urban areas, roads, subways and highways. This paper presents the results of three-dimensional full scale model tests on high-density polyethylene (HDPE) pipe with diameter of 250 mm in geocell reinforced soil, subjected to repeated loading to simulate the vehicle loads. The effect of geocell’s pocket size (55*55 mm and 110*110 mm) and embedment depth of buried pipe (1.5 and 2 times pipe diameter) in improving the behaviour of buried pipes was investigated. The geocell’s height of 100 mm was used in all tests. The repeated load of 800 kPa was applied on circular loading plate with diameter of 250 mm. The results show that the pipe displacement, soil surface settlement and transferred pressure on the pipe’s crown has been influenced significantly upon the use of geocells. For example, the vertical diametric strain (VDS) and soil surface settlement (SSS), in a way that using a geocell with pocket size of 110*110 mm reduces by 27% and 43%, respectively, compared with the unreinforced one. Meanwhile, by increasing buried depth of pipe from 1.5D to 2D, the use of geocell of 110*110 mm delivers about 50% reduction in SSS and VDS, compared with the unreinforced soil.

Unnatural deaths in Shanghai from 2000 to 2009: a retrospective study of forensic autopsy cases at the Shanghai Public Security Bureau.

PubMed

He, Meng; Fang, You-Xin; Lin, Jun-Yi; Ma, Kai-Jun; Li, Bei-Xu

2015-01-01

Shanghai is the most developed city in China and has a soaring population. This study uses forensic epidemiology to determine the relationship between unnatural deaths and the development in Shanghai, based on recently released forensic autopsy cases from the 2000s at the Shanghai Public Security Bureau (SPSB). There were 5425 accidental deaths, 2696 homicides, 429 suicides, 186 natural deaths, and 1399 deaths of undetermined cause. There was a male-to-female ratio of 2.02:1, and the average age was 40.9±18.7 years. Traffic accidents (84.2%) were the number one cause of accidental deaths, which decreased during the study period. Sharp force injury (50.6%) was the leading cause of homicides, different from Western countries, where firearms are the leading cause. Hanging (24.5%) was the leading cause of suicides, whereas drug and chemical intoxication was the leading cause in the previous decade; pesticide ingestion decreased in the 2000s. In addition to traffic accidents, manual strangulation was the leading cause of death in childhood fatalities. Children under age 2 were vulnerable to homicides. In the 2000s, there were a large number of drug overdoses, and illegal medical practices and subway-related deaths first appeared in Shanghai. A new type of terrorist attack that involved injecting people with syringes in public places was reflected in the SPSB archives. The forensic epidemiology and changes in unnatural deaths in this decade reflected their relationship with the law, policy and changes in Shanghai. Illegal medical practices, subway-related deaths and terrorist attacks were closely related to the development in Shanghai. Identifying the risks of unnatural deaths will improve public health.

Optimizing a desirable fare structure for a bus-subway corridor

PubMed Central

Liu, Bing-Zheng; Ge, Ying-En; Cao, Kai; Jiang, Xi; Meng, Lingyun; Liu, Ding; Gao, Yunfeng

2017-01-01

This paper aims to optimize a desirable fare structure for the public transit service along a bus-subway corridor with the consideration of those factors related to equity in trip, including travel distance and comfort level. The travel distance factor is represented by the distance-based fare strategy, which is an existing differential strategy. The comfort level one is considered in the area-based fare strategy which is a new differential strategy defined in this paper. Both factors are referred to by the combined fare strategy which is composed of distance-based and area-based fare strategies. The flat fare strategy is applied to determine a reference level of social welfare and obtain the general passenger flow along transit lines, which is used to divide areas or zones along the corridor. This problem is formulated as a bi-level program, of which the upper level maximizes the social welfare and the lower level capturing traveler choice behavior is a variable-demand stochastic user equilibrium assignment model. A genetic algorithm is applied to solve the bi-level program while the method of successive averages is adopted to solve the lower-level model. A series of numerical experiments are carried out to illustrate the performance of the models and solution methods. Numerical results indicate that all three differential fare strategies play a better role in enhancing the social welfare than the flat fare strategy and that the fare structure under the combined fare strategy generates the highest social welfare and the largest resulting passenger demand, which implies that the more equity factors a differential fare strategy involves the more desirable fare structure the strategy has. PMID:28981508

Unnatural Deaths in Shanghai from 2000 to 2009: A Retrospective Study of Forensic Autopsy Cases at the Shanghai Public Security Bureau

PubMed Central

Lin, Jun-Yi; Ma, Kai-Jun; Li, Bei-Xu

2015-01-01

Shanghai is the most developed city in China and has a soaring population. This study uses forensic epidemiology to determine the relationship between unnatural deaths and the development in Shanghai, based on recently released forensic autopsy cases from the 2000s at the Shanghai Public Security Bureau (SPSB). There were 5425 accidental deaths, 2696 homicides, 429 suicides, 186 natural deaths, and 1399 deaths of undetermined cause. There was a male-to-female ratio of 2.02:1, and the average age was 40.9±18.7 years. Traffic accidents (84.2%) were the number one cause of accidental deaths, which decreased during the study period. Sharp force injury (50.6%) was the leading cause of homicides, different from Western countries, where firearms are the leading cause. Hanging (24.5%) was the leading cause of suicides, whereas drug and chemical intoxication was the leading cause in the previous decade; pesticide ingestion decreased in the 2000s. In addition to traffic accidents, manual strangulation was the leading cause of death in childhood fatalities. Children under age 2 were vulnerable to homicides. In the 2000s, there were a large number of drug overdoses, and illegal medical practices and subway-related deaths first appeared in Shanghai. A new type of terrorist attack that involved injecting people with syringes in public places was reflected in the SPSB archives. The forensic epidemiology and changes in unnatural deaths in this decade reflected their relationship with the law, policy and changes in Shanghai. Illegal medical practices, subway-related deaths and terrorist attacks were closely related to the development in Shanghai. Identifying the risks of unnatural deaths will improve public health. PMID:26110435

Purchase rates and energy content of nutritionally promoted and traditional fast foods purchased at lunchtime in Australia - a pilot study.

PubMed

Atkinson, Louise F; Palmer, Michelle A

2012-03-01

Nutritionally promoted foods are now available at fast-food establishments. Little is known about their popularity, who is purchasing them, or their impact on dietary intake. Our study aimed to determine: how often nutritionally promoted fast foods were purchased; the demographic characteristics of people purchasing these foods; and if purchasing these foods resulted in reduced energy, and increased vegetable, content of lunches compared with those who purchased traditional fast foods. A survey collecting lunchtime fast-food purchases and demographic details was administered over two months. Nutritionally promoted products included the McDonalds' 'Heart Foundation Tick Approved' range and Subway's 'Six grams of fat or less' range. Energy and vegetable contents were estimated using information from fast-food companies' websites. Differences in demographics, energy and vegetable contents between individuals purchasing nutritionally promoted and traditional lunches were assessed using χ2 and t tests. Queensland, Australia. Lunchtime diners aged over 16 years at Subway and McDonalds. Surveys were collected from 927 respondents (58 % male, median age 25 (range 16-84) years; 73 % response rate). Only 3 % (n 24/910) of respondents who ordered a main option had purchased a nutritionally promoted item. Purchasers of nutritionally promoted foods were ∼13 years older, predominantly female (79 %), and more often reported involvement in a health-related profession (29 % v. 11 %) than purchasers of traditional foods (P < 0·05). Purchasers of nutritionally promoted foods ordered 1·5 fewer megajoules and 0·6 more vegetable servings than purchasers of traditional foods (P < 0·05). Nutritionally promoted fast foods may reduce lunchtime energy content, however these foods were infrequently chosen.

Effects of commuting mode on air pollution exposure and cardiovascular health among young adults in Taipei, Taiwan.

PubMed

Liu, Wen-Te; Ma, Chih-Ming; Liu, I-Jung; Han, Bor-Cheng; Chuang, Hsiao-Chi; Chuang, Kai-Jen

2015-05-01

The association between traffic-related air pollution and adverse cardiovascular effects has been well documented; however, little is known about whether different commuting modes can modify the effects of air pollution on the cardiovascular system in human subjects in urban areas with heavy traffic. We recruited 120 young, healthy subjects in Taipei, Taiwan. Each participant was classified with different commuting modes according to his/her own commuting style. Three repeated measurements of heart rate variability (HRV) indices {standard deviation of NN intervals (SDNN) and the square root of the mean of the sum of the squares of differences between adjacent NN intervals (r-MSSD)}, particulate matter with an aerodynamic diameter ≤ 2.5 μm (PM2.5), temperature, humidity and noise level were conducted for each subject during 1-h morning commutes (0900-1000 h) in four different commuting modes, including an electrically powered subway, a gas-powered bus, a gasoline-powered car, and walking. Linear mixed-effects models were used to investigate the association of PM2.5 with HRV indices. The results showed that decreases in the HRV indices were associated with increased levels of PM2.5. The personal exposure levels to PM2.5 were the highest in the walking mode. The effects of PM2.5 on cardiovascular endpoints were the lowest in the subway mode compared to the effects in the walking mode. The participants in the car and bus modes had reduced effects on their cardiovascular endpoints compared to the participants in the walking mode. We concluded that traffic-related PM2.5 is associated with autonomic alteration. Commuting modes can modify the effects of PM2.5 on HRV indices among young, healthy subjects. Copyright © 2015 Elsevier GmbH. All rights reserved.

Experimental validation of a numerical model for subway induced vibrations

NASA Astrophysics Data System (ADS)

Gupta, S.; Degrande, G.; Lombaert, G.

2009-04-01

This paper presents the experimental validation of a coupled periodic finite element-boundary element model for the prediction of subway induced vibrations. The model fully accounts for the dynamic interaction between the train, the track, the tunnel and the soil. The periodicity or invariance of the tunnel and the soil in the longitudinal direction is exploited using the Floquet transformation, which allows for an efficient formulation in the frequency-wavenumber domain. A general analytical formulation is used to compute the response of three-dimensional invariant or periodic media that are excited by moving loads. The numerical model is validated by means of several experiments that have been performed at a site in Regent's Park on the Bakerloo line of London Underground. Vibration measurements have been performed on the axle boxes of the train, on the rail, the tunnel invert and the tunnel wall, and in the free field, both at the surface and at a depth of 15 m. Prior to these vibration measurements, the dynamic soil characteristics and the track characteristics have been determined. The Bakerloo line tunnel of London Underground has been modelled using the coupled periodic finite element-boundary element approach and free field vibrations due to the passage of a train at different speeds have been predicted and compared to the measurements. The correspondence between the predicted and measured response in the tunnel is reasonably good, although some differences are observed in the free field. The discrepancies are explained on the basis of various uncertainties involved in the problem. The variation in the response with train speed is similar for the measurements as well as the predictions. This study demonstrates the applicability of the coupled periodic finite element-boundary element model to make realistic predictions of the vibrations from underground railways.

Optimizing a desirable fare structure for a bus-subway corridor.

PubMed

Liu, Bing-Zheng; Ge, Ying-En; Cao, Kai; Jiang, Xi; Meng, Lingyun; Liu, Ding; Gao, Yunfeng

2017-01-01

This paper aims to optimize a desirable fare structure for the public transit service along a bus-subway corridor with the consideration of those factors related to equity in trip, including travel distance and comfort level. The travel distance factor is represented by the distance-based fare strategy, which is an existing differential strategy. The comfort level one is considered in the area-based fare strategy which is a new differential strategy defined in this paper. Both factors are referred to by the combined fare strategy which is composed of distance-based and area-based fare strategies. The flat fare strategy is applied to determine a reference level of social welfare and obtain the general passenger flow along transit lines, which is used to divide areas or zones along the corridor. This problem is formulated as a bi-level program, of which the upper level maximizes the social welfare and the lower level capturing traveler choice behavior is a variable-demand stochastic user equilibrium assignment model. A genetic algorithm is applied to solve the bi-level program while the method of successive averages is adopted to solve the lower-level model. A series of numerical experiments are carried out to illustrate the performance of the models and solution methods. Numerical results indicate that all three differential fare strategies play a better role in enhancing the social welfare than the flat fare strategy and that the fare structure under the combined fare strategy generates the highest social welfare and the largest resulting passenger demand, which implies that the more equity factors a differential fare strategy involves the more desirable fare structure the strategy has.

Cybersickness and Anxiety During Simulated Motion: Implications for VRET.

PubMed

Bruck, Susan; Watters, Paul

2009-01-01

Some clinicians have suggested using virtual reality environments to deliver psychological interventions to treat anxiety disorders. However, given a significant body of work on cybersickness symptoms which may arise in virtual environments - especially those involving simulated motion - we tested (a) whether being exposed to a virtual reality environment alone causes anxiety to increase, and (b) whether exposure to simulated motion in a virtual reality environment increases anxiety. Using a repeated measures design, we used Kim's Anxiety Scale questionnaire to compare baseline anxiety, anxiety after virtual environment exposure, and anxiety after simulated motion. While there was no significant effect on anxiety for being in a virtual environment with no simulated motion, the introduction of simulated motion caused anxiety to significantly increase, but not to a severe or extreme level. The implications of this work for virtual reality exposure therapy (VRET) are discussed.

A Comparison of Students' Conceptual Understanding of Electric Circuits in Simulation Only and Simulation-Laboratory Contexts

ERIC Educational Resources Information Center

Jaakkola, Tomi; Nurmi, Sami; Veermans, Koen

2011-01-01

The aim of this experimental study was to compare learning outcomes of students using a simulation alone (simulation environment) with outcomes of those using a simulation in parallel with real circuits (combination environment) in the domain of electricity, and to explore how learning outcomes in these environments are mediated by implicit (only…

Electrospun Magnetic Nanoparticle-Decorated Nanofiber Filter and Its Applications to High-Efficiency Air Filtration.

PubMed

Kim, Juyoung; Chan Hong, Seung; Bae, Gwi Nam; Jung, Jae Hee

2017-10-17

Filtration technology has been widely studied due to concerns about exposure to airborne dust, including metal oxide nanoparticles, which cause serious health problems. The aim of these studies has been to develop mechanisms for the continuous and efficient removal of metal oxide dusts. In this study, we introduce a novel air filtration system based on the magnetic attraction force. The filtration system is composed of a magnetic nanoparticle (MNP)-decorated nanofiber (MNP-NF) filter. Using a simple electrospinning system, we fabricated continuous and smooth electrospun nanofibers with evenly distributed Fe 3 O 4 MNPs. Our electrospun MNP-NF filter exhibited high particle collection efficiency (∼97% at 300 nm particle size) compared to the control filter (w/o MNPs, ∼ 68%), with a ∼ 64% lower pressure drop (∼17 Pa) than the control filter (∼27 Pa). Finally, the filter quality factors of the MNP-NF filter were 4.7 and 11.9 times larger than those of the control filter and the conventional high-efficiency particulate air filters (>99% and ∼269 Pa), respectively. Furthermore, we successfully performed a field test of our MNP-NF filter using dust from a subway station tunnel. This work suggests that our novel MNP-NF filter can be used to facilitate effective protection against hazardous metal oxide dust in real environments.

Pathways for the Oxidation of Sarin in Urban Atmospheres

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

Gerald E. Streit; James E. Bossert; Jeffrey S. Gaffney

1998-11-01

Terrorists have threatened and carried out chemicalhiological agent attacks on targets in major cities. The nerve agent sarin figured prominently in one well-publicized incident. Vapors disseminating from open containers in a Tokyo subway caused thousands of casualties. High-resolution tracer transport modeling of agent dispersion is at hand and will be enhanced by data on reactions with components of the urban atmosphere. As a sample of the level of complexity currently attainable, we elaborate the mechanisms by which sarin can decompose in polluted air. A release scenario is outlined involving the passage of a gas-phase agent through a city locale inmore » the daytime. The atmospheric chemistry database on related organophosphorus pesticides is mined for rate and product information. The hydroxyl,radical and fine-mode particles are identified as major reactants. A review of urban air chernistry/rnicrophysics generates concentration tables for major oxidant and aerosol types in both clean and dirty environments. Organic structure-reactivity relationships yield an upper limit of 10-1' cm3 molecule-' S-* for hydrogen abstraction by hydroxyl. The associated midday loss time scale could be as little as one hour. Product distributions are difficult to define but may include nontoxic organic oxygenates, inorganic phosphorus acids, sarin-like aldehydes, and nitrates preserving cholinergic capabilities. Agent molecules will contact aerosol surfaces in on the order of minutes, with hydrolysis and side-chain oxidation as likely reaction channels.« less

Climate Science for Decision-Making in the New York Metropolitan Region. Chapter 3

NASA Technical Reports Server (NTRS)

Horton, Radley; Rosenzweig, Cynthia; Solecki, William; Bader, Daniel; Sohl, Linda

2016-01-01

New York City is one of the world's most vulnerable cities to coastal flooding, due to a high concentration of population and assets near a coastline exposed to warm-season tropical storms and cold -season Nor'easter storms. Among U.S. cities, New York City is second only to New Orleans in population living less than 4 ft above the local high tide. By the 2050s, average annual losses due to coastal flooding alone could exceed $2 billion for the combined New York City-Newark region. Perhaps the most iconic example of a vulnerable New York City asset is the financial district located at the southern tip of Manhattan, however low-lying coastal assets include the full complement of major highways, subways and tunnels, hospitals, schools, wastewater treatment plants, food distribution centers, and people's homes. Given the magnitude of the assets at risk, a compelling case can be made that long-term adaptation makes economic sense for New York City. Given New York's access to economic, human, and technological resources for resilience measures, the City may be able to achieve this resilience. The city's political environment-New York City is a place where climate science is generally not a partisan issue-and the city's experience with uncertainty and overall risk framing (e.g., financing of bond issues for multi-billion dollar infrastructure with multidecade expected lifetimes), encourage climate risk framing.

Full immersion simulation: validation of a distributed simulation environment for technical and non-technical skills training in Urology.

PubMed

Brewin, James; Tang, Jessica; Dasgupta, Prokar; Khan, Muhammad S; Ahmed, Kamran; Bello, Fernando; Kneebone, Roger; Jaye, Peter

2015-07-01

To evaluate the face, content and construct validity of the distributed simulation (DS) environment for technical and non-technical skills training in endourology. To evaluate the educational impact of DS for urology training. DS offers a portable, low-cost simulated operating room environment that can be set up in any open space. A prospective mixed methods design using established validation methodology was conducted in this simulated environment with 10 experienced and 10 trainee urologists. All participants performed a simulated prostate resection in the DS environment. Outcome measures included surveys to evaluate the DS, as well as comparative analyses of experienced and trainee urologist's performance using real-time and 'blinded' video analysis and validated performance metrics. Non-parametric statistical methods were used to compare differences between groups. The DS environment demonstrated face, content and construct validity for both non-technical and technical skills. Kirkpatrick level 1 evidence for the educational impact of the DS environment was shown. Further studies are needed to evaluate the effect of simulated operating room training on real operating room performance. This study has shown the validity of the DS environment for non-technical, as well as technical skills training. DS-based simulation appears to be a valuable addition to traditional classroom-based simulation training. © 2014 The Authors BJU International © 2014 BJU International Published by John Wiley & Sons Ltd.

A comparison of the accuracy of intraoral scanners using an intraoral environment simulator.

PubMed

Park, Hye-Nan; Lim, Young-Jun; Yi, Won-Jin; Han, Jung-Suk; Lee, Seung-Pyo

2018-02-01

The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. The differences in intraoral environments were not statistically significant ( P >.05). Between intraoral scanners, statistically significant differences ( P <.05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future.

Low-smoke, halogenfree ship-offshore/onshore cables with improved flame retardance and fire resistance

NASA Astrophysics Data System (ADS)

Pedersen, J. R.; Holte, T. A.; Johansen, E.

Cables with improved fire resistance and flame retardance have been developed. They will continue to function at least 3 hours even at temperatures up to 1000 C and do not propagate fire when tested according to IEC 332 part 3 1982, category A. Made with halogenfree materials they give off no corrosive gases and very little visible smoke in cases of fire. Cables are made for power, signal and instrument installations in hospitals, high rise buildings, railroad cars, subways, on board ship, oil rigs and oil production platforms. The offshore cables are specially constructed to withstand the rugged climatic conditions in the North Sea area.

Noise: My 62 years of it!

NASA Astrophysics Data System (ADS)

Miller, Laymon N.

2004-05-01

Imagine getting paid for having fun! Well, in retrospect, it was fun; but there were several tough challenges. Even those are worth remembering. From 1941 to 1982, there were acoustic torpedoes, HVAC acoustics, noise and vibration in auditoriums, aircraft and airport noise, OSHA and industrial noise control, power plants, community noise problems, vbration, railroad and subway vibration control, legal acoustics, noise manuals, and noise courses-and a few other things that don't fit into those neat categories. Some specific jobs could be named, but that would take away the suspense and the surprise. But 1941 to 1982 is only 41 years. How about the other 20-odd years?

The effect of inclined soil layers on surface vibration from underground railways using a semi-analytical approach

NASA Astrophysics Data System (ADS)

Jones, S.; Hunt, H.

2009-08-01

Ground vibration due to underground railways is a significant source of disturbance for people living or working near the subways. The numerical models used to predict vibration levels have inherent uncertainty which must be understood to give confidence in the predictions. A semi-analytical approach is developed herein to investigate the effect of soil layering on the surface vibration of a halfspace where both soil properties and layer inclination angles are varied. The study suggests that both material properties and inclination angle of the layers have significant effect (± 10dB) on the surface vibration response.

The effects of tunnel horizontal distance on the vertical deformations of an adjacent building

NASA Astrophysics Data System (ADS)

Balkaya, Müge

2015-12-01

Due to the rapid development of urbanization and the need for effective transportation, it became a common application to construct subway tunnels in modern cities. However, these construction activities may lead to undesirable deformations on the adjacent buildings. In this study, the effect of tunnel horizontal distance on the deformations of an adjacent building is investigated using 2D finite element analysis. The results of the finite element analysis showed that, although high settlement values were not observed for the cases investigated in this study, the vertical deformations of the building decreased as the tunnel moved away from the building.

Mass transit and appropriate technology

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

Bell, L.

1978-06-01

Population pressures, dwinding fossil-fuel reserves, and new technological developments will make mass transet more and more competitive with private automobiles in the future. But future transit systems require a combination of high and low technologies--automated subways and conventional sidewalks. Buses and taxicabs may still be the answer in some cities, because more-sophisticated technologies may cause more problems than they solve. Larry Bell reviews information on some of the more advanced transit systems--those in service, proposed, and defunct. He concludes that the most appropriate thechnology for each problem will be found by aiming at balanced, integrated solutions that consider all responablemore » options. (MCW)« less

The Simultaneous Production Model; A Model for the Construction, Testing, Implementation and Revision of Educational Computer Simulation Environments.

ERIC Educational Resources Information Center

Zillesen, Pieter G. van Schaick

This paper introduces a hardware and software independent model for producing educational computer simulation environments. The model, which is based on the results of 32 studies of educational computer simulations program production, implies that educational computer simulation environments are specified, constructed, tested, implemented, and…

Comparative Study of the Effectiveness of Three Learning Environments: Hyper-Realistic Virtual Simulations, Traditional Schematic Simulations and Traditional Laboratory

ERIC Educational Resources Information Center

Martinez, Guadalupe; Naranjo, Francisco L.; Perez, Angel L.; Suero, Maria Isabel; Pardo, Pedro J.

2011-01-01

This study compared the educational effects of computer simulations developed in a hyper-realistic virtual environment with the educational effects of either traditional schematic simulations or a traditional optics laboratory. The virtual environment was constructed on the basis of Java applets complemented with a photorealistic visual output.…

The Development and Evaluation of a Computer-Simulated Science Inquiry Environment Using Gamified Elements

ERIC Educational Resources Information Center

Tsai, Fu-Hsing

2018-01-01

This study developed a computer-simulated science inquiry environment, called the Science Detective Squad, to engage students in investigating an electricity problem that may happen in daily life. The environment combined the simulation of scientific instruments and a virtual environment, including gamified elements, such as points and a story for…

Simulation fails to replicate stress in trainees performing a technical procedure in the clinical environment.

PubMed

Baker, B G; Bhalla, A; Doleman, B; Yarnold, E; Simons, S; Lund, J N; Williams, J P

2017-01-01

Simulation-based training (SBT) has become an increasingly important method by which doctors learn. Stress has an impact upon learning, performance, technical, and non-technical skills. However, there are currently no studies that compare stress in the clinical and simulated environment. We aimed to compare objective (heart rate variability, HRV) and subjective (state trait anxiety inventory, STAI) measures of stress theatre with a simulated environment. HRV recordings were obtained from eight anesthetic trainees performing an uncomplicated rapid sequence induction at pre-determined procedural steps using a wireless Polar RS800CX monitor © in an emergency theatre setting. This was repeated in the simulated environment. Participants completed an STAI before and after the procedure. Eight trainees completed the study. The theatre environment caused an increase in objective stress vs baseline (p = .004). There was no significant difference between average objective stress levels across all time points (p = .20) between environments. However, there was a significant interaction between the variables of objective stress and environment (p = .045). There was no significant difference in subjective stress (p = .27) between environments. Simulation was unable to accurately replicate the stress of the technical procedure. This is the first study that compares the stress during SBT with the theatre environment and has implications for the assessment of simulated environments for use in examinations, rating of technical and non-technical skills, and stress management training.

Development of an Interactive Augmented Environment and Its Application to Autonomous Learning for Quadruped Robots

NASA Astrophysics Data System (ADS)

Kobayashi, Hayato; Osaki, Tsugutoyo; Okuyama, Tetsuro; Gramm, Joshua; Ishino, Akira; Shinohara, Ayumi

This paper describes an interactive experimental environment for autonomous soccer robots, which is a soccer field augmented by utilizing camera input and projector output. This environment, in a sense, plays an intermediate role between simulated environments and real environments. We can simulate some parts of real environments, e.g., real objects such as robots or a ball, and reflect simulated data into the real environments, e.g., to visualize the positions on the field, so as to create a situation that allows easy debugging of robot programs. The significant point compared with analogous work is that virtual objects are touchable in this system owing to projectors. We also show the portable version of our system that does not require ceiling cameras. As an application in the augmented environment, we address the learning of goalie strategies on real quadruped robots in penalty kicks. We make our robots utilize virtual balls in order to perform only quadruped locomotion in real environments, which is quite difficult to simulate accurately. Our robots autonomously learn and acquire more beneficial strategies without human intervention in our augmented environment than those in a fully simulated environment.

A comparison of the accuracy of intraoral scanners using an intraoral environment simulator

PubMed Central

Park, Hye-Nan; Lim, Young-Jun; Yi, Won-Jin

2018-01-01

PURPOSE The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. MATERIALS AND METHODS A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. RESULTS The differences in intraoral environments were not statistically significant (P>.05). Between intraoral scanners, statistically significant differences (P<.05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. CONCLUSION No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future. PMID:29503715

Interactive 4D Visualization of Sediment Transport Models

NASA Astrophysics Data System (ADS)

Butkiewicz, T.; Englert, C. M.

2013-12-01

Coastal sediment transport models simulate the effects that waves, currents, and tides have on near-shore bathymetry and features such as beaches and barrier islands. Understanding these dynamic processes is integral to the study of coastline stability, beach erosion, and environmental contamination. Furthermore, analyzing the results of these simulations is a critical task in the design, placement, and engineering of coastal structures such as seawalls, jetties, support pilings for wind turbines, etc. Despite the importance of these models, there is a lack of available visualization software that allows users to explore and perform analysis on these datasets in an intuitive and effective manner. Existing visualization interfaces for these datasets often present only one variable at a time, using two dimensional plan or cross-sectional views. These visual restrictions limit the ability to observe the contents in the proper overall context, both in spatial and multi-dimensional terms. To improve upon these limitations, we use 3D rendering and particle system based illustration techniques to show water column/flow data across all depths simultaneously. We can also encode multiple variables across different perceptual channels (color, texture, motion, etc.) to enrich surfaces with multi-dimensional information. Interactive tools are provided, which can be used to explore the dataset and find regions-of-interest for further investigation. Our visualization package provides an intuitive 4D (3D, time-varying) visualization of sediment transport model output. In addition, we are also integrating real world observations with the simulated data to support analysis of the impact from major sediment transport events. In particular, we have been focusing on the effects of Superstorm Sandy on the Redbird Artificial Reef Site, offshore of Delaware Bay. Based on our pre- and post-storm high-resolution sonar surveys, there has significant scour and bedform migration around the sunken subway cars and other vessels present at the Redbird site. Due to the extensive surveying and historical data availability in the area, the site is highly attractive for comparing hindcasted sediment transport simulations to our observations of actual changes. This work has the potential to strengthen the accuracy of sediment transport modeling, as well as help predict and prepare for future changes due to similar extreme sediment transport events. Our visualization showing a simple sediment transport model with tidal flows causing significant erosion (red) and deposition (blue).

A methodology towards virtualisation-based high performance simulation platform supporting multidisciplinary design of complex products

NASA Astrophysics Data System (ADS)

Ren, Lei; Zhang, Lin; Tao, Fei; (Luke) Zhang, Xiaolong; Luo, Yongliang; Zhang, Yabin

2012-08-01

Multidisciplinary design of complex products leads to an increasing demand for high performance simulation (HPS) platforms. One great challenge is how to achieve high efficient utilisation of large-scale simulation resources in distributed and heterogeneous environments. This article reports a virtualisation-based methodology to realise a HPS platform. This research is driven by the issues concerning large-scale simulation resources deployment and complex simulation environment construction, efficient and transparent utilisation of fine-grained simulation resources and high reliable simulation with fault tolerance. A framework of virtualisation-based simulation platform (VSIM) is first proposed. Then the article investigates and discusses key approaches in VSIM, including simulation resources modelling, a method to automatically deploying simulation resources for dynamic construction of system environment, and a live migration mechanism in case of faults in run-time simulation. Furthermore, the proposed methodology is applied to a multidisciplinary design system for aircraft virtual prototyping and some experiments are conducted. The experimental results show that the proposed methodology can (1) significantly improve the utilisation of fine-grained simulation resources, (2) result in a great reduction in deployment time and an increased flexibility for simulation environment construction and (3)achieve fault tolerant simulation.

Prioritizing recovery of urban lifelines in the aftermath of hazards: Transportation in post-Harvey Houston

NASA Astrophysics Data System (ADS)

Warner, M. E.; Bhatia, U.; Sela, L.; Wang, R.; Kodra, E.; Ganguly, A. R.

2017-12-01

A well-designed recovery strategy for lifeline infrastructure networks can lead to faster and more reliable restoration of essential services in the aftermath of natural catastrophes such as hurricanes or earthquakes. Urban and regional lifelines impact one another, while the recovery of urban lifelines in turn impacts regional infrastructural resilience, owing to the interdependence of lifelines across scales. Prior work by our team, often in collaboration, has led to the development of new recovery approaches based on network science and engineering, including centrality measures from network science, information theoretic metrics, and network optimization approaches. We have developed proof-of-concept demonstrations at both regional scales, such as for the Indian Railways Network and the US National Airspace System both subjected to multiple hazards, and to urban settings, such as the post-Hurricane recovery of combined power-subway system-of-systems in Boston and the New York City MTA after Hurricane Sandy. Here we make an attempt to understand how such methods may have been, or continue to be, applicable to the transportation network in Houston post-Harvey, and more broadly, how and to what extent lessons learned in urban and regional resilience may generalize across cases. We make an assessment of the state of the literature, process understanding, simulation models, data science methods, and best practices, necessary to address problems of this nature, with a particular focus on post-Harvey recovery of transportation services in Houston.

A Collaborative Extensible User Environment for Simulation and Knowledge Management

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

Freedman, Vicky L.; Lansing, Carina S.; Porter, Ellen A.

2015-06-01

In scientific simulation, scientists use measured data to create numerical models, execute simulations and analyze results from advanced simulators executing on high performance computing platforms. This process usually requires a team of scientists collaborating on data collection, model creation and analysis, and on authorship of publications and data. This paper shows that scientific teams can benefit from a user environment called Akuna that permits subsurface scientists in disparate locations to collaborate on numerical modeling and analysis projects. The Akuna user environment is built on the Velo framework that provides both a rich client environment for conducting and analyzing simulations andmore » a Web environment for data sharing and annotation. Akuna is an extensible toolset that integrates with Velo, and is designed to support any type of simulator. This is achieved through data-driven user interface generation, use of a customizable knowledge management platform, and an extensible framework for simulation execution, monitoring and analysis. This paper describes how the customized Velo content management system and the Akuna toolset are used to integrate and enhance an effective collaborative research and application environment. The extensible architecture of Akuna is also described and demonstrates its usage for creation and execution of a 3D subsurface simulation.« less

Research on Evaluation and Control of Karst Water Resources in a Certain Tunnel of Dalian Subway

NASA Astrophysics Data System (ADS)

Wang, Guang Qiang

2018-05-01

Taking a certain tunnel in Dalian Metro as the research object, to evaluate the situation of karst development through geophysical prospecting and drilling data in study area. Karst water resources can be evaluated by quality and quantity in the study area, the correlation of the ion content can be analyzed according to the analysis results of chemical composition of groundwater and the maximum water inflow in karst water section tunnel can be calculated by using the Oshima Yoshi formula. Put forward measures and methods of groundwater control and tube well dewatering based on these evaluation, it has certain guiding significance for tunnel construction in karst area.

Fuzzy logic in control systems: Fuzzy logic controller. I, II

NASA Technical Reports Server (NTRS)

Lee, Chuen Chien

1990-01-01

Recent advances in the theory and applications of fuzzy-logic controllers (FLCs) are examined in an analytical review. The fundamental principles of fuzzy sets and fuzzy logic are recalled; the basic FLC components (fuzzification and defuzzification interfaces, knowledge base, and decision-making logic) are described; and the advantages of FLCs for incorporating expert knowledge into a control system are indicated. Particular attention is given to fuzzy implication functions, the interpretation of sentence connectives (and, also), compositional operators, and inference mechanisms. Applications discussed include the FLC-guided automobile developed by Sugeno and Nishida (1985), FLC hardware systems, FLCs for subway trains and ship-loading cranes, fuzzy-logic chips, and fuzzy computers.

PELS (Planetary Environmental Liquid Simulator): a new type of simulation facility to study extraterrestrial aqueous environments.

PubMed

Martin, Derek; Cockell, Charles S

2015-02-01

Investigations of other planetary bodies, including Mars and icy moons such as Enceladus and Europa, show that they may have hosted aqueous environments in the past and may do so even today. Therefore, a major challenge in astrobiology is to build facilities that will allow us to study the geochemistry and habitability of these extraterrestrial environments. Here, we describe a simulation facility (PELS: Planetary Environmental Liquid Simulator) with the capability for liquid input and output that allows for the study of such environments. The facility, containing six separate sample vessels, allows for statistical replication of samples. Control of pressure, gas composition, UV irradiation conditions, and temperature allows for the precise replication of aqueous conditions, including subzero brines under martian atmospheric conditions. A sample acquisition system allows for the collection of both liquid and solid samples from within the chamber without breaking the atmospheric conditions, enabling detailed studies of the geochemical evolution and habitability of past and present extraterrestrial environments. The facility we describe represents a new frontier in planetary simulation-continuous flow-through simulation of extraterrestrial aqueous environments.

Methodology for testing infrared focal plane arrays in simulated nuclear radiation environments

NASA Astrophysics Data System (ADS)

Divita, E. L.; Mills, R. E.; Koch, T. L.; Gordon, M. J.; Wilcox, R. A.; Williams, R. E.

1992-07-01

This paper summarizes test methodology for focal plane array (FPA) testing that can be used for benign (clear) and radiation environments, and describes the use of custom dewars and integrated test equipment in an example environment. The test methodology, consistent with American Society for Testing Materials (ASTM) standards, is presented for the total accumulated gamma dose, transient dose rate, gamma flux, and neutron fluence environments. The merits and limitations of using Cobalt 60 for gamma environment simulations and of using various fast-neutron reactors and neutron sources for neutron simulations are presented. Test result examples are presented to demonstrate test data acquisition and FPA parameter performance under different measurement conditions and environmental simulations.

Theory of quantized systems: formal basis for DEVS/HLA distributed simulation environment

NASA Astrophysics Data System (ADS)

Zeigler, Bernard P.; Lee, J. S.

1998-08-01

In the context of a DARPA ASTT project, we are developing an HLA-compliant distributed simulation environment based on the DEVS formalism. This environment will provide a user- friendly, high-level tool-set for developing interoperable discrete and continuous simulation models. One application is the study of contract-based predictive filtering. This paper presents a new approach to predictive filtering based on a process called 'quantization' to reduce state update transmission. Quantization, which generates state updates only at quantum level crossings, abstracts a sender model into a DEVS representation. This affords an alternative, efficient approach to embedding continuous models within distributed discrete event simulations. Applications of quantization to message traffic reduction are discussed. The theory has been validated by DEVSJAVA simulations of test cases. It will be subject to further test in actual distributed simulations using the DEVS/HLA modeling and simulation environment.

Investigation of Propagation in Foliage Using Simulation Techniques

DTIC Science & Technology

2011-12-01

simulation models provide a rough approximation to radiowave propagation in an actual rainforest environment. Based on the simulated results, the...simulation models provide a rough approximation to radiowave propagation in an actual rainforest environment. Based on the simulated results, the path... Rainforest ...............................2 2. Electrical Properties of a Forest .........................................................3 B. OBJECTIVES OF

Three-dimensional simulation and auto-stereoscopic 3D display of the battlefield environment based on the particle system algorithm

NASA Astrophysics Data System (ADS)

Ning, Jiwei; Sang, Xinzhu; Xing, Shujun; Cui, Huilong; Yan, Binbin; Yu, Chongxiu; Dou, Wenhua; Xiao, Liquan

2016-10-01

The army's combat training is very important now, and the simulation of the real battlefield environment is of great significance. Two-dimensional information has been unable to meet the demand at present. With the development of virtual reality technology, three-dimensional (3D) simulation of the battlefield environment is possible. In the simulation of 3D battlefield environment, in addition to the terrain, combat personnel and the combat tool ,the simulation of explosions, fire, smoke and other effects is also very important, since these effects can enhance senses of realism and immersion of the 3D scene. However, these special effects are irregular objects, which make it difficult to simulate with the general geometry. Therefore, the simulation of irregular objects is always a hot and difficult research topic in computer graphics. Here, the particle system algorithm is used for simulating irregular objects. We design the simulation of the explosion, fire, smoke based on the particle system and applied it to the battlefield 3D scene. Besides, the battlefield 3D scene simulation with the glasses-free 3D display is carried out with an algorithm based on GPU 4K super-multiview 3D video real-time transformation method. At the same time, with the human-computer interaction function, we ultimately realized glasses-free 3D display of the simulated more realistic and immersed 3D battlefield environment.

The Lewis Research Center geomagnetic substorm simulation facility

NASA Technical Reports Server (NTRS)

Berkopec, F. D.; Stevens, N. J.; Sturman, J. C.

1977-01-01

A simulation facility was established to determine the response of typical spacecraft materials to the geomagnetic substorm environment and to evaluate instrumentation that will be used to monitor spacecraft system response to this environment. Space environment conditions simulated include the thermal-vacuum conditions of space, solar simulation, geomagnetic substorm electron fluxes and energies, and the low energy plasma environment. Measurements for spacecraft material tests include sample currents, sample surface potentials, and the cumulative number of discharges. Discharge transients are measured by means of current probes and oscilloscopes and are verified by a photomultiplier. Details of this facility and typical operating procedures are presented.

Evaluation of the effects of solar radiation on glass. [space environment simulation

NASA Technical Reports Server (NTRS)

Firestone, R. F.; Harada, Y.

1979-01-01

The degradation of glass used on space structures due to electromagnetic and particulate radiation in a space environment was evaluated. The space environment was defined and a simulated space exposure apparatus was constructed. Four optical materials were exposed to simulated solar and particulate radiation in a space environment. Sapphire and fused silica experienced little change in transmittance, while optical crown glass and ultra low expansion glass darkened appreciably. Specimen selection and preparation, exposure conditions, and the effect of simulated exposure are discussed. A selective bibliography of the effect of radiation on glass is included.

Virtual operating room for team training in surgery.

PubMed

Abelson, Jonathan S; Silverman, Elliott; Banfelder, Jason; Naides, Alexandra; Costa, Ricardo; Dakin, Gregory

2015-09-01

We proposed to develop a novel virtual reality (VR) team training system. The objective of this study was to determine the feasibility of creating a VR operating room to simulate a surgical crisis scenario and evaluate the simulator for construct and face validity. We modified ICE STORM (Integrated Clinical Environment; Systems, Training, Operations, Research, Methods), a VR-based system capable of modeling a variety of health care personnel and environments. ICE STORM was used to simulate a standardized surgical crisis scenario, whereby participants needed to correct 4 elements responsible for loss of laparoscopic visualization. The construct and face validity of the environment were measured. Thirty-three participants completed the VR simulation. Attendings completed the simulation in less time than trainees (271 vs 201 seconds, P = .032). Participants felt the training environment was realistic and had a favorable impression of the simulation. All participants felt the workload of the simulation was low. Creation of a VR-based operating room for team training in surgery is feasible and can afford a realistic team training environment. Copyright © 2015 Elsevier Inc. All rights reserved.

An object oriented Python interface for atomistic simulations

NASA Astrophysics Data System (ADS)

Hynninen, T.; Himanen, L.; Parkkinen, V.; Musso, T.; Corander, J.; Foster, A. S.

2016-01-01

Programmable simulation environments allow one to monitor and control calculations efficiently and automatically before, during, and after runtime. Environments directly accessible in a programming environment can be interfaced with powerful external analysis tools and extensions to enhance the functionality of the core program, and by incorporating a flexible object based structure, the environments make building and analysing computational setups intuitive. In this work, we present a classical atomistic force field with an interface written in Python language. The program is an extension for an existing object based atomistic simulation environment.

Psychological and physiological human responses to simulated and real environments: A comparison between Photographs, 360° Panoramas, and Virtual Reality.

PubMed

Higuera-Trujillo, Juan Luis; López-Tarruella Maldonado, Juan; Llinares Millán, Carmen

2017-11-01

Psychological research into human factors frequently uses simulations to study the relationship between human behaviour and the environment. Their validity depends on their similarity with the physical environments. This paper aims to validate three environmental-simulation display formats: photographs, 360° panoramas, and virtual reality. To do this we compared the psychological and physiological responses evoked by simulated environments set-ups to those from a physical environment setup; we also assessed the users' sense of presence. Analysis show that 360° panoramas offer the closest to reality results according to the participants' psychological responses, and virtual reality according to the physiological responses. Correlations between the feeling of presence and physiological and other psychological responses were also observed. These results may be of interest to researchers using environmental-simulation technologies currently available in order to replicate the experience of physical environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Using IMPRINT to Guide Experimental Design with Simulated Task Environments

DTIC Science & Technology

2015-06-18

USING IMPRINT TO GUIDE EXPERIMENTAL DESIGN OF SIMULATED TASK ENVIRONMENTS THESIS Gregory...ENG-MS-15-J-052 USING IMPRINT TO GUIDE EXPERIMENTAL DESIGN WITH SIMULATED TASK ENVIRONMENTS THESIS Presented to the Faculty Department...Civilian, USAF June 2015 DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENG-MS-15-J-052 USING IMPRINT

Future ultra-speed tube-flight

NASA Astrophysics Data System (ADS)

Salter, Robert M.

1994-05-01

Future long-link, ultra-speed, surface transport systems will require electromagnetically (EM) driven and restrained vehicles operating under reduced-atmosphere in very straight tubes. Such tube-flight trains will be safe, energy conservative, pollution-free, and in a protected environment. Hypersonic (and even hyperballistic) speeds are theoretically achievable. Ultimate system choices will represent tradeoffs between amoritized capital costs (ACC) and operating costs. For example, long coasting links might employ aerodynamic lift coupled with EM restraint and drag make-up. Optimized, combined EM lift, and thrust vectors could reduce energy costs but at increased ACC. (Repulsive levitation can produce lift-over-drag l/d ratios a decade greater than aerodynamic), Alternatively, vehicle-emanated, induced-mirror fields in a conducting (aluminum sheet) road bed could reduce ACC but at substantial energy costs. Ultra-speed tube flight will demand fast-acting, high-precision sensors and computerized magnetic shimming. This same control system can maintain a magnetic 'guide way' invariant in inertial space with inertial detectors imbedded in tube structures to sense and correct for earth tremors. Ultra-speed tube flight can complete with aircraft for transit time and can provide even greater passenger convenience by single-model connections with local subways and feeder lines. Although cargo transport generally will not need to be performed at ultra speeds, such speeds may well be desirable for high throughput to optimize channel costs. Thus, a large and expensive pipeline might be replaced with small EM-driven pallets at high speeds.

Future ultra-speed tube-flight

NASA Technical Reports Server (NTRS)

Salter, Robert M.

1994-01-01

Future long-link, ultra-speed, surface transport systems will require electromagnetically (EM) driven and restrained vehicles operating under reduced-atmosphere in very straight tubes. Such tube-flight trains will be safe, energy conservative, pollution-free, and in a protected environment. Hypersonic (and even hyperballistic) speeds are theoretically achievable. Ultimate system choices will represent tradeoffs between amoritized capital costs (ACC) and operating costs. For example, long coasting links might employ aerodynamic lift coupled with EM restraint and drag make-up. Optimized, combined EM lift, and thrust vectors could reduce energy costs but at increased ACC. (Repulsive levitation can produce lift-over-drag l/d ratios a decade greater than aerodynamic), Alternatively, vehicle-emanated, induced-mirror fields in a conducting (aluminum sheet) road bed could reduce ACC but at substantial energy costs. Ultra-speed tube flight will demand fast-acting, high-precision sensors and computerized magnetic shimming. This same control system can maintain a magnetic 'guide way' invariant in inertial space with inertial detectors imbedded in tube structures to sense and correct for earth tremors. Ultra-speed tube flight can complete with aircraft for transit time and can provide even greater passenger convenience by single-model connections with local subways and feeder lines. Although cargo transport generally will not need to be performed at ultra speeds, such speeds may well be desirable for high throughput to optimize channel costs. Thus, a large and expensive pipeline might be replaced with small EM-driven pallets at high speeds.

A Simulated Learning Environment for Teaching Medicine Dispensing Skills

PubMed Central

Styles, Kim; Sewell, Keith; Trinder, Peta; Marriott, Jennifer; Maher, Sheryl; Naidu, Som

2016-01-01

Objective. To develop an authentic simulation of the professional practice dispensary context for students to develop their dispensing skills in a risk-free environment. Design. A development team used an Agile software development method to create MyDispense, a web-based simulation. Modeled on virtual learning environments elements, the software employed widely available standards-based technologies to create a virtual community pharmacy environment. Assessment. First-year pharmacy students who used the software in their tutorials, were, at the end of the second semester, surveyed on their prior dispensing experience and their perceptions of MyDispense as a tool to learn dispensing skills. Conclusion. The dispensary simulation is an effective tool for helping students develop dispensing competency and knowledge in a safe environment. PMID:26941437

Concentrations and elemental composition of particulate matter in the Buenos Aires underground system

NASA Astrophysics Data System (ADS)

Murruni, L. G.; Solanes, V.; Debray, M.; Kreiner, A. J.; Davidson, J.; Davidson, M.; Vázquez, M.; Ozafrán, M.

Total suspended particulate (TSP) samples have been collected at six stations in the C and B lines of the Buenos Aires underground system and, almost simultaneously, at six ground level sites outside and nearby the corresponding underground stations, in the Oct 2005/Oct 2006 period. All these samples were analyzed for mass and elemental Fe, Cu, and Zn concentrations by using the Particle Induced X-ray Emission (PIXE) technique. Mostly, TSP concentrations were found to be between 152 μg m -3 (25% percentile) and 270 μg m -3 (75% percentile) in the platform of the stations, while those in outside ambient air oscillated from 55 μg m -3 (25% percentile) to 137 μg m -3 (75% percentile). Moreover, experimental results indicate that TSP levels are comparable to those measured for other underground systems worldwide. Statistical results demonstrate that subway TSP levels are about 3 times larger on average than those for urban ambient air. The TSP levels inside stations and outdoors are poorly correlated, indicating that TSP levels in the metro system are mainly influenced by internal sources. Regarding metal concentrations, the most enriched element in TSP samples was Fe, the levels of which ranged from 36 (25% percentile) to 86 μg m -3 (75% percentile) in Line C stations, while in Line B ones they varied between 8 μg m -3 (25% percentile) and 46 μg m -3 (75% percentile). As a comparison, Fe concentrations in ambient air oscillated between 0.7 μg m -3 (25% percentile) and 1.2 μg m -3 (75% percentile). Other enriched elements include Cu and Zn. With regard to their sources, Fe and Cu have been related to processes taking place inside the subway system, while Zn has been associated with outdoor vehicular traffic. Additionally, concerns about possible health implications based on comparisons to various indoor air quality limits and available toxicological information are discussed.

Measurement of ground and nearby building vibration and noise induced by trains in a metro depot.

PubMed

Zou, Chao; Wang, Yimin; Wang, Peng; Guo, Jixing

2015-12-01

Metro depots are where subway trains are parked and where maintenance is carried out. They usually occupy the largest ground areas in metro projects. Due to land utilization problems, Chinese cities have begun to develop over-track buildings above metro depots for people's life and work. The frequently moving trains, when going into and out of metro depots, can cause excessive vibration and noise to over-track buildings and adversely affect the living quality of the building occupants. Considering the current need of reliable experimental data for the construction of metro depots, field measurements of vibration and noise on the ground and inside a nearby 3-story building subjected to moving subway trains were conducted in a metro depot at Guangzhou, China. The amplitudes and frequency contents of velocity levels were quantified and compared. The composite A-weighted equivalent sound levels and maximum sound levels were captured. The predicted models for vibration and noise of metro depot were proposed based on existing models and verified. It was found that the vertical vibrations were significantly greater than the horizontal vibrations on the ground and inside the building near the testing line. While at the throat area, the horizontal vibrations near the curved track were remarkably greater than the vertical vibrations. The attenuation of the vibrations with frequencies above 50 Hz was larger than the ones below 50 Hz, and the frequencies of vibration transmitting to adjacent buildings were mainly within 10-50 Hz. The largest equivalent sound level generated in the throat area was smaller than the testing line one, but the instantaneous maximum sound level induced by wheels squeal, contact between wheels and rail joints as well as turnout was close to or even greater than the testing line one. The predicted models gave a first estimation for design and assessment of newly built metro depots. Copyright © 2015 Elsevier B.V. All rights reserved.

Unraveling bacterial fingerprints of city subways from microbiome 16S gene profiles.

PubMed

Walker, Alejandro R; Grimes, Tyler L; Datta, Somnath; Datta, Susmita

2018-05-22

Microbial communities can be location specific, and the abundance of species within locations can influence our ability to determine whether a sample belongs to one city or another. As part of the 2017 CAMDA MetaSUB Inter-City Challenge, next generation sequencing (NGS) data was generated from swipe samples collected from subway stations in Boston, New York City hereafter New York, and Sacramento. DNA was extracted and Illumina sequenced. Sequencing data was provided for all cities as part of 2017 CAMDA contest challenge dataset. Principal component analysis (PCA) showed clear clustering of the samples for the three cities, with a substantial proportion of the variance explained by the first three components. We ran two different classifiers and results were robust for error rate (< 6%) and accuracy (> 95%). The analysis of variance (ANOVA) demonstrated that overall, bacterial composition across the three cities is significantly different. A similar conclusion was reached using a novel bootstrap based test using diversity indices. Last but not least, a co-abundance association network analyses for the taxonomic levels "order", "family", and "genus" found different patterns of bacterial networks for the three cities. Bacterial fingerprint can be useful to predict sample provenance. In this work prediction of provenance reported with over 95% accuracy. Association based network analysis, emphasized similarities between the closest cities sharing common bacterial composition. ANOVA showed different patterns of bacterial amongst cities, and these findings strongly suggest that bacterial signature across multiple cities are different. This work advocates a data analysis pipeline which could be followed in order to get biological insight from this data. However, the biological conclusions from this analysis is just an early indication out of a pilot microbiome data provided to us through CAMDA 2017 challenge and will be subject to change as we get more complete data sets in the near future. This microbiome data can have potential applications in forensics, ecology, and other sciences. This article was reviewed by Klas Udekwu, Alexandra Graf, and Rafal Mostowy.

The neurobiological role of the dorsolateral prefrontal cortex in recovery from trauma. Longitudinal brain imaging study among survivors of the South Korean subway disaster.

PubMed

Lyoo, In Kyoon; Kim, Jieun E; Yoon, Sujung J; Hwang, Jaeuk; Bae, Sujin; Kim, Dajung J

2011-07-01

A multiwave longitudinal neuroimaging study in a cohort of direct survivors of a South Korean subway disaster, most of whom recovered from posttraumatic stress disorder 5 years after trauma, provided a unique opportunity to investigate the brain correlates of recovery from a severe psychological trauma. To investigate region-specific brain mobilization during successful recovery from posttraumatic stress disorder by assessing cortical thickness multiple times from early after trauma to recovery, and to examine whether a brain-derived neurotrophic factor gene polymorphism was associated with this brain mobilization. Five-year follow-up case-control study conducted from 2003-2007. Seoul National University and Hospital. Thirty psychologically traumatized disaster survivors and 36 age- and sex-matched control group members recruited from the disaster registry and local community, respectively, who contributed 156 high-resolution brain magnetic resonance images during 3 waves of assessments. Cerebral cortical thickness measured in high-resolution anatomic magnetic resonance images using a validated cortical thickness analysis tool and its prospective changes from early after trauma to recovery in trauma-exposed individuals and controls. Trauma-exposed individuals had greater dorsolateral prefrontal cortical (DLPFC) thickness 1.42 years after trauma (right DLPFC, 5.4%; left superior frontal cortex, 5.8%; and left inferior frontal cortex, 5.3% [all clusters, P ≤ .01]) relative to controls. Thicknesses gradually normalized over time during recovery. We found a positive linear trend, with trauma-exposed individuals with a valine/valine genotype having the greatest DLPFC cortical thickness, followed by those with a methionine genotype and controls (P < .001 for trend). Greater DLPFC thickness was associated with greater posttraumatic stress disorder symptom reductions and better recovery. The DLPFC region might play an important role in psychological recovery from a severely traumatic event in humans.

An examination of speech reception thresholds measured in a simulated reverberant cafeteria environment.

PubMed

Best, Virginia; Keidser, Gitte; Buchholz, Jörg M; Freeston, Katrina

2015-01-01

There is increasing demand in the hearing research community for the creation of laboratory environments that better simulate challenging real-world listening environments. The hope is that the use of such environments for testing will lead to more meaningful assessments of listening ability, and better predictions about the performance of hearing devices. Here we present one approach for simulating a complex acoustic environment in the laboratory, and investigate the effect of transplanting a speech test into such an environment. Speech reception thresholds were measured in a simulated reverberant cafeteria, and in a more typical anechoic laboratory environment containing background speech babble. The participants were 46 listeners varying in age and hearing levels, including 25 hearing-aid wearers who were tested with and without their hearing aids. Reliable SRTs were obtained in the complex environment, but led to different estimates of performance and hearing-aid benefit from those measured in the standard environment. The findings provide a starting point for future efforts to increase the real-world relevance of laboratory-based speech tests.

An examination of speech reception thresholds measured in a simulated reverberant cafeteria environment

PubMed Central

Best, Virginia; Keidser, Gitte; Buchholz, J(x004E7)rg M.; Freeston, Katrina

2016-01-01

Objective There is increasing demand in the hearing research community for the creation of laboratory environments that better simulate challenging real-world listening environments. The hope is that the use of such environments for testing will lead to more meaningful assessments of listening ability, and better predictions about the performance of hearing devices. Here we present one approach for simulating a complex acoustic environment in the laboratory, and investigate the effect of transplanting a speech test into such an environment. Design Speech reception thresholds were measured in a simulated reverberant cafeteria, and in a more typical anechoic laboratory environment containing background speech babble. Study Sample The participants were 46 listeners varying in age and hearing levels, including 25 hearing-aid wearers who were tested with and without their hearing aids. Results Reliable SRTs were obtained in the complex environment, but led to different estimates of performance and hearing aid benefit from those measured in the standard environment. Conclusions The findings provide a starting point for future efforts to increase the real-world relevance of laboratory-based speech tests. PMID:25853616

Using Social Simulations to Assess and Train Potential Leaders to Make Effective Decisions in Turbulent Environments

ERIC Educational Resources Information Center

Hunsaker, L. Phillip

2007-01-01

Purpose: The purpose of this paper is to describe two social simulations created to assess leadership potential and train leaders to make effective decisions in turbulent environments. One is set in the novel environment of a lunar moon colony and the other is a military combat command. The research generated from these simulations for assessing…

Multidisciplinary research leading to utilization of extraterrestrial resources

NASA Technical Reports Server (NTRS)

1972-01-01

Progress of the research accomplished during fiscal year 1972 is reported. The summaries presented include: (1) background analysis and coordination, (2) surface properties of rock in simulated lunar environment, (3) rock failure processes, strength and elastic properties in simulated lunar environment, (4) thermal fragmentation, and thermophysical and optical properties in simulated lunar environment, and (5) use of explosives on the moon.

Design Patterns for Learning and Assessment: Facilitating the Introduction of a Complex Simulation-Based Learning Environment into a Community of Instructors

ERIC Educational Resources Information Center

Frezzo, Dennis C.; Behrens, John T.; Mislevy, Robert J.

2010-01-01

Simulation environments make it possible for science and engineering students to learn to interact with complex systems. Putting these capabilities to effective use for learning, and assessing learning, requires more than a simulation environment alone. It requires a conceptual framework for the knowledge, skills, and ways of thinking that are…

Real-Time and High-Fidelity Simulation Environment for Autonomous Ground Vehicle Dynamics

NASA Technical Reports Server (NTRS)

Cameron, Jonathan; Myint, Steven; Kuo, Calvin; Jain, Abhi; Grip, Havard; Jayakumar, Paramsothy; Overholt, Jim

2013-01-01

This paper reports on a collaborative project between U.S. Army TARDEC and Jet Propulsion Laboratory (JPL) to develop a unmanned ground vehicle (UGV) simulation model using the ROAMS vehicle modeling framework. Besides modeling the physical suspension of the vehicle, the sensing and navigation of the HMMWV vehicle are simulated. Using models of urban and off-road environments, the HMMWV simulation was tested in several ways, including navigation in an urban environment with obstacle avoidance and the performance of a lane change maneuver.

Virtual environments simulation in research reactor

NASA Astrophysics Data System (ADS)

Muhamad, Shalina Bt. Sheik; Bahrin, Muhammad Hannan Bin

2017-01-01

Virtual reality based simulations are interactive and engaging. It has the useful potential in improving safety training. Virtual reality technology can be used to train workers who are unfamiliar with the physical layout of an area. In this study, a simulation program based on the virtual environment at research reactor was developed. The platform used for virtual simulation is 3DVia software for which it's rendering capabilities, physics for movement and collision and interactive navigation features have been taken advantage of. A real research reactor was virtually modelled and simulated with the model of avatars adopted to simulate walking. Collision detection algorithms were developed for various parts of the 3D building and avatars to restrain the avatars to certain regions of the virtual environment. A user can control the avatar to move around inside the virtual environment. Thus, this work can assist in the training of personnel, as in evaluating the radiological safety of the research reactor facility.

A new airborne laser rangefinder dynamic target simulator for non-stationary environment

NASA Astrophysics Data System (ADS)

Ma, Pengge; Pang, Dongdong; Yi, Yang

2017-11-01

For the non-stationary environment simulation in laser range finder product testing, a new dynamic target simulation system is studied. First of all, the three-pulsed laser ranging principle, laser target signal composition and mathematical representation are introduced. Then, the actual nonstationary working environment of laser range finder is analyzed, and points out that the real sunshine background light clutter and target shielding effect in laser echo become the main influencing factors. After that, the dynamic laser target signal simulation method is given. Eventlly, the implementation of automatic test system based on arbitrary waveform generator is described. Practical application shows that the new echo signal automatic test system can simulate the real laser ranging environment of laser range finder, and is suitable for performance test of products.

LEGEND, a LEO-to-GEO Environment Debris Model

NASA Technical Reports Server (NTRS)

Liou, Jer Chyi; Hall, Doyle T.

2013-01-01

LEGEND (LEO-to-GEO Environment Debris model) is a three-dimensional orbital debris evolutionary model that is capable of simulating the historical and future debris populations in the near-Earth environment. The historical component in LEGEND adopts a deterministic approach to mimic the known historical populations. Launched rocket bodies, spacecraft, and mission-related debris (rings, bolts, etc.) are added to the simulated environment. Known historical breakup events are reproduced, and fragments down to 1 mm in size are created. The LEGEND future projection component adopts a Monte Carlo approach and uses an innovative pair-wise collision probability evaluation algorithm to simulate the future breakups and the growth of the debris populations. This algorithm is based on a new "random sampling in time" approach that preserves characteristics of the traditional approach and captures the rapidly changing nature of the orbital debris environment. LEGEND is a Fortran 90-based numerical simulation program. It operates in a UNIX/Linux environment.

Analysis of the effects of simulated synergistic LEO environment on solar panels

NASA Astrophysics Data System (ADS)

Allegri, G.; Corradi, S.; Marchetti, M.; Scaglione, S.

2007-02-01

The effects due to the LEO environment exposure of a solar array primary structure are here presented and discussed in detail. The synergistic damaging components featuring LEO environment are high vacuum, thermal cycling, neutral gas, ultraviolet (UV) radiation and cold plasma. The synergistic effects due to these environmental elements are simulated by "on ground" tests, performed in the Space Environment Simulator (SAS) at the University of Rome "La Sapienza"; numerical simulations are performed by the Space Environment Information System (SPENVIS), developed by the European Space Agency (ESA). A "safe life" design for a solar array primary structure is developed, taking into consideration the combined damaging action of the LEO environment components; therefore results from both numerical and experimental simulations are coupled within the framework of a standard finite element method (FEM) based design. The expected durability of the solar array primary structure, made of laminated sandwich composite, is evaluated assuming that the loads exerted on the structure itself are essentially dependent on thermo-elastic stresses. The optical degradation of surface materials and the stiffness and strength degradation of structural elements are taken into account to assess the global structural durability of the solar array under characteristic operative conditions in LEO environment.

[Cordyceps sinensis enhances lymphocyte proliferation and CD markers expression in simulated microgravity environment].

PubMed

Hao, Tong; Li, Jun-Jie; Du, Zhi-Yan; Duan, Cui-Mi; Wang, Yan-Meng; Wang, Chang-Yong; Song, Jing-Ping; Wang, Lin-Jie; Li, Ying-Hui; Wang, Yan

2012-10-01

This study was aimed to explore the effect of cordyceps sinensis enhancing lymphocyte proliferation and surface CD marker expression in simulated microgravity environment. The splenic lymphocytes were separated from mice and cultured in the rotary cell culture system simulated microgravity environment. The cells were treated with different concentration of cordyceps sinensis solution (0, 6.25, 12.5, 25 and 50 µg/ml) for 24, 48 and 72 h respectively, then the cells were harvested, and analyzed for cell proliferation and the expression of cell surface markers (CD4 and CD8). The results showed that under simulated microgravity environment, the lymphocyte proliferation was inhibited. When the concentration of cordyceps sinensis was 25 or 50 µg/ml, the lymphocyte proliferation, CD4 and CD8 expressions all increased, but 50 µg/ml cordyceps sinensis could inhibit the proliferation ability with the time prolonging. It is concluded that the suitable concentration of cordyceps sinensis displayed the ability to enhance the lymphocyte proliferation and CD marker expression in simulated microgravity environment. These results may be valuable for screening drugs which can be potentially against immunosuppression under simulated microgravity.